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parathyroid hormone

(Encyclopedia)parathyroid hormone or parathormone, a hormone secreted by the parathyroid glands that regulates the metabolism of calcium and phosphate in the body. It has been purified extensively and appears to be...

adolescence

(Encyclopedia)adolescence, time of life from onset of puberty to full adulthood. The exact period of adolescence, which varies from person to person, falls approximately between the ages 12 and 20 and encompasses b...

bioethics

(Encyclopedia)bioethics, in philosophy, a branch of ethics concerned with issues surrounding health care and the biological sciences. These issues include the morality of abortion, euthanasia, in vitro fertilizatio...

nerve gas

(Encyclopedia)nerve gas, any of several poison gases intended for military use, e.g., tabun, sarin, soman, and VX. Nerve gases were first developed by Germany during World War II but were not used at that time. The...

Middle East

(Encyclopedia)Middle East, term traditionally applied by western Europeans to the countries of SW Asia and NE Africa lying W of Afghanistan, Pakistan, and India. Thus defined it includes Cyprus, the Asian part of T...

Munk, Walter Heinrich

(Encyclopedia)Munk, Walter Heinrich, 1917–2019, American oceanographer and geophysicist, b. Vienna (then in Austria-Hungary), B.S. California Institute of Technology, 1939, Ph.D Univ. of California, Los Angeles, ...

Mahan, Alfred Thayer

(Encyclopedia)Mahan, Alfred Thayer məhănˈ [key], 1840–1914, U.S. naval officer and historian, b. West Point, N.Y. A Union naval officer in the Civil War, he later lectured on naval history and strategy at the ...

Marion, Francis

(Encyclopedia)Marion, Francis mârˈēən [key], c.1732–1795, American Revolutionary soldier, known as the Swamp Fox, b. near Georgetown, S.C. He was a planter and Indian fighter before joining (1775) William Mou...

Eudes

(Encyclopedia)Eudes ōˈdō [key], c.860–898, count of Paris, French king (888–898). The son of Robert the Strong, he was an antecedent of the Capetian royal house in France. He defended Paris against the Norse...

Valens

(Encyclopedia)Valens väˈlənz [key], c.328–378, Roman emperor of the East (364–78). Brother and coregent of Valentinian I, Valens followed in most respects his brother's policies but, unlike him, embraced Ari...