patients with keratoconus constitute a large proportion of patients suffering from anterior segment disorders. as of this time, however, its pathogenesis has not yet been elucidated. a reduction in cross-link between collagen molecules has been observed in keratoconic eyes as compared to normal ones. present approaches only address refractive errors resulting from the abnormal abnormal corneal ...

purpose : to compare the protection of eyes against visible light (vl) and ultraviolet radiation (uvr) by sunglasses available through the iranian optician trade ::::union:::: (iotu) shops and those provided by miscellaneous vendors. methods : totally, 353 pairs of sunglasses, including 188 pairs from iotu shops and 165 pairs from miscellaneous vendors were selected based on systematic random s...

The characterization of the time structure of ultrafast photon pulses in the extreme-ultraviolet (EUV) and soft X-ray spectral ranges is of high relevance for a number of scientific applications and photon diagnostics. Such measurements can be performed following different strategies and often require large setups and rather high pulse energies. Here, high-quality measurements carried out by ex...

background: the goal was to upgrade and/or uprate the traditional non-contact array by producing few modifications in the configuration of this model in order to maximize light receiving of water from the uv lamp and a better disinfection.  methods: an innovative non-contact model was made with a design based on irradiation of water, which was flowing as two thin waterfalls around a uv lamp in ...

Based on an analysis of all low resolution spectra of HD 89353 (HR 4049) obtained with the International Ultraviolet Explorer (IUE) over several years and uniformly reprocessed, we report on large ultraviolet variations for this star whose amplitude increases towards long wavelengths. Ultraviolet maximum and minimum occur respectively at phase 0.52 and 0.92 of Waelkens et al. (1991) ephemeris w...

Regarding the outdoor behavior of the Caucasian population, modern sunscreens should provide high and broad-spectrum ultraviolet protection in the ultraviolet B as well as in the ultraviolet A range and should be photochemically stable for ultraviolet doses, which can be expected in solar radiation. At present an assessment of the photostability of suncare products is not a general requirement ...

Articles you may be interested in Effect of vacuum-ultraviolet irradiation on the dielectric constant of low-k organosilicate dielectrics Appl. Bandgap measurements of low-k porous organosilicate dielectrics using vacuum ultraviolet irradiation Appl. The effects of plasma exposure and vacuum ultraviolet irradiation on photopatternable low-k dielectric materials Effect of vacuum ultraviolet and ...

Introduction: Protection against harmful effects of ultraviolet radiation (UV) is measured under Ultraviolet Protection Factor (UPF) scale. The utilization of protective clothing is the best way to deal with the damage caused by ultraviolet radiation. The purpose of this study was to compare the ultraviolet ray protective factor of pure cotton and cotton coated with ti...

on photosynthetic competence or light-interception. It is concluded that O 3 depletion and the concurrent rise This critical review of recent literature questions earlin UV-B irradiance is not a direct threat to photosynier predictions that photosynthetic productivity of thetic productivity of crops and natural vegetation. higher plants is vulnerable to increased ultraviolet-B (UV-B) radiation ...