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BEAM

 
brain electric activity map; trademark name for a map of brainwave activity derived from a computerized enhancement of electroencephalographic records.

beam

 [bēm]
a unidirectional, or approximately unidirectional, emission of electromagnetic radiation or particles.
useful beam in radiology, that part of the primary radiation that is permitted to emerge from the tubehead assembly of an x-ray machine, as limited by the aperture or port and accessory collimating devices.
beam splitter a device that reflects light from the output phosphor of an image intensifier to a photographic recording. Called also image distributor.

beam

(bēm),
1. Any bar the curvature of which changes under load; in dentistry, frequently used instead of "bar."
2. A collimated emission of light or other radiation, such as an x-ray beam.
[O.H.G. Boum]

beam

Etymology: ME, beem, tree
1 a bedframe fitting for pulleys and weights, used in the treatment of patients requiring weight traction. See Balkan traction frame.
2 (in radiology) the primary beam of radiation emitted from the x-ray tube.

BEAM

[bēm, bē′ē′ā′em′]
abbreviation for brain electric activity map.

beam

Drug slang
A regional synonym for cocaine.
 
Radiation oncology
A focused stream of particles or electromagnetic radiation which is focused in a single direction or body region as part of a therapeutic regimen.

BEAM

Abbreviation for:
BCNU, etoposide, cytarabine, melphalan (a chemotherapy regimen)
Biomedical Equipment Assessment & Management (Medspeak-UK)
brain electrical activity mapping

beam

(bēm)
1. Any bar with a curvature that changes under load.
2. dentistry Synonym(s): bar (2) .
3. A collimated emission of light or other radiation, such as an x-ray beam.
[O.H.G. Boum]

beam

(bēm)
1. Any bar the curvature of which changes under load; in dentistry, frequently used instead of "bar."
2. A collimated emission of light or other radiation.
[O.H.G. Boum]

beam,

n a stream or approximately unidirectional emission of electromagnetic radiation or particles.
beam, central,
n the center of the beam of roentgen rays emitted from the tube.
beam, useful,
n the part of the primary radiation that passes through the aperture, cone, or other collimator.

beam

a unidirectional emission of electromagnetic radiation. See also x-ray.

external beam therapy
radiotherapy in which the source is at a distance from the patient, e.g. orthovoltage, cesium-137, cobalt-60 or linear accelerator.
beam limitation
restriction of the divergent beam as it appears from the tube window by a lead plate or cone or a light beam diaphragm located at the window.
primary beam
the radiation beam as it passes through the window of the x-ray tube and before it is modified by extra-tube devices.
References in periodicals archive ?
With the primary beam is detected, whether the intersection of the individual beams with surfaces, visible light sources.
The primary beam, leakage from the x-ray tube and scatter radiation from the patient must be taken into consideration.
496 nm beam at an angle of approximately 104[degrees] with respect to the primary beam.
Many Schenkerian graphic symbols, such as beamed open notes, are easy to achieve through the QuickChange command; split beams are also possible, but not "officially" so, for Nightingale will not break a primary beam - one must go through a process of creating a beamed group and then hiding some of the notes attached to the beam.
Among the topics are measuring residual stresses in surface treated stainless steel groove welds, evaluating arc evaporated coatings on rounded surfaces and sharp edged, residual stresses in dissimilar weld joints, the experimental analysis of shot peening on carburized for carbonitrided parts, measuring stress in aluminum using a Gbel mirror as the primary beam optics for an X-ray diffractometer, the thermal fatigue study of hardfaced hot forging tools using numerical analysis and residual stress evaluation, and investigating residual stress distribution in wheel rims using neutron diffraction.
During mammography, some X-rays scatter away from the primary beam in the breast and spread outward in different directions.
Among the topics are measuring residual stresses in surface treated stainless steel groove welds, evaluating arc evaporated coatings on rounded surfaces and sharp edged, residual stresses in dissimilar weld joints, the experimental analysis of shot peening on carburized for carbonitrided parts, measuring stress in aluminum using a Gobel mirror as the primary beam optics for an X-ray diffractometer, the thermal fatigue study of hardfaced hot forging tools using numerical analysis and residual stress evaluation, and investigating residual stress distribution in wheel rims using neutron diffraction.
2 m from the moderator is the primary beam shutter, which extends 1.
The response of the PET to the ablation process is much more nonlinear than crystallization or melting (11, 12); consequently, the diffracted radiation provides insufficient energy to etch the film surface in the manner of the primary beam.
Moreover, with RapidArc's highly efficient use of the primary beam, secondary stray radiation caused by scatter and leakage are reduced by over 50 percent on average compared with fixed field IMRT.
The laser beam passes through a beamsplitter oriented so that the first reflected beam strikes a monitor detector and the primary beam is transmitted to the test meter.