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electrocardiography

(Encyclopedia)electrocardiography ĭlĕkˌtrōkärdēŏgˈrəfē [key], science of recording and interpreting the electrical activity that precedes and is a measure of the action of heart muscles. Since 1887, when ...

uric acid

(Encyclopedia)uric acid yo͝orˈĭk [key], white, odorless, tasteless crystalline substance formed as a result of purine degradation in man, other primates, dalmatians, birds, snakes, and lizards. The last three gr...

Thomas, Norman Mattoon

(Encyclopedia)Thomas, Norman Mattoon, 1884–1968, American socialist leader, b. Marion, Ohio; grad. Princeton (1905), Union Theological Seminary (1911). He served as pastor of several Presbyterian churches and did...

gonadotropic hormone

(Encyclopedia)gonadotropic hormone gōˌnădətrŏpˈĭk [key] or gonadotropin, any one of three glycoprotein (see protein) hormones released by either the anterior pituitary gland or the placenta (the organ in whi...

flame

(Encyclopedia)flame, phenomenon associated with the chemical reaction of a gas that has been heated above its kindling temperature with some other gas, usually atmospheric oxygen (see combustion). The heat and ligh...

O'Connell, Daniel

(Encyclopedia)O'Connell, Daniel, 1775–1847, Irish political leader. He is known as the Liberator. Admitted to the Irish bar in 1798, O'Connell built up a lucrative law practice. Gradually he became involved in th...

barium

(Encyclopedia)barium bârˈēəm [key] [Gr.,=heavy], metallic chemical element; symbol Ba; at. no. 56; at. wt. 137.327; m.p. 725℃; b.p. 1,640℃; sp. gr. 3.5 at 20℃; valence +2. Barium is a soft, silver-white, ...

perturbation

(Encyclopedia)perturbation pŭrˌtərbāˈshən [key], in astronomy and physics, small force or other influence that modifies the otherwise simple motion of some object. The term is also used for the effect produce...

jet propulsion

(Encyclopedia)CE5 Types of jet engines: In the propeller-driven turbine a stream of high-velocity gases provides the power to drive the turbine and turn the propeller. In the jet-driven turbine the stream of gas...

draft riots

(Encyclopedia)draft riots, in the American Civil War, mob action to protest unfair Union conscription. The Union Conscription Act of Mar. 3, 1863, provided that all able-bodied males between the ages of 20 and 45 w...