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 aims of the study are to determine the radioactivity concentrations of 226Ra, 238U, 232Th and 40K in vegetables of a recently found high background radiation area of south-eastern part of Bangladesh and to detect the radiological risks to human from intake of these vegetables. Materials and Method: 10 plant samples were collected randomly from different locations of the study ar...

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...

Purpose The projected existence and magnitude of carcinogenic effects ionizing radiation at low doses low-dose rates is perhaps the most important issue in protection today. Studies childhood cancer natural background have potential to throw direct light on this question, into a dose range below few tens mSv. This paper describes studies that been undertaken their context, discusses some proble...

Introduction: Annual effective radiation dose from all natural sources is approximately about 2.4 mSv and contribution of unnatural or man-made sources is 0.8 mSv. In some places of Ramsar, radiation dose due to radon exposure is about 3700 Bqm -3 while according to US EPA instruction radon levels should be 200 Bq m-3. Amazingly, there is not a meaningful result in the studies...