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behavior therapy

(Encyclopedia)behavior therapy or behavior modification, in psychology, treatment of human behavioral disorders through the reinforcement of acceptable behavior and suppression of undesirable behavior. The techniqu...

sphagnum

(Encyclopedia)sphagnum sfăgˈnəm [key] or peat moss, any species of the large and widely distributed genus Sphagnum, economically the most valuable moss. Sphagnums, the principal constituent of peat, typically gr...

Carver, George Washington

(Encyclopedia)Carver, George Washington, 1864?–1943, American agricultural chemist, b. Diamond, Mo., grad. Iowa State College (now Iowa State Univ.; B.S., 1894; M.A. 1896). Born a slave, he later, as a free man, ...

Richards, I. A.

(Encyclopedia)Richards, I. A. (Ivor Armstrong Richards), 1893–1979, English literary critic. Richards was one of the founders of the school of interpretation known as the New Criticism, which stressed an awarenes...

personal watercraft

(Encyclopedia)personal watercraft (PWC), a lightweight vessel usually less than 16 ft (5 m) long that uses an inboard water jet pump, powered by an internal-combustion engine, as its primary source of propulsion. T...

bellows

(Encyclopedia)bellows, expansible, gas-tight chamber used to pump or store a gas. One of the simplest and most familiar types of bellows is the manual one used for providing a forced draft to a fire. The expansible...

microscope

(Encyclopedia)CE5 Compound microscope microscope, optical instrument used to increase the apparent size of an object. The electron microscope, which is not limited by the powers of optical lenses and light,...

du Vigneaud, Vincent

(Encyclopedia)du Vigneaud, Vincent dyo͞o vēnˈyō [key], 1901–78, American biochemist, b. Chicago. He was professor of biochemistry and head of the department at George Washington Univ. school of medicine (1932...

Dale, Sir Henry Hallett

(Encyclopedia)Dale, Sir Henry Hallett, 1875–1968, English scientist. For his study of acetylcholine as agent in the chemical transmission of nerve impulses he shared with Otto Loewi the 1936 Nobel Prize in Physio...

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