Biographical encyclopedia
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666 [1055] TWORT
RUSSELL [1056] unimportant adjunct of the proteins that served as the basis of genetics. Now it seemed that it was DNA that was the real thing. This led directly to a new assault on DNA and the discovery of its structure and its mode of replication by Crick [1406] and James Dewey Watson [1480].
[1055] TWORT, Frederick William English bacteriologist Born: Camberley, Surrey, Octo ber 22, 1877 Died: Camberley, March 20, 1950 Twort, the son of a physician, ob tained a medical degree in 1900. As a professor of bacteriology at the Univer sity of London, Twort discovered in 1915 a type of virus that infested and killed bacteria. The discovery was made independently a couple of years later by D’Herelle [1012], who named the viruses bacteriophages (“bacteria eat ers”). There were some rather unsavory disputes concerning precedence, but it was the bacteriophages themselves that proved important, whoever discovered them. Although they made the tiniest cells their prey, they were themselves larger and more complicated in structure than the average virus, and therefore more in teresting to study. In the decade follow ing Twort’s death, the bacteriophages, studied by men like Fraenkel-Conrat [1355], yielded a number of the secrets of viral structure and action. [1056] RUSSELL, Henry Norris American astronomer Born: Oyster Bay, New York, October 25, 1877 Died: Princeton, New Jersey, February 18, 1957 Russell, the son of a minister who had emigrated from Canada, was educated at Princeton University, obtaining his doc torate in 1900. After postdoctoral work in England, he returned to teach at Princeton in 1905 and in 1912 became the director of the university’s observa tory. In 1921 he began an association with Mount Wilson Observatory that continued till his retirement. In 1914 Russell published his observa tions of a certain regularity he had dis covered in the relationship between the brightness of stars, their color, and their spectral class. It was to be expected that red stars were cooler than yellow stars, which were in turn cooler than blue- white stars. The work of Wien [934] twenty years earlier had made that clear. In that case, then, red stars, as the coolest and least luminous, ought to be the dimmest. Some were. Other red stars, however, were quite bright. The only way a cool red star could be very lumi nous is to suppose it to be very large so that although its surface radiates little light per unit area, there is a great deal of radiating area, giving rise to a large total radiation. Thus there were red gi ants and red dwarfs. Russell could find no red star of intermediate size. To a less marked extent, there were yellow giants and yellow dwarfs, our own sun being a yellow dwarf. In fact, if the spectral class (which dictates the color of the star) is plotted against the luminosity, the stars fall in a diagonal line, from the red dwarfs of spectral class K, at the lower right, to the blue-whites of spectral class O at the upper left, with the giant and supergiant stars making a horizontal line at the top. This same fact had been discovered some years earlier by Hertzsprung [1018], so the plot is usually called the Hertzsprung-Russell diagram. It is very tempting, from this diagram, to deduce that stars are following a definite life cycle. The simplest picture, and the one presented by Russell, and before him by Lockyer [719] in 1890, is that as a quan tity of gas contracts, it begins to heat up and radiate in the red, at which time it is a red giant. It continues to contract and heats further, becoming a smaller, but hotter and brighter yellow giant, then a still smaller but still hotter and brighter blue-white star. In doing this, the star is pictured as traveling along the horizontal
[1057] WATSON
NIEUWLAND [1058] bar on top of the Hertzsprung-Russell di agram. Thereafter, it descends the diagonal line, cooling down as it shrinks further, becoming a yellow dwarf, then a red dwarf, and finally a black cinder. From this viewpoint, our sun is past its best days and is on its way down to extinc tion, though still good for billions of years. This was the first reasonably good at tempt to work out the evolutionary life cycle of stars. It came, however, before the nuclear mechanisms of stellar energy formation had been worked out a quar ter century later by men like Bethe [1308]. Once that was done, Russell’s evolutionary scheme proved far too sim ple and was abandoned. Nevertheless, the diagonal line of stars in the diagram still has its significance even in modern schemes of stellar evolution and is re ferred to as the Main sequence. In 1929 Russell analyzed the sun’s spectrum and worked out its composition in detail. Rather surprisingly the sun proved to be largely hydrogen with he lium, oxygen, nitrogen, and neon the most important of the minor constit- utents. Stars generally proved to be mostly hydrogen and the universe itself is thought to be mainly hydrogen and helium in a 9-1 ratio. Russell, in 1927, published an astron omy text that, for the first time shifted the main emphasis from the solar system and celestial mechanics to the stars and astrophysics. [1057] WATSON, John Broadus American psychologist
January 9, 1878 Died: New York, New York, September 25, 1958 Watson obtained his Ph.D. at the Uni versity of Chicago in 1903 and joined its faculty that same year. In 1908 he was appointed professor of experimental and comparative psychology at Johns Hop kins.
