background: the activity concentrations of some radionuclides in soil samples collected from 20 locations in 8 major towns in oyo state, southwestern nigeria have been determined by gamma-ray spectrometry technique. materials and methods: the activity concentrations were determined using high-purity germanium (hpge) detector (canberra industries inc.). the outdoor absorbed dose rates in air at ...

INTRODUCTION Gold nanoparticles have been used as radiation dose enhancing materials in recent investigations. In the current study, dose enhancement effect of gold nanoparticles on tumor cells was evaluated using Monte Carlo (MC) simulation. METHODS We used MCNPX code for MC modeling in the current study. A water phantom and a tumor region with a size of 1×1×1 cm3 loaded with gold nanopartic...

background: human is exposed to radiation in their environment with or without their consent and the exposure to natural background radiation is an unpreventable event on earth. materials and methods: an in situ assessment of the indoor and outdoor background radiation in akwanga and keffi towns of nasarawa state nigeria was carried out using a halogen-quenched geiger muller (gm) detector (insp...

ever since studies on uranium miners established the presence of a positive risk coefficient for the occurrence of lung cancer in miners exposed to elevated levels of 222rn and its progeny, there was a great upsurge of interest in the measurement of 222rn in the environment and considerable data is generated on the levels of 222rn in the environment across the worlds and is periodically reporte...

PURPOSE To determine the clinical utility of dual-energy computed tomography (CT) in evaluating solitary pulmonary nodules (SPNs). MATERIALS AND METHODS This study was approved by the institutional review board, and informed consent was obtained. CT scans were obtained before and 3 minutes after contrast material injection in 49 patients (26 men, 23 women; mean age, 60.39 years +/- 12.24 [sta...

Introduction: Radiation therapy is an important procedure for treatment of more than half of tumors. One way to increase the efficiency of radiation therapy is application of radiosensitizer at the site of tumor. gold nanoparticles (GNPs) have several characteristics that make them attractive for using with radiation therapy including small size (1–100 nm), biocompatibility, pr...

Background: Gold nanoparticles are emerging as promising agents for cancer therapy and are being investigated as drug carriers, photothermal agents, contrast agents and radiosensitisers.Objective: The aim of this study is to understand characteristics of secondary electrons generated from interaction of gold nanoparticles GNPs with x-rays as a function of nanoparticle size and beam energy and ...

Four children are reported in whom marked contrast enhancement of the spinal cord and roots was demonstrated by computed tomography months to years after relatively low dose therapeutic irradiation of paraspinal tumors, the radiation field including the cord. This phenomenon, previously unreported, probably represents subclinical radiation injury. None of the children had any neurologic abnorma...

Objective(s): Taking advantage of high atomic number of gold nanoparticles (GNPs) in radiation dose absorbing, many in vitro and in vivo studies have been carried out on using them as radio-sensitizer. In spite of noticeable dose enhancement by GNPs at keV energies, using this energy range for radiotherapy of deep-seated tumors is outdated. The aim of the present work was to examine the effect ...

conclusions the effective annual dose of interventionists who work in center 1 and 2 was 143.08 and 1226.78 msv respectively. the high radiation dose which delivers to the leg of physicians in center 2 can be an important cause of radiation dermatitis occurred on the leg of our interventionist. patient dose during most of the procedures was less than the threshold dose for occurring erythema bu...