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embryo screening

(Encyclopedia)embryo screening, procedure (see genetic testing) in which a single cell is removed from an embryo two or three days after it has been conceived through in vitro fertilization and tested for genetic a...

Morrison, Toni

(Encyclopedia)Morrison, Toni, 1931–2019, American writer, b. Lorain, Ohio, as Chloe Ardelia (later Anthony) Wofford; B.A. Howard Univ., 1953, M.F.A. Cornell, 1955. Her fiction is noted for its poetic language, lu...

Ngugi wa Thiong'o

(Encyclopedia)Ngugi wa Thiong'o ĕngo͞oˈgē wä tē-ŏngˈgō [key] or James Ngugi, 1938–, Kenyan writer, acclaimed as East Africa's foremost novelist. He studied at universities in Uganda and England. His firs...

Lessing, Doris

(Encyclopedia)Lessing, Doris, 1919–2013, British novelist, b. Kermanshah, Persia (now Iran) as Doris May Tayler. Largely self-educated, she was brought up on a farm in Southern Rhodesia (now Zimbabwe), and in 194...

labor, in economics

(Encyclopedia)labor, term used both for the effort of performing a task and for the workers engaged in the activity. In ancient times much of the work was done by slaves (see slavery). In the feudal period agricult...

Rogers, Robert

(Encyclopedia)Rogers, Robert, 1731–95, American frontiersman, b. Methuen, Mass. As a child he moved with his family to the New Hampshire frontier. In King George's War (1744–48) he served briefly as a scout. In...

Straus

(Encyclopedia)Straus strous [key], family of American merchants, public officials, and philanthropists. Isidor Straus, 1845–1912, b. Rhenish Bavaria, emigrated (1854) with his brothers to the United States in ord...

ordeal

(Encyclopedia)ordeal, ancient legal custom whereby an accused person was required to perform a test, the outcome of which decided the person's guilt or innocence. By an ordeal, appeal was made to divine authority t...

abortion

(Encyclopedia)abortion, expulsion of the products of conception before the embryo or fetus is viable. Any interruption of human pregnancy prior to the 28th week is known as abortion. The term spontaneous abortion, ...

alchemy

(Encyclopedia)alchemy ălˈkəmē [key], ancient art of obscure origin that sought to transform base metals (e.g., lead) into silver and gold; forerunner of the science of chemistry. Some scholars hold that it was ...