Watson carried on intensive experi ments in animal behavior and was ex tremely interested in the conditioned re sponses described by Pavlov [802]. In studying animals, there is no question of penetrating motivation, of making use of introspection to enter the unconscious; only the actual behavior can be ob served. Watson transferred this view to the study of human psychology. He took a position directly contrary to Freud [865] and the various schools de scended from that Austrian’s psycho analytic teachings. In 1913 Watson pub lished an article that served to found the behaviorist school of psychology. Watson believed that human behavior was ex plainable in terms of conditioned re sponses and relegated even heredity to a minor role. Animals, including the human being, were viewed as intensely complicated machines, who reacted ac cording to their nerve-path “wiring,” these nerve paths being altered, or condi tioned, by experience. These views are far too extreme for most psychologists today, but no doubt they serve as a use ful corrective for the ultra-Freudians and Jungians who tend to rise on wings of words into the semimystical. In addition, the observations of men such as Gesell [1070] do lend a certain mechanistic pa tina to the development of human chil dren.
In 1924 Watson left the academic world for an executive position in an ad vertising firm. However, advertising is certainly applied psychology, if anything is, so the move was by no means as radi cal as it might seem. [1058] NIEUWLAND, Julius Arthur (nyoo'land) Belgian-American chemist
Belgium, February 14, 1878 Died: Washington, D.C., June 11, 1936
Nieuwland was brought to the United States by his parents when he was three years old. The family settled in South Bend, Indiana, and young Nieuwland, after an education in the parochial 6 6 8
[1058] NIEUWLAND w h ip p l e
school system, attended the University of Notre Dame from which he graduated in 1899. He studied for the priesthood, to which he was ordained in 1903. This did not prevent him from also studying chemistry and botany, and he was awarded his doctor’s degree in 1904 at Catholic University. His scientific life shows a progress from botany to chemistry, for he was professor of botany at Notre Dame from 1904 to 1918, and professor of chemis try there from 1918 to his death. It is for his chemical researches, however, that he is best remembered. His doctoral dissertation dealt with the reactions of acetylene and that remained his prime interest. One of the products he had obtained in the course of this doctoral research was divinylchlorarsine, a compound he described but with which he refused to work because of its ex tremely poisonous nature. Perhaps his in tuition guided him here, for when its properties were further studied over a decade later, it gained considerable noto riety. It was renamed Lewisite, after the army chemist who devised methods of preparing it, and it proved a worse poi son gas than any of those used in World War I. Fortunately, it was not prepared in quantity until the very month of the Armistice, and what had been made ready was eventually destroyed at sea. In 1906 Nieuwland, in continuing his studies on acetylene, detected a strange odor. For fourteen years he tracked down that odor and in 1920 identified the compounds giving rise to it. He found that acetylene, a compound with a molecule containing two carbon atoms, could be made to combine with itself to form a four-carbon molecule and a six- carbon molecule. These larger molecules could continue to add on two-carbon units (polymerizing) forming a giant molecule that had some of the properties of rubber. This attracted the attention of chem ists at Du Pont, with whom Nieuwland worked closely thereafter. Under the leadership of Carothers [1190], who was later to prepare nylon, it was found that if a chlorine atom was added at the four- carbon stage, the final polymer was much more like rubber. It was, in fact, what is now called neoprene, one of the early synthetic rubbers. When lapan cut off the supply of natural rubber during the tragic months after Pearl Harbor, it was synthetic rubber that kept essential facets of the American economy rolling. Neither Nieuwland nor Carothers long survived the development of neoprene, however, or lived to see its conse quences.
