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81.
Testing for the presence of cocaine (COC) is common in postmortem and clinical laboratories. COC use may be detected by screening urine specimens for COC metabolite. In the forensic arena, screening positive results are confirmed by a more specific and sensitive technique, such as gas chromatography-mass spectrometry. This article reports the case of an individual who died of COC intoxication but whose immunoassay screen (EMIT) for COC metabolite was negative. Gas chromatography-mass spectrometry analysis of the urine detected benzoylecgonine (BE) at a concentration of 75 ng/mL and COC at 55 ng/mL. These concentrations explain the negative screening result since the cutoff concentration of the assay was 300 ng/mL for BE. The reported cross reactivity with COC was 25,000 ng/mL. However, heart blood concentrations of COC and BE were 18,330 and 8640 ng/mL, respectively. The results from this case provide evidence that an EMIT test alone may fail to detect COC use. Individuals utilizing results of drug screening by immunoassay must be aware of the limitations of this testing methodology.  相似文献   
82.
Organizational culture is the pattern of values and beliefs held by members of an organization and the management of culture is now one of the most frequently discussed of all organizational concepts. The excitement associated with culture is attributable to two factors. First, it is argued that culture is the key to organizational performance; simply stated, a strong organizational culture can be a source of competitive advantage. Second, culture is perceived as an alternative method of control to traditional and technocratic forms of management and can be manipulated to ensure that employees are enthusiastic and committed to organizational objectives.
Despite the extensive interest in this topic, culture remains an elusive concept. This paper investigates the nature of culture and considers strategies for introducing cultural change. Specifically, the aims of the paper are threefold. First, to locate and explain the interests and significance of culture change for the public sector. Second, using a case study of a newly created agency, to investigate the problems and issues affecting cultural change in the civil service. Third, to reassess and critically evaluate the claims for culture management made in the literature. Finally, this paper questions some of the assumptions in the literature, which with few exceptions are biased toward top management and the unitary conception of organization, an ideological frame of reference which is particularly problematic in the public sector.  相似文献   
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This study developed a composite machine learning algorithm for attribution of materials of forensic interest (like ammonium nitrate) to original sources. k-nearest neighbor and random forest models were used for source elimination and classification, respectively, in a two-step, composite algorithm based on particle color, size/shape, and trace element concentration features. Novel approaches for simulation to supplement within-source reference features based on empirically measured multi-lot analyses, an improved hold-one-lot-out method for cross-validation, an assessment of the likelihood of the presence of a reference sample, fusion of the source probabilities from the respective classification models, and the calculation of metrics for assessing ensemble sourcing performance are described. Excellent sourcing predictions were obtained; the sourcing algorithm identified the correct source as the top choice 89% of the time, and the correct source was identified to be an average of 2.7 times more likely than the most likely incorrect source.  相似文献   
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86.
Analysis of information held by police, probation, and third-sector organizations in Wales about 100 domestic abuse perpetrators, along with 16 practitioner interviews, provides the empirical context for a discussion of the problem of “serial domestic abuse.” Despite increased concern over the harm caused by serial abusers, different definitions and recording systems prevent a reliable estimation of the problem. This exploratory study suggests that the offending profiles of serial abusers are heterogeneous, and recommends that approaches aimed at reducing the harm caused by the “power few” domestic abusers incorporate information about serial alongside repeat and high-risk offending.  相似文献   
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88.
The period 1880–1930 saw women composers achieve unprecedented prominence as composers of large-scale works. This success coincided with the first wave of feminist movements in England, France and Germany. This article views the junctions where these two groups of women met through the vehicle of the feminist press, documenting the tensions and misunderstandings that occurred between emerging women composers attempting to be taken seriously as creative entities and feminists seeking to improve the political, social and professional lot of women. The pervasive aesthetic of male musical genius remained unquestioned by many feminists in spite of examples of female creative brilliance.  相似文献   
89.
While having a purpose in life has been theorized as a developmental asset, the extent to which adolescents cultivate a meaningful sense of direction is not well understood. In the present study, cluster analysis was used to classify adolescents by levels of purpose exploration and commitment. The sample (N = 318; 55% female) consisted of youth aged 14–18 and was predominantly White/non-Hispanic (76.3%). Results supported four meaningful yet distinguishable profiles of youth purpose that are largely consistent with theories on identity formation: Achieved, Foreclosed, Uncommitted, and Diffused. Hypothesized linkages with affect and hope were established across the profiles such that positive emotions and goal-directed thinking were most apparent among Achieved and Foreclosed youth and least apparent among Diffused and Uncommitted youth. Overall, findings demonstrate the inherent complexity in adolescents’ engagement with purpose and suggest a correspondence between stronger commitments to purpose and youths’ sense of personal agency and well-being.  相似文献   
90.
Supreme Court confirmation hearings have been famously called a “vapid and hollow charade” by Elena Kagan. Indeed, perceptions of nominees’ refusal to answer questions about pending cases, prominent political issues, or give any hint of their ideological leanings have become a cornerstone of the modern confirmation process. We investigate the extent to which this reticence to speak of their ideological views, or candor, influences how individuals evaluate the nominee. To this end, we present the results of a survey experiment which examines how support for a hypothetical Supreme Court nominee is affected by information, especially when a nominee is presented to be very forthright or very reticent in answering ideological questions during the confirmation hearings. We find that while partisan compatibility with the president is the main determinant of support for a nominee, nominees who refuse to answer ideological questions can bolster support from respondents who would not support them on partisan grounds. We supplement these findings with observational state-level support data from real nominees over the last 40 years.  相似文献   
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