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We constructed a simple STR pentaplex of new loci recommended as next generation markers for the European Standard Set (ESS) comprising normal-amplicon STRs: D12S391 and D1S1656, plus mini-amplicon STRs: D2S441, D10S1248 and D22S1045. Validation of the pentaplex included evaluation of its ability to amplify DNA from a variety of degraded forensic casework samples. Although the ESS-pentaplex was designed in the first instance to generate allele frequency data to supplement existing databases of established STRs, the multiplex proved to be a valuable tool for the analysis of challenging DNA when certain markers of Identifiler or MiniFiler occasionally failed.  相似文献   
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The last three decades have witnessed the spread of employee empowerment practices throughout the public and private sectors. A growing body of evidence suggests that employee empowerment can be used to improve job satisfaction, organizational commitment, innovativeness, and performance. Nearly all previous empirical studies have analyzed the direct effects of employee empowerment on these outcome variables without taking into account the mediating role of employee attitudes. This article contributes to the growing literature on employee empowerment by proposing and testing a causal model that estimates the direct effect of employee empowerment on performance as well as its indirect effects as mediated by job satisfaction and innovativeness. The empirical analysis relies on three years of data from the Federal Human Capital Survey/Federal Employee Viewpoint Survey and a structural equation modeling approach, including the use of lagged variables. The results support the hypothesized causal structure. Employee empowerment seems to have a direct effect on performance and indirect effects through its influence on job satisfaction and innovativeness, two key causal pathways by which empowerment practices influence behavioral outcomes.  相似文献   
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The U.S. Congress created the Small Disadvantaged Business (SDB) and Women‐Owned Small Business (WOSB) programs to promote fairness in government contracting. In this article, the authors examine whether increases in racial and gender representation in federal agencies correlate with the proportion of contract dollars awarded to women‐ and minority‐owned firms. Using the theory of representative bureaucracy as a starting point, they find evidence that increases in passive minority representation result in a larger proportion of contract dollars awarded to minority‐owned firms, which comports with previous empirical research. There is no evidence, however, that female representation leads directly or indirectly to substantive benefits for women‐owned small businesses. Given that the findings for women do not support representative bureaucracy, the authors provide potential alternative explanations. Specifically, they consider gender bias, social identity, and the “queen bee” phenomenon as possible explanations for why women are less inclined to advocate for other women.  相似文献   
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Research indicates that parents’ solicitation and adolescents’ disclosure of information are negatively associated with adjustment problems (depressive symptoms and conduct problems). However, few studies examine the bidirectional associations between these variables with early adolescents in the United States or the race/ethnic group differences in these bidirectional associations. We examined cross-lagged associations and race/ethnic group differences between parents’ solicitation, adolescents’ disclosure and adjustment problems among 209 non-Hispanic White (61.2%) and Hispanic (38.8%) early adolescents (67.5% female) across a 1-year period. The findings indicated that adolescents’ disclosure was negatively associated with subsequent depressive symptoms, while parents’ solicitation was positively associated with subsequent depressive symptoms. No significant race/ethnic group differences were indicated. Family-based interventions should encourage adolescents to disclose information to parent(s) due to its promotive capabilities.  相似文献   
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Oral fluid (collected with the Intercept((R)) device) and plasma samples were obtained from 139 individuals suspected of driving under the influence of drugs and analyzed for Delta(9)-tetrahydrocannabinol (THC), the major psychoactive constituent of cannabis, using a validated quantitative LC-MS-MS method. The first aim of the study was to investigate the correlation between the analytical data obtained in the plasma and oral fluid samples, to evaluate the use of oral fluid as a 'predictor' of actual cannabis influence. The results of the study indicated a good accuracy when comparing THC detection in oral fluid and plasma (84.9-95.7% depending on the cut-off used for plasma analysis). ROC curve analysis was subsequently used to determine the optimal cut-off value for THC in oral fluid with plasma as reference sample, in order to 'predict' a positive plasma result for THC. When using the LOQ of the method for plasma (0.5 ng/mL), the optimal cut-off was 1.2 ng/mL THC in oral fluid (sensitivity, 94.7%; specificity, 92.0%). When using the legal cut-off in Belgium for driving under the influence in plasma (2 ng/mL), an optimal cut-off value of 5.2 ng/mL THC in oral fluid (sensitivity, 91.6%; specificity, 88.6%) was observed. In the second part of the study, the performance of the on-site Dr?ger DrugTest for the screening of THC in oral fluid during roadside controls was assessed by comparison with the corresponding LC-MS-MS results in plasma and oral fluid. Since the accuracy was always less than 66%, we do not recommend this Dr?ger DrugTest system for the on-site screening of THC in oral fluid.  相似文献   
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We present a validated method for the simultaneous analysis of basic drugs which comprises a sample clean-up step, using mixed-mode solid-phase extraction (SPE), followed by LC–MS/MS analysis. Deuterated analogues for all of the analytes of interest were used for quantitation. The applied HPLC gradient ensured the elution of all the drugs examined within 14 min and produced chromatographic peaks of acceptable symmetry. Selectivity of the method was achieved by a combination of retention time, and two precursor-product ion transitions for the non-deuterated analogues. Oral fluid was collected with the Intercept®, a FDA approved sampling device that is used on a large scale in the US for workplace drug testing. However, this collection system contains some ingredients (stabilizers and preservatives) that can cause substantial interferences, e.g. ion suppression or enhancement during LC–MS/MS analysis, in the absence of suitable sample pre-treatment. The use of the SPE was demonstrated to be highly effective and led to significant decreases in the interferences. Extraction was found to be both reproducible and efficient with recoveries >76% for all of the analytes. Furthermore, the processed samples were demonstrated to be stable for 48 h, except for cocaine and benzoylecgonine, where a slight negative trend was observed, but did not compromise the quantitation. In all cases the method was linear over the range investigated (2–200 μg/L) with an excellent intra-assay and inter-assay precision (coefficients of variation <10% in most cases) for QC samples spiked at a concentration of 4, 12 and 100 μg/L. Limits of quantitation were estimated to be at 2 μg/L with limits of detection ranging from 0.2 to 0.5 μg/L, which meets the requirements of SAMHSA for oral fluid testing in the workplace. The method was subsequently applied to the analysis of Intercept® samples collected at the roadside by the police, and to determine MDMA and MDA levels in oral fluid samples from a controlled study.  相似文献   
60.
The chief clinical and analytical aspects of the suicide of a 21-year-old male with psychiatric problems by parenteral administration of a 200 g/l aqueous solution of paraquat are described. Paraquat levels were determined in plasma, urine, kidney, liver and lung after autopsy. Tissue damage was studied by electron microscopy. The death ensued from pulmonary dysfunction 15 days after hospital admission.  相似文献   
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