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animal-rights movement

(Encyclopedia)animal-rights movement, diverse individuals and groups concerned with protecting animals from perceived abuse or misuse. Supporters are specifically concerned with the use of animals for medical and c...

Anderson, Maxwell

(Encyclopedia)Anderson, Maxwell, 1888–1959, American dramatist, b. Atlantic, Pa., grad. Univ. of North Dakota, 1911. His plays, many of which are written in verse, usually concern social and moral problems. Ander...

Grand Island

(Encyclopedia)Grand Island <1> City (2020 pop. 53,131), seat of Hall co., S Nebr., on the Wood River near its junction with the Platte; settled 1857 on the Plat...

dimension, in mathematics

(Encyclopedia)dimension, in mathematics, number of parameters or coordinates required locally to describe points in a mathematical object (usually geometric in character). For example, the space we inhabit is three...

dissociation

(Encyclopedia)dissociation, in chemistry, separation of a substance into atoms or ions. Thermal dissociation occurs at high temperatures. For example, hydrogen molecules (H2) dissociate into atoms (H) at very high ...

polyhedron

(Encyclopedia)CE5 Polyhedrons polyhedron pŏlˌēhēˈdrən [key], closed solid bounded by plane faces; each face of a polyhedron is a polygon. A cube is a polyhedron bounded by six polygons (in this case squar...

St.-John's-wort

(Encyclopedia)St.-John's-wort, any species of the large and widespread herbaceous or shrubby genus Hypericum of the family Hypericaceae (St.-John's-wort family), usually found in moist, open places and often having...

sabotage

(Encyclopedia)sabotage [Fr., sabot=wooden shoe; hence, to work clumsily], form of direct action by workers against employers through obstruction of work and/or lowering of plant efficiency. Methods range from peace...

Baltimore, David

(Encyclopedia)Baltimore, David bôlˈtĭmôr [key], 1938–, American microbiologist, b. New York City, Ph.D. Rockefeller Univ., 1964. He conducted (1965–68) virology research at the Salk Institute before becomin...

perpetual-motion machine

(Encyclopedia)perpetual-motion machine, device that would be able to operate continuously and supply useful work, in violation of the laws of thermodynamics. A machine that would produce more energy in the form of ...