In situ transmission electron microscopy (TEM) has been extensively applied to study radiation effects in a wide variety of materials, such as metals, ceramics and semiconductors and is an indispensable tool in obtaining a fundamental understanding of energetic beam-matter interactions, damage events, and materials' behavior under intense radiation environments. In this article, in situ TEM obs...

Growing interest in proton and heavy ion therapy has reinvigorated research into the fundamental biological mechanisms underlying the therapeutic efficacy of charged-particle radiation. To improve our understanding of the greater biological effectiveness of high-LET radiations, we have investigated DNA double-strand breaks (DSBs) following exposure of plasmid DNA to low-LET Co-60 gamma photon a...

7 9As. The 7 9As was prepared by irradiating metalic Se (enriched to 97 .8% in 8 0Se) in the linear accelerator of the C.B.P.F. The maximum energy of the bremsstrahlung beam was 22 MeV and irradiations were performed using up to 600 mg samples with irradiation times up to 30 min. The gamma-ray spectra were detected by a 2 cm 3 Ge(Li) diode. The pulses were fed via an O R T E C 1 0 9 preamplifie...

It is a frequent clinical, and less frequent labora tory, observation that a tumor subjected to a number of sublethal irradiations will gradually acquire radioresistance (5, 11). The usual manifes tation of acquired radioresistance by a tumor is the diminished amount of regression for the same dose, or the increased dose required for an equal amount of regression or for sterilization, as the ra...

It is a frequent clinical, and less frequent labora tory, observation that a tumor subjected to a number of sublethal irradiations will gradually acquire radioresistance (5, 11). The usual manifes tation of acquired radioresistance by a tumor is the diminished amount of regression for the same dose, or the increased dose required for an equal amount of regression or for sterilization, as the ra...

The relative rates of formation of four photonuclear reactions produced by 70 Mev X-ray irradiations of iron metal were measured. The reactions investigated were the Fe54( γ,pn)Mn52m, Fe54(γ,pn)Mn52, Fe54(γ,2n)Fe52 and Fe57(γ,p)Mn56. The manganese yields were determined by measuring the radioactive manganese chemically separated from the target material. It was found that the total (γ,pn) yield...

It is a frequent clinical, and less frequent labora tory, observation that a tumor subjected to a number of sublethal irradiations will gradually acquire radioresistance (5, 11). The usual manifes tation of acquired radioresistance by a tumor is the diminished amount of regression for the same dose, or the increased dose required for an equal amount of regression or for sterilization, as the ra...

It is a frequent clinical, and less frequent labora tory, observation that a tumor subjected to a number of sublethal irradiations will gradually acquire radioresistance (5, 11). The usual manifes tation of acquired radioresistance by a tumor is the diminished amount of regression for the same dose, or the increased dose required for an equal amount of regression or for sterilization, as the ra...