We observed the Seyfert 1 galaxy NGC 3516 twice during the flight of Astro-2 using the Hopkins Ultraviolet Telescope aboard the space shuttle Endeavour in March 1995. Simultaneous X-ray observations were performed with ASCA. Our far-ultraviolet spectra cover the spectral range 820–1840 Å with a resolution of 2–4 Å. No significant variations were found between the two observations. The total spe...

A flying spot ultraviolet microscope, employing a fast scan and pulsed operation of the raster, has been used to induce radiation damage in ascites tumor slide cultures, and to study by time-lapse cinematography the progressive stages of cell damage. The cells observed came from a strain (EFT) of the Ehrlich ascites carcinoma. Irradiated cells were found to show a characteristic syndrome of dam...

background: light is an important and adjustable physical factor in the job environment.this study aimed to determine the intensity of natural and mixed light and also the level of ultraviolet radiation in libraries and computer sites of ilam universities in spring 2011.   methods: in this cross-sectional study, 10 libraries, 16 study saloons, and 7 computer sites were selected. luminosity asse...

We have examined the functional architecture of the turtle Pseudemys scripta elegans retina with respect to colour processing, extending spectral stimulation into the ultraviolet, which has not been studied previously in the inner retina. We addressed two questions. (i) Is it possible to deduce the ultraviolet cone spectral sensitivity function through horizontal cell responses? (ii) Is there e...

Lithium disilicate nano-powders were synthesized via a mild condition hydrothermal reaction at 180 ºC for 48 and 72 h with a non stoichiometric1:2 Li:Si molar ratio in NaOH aqueous solution using Li2CO3 and SiO2.H2O as raw materials. The synthesized materials were characterized by powder X-ray diffraction (PXRD) technique and Fourier transform infrared (FTIR) spectroscopy. The XRD data showed t...

CONTEXT Skin cancer is a preventable and commonly diagnosed cancer in the U.S. Excessive ultraviolet radiation exposure is a known cause of skin cancer. This article presents updated results of two types of interventions evaluated in a previously published Community Guide systematic review: multicomponent community-wide interventions and mass media interventions when used alone. EVIDENCE ACQU...

BACKGROUND The role played by vitamin D in atopic dermatitis is controversial and has been the focus of many studies. The ultraviolet index has not been considered in this type of research. OBJECTIVES The objectives of the study were to assess 25-hydroxy vitamin D [25(OH)D] serum level in atopic dermatitis patients and control group, to investigate the association between atopic dermatitis cl...

The formation of fatty acid esters of vitamin D3 was demonstrated in rat skin exposed to artificial ultraviolet rays by using multi-dimensional high-performance liquid chromatography, ultraviolet spectrophotometry, and gas-liquid chromatography-mass spectrometry. This result indicated that the fatty acid esters of 7-dehydrocholesterol in rat skin (at least 80% of 7-dehydrocholesterol in rat ski...

background: given the increasing importance of suspended particles and reporting weather conditions in the amount of ultraviolet radiation in many countries, in this study, the data of the maximum amounts of pollution by suspended particles with the size of 10, 2.5 and1 microns (pm10, pm2.5, pm1) which were reported in 1-hour time-series and global ultraviolet index (uvi) were used to predict t...

cerium oxide (ceria) nano particle, as photodegradation prevention agent was studied in water-based polyurethane clear coat  systems. polyurethane coatings show superior weathering resistance compared with acrylic melamine systems. however, any chemical change has detrimental effects on the property profile of pu coatings. coatings containing various amounts of cerium oxide nanoparticles were p...