Solar ultraviolet (UV) radiation is a well recognized epidemiologic risk factor for melanoma and non-melanoma skin cancers. This observation has been linked to the accumulation of UVB radiation-induced DNA lesions in cells, and that finally lead to the development of skin cancers. Earlier, we have shown that topical treatment of skin with silymarin, a plant flavanoid from milk thistle (Silybum ...

While structurally complex benthic egg capsules can lower the vulnerability of gastropod embryos to a variety of environmental risks, including predation, desiccation, osmotic shock, and bacterial attack, little is known about their ability to shield embryos from ultraviolet radiation (UV) I examined the exposure of benthic egg capsules of the marine intertidal gastropod Nucella emarginata to s...

We report on development of tunable, cw, single frequency ultraviolet (UV) source based on intra-cavity frequency doubling of an optical parametric oscillator (OPO). The singly resonant OPO (SRO) is realized using 25 mm long MgOdoped periodically poled stoichiometric lithium tantalite (MgO:sPPLT). The SRO, pumped in the green, is intra-cavity frequency doubled using two different crystals β-BaB...

UV-B radiation is an important part of the electromagnetic spectrum emitted by the sun. For much of the period of biological evolution organisms have been exposed to UV radiation, and have developed diverse mechanisms to cope with this potential stress factor. Roots are usually shielded from exposure to UV by the surrounding soil, but may nevertheless be exposed to high energy radiation on the ...

BACKGROUND There are large geographic gradients in mortality rates for a number of cancers in the U.S. (e.g., rates are approximately twice as high in the northeast compared with the southwest). Risk factors such as diet fail to explain this variation. Previous studies have demonstrated that the geographic distributions for five types of cancer are related inversely to solar radiation. The purp...

Increases in the terrestrial levels of ultraviolet-B (UV-B) radiation (280 to 320 nm) due to diminished stratospheric ozone have prompted an investigation of the protective mechanisms that contribute to UV-B tolerance in plants. In response to UV-B stress, flowering plants produce a variety of UV-absorptive secondary products derived from phenylalanine. Arabidopsis mutants with defects in the s...

The radiation emitted by the sun known as ultraviolet radiation is related to several problems that might affect the human being. Most of times, people are well warned about the effects caused to the skin by the solar radiation overexposure but not about the effects to their eyes. This work aims at developing a real time ultraviolet (UV) index meter and a series of information systems that can ...

Novotná K., Klem K., Holub P., Rapantová B., Urban O. 2016: Evaluation of drought and UV radiation impacts on above-ground biomass of mountain grassland by spectral reflectance and thermal imaging techniques. – Beskydy, 9 (1–2): 21–30 Drought represents one of the major factors limiting productivity of managed and natural ecosystems. Under natural field conditions drought is often associated wi...

Optical radiation extends between microwaves and X-rays of the electromagnetic radiation and includes ultraviolet (UV), visible light (VL) and infrared (IR) components. The dose of radiation that reaches the skin is influenced by the ozone layer, position of the Sun, latitude, altitude, cloud cover and ground reflections. The photobiological effects of UV, VL and IR bands depend on their wavele...

The primary cause of non-melanoma skin cancer, the most prevalent form of human neoplasia, is the ultraviolet (UV) radiation found in sunlight. Exposing mice to UV radiation induces skin cancers that are highly antigenic. Upon transfer of an UV-induced skin cancer to a normal syngeneic mouse, the tumor cells are recognized and rapidly destroyed by the immune system of the recipient. This raises...