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Ashkin, Arthur

(Encyclopedia)Ashkin, Arthur, 1922–2020, American physicist, b. Brooklyn, N.Y., Ph.D. Cornell, 1952. Ashkin worked for four decades at Bell Laboratories, retiring in 1992. Ashkin researched microwaves, nonlinear ...

ACE inhibitor

(Encyclopedia)ACE inhibitor ănˌjēōtĕnˈsĭn [key], drug used to reduce elevated blood pressure (see hypertension), to treat congestive heart failure, and to alleviate strain on hea...

leishmaniasis

(Encyclopedia)leishmaniasis lēshˌmənīˈəsĭs [key], any of a group of tropical diseases caused by parasitic protozoans of the genus Leishmania. The parasites live in dogs, foxes, rodents, and humans; they are ...

toxemia

(Encyclopedia)toxemia tŏksēˈmēə [key], disease state caused by the presence in the blood of bacterial toxins or other harmful substances. The effects of the bacterial toxins known as endotoxins are relatively ...

Sarcodina

(Encyclopedia)Sarcodina, the largest phylum (11,500 living species and 33,000 fossil species) of protozoans). It comprises the amebas and related organisms; which are all solitary cells that move and capture food b...

Petrified Forest National Park

(Encyclopedia)Petrified Forest National Park, 93,533 acres (37,881 hectares), E Ariz.; est. as a national monument 1906, designated a national park 1962. A part of the Painted Desert, it contains the largest known ...

Cultural Revolution

(Encyclopedia)Cultural Revolution, 1966–76, mass mobilization of urban Chinese youth inaugurated by Mao Zedong in an attempt to prevent the development of a bureaucratized Soviet style of Communism. Mao closed sc...

Tyler, Wat

(Encyclopedia)Tyler, Wat, d. 1381, English rebel. His given name appears in full as Walter; his surname signifies the trade of a roof tiler. He came into prominence as the leader of the rebellion of 1381, known as ...

Stolypin, Piotr Arkadevich

(Encyclopedia)Stolypin, Piotr Arkadevich pyôˈtər ərkäˈdyĭvĭch stəlĭˈpĭn [key], 1862–1911, Russian premier and minister of the interior (1906–11) for Czar Nicholas II. He sought to fight the revoluti...

epilepsy

(Encyclopedia)epilepsy, a chronic disorder of cerebral function characterized by periodic convulsive seizures. There are many conditions that have epileptic seizures. Sudden discharge of excess electrical activity,...