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colon cancer

(Encyclopedia)colon cancer, cancer of any part of the colon (often called the large intestine). Colon cancer is the second most common cancer diagnosed in the United States. Epidemiological evidence has shown that ...

food adulteration

(Encyclopedia)food adulteration, act of intentionally debasing the quality of food offered for sale either by the admixture or substitution of inferior substances or by the removal of some valuable ingredient. The ...

aggression

(Encyclopedia)aggression, a form of behavior characterized by physical or verbal attack. It may appear either appropriate and self-protective, even constructive, as in healthy self-assertiveness, or inappropriate a...

sulfate

(Encyclopedia)sulfate, chemical compound containing the sulfate (SO4) radical. Sulfates are salts or esters of sulfuric acid, H2SO4, formed by replacing one or both of the hydrogens with a metal (e.g., sodium) or a...

Santayana, George

(Encyclopedia)Santayana, George säntäyäˈnä [key], 1863–1952, American philosopher and poet, b. Madrid, Spain. Santayana's philosophic stance has been given the apparently opposite descriptions of materiali...

goldwork

(Encyclopedia)goldwork, ornaments, jewelry, and vessels created from gold. Such works have figured in almost every stage of civilization as symbols of wealth and power. During the craft revival of the 1960s and 7...

weights and measures

(Encyclopedia)CE5 weights and measures, units and standards for expressing the amount of some quantity, such as length, capacity, or weight; the science of measurement standards and methods is known as metrology...

coral reefs

(Encyclopedia)coral reefs, limestone formations produced by living organisms, found in shallow, tropical marine waters. In most reefs, the predominant organisms are stony corals, colonial cnidarians that secrete an...

ethanol

(Encyclopedia)ethanol ĕthˈənōlˌ [key] or ethyl alcohol, CH3CH2OH, a colorless liquid with characteristic odor and taste; commonly called grain alcohol or simply alcohol. Ethanol is used extensively as a solv...

aphid

(Encyclopedia)aphid or plant louse, tiny, usually green, soft-bodied, pear-shaped insect injurious to vegetation. It is also called greenfly and blight. Aphids are mostly under 1⁄4 in. (6 mm) long. Some are wingl...