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sediment

(Encyclopedia)sediment, mineral or organic particles that are deposited by the action of wind, water, or glacial ice. These sediments can eventually form sedimentary rocks (see rock). Sediments form sedimentary ...

tungsten

(Encyclopedia)tungsten tŭngˈstən [key] [Swed.,=heavy stone], metallic chemical element; symbol W; at. no. 74; at. wt. 183.84; m.p. about 3,410℃; b.p. 5,660℃; sp. gr. 19.3 at 20℃; valence +2, +3, +4, +5, or...

atomic weight

(Encyclopedia)atomic weight, mean (weighted average) of the masses of all the naturally occurring isotopes of a chemical element, as contrasted with atomic mass, which is the mass of any individual isotope. Althoug...

paper

(Encyclopedia)paper, thin, flat sheet or tissue made usually from plant fiber but also from rags and other fibrous materials. It is used principally for printing and writing on but has many other applications. The ...

Mullis, Kary Banks

(Encyclopedia)Mullis, Kary Banks, 1944–2019, American biochemist, b. Lenoir, N.C., Ph.D. Univ. of California, Berkeley, 1972. Mullis was a researcher with Cetus Corp., Emeryville, Calif., from 1979 to 1986 and wi...

myosin

(Encyclopedia)myosin mīˈəsĭn [key], one of the two major protein constituents responsible for contraction of muscle. In muscle cells myosin is arranged in long filaments called thick filaments that lie parallel...

river blindness

(Encyclopedia)river blindness or onchocerciasis, disease caused by the parasitic nematode worm Onchocerca volvulus. The worm larvae are transmitted by the bites of blackflies (genus Simulium) that live in fast movi...

Defense Advanced Research Projects Agency

(Encyclopedia)Defense Advanced Research Projects Agency (DARPA), U.S. government agency administered by the Department of Defense (see Defense, United States Department of). It was established in 1958, in reaction ...

Gardiner, Stephen

(Encyclopedia)Gardiner, Stephen, 1493?–1555, English prelate. He was educated at Cambridge. He became secretary to Thomas (later Cardinal) Wolsey and later secured the favor of Henry VIII by a mission to Rome to ...

Holt, Joseph

(Encyclopedia)Holt, Joseph, 1807–94, American public official, judge advocate general of the U.S. army (1862–75), b. Breckinridge co., Ky. He became a widely known lawyer and political speaker in the old Southw...