We analyzed a number of cases about the Linac troubles in our hospital and have examined the effect of preventive maintenance with Weibull analysis and exponential distribution from April 2001 to March 2012. The total failure by irradiation disabled was 1, 192. (1) Medical linear accelerator (MLC) system was 24.0%, (2) radiation dosimetry system 13.1%, and the (3) cooling-water system was 26.5%...

Deinococcus radiodurans has an efficient DNA double strand break (DSB) repair mechanism, which helps it to mend hundreds of DSBs produced after exposure to the exceptionally high doses of ionizing radiation and shows no measurable loss of cell viability. This tolerance is well above the DSB tolerance by any other organism. The better catalytic efficiency of different proteins associated with DS...

We investigate the behavior of the test ideal of an excellent reduced ring of prime characteristic under base change. It is shown that if h : A ?! D is a smooth homomorphism, then A D = D , assuming that all residue elds of A at maximal ideals are perfect and that formation of the test ideal commutes with localization. It is also shown that if h : (A; m) ?! D is a nite at homomorphism of Gorens...

The effect of ultraviolet radiation on a cell line established from the warm water fish Tilapia has been assessed by measuring the rate of DNA synthesis, excision repair, post-replication repair and cell survival. The cells tolerate ultraviolet radiation better than mammalian cells with respect to DNA synthesis, post-replication repair and cell survival. They are also efficient in excision repa...

As a vibration- free concrete, self- compacting concrete (SCC) can be easily used in the absence of consolidation, therefore; it is a good option for repairing and retrofitting concrete structures. The quality of repair layer is highly effective on a successful repair. Accordingly, in this study, factors affecting the quality of fiber-reinforced self-compacting concrete repair layer, including ...

Background: Exposure to ionizing radiation is known to induce oxidative stress followed by damage to critical biomolecules like lipids, proteins and DNA through radiolysis of cellular water. Since radiation has been widely used as an important tool in therapy of cancer, the detailed investigation regarding the DNA damage and repair kinetics would help to predict the radiation sensitivity of cel...

background: exposure to ionizing radiation is known to induce oxidative stress followed by damage to critical biomolecules like lipids, proteins and dna through radiolysis of cellular water. since radiation has been widely used as an important tool in therapy of cancer, the detailed investigation regarding the dna damage and repair kinetics would help to predict the radiation sensitivity of cel...

pediatric neurological disorders including muscular dystrophy, cerebral palsy, and spinal cord injury are defined as a heterogenous group of diseases, of which some are known to be genetic. the two significant features represented for stem cells, leading to distinguish them from other cell types are addressed as below: they can renew themselves besides the ability to differentiate into cells wi...

background and aims. a proper bond must be created between the existing composite resin and the new one for successful repair. the aim of this study was to compare the effect of three mechanical surface treatments, using diamond bur, air abrasion, and er,cr:ysgg laser, on the repair bond strength of the silorane-based composite resin. materials and methods. sixty cylindrical composite resin spe...

objective: to evaluate the feasibility and results of using serosal patch of small bowel for repair and replacement of inferior vena cava (ivc) after resection of a part of infra-renal ivc in an animal model, as it may be encountered in extensive tumors of retroperitoneal and trauma patients. methods: five healthy sheep of both sexes were prepared. after general anesthesia and laparotomy, a def...