Adaptive responses were observed using the micronucleus frequency in bullfrog tadpoles. In tanks in which control tadpoles were placed in contact with tadpoles that were previously housed in tritiated water (3.0× 104 Bq/L), the cells from all animals responded as though they were “adapted”. This suggests that direct exposure to 3.0× 104 Bq/L tritium contributes to an increased resistance to a h...

The cancer of oral cavity is related to lesions of mucous membrane of tongue and gum that can be treated with radiation therapy. A lateral photon field can be used to treat this kind of tumor, which has a side-effect on normal tissue in the opposite side of the oral cavity. In this study the dosimetric effect of the various shields in oral cavity is evaluated. In this study, a special phantom s...

Cobalt is an integral part of the vitamin Bl2 complex and an important cofactor in enzyme systems (Lowman et al. 1971; Reichle et al. 1970). It is, therefore, an element whose cycle in oceanic ecosystems is of interest. The artificial radionuclide cobalt-60 (60CO) has been observed in the livers of albacore, (Thunnus alalunga Bonnaterre) collected off the west coast of North America, Washington...

We present COBS — a model of a concurrent object-based computational system with handshakes as elementary actions of inter-process communication. Processes are considered to be partial views of the system. Their communication by asynchronous message passing and variable sharing is modeled by elementary processes on the same abstraction level. The same acts of computation and communication can b...

Irradiation leads to immunosuppression, hemopoiesis injury as well as sub-health of human being. The protective and therapeutic effects of cuttlefish ink on hemopoiesis in 60Co gamma radiated model mice were investigated. One hundred and twenty female ICR mice aged 6 weeks (20-24g) were randomly divided into five groups: the control group, the model group, and the low, medium, high dosage group...

The aim of the present study was to investigate the effects of thalidomide, a drug known for its anti‑angiogenic and antitumor properties, at its cytotoxic dose previously determined as 40 µg/ml (according to four cytotoxic test results). The effect of the drug alone and in combination with radiotherapy using Cobalt 60 (60Co) at 45 Gy on the enzymatic activity of substance‑P degrading A disinte...

Beam quality correction, kQQ0(r), for solid-state detectors diamond, LiF, Li2B4O7, Al2O3, and plastic scintillator are calculated as a function of distance, r, along the transverse axis of the 60Co and 192Ir brachytherapy sources using the Monte Carlo- based EGSnrc code system. This study also includes calculation of detector-specific phantom scatter correction, kphan(r), for solid phantoms suc...

abstract  introduction: recently uses of medium and high energy x-rays has been increased in iran and radiotherapy centers along with a variety of accelerators have been installed in some provinces. in the other hand there is no sufficient skill in designing and making radiotherapy treatment rooms. this study was conducted to evaluate the efficacy of different mixtures of barite concrete for sh...