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immunology

(Encyclopedia)immunology, branch of medicine that studies the response of organisms to foreign substances, e.g., viruses, bacteria, and bacterial toxins (see immunity). Immunologists study the tissues and organs of...

chemical equilibrium

(Encyclopedia)chemical equilibrium, state of balance in which two opposing reversible chemical reactions proceed at constant equal rates with no net change in the system. For example, when hydrogen gas, H2, and iod...

mass transit

(Encyclopedia)mass transit, public transportation systems designed to move large numbers of passengers. The history of mass transportation is intimately connected to industrialization, urbanization, and the sepa...

lintel

(Encyclopedia)lintel, in architecture, the horizontal member that spans an opening, such as a door or window, or that connects two columns. The post-and-lintel, or trabeated, system of construction, with spans limi...

Cincinnati, University of

(Encyclopedia)Cincinnati, University of, at Cincinnati; coeducational; founded 1819 as Cincinnati College, incorporated 1870 as a municipal university, opened 1873, affiliated with the state university system 1968....

Fabricius, Johan Christian

(Encyclopedia)Fabricius, Johan Christian yōhănˈ krĭsˈtyän fäbrēˈsyo͝os [key], 1745–1808, Danish entomologist. Influenced by the methods of Linnaeus, under whom he studied, he devised a system of classif...

Oregon, University of

(Encyclopedia)Oregon, University of, mainly at Eugene; state supported; coeducational; chartered 1872, opened 1876. Its is one of seven institutions in the Oregon Univ. System. The university has schools and colleg...

azimuth

(Encyclopedia)azimuth ăzˈəməth [key], in astronomy, one coordinate in the altazimuth coordinate system. It is the angular distance of a body measured westward along the celestial horizon from the observer's sou...

amobarbital

(Encyclopedia)amobarbital ămˌōbärˈbĭtäl [key], drug that acts as a nervous system depressant. See barbiturate. ...

Ganymede, in astronomy

(Encyclopedia)Ganymede gănˈēmēdˌ [key], in astronomy, one of the moons, or natural satellites, of Jupiter; the largest natural satellite in the solar system, it is larger than the planet Mercury. ...