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Best, Charles Herbert

(Encyclopedia)Best, Charles Herbert, 1899–1978, Canadian physiologist, b. West Pembroke, Maine. With F. G. Banting and J. R. R. Macleod he discovered (1921) the use of insulin in the treatment of diabetes. He was...

Westermarck, Edward Alexander

(Encyclopedia)Westermarck, Edward Alexander vĕsˈtərmärk, wĕsˈ– [key], 1862–1939, Finnish social philosopher and anthropologist. He was professor of sociology at the Univ. of London (1907–30) and profess...

language acquisition

(Encyclopedia)language acquisition, the process of learning a native or a second language. The acquisition of native languages is studied primarily by developmental psychologists and psycholinguists. Although how c...

heart, artificial

(Encyclopedia)heart, artificial, external or surgically implanted mechanical device designed to replace a patient's diseased heart. The first one used on a human being, the Jarvik-7, was implanted (1982) in Barney ...

Holocene epoch

(Encyclopedia)Holocene epoch hŏlˈəsēn [key] or Recent epoch, most recent of all subdivisions of geologic time, ranging from the present back to the time (c.11,000 years ago) of almost complete withdrawal of the...

hygrometer

(Encyclopedia)hygrometer hīgrŏmˈətər [key], instrument used to measure the moisture content of a gas, as in determining the relative humidity of air. The temperature at which dew or frost forms is a measure of...

coronavirus

(Encyclopedia)coronavirus, any of a group (family Coronaviridae, subfamily Orthocoronavirinae) of enveloped single-stranded RNA viruses that have a crownlike or sunlike appearance under an electron microscope due t...

rock carvings and paintings

(Encyclopedia)rock carvings and paintings, designs inscribed on rock surfaces and huge stone monuments in many parts of the world by prehistoric or preindustrial peoples. They have been found on every continent and...

automation

(Encyclopedia)automation, automatic operation and control of machinery or processes by devices, such as robots that can make and execute decisions without human intervention. The principal feature of such devices i...

aging

(Encyclopedia)aging, in biology, cumulative changes in an organism, organ, tissue, or cell leading to a decrease in functional capacity. In humans, aging is associated with degenerative changes in the skin, bones, ...