[1059] WHIPPLE, George Hoyt American physician Born: Ashland, New Hampshire, August 28, 1878 Died: Rochester, New York, Feb ruary 1, 1976 Whipple graduated from Yale Univer sity in 1900 and received his medical de gree in 1905 from Johns Hopkins Uni versity. After a stay in the Panama Canal Zone and some years of training and teaching at Johns Hopkins he went to California in 1914 as professor of medicine at the University of California. In 1921 he went to the University of Rochester where he organized its new medical school, serving as its first dean, and retaining that position till 1953. He was primarily interested in bile pig ments, as were Pregl [982] and Wieland [1048], but for Whipple the problem led in a third direction. Since bile pigments are formed in the body from hemoglo bin, Whipple thought he ought to tackle the methods by which hemoglobin was handled by the body, beginning with its formation. He therefore began a series of experi ments in 1917 in which he bled dogs to introduce an anemia, and then followed the manner in which new red blood cor puscles were formed. He kept dogs on various kinds of diet to see what effect that would have on corpuscle formation and found that liver was the most potent item of those he tried. This paved the way for the successful treament of perni cious anemia by Minot [1103] and Murphy [1154] and so he shared with
[1060] MEITNER
BR0NSTED [1061] them the 1934 Nobel Prize in medicine and physiology. [1060] MEITNER, Lise (mite'ner) Austrian-Swedish physicist
ber 27, 1968 Meitner, the daughter of a lawyer, was of Jewish descent but was baptized in in fancy and was raised as a Protestant. She grew interested in science when she read of the Curies’ [897, 965] discovery of radium in 1902. She studied at the University of Vienna under Boltzmann [769], among others, obtaining her doc torate in 1906. She visited Berlin in 1907 in order to attend the lectures of Max Planck [887] and stayed to join Otto Hahn [1063] in a research collaboration that lasted thirty years. She had to battle a comically stu pid prejudice against women scientists on the part of the German professors. Emil Fischer [833] allowed her to work for him only after she promised never to enter laboratories where males were working (though eventually he gave in and allowed her to enter the sacred pre cincts). During World War I she patriot ically served as a nurse in the Austrian army.
During the first years of Hitler’s re gime, she was safe from harm, though of Jewish descent, because she was an Aus trian national. After the Nazi absorption of Austria in 1938, however, she was forced to leave Germany. Through the help of Debye [1094] and Coster [1135], she managed to enter the Netherlands without a visa. She then went to Bohr [1101] in Denmark and finally to Stock holm, where Bohr helped get her a posi tion with Siegbahn [1111]. She was more firmly convinced than Hahn of the actuality of uranium fission and it was from Stockholm, in January 1939, that she published the first report concerning it. She visited the United States after World War II, then returned to Sweden, becoming a Swedish citizen in 1949. She moved on to Cambridge in 1960, and in 1966 she was awarded a share of the Fermi Award issued by the Atomic Energy Commission. She was the first woman to win the award. She died just short of her ninetieth birthday, and outlived her long-time friend and associate, Hahn, by just three months. Her devotion to science had been total. She never married. [1061] BR0NSTED, Johannes Nicolaus (brun'sted) Danish chemist
22, 1879 Died: Copenhagen, December 17, 1947
Brpnsted’s father (who died when Brpnsted was thirteen) had been a civil engineer and at first Brpnsted himself was slated for the same profession. How ever, he was interested in chemistry and in college switched to that subject. In 1908 he earned his doctorate at the Copenhagen Polytechnic Institute and was selected for a new professorship of chemistry instituted at the University of Copenhagen. Brpnsted interested himself in chemi cal thermodynamics, his fundamental contributions rivaling those of G. N. Lewis [1037]. He also produced experi mental work that confirmed the theories of Debye [1094] concerning ionic sub stances in solution. Br0nsted’s studies of how acids and bases catalyzed reactions, begun in 1921, forced him to clarify just what acids and bases were. The classic definition was that acids were substances that gave up hydrogen ions in solution, while bases gave up hydroxyl ions. Since the proper ties of acids and bases were in so many respects opposed to each other, Brpnsted believed that it would make far more sense to supply definitions that were op posed to each other. In 1923, therefore, Brpnsted suggested that if acids were substances that gave up a hydrogen ion in solution, bases must be substances that took up a hydro gen ion in solution. This left the hy droxyl ion a strong base, since it cer 670 [1062] MCCOLLUM
