Continuous depletion of the stratospheric ozone layer has resulted in an increase in ultraviolet-B (UV-B; 280-315 nm) radiation on the earth's surface which inhibits photochemical and photobiological processes. However, certain photosynthetic organisms have evolved mechanisms to counteract the toxicity of ultraviolet or high photosynthetically active radiation by synthesizing the UV-absorbing/s...

We have used archival ultraviolet (UV) imaging of 50 nearby star-forming galaxies obtained with the Ultraviolet Imaging Telescope (UIT) to derive integrated near-UV and far-UV magnitudes, and have combined these data with Hα, far-infrared, and thermal radio continuum measurements to explore the consistency of UV and Hα star formation rates (SFRs). In agreement with previous studies, we find tha...

We examined the wavelength dependence of ultraviolet (UV) ra-diation (UVR)-induced melanoma in a Xiphophorus backcross hybrid model previously reported to be susceptible to melanoma induction by ultraviolet A (UVA) and visible light. Whereas ultraviolet B (UVB) irradiation of neonates yielded high frequencies of melanomas in pigmented fish, UVA irradiation resulted in melanoma frequencies that ...

We report laser spectroscopic and computational studies of host/guest hydration interactions between functional molecules (hosts) and water (guest) in supersonic jets. The examined hosts include dibenzo-18-crown-6-ether (DB18C6), benzo-18-crown-6-ether (B18C6) and calix[4]arene (C4A). The gaseous complexes between the functional molecular hosts and water are generated under jet-cooled condition...

Malignant melanoma is one of the most dangerous forms of cutaneous malignancies [1] . It is classified as cutaneous melanoma and non-cutaneous melanoma based on the location of the lesion. Ultraviolet (UV) radiation exposure is a predisposing factor for cutaneous melanoma, although in other forms such as mucous and anorectal malignant melanomas, ultraviolet radiation does not play a significant...

Deep Swift UV/Optical Telescope (UVOT) imaging of the Chandra Deep Field South is used to measure galaxy number counts in three near ultraviolet (NUV) filters (uvw2: 1928 Å, uvm2: 2246 Å, uvw1: 2600 Å) and the u band (3645 Å). UVOT observations cover the break in the slope of the NUV number counts with greater precision than the number counts by the Hubble Space Telescope (HST) Space Telescope ...

Ultraviolet (UV) fluorescent lamps are widely used in the manufacturing process of biomaterials. The possibility of replacing these lamps with ultraviolet light emitting diodes (UV-LEDs) was investigated and the results are presented here. A number of emission characteristics, including the spectral output and intensity of both light sources were measured and compared. The warm up time of the U...

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...

When an Frecipient Escherichia coli K12 bacterium receives Hfr or F-lac+ DNA from an ultraviolet-irradiated donor, its capacity to promote DNA repair and mutagenesis of ultraviolet-damaged phage X is substantially increased. We call this phenomenon indirect ultraviolet-reactivation, since its features are essentially the same as those of ultraviolet-reactivation; this repair process occurs in p...