BACKGROUND The Global Solar Ultraviolet Index (UVI) is a health communication tool used to inform the public about the health risks of excess solar UV radiation and encourage appropriate sun-protection behaviour. Knowledge and understanding of the UVI has been evaluated among adult populations but not among school students. OBJECTIVES To draw on previously unpublished data from two school-bas...

Ultraviolet light-emitting diodes (UV-LEDs) have started replacing UV lamps. The power per LED of high-power LED products has reached 12 W (14 A), which is 100 times the values observed ten years ago. In addition, the cost of these high-power LEDs has been decreasing. In this study, we attempt to understand the technologies and potential of UV-LEDs.

BACKGROUND Studies suggest that low levels of vitamin D may be associated with prostate cancer, and darker skin reduces the body's ability to generate vitamin D from sunshine. The impact of sunshine on racial disparities in prostate cancer incidence and mortality is unknown. METHODS Using the Surveillance, Epidemiology, and End Results program database, the authors calculated age-adjusted pro...

The first direct measurement of the dispersive part of the refractive index is performed at extreme ultraviolet (EUV) wavelengths, where absorption is higher as compared with hard x-ray and visible wavelengths. A novel diffractive optical element, which combines the functions of a grating and a zoneplate, is fabricated following Fourier optical techniques and employed here for the first time at...

The Geotail satellite has been operating for almost two solar cycles (~23 years) since its launch in July 1992. The satellite carries the energetic particle and ion composition (EPIC) instrument that measures the energetic ion flux (9.4– 212 keV/e) and enables the investigation of long-term variations of the ion composition in the plasma sheet for solar cycles 22–24. From the statistical analys...

The Global Solar UV Index was developed as an easyto-understandmeasure of the amount of biologically-effective ambient solar ultraviolet radiation (UVR) at different locations on the earth’s surface. Over the past few years, questions have been raised about the global applicability of the UV Index, about the evidence base for exposure risk thresholds and related protective measures, and about w...

A study of the ultraviolet continuum variability (Paltani & Courvoisier 1994) has shown that the relative variability of quasars and Seyfert galaxies decreases when the luminosity increases. The spectral information included in the IUE spectra allows us to study this dependence in the rest frame of the objects. The trend is strengthened by the general property that active galactic nuclei varymo...

To the best of our knowledge, the first direct measurement of the dispersive part of the refractive index is performed at extreme-ultraviolet (EUV) wavelengths, where absorption is higher as compared with hard-x-ray and visible wavelengths. A novel diffractive optical element that combines the functions of a grating and a zone plate is fabricated with Fourier optical techniques and employed her...

Effects of ultraviolet-B radiation on the photosynthesis of seagrasses (Halophila engelmanni Aschers, Halodule wrightii Aschers, and Syringodium filiforme Kütz) were examined. The intrinsic tolerance of each seagrass to ultraviolet-B, the presence and effectiveness of photorepair mechanisms to ultraviolet-B-induced photosynthetic inhibition, and the role of epiphytic growth as a shield from ult...

BACKGROUND Climate and sunlight (ultraviolet radiation) influence activity of atopic eczema. OBJECTIVE To evaluate the effect of moving from a subarctic/temperate climate to a sunny subtropical climate on children's atopic eczema. METHODS Children, 4-13 years, with severe atopic eczema were randomized to stay 4 weeks in Gran Canary (index patients = 30) and home in Norway (controls = 26), w...