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41.
Combined meta-analysis with structural equations modeling (SEM) to validate the W. H. Mobley et al (1978) turnover theory as well as alternative structural networks proposed by A. Dalessio et al (1986), P. W. Hom et al (1984), and B. D. Bannister and R. W. Griffeth (1986). The authors aggregated correlations from 17 studies (N?=?5,013 employees), correcting for unreliability and sampling error. Then they used SEM to assess the models, comparing their relative fits to data. SEM analyses corroborated the Mobley et al model better than did past research, but these analyses also showed that the Dalessio et al and the Hom et al theories explained sample data more plausibly. Additional SEM tests found that turnover base rates, time lags between turnover and model assessments, unemployment rates, and occupational differences moderated the models' pathways. The present findings suggest various implications for these theories and for turnover research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
42.
Psychological tests developed in the United States are being widely adapted into other languages and cultures around the world. This article examines the generalizability and utility of personality assessment instruments across cultures and addresses methodological issues related to using personality questionnaires in countries different from the one in which they were developed. This article specifically highlights the application of objective psychological tests in Asia with special emphasis on the most widely used and internationally adapted personality instrument, the Minnesota Multiphasic Personality Inventory-2 (MMPI-2). Effective strategies for translating, adapting, and standardizing questionnaires in languages and cultures different from their country of origin are reviewed. The history of several successful adaptations of the original MMPI and MMPI-2 is surveyed to illustrate the extensive research base for the test in Asia. Current research is summarized, and recommendations for future research are provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Male goats (“Criolla Argentina” breed), castrated at 45 days of age, showed altered lipid metabolism 180 days after castration as compared to control goats. Subcutaneous, perirenal and omental adipose tissues of castrated goats showed increases in fatty acid synthetase, glucose-6-phosphate dehydrogenase and NADP-isocitrate dehydrogenase activities. Castration increased the amount of total lipids and triglycerides, but did not modify the amount of cholesterol, phospholipid and protein in the three types of adipose tissue. The incorporation of [1-14C]acetate into fatty acids of subcutaneous and perirenal adipose tissue was increased in castrated goats in relation to noncastrated goats. Our results suggest that removal of gonadal steroids increases significantly the rate of lipogenesis in adipose tissue of male goats.  相似文献   
44.
NMR study of the phosphonomethylation reaction on chitosan   总被引:1,自引:0,他引:1  
N-Phosphonomethylation of chitosan reaction was studied and optimized using different reaction conditions. NMR spectroscopy was an important tool in this work to study this reaction and the α-aminomethylphosphonic acid function introduced onto chitosan was unequivocally characterized by 31P and 13C NMR analyses. But surprisingly, whatever the reaction conditions used, N-phosphonomethylation reaction of chitosan cannot be dissociated from a side reaction: the N-methylation reaction of chitosan. A mechanism was proposed to explain the formation of this side product.  相似文献   
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The identification of various isoforms of olfactory binding proteins is of major importance to elucidate their involvement in detection of pheromones and other odors. Here, we report the characterization of the phosphorylation of OBP (odorant binding protein) and Von Ebner’s gland protein (VEG) from the pig, Sus scrofa. After labeling with specific antibodies raised against the three types of phosphorylation (Ser, Thr, Tyr), the phosphate-modified residues were mapped by using the beta-elimination followed by Michael addition of dithiothreitol (BEMAD) method. Eleven phosphorylation sites were localized in the pOBP sequence and nine sites in the VEG sequence. OBPs are secreted by Bowman’s gland cells in the extracellular mucus lining the nasal cavity. After tracking the secretion pathway in the rough endoplasmic reticulum of these cells, we hypothesize that these proteins may be phosphorylated by ectokinases that remain to be characterized. The existence of such a regulatory mechanism theoretically increases the number of OBP variants, and it suggests a more specific role for OBPs in odorant coding than the one of odorant solubilizer and transporter. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Chrystelle Le Danvic and Fanny Brimau contributed equally to the work.  相似文献   
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The failure mechanisms of a NiAlPt/electron beam physical vapor deposition yttria-stabilized-zirconia thermal barrier coating system deposited on the AM1 single crystalline substrate have been investigated under pure creep conditions in the temperature range from 1273 K to 1373 K (1000 °C to 1100 °C) and for durations up to 1000 hours. Doubly tapered specimens were used allowing for the analysis of different stress states and different accumulated viscoplastic strains for a given creep condition. Under such experiments, two kinds of damage mechanisms were observed. Under low applied stress conditions (i.e., long creep tests), microcracking is localized in the vicinity of the thermally grown oxide (TGO). Under high applied stress conditions, an unconventional failure mechanism at the substrate/bond coat interface is observed because of large creep strains and fast creep deformation, hence leading to a limited TGO growth. This unconventional failure mechanism is observed although the interfacial bond coat/top coat TGO thickening is accelerated by the mechanical applied stress beyond a given stress threshold.  相似文献   
49.
The patterning of conductive substrates by polymer brushes may be achieved by using successively scanning electrochemical microscopy (SECM) and atom transfer radical polymerization (ATRP). After the surface functionalization by a brominated aryldiazonium initiator, SECM allows the local reduction at the micrometer scale of the initiator grafted layer. Different channels sizes involved in charge transport within the initiator layers are evidenced by combining SECM, CV and observation of the aryl-grafted layer transformation. ATRP is performed on the SECM patterned substrate. Inside the pattern, the lower density of initiator decreases the polymer thickness. The pattern resolution is enhanced when the direct mode of the SECM is used instead of the mediated indirect mode.  相似文献   
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