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Cohen, Samuel Theodore

(Encyclopedia)Cohen, Samuel Theodore, 1921–2010, American physicist known as the “father of the neutron bomb,” b. Brooklyn, N.Y., grad. Univ. of California, Los Angeles, 1943. He worked on the Manhattan Proje...

pacemaker, artificial

(Encyclopedia)pacemaker, artificial, device used to stimulate a rhythmic heartbeat by means of electrical impulses. Implanted in the body when the heart's own electrical conduction system (natural pacemaker) does n...

Jansky, Karl Guthe

(Encyclopedia)Jansky, Karl Guthe, 1905–50, American radio engineer; b. Norman, Okla. After graduating (1927) from the Univ. of Wisconson, he joined the Bell Telephone Laboratories. While trying to determine the c...

CAT scan

(Encyclopedia)CAT scan kăt [key] [computerized axial tomography], X-ray technique that allows relatively safe, painless, and rapid diagnosis in previously inaccessible areas of the body; also called CT scan. An X-...

Luria, Salvador Edward

(Encyclopedia)Luria, Salvador Edward, 1912–1991, American physician, b. Turin, Italy, M.D., Univ. of Turin, 1935. He conducted research and taught at the Institute of Radium in Paris (1938–40), Columbia (1940�...

Muller, Hermann Joseph

(Encyclopedia)Muller, Hermann Joseph mŭlˈər [key], 1890–1967, American geneticist and educator, b. New York City, grad. Columbia (B.A., 1910; Ph.D., 1916). A student of Thomas Hunt Morgan, he taught (1915–18...

magnetic resonance imaging

(Encyclopedia)magnetic resonance imaging (MRI), noninvasive diagnostic technique that uses nuclear magnetic resonance to produce cross-sectional images of organs and other internal body structures. The patient lies...

second

(Encyclopedia)second, abbr. sec or s, fundamental unit of time in all systems of measurement. In practical terms, the second is 1/60 of a minute, 1/3,600 of an hour, or 1/86,400 of a day. Since the length of the da...

polycythemia

(Encyclopedia)polycythemia pŏlˌēsīthēˈmēə [key], condition characterized by an increase in the production of red blood cells, or erythrocytes, in the blood. Primary polycythemia, also called erythremia, or ...

psoriasis

(Encyclopedia)psoriasis sôrīˈəsĭs [key], occasionally acute but usually chronic and recurrent inflammation of the skin. The exact cause is unknown, but the disease appears to be an inherited, possibly autoimmu...