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Author Topic: A-Z Of Anything Or Anyone Associated With SCIENCE !!  (Read 346296 times)

Offline Karen W.

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LOL.. Me neither! Hee hee!

Lithium
From Wikipedia

Lithium (pronounced /ˈlɪθiəm/) is a chemical element with the symbol Li and atomic number 3. It is a soft alkali metal with a silver-white color. Under standard conditions, it is the lightest metal and the least dense solid element. Like all alkali metals, lithium is highly reactive, corroding quickly in moist air to form a black tarnish. For this reason, lithium metal is typically stored under the cover of oil.

According to theory, lithium (mostly 7Li) was one of the few elements synthesized in the Big Bang, although its quantity has vastly decreased. The reasons for its disappearance and the processes by which new lithium is created continue to be important matters of study in astronomy. Lithium is the 33rd most abundant element on Earth, [1] but due to its high reactivity only appears naturally in the form of compounds. Lithium occurs in a number of pegmatitic minerals, but is also commonly obtained from brines and clays; on a commercial scale, lithium metal is isolated electrolytically from a mixture of lithium chloride and potassium chloride.

Trace amounts of lithium are present in the oceans and in some organisms, though the element serves no apparent biological function in humans. Nevertheless, the neurological effect of the lithium ion Li+ makes some lithium salts useful as a class of mood stabilizing drugs. Lithium and its compounds have several other commercial applications, including heat-resistant glass and ceramics, high strength-to-weight alloys used in aircraft, and lithium batteries. Lithium also has important links to nuclear physics: the splitting of lithium atoms was the first man-made form of a nuclear reaction, and lithium deuteride serves as the fusion fuel in staged thermonuclear weapons.
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Maxwell, James Clerk
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James Clerk Maxwell (13 June 1831 – 5 November 1879) was a Scottish mathematician and theoretical physicist. His most significant achievement was the development of the classical electromagnetic theory, synthesizing all previous unrelated observations, experiments and equations of electricity, magnetism and even optics into a consistent theory.[1] His set of equations—Maxwell's equations—demonstrated that electricity, magnetism and even light are all manifestations of the same phenomenon: the electromagnetic field. From that moment on, all other classical laws or equations of these disciplines became simplified cases of Maxwell's equations. Maxwell's work in electromagnetism has been called the "second great unification in physics", after the first one carried out by Newton.

Maxwell demonstrated that electric and magnetic fields travel through space in the form of waves, and at the constant speed of light. Finally, in 1864 Maxwell wrote A Dynamical Theory of the Electromagnetic Field where he first proposed that light was in fact undulations in the same medium that is the cause of electric and magnetic phenomena. His work in producing a unified model of electromagnetism is considered to be one of the greatest advances in physics.

Maxwell also developed the Maxwell distribution, a statistical means to describe aspects of the kinetic theory of gases. These two discoveries helped usher in the era of modern physics, laying the foundation for future work in such fields as special relativity and quantum mechanics. He is also known for creating the first true colour photograph in 1861.

Maxwell is considered by many physicists to be the most influential nineteenth century scientist on twentieth century physics. His contributions to the science are considered by many to be of the same magnitude as those of Isaac Newton and Albert Einstein. In 1931, on the centennial of Maxwell's birthday, Einstein himself described Maxwell's work as the "most profound and the most fruitful that physics has experienced since the time of Newton.





 

Offline rosalind dna

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NADIR

From Wiki



Diagram showing the relationship between the Zenith, the Nadir, and different types of Horizon. Note how the Nadir is opposite the Zenith.The nadir (from Arabic ندير nadeer نظير nathir, "opposite") is the astronomical term for the point directly below the observer, or more precisely, the point with an inclination of −90°. In simple terms, if you are standing on the Earth, it is the direction "down" toward your feet.




Geometrically, it is the point on the celestial sphere intersected by a line drawn from the observer's location on the Earth's surface through the center of the Earth. The point opposite the nadir is the zenith. Nadir also refers to a downward-facing viewing angle of an orbiting satellite[2], such as is employed during remote sensing of the atmosphere, as well as when an astronaut faces the Earth while performing an EVA.

