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Niobrara

(Encyclopedia)Niobrara nīəbrârˈə [key], river, c.430 mi (690 km) long, rising in the High Plains, E Wyo., and flowing E across N Nebraska to the Missouri River on Nebraska's northeast border. The Mirage Flats ...

melamine

(Encyclopedia)melamine mĕlˈəmēnˌ [key], common name for 2,4,6-triamino-1,3,5-triazine. Melamine is a trimer (see polymer) of cyanamide, H2NC≡N, and is synthesized from calcium carbide. It condenses with form...

Moore, Barrington

(Encyclopedia)Moore, Barrington, 1913–2005, American sociologist and political scientist. Moore wrote a number of books on historical sociology that focus on Soviet society. Based at the Russian Research Center a...

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...

rare earths

(Encyclopedia)rare earths, in chemistry, oxides of the rare-earth metals. They were once thought to be elements themselves. They are widely distributed in the earth's crust and are fairly abundant, although they we...

thrombolytic drug

(Encyclopedia)thrombolytic drug thrŏmˌbəlĭtˈĭk [key] or clot-dissolving drug, substance, such as streptokinase or tissue plasminogen activator (tPA), that causes the breakdown of blood clots (see thrombosis) ...

saxophone

(Encyclopedia)saxophone, musical instrument invented in the 1840s by Adolphe Sax. Although it uses the single reed of the clarinet family, it has a conical tube and is made of metal. By 1846 there was a double fami...

Cleveland, Frederick Albert

(Encyclopedia)Cleveland, Frederick Albert, 1865–1946, American economist, b. Sterling, Ill., studied at DePauw Univ. and at the Univ. of Chicago, Ph.D. Univ. of Pennsylvania, 1900. He taught at the Univ. of Penns...

dative

(Encyclopedia)dative dāˈtĭv [key] [Lat.,=giving], in Latin grammar, the case typically used to refer to an indirect object, i.e., a secondary recipient of an action. For example, him in I gave him a book is tran...

radiology

(Encyclopedia)radiology, branch of medicine specializing in the use of X rays, gamma rays, radioactive isotopes, and other forms of radiation in the diagnosis and treatment of disease. X ray machines and fluoroscop...