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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 ...

Nestroy, Johann Nepomuk

(Encyclopedia)Nestroy, Johann Nepomuk yōˈhän nāˈpōmo͝ok nĕsˈtroi [key], 1802–62, Austrian dramatist and actor. A successful performer in comedies and operettas, he later proved himself a brilliant writer...

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...

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...

Casa, Giovanni della

(Encyclopedia)Casa, Giovanni della jōvänˈnē dĕlˈlä käˈzä [key], 1503–56, Italian cleric and poet. He was archbishop of Benevento and papal nuncio to Venice. He wrote lyric verse, a life of Bembo, and a ...

castor oil

(Encyclopedia)castor oil, yellowish oil obtained from the seed of the castor bean. The oil content of the seeds varies from about 20% to 50%. After the hulls are removed the seeds are cold-pressed. Medicinal castor...

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...

pellagra

(Encyclopedia)pellagra pəlăgˈrə [key], deficiency disease due to a lack of niacin (nicotinic acid), one of the components of the B complex vitamins in the diet. Niacin is plentiful in yeast, organ meats, peanut...