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heart, artificial

(Encyclopedia)heart, artificial, external or surgically implanted mechanical device designed to replace a patient's diseased heart. The first one used on a human being, the Jarvik-7, was implanted (1982) in Barney ...

heating

(Encyclopedia)CE5 Typical warm-air heating system heating, means of making a building comfortably warm relative to a colder outside temperature. Old, primitive methods of heating a building or a room within it ...

symmetry

(Encyclopedia)symmetry, generally speaking, a balance or correspondence between various parts of an object; the term symmetry is used both in the arts and in the sciences. In art and design, it is often used in a s...

bubble chamber

(Encyclopedia)bubble chamber, device for detecting charged particles and other radiation by means of tracks of bubbles left in a chamber filled with liquid hydrogen or other liquefied gas. It was invented in 1952 b...

cave

(Encyclopedia)cave, a cavity in the earth's surface usually large enough for a person to enter. Caves may be formed by the chemical and mechanical action of a stream upon soluble or soft rock, of rainwater seeping ...

Michelangelo Buonarroti

(Encyclopedia)Michelangelo Buonarroti mīkəlănˈjəlō, Ital. mēkālänˈjālō bwōnär-rôˈtē [key], 1475–1564, Italian sculptor, painter, architect, and poet, b. Caprese, Tuscany. In his architectura...

chemical bond

(Encyclopedia)chemical bond, mechanism whereby atoms combine to form molecules. There is a chemical bond between two atoms or groups of atoms when the forces acting between them are strong enough to lead to the for...

Freud, Sigmund

(Encyclopedia)Freud, Sigmund froid [key], 1856–1939, Austrian psychiatrist, founder of psychoanalysis. Born in Moravia, he lived most of his life in Vienna, receiving his medical degree from the Univ. of Vienna i...

neutrino astronomy

(Encyclopedia)neutrino astronomy, study of stars by means of their emission of neutrinos, fundamental particles that result from nuclear reactions and are emitted by stars along with light. Approximately 100 billio...

Safavid

(Encyclopedia)Safavid säfäˈwēd [key], Iranian dynasty (1499–1736), that established Shiite Islam in Iran as an official state religion. The Safavid state provided both the territorial and societal foundations...