MCCOLLUM [1062] tainly reacted with the hydrogen ion, taking it up to form water. However, the base concept was most usefully broad ened to include many substances other than hydroxyl ion. In fact, the connection between acids and bases was clarified, since every acid, in giving up a hydrogen ion, became a base, with the capacity of taking up a hydrogen ion once more to form the acid again. Thus, rather than a set of acids and a set of bases with no neces sary connection, there was one set of conjugate acid-base systems. The new view is the one most com monly used in chemical thinking now, al though Lewis introduced a still broader concept of acids and bases. After World War n, during which Brpnsted distinguished himself by his firm anti-Nazi attitude, he was elected to the Danish parliament in 1947 but died before he could take his seat. [1062] McCOLLUM, Elmer Vemer American biochemist Born: near Fort Scott, Kansas, March 3, 1879 Died: Baltimore, Maryland, No vember 15, 1967 McCollum studied at the University of Kansas, graduating in 1903, then going on to earn his doctorate at Yale Univer sity in 1906. He joined the faculty of the University of Wisconsin in 1907, but went to Johns Hopkins University in 1917 as professor of biochemistry, the first faculty member in its School of Hy giene and Public Health. There he re mained till his retirement in 1946. McCollum’s prime interest was in diet and he continued the attempt, earlier carried on by men like Hopkins [912], to find a way to nourish and support ani mals on a mixture of simple substances. (He popularized the use of the white rat as an experimental animal.) Through his early years at Wisconsin he failed, even though he tried to flavor his mixture in various ways, just in case it was the in sipidity of the food rather than its chem ical insufficiency that bothered the exper imental animals. Some admixture of nat ural food, however, continued to be re quired no matter what he did. The work of Eijkman [888] was filter ing into the biochemical consciousness at the time and Hopkins’ notion of the vita min concept was reinforced by Funk [1093]. It began to appear that it was not the natural food that was required to supplement the diet, but the vitamin con tent thereof, additional simple substances essential to life in very small quantities. McCollum started trying to locate these. In 1913 McCollum and his colleagues discovered that a factor essential to life was present in some fats. This had to be chemically different from the factor studied by Eijkman, which was soluble in water. McCollum spoke of fat-soluble A and water-soluble B and this soon be came vitamin A and vitamin B, the first of a host of lettered vitamins. These let ters survived a quarter of a century until increasing knowledge of the chemical na ture of the vitamins allowed the use of proper chemical names. The letters are still used in popular articles and discus sions.
Later, McCollum contributed tp the discovery of other fat-soluble vitamins, such as vitamin D in 1922, and vitamin E still later. (The letter C was already assigned to the factor whose absence caused scurvy, and whose existence in the citrus fruits used by Lind [288] cured the disease a century and a half earlier.) Knowledge of the water-soluble vita mins was being extended in the 1920s also, by men like Goldberger [1027], Methods for assaying various foods for vitamin content, so that diets could be rationalized in the light of the new knowledge, were developed by Sherman [1036], McCollum also did important work in the field of trace minerals. These were inorganic elements which, like the or ganic vitamins, were necessary to life in small quantities. McCollum showed that a deficiency of calcium in the body would eventually produce tetany, that is, muscular spasm. He also showed that the body required no phosphorus-containing organic materials, of the type first re ported by Harden [947], in the diet. It Download 17.33 Mb. Do'stlaringiz bilan baham: 
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