The word is also used figuratively to mean the lowest point of a person's spirits. [

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Ostrom, John
From Wikipedia, the free encyclopedia






John H. Ostrom (February 18, 1928 – July 16, 2005) was an American paleontologist who revolutionized modern understanding of dinosaurs in the 1960s, when he demonstrated that dinosaurs are more like big non-flying birds than they are like lizards (or "saurians"), an idea first proposed by Thomas Henry Huxley in the 1860s, but which had garnered few supporters. The first of Ostrom's broad-based reviews of the osteology and phylogeny of the primitive bird Archaeopteryx appeared in 1976. His reaction to the eventual discovery of feathered dinosaurs in China, after years of acrimonious debate, was bittersweet (Gentile, 2000).
 

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 Palmieri , Luigi
From Wikipedia, the free encyclopedia

Luigi Palmieri (April 22, 1807 - September 9, 1896) was an Italian physicist and meteorologist.


He was born at Faicchio, Benevento, Italy. He died at Naples, Italy. Palmieri made observation of the eruptions on Mount Vesuvius. He also researched earthquakes and meteorological phenomena.

Palmieri received a degree in architecture from the University of Naples. In 1845, Palmieri was the professor of physics at the Royal Naval School at Naples. In 1847, Palmieri was the chair of physics at the university. In 1848, he began working at the Vesuvius Observatory. By 1854, Palmieri was the observatory director. Using a seismometer for the detection and measurement of ground tremors, Palmieri was able to detect very slight movements and to predict the eruption of volcanos.

Using a modified Peltier electrometer, he researched atmospheric electricity. He developed a modified Morse telegraph. He improved the anemomete and pluviometer.
 

Offline rosalind dna

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Quinine



Quinine (IPA: /ˈkwaɪnaɪn, kwɪˈniːn, ˈkwiːniːn/) is a natural white crystalline alkaloid having antipyretic (fever-reducing), antimalarial, analgesic (painkilling), and anti-inflammatory properties and a bitter taste. It is a stereoisomer of quinidine.

Quinine was the first effective treatment for malaria caused by Plasmodium falciparum, appearing in therapeutics in the 17th century. It remained the antimalarial drug of choice until the 1940s, when other drugs took over. Since then, many effective antimalarials have been introduced, although quinine is still used to treat the disease in certain critical situations. Quinine is available with a prescription in the United States. Quinine is also used to treat nocturnal leg cramps and arthritis, and there have been attempts (with limited success) to treat prion diseases. It was once a popular heroin adulterant.


It was first brought to Europe by Jesuits and it was also used to cure King Louis XIV.
Chemical structure
Quinine contains two major fused-ring systems: The aromatic quinoline and the bicyclic quinuclidine.

Mechanism of action against P. falciparum
The drug acts by inhibiting the hemozoin biocrystallization, thus facilitating an aggregation of cytotoxic heme. Toxic free heme accumulates in the parasites, leading to their death.

History
Quinine was extracted from the bark of the South American cinchona tree and was isolated and named in 1817 by French researchers Pierre Joseph Pelletier and Joseph Bienaimé Caventou. The name was derived from the original Quechua (Inca) word for the cinchona tree bark, "Quina" or "Quina-Quina", which roughly means "bark of bark" or "holy bark". Prior to 1820, the bark was first dried, ground to a fine powder and then mixed into a liquid (commonly wine) which was then drunk.

Large scale use of quinine as a prophylaxis started around 1850, although it had been used in un-extracted form by Europeans since at least the early 1600s. Quinine was first used to treat malaria in Rome in 1631. During the 1600s, malaria was endemic to the swamps and marshes surrounding the city of Rome. Over time, malaria was responsible for the death of several Popes, many Cardinals and countless common citizens of Rome. Most of the priests trained in Rome had seen malaria victims and were familiar with the shivering brought on by the cold phase of the disease. In addition to its anti-malarial properties, quinine is an effective muscle relaxant, long used by the Quechua Indians of Peru to halt shivering brought on by cold temperatures. The Jesuit Brother Agostino Salumbrino (1561-1642), an apothecary by training and who lived in Lima, observed the Quechua using the quinine-containing bark of the cinchona tree for that purpose. While its effect in treating malaria (and hence malaria-induced shivering) was entirely unrelated to its effect in controlling shivering from cold, it was still the correct medicine for malaria. At the first opportunity, he sent a small quantity to Rome to test in treating malaria. In the years that followed, cinchona bark became one of the most valuable commodities shipped from Peru to Europe.

