FLUKA simulation of TEPC response to cosmic radiation.

The aircrew exposure to cosmic radiation can be assessed by calculation with codes validated by measurements. However, the relationship between doses in the free atmosphere, as calculated by the codes and from results of measurements performed within the aircraft, is still unclear. The response of a tissue-equivalent proportional counter (TEPC) has already been simulated successfully by the Monte Carlo transport code FLUKA.

Dosimetric considerations on TEPC fluka-simulation and measurements.

The response of a tissue equivalent proportional counter (TEPC) has been simulated with the Monte Carlo transport code FLUKA. The absorbed dose distribution of lineal energy y has been determined for several monoenergetic photon and neutron sources. The agreement between the calculated results and the measurements carried out with different well-known sources is well demonstrated.

Plant uptake of radionuclides in lysimeter experiments.

The results of seven years lysimeter experiments to determine the uptake of 60Co, 137Cs and 226Ra into agricultural crops (endive, maize, wheat, mustard, sugarbeet, potato, Faba bean, rye grass) are described. The lysimeter consists of twelve monolithic soil profiles (four soil types and three replicates) and is located in Seibersdorf/Austria, a region with a pannonian climate (pronounced differences between hot and semi-arid summers and humid winter conditions, annual mean of precipitation: 517 mm, mean annual temperature: 9.8 degrees C).

Ty1-copia retrotransposon-based S-SAP (sequence-specific amplified polymorphism) for genetic analysis of sweetpotato.

RNaseH-LTR regions of the Ty1-copia retrotransposon were amplified and cloned from the sweetpotato genome using RNaseH gene-specific degenerate primers and restriction site-specific adaptor primers. Ninety clones out of the 240 sequenced were identified with a variable degree of homology to the Ty1-copia RNaseH gene. Three ( Str6, Str85, Str187) of the 90 had characteristic RNaseH-gene, stop codon, polypurine track and putative 3' LTR sequence elements.

An example of abnormal glow curves identification in personnel thermoluminescent dosimetry.

The personal Dosimetry Service Seibersdorf analyses monthly a large number of thermoluminescent dosimeters (TLD). The dosimeters consist of LiF chips, and the readout is carried out with an automated Harshaw 8800 reader system. In some cases, the luminescent glow curves of the routine analysis do not have the expected form as a result of external chemical contamination, hardware problems, poor heat transfer, etc.

Electromagnetic compatibility of electronic implants--review of the literature.

The aim of the article was to provide an overview of published studies regarding the electromagnetic compatibility (EMC) of electronic implants. The available literature was sorted according to combinations of implant types and sources of interference. Several experiments concerning the susceptibility of pacemakers to mobile phones have been performed.

Dose quantities in radiation protection and dosemeter calibration.

Dosimetric concepts and the definition of dose quantities for use in radiation protection were defined by the ICRP and the ICRU. Three types of quantities are of relevance for radiation protection purposes: basic physical quantities, protection quantities, and operational quantities. The physical quantities are universally accepted for the characterisation of radiation fields.

EURADOS trial performance test for photon dosimetry.

Within the framework of the EURADOS Action entitled Harmonisation and Dosimetric Quality Assurance in Individual Monitoring for External Radiation, trial performance tests for whole-body and extremity personal dosemeters were carried out. Photon, beta and neutron dosemeters were considered. This paper summarises the results of the whole-body photon dosemeter test.

A new algorithm for identifying abnormal glow curves in thermoluminescence personal dosimetry.

In this paper an algorithm for the investigation of routine curves in thermoluminescence personal dosimetry is presented. In rare cases, the luminescence glow curves do not exhibit the expected form. They have an abnormal shape as a result of, for example, external contamination, hardware problems, and poor heat transfer.

Does ozone exposure protect from photoinhibition?

Tropospheric ozone and high light intensities are two stress factors that often occur simultaneously under natural conditions. Ozone is well known to form oxygen radicals in the apoplastic water and long lasting photoinhibition can cause photooxidative damage also by formation of several species of oxygen radicals. We were interested whether moderate levels of ozone would be able to modulate the response of leaves to photoinhibitory conditions naturally occurring around noon on a bright day.

Estimating the uptake of traffic-derived NO from N abundance in Norway spruce needles.

The N ratio of nitrogen oxides (NO) emitted from vehicles, measured in the air adjacent to a highway in the Swiss Middle Land, was very high [δN(NO) = +5.7‰]. This high N abundance was used to estimate long-term NO dry deposition into a forest ecosystem by measuring δN in the needles and the soil of potted and autochthonous spruce trees [Picea abies (L.

Investigations on immune parameters in welders.

