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# transformation

/trans'feuhr may"sheuhn/, n.
1. the act or process of transforming.
2. the state of being transformed.
3. change in form, appearance, nature, or character.
4. Theat. a seemingly miraculous change in the appearance of scenery or actors in view of the audience.
5. Logic. Also called transform. one of a set of algebraic formulas used to express the relations between elements, sets, etc., that form parts of a given system.
6. Math.
a. the act, process, or result of transforming or mapping.
b. function (def. 4a).
7. Ling.
b. the process by which deep structures are converted into surface structures using transformational rules.
8. Genetics. the transfer of genetic material from one cell to another resulting in a genetic change in the recipient cell.
9. a wig or hairpiece for a woman.
[1400-50; late ME < LL transformation- (s. of transformatio) change of shape. See TRANS-, FORMATION]

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In mathematics, a rule for changing a geometric figure or algebraic expression into another, usually accompanied by a rule for transforming it back.

In geometry and topology, a transformation (e.g., flipping horizontally or vertically, rotating, or stretching vertically or horizontally) moves each point in a figure or graph to another position. A graph also undergoes a transformation when its coordinate system is changed. For example, the equations that establish a correspondence between the rectangular and polar coordinate systems constitute a transformation. In analysis, a transformation is a procedure that changes one function into another. Of special interest in many fields of mathematics are transformations forming a group, in which any two transformations applied successively produce the same result as another transformation in the group and each transformation has an inverse transformation (which undoes it) in the group. See also group theory, integral transform, linear transformation.

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in biology, one of several processes by which genetic material in the form of “naked” deoxyribonucleic acid ( DNA) is transferred between microbial cells. Its discovery and elucidation constitutes one of the significant cornerstones of molecular genetics. The term also refers to the change in an animal cell invaded by a tumour-inducing virus.

The study of transformation dates to the late 1920s, when an English physician, F. Griffith, discovered that pneumococcal cells (Streptococcus pneumoniae (pneumococcus)) could convert from a harmless form to a disease-causing type. He noticed that pneumococci may or may not have a capsular covering. Those cells with a capsule (forming smooth colonies) caused disease in mice; those lacking a capsule (and forming rough-surfaced colonies) were harmless. A mixture of living, nonencapsulated cells and heat-killed, capsulated cells, when inoculated into mice, caused disease. Living, encapsulated cells (pathogenic) were created by a “transforming principle” liberated from the dead cells to the living cells. The transformation was heritable. In 1943 a group of investigators at the Rockefeller Institute, New York City, identified that “transforming principle” as DNA.

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Universalium. 2010.

Synonyms:

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• transformation — [ trɑ̃sfɔrmasjɔ̃ ] n. f. • 1375; lat. transformatio 1 ♦ Action de transformer, opération par laquelle on transforme. ⇒ conversion. La transformation des matières premières. Industrie de transformation. « un de ces théoriciens qui ont rêvé [...]… …   Encyclopédie Universelle

• Transformation — (root transform ) may refer to:Transformation is also referred to as a turn.In science: * Transformation (geometry), in mathematics, as a general term applies to mathematical functions. ** Data transformation (statistics) in statistics. *… …   Wikipedia

• transformation — is the process by which transactions that are open at, or after, the record date/election transfer date are cancelled and/or replaced by new transactions in accordance with the terms of the reorganisation. Euroclear Clearing and Settlement… …   Financial and business terms

• Transformation — (lateinisch die Umformung) bezeichnet allgemein die Veränderung der Gestalt, Form oder Struktur. Der Begriff wird in einer Vielzahl von Themengebieten verwendet: Konvertierung (Informatik) in der Informatik die Überführung von Daten in ein… …   Deutsch Wikipedia

• transformation — Transformation. s. f. v. Changement d une forme en une autre. La transformation des metaux. la transformation fabuleuse de Protée. les Poëtes Grecs sont pleins de transformations fabuleuses …   Dictionnaire de l'Académie française

• Transformation — Trans for*ma tion, n. [L. transformatio: cf. transformation.] The act of transforming, or the state of being transformed; change of form or condition. Specifically: [1913 Webster] (a) (Biol.) Any change in an organism which alters its general… …   The Collaborative International Dictionary of English

• transformation — (n.) c.1400, from O.Fr. transformation and directly from L. transformationem (nom. transformatio), noun of action from pp. stem of transformare (see TRANSFORM (Cf. transform)) …   Etymology dictionary

• transformation — transformation. См. трансформация. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

• Transformation — (lat., »Umgestaltung«), in der Mathematik zunächst soviel wie Substitution (s. d.), dann aber auch jedes Verfahren, durch das aus gegebenen Figuren neue Figuren von andrer Lage und andrer Gestalt abgeleitet werden. Eine T. in diesem Sinn erhält… …   Meyers Großes Konversations-Lexikon

• Transformation — Transformation, gewöhnlich so viel wie Substitution (s.d.). Zwischen Scharen von Transformationen und von Substitutionen besteht jedoch der Unterschied, daß bei ersteren die Parameter stetig veränderliche Größen sind, während sie bei letzteren… …   Lexikon der gesamten Technik

• Transformation — (lat.), Umbildung; transformieren, umformen, umbilden …   Kleines Konversations-Lexikon