Naked Science Forum

General Science => General Science => Topic started by: neilep on 23/02/2006 18:05:29

Title: Recent Science News Stories and Science Articles
Post by: neilep on 23/02/2006 18:05:29
Hi Everybody.

I've noticed that some of you have been posting some science news articles and I thought it might be a good idea to collate them all in one thread......so, if you see anything that you feel is of interest to the site then please feel free to add them here.

When you do, please credit the source.

Thanks

Neil

Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 23/02/2006 18:06:16
Hot alien world is the closest directly detected
NASA NEWS RELEASE
Posted: February 22, 2006

A NASA-led team of astronomers have used NASA's Spitzer Space Telescope to detect a strong flow of heat radiation from a toasty planet orbiting a nearby star. The findings allowed the team to "take the temperature" of the planet.

"This is the closest extrasolar planet to Earth that has ever been detected directly, and it presents the strongest heat emission ever seen from an exoplanet," said Drake Deming of NASA's Goddard Space Flight Center, Greenbelt, Md. Deming is the lead author of a paper on this observation to be published in the Astrophysical Journal on June 10. An advance copy of the paper will be posted on the astro-ph website on Feb. 22.

The planet "HD 189733b" orbits a star that is a near cosmic neighbor to our sun, at a distance of 63 light years in the direction of the Dumbbell Nebula. It orbits the star very closely, just slightly more than three percent of the distance between Earth and the sun. Such close proximity keeps the planet roasting at about 844 Celsius (about 1,551 Fahrenheit), according to the team's measurement.

The planet was discovered last year by François Bouchy of the Marseille Astrophysics Laboratory, France, and his team. The discovery observations allowed Bouchy's team to determine the planet's size (about 1.26 times Jupiter's diameter), mass (1.15 times Jupiter), and density (about 0.75 grams per cubic centimeter). The low density indicates the planet is a gas giant like Jupiter.

The observations also revealed the orbital period (2.219 days) and the distance from the parent star. From this distance and the temperature of the parent star, Bouchy's team estimated the planet's temperature was at least several hundred degrees Celsius, but they were not able to measure heat or light emitted directly from the planet.

"Our direct measurement confirms this estimate," said Deming. This temperature is too high for liquid water to exist on the planet or any moons it might have. Since known forms of life require liquid water, it is unlikely to have emerged there.

Last year, Deming's team and another group based at the Harvard-Smithsonian Center for Astrophysics used Spitzer to make the first direct detection of light from alien worlds, by observing the warm infrared glows of two other previously detected "Hot Jupiter" planets, designated HD 209458b and TrES-1.

Infrared light is invisible to the human eye, but detectable by special instruments. Some infrared light is perceived as heat. Hot Jupiter planets are alien gas giants that zip closely around their parent stars, like HD 189733b. From their close orbits, they soak up ample starlight and shine brightly in infrared wavelengths.

Deming's team used the same method to observe HD 189733b. To distinguish the planet's glow from its hot parent star, the astronomers used an elegant method. First, they used Spitzer to collect the total infrared light from both the star and its planet. Then, when the planet dipped behind the star as part of its regular orbit, the astronomers measured the infrared light coming from just the star. This pinpointed exactly how much infrared light belonged to the planet. Under optimal circumstances this same method can be used to make a crude temperature map of the planet itself.

"The heat signal from this planet is so strong that Spitzer was able to resolve its disk, in the sense that our team could tell we were seeing a round object in the data, not a mere point of light," said Deming. "The current Spitzer observations cannot yet make a temperature map of this world, but more observations by Spitzer or future infrared telescopes in space may be able to do that."

Deming's team includes Joseph Harrington, Cornell University, Ithaca, N.Y.; Sara Seager, Carnegie Institution of Washington; and Jeremy Richardson, NASA Postdoctoral Fellow at Goddard, in the Exoplanets and Stellar Astrophysics Laboratory.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for the agency's Science Mission Directorate. Science operations are conducted at the Spitzer Science Center at Caltech. JPL is a division of Caltech

Source: SPACEFLIGHTNOW.COM


Men are the same as women.... just inside out !!
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Ray hinton on 24/02/2006 12:11:16
going through these pages im constantly reminded of just how small and insignificant we really are,like a speck of dust in the vastness of space.
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 24/02/2006 14:35:14
Birds that make teeth

Gone does not necessarily mean forgotten, especially in biology. A recent finding by researchers at the University of Wisconsin, Madison, and colleagues from the University of Manchester have found new evidence that the ability to form previously lost organs--in this case, teeth--can be maintained millions of years after the last known ancestor possessed them.
Birds do not have teeth. However, their ancestors did--about 70–80 million years ago. The evolutionary loss of teeth corresponded to the formation of the beak that is present in all living birds. Nonetheless, it has been known that if mouse tooth-forming tissue is in contact with bird jaw tissue, the bird tissue is able to follow the instructions given by the mouse tissue and participate in making teeth, and that these teeth look very much like those of mammals. However, Drs. Matthew Harris and John F. Fallon and colleagues have found that modern birds retain the ability to make teeth even without instruction from their tooth-bearing cousins.

In the new work, the researchers show that the talpid2 strain of chicken harbors a genetic change that permits tooth formation in both the upper and lower jaw of embryonic birds. These teeth show similar developmental position as mammalian teeth and are associated with similar molecular instructions. Furthermore, when comparing the initial development of the structures, the researchers realized that the teeth forming in the chicken did not look like mammalian teeth, but resembled those of the alligator, the closest living relative of modern birds.

The findings strongly suggest that the birds were initiating developmental programs similar to those of their reptilian ancestors. In addition, the authors found that the capacity to form teeth still resides in normal chickens and can be triggered experimentally by molecular signals. Taken together, the new findings indicate that even though modern birds lost teeth millions of years ago, the potential to form them persists.


SOURCE: EUREKAALERT.ORG


Men are the same as women.... just inside out !!
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Ray hinton on 24/02/2006 14:39:47
i got a couple of birds next door that make teeth,they work for the dentist i said about,ones quite nice,called wendy.
i might feint a tooth ache one day just to get her to spend time with me !!!!!!!!!![xx(]

RE-HAB IS FOR QUITTERS.
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ariel on 25/02/2006 04:33:06
ray
you and your animals...[:p]
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ariel on 25/02/2006 05:19:18
Beaver or Otter, It Lived in Dinosaurs' Time

(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fgraphics8.nytimes.com%2Fimages%2F2006%2F02%2F23%2Fscience%2F24beav184.jpg&hash=42569e7206fb2ba7087d2be3f2379b39)By JOHN NOBLE WILFORD
Published: February 24, 2006
In the conventional view, the earliest mammals were small, primitive, shrewlike creatures that did not begin to explore the world's varied environments until the dinosaurs died out 65 million years ago.
 
Mark A. Klingler/Carnegie Museum of Natural History
Scientists have found a fossil of a mammal — part beaver, part otter, part platypus — that lived in China 164 million years ago.
But scientists are reporting today that they have uncovered fossils of a swimming, fish-eating mammal that lived in China fully 164 million years ago, well before it was thought that some mammals could have spent much of their lives in water.

The extinct species appears to have been an amalgam of animals. It had a broad, scaly tail, flat like a beaver's. Its sharp teeth seemed ideal for eating fish, like an otter's. Its likely lifestyle — burrowing in tunnels on shore and dog-paddling in water — reminds scientists of the modern platypus.

Its skeleton suggests that it was about 20 inches long, from snout to the tip of its tail, about the length of a small house cat.

The surprising discovery, made in 2004 in the abundant fossil beds of Liaoning Province, China, is being reported in the journal Science by an international team led by Ji Qiang of Nanjing University.

In the article, Dr. Ji and other researchers from the Chinese Academy of Geological Sciences in Beijing and the Carnegie Museum of Natural History in Pittsburgh said the fossil skeleton showed that some mammals occupied more diverse ecological niches than had been suspected in the Jurassic Period, an age dominated by dinosaurs.

Thomas Martin, an authority on early mammals at Senckenberg Research Institute in Frankfurt, said the find pushed back "the mammalian conquest of the waters by more than 100 million years" and "impressively contradicts" the conventional view.

"This exciting fossil," he wrote in a commentary accompanying the report, "is a further jigsaw puzzle piece in a series of recent discoveries, demonstrating that the diversity and early evolutionary history of mammals were much more complex than perceived less than a decade ago."

Despite similarities with some modern animals, the Jurassic mammal has no modern descendants and is not related to any existing species. The discoverers have given it the name Castorocauda lutrasimilis, Latin for beaver tail and similarity to the otter.

Zhe-Xi Luo, one of the discoverers and the curator of vertebrate paleontology at the Carnegie museum, said the specimen was well preserved, unlike the surviving fragments of bone and tooth of most mammals from the dinosaur age.

The skeleton is accompanied by fur and scale imprints and the suggestion of soft-tissue webbing in the hind limbs. Dr. Luo said the fur was to keep water from the animal's skin. It is the most primitive known mammal to be preserved with hair, evidence for its evolution before the appearance of more complex mammals.

The scientists said the tail and limbs of the newfound specimen were well developed for aquatic life. They surmised that like the platypus, Castorocauda swam in rivers and lakes, ate aquatic animals and insects and built nests in burrows along the shore. The animal had molars specialized for feeding on small fish and small aquatic invertebrates.

"So far, it is the only semiaquatic mammal from the Jurassic," Dr. Luo said.

The skeleton was found by peasants in Liaoning, the province in northeast China that in recent years has produced several notable discoveries of mammal diversity. The semiaquatic mammal was uncovered in the same hilly country where paleontologists have collected fossils of feathered dinosaurs and two 130-million-year-old animals that did not fit the lowly image of mammals of that period. One of them, the size of an opossum, had feasted on a small dinosaur just before dying.

Jin Meng of the American Museum of Natural History in Manhattan, one of the discoverers of previous Liaoning mammals but who was not involved in the most recent one, said in a telephone interview that more than a dozen new mammals from that area had recently produced "real evidence to show the diversity of lifestyles and behaviors of mammals" in the age of dinosaurs.

"We have been seeing mammals at that time that were larger than a mouse or rat, some that climbed trees, and now we see some that could swim in water," Dr. Meng said.

That was from AOL News
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 25/02/2006 17:28:37
Thank you for your contribution Ariel. please continue, your posts are welcome.

Men are the same as women.... just inside out !!
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 25/02/2006 17:33:12
Parthenon sculptures were coloured blue, red and green
AFP Friday February 24, 05:53 PM

   

Parthenon sculptures were coloured blue, red and green
ATHENS (AFP) - Its austere white is on every postcard, but the Athens Parthenon was originally daubed with red, blue and green, the Greek archaeologist supervising conservation work on the 2,400-year-old temple said.

"A recent cleaning operation by laser revealed traces of haematite (red), Egyptian blue and malachite-azurite (green-blue) on the sculptures of the western frieze," senior archaeologist Evi Papakonstantinou-Zioti told AFP.

While archaeologists had found traces of the first two colours elsewhere on the temple years ago, the malachite-azurite colouring was only revealed in the latest restoration process, Papakonstantinou-Zioti said.

Given the testimony of ancient writers, it is not unlikely that the Parthenon's trademark columns were also coloured, she added.

Archaeologists have been trying since 1987 to remedy damage wrought on the Parthenon's marble structure by centuries of weather exposure and decades of smog pollution.

Principal restoration work on the entire Acropolis citadel, which stands in the centre of the modern Greek capital, is scheduled to be completed by 2009.

Dedicated to the ancient Greek goddess Athena, patron of the ancient city of Athens, the Parthenon was badly damaged during a Venetian siege of occupying Ottoman Turkish forces in 1687.

Much of the temple's eastern frieze was removed in the early 19th century by agents of Lord Elgin, then British ambassador to the Ottoman Empire.

Elgin subsequently sold the sculptures to the British Museum in London, where they are still on display, despite persistent efforts by the Greek government to secure their return for the past 20 years.

SOURCE: AFP via YAHOO NEWS

Men are the same as women.... just inside out !!
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: another_someone on 25/02/2006 23:49:47
quote:
Originally posted by neilep

Parthenon sculptures were coloured blue, red and green
AFP Friday February 24, 05:53 PM

   

Parthenon sculptures were coloured blue, red and green
ATHENS (AFP) - Its austere white is on every postcard, but the Athens Parthenon was originally daubed with red, blue and green, the Greek archaeologist supervising conservation work on the 2,400-year-old temple said.

"A recent cleaning operation by laser revealed traces of haematite (red), Egyptian blue and malachite-azurite (green-blue) on the sculptures of the western frieze," senior archaeologist Evi Papakonstantinou-Zioti told AFP.

While archaeologists had found traces of the first two colours elsewhere on the temple years ago, the malachite-azurite colouring was only revealed in the latest restoration process, Papakonstantinou-Zioti said.

Given the testimony of ancient writers, it is not unlikely that the Parthenon's trademark columns were also coloured, she added.

Archaeologists have been trying since 1987 to remedy damage wrought on the Parthenon's marble structure by centuries of weather exposure and decades of smog pollution.

Principal restoration work on the entire Acropolis citadel, which stands in the centre of the modern Greek capital, is scheduled to be completed by 2009.

Dedicated to the ancient Greek goddess Athena, patron of the ancient city of Athens, the Parthenon was badly damaged during a Venetian siege of occupying Ottoman Turkish forces in 1687.

Much of the temple's eastern frieze was removed in the early 19th century by agents of Lord Elgin, then British ambassador to the Ottoman Empire.

Elgin subsequently sold the sculptures to the British Museum in London, where they are still on display, despite persistent efforts by the Greek government to secure their return for the past 20 years.

SOURCE: AFP via YAHOO NEWS

Men are the same as women.... just inside out !!



Lord Elgin bought the Elgin marbles from the Turkish government, who had legal jurisdiction over Greece at the time (by right of conquest).  The fact that after the Greeks successfully rebelled against their Turkish overlords (facilitated by the general state of collapse of the Ottoman empire, and European support for Greek 'terrorist' activity) they then declared the sale illegal after the fact is something else.

(and, yes, I am being deliberately provocative – simple saying there are two sides to every story).

http://en.wikipedia.org/wiki/Thomas_Bruce%2C_7th_Earl_of_Elgin
quote:

Elgin was ambassador to the Ottoman Empire between 1799 and 1803. He had a great enthusiasm for antiquities, and was shocked by the indifference of the ruling Turks to the worsening condition of the sculptures. His motive in removing them was to preserve them, but his workers did considerable damage in the process. Even at the time, his actions were controversial. Elgin spent vast amounts of money in having them shipped home to Britain, which he never recouped.



As for the perils of preservation:

http://en.wikipedia.org/wiki/Elgin_Marbles
quote:

The housing of the marbles in the British Museum has been a mixed blessing. While the artifacts held in London, unlike those on the Parthenon, have been saved from the hazards of the elements, they have also been irrevocably damaged by the "cleaning" methods employed by the British Museum in the 1930s. Acting under the erroneous belief that the marbles were originally bright white, the marbles were cleaned with metal tools and caustics, causing serious damage and altering the marbles' coloring. (The Pentelicon marble on which the carvings were made naturally acquire a tan color similar to honey when exposed to air.) In addition, the process scraped away all traces of surface coloring that the marbles originally held. As such, the marbles in both locations have suffered: while the marbles of the Parthenon have been damaged by weather, the ones held in Britain have been damaged by faulty methods.





George
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 02/03/2006 14:15:40
Amber reveals ecology of 30 million year old spiders

Scientists at The University of Manchester and the Manchester Metropolitan University have carried out the first comparative scientific study of ancient spiders trapped in amber more than 30 millions years ago.

The study of fossilised spiders from the Baltic (Poland) and the Dominican (Caribbean) regions has revealed new insights into the ecologies of spiders dating back to the Cenozoic period.

It is the first time ancient spiders from different parts of the world have been compared on such a large scale. 671 species of spiders were compared in the study which is published in the March issue of the Royal Society's Journal Biology Letters.

Palaeoarachnologist Dr David Penney, of The University of Manchester's School of Earth, Atmospheric and Environmental Sciences who led the research, said: "Amber provides a unique window into past forest ecosystems. It retains an incredible amount of information, not just about the spiders themselves, but also about the environment in which they lived.

"We have not only been able to compare the size distributions of over 600 spiders but we have also been able to gain unique insights into the forest in which they lived."

By analysing the size distributions of the spiders and comparing the distinct hunting traits of each species, Dr Penney found that web-spinning spiders were bigger in Baltic amber than in Dominican amber, but that there was no difference between hunting spiders in either region. It was also found the fauna of the amber producing trees in each region accounted for this difference in size.

"Several lines of evidence show that greater structural complexity of Baltic compared to Dominican amber trees explains the presence of larger web-spinners. The Dominican trees are long, thin and smooth whereas the Baltic trees are wide and bushy, providing a much better environment for web-spinners to prosper," says Dr Penney.

The study demonstrates for the first time that spiders trapped in amber can be scientifically compared across deep time (30 million years). This is due to the fact that until now it was unknown whether the amber resins were trapping organisms uniformly. This study proves they were.

SOURCE: EUREKALERT

Men are the same as women.... just inside out !!
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: JimBob on 06/03/2006 03:19:11
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi38.photobucket.com%2Falbums%2Fe111%2Fgeezer69%2FScience%2F060303204735.jpg&hash=26a593a46a2a2cf43ae86b1238e591ae)

Largest Crater In The Great Sahara Discovered By Boston University Scientists



Researchers from Boston University have discovered the remnants of the largest crater of the Great Sahara of North Africa, which may have been formed by a meteorite impact tens of millions of years ago. Dr. Farouk El-Baz made the discovery while studying satellite images of the Western Desert of Egypt with his colleague, Dr. Eman Ghoneim, at BU's Center for Remote Sensing.

The double-ringed crater – which has an outer rim surrounding an inner ring – is approximately 31 kilometers in diameter. Prior to the latest finding, the Sahara's biggest known crater, in Chad, measured just over 12 kilometers. According to El-Baz, the Center's director, the crater’s vast area suggests the location may have been hit by a meteorite the entire size of the famous Meteor (Barringer) Crater in Arizona which is 1.2 kilometers wide.

El-Baz named his find “Kebira,” which means “large” in Arabic and also relates to the crater’s physical location on the northern tip of the Gilf Kebir region in southwestern Egypt. The reason why a crater this big had never been found before is something the scientists are speculating.

“Kebira may have escaped recognition because it is so large – equivalent to the total expanse of the Cairo urban region from its airport in the northeast to the Pyramids of Giza in the southwest,” said Dr. El-Baz. “Also, the search for craters typically concentrates on small features, especially those that can be identified on the ground. The advantage of a view from space is that it allows us to see regional patterns and the big picture.”

The researchers also found evidence that Kebira suffered significant water and wind erosion which may have helped keep its features unrecognizable to others. “The courses of two ancient rivers run through it from the east and west,” added Ghoneim.

The terrain in which the crater resides is composed of 100 million year-old sandstone – the same material that lies under much of the eastern Sahara. The researchers hope that field investigations and samples of the host rock will help in determining the exact age of the crater and its surroundings.

Kebira's shape is reminiscent of the many double-ringed craters on the Moon, which Dr. El-Baz remembers from his years of work with the Apollo program. Because of this, he believes the crater will figure prominently in future research in comparative planetology. And, since its shape points to an origin of extraterrestrial impact, it will likely prove to be the event responsible for the extensive field of “Desert Glass” – yellow-green silica glass fragments found on the desert surface between the giant dunes of the Great Sand Sea in southwestern Egypt.

Dr. El-Baz is research professor and Director of the Center for Remote Sensing at Boston University. He is a renowned geologist who over the past 30 years has conducted studies in all the major deserts of the world. He is a member of the U.S. National Academy of Engineering and a Fellow of the American Association for the Advancement of Sciences and the Geological Society of America. The latter established the “Farouk El-Baz Award for Desert Research” to reward excellence in arid land studies.

Dr. Eman Ghoneim is a research associate at the Center for Remote Sensing. She is an expert in hydrological modeling and now conducts research on arid land geomorphology with emphasis on groundwater concentration under the direction of Dr. El-Baz.

The Boston University Center for Remote Sensing is a research facility that was established in 1986. Researchers at the Center apply techniques of remote sensing and geographic information systems (GIS) to research in the fields of archaeology, geography and geology. In 1997, the Center was recognized by NASA as a “Center of Excellence in Remote Sensing.”

Founded in 1839, Boston University is an internationally recognized institution of higher education and research. With more than 30,000 students, it is the fourth largest independent university in the United States. BU contains 17 colleges and schools along with a number of multi-disciplinary centers and institutes, which are central to the school’s research and teaching mission.

http://www.sciencedaily.com/releases/2006/03/060303204735.htm
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 06/03/2006 20:43:56
Thanks JimBob...excellent post...keep em coming !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: DoctorBeaver on 06/03/2006 21:08:24
quote:
Originally posted by ariel

Beaver or Otter, It Lived in Dinosaurs' Time

(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fgraphics8.nytimes.com%2Fimages%2F2006%2F02%2F23%2Fscience%2F24beav184.jpg&hash=42569e7206fb2ba7087d2be3f2379b39)By JOHN NOBLE WILFORD




(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fwww.geocities.com%2Fdr_castor_fiber%2FBeaver01.jpg&hash=5b4c68e00b50bcfa94d84051dd6382e5)

Oh come on, no way is that 1st pic a beaver. Any fool can see the difference!
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 07/03/2006 20:11:24
This is an article which the esteemed DoctorBeaver posted as a separate thread..I thought it would be good here too..thanks Doctor Castor Fiber !!

----------------------------------

DARPA (Defense Advanced Research Project Agency)
has taken another page from science fiction writer William Gibson's book by creating a neural implant to enable engineers to remotely manipulate a shark's brain signals. This would eventually allow them to control the animal's movements and possibly decode their perceptions.

Given that sharks have senses that humans don't have (like the ability to sense electromagnetic fields), it could open up some interesting uses.

The implant consists of multi-channel neural ensemble readers and stimulators, diverse controllers and sensors. In addition, the DARPA researchers want to use their setup to detect and decipher the neural patterns that correspond to shark activities like sensing an ocean current, a particular scent in the water or an electrical field. If they can succeed in these experiments, it might be possible to control a free-swimming shark; it could be trained to track enemy ships or submarines, or to detect underwater mines or cables.

In the abstract for their presentation to the 2006 Ocean Sciences Meeting in Honolulu, Hawaii, the Naval Undersea Warfare Center summarized the implant in the following way:

NUWC is developing a fish tag whose goal is attaining behavior control of host animals via neural implants. This talk discusses a shark tag ... intended for long-term open ocean field efforts investigating viability of animal behavior control and its utility for networked sensing and data acquisition. The tag is centered on a multi-channel neural ensemble reader, a processor to interpret the readings in real-time, and a multi-channel stimulator, intended for both micro and macro stimulation.
(From Autonomous Shark Tag with Neural Reading and Stimulation Capability for Open-ocean Experiments)
In his 1981 short story Johnny Mnemonic, author William Gibson wrote about Jones, a military surplus dolphin cyborg that has equipment that is surprisingly similar to the DARPA sharks.

He rose out of the water, showing us the crusted plates along his sides, a kind of visual pun, his grace nearly lost under armor, clumsy and prehistoric. Twin deformities on either side of his skull had been engineered to house sensor units. Silver lesions gleamed on exposed sections of his gray-white hide.
(Read more about William Gibson's cyborg dolphin)
Of course, there is only so much you can do with a friendly dolphin. Maybe that's why DARPA's military sponsors have chosen sharks. Take a look at these related stories about scientists who have used implants to 'jack' into a cat's brain to see what the cat is seeing, or other researchers who have implanted RFID chips in birds to warn of Avian flu.



Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 07/03/2006 20:45:54
World's oldest ship timbers found in Egyptian desert

The oldest remains of seafaring ships in the world have been found in caves at the edge of the Egyptian desert along with cargo boxes that suggest ancient Egyptians sailed nearly 1,000 miles on rough waters to get treasures from a place they called God's Land, or Punt.
Florida State University anthropology professor Cheryl Ward has determined that wooden planks found in the manmade caves are about 4,000 years old - making them the world's most ancient ship timbers. Shipworms that had tunneled into the planks indicated the ships had weathered a long voyage of a few months, likely to the fabled southern Red Sea trading center of Punt, a place referenced in hieroglyphics on empty cargo boxes found in the caves, Ward said.

"The archaeological site is like a mothballed military base, and the artifacts there tell a story of some of the best organized administrators the world has ever seen," she said. "It's a site that has kept its secrets for 40 centuries."

Ward, an expert on ancient shipbuilding who previously was a member of famed Titanic explorer Robert Ballard's Black Sea project team, joined archaeologists Kathryn Bard of Boston University and Rodolfo Fattovich of the University of Naples l'Orientale as the chief maritime archaeologist at the site, a sand-covered bluff along the Red Sea called Wadi Gawasis, in December. The project, which Ward will detail in an upcoming issue of the International Journal of Nautical Archaeology, was conducted with the support of Zahi Hawass, secretary-general of Egypt's Supreme Council of Antiquities.

Scholars have long known that Egyptians traveled to Punt but they have debated its exact location and whether the Egyptians reached Punt by land or by sea. Some had thought the ancient Egyptians did not have the naval technology to travel long distances by sea, but the findings at the Wadi Gawasis confirm that Egyptians sailed a 2,000-mile round trip voyage to Punt, putting it in what is today Ethiopia or Yemen, Ward said.

The Wadi Gawasis site, located about 13 miles south of the modern city of Port Safaga, was an industrial shipyard of sorts with six rock-cut caves that the ancient Egyptians used as work and storage rooms to protect their equipment from the harsh desert conditions, Ward said. Along with timber and cargo boxes, the archaeologists found large stone anchors, shards of storage jars and more than 80 perfectly preserved coils of rope in the caves that had been sealed off until the next expedition - one that obviously never came.

The team also found a stela, or limestone tablet, of Pharaoh Amenemhat III, who ruled between 1844-1797 B.C., inscribed with all five of his royal names. The plaque provided further evidence that discoveries found at the site date to Egypt's Middle Kingdom period. A period of civil unrest and political instability likely put a halt to further exploration, Ward said, and the Wadi Gawasis site was long forgotten.

While in use, though, the ancient shipyard was central to a sophisticated government operation for the expeditions to Punt that Ward likened to NASA's space program. She theorized that ships were originally built at a Nile shipyard, then disassembled and carried across 90 miles of desert to the Red Sea, where they were put back together and launched on the voyage.

Upon the fleet's return several months later, the crews unloaded the cargo and began breaking down the ship piece by piece. Shipwrights inspected the vessels and marked unsatisfactory pieces with red paint. Others were cleaned, rid of shipworm and recycled. As many as 3,700 men may have taken part in the expeditions.

"The scale of the organization astounds me," Ward said. "They had men carry kits with pieces 10 feet long and 8 to 12 inches thick across the desert to reassemble into ships on the edge of a sea that is still difficult to sail today. To have the manpower and supply line to equip the shipyard there and sail five or so ships on the Red Sea, and to have the knowledge to use the currents and winds to return safely, would be tough today, and they achieved it without GPS, cell phones or computers, not to mention the combustion engine."

Ward will return to the Wadi Gawasis site next year to continue to excavate and record ship timbers and the ship assembly and break-up process and to reconstruct the vessels as they were originally configured.

SOURCE:EUREKALERT.ORG


Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 09/03/2006 19:46:01
Scientists piece together the most distant explosion
PENN STATE UNIVERSITY NEWS RELEASE
Posted: March 8, 2006

It came from the edge of the visible universe, the most distant explosion ever detected.

In this week's issue of Nature, scientists at Penn State University and their U.S. and European colleagues discuss how this explosion, detected on 4 September 2005, was the result of a massive star collapsing into a black hole.

The explosion, called a gamma-ray burst, comes from an era soon after stars and galaxies first formed, about 500 million to 1 billion years after the Big Bang. The universe is now 13.7 billion years old, so the September burst serves as a probe to study the conditions of the early universe.

"This was a massive star that lived fast and died young," said David Burrows, senior scientist and professor of astronomy and astrophysics at Penn State, a co-author on one of the three reports about this explosion published this week in Nature. "This star was probably quite different from the kind we see today, the type that only could have existed in the early universe."

The burst, named GRB 050904 after the date it was spotted, was detected by NASA's Swift satellite, which is operated by Penn State. Swift provided the burst coordinates so that other satellites and ground-based telescopes could observe the burst. Bursts typically last only 10 seconds, but the afterglow will linger for a few days.

GRB 050904 originated 13 billion light years from Earth, which means it occurred 13 billion years ago, for it took that long for the light to reach us. Scientists have detected only a few objects more than 12 billion light years away, so the burst is extremely important in understanding the universe beyond the reach of the largest telescopes.

"Because the burst was brighter than a billion suns, many telescopes could study it even from such a huge distance," said Burrows, whose analysis focuses mainly on Swift data from its three telescopes, covering a range of gamma-rays, X-rays, and ultraviolet/optical wavelengths, respectively. Burrows is the lead scientist for Swift's X-ray telescope.

The Swift team found several unique features in GRB 050904. The burst was long, lasting about 500 seconds; and the tail end of the burst exhibited multiple flares. These characteristics imply that the newly created black hole didn't form instantly, as some scientists have thought, but rather it was a longer, chaotic event.

Closer gamma-ray bursts do not have as much flaring, implying that the earliest black holes may have formed differently from ones in the modern era, Burrows said. The difference could be because the first stars were more massive than modern stars. Or, it could be the result of the environment of the early universe when the first stars began to convert hydrogen and helium (created in the Big Bang) into heavier elements.

GRB 050904, in fact, shows hints of newly minted heavier elements, according to data from ground-based telescopes. This discovery is the subject of a second Nature article by a Japanese group led by Nobuyuki Kawai at the Tokyo Institute of Technology.

GRB 050904 also exhibited time dilation, a result of the vast expansion of the universe during the 13 billion years that it took the light to reach us on Earth. This dilation results in the light appearing much redder than when it was emitted in the burst, and it also alters our perception of time as compared to the burst's internal clock.

These factors worked in the scientists' favor. The Penn State team turned Swift's instruments onto the burst about 2 minutes after the event began. The burst, however, was evolving as if it were in slow-motion and was only about 23 seconds into the bursting. So scientists could see the burst at a very early stage.

Only one quasar has been discovered at a greater distance. Yet, whereas quasars are supermassive black holes containing the mass of billions of stars, this burst comes from a single star. The detection of GRB 050904 confirms that massive stars mingled with the oldest quasars. It also confirms that even more distant star explosions -- perhaps from the first stars, theorists say--can be studied through a combination of observations with Swift and other world-class telescopes.

"We designed Swift to look for faint bursts coming from the edge of the universe," said Neil Gehrels of NASA Goddard Space Flight Center in Greenbelt, Md., Swift's principal investigator. "Now we've got one and it's fascinating. For the first time we can learn about individual stars from near the beginning of time. There are surely many more out there."

Swift was launched in November 2004 and was fully operational by January 2005. Swift carries three main instruments: the Burst Alert Telescope, the X-ray Telescope, and the Ultraviolet/Optical Telescope. Swift's gamma-ray detector, the Burst Alert Telescope, provides the rapid initial location and was built primarily by the NASA Goddard Space Flight Center in Greenbelt and Los Alamos National Laboratory and constructed at GSFC. Swift's X-Ray Telescope and UV/Optical Telescope were developed and built by international teams led by Penn State and drew heavily on each institution's experience with previous space missions. The X-ray Telescope resulted from Penn State's collaboration with the University of Leicester in England and the Brera Astronomical Observatory in Italy. The Ultraviolet/Optical Telescope resulted from Penn State's collaboration with the Mullard Space Science Laboratory of the University College-London. These three telescopes give Swift the ability to do almost immediate follow-up observations of most gamma-ray bursts because Swift can rotate so quickly to point toward the source of the gamma-ray signal.


SOURCE: SPACEFLIGHTNOW.COM

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 10/03/2006 13:58:30
Mass Extinctions - A Threat from Outer Space or Our Own Planet's Detox?
University scientists suggest extraterrestrial theories are flawed and that more down to earth factors could have accounted for past mass extinctions

Earth history has been punctuated by several mass extinctions rapidly wiping out nearly all life forms on our planet. What causes these catastrophic events? Are they really due to meteorite impacts? Current research suggests that the cause may come from within our own planet – the eruption of vast amounts of lava that brings a cocktail of gases from deep inside the Earth and vents them into the atmosphere.

University of Leicester geologists, Professor Andy Saunders and Dr Marc Reichow, are taking a fresh look at what may actually have wiped out the dinosaurs 65 million years ago and caused other similarly cataclysmic events, aware they may end up exploding a few popular myths.

The idea that meteorite impacts caused mass extinctions has been in vogue over the last 25 years, since Louis Alverez’s research team in Berkeley, California published their work about an extraterrestrial iridium anomaly found in 65-million-year-old layers at the Cretaceous-Tertiary boundary. This anomaly only could be explained by an extraterrestrial source, a large meteorite, hitting the Earth and ultimately wiping the dinosaurs – and many other organisms - off the Earth’s surface.

Professor Saunders commented:

    “Impacts are suitably apocalyptic. They are the stuff of Hollywood. It seems that every kid’s dinosaur book ends with a bang. But are they the real killers and are they solely responsible for every mass extinction on earth? There is scant evidence of impacts at the time of other major extinctions e.g., at the end of the Permian, 250 million years ago, and at the end of the Triassic, 200 million years ago. The evidence that has been found does not seem large enough to have triggered an extinction at these times.”

Flood basalt eruptions are – he says - an alternative kill mechanism. These do correspond with all main mass extinctions, within error of the techniques used to determine the age of the volcanism. Furthermore, they may have released enough greenhouse gases (SO2 and CO2) to dramatically change the climate. The largest flood basalts on Earth (Siberian Traps and Deccan Traps) coincide with the largest extinctions (end-Permian, and end-Cretaceous). “Pure coincidence?”, ask Saunders and Reichow.

While this is unlikely to be pure chance, the Leicester researchers are interested in precisely what the kill mechanism may be. One possibility is that the gases released by volcanic activity lead to a prolonged volcanic winter induced by sulphur-rich aerosols, followed by a period of CO2-induced warming.

Professor Andy Saunders and Dr. Marc Reichow at Leicester, in collaboration with Anthony Cohen, Steve Self, and Mike Widdowson at the Open University, have recently been awarded a NERC (Natural Environment Research Council) grant to study the Siberian Traps and their environmental impact.

The Siberian Traps are the largest known continental flood basalt province. Erupted about 250 million years ago at high latitude in the northern hemisphere, they are one of many known flood basalts provinces - vast outpourings of lava that covered large areas of the Earth's surface. A major debate is underway concerning the origin of these provinces –including the Siberian Traps - and their environmental impact.

Using radiometric dating techniques, they hope to constrain the age and, combined with geochemical analysis, the extent, of the Siberian Traps. Measuring how much gas was released during these eruptions 250 million years ago is a considerable challenge. The researchers will study microscopic inclusions trapped in minerals of the Siberian Traps rocks to estimate the original gas contents. Using these data they hope to be able to assess the amount of SO2 and CO2 released into the atmosphere 250 million years ago, and whether or not this caused climatic havoc, wiping out nearly all life on earth. By studying the composition of sedimentary rocks laid down at the time of the mass extinction, they also hope to detect changes to seawater chemistry that resulted from major changes in climate.

From these data Professor Saunders and his team hope to link the volcanism to the extinction event. He explained:

    “If we can show, for example, that the full extent of the Siberian Traps was erupted at the same time, we can be confident that their environmental effects were powerful. Understanding the actual kill mechanism is the next stage….watch this space.”

SOURCE: UNIVERSITY OF LEICESTER PRESS RELEASE

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: DoctorBeaver on 13/03/2006 18:18:35
Is it April 1st already? This is from AOL news March 13th, 2006

Never mind tilting trains or the end of slam doors, British Rail once entertained hopes of transporting passengers by nuclear-powered "flying saucer'', it has emerged.
Rail managers filed an application for a patent in December 1970 for a space vehicle powered by "controlled thermonuclear fusion reaction ignited by one or more pulsed laser beams''.
The space vehicle, with its passenger compartment upstairs, like the pod of a jumbo jet, would have been cheap to run and super-fast, according to inventor Charles Osmond Frederick.
The detailed plans, made on behalf of the British Railways Board, were found on the European Patent Office Web site with the patent granted in March 1973.
A patent document reads: "The present invention relates to a space vehicle. More particularly it relates to a power supply for a space vehicle which offers a source of sustained thrust for the loss of a very small mass of fuel.
"Thus it would enable very high velocities to be attained in a space vehicle and in fact the prolonged acceleration of the vehicle may in some circumstances be used to simulate gravity.''
The high-tech world envisaged by rail bosses failed to go further than the drawing board. The patent lapsed because of non-payment of renewal fees.
Space experts dismissed the design as a pure science fiction and based on a fusion process that does not exist yet.
Michel van Baal, of the European Space Agency in the Netherlands told The Times: "I have had a look at the plans and they don't look very serious to me at all."


Brand new forum
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More than just science
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 16/03/2006 20:26:27
River of stars streams across the northern sky
CALTECH NEWS RELEASE
Posted: March 15, 2006

Astronomers have discovered a narrow stream of stars extending at least 45 degrees across the northern sky. The stream is about 76,000 light-years distant from Earth and forms a giant arc over the disk of the Milky Way galaxy.


An artist's depiction of the river of stars. On an evening in early April, the new stream rises 45 degrees from the eastern horizon, passing just under the bowl of the Big Dipper. The North Star Polaris is at far left. Credit: Caltech
 
 
In the March issue of the Astrophysical Journal Letters, Carl Grillmair, an associate research scientist at the California Institute of Technology's Spitzer Science Center, and Roberta Johnson, a graduate student at California State University Long Beach, report on the discovery.

"We were blown away by just how long this thing is," says Grillmair. "As one end of the stream clears the horizon this evening, the other will already be halfway up the sky."

The stream begins just south of the bowl of the Big Dipper and continues in an almost straight line to a point about 12 degrees east of the bright star Arcturus in the constellation Bootes. The stream emanates from a cluster of about 50,000 stars known as NGC 5466.

The newly discovered stream extends both ahead and behind NGC 5466 in its orbit around the galaxy. This is due to a process called tidal stripping, which results when the force of the Milky Way's gravity is markedly different from one side of the cluster to the other. This tends to stretch the cluster, which is normally almost spherical, along a line pointing towards the galactic center.

At some point, particularly when its orbit takes it close to the galactic center, the cluster can no longer hang onto its most outlying stars, and these stars drift off into orbits of their own. The lost stars that find themselves between the cluster and the galactic center begin to move slowly ahead of the cluster in its orbit, while the stars that drift outwards, away from the galactic center, fall slowly behind.

Ocean tides are caused by exactly the same phenomenon, though in this case it's the difference in the moon's gravity from one side of Earth to the other that stretches the oceans. If the gravity at the surface of Earth were very much weaker, then the oceans would be pulled from the planet, just like the stars in NGC 5466's stream.

Despite its size, the stream has never previously been seen because it is so completely overwhelmed by the vast sea of foreground stars that make up the disk of the Milky Way. Grillmair and Johnson found the stream by examining the colors and brightnesses of more than nine million stars in the Sloan Digital Sky Survey public database.

"It turns out that, because they were all born at the same time and are situated at roughly the same distance, the stars in globular clusters have a fairly unique signature when you look at how their colors and brightnesses are distributed," says Grillmair.

Using a technique called matched filtering, Grillmair and Johnson assigned to each star a probability that it might once have belonged to NGC 5466. By looking at the distribution of these probabilities across the sky, "the stream just sort of reached out and smacked us.

"The new stream may be even longer than we know, as we are limited at the southern end by the extent of the currently available data," he adds. "Larger surveys in the future should be able to extend the known length of the stream substantially, possibly even right around the whole sky."

The stars that make up the stream are much too faint to be seen by the unaided human eye. Owing to the vast distances involved, they are about three million times fainter than even the faintest stars that we can see on a clear night.

Grillmair says that such discoveries are important for our understanding of what makes up the Milky Way galaxy. Like earthbound rivers, such tidal streams can tell us which way is "down," how steep is the slope, and where the mountains and valleys are located.

By measuring the positions and velocities of the stars in these streams, astronomers hope to determine how much "dark matter" the Milky Way contains, and whether the dark matter is distributed smoothly, or in enormous orbiting chunks.


Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 20/03/2006 14:59:22
" Wasp performs roach-brain-surgery to make zombie slave-roaches

Ampulex compressa is a wasp that has evolved to tackle roaches, insert a stinger into their brains and disable their escape reflexes. This lets the wasp use the roach's antennae to steer the roach to its lair, where it can lay its egg in it. "Parasite Rex" author Carl Zimmer tells the story in gooey, graphic detail:
The wasp slips her stinger through the roach's exoskeleton and directly into its brain. She apparently use sensors along the sides of the stinger to guide it through the brain, a bit like a surgeon snaking his way to an appendix with a laparoscope. She continues to probe the roach's brain until she reaches one particular spot that appears to control the escape reflex. She injects a second venom that influences these neurons in such a way that the escape reflex disappears.
From the outside, the effect is surreal. The wasp does not paralyze the cockroach. In fact, the roach is able to lift up its front legs again and walk. But now it cannot move of its own accord. The wasp takes hold of one of the roach's antennae and leads it--in the words of Israeli scientists who study Ampulex--like a dog on a leash. "

http://www.boingboing.net/2006/02/03/wasp_performs_roachb.html

Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ariel on 23/03/2006 02:19:51
Old-World Primates Evolved Color Vision To Better See Each Other Blush, Study Reveals

Your emotions can easily be read by others when you blush--at least by others familiar with your skin color. What's more, the blood rushing out of your face when you're terrified is just as telling. And when it comes to our evolutionary cousins the chimpanzees, they not only can see color changes in each other's faces, but in each other's rumps as well.
Now, a team of California Institute of Technology researchers has published a paper suggesting that we primates evolved our particular brand of color vision so that we could subtly discriminate slight changes in skin tone due to blushing and blanching. The work may answer a long-standing question about why trichromat vision (that is, color via three cone receptors) evolved in the first place in primates.
"For a hundred years, we've thought that color vision was for finding the right fruit to eat when it was ripe," says Mark Changizi, a theoretical neurobiologist and postdoctoral researcher at Caltech. "But if you look at the variety of diets of all the primates having trichromat vision, the evidence is not overwhelming."
Reporting in the current issue of the journal Biology Letters, Changizi and his coauthors show that our color cones are optimized to be sensitive to subtle changes in skin tone due to varying amounts of oxygenated hemoglobin in the blood.
The spectral sensitivity of the color cones is somewhat odd, Changizi says. Bees, for example, have four color cones that are evenly spread across the visible spectrum, with the high-frequency end extending into the ultraviolet. Birds have three color cones that are also evenly distributed in the visible spectrum.
The old-world primates, by contrast, have an "S" cone at about 440 nanometers (the wavelength of visible light roughly corresponding to blue light), an "M" cone sensitive at slightly less than 550 nanometers, and an "L" cone sensitive at slightly above 550 nanometers.
"This seems like a bad idea to have two cones so close together," Changizi says. "But it turns out that the closeness of the M and L cone sensitivities allows for an additional dimension of sensitivity to spectral modulation. Also, their spacing maximizes sensitivity for discriminating variations in blood oxygen saturation." As a result, a very slight lowering or rising of the oxygen in the blood is easily discriminated by any primate with this type of cone arrangement.
In fact, trichromat vision is sensitive not only for the perception of these subtle changes in color, but also for the perception of the absence or presence of blood. As a result, primates with trichromat vision are not only able to tell if a potential partner is having a rush of emotion due to the anticipation of mating, but also if an enemy's blood has drained out of his face due to fear.
"Also, ecologically, when you're more oxygenated, you're in better shape," Changizi adds, explaining that a naturally rosy complexion might be a positive thing for purposes of courtship.
Adding to the confidence of the hypothesis is the fact that the old-world trichromats tend to be bare-faced and bare-butted as well. "There's no sense in being able to see the slight color variations in skin if you can't see the skin," Changizi says. "And what we find is that the trichromats have bare spots on their faces, while the dichromats have furry faces."
"This could connect up with why we're the 'naked ape,'" he concludes. The few human spots that are not capable of signaling, because they are in secluded regions, tend to be hairy-such as the top of the head, the armpits, and the crotch. And when the groin occasionally does tend to exhibit bare skin, it occurs in circumstances in which a potential mate may be able to see that region.
"Our speculation is that the newly bare spots are for color signaling."

http://www.sciencedaily.com/releases/2006/03/060320221839.htm


(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi11.photobucket.com%2Falbums%2Fa196%2Fbariel%2Ffsm.jpg&hash=27b1c6663feeeee1f95650d42cca0927) ariel
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 27/03/2006 01:42:51
Mass extinctions – a threat from outer space or our own planet's detox?


University of Leicester scientists suggest extraterrestrial theories are flawed and that more down to earth factors could have accounted for past mass extinctions
Earth history has been punctuated by several mass extinctions rapidly wiping out nearly all life forms on our planet. What causes these catastrophic events? Are they really due to meteorite impacts? Current research suggests that the cause may come from within our own planet – the eruption of vast amounts of lava that brings a cocktail of gases from deep inside the Earth and vents them into the atmosphere.
University of Leicester geologists, Professor Andy Saunders and Dr Marc Reichow, are taking a fresh look at what may actually have wiped out the dinosaurs 65 million years ago and caused other similarly cataclysmic events, aware they may end up exploding a few popular myths.

The idea that meteorite impacts caused mass extinctions has been in vogue over the last 25 years, since Louis Alverez's research team in Berkeley, California published their work about an extraterrestrial iridium anomaly found in 65-million-year-old layers at the Cretaceous-Tertiary boundary. This anomaly only could be explained by an extraterrestrial source, a large meteorite, hitting the Earth and ultimately wiping the dinosaurs – and many other organisms - off the Earth's surface.

Professor Saunders commented: "Impacts are suitably apocalyptic. They are the stuff of Hollywood. It seems that every kid's dinosaur book ends with a bang. But are they the real killers and are they solely responsible for every mass extinction on earth? There is scant evidence of impacts at the time of other major extinctions e.g., at the end of the Permian, 250 million years ago, and at the end of the Triassic, 200 million years ago. The evidence that has been found does not seem large enough to have triggered an extinction at these times."

Flood basalt eruptions are – he says - an alternative kill mechanism. These do correspond with all main mass extinctions, within error of the techniques used to determine the age of the volcanism. Furthermore, they may have released enough greenhouse gases (SO2 and CO2) to dramatically change the climate. The largest flood basalts on Earth (Siberian Traps and Deccan Traps) coincide with the largest extinctions (end-Permian, and end-Cretaceous). "Pure coincidence?", ask Saunders and Reichow.

While this is unlikely to be pure chance, the Leicester researchers are interested in precisely what the kill mechanism may be. One possibility is that the gases released by volcanic activity lead to a prolonged volcanic winter induced by sulphur-rich aerosols, followed by a period of CO2-induced warming.

Professor Andy Saunders and Dr. Marc Reichow at Leicester, in collaboration with Anthony Cohen, Steve Self, and Mike Widdowson at the Open University, have recently been awarded a NERC (Natural Environment Research Council) grant to study the Siberian Traps and their environmental impact.

The Siberian Traps are the largest known continental flood basalt province. Erupted about 250 million years ago at high latitude in the northern hemisphere, they are one of many known flood basalts provinces - vast outpourings of lava that covered large areas of the Earth's surface. A major debate is underway concerning the origin of these provinces –including the Siberian Traps - and their environmental impact.

Using radiometric dating techniques, they hope to constrain the age and, combined with geochemical analysis, the extent, of the Siberian Traps. Measuring how much gas was released during these eruptions 250 million years ago is a considerable challenge. The researchers will study microscopic inclusions trapped in minerals of the Siberian Traps rocks to estimate the original gas contents. Using these data they hope to be able to assess the amount of SO2 and CO2 released into the atmosphere 250 million years ago, and whether or not this caused climatic havoc, wiping out nearly all life on earth. By studying the composition of sedimentary rocks laid down at the time of the mass extinction, they also hope to detect changes to seawater chemistry that resulted from major changes in climate.

From these data Professor Saunders and his team hope to link the volcanism to the extinction event. He explained: "If we can show, for example, that the full extent of the Siberian Traps was erupted at the same time, we can be confident that their environmental effects were powerful. Understanding the actual kill mechanism is the next stage….watch this space."

SOURCE: EUREKALERT.ORG



Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 29/03/2006 18:07:10
Mars meteorite similar to bacteria-etched Earth rocks
OREGON STATE UNIVERSITY NEWS RELEASE
Posted: March 28, 2006

A new study of a meteorite that originated from Mars has revealed a series of microscopic tunnels that are similar in size, shape and distribution to tracks left on Earth rocks by feeding bacteria.

And though researchers were unable to extract DNA from the Martian rocks, the finding nonetheless adds intrigue to the search for life beyond Earth.

Results of the study were published in the latest edition of the journal Astrobiology.

Martin Fisk, a professor of marine geology in the College of Oceanic and Atmospheric Sciences at Oregon State University and lead author of the study, said the discovery of the tiny burrows do not confirm that there is life on Mars, nor does the lack of DNA from the meteorite discount the possibility.

"Virtually all of the tunnel marks on Earth rocks that we have examined were the result of bacterial invasion," Fisk said. "In every instance, we've been able to extract DNA from these Earth rocks, but we have not yet been able to do that with the Martian samples.

"There are two possible explanations," he added. "One is that there is an abiotic way to create those tunnels in rock on Earth, and we just haven't found it yet. The second possibility is that the tunnels on Martian rocks are indeed biological in nature, but the conditions are such on Mars that the DNA was not preserved."

More than 30 meteorites that originated on Mars have been identified. These rocks from Mars have a unique chemical signature based on the gases trapped within. These rocks were "blasted off" the planet when Mars was struck by asteroids or comets and eventually these Martian meteorites crossed Earth's orbit and plummeted to the ground.

One of these is Nakhla, which landed in Egypt in 1911, and provided the source material for Fisk's study. Scientists have dated the igneous rock fragment from Nakhla - which weighs about 20 pounds - at 1.3 billion years in age. They believe that the rock was exposed to water about 600 million years ago, based on the age of clay found inside the rocks.

"It is commonly believed that water is a necessary ingredient for life," Fisk said, "so if bacteria laid down the tunnels in the rock when the rock was wet, they may have died 600 million years ago. That may explain why we can't find DNA - it is an organic compound that can break down."

Other authors on the paper include Olivia Mason, an OSU graduate student; Radu Popa, of Portland State University; Michael Storrie-Lombardi, of the Kinohi Institute in Pasadena, Calif.; and Edward Vicenci, from the Smithsonian Institution.

Fisk and his colleagues have spent much of the past 15 years studying microbes that can break down igneous rock and live in the obsidian-like volcanic glass. They first identified the bacteria through their signature tunnels then were able to extract DNA from the rock samples - which have been found in such diverse environments on Earth as below the ocean floor, in deserts and on dry mountaintops.

They even found bacteria 4,000 feet below the surface in Hawaii that they reached by drilling through solid rock.

In all of these Earth rock samples that contain tunnels, the biological activity began at a fracture in the rock or the edge of a mineral where the water was present. Igneous rocks are initially sterile because they erupt at temperatures exceeding 1,000 degrees C. - and life cannot establish itself until the rocks cool. Bacteria may be introduced into the rock via dust or water, Fisk pointed out.

"Several types of bacteria are capable of using the chemical energy of rocks as a food source," he said. "One group of bacteria in particular is capable of getting all of its energy from chemicals alone, and one of the elements they use is iron - which typically comprises 5 to 10 percent of volcanic rock."

Another group of OSU researchers, led by microbiologist Stephen Giovannoni, has collected rocks from the deep ocean and begun developing cultures to see if they can replicate the rock-eating bacteria. Similar environments usually produce similar strains of bacteria, Fisk said, with variable factors including temperature, pH levels, salt levels, and the presence of oxygen.

The igneous rocks from Mars are similar to many of those found on Earth, and virtually identical to those found in a handful of environments, including a volcanic field found in Canada.

One question the OSU researchers hope to answer is whether the bacteria begin devouring the rock as soon as they are introduced. Such a discovery would help them estimate when water - and possibly life - may have been introduced on Mars

SOURCE: SPACEFLIGHTNOW.COM


Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 30/03/2006 18:47:20
Preserved in crystal

Scientists at the Weizmann Institute of Science recently discovered a new source of well-preserved ancient DNA in fossil bones. Their findings were published in the Proceedings of the National Academy of Sciences (PNAS).
Fossil DNA is a potential source of information on the evolution, population dynamics, migrations, diets and diseases of animals and humans. But if it is not well preserved or becomes contaminated by modern DNA, the results are uninterpretable.

The scientists, Prof. Steve Weiner and Michal Salamon of the Institute's Structural Biology Department, working in collaboration with Profs. Baruch Arensburg, Tel Aviv University, and Noreen Tuross, Harvard University, may have found a way to overcome these problems.

It was in 1986 that Weiner first reported the existence of crystal clusters in fresh bones. Even when these bones are ground up and treated with sodium hypochlorite – a substance that removes all traces of organic matter – the clusters of crystals remain intact and the organic material embedded in them is unaffected. Now, almost 20 years later, Weiner and Salamon have returned to these findings, reasoning that fossil bones might possess such crystal structures containing preserved ancient DNA.

After treating two modern and six fossil animal bones with the sodium hypo-chlorite, they found that DNA could be extracted from most of these crystal aggregates that is better preserved and contains longer fragments than DNA from untreated ground bone. The technique for reading the DNA worked better, as well, and the use of sodium hypochlorite reduces the possibility of modern contamination.

The crystal aggregates act as a "privileged niche in fossil bone," protecting the DNA from hostile environments and leaving it relatively undamaged over time. The team's findings suggest that the DNA in these aggregates should be preferred, whenever possible, over DNA from untreated bone.

This method holds much promise for the future analysis of ancient DNA in bones in yielding more reliable and authentic results than has previously been possible, and may help in unearthing the mysteries of our ancestral past.


SOURCE: EUREKALERT.ORG

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 01/04/2006 15:01:06
XXL from Too Few Zs? Skimping on sleep might cause obesity, diabetes
Ben Harder

Widespread sleep deprivation could partly explain the current epidemics of both obesity and diabetes, emerging data suggest.

Too little sleep may contribute to long-term health problems by changing the concentrations of hormones that control appetite, increasing food intake, and disrupting the biological clock, according to Eve Van Cauter of the University of Chicago.

Van Cauter and other researchers discussed possible links between sleep deprivation, expanding waistlines, and obesity-related problems this week in Washington, D.C., at a meeting titled A Scientific Workshop on Sleep Loss and Obesity: Interacting Epidemics.

Researchers have observed that people who sleep less than 7 to 8 hours a night have elevated rates of obesity and diabetes. In late 2004, Karine Spiegel of the Free University of Brussels in Belgium and Van Cauter conducted experiments in healthy men showing that forced sleep restriction for 2 days increased appetite and triggered changes in the appetite-related hormones ghrelin and leptin.The observed ghrelin elevation and leptin suppression may have encouraged food intake, Spiegel says.

Before that pivotal study, tests had demonstrated that obesity could disrupt sleep, but few experiments had investigated whether lack of sleep could contribute to obesity.

Preliminary results close in on an independent relationship between sleep loss and diabetes. Spiegel, Van Cauter, and their colleagues collected data from 13 volunteers who habitually sleep about 5 hours per night and from 14 others who sleep about 8 hours per night. The groups had similar body weights and ages.

Spiegel reported at the conference that the people who sleep less produce markedly elevated quantities of the hormone insulin. Their high insulin production reflects a state, called insulin resistance, that can be a harbinger of diabetes, Spiegel says.

In another new study reported at the conference, Emmanuel Mignot of Stanford University Medical School and his colleagues tested about 2,000 employees of Wisconsin government agencies. Obesity was common in that population, and volunteers who slept either significantly less or more than the overall average tended to be heavier than people getting a moderate amount of sleep, Mignot reports. Compared with people who slept 8 hours a night, those who slept 5 hours had 16 percent lower leptin concentrations and 15 percent higher ghrelin concentrations in their blood.

Mignot and his colleagues have launched a yearlong trial that will test whether prescribing extra sleep can make some obese people lose weight. He hypothesizes that an extra 1.5 hours of sleep per night might produce weight losses of 3 to 4 percent.

But Van Cauter says that when her team previously asked patients to increase nightly sleep for extended periods of time, the changes in behavior lasted only a few days.

Short sleep might encourage overeating independent of its hormonal effects, says Mignot. "When people sleep less, they have more time for eating," he notes.


SOURCE: SCIENCENEWS.ORG

Oh Joy !!..lucky me !!...though the conclusion that if you're awake more means you'll eat more is obvious isn't it ?

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 01/04/2006 22:47:50
Google to advertise on the moon
VNUnet Saturday April 1, 09:00 AM

 
By Arif Pollo

In the most wide-scale advertising attempt ever known,Google plans to brand itslogo into the surface of the moon so that it is visible from Earth.

