The average annual outdoor background radiation dosage across the study area was ∼two times greater than world average. Higher observed in indoor environments outdoors majority of sampling locations.

background: ionizing radiation is present in all environment of the earth’s surface, beneath the earth and in the atmosphere. human beings are exposed to external radiation from their surroundings naturally and also to internal radiation from food, water and air they consume. then, it is important to measure and develop knowledge about radiation. objective: this study is designed to evaluate th...

There is no place on the Earth, the planet we live on, where the natural background radiation level is zero. Since the birth and even in our fetal stage, we have been exposed to different sources of natural radiation. Life, in fact, evolved in a radiation environment that was much more harsh than today. Earth serves as a source of terrestrial radiation. Uranium, thorium, and radium are among th...

introduction guilan is one of the provinces in north of iran, with population of 2,480,874 and a total area of ​​14,042 square kilometers. this study assesses the outdoor natural gamma dose rates in the air of 49 cities in guilan and calculates corresponding average annual effective dose. materials and methods a total of 260 different sample points measurements were carried out. the results inc...

Exposure of the germ cells of living organisms to X-rays or to radium has so far proved to be the only reliable method for artificially inducing mutations, as shown by MULLER and others. In nature, organisms or groups of organisms carrying “favorable” mutations are supposed to be chosen for survival by the sorting action of natural selection, and MULLER and MOTT-SMITH (1930) have concluded that...

Adaptive radiations have long served as living libraries to study the build-up of species richness; however, they do not provide good models for radiations that exhibit negligible adaptive disparity. Here, we review work on damselflies to argue that nonadaptive mechanisms were predominant in the radiation of this group and have driven species divergence through sexual selection arising from mal...

background: the effect of natural background radiation on health is still controversial. however, it is clear that it depends on the dose received by the population. the estimation of external natural background gamma rays received by the population of caspian coastal provinces in the northern part of iran was the main goal of this study. materials and methods: gamma rays was measured using cal...

introduction the exposure of human beings to ionizing radiation from natural sources is a continuing and inescapable feature of life on earth. for most individuals, this exposure exceeds that from all man-made sources combined. materials and methods in this study, the annual effective dose in high level environmental background radiation areas (hlebras) of northern city of ramsar in iran was de...