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Biomedical subjects

A M Ghose

Publications and source records attributed to A M Ghose.

5 recordsLinked to original sources
PubMed1988

Radiation field from a rectangular plaque source: critique of some engineering approximations.

Geometry-dependent effects upon the response of an omnidirectional detector and rectangular source configuration are reviewed. A survey of approximations is conducted and evaluation of regions of validity performed. A variant of the Wallace approximation is shown to produce values that do not vary from "exact" calculations by more than +/- 5%, often yielding results that are within +/- 1%.

Mathematics↗
PubMed1986

Photon absorptiometric studies of elements, mixtures and substances of biomedical interest.

Photon absorptiometric measurements of several elements, mixtures and substances of biomedical interest have been performed. The 144.5 keV photons of 141Ce and the associated x-ray emissions of 203Hg at 75 keV and 137Cs at 33 keV in addition to the more commonly applied energies of 279.2 and 661.6 keV respectively, have been utilised. The concept of effective atomic numbers and the choice of tissue-equivalent substitutes has been examined with reference to the experimental findings.

Animals↗
PubMed1984

Photon scattering in biomedically important elements.

A survey of recently published work on the biomedical and other applications of the ratios of coherent to incoherent scattering of gamma radiation off low Z elements has revealed that the functional dependence of any individual process is, for the most part, misrepresented. It is shown, by analysis of the available tabulated coherent and incoherent scattering functions, that an explicit power dependence of Z may not be easily expressed. Furthermore, Rayleigh scattering is much better represented by the modified form factor rather than the usual form factor approach. The quantities of interest in using the coherent to incoherent scattering intensity ratio have been identified and various parametrical procedures have been developed within the range of atomic number and momentum transfers of biomedical interest. Applications to bone mineral measurements are discussed and future investigations based upon recent, more accurate theoretical predictions of scattering cross-sections are suggested.

Animals↗