The search giant will pay the US government an estimated $1bn for the rightsto the lunar land.

"You've heard of GoogleMars and GoogleEarth, where we show you maps of those planets? Well this is Google Moon,where we become the world's biggest brand," said an unnamed source at thecompany.

The Americans were the first to lay claim to the moon back in July 1969 whenNeilArmstrong took "one small step for a man, one giant leap for mankind".

Planting the flag on the Moon's surface has always been considered a gestureof being there first, but that claim has now paid off in real money terms forthe US government.

Google announced this week that it would sell afurther 5.3 billion shares to raise $2.1bn.

Google's official filing to theSecurities and ExchangeCommission said that the sale of shares was designed to raise additionalcapital for future acquisitions, but the company declined to be morespecific about any current agreements or commitments.

Analysts speculated at the time that the company must have a major purchasein mind and it is now clear where the funds will be heading.

SOURCE: YAHOO.

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ariel on 05/04/2006 01:26:15
Study claims ice, not water, kept Jesus afloat


University professor attempts to explain miracles with science


Tuesday, April 4, 2006; Posted: 6:54 p.m. EDT (22:54 GMT)

MIAMI, Florida (Reuters) -- The New Testament says that Jesus walked on water, but a Florida university professor believes there could be a less miraculous explanation -- he walked on a floating piece of ice.

Professor Doron Nof also theorized in the early 1990s that Moses's parting of the Red Sea had solid science behind it.

Nof, a professor of oceanography at Florida State University, said on Tuesday that his study found an unusual combination of water and atmospheric conditions in what is now northern Israel could have led to ice formation on the Sea of Galilee.

Nof used records of the Mediterranean Sea's surface temperatures and statistical models to examine the dynamics of the Sea of Galilee, which Israelis know now as Lake Kinneret.

The study found that a period of cooler temperatures in the area between 1,500 and 2,600 years ago could have included the decades in which Jesus lived.

A drop in temperature below freezing could have caused ice -- thick enough to support a human -- to form on the surface of the freshwater lake near the western shore, Nof said. It might have been nearly impossible for distant observers to see a piece of floating ice surrounded by water.

Nof said he offered his study -- published in the April edition of the Journal of Paleolimnology -- as a "possible explanation" for Jesus' walk on water.

"If you ask me if I believe someone walked on water, no, I don't," Nof said. "Maybe somebody walked on the ice, I don't know. I believe that something natural was there that explains it."

"We leave to others the question of whether or not our research explains the biblical account."

When he offered his theory 14 years ago that wind and sea conditions could explain the parting of the Red Sea, Nof said he received some hate mail, even though he noted that the idea could support the biblical description of the event.

And as his theory of Jesus' walk on ice began to circulate, he had more hate mail in his e-mail inbox.

"They asked me if I'm going to try next to explain the resurrection," he said.



http://www.cnn.com/2006/TECH/science/04/04/jesus.science.reut/index.html

(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi11.photobucket.com%2Falbums%2Fa196%2Fbariel%2Ffsm.jpg&hash=27b1c6663feeeee1f95650d42cca0927) ariel
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: DoctorBeaver on 05/04/2006 12:11:16
Oh bugger, he's sussed me [:(!]

Brand new forum at
http://beaverlandforum.d4a.com
More than just science
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: JimBob on 07/04/2006 00:56:47
I bow in awe and reverence.

Jim

The mind is like a parachute. It works best when open.  -- A. Einstein
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 13/04/2006 17:58:19
" Testicle cells may aid research  
 
Stem cells hold the promise of many new treatments
Scientists believe the human testicle may provide a less controversial source of cells for stem cell research.
Stem cells hold great promise for new treatments for many conditions as they have the ability to become many different types of adult tissue.

But at present the most flexible type is found in human embryos - and their use is mired in controversy.

A German team describes in the journal Nature how it isolated cells from mice testes that seem equally useful.

  The possibility of using cells from the testes as an alternative to embryonic stem cells for therapy is intriguing

Scientists already knew certain cells in the testes of newborn mice were able, like embryonic stem cells, to generate numerous different tissue types.

But until now they had not been able to show the same cells existed in adults."

http://news.bbc.co.uk/1/hi/health/4841786.stm
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: JimBob on 21/04/2006 00:49:10

From http://www.eurekalert.org/pub_releases/2006-04/iodp-spf041906.php

Public release date: 20-Apr-2006

Contact: Nancy Light
nlight@iodp.org
202-465-7511
Integrated Ocean Drilling Program Management International

Scientists penetrate fossil magma chamber beneath intact ocean crust



-- achieving scientific 'first'
PACIFIC OCEAN, approximately 800 km west of Costa Rica¡ªAn international team of scientists aboard the research drilling ship JOIDES Resolution has¡--for the first time¡--recovered black rocks known as gabbros from intact ocean crust. Supported by the Integrated Ocean Drilling Program (IODP), the scientists drilled through the volcanic rock that forms the Earth's crust to reach a fossil magma chamber lying 1.4 kilometers beneath the seafloor.

"By sampling a complete section of the upper oceanic crust, we've achieved a goal scientists have pursued for over 40 years, since the days of Project MoHole," says Damon Teagle, National Oceanography Centre, University of Southampton, UK, and co-chief scientist of this drilling expedition. "Our accomplishment will ultimately help science answer the important question, 'how is new ocean crust formed?'"

Formation of ocean crust is a key process in the cycle of plate tectonics; it constantly 'repaves' the Earth's surface, builds mountains, and leads to earthquakes and volcanoes. Project MoHole, begun in the 1950s, aimed to drill all the way through the ocean crust, into the Earth's mantle.

Jeffrey Alt of the University of Michigan and co-chief scientist on an earlier leg of this mission, explains that "having this sample from the deep fossil magma chamber allows us to compare its composition to the overlying lavas. It will help explain," he says, "whether ocean crust, which is about six- to seven- kilometers thick, is formed from one high-level magma chamber, or from a series of stacked magma lenses." He emphasizes that "the size and geometry of the melt lens affects not only the composition and thermal structure of the ocean crust, but also the vigor of hydrothermal circulation of seawater through the crust." Alt states that such systems lead to spectacular black-smoker vents--modern analogs of ancient copper deposits and deep-ocean oases that support exotic life.

IODP Program Director James Allan at the U.S. National Science Foundation, which co-funds IODP research with Japan, further clarifies what the expedition's discovery represents. "These results," he says, "coming from the structural heart of Pacific crust, confirm ideas from seismologic interpretation about how fast-spreading oceanic crust is built. They refine our understanding of the relationship between seismic velocity and crustal rock composition, and open new vistas for investigating the origin of lower oceanic crust, best addressed by deeper drilling." NSF and Japan each provide a scientific drilling vessel to IODP for research teams.

Geophysical theories have long projected that oceanic magma chambers freeze to form coarse-grained, black rocks known as gabbros, commonly used for facing stones on buildings and kitchen countertops. Although gabbros have been sampled elsewhere in the oceans, where faulting and tectonic movement have brought them closer to the seafloor, this is the first time that gabbros have been recovered from intact ocean crust.

"Drilling this deep hole in the eastern Pacific is a rare opportunity to calibrate remote geophysical measurements such as seismic travel time or magnetic field with direct observations of real rocks," says geophysicist Doug Wilson, University of California, Santa Barbara. Co-chief scientist on an earlier expedition to the same drilling site, Wilson was instrumental in helping to select the site drilled. His contributed to the research mission thorough study of the ocean crust's magnetic properties.

"Finding the right place to drill was probably key to our success," Wilson asserts. The research team identified a 15-million-year-old region of the Pacific Ocean that formed when the East Pacific Rise was spreading at a 'superfast' rate (more than 200 millimeters per year), faster than any mid-ocean ridge on Earth today. "We planned to exploit a partially tested geophysical observation that magma chambers should be closest to the Earth's surface, in crust formed at the fastest spreading rate. If that theory were to be correct," reasoned Wilson, "then we should only need to drill a relatively shallow hole--compared to anywhere else--to reach gabbros." Wilson and colleagues proved the theory correct.

Following three years of research and multiple trips to the site in question, the borehole that rendered the magma chamber is now more than 1,500 meters deep; it took nearly five months at sea to drill. Twenty-five hardened steel and tungsten carbide drill bits were used before the scientists' work was complete. The rocks directly above the frozen magma chamber were extremely hard because they had been baked by the underlying magmas, much like tempered steel.

IODP scientists want to return to the site of the unearthed magma chamber to explore deeper, in hopes of finding more secrets hidden deep within the ocean's crust.

###


The Integrated Ocean Drilling Program (IODP) is an international marine research program dedicated to advancing scientific understanding of the Earth, the deep biosphere, climate change, and Earth processes by sampling and monitoring sub-seafloor environments. IODP is supported by two lead agencies: the U.S. National Science Foundation, and Japan's Ministry of Education, Culture, Sports, Science, and Technology, with support from a European consortium of 17 countries, and the People's Republic of China. IODP's U.S.-sponsored drilling operations are conducted by the JOI Alliance; comprised of the Joint Oceanographic Institutions, Texas A & M University Research Foundation, and Lamont-Doherty Earth Observatory of Columbia University.

To access a list of research participants on IODP Expedition 312 and the countries they represent, or to see photos from the expedition, go to http://iodp.tamu.edu/scienceops/expeditions/exp312.html.

Note to Editors: A paper authored by the IODP research party is to be published online in Science Express on April 20, 2006. To obtain a copy of the embargoed paper, contact AAAS Office of Public Programs, +1-202-326-6440 or scipak@aaas.org

CONTACTS:

Nancy Light, IODP Management International
Tel: 202-465-7511, 202-361-3325

Jon Corsiglia, Joint Oceanographic Institutions, JOI Alliance
Tel: 202-232-3900 ext. 1644

Cheryl Dybas, U.S. National Science Foundation
Tel: 703-292-7734



The mind is like a parachute. It works best when open.  -- A. Einstein
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Ophiolite on 22/04/2006 18:47:12
As you can tell from my user name JimBob, this interests me. Thank you for posting it.

Observe; collate; conjecture; analyse; hypothesise; test; validate; theorise. Repeat until complete.
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: elegantlywasted on 24/04/2006 14:13:22
MRI helps spot problems before birth
21/04/2006 3:59:24 PM  

Some infants and their families in Alberta are benefiting from the use of MRIs to catch problems before birth.

"An ultrasound just has limits on the type of detailed picture it can obtain," said Dr. Radha Chari, a professor at the University of Alberta's faculty of medicine. "The MRI seems better for us to define things a little bit better."

Chari uses MRIs to help prepare for births that are high-risk.

In the case of six-month-old Taliesin Schultz, doctors in the rural community of Barrhead first spotted a problem with his lungs when his mother had an ultrasound.

She was sent to Edmonton's Royal Alexandra Hospital for an MRI, which allowed the medical team to take a closer look at the spot on the lungs.

"There was a few times that we were considering the fact that we might not ever be able to see him," recalled Taliesin's father, Rick Shultz.

MRI is particularly useful for monitoring how the lungs of a fetus are developing.

For Taliesin, radiologist Dr. Ravi Bhargava was able to determine what was causing the mass in the baby's chest. Taliesin's lungs repaired themselves and he was born without complications.

But if the cyst is larger or the abnormality is different then a child may need surgery after birth, the doctor said.

Knowing what treatment the baby will need ahead of time allows doctors to prepare resources for the child's family, such as counselling or the services of a specialist.

Parents may also learn the location of delivery and its timing beforehand.

Chari and Bhargava first started using the technology several years ago as part of a study on fetal lung development. MRIs are now used for about one in 100 high-risk pregnancies at the hospital.

The results of the study helped to set new standards for lung development for 16- to 40-week-old fetuses, which were published in the journal Radiology.

http://www.cbc.ca

My Question to you is- Isnt radiology (Xrays) toxic to a developing feuts? Why subjec high risk babies to more risks??

-Meg
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 24/04/2006 17:04:08
quote:
Originally posted by elegantlywasted

MRI helps spot problems before birth
21/04/2006 3:59:24 PM  

Some infants and their families in Alberta are benefiting from the use of MRIs to catch problems before birth.

http://www.cbc.ca

My Question to you is- Isnt radiology (Xrays) toxic to a developing feuts? Why subjec high risk babies to more risks??

-Meg



Hi Meg,
MRIs do not use X-rays, they use radio waves and a strong magnetic field:-

"  The Basic Idea
If you have ever seen an MRI machine, you know that the basic design used in most is a giant cube. The cube in a typical system might be 7 feet tall by 7 feet wide by 10 feet long (2 m by 2 m by 3 m), although new models are rapidly shrinking. There is a horizontal tube running through the magnet from front to back. This tube is known as the bore of the magnet. The patient, lying on his or her back, slides into the bore on a special table. Whether or not the patient goes in head first or feet first, as well as how far in the magnet they will go, is determined by the type of exam to be performed. MRI scanners vary in size and shape, and newer models have some degree of openness around the sides, but the basic design is the same. Once the body part to be scanned is in the exact center or isocenter of the magnetic field, the scan can begin.
In conjunction with radio wave pulses of energy, the MRI scanner can pick out a very small point inside the patient's body and ask it, essentially, "What type of tissue are you?" The point might be a cube that is half a millimeter on each side. The MRI system goes through the patient's body point by point, building up a 2-D or 3-D map of tissue types. It then integrates all of this information together to create 2-D images or 3-D models. "
http://electronics.howstuffworks.com/mri1.htm

 
 
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 29/04/2006 15:54:56
Hominid fossils from Ethiopia link ape-men to more distant human ancestors

Berkeley -- New fossils discovered in the Afar desert of eastern
Ethiopia are a missing link between our ape-man ancestors some 3.5
million years ago and more primitive hominids a million years older,
according to an international team led by the University of
California, Berkeley, and Los Alamos National Laboratory in New
Mexico.


The fossils are from the most primitive species of Australopithecus,
 known as Au. anamensis, and date from about 4.1 million years ago,
 said Tim White, a UC Berkeley professor of integrative biology and
one of the team's leaders. The hominid Australopithecus has often
been called an ape-man because, though short-statured, small-brained
and big-toothed, it walked on two legs unlike the great apes.


More primitive hominids in the genus Ardipithecus date from between
4.4 million and 7 million years ago and were much more ape-like,
though they, too, walked on two legs.


"This new discovery closes the gap between the fully blown
Australopithecines and earlier forms we call Ardipithecus," White
said. "We now know where Australopithecus came from before 4 million
years ago."


The fossil finds and an analysis of the hominid's habitat and
evolutionary position are reported by White and co-authors from
Ethiopia, Japan, France and the United States in the April 13 issue
of Nature.


Since the first Australopithecus skull, the famous Taung child, was
discovered in South Africa 82 years ago by Raymond Dart, fossils of
this hominid have been found all over eastern Africa spanning a 3-
million-year time period. Seven separate species have been named,
including the most primitive, Au. anamensis, which dates from 4.2
million years ago, and Au. africanus, Dart's find. The most
specialized species, Au. boisei, died out about 1.2 million years
ago, long after the genus Homo had spread throughout the Old World.


The most famous of the Australopithecine fossils was "Lucy," a 3.5-
foot adult skeleton discovered in the Afar depression in 1974. Her
analytical team included White. Subsequently named Au. afarensis,
this hominid, which lived between 3.6 and 3 million years ago, was
also discovered in the Middle Awash study area, where the new Au.
anamensis fossils were found.


Ardipithecus, on the other hand, was discovered by White and his
team in 1992, based on fossils from Aramis, a village in the Awash
Valley of Ethiopia's Afar rift. White and his team named the 4. 4
million-year-old fossils Ardipithecus ramidus.


The relationship between Australopithecus and Ardipithecus remained
unclear, however, because of a million-year gap between these two
genera. The new fossil finds, jawbones and teeth from each of two
localities, bridge that gap. With Ardipithecus in older rocks and
Au. afarensis in overlying rocks, the newly announced fossils are
intermediate in time and anatomy.


The teeth tell a story about the organism's diet, White said.
Australopithecus's large cheek teeth - anthropologists refer to the
hominid as a megadont, meaning large-toothed - allowed it to subsist
on a broader diet of tough, fibrous plants. The teeth of
Ardipithecus were smaller, restricting it to a diet of softer, less
abrasive food, White said.


"Australopithecus became a superior omnivore, able to eat tubers and
roots with more fiber and grit, adapting it better to times of
scarcity during periods of extended drought," he said. "They may
have been small brained, but they stuck around a long time, fully
half of our zoological family's 6-million-year existence on the
planet."


White and his Middle Awash team are cautious about claiming that the
new fossils are closely related to the most recent member of the
genus Ardipithecus, Ar. ramidus, since the two are separated by only
300,000 years. While Au. anamensis could have rapidly evolved from
Ar. ramidus, contemporary fossils may yet be found. Nevertheless,
White said, the new fossils show clear descent from the genus
Ardipithecus, two species of which have been identified over the
genus's 2 million years of existence. The fact that fossils of Ar.
ramidus, Au. anamensis and Au. afarensis have been found in
successive sediment layers in the same area of the Middle Awash site
also indicates an evolutionary sequence, said White.


"It is fair to say that some species of Ardipithecus gave rise to
Australopithecus," he said.


The first of the newly reported fossils, an upper jawbone with
teeth, was discovered in November 1994 at Aramis, the site of
earlier fossil finds of Au. anamensis. In 2000, 2003 and again in
both January and December 2005, the team found additional teeth and
jaw fragments at Asa Issie, about 10 kilometers west of Aramis. Many
of the teeth were completely shattered, but by water-sieving the
surface sediments, they were able to collect nearly all the
fragments, which White painstakingly reassembled.


In all, teeth and jawbones of eight individuals were found at Asa
Issie, all from about 4.1 million years ago as dated by
paleomagnetic and argon-argon methods by a team led by geologist
Paul Renne, UC Berkeley adjunct professor of earth and planetary
science and director of the independent Berkeley Geochronology
Center. A partial thigh bone and hand and foot bones were very
similar to the Lucy bones found 60 kilometers away in Hadar and
dating from 3 million to 3.4 million years ago. The large, thick
-enameled teeth were judged by the research team to be closest to
Au. anamensis, and ancestral to Au. afarensis.


Hundreds of mammal fossils also were found, allowing the team to
reconstruct the habitat as closed woodland with lots of colobus
monkeys, kudus, pigs, birds and rodents, as well as a collection of
carnivores, primarily hyenas and big cats.


"The abundance of monkeys, kudus and other mammals, and petrified
wood found both at Aramis and Asa Issie shows that a closed, wooded
habitat type persisted over a long period in this part of the Afar
and was favored by early hominids between 4 and 6 million years
ago," said Giday WoldeGabriel of Los Alamos National Laboratory, a
geologist and co-leader of the Middle Awash project.


The Middle Awash team, consisting of 60 scientists from 17
countries, brings expertise in geology, archaeology, paleontology
and evolutionary biology to the study of fossils unearthed in
Ethiopia spanning nearly 6 million years of evolution - from the
first hominids that split from chimpanzees to modern humans, Homo
sapiens sapiens. The team continues to unearth fossils from what
White describes as "the world's best window on human evolution."


SOURCE:EUREKERALERT.ORG

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 29/04/2006 15:56:55
Apollo lunar rocks suggest meteorite shower
OREGON STATE UNIVERSITY NEWS RELEASE


New age measurements of lunar rocks returned by the Apollo space missions have revealed that a surprising number of the rocks show signs of melting about 3.9 billion years ago, suggesting that the moon - and its nearby neighbor Earth - were bombarded by a series of large meteorites at that time.

The idea that meteorites have hammered the moon's surface isn't news to scientists. The lunar surface is pock-marked with large craters carved out by the impact of crashing asteroids and meteorites, said Robert Duncan, a professor and associate dean in the College of Oceanic and Atmospheric Sciences at Oregon State University.

But the narrow range of the impact dates suggests to researchers that a large spike in meteorite activity took place during a 100-million year interval - possibly the result of collisions in the asteroid belt with comets coming from just beyond our solar system.

Results of the study are being published in Geochimica et Cosmochimica Acta, the journal of the international Meteoritical Society. Co-authors with Duncan are Marc Norman of the Australian National University and John Huard, also an oceanographer at OSU. The study was funded by NASA.

Tiny melted fragments from the lunar rocks were dated at the noble gas geochronology laboratory at Oregon State. Duncan and Huard were able to use radiometric dating techniques to determine when the rocks had melted after being struck by meteorites. What is particularly intriguing, Duncan says, is that this apparent spike in meteorite activity took place about 3.8 to 4 billion years ago - an era that roughly coincides with when scientists believe life first began on Earth, as evidenced by the fossil record of primitive one-cell bacteria.

It is possible that life was introduced to Earth from one of these meteorites, Duncan said. Or it could have developed spontaneously once the bombardment subsided, or developed beneath the ocean near life-nurturing hydrothermal vents. The lack of evidence on Earth makes the analysis of moon rocks much more compelling. The meteorite activity that bombarded the moon likely struck our planet as well.

"Unfortunately, we haven't found many very old rocks on Earth because of our planet's surface is constantly renewed by plate tectonics, coupled with erosion," Duncan said. "By comparison, the moon is dead, has no atmosphere and provides a record of meteorite bombardment that we can only assume is similar to that on Earth."

When the solar system was formed, scientists say, it spun away from the sun like a huge, hot disk that subsequently condensed into planets. At least nine planets survived, sucking in loose space matter from around them. Those planets closer to the sun were more solid, while those farther away were comprised primarily of gases.

Over time, the space debris has lessened, either being gravitationally collected into the planets, or smashed into cosmic dust through collisions with other objects. The discovery of this apparent spike in meteorite activity suggests to the authors that a major event took place.

"We may have had a 10th and 11th planet that collided," Duncan said, "or it's possible that the outward migration of Neptune may have scattered comets and small planet bodies, inducing collisions in the asteroid belt. The close passing of a neighboring star could have had a similar effect."

Duncan and his colleagues examined about 50 different rock samples scooped up by astronauts on the Apollo missions. All but a few of them produced ages close to 3.9 billion years and they exhibited different chemical "fingerprints," indicating that they had melted from different meteorites and lunar surface rocks.

"The evidence is clear that there was repeated bombardment by meteorites," Duncan said.

When meteorites collide with the moon, the surface rock and the meteorites partially melt, and then turn to glass. After the glasses quenched, they slowly began to accumulate argon gas that scientists can measure and calculate from the known isotopic decay rate (from potassium) to determine age.

"The formation of glass from the melting is like starting a clock," Duncan said. "It resets the time for us to determine billions of years later."

Duncan and his colleagues say the intense bombardment ended about 3.85 billion years ago, and there has been a slowly declining pattern of meteorite activity since. Many of the prominent craters found on the moon date back to that era, including Imbrium, at 3.84 billion years; Serenitatis, 3.89 billion years; and Nectaris, 3.92 billion years.

Many of the moon's craters are 10 to 100 kilometers across and scientists say that meteorites of that size or larger may have struck the Earth in the past. Such meteorites impacts may have been responsible for the extinction of dinosaurs 65 million years ago, and a mass extinction that wiped out an estimated 75 percent of the Earth's plant and animal species 250 million years ago.

However, Duncan said, these mass extinctions could also be linked to climate, disease and volcanism - or a combination of such factors.

"It is clear that there was a spike of meteorite activity on the moon about 3.9 billion years ago, and that it lasted for roughly 100 million years," Duncan said. "The moon provides important information about the early history of our solar system that is missing from the Earth's geologic record."

SOURCE: SPACEFLIGHTNOW.COM

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 04/05/2006 15:11:10
Mobile DNA part of evolution's toolbox
The repeated copying of a small segment of DNA in the genome of a primeval fish may have been crucial to the transition of ancient animals from sea to land, or to later key evolutionary changes in land vertebrates. The discovery is "tantalizing evidence" that copied DNA elements known as retroposons could be an important source of evolutionary innovations, says the director of the research, Howard Hughes Medical Institute investigator David Haussler.
"The big question is whether this is a special case or whether it's the tip of the iceberg," says Haussler, who is at the University of California, Santa Cruz. A report on the research is published in the May 4, 2006, issue of the journal Nature.

Haussler and his colleagues were led to the discovery through their work on what they call "ultraconserved elements" -- segments of DNA hundreds of nucleotides long that are almost exactly the same in a wide variety of vertebrate organisms. Haussler and postdoctoral fellow Gill Bejerano discovered the ultraconserved elements in 2003, and since then they have been trying to figure out how they arose and what function they serve.

One ultraconserved element in particular caught their eye. "We were very interested in this sequence, because it had a number of copies elsewhere in the genome," says Bejerano, who is the first author of the study. Close copies of the sequence were ubiquitous in amphibians, birds, and mammals, indicating that it served an important function. "We found it in every species for which we have genomes, from frogs to humans," says Bejerano.

Comparing the sequence to other species also turned up a big surprise. When the researchers compared the human ultraconserved element to all the DNA sequences in the public database GenBank, the closest match was to DNA from the coelacanth -- an ancient fish thought to have gone extinct millions of years ago until a live specimen was caught in 1938 off the east coast of South Africa. The coelacanth is a descendant of the ancient marine organism that gave rise to the terrestrial vertebrates more than 360 million years ago. Humans are therefore separated from the coelacanth by hundreds of millions of years of evolution, yet the two organisms still share critical DNA sequences.

In the coelacanth, the ultraconserved segments were produced by a retroposon known as a short interspersed repetitive element, or SINE, which is a piece of DNA that can make copies of itself and insert those copies elsewhere in an organism's genome. Haussler and his colleagues called this SINE the LF-SINE, where LF stands for lobe-finned fishes--the group of fishes that gave rise to both the coelacanth and terrestrial vertebrates.

The LF-SINE was very active in the evolutionary lineage leading to the terrestrial vertebrates, but much less active after animals moved onto land. Humans have 245 recognizable copies of the LF-SINE, most or all of which probably were in place before the origins of the mammals. But in the lineage leading to the coelacanth, the LF-SINE remained active, so that the coelacanth genome is now estimated to contain hundreds of thousands of copies of the sequence.

The close copies of the ultraconserved element scattered around vertebrate genomes have changed less than would be expected over evolutionary time, indicating that they are functionally important. But relatively few of the copies contain parts that code for proteins, which suggests they instead are helping to regulate when genes are turned on and off. Furthermore, when Bejerano analyzed the locations of the copies, he found that they tended to be near genes that control the development of the brain.

Haussler and his colleagues then looked at a particular example -- a copy of the ultraconserved element that is near a gene called Islet 1 (ISL1). ISL1 produces a protein that helps control the growth and differentiation of motor neurons. In the laboratory of Edward Rubin at the University of California, Berkeley, postdoctoral fellow Nadav Ahituv combined the human version of the LF-SINE sequence with a "reporter" gene that would produce an easily recognizable protein if the LF-SINE were serving as its on-off switch. He then injected the resulting DNA into the nuclei of fertilized mouse eggs. Eleven days later, he examined the mouse embryos to see whether and where the reporter gene was switched on. Sure enough, the gene was active in the embryos' developing nervous systems, as would be expected if the LF-SINE copy were regulating the activity of ISL1.

The discoverer of mobile DNA elements, Barbara McClintock, suggested in 1950 that they might play a role in the regulation of genes -- a hypothesis that was more fully developed by Roy Britten and Eric Davidson in about 1970, when it was discovered that more than half of the human genome consists of remnants of mobile elements. But the mechanisms underlying this process remained obscure. Haussler's work provides direct evidence that even when they land at some distance from a gene, mobile elements like SINEs can be adapted to serve as regulatory elements that have powerful effects in their new locations. "When you activate a gene in a new context," Bejerano points out, "you get processes that did not occur before."

Bejerano and Haussler's results support the hypothesis that the movement of retroposons can generate evolutionary experiments by adding new regulatory modules to genes. Most of these experiments will have no effects or will harm an organism. But every once in a while, the movement of a regulatory element will give an organism an evolutionary advantage. "And to the extent that [such changes] improve the fitness of an organism," says Haussler, "they eventually will become fixed in a population."

"This suggests a lot of exciting evolutionary avenues," says Haussler, "but we don't yet know how prevalent this kind of evolution is." Other labs have found similar examples of mobile elements that have changed the regulation of genes, and Haussler expects the number of reports to grow. "It's a very exciting time to be looking at the human genome, because there's an enormous amount of DNA that we know is important, but we don't yet know what it's doing."

SOURCE: EUREKALERT


Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 04/05/2006 15:13:07
World-leading microscope shows more detail than ever


A unique 3-dimensional microscope that works in a new way is giving unprecedented insight into microscopic internal structure and chemical composition. It is revealing how materials are affected, over time, by changes in temperature, humidity, weight load and other conditions.
The device could lead to advances in a range of areas, such as healthcare (in furthering, for instance, the understanding of conditions such as osteoporosis), the development of better construction materials, improved oil extraction methods and even the study of fossils.

Like a number of other microscopes, the new microscope harnesses X-rays to provide information about an object's internal structure down to micron scale. (A micron is a millionth of a metre.) What makes it unique, however, is its innovative use of a technique called 'time delay integration', which enables it to generate much better images of larger objects than any other device. This means that microscopic structure can be studied with greater accuracy.

With EPSRC funding, a multi-disciplinary team drawn from six UK universities has been developing and utilising the microscope, which, although similar to the CT scanners used in healthcare, can view things in much greater detail.

X-ray microscopes can produce 3-d internal pictures of an object by taking a large number of 2-d images from different angles – this is known as X-ray microtomography. However, the new microscope's combining of this technique with time delay integration is completely unique. Through averaging out imperfections in the image across all pixels, this approach enables the microscope to produce clearer and bigger pictures than previously possible (see 'Notes for Editors').

Some of the microscope's many potential uses include:

Studying how bone and tooth tissue behave in conditions such as osteoporosis, osteoarthritis and tooth decay. By improving understanding of these conditions, the microscope could aid prevention, earlier diagnosis and more effective treatment.
Observing how crude oil is held in sandstone pores. This knowledge could assist the development of more efficient ways of exploiting both offshore and onshore oil resources.
Investigating the mechanical behaviour of metals at a microscopic level. This could contribute to development of more reliable, more resilient and lower weight materials for use in construction, aviation and the storage & transportation of dangerous substances.
Detailed study of fossils embedded in rocks without having to remove and risk damaging them.
Professor Jim Elliott of Queen Mary, University of London led the project. "As well as developing these microscopes to study subtle variations in internal structure, a main aim of ours is to work with the wider scientific community to identify problems where they could make a real contribution," he says. "There's no limit to what it would be useful or interesting to look at."

The microscope looks set to be a valuable research tool that many different organisations in a wide range of sectors could benefit from using. The team is currently planning to seek funding to support the development of a radical new design that could be even more effective.

SOURCE: EUREKALERT


Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 06/05/2006 15:53:02
Man may have caused pre-historic extinctions

New research shows that pre-historic horses in Alaska may have been hunted into extinction by man, rather than by climate change as previously thought.

The discovery by Andrew Solow of Woods Hole Oceanographic Institute, US, David Roberts of the Royal Botanic Garden, Kew and Karen Robbirt of the University of East Anglia (UEA) is published this week in Proceedings of the National Academy of Sciences (PNAS).

The accepted view had previously been that the wild horses became extinct long before the extinction of mammoths and the arrival of humans from Asia - ruling out the possibility that they were over-hunted by man. One theory had been that a period of climate cooling wiped them out.

However, the researchers have discovered that uncertainties in dating fossil remains and the incompleteness of fossil records mean that the survival of the horse beyond the arrival of humans cannot be ruled out.

The PNAS paper develops a new statistical method to help resolve the inherent problems associated with dating fossils from the Pleistocene period. The aim is to provide a far more accurate timetable for the extinction of caballoid horses and mammoths and, ultimately, the cause.

"This research is exciting because it throws open the debate as to whether climate change or over-hunting may have led to the extinction of pre-historic horses in North America," said UEA's Karen Robbirt.

The Pleistocene period refers to the first epoch of the Quarternary period between 1.64 million and 10,000 years ago. It was characterised by extensive glaciation of the northern hemisphere and the evolution of modern man around 100,000 years ago.

It is known that the end of the Pleistocene period was a time of large-scale extinctions of animals and plants in North America and elsewhere but the factors responsible have remained open to question, with climate change and over-hunting by humans the prime suspects. Ends

SOURCE: EUREKALERT.

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: JimBob on 09/05/2006 00:34:16
Last Update: Tuesday, May 9, 2006. 9:00am (AEST)
New neighbours: Two dwarf galaxies have been found near the Milky Way. [File photo]

New neighbours: Two dwarf galaxies have been found near the Milky Way. [File photo] (Reuters)
   
Astronomers spy two dwarf galaxies

Two dim dwarf galaxies are the Milky Way's newest known galactic companions, astronomers studying a vast swath of the sky say.

This brings the total number of dwarf galaxies in the Milky Way's cosmic neighbourhood to 14, but theorists believe there could conceivably be hundreds more.

Scientists studying the Sloan Digital Sky Survey say the two newly-detected dwarfs have been found in the direction of the constellations Canes Venatici (the hunting dogs) and Bootes (the herdsman).

The little galaxy found in Canes Venatici is about 640,000 light years from the sun, a stone's throw in cosmic terms.

A light year is about 10 trillion kilometres, the distance light travels in a year.

The dwarf found in Bootes is about the same distance from the sun.

Even though they are close, the galaxies are hard to spot because they are so dim, a defining characteristic of dwarf galaxies.

The new galaxy in Bootes is the faintest discovered, with a total luminosity of 100,000 suns.
Cold dark matter

Some astronomers theorise that there should be hundreds of clumps of so-called cold dark matter - slow-moving subatomic particles left over from the earliest period of the universe - orbiting the Milky Way, which contains earth.

Each of these clumps should be massive enough to host a dwarf galaxy, but so far only 14 have been found.

The two newest discoveries are among 12 spheroidal dwarf galaxies, two more are the Large Magellanic Cloud and the Small Magellanic Cloud, a pair of irregular dwarfs.

A galaxy is considered a dwarf if it is less than 10 per cent as luminous as the Milky Way, since luminosity is mostly a matter of the total number of stars.

The Sloan Digital Sky Survey, which is managed by a global consortium of museums, universities and other astronomical institutions, aims to ultimately provide detailed images of more than one-quarter of the sky for use by the scientists.

- Reuters

URL = http://www.abc.net.au/news/newsitems/200605/s1633825.htm



The mind is like a parachute. It works best when open.  -- A. Einstein
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 12/05/2006 16:04:56
Dragonfly migration resembles that of birds, scientists say.

Princeton, N.J. - Scientists have discovered that migrating dragonflies and songbirds exhibit many of the same behaviors, suggesting the rules that govern such long-distance travel may be simpler and more ancient than was once thought.

The research, published in the May 11 Biology Letters, is based on data generated by tracking 14 green darner dragonflies with radio transmitters weighing only 300 milligrams -- about a third as much as a paper clip. Green darners are among the 25 to 50 species of dragonflies thought to be migratory among about 5200 species worldwide.

The team of researchers that made the discovery, led by Princeton University's Martin Wikelski, tracked the insects for up to 10 days from both aircraft and handheld devices on the ground. They found that the dragonflies' flight patterns showed many similarities to those of birds that migrate over the same regions of coastal New Jersey.

"The dragonflies' routes have showed distinct stopover and migration days, just as the birds' did," said Wikelski, an associate professor of ecology and evolutionary biology. "Additionally, groups of both birds and dragonflies did not migrate on very windy days and only moved after two successive nights of falling temperatures. We saw other similarities as well, which makes us wonder just how far back in Earth's history the rules for migration were established in its animals."

According to fossil records, dragonflies appeared about 285 million years ago, predating the first birds by about 140 million years.

Wikelski said that the findings could also be an important demonstration of how to track small animals over great distances, a technique that could be useful in agriculture and ecological management.

"These small transmitters could enable us to track animals from space all around the globe if satellites were available," Wikelski said. "Though nearly everyone has heard of animal migration, we actually know very little about how animals move. It could tell us a lot about the way species respond to climate change and other disturbances. Because the economies of many nations are still largely agrarian, a better understanding of how, say, locust swarms travel could assist us with managing both local agriculture and the world economy that hinges upon it."

SOURCE: EUREKALERT.ORG

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 12/05/2006 23:03:19
We will be able to live to 1,000'
By Dr Aubrey de Grey
University of Cambridge

Life expectancy is increasing in the developed world. But Cambridge University geneticist Aubrey de Grey believes it will soon extend dramatically to 1,000. Here, he explains why.

Ageing is a physical phenomenon happening to our bodies, so at some point in the future, as medicine becomes more and more powerful, we will inevitably be able to address ageing just as effectively as we address many diseases today.

I claim that we are close to that point because of the SENS (Strategies for Engineered Negligible Senescence) project to prevent and cure ageing.

It is not just an idea: it's a very detailed plan to repair all the types of molecular and cellular damage that happen to us over time.

And each method to do this is either already working in a preliminary form (in clinical trials) or is based on technologies that already exist and just need to be combined.

This means that all parts of the project should be fully working in mice within just 10 years and we might take only another 10 years to get them all working in humans.

When we get these therapies, we will no longer all get frail and decrepit and dependent as we get older, and eventually succumb to the innumerable ghastly progressive diseases of old age.

We will still die, of course - from crossing the road carelessly, being bitten by snakes, catching a new flu variant etcetera - but not in the drawn-out way in which most of us die at present.

 So, will this happen in time for some people alive today? Probably. Since these therapies repair accumulated damage, they are applicable to people in middle age or older who have a fair amount of that damage.

I think the first person to live to 1,000 might be 60 already.

It is very complicated, because ageing is. There are seven major types of molecular and cellular damage that eventually become bad for us - including cells being lost without replacement and mutations in our chromosomes.

Each of these things is potentially fixable by technology that either already exists or is in active development.

'Youthful not frail'

The length of life will be much more variable than now, when most people die at a narrow range of ages (65 to 90 or so), because people won't be getting frailer as time passes.

The average age will be in the region of a few thousand years. These numbers are guesses, of course, but they're guided by the rate at which the young die these days.

If you are a reasonably risk-aware teenager today in an affluent, non-violent neighbourhood, you have a risk of dying in the next year of well under one in 1,000, which means that if you stayed that way forever you would have a 50/50 chance of living to over 1,000.

And remember, none of that time would be lived in frailty and debility and dependence - you would be youthful, both physically and mentally, right up to the day you mis-time the speed of that oncoming lorry.

Should we cure ageing?

Curing ageing will change society in innumerable ways. Some people are so scared of this that they think we should accept ageing as it is.

I think that is diabolical - it says we should deny people the right to life.

The right to choose to live or to die is the most fundamental right there is; conversely, the duty to give others that opportunity to the best of our ability is the most fundamental duty there is.

There is no difference between saving lives and extending lives, because in both cases we are giving people the chance of more life. To say that we shouldn't cure ageing is ageism, saying that old people are unworthy of medical care.

Playing God?

People also say we will get terribly bored but I say we will have the resources to improve everyone's ability to get the most out of life.

People with a good education and the time to use it never get bored today and can't imagine ever running out of new things they'd like to do.

And finally some people are worried that it would mean playing God and going against nature. But it's unnatural for us to accept the world as we find it.

Ever since we invented fire and the wheel, we've been demonstrating both our ability and our inherent desire to fix things that we don't like about ourselves and our environment.

We would be going against that most fundamental aspect of what it is to be human if we decided that something so horrible as everyone getting frail and decrepit and dependent was something we should live with forever.

If changing our world is playing God, it is just one more way in which God made us in His image.

SOURCE: story from BBC NEWS:
http://news.bbc.co.uk/go/pr/fr/-/1/hi/uk/4003063.stm

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 15/05/2006 18:11:28
Light's most exotic trick yet: So fast it goes ... backwards?
UNIVERSITY OF ROCHESTER NEWS RELEASE
Posted: May 14, 2006

In the past few years, scientists have found ways to make light go both faster and slower than its usual speed limit, but now researchers at the University of Rochester published a paper on May 12 in Science on how they've gone one step further: pushing light into reverse. As if to defy common sense, the backward-moving pulse of light travels faster than light.

Confused? You're not alone.

"I've had some of the world's experts scratching their heads over this one," says Robert Boyd, the M. Parker Givens Professor of Optics at the University of Rochester. "Theory predicted that we could send light backwards, but nobody knew if the theory would hold up or even if it could be observed in laboratory conditions."

Boyd recently showed how he can slow down a pulse of light to slower than an airplane, or speed it up faster than its breakneck pace, using exotic techniques and materials. But he's now taken what was once just a mathematical oddity-negative speed-and shown it working in the real world.

"It's weird stuff," says Boyd. "We sent a pulse through an optical fiber, and before its peak even entered the fiber, it was exiting the other end. Through experiments we were able to see that the pulse inside the fiber was actually moving backward, linking the input and output pulses."

So, wouldn't Einstein shake a finger at all these strange goings-on? After all, this seems to violate Einstein's sacred tenet that nothing can travel faster than the speed of light.

"Einstein said information can't travel faster than light, and in this case, as with all fast-light experiments, no information is truly moving faster than light," says Boyd. "The pulse of light is shaped like a hump with a peak and long leading and trailing edges. The leading edge carries with it all the information about the pulse and enters the fiber first. By the time the peak enters the fiber, the leading edge is already well ahead, exiting. From the information in that leading edge, the fiber essentially 'reconstructs' the pulse at the far end, sending one version out the fiber, and another backward toward the beginning of the fiber."

Boyd is already working on ways to see what will happen if he can design a pulse without a leading edge. Einstein says the entire faster-than-light and reverse-light phenomena will disappear. Boyd is eager to put Einstein to the test.

So how does light go backwards?

Boyd, along with Rochester graduate students George M. Gehring and Aaron Schweinsberg, and undergraduates Christopher Barsi of Manhattan College and Natalie Kostinski of the University of Michigan, sent a burst of laser light through an optical fiber that had been laced with the element erbium. As the pulse exited the laser, it was split into two. One pulse went into the erbium fiber and the second traveled along undisturbed as a reference. The peak of the pulse emerged from the other end of the fiber before the peak entered the front of the fiber, and well ahead of the peak of the reference pulse.

But to find out if the pulse was truly traveling backward within the fiber, Boyd and his students had to cut back the fiber every few inches and re-measure the pulse peaks when they exited each pared-back section of the fiber. By arranging that data and playing it back in a time sequence, Boyd was able to depict, for the first time, that the pulse of light was moving backward within the fiber.

To understand how light's speed can be manipulated, think of a funhouse mirror that makes you look fatter. As you first walk by the mirror, you look normal, but as you pass the curved portion in the center, your reflection stretches, with the far edge seeming to leap ahead of you (the reference walker) for a moment. In the same way, a pulse of light fired through special materials moves at normal speed until it hits the substance, where it is stretched out to reach and exit the material's other side.

Conversely, if the funhouse mirror were the kind that made you look skinny, your reflection would appear to suddenly squish together, with the leading edge of your reflection slowing as you passed the curved section. Similarly, a light pulse can be made to contract and slow inside a material, exiting the other side much later than it naturally would.

To visualize Boyd's reverse-traveling light pulse, replace the mirror with a big-screen TV and video camera. As you may have noticed when passing such a display in an electronics store window, as you walk past the camera, your on-screen image appears on the far side of the TV. It walks toward you, passes you in the middle, and continues moving in the opposite direction until it exits the other side of the screen.

A negative-speed pulse of light acts much the same way. As the pulse enters the material, a second pulse appears on the far end of the fiber and flows backward. The reversed pulse not only propagates backward, but it releases a forward pulse out the far end of the fiber. In this way, the pulse that enters the front of the fiber appears out the end almost instantly, apparently traveling faster than the regular speed of light. To use the TV analogy again-it's as if you walked by the shop window, saw your image stepping toward you from the opposite edge of the TV screen, and that TV image of you created a clone at that far edge, walking in the same direction as you, several paces ahead.

"I know this all sounds weird, but this is the way the world works," says Boyd.

SOURCE:SPACEFLIGHTNOW.COM

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 15/05/2006 18:13:30
New scenario explains origin of Neptune's oddball moon
UNIVERSITY OF CALIFORNIA-SANTA CRUZ NEWS RELEASE
Posted: May 14, 2006

Neptune's large moon Triton may have abandoned an earlier partner to arrive in its unusual orbit around Neptune. Triton is unique among all the large moons in the solar system because it orbits Neptune in a direction opposite to the planet's rotation (a "retrograde" orbit). It is unlikely to have formed in this configuration and was probably captured from elsewhere.

In the May 11 issue of the journal Nature, planetary scientists Craig Agnor of the University of California, Santa Cruz, and Douglas Hamilton of the University of Maryland describe a new model for the capture of planetary satellites involving a three-body gravitational encounter between a binary and a planet. According to this scenario, Triton was originally a member of a binary pair of objects orbiting the Sun. Gravitational interactions during a close approach to Neptune then pulled Triton away from its binary companion to become a satellite of Neptune.

"We've found a likely solution to the long-standing problem of how Triton arrived in its peculiar orbit. In addition, this mechanism introduces a new pathway for the capture of satellites by planets that may be relevant to other objects in the solar system," said Agnor, a researcher in UCSC's Center for the Origin, Dynamics, and Evolution of Planets.

With properties similar to the planet Pluto and about 40 percent more massive, Triton has an inclined, circular orbit that lies between a group of small inner moons with prograde orbits and an outer group of small satellites with both prograde and retrograde orbits. There are other retrograde moons in the solar system, including the small outer moons of Jupiter and Saturn, but all are tiny compared to Triton (less than a few thousandths of its mass) and have much larger and more eccentric orbits about their parent planets.

Triton may have come from a binary very similar to Pluto and its moon Charon, Agnor said. Charon is relatively massive, about one-eighth the mass of Pluto, he explained.

"It's not so much that Charon orbits Pluto, but rather both move around their mutual center of mass, which lies between the two objects," Agnor said.

In a close encounter with a giant planet like Neptune, such a system can be pulled apart by the planet's gravitational forces. The orbital motion of the binary usually causes one member to move more slowly than the other. Disruption of the binary leaves each object with residual motions that can result in a permanent change of orbital companions. This mechanism, known as an exchange reaction, could have delivered Triton to any of a variety of different orbits around Neptune, Agnor said.

An earlier scenario proposed for Triton is that it may have collided with another satellite near Neptune. But this mechanism requires the object involved in the collision to be large enough to slow Triton down, but small enough not to destroy it. The probability of such a collision is extremely small, Agnor said.

Another suggestion was that aerodynamic drag from a disk of gas around Neptune slowed Triton down enough for it to be captured. But this scenario puts constraints on the timing of the capture event, which would have to occur early in Neptune's history when the planet was surrounded by a gas disk, but late enough that the gas would disperse before it slowed Triton's orbit enough to send the moon crashing into the planet.

In the past decade, many binaries have been discovered in the Kuiper belt and elsewhere in the solar system. Recent surveys indicate that about 11 percent of Kuiper belt objects are binaries, as are about 16 percent of near-Earth asteroids.

"These discoveries pointed the way to our new explanation of Triton's capture," Hamilton said. "Binaries appear to be a ubiquitous feature of small-body populations."

The Pluto/Charon pair and binaries in the Kuiper belt are especially relevant for Triton, as their orbits abut Neptune's, he said.

"Similar objects have probably been around for billions of years, and their prevalence indicates that the binary-planet encounter that we propose for Triton's capture is not particularly restrictive," Hamilton said.

The exchange reaction described by Agnor and Hamilton may have broad applications in understanding the evolution of the solar system, which contains many irregular satellites. The researchers plan to explore the implications of their findings for other satellite systems.

This research was supported by grants from NASA's Planetary Geology and Geophysics, Outer Planet Research, and Origins of Solar Systems programs.


SOURCE: SPACEFLIGHTNOW.COM

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 18/05/2006 14:00:39


17 May 2006
" Q. Did humans and chimps once interbreed?

Tangled family tree
 By Bob Holmes

It goes to the heart of who we are and where we came from. Our human ancestors were still interbreeding with their chimp cousins long after first splitting from the chimpanzee lineage, a genetic study suggests. Early humans and chimps may even have hybridised completely before diverging a second time. If so, some of the earliest fossils of proto-humans might represent an abortive first attempt to diverge from chimps, rather than being our direct ancestors. "
http://www.newscientist.com/article.ns?id=mg19025525.000&feedId=online-news_rss20

A. YES, look at Wayne Rooney and President George W. Bush [:)].

Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 19/05/2006 15:29:10
Apes shown to be able to plan ahead
Associated Press

WASHINGTON — They don't bring along an umbrella or sunglasses that might be needed later, but researchers say apes, like people, can plan ahead.

Both orangutans and bonobos were able to figure out which tool would work in an effort to retrieve grapes, and were able to remember to bring that tool along hours later, researchers report in Friday's issue of the journal Science.

In a series of laboratory tests the apes were shown the tools and grapes, allowed to retrieve grapes, and then removed from the area where the treats were available.

They were allowed back from one to 14 hours later and most were able to bring along the correct tool to get the treats, report Nicholas J. Mulcahy and Josep Call of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.

The researchers said the finding suggests that planning ahead arose at least 14 million years ago, when the last common ancestor of bonobos, orangutans and humans lived.

While the findings do not necessarily imply that the apes are able to anticipate a future state of mind, they are nonetheless groundbreaking, Thomas Suddendorf of the University of Queensland in Australia said in a commentary.

"By identifying what capacities our closest living relatives share with us, we can get a glimpse at our evolutionary past," Suddendorf said.

In a separate paper in ScienceExpress, the electronic version of Science, researchers report that scrub jays look over their shoulders when hiding food for future use and, if they think another bird saw where they put it, will relocate their cache.

The report by Nicola S. Clayton and colleagues at the University of Cambridge in England noted that relocating food was common when a bird thought it had been observed by a more dominant bird, but not when a partner was present.

The findings indicate that the birds act to avoid the possibility that a non-partner will raid their stored food, and remember who was around when they hid it, the researchers say.

SOURCE: CTV.CA


Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 24/05/2006 15:37:00
Polar bear + Grizzly bear = Pizzly Bear

" DNA Tests Confirm Bear Was a Hybrid

Roger Kuptana, an Inuvialuit guide from Sachs Harbour, Northwest Territories, was the first to suspect it had actually happened when he proposed that a strange-looking bear shot last month by an American sports hunter might be half polar bear, half grizzly.

Territorial officials seized the creature after noticing its white fur was scattered with brown patches and that it had the long claws and humped back of a grizzly. Now a DNA test has confirmed that it is indeed a hybrid - possibly the first documented in the wild.

"We've known it's possible, but actually most of us never thought it would happen," said Ian Stirling, a polar bear biologist with the Canadian Wildlife Service in Edmonton. "
http://enews.earthlink.net/article/top?guid=20060511/4462b6c0_3ca6_15526200605112014489028

Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 02/06/2006 22:56:00
Tamed 11,400 years ago, figs were likely first domesticated crop

Long before the grains, fig domestication may have marked a decisive shift in human history


CAMBRIDGE, Mass. -- Archaeobotanists have found evidence that the dawn of agriculture may have come with the domestication of fig trees in the Near East some 11,400 years ago, roughly a thousand years before such staples as wheat, barley, and legumes were domesticated in the region. The discovery dates domesticated figs to a period some 5,000 years earlier than previously thought, making the fruit trees the oldest known domesticated crop.

Ofer Bar-Yosef of Harvard University and Mordechai E. Kislev and Anat Hartmann of Bar-Ilan University report their findings in this week's issue of the journal Science.

"Eleven thousand years ago, there was a critical switch in the human mind -- from exploiting the earth as it is to actively changing the environment to suit our needs," says Bar-Yosef, professor of anthropology in Harvard's Faculty of Arts and Sciences and curator of Paleolithic archaeology at Harvard's Peabody Museum of Archaeology and Ethnology. "People decided to intervene in nature and supply their own food rather than relying on what was provided by the gods. This shift to a sedentary lifestyle grounded in the growing of wild crops such as barley and wheat marked a dramatic change from 2.5 million years of human history as mobile hunter-gatherers."

The researchers found nine small figs and 313 fig drupelets (a small part of an aggregate fruit such as a fig) at Gilgal I, a village in the Lower Jordan Valley, just 8 miles north of ancient Jericho, known to have been inhabited for some 200 years before being abandoned roughly 11,200 years ago. The carbonized figs were not distorted, suggesting that they may have been dried for human consumption. Similar fig drupelets were found at a second site located some 1.5 kilometers west of Gilgal.

The scientists compared the ancient figs to modern wild and domesticated variants and determined that they were a mutant selectively propagated by humans. In this variety of fig, known as parthenocarpic, the fruit develops without insect pollination and is prevented from falling off the tree, allowing it to become soft, sweet, and edible. However, because such figs do not produce seeds, they are a reproductive dead end unless humans interfere by planting shoots from the parthenocarpic trees.

"Once the parthenocarpic mutation occurred, humans must have recognized that the resulting fruits do not produce new trees, and fig tree cultivation became a common practice," Bar-Yosef says. "In this intentional act of planting a specific variant of fig tree, we can see the beginnings of agriculture. This edible fig would not have survived if not for human intervention."

Figs are very easily propagated: A piece of stem stuck in the ground will sprout roots and grow into a plant. No grafting or seeds are necessary. Bar-Yosef, Kislev, and Hartmann suggest that this ease of planting, along with improved taste resulting from minor mutations, may explain why figs were domesticated some five millennia before other fruit trees, such as the grape, olive, and date.

"The reported Gilgal figs, stored together with other vegetal staples such as wild barley, wild oat, and acorns, indicate that the subsistence strategy of these early Neolithic farmers was a mixed exploitation of wild plants and initial fig domestication," Bar-Yosef says. "Apparently, this kind of economy, a mixture of cultivation of wild plants, planting fig trees and gathering other plant foods in nature, was widely practiced during the second half of the 12th millennium before present throughout the Levant, the western wing of the Fertile Crescent."

###


Bar-Yosef, Kislev, and Hartmann's research was sponsored by the American School of Prehistoric Research at Harvard's Peabody Museum, the Israel Museum in Jerusalem, the Shelby-White-Leon Levi Foundation, and the Koschitzky Foundation at Bar-Ilan University.

SOURCE; EUREKA ALERT

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 05/06/2006 17:23:52
" Source: Max Planck Institute of Biochemistry

Posted: June 2, 2006

Semiconductor Brain: Nerve Tissue Interfaced With A Computer Chip

For the first time, scientists at the Max-Planck Institute for Biochemistry in Martinsried near Munich coupled living brain tissue to a chip equivalent to the chips that run computers. The researchers under Peter Fromherz have reported this news in the online edition of the Journal of Neurophysiology (May 10, 2006).

Before informational input perceived by the mammalian brain is stored in the long-term memory, it is temporarily memorised in the hippocampus*. Understanding the function of the hippocampus as an important player in the memory process is a major topic of current brain research. Thin slices of this brain region provide the appropriate material to study the intact neural network of the hippocampus.

Methods commonly used in neurophysiology are invasive, restricted to a small number of cells or suffer from low spatial resolution. The scientists in Martinsried developed a revolutionary non- invasive technique that enables them to record neural communication between thousands of nerve cells in the tissue of a brain slice with high spatial resolution. This technique involves culturing razor-thin slices of the hippocampus region on semiconductor chips. These chips were developed in collaboration with Infineon Technologies AG and excel in their density of sensory transistors: 16384 transistors on an area of one square millimeter record the neural activity in the brain.

Recording the activity patterns of the united cell structure of an intact mammalian brain tissue represents a significant technological breakthrough. Employing the new technique, the biophysicists working under the direction of Peter Fromherz were able to visualize the influence of pharmaceutical compounds on the neural network. This makes the “brain-chip” from Martinsried a novel test system for brain and drug research.

As early as 1991, Peter Fromherz and his co-workers succeeded in interfacing single leech nerve cells with semiconductor chips. Subsequent research gave rise to bidirectional communication between chip and small networks of a few molluscan nerve cells. In this project, it was possible to detect the signalling between cells via their synapses. The chips used in these studies were developed and produced by the scientists themselves. The production requirements of the chip described above made collaboration with industry indispensable. With the resulting novel hybrid system of neural tissue and semiconductor, the scientists take a great step forward towards neurochip prosthetics and neurocomputation.

Original publication: M. Hutzler, A. Lambacher, B. Eversmann, M. Jenkner, R. Thewes, and P. Fromherz: High- resolution multi-transistor array recording of electrical field potentials in cultured brain slices. Journal of Neuropyhsiology "

http://www.sciencedaily.com/releases/2006/06/060602172512.htm
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: JimBob on 11/06/2006 03:02:45
Public release date: 9-Jun-2006
[ Print Article | E-mail Article | Close Window ]

Contact: Stuart Wolpert
swolpert@support.ucla.edu
310-206-0511
University of California - Los Angeles


UCLA physicists report advance toward nanotechy approach to protein engineering

UCLA physicists report a significant step toward a new approach to protein engineering in the June 8 online edition, and in the July print issue, of the Journal of the American Chemical Society.

"We are learning to control proteins in a new way," said Giovanni Zocchi, UCLA associate professor of physics and co-author of the study. Zocchi said the new approach could lead ultimately to "smart medicines that can be controlled" and could have reduced side effects. Mimicking one essential cellular control mechanism, Zocchi's laboratory has completed an important preliminary step.

