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myosin

(Encyclopedia)myosin mīˈəsĭn [key], one of the two major protein constituents responsible for contraction of muscle. In muscle cells myosin is arranged in long filaments called thick filaments that lie parallel...

molecular orbital theory

(Encyclopedia)molecular orbital theory, detailed explanation of how electrons are distributed in stable molecules. In the simpler valence theory of the chemical bond, each atom in a molecule is assumed to retain it...

luminosity

(Encyclopedia)luminosity, in astronomy, the rate at which energy of all types is radiated by an object in all directions. A star's luminosity depends on its size and its temperature, varying as the square of the ra...

Mingus, Charles

(Encyclopedia)Mingus, Charles mĭngˈgəs [key], 1922–79, American jazz musician, b. Nogales, Ariz. Mingus was a bassist, pianist, bandleader, composer, and vocalist. He was one of the most important jazz compose...

lactic acid

(Encyclopedia)lactic acid, CH3CHOHCO2H, a colorless liquid organic acid. It is miscible with water or ethanol. Lactic acid is a fermentation product of lactose (milk sugar); it is present in sour milk, koumiss, leb...

Wigner, Eugene Paul

(Encyclopedia)Wigner, Eugene Paul wĭgˈnər [key], 1902–95, American physicist, b. Hungary, grad. Technische Hochschule, Berlin, 1925. He was a professor at Princeton from 1930 to 1936 and again from 1938 to 197...

Wittkower, Rudolf

(Encyclopedia)Wittkower, Rudolf wĭtˈkōv-ər, Ger. vĭtˈkōv-ər [key], 1901–71, German-American art historian. After gaining his doctorate in Berlin, Wittkower became a research assistant and later research f...

bolometer

(Encyclopedia)bolometer bōlŏmˈətər, bə– [key], instrument for detecting and measuring radiation, e.g., visible light, infrared radiation, and ultraviolet radiation, in amounts as small as one millionth of a...

string theory

(Encyclopedia)string theory, description of elementary particles based on one-dimensional curves, or “strings,” instead of point particles. Superstring theory, which is string theory that contains a kind of sym...

Three Mile Island

(Encyclopedia)Three Mile Island, site of a nuclear power plant 10 mi (16 km) south of Harrisburg, Pa. On Mar. 28, 1979, failure of the cooling system of the No. 2 nuclear reactor led to overheating and partial melt...