The γ-index test has been commonly adopted to quantify the degree of agreement between a reference dose distribution and an evaluation dose distribution. Monte Carlo (MC) simulation has been widely used for the radiotherapy dose calculation for both clinical and research purposes. The goal of this work is to investigate both theoretically and experimentally the impact of the MC statistical fluc...

Background: Assessment of activity concentrations of 238U, 232Th, 40K and gamma dose rate (DR) was carried out over a laterite mining field in Ilorin-south, Nigeria. Materials and Methods: A well calibrated Super-Spec (RS-125) gamma spectrometer was used to measure the activity concentrations of 40K, 238U, 232Th and gamma doses rate at 1 m above the ground level over the laterite mining field. ...

This note explores whether the lowest dose-rate mortality data from the beagle tissue archive might be consistent with the Linear No-Threshold (LNT) Model and might give evidence in favour of that model. I suggest that the answer may be ‘yes’; further statistical analysis will be required to establish how strongly the data favour LNT over alternative non-linear models. 1 The mortality data A pa...

introduction: skull base meningiomas constitute a large proportion of the meningiomas, which are the most common benign brain tumors. the treatment of skull base meningiomas is specially challenging and controversial due to the proximity of these tumors to the vital brain structures. radiosurgery is now emerging as an efficient alternative treatment modality which involves the ablation of tumor...

Radioresistant E. coli TGl harboring pUC 18 plasmid which was Ampicillin-resistant was exposed to 60Co gamma-rays or 3H beta-rays in saline to determine whether the relative biological effectiveness of 3H beta-rays is higher than one. After exposure to 60Co gamma-rays at a dose rate of 0.465 Gy/min, the D0 by colony formation was 145 Gy in the presence of Ampicillin in or absence from the agar ...

background: the aim of this work was to establish how well gel dosimeters performed, as substitutes for brain tissue compared with standard phantom materials such as water, polymethyl-methacrylate (or pmma), a150 plastic and te- liquid phantom material for dosimetry of neutron beams in boron neutron capture therapy. materials and methods: thermal neutron fluence, photon dose and epithermal neut...

The fluorescence of tryptophan residues of gramicidin A (gA), bound to phosphatidylcholine liposomes contains valuable information about local changes in the environment of the molecule induced by gamma radiation. With this work, we aim to demonstrate that the gamma radiation effect on the peptide involves the action of free radicals, derived from water radiolysis and the process of lipid perox...

Over the last 30 years there has been a reduction in the radioactive discharges from the UK’s Sellafield site. Radionuclide activity concentrations in the environment around Sellafield have declined as a result. However, routine monitoring results from the nearby Esk Estuary show a less clear trend, with fluctuations in gamma dose rate measurements being reported from year to year. A comprehens...

A mobile system comprising of a Geiger-Muller (GM) dosimeter connected with a smart phone was used for ambient gamma dose rate survey within the districts and on the roads within the state of Kuwait. While the dosimeter provides data on gamma dose rates, the smart phone provides the GPS navigation information and saves the data for subsequent analysis and mapping. The survey covered a total dis...