Quinine also played a significant role in the colonization of Africa by Europeans. As the harbinger of modern pharmacology, Quinine was the prime reason why Africa ceased to be known as the white man's grave. According to socialist historian Clifford Conner in "A People's History of Science", "It was quinine's efficacy that gave colonists fresh opportunities to swarm into the Gold Coast, Nigeria and other parts of west Africa..." (Conner pp 95-96 also cites Porter, "The Greatest Benefit to Mankind," pp. 465-466).

Synthetic quinine
Main article: quinine total synthesis
Cinchona trees remain the only practical source of quinine. However, under wartime pressure, research towards its artificial production was undertaken. A formal chemical synthesis was accomplished in 1944 by American chemists R.B. Woodward and W.E. Doering.[1] Since then, several more efficient quinine total syntheses have been achieved[2], but none of them can compete in economic terms with isolation of the alkaloid from natural


http://en.wikipedia.org/wiki/Quinine
 

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Rosalind Franklin
From Wikipedia, the free encyclopedia









 

Rosalind Elsie Franklin (25 July 1920 Notting Hill, London – 16 April 1958 Chelsea, London) was an English biophysicist and X-ray crystallographer who made very important contributions to the understanding of the fine structures of DNA, viruses, coal and graphite. Franklin is best known for her work on the X-ray diffraction images of DNA which were an important influence on Crick and Watson's 1953 hypothesis regarding the structure of DNA. When her work was published it also presented critical evidence in support of their hypothesis. Later she led pioneering work on the tobacco mosaic and polio viruses. She died in 1958 of bronchopneumonia, secondary carcinomatosis, and carcinoma of the ovary; her death certificate read: "A Research Scientist, Spinster, Daughter of Ellis Arthur Franklin, a Banker."
 

Offline Karen W.

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SPLIT PERSONALITY.... more commonly known these days as:

http://en.wikipedia.org/wiki/Dissociative_identity_disorder


Dissociative identity disorder
From Wikipedia, the free encyclopedia
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Dissociative identity disorder
Classification and external resources
ICD-10    F44.8
ICD-9    300.14
MeSH    D009105

Dissociative Identity Disorder, as defined by the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders (DSM), is a psychiatric diagnosis that describes a condition in which a single person displays multiple distinct identities or personalities, each with its own pattern of perceiving and interacting with the environment.[1] The diagnosis requires that at least two personalities routinely take control of the individual's behavior with an associated memory loss that goes beyond normal forgetfulness; in addition, symptoms cannot be due to substance abuse or medical condition. Earlier versions of the DSM named the condition multiple personality disorder (MPD) and the term is still used by the ICD-10. There is controversy around the existence, possible causes, appearance across cultures, and epidemiology of the condition.
Contents
[hide]

    * 1 Controversy
    * 2 Classification
    * 3 Signs and symptoms
    * 4 Causes
    * 5 Pathophysiology
    * 6 Diagnosis
    * 7 Screening
    * 8 Treatment
    * 9 Prognosis
    * 10 Epidemiology
    * 11 History
    * 12 Cultural references
    * 13 See also
    * 14 Notes
    * 15 Further reading
    * 16 External links

 Controversy;

    Main article: Multiple personality controversy

DID is a controversial diagnosis and condition, with much of the literature on DID being generated and published in North America, to the extent that it was regarded as a phenomenon confined to that continent.[2][3][4] Even within North American psychiatrists, there is a lack of consensus regarding the validity of DID,[5][6] with some researchers considering it a culture bound, iatrogenic condition[4][7] though this idea is neither confirmed nor has been accepted by many researchers in the field. [8][9][10][11][12][13] The DSM is explicit about the controversy over the condition, identifying both the objective evidence of physical and sexual abuse in the history of individuals diagnosed with DID and that individuals accused of abuse are motivated to deny or distort past actions, but also points out that childhood memories may be distorted, and that individuals with DID are highly hypnotizable and unusually vulnerable to suggestion.[1] Practitioners who accept DID as a valid disorder have produced an extensive amount of literature, and research originating outside North America has appeared in recent years that documents the epidemiology of the condition in a far greater variety of countries and cultures. Scientific interest in DID peaked in the mid 1990s, then sharply declined, and may now not have widespread scientific acceptance.[14]


