The hereditary dysplastic nevus syndrome (DNS) is a well-characterized disorder in which affected individuals have increased numbers of premalignant (dysplastic) nevi and a markedly increased risk of developing cutaneous melanoma. Seeking evidence of a systemic disorder in DNS, we examined the effect of ultraviolet radiation on cultured lymphoid cells. Epstein-Barr virus-transformed lymphoblast...

The effect of R plasmids on spontaneous and radiation (ultraviolet and gamma)-induced mutability in Pseudomonas aeruginosa was studied in strains containing the radiation-sensitive markers polA3 or rec-2 and the revertable auxotrophic markers hisO27 and trpB1. In the absence of an R plasmid, the radiation-induced mutability was dependent on the recA+ genotype and independent of the polA+ genoty...

In this work Eucalyptus grandis and Dipteryx odorata were submitted to photodegradation by ultraviolet radiation. The effect of ultraviolet radiation irradiation on the color change and chemical composition of each wood flour were evaluated. The samples were submitted to a total of 500h of artificial weathering using condensation stages and ultraviolet radiation B irradiation cycles. The change...

In the study of the bactericidal action of ultraviolet radiation on air-borne organisms, it is difficult to determine the number of bacteria per unit volume floating in the air and to measure the lethal radiation to which the organisms were exposed. In studying this action, Fair and Wells (1935) atomized a water suspension of Escherichia coli into a room and measured the normal rate at which th...

Kurtin, Bierman and Yontef (1) reported on the prevention of ultraviolet erythema by iontophoresis of a solution of Pyribenzamine (N -pyridyl-N -benzyl-N -dimethylethylene diamine hydrochloride) into the skin prior to exposure to a hot quartz ultraviolet lamp. They attributed this effect to the "antihistaminic "action of Pyribenzamine in the tissues. We were able to confirm the findings of Kurt...

A growth-chamber experiment was conducted to evaluate whether ethylenenediurea (EDU), a chemical shown to be protective against ozone pollution, could ameliorate foliar damage induced by ultraviolet-B (UV-B) radiation exposure in 'Roanoke' soybean (Glycine max L.), a UV-B-sensitive cultivar, and whether these effects could be discriminated using fluorescence (F) observations. The experiment had...

We show that a liquid-hydrogen droplet can achieve high- Q values that exceed 10(9) for whispering-gallery modes in the ultraviolet. We show also that pumping high- Q liquid-hydrogen droplets with ultraviolet laser radiation generates many vibrational and rotational Raman sidebands that cover a broad spectral range from the ultraviolet to the near infrared.