Zocchi and UCLA physics graduate student Brian Choi report one representative example where the chemical mechanism by which the cell controls the function of its proteins can be effectively replaced, in vitro, by mechanical control. Specifically, they show how an enzyme complex called Protein Kinase A (PKA) -- which plays a fundamental role in the cell's signaling and metabolic pathways, and is controlled in the cell by a ubiquitous messenger molecule called cyclic AMP -- can instead be controlled mechanically by a nanodevice that the researchers attached to the enzyme complex. The nanodevice is essentially a molecular spring made of DNA.

"Molecular biologists have been trained for 50 years to think that because the sequence of amino acids determines a protein's structure and the structure determines its function, if you want to change the structure, the way to do so is to change the sequence of amino acids. While that approach is correct, it is not the only way. We are introducing the notion that you can keep the sequence but change the structure with mechanical forces.

"This research has many ramifications, and may lead to a better fundamental understanding, as well as new directions for biotechnology and perhaps new approaches to medical treatments."

PKA, a complex of four protein molecules, contains two regulatory subunits and two catalytic subunits. Zocchi and Choi mechanically activated PKA by placing a controlled mechanical stress on two specific points in the regulatory subunit, which causes that subunit to fall off from the catalytic subunit, activating the enzyme.

In order to obtain the desired effect, the mechanical tension is applied at specific locations in the regulatory subunit, Choi said. Knowing those locations requires a detailed understanding of the structure of the enzyme.

The research was federally funded by the National Science Foundation.

Proteins, the molecular machines that perform all tasks in the living cell, are switched on and off in living cells by a mechanism called allosteric control; proteins are regulated by other molecules that bind to their surface, inducing a change of conformation, or distortion in the shape, of the protein, making the protein either active or inactive, Zocchi explained.

Cyclic AMP (cAMP) binds to PKA's regulatory subunit and induces a change of conformation that leads to the catalytic subunit's detaching from the regulatory subunit; this separation of the two subunits is how the enzyme complex is turned on in the cell, Zocchi said.

"We can activate the enzyme mechanically, while leaving intact the natural activation mechanism by cAMP," said Zocchi, a member of the California NanoSystems Institute. "We believe this approach to protein control can be applied to virtually any protein or protein complex."

Zocchi's group first demonstrated mechanical control of protein conformation last year, when the physicists attached a controllable molecular spring, made of a short piece of DNA, to a protein and used it to inhibit its function. In the new research, the group succeeded in activating the enzyme PKA through the same principle, by using the molecular spring to induce the change in conformation that, in the cell, is induced by the natural activator of PKA (the signaling molecule cAMP).

Zocchi's group can mimic with mechanical tension the natural allosteric mechanism by which PKA is regulated by cAMP. PKA is significantly more complex than the protein that Zocchi's group used last year.

What are Zocchi's future research plans?

"I want to see whether we can make molecules which kill a cell based on the genetic signature of the cell," Zocchi said. "Cancer cells would be an obvious application. This will however require many further steps. So far, we have only worked in vitro. The exciting part is, from the outside, cancer cells can look like normal cells, but inside they carry a genetic mark.

"In the future, perhaps we can control more complicated molecular machines such as ribosomes. Many antibiotics work by blocking the ribosome of bacteria."

SOURCE: http://www.eurekalert.org/pub_releases/2006-06/uoc--upr060806.php

The mind is like a parachute. It works best when open.  -- A. Einstein
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 14/06/2006 15:24:28
Last Updated: Monday, 5 June 2006, 19:29 GMT 20:29 UK

(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi24.photobucket.com%2Falbums%2Fc23%2FSUEDONIM%2FBEATINGHEARTTRANSPLANT.jpg&hash=57d445615dc133b46be0b483603bbcfa)
 

" Beating-heart transplant UK first  
 
Doctors have carried out the UK's first successful beating-heart transplant.
The recipient, a 58-year-old man who received his new heart two weeks ago at Papworth Hospital in Cambridge, is said to be doing "extremely well".

The new technique involves keeping a donated heart warm and beating throughout the procedure, rather than packing it in ice for transport.
One expert told BBC Radio 4's Today programme it could "triple or quadruple" the number of transplants.

The process gives doctors more time to get hearts to the recipient.

Donor hearts are normally given a high dose of potassium to stop them beating and are packed in ice which helps to keep them in a state of "suspended animation".

But there is only a four-to-six-hour window for the organ to be transplanted into the recipient, which could be a problem if a heart becomes available in a remote area - many organs in the UK are transported by road.

If we look at resuscitating hearts that are currently unusable the number of transplants could be tripled or quadrupled

How system works  

Under the new system, doctors hook the heart up to a machine which keeps it beating with warm oxygenated blood flowing through it.

This gives doctors time to examine the heart for any damage and the chance to better match the organ with a recipient.

The heart can be kept outside the body longer and reaches the transplant patient in much better condition.

The transplant was done as part of a European trial. "
http://news.bbc.co.uk/1/hi/health/5041054.stm

 
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 14/06/2006 16:08:04
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi24.photobucket.com%2Falbums%2Fc23%2FSUEDONIM%2FBEATINGHEARTTRANSPLANT.jpg&hash=57d445615dc133b46be0b483603bbcfa)

If you click on the video option on the above link
you will see that Tupperware really does keep stuff fresh [:)].
 
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Karen W. on 16/06/2006 06:33:17
That is awesome! Absolutely amazed. My brother in law has a mechanical heart valve I think it is. If it quits hes in a lot of trouble. I honestly can't remember, if it was heart or valve, but I know he had a choice of a pigs parts but took the mechanical part instead. You can hear it opening and shuting so says my sister, his ex-wife, There divorsed now.
   I have a bad heart and am constantly amazed at what they can do these days. I had open heart surgery in 1960 or 61, I believe I was about 1 year old. Seems like they are constantly improving things in this area. Very cool!
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 21/06/2006 15:29:47
Chocolate as Sunscreen
Janet Raloff

As if you needed another reason to eat chocolate, German researchers have shown that ingesting types rich in cocoa solids and flavonoids—dark chocolate—can fight skin cancer. Their findings are preliminary because they come from a trial of just 24 women who were recruited to add cocoa to their breakfasts every day for about 3 months.


Half the women drank hot cocoa containing a hefty dose of flavonoids, natural plant-based antioxidants that research has suggested prevent heart attacks. The remaining volunteers got cocoa that looked and tasted the same but that had relatively little of the flavonoids. At the beginning and end of the trial, Wilhelm Stahl of Heinrich-Heine University in Düsseldorf and his colleagues conducted a host of tests on each volunteer. One assessment involved irradiating each woman's skin with slightly more ultraviolet (UV) light than had turned her skin red before the trial began.

The skin of the women who had received the flavonoid-rich cocoa did not redden nearly as much as did the skin of recruits who had drunk the flavonoid-poor beverage. Women getting the abundant flavonoids also had skin that was smoother and moister than that of the other women.

Overexposure to UV light can foster the development of skin cancer. A dietary source of skin protection might offer some innate defense for sunny days when an individual doesn't use sunscreen, Stahl's team says.


Why chocolate?

Chocolate, these scientists note, is just the latest in a range of antioxidant-rich foods holding the potential to shield skin from sun damage. For nearly a decade, Stahl's group has conducted studies with cooked tomato products showing that their ingestion, too, can limit UV-induced skin reddening. Pigmented molecules called carotenoids—especially the one known as lycopene—appeared responsible for tomato's skin-protection benefit (see Dietary protection against sunburn (with recipe)).

Many of the carotenoids in tomatoes are powerful antioxidants that can quash free radicals. These are the molecular fragments that can cause biological havoc when they rip electrons from other molecules. Because many flavonoids also function as potent antioxidants, Stahl's team decided to investigate whether substances in chocolate might offer skin protection.

The researchers recruited women between the ages of 18 and 65. Each volunteer received packets of a dry powder to mix each day with 100 milliliters of hot water—roughly a half cup. Half of the women received powder containing 329 milligrams of flavanols, a type of flavonoid, per serving. The rest got powder delivering a mere 27 mg of flavanols per serving. The primary flavanols were epicatechin and catechin.

Mars Inc., the candy company that has been experimenting with dark-chocolate products rich in flavonoids, supplied the cocoa powder and partially funded the experiment. Harold H. Schmitz, the company's chief science officer, claims that the proprietary recipe for the product retains nearly all of the natural-cocoa flavonoids that most chocolate processing cooks and washes out.

In the June Journal of Nutrition, Stahl's team reports that the women drinking the high-flavonoid cocoa had 15 percent less skin reddening from UV light after 6 weeks of cocoa consumption and 25 percent less after 12 weeks of the trial. Both figures are comparisons with the same women's response to UV light before the study started. The women drinking the cocoa with low flavonoids showed no change during the trial.

Most flavonoids absorb UV light, and this probably played a role in the skin effect, the researchers say. However, they add, skin reddening is also an inflammatory response, and other researchers have linked consumption of flavonoids to ratcheting down the body's synthesis of inflammatory agents.

For the women getting larger doses of flavonoids, blood flow in the skin doubled over the course of the trial in tissue 1 millimeter below the surface, and increased by 37.5 percent in tissue 7 to 8 mm deep. Similar improvements in blood flow through big blood vessels have been witnessed after people have eaten dark chocolate (see Cardiovascular Showdown—Chocolate vs. Coffee).

Moreover, after 12 weeks of consuming the flavanol-rich cocoa, the women's skin was 16 percent denser, 11 percent thicker, 13 percent moister, 30 percent less rough, and 42 percent less scaly than it was at the beginning of the experiment. Although the mechanism for most of these benefits remains unclear, the Düsseldorf researchers suspect that improved blood flow was a contributor.

Mars' Schmitz agrees. "People don't think about it, but in reality your skin, just like every other tissue, depends on healthy blood flow. And in our previous work ... we showed that blood flow in the extremities—the finger tip—was improved" in people receiving cocoa flavonoids. So, he argues, "it wasn't a shot in the dark" to hypothesize that cocoa ingestion might improve overall skin condition and health. Yet, he adds, "I was still surprised to see this."

If follow-up studies confirm these skin-health data, he says, "you're talking about being able to make people look better." He adds, "We did not go into this study with the intention to create a skin-health product, but it now looks like maybe we've got one."



Not just any chocolate


Could a person realistically add enough flavonoids to his or her diet to produce the benefits suggested by the study? Flavonoid quantities in the richer cocoa were "similar to those found in 100 grams [a little over 3 ounces] of dark chocolate," Stahl's group reports.

The cocoa drink provided its flavonoids in a serving that delivered only about 50 calories—far below the 400 to 500 calories ordinarily encountered in candy providing a walloping dose of flavanols. Schmitz concludes that people can, in theory, get this efficacious dose without blimping out.

The rub is that the cocoa used in this study and in others by Mars isn't commercially available. If enough people pester the company for the cocoa, Schmitz says, "eventually we might have to offer such a product." In the meantime, he notes, the company offers a candy, CocoaVia, in flavanol-rich portions that deliver fewer than 100 calories per serving.



Targeting free radicals and more

The new skin-protection data are more than a curiosity, says Hasan Mukhtar, director of dermatology research at the University of Wisconsin–Madison. The results suggest, he says, that dietary flavonoids reach the upper layers of skin and "have the ability to counteract the oxygen free radicals generated as a consequence of exposure to UV radiation."

UV exposure leads not only to impaired immunity and accelerated aging in skin, but also to cancer, especially in light-skinned people, Mukhtar points out. Work by his group and others has shown that UV light triggers many reactions in the body that can lead to tissue damage.

In several papers, Mukhtar and his colleagues have found evidence that natural botanical antioxidants—such as those just tested in cocoa—can inhibit harmful, UV-triggered chemical pathways in the body.

In a study at the Case Western Reserve University School of Medicine, Mukhtar's group applied epicatechin-rich green-tea flavonoids to the skin of volunteers before irradiating the area with UV light. The researchers found that compared with the response of unprotected skin, the tea cut by 60 to 80 percent DNA changes known to play a role in immune suppression and skin cancer. The team noted that the treatment also prevented sunburn.

In the March-April Photochemistry and Photobiology, Mukhtar's team reports the results of treating cultured skin cells with pomegranate fruit extract, a substance rich in flavonoids. When irradiated with UV-light in a test tube, human cells in such an experiment usually undergo stress-induced inflammatory changes that can lead to cancer. However, the pomegranate extract dramatically inhibited those pre-carcinogenic changes.

Mukhtar points out that such data show that "not all of these agents affect the same signaling pathways." This suggests, he says, that eating a mix of flavonoid-rich foods may reinforce the UV protection by simultaneously acting on several potentially damaging processes. Some flavonoid treatments may even prove additive in their skin-protecting role, he says.

Chocolate's agents might offer important backup protection to some of the substances his group has been testing, says Mukhtar.

However, diet isn't the only means of getting these protective agents to the tissues that need them, Mukhtar suspects. He says it may make sense to add them to skin-care products.

That said, I'd prefer to get my protection from eating dark chocolate. Indeed, I look for any excuse to label as therapeutic my bittersweet indulgence.



SOURCE: SCIENCE NEWS ONLINE

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 21/06/2006 15:31:08
The Woman Who Thinks like a Cow

The amazing story of Dr Temple Grandin's ability to read the animal mind, which has made her the most famous autistic woman on the planet.


Dr Temple Grandin has a legendary ability to read the animal mind and understand animal behaviour when no one else can. But this is no feat of telepathy; her explanation is simple. She's convinced she experiences the world much as an animal does and that it's all down to her autistic brain.

Since the 1940s, when Temple was born, our understanding of autism has come a long way. For years during the fifties and sixties many psychologists and doctors believed that the condition was an emotional disorder, the product of a disturbed childhood.

Psychologist Bruno Bettelheim became famous for his theory that children with autism exhibited the symptoms of the condition because their mothers had unconsciously rejected them as babies and young children. Children, he argued, could be cured with psychotherapy.

It wasn't until psychologists such as Bernard Rimland started to put forward evidence for a biological cause of autism that the old ideas lost their public appeal.

Today, neurologists like Professor Nancy Minshew are using brain scanning techniques to investigate the brains of people with autism. As yet it is impossible to diagnose autism based on a brain scan of an individual, but the results do indicate that the brain is different in someone with autism and that this is the real cause of the condition.

When Temple was a baby, research into autism was in its infancy and the doctors didn't even have a name for her condition. Many children like her spent their whole lives in an institution. Temple was lucky, but despite intensive tutoring and care it took her many years to learn basic skills. To this day, socialising continues to be a struggle for her.

For her and many others with autism the condition makes it very difficult to understand what other people are thinking and feeling. To Temple the world is an unpredictable and frightening place.

Temple believes she experiences life like a prey animal in the wild. Her emotions are much simpler than most people's and she feels constantly anxious – always alert and looking for danger. It's this struggle with overwhelming anxiety that led her to discover just how much she has in common with animals and, in particular, cows.

During a summer spent on her aunt's ranch, when she was 16, she began to notice that nervous cattle seemed to calm down when they entered a piece of equipment called a squeeze chute.

Designed to hold the cattle still, whilst they received veterinary treatment, the wooden contraption clamped the cows along either side of the body. As the sides squeezed their flanks, Temple noticed several of the cows become visibly relaxed and calm.

Eager to find a way to conquer her own anxiety she asked her aunt to operate the chute on her. The result was a revelation. Temple felt much calmer and the effect lasted for several hours afterwards.

Inspired by her experiences on the ranch, she built her own human squeeze machine at home. She still has one installed in her bedroom.

There is a scientific explanation for what seems like her quirky behaviour. Psychologists have discovered evidence to suggest that the effects of deep pressure on the body are very real and can be beneficial and calming for many people with autism.

Twenty years ago Temple did something no one with autism had ever done before. She wrote an autobiography. It was her account of what it was like to grow up with autism.

Since then she has written several other books. For parents and scientists working in the field of autism her words are a revelation, giving them an invaluable understanding and insight into the autistic mind.

For Temple, though, her greatest achievements are in the field of animal welfare.

The slaughterhouse seems an unlikely place to look for an animal lover like Temple but it's here that she has carved a unique career. Until Temple stormed on to the scene, in the 1970s, animal welfare was an unheard of phrase in the meat industry. The animals were destined for slaughter and no one cared what happened to them along the way.

But Temple has changed all that. Using her unique ability to observe the world through an animal's eye she has fundamentally redesigned the equipment and buildings where they are held and slaughtered. Today her advice is sought from around the world and half the cattle in the US go to their deaths in humane equipment designed by her.

Labelled 'retarded' at three years old, Temple didn't learn to speak until she was five. But at nearly 60 she's an associate professor of animal science, a best-selling author and the most famous autistic woman on the planet.




SOURCE:BBC.CO.UK

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 26/06/2006 15:21:41
" Electronic TMS Device Zaps Migraine
Jun 23, 2006, 00:52, Reviewed by: Dr. Venkat Yelamanchili
 
Results of a study found that the experimental device appears to be effective in eliminating the headache when administered during the onset of the migraine. The device, called TMS, interrupts the aura phase of the migraine, often described as electrical storms in the brain, before they lead to headaches. Auras are neural disturbances that signal the onset of migraine headaches. People who suffer from migraine headaches often describe “seeing” showers of shooting stars, zigzagging lines and flashing lights, and experiencing loss of vision, weakness, tingling or confusion. What typically follows these initial symptoms is intense throbbing head pain, nausea and vomiting.

Yousef Mohammad, a neurologist at OSU Medical Center who presented the results, says that the patients in this study reported a significant reduction in nausea, noise and light sensitivity post treatment.

"Work functioning also improved, and there were no side effects reported,” Mohammad said.

This magnetic pulse, when held against a person's head, creates an electric current in the neurons of the brain, interrupting the aura before it results in a throbbing headache.

“The device's pulses are painless. “In our study sample, 69 percent of the TMS-related headaches reported to have either no or mild pain at the two-hour post-treatment point compared to 48 percent of the placebo group. In addition, 42 percent of the TMS-treated patients graded their headache response, without symptoms, as very good or excellent compared to 26 percent for the placebo group. These are very encouraging results.”

It was previously believed that migraine headaches start with vascular constriction, which results in an aura, followed by vascular dilation that will lead to a throbbing headache. This new understanding of the migraine mechanism has assisted with the development of the TMS device. "

http://www.rxpgnews.com/research/neurosciences/headache/article_4536.shtml

Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 03/07/2006 15:30:02
" Huge Asteroid to Fly Past Earth July 3
Joe Rao
SPACE.com Skywatching Columnist

An asteroid possibly as large as a half-mile or more in diameter is rapidly approaching the Earth.  There is no need for concern, for no collision is in the offing, but the space rock will make an exceptionally close approach to our planet early on Monday, July 3, passing just beyond the Moon's average distance from Earth.  

Astronomers will attempt to get a more accurate assessment of the asteroid's size by “pinging” it with radar.  

And skywatchers with good telescopes and some experience just might be able to get a glimpse of this cosmic rock as it streaks rapidly past our planet in the wee hours Monday. The closest approach occurs late Sunday for U.S. West Coast skywatchers.

The asteroid, designated 2004 XP14, was discovered on Dec. 10, 2004 by the Lincoln Laboratory Near Earth Asteroid Research (LINEAR), a continuing camera survey to keep watch for asteroids that may pass uncomfortably close to Earth.  

Although initially there were concerns that this asteroid might possibly impact Earth later this century and thus merit special monitoring, further analysis of its orbit has since ruled out any such collision, at least in the foreseeable future.  

Asteroid 2004 XP14 is a member of a class of asteroids known as Apollo, which have Earth-crossing orbits. The name comes from 1862 Apollo, the first asteroid of this group to be discovered. There are now 1,989 known Apollos.

The size of 2004 XP 14 is not precisely known. But based on its brightness, the diameter is believed to be somewhere in the range of 1,345 to 3,018-feet  (410 to 920 meters). That's between a quarter mile and just over a half-mile wide.

Due to the proximity of its orbit to Earth and its estimated size, this object has been classified as a “Potentially Hazardous Asteroid” (PNA) by the Minor Planet Center in Cambridge, Massachusetts. There are currently 783 PNAs.

The latest calculations show that 2004 XP14 will pass closest to Earth at 04:25 UT on July 3 (12:25 a.m. EDT or 9:25 p.m. PDT on July 2).  The asteroid's distance from Earth at that moment will be 268,624-miles (432,308 km), or just 1.1 times the Moon's average distance from Earth. Spotting 2004 XP14 will be a challenge, best accomplished by seasoned observers with moderate-sized telescopes. "

http://news.yahoo.com/s/space/20060626/sc_space/hugeasteroidtoflypastearthjuly3
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 03/07/2006 17:53:22
" Device records smells to play back later
29 July 2006
NewScientist.com news service
Paul Marks

IMAGINE being able to record a smell and play it back later, just as you can with sounds or images.

Engineers at the Tokyo Institute of Technology in Japan are building an odour recorder capable of doing just that. Simply point the gadget at a freshly baked cookie, for example, and it will analyse its odour and reproduce it for you using a host of non-toxic chemicals.

"Point the gadget at a freshly baked cookie and it will reproduce the odour"The device could be used to improve online shopping by allowing you to sniff foods or fragrances before you buy, to add an extra dimension to virtual reality environments and even to assist military doctors treating soldiers remotely by recreating bile, blood or urine odours that might help a diagnosis.

While a number of companies have produced aroma generators designed to enhance computer games or TV shows, they have failed commercially because they have been very limited in the range of smells they can produce, says Pambuk Somboon of the Tokyo team.

So he has done away with pre-prepared smells and developed a system that records and later reproduces the odours. It's no easy task: "In video, you just need to record shades of red, green and blue," he says. "But humans have 347 olfactory sensors, so we need a lot of source chemicals."

Somboon's system will use 15 chemical-sensing microchips, or electronic noses, to pick up a broad range of aromas. These are then used to create a digital recipe from a set of 96 chemicals that can be chosen according to the purpose of each individual gadget. When you want to replay a smell, drops from the relevant vials are mixed, heated and vaporised. In tests so far, the system has successfully recorded and reproduced the smell of orange, lemon, apple, banana and melon. "We can even tell a green apple from a red apple," Somboon says. "

http://www.newscientisttech.com/article/mg19125586.300-device-records-smells-to-play-back-later.html

Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 03/07/2006 15:30:02
" Huge Asteroid to Fly Past Earth July 3
Joe Rao
SPACE.com Skywatching Columnist

An asteroid possibly as large as a half-mile or more in diameter is rapidly approaching the Earth.  There is no need for concern, for no collision is in the offing, but the space rock will make an exceptionally close approach to our planet early on Monday, July 3, passing just beyond the Moon's average distance from Earth.  

Astronomers will attempt to get a more accurate assessment of the asteroid's size by “pinging” it with radar.  

And skywatchers with good telescopes and some experience just might be able to get a glimpse of this cosmic rock as it streaks rapidly past our planet in the wee hours Monday. The closest approach occurs late Sunday for U.S. West Coast skywatchers.

The asteroid, designated 2004 XP14, was discovered on Dec. 10, 2004 by the Lincoln Laboratory Near Earth Asteroid Research (LINEAR), a continuing camera survey to keep watch for asteroids that may pass uncomfortably close to Earth.  

Although initially there were concerns that this asteroid might possibly impact Earth later this century and thus merit special monitoring, further analysis of its orbit has since ruled out any such collision, at least in the foreseeable future.  

Asteroid 2004 XP14 is a member of a class of asteroids known as Apollo, which have Earth-crossing orbits. The name comes from 1862 Apollo, the first asteroid of this group to be discovered. There are now 1,989 known Apollos.

The size of 2004 XP 14 is not precisely known. But based on its brightness, the diameter is believed to be somewhere in the range of 1,345 to 3,018-feet  (410 to 920 meters). That's between a quarter mile and just over a half-mile wide.

Due to the proximity of its orbit to Earth and its estimated size, this object has been classified as a “Potentially Hazardous Asteroid” (PNA) by the Minor Planet Center in Cambridge, Massachusetts. There are currently 783 PNAs.

The latest calculations show that 2004 XP14 will pass closest to Earth at 04:25 UT on July 3 (12:25 a.m. EDT or 9:25 p.m. PDT on July 2).  The asteroid's distance from Earth at that moment will be 268,624-miles (432,308 km), or just 1.1 times the Moon's average distance from Earth. Spotting 2004 XP14 will be a challenge, best accomplished by seasoned observers with moderate-sized telescopes. "

http://news.yahoo.com/s/space/20060626/sc_space/hugeasteroidtoflypastearthjuly3
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 03/07/2006 17:53:22
" Device records smells to play back later
29 July 2006
NewScientist.com news service
Paul Marks

IMAGINE being able to record a smell and play it back later, just as you can with sounds or images.

Engineers at the Tokyo Institute of Technology in Japan are building an odour recorder capable of doing just that. Simply point the gadget at a freshly baked cookie, for example, and it will analyse its odour and reproduce it for you using a host of non-toxic chemicals.

"Point the gadget at a freshly baked cookie and it will reproduce the odour"The device could be used to improve online shopping by allowing you to sniff foods or fragrances before you buy, to add an extra dimension to virtual reality environments and even to assist military doctors treating soldiers remotely by recreating bile, blood or urine odours that might help a diagnosis.

While a number of companies have produced aroma generators designed to enhance computer games or TV shows, they have failed commercially because they have been very limited in the range of smells they can produce, says Pambuk Somboon of the Tokyo team.

So he has done away with pre-prepared smells and developed a system that records and later reproduces the odours. It's no easy task: "In video, you just need to record shades of red, green and blue," he says. "But humans have 347 olfactory sensors, so we need a lot of source chemicals."

Somboon's system will use 15 chemical-sensing microchips, or electronic noses, to pick up a broad range of aromas. These are then used to create a digital recipe from a set of 96 chemicals that can be chosen according to the purpose of each individual gadget. When you want to replay a smell, drops from the relevant vials are mixed, heated and vaporised. In tests so far, the system has successfully recorded and reproduced the smell of orange, lemon, apple, banana and melon. "We can even tell a green apple from a red apple," Somboon says. "

http://www.newscientisttech.com/article/mg19125586.300-device-records-smells-to-play-back-later.html

Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 19/07/2006 18:30:46
IT'S HOT HOT HOT !!

Britain is experiencing the hottest day of the year so far with temperatures forecast to rocket to 36C (96.8F).

Experts said the heatwave will show no sign of relenting as hot winds from France boost temperatures further.

Monday and Tuesday have already seen the two hottest days of the year so far with temperatures of up to 33.2C (91.8F).

Weathermen said the highest temperatures will be recorded in the area west of London, north of Bristol and south of Birmingham.

If the mercury does reach 36C it will match the hottest July day, set on July 22, 1911, in Epsom, Surrey.

The highest UK temperature ever recorded was 38.5C (101.3F) in Faversham, Kent, on August 10, 2003.

British temperatures this week have outstripped popular holiday destinations including Athens, Bermuda, Rio de Janeiro and Rome.

Forecasters expect a bank of showers coming in from the South West to offer some respite tonight and tomorrow, but the weekend should still be very warm.

The heatwave has sparked a series of health warnings over fears for the safety of elderly and vulnerable people.

And police have issued a safety warning after a teenager drowned as he cooled off in a canal.

The 14-year-old boy died after jumping into the water in Glen Parva, Leicester.

Police confirmed the death was a "tragic accident" and have referred the case to the coroner.

A spokeswoman said: "The assumption is that, because of the heat, the boy entered the water to cool down."

Officers, in association with British Waterways, have issued a warning to people who might be tempted to swim in rivers and lakes as temperatures rocket.

Jeff Whyatt, general manager of British Waterways South East, said: "There are a lot of hidden dangers in open water and even the strongest swimmers can experience difficulty.

"This sad and tragic accident highlights the real risks of swimming in the canal.

"We understand how inviting the water may look on a warm day but it's important to stress that swimming in any waterways is extremely dangerous.

"The water is frequently far colder than expected and can lead to muscle cramps in even the strongest of swimmers.

"Submerged objects pose further dangers and underwater currents on rivers, or those created by passing boats, are hazardous.

"And it's particularly important over the summer to ensure that children are always supervised when near to water."

SOURCE..YAHOO.CO.UK

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 19/07/2006 18:35:24
Mystery of Explosive Star Solved
In February, a faint star a few thousand light-years away flared suddenly, beaming so brightly that for a few days it was visible to the naked eye.

The star is a stellar corpse the size of Earth, known as a white dwarf, and it is paired in a binary system with a red giant, a dying, bloated star that once resembled our Sun. The red giant has been dumping gas onto the surface of the white dwarf, and every few years, enough matter accumulates to set off a giant thermonuclear explosion.

It was one of these explosions, called a "nova," that astronomers and stargazers detected earlier this year.

The two-star system, called RS Ophiuchi, is known as a recurrent nova because five similar eruptions have been detected before. The first observation occurred in 1898; the last eruption prior to this latest one happened in 1985.

The new observations, made using advanced radio and X-ray telescopes not available during the last outburst, reveal the explosion to be more complex than was previously assumed.

Standard computer models had predicted a spherical explosion with matter ejected in all directions equally. The latest observations instead showed that the explosion evolved into two lobes, confirming suspicions that the nova outburst produces twin jets of stellar material that spews out from the white dwarf in opposite directions.

"The radio images represent the first time we've ever seen the birth of a jet in a white dwarf system. We literally see the jet 'turn on,'" said Michael Rupen, an astronomer at the National Radio Astronomy Observatory who studied RS Ophiuchi using the Very Long Baseline Array (VLBA).

As impressive as the nova are, they might just be precursors for a more violent supernova explosion that will occur in the future, scientists say.

Like the Sun, Only More Powerful
 

The white dwarf's thermonuclear blasts are similar to those that occur on the surface of the sun, but they can be over 100,000 times more powerful. During each outburst, an amount of gas equal to the mass of the Earth is flung into space. Some of this ejected matter slams into the extended atmosphere of the inflated red giant, creating blast waves that accelerate electrons to nearly the speed of light. As the electrons travel through the stars' magnetic fields, they emit radio waves that can be detected by telescopes on Earth.

The blast waves move at over four million miles (about 6.4 million km) per hour. For a few weeks during each outburst, the white dwarf becomes a red giant.

"After the [thermonuclear explosion], the white dwarf will puff up into a red giant for a few weeks as the hydrogen that has been blasted into space fuses into helium," explains Richard Barry of the NASA Goddard Space Flight Center in Maryland.

All eyes on Ophiuchi

Japanese astronomers first detected signs of RS Ophiuchi's latest nova on the night of Feb. 12. Follow-up observations by radio telescopes revealed an expanding blast wave whose diameter was already the size of Saturn's orbit around the Sun.

In the weeks following, several radio and X-ray telescopes around the world tracked RS Ophiuchi closely, including the MERLIN array in the UK, the European EVN array, the Very Long Baseline Array (VLBA) and Very Large Array (VLA) in the United States, and NASA's Swift and Rossi X-ray Timing Explorer satellites.

Findings from the Rossi X-ray Timing Explorer and the VLBA/EVN observations are detailed in two separate studies published in the July 20 issue of the journal Nature.

The red giant and white dwarf stars making up RS Ophiuchi are separated by about 1.5 astronomical units, or one and a half times the distance the Earth is from the sun. The binary star system is located in the constellation Ophiuchus, about 5,000 light-years away—very close by astronomical standards.

"We have a ringside seat for this very important event," Barry told SPACE.com. Barry is a co-author on another study on RS Ophiuchi that will appear in an upcoming edition of Astrophysical Journal.

Supernova precursor?

When the outburst is over, gas will once again build up on the white dwarf and the explosions will begin anew, perhaps in some 20 years time. It's unknown whether the white dwarf casts off all of its accumulated matter during each eruption, or whether some of the material is being hoarded and slowly increasing the mass of the dead star.

"If the white dwarf is increasing in mass then it will eventually be ripped apart in a titanic supernova explosion and the cycle of outbursts will come to an end," said Tim O'Brien of the University of Manchester, a co-author on one of the Nature studies.

White dwarfs must attain a critical 1.4 solar masses before they can explode in what scientists call a Type 1a supernova. The white dwarf in RS Ophiuchi is near this critical limit now, but it will still probably need hundreds of thousands of years to accumulate the final bit of mass, scientists say.

Because all Type 1a supernovas emit the same amount of light at their peak, they serve as important "standard candles" which astronomers use to calculate cosmic distances.

"Our understanding of these objects is exceedingly important as any miscalculation or uncertainty in the total light of output of supernovae could have a dramatic effect on our calculations of the scale and size of the entire universe," Barry said.
SOURCE. NASA

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 27/07/2006 13:48:09
"Spine doctors raise hope of electric wound cure:
 scientists from the University of Aberdeen in Scotland have found a new way to heal serious wounds, including broken spinal cords. The technique - stimulating injuries with electrical currents - has been used in an operation that produced dramatic improvements in patients paralysed by spinal injuries. After inserting battery packs beside their broken spinal cords in clinical trials, many patients had feelings restored to their legs and arms after a few weeks’ treatment. Professor Colin McCaig, head of the university’s school of medical sciences, says that in a few years, everyone could have an electrical device for ‘speeding up healing’ in their first aid box.
(Source: The Observer, May 29, 2005. For further information see: www.aberdeen.ac.uk)"
http://www.educationuk.org.my/News_digest/Jun2005.html

Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 27/07/2006 13:52:56
" Gecko inspires sticky tape

By Richard Black
BBC science correspondent  

Scientists in the UK have created a sticky tape which works in the same way as gecko feet.
 
Geckos are known for their climbing prowess
The researchers say the material clings so well to a surface that by covering the palm of one hand with the tape, a person could hang from the ceiling - just like the remarkable lizard.

So far, however, Professor Andre Geim and colleagues have only been able to make a very small square of their gecko tape because of the difficulties involved in the fabrication process.

Nonetheless, the University of Manchester scientists are confident they can refine their work so that commercial quantities of the new sticky material can be produced. ".
http://news.bbc.co.uk/1/hi/sci/tech/2953852.stm

 
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 27/07/2006 13:48:09
"Spine doctors raise hope of electric wound cure:
 scientists from the University of Aberdeen in Scotland have found a new way to heal serious wounds, including broken spinal cords. The technique - stimulating injuries with electrical currents - has been used in an operation that produced dramatic improvements in patients paralysed by spinal injuries. After inserting battery packs beside their broken spinal cords in clinical trials, many patients had feelings restored to their legs and arms after a few weeks’ treatment. Professor Colin McCaig, head of the university’s school of medical sciences, says that in a few years, everyone could have an electrical device for ‘speeding up healing’ in their first aid box.
(Source: The Observer, May 29, 2005. For further information see: www.aberdeen.ac.uk)"
http://www.educationuk.org.my/News_digest/Jun2005.html

Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 27/07/2006 13:52:56
" Gecko inspires sticky tape

By Richard Black
BBC science correspondent  

Scientists in the UK have created a sticky tape which works in the same way as gecko feet.
 
Geckos are known for their climbing prowess
The researchers say the material clings so well to a surface that by covering the palm of one hand with the tape, a person could hang from the ceiling - just like the remarkable lizard.

So far, however, Professor Andre Geim and colleagues have only been able to make a very small square of their gecko tape because of the difficulties involved in the fabrication process.

Nonetheless, the University of Manchester scientists are confident they can refine their work so that commercial quantities of the new sticky material can be produced. ".
http://news.bbc.co.uk/1/hi/sci/tech/2953852.stm

 
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 02/08/2006 12:22:02
" Biological versus nonbiological older brothers and men’s sexual orientation "

Anthony F. Bogaert  
Departments of Community Health Sciences and Psychology, Brock University, St. Catharines, ON, Canada L2S 3A1

The most consistent biodemographic correlate of sexual orientation in men is the number of older brothers (fraternal birth order). The mechanism underlying this effect remains unknown. In this article, I provide a direct test pitting prenatal against postnatal (e.g., social/rearing) mechanisms. Four samples of homosexual and heterosexual men (total n = 944), including one sample of men raised in nonbiological and blended families (e.g., raised with half- or step-siblings or as adoptees) were studied. Only biological older brothers, and not any other sibling characteristic, including nonbiological older brothers, predicted men’s sexual orientation, regardless of the amount of time reared with these siblings. These results strongly suggest a prenatal origin to the fraternal birth-order effect ".

http://www.pnas.org/cgi/content/abstract/0511152103v1

Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 02/08/2006 12:59:08
" The Sunday Times July 30, 2006

Beautiful people tend to have girls, say scientists

Roger Dobson and Yuba Bessaoud
 
HOLLYWOOD’S most beautiful couple, Brad Pitt and Angelina Jolie, are in the grip of evolutionary forces that made it almost inevitable that their child would be a girl.
According to research, attractive parents are 26% more likely to have a daughter than a son as their first child. It is an inexorable process that has resulted in women becoming increasingly more attractive than men.  
 
This is because of differing “evolutionary strategies” that each sex has adopted to survive, claim researchers at the London School of Economics.

While reproductive success for males depends largely on the status of the father (as sons from higher-status families inherit their position and are in turn able to protect and invest in their offspring), daughters’ reproductive successes mostly depend on their youth and attractiveness. “We have shown two things,” said Dr Satoshi Kanazawa, who led the research. “Beautiful parents have more daughters than ugly parents, because physical attractiveness is heritable and because daughters benefit from attractiveness more than sons.

“We have also shown that women on average are more attractive than men, because over evolutionary history the slight bias of beautiful parents to have more daughters has accumulated, so that girls have become more and more attractive than boys.”

Men prefer younger and physically more attractive women for their mates. A potential mate’s status or wealth is far less important for men than her youth and physical attractiveness, argues the report.

The research, in the Journal of Theoretical Biology, analysed more than 20,000 people in America. Researchers rated their beauty according to height, weight and apparent age, all factors that can be used to judge basic attraction levels without subjective viewpoints. Only first-born children were included in the analysis.

Dr Mark Thomas, senior lecturer at the biology department of University College London, said the LSE’s results appeared to “fit in” with the state of research on sexual evolution.

He said the phenomenon was rooted in men’s natural promiscuity, noting: “Females can only reproduce so many times in their lives whereas for men, theoretically, the limit is all of the females in the world times the number of reproductive opportunities (those females) have.”

Besides Pitt and Jolie, who named their daughter Shiloh Nouvel, the Hollywood couple Reese Witherspoon and Ryan Phillippe, whose first-born daughter Ava is six, lend weight to the theory. "

http://www.timesonline.co.uk/newspaper/0,,176-2291737,00.html
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 10/08/2006 13:29:42
" Curry May Help Prevent Colon Cancer
Wed Aug 2, 11:54 PM ET

WEDNESDAY, Aug. 2 (HealthDay News) -- Chemicals found in onions and curry may help prevent colon cancer, a Johns Hopkins University School of Medicine study suggests.
 
Published in the August issue of the journal Clinical Gastroenterology and Hepatology, the study included five people with familial adenomatous polyposis (FAP), an inherited form of precancerous polyps in the lower bowel. FAP is characterized by the development of hundreds of colorectal polyps and eventual colon cancer.

For an average of six months, the patients received three daily oral doses of 20 milligrams of quercetin (an antioxidant found in onions) and 480 milligrams of curcumin (found in tumeric, one of the main ingredients of curry).

The average number of polyps in the patients declined by 60.4 percent, and the average size of the polyps decreased by 50.9 percent, the study said.

"We believe this is the first proof of principle that these substances have significant effects in patients with FAP," study leader Dr. Francis M. Giardiello, director of the division of gastroenterology at the university, said in a prepared statement.

He believes that curcumin is the key agent.

"The amount of quercetin we administered was similar to what many people consume daily; however, the amount of curcumin is many times what a person might ingest in a typical diet, since tumeric only contains on average three percent to five percent curcumin by weight," Giardiello said.

It's not likely that simply eating onions and curry would provide the same benefits seen in this study, he noted.

The researchers plan to conduct a randomized clinical trial with more patients. "
http://news.yahoo.com/s/hsn/20060803/hl_hsn/currymayhelppreventcoloncancer;_ylt=AtoHk66v.GEptsaG5yH7wtLVJRIF;_ylu=X3oDMTA0cDJlYmhvBHNlYwM-
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 10/08/2006 20:41:26
As you may or may not know I just luff to stroke bees so I was pleased to find this non-stroking but BEE related news article.



Bees get a buzz from warm flowers
Bumblebees prefer to visit warm flowers and can use colour to predict the bloom's temperature, research suggests.

The findings challenge the long-held belief that the insects seek out flowers that contain the most nectar or pollen.

UK researchers say the bees might use warmer blooms to help maintain their body temperatures and save energy.

The study by scientists from Cambridge University and Queen Mary College is published in the journal Nature.

Flower power

To test whether bumblebees (Bombus terrestris) could use colour to identify warmer flowers, the team used a variety of differently coloured artificial plants.

In a "foraging bout" the creatures were given a choice between four purple flowers or four slightly cooler pink ones that were placed in a random order.

In one test, 58% of the bees chose the warmer purple flowers. When the colours were switched and warm nectar was placed in the pink petals, 61.6% headed for the pink blooms.

Lars Chittka, from Queen Mary College, University of London, and a co-author of the paper, said the tests showed that bees preferred warmer plants and could learn to identify the hotter species by the colour of flowers.

  Seeking out flowers with warmer nectar is a direct metabolic reward

Professor Lars Chittka

"If we do not give the bees any cues by which they can identify the warmer flowers then they fail the task. If the flowers are visually identical then they will visit them all.

"What the bees need to do is collect individual experience," Professor Chittka said. "They have to probe the flowers, learn which ones have higher temperatures and then to identify them they use colours or spatial positions."

The team suggests that the temperature can serve as an additional reward from pollinating insects in a context where there are also nutritional rewards available.

"Bees need to warm up to fly, they need to have body temperatures of at least 30C (86F)," Professor Chittka said.

If the air temperature was relatively cold, it took a considerable amount of the insects' energy reserves to reach this temperature, he added.

"In that sense, seeking out flowers with warmer nectar is a direct metabolic reward; it supplies them with energy that they would otherwise have to invest."

'Clever trick'

The researchers believe the findings could also affect the current understanding surrounding the evolutionary link between plants and pollinators.

"About 80% of flower species have a peculiar structure in their flowers; the skin is made up of little cells that are cone-shaped. It has never been fully understood what function they served," Professor Chittka said.

"But one effect it does have is that the cones act as little lenses to focus light directly into the parts of the cells that contain the floral pigment; because more light is absorbed it warms the flowers - that's a clever trick.

"We think the fact that 80% of floral species have this, it could be a broad evolutionary innovation in order to generate warmth and thus lure pollinators to collaborate with them," he suggested.

Professor Chittka's co-authors on the paper were Adrian Dyer, Heather Whitney, Sarah Arnold and Beverley Glover from Cambridge University's Department of Plant Science.


Source: BBC.CO.UK








Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Mjhavok on 15/08/2006 18:25:11
Japanese Researcher Ponders Reviving Woolly Mammoth

WASHINGTON (AP)—Descendants of extinct mammals like the giant woolly mammoth might one day walk the Earth again. It isn't exactly Jurassic Park, but Japanese researchers are looking at the possibility of using sperm from frozen animals to inseminate living relatives.

So far they've succeeded with mice—some frozen as long as 15 years—and lead researcher Dr. Atsuo Ogura says he would like to try experiments in larger animals.

"In this study, the rates of success with sperm from 15 year-frozen bodies were much higher than we expected. So the likelihood of mammoths revival would be higher than we expected before,'' Ogura said in an interview via e-mail.

While frozen sperm is commonly used by sperm banks, the team led by Ogura, at Riken Bioresource Center in Ibaraki, Japan, worked with sperm from whole frozen mice and from frozen mouse organs.

"If spermatozoa of extinct mammalian species can be retrieved from animal bodies that were kept frozen for millions of years in permafrost, live animals might be restored by injecting them into (eggs) from females of closely related species,'' the researchers said in a paper appearing in Tuesday's issue of Proceedings of the National Academy of Sciences.

Intact mammoth bodies have been excavated from Siberian permafrost.

Dr. Robert W. McGaughey, laboratory director at the Institute for Reproductive Studies in Scottsdale, Ariz., commented that since some of the whole frozen mice had been held for 15 years before obtaining the sperm nuclei "it clearly is possible that some day we may be able to obtain offspring from extinct animals frozen at reasonable temperatures for very long periods of time.''

The downside, added McGaughey, who was not part of the research team, is that an extinct animal probably would have to have been continuously maintained at a low temperature to avoid thawing/refreezing damage.

Elephants would be a potential candidate for insemination with frozen mammoth sperm, Ogura said. He also suggested experiments might be tried with extinct feline species and their modern relatives.

Less enthusiastic was Dr. Peter Mazur, a biologist at the University of Tennessee who has worked with frozen eggs and sperm and is a past president of the Society for Cryobiology.

Mazur thinks the chance that frozen sperm from mammoths could be used to fertilize a related species is near zero.

"The storage temperature of frozen mammoths is not nearly low enough to prevent the chemical degradation of their DNA over hundreds of thousands of years,'' he commented. And "even if the temperature were low enough to prevent chemical degradation, that would not prevent serious damage over those time periods from background radiation, which includes cosmic rays.''

Bringing back extinct species is an interesting suggestion, Dr. Douglas E. Chandler of the Arizona State University School of Life Sciences commented.

"The trick however is to find an acceptable species that would act as the mother,'' added Chandler, who was not part of Ogura's research team. If an elephant egg were used "the offspring would not be a mammoth but a hybrid between an elephant and a mammoth. If one wanted a true mammoth one would have to find a source of viable mammoth (eggs) to fertilize and implant and this is a much dicier proposition.''

McGaughey agreed, "It is unlikely eggs from such frozen animals would survive; therefore only the sperm would be available to put into eggs from an existing and appropriate modern mammal to approximate the extinct one.''

The research requires considerable technical expertise, Chandler said, adding that Ryuzo Yanagimachi, one of Ogura's researchers, "is a long time worker in this field and is highly respected. He and his colleagues clearly are experts appropriate for this work.''

Ogura's research was funded by the Japanese ministries of education and health, and the Human Science Foundation of Japan.

Steven
_______________________________________________________________
In a time of universal deceit - telling the truth is a revolutionary act.
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 15/08/2006 22:13:41
Excellent Steve...keep em coming.

Don't forget to credit the source.

Oops...sorry STEVEN !! [:)]


Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 16/08/2006 12:44:37
" World now has more fat people than hungry ones
Monday August 14, 10:22 AM     By Lawrence Bartlett
 
SYDNEY (AFP) - The world now has more overweight people than hungry ones and governments should design economic strategies to influence national diets, a conference of international experts have heard.

The transition from a starving world to an obese one had happened with dramatic speed, US professor Barry Popkin told the annual conference of the International Association of Agricultural Economists on Monday.

"The reality is that globally far more obesity than undernutrition exists,"

Popkin said, adding that while hunger was slowly declining, obesity was rapidly spreading.

There are more than a billion overweight people in the world and 800 million who are undernourished, he said at the Gold Coast convention centre near Brisbane. The world population is estimated at about 6.5 billion.

"Obesity is the norm globally and undernutrition, while still important in a few countries and in targeted populations in many others, is no longer the dominant disease."

The "burden of obesity", with its related illnesses, was also shifting from the rich to the poor, not only in urban but in rural areas around the world, he said.

China typified the changes, with a major shift in diet from cereals to animal products and vegetable oils accompanied by a decline in physical work, more motorised transport and more television viewing.

But all countries had failed to address the obesity "boom", the University of North Carolina professor said.

Food prices could be used to manipulate people's diets and tilt them towards healthier options, he suggested.

"For instance, if we charge money for every calorie of soft drink and fruit drink that was consumed, people would consume less of it.

"If we subsidise fruit and vegetable production, people would consume more of it and we would have a healthier diet." "
http://uk.news.yahoo.com/14082006/323/world-fat-people-hungry-ones-expert.html
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 16/08/2006 14:16:23
Bacteria can help predict ocean change
Marine bacteria groups vary predictably with ocean conditions

Every creature has its place and role in the oceans – even the smallest microbe, according to a new study that may lead to more accurate models of ocean change.

Scientists have long endorsed the concept of a unique biological niche for most animals and plants – a shark, for example, has a different role than a dolphin.

Bacteria instead have been relegated to an also-ran world of "functional redundancy" in which few species are considered unique, said Jed Fuhrman, holder of the McCulloch-Crosby Chair in Marine Biology in the USC College of Letters, Arts and Sciences.

In The Proceedings of the National Academy of Sciences' Early Edition, Fuhrman and colleagues from USC and Columbia University show that most kinds of bacteria are not interchangeable and that each thrives under predictable conditions and at predictable times.

Conversely, the kinds and numbers of bacteria in a sample can show where and when it was taken.

"I could tell you what month it is if you just got me a sample of water from out there," Fuhrman said.

The researchers took monthly bacteria samples for more than four years in the Pacific Ocean near the USC Wrigley Institute's marine laboratory on Catalina Island.

They used statistical methods to correlate the bacteria counts with the Wrigley Institute's monthly measurements of water temperature, salinity, nutrient content, plant matter and other variables.

The researchers found they could predict the makeup of the bacterial population by the conditions in the water more than four times in five.

A majority of bacterial species came and went predictably, Fuhrman said. A smaller "wild card" group in each sample was not predictable and could represent the bacterial equivalent of weeds and other redundant plants.

"Wherever we looked, we found predictable kinds, but within the groups there were always less predictable and more predictable members," Fuhrman said.

"They're just like animals and plants in the way they function in the system. Each one has its own place."

The findings have immediate relevance for scientists attempting to understand how the oceans are changing, Fuhrman said. If bacteria behave predictably, they can be used to improve models for ocean change.

By including bacteria, which make up the vast majority of species on land and sea, "we have some hope of predicting how changes are going to happen," Fuhrman said.

SOURCE: EUREKALERT.ORG

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 23/08/2006 15:54:51
" NASA Announces Dark Matter Discovery

Astronomers who used NASA's Chandra X-ray Observatory will host a media teleconference at 1 p.m. EDT Monday,
 Aug. 21, to announce how dark and normal matter have been forced apart in an extraordinarily energetic collision.

Shortly before the start of the briefing, images and graphics about the research will be posted at:
http://chandra.harvard.edu/photo/2006/1e0657/  "

http://www.nasa.gov/home/hqnews/2006/aug/HQ_M06128_dark_matter.html
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 23/08/2006 18:13:33
Robert !!...sorry but I was just about to paste all that is in my clipboard about the very item you have just posted about...

oooh...what to do...my clipboard is brimming with all this text...

Ok..I will paste it..

Thanks Robert...hope you don't mind:



NASA finds direct proof of that dark matter exists
NASA NEWS RELEASE
Posted: August 21, 2006


Dark matter and normal matter have been wrenched apart by the tremendous collision of two large clusters of galaxies. The discovery, using NASA's Chandra X-ray Observatory and other telescopes, gives direct evidence for the existence of dark matter.

"This is the most energetic cosmic event, besides the Big Bang, which we know about," said team member Maxim Markevitch of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass.

These observations provide the strongest evidence yet that most of the matter in the universe is dark. Despite considerable evidence for dark matter, some scientists have proposed alternative theories for gravity where it is stronger on intergalactic scales than predicted by Newton and Einstein, removing the need for dark matter. However, such theories cannot explain the observed effects of this collision.

"A universe that's dominated by dark stuff seems preposterous, so we wanted to test whether there were any basic flaws in our thinking," said Doug Clowe of the University of Arizona at Tucson, and leader of the study. "These results are direct proof that dark matter exists."

In galaxy clusters, the normal matter, like the atoms that make up the stars, planets, and everything on Earth, is primarily in the form of hot gas and stars. The mass of the hot gas between the galaxies is far greater than the mass of the stars in all of the galaxies. This normal matter is bound in the cluster by the gravity of an even greater mass of dark matter. Without dark matter, which is invisible and can only be detected through its gravity, the fast-moving galaxies and the hot gas would quickly fly apart.

The team was granted more than 100 hours on the Chandra telescope to observe the galaxy cluster 1E0657-56. The cluster is also known as the bullet cluster, because it contains a spectacular bullet-shaped cloud of hundred-million-degree gas. The X-ray image shows the bullet shape is due to a wind produced by the high-speed collision of a smaller cluster with a larger one.

In addition to the Chandra observation, the Hubble Space Telescope, the European Southern Observatory's Very Large Telescope and the Magellan optical telescopes were used to determine the location of the mass in the clusters. This was done by measuring the effect of gravitational lensing, where gravity from the clusters distorts light from background galaxies as predicted by Einstein's theory of general relativity.

The hot gas in this collision was slowed by a drag force, similar to air resistance. In contrast, the dark matter was not slowed by the impact, because it does not interact directly with itself or the gas except through gravity. This produced the separation of the dark and normal matter seen in the data. If hot gas was the most massive component in the clusters, as proposed by alternative gravity theories, such a separation would not have been seen. Instead, dark matter is required.

"This is the type of result that future theories will have to take into account," said Sean Carroll, a cosmologist at the University of Chicago, who was not involved with the study. "As we move forward to understand the true nature of dark matter, this new result will be impossible to ignore."

This result also gives scientists more confidence that the Newtonian gravity familiar on Earth and in the solar system also works on the huge scales of galaxy clusters.

"We've closed this loophole about gravity, and we've come closer than ever to seeing this invisible matter," Clowe said.

These results are being published in an upcoming issue of The Astrophysical Journal Letters. NASA's Marshall Space Flight Center, Huntsville, Ala., manages the Chandra program. The Smithsonian Astrophysical Observatory controls science and flight operations from the Chandra X-ray Center, Cambridge, Mass.


SOURCE: SPACELIGHTNOW.COM

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ariel on 23/08/2006 22:37:38
Kangaroo Pill to thin numbers

Wednesday, August 23, 2006; Posted: 9:50 a.m. EDT (13:50 GMT)

A female kangaroo seen recently in suburban Sydney.
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi.a.cnn.net%2Fcnn%2F2006%2FWORLD%2Fasiapcf%2F08%2F23%2Fkangaroo.contraceptive.ap%2Flong.kangaroo.ap.jpg&hash=9bb2f9b9d3a5f44ae694034c0cdedb04)

CANBERRA, Australia (AP) -- Scientists are hoping to develop an oral contraceptive for female kangaroos that will keep pouches empty as they hop around the national capital's grassy fringes.

Government ecologist Don Fletcher said Wednesday the oral contraceptive method promised to be more efficient than existing technology for curbing roo numbers around Canberra such as vasectomies for males and injections for females because the fleet-footed marsupials would not need to be captured.

"Realistically, to deal with wild animals it has to be oral," said Fletcher, who is collaborating with Newcastle University scientists on the research.

"One of the challenges is finding kangaroo ice-cream," he said, referring to a food pellet that grass-munching roos will find irresistible.

Field tests of the contraceptive could be under way in two-to-five years, he said.

Kangaroos are an ever-present road hazard in Canberra, particularly in dry months when thousands bounce in from the surrounding countryside to feed on watered lawns and golf courses.

http://www.cnn.com/2006/WORLD/asiapcf/08/23/kangaroo.contraceptive.ap/index.html

(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi11.photobucket.com%2Falbums%2Fa196%2Fbariel%2Ffsm.jpg&hash=27b1c6663feeeee1f95650d42cca0927) ariel
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ukmicky on 24/08/2006 03:21:33
who responsible for going to wide and taking this page over the edge.

Michael
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Mjhavok on 24/08/2006 15:19:20
How the tongue tastes sour
Receptor found that is triggered by acidic foods.


By Lucy Heady

Researchers have worked out how a mammal's tongue detects sour tastes: it's all down to a single, specialized receptor, they say.

Taste in mammals is classified into sweet, salty, bitter, sour and umami (the taste of monosodium glutamate, commonly found in Chinese takeaways). Until now, only the sweet, bitter and umami taste receptors had been identified, and researchers were unsure whether the other two tastes had specialized receptors for them at all.

The three tastes with known receptors are triggered by large molecules, such as sucrose, that latch on to and are recognized by specialized cells on the tongue. But salty and sour are different in that they are the tastes of very simple ions: hydrogen ions (H+) for acidity and, mainly, sodium ions (Na+) for salt. Some researchers have speculated that many cells in the tongue might be able to pick up these signals, relaying the information in a complex pattern of nerve signals to the brain. "This kind of model is very messy," says Charles Zuker of the Howard Hughes Medical Institute in San Diego.

So Zuker's team — the same lab that pinned down the previous three taste receptors — set out to hunt for a sour taste receptor.

Angela Huang, a graduate student in Zuker's lab, first trawled through the mouse genome to pick out any proteins that exist in cell membranes: proteins that can pick up signals from the outside world and transmit them to nerves. That left about 10,000 candidates.

They screened these by assuming that a taste receptor would only be found in a small number of tissue types (specifically tongue taste cells). That whittled the list down to 900. They then looked for gene patterns known to exist in other taste receptors, leaving a single protein called PKD2L1 as a prime candidate.

