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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 ?
The data include the same three exams that were used for the primary beam exposure and two more: the supine abdomen exam, which is frequently ordered for inpatients, and the lateral spot L-spine exam, which requires the most radiation to produce an image.
During pelvic x-ray examination, the gonads, the organ with the highest tissue weighting factor, (15) are located in the primary beam or very close to it.
Correction procedures are not always available for the chosen experimental setting; most commercially available software packages can deal only with a circular beam and with specimens of round shape or such that the whole primary beam is intercepted for all values of [psi] and 2[theta], conditions not always met in normal laboratory practice (e.
Lead aprons cannot effectively stop primary beam photons.
In general, all intensity maps which were obtained from measurements with the primary beam normal to FD are quite symmetrical around the middle of the cross section, whereas intensity maps derived from measurements with the primary beam either in or against FD are rather unsymmetrical [ILLUSTRATION FOR FIGURE 4 OMITTED].
The inevitable gas scattering, both elastic and inelastic, of a fraction of the primary beam electrons has a significant and frequently severe impact on both qualitative and quantitative Si-EDS x-ray microanalysis in the VPSEM-ESEM.
46-inch copper and an FDA/NEXT fluoroscopic phantom that fully covered the primary beam.
Once the user enters the values for slab thickness and secondary beam spacing, the app will calculate the maximum permissible spacing for his primary beams and props, with the associated prop loads and maximum cantilever length.
The dimensions of the girders are increased from 500x300mm to 600x300mm and the dimensions of the primary beams are increased from 450x250mm to 500x300mm: approximately a 70% increase.
This lowers the panels and primary beams that hold the panels.
The form of the precast capitals is, it suggests, derived directly from the problems of making structural and services connections with the primary beams and ducts of the roof structure.
The work of reinforcing the structure has mainly consisted of bracing the primary beams and struts, and increasing the length of the secondary beams under the platform.