Risk prediction and dose limits for human radiation exposure are based on the assumption that risk is proportional to total dose. However, there is concern about the appropriateness of those limits for people who may be genetically cancer prone. The TP53 gene product functions in regulatory pathways for DNA repair, cell cycle checkpoints and apoptosis, processes critical in determining ionizing...

Development of radiation technology has resulted in increasing numbers of people working with it. Therefore it has increasingly been important to monitor the radiation in order to ensure public safety. Physical dosimetry plays an important role in monitoring. But a need arise for biological dosimetry where physical dosimetry is absent or its presence is insufficient. In this study Co-60 gamma r...

The Nuclear Regulatory Commission is amending its regulations to make minor corrections and clarifying changes to the NRC's 10 CFR Part 20, "Standards for Protection Against Radiation." The final rule is also intended to conform other regulations with the Commission's 1991 revised radiation protection requirements. In addition, the final rule includes a minor policy change that raises the monit...

Abstract—Regulatory bodies has proposed limits on Particulate Matter (PM) concentration in air; however, it does not explicitly indicate the incorporation of effects of toxicities of constituents of PM in developing regulatory limits. This study aimed to provide a structured approach to incorporate toxic effects of components in developing regulatory limits on PM. A four-step human health risk ...

Gold nanoparticles, because of their high radiation absorption coefficient and efficient generation of secondary photoelectrons, have been predicted to enhance therapeutic efficacy in radiation therapy. However, high dose for effective treatment limits their use. We have synthesized multifunctional gold nanoclusters (GNCs) that can be used for imaging and radiation therapy. The designed GNCs ha...

The accuracy of dose calculations at extended SSD is of significant importance in the dosimetric planning of total body irradiation (TBI). In a first step toward the implementation of electronic, multi-leaf collimator compensation for dose inhomogeneities and surface contour in TBI, we have evaluated the ability of the Eclipse AAA to accurately predict dose distributions in water at extended SS...

The possibility of using Brazilian stones in gamma high-dose dosimetry was investigated at IPEN using the optically stimulated luminescence (OSL) technique. Agate samples were studied in relation to their OSL dosimetric properties, in this work. The samples were irradiated at a Gamma-Cell system (Co). The calibration curves show a sublinear behavior between 50 Gy and 300 kGy, and the lower dete...

Binding of methadone in body tissues limits the rise in plasma concentration and prolongs the pharmacological action in patients receiving a daily maintenance dose. An opiate with equal intrinsic activity but greater binding affinity would, therefore, be a better drug than methadone for maintenance treatment; it would be safer when taken in a single dose and longer in its duration of action whe...

background: different kinds and models of personal dosimeters are used in individual monitoring by workers.  performance testing as part of approval procedures is carried out to demonstrate that the essential performance specifications are routinely maintained. there are four service providers in iran which use different luminescence techniques (i. e. tld and rpl) with various kinds of dosimete...

background: high level radiation areas have been recognized on various parts of the earth. mahallat hot spring region is one of these areas. study of exposure in these areas can be helpful in investigating the effects of ionizing radiation. internal and external exposure to the staff was studied. materials and methods: used materials and instruments include: rss-112 ionizing chamber for environ...