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nuclear winter

(Encyclopedia)nuclear winter, theory holding that the smoke and dust produced by a large nuclear war would result in a prolonged period of cold on the earth. The earliest version of the theory, which was put forwar...

obsidian

(Encyclopedia)obsidian ŏbsĭdˈēən [key], a volcanic glass, homogeneous in texture and having a low water content, with a vitreous luster and a conchoidal fracture. The color is commonly black, but may be some s...

lignite

(Encyclopedia)lignite lĭgˈnīt [key] or brown coal, carbonaceous fuel intermediate between coal and peat, brown or yellowish in color and woody in texture. It contains more moisture than coal and tends to dry and...

mammography

(Encyclopedia)mammography, diagnostic procedure that uses low-dose X rays to detect abnormalities in the breasts. Tomosynthesis, also known as 3D mammography, is form of mammography that combines X-ray images taken...

kame

(Encyclopedia)kame kām [key], low, steep, rounded hill or ridge of layered sand and gravel drift, developed from glacial deposits. Kames were probably formed by streams of melting glacial ice that deposited mud an...

Waxman, Henry Arnold

(Encyclopedia)Waxman, Henry Arnold, 1939–, U.S. congressman, b. Los Angeles, grad. Univ. of California, Los Angeles. (B.A., 1961; J.D., 1964). After serving (1969–74) in the California state assembly, he won (1...

blackthorn

(Encyclopedia)blackthorn or sloe, low, spreading, thorny bush or small tree (Prunus spinosa) of the plum genus of the family Rosaceae (rose family), having black bark, white flowers, and deep blue fruits, usually r...

Tromelin Island

(Encyclopedia)Tromelin Island trōmlăNˈ [key], c.1 sq mi (2.6 sq km), in the Indian Ocean c.260 mi (420 km) E of Madagascar, part of the Scattered Islands district with the French Southern and Antarctic Lands. A ...

solder

(Encyclopedia)solder sŏdˈər [key], metal alloy used in the molten state as a metallic binder. The type of solder to be used is determined by the metals to be united. Soft solders are commonly composed of lead an...

Schick test

(Encyclopedia)Schick test, diagnostic test designed to evaluate susceptibility to diphtheria. A small amount of diphtheria toxin is injected into the skin; the injection will produce an area of redness and swelling...