Some believe that DID should be re-classified as a trauma disorder.[15]

[edit] Signs and symptoms

Individuals with DID demonstrate a variety of symptoms with wide fluctuations across time; functioning can vary from severe impairment in daily functioning to normal or high abilities. Symptoms can include:[16]

    * multiple mannerisms, attitudes and beliefs that are dissimilar to each other
    * headaches and other body pains
    * distortion or loss of subjective time
    * depersonalization
    * amnesia
    * depression

Patients may experience an extremely broad array of other symptoms that resemble epilepsy, schizophrenia, anxiety, Mood disorders, posttraumatic stress, personality, and eating disorders, with frequent misdiagnoses and ineffective treatment.[16] Patients may experience auditory hallucinations of the various alters conversing, and may be misdiagnosed as psychotic as a result. Changes in identity, loss of memory, and awaking in unexplained locations and situations often leads to chaotic personal lives.[16]
 

Offline neilep

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Traeger,Alfred Hermann OBE (August 2, 1895 – July 31, 1980) was an Australian inventor, chiefly known for the development of the pedal radio.

Traeger was born in Victoria, and raised near Adelaide, South Australia.

He was instrumental in the establishment and early success of the Royal Flying Doctor Service of Australia. Traeger had an interest in radio for much of his life. During the 1920s, he was contacted by Rev John Flynn to assist in experiments which were to enable remote families access to medical treatment by using radio equipment. Since much of remote Australia had no access to electricity, the initial problem was how to provide reliable power to a radio. Traeger consequently developed a pedal generator to power a morse code wireless set.

He made subsequent refinements to this system. A keyboard was developed which enabled unskilled operators to type their message in plain language and have it transmitted in morse. He later developed a voice-capable transceiver.

Due to the success of these inventions, the Traeger Transceivers company was founded, and radios were exported to a number of countries. Traeger was awarded an OBE in 1944.
 

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Uziel Gal
From Wikipedia, the free encyclopedia







Uziel "Uzi" Gal (Hebrew: עוזיאל "עוזי" גל), born Gotthard Glass (December 15, 1923–September 7, 2002), was a German-born- Israeli gun designer best remembered as the designer and namesake of the Uzi submachine gun.

Gal was born in Weimar, Germany. When the Nazis came to power in 1933 he moved first to England and later, in 1936, to Kibbutz Yagur in the British Mandate of Palestine. In 1943 he was arrested for illegally carrying a gun and sentenced to six years in prison. However he was pardoned and released in 1946, serving less than half of his sentence.

Gal began designing the Uzi submachine gun in 1948, shortly after the Israel War of Independence. In 1951 it was officially adopted by the Israeli Defense Force and was called the Uzi after its creator. Gal did not want the weapon to be named after him but his request was ignored. In 1955 he was decorated with Tzalash HaRamatkal and in 1958, Gal was the first person to receive the Israel Security Award, presented to him by Prime Minister David Ben-Gurion for his work on the Uzi.

In 1975 Gal retired from the IDF, and the next year he moved to Philadelphia, Pennsylvania, so that his daughter Tamar, who had serious brain damage, could receive special medical attention.

Gal continued his work as a firearms designer until his death from cancer in 2002.
 

Offline Karen W.

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Vicodin = is a pain medication which is 5mg hydrocodone and 500mg Tylenol when the Hydrocodone is upped and the Tylenol bumped down it is  called "Norco" which comes in a 10mg Hydrocodone and a 325mg Tylenol!
 

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Wankel engine
From Wikipedia, the free encyclopedia





The Wankel engine is a type of internal combustion engine which uses a rotary design to convert pressure into a rotating motion instead of using reciprocating pistons. Its four-stroke cycle is generally generated in a space between the inside of an oval-like epitrochoid-shaped housing and a roughly triangular rotor. This design delivers smooth high-rpm power from a compact, lightweight engine.

