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mutation

(Encyclopedia)mutation, in biology, a sudden, random change in a gene, or unit of hereditary material, that can alter an inheritable characteristic. Most mutations are not beneficial, since any change in the delica...

induction, in electricity and magnetism

(Encyclopedia)induction, in electricity and magnetism, common name for three distinct phenomena. Electromagnetic induction is the production of an electromotive force (emf) in a conductor as a result of a changing ...

James, William

(Encyclopedia)James, William, 1842–1910, American philosopher, b. New York City, M.D. Harvard, 1869; son of the Swedenborgian theologian Henry James and brother of the novelist Henry James. In 1872 he joined the ...

magic, in religion and superstition

(Encyclopedia)magic, in religion and superstition, the practice of manipulating and controlling the course of nature by preternatural means. Magic is based upon the belief that the universe is populated by unseen f...

ultraviolet radiation

(Encyclopedia)ultraviolet radiation, invisible electromagnetic radiation between visible violet light and X rays; it ranges in wavelength from about 400 to 4 nanometers and in frequency from about 1015 to 1017 hert...

dielectric

(Encyclopedia)dielectric dīˌĭlĕkˈtrĭk [key], material that does not conduct electricity readily, i.e., an insulator (see insulation). A good dielectric should also have other properties: It must resist breakd...

Compton effect

(Encyclopedia)Compton effect [for A. H. Compton], increase in the wavelengths of X rays and gamma rays when they collide with and are scattered from loosely bound electrons in matter. This effect provides strong ve...

conjunctivitis

(Encyclopedia)conjunctivitis kənjəngtəvīˈtəs [key], inflammation or infection of the mucosal membrane that covers the eyeball and lines the eyelid, usually acute, caused by a virus or, less often, by a bacill...

Chatterjee, Bankim Chandra

(Encyclopedia)Chatterjee, Bankim Chandra bəngˈkĭm chŭnˈdrə chäˈtərjē [key], 1838–94, Indian nationalist writer, b. Bengal. He popularized a Bengali prose style that became the vehicle of the major natio...

Chrysophyta

(Encyclopedia)Chrysophyta krəsŏfˈətə [key], phylum (division) of unicellular marine or freshwater organisms of the kingdom Protista consisting of the diatoms (class Bacillariophyceae), the golden, or golden-br...