To check on the action of PKD2L1, the team created genetically engineered mice that produced a toxin in cells expressing PKD2L1, killing these cells. Probes placed inside the mouse brains then showed that no neural activity was prompted by sour-tasting foods in these mice, they report in Nature1. And their behaviour changed to match: they kept licking sour foods, whereas normal mice would run away from acidic snacks (only humans have a taste for sour foods; other animals avoid them).

Sweet success

Zuker's team also hit upon a surprising fact about the sour receptor: it seems to show up in neurons of the spinal cord. "This is the first time that a taste receptor has been shown to respond to stimuli in another part of the body," says Zuker. This 'taste' sensor might help the body to monitor acidity in the nervous system, he says.

Another group of scientists who were similarly on the trail of a sour-taste receptor also hit upon PKD2L1 as a candidate. Hiroaki Matsunami from Duke University Medical Center in Durham, North Carolina, and colleagues showed PKD2L1 and PKD1L3 being activated by acid in mouse cells in the lab dish2. They also found that these proteins were well positioned on the tongue for contact with food, but were unable to confirm that there was just one dedicated receptor for sour taste. Zuker's work fills that gap.

The two studies together certainly seem to point the way to understanding sour taste, says Gary Beauchamp of the Monell Center in Philadelphia, Pennsylvania.

Taste test

But it seems that not everything is understood. Strangely, while taste is an instantaneous perception, Matsunami's work showed a delay between the introduction of acid and the cells firing off a 'sour' signal, says Zuker. This indicates that something else might be going on inside the mouth to help mammals identify the taste.

Beauchamp adds that it is also unclear how or why a sour receptor would come to be. There is a clear evolutionary motivation for the existence of some other taste receptors: bitterness detects poison and sweetness detects sugar, an essential source of energy. "It is still not entirely convincing why we need a sour taste receptor," says Beauchamp. "None of the suggestions for sour taste, such as being able to detect unripe fruits, are entirely compelling."

For Zucker's team, what comes next is a search for the salt receptor. "It's just a case of going through those proteins that are left behind when all the other taste receptors are gone," says Zuker.


Source - Nature

(http://www.nature.com/news/2006/060821/pf/060821-9_pf.html)

Steven
_______________________________________________________________
In a time of universal deceit - telling the truth is a revolutionary act.
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 23/08/2006 15:54:51
" NASA Announces Dark Matter Discovery

Astronomers who used NASA's Chandra X-ray Observatory will host a media teleconference at 1 p.m. EDT Monday,
 Aug. 21, to announce how dark and normal matter have been forced apart in an extraordinarily energetic collision.

Shortly before the start of the briefing, images and graphics about the research will be posted at:
http://chandra.harvard.edu/photo/2006/1e0657/  "

http://www.nasa.gov/home/hqnews/2006/aug/HQ_M06128_dark_matter.html
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 23/08/2006 18:13:33
Robert !!...sorry but I was just about to paste all that is in my clipboard about the very item you have just posted about...

oooh...what to do...my clipboard is brimming with all this text...

Ok..I will paste it..

Thanks Robert...hope you don't mind:



NASA finds direct proof of that dark matter exists
NASA NEWS RELEASE
Posted: August 21, 2006


Dark matter and normal matter have been wrenched apart by the tremendous collision of two large clusters of galaxies. The discovery, using NASA's Chandra X-ray Observatory and other telescopes, gives direct evidence for the existence of dark matter.

"This is the most energetic cosmic event, besides the Big Bang, which we know about," said team member Maxim Markevitch of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass.

These observations provide the strongest evidence yet that most of the matter in the universe is dark. Despite considerable evidence for dark matter, some scientists have proposed alternative theories for gravity where it is stronger on intergalactic scales than predicted by Newton and Einstein, removing the need for dark matter. However, such theories cannot explain the observed effects of this collision.

"A universe that's dominated by dark stuff seems preposterous, so we wanted to test whether there were any basic flaws in our thinking," said Doug Clowe of the University of Arizona at Tucson, and leader of the study. "These results are direct proof that dark matter exists."

In galaxy clusters, the normal matter, like the atoms that make up the stars, planets, and everything on Earth, is primarily in the form of hot gas and stars. The mass of the hot gas between the galaxies is far greater than the mass of the stars in all of the galaxies. This normal matter is bound in the cluster by the gravity of an even greater mass of dark matter. Without dark matter, which is invisible and can only be detected through its gravity, the fast-moving galaxies and the hot gas would quickly fly apart.

The team was granted more than 100 hours on the Chandra telescope to observe the galaxy cluster 1E0657-56. The cluster is also known as the bullet cluster, because it contains a spectacular bullet-shaped cloud of hundred-million-degree gas. The X-ray image shows the bullet shape is due to a wind produced by the high-speed collision of a smaller cluster with a larger one.

In addition to the Chandra observation, the Hubble Space Telescope, the European Southern Observatory's Very Large Telescope and the Magellan optical telescopes were used to determine the location of the mass in the clusters. This was done by measuring the effect of gravitational lensing, where gravity from the clusters distorts light from background galaxies as predicted by Einstein's theory of general relativity.

The hot gas in this collision was slowed by a drag force, similar to air resistance. In contrast, the dark matter was not slowed by the impact, because it does not interact directly with itself or the gas except through gravity. This produced the separation of the dark and normal matter seen in the data. If hot gas was the most massive component in the clusters, as proposed by alternative gravity theories, such a separation would not have been seen. Instead, dark matter is required.

"This is the type of result that future theories will have to take into account," said Sean Carroll, a cosmologist at the University of Chicago, who was not involved with the study. "As we move forward to understand the true nature of dark matter, this new result will be impossible to ignore."

This result also gives scientists more confidence that the Newtonian gravity familiar on Earth and in the solar system also works on the huge scales of galaxy clusters.

"We've closed this loophole about gravity, and we've come closer than ever to seeing this invisible matter," Clowe said.

These results are being published in an upcoming issue of The Astrophysical Journal Letters. NASA's Marshall Space Flight Center, Huntsville, Ala., manages the Chandra program. The Smithsonian Astrophysical Observatory controls science and flight operations from the Chandra X-ray Center, Cambridge, Mass.


SOURCE: SPACELIGHTNOW.COM

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 23/08/2006 15:54:51
" NASA Announces Dark Matter Discovery

Astronomers who used NASA's Chandra X-ray Observatory will host a media teleconference at 1 p.m. EDT Monday,
 Aug. 21, to announce how dark and normal matter have been forced apart in an extraordinarily energetic collision.

Shortly before the start of the briefing, images and graphics about the research will be posted at:
http://chandra.harvard.edu/photo/2006/1e0657/  "

http://www.nasa.gov/home/hqnews/2006/aug/HQ_M06128_dark_matter.html
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 23/08/2006 18:13:33
Robert !!...sorry but I was just about to paste all that is in my clipboard about the very item you have just posted about...

oooh...what to do...my clipboard is brimming with all this text...

Ok..I will paste it..

Thanks Robert...hope you don't mind:



NASA finds direct proof of that dark matter exists
NASA NEWS RELEASE
Posted: August 21, 2006


Dark matter and normal matter have been wrenched apart by the tremendous collision of two large clusters of galaxies. The discovery, using NASA's Chandra X-ray Observatory and other telescopes, gives direct evidence for the existence of dark matter.

"This is the most energetic cosmic event, besides the Big Bang, which we know about," said team member Maxim Markevitch of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass.

These observations provide the strongest evidence yet that most of the matter in the universe is dark. Despite considerable evidence for dark matter, some scientists have proposed alternative theories for gravity where it is stronger on intergalactic scales than predicted by Newton and Einstein, removing the need for dark matter. However, such theories cannot explain the observed effects of this collision.

"A universe that's dominated by dark stuff seems preposterous, so we wanted to test whether there were any basic flaws in our thinking," said Doug Clowe of the University of Arizona at Tucson, and leader of the study. "These results are direct proof that dark matter exists."

In galaxy clusters, the normal matter, like the atoms that make up the stars, planets, and everything on Earth, is primarily in the form of hot gas and stars. The mass of the hot gas between the galaxies is far greater than the mass of the stars in all of the galaxies. This normal matter is bound in the cluster by the gravity of an even greater mass of dark matter. Without dark matter, which is invisible and can only be detected through its gravity, the fast-moving galaxies and the hot gas would quickly fly apart.

The team was granted more than 100 hours on the Chandra telescope to observe the galaxy cluster 1E0657-56. The cluster is also known as the bullet cluster, because it contains a spectacular bullet-shaped cloud of hundred-million-degree gas. The X-ray image shows the bullet shape is due to a wind produced by the high-speed collision of a smaller cluster with a larger one.

In addition to the Chandra observation, the Hubble Space Telescope, the European Southern Observatory's Very Large Telescope and the Magellan optical telescopes were used to determine the location of the mass in the clusters. This was done by measuring the effect of gravitational lensing, where gravity from the clusters distorts light from background galaxies as predicted by Einstein's theory of general relativity.

The hot gas in this collision was slowed by a drag force, similar to air resistance. In contrast, the dark matter was not slowed by the impact, because it does not interact directly with itself or the gas except through gravity. This produced the separation of the dark and normal matter seen in the data. If hot gas was the most massive component in the clusters, as proposed by alternative gravity theories, such a separation would not have been seen. Instead, dark matter is required.

"This is the type of result that future theories will have to take into account," said Sean Carroll, a cosmologist at the University of Chicago, who was not involved with the study. "As we move forward to understand the true nature of dark matter, this new result will be impossible to ignore."

This result also gives scientists more confidence that the Newtonian gravity familiar on Earth and in the solar system also works on the huge scales of galaxy clusters.

"We've closed this loophole about gravity, and we've come closer than ever to seeing this invisible matter," Clowe said.

These results are being published in an upcoming issue of The Astrophysical Journal Letters. NASA's Marshall Space Flight Center, Huntsville, Ala., manages the Chandra program. The Smithsonian Astrophysical Observatory controls science and flight operations from the Chandra X-ray Center, Cambridge, Mass.


SOURCE: SPACELIGHTNOW.COM

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ariel on 23/08/2006 22:37:38
Kangaroo Pill to thin numbers

Wednesday, August 23, 2006; Posted: 9:50 a.m. EDT (13:50 GMT)

A female kangaroo seen recently in suburban Sydney.
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi.a.cnn.net%2Fcnn%2F2006%2FWORLD%2Fasiapcf%2F08%2F23%2Fkangaroo.contraceptive.ap%2Flong.kangaroo.ap.jpg&hash=9bb2f9b9d3a5f44ae694034c0cdedb04)

CANBERRA, Australia (AP) -- Scientists are hoping to develop an oral contraceptive for female kangaroos that will keep pouches empty as they hop around the national capital's grassy fringes.

Government ecologist Don Fletcher said Wednesday the oral contraceptive method promised to be more efficient than existing technology for curbing roo numbers around Canberra such as vasectomies for males and injections for females because the fleet-footed marsupials would not need to be captured.

"Realistically, to deal with wild animals it has to be oral," said Fletcher, who is collaborating with Newcastle University scientists on the research.

"One of the challenges is finding kangaroo ice-cream," he said, referring to a food pellet that grass-munching roos will find irresistible.

Field tests of the contraceptive could be under way in two-to-five years, he said.

Kangaroos are an ever-present road hazard in Canberra, particularly in dry months when thousands bounce in from the surrounding countryside to feed on watered lawns and golf courses.

http://www.cnn.com/2006/WORLD/asiapcf/08/23/kangaroo.contraceptive.ap/index.html

(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi11.photobucket.com%2Falbums%2Fa196%2Fbariel%2Ffsm.jpg&hash=27b1c6663feeeee1f95650d42cca0927) ariel
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ukmicky on 24/08/2006 03:21:33
who responsible for going to wide and taking this page over the edge.

Michael
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Mjhavok on 24/08/2006 15:19:20
How the tongue tastes sour
Receptor found that is triggered by acidic foods.


By Lucy Heady

Researchers have worked out how a mammal's tongue detects sour tastes: it's all down to a single, specialized receptor, they say.

Taste in mammals is classified into sweet, salty, bitter, sour and umami (the taste of monosodium glutamate, commonly found in Chinese takeaways). Until now, only the sweet, bitter and umami taste receptors had been identified, and researchers were unsure whether the other two tastes had specialized receptors for them at all.

The three tastes with known receptors are triggered by large molecules, such as sucrose, that latch on to and are recognized by specialized cells on the tongue. But salty and sour are different in that they are the tastes of very simple ions: hydrogen ions (H+) for acidity and, mainly, sodium ions (Na+) for salt. Some researchers have speculated that many cells in the tongue might be able to pick up these signals, relaying the information in a complex pattern of nerve signals to the brain. "This kind of model is very messy," says Charles Zuker of the Howard Hughes Medical Institute in San Diego.

So Zuker's team — the same lab that pinned down the previous three taste receptors — set out to hunt for a sour taste receptor.

Angela Huang, a graduate student in Zuker's lab, first trawled through the mouse genome to pick out any proteins that exist in cell membranes: proteins that can pick up signals from the outside world and transmit them to nerves. That left about 10,000 candidates.

They screened these by assuming that a taste receptor would only be found in a small number of tissue types (specifically tongue taste cells). That whittled the list down to 900. They then looked for gene patterns known to exist in other taste receptors, leaving a single protein called PKD2L1 as a prime candidate.

To check on the action of PKD2L1, the team created genetically engineered mice that produced a toxin in cells expressing PKD2L1, killing these cells. Probes placed inside the mouse brains then showed that no neural activity was prompted by sour-tasting foods in these mice, they report in Nature1. And their behaviour changed to match: they kept licking sour foods, whereas normal mice would run away from acidic snacks (only humans have a taste for sour foods; other animals avoid them).

Sweet success

Zuker's team also hit upon a surprising fact about the sour receptor: it seems to show up in neurons of the spinal cord. "This is the first time that a taste receptor has been shown to respond to stimuli in another part of the body," says Zuker. This 'taste' sensor might help the body to monitor acidity in the nervous system, he says.

Another group of scientists who were similarly on the trail of a sour-taste receptor also hit upon PKD2L1 as a candidate. Hiroaki Matsunami from Duke University Medical Center in Durham, North Carolina, and colleagues showed PKD2L1 and PKD1L3 being activated by acid in mouse cells in the lab dish2. They also found that these proteins were well positioned on the tongue for contact with food, but were unable to confirm that there was just one dedicated receptor for sour taste. Zuker's work fills that gap.

The two studies together certainly seem to point the way to understanding sour taste, says Gary Beauchamp of the Monell Center in Philadelphia, Pennsylvania.

Taste test

But it seems that not everything is understood. Strangely, while taste is an instantaneous perception, Matsunami's work showed a delay between the introduction of acid and the cells firing off a 'sour' signal, says Zuker. This indicates that something else might be going on inside the mouth to help mammals identify the taste.

Beauchamp adds that it is also unclear how or why a sour receptor would come to be. There is a clear evolutionary motivation for the existence of some other taste receptors: bitterness detects poison and sweetness detects sugar, an essential source of energy. "It is still not entirely convincing why we need a sour taste receptor," says Beauchamp. "None of the suggestions for sour taste, such as being able to detect unripe fruits, are entirely compelling."

For Zucker's team, what comes next is a search for the salt receptor. "It's just a case of going through those proteins that are left behind when all the other taste receptors are gone," says Zuker.


Source - Nature

(http://www.nature.com/news/2006/060821/pf/060821-9_pf.html)

Steven
_______________________________________________________________
In a time of universal deceit - telling the truth is a revolutionary act.
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 23/08/2006 15:54:51
" NASA Announces Dark Matter Discovery

Astronomers who used NASA's Chandra X-ray Observatory will host a media teleconference at 1 p.m. EDT Monday,
 Aug. 21, to announce how dark and normal matter have been forced apart in an extraordinarily energetic collision.

Shortly before the start of the briefing, images and graphics about the research will be posted at:
http://chandra.harvard.edu/photo/2006/1e0657/  "

http://www.nasa.gov/home/hqnews/2006/aug/HQ_M06128_dark_matter.html
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 23/08/2006 18:13:33
Robert !!...sorry but I was just about to paste all that is in my clipboard about the very item you have just posted about...

oooh...what to do...my clipboard is brimming with all this text...

Ok..I will paste it..

Thanks Robert...hope you don't mind:



NASA finds direct proof of that dark matter exists
NASA NEWS RELEASE
Posted: August 21, 2006


Dark matter and normal matter have been wrenched apart by the tremendous collision of two large clusters of galaxies. The discovery, using NASA's Chandra X-ray Observatory and other telescopes, gives direct evidence for the existence of dark matter.

"This is the most energetic cosmic event, besides the Big Bang, which we know about," said team member Maxim Markevitch of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass.

These observations provide the strongest evidence yet that most of the matter in the universe is dark. Despite considerable evidence for dark matter, some scientists have proposed alternative theories for gravity where it is stronger on intergalactic scales than predicted by Newton and Einstein, removing the need for dark matter. However, such theories cannot explain the observed effects of this collision.

"A universe that's dominated by dark stuff seems preposterous, so we wanted to test whether there were any basic flaws in our thinking," said Doug Clowe of the University of Arizona at Tucson, and leader of the study. "These results are direct proof that dark matter exists."

In galaxy clusters, the normal matter, like the atoms that make up the stars, planets, and everything on Earth, is primarily in the form of hot gas and stars. The mass of the hot gas between the galaxies is far greater than the mass of the stars in all of the galaxies. This normal matter is bound in the cluster by the gravity of an even greater mass of dark matter. Without dark matter, which is invisible and can only be detected through its gravity, the fast-moving galaxies and the hot gas would quickly fly apart.

The team was granted more than 100 hours on the Chandra telescope to observe the galaxy cluster 1E0657-56. The cluster is also known as the bullet cluster, because it contains a spectacular bullet-shaped cloud of hundred-million-degree gas. The X-ray image shows the bullet shape is due to a wind produced by the high-speed collision of a smaller cluster with a larger one.

In addition to the Chandra observation, the Hubble Space Telescope, the European Southern Observatory's Very Large Telescope and the Magellan optical telescopes were used to determine the location of the mass in the clusters. This was done by measuring the effect of gravitational lensing, where gravity from the clusters distorts light from background galaxies as predicted by Einstein's theory of general relativity.

The hot gas in this collision was slowed by a drag force, similar to air resistance. In contrast, the dark matter was not slowed by the impact, because it does not interact directly with itself or the gas except through gravity. This produced the separation of the dark and normal matter seen in the data. If hot gas was the most massive component in the clusters, as proposed by alternative gravity theories, such a separation would not have been seen. Instead, dark matter is required.

"This is the type of result that future theories will have to take into account," said Sean Carroll, a cosmologist at the University of Chicago, who was not involved with the study. "As we move forward to understand the true nature of dark matter, this new result will be impossible to ignore."

This result also gives scientists more confidence that the Newtonian gravity familiar on Earth and in the solar system also works on the huge scales of galaxy clusters.

"We've closed this loophole about gravity, and we've come closer than ever to seeing this invisible matter," Clowe said.

These results are being published in an upcoming issue of The Astrophysical Journal Letters. NASA's Marshall Space Flight Center, Huntsville, Ala., manages the Chandra program. The Smithsonian Astrophysical Observatory controls science and flight operations from the Chandra X-ray Center, Cambridge, Mass.


SOURCE: SPACELIGHTNOW.COM

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ariel on 23/08/2006 22:37:38
Kangaroo Pill to thin numbers

Wednesday, August 23, 2006; Posted: 9:50 a.m. EDT (13:50 GMT)

A female kangaroo seen recently in suburban Sydney.
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi.a.cnn.net%2Fcnn%2F2006%2FWORLD%2Fasiapcf%2F08%2F23%2Fkangaroo.contraceptive.ap%2Flong.kangaroo.ap.jpg&hash=9bb2f9b9d3a5f44ae694034c0cdedb04)

CANBERRA, Australia (AP) -- Scientists are hoping to develop an oral contraceptive for female kangaroos that will keep pouches empty as they hop around the national capital's grassy fringes.

Government ecologist Don Fletcher said Wednesday the oral contraceptive method promised to be more efficient than existing technology for curbing roo numbers around Canberra such as vasectomies for males and injections for females because the fleet-footed marsupials would not need to be captured.

"Realistically, to deal with wild animals it has to be oral," said Fletcher, who is collaborating with Newcastle University scientists on the research.

"One of the challenges is finding kangaroo ice-cream," he said, referring to a food pellet that grass-munching roos will find irresistible.

Field tests of the contraceptive could be under way in two-to-five years, he said.

Kangaroos are an ever-present road hazard in Canberra, particularly in dry months when thousands bounce in from the surrounding countryside to feed on watered lawns and golf courses.

http://www.cnn.com/2006/WORLD/asiapcf/08/23/kangaroo.contraceptive.ap/index.html

(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi11.photobucket.com%2Falbums%2Fa196%2Fbariel%2Ffsm.jpg&hash=27b1c6663feeeee1f95650d42cca0927) ariel
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ukmicky on 24/08/2006 03:21:33
who responsible for going to wide and taking this page over the edge.

Michael
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Mjhavok on 24/08/2006 15:19:20
How the tongue tastes sour
Receptor found that is triggered by acidic foods.


By Lucy Heady

Researchers have worked out how a mammal's tongue detects sour tastes: it's all down to a single, specialized receptor, they say.

Taste in mammals is classified into sweet, salty, bitter, sour and umami (the taste of monosodium glutamate, commonly found in Chinese takeaways). Until now, only the sweet, bitter and umami taste receptors had been identified, and researchers were unsure whether the other two tastes had specialized receptors for them at all.

The three tastes with known receptors are triggered by large molecules, such as sucrose, that latch on to and are recognized by specialized cells on the tongue. But salty and sour are different in that they are the tastes of very simple ions: hydrogen ions (H+) for acidity and, mainly, sodium ions (Na+) for salt. Some researchers have speculated that many cells in the tongue might be able to pick up these signals, relaying the information in a complex pattern of nerve signals to the brain. "This kind of model is very messy," says Charles Zuker of the Howard Hughes Medical Institute in San Diego.

So Zuker's team — the same lab that pinned down the previous three taste receptors — set out to hunt for a sour taste receptor.

Angela Huang, a graduate student in Zuker's lab, first trawled through the mouse genome to pick out any proteins that exist in cell membranes: proteins that can pick up signals from the outside world and transmit them to nerves. That left about 10,000 candidates.

They screened these by assuming that a taste receptor would only be found in a small number of tissue types (specifically tongue taste cells). That whittled the list down to 900. They then looked for gene patterns known to exist in other taste receptors, leaving a single protein called PKD2L1 as a prime candidate.

To check on the action of PKD2L1, the team created genetically engineered mice that produced a toxin in cells expressing PKD2L1, killing these cells. Probes placed inside the mouse brains then showed that no neural activity was prompted by sour-tasting foods in these mice, they report in Nature1. And their behaviour changed to match: they kept licking sour foods, whereas normal mice would run away from acidic snacks (only humans have a taste for sour foods; other animals avoid them).

Sweet success

Zuker's team also hit upon a surprising fact about the sour receptor: it seems to show up in neurons of the spinal cord. "This is the first time that a taste receptor has been shown to respond to stimuli in another part of the body," says Zuker. This 'taste' sensor might help the body to monitor acidity in the nervous system, he says.

Another group of scientists who were similarly on the trail of a sour-taste receptor also hit upon PKD2L1 as a candidate. Hiroaki Matsunami from Duke University Medical Center in Durham, North Carolina, and colleagues showed PKD2L1 and PKD1L3 being activated by acid in mouse cells in the lab dish2. They also found that these proteins were well positioned on the tongue for contact with food, but were unable to confirm that there was just one dedicated receptor for sour taste. Zuker's work fills that gap.

The two studies together certainly seem to point the way to understanding sour taste, says Gary Beauchamp of the Monell Center in Philadelphia, Pennsylvania.

Taste test

But it seems that not everything is understood. Strangely, while taste is an instantaneous perception, Matsunami's work showed a delay between the introduction of acid and the cells firing off a 'sour' signal, says Zuker. This indicates that something else might be going on inside the mouth to help mammals identify the taste.

Beauchamp adds that it is also unclear how or why a sour receptor would come to be. There is a clear evolutionary motivation for the existence of some other taste receptors: bitterness detects poison and sweetness detects sugar, an essential source of energy. "It is still not entirely convincing why we need a sour taste receptor," says Beauchamp. "None of the suggestions for sour taste, such as being able to detect unripe fruits, are entirely compelling."

For Zucker's team, what comes next is a search for the salt receptor. "It's just a case of going through those proteins that are left behind when all the other taste receptors are gone," says Zuker.


Source - Nature

(http://www.nature.com/news/2006/060821/pf/060821-9_pf.html)

Steven
_______________________________________________________________
In a time of universal deceit - telling the truth is a revolutionary act.
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 25/08/2006 15:25:37
" Ether returns to oust dark matter

From his office window, Glenn Starkman can see the site where Albert Michelson and Edward Morley carried out their famous 1887 experiment that ruled out the presence of an all-pervading "aether" in space, setting the stage for Einstein's special theory of relativity. So it seems ironic that Starkman, who is at Case Western Reserve University in Cleveland, Ohio, is now proposing a theory that would bring ether back into the reckoning. While this would defy Einstein, Starkman's ether would do away with the need for dark matter.

Nineteenth-century physicists believed that just as sound waves move through air, light waves must move through an all-pervading physical substance, which they called luminiferous ("light-bearing") ether. However, the Michelson-Morley experiment failed to find any signs of ether, and 18 years after that, Einstein's special relativity argued that light propagates through a vacuum. The idea of ether was abandoned – but not discarded altogether, it seems.

Starkman and colleagues Tom Zlosnik and Pedro Ferreira of the University of Oxford are now reincarnating the ether in a new form to solve the puzzle of dark matter, the mysterious substance that was proposed to explain why galaxies seem to contain much more mass than can be accounted for by visible matter. They posit an ether that is a field, rather than a substance, and which pervades space-time. "If you removed everything else in the universe, the ether would still be there," says Zlosnik. This ether field isn't to do with light, but rather is something that boosts the gravitational pull of stars and galaxies, making them seem heavier, says Starkman. It does this by increasing the flexibility of space-time itself . "We usually imagine space-time as a rubber sheet that's warped by a massive object," says Starkman. "The ether makes that rubber sheet more bendable in parts, so matter can seem to have a much bigger gravitational effect than you would expect from its weight." The team's calculations show that this ether-induced gravity boost would explain the observed high velocities of stars in galaxies, currently attributed to the presence of dark matter.

This is not the first time that physicists have suggested modifying gravity to do away with this unseen dark matter. The idea was originally proposed by Mordehai Milgrom while at Princeton University in the 1980s. He suggested that the inverse-square law of gravity only applies where the acceleration caused by the field is above a certain threshold, say a0. Below that value, the field dissipates more slowly, explaining the observed extra gravity. "It wasn't really a theory, it was a guess," says cosmologist Sean Carroll at the University of Chicago in Illinois.

Then in 2004 this idea of modified Newtonian dynamics (MOND) was reconciled with general relativity by Jacob Bekenstein at the Hebrew University in Jerusalem, Israel (New Scientist, 22 January 2005, p 10), making MOND a genuine contender in the eyes of some physicists. Bekenstein's work was brilliant, but fiendishly complicated, using many different and arbitrary fields and parameters," says Ferreira. "We felt that something so complicated couldn't be the final theory.

Now Starkman's team has reproduced Bekenstein's results using just one field - the new ether (www.arxiv.org/astro-ph/ 0607411). Even more tantalisingly, the calculations reveal a close relationship between the threshold acceleration a0 - which depends on the ether - and the rate at which the universe's expansion is accelerating. Astronomers have attributed this acceleration to something called dark energy, so in a sense the ether is related to this entity. That they have found this connection is a truly profound thing, says Bekenstein. The team is now investigating how the ether might cause the universe's expansion to speed up.

Andreas Albrecht, a cosmologist at the University of Calfornia, Davis, believes that this ether model is worth investigating further. "We've hit some really profound problems with cosmology Ð with dark matter and dark energy," he says. "That tells us we have to rethink fundamental physics and try something new."

Both Bekenstein and Albrecht say Starkman's team must now carefully check whether the ether theory fits with the motions of planets within our solar system, which are known to a high degree of accuracy, and also explain what exactly this ether is. Ferreira agrees: "The onus is definitely on us to pin this theory down so it doesn't look like yet another fantastical explanation," he says.

However, physicists may be reluctant to resurrect any kind of ether because it contradicts special relativity by forming an absolute frame of reference . "Interestingly, this controversial aspect should make it easy to test for experimentally," says Carroll. "
http://www.eurekalert.org/pub_releases/2006-08/ns-ert082306.php

Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Mjhavok on 25/08/2006 18:50:09
Scientists Make Stem Cells Without Harming Embryos

By using single cells plucked from human embryos, scientists have grown human embryonic stem cells, which can turn into any other kind of cell in the body, while leaving the original embryo intact.

This new technique could potentially allow researchers to generate human embryonic stem cells for therapies and further experiments while avoiding the highly controversial destruction of human embryos required to grow the cells the conventional way.

In addition, the method the scientists used to pluck cells out is already routinely practiced during in vitro fertilization to scan embryos for genetic diseases. This procedure does not harm the embryo's further development.

The researchers at Advanced Cell Technology at Worcester, Mass., coaxed the human embryonic stem cells to become a number of potentially therapeutic cell types. These include blood vessel cells that could help mend hearts after heart attacks, and eye cells "that could help rescue visual function," cell biologist Robert Lanza, Advanced Cell Technology's vice president of research and scientific development, told LiveScience.

With permission, Lanza and his colleagues experimented on 16 unused embryos produced over the course of in vitro fertilization attempts. The researchers used micro-eyedroppers to remove single cells from early-stage embryos, each embryo consisting of only eight to 10 cells.

Using these extracted cells, the scientists generated two stable human embryonic stem cell lineages, capable of replicating for months on end and developing into other cell types.

More research is needed to determine if these new embryonic stem cells behave the same as other human embryonic stem cells, which conventionally are derived from a slightly later stage in embryonic development.

Lanza and his colleagues report their findings online Aug. 23 via the journal Nature.

While these experiments still need to get reproduced by others to show the findings stand up, "this is a good example of solid work," Alberto Hayek at the Whittier Institute for Diabetes in San Diego told LiveScience. He added the main issue now is how similar or different the cells generated by this method are to other human embryonic stem cells researchers have been working with.

SOURCE: http://www.livescience.com

Steven
_______________________________________________________________
In a time of universal deceit - telling the truth is a revolutionary act.
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: elegantlywasted on 28/08/2006 03:23:15
Ahh that crazy Chupacabra is back... or is it? I remember a thread from many moths ago that focused on these guys... thought this article is a bit interesting here goes...

 
quote:
Toronto lab tests mystery 'beast'
25/08/2006 2:18:25 PM  

--------------------------------------------------------------------------------

  Printer-friendly page


Is a mystery beast that frightened Maine residents and preyed on pets a dog-wolf hybrid or something alien?


CBC News
A lab in Toronto is doing DNA tests to try to find out.

For 15 years, residents in Androscoggin County in Maine have reported seeing and hearing an animal with glowing eyes and a chilling cry that was blamed for killing pet dogs.

The animal looked "half rodent, half dog," said Mike O'Donnell, of Turner, Maine, adding it looked like "something out of a Stephen King story."

The roaming creature weighed about 20 kilograms and had a bushy tail, a short snout, short ears and curled fangs hanging over its lips.

Questions remain

When a mysterious animal of similar weight with charcoal-coloured fur, blue eyes and blue lips was apparently hit by a car while chasing a cat two weeks ago, the Sun Journal newspaper in Lewiston, Maine, was inundated with calls from residents wanting to know if it was the same beast.

Loren Coleman, a Portland author and cryptozoologist who studies animals that are rumoured to exist, examined the creature and concluded it was likely a feral dog, but questions lingered.

The newspaper sent a piece of the beast's leg to HealthGene Corp. in Toronto, a laboratory specializing in veterinary DNA testing, for a conclusive answer.

"We are testing for potential DNA in this animal, like dog, wolf, fox, human," Yuri Melekhovets, laboratory director of HealthGen, said with a laugh.

"I don't know, it seems like nobody knows," he told CBC News Online. "So it's a beast."

Hybrid search

Scientists use different probes to identify known DNA, but it's only on TV shows that "aliens" can be tested, Melekhovets said.

"If it's a real beast, we don't have any probes, unfortunately." In that case, it will remain of "unknown origin."

He likened the probes to using night vision goggles to see inside a dark room. Without a probe tool for an animal, the DNA cannot be identified.

For example, dog-wolf hybrids are common, but if the dog is a mix of breeds such as Shar-Pei, German shepherd and Huskie crossed with a wolf, then the results can be "strange," he said.

So far, the lab has extracted DNA. The results are expected next week and will be sent to the Sun Journal.

The findings can suggest whether dog or wolf genes are present, but percentages cannot be determined.

With files from the Associated Press




-Meg
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 31/08/2006 16:13:01
" German researchers find solution to radioactive waste disposal [Date: 2006-08-01]
 
Disposing of nuclear waste presents an enormous challenge for many countries around the world. Some waste, such as that from hospital nuclear medicine departments, contains only small amounts of radioactive materials, which decay in hours or days and so can be treated like ordinary waste.

However, waste with high levels of radioactivity is more problematic as it can take hundreds, if not thousands, of years for the radioactivity to diminish. In that time, sustainable techniques have to be found to isolate this hazardous waste from people and the environment.

German physicists now claim to have the answer to this complex problem. They have come up with a way of speeding up the decay of nuclear waste. The technique involves embedding the waste in metal and cooling it to ultra-low temperatures. Claus Rolfs of Ruhr University in Bochum, Germany, developed the technique after replicating the fusion reactions that take place in the centre of stars. Fusion is the process by which multiple nuclei join together to form a heavier nucleus. It is accompanied by the release or absorption of energy depending on the masses of the nuclei involved.

Using a particle collider, Dr Rolfs fired protons and deuterons (nuclei containing a proton and a neutron) at various light nuclei. He noticed that nuclear fusion occurred at a greater speed when the atomic nuclei were encased in metal and then cooled. This can be explained by the fact that, due to the lower temperature of the metal, the free electrons get closer to the radioactive nuclei. These electrons accelerate positively charged particles towards the nuclei, thereby increasing the probability of fusion reactions.

Given that radioactive decay involves the exact opposite process to that of fusion, Dr Rolfs also fired radioactive nuclei, encased in metal and cooled, into the collider to see whether the free electrons could accelerate the ejection of positively charged particles from a radioactive nucleus. As expected, he observed that radioactive decay occurred and was accelerated considerably by the presence of the lower temperatures and metal casing. According to Dr Rolfs, the technique could potentially cut radioactive material's half-lives - the time it takes for a given radioactive isotope to lose half of its radioactivity - by a factor of 100 or more.

'We are currently investigating radium-226, a hazardous component of spent nuclear fuel with a half-life of 1,600 years. I calculate that using this technique could reduce the half-life to 100 years. At best, I have calculated that it could be reduced to as little as two years. This would avoid the need to bury nuclear waste in deep repositories - a hugely expensive and difficult process,' explains Dr Rolfs.

'The method we are proposing means that nuclear waste could probably be dealt with entirely within the lifetimes of the people that produce it. We would not have to put it underground and let our great-great-grandchildren pay the price for our high standard of living,' he added.

However, further research and testing is needed to fully authenticate the technique. 'We are working on testing the hypothesis with a number of radioactive nuclei at the moment and early results are promising,' he said. 'It is early days, and much engineering research will need to be done to put this idea into practice, but I don't think there will be any insurmountable technical barriers.' "

http://cordis.europa.eu/fetch?CALLER=EN_NEWS&ACTION=D&RCN=26110&DOC=1&CAT=NEWS&QUERY=1157038196026
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 31/08/2006 16:13:01
" German researchers find solution to radioactive waste disposal [Date: 2006-08-01]
 
Disposing of nuclear waste presents an enormous challenge for many countries around the world. Some waste, such as that from hospital nuclear medicine departments, contains only small amounts of radioactive materials, which decay in hours or days and so can be treated like ordinary waste.

However, waste with high levels of radioactivity is more problematic as it can take hundreds, if not thousands, of years for the radioactivity to diminish. In that time, sustainable techniques have to be found to isolate this hazardous waste from people and the environment.

German physicists now claim to have the answer to this complex problem. They have come up with a way of speeding up the decay of nuclear waste. The technique involves embedding the waste in metal and cooling it to ultra-low temperatures. Claus Rolfs of Ruhr University in Bochum, Germany, developed the technique after replicating the fusion reactions that take place in the centre of stars. Fusion is the process by which multiple nuclei join together to form a heavier nucleus. It is accompanied by the release or absorption of energy depending on the masses of the nuclei involved.

Using a particle collider, Dr Rolfs fired protons and deuterons (nuclei containing a proton and a neutron) at various light nuclei. He noticed that nuclear fusion occurred at a greater speed when the atomic nuclei were encased in metal and then cooled. This can be explained by the fact that, due to the lower temperature of the metal, the free electrons get closer to the radioactive nuclei. These electrons accelerate positively charged particles towards the nuclei, thereby increasing the probability of fusion reactions.

Given that radioactive decay involves the exact opposite process to that of fusion, Dr Rolfs also fired radioactive nuclei, encased in metal and cooled, into the collider to see whether the free electrons could accelerate the ejection of positively charged particles from a radioactive nucleus. As expected, he observed that radioactive decay occurred and was accelerated considerably by the presence of the lower temperatures and metal casing. According to Dr Rolfs, the technique could potentially cut radioactive material's half-lives - the time it takes for a given radioactive isotope to lose half of its radioactivity - by a factor of 100 or more.

'We are currently investigating radium-226, a hazardous component of spent nuclear fuel with a half-life of 1,600 years. I calculate that using this technique could reduce the half-life to 100 years. At best, I have calculated that it could be reduced to as little as two years. This would avoid the need to bury nuclear waste in deep repositories - a hugely expensive and difficult process,' explains Dr Rolfs.

'The method we are proposing means that nuclear waste could probably be dealt with entirely within the lifetimes of the people that produce it. We would not have to put it underground and let our great-great-grandchildren pay the price for our high standard of living,' he added.

However, further research and testing is needed to fully authenticate the technique. 'We are working on testing the hypothesis with a number of radioactive nuclei at the moment and early results are promising,' he said. 'It is early days, and much engineering research will need to be done to put this idea into practice, but I don't think there will be any insurmountable technical barriers.' "

http://cordis.europa.eu/fetch?CALLER=EN_NEWS&ACTION=D&RCN=26110&DOC=1&CAT=NEWS&QUERY=1157038196026
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 10/09/2006 00:21:00
ESA steps towards a great black hole census
EUROPEAN SPACE AGENCY NEWS RELEASE
Posted: September 7, 2006

Astronomers using ESA's orbiting gamma-ray observatory, Integral, have taken an important step towards estimating how many black holes there are in the Universe.

An international team, lead by Eugene Churazov and Rashid Sunyaev, Space Research Institute, Moscow, and involving scientists from all groups of the Integral consortium, used the Earth as a giant shield to watch the number of tell-tale gamma rays from the distant Universe dwindle to zero, as our planet blocked their view.

"Point Integral anywhere in space and it will measure gamma rays," says Pietro Ubertini from INAF, Italy, and Principal Investigator on Integral's gamma-ray imager. Most of those gamma rays do not come from nearby sources but from celestial objects so far away that they cannot yet be distinguished as individual sources. This distant gamma-ray emission creates a perpetual glow that bathes the Universe.

Most astronomers believe that the unseen objects are supermassive black holes, millions or billions of times heavier than the Sun and each sitting at the centre of a galaxy. As the black holes swallow matter, the swirling gases release X-rays and gamma rays. Accurately measuring the glow, known as the X-ray and gamma-ray background, is the first step towards calculating how many black holes are contributing to it and how far away in the Universe they are located.

The new Integral observations were made during January and February 2006 and provide highly accurate data on the gamma-ray background. The key to success was using the Earth as a shield.

Allowing the Earth to enter Integral's field of view goes against the standard set of nominal observations for the satellite, because the optical devices needed to determine the spacecraft¹s attitude would be blinded by the bright Earth. So, this operation required remarkable efforts from the ISOC/MOC teams operating the mission, who had to rely on alternative spacecraft control mechanisms. But the risk was worth it: by measuring the decrease of the gamma-ray flux once the Earth had blocked Integral's view and by making a model of the Earth¹s atmospheric emission, the astronomers precisely gauged the gamma-ray background.

Another bonus of the Integral observations is that the observatory's complementary instruments allowed the strength of both X-rays and gamma rays to be measured simultaneously. In the past, different satellites have had to measure the different energies of X-rays and gamma rays, leaving astronomers with the task of having to piece the results together like the pieces of a jigsaw puzzle.

It is not just the overall glow that Integral has seen. Before the satellite's launch, only a few dozen celestial objects were observed in gamma rays. Now Integral sees about 300 individual sources in our Galaxy and around 100 of the brightest supermassive black holes in other galaxies. These are the tip of the iceberg. Astronomers believe there are tens of millions of active black holes spread throughout space, all contributing to the gamma-ray background. From earlier observations in the softer X-ray band it is known that the soft background radiation is almost entirely populated by Active Galactic Nuclei (AGN). So it is highly likely that these objects are also responsible here at higher Integral energies, even if this is not proven yet.

The next step is for astronomers to programme computer models to calculate how the emission from this unseen population of black holes merges to give the observed glow. These computer models will predict the number and distance of the black holes, and provide insights into the way they behave at the centre of young, middle-aged and old galaxies. Meanwhile, the Integral team will continue to refine their measurements of the perplexing gamma-ray background.  


SOURCE:SPACEFLIGHTNOW.COM

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 13/09/2006 15:52:01
" Scandal grows over suspect body parts
 
If you are scheduled for reconstructive orthopaedic surgery, or need a new heart valve, you might want to check where the tissue you are given has come from. For the second time this year, a firm supplying body parts for surgery has been shut down by the US Food and Drug Administration, and more safety scandals are expected to emerge from this booming industry.

The latest scare surrounds Donor Referral Services, based in Raleigh, North Carolina, which harvested body parts, including bone, tendons and heart valves, from corpses in funeral homes. FDA inspectors found numerous safety breaches, including a failure to follow procedures intended to prevent bacterial contamination, and errors in the medical histories of the donors. The FDA is still investigating, and will not comment on how many patients received tainted tissues.

This incident follows a scandal surrounding Biomedical Tissue Services of Fort Lee, New Jersey, which closed in February after similar safety breaches. Company staff were called "bodysnatchers" in media reports, after harvesting tissues from donors without proper consent, and four men now face criminal charges.

Retrieving, processing and distributing body parts is a massive industry, with annual revenues in the US exceeding $1 billion. Yet the safety regulations breached by the two firms did not come into effect until May last year. "We're now peeling the onion and finding where it's rotten," says Areta Kupchyk, a lawyer who helped write the regulations while at the FDA.

The European Union has also started regulating the tissue industry. Since April this year, organisations handling human tissues for use in surgery must be licensed and are subject to inspection. So far, no major problems have emerged with European operators.

The US scandals may have a global reach nonetheless. Australian patients were among those given tissues harvested by Biomedical Tissue Services. Also, Don Keenan, a lawyer in Atlanta, Georgia, is representing patients in Germany and Austria who claim they were infected by other tissues exported from the US.

Keenan's firm has already won damages for American victims of tainted tissues, including the family of Brian Lykins, who died in 2001 from a massive infection of Clostridium bacteria. His knee was rebuilt using cartilage from a corpse left unrefrigerated for at least 19 hours.

The FDA's inspectors face a huge task, as hundreds of organisations in the US handle human tissues for use in surgery. One way forward would be to require them all to be accredited by the American Association of Tissue Banks, which would open them up to additional inspections. Registration takes months, and neither Biomedical Tissue Services nor Donor Referral Services went through this process, which is still voluntary. Similarly, CryoLife of Atlanta, which processed the tissue that killed Lykins, was not accredited at the time.

“The FDA faces a mammoth task to prevent further tragedies: hundreds of organisations in the US handle human tissues”Legislation to force accreditation was introduced into both houses of Congress in April, but observers are not optimistic that it will pass into law. "These are very strong lobbies," says Michele Goodwin, director of the Health Law Institute at DePaul University in Chicago.

From issue 2567 of New Scientist magazine, 31 August 2006, page 10 "
http://www.newscientist.com/article/mg19125674.700-scandal-grows-over-suspect-body-parts.html


Sounds like an episode of "The Sopranos" [:)]
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 15/09/2006 21:08:34
OSLO (Reuters)....Polar bears drown amid Arctic thaw

 Polar bears are drowning and receding Arctic glaciers have uncovered previously unknown islands in a drastic 2006 summer thaw widely blamed on global warming.

Signs of wrenching changes are apparent around the Arctic region due to unusual warmth -- the summer minimum for ice is usually reached between mid-September and early October before the Arctic freeze extends its grip.

"We know about three new islands this year that have been uncovered because the glaciers have retreated," said Rune Bergstrom, environmental adviser to the governor of Svalbard, a Norwegian archipelago about 1,000 km (600 miles) from the North Pole.

The largest is about 300 by 100 metres, he told Reuters.

On a trip this summer "We saw a couple of polar bears in the sea east of Svalbard -- one of them looked to be dead and the other one looked to be exhausted," said Julian Dowdeswell, head of the Scott Polar Research Institute in England.

He said that the bears had apparently been stranded at sea by melting ice. The bears generally live around the fringes of the ice where they find it easiest to hunt seals.

NASA projected this week that Arctic sea ice is likely to recede in 2006 close to a low recorded in 2005 as part of a melting trend in recent decades. A stormy August in 2006 had slightly slowed the 2006 melt.

"There are very unusual conditions this year from Svalbard to Alaska," said Samantha Smith, director of the WWF's environmental group's Arctic Programme.

One international study in 2004 projected that summer ice could disappear completely by 2100, undermining the livelihoods of indigenous peoples and driving creatures such as polar bears towards extinction.

WAKE-UP CALL

Smith said the shrinking ice should be a wake-up call for governments to cut emissions of greenhouse gases, mainly from power plants, factories and cars that most scientists say are causing global warming.

"The Arctic is likely to warm more than any other part of the world" because of global warming, said Dowdeswell. Darker water and soil, once exposed, soaks up far more of the sun's heat than mirror-like ice and snow.

The melt may also open up the Arctic to more exploration for oil, gas and minerals, increase fisheries and open a short-cut shipping route linking the Atlantic and Pacific Oceans.

Ian Stirling, a researcher with the Canadian Wildlife Service, said polar bears were finding it harder to find food, threatening their ability to reproduce.

"In 1980 the average weight of adult females in western Hudson Bay was 650 pounds (300 kg). Their average weight in 2004 was just 507 pounds," he said in a report this week. Numbers in the Hudson Bay region dropped to 950 in 2004 from 1,200 in 1989.

For some, the unseasonal warmth is good news. It was 5 C (41 F) on Friday in Longyearbyen, the main village on Svalbard. "Last year the first snow fell here on September 11 and stayed all winter," said Bergstrom.

"A lot of people here have boats to go out hunting in summer and go to cabins. So it's a good year for them -- the ice melted earlier and they can still use the boats," he said.

Men are the same as women, just inside out !
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 25/09/2006 16:35:16
" Prison calls on dog to sniff out illicit phones

Give the dog a phone: a sniffer dog has been put to work in British prisons with the specific brief of tracking down illicit mobile phones held by inmates.

Murphy, a 15-month-old English springer spaniel, has started work at Norwich Prison in eastern England and will be working at 12 other jails in the region.

Norwich Prison governor James Shanley says their biggest concern is to maintain public protection.

"And we do not want mobile phones to circumvent all the systems set up to provide this," he said.

"If somebody has access to a mobile phone in prison they could potentially contact witnesses, or they could use the phone as a means of escape by arranging for someone to meet them at a certain place.

"Phones can also be used to take photos and could identify staff or other visitors to the prison."

Mr Shanley says about 500 mobile phones have been found in the 12 prisons in the past year.

Murphy, who came from a rescue centre, is believed to be the first mobile phone sniffer dog in Britain's Prison Service. "

http://www.abc.net.au/news/newsitems/200609/s1745690.htm

Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 03/10/2006 16:16:14
" Cloning without stem cells works  

US scientists say stem cells are not necessary for cloning and other cells may even be better candidates.

The Pittsburgh University team created two baby mice from a fully matured blood cell that itself is incapable of making more of its own kind.

It had been thought only immature stem cells, which can become many types of other cell, were capable of doing this.

A UK expert said the Nature Genetics study disproved the idea that only immature cells were of use for cloning.

Alternative routes

Somatic cell nuclear transfer (SCNT) - the scientific term for cloning - is creating an embryo by taking the nucleus, which houses the genetic material of a cell, from one cell and putting it into an unfertilised egg that has had its own genetic material removed.

The resulting embryo is then an exact genetic copy of the cell from the animal or person that donated the nucleus.

 TYPES OF STEM CELLS
Embryonic stem cells - derived from embryos that develop from eggs that have been fertilized
Adult stem cells - immature cells that have yet to fully develop, and found in tissue and organs

Stem cells are still at an early stage of development, and retain the potential to turn into many different types of cell that make up tissues and organs, which is why experts have heralded their promise for treating a variety of genetic diseases.

But experiments using adult stem cells taken from mature tissue to make early stage embryos have yielded disappointing results, with success rates of 1-5%.

Dr Tao Cheng and colleagues tested whether a fully matured type of white blood cell, called a granulocyte, could propagate early embryos.

Not only was this successful, the granulocyte was far better at this than its immature ancestor cells destined to become granulocytes. "

http://news.bbc.co.uk/1/hi/health/5391220.stm
 
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 16/10/2006 17:38:35
" Spider Silk Could Repair Human Ligaments
By Charles Q. Choi
Special to LiveScience
posted: 13 October 2006
10:29 am ET  

Spider web silk, the strongest natural fiber known, could possess untapped medical potential in artificial tendons or for regenerating ligaments, scientists now say.

A body of folklore dating back at least 2,000 years tells of the potential medical value of spider webs in fighting infections, stemming bleeding and healing wounds, explained molecular biologist Randolph Lewis at the University of Wyoming in Laramie. Spider webs have even found a place in Shakespeare's play "A Midsummer Night's Dream," where the character dubbed Bottom noted, "Good Master Cobweb: if I cut my finger, I shall make bold with you."

While research has found no evidence so far that spider webs can kill germs, Lewis explained, studies on animals have revealed that spider silk triggers little if any immune responses, which cause rejection of medical implants.

So his lab and others are spinning spider silks into fibers that they hope might be useful in medicine.

Lewis said researchers at Tufts University in Medford, Mass., have found that spider webs could be used as scaffolds for regenerating ligaments damaged in one of the world's most common knee injuries—ruptured anterior cruciate ligaments, or ACLs. "We're also looking at spider silk in artificial tendons," he said.

Scientists are also developing spider silk to make exceptionally fine sutures for stitching up surgeries or wounds to nerves or eyes, to potentially help them heal without scarring.

"Right now we haven't even optimized the silks we've produced yet, and we're in the ballpark of the material properties you'd want for artificial tendons and ligaments," Lewis told LiveScience.

To mass-produce spider silk, Lewis said "our lab is pursuing the production of spider silk in alfalfa." Other researchers are experimenting with producing spider silk proteins in goat milk. Scientists generate these proteins outside spiders by inserting the genes for them into target cells.

Lewis summed up current work in the latest issue of the journal Chemical Reviews. "

http://www.livescience.com/humanbiology/061013_spider_medicine.html
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 20/10/2006 18:01:16
" Doubt cast on lunar ice deposits  

By Paul Rincon
Science Reporter, BBC News, Wednesday, 18 October 2006.
 
Nasa hopes to return humans to the Moon by 2020
Hopes that the Moon's south pole has significant water ice deposits that could be used to set up a lunar base appear to be unfounded, a study says.

Hypothesised deposits of lunar water-ice have figured in Nasa's planning for future Moon landings.

This resource would be invaluable for supplying bases and making fuel for propelling spacecraft beyond the Moon.

The study in Nature journal suggests radar echoes thought to be from frozen water could be from rocky debris.

The simplest explanation is that we're looking at a signature due to [impact debris] from the crater and not some strange signature due to water ice

Jean-Luc Margot, Cornell University
The first evidence for water-ice deposits came from radar observations made by the US Moon orbiter Clementine, launched in 1994.

According to mission scientists, values for a radar signature called the "circular polarisation ratio (CPR)" indicated frozen water below the dust in craters near the lunar south pole that were shaded from the Sun.

The Clementine researchers also admitted that this radar signature could be created by echoes from rough terrain and walls of impact craters.

In the latest study, Donald Campbell of Cornell University in Ithaca, New York, and colleagues suggest the latter explanation is the more likely. "

http://news.bbc.co.uk/1/hi/sci/tech/6061984.stm
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 27/10/2006 16:02:27
" Stem cell insulin offers hope to type 1 diabetics

28 October 2006

INSULIN-secreting cells have been created from human embryonic stem cells for the first time, raising hopes of a limitless supply of cells that could be transplanted into people with type 1 diabetes.

Emmanuel Baetge and his colleagues at Novocell in San Diego, California, used a cocktail of chemicals to coax the stem cells to form pancreatic cells (Nature Biotechnology, DOI: 10.1038/nbt1259). The cells produce as much insulin as normal pancreatic islet cells, but unlike adult islet cells, this doesn't appear to be regulated by sugar levels. Baetge is confident they can overcome this problem.

If they succeed, the company has also developed a way to coat the cells in a polymer called polyethylene glycol, which would prevent them from being rejected by the recipient's immune system, while allowing sugar, insulin and other signalling molecules to filter in and out. "

http://www.newscientist.com/channel/health/mg19225754.500-stem-cell-insulin-offers-hope-to-type-1-diabetics.html



Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 13/11/2006 16:42:51
Quote

Dolphin May Have 'Remains' of Legs

Possible Evidence Ocean Mammals Lived on Land
In this photo released by Taiji Whale Museum, divers hold a bottlenose dolphin which has an extra set of human palm-sized fins near its tail in Taiji, Wakayama prefecture (state) in western Japan, on Saturday November 4, 2006. Japanese researchers said Sunday that the could be the remains of back legs, providing further evidence that ocean-dwelling mammals once lived on land. (AP Photo/Taiji Whale Museum)

By HIROKO TABUCHI

TOKYO Nov 6, 2006 (AP)— Japanese researchers said Sunday that a bottlenose dolphin captured last month has an extra set of fins that could be the remains of hind legs, a discovery that may provide further evidence that ocean-dwelling mammals once lived on land.

Fishermen captured the four-finned dolphin alive off the coast of Wakayama prefecture (state) in western Japan on Oct. 28, and alerted the nearby Taiji Whaling Museum, according to museum director Katsuki Hayashi.

Fossil remains show dolphins and whales were four-footed land animals about 50 million years ago and share the same common ancestor as hippos and deer. Scientists believe they later transitioned to an aquatic lifestyle and their hind limbs disappeared.

Whale and dolphin fetuses also show signs of hind protrusions but these generally disappear before birth.

Though odd-shaped protrusions have been found near the tails of dolphins and whales captured in the past, researchers say this was the first time one had been found with well-developed, symmetrical fins, Hayashi said.

"I believe the fins may be remains from the time when dolphins' ancient ancestors lived on land … this is an unprecedented discovery," Seiji Osumi, an adviser at Tokyo's Institute of Cetacean Research, said at a news conference televised Sunday.

The second set of fins much smaller than the dolphin's front fins are about the size of human hands and protrude from near the tail on the dolphin's underside. The dolphin measures 8.92 feet and is about five years old, according to the museum.

Hayashi said he could not tell from watching the dolphin swim in a musuem tank whether it used its back fins to maneuver.

A freak mutation may have caused the ancient trait to reassert itself, Osumi said. The dolphin will be kept at the Taiji museum to undergo X-ray and DNA tests, according to Hayashi.

http://abcnews.go.com/Technology/wireStory?id=2629683

"Dolphin with extra fins" sounds like a dish on a Japanese menu  [:)]
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 23/11/2006 21:32:34
'Nymph of the sea' reveals remarkable brood

The scientists discovered the mother complete with her brood of some 20 eggs and 2 possible juveniles inside, together with other details of her soft part anatomy including legs and eyes.

The research team consisted of David Siveter from the University of Leicester, Derek Siveter from Oxford, Mark Sutton from Imperial College London and Derek Briggs from Yale.

The team has made a digital image of the fossil - an ostracod (a relative of the shrimps) - which is preserved exceptionally in volcanic ash rocks in Herefordshire. Their findings are published on line in the Proceedings of the Royal Society.

Professor David Siveter, of the Department of Geology at the University of Leicester, said : "Ostracods are common, pin-head sized crustaceans known from thousands of living species in garden ponds to oceans and from countless fossil shells up to 500 million years old; however, their fossilized soft-parts are exceedingly rare.

"Supposed examples of fossil invertebrate eggs are also few. The fossil we have found contains soft-part anatomy such as legs and eyes and also includes about twenty eggs, each about half a millimetre in size, and two possible juveniles.

