Considering the issues involved in industrial cutting and machining systems, and, in particular, the problems arising from the use of cutting fluids in these systems, this study presents the results of an analysis that points to a safe and efficient way to reduce contaminated microbial cutting fluids using ultraviolet radiation. The study proposes a transmitter system of simple ultraviolet radi...

REVIOUS workers have found that in maize the genetic analyses have indicated P an apparent difference between the action of X-ray and ultraviolet on (1) gene mutation, (2) the frequency of reciprocal translocations, (3) the type and frequency of endosperm deficiencies, (4) the ratio of endosperm deficiencies to embryo abortions, and ( 5 ) the types of embryo deficiencies. These contrasts have b...

The mechanism by which ultraviolet radiation induces melanogenesis in epidermal melanocytes is unknown. Previous observations that in cultured human melanocytes 1-oleoyl-2-acetylglycerol augmented both basal and ultraviolet radiation-induced melanogenesis, suggested that the responses were mediated via protein kinase C. However, paradoxically the phorbol ester TPA was without effect. Therefore,...

Purpose: The objective of the present study was to evaluate the effect of ultraviolet ray combined with immersion method on the disinfection of silicone impression materials. Methods: Forty eight silicone impressions were rinsed by flushing water and then completely dried. Impressions were randomly divided into A and B groups (n=24). In group A, serum sample with positive hepatitis B virus was ...

This study examines the effects of ecologically important levels of ultraviolet B radiation on protein D1 turnover and stability and lateral redistribution of photosystem II. It is shown that ultraviolet B light supported only limited synthesis of protein D1, one of the most important components of photosystem II, whereas it promoted significant degradation of proteins D1 and D2. Furthermore, d...

A considerable interest is growing worldwide about the photobiological effects of the ultraviolet radiation; in fact, it has been demonstrated that ultraviolet radiation can affect both human health as well as the equilibrium of entire ecosystems. The relative effectiveness of ultraviolet radiation at a particular wavelength in producing a specific biological response is defined by an action sp...

Ultraviolet-B (UV-B) stress appears to be more striking than other research works because of the thin ozone layer. The protective influence of an exogenous nitric oxide donor and sodium nitroprusside (SNP) on the growth properties of Larix gmelinii seedlings was investigated under ultraviolet-B radiation conditions. The results indicated that 0.1 mM SNP could effectively alleviate the damage ca...

The projected large increases in damaging ultraviolet radiation as a result of global emissions of ozonedepleting substances have been forestalled by the success of the Montreal Protocol. New challenges are now arising in relation to climate change. We highlight the complex interactions between the drivers of climate change and those of stratospheric ozone depletion, and the positive and negati...

Introduction. Azithromycin is among the broad-spectrum antibiotics that is widely available in various environmental systems and could have destructive effects on the ecosystem and human health due to its bacterial resistance. In this study, removal of azithromycin from wastewater using an advanced oxidation process of ultraviolet light with and without persulfate was investigated and effective...

A new dosimetric package for assessing solar radiation affecting photosynthesis in the visible and ultraviolet wavebands in plant canopies has been developed and tested. The package consists of several detectors sensitive to various wavebands between 290 and 700 nm. For photosynthetically active radiation (PAR), the dosimeter was calibrated for exposures in terms of photosynthetically active ph...