| LASER | Light Amplication by Stimulated Emission of Radiation |
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| PET | Positron Emission Tomography |
| SET | Singlephoton Emission Tomography = SPECT |
| SPECT | Single Photon Emission Computed Tomography = SET |
| DLE | delayed light emission; dialyzable leukocyte extract; discoid lupus erythematosus; disseminated lupu... |
| electron cyclotron emission | <physics, radiobiology> As electrons gyrate around in a magnetic field (see also larmor radius or cyclotron radius), they radiate radio-frequency electromagnetic waves. This is known as electron cyclotron emission, and can be measured to help diagnose a plasma. (09 Oct 1997) |
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| emission | 1. The act of sending or throwing out; the act of sending forth or putting into circulation; issue; as, the emission of light from the sun; the emission of heat from a fire; the emission of bank notes. 2. That which is sent out, issued, or put in circulation at one time; issue; as, the emission was mostly blood. 3. <physics> Emission theory, the theory of Newton, regarding light as consisting of emitted particles or corpuscles. See Corpuscular theory. Origin: L. Emissio: cf. F. Emission. Source: Websters Dictionary (01 Mar 1998) |
| emission-computed tomography | <radiology> Tomography using emissions from radionuclides and a computer algorithm to reconstruct the image. (20 Jun 2000) |
| emission electron | <physics>? A beta particle resulting from radioactive decay. (05 Mar 2000) |
| emission offset | <chest medicine> A reduction in the air pollution emissions of existing sources to compensate for emissions from new sources. (05 Dec 1998) |
| emission standard | This regulatory value is a quantitative limit on the emission or discharge of a potentially toxic substance from a source. The simplest form for regulatory purposes is a uniform emission standard (UES) where the same limit is placed on all emissions of a particular contaminant. (09 Oct 1997) |
| field-emission microscope | <instrument, microscopy> Either one of two kinds of point-projection microscopes, both invented by E. W. Muller: (1) The older device (1936) is a specialised cathode-ray tube, employing field-emission of electrons from a negatively charged tip of a very sharp needle in a vacuum, by point-projection of the image onto a positively charged, fluorescent screen. (2) A later device (field-ion-mission microscope, 1950) emits absorbed helium ions from an anode. (05 Aug 1998) |
| field emission tube | An X-ray tube that uses a cold cathode, relying on the tube voltage to pull electrons from it to the anode. (05 Mar 2000) |
| flame emission spectrophotometry | Determination of the concentration of an element by measurement of light emitted when the element is excited by energy in the form of heat. (05 Mar 2000) |
| remission, spontaneous | A spontaneous diminution or abatement of the symptoms of a disease. (12 Dec 1998) |
| rupture, spontaneous | Tear or break of an organ, vessel or other soft part of the body, occurring in the absence of external force. (12 Dec 1998) |
| presenile spontaneous gangrene | Gangrene occurring in middle life as a result of thromboangiitis obliterans. (05 Mar 2000) |
| spontaneous | 1. Proceding from natural feeling, temperament, or disposition, or from a native internal proneness, readiness, or tendency, without constraint; as, a spontaneous gift or proportion. 2. Proceeding from, or acting by, internal impulse, energy, or natural law, without external force; as, spontaneous motion; spontaneous growth. 3. Produced without being planted, or without human labour; as, a spontaneous growth of wood. Spontaneous combustion, combustion produced in a substance by the evolution of heat through the chemical action of its own elements; as, the spontaneous combustion of waste matter saturated with oil. Spontaneous generation. <biology> See Generation. Synonym: Voluntary, uncompelled, willing. Spontaneous, Voluntary. What is voluntary is the result of a volition, or act of choice; it therefore implies some degree of consideration, and may be the result of mere reason without excited feeling. What is spontaneous springs wholly from feeling, or a sudden impulse which admits of no reflection; as, a spontaneous burst of applause. Hence, the term is also applied to things inanimate when they are produced without the determinate purpose or care of man. "Abstinence which is but voluntary fasting, and . . . Exercise which is but voluntary labour." "Spontaneous joys, where nature has its play, The soul adopts, and owns their firstborn away." (Goldsmith) Sponta"neously, Sponta"neousness. Origin: L. Spontaneus, fr. Sponte of free will, voluntarily. Source: Websters Dictionary (01 Mar 1998) |
| spontaneous abortion | The sudden unplanned evacuation of the uterus. (27 Sep 1997) |
| spontaneous agglutination | The non-specific clumping of organisms in saline related to lack of polar groups in electrolyte solution. (05 Mar 2000) |