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fatigue, in physiology

(Encyclopedia)fatigue, in physiology, inability to perform reasonable and necessary physical or mental activity. Muscle fatigue, for example, results when the contractile properties of muscle are reduced, and conti...

endocarditis

(Encyclopedia)endocarditis ĕnˌdōkärdīˈtĭs [key], bacterial or fungal infection of the endocardium (inner lining of the heart) that can be either acute or subacute. In the acute form the symptoms (fever, mala...

pole, in electricity and magnetism

(Encyclopedia)pole, in electricity and magnetism, point where electric or magnetic force appears to be concentrated. A single electric charge located at a point is sometimes referred to as an electric monopole. An ...

quelea

(Encyclopedia)quelea kwēˈlēə [key], common name for an East African weaverbird, Quelea quelea. Less than 5 in. (13 cm) long and weighing slightly more than 1⁄2 oz (1.4 grams), these tiny birds are found throu...

pardon

(Encyclopedia)pardon, in law, exemption from punishment for a criminal conviction granted by the grace of the executive of a government. A general pardon to a class of persons guilty of the same offense (e.g., insu...

Parkinson's disease

(Encyclopedia)Parkinson's disease or Parkinsonism, degenerative brain disorder first described by the English surgeon James Parkinson in 1817. When there is no known cause, the disease usually appears after age 40 ...

franchise

(Encyclopedia)franchise, in government, a right specifically conferred on a group or individual by a government, especially the privilege conferred by a municipality on a corporation of operating public utilities, ...

incest

(Encyclopedia)incest, sexual relations between persons to whom marriage is prohibited by custom or law because of their close kinship. Ideas of kinship, however, vary widely from group to group, hence the definitio...

ivory-billed woodpecker

(Encyclopedia)ivory-billed woodpecker, common name for the largest of the North American woodpeckers, Campephilus principalis. Once plentiful in Southern hardwood forests, it was believed to be extinct or nearing e...

dynamics

(Encyclopedia)dynamics, branch of mechanics that deals with the motion of objects; it may be further divided into kinematics, the study of motion without regard to the forces producing it, and kinetics, the study o...