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The ENTOREL Database for radiation stressed electronic components and systems has been established to collate data on high doses (aiming at Mega Grays) which meet the requirements of advanced teleoperators working in hazardous or disordered nuclear environments within the frame of a European telerobotics programme for the nuclear industry. The ENTOREL Database holds data from 614 tests on total dose effects 相似文献
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This article presents a longitudinal study of employment, unemployment and health of migrant workers in Germany. The analyses were conducted with longitudinal samples of the waves 1-6 (1984-1989) and the waves 6-9 (1989-1992) of the German Socio-Economic Panel (GSOEP). German and migrant workers did not respect to their health satisfaction but unemployed foreign workers were quite less satisfied with their health than unemployed Germans. This corresponded with a high percentage of foreign unemployed (30-50%) who felt chronically ill. A further examination of two (dichotomously formulated) principal investigation hypotheses could not show that the data support the explanation that the poorer health of unemployed migrants was caused by the unemployment situation. The results are interpreted in the way that the unemployed migrants' poorer health can be explained with (health) selection processes in the labour market. 相似文献
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John Seifert Angela Frelich Linda Shecterle John St Cyr 《Journal of the International Society of Sports Nutrition》2008,5(1):1-5
D-ribose, a naturally occurring pentose carbohydrate, has been shown to replenish high- energy phosphates following myocardial ischemia and high intensity, repetitive exercise. Human studies have mainly involved short-term assessment, including potential toxicity. Reports describing adverse effects of D-ribose with prolonged ingestion have been lacking. Therefore, this study assessed the toxicity of extended consumption of D-ribose in healthy adults. Nineteen subjects ingested 20 grams/Day (10 grams, twice a Day) of ribose with serial measurements of biochemical and hematological parameters at Days 0, 7, and 14. No significant toxic changes over the 14-day assessment period occurred in complete blood count, albumin, alkaline phosphatase, gamma glutamyltransferase, alanine amiotransferase, and aspartate aminotransferase. However, D-ribose did produce an asymptomatic, mild hypoglycemia of short duration. Uric acid levels increased at Day 7, but decreased to baseline values by Day 14. D-ribose consumption for 14 days appears not to produce significant toxic changes in both hematological and biochemical parameters in healthy human volunteers. 相似文献
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Tobias Unruh Jürgen Neuhaus Winfried Petry 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2007,580(3):1414-1422
The TOFTOF spectrometer is a multi-disc chopper time-of-flight spectrometer for cold neutrons at the research neutron source Heinz Maier-Leibnitz (FRM II). After five reactor cycles of routine operation the characteristics of the instrument are reported in this article. The spectrometer features an excellent signal to background ratio due to its remote position in the neutron guide hall, an elaborated shielding concept and an s-shaped curved primary neutron guide which acts i.a. as a neutron velocity filter. The spectrometer is fed with neutrons from the undermoderated cold neutron source of the FRM II leading to a total neutron flux of 1010n/cm2/s in the continuous white beam at the sample position distributed over a continuous and particularly broad wavelength spectrum. A high energy resolution is achieved by the use of high speed chopper discs made of carbon-fiber-reinforced plastic. In the combination of intensity, resolution and signal to background ratio the spectrometer offers new scientific prospects in the fields of inelastic and quasielastic neutron scattering. 相似文献
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A Blume K Seifert CJ Lebrun E M?llenhoff P Gass T Unger T Herdegen 《Canadian Metallurgical Quarterly》1998,241(2-3):87-90
Binding to olfactory receptors is the first step in odorant and pheromonal recognition and discrimination. These receptors constitute one of the most important, although poorly known, families of neuronal receptors. In this study we used degenerated oligonucleotides and a RT-PCR approach to selectively amplify olfactory receptors in the nasal epithelium of the domestic pig Sus scrofa. Several combinations of oligonucleotide were tested and allowed the isolation of eleven different partial sequences belonging to the seven transmembrane olfactory receptor family. These receptors formed a separate family within the seven transmembrane receptor superfamily in pigs. Using the criteria of Ben Arie et al. [Ben-Arie N., Lancet D., Taylor C., Khen M., Walker N., Ledbetter DH., Carrozzo R., Patel K., Sheer D., Lehrah H. and North M., Hum. Mol. Genet., 3 (1994) 229-235], the 11 receptors described here can be classified into three known families and seven subfamilies (one known and six new). 相似文献
9.
In the present investigation it has been shown exemplarily for an austenite microstructure containing carbonitrides that the specific restraining force of a grain boundary due to the distribution of precipitates can be described by a modified Orowan's law, so that the grain boundary movement is considered to be analogous to the dislocation movement. This is achieved by using a modified restraining force Fr (corresponding to the cubic geometry of the particles), a detailed thermodynamic analysis of the precipitates (in this case, carbonitrides) and selected relation for the interparticle spacing La. The specific restraining force and the interparticle spacing depend on temperature within the austenite range. Each temperature is attached to a couple (Fr/La). The plot Fr against shows straight lines for each steel and from their average slope, a shear module G' of grain boundaries, which is about 64300 N·cm?2, is obtained. Hence, it is possible to describe the specific restraining force of a grain boundary with the help of Orowan's law or as it is conventionally done by using Zener's modell. At a critical temperature T*, which is different for each steel, the specific restraining force is equal to the driving force of the grain boundary. The corresponding values of La are also different for each steel and the steel which is the most resistant to grain coarsening is allowed to have the greatest value of La which still retains the capacity of impeding grain coarsening. 相似文献
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