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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...

planetary science

(Encyclopedia)planetary science or planetology, study of planets and planetary systems as a whole. Planetary science applies the theories and methods of traditional disciplines such as astronomy, geology, physics, ...

zero

(Encyclopedia)zero, that number which, when added to any number, leaves the latter unchanged; its symbol is 0. The introduction of zero into the decimal system was the most significant achievement in the developmen...

Weizmann, Chaim

(Encyclopedia)Weizmann, Chaim khīmˈ vītsˈmän [key], 1874–1952, scientist and Zionist leader, first president (1948–52) of Israel, b. Russia, grad. Univ. of Freiburg, 1899. He lectured in chemistry at the U...

carbonated beverage

(Encyclopedia)carbonated beverage, an effervescent drink that releases carbon dioxide under conditions of normal atmospheric pressure. Carbonation may occur naturally in spring water that has absorbed carbon dioxid...

carbonyl group

(Encyclopedia)carbonyl group kärˈbənĭl [key], in chemistry, functional group that consists of an oxygen atom joined by a double bond to a carbon atom. The carbon atom is joined to the remainder of the molecule ...

biology

(Encyclopedia)biology, the science that deals with living things. It is broadly divided into zoology, the study of animal life, and botany, the study of plant life. Subdivisions of each of these sciences include cy...

fruit

(Encyclopedia)CE5 Types of fruit fruit, matured ovary of the pistil of a flower, containing the seed. After the egg nucleus, or ovum, has been fertilized (see fertilization) and the embryo plantlet begins to fo...

Jewish liturgical music

(Encyclopedia)Jewish liturgical music, the music used in the religious services of the Jews. The Bible and the Talmud record that spontaneous music making was common among the ancient Jews on all important occasion...

tennessine

(Encyclopedia)tennessine tĕnˈəsēn [key], artificially produced radioactive chemical element; symbol Ts; at. no. 117; mass number of most stable isotope 294; m.p., b.p., sp. gr., and valence unknown. Tennessine ...