The engine was invented by German engineer Felix Wankel. He began its development in the early 1950s at NSU Motorenwerke AG (NSU) before completing a working, running prototype in 1957. NSU then subsequently licenced the concept to other companies across the globe, who added more efforts and improvements in the 1950s and 1960s.

Because of their compact, lightweight design, Wankel rotary engines have been installed in a variety of vehicles and devices such as automobiles and racing cars, aircraft, go-karts, personal water crafts, and auxiliary power units.
 

Offline Alan McDougall

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Lithium to get a little off topic was a godsendfor sufferers of sever bipolar like me.

As a medicine it helped me return to a fairly normal existence. It is toxic and the blood levels must be carefully monitored
 

Offline neilep

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Lithium to get a little off topic was a godsendfor sufferers of sever bipolar like me.

As a medicine it helped me return to a fairly normal existence. It is toxic and the blood levels must be carefully monitored

You describe it in the past tense !...does this mean you are better ?..cured ?....on different meds now ?

Thank you for your contributions Alan !
 

Offline neilep

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 Xing ,Yi (Chinese: 一行; pinyin: Yī Xíng; Wade-Giles: I-Hsing, 683–727), born Zhang Sui (张遂), was a Chinese astronomer, mathematician, mechanical engineer, and Buddhist monk of the Tang Dynasty (618–907). His astronomical celestial globe was the first to feature a clockwork escapement mechanism, the first in a long tradition of Chinese astronomical clockworks.


 

Offline Carolyn

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James Whitney Young (January 24, 1941) was born in Portland, Oregon, and is currently the resident astronomer of the Jet Propulsion Laboratory's Table Mountain Observatory (TMO) near Wrightwood, California having been with them for 45 years. A very prolific asteroid observer of both physical properties and astrometric positions, he has discovered some 390 main belt asteroids in the last six years, as well as two NEOs, 2003 BV35 and 2003 RW11, two Trojan asteroids, 2002 VQ and 2003 FE42, three Mars crossers, 2005 SA, 2005 SB, and 2007 WX3, and one extra-galactic supernova, SN 2005eg.

 

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Ahmed Hassan Zewail (Arabic: أحمد حسن زويل) (born February 26, 1946 in Damanhur, Egypt) is an Egyptian American scientist, and the winner of the 1999 Nobel Prize in Chemistry for his work on femtochemistry.

Femtochemistry
is the science that studies chemical reactions on extremely short timescales, approximately 10–15 seconds (this is one femtosecond, hence the name).

In 1999, Ahmed H. Zewail received the Nobel Prize in Chemistry for his pioneering work in this field.

Zewail’s technique uses flashes of laser light that last for a few femtoseconds. Femtochemistry is the area of physical chemistry that addresses the short time period in which chemical reactions take place and investigates why some reactions occur but not others. Zewail’s picture-taking technique made possible these investigations. One of the first major discoveries of femtochemistry was to reveal details about the intermediate products that form during chemical reactions, which cannot be deduced from observing the starting and end products. Many publications have discussed the possibility of controlling chemical reactions by this method, but this remains controversial.

The simplest approach and still one of the most common techniques is known as pump-probe spectroscopy. In this method, two or more optical pulses with variable time delay between them are used to investigate the processes happening during a chemical reaction. The first pulse (pump) initiates the reaction, by breaking a bond or exciting one of the reactants. The second pulse (probe) is then used to interrogate the progress of the reaction a certain period of time after initiation. As the reaction progresses, the response of the reacting system to the probe pulse will change. By continually scanning the time delay between pump and probe pulses and observing the response, workers can follow the progress of the reaction in real time.
 

Offline Karen W.

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Aberration of light

An annual apparent shift in the positions of stars against the background of more distant stars,
caused by the earth's orbital motion. The shift appears as a circle, an ellipse or even a short line, depending on the distance of the star above or below the earth's orbital plane.

[size=07pt](taken from Colan A. Ronan "the universe the cosmos explained" Glossary)[/size]
« Last Edit: 09/07/2008 14:33:41 by Karen W. »
 

Offline neilep

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Bullocks !

A bullock is a bull which has been castrated !



Here are a load of Bullocks !





