(1890-1967) US geneticist who discovered 1926 that mutations can be artificially induced by X-rays. This showed that mutations are nothing more than chemical changes. He was awarded the Nobel Prize for Physiology or Medicine 1946.
Muller campaigned against the needless use of X-rays in diagnosis and treatment, and pressed for safety regulations to ensure that people who were regularly exposed to X-rays were adequately protected. He also opposed nuclear-bomb tests.
Muller was born in New York and studied at Columbia. In 1920 he joined the University of Texas, Austin, later becoming professor of zoology. The constraints on his freedom to express his socialist political views caused him to leave the US 1932, and from 1933 he worked at the Institute of Genetics in the USSR. But the false ideas of Trofim Lysenko began to dominate Soviet biological research; openly critical of Lysenkoism, Muller was forced to leave in 1937. After serving in the Spanish Civil War, he worked at the Institute of Animal Genetics in Edinburgh. In 1940 he returned to the US, becoming professor at Indiana University 1945.
In 1919 Muller found that the mutation rate was increased by heat, and that heat did not always affect both of the chromosomes in a chromosome pair. From this he concluded that mutations involved changes at the molecular or submolecular level. Next he experimented with X-rays as a means of inducing mutations, and by 1926 he had proved the method successful.
Muller's research convinced him that almost all mutations are deleterious. In the normal course of evolution, deleterious mutants die out and the few advantageous ones survive, but he believed that if the mutation rate is too high, the number of imperfect individuals may become too large for the species as a whole to survive. + prikaži više

1. Metal secured to a carriage is fed against rotating cutters that shape it; SYN. milling machine.
2. Someone who works in a mill (especially a grain mill).

(1929-) German dramatist. His scripts have played a leading role in contemporary avant-garde theater in Germany and abroad. Early political works, showing the influence of Brecht, (The Scab 1950, The Correction 1958) were followed by Mauser 1970, Cement 1972 (on the Russian revolution), Hamletmachine 1977, and Medea-material 1982.
He collaborated closely with the American director Robert Wilson during the 1980s. + prikaži više

(1801-1858) German comparative anatomist whose studies of nerves and sense organs opened a new chapter in physiology by demonstrating the physical nature of sensory perception. His name is associated with a number of discoveries, including the Müllerian ducts in the mammalian fetus and the lymph heart in frogs.

Karl Alexander 1927- Swiss physicist

(1899-1965) Swiss chemist who discovered the first synthetic contact insecticide, DDT, 1939. For this he was awarded a Nobel Prize 1948.
Müller was born in Olten, Solothurn, and studied at Basel. He went to work for the chemical firm of J R Geigy, researching principally into dyestuffs and tanning agents; he subsequently joined the staff of Basel University.
In 1935, Müller started the search for a substance that would kill insects quickly but have little or no poisonous effect on plants and animals, unlike the arsenical compounds then in use. He concentrated his search on chlorine compounds and in 1939 synthesized DDT.
The Swiss government successfully tested DDT against the Colorado potato beetle in 1939 and by 1942 it was in commercial production. Its first important use was in Naples, Italy, where a typhus epidemic 1943–44 was ended when the population was sprayed with DDT to kill the body lice that are the carriers of typhus. + prikaži više