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Nogales
Nogales , city (1990 pop. 19,489), Santa Cruz co., S Ariz. on the Mexican border with its adjacent city, Nogales (1990 pop. 105,873), Sonora, NW Mexico. There are copper, silver, and lead mines. Skirmishes occurred in Nogales against Pancho Villa in 1916. Industrial development, primarily between ...
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Alaska North Slope
Alaska North Slope or Arctic North Slope, region, N Alaska, sloping from the Brooks Range N to the Arctic Ocean. In 1968 large petroleum reserves were found in the Prudhoe Bay area. In 1977 the 800-mi (1,287 km) Trans-Alaska pipeline was completed to carry oil S to the port of Valdez, on the ...
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match
match small stick whose chemically coated tip bursts into flame when struck on a rough surface. Before the introduction of the match, fire was made by friction methods using the stick and the groove, the fire drill, or flint, tinder, and steel, or by employing a magnifying glass. Attempts in the 18...
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Black Panthers
Black Panthers U.S. African-American militant party, founded (1966) in Oakland, Calif., by Huey P. Newton and Bobby Seale. Originally espousing violent revolution as the only means of achieving black liberation, the Black Panthers called on African Americans to arm themselves for the liberation str...
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blindness
blindness partial or complete loss of sight. Blindness may be caused by injury, by lesions of the brain or optic nerve, by disease of the cornea or retina, by pathological changes originating in systemic disorders (e.g., diabetes ) and by cataract , glaucoma , or retinal detachment. Blindness ca...
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antidiuretic hormone
antidiuretic hormone , polypeptide hormone secreted by the posterior pituitary gland . Its principal action is to regulate the amount of water excreted by the kidneys. Antidiuretic hormone (ADH), known also as vasopressin, causes the kidneys to resorb water directly from the renal tubules, thus con...
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astringent
astringent , substance that shrinks body tissues. Astringent medicines cause shrinkage of mucous membranes or exposed tissues and are often used internally to check discharge of serum or mucous secretions in sore throat, hemorrhage, diarrhea, or peptic ulcer. Externally applied astringents, which ca...
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cold fusion
cold fusion or low-temperature fusion, nuclear fusion of deuterium, an isotope of hydrogen , at or relatively near room temperature. Fusion, the reaction involved in the release of the destructive energy of a hydrogen bomb , requires extremely high temperatures, and investigations of fusion a...
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permafrost
permafrost permanently frozen soil, subsoil, or other deposit, characteristic of arctic and some subarctic regions; similar conditions are also found at very high altitudes in mountain ranges. In 1962 measurements in a borehole drilled on Melville Island, Northwest Territories, Canada, showed that ...
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Rush-Bagot Convention
Rush-Bagot Convention , 1817, agreement between the United States and Great Britain concerning the Canadian border. It consisted of the exchange of notes signed by Richard Rush , Acting Secretary of State of the United States, and Charles Bagot, British minister in Washington. In 1818 the U.S. Sena...
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