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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 ...

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...

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...

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...

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...

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...

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...

Job

(Encyclopedia)Job jōb [key], book of the Bible. The book is of unknown authorship and date, although many scholars assign it to a time between 600 b.c. and 400 b.c. A lament in narrative form, the subject is the p...