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dog racing

(Encyclopedia)dog racing, trials of speed between dogs. Now contested on oval tracks, the sport developed from the ancient practice of coursing, in which specially trained dogs chase game animals in the open field....

cyclamate

(Encyclopedia)cyclamate sīˌkləmātˌ, –mət [key], any member of a group of salts of cyclamic acid (cyclohexanesulfamic acid). The sodium and calcium salts were commonly used as artificial sweeteners until 196...

Paré, Ambroise

(Encyclopedia)Paré, Ambroise äNbrwäzˈ pärāˈ [key], c.1510–1590, French surgeon. Serving in the army, he revived the use of ligature instead of cautery with boiling oil and continued to devise and champion ...

fertilizer

(Encyclopedia)fertilizer, organic or inorganic material containing one or more of the nutrients—mainly nitrogen, phosphorus, and potassium, and other essential elements required for plant growth. Added to the soi...

parthenogenesis

(Encyclopedia)parthenogenesis pärˌthənōjĕnˈəsĭs [key] [Gr.,=virgin birth], in biology, a form of reproduction in which the ovum develops into a new individual without fertilization. Natural parthenogenesis ...

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...

Van Allen radiation belts

(Encyclopedia)CE5 Van Allen radiation belts: The solar wind, a stream of protons, electrons, and ions coming from the sun, gives the belts their asymmetrical shape. Van Allen radiation belts, belts of radiation...

acetate

(Encyclopedia)acetate ăsˈĭtātˌ [key], one of the most important forms of artificial cellulose-based fibers; the ester of acetic acid. The first patents for the production of fibers from cellulose acetate appea...

expert system

(Encyclopedia)expert system, a computer system or program that uses artificial intelligence techniques to solve problems that ordinarily require a knowledgeable human. The method used to construct such systems, kno...

Pedersen, Charles John

(Encyclopedia)Pedersen, Charles John, 1904–89, American chemist, b. Busan, Korea, M.S. Massachusetts Institute of Technology, 1927. After finishing his studies, Pedersen began work as a research chemist for the D...