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dialysis

(Encyclopedia)dialysis dīălˈĭsĭs [key], in chemistry, transfer of solute (dissolved solids) across a semipermeable membrane. Strictly speaking, dialysis refers only to the transfer of the solute; transfer of t...

communications satellite

(Encyclopedia)communications satellite artificial satellite that functions as part of a global radio-communications network. Echo 1, the first communications satellite, launched in 1960, was an instrumented inflat...

Colombo

(Encyclopedia)Colombo kəlŭmˈbō [key], largest city (2021 est. metro area pop. 619,000) and former capi...

garden

(Encyclopedia)garden, land set aside for the cultivation of flowers, herbs, vegetables, or small fruits, for either utility or ornament. Gardens range in size from window boxes and small dooryard plots to the publi...

space medicine

(Encyclopedia)space medicine, study of the medical and biological effects of space travel on living organisms. The principal aim is to discover how well and for how long humans can withstand the extreme conditions ...

irrigation

(Encyclopedia)irrigation, in agriculture, artificial watering of the land. Although used chiefly in regions with annual rainfall of less than 20 in. (51 cm), it is also used in wetter areas to grow certain crops, e...

neural network

(Encyclopedia)neural network or neural computing, computer architecture modeled upon the human brain's interconnected system of neurons. Neural networks imitate the brain's ability to sort out patterns and learn fr...

naturalism, in literature

(Encyclopedia)naturalism, in literature, an approach that proceeds from an analysis of reality in terms of natural forces, e.g., heredity, environment, physical drives. The chief literary theorist on naturalism was...

oyster

(Encyclopedia)oyster, bivalve mollusk found in beds in shallow, warm waters of all oceans. The shell is made up of two valves, the upper one flat and the lower convex, with variable outlines and a rough outer surfa...

poison

(Encyclopedia)poison, any agent that may produce chemically an injurious or deadly effect when introduced into the body in sufficient quantity. Some poisons can be deadly in minute quantities, others only if relati...