نتایج جستجو برای: uv radiation
تعداد نتایج: 299907 فیلتر نتایج به سال:
The effect of ultraviolet (UV) radiation on the infectivity of Taenia taeniaejormis eggs was observed. The eggs were exposed to various UV doses and orally inoculated to rats. The number of cysts and lesions decreased dose-dependently, and neither cyst nor lesion was observed from rats infected with eggs exposed to a total dose of 2,880 mJ/cm or more. For evaluation of protective role of embryo...
Basal cell nevus syndrome (BCNS) is an autosomal dominant genetic disorder in which the afflicted individuals are extremely susceptible to sunlight-induced skin cancers, particularly basal cell carcinomas. However, the cellular and molecular basis for BCNS is unknown. To ascertain whether there is any relationship between genetic predisposition to skin cancer and increased sensitivity of somati...
Ultraviolet-B (UV-B) radiation present in sunlight is an important trigger of photomorphogenic acclimation and stress responses in sessile land plants. Although numerous moss species grow in unshaded habitats, our understanding of their UV-B responses is very limited. The genome of the model moss Physcomitrella patens, which grows in sun-exposed open areas, encodes signaling and metabolic compo...
The trace gas ozone, produced in the present-day stratosphere, acts as a screen for UV radiation between 195 and approximately 290 nm, depending on its column abundance. On the anoxic Archaean Earth, such an ozone screen would not have existed. Although the presence of other screens, such as an organic haze, might have ameliorated the UV radiation flux, even assuming the worst-case scenario (no...
The effect of ultraviolet B (UV-B) radiation on the thermal sensitivity of cucumber (Cucumis sativus L.) was studied using UV-B-sensitive cv Poinsett 76 and UV-B-resistant cv Ashley grown under control and elevated (300 mW m-2) UV-B radiation levels. Using both cotyledon and leaf discs, the ability of the tissue to reduce triphenyl tetrazolium chloride (TTC) was determined after treatment at 50...
Most of the positive effects of solar radiation are mediated via ultraviolet-B (UVB) induced production of vitamin D in skin. However, several other pathways may exist for the action of ultraviolet (UV) radiation on humans as focused on in this review. One is induction of cosmetic tanning (immediate pigment darkening, persistent pigment darkening and delayed tanning). UVB-induced, delayed tanni...
The impacts of UV irradiation, gamma irradiation, and a combination of both on Escherichia coli inactivation in primary and secondary wastewater effluents were investigated. UV doses of 35 and 62 J/m(2) were required for a 1-log inactivation of E. coli in the primary and secondary wastewater samples, respectively. A gamma dose of 170 Gy (J/kg) was required for a 1-log inactivation of E. coli in...
Research has shown that some plants respond to enhanced UV-B radiation by producing smaller and thicker leaves, by increasing the thickness of epidermis and concentration of UV-B absorbing compounds of their surface layers and activation of the antioxidant defence system. The response of high-altitude plants to UV-B radiation in controlled conditions is often less pronounced compared to low-alt...
Ultraviolet-B (UV-B) radiation can have wide-ranging impacts on plants. UV-B exposure can decrease the rate of photosynthesis, alter pigment concentrations, and damage DNA, proteins, and lipids; however, not all species are equally sensitive. Lemna minor and Spirodela polyrhiza, two sympatric aquatic plants, were exposed to 5 or 11 days of artificial UV-B radiation for 6 hours per day, and moni...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید