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Mastigophora
(Encyclopedia)Mastigophora măsˌtĭgŏfˈərə [key], phylum of unicellular heterotrophic protozoans of the kingdom Protista. Most of the approximately 1,500 species of Mastigophora are propelled by one or more fl...Weinberg, Steven
(Encyclopedia)Weinberg, Steven, 1933–, American nuclear physicist, b. New York City, Ph.D. Princeton, 1957. Since 1982 he has been a professor at the Univ. of Texas at Austin, having previously been on the facult...arc, in electricity
(Encyclopedia)arc, in electricity, highly luminous and intensely hot discharge of electricity between two electrodes. The arc was discovered early in the 19th cent. by the English scientist Sir Humphry Davy, who so...motion
(Encyclopedia)motion, the change of position of one body with respect to another. The rate of change is the speed of the body. If the direction of motion is also given, then the velocity of the body is determined; ...thermionic emission
(Encyclopedia)thermionic emission thûrmˌīŏnˈĭk [key], emission of electrons or ions by substances that are highly heated, the charged particles being called thermions. The number of thermions emitted increase...sand dollar
(Encyclopedia)sand dollar, common name for a marine animal in the same phylum as the starfish (see sea star). The sand dollar has a rigid, flattened, disk-shaped test, or shell, made of firmly united plates lying j...harmony
(Encyclopedia)harmony, in music, simultaneous sounding of two or more tones and, especially, the study of chords and their relations. Harmony was the last in the development of what may be considered the basic elem...Durkheim, Émile
(Encyclopedia)Durkheim, Émile dûrkˈhīm, Fr. āmēlˈ dürkĕmˈ [key], 1858–1917, French sociologist. Along with Max Weber he is considered one of the chief founders of modern sociology. Educated in France an...Maxwell, James Clerk
(Encyclopedia)Maxwell, James Clerk klärk [key], 1831–79, great Scottish physicist. After a brilliant career at Edinburgh and Cambridge, where he won early recognition with mathematical papers, he was a professor...PET scan
(Encyclopedia)PET scan pŏzˈĭtrŏnˌ ĭmĭshˈən təmŏgˈrəfē [key], a medical imaging technique that monitors metabolic, or biochemical, activity in the brain and other organs by tracking the movement and co...Browse by Subject
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