ultraviolet radiation (uvr) has been accepted as an attractive alternative to chlorination for the disinfection of wastewater. in this study the effluent from sahebgaranieh treatment plant was subjected to changes in uv transmission and turbidity in order to correlate these commonly measured parameters with the performance of a submerged -uv- reactor employed in disinfecting the effluent. studi...

Two groups of 30 dorsally shaved opossums (Monodelphis domestica) were exposed three times per week for 81 weeks to 250 J/m2 of UV radiation from FS40 sunlamps (approximately 150 J/m2 of UV radiation B; UV-B), or to 2.5 x 10(4) J/m2 of UV radiation A (UV-A) from filtered F40BLB fluorescent lamps (black lights). Animals were monitored for the appearance of nonmelanoma skin tumors (NMSTs) and mel...

Outdoor workers who occupationally spend large periods of time exposed to ultraviolet irradiance are at increased risk of developing certain types of non-melanoma skin cancer in addition to being prone to erythema and eye damage. UV exposure to workers is affected by a number of factors including geographic location, season, individual biological factors and the local surroundings. Urban enviro...

OBJECTIVES Ultraviolet (UV) light-mediated photofunctionalisation is known to improve osseointegration of pure titanium (Ti). However, histological examination of titanium alloy (Ti6Al4V), which is frequently applied in orthopaedic and dental surgery, has not yet been performed. This study examined the osseointegration of photofunctionalised Ti6Al4V implants. METHODS Ti and Ti6Al4V implants w...

A new method for autoradiographic measurement of unscheduled DNA synthesis (UDS) in the skin in vivo after treatment with ultraviolet light (UV) was developed. The skin of the back of ICR mice was shaved and exposed to short-wave UV (254 nm) or UVAB (sunlamp, 270 to 440 nm, predominant emission at 312 nm) at various doses. Immediately after irradiation, an isotonic aqueous solution of [methyl-3...

This paper presents a harmonic+noise speech coder which uses an efficient spectral quantization technique and a novel voiced/unvoiced (V/UV) mixing model. The harmonic magnitudes are coded at 23 bits/frame using the magnitude response of a linear predictive coding (LPC) system. The difference between the harmonic magnitudes and the sampled magnitude response is minimized by the closed-loop appr...

Ultraviolet (UV) radiation—especially UV-B radiation—can have detrimental effects on marine larvae and elicit behavioral changes in many adult marine organisms. Although there has been a considerable amount of research on chromatophores in marine organisms, little is known about the relationship between cephalopod chromatophores and exposure to UV-B radiation. This study investigates the effect...

Ultraviolet-B radiation (UV-B; 280–320 nm) penetrates some aquatic habitats to biologically significant depths and can alter life histories of aquatic organisms, including algae, zooplankton, fish, and amphibians. Although major species differences have been documented for UV-B sensitivity, few studies have examined differences between populations of the same species. Previous work has suggeste...

Adenovirus is a focus of the water treatment community because of its resistance to standard, monochromatic low-pressure (LP) UV irradiation. Recent research has shown that polychromatic, medium-pressure (MP) UV sources are more effective than LP UV for disinfection of adenovirus when viral inactivation is measured using cell culture infectivity assays; however, UV-induced DNA damage may be rep...

This paper describes the experiments carried out to analyse total dissolved N involving UV oxidation and high temperature catalytic oxidation (HTCO) methods. Standards of known N concentrations (i.e. ammonium and EDTA) irradiated with UV oxidation for 6 h were found to show good oxidation efficiency (72-107%). However, poor recovery was recorded for urea (2-20%). The addition of reaction initia...