"The fossil has been christened Nymphatelina gravida, meaning' a pregnant young woman of the sea'. This remarkable discovery provides an unequivocal and unique view of parental brood care in the invertebrate fossil record, it allows gender to be determined in an animal as old as the Silurian period of geological time, and indicates a remarkably conserved egg brooding reproductive strategy."

SOURCE: EUREKA ALERT
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 23/11/2006 21:36:29
Dad inspired 'Jurassic Park,' son inspires 'Jurassic Poop'
Book reveals how ancient poop has the inside scoop on US past


November 15th, 2006 -- Twenty-five years ago American entomologist George Poinar's work on ancient insects in amber inspired Michael Crichton's futuristic thriller Jurassic Park. Now son Hendrik Poinar's groundbreaking work has inspired the world's first book on the science of fossil feces, Jurassic Poop.

The new children's book by Canadian science writer Jacob Berkowitz reveals that America not only has the world's largest heap of ancient human leavings but that the study of coprolites, or fossil feces, is literally re-writing American history, including who attended the first Thanksgiving.

Developed completely from original scientific sources, Jurassic Poop is the first comprehensive book on coprolites, full of facts and stories that are intriguing to readers five to 100.

"When I saw my first coprolite ten years ago, I thought no way, how could something as soft as poop fossilize?," says Berkowitz. "But coprolites are found on every continent and from every geological time period. There's literally tons of fossil poop out there, and it's now recognized as priceless for helping scientists piece together the puzzle of ancient life."

Jurassic Poop profiles the work of Hendrik Poinar, a professor at McMaster University, in Hamilton, Canada. He was the first ever to extract DNA from ancient feces.

While his father's work in teasing DNA from insects in amber benefited from the revolutionary genetic technological advances of the 1980s -- particularly the invention of the polymerase chain reaction (PCR) to duplicate and thereby identify DNA fragments -- Hendrik's benefited from medical advances. The technique used to extract DNA from coprolites uses a chemical developed for the treatment of diabetes-related complications.

"After being pooh-poohed by scientists for decades, coprolites have now been shown to be the best source of ancient DNA, better than bones and teeth," says Berkowitz. Hendrik Poinar is now able to identify not only a pooper's gender, but also critical genetic information that will help to uncover the very origins of modern humans.

Berkowitz says coprolites even have something to say about one of the seminal stories in American history, the arrival of the Mayflower.

The official Mayflower record says that the only animals on board were two dogs. But in the mid-1990s an archaeological excavation of a 17th century Boston privy revealed another story. The Mayflower was infested with at least 20 types of Old World beetles, stow-aways who quickly called America home -- and do to this day.

Jurassic Poop also reveals that more than 1000 human coprolites have been collected from Hinds Cave in the Chihuahuan desert in southwest Texas, making the site the largest human coprolite cache ever found.

The fossilized specimens were deposited by ancient Americans over the course of about 8000 years. The book notes that these human remains are about 95-per cent fibre. That's about 15 times the amount of fibre the average American eats today. Hendrik Poinar is now collaborating with Vaughn Bryant of Texas A&M University to extract genetic information from the Hinds Cave coprolites.


SOURCE: EUREKA ALERT
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 11/12/2006 23:00:58
Volcanic blast likely killed and preserved juvenile fossil plesiosaur found in Antarctica
Skeleton to be unveiled at US museum December 13


Amid 70-mile-an-hour winds and freezing Antarctic conditions, an American-Argentine research team has recovered the well-preserved fossil skeleton of a juvenile plesiosaur--a marine reptile that swam the waters of the Southern Ocean roughly 70 million years ago.

The fossil remains represent one of the most-complete plesiosaur skeletons ever found and is thought to be the best-articulated fossil skeleton ever recovered from Antarctica. The creature would have inhabited Antarctic waters during a period when the Earth and oceans were far warmer than they are today.

James E. Martin, curator of vertebrate paleontology and coordinator of the paleontology program at the South Dakota School of Mines and Technology's Museum of Geology, announced today the plesiosaur bones will be unveiled at the museum on Dec.13, 2006.

The long-necked, diamond-finned plesiosaurs are probably most familiar as the legendary inhabitants of Scotland's Loch Ness, although scientific evidence indicates the marine carnivores have been extinct for millions of years. But when the creatures were alive, their paddle-like fins would have allowed them to "fly through the water" in a motion very similar to modern-day penguins.

Martin, an expert on fossil marine reptiles, co-led the 2005 expedition to Antarctica that recovered the plesiosaur. Judd Case, of Eastern Washington University, and Marcelo Reguero of the Museo de La Plata, Argentina, were also co- leaders.

The National Science Foundation (NSF) and the Instituto Antártico Argentino, directed by Sergio Marenssi, funded the expedition. The Argentine Air Force provided helicopter support.

NSF manages the U.S Antarctic Program, which coordinates all U.S. research on the southernmost continent. The White House has designated NSF as the lead federal agency for the International Polar Year, a 2-year global research campaign in the polar regions that begins in March 2007.

Preserved by a volcanic blast

After it was prepared in the United States, Martin said, the specimen was discovered tobe the 5-foot-long (1.5 meters) skeleton of a long-necked (elasmosaurid) plesiosaur. An adult specimen could reach over 32 feet (10 meters) in length. Most of the bones of the baby plesiosaur had not developed distinct ends due to the youth of the specimen, he said.

But the animal's stomach area was spectacularly preserved. Stomach ribs (gastralia) span the abdomen, and rather than being long, straight bones like those of most plesiosaurs, these are forked, sometimes into three prongs. Moreover, numerous small, rounded stomach stones (gastroliths) are concentrated within the abdominal cavity, indicating stomach stones were ingested even by juvenile plesiosaurs to help maintain buoyancy or to aid digestion.

The skeleton is nearly perfectly articulated as it would have been in life, but the skull has eroded away from the body. Extreme weather at the excavation site on Vega Island off the Antarctic Peninsula and lack of field time prevented further exploration for the eroded skull.

The researchers speculate volcanism similar to the massive eruption of Mt. St. Helens in Washington in 1980, may have caused the animal's death. Excavation turned up volcanic ash beds layered within the shallow marine sands at the site, and chunks of ash were found with plant material inside. That suggests a major blow-down of trees as was observed when Mt. St. Helens erupted. Either the blast or ash dumped into the ocean, the scientists say, may have caused the baby's demise. Moreover, silica released from the ash allowed spectacular preservation of the skeleton.

High winds, freezing water, hard work

As with the find of a new species of dinosaur Martin and Case made in Antarctica several years ago, the weather and the harsh Antarctic climate made collecting the plesiosaur specimen exceedingly difficult. Weeks of winds exceeding 70 miles an hour hindered the excavation. At the end of the work, icy temperatures turned water to slush before plaster could be mixed to encase the fossil for transportation. The ground was so frozen a digging tool snapped in half during the excavation. Finally, a jackhammer had to be carried up to the site in backpacks along with gasoline, plaster, and water.

The resulting package of plesiosaur remains encased in a protective plaster jacket was too large to carry, so the Argentine air force brought helicopters to the rescue. It took five men to lift the specimen into the chopper, which delivered the cargo to the tent camp on the shores of Herbert Sound. The specimen was later picked up by the Laurence M. Gould, an NSF-chartered research vessel.

At the Museum of Geology, the reptile was prepared by Michelle Pinsdorf and replicated by Shawna Johnson, both master's degree students of paleontology at the South Dakota School of Mines.

A prehistoric nursery

J. Foster Sawyer, of the South Dakota Geological Survey and the School of Mines, found the skeleton while working with Martin at an elevation of 650 feet (200 meters) on Vega Island. Sawyer found vertebrae exposed by wind from the ancient sandy seabed. The bones were embedded in rocks and associated with marine shellfish that suggest the area was a shallow-water marine environment roughly 70 million years ago. Two other partial plesiosaurs were also collected, as well as finds of very advanced shore birds.

Since 1998, expeditions by the American-Argentine team to the area--in part to compare the ancient climates of South Dakota and Antarctica--have secured numerous isolated elements of juvenile plesiosaurs and mosasaurs, a giant marine reptile that looked like an alligator with fins. Martin and his colleagues believe the site may have been a shallow-water area where marine reptiles had their young, and where the young remained until they were of sufficient size and ability to survive in open waters.

Whether plesiosaurs gave live birth has not been proved, but numerous bones and partial skeletons of larger plesiosaurs were found in the same area as the young. Given the long history of plesiosaurs, evolution would have had ample time for them to develop a form of live birth.

The juvenile plesiosaur appears to be related to one discovered in New Zealand in 1874. That plesiosaur was named Mauisaurus and is characterized by a rounded end of the major paddle bone. It was confined to the southern oceans where it existed more than 5 million years.

EUREKAALERT.ORG

Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 11/12/2006 23:17:53
Supercomputer studies Milky Way's halo of dark matter
UC-SANTA CRUZ NEWS RELEASE

Researchers at the University of California, Santa Cruz, have used NASA's most powerful supercomputer to run the largest simulation to date of the formation and evolution of the dark matter halo that envelopes the Milky Way galaxy. Their results show substructures within the halo in unprecedented detail, providing a valuable tool for understanding the evolutionary history of our galaxy.

Every galaxy is surrounded by a halo of mysterious dark matter that can only be detected indirectly by observing its gravitational effects. The invisible halo is much larger and more spherical than the luminous galaxy at its center. Recent computer simulations have shown that the halo is surprisingly clumpy, with relatively dense concentrations of dark matter in gravitationally bound 'subhalos' within the halo. The new study, which has been accepted for publication in the Astrophysical Journal, shows much more extensive substructure than any previous study.

"We find almost 10,000 subhalos, about one order of magnitude more than in any past simulations, and some of our subhalos exhibit 'subsubstructure.' This was expected theoretically, but we have shown it for the first time in a numerical simulation," said Piero Madau, professor of astronomy and astrophysics at UCSC and a coauthor of the paper.

Jurg Diemand, a Hubble postdoctoral fellow at UCSC and first author of the paper, said the new results exacerbate what is known as the "missing satellite problem." The problem is that the clumpiness of the normal matter in and around our galaxy--in the form of dwarf satellite galaxies--does not match the clumpiness of the dark matter seen in the simulation.

"Astronomers keep discovering new dwarf galaxies, but there are still only about 15 or so, compared to about 120 dark matter subhalos of comparable size in our simulation. So which ones host the dwarf galaxies, and why?" Diemand said.

Theoretical models in which star formation is restricted to certain types of dark matter halos--sufficiently massive or early-forming ones--may help to resolve the discrepancy, Madau said.

Although the nature of dark matter remains a mystery, it appears to account for about 82 percent of the matter in the universe. As a result, the evolution of structure in the universe has been driven by the gravitational interactions of dark matter. The "normal" matter that forms gas and stars has fallen into the "gravitational wells" created by clumps of dark matter, giving rise to galaxies in the centers of dark matter halos.

Initially, gravity acted on slight density fluctuations present shortly after the Big Bang to pull together the first clumps of dark matter. These grew into larger and larger clumps through the hierarchical merging of smaller progenitors. This is the process the UCSC researchers simulated on the Columbia supercomputer at the NASA Ames Research Center, one of the fastest computers in the world. The simulation took a couple of months to complete, running on 300 to 400 processors at a time for 320,000 "cpu-hours," Diemand said.

Coauthor Michael Kuhlen, who began working on the project as a graduate student at UCSC and is now at the Institute for Advanced Study in Princeton, said the researchers set the initial conditions based on the most recent results from the Wilkinson Microwave Anisotropy Probe (WMAP) experiment. Released in March, the new WMAP results provide the most detailed picture ever of the infant universe.

The simulation starts at about 50 million years after the Big Bang and calculates the interactions of 234 million particles of dark matter over 13.7 billion years of cosmological time to produce a halo on the same scale as the Milky Way's. The clumps within the halo are the remnants of mergers in which the cores of smaller halos survived as gravitationally bound subhalos orbiting within the larger host system.

The simulation produced five massive subhalos (each more than 30 million times the mass of the Sun) and many smaller ones within the inner 10 percent of the host halo. Yet only one known dwarf galaxy (Sagittarius) is that close to the center of the Milky Way, Diemand said.

"There are big clumps of dark matter in the same region where the disk of the Milky Way would be. So even in the local neighborhood of our solar system, the distribution of dark matter may be more complicated than we have assumed," he said.

Astronomers may be able to detect clumps of dark matter within the Milky Way's halo with future gamma-ray telescopes, but only if the dark matter consists of the types of particles that would give rise to gamma-ray emissions. Certain dark matter candidates--such as the neutralino, a theoretical particle predicted by supersymmetry theory--could annihilate (that is, be mutually destroyed) in collisions, generating new particles and emitting gamma rays.

"Existing gamma-ray telescopes have not detected dark matter annihilation, but upcoming experiments will be more sensitive, so there is some hope that individual subhalos may produce an observable signature," Kuhlen said.

In particular, astronomers look forward to interesting results from the Gamma Ray Large Area Space Telescope (GLAST), scheduled for launch in 2007, he said.

The simulation also provides a useful tool for observational astronomers studying the oldest stars in our galaxy by providing a link between current observations and earlier phases of galaxy formation, Diemand said.

"The first small galaxies formed very early, about 500 million years after the Big Bang, and there are still today stars in our galaxy that formed at this early time, like a fossil record of early star formation. Our simulation can provide the context for where those old stars came from and how they ended up in dwarf galaxies and in certain orbits in the stellar halo today," Diemand said.

SPACEALERTNOW.COM
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 19/12/2006 02:43:58
THIS IS GOING TO BE GREAT..I HOPE !

Nasa and Google reach for the stars

By Chris Nuttall in San Francisco

Published: December 19 2006 01:00 | Last updated: December 19 2006 01:00

Google is extending its reach to the stars in an agreement with Nasa that will allow it to present web visualisations of the US space agency’s data on the universe.

Nasa’s Ames Research Center in Silicon Valley on Monday announced a “Space Act Agreement” with Google that would include collaboration on large-scale data management and massively distributed computing as well as focusing on making the most useful of Nasa’s information available over the internet.

The agreement follows Google’s decision last year to build a 1m square foot campus in a science park linked to the research centre.

There are plans for real-time weather visualisation and forecasting, high-resolution 3-D maps of the moon and Mars and real-time tracking of the International Space Station and the space shuttle.

Google Earth, the software programme that maps the planet, will incorporate Nasa data into future releases.

“This agreement between Nasa and Google will soon allow every American to experience a virtual flight over the surface of the moon or through the canyons of Mars,” said Michael Griffin, Nasa administrator.

Chris Kemp, business development director at Ames, said Nasa had more information on the planet and universe than any other entity in history, but much of it was scattered and difficult to access.

“We are bringing together some of the best research scientists and engineers to form teams to make more of Nasa’s vast information accessible,” he said.

Sergey Brin and Larry Page, Google’s founders, are fascinated with space.

Mr Page is on the board of the X Prize Foundation, which uses competitions to foster breakthroughs in space.

Their Google Maps service includes charts of the moon and they have hired Vint Cerf, who has worked with Nasa on the concept of an interplanetary internet, as their Chief Internet Evangelist.

Copyright The Financial Times Limited 2006
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: WylieE on 20/12/2006 00:17:29
Tripoli Six Sentenced to Die
The Times     December 20, 2006

Gaddafi faces outrage as nurses on mercy mission are sentenced to die
Charles Bremner in Paris
# Six blamed for giving children HIV
# Second trial after seven years in jail

Five nurses who travelled to Libya to care for sick children were facing death by firing squad last night after being found guilty of deliberately infecting 426 young patients with HIV.

Their conviction, after seven years in jail and two trials, prompted an international outcry and raised the stakes for Colonel Muammar Gaddafi as he tries to regain favour with Europe and the US.

Legal appeals are expected to lead to fresh diplomatic negotiations aimed at a face-saving arrangement for the Libyan leader, who faces domestic pressure for vengeance against an alleged foreign plot to infect children with the virus.

The five Bulgarian women wept as Judge Mahmoud Haouissa pronounced the sentences at the end of a trial that was condemned by scientists, Western governments and human rights organisations.

Ashraf Alhajouj, a Palestinian doctor in his late thirties who received the same sentence, sat impassively behind the bars of the dock. “The verdict doesn’t change anything. We are still innocent,” he said.

The court also ordered the Libyan State to pay the families between $250,000 (£127,000) and $900,000 for each victim. The defendants’ lawyer said that they would appeal.

Aids experts and 114 Nobel prizewinners had called for the swift release of the medical workers. However, relatives of the infected children were delighted. Families celebrated by dancing outside the court. “We are happy,” said Subhy Abdullah, whose daughter Mona, 7, died of Aids contracted at al-Fateh Children’s Hospital in Benghazi.

The death of an eight-year-old boy this week brought to 53 the total of deaths in an epidemic that is seen in Benghazi as a plot to kill Muslims.

However, Ali al-Hasnawi, the Justice Minister, said that there could be “a complete revision of the case”, which had already been tried once before and rejected on appeal. Diplomats see the sentences as a prelude to new contacts between Colonel Gaddafi and Western governments who are keen to keep his country within their fold. Last year the European Union opened the way to a compromise over the affair with a Benghazi action plan. This sent European doctors to the Mediterranean city to provide training and advice in setting up an HIV treatment centre. Most of the surviving children are being treated in hospitals in France and Italy at Colonel Gaddafi’s expense.

The six were part of a larger group of volunteers who went to al-Fateh hospital in 1998. In that year 426 children were confirmed as being HIV-positive. The following year, 19 of the foreigners were arrested, but 13 were later released.

In May 2004 the remaining six — Christiana Valcheva, Dr Alhajouj, Snezhana Dimitrova, 54, Alia Cherveniashka, 51, Nasya Nenova, 40 and Valentina Siropoulo, 47 — were sentenced to death by firing squad for “undermining the security of the State”.

The court ignored testimony from Professor Luc Montagnier — the French doctor who was a co-discoverer of HIV — that the virus was active in the hospital before the nurses began their contracts there.

Colonel Gaddafi fomented anti-foreigner feeling, saying that the CIA or the Israeli Mossad had designed a strain of killer virus and given it to the medical staff to experiment on Libyan children. Now the colonel is seen by experts as using the Benghazi Six as a pawn in his discussions over oil, arms and aircraft, and Middle Eastern diplomacy. 

Twists and turns for the Benghazi Six

February 1999 19 Bulgarian health workers arrested on suspicion of spreading HIV

2000 Five Bulgarian nurses and two doctors — one Bulgarian, one Palestinian — go on trial

2001 Court calls for the death sentence

2002 Three of the accused retract confessions, saying they were given under duress

2003 French specialists testify that HIV was caused by poor hygiene

2004 Nurses and Palestinian doctor sentenced to death; Bulgarian doctor sentenced to four years in jail for currency smuggling. Bulgaria rejects Libyan offer to drop the case in exchange for $10 million for each infected child

2005 Ten Libyan officers accused of torturing the health workers acquitted

Source: agencies
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 23/12/2006 01:55:54
Researchers identify a 'heartbeat' in Earth's climate

A few years ago, an international team of researchers went to the middle of the Pacific Ocean and drilled down five kilometers below sea level in an effort to uncover secrets about the earth's climate history. They exceeded their expectations and have published their findings in the Dec. 22 edition of the journal Science.

The researchers' drilling produced pristine samples of marine microfossils, otherwise known as foraminifera. Analysis of the carbonate shells of these microfossils, which are between 23 million to 34 million years-old, has revealed that the Earth's climate and the formation and recession of glaciation events in the Earth's history have corresponded with variations in the earth's natural orbital patterns and carbon cycles.

The researchers were particularly interested in these microfossils because they came from the Oligocene epoch, a time in Earth's history known for falling temperatures.

"The continuity and length of the data series we gathered and analyzed allowed for unprecedented insights into the complex interactions between external climate forcing, the global carbon cycle and ice sheet oscillations," said Dr. Jens Herrle, co-author of the paper and a micropaleontology professor at the University of Alberta.

The authors also show how simple models of the global carbon cycle, coupled to orbital controls of global temperature and biological activity, are able to reproduce the important changes observed after the world entered an "ice-house" state about 34 million years ago.

In the early half of the 20th century, Serbian physicist Milutin Milankovitch first proposed that cyclical variations in the Earth-Sun geometry can alter the Earth's climate and these changes can be discovered in the Earth's geological archives, which is exactly what this research team, consisting of members from the United Kingdom, the U.S. and Canada, has done.

"This research is not only concerned with the climate many millions-of-years-ago. Researching and understanding 'extreme' climate events from the geological past allows us to better tune climate models to understand present and future events, and the response to major perturbations of Earth's climate and the global carbon cycle, Herrle added.

eurekalert.org

Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 30/01/2007 16:48:18
Hubble's main camera stops working
BY WILLIAM HARWOOD
STORY WRITTEN FOR CBS NEWS "SPACE PLACE"
Posted: January 29, 2007

A state-of-the-art camera aboard the Hubble Space Telescope has been knocked out of action by an electrical glitch, curtailing the flow of high-resolution imagery from the aging observatory until new instruments can be installed during a final shuttle servicing mission in 2008.

During that flight, a new camera and spectrograph will be installed, along with six new batteries and a suite of stabilizing gyroscopes that should extend Hubble's scientific life until at least 2013 and possibly longer.

But with the apparent demise of the Advanced Camera for Surveys, installed during the most recent shuttle visit in March 2002, the telescope's most spectacular visible-light images of deep space splendors will be on hold, a disappointment to astronomers around the world.

The camera was engineered to last at lest five years and "we always hope we will meet not only the design lifetime but we'll also get a bonus and that these instruments will live beyond that," Preston Burch, Hubble program manager at NASA's Goddard Space Flight Center in Greenbelt, Md., told reporters today. "So obviously we're disappointed."

Given the complexity of the five-spacewalk servicing mission planned for 2008, NASA is unlikely to add any additional repair work to the astronauts' flight plan.

"If you look at Servicing Mission 4 right now, it's very heavily subscribed," Burch said. "So something would need to come off the repair list (to address the ACS problem) and our preliminary discussions with knowledgeable scientists ... have indicated that's probably not a desirable thing to want to do.

"I wouldn't want to say it's totally impossible if we wanted to put this on a crash basis, but it would require considerable additional effort, time and money to do that. ... At first blush, this doesn't look very attractive."

But Burch said installation of the new Wide Field Camera 3 and the planned repair of a spectrographic instrument already aboard the space telescope will replace and extend the lost capability of the Advanced Camera for Surveys.

In the meantime, engineers are conducting a detailed technical review to make sure the electrical problems that hobbled ACS will not affect the Wide Field Camera 3 or the new Cosmic Origins Spectrograph scheduled for installation in 2008.

For redundancy, the ACS was built with dual power and data systems. On June 30, 2006, an electrical glitch knocked one electrical system, known as Side A, out of action.

The B channel failed Jan. 27, apparently because of an unrelated electrical issue. Pressure sensors detected a presumed puff of smoke when the electrical malfunction occurred and while engineers do not believe the telescope's optical system was contaminated, they do not know exactly what went wrong.

"It's sort of like 'CSI: Greenbelt,'" Burch said in a telephone interview. "We may never know."

Engineers may re-power the A side electronics to permit limited operations with one ACS sensor but this so-called "solar blind" channel is used primarily for low-resolution ultraviolet imaging. Barring a complex orbital repair job, high-resolution visible light pictures will no longer be possible with ACS.

Burch said the B-Side glitch is similar to an electrical problem that earlier affected the Space Telescope Imaging Spectrograph, an instrument shuttle astronauts hope to repair during the 2008 servicing mission.

The similarity in failure modes "is also giving us reason to want to bore into the circuit design and part selection and stuff like that to doubly insure we don't have some kind of latent defect waiting in the wings for COS and WFC-3."

During an earlier review, "we uncovered a lot of workmanship issues ... in the past year and those things have been addressed," Burch said. "It's entirely possible that what just occurred on ACS could very well be a workmanship kind of issue. We don't really know. ... We'll be boring into that very heavily to try to make sure the best we can that the COS and Wide Field 3 are the very best we can make them."

Engineers are hopeful no such problems will be found. With launch now less than two years away, Burch said, "if something like that surfaces, that would be a setback and put a lot of pressure on the program."

Hubble Servicing Mission No. 4 - SM-4 - will be flown aboard the shuttle Atlantis in September 2008. It is the only non-space station mission left on the shuttle manifest, a reflection of the high scientific priority attached to keeping the venerable observatory in operation.

Five back-to-back spacewalks will be required to install six new batteries, six new gyroscopes, the Wide Field Camera 3, the Cosmic Origins Spectrograph and a replacement fine guidance sensor to help the observatory find and track its targets.

The astronauts also will attempt to fix the broken Space Telescope Imaging Spectrograph, a complex task that will require the removal of 111 non-captive screws and the replacement of a power supply circuit board. It is considered the most challenging Hubble repair job since two spacewalking astronauts helped replace a power control unit in 2002.

In addition, Atlantis' crew will install a cooling system to lower the spectrometer's operating temperature, repair degraded thermal insulation and install a fixture that will permit the eventual attachment of a small rocket module to drop it safely out of orbit when it is no longer operational.

The Wide Field Camera 3, installed in place of the current Wide Field Planetary Camera 2, will provide high-resolution optical coverage from the near-infrared region of the spectrum to the ultraviolet.

The Cosmic Origins Spectrograph, sensitive to ultraviolet wavelengths, will take the place of a no-longer-used instrument known as COSTAR that once was used to correct for the spherical aberration of Hubble's primary mirror. All current Hubble instruments are equipped with their own corrective optics

If SM-4 is successful, engineers believe Hubble will remain scientifically productive at least through 2013, an additional five years beyond what could be expected based on the current health of its aging batteries and gyroscopes. With any luck at all, the telescope will still be operating when its replacement, the huge infrared-sensitive James Webb Space Telescope, is launched around 2013.

In the meantime, Hubble's two new science instruments will help the observatory address some of the most fundamental questions in astrophysics and cosmology, including the nature of the so-called dark energy believed to be accelerating the expansion of the universe, and the evolution of galaxies in the wake of the big bang.


Source: Spaceflightnow.org
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 04/02/2007 22:37:53
FSU anthropologist confirms 'Hobbit' indeed a separate species
Dean Falk led international team in brain analysis of ancient hominid

TALLAHASSEE, Fla. -- After the skeletal remains of an 18,000-year-old, Hobbit-sized human were discovered on the Indonesian island of Flores in 2003, some scientists thought that the specimen must have been a pygmy or a microcephalic — a human with an abnormally small skull.

Not so, said Dean Falk, a world-renowned paleoneurologist and chair of Florida State University's anthropology department, who along with an international team of experts created detailed maps of imprints left on the ancient hominid's braincase and concluded that the so-called Hobbit was actually a new species closely related to Homo sapiens.

Now after further study, Falk is absolutely convinced that her team was right and that the species cataloged as LB1, Homo floresiensis, is definitely not a human born with microcephalia — a somewhat rare pathological condition that still occurs today. Usually the result of a double-recessive gene, the condition is characterized by a small head and accompanied by some mental retardation.

"We have answered the people who contend that the Hobbit is a microcephalic," Falk said of her team's study of both normal and microcephalic human brains published in the Jan. 29 issue of the journal PNAS (Proceedings of the National Academy of Sciences of the United States).

The debate stemmed from the fact that archaeologists had found sophisticated tools and evidence of a fire near the remains of the 3-foot-tall adult female with a brain roughly one-third the size of a contemporary human.

"People refused to believe that someone with that small of a brain could make the tools. How could it be a sophisticated new species?"

But that's exactly what it is, according to Falk, whose team had previously created a "virtual endocast" from a three-dimensional computer model of the Hobbit's braincase, which reproduces the surface of the brain including its shape, grooves, vessels and sinuses. The endocasts revealed large parts of the frontal lobe and other anatomical features consistent with higher cognitive processes.

"LB1 has a highly evolved brain," she said. "It didn't get bigger, it got rewired and reorganized, and that's very interesting."

In this latest study, the researchers compared 3-D, computer-generated reconstructions of nine microcephalic modern human brains and 10 normal modern human brains. They found that certain shape features completely separate the two groups and that Hobbit classifies with normal humans rather than microcephalic humans in these features. In other ways, however, Hobbit's brain is unique, which is consistent with its attribution to a new species.

Comparison of two areas in the frontal lobe, the temporal lobe and the back of the brain show the Hobbit brain is nothing like a microcephalic's and is advanced in a way that is different from living humans. In fact, the LB1 brain was the "antithesis" of the microcephalic brain, according to Falk, a finding the researchers hope puts this part of the Hobbit controversy to rest.

It's time to move on to other important questions, Falk said, namely the origin of this species that co-existed at the same time that Homo sapiens was presumed to be the Earth's sole human inhabitant.

"It's the $64,000 question: Where did it come from?" she said. "Who did it descend from, who are its relatives, and what does it say about human evolution? That's the real excitement about this discovery."

###

Falk's co-authors on the PNAS paper, "Brain shape in human microcephalics and Homo floresiensis," are Charles Hildebolt, Kirk Smith and Fred Prior of the Washington University School of Medicine in St. Louis; M.J. Morwood of the University of New England in Australia; Thomas Sutikna, E. Wayhu Saptomo and Jatmiko of the Indonesian Centre for Archaeology in Indonesia; Herwig Imhof of the Medical University of Vienna, Austria; and Horst Seidler of the University of Vienna, Austria.


SOURCE: EUREKALERT.ORG
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 04/02/2007 22:40:37
Physicists find way to 'see' extra dimensions

MADISON - Peering backward in time to an instant after the big bang, physicists at the University of Wisconsin-Madison have devised an approach that may help unlock the hidden shapes of alternate dimensions of the universe.

A new study demonstrates that the shapes of extra dimensions can be "seen" by deciphering their influence on cosmic energy released by the violent birth of the universe 13 billion years ago. The method, published today (Feb. 2) in Physical Review Letters, provides evidence that physicists can use experimental data to discern the nature of these elusive dimensions - the existence of which is a critical but as yet unproven element of string theory, the leading contender for a unified "theory of everything."

Scientists developed string theory, which proposes that everything in the universe is made of tiny, vibrating strings of energy, to encompass the physical principles of all objects from immense galaxies to subatomic particles. Though currently the front-runner to explain the framework of the cosmos, the theory remains, to date, untested.

The mathematics of string theory suggests that the world we know is not complete. In addition to our four familiar dimensions - three-dimensional space and time - string theory predicts the existence of six extra spatial dimensions, "hidden" dimensions curled in tiny geometric shapes at every single point in our universe.

Don't worry if you can't picture a 10-dimensional world. Our minds are accustomed to only three spatial dimensions and lack a frame of reference for the other six, says UW-Madison physicist Gary Shiu, who led the new study. Though scientists use computers to visualize what these six-dimensional geometries could look like (see image), no one really knows for sure what shape they take.

The new Wisconsin work may provide a long-sought foundation for measuring this previously immeasurable aspect of string theory.

According to string theory mathematics, the extra dimensions could adopt any of tens of thousands of possible shapes, each shape theoretically corresponding to its own universe with its own set of physical laws.

For our universe, "Nature picked one - and we want to know what that one looks like," explains Henry Tye, a physicist at Cornell University who was not involved in the new research.

Shiu says the many-dimensional shapes are far too small to see or measure through any usual means of observation, which makes testing this crucial aspect of string theory very difficult. "You can theorize anything, but you have to be able to show it with experiments," he says. "Now the problem is, how do we test it?"

He and graduate student Bret Underwood turned to the sky for inspiration.

Their approach is based on the idea that the six tiny dimensions had their strongest influence on the universe when it itself was a tiny speck of highly compressed matter and energy - that is, in the instant just after the big bang.

"Our idea was to go back in time and see what happened back then," says Shiu. "Of course, we couldn't really go back in time."

Lacking the requisite time machine, they used the next-best thing: a map of cosmic energy released from the big bang. The energy, captured by satellites such as NASA's Wilkinson Microwave Anisotropy Probe (WMAP), has persisted virtually unchanged for the last 13 billion years, making the energy map basically "a snapshot of the baby universe," Shiu says. The WMAP experiment is the successor to NASA's Cosmic Background Explorer (COBE) project, which garnered the 2006 Nobel Prize in physics.

Just as a shadow can give an idea of the shape of an object, the pattern of cosmic energy in the sky can give an indication of the shape of the other six dimensions present, Shiu explains.

To learn how to read telltale signs of the six-dimensional geometry from the cosmic map, they worked backward. Starting with two different types of mathematically simple geometries, called warped throats, they calculated the predicted energy map that would be seen in the universe described by each shape. When they compared the two maps, they found small but significant differences between them.

Their results show that specific patterns of cosmic energy can hold clues to the geometry of the six-dimensional shape - the first type of observable data to demonstrate such promise, says Tye.

Though the current data are not precise enough to compare their findings to our universe, upcoming experiments such as the European Space Agency's Planck satellite should have the sensitivity to detect subtle variations between different geometries, Shiu says.

"Our results with simple, well-understood shapes give proof of concept that the geometry of hidden dimensions can be deciphered from the pattern of cosmic energy," he says. "This provides a rare opportunity in which string theory can be tested."

Technological improvements to capture more detailed cosmic maps should help narrow down the possibilities and may allow scientists to crack the code of the cosmic energy map - and inch closer to identifying the single geometry that fits our universe.

The implications of such a possibility are profound, says Tye. "If this shape can be measured, it would also tell us that string theory is correct."

###

The new work was funded by grants from the National Science Foundation, the U.S. Department of Energy, and the Research Corp.


SOURCE: EUREKALERT.ORG
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ukmicky on 08/02/2007 18:42:03
http://www.newscientist.com/article/dn11140-fatfighting-pill-gains-approval-in-us.html


The first over-the-counter weight-loss pill won approval from US health officials on Wednesday,

 despite health concerns from consumer groups.

The drug orlistat – made by GlaxoSmithKline (GSK) and sold as Alli – reduces the amount of fat the body absorbs from food. It is a half-dose version of a prescription medicine called Xenical, sold by Roche.

The Food and Drug Administration (FDA) approved Alli for use by overweight adults and stressed the drug should be combined with a reduced-calorie, low-fat diet and exercise. "This drug is only going to be effective if used in conjunction with a weight-loss programme," said Charles Ganley, FDA's head of non-prescription drug products.

The drug's packaging will say that for every 5 pounds lost through diet, Alli can help a person drop 2 or 3 pounds more. According to Ganley, studies by GSK found 28% of Alli users lost 5% to 10% of their body weight over six months, compared to about 18% who took a placebo.

Alli works by reducing the amount of the fat that the body absorbs by about one-quarter. The undigested fat is eliminated through bowel movements, which can cause side effects such as gas, diarrhoea and an oily discharge.

Vitamin supplements
Eating a low-fat diet can reduce the side effects, GSK and the FDA said in a statement. Alli users were also advised to take a multivitamin at bedtime to make up for the possible loss of certain nutrients, the FDA added.

Alli is now the only non-prescription weight-loss remedy with FDA approval, although many companies sell over-the-counter supplements that claim weight-loss benefits.

Consumer group Public Citizen, which has urged a ban on prescription Xenical, said Alli should not have been approved because of precancerous colon lesions linked to the drug in animal studies. The group also described the drug's benefits as "marginal."

Alli will cost about $2 a day and be in stores by summer, said GSK’s Steven Burton. Glaxo previously estimated that five to six million Americans would buy Alli over the counter. Burton said the potential market was likely to be larger, but declined to give sales projections.



NewScientist.com news service
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ukmicky on 08/02/2007 18:51:13
Narcolepsy hints at drug for insomniacs


Trouble sleeping? Insomniacs can take heart from a new drug that makes the brain enter a state similar to narcolepsy.

People with narcolepsy suddenly and unexpectedly fall asleep, probably because of defective orexin neurons in the hypothalamus. These normally release proteins called orexins that are needed to keep us awake.

Catherine Brisbare-Roch at Actelion Pharmaceuticals in Allschwil, Switzerland, and her colleagues have developed a drug that blocks orexin receptors, in turn reducing the neurons' firing rate. Preliminary studies suggest that the drug promotes sleepiness in rats, dogs and people (Nature Medicine, DOI: 10.1038/nm1544).

Unlike other sleeping pills, the drug also increases the time spent in REM sleep, when the brain is thought to organise memories, so it may not cause the forgetfulness and memory disruption linked to regular sleeping pill use



From issue 2589 of New Scientist magazine, 06 February 2007
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 08/02/2007 19:27:21
Excellent article..Thanks Michael
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 15/02/2007 03:49:31
LSU professor resolves Einstein's twin paradox

BATON ROUGE – Subhash Kak, Delaune Distinguished Professor of Electrical and Computer Engineering at LSU, recently resolved the twin paradox, known as one of the most enduring puzzles of modern-day physics.

First suggested by Albert Einstein more than 100 years ago, the paradox deals with the effects of time in the context of travel at near the speed of light. Einstein originally used the example of two clocks – one motionless, one in transit. He stated that, due to the laws of physics, clocks being transported near the speed of light would move more slowly than clocks that remained stationary. In more recent times, the paradox has been described using the analogy of twins. If one twin is placed on a space shuttle and travels near the speed of light while the remaining twin remains earthbound, the unmoved twin would have aged dramatically compared to his interstellar sibling, according to the paradox.

“If the twin aboard the spaceship went to the nearest star, which is 4.45 light years away at 86 percent of the speed of light, when he returned, he would have aged 5 years. But the earthbound twin would have aged more than 10 years!” said Kak.

The fact that time slows down on moving objects has been documented and verified over the years through repeated experimentation. But, in the previous scenario, the paradox is that the earthbound twin is the one who would be considered to be in motion – in relation to the sibling – and therefore should be the one aging more slowly. Einstein and other scientists have attempted to resolve this problem before, but none of the formulas they presented proved satisfactory.

Kak’s findings were published online in the International Journal of Theoretical Science, and will appear in the upcoming print version of the publication. “I solved the paradox by incorporating a new principle within the relativity framework that defines motion not in relation to individual objects, such as the two twins with respect to each other, but in relation to distant stars,” said Kak. Using probabilistic relationships, Kak’s solution assumes that the universe has the same general properties no matter where one might be within it.

The implications of this resolution will be widespread, generally enhancing the scientific community’s comprehension of relativity. It may eventually even have some impact on quantum communications and computers, potentially making it possible to design more efficient and reliable communication systems for space applications.

SOURCE: EUREKAALERT.ORG
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 15/02/2007 03:53:08

Scientists elucidate the origin of the darkest galaxies in the universe


Ghostly galaxies composed almost entirely of dark matter speckle the universe. Unlike normal galaxies, these extreme systems contain very few stars and are almost devoid of gas. Most of the luminous matter, so common in most galaxies, has been stripped away, leaving behind a dark matter shadow. These intriguing galaxies-known as dwarf spheroidals-are so faint that, although researchers believe they exist throughout the universe, only those relatively close to Earth have ever been observed. And until recently, no scientific model proposed to unravel their origin could simultaneously explain their exceptional dark matter content and their penchant for existing only in close proximity to much larger galaxies.

Now, Stelios Kazantzidis, a researcher at Stanford University's Kavli Institute for Particle Astrophysics and Cosmology (KIPAC), in collaboration with Lucio Mayer of the Swiss Federal Institute of Technology in Zurich and the University of Zurich, Chiara Mastropietro of the University of Munich in Germany and James Wadsley of McMaster University in Canada, has developed an elegant explanation for how galaxies come to be dominated by dark matter. Kazantzidis, who completed part of the study as a fellow at the University of Chicago's Kavli Institute for Cosmological Physics, reports his findings in the Feb. 15 issue of Nature.

"These results are so exciting because they are based on a combination of physical effects that has never before been postulated," said Kazantzidis. "This is one step toward a more complete understanding of the formation of structure in the universe, which is one of the fundamental goals of astrophysics."

Using supercomputers to create novel simulations of galaxy formation, Kazantzidis and his collaborators found that a dark matter-dominated galaxy begins life as a normal system. But when it approaches a much more massive galaxy, it simultaneously encounters three environmental effects-"ram pressure," "tidal shocking" and the cosmic ultraviolet background-that transform it into a mere dark-matter shadow of its former self.

About 10 billion years ago, when the gas-rich progenitors of dark matter-dominated galaxies originally fell into the Milky Way, the universe was hot with a radiation called the cosmic ultraviolet background. As a small satellite galaxy traveled along its elliptical path around a more massive galaxy, called the host, this radiation made the gas within the smaller galaxy hotter. This state allowed ram pressure-a sort of "wind resistance" a galaxy feels as it speeds along its path-to strip away the gas within the satellite galaxy.

Simultaneously, as the satellite galaxy moved closer to the massive system, it encountered the overwhelming gravitational force of the much larger mass. This force wrenched luminous stars from the small galaxy. Over billions of years of evolution, the satellite passed by the massive galaxy several times as it traversed its orbital path. Each time its stars shook and the satellite lost some of them as a result of a mechanism called tidal shocking. These effects conspired to eventually strip away nearly all the luminous matter-gas and stars-and left behind only a dark-matter shadow of the original galaxy.

The dark matter, on the other hand, was nongaseous and therefore unaffected by the ram pressure force or the cosmic ultraviolet background, the scientists posit. It did experience tidal shocking, but this force alone was not strong enough to pull away a substantial amount of dark matter.

The numerical simulations conducted by Kazantzidis and his collaborators constitute the most extensive calculations ever performed on this topic, consuming up to two months of supercomputing time each at the University of Zurich, the Pittsburgh Supercomputing Center and elsewhere.

"Computer models of galaxy formation in the last decade or so have focused on modeling the properties of dark matter rather than those of the more familiar baryonic [luminous] matter," said co-author Mayer. "Instead, our work suggests that we cannot understand the origin of galaxies without modeling the detailed physics of baryonic matter, even in a dark matter-dominated universe."

The scientists say this new understanding of the origin of the darkest galaxies in the universe may soon lead to fundamental insights into the nature of dark matter.

"Elucidating the nature of dark matter is one of the grandest challenges of modern cosmology," said Kazantzidis. "In the next several years, numerous experiments will attempt to detect dark matter using dwarf spheroidal galaxies as targets." Kazantzidis' work will benefit these studies by offering a better explanation of the origin of ghostly galaxies.

Mystery of the missing satellites

Additionally, the work may help to explain a long-standing discrepancy between theory and observation. The leading modern cosmological model, Lambda Cold Dark Matter ((CDM), predicts that many more small galaxies surround massive galaxies like the Milky Way and Andromeda than are currently observed. This mismatch, which is often referred to as the "missing satellites problem," has been traditionally regarded as one of the toughest challenges to the (CDM paradigm. Kazantzidis' work suggests that the process by which small galaxies are stripped of their luminous matter is common, and implies that the "missing" galaxies could exist in the form of dark matter-dominated satellites.

"These galaxies could just be too dark to detect," he said. "But their possible existence will substantially alleviate the missing satellites problem with profound implications for the predictive power of the (CDM theory." Coincidentally, in the last few months, one of the most advanced observational programs ever undertaken, the Sloan Digital Sky Survey, has revealed in the vicinity of the Milky Way a number of what appear to be ultra-faint satellite galaxies. If this finding is confirmed by follow-up observations and analysis, these newly discovered systems would be explained by Kazantzidis' calculations and would contribute to solving the long-standing missing satellites problem, he says.

SOURCE: EUREKAALERT.ORG
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ROBERT on 01/03/2007 11:09:17
Quote
Chimpanzees 'hunt using spears' 

Chimpanzees in Senegal have been observed making and using wooden spears to hunt other primates, according to a study in the journal Current Biology.
Researchers documented 22 cases of chimps fashioning tools to jab at smaller primates sheltering in cavities of hollow branches or tree trunks.

The report's authors, Jill Pruetz and Paco Bertolani, said the finding could have implications for human evolution. Chimps had not been previously observed hunting other animals with tools.

Pruetz and Bertolani made the discovery at their research site in Fongoli, Senegal, between March 2005 and July 2006.

 

http://news.bbc.co.uk/2/hi/science/nature/6387611.stm

I hope no-one tells Charlton Heston, he may shoot "the filthy apes".   [;D]
http://www.vpc.org/nrainfo/heston.html
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 03/03/2007 04:06:43
Study reveals leaks in Antarctic 'plumbing system'
NASA NEWS RELEASE
Posted: February 24, 2007

WASHINGTON - Scientists using NASA satellites have discovered an extensive network of waterways beneath a fast-moving Antarctic ice stream that provide clues as to how "leaks" in the system impact sea level and the world's largest ice sheet. Antarctica holds about 90 percent of the world's ice and 70 percent of the world's reservoir of fresh water.

With data from NASA satellites, a team of scientists led by research geophysicist Helen Fricker of the Scripps Institution of Oceanography, La Jolla, Calif., detected for the first time the subtle rise and fall of the surface of fast-moving ice streams as the lakes and channels nearly a half-mile of solid ice below filled and emptied. Results were presented at the annual meeting of the American Association for the Advancement of Science (AAAS) in San Francisco. The study was published in the Feb. 16 issue of Science magazine.

"This exciting discovery of large lakes exchanging water under the ice sheet surface has radically altered our view of what is happening at the base of the ice sheet and how ice moves in that environment," said co-author Robert Bindschadler, chief scientist of the Laboratory for Hydrospheric and Biospheric Sciences at NASA's Goddard Space Flight Center, Greenbelt, Md.

"NASA's state-of-the-art satellite instruments are so sensitive we are able to capture an unprecedented three-dimensional look at the system beneath the thick ice sheet and measure from space changes of a mere 3 feet in its surface elevation. That is like seeing an elevation change in the thickness of a paperback book from an airplane flying at 35,000 feet."

The surface of the ice sheet appears stable to the naked eye, but because the base of an ice stream is warmer, water melts from the basal ice to flow, filling the system's "pipes" and lubricating flow of the overlying ice. This web of waterways acts as a vehicle for water to move and change its influence on the ice movement.

Moving back and forth through the system's "pipes" from one lake to another, the water stimulates the speed of the ice stream's flow a few feet per day, contributing to conditions that cause the ice sheet to either grow or decay. Movement in this system can influence sea level and ice melt worldwide.

"There's an urgency to learning more about ice sheets when you note that sea level rises and falls in direct response to changes in that ice," Fricker said. "With this in mind, NASA's ICESat, Aqua and other satellites are providing a vital public service."

In recent years, scientists have discovered more than 145 subglacial lakes, a smaller number of which composes this "plumbing system" in the Antarctic. Bindschadler and Fricker; Ted Scambos of the National Snow and Ice Data Center in Boulder, Colo.; and Laurence Padman of Earth and Space Research in Corvallis, Ore.; observed water discharging from these under-ice lakes into the ocean in coastal areas. Their research has delivered new insight into how much and how frequently these waterways "leak" water and how many connect to the ocean.

The study included observations of a subglacial lake the size of Lake Ontario buried under an active area of west Antarctica that feeds into the Ross Ice Shelf. The research team combined images from the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument aboard NASA's Aqua satellite and data from the Geoscience Laser Altimeter System (GLAS) on NASA's Ice Cloud and Land Elevation Satellite (ICESat) to unveil a multi-dimensional view of changes in the elevation of the icy surface above the lake and surrounding areas during a three-year period. Those changes suggest the lake drained and that its water relocated elsewhere.

MODIS continuously takes measurements of broad-sweeping surface areas at three levels of detail, revealing the outline of under-ice lakes. ICESat's GLAS instrument uses laser altimetry technology to measure even the smallest of elevation changes in the landscape of an ice sheet. Together, data from both have been used to create a multi-year series of calibrated surface reflectance images, resulting in a new technique called satellite image differencing that emphasizes where surface slopes have changed.

Souce: spaceflightnow.com
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 03/03/2007 04:09:55
 
Detection of a colliding-wind beyond the Milky Way

EUROPEAN SPACE AGENCY NEWS RELEASE
Posted: February 25, 2007

Imagine two stars with winds so powerful that they eject an Earth's worth of material roughly once every month. Next, imagine those two winds colliding head-on. Such titanic collisions produce multimillion-degree gas, which radiates brilliantly in X-rays. Astronomers have conclusively identified the X-rays from about two-dozen of these systems in our Milky Way. But they have never seen one outside our galaxy - until now.

Thanks to the European Space Agency's XMM-Newton X-ray observatory, with help from NASA's Chandra X-ray Observatory, an international team led by Dr Yael Naze of the Universite de Liege in Belgium has found such a system in a nearby galaxy. This galaxy, the Small Magellanic Cloud, orbits the Milky Way and is located about 170 000 light-years from Earth.   

The binary system, known as HD 5980, contains two extremely massive stars, 'weighing' about 50 and 30 times the mass of the Sun. Each star radiates more than a million times as much light as the Sun, meaning they put out more light in one minute than our host star generates in an entire year.

The sheer photon pressure of this incredible outpouring of light blows off gas from each star in a supersonic 'wind'. These winds are so powerful that they carry away roughly an Earth mass each month, a rate 10 thousand million times greater than the solar wind, and at a speed 5 times faster than the solar wind itself.

HD 5980's two stars are separated by only about 90 million kilometres, roughly half Earth's average distance from the Sun. "These stars are so close to each other that if they were in our solar system they could fit inside the orbit of Venus," says Naze. As a result, the winds smash into each other with tremendous force, heating the gas and generating enormous numbers of X-rays.

"The system emits about 10 times more energy in X-rays alone than the Sun radiates over the entire spectrum," says team member Dr Michael F. Corcoran, a scientist with the Universities Space Research Association at NASA's Goddard Space Flight Center in Greenbelt, Maryland.

Using data from Chandra, the same team first reported HD 5980's highly energetic X-ray emission in 2002. But its origin was uncertain. Data taken from 2000 to 2005 with XMM-Newton shows that it is indeed produced by a wind collision.

The stars orbit each other every 20 days in a plane that is edge-on to Earth's line of sight, so the stars periodically eclipse each other. The wind collision is thus seen from different angles and through different amounts of material. XMM-Newton saw the X-ray emission rise and fall in a repeatable, predictable pattern.

"Similar X-ray variability from massive binaries inside the Milky Way have been detected, but this is the first indisputable evidence for the phenomenon outside our galaxy," says Naze. "This discovery highlights the great capabilities of modern X-ray observatories."

XMM-Newton has the largest mirrors of any X-ray observatory ever flown, and the sheer size of these mirrors allowed astronomers to monitor this distant system. HD 5980 itself is surrounded by hot interstellar material that creates a diffuse X-ray glow that makes the object difficult to study. "The Chandra data allowed us to pinpoint HD 5980 and resolve the system from the diffuse emission," says Corcoran.

HD 5980 is one of the Small Magellanic Cloud's brightest stars. Situated on the periphery of the star cluster NGC 346, the two stars are nearing the end of their lives and will eventually explode as supernovae. The more massive star, HD 5980A, is passing through a Luminous Blue Variable (LBV) phase - a short-lived, erratic stage that only the most massive stars go through. The most well-known LBV in our galaxy, Eta Carinae, produced a giant outburst that was recorded by astronomers in the 1840s. HD 5980A experienced a smaller-scale outburst that was seen in 1993-94. Its companion, HD 5980B, is an evolved Wolf-Rayet star that has already ejected much of its original envelope.

"It's interesting to be able to study an extragalactic colliding-wind binary like HD 5980 as if it were in our own galaxy", says Corcoran. "Colliding winds provide an important handle on how massive stars shed material. Being able to study them in external galaxies means we can study the effects of different compositions and environments on how these massive stars evolve. From the XMM-Newton data, we can study the delicate balance between the two winds, and determine the changing strength of the winds."

spaceflightnow.com
 
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 03/03/2007 04:13:52
New coating is virtual black hole for reflections

Nonreflecting material may help solar cells catch more of the sun's rays.

Researchers have created an anti-reflective coating that allows light to travel through it, but lets almost none bounce off its surface. At least 10 times more effective than the coating on sunglasses or computer monitors, the material, which is made of silica nanorods, may be used to channel light into solar cells or allow more photons to surge through the surface of a light-emitting diode (LED).

Publishing in the March 1, 2007, Nature Photonics, lead author Jong Kyu Kim and a team from Rensselaer Polytechnic Institute in Troy, N.Y., reveal how they crafted the coating, which reflects almost as little light as do molecules of air.

Guided by National Science Foundation-supported electrical engineer Fred Schubert, the researchers developed a process based on an already common method for depositing layers of silica, the building block of quartz, onto computer chips and other surfaces.

The method grows ranks of nanoscale rods that lie at the same angle. That degree of the angle is determined by temperature. Under a microscope, the films look like tiny slices of shag carpet.

By laying down multiple layers, each at a different angle, the researchers created thin films that are uniquely capable of controlling light. With the right layers in the right configuration, the researchers believe they can even create a film that will reflect no light at all.

One critical application for the material is in the development of next-generation solar cells. By preventing reflections, the coating would allow more light, and more wavelengths of light, to transmit through the protective finish on a solar cell surface and into the cell itself. Engineers may be able to use such a technique to boost the amount of energy a cell can collect, bypassing current efficiency limits.

Another application would involve coating LEDs to eliminate reflections that cut down the amount of light the LED can emit. The researchers hope the efficiency gains could allow the light sources to compete more effectively with fluorescent and incandescent bulbs. So, they will next focus their attention on solid state lighting.


Source: eurekalert.org
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: paul.fr on 08/03/2007 02:25:33
Green light for Australian ban on old-style bulb


Agencies in Canberra and Sydney
Wednesday February 21, 2007
The Guardian

 
Photograph: Guardian
 
Australia is to ban incandescent lightbulbs in an effort to curb greenhouse gas emissions, with the government saying yesterday they would be phased out within three years.
The environment minister, Malcolm Turnbull, said yellow incandescent bulbs, which have been virtually unchanged for 125 years, would be replaced by more efficient compact fluorescent bulbs by 2009. "By that stage you simply won't be able to buy incandescent lightbulbs, because they won't meet the energy standard," he said in a radio interview.

Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 16/03/2007 17:24:14
Paleontologists discover new mammal from Mesozoic Era

Animals shows intermediate ear structure in evolution of modern mammals

An international team of American and Chinese paleontologists has discovered a new species of mammal that lived 125 million years ago during the Mesozoic Era, in what is now the Hebei Province in China.

The new mammal, documented in the March 15 issue of the journal Nature, provides first-hand evidence of early evolution of the mammalian middle ear--one of the most important features for all modern mammals. The discovery was funded by the National Science Foundation (NSF).

"This early mammalian ear from China is a rosetta-stone type of discovery which reinforces the idea that development of complex body parts can be explained by evolution, using exquisitely preserved fossils," said H. Richard Lane, program director in NSF's Division of Earth Sciences, which co-funded the discovery with NSF's Division of Environmental Biology and its Assembling the Tree of Life (AToL) program.

Named Yanoconodon allini after the Yan Mountains in Hebei, the fossil was unearthed in the fossil-rich beds of the Yixian Formation and is the first Mesozoic mammal recovered from Hebei. The fossil site is about 300 kilometers outside of Beijing.

The researchers discovered that the skull of Yanoconodon revealed a middle ear structure that is an intermediate step between those of modern mammals and those of near relatives of mammals, also known as mammaliaforms.

"This new fossil offers a rare insight in the evolutionary origin of the mammalian ear structure," said Zhe-Xi Luo, a paleontologist at the Carnegie Museum of Natural History (CMNH) in Pittsburgh, Pa. "Evolution of the ear is important for understanding the origins of key mammalian adaptations."

Mammals have highly sensitive hearing, far better than the hearing capacity of all other vertebrates, scientists have found. Consequently, paleontologists and evolutionary biologists have been searching for more than a century for clues to the evolutionary origins of mammal ear structure.

Mammalian hearing adaptation is made possible by a sophisticated middle ear of three tiny bones, known as the hammer (malleus), the anvil (incus) and the stirrup (stapes), plus a bony ring for the eardrum (tympanic membrane).

The mammal middle ear bones evolved from the bones of the jaw hinge in their reptilian relatives. However, paleontologists long have attempted to understand the evolutionary pathway via which these precursor jaw bones became separated from the jaw and moved into the middle ear of modern mammals.

"Now we have a definitive piece of evidence, in a beautifully preserved fossil split on two rock slabs," said Luo. "Yanoconodon clearly shows an intermediate condition in the evolutionary process of how modern mammals acquired their middle ear structure."

Yanoconodon is about 5 inches (or 15 cm) long and estimated to weigh about 30 grams. Its teeth are notable for the three cusps in a straight line on molars (thus known as a triconodont) for feeding on insects and worms. It has a long body, short and sprawling limbs and claws that were ideal for either digging or living on the ground.

In addition to its unique ear structure, Yanoconodon also has a surprisingly high number of 26 thoracic ("chest") and lumbar ("waist") vertebrae, unlike most living and extinct terrestrial mammals that commonly have 19 or 20 thoracic and lumbar vertebrae. The extra vertebrae give Yanoconodon a more elongated body form, in contrast to its relatively shorter and very primitive limb and foot structures. The new mammal also has lumbar ribs, a rare feature among modern mammals.

"The discoveries of exquisitely preserved Mesozoic mammals from China have built the evidence such that biologists and paleontologists are able to make sense of how developmental mechanisms have impacted the morphological evolution of the earliest mammals," said Luo.


