Solar ultraviolet radiation (UVR) can reduce the photosynthesis and growth of benthic diatom communities in shallow freshwater. Nevertheless, greater amounts of algae accumulate in UVR-exposed habitats than in UVR-protected environments. Near-ultraviolet (UVA wavelengths of 320 to 400 nanometers) and mid-ultraviolet (UVB, wavelengths of 280 to 320 nanometers) radiation also inhibit algal consum...

BACKGROUNDS Ultraviolet radiation B (UVRB) is the most important environmental factor capable of altering the immune function of human skin. OBJECTIVE To evaluate the association of the phenotypes of susceptibility or resistance to ultraviolet radiation B (UVRB) and the polar forms of leprosy. MATERIAL AND METHODS We evaluated 38 patients with lepromatous leprosy (LL) and 87 patients with t...

Several experiments have shown that ambient ultraviolet-B radiation (UV-B) has negative effects on the development of amphibians' embryos. We studied the effects of UV-B radiation on development, survival and frequency of deformity during egg development in the Natterjack toad (Bufo calamita) from a semiarid region of Lleida (Catalonia, Spain). Eggs exposed to ambient levels of UV-B and those p...

OBJECTIVES Seasonal variations in ultraviolet B (UVB) radiation cause seasonal variations in vitamin D status. This may influence immune responses and play a role in the seasonality of influenza. METHODS Pandemic and non-pandemic influenzas in Sweden, Norway, the USA, Singapore, and Japan were studied. Weekly/monthly influenza incidence and death rates were evaluated in view of monthly UVB fl...

A simultaneous comparison of human exposure to solar ultraviolet radiation at two locations was performed to study the effect of environmental factors and human attitudes on personal ultraviolet exposure. The study took place on 29 October 1996 in Toowoomba (27.5 degrees S, 151.9 degrees E) and Brisbane (27.4 degrees S, 153.1 degrees E), Queensland, Australia. From the data collected by calibra...

the role of the antioxidant defense system was studied in brassica napus, and subjected todifferent supplementary bands of ultraviolet radiation (uv-a, uv-b and uv-c). this study showed thatuv-b and uv-c induced oxidative stress as evidenced by an increase in lipid peroxidation and totalascorbate content. under uv-b and uv-c treatments, flavonoids and anthocyanins were increasedsignificantly co...

A growth-chamber experiment was conducted to evaluate whether ethylenenediurea (EDU), a chemical shown to be protective against ozone pollution, could ameliorate foliar damage induced by ultraviolet-B (UV-B) radiation exposure in 'Roanoke' soybean (Glycine max L.), a UV-B-sensitive cultivar, and whether these effects could be discriminated using fluorescence (F) observations. The experiment had...

ABSTRACT Background: Ultraviolet radiation is present in sunlight. If ultraviolet radiation exceeds the limit, it can cause detrimental effects on human health such as skin cancer and cataract. Materials and Methods: In this descriptive cross-sectional study, the level of solar ultraviolet radiation type A (UVA) were measured using UV LOG HAND HELD in Kermanshah city. The intensity of ultravio...

water deficit, ultraviolet radiation and carbon dioxide enrichment are the most important environmental factors in global climate change. this research was conducted in tarbiat modares university, research greenhouse and the objective of that was to study the effects of three levels of carbon dioxide (500, 900 and 1300 ppm), uv-radiation (uv-a, b and c with intensity of 18, 25 and 40 µw.cm2 res...

Introduction: Solar energy is one of the free sources, clean and environmentally friendly energy. Sun is the most important source of natural ultraviolet radiation that has a major role in the life of living beings. Industrial and medical applications of ultraviolet radiation have been clearly proven, like the production of vitamin D or treatment of many diseases, and also har...