The aim of the present investigation was to study the effects of welding fumes on the human immune system. Thirty male subjects who had regularly welded and 16 control persons without occupational exposure were examined. Cellular immunity was evaluated by phenotyping of peripheral leucocytes, measurement of mitogenic T cell response and T cell stimulation in a heterologous mixed lymphocyte reaction.

Long-term effective decrease of cesium concentration in foodstuffs after nuclear fallout.

The long-term decrease in activity concentrations in various foodstuffs relevant for the long-term ingestion dose after a nuclear fallout is reviewed. The effective decrease observed in various countries of Central Europe after the Chernobyl accident are compared to the effective decrease observed after the atmospheric nuclear weapons testing. The presentation also includes the short-term decline immediately after fallout and the time course in the first year, which are relevant to the first year ingestion dose.

Ozone exposure : Areas of potential ozone risk for selected tree species in Austria.

Increased tropospheric ozone concentrations cause damage to both human health and the environment. To assess the exposure of forest areas and selected tree species to ozone, it is necessary to calculate the ozone exposure distribution. The present article describes the application of an ozone interpolation model to the calculation of the ozone exposure distribution in combination with forest inventory data.

137Cs-migration in soils and its transfer to roe deer in an Austrian forest stand.

The depth distribution of 137Cs in an Austrian spruce forest stand was investigated in soil profiles sampled in thin layers (2 cm) and in pooled soil samples over an area of 200 ha. The 137Cs concentrations both from Chernobyl and global fallout decrease exponentially with depth. Forty-six percent of Chernobyl-derived caesium and 26% from global fallout are still to be found in the litter layer; <3% (for global fallout 6%) have reached layers deeper than 20 cm of mineral soil.

Present knowledge about specific absorption rates inside a human body exposed to radiofrequency electromagnetic fields.

We have compiled results of scientific investigations about the relationship between external field-strengths and specific absorption rates inside the human body. The data were normalized to SAR-values that form the basis for current safety standards. Results were compared to exposure limits given in these standards.

Longterm reduction of caesium concentration in milk after nuclear fallout.

Time trends in activity concentrations in milk as observed in Austria after the Chernobyl accident are presented. Both the short term decrease immediately after fallout and the medium term decline in the years following the event are very important for estimating the total exposure to be expected from a given deposition. In order to avoid artifacts due to local fallout, plant variations, or differences in the metabolism of single animals, large areas of production were used for the observations.

Occupational exposure and its effect on some immune parameters.

Some immunological parameters were investigated in a group of workers exposed to external radiation (1.4 to 9.8 mSv) and inhalation of tritium (comm.

Remediation of groundwater polluted with chlorinated ethylenes by ozone-electron beam irradiation treatment.

OH radicals formed in water radiolysis may be effectively used for the oxidative decomposition of trichloroethylene and perchloroethylene contained as micropollutants in groundwater. Addition of ozone to the water before irradiation causes the reducing species of the water radiolysis to be converted into OH radicals. Moreover, this eliminates the dose rate effect observed with irradiation alone.

Estimate of the dose due to 90Sr to the Austrian population after the Chernobyl accident.

In order to estimate the contribution of 90Sr to the exposure of the Austrian population, the ratio of 90Sr to 137Cs in 126 food samples and nine drinking water samples was determined. From this and the average activity concentration of 137Cs in each type of food as obtained by the measurement of some 100,000 food samples after the Chernobyl accident, a good estimate of the average activity concentration of 90Sr in these food items could be obtained. Samples were investigated at various times after the accident to take into account possible changes with time in the 90Sr-activity concentration and its ratio to 137Cs.

Radiation-induced decomposition of small amounts of trichloroethylene in drinking water.

Solutions of 10 ppm trichloroethylene in air-saturated drinking waters are decomposed by gamma radiation with initial G-values, G0, around 3-5 molecules per 100 eV. At lower concentrations, the G0-values decrease with decreasing trichloroethylene concentration and with increasing amounts of inorganic (especially HCO3- and NO3-) and organic solutes. From the results, a semi-empirical formula is derived which allows an estimation of G0-values for the trichloroethylene decomposition in drinking waters of given composition.

Mutagenicity of chlorinated polycyclic aromatic compounds.

The catalytic chlorination of polycyclic aromatic hydrocarbons leads to the formation of complex mixtures of isomers analogous to those found in fly ash samples of an incineration plant for radioactive waste. Therefore chlorination mixtures of chrysene, pyrene, and fluoranthene were analyzed and characterized by gas chromatography-mass spectrometry. Determination of the exact position of each chlorosubstituent within the molecule was not possible either by mass spectrometry or by comparison with well-defined methyl analogs.