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As the minority group frequently at the centre of public fear in the post-9/11 era, Arab Americans’ own sentiment toward, and concerns with, crime, has eluded scholarly attention. This study investigated their fear of crime net of five empirically validated fear of crime theoretical models. Face-to-face interviews with a random sample of Arab and non-Arab households in Metro-Detroit, Michigan indicated that net of all controls, Arab Americans experienced significantly higher levels of fear concerning both general and bias crimes than non-Arab Americans. The greater fear among Arab Americans calls for policy and practice change, and moving from perceiving Arab Americans as a major “source” of fear, to “carriers” of fear who are in need of more attention, care, and assistance. 相似文献
406.
Malcolm Stein IV Chien-Fan Chen Daniel J. Robles Christopher Rhodes Partha P. Mukherjee 《Journal of visualized experiments : JoVE》2016,(108)
Research into new and improved materials to be utilized in lithium-ion batteries (LIB) necessitates an experimental counterpart to any computational analysis. Testing of lithium-ion batteries in an academic setting has taken on several forms, but at the most basic level lies the coin cell construction. In traditional LIB electrode preparation, a multi-phase slurry composed of active material, binder, and conductive additive is cast out onto a substrate. An electrode disc can then be punched from the dried sheet and used in the construction of a coin cell for electrochemical evaluation. Utilization of the potential of the active material in a battery is critically dependent on the microstructure of the electrode, as an appropriate distribution of the primary components are crucial to ensuring optimal electrical conductivity, porosity, and tortuosity, such that electrochemical and transport interaction is optimized. Processing steps ranging from the combination of dry powder, wet mixing, and drying can all critically affect multi-phase interactions that influence the microstructure formation. Electrochemical probing necessitates the construction of electrodes and coin cells with the utmost care and precision. This paper aims at providing a step-by-step guide of non-aqueous electrode processing and coin cell construction for lithium-ion batteries within an academic setting and with emphasis on deciphering the influence of drying and calendaring. 相似文献
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W. C. Black IV E. S. Krafsur 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1986,71(5):673-681
Summary Allelic and genotypic frequencies were sampled from a single age class of the common house fly, Musca domestica L., at five farms on six dates from July 6 to October 12, 1982. Allozymes at six loci were resolved with vertical polyacrylamide gel electrophoresis. No consistent departures from random mating were detected. No consistent linkage disequilibrium was observed. Allele frequencies at the farms changed in independent and unpredictable ways. Gene frequencies at the five farms were initially divergent, converged in midsummer, and then progressively diverged. The divergence occured in mid-August when fly populations were large. Variation in gene frequencies at adjacent farms accounted for a large proportion of the variance in allele frequencies among all farms. These observations are consistent with the hypothesis that allele frequencies in young adult flies reflected the habitat in which they matured as larvae.Journal Paper No. 11718 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa, Project No. 2411 相似文献
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The influence of hyperbaric factors on complex of biochemical and haematological parameters was examined in rats (in vivo) on donor blood samples. It was established, that the sojourn in heliox under the pressure 6.1 MPa and rO2 60 kPa results in activation of lipid peroxidation, alteration of erythrocyte oxygen transport function and the suppression of lipid metabolism. There are no significant alterations of these parameters in the comparative experiment with the pO2 40 kPa. The decompression of donor blood samples from 5.1 MPa to 0.1 MPa during 50 minutes had no significant influence on complex of biochemical, haematological and immunological parameters as compared to control probes. 相似文献
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Intensity of lipid peroxidation and activity of antioxidant protection enzymes in erythrocytes were measured in three experiments with 10-24 days exposure of aquanauts under 4.6 and 5.1 MPa. It is established that there is no pathological intensification of lipid peroxidation when oxygen partial pressure in breathing gas mixture is optimal. This process is under reliable control by modulation of antioxidant enzymes activity. The high sensitivity of these research methods allows using them to determine exposure limitations under high pressure and optimal oxygen concentrations in breathing gas mixture. 相似文献