SOURCE: EUREKALERT
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 16/03/2007 17:25:30
Keeping the body in sync -- the stability of cellular clocks

A study in Switzerland uses the tools of physics to show how our circadian clocks manage to keep accurate time in the noisy cellular environment.

In an article appearing March 13 in the journal Molecular Systems Biology, researchers from the Ecole Polytechnique Federale de Lausanne demonstrate that the stability of cellular oscillators depends on specific biochemical processes, reflecting recent association studies in families affected by advanced sleep phase syndrome.

Circadian rhythms are cyclical changes in physiology, gene expression, and behavior that run on a cycle of approximately one day, even in conditions of constant light or darkness. Peripheral organs in the body have their own cellular clocks that are reset on a daily basis by a central master clock in the brain. The operation of the cellular clocks is controlled by the coordinated action of a limited number of core clock genes. The oscillators work like this: the cell receives a signal from the master pacemaker in the hypothalamus, and then these clock genes respond by setting up concentration gradients that change in a periodic manner. The cell “interprets” these gradients and unleashes tissue-specific circadian responses. Some examples of output from these clocks are the daily rhythmic changes in body temperature, blood pressure, heart rate, concentrations of melatonin and glucocorticoids, urine production, acid secretion in the gastrointestinal tract, and changes in liver metabolism.

In the tiny volume of the cell, however, the chemical environment is constantly fluctuating. How is it possible for all these cell-autonomous clocks to sustain accurate 24-hour rhythms in such a noisy environment?

Using mouse fibroblast circadian bioluminescence recordings from the Schibler Lab at the University of Geneva, the researchers turned to dynamical systems theory and developed a mathematical model that identified the molecular parameters responsible for the stability of the cellular clocks. Stability is a measure of how fast the system reverts to its initial state after being perturbed.

“To my knowledge we are the first to discuss how the stability of the oscillator directly affects bioluminescence recordings,” explains Felix Naef, a systems biology professor at EPFL and the Swiss Institute for Experimental Cancer Research. “We found that the phosphorylation and transcription rates of a specific gene are key determinants of the stability of our internal body clocks.”

This result is consistent with recent research from the University of California, San Francisco involving families whose circadian clocks don’t tick quite right. These families’ clocks are shorter than 24 hours, and they also have mutations in oscillator-related genes. The current results shed light on how a genetically-linked phosphorylation event gone wrong could lead to inaccurate timing of our body clockworks.

SOURCE: EUREKALERT
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 16/03/2007 17:27:34
Robotic telescope unravels mystery of cosmic blasts

Scientists have used the world's largest robotic telescope to make the earliest-ever measurement of the optical polarisation* of a Gamma Ray Burst (GRB) just 203 seconds after the start of the cosmic explosion. This finding, which provides new insight into GRB physics, is published in Science today (15th March 2007).

The scientists from Liverpool John Moores University and colleagues in the UK, Italy, France and Slovenia used the Liverpool Telescope on the island of La Palma and its novel new polarimeter, RINGO, to perform the measurement following detection of the burst by NASA's Swift satellite.

Gamma Ray Bursts are the most instantaneously powerful explosions in the Universe and are identified as brief, intense and completely unpredictable flashes of high energy gamma rays on the sky. They are thought to be produced by the death throes of a massive star and signal the birth of a new black hole or neutron star (magnetar) and ejection of an ultra-high speed jet of plasma. Until now, the composition of the ejected material has remained a mystery and, in particular the importance of magnetic fields has been hotly debated by GRB scientists.

The Liverpool measurement was obtained nearly 100 times faster than any previously published optical polarisation measurement for a GRB afterglow and answers some fundamental questions about the presence of magnetic fields.

Principal author of the Science paper and GRB team leader Dr Carole Mundell of the Astrophysics Research Institute, Liverpool John Moores University, said "Our new measurements, made shortly after the Gamma Ray Burst, show that the level of polarisation in the afterglow is very low. Combined with our knowledge of how the light from this explosion faded, this rules-out the presence of strong magnetic fields in the emitting material flowing out from the explosion - a key element of some theories of GRBs."

The so-called optical afterglow is thought to originate from light emitted when this ejected material impacts the gas surrounding the star. In the first few minutes after the initial burst of gamma rays, the optical light carries important clues to the origin of these catastrophic explosions; capturing this light at the earliest possible opportunity and measuring its properties is ideally suited to the capabilities of large robotic telescopes like the Liverpool Telescope.

Lord Martin Rees, Astronomer Royal and President of the Royal Society said "We are still flummoxed about the underlying 'trigger' for gamma ray bursts, and why they sometimes emit bright flashes of light. Theorists have a lot of tentative ideas, and these observations narrow down the range of options."

Professor Keith Mason, CEO of the Particle Physics and Astronomy Council (PPARC) and UK lead investigator on Swift’s Ultra Violet/Optical Telescope, said, "This result demonstrates well the effectiveness of Swift’s rapid response alert system, allowing robotic telescopes, such as the Liverpool Telescope, to follow up gamma ray bursts within seconds, furthering our knowledge with each detection."

SOURCE: EUREKALERT
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 11/04/2007 03:01:02
A dead star seen snacking on shredded asteroid
SPITZER SCIENCE CENTER NEWS RELEASE


For the last two years, astronomers have suspected that a nearby white dwarf star called GD 362 was "snacking" on a shredded asteroid. Now, an analysis of chemical "crumbs" in the star's atmosphere conducted by NASA's Spitzer Space Telescope has confirmed this suspicion.

"This is a really fascinating system, that could offer clues to what our solar system may look like in approximately five billion years when our Sun becomes a white dwarf," said Dr. Michael Jura, of the University of California at Los Angeles (UCLA).

White dwarfs are essentially the glowing embers of stars that were once like our Sun. Sun-like stars spend most of their lives producing energy by fusing hydrogen atoms into "heavier" helium atoms. Our Sun is currently doing this.

Once the Sun-like star runs out of hydrogen, helium atoms will fuse to produce other heavier elements like carbon, which will eventually sink to the star's core. Meanwhile, the heat released during this helium fusion is so strong that the will star expand and vaporize all dust, rocks and planets that orbit nearby. At this stage, the star is called a "red giant." Ultimately, the red giant will shed its external layers, exposing a dense, hot core about the size of Earth, known as a "white dwarf."

Closely orbiting planets, asteroids, and dust are not expected to survive the red-giant phase of a Sun-like star's life, so astronomers were shocked to find so much dust around the white dwarf GD 362. According to Jura, GD 362 has been a white dwarf for approximately 900 million years -- so surrounding dust should have already been destroyed. He also notes that astronomers were surprised to find chemical elements heavier than hydrogen and helium in GD 362's atmosphere, because these elements should have already sunk to the star's core. When an abundance of heavy elements were first found in GD 362's atmosphere in 2004, scientists were not sure where they came from.

An explanation came in 2005, when two teams of astronomers independently found evidence for dust orbiting GD 362. Both groups argued that the elements in the atmosphere came from orbiting dust particles that rained onto star, and was vaporized by the white dwarf's intense heat. However, astronomers did not know where the dust came from.

Some astronomers predicted that the dust circled the star similar to the way rings of debris orbit Saturn. They believed that the ring of dust around GD 362 came from a large asteroid that had wandered too close to the star, and was shredded by the white dwarf's gravity. Meanwhile, others suspected that dust grains floated into the system from outer space and got pulled into GD 362's atmosphere.

According to Jura, new observations from Spitzer provide direct evidence for the first scenario. He notes that the silicates (sand-like dust grains) in asteroids are very different from the silicates randomly floating around the universe. Using Spitzer's infrared spectrograph instrument, Jura's team determined that the silicates in GD 362's atmosphere resembled the sand-like grains found in asteroids.

With Spitzer's Multiband Imaging Photometer (MIPS) instrument, Jura's team also noticed that the dust disk surrounding GD 362 was confined, meaning they saw an end to the dust disk.

"If this dust was floating in from the interstellar medium [or outer space] and falling onto the star, then we would see a trail of dust leading beyond this star system -- the dust disk shouldn't end. In the Spitzer observations, we see that the dust is confined to a region close to the star," said Jura.

Jura's paper on this topic was has been accepted by the Astronomical Journal. Other authors of this work include Dr. Jay Farihi, of the Gemini Observatory, Hawaii; and Drs. Ben Zuckerman and Eric Becklin, also of UCLA. Becklin led the Gemini North observations that first discovered dust in GD 362's atmosphere.

Source: spaceflightnow.com
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 11/04/2007 03:08:47
Star burps, then explodes
UNIVERSITY OF CALIFORNIA-BERKELEY NEWS RELEASE

BERKELEY - Tens of millions of years ago, in a galaxy far, far away, a massive star suffered a nasty double whammy.

Signs of the first shock reached Earth on Oct. 20, 2004, when the star was observed letting loose an outburst so enormous and bright that Japanese amateur astronomer Koichi Itagaki initially mistook it for a supernova. The star survived for nearly two years, however, until on Oct. 11, 2006, professional and amateur astronomers witnessed it blowing itself to smithereens as Supernova (SN) 2006jc.

"We have never observed a stellar outburst and then later seen the star explode," said University of California, Berkeley, astronomer Ryan Foley. His group studied the 2006 event with ground-based telescopes, including the 10-meter (32.8-foot) W. M. Keck telescopes in Hawaii. Narrow helium spectral lines showed that the supernova's blast wave ran into a slow-moving shell of material, presumably the progenitor's outer layers that were ejected just two years earlier. If the spectral lines had been caused by the supernova's fast-moving blast wave, the lines would have been much broader.

Another group, led by Stefan Immler of NASA's Goddard Space Flight Center in Greenbelt, Md., monitored SN 2006jc with NASA's Swift satellite and the Chandra X-ray Observatory. By observing how the supernova brightened in X-rays, a result of the blast wave slamming into the outburst ejecta, they could measure the amount of gas blown off in the 2004 outburst: about 0.01 solar mass, the equivalent of about 10 Jupiters.

"The beautiful aspect of our SN 2006jc observations is that although they were obtained in different parts of the electromagnetic spectrum, in the optical and in X-rays, they lead to the same conclusions," said Immler.

"This event was a complete surprise," added Alex Filippenko, leader of the UC Berkeley/Keck supernova group and a member of NASA's Swift satellite team. "It opens up a fascinating new window on how some kinds of stars die."

All the observations suggest that the supernova's blast wave took only a few weeks to reach the shell of material ejected two years earlier, which did not have time to drift very far from the star. As the wave smashed into the ejecta, it heated the gas to millions of degrees, hot enough to emit copious X-rays. The Swift satellite saw the supernova continue to brighten in X-rays for 100 days, something that has never been seen before in a supernova. All supernovae previously observed in X-rays have started off bright and then quickly faded to invisibility.

"You don't need a lot of mass in the ejecta to produce a lot of X-rays," noted Immler. Swift's ability to monitor the supernova's X-ray rise and decline over six months was crucial to the mass determination by Immler's team. But he added that Chandra's sharp resolution enabled his group to resolve the supernova from a bright X-ray source that appears in the field of view of Swift's X-ray telescope.

"We could not have made this measurement without Chandra," said Immler, who will submit his team's paper next week to the Astrophysical Journal. "The synergy between Swift's fast response and its ability to observe a supernova every day for a long period, and Chandra's high spatial resolution, is leading to a lot of interesting results."

Foley and his colleagues, whose paper appears in the March 10 Astrophysical Journal Letters, propose that the star recently transitioned from a Luminous Blue Variable (LBV) star to a Wolf-Rayet star. An LBV is a massive star in a brief but unstable phase of stellar evolution. Similar to the 2004 eruption, LBVs are prone to blow off large amounts of mass in outbursts so extreme that they are frequently mistaken for supernovae, events dubbed "supernova impostors." Wolf-Rayet stars are hot, highly evolved stars that have shed their outer envelopes.

Most astronomers did not expect that a massive star would explode so soon after a major outburst, or that a Wolf-Rayet star would produce such a luminous eruption, so SN 2006jc represents a puzzle for theorists.

"It challenges some aspects of our current model of stellar evolution," said Foley. "We really don't know what caused this star to have such a large eruption so soon before it went supernova."

"SN 2006jc provides us with an important clue that LBV-style eruptions may be related to the deaths of massive stars, perhaps more closely than we used to think," added coauthor and UC Berkeley astronomer Nathan Smith. "The fact that we have no well-established theory for what actually causes these outbursts is the elephant in the living room that nobody is talking about."

SN 2006jc occurred in galaxy UGC 4904, located 77 million light years from Earth in the constellation Lynx. The supernova explosion, a peculiar variant of a Type Ib, was first sighted by Itagaki, American amateur astronomer Tim Puckett and Italian amateur astronomer Roberto Gorelli.

SOURCE:SPACEFLIGHTNOW.COM
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 13/04/2007 20:43:25
Ancient T. rex and mastodon protein fragments discovered, sequenced
68-million-year-old T. rex proteins are oldest ever sequenced

Scientists have confirmed the existence of protein in soft tissue recovered from the fossil bones of a 68 million-year-old Tyrannosaurus rex (T. rex) and a half-million-year-old mastodon.

Their results may change the way people think about fossil preservation and present a new method for studying diseases in which identification of proteins is important, such as cancer.

When an animal dies, protein immediately begins to degrade and, in the case of fossils, is slowly replaced by mineral. This substitution process was thought to be complete by 1 million years. Researchers at North Carolina State University (NCSU) and Harvard Medical School now know otherwise.

The researchers' findings appear as companion papers in this week's issue of the journal Science.

"Not only was protein detectably present in these fossils, the preserved material was in good enough condition that it could be identified," said Paul Filmer, program director in the National Science Foundation (NSF) Division of Earth Sciences, which funded the research. "We now know much more about what conditions proteins can survive in. It turns out that some proteins can survive for very long time periods, far longer than anyone predicted."

Mary Schweitzer of NCSU and the North Carolina Museum of Natural Sciences discovered soft tissue in the leg bone of a T. rex and other fossils recovered from the Hell Creek sediment formation in Montana.

After her chemical and molecular analyses of the tissue indicated that original protein fragments might be preserved, she turned to colleagues John Asara and Lewis Cantley of Harvard Medical School, to see if they could confirm her suspicions by finding the amino acid used to make collagen, a fibrous protein found in bone.

Bone is a composite material, consisting of both protein and mineral. In modern bones, when minerals are removed, a collagen matrix--fibrous, resilient material that gives the bones structure and flexibility--is left behind. When Schweitzer demineralized the T. rex bone, she was surprised to find such a matrix, because current theories of fossilization held that no original organic material could survive that long.

"This information will help us learn more about evolutionary relationships, about how preservation happens, and about how molecules degrade over time, which could have important applications in medicine," Schweitzer said.

To see if the material had characteristics indicating the presence of collagen, which is plentiful, durable and has been recovered from other fossil materials, the scientists examined the resulting soft tissue with electron microscopy and atomic force microscopy. They then tested it against various antibodies that are known to react with collagen. Identifying collagen would indicate that it is original to T. rex--that the tissue contains remnants of the molecules produced by the dinosaur.

"This is the breakthrough that says it's possible to get sequences beyond 1 million years," said Cantley. "At 68 million years, it's still possible."

Asara and Cantley successfully sequenced portions of the dinosaur and mastodon proteins, identifying the amino acids and confirming that the material was collagen. When they compared the collagen sequences to a database that contains existing sequences from modern species, they found that the T. rex sequence had similarities to those of chickens, and that the mastodon was more closely related to mammals, including the African elephant.

The protein fragments in the T. rex fossil appear to most closely match amino acid sequences found in collagen of present-day chickens, lending support to the idea that birds and dinosaurs are evolutionarily related.

"Most people believe that birds evolved from dinosaurs, but that's based on the 'architecture' of the bones," Asara said. "This finding allows us the ability to say that they really are related because their sequences are related."

"Scientists had long assumed that the material in fossil bones would not be preserved after millions of years of burial," said Enriqueta Barrera, program director in NSF's Division of Earth Sciences. "This discovery has implications for the study of similarly well-preserved fossil material."

SOURCE: Eurekalert.org
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 13/04/2007 20:57:30
3.2 Billion-Year-Old Surprise: Earth Had Strong Magnetic Field

Geophysicists at the University of Rochester announce in today's issue of Nature that the Earth's magnetic field was nearly as strong 3.2 billion years ago as it is today.

The findings, which are contrary to previous studies, suggest that even in its earliest stages the Earth was already well protected from the solar wind, which can strip away a planet's atmosphere and bathe its surface in lethal radiation.

"The intensity of the ancient magnetic field was very similar to today's intensity," says John Tarduno, professor of geophysics in the Department of Earth and Environmental Sciences at the University of Rochester. "These values suggest the field was surprisingly strong and robust. It's interesting because it could mean the Earth already had a solid iron inner core 3.2 billion years ago, which is at the very limit of what theoretical models of the Earth's formation could predict."

Geophysicists point to Mars as an example of a planet that likely lost its magnetosphere early in its history, letting the bombardment of radiation from the sun slowly erode its early atmosphere. Theories of Earth's field say it's generated by the convection of our liquid iron core, but scientists have always been curious to know when Earth's solid inner core formed because this process provides an important energy source to power the magnetic field. Scientists are also interested in when Earth's protective magnetic cocoon formed.

But uncovering the intensity of a field 3.2 billion years in the past has proven daunting, and until Tarduno's research, the only data scientists could tease from the rocks suggested the field was perhaps only a tenth as strong as today's.

Tarduno had previously shown that as far back as 2.5 billion years ago, the field was just as intense as it is today, but pushing back another 700 million years in time meant he had to find a way to overcome some special challenges.

The traditional approach to measuring the ancient Earth's magnetic field would not be good enough. The technique was developed more than four decades ago, and has changed little. With the old method, an igneous rock about an inch across is heated and cooled in a chamber that is shielded from magnetic interference. The magnetism is essentially drained from the particles in the rock and then it's refilled while scientists measure how much the particles can hold.

Tarduno, however, isolates choice, individual crystals from a rock, heats them with a laser, and measures their magnetic intensity with a super-sensitive detector called a SQUID—a Superconducting Quantum Interface Device normally used in computing chip design because it's extremely sensitive to the tiniest magnetic fields.

Certain rocks contain tiny crystals like feldspar and quartz—nano-meter sized magnetic inclusions that lock in a record of the Earth's magnetic field as they cool from molten magma to hard rock. Simply finding rocks of this age is difficult enough, but these rocks have also witnessed billions of years of geological activity that could have reheated them and possibly changed their initial magnetic record.

To reduce the chance of this contamination, Tarduno picked out the best preserved grains of feldspar and quartz out of 3.2 billion-year-old granite outcroppings in South Africa. Feldspar and quartz are good preservers of the paleomagnetic record because their minute magnetic inclusions essentially take a snapshot of the field as they cool from a molten state. Tarduno wanted to measure the smallest magnetic inclusions because larger magnetic crystals can lose their original magnetic signature at much lower temperatures, meaning they are more likely to suffer magnetic contamination from later warming geological events.

Once he isolated the ideal crystals, Tarduno employed a carbon dioxide laser to heat individual crystals much more quickly than older methods, further lessening the chance of contamination. With the University's ultra-sensitive SQUID he could measure how much magnetism these individual particles contained.

"The data suggest that the ancient magnetic field strength was at least 50 percent of the present-day field, which typically measures 40 to 60 microteslas," says Tarduno. "This means that a magnetosphere was definitely present, sheltering the Earth 3.2 billion years ago."

To further ensure his readings were accurate, Tarduno also checked the alignment of the magnetism in the particles, which record the polarity of the Earth's field at that time and location. By comparing the polarity to that of other samples of similar age and location, Tarduno could ensure that his measurements were not likely from later geological heating, but truly from 3.2 billion years ago.

Tarduno is now pushing back in time to 3.5 billion-year-old rocks to further investigate when the Earth's inner core first formed, giving new insights into early Earth processes that also may have had an effect on the atmosphere and the development of life on the planet.

Rory Cottrell, research scientist in Tarduno's laboratory, is co-author on the study. This research was funded by the National Science Foundation.

Source: University of Rochester News
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 24/04/2007 22:02:57
XMM-Newton pinpoints intergalactic polluters
EUROPEAN SPACE AGENCY NEWS RELEASE
Posted: April 24, 2007

Warm gas escaping from the clutches of enormous black holes could be the key to a form of intergalactic 'pollution' that made life possible, according to new results from ESA's XMM-Newton space observatory.

Black holes are not quite the all-consuming monsters depicted in popular culture.

Until gas crosses the boundary of the black hole known as the Event Horizon, it can escape if heated sufficiently. For decades now, astronomers have watched warm gas from the mightiest black holes flowing away at speeds of 1000-2000 km/s and wondered just how much gas escapes this way. XMM-Newton has now made the most accurate measurements yet of the process.

The international team of astronomers, led by Yair Krongold, Instituto de Astronomia, Universidad Nacional Autonoma de Mexico, targeted a black hole two million times more massive than the Sun at the centre of the active galaxy NGC 4051.

Previous observations had only revealed the average properties of the escaping gas. XMM-Newton has the special ability to watch a single celestial object with several instruments at the same time. With this, the team collected more detailed information about variations in the gas' brightness and ionization state.

The team also saw that the gas was escaping from much closer to the black hole than previously thought. They could determine the fraction of gas that was escaping. "We calculate that between 2-5 percent of the accreting material is flowing back out," says team member Fabrizio Nicastro, Harvard-Smithsonian Centre for Astrophysics. This was less than some astronomers had expected.

The same heating process that allows the gas to escape also rips electrons from their atomic nuclei, leaving them ionised. The extent to which this has happened in an atom is known as its ionisation state. In particular, metals always have positive ionisation states.

The warm gas contains chemical elements heavier than Hydrogen and Helium. Astronomers term them 'metals' since they are elements in which electrons are ripped away and they have positive ionisation states - like metals. They include carbon, the essential element for life on Earth. These metals can only be made inside stars, yet they pollute vast tracts of space between galaxies. Astronomers have long wondered how they arrived in intergalactic space.

This new study provides a clue. More powerful active galaxies than NGC 4051, known as quasars, populate space. They are galaxies in which the central black hole is feeding voraciously. This would mean that quasars must have escaping gas that could carry metals all the way into intergalactic space.

If quasars are responsible for spraying metals into intergalactic space, the pollution would more likely be found in bubbles surrounding each quasar. So, different parts of the Universe would be enriched with metals at different speeds. This may explain why astronomers see differing quantities of metals depending upon the direction in which they look.

However, if the fraction of escaping gas is really as low as XMM-Newton shows in NGC 4051, astronomers need to find another source of intergalactic metals. This might be the more prevalent star-forming galaxies called Ultra Luminous Infra Red Galaxies.

"Based on this one measurement, quasars can contribute some but not all of the metals to the intergalactic medium," says Krongold.

To continue the investigation, the astronomers will have to use the same XMM-Newton technique on a more powerful active galaxy. Such observations will allow them to determine whether the fraction of gas escaping changes or stays the same. If the fraction goes up, they will have solved the puzzle. If it stays the same, the search will have to continue.

The above results have been taken from the study 'The Compact, Conical, Accretion-Disk Warm Absorber of the Seyfert 1 Galaxy NGC 4051 and its Implications for IGM-Galaxy Feedback Processes' by Yair Krongold et al. Published 20 April, in the Astrophysical Journal.

SOURCE: SPACEFLIGHTNOW.COM
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 25/04/2007 15:14:05
Major Discovery: New Planet Could Harbor Water and Life
By Ker Than
Staff Writer
posted: 24 April 2007


An Earth-like planet spotted outside our solar system is the first found that could support liquid water and harbor life, scientists announced today.

Liquid water is a key ingredient for life as we know it. The newfound planet is located at the "Goldilocks" distance—not too close and not too far from its star to keep water on its surface from freezing or vaporizing away.

And while astronomers are not yet able to look for signs of biology on the planet, the discovery is a milestone in planet detection and the search for extraterrestrial life, one with the potential to profoundly change our outlook on the universe.

”The goal is to find life on a planet like the Earth around a star like the Sun. This is a step in that direction,” said study leader Stephane Udry of the Geneva Observatory in Switzerland. “Each time you go one step forward you are very happy.”

The new planet is about 50 percent bigger than Earth and about five times more massive. The new “super-Earth” is called Gliese 581 C, after its star, Gliese 581, a diminutive red dwarf star located 20.5 light-years away that is about one-third as massive as the Sun.

SOURCE: SPACE.COM
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 01/05/2007 20:42:56
Japan's asteroid explorer begins voyage back to Earth
BY STEPHEN CLARK
SPACEFLIGHT NOW
Posted: April 25, 2007

A small Japanese asteroid probe riddled by a streak of bad luck began its slow limp home Wednesday, but officials still face a myriad of challenges to bring the craft back in 2010.

Controllers sent commands for the Hayabusa probe to start one of its four ion engines Wednesday, officially beginning its three-year journey to Earth.

The milestone came after months of tests to determine whether the 900-pound spacecraft was healthy enough to attempt the voyage. Hayabusa is running on a damaged battery and just one of its four ion engines is currently deemed ready for long-term operations, according to the Japanese Aerospace Exploration Agency, or JAXA.

Hayabusa also lost two of its three fast-spinning reaction wheels responsible for attitude control. After the failures, the craft was forced to exhaust all of its chemical propellant reserves.

Engineers devised a new attitude control scheme using excess xenon fuel used by Hayabusa's electric propulsion system. Officials estimate Hayabusa's tanks still hold more than 66 pounds of xenon, while only about 44 pounds are needed for the Earth-bound leg of its mission.

JAXA officials remain cautious about the chances of Hayabusa successfully reaching Earth.

"This is not an optimistic operation, but a very tough operation," said Junichiro Kawaguchi, Hayabusa project manager, in a February interview. "The spacecraft is not in a very healthy state."

The probe is still located in the vicinity of asteroid Itokawa, a small potato-shaped space rock that was the subject of three months of scientific scrutiny by Hayabusa in 2005. Ground teams believe the spacecraft is currently about 50 million miles from Earth.

Hayabusa will have to complete two more orbits around the Sun before reaching Earth in June 2010, when it is expected to separate its return capsule for a parachuted landing in southern Australia.

The reentry vehicle was designed to house small chunks of Itokawa retrieved as Hayabusa swooped down to the surface of the asteroid. A small pellet was to fire into the asteroid to force dust and rocks into the sample chamber, but reviews of data streaming back from the spacecraft later caused engineers to question whether the system worked as planned.

Officials will likely not know for sure if the capsule contains any samples until it lands.

The start of the return trip was postponed by a year after a fuel leak in December 2005 threw Hayabusa off course and cut off communications with the probe for six weeks.

On Tuesday, JAXA released a heap of catalogued raw science data from Hayabusa's mission. The data included more than 1,600 optical images, about 135,000 pieces of spectral data in the near-infrared and X-ray bands, and 1.7 million data points from a laser rangefinder.

Scientists also assembled a three-dimensional shape video of Itokawa, which is believed to have been formed by the collection of several smaller bodies linked together by loose material and weak gravity.

SOURCE: SPACEFLIGHTNOW.COM
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 01/05/2007 20:53:48
Scientists discover vast intergalactic cloud of plasma
LOS ALAMOS NATIONAL LABORATORY NEWS RELEASE
Posted: April 30, 2007

LOS ALAMOS, New Mexico - Combining the world's largest radio telescope at Arecibo, Puerto Rico with a precision imaging, seven-antenna synthesis radio telescope at the Dominion Radio Astrophysical Observatory (DRAO), a team of researchers led by Los Alamos scientist Philipp Kronberg have discovered a new giant in the heavens, a giant in the form of a previously undetected cloud of intergalactic plasma that stretches more than 6 million light years across. The diffuse, magnetized intergalactic zone of high energy electrons may be evidence for galaxy-sized black holes as sources for the mysterious cosmic rays that continuously zip though the Universe. 

In research reported in the April issue of Astrophysical Journal, the team of researchers from Los Alamos, Arecibo, and DRAO in Penticton, British Columbia describe their discovery of a 2-3 megaparsec zone of diffuse, intergalactic plasma located beside the Coma cluster of galaxies. The combined use of the 305 meter Arecibo radio telescope to make a base scan of 50 square degrees of sky, and the DRAO, making 24 separate 12 hour observations over 24 days of the same sky area, resulted in an image comparable to that of a 1000 meter diameter radio telescope. After Arecibo mapped the larger cloud structure, DRAO data was used to enhance the resolution of the image. 

According to Kronberg, "One of the most exciting aspects of the discovery is the new questions it poses. For example, what kind of mechanism could create a cloud of such enormous dimensions that does not coincide with any single galaxy, or galaxy cluster? Is that same mechanism connected to the mysterious source of the ultra high energy cosmic rays that come from beyond our galaxy? And separately, could the newly discovered fluctuating radio glow be related to unwanted foregrounds of the Cosmic Microwave Background (CMB) radiation?" 

The synchrotron-radiating plasma cloud is spread across a vast region of space that may contain several black hole harboring radio galaxies. The cloud may be evidence that black holes in galaxies convert and transfer their enormous gravitational energy, by a yet unknown process, into magnetic fields and cosmic rays in the vast intergalactic regions of the Universe. 

Kronberg's work also provides the first preview of small (arc minute - level) features that could be associated with unwanted and confusing foregrounds to the CMB radiation. Because these same radiation frequencies are to be imaged by the PLANCK CMB Explorer, corrections to the observed CMB for foreground fluctuations (the so-called microwave "cirrus clouds") are vitally important to using CMB fluctuations as a probe of the early Universe. 

In addition to Kronberg, other members of the research team included, Roland Kothes from DRAO, and Christopher Salter and Phil Perillat from Arecibo and the National Astronomy and Ionosphere Center. The DRAO is operated by the Herzberg Institute of Astrophysics and the National Research Council of Canada. 

Los Alamos National Laboratory, a multidisciplinary research institution engaged in strategic science on behalf of national security, is operated by Los Alamos National Security, LLC, a team composed of Bechtel National, the University of California, BWX Technologies, and Washington Group International for the Department of Energy's National Nuclear Security Administration. 

Los Alamos enhances national security by ensuring the safety and reliability of the U.S. nuclear stockpile, developing technologies to reduce threats from weapons of mass destruction, and solving problems related to energy, environment, infrastructure, health, and global security concerns.

SOURCE:SPACEFLIGHTNOW.COM
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 01/05/2007 20:55:16
Cosmologically speaking, diamonds may actually be forever
VANDERBILT UNIVERSITY NEWS RELEASE
Posted: April 30, 2007

NASHVILLE, Tenn. - If you've ever wondered about the ultimate fate of the universe, Lawrence Krauss and Robert Scherrer have some good news - sort of. 

In a paper published online on April 25 in the journal Physical Review D, the two physicists show that matter as we know it will remain as the universe expands at an ever-increasing clip. That is, the current status quo between matter and its alter ego, radiation, will continue as the newly discovered force of dark energy pushes the universe apart.

"Diamonds may actually be forever," quips Krauss, professor of physics and astronomy at Case Western Reserve University (CWRU) who is spending the year at Vanderbilt. "One of the only positive things that has arisen from the dark-energy dominated universe is that matter gets to beat radiation forever."

This viewpoint runs contrary to conventional wisdom among cosmologists. Today, there is more matter than radiation in the universe. But there were periods during the early universe that were dominated by radiation due to particle decays. The generally accepted view of the distant future has been that ordinary matter particles - protons and neutrons in particular - will gradually decay into radiation over trillions upon trillions of years, leaving a universe in which radiation once again dominates over matter; a universe lacking the material structures that are necessary for life.

It is only in the last decade that the existence of dark energy has been recognized. Before that Krauss and collaborators argued for its existence based on indirect evidence, but the first direct evidence came in 1998 when a major survey of exploding stars, called supernovae, revealed that the universe is apparently expanding at an increasing rate. Dark energy acts as a kind of anti-gravity that drives the expansion of the universe at large scales. Because it is associated with space itself, it is also called "vacuum energy." A number of follow-up observations have supported the conclusion that dark energy accounts for about 70 percent of all the energy in the universe.

"The discovery of dark energy has changed everything, but it has changed the view of the future more than the past. It is among the worst of all possible futures for life," says Krauss, who has spent the last few years exploring its implications. In an eternally expanding universe there is at least a chance that life could endure forever, but not in a universe dominated by vacuum energy, Krauss and CWRU collaborator Glenn Starkman have concluded. 

As the universe expands, the most distant objects recede at the highest velocity. The faster that objects recede, the more that the light coming from them is "red-shifted" to longer wavelengths. When their recessional velocity reaches light speed, they disappear because they are traveling away faster than the light that they emit. According to Krauss and Starkman, the process of disappearance has already begun: There are objects that were visible when the universe was half its present age that are invisible now. However, the process won't become really noticeable until the universe is about 100 billion years old. By ten trillion years, nothing but our local cluster of galaxies will be visible.

From the perspective of future civilizations, this process puts a finite limit on the amount of information and energy that will be available to maintain life. Assuming that consciousness is a physical phenomenon, this implies that life itself cannot be eternal, Krauss and Starkman argue. 

"Our current study doesn't change the process, but it does make it a little friendlier for matter and less friendly for radiation," says Scherrer, professor of physics at Vanderbilt. 

In their paper, Krauss and Scherrer analyzed all the ways that ordinary matter and dark matter could decay into radiation. (Dark matter is different from dark energy. It is an unknown form of matter that astronomers have only been able to detect by its gravitational effect on the ordinary matter in nearby galaxies. At this point, the physicists have no idea whether it is stable or will ultimately decay like ordinary matter.) Given known constraints on these various decay processes, the two show that none of them can produce radiation densities that exceed the density of the remaining matter. This is counter-intuitive because, when matter turns into energy, it does so according to Einstein's equation, E=mc2, and produces copious amounts of energy. 

"The surprising thing is that radiation disappears as fast as it is created in a universe with dark energy," says Krauss. 

The reason for radiation's vanishing act involves the expansion of space. Expanding space diminishes the density of radiant energy in two ways. The first is by increasing the separation between individual photons. The second is by reducing the amount of energy carried by individual photons. A photon's energy is contained entirely in its electromagnetic field. The shorter its wavelength and the higher its frequency, the more energy it contains. As space itself expands, the wavelengths of all the photons within it lengthen and their frequency drops. This means that the amount energy that individual photons contain also decreases. Taken together, these two effects dramatically reduce the energy density of radiation.

Protons and neutrons, by contrast, only suffer from the separation effect. Most of the energy that they carry is bound up in their mass and is not affected by spatial expansion. In an accelerating universe, that is enough of an advantage to maintain matter's dominance - forever. 

The research was funded by grants from the National Science Foundation and the U.S. Department of Energy. 

SOURCE:SPACEFLIGHTNOW.COM
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 05/05/2007 20:03:20
Astronomers discover a super-massive planet
HARVARD-SMITHSONIAN CENTER FOR ASTROPHYSICS NEWS RELEASE
Posted: May 2, 2007

CAMBRIDGE, MA - Today, astronomers at the Harvard-Smithsonian Center for Astrophysics (CfA) announced that they have found the most massive known transiting extrasolar planet. The gas giant planet, called HAT-P-2b, contains more than eight times the mass of Jupiter, the biggest planet in our solar system. Its powerful gravity squashes it into a ball only slightly larger than Jupiter.

HAT-P-2b shows other unusual characteristics. It has an extremely oval orbit that brings it as close as 3.1 million miles from its star before swinging three times farther out, to a distance of 9.6 million miles. If Earth's orbit were as elliptical, we would loop from almost reaching Mercury out to almost reaching Mars. Because of its orbit, HAT-P-2b gets enormously heated up when it passes close to the star, then cools off as it loops out again. Although it has a very short orbital period of only 5.63 days, this is the longest period planet known that transits, or crosses in front of, its host star.

"This planet is so unusual that at first we thought it was a false alarm - something that appeared to be a planet but wasn't," said CfA astronomer Gaspar Bakos. "But we eliminated every other possibility, so we knew we had a really weird planet."

Bakos is lead author of a paper submitted to the Astrophysical Journal describing the discovery.

HAT-P-2b orbits an F-type star, which is almost twice as big and somewhat hotter than the Sun, located about 440 light-years away in the constellation Hercules. Once every 5 days and 15 hours, it crosses directly in front of the star as viewed from Earth-a sort of mini-eclipse. Such a transit offers astronomers a unique opportunity to measure a planet's physical size from the amount of dimming.

Brightness measurements during the transit show that HAT-P-2b is about 1.18 times the size of Jupiter. By measuring how the star wobbles as the planet's gravity tugs it, astronomers deduced that the planet contains about 8.2 times Jupiter's mass. A person who weighs 150 pounds on Earth would tip the scale at 2100 pounds, and experience 14 times Earth's gravity, by standing on the visible surface (cloud tops) of HAT-P-2b.

CfA astronomer and co-author Robert Noyes said, "All the other known transiting planets are like 'hot Jupiters.' HAT-P-2b is hot, but it's not a Jupiter. It's much denser than a Jupiter-like planet; in fact, it is as dense as Earth even though it's mostly made of hydrogen."

"This object is close to the boundary between a star and a planet," said Harvard co-author Dimitar Sasselov. "With 50 percent more mass, it could have begun nuclear fusion for a short time."

An intriguing feature of HAT-P-2b is its highly eccentric (e=0.5) orbit. Gravitational forces between star and planet tend to circularize the orbit of a close-in planet. There is no other planet known with such an eccentric, close-in orbit. In addition, all other known transiting planets have circular orbits.

The most likely explanation is the presence of a second, outer world whose gravity pulls on HAT-P-2b and perturbs its orbit. Although existing data cannot confirm a second planet, they cannot rule it out either.

HAT-P-2b orbits the star HD 147506. With visual magnitude 8.7, HD 147506 is the fourth brightest star known to harbor a transiting planet, making the star (but not the planet) visible in a small, 3-inch telescope.

HAT-P-2b was discovered using a network of small, automated telescopes known as HATNet, which was designed and built by Bakos. The HAT network consists of six telescopes, four at the Smithsonian Astrophysical Observatory's Whipple Observatory in Arizona and two at its Submillimeter Array facility in Hawaii. As part of an international campaign, the Wise HAT telescope, located in the Negev desert (Israel) also took part in the discovery. The HAT telescopes conduct robotic observations every clear night, each covering an area of the sky 300 times the size of the full moon with every exposure. About 26,000 individual observations were made to detect the periodic dips of intensity due to the transit.

Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ukmicky on 06/05/2007 14:52:14
Baby fish home in on mother's reef
It's a case of "reef, sweet reef" for baby tropical fish, say researchers who have found a way of tracking the movements of two generations of fish. Their study shows that baby fish are able to find their way home to the reef their mother lived on.

"We have suspected this for a long time," says Michael Berumen of the University of Arkansas in the US. "But it has spawned a big debate. We know fish are capable of returning to their home reef, but do they really? Until now, we didn't know the answer to that."

To see if this "self-recruitment" really does happen in the wild, Berumen and his colleagues in Australia and France travelled to Kimbe Island near Papua New Guinea. On the reef that surrounds the island (pictured, right), they collected 176 female clownfish and 123 female butterflyfish.

Clownfish spawn their eggs in a nest but the larvae can spend about 10 days floating around in open water before settling on a reef. Butterflyfish, like snappers, groupers and many other species targeted by the fisheries industry, are pelagic spawners – meaning they spray their eggs and sperm into open water. The juveniles do not settle on a reef until 38 days later.

Radioactive tag
The researchers injected both species with small amounts of a barium isotope. After travelling through the females' bloodstream, the radioactive tag ends up in their eggs and eventually in an ear bone in their offspring.

"It's a really neat technique that they've developed to actually tag fish through a whole reproductive season," says Stephen Simpson of Edinburgh University in the UK. "Particularly for a species of pelagic spawners whose eggs are much more difficult to find."

The scientists returned to the reef about one month after having released the tagged females and this time collected juveniles and counted how many carried the barium isotope. The team calculated that about 60% of the juveniles on the reef were the offspring of females from that reef.

"For pelagic spawners, this means the females spew their eggs into the water column and somehow the eggs hatch and the larvae find their way back to the reef, which they've never seen," says Simpson.

In the case of Butterflyfish, "there are 5 to 6 weeks during which they are potentially out at sea," says Berumen.

Smelly and noisy
How the fish find their way back to the reef is another question. According to Simpson, reef fish scientists have traditionally been divided between those who believe the dispersal of offspring is at the mercy of currents and those who believe it is driven by the behaviour of the offspring. He belongs to the second group and has shown that reef fish are capable of recognising the sound of their home reef. Other scientists have shown than fish can pick out their reef by its smell.

But where does this ability to sense the home reef come from? Simpson has a possible explanation: "You could imagine there is a suite of genes passed on to the embryos, who are therefore pre-programmed as to what they should do once their ears, eyes and nostrils develop".

The new research may not just be a curiosity. The knowledge of the area over which the reef fish travel could help design better marine reserves.

For example, the scientists say reserves that are too large may not enable fish from the protected areas to re-supply the surrounding areas, where fishing continues

http://environment.newscientist.com/article/dn11778-baby-fish-home-in-on-mothers-reef.html

Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Karen W. on 13/07/2007 00:46:35
 
Red Orbit breaking News

http://www.redorbit.com/news/display/?id=747011

Posted on: Tuesday, 28 November 2006, 13:35 CST
Study Finds that a Single Impact Killed the Dinosaurs

(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi17.photobucket.com%2Falbums%2Fb73%2Fkarenw44%2Fresize.php.jpg&hash=fbc25c34752683891f97385a06ff845e)

Data supports the single-impact theory in a controversial discussion

COLUMBIA, Mo. – The dinosaurs, along with the majority of all other animal species on Earth, went extinct approximately 65 million years ago. Some scientists have said that the impact of a large meteorite in the Yucatan Peninsula, in what is today Mexico, caused the mass extinction, while others argue that there must have been additional meteorite impacts or other stresses around the same time.

A new study provides compelling evidence that "one and only one impact" caused the mass extinction, according to a University of Missouri-Columbia researcher.

"The samples we found strongly support the single impact hypothesis," said Ken MacLeod, associate professor of geological sciences at MU and lead investigator of the study. "Our samples come from very complete, expanded sections without deposits related to large, direct effects of the impact – for example, landslides – that can shuffle the record, so we can resolve the sequence of events well. What we see is a unique layer composed of impact-related material precisely at the level of the disappearance of many species of marine plankton that were contemporaries of the youngest dinosaurs. We do not find any sedimentological or geochemical evidence for additional impacts above or below this level, as proposed in multiple impact scenarios."

MacLeod and his co-investigators studied sediment recovered from the Demerara Rise in the Atlantic Ocean northeast of South America, about 4,500 km (approximately 2,800 miles) from the impact site on the Yucatan Peninsula. Sites closer to and farther from the impact site have been studied, but few intermediary sites such as this have been explored.

Interpretation of samples from locations close to the crater are complicated by factors such as waves, earthquakes and landslides that likely followed the impact and would have reworked the sediment. Samples from farther away received little impact debris and often don’t demonstrably contain a complete record of the mass extinction interval. The Demerara Rise samples, thus, provide an unusually clear picture of the events at the time of the mass extinction.

"With our samples, there just aren’t many complications to confuse interpretation. You could say that you’re looking at textbook quality samples, and the textbook could be used for an introductory class," MacLeod said. "It’s remarkable the degree to which our samples follow predictions given a mass extinction caused by a single impact. Sedimentological and paleontological complexities are minor, the right aged-material is present, and there is no support for multiple impacts or other stresses leading up to or following the deposition of material from the impact."

The impact of a meteorite on the Yucatan Peninsula likely caused massive earthquakes and tsunamis. Dust from the impact entered the atmosphere and blocked sunlight, causing plants to die and animals to lose important sources of food. Temperatures probably cooled significantly around the globe before warming in the following centuries, wildfires on an unprecedented scale may have burned and acid rain might have poured down.

MacLeod and many other scientists believe that these effects led to the relatively rapid extinction of most species on the planet. Some other scientists have argued that a single impact could not have caused the changes observed and say that the impact in the Yucatan predates the mass extinction by 300,000 years.

MacLeod’s co-investigators were Donna L. Whitney from the University of Minnesota, Brian T. Huber from the Smithsonian National Museum of Natural History and Christian Koeberl of the University of Vienna. The study was recently published in the ‘in press’ section of the online version of the Geological Society of America Bulletin. Funding was provided by the U.S. Science Support Program, the U.S. National Science Foundation and the Austrian Science Foundation. Samples were recovered on Leg 207 of the Ocean Drilling Program.

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Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 19/07/2007 13:07:40
Astronomers study a star born soon after the Big Bang
McDONALD OBSERVATORY NEWS RELEASE


AUSTIN ‹ How old are the oldest stars? An international team of astronomers led by Dr. Anna Frebel of The University of Texas at Austin McDonald Observatory recently measured the age of an ancient star in our Milky Way galaxy at an extraordinary 13.2 billion years. This measurement provides a lower limit to the age of the universe and will help to disentangle the chemical history of our galaxy. Frebel's results are published in today's edition of The Astrophysical Journal Letters.

The team used radioactive decay dating techniques to date the star, called HE 1523-0901. This is close to the age of the universe of 13.7 billion years. "This guy was born very shortly after the Big Bang," Frebel said.

"Surprisingly, it is very hard to pin down the age of a star," she said, "although we can generally infer that chemically primitive stars have to be very old." Such stars must have been born before many generations of stars had chemically enriched our galaxy.

Astronomers can only accurately measure the ages of very rare old stars that contain huge amounts of certain types of chemical elements, including radioactive elements like thorium and uranium.

Similar to the way archaeologists use carbon-14 and other elements to date Earth relics thousands of years old, astronomers use radioactive elements found in stars to deduce these stars' ages, which may be millions or billions of years.

"Very few stars display radioactive elements," Frebel said. "I'm looking at a very rare subgroup of these already rare stars. I'm looking for a needle in a haystack, really."

Frebel made the extremely difficult measurement of the amount of uranium in the star HE 1523-0901 using the UVES spectrograph on the Kueyen Telescope, one of four 8.2-meter telescopes that comprise The Very Large Telescope at the European Southern Observatory in Chile.

"This star is the best uranium detection so far," she said, explaining that while uranium has been discovered in two other stars previously, only one could be used to get a good age for the star. HE 1523-0901 also contains thorium, another radioactive element that is useful in age-dating of stars. Uranium, with a half-life of 4.5 billion years, is a better clock than thorium, Frebel says. Thorium's half-life of 14 billion years is actually longer than the age of the universe.

But astronomers need more than just radioactive elements like uranium and thorium to age-date a star. For each radioactive element, "you have to anchor it to another element within the star," Frebel said. Because she detected so many of these anchor elements in HE 1523-0901, she can come up with an extremely accurate age. In this case, the anchor elements are europium, osmium, and iridium.

The combination of two radioactive elements with three anchor elements discovered in this one star provided Frebel six so-called "cosmic clocks."

"So far, for no other star was it possible to employ more than one cosmic clock," she said. "Now we are suddenly provided with six measurements in just one star!"

How did she find this amazing star? Frebel says it was a case of "informed serendipity." She was researching a sample of old stars for her PhD thesis while a graduate student at The Australian National University, and recognized the consequences of this star's extraordinary spectrum after she measured it with ESO's Very Large Telescope.

"When you do discovery work, you never know what you're going to find," Frebel said. "You hope to find interesting objects. Depending on what you find, you then move in that direction."

The new result will be used by Frebel and her team to gain important clues to the creation and evolution of the chemical elements shortly after the Big Bang. It will also provide theorists with new, important experimental data. "Stars such as HE 1523-0901 are ideal cosmic laboratories to study nucleosynthesis," she said.

Frebel is now working with her colleagues Chris Sneden, Volker Bromm, Carlos Allende Prieto, Matthew Shetrone, and graduate student Ian Roederer at The University of Texas at Austin to further research extremely old stars with the 9.2-meter Hobby-Eberly Telescope at McDonald Observatory.

The Hobby-Eberly Telescope is a joint project of The University of Texas at Austin, The Pennsylvania State University, Stanford University, Ludwig-Maximilians-Universitat Munchen and Georg-August-Unversitat Gottingen.

SOURCE:SPACEFLIGHTNOW.com
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 19/07/2007 13:09:52
Exotic extrasolar planet is the hottest yet discovered
UNIVERSITY OF CENTRAL FLORIDA NEWS RELEASE


ORLANDO - University of Central Florida Physics Professor Joseph Harrington and his team have measured the hottest planet ever at 3700 degrees Fahrenheit.

"HD 149026b is simply the most exotic, bizarre planet," Harrington said. "It's pretty small, really dense, and now we find that it's extremely hot."



 
 
Using Spitzer, NASA's infrared space telescope, Harrington and his team observed the tiny planet disappear behind its star and reappear. Although the planet cannot be seen separately from the star, the dimming of the light that reached Spitzer told the scientists how much light the hot planet emits. From this they deduced the temperature on the side of the planet facing its star. The team's findings were published online in Nature today.

Discovered in 2005, HD 149026b is a bit smaller than Saturn, making it the smallest extrasolar planet with a measured size. However, it is more massive than Saturn, and is suspected of having a core 70-90 times the mass of the entire Earth. It has more heavy elements (material other than hydrogen and helium) than exist in our whole solar system, outside the Sun.

There are more than 230 extrasolar planets, but this is only the fourth of these to have its temperature measured directly. It is simple to explain the temperatures of the other three planets. However, for HD 149026b to reach 3700 degrees, it must absorb essentially all the starlight that reaches it. This means the surface must be blacker than charcoal, which is unprecedented for planets. The planet would also have to re-radiate all that energy in the infrared.

"The high heat would make the planet glow slightly, so it would look like an ember in space, absorbing all incoming light but glowing a dull red," said Harrington.

Drake Deming, of NASA's Goddard Space Flight Center in Greenbelt, MD, and a co-author of the Nature paper, thinks theorists are going to be scratching their heads over this one. "This planet is off the temperature scale that we expect for planets, so we don't really understand what's going on," Deming said. "There may be more big surprises in the future."

Harrington's team on this project also included Statia Luszcz from the Center for Radiophysics and Space Research at Cornell University, who is now a graduate student at the University of California, Berkeley. Sara Seager, a theorist in the Departments of Earth, Atmospheric, and Planetary Sciences and of Physics at the Massachusetts Institute of Technology, and Jeremy Richardson, an observer from the Exoplanet and Stellar Astrophysics Laboratory at NASA Goddard, round out the team.

Harrington is no stranger to significant findings. His research was published in Science magazine in October 2006 and in Nature in February 2007. In the first of those papers, Harrington's team used Spitzer to make the first measurement of day and night temperature variation on a different extrasolar planet. That research found that a Jupiter-like gas-giant planet circling very close to its sun is as hot as fire on one side, and potentially as cold as ice on the other, a condition that may also hold for HD 149026b.

February's publication documented a landmark achievement. In a project led by Richardson, the group captured enough light from an exoplanet to spread it apart into a spectrum and find signatures of molecules in the planet's atmosphere -- a key step toward being able to detect life on alien worlds.

Harrington's team fared well in this year's stiff competition for observing time on NASA's orbiting infrared facility. They will observe HD 149026b using all of Spitzer's instruments in the coming year, to gain a better understanding of the planet's atmosphere. Harrington is a professor in UCF's growing program in planetary sciences.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center, Pasadena, Calif. JPL is a division of California Institute for Technology, Pasadena.
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 19/07/2007 13:17:52
Scientist finds a new way to the center of the Earth
NASA/JPL NEWS RELEASE


PASADENA, Calif. -- Humans have yet to see Earth's center, as did the characters in Jules Verne's science fiction classic, "Journey to the Center of the Earth." But a new NASA study proposes a novel technique to pinpoint more precisely the location of Earth's center of mass and how it moves through space.

Knowing the location of the center of mass, determined using measurements from sites on Earth's surface, is important because it provides the reference frame through which scientists determine the relative motions of positions on Earth's surface, in its atmosphere and in space. This information is vital to the study of global sea level change, earthquakes, volcanoes and Earth's response to the retreat of ice sheets after the last ice age.

The accuracy of estimates of the motion of Earth's center of mass is uncertain, but likely ranges from 2 to 5 millimeters (.08 to .20 inches) a year. Donald Argus of NASA's Jet Propulsion Laboratory, Pasadena, Calif., developed the new technique, which estimates Earth's center of mass to within 1 millimeter (.04 inches) a year by precisely positioning sites on Earth's surface using a combination of four space-based techniques. The four techniques were developed and/or operated by NASA in partnership with other national and international agencies. Results of the new study appear in the June issue of Geophysical Journal International.

Scientists currently define Earth's center in two ways: as the mass center of solid Earth or as the mass center of Earth's entire system, which combines solid Earth, ice sheets, oceans and atmosphere. Argus says there is room for improvement in these estimates.

"The past two international estimates of the motion of the Earth system's mass center, made in 2000 and 2005, differ by 1.8 millimeters (.07 inches) a year," he said. "This discrepancy suggests the motion of Earth's mass center is not as well known as we'd like."

Argus argues that movements in the mass of Earth's atmosphere and oceans are seasonal and do not accumulate enough to change Earth's mass center. He therefore believes the mass center of solid Earth provides a more accurate reference frame.

"By its very nature, Earth's reference frame is moderately uncertain no matter how it is defined," Argus said. "The problem is very much akin to measuring the center of mass of a glob of Jell-O, because Earth is constantly changing shape due to tectonic and climatic forces. This new reference frame takes us a step closer to pinpointing Earth's exact center."

Argus says this new reference frame could make important contributions to understanding global climate change. The inference that Earth is warming comes partly from observations of global sea level rise, believed to be due to ice sheets melting in Greenland, Antarctica and elsewhere. In recent years, global sea level has been rising faster, with the current rate at about 3 millimeters (.12 inches) a year. Uncertainties in the accuracy of the motion of Earth's center of mass result in significant uncertainties in measuring this rate of change.

"Knowing the relative motions of the mass center of Earth's system and the mass center of the solid Earth can help scientists better determine the rate at which ice in Greenland and Antarctica is melting into the ocean," Argus explained. He said the new frame of reference will improve estimates of sea level rise from satellite altimeters like the NASA/French Space Agency Jason satellite, which rely on measurements of the location and motion of the mass center of Earth's system.

"For scientists studying post-glacial rebound, this new reference frame helps them better understand how viscous [gooey or sticky] Earth's solid mantle is, which affects how fast Earth's crust rises in response to the retreat of the massive ice sheets that covered areas such as Canada 20,000 years ago," he said. "As a result, they'll be able to make more accurate estimates of these vertical motions and can improve model predictions."

Scientists can also use the new information to more accurately determine plate motions along fault zones, improving our understanding of earthquake and volcanic processes.

The new technique combines data from a high-precision network of global positioning system receivers; a network of laser stations that track high-orbiting geodetic satellites called Laser Geodynamics Satellites, or Lageos; a network of radio telescopes that measure the position of Earth with respect to quasars at the edge of the universe, known as very long baseline interferometry; and a French network of precise satellite tracking instruments called Doppler Orbit and Radiopositioning Integrated by Satellite, or DORIS.

JPL is managed for NASA by the California Institute of Technology in Pasadena.

SOURCE:SPACEFLIGHTNOW.com

Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 19/07/2007 16:18:12
New research proves single origin of humans in Africa
New research published in the journal Nature (19 July) has proved the single origin of humans theory by combining studies of global genetic variations in humans with skull measurements across the world. The research, at the University of Cambridge and funded by the Biotechnology and Biological Sciences Research Council (BBSRC), represents a final blow for supporters of a multiple origins of humans theory.

Competing theories on the origins of anatomically modern humans claim that either humans originated from a single point in Africa and migrated across the world, or different populations independently evolved from homo erectus to home sapiens in different areas.

The Cambridge researchers studied genetic diversity of human populations around the world and measurements of over 6,000 skulls from across the globe in academic collections. Their research knocks down one of the last arguments in favour of multiple origins. The new findings show that a loss in genetic diversity the further a population is from Africa is mirrored by a loss in variation in physical attributes.

Lead researcher, Dr Andrea Manica from the University's Department of Zoology, explained: "The origin of anatomically modern humans has been the focus of much heated debate. Our genetic research shows the further modern humans have migrated from Africa the more genetic diversity has been lost within a population.

"However, some have used skull data to argue that modern humans originated in multiple spots around the world. We have combined our genetic data with new measurements of a large sample of skulls to show definitively that modern humans originated from a single area in Sub-saharan Africa."

The research team found that genetic diversity decreased in populations the further away from Africa they were - a result of 'bottlenecks' or events that temporarily reduced populations during human migration. They then studied an exceptionally large sample of human skulls. Taking a set of measurements across all the skulls the team showed that not only was variation highest amongst the sample from south eastern Africa but that it did decrease at the same rate as the genetic data the further the skull was away from Africa.

To ensure the validity of their single origin evidence the researchers attempted to use their data to find non-African origins for modern humans. Research Dr Francois Balloux explains: "To test the alternative theory for the origin of modern humans we tried to find an additional, non-African origin. We found this just did not work. Our findings show that humans originated in a single area in Sub-Saharan Africa."


