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genetic engineering

(Encyclopedia)CE5 Genetic engineering: Gene-splicing techniques genetic engineering, the use of various methods to manipulate the DNA (genetic material) of cells to change hereditary traits or produce biologica...

designer drug

(Encyclopedia)designer drug, chemical substance synthesized in a laboratory that is intended to have effects similar to those of a drug that is a controlled substance, such as methamphetamine, marijuana, LSD, or an...

United Mine Workers of America

(Encyclopedia)United Mine Workers of America (UMW), international labor union formed (1890) by the amalgamation of the National Progressive Union (organized 1888) and the mine locals under the Knights of Labor. It ...

poliomyelitis

(Encyclopedia)poliomyelitis pōˌlēōmīˌəlīˈtĭs [key], polio, or infantile paralysis, acute viral infection, mainly of children but also affecting older persons. Historically, there were three immunologic ty...

free silver

(Encyclopedia)free silver, in U.S. history, term designating the political movement for the unlimited coinage of silver. In 1896 free silver became the major issue of a presidential campaign when William Jennings...

herbal medicine

(Encyclopedia)herbal medicine, use of natural plant substances (botanicals) to treat and prevent illness. The practice has existed since prehistoric times and flourishes today as the primary form of medicine for pe...

Annan, Kofi Atta

(Encyclopedia)Annan, Kofi Atta kōˈfē äˈtä ănˈən [key] 1938–2018, Ghanaian diplomat, the seventh secretary-general of the United Nations (1997–2006) and the first person to hold that office who came fro...

sunspots

(Encyclopedia)sunspots, dark, usually irregularly shaped spots on the sun's surface that are actually solar magnetic storms. The spots are darker because the temperature of the spots is lower than that of the surro...

pesticide

(Encyclopedia)pesticide, biological, physical, or chemical agent used to kill plants or animals that are harmful to people; in practice, the term pesticide is often applied only to chemical agents. Various pesticid...

photographic processing

(Encyclopedia)photographic processing, set of procedures by which the latent, or invisible, image produced when a photographic film is exposed to light is made into a permanent visible image. The negative may b...