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anaphylaxis

(Encyclopedia)anaphylaxis ănˌəfəlăkˈsĭs [key], hypersensitive state that may develop after introduction of a foreign protein or other antigen into the body tissues. When an anaphylactic state exists, a secon...

Durham, city, United States

(Encyclopedia)Durham dûrˈăm [key], city (2020 pop. 324,833), seat of Durham co., N central N.C., in the ...

semiconductor

(Encyclopedia)CE5 N-type and P-type crystals: In a pure silicon crystal each silicon atom (Si) is surrounded by four valence electrons. In the N-doped semiconductor, illustrated in the left-hand figure, some sil...

acids and bases

(Encyclopedia)acids and bases, two related classes of chemicals; the members of each class have a number of common properties when dissolved in a solvent, usually water. Another theory that provides a very broad ...

Kondylis, George

(Encyclopedia)Kondylis, George kônᵺēˈlĭs [key], 1879–1936, Greek general and statesman. He fought in the Balkan Wars and at Salonica in World War I. Entering politics in the turbulent postwar years, he serv...

Dayan, Moshe

(Encyclopedia)Dayan, Moshe mōˈshə dīänˈ, däyänˈ [key], 1915–81, Israeli military leader, b. Palestine. After attending Senior Agricultural School in Nahalal, Dayan fought with the Haganah (Jewish militia...

Fort Necessity

(Encyclopedia)Fort Necessity, entrenched camp built in July, 1754, by George Washington and his Virginia militia at Great Meadows (near the present Uniontown, Pa.). He retired there when he learned that the British...

Ibadan

(Encyclopedia)Ibadan ēbäˈdän, ēbädäNˈ [key], city (1991 est. pop. 1,263,000), SW Nigeria. The second largest city in Nigeria, it is a major commercial center. Manufactures include metal products, furniture,...

Bougainville, Louis Antoine de

(Encyclopedia)Bougainville, Louis Antoine de lwē äNtwänˈ də bo͞ogăNvēlˈ [key], 1729–1811, French navigator. He accompanied Montcalm to Canada as aide-de-camp, and he later (c.1764) established a colony o...

dictator

(Encyclopedia)dictator, originally a Roman magistrate appointed to rule the state in times of emergency; in modern usage, an absolutist or autocratic ruler who assumes extraconstitutional powers. From 501 b.c. unti...