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ROBERT

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" 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
« Last Edit: 23/08/2006 15:55:13 by ROBERT »
 

Offline neilep

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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 !
 

Offline ariel

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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.


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

ariel
« Last Edit: 24/08/2006 00:15:21 by ariel »
 

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who responsible for going to wide and taking this page over the edge.

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« Last Edit: 24/08/2006 03:22:52 by ukmicky »
 

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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.
 

ROBERT

  • Guest
" 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
« Last Edit: 23/08/2006 15:55:13 by ROBERT »
 

Offline neilep

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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 !
 

ROBERT

  • Guest
" 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
« Last Edit: 23/08/2006 15:55:13 by ROBERT »
 

Offline neilep

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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 !
 

Offline ariel

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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.


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

ariel
« Last Edit: 24/08/2006 00:15:21 by ariel »
 

Offline ukmicky

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who responsible for going to wide and taking this page over the edge.

Michael
« Last Edit: 24/08/2006 03:22:52 by ukmicky »
 

Offline Mjhavok

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    • http://cantmakeadifference.blogspot.com
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.
 

ROBERT

  • Guest
" 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
« Last Edit: 23/08/2006 15:55:13 by ROBERT »
 

Offline neilep

  • Withdrawnmist
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    • View Profile
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 !
 

Offline ariel

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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.


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

ariel
« Last Edit: 24/08/2006 00:15:21 by ariel »
 

Offline ukmicky

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who responsible for going to wide and taking this page over the edge.

Michael
« Last Edit: 24/08/2006 03:22:52 by ukmicky »
 

Offline Mjhavok

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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)

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" 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 Š 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

 

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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

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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  

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

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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
 

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" 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
« Last Edit: 31/08/2006 16:25:02 by ROBERT »
 

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" 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
« Last Edit: 31/08/2006 16:25:02 by ROBERT »
 

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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

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" 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" :)
« Last Edit: 13/09/2006 15:57:27 by ROBERT »
 

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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.

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