SOURCE: EUREKALERT.ORG
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 31/07/2007 23:10:06
Supergiant star spews molecules needed for life
UNIVERSITY OF ARIZONA NEWS RELEASE
Posted: July 30, 2007

University of Arizona astronomers who are probing the oxygen-rich environment around a supergiant star with one of the world's most sensitive radio telescopes have discovered a score of molecules that include compounds needed for life.

"I don't think anyone would have predicted that VY Canis Majoris is a molecular factory. It was really unexpected," said Arizona Radio Observatory (ARO) Director Lucy Ziurys, UA professor of astronomy and of chemistry. "Everyone thought that the interesting chemistry in gas clouds around old stars was happening in envelopes around nearer, carbon-rich stars," Ziurys said. "But when we started looking closely for the first time at an oxygen-rich object, we began finding all these interesting things that weren't supposed to be there."

VY Canis Majoris, one of the most luminous infrared objects in the sky, is an old star about 5,000 light years away. It's a half million times more luminous than the sun, but glows mostly in the infrared because it's a cool star. It truly is "supergiant" -- 25 times as massive as the sun and so huge that it would fill the orbit of Jupiter. But the star is losing mass so fast that in a million years -- an astronomical eyeblink -- it will be gone. The star already has blown away a large part of its atmosphere, creating its surrounding envelope that contains about twice as much oxygen as carbon.

Ziurys and her colleagues are not yet halfway through their survey of VY Canis Majoris, but they've already published in the journal, Nature (June 28 issue), about their observations of a score of chemical compounds. These include some molecules that astronomers have never detected around stars and are needed for life.

Among the molecules Ziurys and her team reported in Nature are table salt (NaCl); a compound called phosphorus nitride (PN), which contains two of the five most necessary ingredients for life; molecules of HNC, which is a variant form of the organic molecule, hydrogen cyanide; and an ion molecule form of carbon monoxide that comes with a proton attached (HCO+). Astronomers have found very little phosphorus or ion molecule chemistry in outflows from cool stars until now.

"We think these molecules eventually flow from the star into the interstellar medium, which is the diffuse gas between stars. The diffuse gas eventually collapses into denser molecular clouds, and from these solar systems eventually form," Ziurys said.

Comets and meteorites dump about 40,000 tons of interstellar dust on Earth each year. We wouldn't be carbon-based life forms otherwise, Ziurys noted, because early Earth lost all of its original carbon in the form of a methane atmosphere.

"The origin of organic material on Earth -- the chemical compounds that make up you and me -- probably came from interstellar space. So one can say that life's origins really begin in chemistry around objects like VY Canis Majoris."

Astronomers previously studied VY Canis Majoris with optical and infrared telescopes. "But that's kind of like diving in with a butcher knife to look at what's there, when what you need is an oyster fork," Ziurys said.

The Arizona Radio Observatory's 10-meter Submillimeter Telescope (SMT) on Mount Graham, Ariz., excels as a sensitive stellar "oyster fork." Chemical molecules each possess their own unique radio frequencies. The astronomers identify the unique radio signatures of chemical compounds in laboratory work, enabling them to identify the molecules in space.

The ARO team recently began testing a new receiver in collaboration with the National Radio Astronomy Observatory. The receiver was developed as a prototype for the Atacama Large Millimeter Array, a telescope under construction in Chile. The state-of-the-art receiver has given the SMT 10 times more sensitivity at millimeter wavelengths than any other radio telescope. The SMT can now detect emission weaker than a typical light bulb from distant space at very precise frequencies.

The UA team has discovered that the molecules aren't just flowing out as a gas sphere around VY Canis Majoris, but also are blasting out as jets through the spherical envelope.

"The signals we receive show not only which molecules are seen, but how the molecules are moving toward and away from us," said Stefanie Milam, a recent doctoral graduate on the ARO team.

The molecules flowing out from VY Canis Majoris trace complex winds in three outflows: the general, spherical outflow from the star, a jet of material blasting out towards Earth, and another jet shooting out a 45 degree angle away from Earth.

Astronomers have seen bipolar outflows from stars before, but not two, unconnected, asymmetric and apparently random outflows, Ziurys said.

Ziurys said she believes the two random jets are evidence for what astronomers earlier proposed are "supergranules" that form in very massive stars, and has been seen in Betelgeuse. Supergranules are huge cells of gas that form inside the star, then float to the surface and are ejected out of the star, where they cool in space and form molecules, creating jet outflows with certain molecular compositions.

Back in the 1960s, no one believed molecules could survive the harsh environment of space. Ultraviolet radiation supposedly reduced matter to atoms and atomic ions. Now scientists conclude that at least half of the gas in space between the stars within the 33-light-year inner galaxy is molecular, Ziurys said. "Our results are more evidence that we live in a really molecular universe, as opposed to an atomic one," Ziurys said.

The Arizona Radio Observatory (ARO) owns and operates two radio telescopes in southern Arizona: The former NRAO 12 Meter (KP12m) Telescope located 50 miles southwest of Tucson on Kitt Peak and the Submillimeter Telescope (SMT) located on Mount Graham near Safford, Ariz. The telescopes are operated around-the-clock for about nine to 10 months per year for a combined 10,000 hours per observing season. About 1,500 hours are dedicated to sub-mm wavelengths at the SMT. The ARO offices are centrally located in the Steward Observatory building on the UA campus in Tucson.


SOURCE: http://spaceflightnow.com/news/n0707/30supergiant/
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 31/07/2007 23:13:39
Satellites unveil new type of active galaxy
NASA-GODDARD NEWS RELEASE
Posted: July 30, 2007

GREENBELT, Md. - An international team of astronomers using NASA's Swift satellite and the Japanese/U.S. Suzaku X-ray observatory has discovered a new class of active galactic nuclei (AGN).

By now, you'd think that astronomers would have found all the different classes of AGN - extraordinarily energetic cores of galaxies powered by accreting supermassive black holes. AGN such as quasars, blazars, and Seyfert galaxies are among the most luminous objects in our Universe, often pouring out the energy of billions of stars from a region no larger than our solar system. (NEIL EDIT: HOLY COW !!!!....that's well bright !!!)
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fbestsmileys.com%2Fsigns11%2F3.gif&hash=9f963ec942c95b89b97516edb75a6d2a)

But by using Swift and Suzaku, the team has discovered that a relatively common class of AGN has escaped detection...until now. These objects are so heavily shrouded in gas and dust that virtually no light gets out.

"This is an important discovery because it will help us better understand why some supermassive black holes shine and others don't," says astronomer and team member Jack Tueller of NASA's Goddard Space Flight Center in Greenbelt, Md.

Evidence for this new type of AGN began surfacing over the past two years. Using Swift's Burst Alert Telescope (BAT), a team led by Tueller has found several hundred relatively nearby AGNs that were previously missed because their visible and ultraviolet light was smothered by gas and dust. The BAT was able to detect high-energy X-rays from these heavily blanketed AGNs because, unlike visible light, high-energy X-rays can punch through thick gas and dust.

To follow up on this discovery, Yoshihiro Ueda of Kyoto University, Japan, Tueller, and a team of Japanese and American astronomers targeted two of these AGNs with Suzaku. They were hoping to determine whether these heavily obscured AGNs are basically the same type of objects as other AGN, or whether they are fundamentally different. The AGNs reside in the galaxies ESO 005-G004 and ESO 297-G018, which are about 80 million and 350 million light-years from Earth, respectively.

Suzaku covers a broader range of X-ray energies than BAT, so astronomers expected Suzaku to see X-rays across a wide swath of the X-ray spectum. But despite Suzaku's high sensitivity, it detected very few low- or medium-energy X-rays from these two AGN, which explains why previous X-ray AGN surveys missed them.

According to popular models, AGNs are surrounded by a donut-shaped ring of material, which partially obscures our view of the black hole. Our viewing angle with respect to the donut determines what type of object we see. But team member Richard Mushotzky, also at NASA Goddard, thinks these newly discovered AGN are completely surrounded by a shell of obscuring material. "We can see visible light from other types of AGN because there is scattered light," says Mushotzky. "But in these two galaxies, all the light coming from the nucleus is totally blocked."

Another possibility is that these AGN have little gas in their vicinity. In other AGN, the gas scatters light at other wavelengths, which makes the AGN visible even if they are shrouded in obscuring material.

"Our results imply that there must be a large number of yet unrecognized obscured AGNs in the local universe," says Ueda.

In fact, these objects might comprise about 20 percent of point sources comprising the X-ray background, a glow of X-ray radiation that pervades our Universe. NASA's Chandra X-ray Observatory has found that this background is actually produced by huge numbers of AGNs, but Chandra was unable to identify the nature of all the sources.

By missing this new class, previous AGN surveys were heavily biased, and thus gave an incomplete picture of how supermassive black holes and their host galaxies have evolved over cosmic history. "We think these black holes have played a crucial role in controlling the formation of galaxies, and they control the flow of matter into clusters," says Tueller. "You can't understand the universe without understanding giant black holes and what they're doing. To complete our understanding we must have an unbiased sample."

The discovery paper will appear in the August 1st issue of the Astrophysical Journal Letters.

SOURCE:http://spaceflightnow.com/news/n0707/30galaxy/
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 12/08/2007 19:05:58
Planet orbiting a giant red star discovered


A planet orbiting a giant red star has been discovered by an astronomy team led by Penn State's Alex Wolszczan, who in 1992 discovered the first planets ever found outside our solar system. The new discovery is helping astronomers to understand what will happen to the planets in our solar system when our Sun becomes a red-giant star, expanding so much that its surface will reach as far as Earth's orbit.

The star is 2 times more massive and 10 times larger than the Sun. The new planet circles the giant star every 360 days and is located about 300 light years from Earth, in the constellation Perseus. A paper describing the discovery will be published in a November 2007 issue of the Astrophysical Journal.

The discovery resulted from an ongoing effort that the research team began three years ago to find Jupiter-mass planets around red-giant stars that are typically farther from Earth than those included in most other planet searches.

"After astronomers have spent more than 10 years searching for planets around Sun-like stars and discovering over 250 planets elsewhere in our galactic neighborhood, we still do not know whether our solar system's properties, including life-supporting conditions on our planet, are typical or exceptional among solar systems throughout the Galaxy," Wolszczan says. "The picture for now, based on the searches for planets around stars like our Sun, is that our planetary system appears to be unusual in a number of ways."

"This planet is the first one discovered by Penn State astronomers with the Hobby-Eberly Telescope, and it is in one of the most distant of the ten published solar systems discovered around red-giant stars," comments Lawrence Ramsey, a member of the discovery team and the head of the Department of Astronomy and Astrophysics at Penn State. Ramsey is a leader in the conception, design, construction, and operation of the Hobby-Eberly Telescope. "We are now becoming serious participants in planetary searches and planetary astronomy using the Hobby-Eberly Telescope," he says.

Astronomers now are branching out with different strategies for searching for planets, with the hope of more quickly detecting life elsewhere in the universe, of discovering all the possible kinds of solar systems, and of learning how they form around different kinds of stars. Wolszczan's team used one of these new strategies -- searching for planets around giant stars, which have evolved to a later stage of life than our Sun's.

"We have compiled a catalog of nearly a thousand giant stars that are candidates for hosting solar systems," Wolszczan says.

Because the method for discovering planets involves repeated measurements of their gravitational effect on the star they circle, and because planets around red giants can take years to make one orbit around the star, the research team is just now beginning to reap discoveries from years of systematic observations.

"It took us 3 years to gather enough data on over 300 stars to start identifying those that are good candidates for having planetary companions," Wolszczan said. "This planet is just the first of a number of planet discoveries that this research program is likely to produce."

This research is a collaboration between astronomers at Penn State, Nicholas Copernicus University in Poland, the McDonald Observatory, and the California Institute of Technology.

"One important aspect of this work is that it marks the debut of a research group in Poland, led by Dr. Andrzej Niedzielski, which has become a serious contributor to discoveries in extra-solar planetary astronomy," Wolszczan said.

One reason for studying solar systems that include red-giant stars is that they help astronomers to understand more about the future of our own solar system -- as family photos can give children an idea of what they might look like when they are the age of their grandparents.

"Our Sun probably will make the Earth unhabitable in about 2 billion years because it will get hotter and hotter as it evolves on its way to becoming a red giant about 5 billion years from now," Wolszczan says.

As the star swells up, transforming itself into a red giant, it affects the orbits of its planets and the dynamics of the whole planetary system, causing such changes as orbit crossings, planet collisions, and the formation of new planets out of the debris of those collisions.

"When our Sun becomes a red giant, Earth and the other inner planets very likely will dive into it and disappear," Wolszczan says.

Another motivation for studying red-giant stars is to understand how their habitable zones move farther out as the star's radiating surface becomes bigger. Based on how long it took for life to develop on Earth, scientists speculate that there is more than enough time during a star's giant phase for life to get a start somewhere in the evolving habitable zones.

"In our solar system, places like Europa -- a satellite of Jupiter that now is covered by a thick layer of water ice -- might warm up enough to support life for more than a billion years or so, over the time when our Sun begins to evolve into a red giant, making life on Earth impossible," Wolszczan said.

The method the astronomers use to discover planets is to observe candidate stars, repeatedly measuring their space velocity using the Doppler effect -- the changes in the star's light spectrum that result from its being pulled alternately toward and away from Earth by the gravity of an orbiting planet.

"When we detect a significant difference in a star's velocity over a month or two, we then start observing that star more frequently," Wolszczan says. "In this paper, the velocity of the star changed by about 50 meters per second (about 100 miles per hour) between our first and second observations, so we observed that star more frequently and we found a clearly repeatable effect, indicating the presence of a planet." A star and its orbiting planet move around the center-of-mass of the whole system, so the star alternately approaches and recedes from Earth periodically. "When the star gets closer to us, its light becomes a little bit bluer and when it recedes from us, its light becomes redder, and we can measure that effect to deduce the presence of planets," Wolszczan explains.

Searching for planets around giant stars also is a clever way to learn about the formation of planets around stars more massive than our Sun. Because massive stars are so hot when they are in the phase of life of our Sun, astronomers have not been able to detect enough of their spectral lines to use the Doppler-spectroscopy method of finding planets. However, these stars become cooler as they evolve into giants, at which point the spectral-line observations needed for Doppler detection of planets become possible. "We want to know how often do planets form around stars that were more massive than our Sun," Wolszczan said. "Obviously, the more solar systems around red giants we discover and study, the better chance we have to really understand the big picture of planet formation."

Another reason astronomers are trying to discover planets around different kinds of stars at different stages of stellar evolution is to find out how different kinds of planetary systems change when their stars become red giants and how they ultimately end their lives as burnt-out, shrunken white-dwarfs.

"We really are at the very beginning of this effort and it is going to take time to get a consistent picture of planetary formation and evolution," Wolszczan says. "The more we learn, the greater the chance will be that sooner or later we will discover how ordinary or extraordinary is our home -- the Earth's solar system."

SOURCE: SPACEFLIGHTNOW.COM
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 12/08/2007 19:27:22


An Early Ape Shows Its Hand (8/8/07)

Fossils often have provided important insights into the evolution of humans and our ancestors. Even small fossils, such as bones from the hand or foot can tell us much about our ancestor’s and their behavior. Such may be the case with an ape that lived more than nine million years ago.

A study published in the latest journal issue of Proceedings of the Royal Society B: Biological Sciencesreports on the structure of the hand of Hispanopithecus, a critically important fossil from an ape that lived during the late Miocene of Spain. While the authors ponder that the fossil may be from a direct ancestor of living great apes (especially the orangutan), Dr. C. Owen Lovejoy, Kent State University Professor of Anthropology, suggests another possibility in his comment on the article published in the same issue.

A preeminent biological anthropologist in the study of human origins, Lovejoy suggests that the fossil may belong to an extinct ape with its own unique locomotor behavior—a special adaptation and unique form of locomtion that left no modern descendants.

In 2007, Lovejoy was elected to membership in the prestigious National Academy of Sciences for his excellence in original scientific research.

SOURCE:EUREKALERT.ORG
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 12/08/2007 19:28:47
Beyond Mesopotamia:

 A radical new view of human civilization reported in Science
Many urban centers crossed arc of Middle Asia 5,000 years ago

A radically expanded view of the origin of civilization, extending far beyond Mesopotamia, is reported by journalist Andrew Lawler in the 3 August issue of Science.

Mesopotamia is widely believed to be the cradle of civilization, but a growing body of evidence suggests that in addition to Mesopotamia, many civilized urban areas existed at the same time – about 5,000 years ago – in an arc that extended from Mesopotamia east for thousands of kilometers across to the areas of modern India and Pakistan, according to Lawler.

“While Mesopotamia is still the cradle of civilization in the sense that urban evolution began there,” Lawler said, “we now know that the area between Mesopotamia and India spawned a host of cities and cultures between 3000 B.C.E. and 2000 B.C.E.”

Evidence of shared trade, iconography and other culture from digs in remote areas across this arc were presented last month at a meeting in Ravenna, Italy of the International Association for the Study of Early Civilizations in the Middle Asian Intercultural Space. The meeting was the first time that many archaeologists from more than a dozen countries gathered to discuss the fresh finds that point to this new view of civilization’s start. Science’s Lawler was the only journalist present.

Archaeologists shared findings from dozens of urban centers of approximately the same age that existed between Mesopotamia and the Indus River valley in modern day India and Pakistan. The researchers are just starting to sketch out this new landscape, but it’s becoming clear that these centers traded goods and could have shared technology and architecture. Recovered artifacts such as beads, shells, vessels, seals and game boards show that a network linked these civilizations.

Researchers have also found hints, such as similar ceremonial platforms, that these cultures interacted and even learned from one another. A new excavation near Jiroft in southeastern Iran, for example, has unearthed tablets with an unknown writing system. This controversial find highlights the complexity of the cultures in an area long considered a backwater, Lawler explained.

These urban centers are away from the river valleys that archaeologists have traditionally focused on, according to Lawler. Archaeologists now have access to more remote locations and are expanding their studies.

SOURCE:EUREKALERT.ORG
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 23/08/2007 19:40:20
What makes Mars magnetic?
EUROPEAN SCIENCE FOUNDATION NEWS RELEASE
Posted: August 22, 2007

*This'll interest some geologists, I think one or two may frequent the site*

Earth's surface is a very active place; its plates are forever jiggling around, rearranging themselves into new configurations. Continents collide and mountains arise, oceans slide beneath continents and volcanoes spew. As far as we know Earth's restless surface is unique to the planets in our solar system. So what is it that keeps Earth's plates oiled and on the move?

Scientists think that the secret lies beneath the crust, in the slippery asthenosphere. In order for the mantle to convect and the plates to slide they require a lubricated layer. On Mars this lubrication has long since dried up, but on Earth the plates can still glide around with ease.

If you could pick up a rock from the surface of Mars, then the chances are it would be magnetic. And yet, Mars doesn't have a magnetic field coming from its core. These rocks are clinging to the signal of an ancient magnetic field, dating back billions of years, to the times when Mars had a magnetic field like Earth's.

So how have these rocks hung onto their magnetic directions and what do they tell us about Mars? Strangely, the answer to these questions might be sitting here on Earth.

Most continental rocks on Earth align their magnetic moments with the current magnetic field - they are said to have -induced' magnetism. "I consider induced rocks to have -Alzheimers'. These are the rocks that forgot where they were born and how to get home," explains Suzanne McEnroe from the Geological Survey of Norway at a European Science Foundation, EuroMinScI conference near Nice, France this year.

However, not all of Earth's continental rocks have an induced magnetization. Some rocks stubbornly refuse to swing with the latest magnetic field, and instead keep hold of the direction they were born with. These rocks are said to have a remanent magnetization.

McEnroe and her colleagues have been studying some of Earth's strongest and oldest remanent magnetic rocks, to find out why they have such good memories. Understanding these rocks may give us clues as to what kind of rocks lie on Mars.

One of their research projects (in cooperation with Phil Schmidt and David Clark at CSIRO, Australia and just published in the Journal of Geophysical Research) is on the Peculiar Knob Formation in South Australia. These rocks are around 1 billion years old and have a strong magnetic remanence, more than 30 times larger than typically found in basaltic rocks.

"This particular research evolved from looking for an economic mineral deposit," says McEnroe. The mining company had assumed that the rocks in this strongly magnetic area were holding an induced magnetic field and that there would be magnetite buried down below. However, they were puzzled when a different mineral - hematite, came out of the drill core. Had they missed their target, or were their assumptions wrong?

By studying the samples under a powerful microscope and modelling their magnetic properties, McEnroe was able to show that the hematite was responsible for the strong magnetic field and that it was holding a remanent field from around 1 billion years ago. "We could see that the hematite contained small intergrowths that carried the magnetism," says McEnroe, who presented her findings at the 1st EuroMinScI Conference near Nice, France in March this year.

And it turns out that the microstructure of the rock is the key to whether it can hold a remanent magnetization or not. Together with Richard Harrison, a mineral physicist at Cambridge University, UK, and Peter Robinson at NGU, McEnroe has been studying strong remanent magnetic rocks from a variety of places including Scandinavia and the USA.

A study on nearly billion-year-old rocks in Norway showed a remanent magnetic anomaly comparable in scale to those observed on Mars.  The remanent magnetic anomaly dominates the local magnetic field to such a degree that more than half the Earth's field is cancelled.  It is nearly impossible to use a compass in the area, which cannot point correctly north because of the strong remanent magnetization in the rocks.

What they have found is that rocks containing nanometre scale intergrowths of ilmenite and hematite are better able to cling onto their original magnetization than those without such fine-scale features. "Placing a nanoparticle of ilmenite into the hematite host creates a strong and stable magnetic signal that can survive large changes in temperature and magnetic field over billions of years," explains Harrison.

So can this tell us anything about the rocks on Mars? "These rocks are good analogues for the magnetic rocks we see on Mars because of their strong magnetism and the length of time they have retained this memory," says McEnroe. Certainly this nano-scale microstructure is a plausible candidate for the magnetic rocks on Mars.

However, the rocks on Earth can't answer all our questions. "There is not going to be one mineral or one tectonic setting on Mars. There are going to be different reasons that enhance the signature in different places," says McEnroe. The only way to definitively answer the question is to go and pick up some rocks from Mars. 


SOURCE:SPACEFLIGHTNOW.COM
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 23/08/2007 19:43:13
Astronomers spot brightest galaxies in distant universe
CENTER FOR ASTROPHYSICS NEWS RELEASE
Posted: August 22, 2007

CAMBRIDGE, MA - By combining the capabilities of several telescopes, astronomers have spotted extremely bright galaxies hiding in the distant, young universe. The newfound galaxies are intrinsically bright due to their large rate of star formation-1000 times greater than the Milky Way. However, much of that light is hidden by surrounding dust and gas, leaking out only in the infrared.

The galaxies are located about 12 billion light-years away, and existed when the universe was less than 2 billion years old. They are the most luminous and massive galaxies seen at that great distance. Smaller, dimmer galaxies were much more common in the early universe because it takes time for galaxies to form and grow.

"It's a real surprise to find galaxies that massive and luminous existing so early in the universe," said astronomer Giovanni Fazio of the Harvard-Smithsonian Center for Astrophysics (CfA). "We are witnessing the moment when the most massive galaxies in the universe were forming most of their stars in their early youth."

"It's tough to explain how such bright, massive, dusty galaxies formed so early in the lifetime of the universe," added Harvard graduate student Josh Younger.

The hide-and-seek galaxies initially were spotted with the AzTEC imaging camera on the James Clerk Maxwell Telescope. The camera, developed by a team led by Grant Wilson and Min Yun of the University of Massachusetts at Amherst, discovered several hundred previously unseen galaxies that were bright at millimeter and submillimeter wavelengths.

A team of astronomers made follow-up observations of the seven brightest galaxies in an area of the sky studied by the Cosmic Evolution Survey (COSMOS). The Smithsonian's Submillimeter Array pinpointed the exact location of each galaxy, allowing the team to confirm that the source was a single galaxy and not a blend of several fainter galaxies.

Once precise locations were known, additional observations were made with the Hubble Space Telescope, the Spitzer Space Telescope, and the Very Large Array of radio telescopes. Even Hubble's powerful vision did not detect the galaxies, confirming that they are shrouded in dust that blocks visible light. Spitzer could penetrate the dust and detect the stars directly. The Very Large Array detected only the two closest galaxies.

By combining these measurements, the astronomers showed that five of the seven AzTEC galaxies are located at redshifts greater than 3, which corresponds to a distance of 12 billion light-years.

"These results suggest that the brightest submillimeter galaxies may be the most distant," said Fazio.

The galaxies' large infrared brightness indicates that they are forming new stars rapidly, probably due to collisions and mergers.

"The source of the infrared radiation seems to be very compact, which suggests that they are colliding galaxies that may eventually evolve into quasars," said Younger.

In the future, the astronomers plan to image more sources of submillimeter radiation in different cosmic environments, to try to better understand the population.

"We also plan to use the most extended configuration of the SMA to zoom in and try to resolve these objects, and really narrow down the source of their extreme infrared luminosity," added Younger.

Headquartered in Cambridge, Mass., the Harvard-Smithsonian Center for Astrophysics (CfA) is a joint collaboration between the Smithsonian Astrophysical Observatory and the Harvard College Observatory. CfA scientists, organized into six research divisions, study the origin, evolution and ultimate fate of the universe

SOURCE:SPACEFLIGHTNOW.COM
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: paul.fr on 27/08/2007 20:47:48
We have developed several devices for positioning organic molecules, molecular aggregates, cells, and single-cell organisms onto solid supports. These printers can create stable, functional protein arrays using an inexpensive technology. The cell printer allows us to create cell libraries as well as cellular assemblies that mimic their respective position in organs. The printers are derived from commercially available ink-jet printers that are modified to dispense protein or cell solutions instead of ink. We describe here the modifications to the print heads, and the printer hardware and software that enabled us to adapt the ink-jet printers for the manufacture of cell and protein arrays. The printers have the advantage of being fully automated and computer controlled, and allow for the high-throughput manufacture of protein and cell arrays.

http://www.citeulike.org/user/rodney/article/1567867

bubble jet printers are also being used to make batteries that are...er, paper thin.
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 13/10/2007 15:23:28
Gamma-ray lighthouse at the edge of our universe
EUROPEAN SPACE AGENCY NEWS RELEASE


There is a gamma-ray lighthouse shining from the edge of our universe. Astronomers have discovered it using the European Space Agency's orbiting gamma-ray observatory, Integral. Now, they must work hard to understand it.

The object, known only by its catalogue name IGR J22517+2218, was discovered this year, but its nature was unknown. This is not an unusual situation. Around 30% of the sources discovered by Integral remain unidentified so far. All astronomers know for certain, is that there are celestial sources out there, pumping gamma rays into space. However, the identification of the sources with individual celestial objects will have to wait for more detailed observations in other wavelengths.

In fact, this was the case for IGR J22517+2218. It came as a surprise when NASA's Swift satellite recorded the object in X-rays, giving its position within much more precision than can be achieved in gamma-rays. IGR J22517+2218 was identified with the already known active galaxy MG3 J225155+2217. This galaxy is so distant that it is the furthest celestial object ever to be recorded by Integral.

All active galaxies are powered by supermassive black holes. These celestial monsters contain between a million and several thousand million times the mass of the Sun.

They generate a gravitational field so large that they swallow any matter passing nearby, releasing enormous amounts of energy in the process. In the case of IGR J22517+2218, the Integral observations show that it is a gargantuan powerhouse, throwing out stupendous quantities of gamma rays.

"It is gobbling up an entire solar system every few days and hurling the energy out in gamma-rays," says Loredana Bassani, IASF-Bologna/INAF, Italy, who together with colleagues has investigated this distant galaxy.

The Integral observations show that the galaxy is one of a special kind of active galaxy, known as a blazar. These are the most energetic of the active galaxies. However, the Integral data does show some curiosities.

"This is a very peculiar object. We have been able to classify it as a blazar but it has some strange characteristics," says Bassani.

Blazars tend to have two major peaks of emission. In objects similar to IGR J22517+2218, one peak occurs in infrared wavelengths and is produced by the radiation given off by electrons spiralling around the magnetic field lines. The other peak occurs at high-energy gamma-ray wavelengths and is produced by those same electrons colliding with photons of light.

In the case of IGR J22517+2218, the object appears to have only one peak. This occurs in neither of the conventional wavelength ranges but, in fact, in the low-energy gamma-ray band instead. Either the infrared peak has been moved up in energy, or the high-energy gamma-ray peak has been moved down.

Either way, when the team can work out what this means, it will doubtlessly tell them a lot about active galaxies, and blazars in particular. "Whatever we discover, this object will stretch our understanding of the blazars," says Bassani.

The team hope to continue observing this object at all wavelengths in an effort to build up a full picture of the radiation given out by this celestial object. In this way, they will be able to piece together the manner in which the supermassive black hole at the heart of IGR J22517+2218 is devouring its surroundings.   


Source: SPACEFLIGHTNOW.COM
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 24/10/2007 22:27:43
Patients should ask surgeons about using honey to heal wounds

Surgeons are being advised to consider the supermarket as well as the drugs cupboard when it comes to effective wound healing, according to a research review published in the October issue of IJCP, the International Journal of Clinical Practice.

And patients who’ve undergone surgery should ask their doctors whether they should apply honey to their wounds to speed up healing and reduce infection.

“Honey is one of the oldest foods in existence and was an ancient remedy for wound healing” explains lead author Dr Fasal Rauf Khan from North West Wales NHS Trust in Bangor. “It was found in the tomb of King Tutankhamun and was still edible as it never spoils.”

Honey is enjoying a revival as more reports of its effectiveness are published, he adds.

“Researchers started to document the wound healing properties of honey in the early 20th century, but the introduction of antibiotics in 1940 temporarily halted its use.

“Now concerns about antibiotic resistance, and a renewed interest in natural remedies, has prompted a resurgence in the antimicrobial and wound healing properties of honey.

“Honey has a number of properties that make it effective against bacterial growth, including its high sugar content, low moisture content, gluconic acid – which creates an acidic environment – and hydrogen peroxide. It has also been shown to reduce inflammation and swelling.”

Researchers have also reported that applying honey can be used to reduce amputation rates among diabetes patients.

Stressing that patients should always check with their surgeon before applying any substance to post-operative wounds, Dr Khan adds that studies have found that honey offers a number of benefits.

“It can be used to sterilise infected wounds, speed up healing and impede tumours, particularly in keyhole surgery.”

Studies have suggested that honey should be applied at regular intervals, from hourly to twice daily and that wounds can become sterile in three to 10 days.

“The research suggests that honey seems to be especially indicated when wounds become infected or fail to close or heal” says Dr Khan. “It is probably even more useful for healing the wounds left by laparoscopic surgery to remove cancers.”

18 studies covering more than 60 years were included in the review. The authors also looked at other substances used for wound healing, including maggots, which were also commonly used before the introduction of antibiotics and are enjoying a revival.

The team also discovered an ancient manuscript that used wine dregs, juniper prunes and beer, but point out that that has not been tried and tested in recent years!

“Our research suggests that surgeons should seriously consider using honey for post-operative wounds and offer this to patients” concludes Dr Khan. “We would also encourage patients to ask about honey as an option, but stress that they should always follow their surgeon’s advice and not try any home remedies.”

SOURCE: EUREKALERT.ORG
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 24/10/2007 22:35:13
Dwarf galaxies need dark matter too, U-M astronomers say

ANN ARBOR, Mich.—Stars in dwarf spheroidal galaxies behave in a way that suggests the galaxies are utterly dominated by dark matter, University of Michigan astronomers have found.

Astronomy professor Mario Mateo and post-doctoral researcher Matthew Walker measured the velocity of 6,804 stars in seven dwarf satellite galaxies of the Milky Way: Carina, Draco, Fornax, Leo I, Leo II, Sculptor and Sextans. They found that, contrary to what Newton's law of gravity predicts, stars in these galaxies do not move slower the farther they are from their galaxy's core.

"These galaxies show a problem right from the center," Mateo said. "The velocity doesn't get smaller. It just stays the same, which is eerie."

Astronomers already know stars in spiral galaxies behave in a similar way. This research dramatically increases the available information about smaller galaxies, making it possible to confirm that the distribution of light and stars in them is not the same as the distribution of mass.

"We have more than doubled the amount of data having to do with these galaxies, and that allows us to study them in an unprecedented manner. Our research shows that dwarf galaxies are utterly dominated by dark matter, so long as Newtonian gravity adequately describes these systems," Walker said. Walker received his doctorate from U-M earlier this year and currently has a post-doctoral position at the University of Cambridge in the United Kingdom.

Dark matter is a substance astronomers have not directly observed, but they deduce it exists because they detect its gravitational effects on visible matter. Based on these measurements, the prevailing theory in astronomy and cosmology is that the visible parts of the universe make up only a fraction of its total matter and energy.

The planet Neptune was once "dark matter," Mateo said. Before the term was even coined, astronomers predicted its existence based on an anomaly in the orbit of Neptune's neighbor Uranus. They knew just where to look for Neptune.

For the past quarter century, astronomers have been looking for the Neptune of the universe, so to speak. Dark matter could take the form of dwarf stars and planets, elementary particles including neutrinos, or hypothetical and as-yet undetected particles that don't interact with visible light or other parts of the electromagnetic spectrum.

Dark matter is believed to hold galaxies together. The gravitational force of the visible matter is not considered strong enough to prevent stars from escaping. Other theories exist to explain these discrepancies, though. For example, Modified Newtonian Dynamics, Mateo said, proposes that gravitational forces become stronger when accelerations are very weak. While their results align with current dark matter models, Mateo and Walker say they also bolster this less-popular explanation.

"These dwarf galaxies are not much to look at," Mateo continued, "but they may really alter our fundamental views on the nature of dark matter and, perhaps, even gravity."

Walker will present a paper on these findings on Oct. 30 at the Magellan Science Meeting in Cambridge, Mass. The paper he will present is Velocity Dispersion Profiles of Seven Dwarf Spheroidal Galaxies. It was published in the Sept. 20 edition of Astrophysical Journal Letters.

SOURCE: University of Michigan News Service http://www.ns.umich.edu
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 11/11/2007 13:10:08
Scientist brings 50 million year old spider 'back to life'

A 50-million-year-old fossilised spider has been brought back to life in stunning 3D by a scientist at The University of Manchester.

In a paper published in the latest issue of the Zootaxa journal, Dr David Penney and co-authors from Ghent University in Belgium report on the use of a technique called ‘Very High Resolution X-Ray Computed Tomography’ (VHR-CT) to ‘digitally dissect’ tiny fossils and reveal the preservation of internal organs.

Dr Penney, from The School of Earth, Atmospheric and Environmental Sciences (SEAES), specialises in studying spiders trapped and preserved in amber tens of millions of years ago.

The male spider studied in his latest paper is a new species named Cenotextricella simoni. It is around 53-million years old and was found preserved in amber in an area of France known as the Paris Basin.

This is the first time the VHR-CT technique has been used to digitally dissect a fossil in amber – and Dr Penney says it has the potential to ‘revolutionise’ their study.

The VHR-CT technique was originally developed for medical diagnostic purposes.

Dr Penney said: “This technique essentially generates full 3D reconstructions of minute fossils and permits digital dissection of the specimen to reveal the preservation of internal organs.

“Up until recently the only place to do such scans was at The University of Texas, although they never achieved results like these.

“My colleagues in the department of Subatomic and Radiation Physics at Ghent University in Belgium have significantly increased the resolution of the technology, bringing some quite amazing results.

“This is definitely the way forward for the study of amber fossils.

“Amber provides a unique window into past forest ecosystems. It retains an incredible amount of information, not just about the spiders themselves, but also about the environment in which they lived.”

Dr Penney is currently spending an indefinite period in the African jungle in a ‘living laboratory' studying spiders.

Earlier this year, a species of spider which dates back more than 20 million years was named after Dr Penney. The amber-encased spider which was discovered deep in a Mexican mine is thought to have lived long before the first humans.

It was found by a Mexican researcher who earned the right to name the species and he chose the name ‘Episinus penneyi’ in honour of his former colleague.

SOURCE: www.eurekalert.org

Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 19/11/2007 18:47:43
A new window on the universe
UWM physicists involved in international project to scour space for gravitational waves

UWM physicists who are working on the international LIGO project are (clockwise from left) Xavier Siemens, Alan Wiseman, Patrick Brady and Jolien Creighton. All four faculty members came to UWM...
Click here for more information.

Using new tools to look at the universe, says Patrick Brady, often has led to discoveries that change the course of science. History is full of examples.

“Galileo was the first person to use the telescope to view the cosmos,” says Brady, a UWM professor of physics. “His observations with the new technology led to the discovery of moons orbiting Jupiter and lent support to the heliocentric model of the solar system.”

Just such an opportunity exists today with a unique observatory that is scanning the skies, searching for one of Einstein’s greatest predictions – gravitational waves.

Gravitational waves are produced when massive objects in space move violently. The waves carry the imprint of the events that cause them. Scientists already have indirect evidence that gravitational waves exist, but have not directly detected them.

UWM researchers, backed by considerable funding from the National Science Foundation, are taking a leadership role in the quest.

It is an epic undertaking involving about 500 scientists worldwide, including Brady and other members of UWM’s Center for Cosmology and Gravitation: associate professors Alan Wiseman and Jolien Creighton, and assistant professor Xavier Siemens.

Two UWM adjunct physicists, who work at the Max Planck Institute in Germany, also are involved – former UWM professor Bruce Allen and scientist Maria Alessandra Papa.

“It’s an unimaginable opportunity to be on the forefront of scientific discovery,” says Creighton.

The Laser Interferometer Gravitational-wave Observatory, or LIGO, consists of detectors at two U.S. sites managed by the California Institute of Technology (Caltech) and Massachusetts Institute of Technology (MIT).

UWM’s physicists are analyzing the data generated by the LIGO facilities.

The project is supported with a sizable investment of grant money from both federal and UWM sources.

Last year, UWM’s LIGO group brought in $3 million in grant funding. Since 1999, UWM has received more than $9 million for the project, with much of it going toward a supercomputer called Nemo that operates unobtrusively on the second floor of the Physics Building.

Stretching and squeezing

The LIGO observatories use lasers to accurately monitor the distance between a central station and mirrors suspended three miles away along perpendicular arms. When a gravitational wave, a traveling ripple in space-time, passes by, the mirror in one arm will move closer to the central station, while the other mirror will move away.

The change in distance caused by stretching and squeezing is what LIGO is designed to measure, says Wiseman.

Those changes will be inconceivably tiny. LIGO can record distortions at a scale so small, it is comparable in distance to a thousandth of the size of an atomic nucleus.

LIGO records a series of numbers – lots of them – and feeds them to several supercomputer clusters around the country, including UWM’s Nemo cluster.

Think of a modern hard disk on a desktop computer, which stores about 100 gigabytes. LIGO fills up about 10 of those at Nemo in a single day, says Brady.

The computer’s job is to sort out the numerical patterns representing gravitational waves buried in ambient noise produced by lots of other vibrations – from internal vibrations of the equipment itself, to magnetic fluctuations from lightning storms, to seismic vibrations from trains rolling along the tracks a few miles from the observatory, or from earthquakes on the other side of the world.

“There are thousands or even millions of different signals that could be emitted from space,” says Wiseman. “So you have to take each segment of data individually. That turns out to be a formidable computational problem.”

Nemo performs many billions of calculations per second in its search for these signals.

Space sounds


The strings of numbers from LIGO are like tracks on a compact disk, says Brady. That means, once detected, gravitational-wave signals can be converted into sound.

In fact, scientists have already simulated, based on mathematical predictions, what certain events in space will sound like.

When two black holes are merging, for example, you might expect to hear a “chirp” that represents the spiraling together of the black holes just before they collide. “The spiral can go on for tens of thousands of years,” says Brady. “The sound is the identifying signal of the last few seconds of the process!”

Those analyzing the data from space could actually listen to the data. Instead, scientists look for the signals using computers like Nemo.

To augment the computing capacity, UWM is hosting a way for anyone with a computer and a high-speed Internet connection to join the astrophysical treasure hunt. Called “Einstein@Home, the program borrows computer power available when participants are not using it, and pool those resources to aid in filtering the massive amounts of data from LIGO.

Possible secrets


Scientists concede that the current LIGO facilities will need to be improved to increase the chances of detecting gravitational waves. More NSF funding to do that is requested in the 2009 U.S. budget currently winding its way through the approval process.

For now, the best hope is to detect events relatively close to Earth.

So what is the likelihood of success"

“The events we are looking for may only happen once every million years in our galaxy,” says Wiseman, “but if your instrument is sensitive enough to see such events in, say, one million galaxies, then the probability of detecting something is much larger.”

Gravitational waves may hold secrets to the nature of black holes, the unknown properties of nuclear material, and maybe even how the universe began.

“We’ve only been able to find out about the universe since it became cool,” says Siemens. “But with gravitational waves, we’ll see the universe when it was much younger – and hotter.”

But then again, scientists don’t really know.

“I think we’re in for a surprise,” says Siemens. “We have all these ideas about what we think we will find, but it could be something completely different.”
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 14/12/2007 13:59:03
Saturn's rings may be old as solar system, Cassini shows
UNIVERSITY OF COLORADO NEWS RELEASE
Posted: December 12, 2007

New observations by NASA's Cassini spacecraft indicate the rings of Saturn, once thought to have formed during the age of the dinosaurs, instead may have been created roughly 4.5 billion years ago when the solar system was still under construction.



 
Professor Larry Esposito, principal investigator for Cassini's Ultraviolet Imaging Spectrograph at CU-Boulder, said data from NASA's Voyager spacecraft in the 1970s and later NASA's Hubble Space Telescope had led scientists to believe Saturn's rings were relatively youthful and likely created by a comet that shattered a large moon, perhaps 100 million years ago.

But ring features seen by instruments on Cassini -- which arrived at Saturn in 2004 -- indicate the rings were not formed by a single cataclysmic event, he said. The ages of the different rings appear to vary significantly and the ring material is continually being recycled, Esposito said.

"The evidence is consistent with the picture that Saturn has had rings all through its history," said Esposito of CU-Boulder's Laboratory for Atmospheric and Space Physics. "We see extensive, rapid recycling of ring material, in which moons are continually shattered into ring particles, which then gather together and re-form moons."

Esposito and CU-Boulder colleague Miodrag Sremcevic presented their findings today in a news briefing at the fall meeting of the American Geophysical Union held Dec. 10 to Dec. 14 in San Francisco.

"We have discovered that the rings were probably not created just yesterday in cosmic time, and in this scenario it is not just luck that we are seeing planetary rings now," said Esposito. "They probably were always around but continually changing, and they will be around for many billions of years."

Scientists had previously believed rings as old as Saturn itself should be darker due to ongoing pollution by the "infall" of meteoric dust, leaving telltale spectral signatures, Esposito said. But the new Cassini observations indicate the churning mass of ice and rock within Saturn's gigantic ring system is likely much larger than previously estimated, helping to explain why the rings appear relatively bright to ground-based telescopes and spacecraft.

"The more mass there is in the rings, the more raw material there is for recycling, which essentially spreads this cosmic pollution around," he said. "If this pollution is being shared by a much larger volume of ring material, it becomes diluted and helps explain why the rings appear brighter and more pristine than we would have expected."

Esposito, who discovered Saturn's faint F ring in 1979 using data from NASA's Pioneer 11 spacecraft, said an upcoming paper by him and colleagues in the journal Icarus supports the theory that Saturn's ring material is being continually recycled. Observing the flickering of starlight passing through the rings in a process known as stellar occultation, the researchers discovered 13 objects in the F ring ranging in size from 30 yards to six miles across.

Since most of the objects were translucent -- indicating at least some starlight was passing through them -- the researchers concluded they probably are temporary clumps of icy boulders that are continually collecting and disbanding due to the competing processes of shattering and coming together again. The team tagged the clumpy moonlets with cat names like "Mittens" and "Fluffy" because they appear to come and go unexpectedly over time and have multiple lives, said Esposito.

Esposito stressed that in the future Saturn's rings won't be the same we see today, likening them to great cities around the world like San Francisco, Berlin or Beijing. "While the cities themselves will go on for centuries or millennia, the faces of people on the streets will always be changing due to continual birth and aging of new citizens."

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate in Washington, D.C.

SOURCE: SPACFLIGHTNOW.ORG
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 14/12/2007 14:13:31
Are humans evolving faster?

Findings suggest we are becoming more different, not alike
Researchers discovered genetic evidence that human evolution is speeding up – and has not halted or proceeded at a constant rate, as had been thought – indicating that humans on different continents are becoming increasingly different.

“We used a new genomic technology to show that humans are evolving rapidly, and that the pace of change has accelerated a lot in the last 40,000 years, especially since the end of the Ice Age roughly 10,000 years ago,” says research team leader Henry Harpending, a distinguished professor of anthropology at the University of Utah.

Harpending says there are provocative implications from the study, published online Monday, Dec. 10 in the journal Proceedings of the National Academy of Sciences:

-- “We aren’t the same as people even 1,000 or 2,000 years ago,” he says, which may explain, for example, part of the difference between Viking invaders and their peaceful Swedish descendants. “The dogma has been these are cultural fluctuations, but almost any temperament trait you look at is under strong genetic influence.”

-- “Human races are evolving away from each other,” Harpending says. “Genes are evolving fast in Europe, Asia and Africa, but almost all of these are unique to their continent of origin. We are getting less alike, not merging into a single, mixed humanity.” He says that is happening because humans dispersed from Africa to other regions 40,000 years ago, “and there has not been much flow of genes between the regions since then.”

“Our study denies the widely held assumption or belief that modern humans [those who widely adopted advanced tools and art] appeared 40,000 years ago, have not changed since and that we are all pretty much the same. We show that humans are changing relatively rapidly on a scale of centuries to millennia, and that these changes are different in different continental groups.”

The increase in human population from millions to billions in the last 10,000 years accelerated the rate of evolution because “we were in new environments to which we needed to adapt,” Harpending adds. “And with a larger population, more mutations occurred.”

Study co-author Gregory M. Cochran says: “History looks more and more like a science fiction novel in which mutants repeatedly arose and displaced normal humans – sometimes quietly, by surviving starvation and disease better, sometimes as a conquering horde. And we are those mutants.”

Harpending conducted the study with Cochran, a New Mexico physicist, self-taught evolutionary biologist and adjunct professor of anthropology at the University of Utah; anthropologist John Hawks, a former Utah postdoctoral researcher now at the University of Wisconsin, Madison; geneticist Eric Wang of Affymetrix, Inc. in Santa Clara, Calif.; and biochemist Robert Moyzis of the University of California, Irvine.

No Justification for Discrimination

The new study comes from two of the same University of Utah scientists – Harpending and Cochran – who created a stir in 2005 when they published a study arguing that above-average intelligence in Ashkenazi Jews – those of northern European heritage – resulted from natural selection in medieval Europe, where they were pressured into jobs as financiers, traders, managers and tax collectors. Those who were smarter succeeded, grew wealthy and had bigger families to pass on their genes. Yet that intelligence also is linked to genetic diseases such as Tay-Sachs and Gaucher in Jews.

That study and others dealing with genetic differences among humans – whose DNA is more than 99 percent identical – generated fears such research will undermine the principle of human equality and justify racism and discrimination. Other critics question the quality of the science and argue culture plays a bigger role than genetics.

Harpending says genetic differences among different human populations “cannot be used to justify discrimination. Rights in the Constitution aren’t predicated on utter equality. People have rights and should have opportunities whatever their group.”

Analyzing SNPs of Evolutionary Acceleration

The study looked for genetic evidence of natural selection – the evolution of favorable gene mutations – during the past 80,000 years by analyzing DNA from 270 individuals in the International HapMap Project, an effort to identify variations in human genes that cause disease and can serve as targets for new medicines.

The new study looked specifically at genetic variations called “single nucleotide polymorphisms,” or SNPs (pronounced “snips”) which are single-point mutations in chromosomes that are spreading through a significant proportion of the population.

Imagine walking along two chromosomes – the same chromosome from two different people. Chromosomes are made of DNA, a twisting, ladder-like structure in which each rung is made of a “base pair” of amino acids, either G-C or A-T. Harpending says that about every 1,000 base pairs, there will be a difference between the two chromosomes. That is known as a SNP.

Data examined in the study included 3.9 million SNPs from the 270 people in four populations: Han Chinese, Japanese, Africa’s Yoruba tribe and northern Europeans, represented largely by data from Utah Mormons, says Harpending.

Over time, chromosomes randomly break and recombine to create new versions or variants of the chromosome. “If a favorable mutation appears, then the number of copies of that chromosome will increase rapidly” in the population because people with the mutation are more likely to survive and reproduce, Harpending says.

“And if it increases rapidly, it becomes common in the population in a short time,” he adds.

The researchers took advantage of that to determine if genes on chromosomes had evolved recently. Humans have 23 pairs of chromosomes, with each parent providing one copy of each of the 23. If the same chromosome from numerous people has a segment with an identical pattern of SNPs, that indicates that segment of the chromosome has not broken up and recombined recently.

That means a gene on that segment of chromosome must have evolved recently and fast; if it had evolved long ago, the chromosome would have broken and recombined.

Harpending and colleagues used a computer to scan the data for chromosome segments that had identical SNP patterns and thus had not broken and recombined, meaning they evolved recently. They also calculated how recently the genes evolved.

A key finding: 7 percent of human genes are undergoing rapid, recent evolution.

The researchers built a case that human evolution has accelerated by comparing genetic data with what the data should look like if human evolution had been constant:


The study found much more genetic diversity in the SNPs than would be expected if human evolution had remained constant.


If the rate at which new genes evolve in Africans was extrapolated back to 6 million years ago when humans and chimpanzees diverged, the genetic difference between modern chimps and humans would be 160 times greater than it really is. So the evolution rate of Africans represents a recent speedup in evolution.


If evolution had been fast and constant for a long time, there should be many recently evolved genes that have spread to everyone. Yet, the study revealed many genes still becoming more frequent in the population, indicating a recent evolutionary speedup.

Next, the researchers examined the history of human population size on each continent. They found that mutation patterns seen in the genome data were consistent with the hypothesis that evolution is faster in larger populations.

Evolutionary Change and Human History: Got Milk?

“Rapid population growth has been coupled with vast changes in cultures and ecology, creating new opportunities for adaptation,” the study says. “The past 10,000 years have seen rapid skeletal and dental evolution in human populations, as well as the appearance of many new genetic responses to diet and disease.”

The researchers note that human migrations into new Eurasian environments created selective pressures favoring less skin pigmentation (so more sunlight could be absorbed by skin to make vitamin D), adaptation to cold weather and dietary changes.

Because human population grew from several million at the end of the Ice Age to 6 billion now, more favored new genes have emerged and evolution has speeded up, both globally and among continental groups of people, Harpending says.

"We have to understand genetic change in order to understand history,” he adds.

For example, in China and most of Africa, few people can digest fresh milk into adulthood. Yet in Sweden and Denmark, the gene that makes the milk-digesting enzyme lactase remains active, so “almost everyone can drink fresh milk,” explaining why dairying is more common in Europe than in the Mediterranean and Africa, Harpending says.

He now is studying if the mutation that allowed lactose tolerance spurred some of history’s great population expansions, including when speakers of Indo-European languages settled all the way from northwest India and central Asia through Persia and across Europe 4,000 to 5,000 years ago. He suspects milk drinking gave lactose-tolerant Indo-European speakers more energy, allowing them to conquer a large area.

But Harpending believes the speedup in human evolution “is a temporary state of affairs because of our new environments since the dispersal of modern humans 40,000 years ago and especially since the invention of agriculture 12,000 years ago. That changed our diet and changed our social systems. If you suddenly take hunter-gatherers and give them a diet of corn, they frequently get diabetes. We’re still adapting to that. Several new genes we see spreading through the population are involved with helping us prosper with high-carbohydrate diet.”





SOURCE : University of Utah Public Relations

www.unews.utah.edu

Via EUYREALERT.ORG





Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 10/01/2008 20:02:07
Red dust in disk may harbor precursors to life
CARNEGIE INSTITUTION NEWS RELEASE
Posted: January 5, 2008

WASHINGTON, DC - Astronomers at the Carnegie Institution have found the first indications of highly complex organic molecules in the disk of red dust surrounding a distant star. The eight-million-year-old star, known as HR 4796A, is inferred to be in the late stages of planet formation, suggesting that the basic building blocks of life may be common in planetary systems.

In a study published in the current Astrophysical Journal Letters, John Debes and Alycia Weinberger of the Carnegie Institution's Department of Terrestrial Magnetism with Glenn Schneider of the University of Arizona report observations of infrared light from HR 4796A using the Near-Infrared Multi-Object Spectrometer aboard the Hubble Space Telescope. The researchers found that the spectrum of visible and infrared light scattered by the star's dust disk looks very red, the color produced by large organic carbon molecules called tholins. The spectrum does not match those of other red substances, such as iron oxide.

Tholins do not form naturally on present-day Earth because oxygen in the atmosphere would quickly destroy them, but they are hypothesized to have existed on the primitive Earth billions of years ago and may have been precursors to the biomolecules that make up living organisms. Tholins have been detected elsewhere in the solar system, such as in comets and on Saturn's moon Titan, where they give the atmosphere a red tinge. This study is the first report of tholins outside the solar system.

"Until recently it's been hard to know what makes up the dust in a disk from scattered light, so to find tholins this way represents a great leap in our understanding," says Debes.

HR 4796A is located in the constellation Centaurus, visible primarily form the southern hemisphere. It is about 220 light years from Earth. The discovery of its dust disk in 1991 generated excitement among astronomers, who consider it a prime example of a planetary system caught in the act of formation. The dust is generated by collisions of small bodies, perhaps similar to the comets or asteroids in our solar system, and which may be coated by the organics. These planetesimals can deliver these building blocks for life to any planets that may also be circling the star.

"Astronomers are just beginning to look for planets around stars much different from the Sun. HR 4796A is twice as massive, nearly twice as hot as the sun, and twenty times more luminous than the Sun," says Debes. "Studying this system provides new clues to understanding the different conditions under which planets form and, perhaps, life can evolve."

This research is based on observations with the NASA/ESA Hubble Space Telescope and was supported by NASA and the NASA Astrobiology Institute.

The Carnegie Institution has been a pioneering force in basic scientific research since 1902. It is a private, nonprofit organization with six research departments throughout the U.S. Carnegie scientists are leaders in plant biology, developmental biology, astronomy, materials science, global ecology, and Earth and planetary science.

SOURCE:SPACEFLIGHTNOW.ORG
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 15/02/2008 14:42:52
X-rays betray giant particle accelerator in the sky
EUROPEAN SPACE AGENCY NEWS RELEASE


ESA's orbiting gamma-ray observatory, Integral, has made the first unambiguous discovery of highly energetic X-rays coming from a galaxy cluster. The find has shown the cluster to be a giant particle accelerator. 

The Ophiuchus galaxy cluster is one of brightest in the sky at X-ray wavelengths. The X-rays detected are too energetic to originate from quiescent hot gas inside the cluster and suggest instead that giant shockwaves must be rippling through the gas. This has turned the galaxy cluster into a giant particle accelerator.

Most of the X-rays come from hot gas in the cluster, which in the case of Ophiuchus is extremely hot, at 100 million degrees Kelvin. Four years ago, data from the Italian/ Dutch BeppoSAX satellite showed a possible extra component of high-energy X-rays in a different cluster, the Coma cluster.

"Two groups analysed the data. One group saw the component but the other did not," says Dominique Eckert, Integral Science Data Centre (ISDC), University of Geneva, Switzerland. So Eckert and colleagues from ISDC launched an investigation into the mystery.

They turned to Integral and its five-year, all-sky survey and found that ESA's orbiting gamma-ray observatory did show an unambiguous detection of highly energetic X-rays, coming from the Ophiuchus cluster of galaxies. These X-rays can be produced in two ways, both of which involve high-energy electrons.

The first option is that the electrons are caught in the magnetic field threading through the cluster. In this case, the electrons would spiral around the magnetic field lines, releasing synchrotron radiation in the form of X-rays.

The electrons would be extremely energetic, carrying over 100 000 times the energy of the electrons in the alternative scenario, which is that the electrons are perhaps colliding with microwaves left over from the origin of the Universe and now bathe all of space. In such collisions, the electrons lose some energy, emitted as X-rays.

Determining which of these scenarios is correct is the next job for the team. They plan to use radio telescopes to measure the magnetic field of the galaxy cluster. They also plan to use the High Energy Stereoscopic System (HESS) in Namibia. This giant telescope looks for the brief flash of light generated when highly energetic gamma rays collide with particles in Earth's atmosphere. If HESS sees such flashes coming from Ophiuchus, then the astronomers will know that the synchrotron scenario is correct.

Either way, the electrons themselves are most likely to be accelerated to high energies by shockwaves travelling through the cluster gas. The shockwaves are set up when two clusters collide and merge. The question is how recently Ophiuchus swallowed its companion cluster.

In the synchrotron scenario, the highly energetic electrons cool very quickly. If the team find this to be the case, then the collision must still be in progress. In the case of microwave scattering, cooling takes a long time and the collision could have taken place at any time in the past.

Once the scientists know, they will be able to properly understand the history of the cluster. One thing is already certain; nature has transformed the galaxy cluster into a powerful particle accelerator, perhaps 20 times more powerful than CERN's Large Hadron Collider (LHC), which begins operation in Switzerland this summer.

