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161.
Impurities in 48 methamphetamine (MA) samples were analyzed by liquid-liquid extraction (LLE) and headspace solid-phase microextraction (HS-SPME) methods. MPS-2 autosampler was used to improve reproducibility of SPME method, and nonadecane (C(19)) diluted with potassium bromide (KBr) powder was used as an internal standard for standardizing retention time. Impurities identified by SPME method showed different patterns compared with LLE method. Non-volatile impurities like methamphetamine dimer were not identified by SPME method, but some volatile impurities like diphenylketone, caprolactam and lots of unknowns were identified only by SPME method. 1-Phenyl-2-propanone (P2P), 1-phenyl-2-propanol and benzylcyanide peaks could be discriminated clearly by SPME method without interference of amphetamine, an artifact originates from MA degradation. Differences in the impurity patterns resulted in different clustering results. When 48 MA samples were classified into 5 LLE and 5 SPME clusters, cross-matching of the clusters resulted in 8 sub-clusters. It shows that combination of the different extraction methods can distinguish the differences which cannot be distinguished by LLE or SPME method alone, and can improve reliability of the profiling results.  相似文献   
162.
Previous research by the authors on an animal model showed that bloodstains can contain additional information about their somatic origin in the form of wound cells. Bloodstains produced by a gunshot wound to the head were distinguished from bloodstains produced by a gunshot wound to the chest by testing the stains for a brain microRNA marker. In this study, the effectiveness of the technique was examined on blood drops shed externally from a stab wound to the liver of rat carcasses. Specifically, investigations were conducted on the liver microRNA marker, rno‐mir‐122‐3p, with the QIAGEN miScript System, and PCR analysis. Between the two stabbing methods used, 67% of the scalpel blades and 57% of the blood drops tested positive for rno‐mir‐122‐3p; however, other samples tested negative giving inconclusive results as to the wound‐of‐origin. The amount of the liver cells in the bloodstains appeared to be related to the extent of trauma.  相似文献   
163.
Traditional studies of the Japanese bureaucracy have emphasized effective governance through a close government–business nexus. Yet this network relation creates corruption, especially at a high level of administration. Adopting an organizational network approach, this article provides a critical analysis of the causality between network structures and administrative corruption. Examining financial and public works policies, this article finds that amakudari- and zoku-driven network relationships, which have been reinforced by sociocultural bases, are vertically and exclusively structured and substantiate corruption in administration. Policy making on the basis of such network relations not only results in mismanagement in administration and the distortion of the market disciplines but also delegitimizes the governance system by destroying public trust in government. This article suggests that bringing greater heterogeneity and citizen participation to administration through diversity management and e-government would reduce administrative corruption in Japanese governance.  相似文献   
164.
Power and Cognitive Accuracy in Local Emergency Management Networks   总被引:1,自引:0,他引:1  
Using network power bases and cognitive accuracy concepts, this study examines two local emergency management network changes. The authors review five power bases—structural-based, resource-based, actor-based, cognitive-based, and political-based power—to explore the perceived power of network actors. Three research propositions are proposed with respect to the relationship between the network power bases and the cognitive accuracy of network participants. The authors find that political-based power is strongly correlated with perceived power. The article concludes with future research questions and directions for advancing current scholarship on emergency management networks.  相似文献   
165.
166.
Cultural differences have been found in body image perceptions among Black and White adolescents, however little is known about the factors associated with perceptions of an ideal body size (IBS). This study examined differences in correlates of IBS among 265 Black (116 girls and 62 boys) and White (63 girls and 24 boys) adolescents. IBS for White girls and boys was related to perceptions of how their parents wanted them to look, while IBS for Black girls was related to perception of how peers look and would like to look. IBS for Black boys was significantly related to perceptions of their current size, how peers would like to look, how parents think they look, and depressive symptoms. Findings suggest cultural differences in the factors related to body image perceptions and have implications for educational programs promoting healthy body image development among Black and White adolescents.Assistant Professor, Department of Preventive Medicine and Public Health, University of Kansas Medical Center. Received PhD in Counseling Psychology from University of Missouri-Kansas City. Research interests include environmental and cultural correlates of obesity, obesity prevention, nicotine and tobacco addiction, and health promotion interventions.Assistant Professor, Department of Pediatrics, University of Minnesota. Received medical degree from Christian Medical College, Punjab, India, and Master of Public Health from University of Kansas School of Medicine. Research interests include diet and physical activity behaviors, role of the environment in obesity and obesity prevention, especially among children and adolescents.Research Associate, Department of Preventive Medicine and Public Health, University of Kansas Medical Center. Completing PhD in clinical psychology from University of Kansas and Master of Public Health from University of Kansas School of Medicine. Research interests include obesity prevention, smoking cessation, and positive psychology.Assistant