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impedance

(Encyclopedia)impedance, in electricity, measure in ohms of the degree to which an electric circuit resists the flow of electric current when a voltage is impressed across its terminals. Impedance is expressed as t...

electroconvulsive therapy

(Encyclopedia)electroconvulsive therapy in psychiatry, treatment of mood disorders by means of electricity; the broader term “shock therapy” also includes the use of chemical agents. The therapeutic possibiliti...

Gregory of Narek, Saint

(Encyclopedia)Gregory of Narek, Saint, c.950–1003, Armenian monk, mystic poet, and theologian, Doctor of the Church. He entered monastic life at an early age, becoming a priest at age 25. Gregory wrote letters, o...

facsimile

(Encyclopedia)facsimile făksĭmˈəlē [key] or fax, in communications, system for transmitting pictures or other graphic matter by wire or radio. Facsimile is used to transmit such materials as documents, telegra...

Wernigerode

(Encyclopedia)Wernigerode vĕrnēgərōˈdə [key], city (1994 pop. 36,905), Saxony-Anhalt, central Germany, at the northern foot of the Harz Mts. It is an industrial city, a tourist center, and an important road a...

Kota

(Encyclopedia)Kota kōˈtə [key], city (1991 pop. 537,371), Rajasthan state, NW India, on the Chambal River. Kota, enclosed by a massive wall, is a district administrative center and a market for sugarcane, oilsee...

Gujranwalla

(Encyclopedia)Gujranwalla go͝ojˌränˈvälə [key], city, NE Pakistan. A road and rail hub, with linkage to Peshawar ...

Waterford, town, United States

(Encyclopedia)Waterford, town (1990 pop. 17,930), New London co., SE Conn., on Long Island Sound; settled c.1653, inc. as a separate town from New London, 1801. Mainly residential, it has a recording and film studi...

Macbeth

(Encyclopedia)Macbeth măkbĕthˈ [key], d. 1057, king of Scotland (1040–57). He succeeded his father as governor of the province of Moray c.1031 and was a military commander for Duncan I. In 1040 he killed Dunca...

opal

(Encyclopedia)opal ōˈpəl [key], a mineral consisting of poorly crystalline to amorphous silica, SiO2·nH2O; the water content is quite variable but usually ranges from 3% to 10%. Common opal is usually colorless...