"Of course the Ophiuchus cluster is somewhat bigger," says Stephane Paltani, a member of the ISDC team. While LHC is 27 km across, the Ophiuchus galaxy cluster is over two million light-years in diameter."   
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 21/03/2008 12:59:51
Good luck indeed: 53 million-year-old rabbit's foot bones found

One day last spring, fossil hunter and anatomy professor Kenneth Rose, Ph.D. was displaying the bones of a jackrabbit’s foot as part of a seminar at the Johns Hopkins University School of Medicine when something about the shape of the bones looked oddly familiar.

That unanticipated eureka moment has led researchers at the school to the discovery of the oldest known record of rabbits. The fossil evidence in hand, found in west-central India, predates the oldest previously known rabbits by several million years and extends the record of the whole category of the animal on the Indian subcontinent by 35 million years.

Published online in the February Proceedings of the Royal Society, the investigators say previous fossil and molecular data suggested that rabbits and hares diverged about 35 million years ago from pikas, a mousy looking member of the family Ochotonidae in the order of lagomorphs, which also includes all of the family Leporidae encompassing rabbits and hares.

But the team led by Johns Hopkins’s Rose found that their rabbit bones were very similar in characteristics to previously unreported Chinese rabbit fossils that date to the Middle Eocene epoch, about 48 million years ago. The Indian fossils, dating from about 53 million years ago, appear to show advanced rabbit-like features, according to Rose.

“What we have suggests that diversification among the Lagamorpha group-all modern day hares, rabbits and pikas-may already have started by the Early Eocene,” says Rose, professor in the Center for Functional Anatomy and Evolution at the Johns Hopkins University School of Medicine.

Rose says the new discovery was delayed a few years because the researchers had not been looking specifically to determine the age of rabbits. “We found these bones on a dig in India a few years ago and didn’t know what animal they came from, so we held onto them and figured we’d look at them later,” he says. “It didn’t occur to us they would be rabbits because there were no known rabbits that early in time and the only known rabbits from that part of the world are from central Asia.”

But one day, while using the jackrabbit foot bones as a teaching tool for a class, the shape of the bones in the class struck him as something he’d seen before among his collection of unidentified bones.

Sure enough, the tiny bones about a quarter of an inch long from India looked remarkably similar to ankle and foot bones from modern day jackrabbits, which are 4 to 5 times bigger.

Rose and his team set out and measured every dimension of their Indian bones and compared them to eight living species of rabbits and hares. They also compared them to two species of the related pika-that mouse-like, mountain-dwelling critter that lives in the Rocky Mountains of North America, among other places.

Using a technique called character analysis, the team first recorded measurements of 20 anatomical features of the bones, which showed that the bones are definitely Lagomorph and closer to rabbits than pikas. The scientists then ran a series of statistical tests on the individual measurements to see how they compared with the Chinese fossils as well as living rabbits and pikas. They found that although the Indian fossils resemble pikas in some primitive features, they look more like rabbits in specialized bone features.

Asked how many years of good luck one gets with a 53 million-year-old rabbit foot bone, Rose quipped that he “already got lucky with the feet, but what we really would like are some teeth that tell how different these animals really were.”


SOURCE: EUREKALERT.ORG
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 21/03/2008 13:06:27
Rare cosmic rays are from far away
Study confirms 1966 prediction: The most energetic particles in the universe are not from the neighborhood

Final results from the University of Utah’s High-Resolution Fly’s Eye cosmic ray observatory show that the most energetic particles in the universe rarely reach Earth at full strength because they come from great distances, so most of them collide with radiation left over from the birth of the universe.

The findings are based on nine years of observations at the now-shuttered observatory on the U.S. Army’s Dugway Proving Ground. They confirm a 42-year-old prediction – known as the Greisen-Zatsepin-Kuzmin (GZK) “cutoff,” “limit” or “suppression” – about the behavior of ultrahigh-energy cosmic rays, which carry more energy than any other known particle.

The idea is that most – but not all – cosmic ray particles with energies above the GZK cutoff cannot reach Earth because they lose energy when they collide with “cosmic microwave background radiation,” which was discovered in 1965 and is the “afterglow” of the “big bang” physicists believe formed the universe 13 billion years ago.

The journal Physical Review Letters published the results Friday, March 21.

The GZK limit’s existence was first predicted by Kenneth Greisen of Cornell University while visiting the University of Utah in 1966, and independently by Georgiy Zatsepin and Vadim Kuzmin of Moscow’s Lebedev Institute of Physics.

“It has been the goal of much of ultrahigh-energy cosmic ray physics for the past 40 years to find this cutoff or disprove it,” says physics Professor Pierre Sokolsky, dean of the University of Utah College of Science and leader of the study by a collaboration of 60 scientists from seven research institutions. “For the first time in 40 years, that question is answered: there is a cutoff.”

That conclusion, based on 1997-early 2006 observations at the High Resolution Fly’s Eye cosmic ray observatory (nicknamed HiRes) in Utah’s western desert, has been bolstered by the new Auger cosmic ray observatory in Argentina. During a cosmic ray conference in Merida, Mexico, last summer, Auger physicists outlined preliminary, unpublished results showing that the number of ultrahigh-energy cosmic rays reaching Earth drops sharply above the cutoff.

So both the HiRes and Auger findings contradict Japan’s now-defunct Akeno Giant Air Shower Array (AGASA), which observed roughly 10 times more of the highest-energy cosmic rays – and thus suggested there was no GZK cutoff.

Cosmic Rays: Far Out

Last November, the Auger observatory collaboration – to which Sokolsky also belongs – published a study suggesting that the highest-energy cosmic rays come from active galactic nuclei or AGNs, or the hearts of extremely active galaxies believed to harbor supermassive black holes.

AGNs are distributed throughout the universe, so confirmation that the GZK cutoff is real suggests that if ultrahigh-energy cosmic rays are spewed out by AGNs, they primarily are very distant from the Earth – at least in Northern Hemisphere skies viewed by the HiRes observatory. University of Utah physics Professor Charlie Jui, a co-author of the new study, says that means galaxies beyond our “local” supercluster of galaxies at distances of at least 150 million light years from Earth, or roughly 870 billion billion miles. [In U.S. usage, billion billion is correct here and in subsequent references for 10 to the 18th power. In British usage, 10 to the 18th power should be million billion.]

However, unpublished results from HiRes do not find the same correlation that Auger did between ultrahigh-energy cosmic rays and active galactic nuclei. So there still is uncertainty about the true source of extremely energetic cosmic rays.

“We still don’t know where they’re coming from, but they’re coming from far away,” Sokolsky says. “Now that we know the GZK cutoff is there, we have to look at sources much farther out.”

In addition to the University of Utah, High Resolution Fly’s Eye scientists are from Los Alamos National Laboratory in New Mexico, Columbia University in New York, Rutgers University – the State University of New Jersey, Montana State University in Bozeman, the University of Tokyo and the University of New Mexico, Albuquerque.

Messengers from the Great Beyond

Cosmic rays, discovered in 1912, are subatomic particles: the nuclei of mostly hydrogen (bare protons) and helium, but also of some heavier elements such as oxygen, carbon, nitrogen or even iron. The sun and other stars emit relatively low-energy cosmic rays, while medium-energy cosmic rays come from exploding stars.

The source of ultrahigh-energy cosmic rays has been a mystery for almost a century. The recent Auger observatory results have given the edge to the popular theory they originate from active galactic nuclei. They are 100 million times more energetic than anything produced by particle smashers on Earth. The energy of one such subatomic particle has been compared with that of a lead brick dropped on a foot or a fast-pitched baseball hitting the head.

“Quite apart from arcane physics, we are talking about understanding the origin of the most energetic particles produced by the most energetic acceleration process in the universe,” Sokolsky says. “It’s a question of how much energy the universe can pack into these extraordinarily tiny particles known as cosmic rays. … How high the energy can be in principle is unknown. By the time they get to us, they have lost that energy.”

He adds: “Looking at energy processes at the very edge of what’s possible in the universe is going to tell us how well we understand nature.”

Ultrahigh-energy cosmic rays are considered to be those above about 1 billion billion electron volts (1 times 10 to the 18th power).

The most energetic cosmic ray ever found was detected over Utah in 1991 and carried an energy of 300 billion billion electron volts (3 times 10 to the 20th power). It was detected by the University of Utah’s original Fly’s Eye observatory, which was built at Dugway during 1980-1981 and improved in 1986. A better observatory was constructed during 1994-1999 and named the High Resolution Fly’s Eye.

Jui says that during its years of operation, HiRes detected only four of the highest-energy cosmic rays – those with energies above 100 billion billion electron volts. AGASA detected 11, even though it was only one-fourth as sensitive as HiRes.

The new study covers HiRes operations during 1997 through 2006, and cosmic rays above the GZK cutoff of 60 billion billion electron volts (6 times 10 to the 19th power). During that period, the observatory detected 13 such cosmic rays, compared with 43 that would be expected without the cutoff. So the detection of only 13 indicates the GZK limit is real, and that most ultrahigh-energy cosmic rays are blocked by cosmic microwave background radiation so that few reach Earth without losing energy.

The discrepancy between HiRes Fly’s Eye and AGASA is thought to stem from their different methods for measuring cosmic rays.

HiRes used multifaceted (like a fly’s eye) sets of mirrors and photomultiplier tubes to detect faint ultraviolet fluorescent flashes in the sky generated when incoming cosmic ray particles hit Earth’s atmosphere. Sokolsky and University of Utah physicist George Cassiday won the prestigious 2008 Panofsky Prize for developing the method.

HiRes measured a cosmic ray’s energy and direction more directly and reliably than AGASA, which used a grid-like array of “scintillation counters” on the ground.

The Search Goes On

University of Tokyo, University of Utah and other scientists now are using the new $17 million Telescope Array cosmic ray observatory west of Delta, Utah, which includes three sets of fluorescence detectors and 512 table-like scintillation detectors spread over 400 square miles – in other words, the two methods that produced conflicting results at HiRes and AGASA. One goal is to figure out why ground detectors gave an inflated count of the number of ultrahigh-energy cosmic rays.

The Telescope Array also will try to explain an apparent shortage in the number of cosmic rays at energies about 10 times lower than the GZK cutoff. This ankle-shaped dip in the cosmic ray spectrum is a deficit of cosmic rays at energies of about 5 billion billion electron volts.

Sokolsky says there is debate over whether the “ankle” represents cosmic rays that run out of “oomph” after being spewed by exploding stars in our galaxy, or the loss of energy predicted to occur when ultrahigh-energy cosmic rays from outside our galaxy collide with the big bang’s afterglow, generating electrons and antimatter positrons.

The Telescope Array and Auger observatories will keep looking for the source of rare ultrahigh-energy cosmic rays that evade the big bang afterglow and reach Earth.

“The most reasonable assumption is they are coming from a class of active galactic nuclei called blazars,” Sokolsky says.

Such a galaxy center is suspected to harbor a supermassive black hole with the mass of a billion or so suns. As matter is sucked into the black hole, nearby matter is spewed outward in the form of a beam-like jet. When such a jet is pointed at Earth, the galaxy is known as a blazar.

“It’s like looking down the barrel of a gun,” Sokolsky says. “Those guys are the most likely candidates for the source of ultrahigh-energy cosmic rays.”

SOURCE:EUREKALERT.ORG
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Bass on 02/04/2008 17:58:53
NASA finds mini-black hole

If you want to know the universe’s ultimate tough guys, look no further than black holes. These strange objects gobble up gas from their surroundings, and sometimes swallow entire stars. But a black hole’s gravity is so powerful that nothing, not even light, can escape its grasp.

But just as Olympic boxing teams have their flyweights, somewhere out there in the depths of space exists the lightest black hole in the universe. It’s still a tough guy, but it’s smaller and lighter than all other members of its kind.

Astronomers may never find the universe’s lightest black hole, but in results announced on March 31, they have come close. Nikolai Shaposhnikov and Lev Titarchuk, who work at NASA’s Goddard Space Flight Center in Greenbelt, Md., have identified the smallest known black hole in the universe. This black hole would weigh the same as 3.8 of our Suns if it could be put on a giant scale.

The Sun is a huge object, and could contain more than a million Earths. So an object weighing the same as 3.8 Suns might sound like a lot. But it’s a pipsqueak when compared to all other known black holes. Previously, the smallest known black hole would weigh about 6.3 Suns, and some black holes tip the scales at millions or even billions of times that of our Sun.

Source: NASA recent news
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 02/04/2008 20:34:51
Awesome Post BASS !!

THANK YOU for your contribution !! !!





10 new planets discovered outside our solar system

UNIVERSITY OF CALIFORNIA-SANTA BARBARA NEWS RELEASE
Posted: April 1, 2008


An international team of astronomers has found 10 new "extra solar" planets, planets that orbit stars other than our sun.

The team used a system of robotic cameras that yield a great deal of information about these other worlds, some of which are quite exotic. The system is expected to revolutionize scientific understanding of how planets form.

Two participating astronomers from the U.S. are Rachel Street and Tim Lister. Street is a postdoctoral fellow at the University of California, Santa Barbara and the Las Cumbres Observatory Global Telescope Network (LCOGTN) located in Santa Barbara. Lister is a project scientist with LCOGTN.

Team leader, Don Pollaco of Queen's University, Belfast, Northern Ireland, will announce the findings in his talk at the Royal Astronomical Society's national astronomy meeting in the U.K. on Wednesday, April 2.

The new international collaboration is called "SuperWASP," for Wide Area Search for Planets.

This technique of locating the planets gives more information about the formation and evolution of the planets than the gravitational technique. Astronomers look for "transits," moments when the planets pass in front of the star, like an eclipse, as viewed from the Earth.

In the last six months the SuperWASP team has used two batteries of cameras, one in Spain's Canary Islands and one in South Africa, to discover the 10 new extra solar planets.

With the gravitational technique, scientists have discovered around 270 extra solar planets since the early 1990s. They measured the gravitational pull on the star that is exerted by the orbiting planet. As the planet moves, it pulls on the star, tugging it back and forth. However, making these discoveries depends on looking at each star over a period of weeks or months, so the pace of discovery is slow.

The SuperWASP technique involves two sets of cameras to watch for events known as transits, where a planet passes directly in front of a star and blocks out some of the star's light. From the Earth the star temporarily appears a little fainter. The

SuperWASP cameras work as robots, surveying a large area of the sky at once. Each night astronomers receive data from millions of stars. They can then check for transits and hence planets. The transit technique also allows scientists to deduce the size and mass of each planet.

A team of collaborators around the world follows up each possible planet found by SuperWASP with more detailed observations to confirm or reject the discovery.

The astronomers working at the Las Cumbres Observatory Global Telescope Network (LCOGTN), affiliated with UC Santa Barbara, use robotically controlled telescopes in Arizona, Hawaii, and Australia. These telescopes provide high quality data used to select the best targets for intense observation. This, together with data from the Nordic Optical Telescope in La Palma, Spain; the Swiss Euler Telescope in Chile; and the Observatoire de Haute Provence in Southern France; provides the final confirmation of the new discoveries.

A total of 46 planets have been found to transit their stars. Since they started operation in 2004, the SuperWASP cameras have found 15 of these. SuperWASP is the most successful transit survey in the world.

The planets discovered by SuperWASP have masses between a middle weight of half the size of Jupiter to more than eight times the size of Jupiter, the largest planet in our solar system.

A number of these new worlds are very exotic. For example, a year, or one orbit, on WASP-12b, is just a bit over one day. This planet is so close to its star that its daytime temperature could reach a searing 2300 degrees Celsius.

Lister and Street from LCOGTN/UCSB are delighted with the results. Street described the discovery as a "very big step forward for the field."

Lister said, "The flood of new discoveries from SuperWASP will revolutionize our understanding of how planets form. LCOGTN's flexible global network of telescopes is an indispensable part of the worldwide effort to learn about the new planets."

Las Cumbres Observatory Global Telescope Network (LCOGTN) is a privately funded, nonprofit organization that is creating a cutting edge science program paired with an innovative education program.


SOURCE:SPACEFLIGHTNOW.ORG
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 01/05/2008 19:45:41
Black hole thrown out of parent galaxy
BY DR EMILY BALDWIN
ASTRONOMY NOW
Posted: April 30, 2008


By an enormous burst of gravitational waves that accompanies the merger of two black holes, a newly formed black hole has been booted out of its parent galaxy at thousands of kilometres per second, confirming theories that extreme ejection events like this can occur and aren’t only plausible in supercomputer simulations.

When two black holes merge, waves of gravitational radiation ripple outward through the galaxy at the speed of light. Because the waves are emitted mainly in one direction, the black hole is forced to recoil in the opposite direction. The result is that the black hole is catapulted out from its normal location in the nucleus of the galaxy, and if the kick velocity is high enough, the black hole can completely escape the gravitational clutches of its parent galaxy. The discovery of a black hole obeying these rules is the first direct observation of its kind, and the astrophysicists working on the project, lead by Stefanie Komossa from the Max Planck Institute for Extraterrestrial Physics (MPE), have confirmed that the several 100 million solar mass black hole was ejected at a speed of 2650 kilometres per second at a distance of 10 billion light years. The black hole’s accretion disc gas is expected to continue to feed the recoiling black hole for millions of years to come.



The new discovery is important as it indirectly proves that black holes do merge, and that these events are sometimes accompanied by large kicks. But another implication is that there must be galaxies without black holes in their nuclei, as well as black holes which float forever in space between the galaxies, which raises a set of new questions: Did galaxies and black holes form and evolve jointly in the early Universe? Or was there a population of galaxies which had been deprived of their central black holes? And if so, how was the evolution of these galaxies different from that of galaxies that retained their black holes?

By consolidating theoretical ideas with direct observations from the ground and from space, the astrophysicists are preparing to answer these questions. But whatever the outcome, this first observation will have far-reaching consequences for our understanding of galaxy formation and evolution in the early Universe.


SOURCE:SPACEFLIGHTNOW.COM

Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 15/05/2008 19:17:37
Iron 'snow' helps maintain Mercury's magnetic field
UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN NEWS RELEASE


CHAMPAIGN, Ill. - New scientific evidence suggests that deep inside the planet Mercury, iron "snow" forms and falls toward the center of the planet, much like snowflakes form in Earth's atmosphere and fall to the ground.

The movement of this iron snow could be responsible for Mercury's mysterious magnetic field, say researchers from the University of Illinois and Case Western Reserve University. In a paper published in the April issue of the journal Geophysical Research Letters, the scientists describe laboratory measurements and models that mimic conditions believed to exist within Mercury's core.

"Mercury's snowing core opens up new scenarios where convection may originate and generate global magnetic fields," said U. of I. geology professor Jie "Jackie" Li. "Our findings have direct implications for understanding the nature and evolution of Mercury's core, and those of other planets and moons."

Mercury is the innermost planet in our solar system and, other than Earth, the only terrestrial planet that possesses a global magnetic field. Discovered in the 1970s by NASA's Mariner 10 spacecraft, Mercury's magnetic field is about 100 times weaker than Earth's. Most models cannot account for such a weak magnetic field.

Made mostly of iron, Mercury's core is also thought to contain sulfur, which lowers the melting point of iron and plays an important role in producing the planet's magnetic field.

"Recent Earth-based radar measurements of Mercury's rotation revealed a slight rocking motion that implied the planet's core is at least partially molten," said Illinois graduate student Bin Chen, the paper's lead author. "But, in the absence of seismological data from the planet, we know very little about its core."

To better understand the physical state of Mercury's core, the researchers used a multi-anvil apparatus to study the melting behavior of an iron-sulfur mixture at high pressures and high temperatures.

In each experiment, an iron-sulfur sample was compressed to a specific pressure and heated to a specific temperature. The sample was then quenched, cut in two, and analyzed with a scanning electron microscope and an electron probe microanalyzer.

"Rapid quenching preserves the sample's texture, which reveals the separation of the solid and liquid phases, and the sulfur content in each phase," Chen said. "Based on our experimental results, we can infer what is going on in Mercury's core."

As the molten, iron-sulfur mixture in the outer core slowly cools, iron atoms condense into cubic "flakes" that fall toward the planet's center, Chen said. As the iron snow sinks and the lighter, sulfur-rich liquid rises, convection currents are created that power the dynamo and produce the planet's weak magnetic field.

Mercury's core is most likely precipitating iron snow in two distinct zones, the researchers report. This double-snow state may be unique among the terrestrial planets and terrestrial-like moons in our solar system.

"Our findings provide a new context into which forthcoming observational data from NASA's MESSENGER spacecraft can be placed," Li said. "We can now connect the physical state of our innermost planet with the formation and evolution of terrestrial planets in general."

With Li and Chen, Case Western Reserve University planetary geodynamics professor Steven A. Hauck II was a co-author of the paper.

The work was funded by the National Science Foundation.
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Lincon on 23/08/2008 09:11:24
I am new to this forum for posting,In another new study reported at the conference, Emmanuel Minot of Stanford University Medical School and his colleagues tested about 2,000 employees of Wisconsin government agencies. Obesity was common in that population, and volunteers who slept either significantly less or more than the overall average tended to be heavier than people getting a moderate amount of sleep, Minot reports. Compared with people who slept 8 hours a night, those who slept 5 hours had 16 percent lower lepton concentrations and 15 percent higher grueling concentrations in their blood.
Ultimately i like to write that Science is the search of truth.

Lincon


mod edit - spammy link removed


Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: SieWhange on 23/08/2008 10:17:09
Hi neilep ...it was a nice method for research of Preserved in crystal.It is very much interesting post.

Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 29/08/2008 21:23:34
Hi neilep ...it was a nice method for research of Preserved in crystal.It is very much interesting post.



Thank You. Glad you enjoyed it.
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 29/08/2008 21:24:50
Mystery star cluster has three different birthdays
SPACE TELESCOPE SCIENCE INSTITUTE NEWS RELEASE
Posted: July 12, 2008

Imagine having three clocks in your house, each chiming at a different time. Astronomers have found the equivalent of three out-of-sync "clocks" in the ancient open star cluster NGC 6791. The dilemma may fundamentally challenge the way astronomers estimate cluster ages, researchers said.

Using NASA's Hubble Space Telescope to study the dimmest stars in the cluster, astronomers uncovered three different age groups. Two of the populations are burned-out stars called white dwarfs. One group of these low-wattage stellar remnants appears to be 6 billion years old, another appears to be 4 billion years old. The ages are out of sync with those of the cluster's normal stars, which are 8 billion years old.

"The age discrepancy is a problem because stars in an open cluster should be the same age. They form at the same time within a large cloud of interstellar dust and gas. So we were really puzzled about what was going on," explained astronomer Luigi Bedin, who works at the Space Telescope Science Institute in Baltimore, Md.

Ivan King of the University of Washington and leader of the Hubble study said: "This finding means that there is something about white dwarf evolution that we don't understand."

After extensive analysis, members of the research team realized how the two groups of white dwarfs can look different and yet have the same age. It is possible that the younger- looking group consists of the same type of stars, but the stars are paired off in binary-star systems, where two stars orbit each other. Because of the cluster's great distance, astronomers see the paired stars as a brighter single star.

"It is their brightness that makes them look younger," said team member Maurizio Salaris of Liverpool John Moores University in the United Kingdom.

Binary systems are also a significant fraction of the normal stellar population in NGC 6791, and are also observed in many other clusters. This would be the first time they have been found in a white-dwarf population.

"Our demonstration that binaries are the cause of the anomaly is an elegant resolution of a seemingly inexplicable enigma," said team member Giampaolo Piotto the University of Padova in Italy.

Bedin and his colleagues are relieved that they now have only two ages to reconcile: an 8-billion-year age of the normal stellar population and a 6-billion-year age for the white dwarfs. All that is needed is a process that slows down white-dwarf evolution, the researchers said.

Hubble's Advanced Camera for Surveys analyzed the cooling rate of the entire population of white dwarfs in NGC 6791, from brightest to dimmest. Most star clusters are too far away and the white dwarfs are too faint to be seen by ground-based telescopes, but Hubble's powerful vision sees many of them.

White dwarfs are the smoldering embers of Sun-like stars that no longer generate nuclear energy and have burned out. Their hot remaining cores radiate heat for billions of years as they slowly fade into darkness. Astronomers have used white dwarfs as a reliable measure of the ages of star clusters, because they are the relics of the first cluster stars that exhausted their nuclear fuel.

White dwarfs have long been considered dependable because they cool down at a predictable rate-the older the dwarf, the cooler it is, making it a seemingly perfect clock that has been ticking for almost as long as the cluster has existed.

NGC 6791 is one of the oldest and largest open clusters known, about 10 times larger than most open clusters and containing roughly 10,000 stars. The cluster is located in the constellation Lyra.

The first results appeared in the May 10 issue of The Astrophysical Journal, and the clarification about binaries was in the May 20 issue of The Astrophysical Journal Letters.

Other members of the research team are Santi Cassisi of the Collurania Astronomical Observatory in Italy, and Jay Anderson, of the Space Telescope Science Institute.




source: Spaceflightnow.org
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 29/08/2008 21:26:30
 
Rare 'star-making machine' found in distant universe
NASA/JPL NEWS RELEASE
Posted: July 11, 2008

Astronomers have uncovered an extreme stellar machine -- a galaxy in the very remote universe pumping out stars at a surprising rate of up to 4,000 per year. In comparison, our own Milky Way galaxy turns out an average of just 10 stars per year.

The discovery, made possible by several telescopes including NASA's Spitzer Space Telescope, goes against the most common theory of galaxy formation. According to the theory, called the Hierarchical Model, galaxies slowly bulk up their stars over time by absorbing tiny pieces of galaxies -- and not in one big burst as observed in the newfound "Baby Boom" galaxy.

"This galaxy is undergoing a major baby boom, producing most of its stars all at once," said Peter Capak of NASA's Spitzer Science Center at the California Institute of Technology, Pasadena. "If our human population was produced in a similar boom, then almost all of the people alive today would be the same age." Capak is lead author of a new report detailing the discovery in the July 10th issue of Astrophysical Journal Letters.

The Baby Boom galaxy, which belongs to a class of galaxies called starbursts, is the new record holder for the brightest starburst galaxy in the very distant universe, with brightness being a measure of its extreme star-formation rate. It was discovered and characterized using a suite of telescopes operating at different wavelengths. NASA's Hubble Space Telescope and Japan's Subaru Telescope, atop Mauna Kea in Hawaii, first spotted the galaxy in visible-light images, where it appeared as an inconspicuous smudge due to is great distance.

It wasn't until Spitzer and the James Clerk Maxwell Telescope, also on Mauna Kea in Hawaii, observed the galaxy at infrared and submillimeter wavelengths, respectively, that the galaxy stood out as the brightest of the bunch. This is because it has a huge number of youthful stars. When stars are born, they shine with a lot of ultraviolet light and produce a lot of dust. The dust absorbs the ultraviolet light but, like a car sitting in the sun, it warms up and re-emits light at infrared and submillimeter wavelengths, making the galaxy unusually bright to Spitzer and the James Clerk Maxwell Telescope.

To learn more about this galaxy's unique youthful glow, Capak and his team followed up with a number of telescopes. They used optical measurements from Keck to determine the exact distance to the galaxy -- a whopping12.3 billion light-years. That's looking back to a time when the universe was 1.3 billion years old (the universe is approximately 13.7 billion years old today).

"If the universe was a human reaching retirement age, it would have been about 6 years old at the time we are seeing this galaxy," said Capak.

The astronomers made measurements at radio wavelengths with the National Science Foundation's Very Large Array in New Mexico. Together with Spitzer and James Clerk Maxwell data, these observations allowed the astronomers to calculate a star-forming rate of about 1,000 to 4,000 stars per year. At that rate, the galaxy needs only 50 million years, not very long on cosmic timescales, to grow into a galaxy equivalent to the most massive ones we see today.

While galaxies in our nearby universe can produce stars at similarly high rates, the farthest one known before now was about 11.7 billion light-years away, or a time when the universe was 1.9 billion years old.

"Before now, we had only seen galaxies form stars like this in the teenaged universe, but this galaxy is forming when the universe was only a child," said Capak. "The question now is whether the majority of the very most massive galaxies form very early in the universe like the Baby Boom galaxy, or whether this is an exceptional case. Answering this question will help us determine to what degree the Hierarchical Model of galaxy formation still holds true."

"The incredible star-formation activity we have observed suggests that we may be witnessing, for the first time, the formation of one of the most massive elliptical galaxies in the universe," said co-author Nick Scoville of Caltech, the principal investigator of the Cosmic Evolution Survey, also known as Cosmos. The Cosmos program is an extensive survey of a large patch of distant galaxies across the full spectrum of light.

"The immediate identification of this galaxy with its extraordinary properties would not have been possible without the full range of observations in this survey," said Scoville.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology, also in Pasadena. Caltech manages JPL for NASA.
 

Source:spaceflightnow.org
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 25/09/2008 01:11:14
Primordial fish had rudimentary fingers

Tetrapods, the first four-legged land animals, are regarded as the first organisms that had fingers and toes. Now researchers at Uppsala University can show that this is wrong. Using medical x-rays, they found rudiments of fingers in the fins in fossil Panderichthys, the “transitional animal,” which indicates that rudimentary fingers developed considerably earlier than was previously thought.

Our fish ancestors evolved into the first four-legged animals, tetrapods, 380 million years ago. They are the forerunners of all birds, mammals, crustaceans, and batrachians. Since limbs and their fingers are so important to evolution, researchers have long wondered whether they appeared for the first time in tetrapods, or whether they had evolved from elements that already existed in their fish ancestors.

When they examined genes that are necessary for the evolution of fins in zebrafish (a ray-finned fish that is a distant relative of coelacanth fishes) and compared them with the gene that regulates the development of limbs in mice, researchers found that zebrafish lacked the genetic mechanisms that are necessary for the development of fingers. It was therefore concluded that fingers appeared for the first time in tetrapods. This reading was supported by the circumstance that the fossil Panderichthys, a “transitional animal” between fish and tetrapod, appeared to lack finger rudiments in their fins.

In the present study, to be published in Nature, medical x-rays (CT scans) were used to reconstruct a three-dimensional image of Panderichthys fins. The results show hitherto undiscovered elements that constitute rudiments of fingers in the fins. Similar rudiments have been demonstrated once in the past, two years ago in Tiktaaliks, which is a more tetrapod-like group. Together with information about fin development in sharks, paddlefish, and Australian lungfish, the scientists can now definitively conclude that fingers were not something new in tetrapods.

“This was the key piece of the puzzle that confirms that rudimentary fingers were already present in ancestors of tetrapods,” says Catherine Boisvert.

Source: Eureka Alert
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Bass on 29/09/2008 20:29:21
Kind of gives those restaurant "fish fingers" a whole new meaning, eh? [;D]
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: ejg1979 on 11/10/2008 20:06:23
Great post on virgin births in sharks this week on the supercollide blog.

http://www.supercollide.com/2008/10/shark-virgin-births-and-anthropology.html

I especially enjoyed the commentary on our own virgin birth stories!
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Pseudogene on 25/10/2008 08:15:39
This appears to be causing quite a stir amongst MS sufferers:
http://www.newscientist.com/article/dn15023-drug-reboots-immune-system-to-reverse-ms.html (http://www.newscientist.com/article/dn15023-drug-reboots-immune-system-to-reverse-ms.html)
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: graham58 on 03/01/2009 12:11:08
Hello, I apologise in advance if this post is in the wrong forum but a while ago there was a competition where the winner received a book on the periodic table that was done in a humourous fashion. I just wondered what the title of this book was and if anyonne knew where it was available?
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: jackflaon on 31/01/2009 09:43:36
Amber reveals ecology of 30 million year old spiders

Scientists at The University of Manchester and the Manchester Metropolitan University have carried out the first comparative scientific study of ancient spiders trapped in amber more than 30 millions years ago.

The study of fossilised spiders from the Baltic (Poland) and the Dominican (Caribbean) regions has revealed new insights into the ecologies of spiders dating back to the Cenozoic period.

It is the first time ancient spiders from different parts of the world have been compared on such a large scale. 671 species of spiders were compared in the study which is published in the March issue of the Royal Society's Journal Biology Letters.

Palaeoarachnologist Dr David Penney, of The University of Manchester's School of Earth, Atmospheric and Environmental Sciences who led the research, said: "Amber provides a unique window into past forest ecosystems. It retains an incredible amount of information, not just about the spiders themselves, but also about the environment in which they lived.

"We have not only been able to compare the size distributions of over 600 spiders but we have also been able to gain unique insights into the forest in which they lived."

By analysing the size distributions of the spiders and comparing the distinct hunting traits of each species, Dr Penney found that web-spinning spiders were bigger in Baltic amber than in Dominican amber, but that there was no difference between hunting spiders in either region. It was also found the fauna of the amber producing trees in each region accounted for this difference in size.

"Several lines of evidence show that greater structural complexity of Baltic compared to Dominican amber trees explains the presence of larger web-spinners. The Dominican trees are long, thin and smooth whereas the Baltic trees are wide and bushy, providing a much better environment for web-spinners to prosper," says Dr Penney.

The study demonstrates for the first time that spiders trapped in amber can be scientifically compared across deep time (30 million years). This is due to the fact that until now it was unknown whether the amber resins were trapping organisms uniformly. This study proves they were.

Mod edit - spammy link removed and blacklisted
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: paul.fr on 17/03/2009 17:09:18
Scientists find new bacteria species

From Harmeet Shah Singh
CNN
Decrease font Decrease font
Enlarge font Enlarge font

NEW DELHI, India (CNN) -- Indian scientists have discovered three new species of bacteria in Earth's upper stratosphere that are resistant to ultraviolet radiation, researchers said.

The bacteria do not match any species found on Earth. They were found in samples that scientists collected when they sent a balloon into the stratosphere, the Indian Space Research Organization (ISRO) said in a statement Monday.

That layer of the Earth receives heavy doses of ultraviolet radiation, enough to kill most organisms.

In their analyses of the retrieved samples, microbiologists detected 12 bacterial and six fungal colonies.

Of them, three bacterial colonies were new species, the ISRO said.

Indian scientists named one of them Janibacter hoylei, after astrophysicist Fred Hoyle.

"While the present study does not conclusively establish the extraterrestrial origin of microorganisms, it does provide positive encouragement to continue the work in our quest to explore the origin of life," the ISRO said

http://edition.cnn.com/2009/TECH/science/03/17/india.bacteria/index.html?eref=ib_topstories
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: 112inky on 25/03/2009 04:59:56
going through these pages im constantly reminded of just how small and insignificant we really are,like a speck of dust in the vastness of space.

that's true friend... when i visited the great Himalayas... i was dumbstruck by its majestic and had the same feeeling....we are truly a speck of dust in this universe....
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: 112inky on 28/03/2009 12:45:53
The recent warming trend in the Atlantic Ocean is largely due to reductions in airborne dust and volcanic emissions during the past 30 years, according to a new study...
Since 1980, the tropical North Atlantic has been warming by an average of a quarter-degree Celsius (a half-degree Fahrenheit) per decade. Though this number sounds small, it can translate to big impacts on hurricanes, which thrive on warmer water, says Amato Evan, a researcher with the University of Wisconsin-Madison's Cooperative Institute for Meteorological Satellite Studies and lead author of the new study. For example, the ocean temperature difference between 1994, a quiet hurricane year, and 2005's record-breaking year of storms, was just one degree Fahrenheit...... [:(]
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Chemistry4me on 29/05/2009 06:02:49
A good egg

27 May 2009


UK and Dutch scientists have mimicked an ancient Chinese culinary technique of preserving eggs to study how proteins cause disease.
 
Erika Eiser from the University of Cambridge and colleagues looked at how proteins in egg whites altered during this preservation process. The Chinese method involves wrapping raw eggs in an alkaline paste of lime, clay, salt, ash and tea and storing these so-called century eggs for several months. Eiser modified the method by incubating a boiled egg in a strong alkaline sodium hydroxide-salt solution for up to 26 days.

After peeling back the shell, Eiser found that the egg white had transformed into a gel. This transformation is caused by changes in the way protein strands, called ovalbumin, in the white are held together. Boiling an egg causes bonds between the protein strands to break and the proteins to partially unfold. The proteins then come together, or aggregate, in a different way to form the opaque and brittle white. The transformation was thought to be irreversible, but the alkali causes the proteins in the white to aggregate into fine strands to form a transparent and elastic gel. Eiser found that the gel was more stable than the white, and could be heated without changing its structure.

Paul Bartlett, an expert in colloids and protein aggregation at the University of Bristol, UK, comments that Eiser's findings 'will be important for understanding protein gels and will inspire more work in colloidal materials.'

'Similar chemical transformations could be used to change the properties of protein aggregates not only in food but also in other biomaterials,' says Eiser, who plans to test the method on different proteins. 'If we understand the mechanism that drives aggregation then we could slow it down or reverse the aggregation into something else.' This could be important in preventing diseases caused by unnatural protein aggregation such as Alzheimer's.

Anna Roffey

http://www.rsc.org/Publishing/ChemScience/Volume/2009/07/good_egg.asp
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: SherlockScience on 28/08/2009 11:12:46
There will soon be a orchestra which consists of dead musical instruments (like the "epigonion" and the "salpinx") which have been recreated using computer modeling, called the "Lost Sounds Orchestra":

http://www.isgtw.org/?pid=1001954

I wonder what it will sound like!
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 28/08/2009 21:23:22
The "Great Wall" Of Space: Galactic Superclusters a Billion Light Years Away Extend for 5% of Observable Universe

 [ Invalid Attachment ]

GreatWall: The vastest structure ever is a collection of superclusters a billion light years away extending for 5% the length of the entire observable universe.  Insert "yo mamma" joke here.  If it took a God one week to make the Earth, going by mass it would take him two quintillion years to build this thing - far longer than science says the universe has existed for, and it's kind of fun to have those two the other way round for a change.  Though He could always omnipotently cheat and say "Let there be a Sloan Great Wall."


The great wall is a massive array of astronomical objects named after the observations which revealed them, the Sloan Digital Sky Survey.  An eight year project scanned over a quarter of the sky to generate full 3-D maps of almost a million galaxies.  Analysis of these images revealed a huge panel of galaxies 1.37 billion light years long, and even the pedantic-sounding .07 there is six hundred and sixty billion trillion kilometers.  This is science precisely measuring made-up sounding numbers.

This isn't the only wall out there - others exist, all with far greater lengths than width or depth, actual sheets of galaxies forming some of the most impressive anythings there are.  And these walls are only a special class of galactic filaments, long strings of matter stretched between mind-breaking expanses of emptiness.

The immensity of existence truly defies human understanding - which makes it very humanly awesome of us to try anyway.  If people could understand for a single second the true scale of everything out there, all our idiotic problems would evaporate instantly.  (Either because we got our acts together or our heads popped, no bets on which.)

Luke McKinney
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: spiderhex on 21/09/2009 12:51:28
just a quick reply to the article on conkers v. spiders.....it really does work...in my place it does, have also collected some more conkers to give to my neighbour.
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 07/10/2009 13:17:32
WOO !!

http://www.thenakedscientists.com/forum/index.php?topic=957.msg278624#msg278624
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: jameswilliam on 08/10/2009 11:58:54
welcome to my website.........


click here (http://"www.google.com")
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: BenV on 08/10/2009 12:27:43
Really James?  Google.com is your website?
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 08/10/2009 13:05:19
cool site James  ..I hope it catches on ! [::)]
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: tiptop on 18/10/2009 22:11:52
Hi all this is very much informative, I enjoy your posts.
I have a question

Could the colour vision come before the blush? otherwise what use would the blush be.
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: BenV on 18/10/2009 23:17:49
Hi all this is very much informative, I enjoy your posts.
I have a question

Could the colour vision come before the blush? otherwise what use would the blush be.

Hi Tiptop,

Not many people will see your question in this thread, might I recommend starting a new thread (perhaps in the "Plant sciences zoology & evolution board?) with your question as the subject? 

That should get more attention and the discussion it deserves.
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Geezer on 19/10/2009 00:01:57
DIY Black Hole info from the Disco (Discovery) Channel

http://blogs.discovery.com/space_disco/2009/10/first-ever-black-hole-created-on-earth.html
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Kerry on 11/11/2009 09:33:33
Lab News just ran a few stories on the possible causes of the mass extinction of the dinosaurs:

http://www.labnews.co.uk/laboratory_article.php/4968/2/2/did-this-kill-off-the-dinosaurs?

http://www.labnews.co.uk/laboratory_article.php/4970/2/2/mass-extinction-%E2%80%93-could-it-be-due-to-algae?-

Can't decide which one is more plausible...
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: steammafe on 16/11/2009 23:40:43
Here we go again. Unless there is nuclear fussion involved its not very likely any science is involved, but there is always someone wanting to make money.
 
What is so hard to understand that water is the ash of burning hydrogen? You dont get energy from ash.
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Ron Hughes on 01/02/2010 20:29:33
Both
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 30/09/2011 17:18:53
Vast Cosmic Filament Discovered Connecting Milky Way to the Universe




 [ Invalid Attachment ]

Astronomers at The Australian National University have discovered proof of a vast filament of material that connects our Milky Way galaxy to nearby clusters of galaxies, which are similarly interconnected to the rest of the Universe.

“By examining the positions of ancient groupings of stars, called globular clusters, we found that the clusters form a narrow plane around the Milky Way rather than being scattered across the sky,” said Dr. Stephan Keller of the Research School of Astronomy and Astrophysics at ANU.


“Furthermore, the Milky Way’s entourage of small satellites are seen to inhabit the same plane. What we have discovered is evidence for the cosmic thread that connects us to the vast expanse of the Universe. The filament of star clusters and small galaxies around the Milky Way is like the umbilical cord that fed our Galaxy during its youth,” Keller observed.

There are two types of matter that made up the Universe – the dominant, enigmatic dark matter and ordinary matter in the form of galaxies, stars and planets. “A consequence of the Big Bang and the dominance of dark matter is that ordinary matter is driven, like foam on the crest of a wave, into vast interconnected sheets and filaments stretched over enormous cosmic voids – much like the structure of a kitchen sponge."

“Unlike a sponge, however," Keller added, "gravity draws the material over these interconnecting filaments towards the largest lumps of matter, and our findings show that the globular clusters and satellite galaxies of the Milky Way trace this cosmic filament. Globular clusters are systems of hundreds of thousands of ancient stars tightly packed in a ball. In our picture, most of these star clusters are the central cores of small galaxies that have been drawn along the filament by gravity.
“Once these small galaxies got too close the Milky Way the majority of stars were stripped away and added to our galaxy, leaving only their cores.

“It is thought that the Milky Way has grown to its current size by the consumption of hundreds of such smaller galaxies over cosmic time,” he concluded.

The Daily Galaxy via Australian National University


Image credit: IAC
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Apple on 04/10/2011 00:35:54
Chance we broke the speed of light

http://www.universetoday.com/89135/breaking-the-speed-of-light/

still not proven but a chance
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: awais_x on 09/10/2011 21:07:23
Hi !!!!
I am very happy to see this site by increase my general knowledge please share more information about the science ....

WOOPS! I SEEM TO HAVE DROPPED SOME SPAM HERE.
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 14/10/2011 19:51:47
Mystery allergy causes woman to age decades


 [ Invalid Attachment ]



Left: Nguyen Thi Phuong aged 21. Right: Now aged 26. Photo: Hotspot Media.





A 26-year-old Vietnamese woman has left doctors baffled as she lost her once youthful appearance.

Nguyen Thi Phuong believes that an allergic reaction to seafood she ate in 2008, caused the skin over her face and body to sag and wrinkle. It has come to light now, as she has shown her face in public for the first time since it happened.

Her story has led health experts to question what could have triggered her rapid aging as pictures show Phuong looking like two different people.





Mrs Nguyen had been treating herself with various types of medication, from a local pharmacy as she and her husband could not afford to have her examined at a hospital.

She said: “I was really itchy all over my body. I had to scratch even while sleeping. After one month of taking the drugs, I became less itchy but hives remained on my skin.

[See also: Woman is so bloated after eating people think she is pregnant]

“Then I switched to traditional medicine and all the hives disappeared, together with my itching. However, my skin began to sag and fold.”

The couple does not remember what the traditional medication was called, or which pharmacy they had bought it from.

In 2009 they decided to stop using the remedy; from then on Phuong wore a face mask whenever she was in public.

She said: “The skin on my face, chest and belly has folds like an old woman who has given birth several times although I have never had a child.

“But the rapid-aging syndrome hasn't affected my menstrual cycle, hair, teeth, eyes and mind.”

Phuong’s husband, Thanh Tuyen, insists her story is true and continues to stand by his wife despite the loss of her youthful appearance.

Tuyen said: “I married Phuong when she was a beautiful woman. I have followed her through her disease and have never been shocked at all.

“It's not easy to talk about one's own marital affairs. Just simply understand that I still love her very much.”

Mrs Nguyen has not had much luck treating her condition but there still may be a happy ending.

Phuong was able to have a free consultation at the Ho Chi Minh City Medicine and Pharmacy University Hospital, in Vietnam, with doctors who believed she may have been badly affected with the skin disease, mastocytosis.

From this diagnosis, doctors hope that with medical treatment they will be able to restore between 50 and 70% of her skin.




http://uk.lifestyle.yahoo.com/mystery-allergy-causes-woman-to-age-decades-in-just-a-few-days.html
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Geezer on 14/10/2011 20:48:25
Mystery allergy causes woman to age decades


A 26-year-old Vietnamese woman has left doctors baffled as she


Are ewe sure somebody is not blowing smoke up your kilt?
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 15/10/2011 01:47:09
Mystery allergy causes woman to age decades


A 26-year-old Vietnamese woman has left doctors baffled as she


Are ewe sure somebody is not blowing smoke up your kilt?

I did wonder if it was fake before posting. I even checked todays date to see if it was April 1st...but..it seems to be legitimately reported !....Would be good to get bona-fide verification though one way or another.

I only wear my kilt at Hogmanay !
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: RD on 15/10/2011 03:36:24
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fimage.thenakedscientists.com%2Fforum%2Findex.php%3Faction%3Ddlattach%3Btopic%3D3633.0%3Battach%3D15409%3Bimage&hash=9991765a0e33041ff38b4ed106daf478)

The premature aging is due to the stress from watching Chelsea play [:)] (see bottom right corner)

The story looks bogus to me, but there are astronomically rare syndromes which cause people to age rapidly ...
http://biologylastscience.blogspot.com/2011/03/werner-syndrome.html
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Geezer on 15/10/2011 07:25:11
It's probably the same person, with a fifty year gap between the photographs. If so, the one on the left was not taken with a digital camera.

The other intersting thing is the stretching of the earlobes. I'd be very surprised if that was caused by anything other than earrings, and a lot of time.
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: RD on 15/10/2011 07:32:09
It's probably the same person, with a fifty year gap between the photographs

More like mother and daughter: different shnozes : ma's nostrils are visible, daughter's ain't.
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Geezer on 15/10/2011 07:39:04
It's probably the same person, with a fifty year gap between the photographs

More like mother and daughter: different shnozes : ma's nostrils are visible, daughter's ain't.

Could be, but the one on the left has a very low res. photographic emulsion look about it.
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: damocles on 15/10/2011 09:07:44
Item hit the news here, together with an interview with a dermatologist who had actually examined the woman. His story was that it was a rare form of dermatitis, and arose because the woman had not sought help quickly for a skin infection, but allowed a month to pass using only traditional Chinese type folk remedies. When she eventually sought hospital help it was too late for her skin -- then covered in lesions -- to recover properly. He maintained that her internal organs were all in good condition, and were those of a 26-year -old.
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 15/10/2011 14:57:14
It's probably the same person, with a fifty year gap between the photographs

More like mother and daughter: different shnozes : ma's nostrils are visible, daughter's ain't.

Could be, but the one on the left has a very low res. photographic emulsion look about it.

Actually, the picture on the left looks like a photo of a photo !
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: neilep on 15/10/2011 14:57:56
Item hit the news here, together with an interview with a dermatologist who had actually examined the woman. His story was that it was a rare form of dermatitis, and arose because the woman had not sought help quickly for a skin infection, but allowed a month to pass using only traditional Chinese type folk remedies. When she eventually sought hospital help it was too late for her skin -- then covered in lesions -- to recover properly. He maintained that her internal organs were all in good condition, and were those of a 26-year -old.

Thanks for this...further corroborative info !
Title: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Geezer on 15/10/2011 16:49:25
Item hit the news here, together with an interview with a dermatologist who had actually examined the woman. His story was that it was a rare form of dermatitis, and arose because the woman had not sought help quickly for a skin infection, but allowed a month to pass using only traditional Chinese type folk remedies. When she eventually sought hospital help it was too late for her skin -- then covered in lesions -- to recover properly. He maintained that her internal organs were all in good condition, and were those of a 26-year -old.

Lesions my ass - ouch! Methinks somebody is pulling off a big hoax. (Journalists believe gullible isn't in the dictionary.)

I wonder if Chris is buying any of this.
Title: Re: Recent Science News Stories and Science Articles
Post by: neilep on 28/09/2012 22:53:22
New Comet Discovered—May Become "One of Brightest in History"

Astronomers have discovered a new comet which will be visible in late 2013 and is predicted to be brighter than the full moon.
If predictions are correct, C/2012 S1 will be one of the greatest comets in human history, far outshining both the the memorable Comet Hale-Bopp of 1997 (pictured) and very likely to outdo the long-awaited Comet Pan-STARRS (C/2011 L4) which is set to pass us by March 2013.
It's thought that this is the first time this particular comet has ever passed through the inner solar system - meaning it's never been blasted by the sun before.
Its brightness magnitude is expected to be -16. In comparison, the sun has a magnitude of -26, and Comet Hale-Bopp was magnitude -1



* 44227_478990935455256_364619550_n.jpg (62.24 kB . 630x328 - viewed 9515 times)

I Can't Wait To See That !


Title: Re: Recent Science News Stories and Science Articles
Post by: Karen W. on 29/09/2012 05:57:22
HOW EXCITING...I CAN'T WAIT FOR YOU TO SEE IT ALSO.. I WOULD LIKE TO TAKE A GOOD LONG GANDER MYSELF! WILL YOUR SCOPE BE ABLE TO GET THE JOB DONE?
Title: Re: Recent Science News Stories and Science Articles
Post by: neilep on 29/09/2012 23:20:26
HOW EXCITING...I CAN'T WAIT FOR YOU TO SEE IT ALSO.. I WOULD LIKE TO TAKE A GOOD LONG GANDER MYSELF! WILL YOUR SCOPE BE ABLE TO GET THE JOB DONE?

It'll be visible to the naked eye..I remember the Hale Bop  (http://en.wikipedia.org/wiki/Hale_bop)was easily observed (I saw it) with the naked eye and this one is going to be a lot lot brighter !
Title: Re: Recent Science News Stories and Science Articles
Post by: Karen W. on 30/09/2012 01:45:50
THATS REALLY COOL...MARCH 2013, THEN AGAIN IN LATE 2013....THERE WILL LIKELY BE FURTHER ANNOUNCEMENTS AS IT DRAWS NEAR... I HAVE TO ADD IT INTO MY CALANDER ACTIVITIES..... THANKS. FOR TELLING ME THAT.. I WILL LOOK FORWARD TO SEEING IT...
Title: Re: Recent Science News Stories and Science Articles
Post by: CliffordK on 30/09/2012 07:22:00
New Comet Discovered—May Become "One of Brightest in History"
Oh...
It isn't smacking into the Earth, is it?
The "Mayan Prediction?"

Early Spring isn't always the best time for visualizing stuff in the sky around here.  Hopefully there will be a few clear nights.  Perhaps I'll have to find a secluded area to stare at the stars.
Title: Re: Recent Science News Stories and Science Articles
Post by: Karen W. on 30/09/2012 22:53:54
That sounds like a really nice idea Clifford and romantic as well! It would be a really nice date night, you better take YOUR someone special!
Title: Re: Recent Science News Stories and Science Articles - Deleted by Geezer at 2011-11-25 01:12:05
Post by: Danielle-v-wilson on 22/09/2013 21:25:59
Beaver or Otter, It Lived in Dinosaurs' Time

Awesome and exciting new discovery! It would be interesting to discover how closely related this species is to otters, beavers or the platypus.
Title: Re: Recent Science News Stories and Science Articles
Post by: distimpson on 27/10/2013 11:43:08
http://www.bbc.co.uk/podcasts/series/drkarl (http://www.bbc.co.uk/podcasts/series/drkarl)

this may be old news but new to me, just found this link to Dr Karl and the Naked Scientist on BBC radio 5 live.
Title: Re: Recent Science News Stories and Science Articles
Post by: JoeBrown on 11/12/2016 16:43:02
This seems like news to me.  Its not graced the mass media waves much tho.

http://nsidc.org/arcticseaicenews/

The Arctic is unseasonably warm.  80˚ North has been in polar night over a month and a half.  Nearly a month ago, it it 36F (20C) degrees above normal, which did grace some headlines.  Since then, not much in the way of news.

https://14adebb0-a-62cb3a1a-s-sites.googlegroups.com/site/arctischepinguin/home/sea-ice-extent-area/grf/nsidc_global_area_byyear_b.png

The attached chart is one I composed from from http://ocean.dmi.dk/arctic/meant80n.uk.php

It's based on the most recent 2016 and has 2011-2015 plot history superimposed in cyan.

Top that off with unusual early/excessive melting of Antarctica, I find it all highly disturbing that it's not in the "news."  Does it explain Trump being president - elect??? No, but its freakishly coincidental.


* NorthPoleNovember2016.png (17.1 kB . 600x400 - viewed 6689 times)
Title: Re: Recent Science News Stories and Science Articles
Post by: Jajdj on 20/11/2017 17:14:58
Finally I found this Here Thanks Keep Posting.!
Title: Re: Recent Science News Stories and Science Articles
Post by: RidaChat on 12/07/2019 03:10:00
Hayabusa2 may have just snagged bits of asteroid Ryugu’s insides
The Japanese spacecraft returns to Earth in 2020 with the first subsurface space rock sample
BY LISA GROSSMAN 10:38AM, JULY 11, 2019


The Hayabusa2 spacecraft has made its second and final attempt to grab a pinch of dust from asteroid Ryugu. At about 9:06 p.m. EDT on July 10, the Japanese spacecraft briefly touched down near an artificial crater it had previously blasted into the 4.5-billion-year-old asteroid’s surface. If the dust grab went well, it’s the first spacecraft to ever collect a sample from an asteroid’s insides.

"We've collected a part of the solar system's history," said project manager Yuichi Tsuda, of the Japanese Aerospace Exploration Agency, at a July 11 press conference.

Hayabusa2 first successfully touched down on Ryugu’s surface on February 22, after months of experiments on Earth to make sure the spacecraft’s sample collection technique would work on the asteroid’s surprisingly rocky surface (SN Online: 2/22/19). The strategy involves firing a tantalum bullet at close range into the surface to kick up surface dust and then catching some of that dust in a long, flared horn (SN: 1/19/19, p. 20).

In April, the spacecraft dropped a two-kilogram copper cylinder from about 500 meters above the asteroid to blast an artificial crater about 10 meters wide and 2 meters deep into its surface (SN Online: 4/26/19), in preparation for the second sample retrieval. Its goal: To stir up buried material that hasn’t seen sunlight for up to billions of years.

“Touchdown is a high risk operation,” the team wrote on its website July 8 in preparation for the second sample retrieval. “Just because we have succeeded in the past does not mean we can easily do so again.”

The Japanese space agency decided to aim Hayabusa2 at an area about 20 meters north of the crater’s center, where it looks like dark material from inside the crater landed. After hours of descending toward the asteroid’s surface, Hayabusa2 briefly tapped the targeted spot and fired the bullet, creating a spray of pebbles. The spacecraft immediately started to rise again. At 9:51 p.m. EDT, mission control received word that the spacecraft was safe.

Marks the spot
Hayabusa2 touched down inside the circle marked on this terrain map of asteroid Ryugu. Scientists think dirt excavated from a nearby artificial crater (dotted line) landed there, allowing Hayabusa2 to take a sample of subsurface material. The white dot (arrow) indicates a target marker that Hayabusa2 dropped before the touchdown to help it navigate to the touchdown area.


JAXA
“The state of the spacecraft is normal and the touchdown sequence was performed as scheduled,” the team tweeted. “Project Manager Tsuda has declared that the 2nd touchdown was a success!”

Hayabusa2 will leave Ryugu in November or December, and is expected to arrive back at Earth in 2020. That’s when the team will confirm that the spacecraft successfully collected the dust. Studying material from the asteroid’s surface and subsurface will let scientists tease out details of the asteroid’s history and the early history of the solar system (SN: 4/13/19, p. 11).
Title: Re: Recent Science News Stories and Science Articles
Post by: James Farr on 24/07/2019 15:20:47
Parallel evolution has recently become intriguing to many geneticists. Many examples of genes transferred from unrelated species can occur in plants, and now mammals. Findings are found in molecular taxonomic studies in wildflowers and mammals.the use of biogenomics in taxonomy has opened doors to the study of evolution.The discoveries have been compared to the finding of jumping genes in the late1970's.Research is occurring with crop species finding more heat resistant strains through interbreeding rather than bioengineering.