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shock

(Encyclopedia)shock, any condition in which the circulatory system is unable to provide adequate circulation to the body tissues, also called circulatory failure or circulatory collapse. Shock results in the slowin...

antique collecting

(Encyclopedia)antique collecting, the assembling of items of aesthetic, historical, and often monetary value from earlier eras. The term antique initially referred only to the preclassical and classical cultures of...

radioactivity

(Encyclopedia)CE5 Effects of a magnetic field on the products of radioactivity CE5 Disintegration series: Radioactive decay of radium-226 into lead-206 radioactivity, spontaneous disintegration or decay of t...

frostbite

(Encyclopedia)frostbite (chilblains), injury to the tissue caused by exposure to cold, usually affecting the extremities of the body, such as the hands, feet, ears, or nose. Extreme cold causes the small blood vess...

cyclosis

(Encyclopedia)cyclosis sīklōˈsĭs [key], streaming of cytoplasm within a living cell without deformation of the external cell membrane. In some plant cells there is a rapid rotatory cytoplasmic movement, which i...

biopsy

(Encyclopedia)biopsy bīäpˈsē [key], examination of cells or tissues removed from a living organism. Excised material may be studied in order to diagnose disease or to confirm findings of normality. Preparatory ...

Lorenzetti

(Encyclopedia)Lorenzetti lōrān-tsĕtˈtē [key], two brothers who were major Sienese painters. Pietro Lorenzetti, c.1280–c.1348, was first influenced by Duccio di Buoninsegna and Giovanni Pisano. His earliest k...

hall

(Encyclopedia)hall, a communicating passageway or, in medieval buildings, the large main room. In the feudal castle of N Europe it was a single apartment, and in it lord and retainers lounged, ate, and slept. From ...

Gregory XI

(Encyclopedia)Gregory XI, 1330–78, pope (1370–78), a Frenchman named Pierre Roger de Beaufort. He was the successor of Urban V, who had made an unsuccessful attempt to remove the papacy from Avignon to Rome (13...

graffito

(Encyclopedia)graffito gräf-fēˈtō [key]. 1 Method of ornamenting architectural plaster surfaces. The designs are produced by scratching a topcoat of plaster to reveal an undercoat of contrasting and deeper colo...