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rhythm, biological

(Encyclopedia)rhythm, biological, or biorhythm, cyclic pattern of physiological changes or changes in activity in living organisms, most often synchronized with daily, monthly, or annual cyclical changes in the env...

Palacký, František

(Encyclopedia)Palacký, František fränˈtyĭshĕk päˈlätskē [key], 1798–1876, Czech nationalist and historian, b. Moravia. Regarded as the father of the modern Czech nation, Palacký played a leading role i...

nitric oxide

(Encyclopedia)nitric oxide or nitrogen monoxide, a colorless gas formed by the combustion of nitrogen and oxygen as given by the reaction: energy + N2 + O2 → 2NO; m.p. −163.6℃; b.p. −151.8℃. Nitric oxide ...

nonmetal

(Encyclopedia)nonmetal, chemical element possessing certain properties by which it is distinguished from a metal. In general, this distinction is drawn on the basis that a nonmetal tends to accept electrons and for...

sting

(Encyclopedia)sting, in zoology, organ found in bees, many wasps, some ants, and in scorpions and sting rays, used defensively as well as to kill or paralyze prey. In the bee and the wasp the venom is produced by g...

carbonated beverage

(Encyclopedia)carbonated beverage, an effervescent drink that releases carbon dioxide under conditions of normal atmospheric pressure. Carbonation may occur naturally in spring water that has absorbed carbon dioxid...

Black Hawk War

(Encyclopedia)Black Hawk War, conflict between the Sac and Fox and the United States in 1832. After the War of 1812, whites settling the Illinois country exerted pressure on the Native Americans. A treaty of 1804, ...

first aid

(Encyclopedia)first aid, immediate and temporary treatment of a victim of sudden illness or injury while awaiting the arrival of medical aid. Proper early measures may be instrumental in saving life and ensuring a ...

aspirin

(Encyclopedia)aspirin, acetyl derivative of salicylic acid (see salicylate) that is used to lower fever, relieve pain, reduce inflammation, and thin the blood. Common conditions treated with aspirin include headach...

Manipur

(Encyclopedia)Manipur mənĭpo͝orˈ [key], state (2001 provisional pop. 2,388,634), 8,628 sq mi (22,347 sq km), NE India, bordered by Myanmar on the south and east. Imphal is the capital. The terrain, mostly jungl...