Search results for "RADIATION"
showing 10 items of 5298 documents
UV-induced cross-linking of proteins to plasmid pBR322 containing 8-azidoadenine 2′-deoxyribonucleotides
1988
Abstract An efficient method of cross-linking DNA to protein is described. The method is based on the incorporation of photoactive 8-azidoadenine 2′-deoxyribonucleotides into DNA. We have found that 8-N 3 dATP is a substrate for E. coli DNA polymerase I and that 8-N 3 dATP can be incorporated into plasmid pBR322 by nick-translation. Subsequently we were able to cross-link a set of different proteins to 8-azido-2′-deoxyadenosine-containing pBR322 by UV irradiation (366 nm). No DNA-protein photocross-linking was observed under the same conditions when the non-photoactive plasmid pBR322 was used.
Growth and defense in deciduous trees and shrubs under UV-B
2005
Abstract Reflection by waxy or resinous surface structures and hairs, repair reactions of biomolecules and induction of different sheltering components provide the means of plant protection from harmful solar UV-B radiation. Secondary products, especially flavonoids and phenolic acids as defense components are also important in plant tolerance to UV-B, fulfilling the dual role as screens that reduce UV-B penetration in plant tissues, and as antioxidants protecting from damage by reactive oxidant species. Plants are sensitive to UV-B radiation, and this sensitivity can be even more clone-specific than species-specific. The results available in the literature for deciduous trees and shrubs in…
Exposure to increased ambient ultraviolet B radiation has negative effects on growth, condition and immune function of juvenile Atlantic salmon (Salm…
2008
Atlantic salmon (Salmo salar) parr were exposed in two outdoor experiments, ranging in duration from 52 to 137 days, to spectral treatments: (1) natural sunlight (=present ambient UVB level), (2) solar radiation supplemented with enhanced UVB radiation from lamps simulating 20% or 8% stratospheric ozone loss or (3) UVB-depleted sunlight achieved by screening with Mylar-D film. The growth, condition and immune function of the salmon were quantified after treatments. Exposure to enhanced UVB radiation retarded growth, and decreased hematocrit value and plasma protein concentration. Further, enhanced UVB radiation affected plasma immunoglobulin concentration. The results demonstrate that juven…
Influence of double infections on the induction of thymidine kinase by UV-irradiated herpes simplex virus types 1 and 2 and pseudorabies virus
1975
Simultaneous infection of primary rabbit kidney cells with HSV type 1 TK+ and a TK- strain results in a mutual influence of both viruses on the induction of thymidine kinase (TK). TK+ virus has an enhancing and TK- virus a depressing effect on TK induction by a superinfecting TK+ virus. The enzyme induction depends on the ratio of multiplicities of both viruses. The mutual influence on TK induction depends further on the time of addition of the superinfecting virus: the effect of the second virus can still be observed when given 6 hours after primary infection. Identical phenomena can be observed using combinations with HSV type 2 or Pseudorabies viruses. The ability of HSV to induce TK is …
Aerosol radiative forcing efficiency in the UV region over southeastern Mediterranean: VELETA2002 campaign
2007
Atmospheric aerosol effects on spectral global UV irradiance were evaluated during the VELETA2002 field campaign between 8 and 19 July 2002 in southeast Spain. In the first stage, seven UV spectroradiometer and six CIMEL Sun photometer measurements were carried out simultaneously, allowing them to be calibrated and intercompared. The mean ratio obtained for the global irradiance between the spectroradiometers, with regards to a reference instrument, ranges from 0.98 up to 1.04 with standard deviations that oscillate between ±0.01 and ±0.17. In particular, the two spectroradiometers used to obtain the aerosol forcing efficiencies have a ratio of 1.000 ± 0.001. The aerosol optical depth (AOD)…
Protective effect of trehalose-loaded liposomes against UVB-induced photodamage in human keratinocytes
2014
Trehalose, a naturally occurring non-reducing disaccharide, is known to act as a major protein stabilizer that can reduce ultraviolet B (UVB)-induced corneal damage when topically applied to the eye. However, due to the low skin permeability of trehalose, which makes the development of topical formulations difficult, its use as a skin photoprotective agent has been limited. Previous findings demonstrated that liposomes may significantly improve the intracellular delivery of trehalose. Therefore, the present study aimed to assess the protective effects of trehalose-loaded liposomes against UVB-induced photodamage using the immortalized human keratinocyte cell line, HaCaT. The effects were al…
Status of new 18 GHz ECRIS HIISI
2018
A new 18 GHz ECR ion source HIISI is under commissioning at the Accelerator Laboratory at the University of Jyvaskyla (JYFL). The main purpose of HIISI is to produce high-energy beam cocktails, e.g. Xe44+, for radiation effects testing of electronics with the K130 cyclotron. The initial commissioning results in 18+14 GHz operation with oxygen, argon and xenon are reported. The beam currents are compared to those produced by reference ion sources (JYFL 14 GHz ECRIS, GTS and SuSI). At the moment (October 2017) 560 µA of O6+ and 310 µA of Ar13+, for example, have been reached with HIISI at 2.3 kW total power.A new 18 GHz ECR ion source HIISI is under commissioning at the Accelerator Laboratory…
Determination of extremely low (236)U/(238)U isotope ratios in environmental samples by sector-field inductively coupled plasma mass spectrometry usi…
2005
A method by inductively coupled plasma mass spectrometry (ICP-MS) was developed which allows the measurement of (236)U at concentration ranges down to 3 x 10(-14)g g(-1) and extremely low (236)U/(238)U isotope ratios in soil samples of 10(-7). By using the high-efficiency solution introduction system APEX in connection with a sector-field ICP-MS a sensitivity of more than 5,000 counts fg(-1) uranium was achieved. The use of an aerosol desolvating unit reduced the formation rate of uranium hydride ions UH(+)/U(+) down to a level of 10(-6). An abundance sensitivity of 3 x 10(-7) was observed for (236)U/(238)U isotope ratio measurements at mass resolution 4000. The detection limit for (236)U a…
Use of Dual-Energy Computed Tomography for Evaluation of Genitourinary Diseases
2018
Since its clinical inception a decade ago, dual-energy computed tomography has expanded the array of computed tomography imaging tools available to the practicing abdominal radiologist. Of note, diagnostic solutions for imaging-based evaluation of genitourinary diseases, foremost kidney calculi and renal tumors characterization, represent the apogee applications of dual-energy computed tomography in abdominal imaging. This article reviews clinical applications of dual-energy computed tomography for the assessment of genitourinary diseases.
Specific UV and VUV spectra light sources
1997
The report contains information about laboratory made radiofrequency powered electrodeless discharge sources (lamps) of resonance atomic spectra radiation for various elements (e.g. Hg, Cd, Zn, O, S, Se, Te, As, Sb, Bi, J, Br, Kr, Xe, H) having main spectral lines in UV and VUV region. There are known, and can be found a lot of new specific applications of such sources in laboratory made or commercial optical devices.