Professor and Director, MPH Program, Department of Preventive Medicine and Public Health, University of Kansas Medical Center. Received MPH from Boston University and PhD in epidemiology from the University of California/San Diego State University. Research interests include behavioral epidemiology of tobacco use among adolescents and ethnic minorities.Professor of Medicine and School of Public Health, University of Illinois at Chicago, Associate Director, Midwest Center for Health Services and Policy Research, Jesse Brown VA Medical Center, Director, Section of Health Promotion Research, Department of Medicine, University of Medicine, University of Illinois at Chicago. Received PhD in clinical psychology from Long Island University. Research interests include obesity prevention, binge eating, and cultural differences in eating behavior.Medical Epidemiologist, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention. Received MD and MPH from Tongji Medical University, Wuhan, China and PhD from University of Southern California Keck School of Medicine. Research interests include the etiology, epidemiology, and prevention ofobesity, metabolic syndrome, and diabetes.Research Instructor, Department of Preventive Medicine and Public Health, University of Kansas Medical Center. Received MBBS from Allama Iqbal Medical College, Punjab University, Lahore, Pakistan and MPH from University of Kansas Medical Center. Research interests include smoking cessation, database design, implementation, data management and analysis, and use of information technology in health care settings.Professor Department of Medicine and Office of Clinical Research, University of Minnesota School of Medicine. Received MD/MPH from Tulane University and MS from Harvard School of Public Health. Research interests include disparities in healthcare; smoking cessation among underserved populations, specifically African Americans; diet, nutrition, obesity, and physical activity.  相似文献   
167.
Dextromethorphan (DMP), an antitussive, is one of the most popular drugs among the younger generation in Korea. It usually is taken for its hallucinogenic properties and overdoses have been responsible for the fatalities that have been reported frequently. To control the abuse of DMP, the authorities restricted its use through classifying it as a controlled drug on October 2003. The purpose of this study is to provide a standard method for the analysis of DMP and its main metabolite, dextrorphan (DTP) in biological specimens. At first we established a standard operating procedure (SOP) for DMP/DTP in urine, and a method validation was performed. We also quantified DMP from 16 drug abuser's urine samples all of which were positive in the screening test for DMP. For the detection of DMP/DTP, urine samples were adjusted with 6N NaOH (pH 11) and extracted with ethylacetate. Thin layer chromatography was used as the screening test, and the final identification for DMP/DTP was used by GC/MS. The ions (m/z 271 for DMP, m/z 257 for DTP and m/z 86 for lidocaine as internal standard) were extracted from the full scan mass spectrum and were used for quantification. The selectivity, linearity of calibration, accuracy, within- and between day precision, limit of detection and quantification, recovery and stability were examined as parts of the method validation. Extracted calibration curves were linear from 100 to 2000 ng/mL for DMP and DTP with correlation coefficients better than 0.999. Limit detection was 50 ng/mL for DMP and DTP. Within-run precision (%CV) for DMP and DTP at three different concentrations (100, 500 and 1000 ng/mL) was 6.10-18.85%, and between-run precision was 1.70-7.86% for DMP and DTP. Absolute recovery for DMP and DTP was 57-74%, and relative recovery (extraction efficiency) was 80-89%. For 16 drug abuser's urine samples, the concentrations of DMP and DTP were 0.16-52.63 and 0.41-23.75 microg/mL, respectively. Method validation is an important requirement in the practice of chemical analysis, and it will be particularly useful in verifying the reliability of analytical results in the field of forensic science.  相似文献   
168.
169.
In this study, we explore the extent to which diversity of educational levels among research scientists and engineers (RSEs) in the context of a firm’s level of technological diversity influences innovation performance. We used data from the 2004–2008 National R&D Survey in Singapore. The results from 366 firms across different industries indicate that when a firm’s technological domains are heterogeneous, those firms with an RSE workforce comprising similar educational levels have positive innovation performance, measured as the number of patent applications, while those comprising diverse educational levels have negative innovation performance. Our further exploration of the positive interaction between technological domain heterogeneity and similarity of educational levels suggests that firms that had a high ratio of RSEs with lower educational levels had more positive patent outcomes compared to those that had a high ratio of RSEs with higher educational levels. The results show that there are limits to the strength of technological diversity in a firm’s absorptive capacity as explained by organizational demography.  相似文献   
170.
Researchers and mediators have long been concerned about coercion, intimidation, and safety threats that could occur in mediation for cases where previous violence between the parties has occurred. Most of the research focuses on screening tools to identify parties at risk. When parties screen positive for intimate partner violence (IPV), some proceed to mediation and some do not, depending on the policies of individual mediation programs. But this misses a step: Some cases may benefit from mediation while others won't, but how can we predict whether mediation will be useful and safe in specific instances? This study uses survey data obtained from parties in domestic relations mediations to examine issues of safety, satisfaction, and settlement in the presence of various IPV behaviors.  相似文献   
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