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transducer

(Encyclopedia)transducer, device that accepts an input of energy in one form and produces an output of energy in some other form, with a known, fixed relationship between the input and output. One widely used class...

Rose, Irwin

(Encyclopedia)Rose, Irwin, 1926–2015, American biochemist, b. Brooklyn, N.Y., Ph.D. Univ. of Chicago, 1952. Rose was on the faculty of Yale Medical School from 1954 to 1963 and a senior member of the Fox Chase Ca...

Almoravids

(Encyclopedia)Almoravids ălmôrˈəvĭdz [key], Berber Muslim dynasty that ruled Morocco and Muslim Spain in the 11th and 12th cent. The Almoravids may have originated in what is now Mauritania. The real founder w...

gnat

(Encyclopedia)gnat, common name for any one of a number of small, fragile-looking two-winged flies of the suborder Nematocera, order Diptera, which includes the families Tipulidae (crane flies), Bibionidae (hairfli...

Missouri River basin project

(Encyclopedia)Missouri River basin project, comprehensive plan authorized in 1944 for the coordinated development of water resources of the Missouri River and its tributaries, draining an area of c.513,300 sq mi (1...

Tula , ancient city, Mexico

(Encyclopedia)Tula to͞oˈlä [key], ancient city in the present state of Hidalgo, central Mexico. It was one of the chief urban centers of the Toltec. The city is believed to be Tollán, the legendary Toltec capit...

White Nile

(Encyclopedia)White Nile, river, one of the chief tributaries of the Nile, E Africa. The name is sometimes used for the 600 mi (970 km) long section of the river known as the Bahr el Abiad that extends upstream fro...

multiple birth

(Encyclopedia)multiple birth, bringing forth of more than one offspring at birth. Although many smaller mammals bear several young at a time, multiple births are relatively uncommon in humans and other primates. Tw...

reproductive system

(Encyclopedia)CE5 Reproductive system reproductive system, in animals, the anatomical organs concerned with production of offspring. In humans and other mammals the female reproductive system produces the femal...

electrochemistry

(Encyclopedia)electrochemistry, science dealing with the relationship between electricity and chemical changes. Of principal interest are the reactions that take place between electrodes and the electrolytes in ele...