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incubator

(Encyclopedia)incubator, apparatus for the maintenance of controlled conditions in which eggs can be hatched artificially. Incubator houses with double walls of mud, a fireroom, and several compartments each holdin...

skywriting

(Encyclopedia)skywriting, advertising medium in which aircraft spell out trade names and sales slogans in the sky by means of the controlled emission of thick smoke. The technique was first developed (1922) by J. C...

perfluoroalkyl and polyfluoroalkyl substances

(Encyclopedia)perfluoroalkyl and polyfluoroalkyl substances (PFAS), a group of several thousand synthetic organic chemical compounds made up of a chain of carbon atoms bonded to fluorine atoms. PFAS, which resist w...

Webb Space Telescope

(Encyclopedia)Webb Space Telescope or James Webb Space Telescope (JWST), is an infrared space telescope, the largest in space at its launc...

cape buffalo

(Encyclopedia)cape buffalo, species of short-haired African ungulate, or hoofed mammal, Syncerus caffer. The cape, or African, buffalo may reach 7 ft (2.1 m) in length, weigh more than 1,500 lb (670 kg), and reach ...

Lenz's law

(Encyclopedia)Lenz's law, physical law, discovered by the German scientist H. F. E. Lenz in 1834, that states that the electromotive force (emf) induced in a conductor moving perpendicular to a magnetic field tends...

Lang, Fritz

(Encyclopedia)Lang, Fritz läng [key], 1890–1976, German-American film director, b. Vienna. His silent and early sound films, notably the iconic masterpiece Metropolis (1926) with its dystopian vision of the futu...

varicose vein

(Encyclopedia)varicose vein, superficial vessel that is abnormally lengthened, twisted, or dilated, seen most often on the legs and thighs. Varicose veins develop spontaneously, and are usually attributed to a here...

incinerator

(Encyclopedia)incinerator, furnace for burning refuse. The older and simpler kind of incinerator was a brick-lined cell with a metal grate over a lower ash pit, with one opening in the top or side for loading and a...

inflammation

(Encyclopedia)inflammation, reaction of the body to injury or to infectious, allergic, or chemical irritation. The symptoms are redness, swelling, heat, and pain resulting from dilation of the blood vessels in the ...