The purification and properties of an ultraviolet (UV) repair endonuclease are described. The enzyme is induced by infection of cells of Escherichia coli with phage T4 and is missing from extracts of cells infected with the UV-sensitive and excision-defective mutant T4V(1). The enzyme attacks UV-irradiated deoxyribonucleic acid (DNA) containing either hydroxymethylcytosine or cytosine, but does...

We present a facile synthesis of manganese oxide (MnO(2)) nanocomposite with ultraviolet (UV) photosensitive characteristic by a solid-state reaction based on the reduction of potassium permanganate (KMnO(4)) by aniline, which provides a new family and more selectivity for UV photosensitive nanomaterials in the future.

Defects in the bacterial recB or recC or phage red or int gene did not impair ultraviolet light-induced clear mutations of lambda phage. Clear mutants of cI and cII genes were not enriched among RecA-promoted UV-induced recombinants between the N and O genes which closely encompass the c genes. No correlation was observed between UV-induced mutation and genetic recombination.

Enhancement of photoluminescence (PL) signal from Gd-doped silica glass densified by rapid thermal treatment (RTT) in the ultraviolet (UV) is investigated. Significant decrease of the loss covering the UV band is observed. The strong emission detected at 314 nm is assigned to the P7/2 to S7/2 transition under excitation of DJ, IJ, and PJ energy levels of the Gd.

Far-UV observations in and near the Hubble Deep Fields demonstrate that the Space Telescope Imaging Spectrograph (STIS) can potentially obtain unique and precise measurements of the diffuse far-ultraviolet background. Although STIS is not the ideal instrument for such measurements, high-resolution images allow Galactic and extragalactic objects to be masked to very faint magnitudes, thus ensuri...

Deep-ultraviolet surface-enhanced Raman scattering (UV-SERS) is a promising technique for bioimaging and detection because many biological molecules possess UV absorption lines leading to strongly resonant Raman scattering. Here, Al nanovoid substrates are developed by combining nanoimprint lithography of etched polymer/silica opal films with electron beam evaporation, to give a high-performanc...

Some ultraviolet light (UV)-induced fibrosarcomas produce more experimental pulmonary tumor colonies in UV-irradiated hosts than in normal syngeneic recipients. The number of experimental metastases produced following i.v. injection of these tumors increases in proportion to the dose of UV radiation. This enhancement can be transferred with lymphoid cells to lethally X-irradiated recipients and...

Cataractous and noncataractous human lenses were irradiated with ultraviolet (UV) light, and the resulting triplet and radical species were studied by electron paramagnetic resonance spectroscopy. Evidence is presented that free radicals are produced by a biphotonic process involving tryptophan as an intermediate triplet. This makes free radical production energetically feasible. A possible lin...

Rat mouse, and chick lenses incubated with 3-aminotriazole under long-wave ultraviolet (UV) show reduced accumulation and incorporation of leucine and a loss of glutathione. The effect on leucine incorporation is strikingly enhanced when capsule-epithelium pools are incubated. The procedure may identify photosensitizers or metabolic inhibitors which are cataractogenic when acting in conjunction...