Ultraviolet light (u.v.) irradiation of the vegetal hemisphere of Xenopus laevis eggs resulted in the elimination of primordial germ cells in tadpoles. Quantitative studies were performed on this phenomenon. The stage sensitivity to u.v. inactivation of germ cell formation was obtained for the early developmental stages ranging from immediately after fertilization to small-cell blastula. It was...

Kelner (1949a) first reported that mutations to phage resistance induced in Escherichia coli by ultraviolet light could be reversed by immediate irradiation with white light. In addition he noted that end-point mutations in contrast to zero-point mutations were not reversed by visible light (1949b). At the same time Novick and Szilard (1949) reported that light-reactivation of E. coli reduced t...

With the widespread of novel coronavirus (SARS-CoV-2), inactivation bacteria and viruses using ultraviolet (UV) light has been reevaluated. However, there are many applications where safety to human body itself effect questioned, is a movement review UV-C guidelines (Global Lighting Association, Position Statement on Germicidal Irradiation SAFETY GUIDELINES, 2020). Since Minamata Convention Mer...

background the treatment of onychomycosis is a challenge and infections are typically more severe and difficult to treat in toenails than in fingernails. objectives the current study aimed to investigate the fungicidal effect of ultraviolet radiation on the growth of dermatophytes isolated from nails. patients and methods samples from patients with clinical manifestations of onychomycosis were ...

Introduction: Cutaneous leishmaniasis is a mutual parasitic disease, which is endemic in some countries of the world. The use of common drugs has been restricted because of confirmed side effects and drug resistance. There are still serious challenges in the treatment of CL. Developing new therapeutic methods for leishmaniasis, besides obtaining a prompt treatment response that...

PURPOSE To evaluate the thinnest corneal thickness changes during and after corneal collagen cross-linking treatment with ultraviolet-A irradiation, using hypo-osmolar riboflavin solution in thin corneas. METHODS Eighteen eyes of 18 patients were included in this study. After epithelium removal, iso-osmolar 0.1% riboflavin solution was instilled to the cornea every 3 minutes for 30 minutes. H...

The analysis of the ultraviolet induced transformation thermal decomposition spectra monomer submicrometer layers polymethylmethacrylate and its composite with fullerene C 60 for different concentrations irradiation doses has been carried out. Formation new stages in interpreted by binding between side ester groups polymethylmethacrylate. Keywords: polymethylmethacrylate, fullerene, irradiation...

the degradation of poly (vinyl pyrrolidone) (pvp) by means of ultrasound irradiation and itscombination with heterogenous photocatalysis (tio2 nanoparticles) was investigated. emphasiswas given on the effect of additive on degradation rate constants. 24 khz of ultrasoundirradiation was provided by a sonicator, while an ultraviolet source of 30 w was used for uvirradiation. to increase the effic...

In contrast to ultraviolet and infrared irradiation, which are known to facilitate cutaneous photoaging, immunosuppression, or tumour emergence due to formation of free radicals and reactive oxygen species, potentially similar effects of visible light on the human skin are still poorly characterized. Using a blue-violet light irradiation source and aiming to characterize its potential influence...

Seventy mucoid mutants retaining the phenotypic properties of the ultraviolet-induced lon strains of Escherichia coli K-12 were isolated after treatment of strain MQ259 (lon+) with ozone. They produce mucoid colonies at 37 C on minimal agar, are abnormally sensitive to radiation, and tend to grow in long aseptate filaments after irradiation with ultraviolet light. Results indicate also that ozo...