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malaria

(Encyclopedia)malaria, infectious parasitic disease that can be either acute or chronic and is frequently recurrent. Malaria is common in Africa, Central and South America, the Mediterranean countries, Asia, and ma...

sewage treatment

(Encyclopedia)sewage treatment: see septic tank; sewerage. ...

control surface

(Encyclopedia)control surface: see airfoil.

control systems

(Encyclopedia)control systems, combinations of components (electrical, mechanical, thermal, or hydraulic) that act together to maintain actual system performance close to a desired set of performance specifications...

gun control

(Encyclopedia)gun control, government limitation of the purchase and ownership of firearms. The availability of guns is controlled by nations and localities throughout the world. In the United States the “right o...

numerical control

(Encyclopedia)numerical control: see computer-aided manufacturing. ...

birth control

(Encyclopedia)birth control, practice of contraception for the purpose of limiting reproduction. Although contraceptive techniques had been known in ancient Egypt, Greece, and Rome, the modern movement for birth ...

rent control

(Encyclopedia)rent control, in economics and law, government regulation of rent to prevent unreasonable or excessive increases. In the United States, the federal government imposed rent control (and other price con...

Tu Youyou

(Encyclopedia)Tu Youyou, 1930–, Chinese pharmaceutical chemist, B.S. Peking Univ. School of Medicine, 1955. Tu has spent her entire career as a researcher at the China Academy of Traditional Chinese Medicine in B...

Centers for Disease Control and Prevention

(Encyclopedia)Centers for Disease Control and Prevention (CDC), agency of the U.S. Public Health Service since 1973, with headquarters in Atlanta; it was established in 1946 as the Communicable Disease Center. The ...