 

Offline neilep

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A cyst is a closed sac having a distinct membrane and division on the nearby tissue. They may contain air, fluids, or semi-solid material. A collection of pus is called an abscess, not a cyst. Once formed, the cyst could go away by itself or will have to be removed using surgery.
 

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The Doppler effect (or Doppler shift), named after Christian Doppler, is the change in frequency and wavelength of a wave for an observer moving relative to the source of the waves. It is commonly heard when a vehicle sounding a siren approaches, passes and recedes from an observer. The received frequency is higher than the emitted frequency when the siren approaches, is equal to the emitted frequency as it passes the observer and is lower than the emitted frequency as it recedes from the observer.

For waves that propagate in a medium, such as sound waves, the velocity of the observer and of the source are relative to the medium in which the waves are transmitted. The total Doppler effect may therefore result from motion of the source, motion of the observer, or motion of the medium. Each of these effects is analysed separately. For waves which do not require a medium, such as light or gravity in special relativity, only the relative difference in velocity between the observer and the source needs to be considered.


A source of waves moving to the left.
The frequency is higher on the left than
on the right.



 

Offline H2O2

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X is for xylem tissue, found in a plants vascular system, used to transport water and solutes.
 

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X is for xylem tissue, found in a plants vascular system, used to transport water and solutes.

Brilliant post H202...but if ewe look closely that each post is sequential in the alphabet...ie: this one that ewe just posted should have started with an ' E' to follow on from the ' D ' of Doppler !

Wanna try again ?....good on ya and no worries. thanks for your contribution!
 

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Etymology
From Wikipedia, the free encyclopedia

Etymology is the study of the history of words —(The history of these words date as far back as two minutes ago)  ;D) when they entered a language, from what source, and how their form and meaning have changed over time.

In languages with a long detailed history, etymology makes use of philology, the study of how words change from culture to culture over time. However, etymologists also apply the methods of comparative linguistics to reconstruct information about languages that are too old for any direct information (such as writing) to be known. By analyzing related languages with a technique known as the comparative method, linguists can make inferences, about their shared parent language and its vocabulary. In this way, word roots have been found which can be traced all the way back to the origin of, for instance, the Indo-European language family.

Even though etymological research originally grew from the philological tradition, nowadays much etymological research is done in language families where little or no early documentation is available, such as Uralic and Austronesian.

 

Offline rosalind dna

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Filament Propagation


(Wiki)

In nonlinear optics, filament propagation is propagation of a beam of light through a medium without diffraction. This is possible because the Kerr effect causes an index of refraction change in the medium, resulting in self-focusing of the beam.

Filament propagation of laser pulses in the atmosphere was observed in 1994 by Gérard Mourou and his team at University of Michigan. The balance between the self-focusing refraction and self-attenuating diffraction by ionization and rarefaction of a laser beam of terawatt intensities, created by chirped pulse amplification, in the atmosphere creates "filaments" which act as waveguides for the beam thus preventing divergence. If a light filament drops below the intensity needed for this dynamic balance, called modulation instability, it can merge with another filament and continue propagating without broadening as with all earlier means of sending light. The filaments, having made a plasma, turn the narrowband laser pulse into a broadband pulse having a wholly new set of applications.

Filament propagation in a semiconductor medium can also be observed in large aperture vertical cavity surface emitting

In nonlinear optics, filament propagation is propagation of a beam of light through a medium without diffraction. This is possible because the Kerr effect causes an index of refraction change in the medium, resulting in self-focusing of the beam.

Filament propagation of laser pulses in the atmosphere was observed in 1994 by Gérard Mourou and his team at University of Michigan. The balance between the self-focusing refraction and self-attenuating diffraction by ionization and rarefaction of a laser beam of terawatt intensities, created by chirped pulse amplification, in the atmosphere creates "filaments" which act as waveguides for the beam thus preventing divergence. If a light filament drops below the intensity needed for this dynamic balance, called modulation instability, it can merge with another filament and continue propagating without broadening as with all earlier means of sending light. The filaments, having made a plasma, turn the narrowband laser pulse into a broadband pulse having a wholly new set of applications.

Filament propagation in a semiconductor medium can also be observed in large aperture vertical cavity surface emitting

http://en.wikipedia.org/wiki/Filament_propagation
 

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