background: radiotherapy plays an important role in the management of most malignant and many benign primary central nervous system (cns) tumors. radiotherapy affects both tumor cells and uninvolved normal cells; so, it is important to estimate absorbed dose to organs at risk in this kind of treatment. the aim of this study was to determine the absorbed dose to chiasma, lens, optic nerve, retin...

The study assessed the radiological risks associated with the presence of natural and artificial radionuclides in the Bory Stobrawskie forests (PL). Using the conversion factors given by UNSCEAR and the measurements results of (232)Th series, (238)U series, (40)K, and (137)Cs specific activities in the 10-cm soil layer the values of absorbed dose (D) and the annual effective dose equivalent der...

The applications that cover the use of ionizing radiation are numerous, very diverse and belong to several fields activity such as, medical agricultural etc. aim this work is highlight an application decorative glass coloring by gamma radiation. Crystal white cups placed on small rotating tables subjected exposure from cobalt-60 irradiator National Institute Agronomic Research (INRA-Morocco / T...

introduction: average glandular dose calculation in mammography with mo-rh target-filter and dose calculation for different situations is accurate and fast. material and methods: in this research, first of all, x-ray spectra of a mo target bombarded by a 28 kev electron beam with and without a rh filter were calculated using the mcnp code. then, we used the sobol-wu parameters to write a fortra...

This work illustrates a procedure to assess the overall accuracy associated with Gamma Knife treatment planning using plugging. The main role of source plugging or blocking is to create dose falloff in the junction between a target and a critical structure. We report the use of MAGAT gel dosimeter for verification of an experimental treatment plan based on plugging. The polymer gel contained in...

Advances of radiation delivery devices have increased the complexity oncology treatments. Herewith, outcome treatment, as well patient safety, strongly depend on consistency absorbed dose delivery. Both can be ensured by comprehensive system verification calculated distributions. Standard method is evaluation distribution according to gamma method, using a 2-D detector and homogeneous phantom, ...

The surveys of natural gamma-emitting radionuclides in rocks and soils from the Ezine plutonic area were conducted during 2007. Direct dose measurement using a survey meter was carried out simultaneously. The present study, which is part of the survey, analysed the activity concentrations of U, Th and K in granitoid samples from all over the region by HPGe gamma spectrometry. The activity conce...

Absorbed dose to water in a cobalt-60 gamma-ray beam has been determined using a thick-walled graphite ionization chamber. The chamber was calibrated in a graphite phantom against a graphite calorimeter, and the graphite calibration factor was converted to a water calibration factor using published energy absorption coefficient ratios and a measured replacement factor. Comparisons between the g...

Coals mined in some regions of the Transdanubian Middle Mountains in Hungary have elevated concentrations of Ra. The slags and ashes derived from these coals have been used as building material for schools and kindergartens. As the Ra reached up in these waste products of coal-firing systems, the gamma dose contribution in the buildings, which contained them, was calculated. In these places the...