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Constellations (table)

(Encyclopedia)Constellations 1 Zodiac constellation. ...

stem cells

(Encyclopedia)stem cells, unspecialized human or animal cells that can produce mature specialized body cells and at the same time replicate themselves. Embryonic stem cells are derived from a blastocyst (the blastu...

vitamin

(Encyclopedia)vitamin, group of organic substances that are required in the diet of humans and animals for normal growth, maintenance of life, and normal reproduction. Vitamins act as catalysts; very often either t...

AIDS, in medicine

(Encyclopedia)AIDS or acquired immunodeficiency syndrome, fatal disease caused by a rapidly mutating retrovirus that attacks the immune system and leaves the victim vulnerable to infections, malignancies, and neuro...

Grant, Ulysses Simpson

(Encyclopedia)Grant, Ulysses Simpson, 1822–85, commander in chief of the Union army in the Civil War and 18th President (1869–77) of the United States, b. Point Pleasant, Ohio. He was originally named Hiram Uly...

censorship

(Encyclopedia)censorship, official prohibition or restriction of any type of expression believed to threaten the political, social, or moral order. It may be imposed by governmental authority, local or national, by...

marijuana

(Encyclopedia)marijuana or marihuana, drug obtained from the flowering tops, stems, and leaves of the hemp plant, Cannabis sativa (see hemp) or C. indica; the latter species can withstand colder climates. It is one...

psychology

(Encyclopedia)psychology, science or study of the thought processes and behavior of humans and other animals in their interaction with the environment. Psychologists study processes of sense perception, thinking, l...

Venezuela

(Encyclopedia)CE5 Venezuela vĕnəzwāˈlə, Span. vānāswāˈlä [key], officially the Bolivarian Republic of Venezuela, republic (2015 est. pop. 29,275,000), 352,143 sq mi (912,050 sq km), N South America. Ve...

Napoleon I

(Encyclopedia)CE5 Napoleonic Europe (1812) Napoleon I nəpōˈlēən, Fr. näpôlāōNˈ [key], 1769–1821, emperor of the French, b. Ajaccio, Corsica, known as “the Little Corporal.” The Napoleonic...