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911.
Public Choice - A theoretically grounded approach to causal questions illuminates both the utility and limitations of the potential outcomes (PO) framework as a model for historically-focused,... 相似文献
912.
913.
Andrew M. Sacha BS Isaac C. Willis BS Victoria L. McGuffin PhD Ruth Waddell Smith PhD 《Journal of forensic sciences》2023,68(5):1527-1541
Definitive identification of fentanyl analogs based on mass spectral comparison is challenging given the high degree of structural and, hence, spectral similarity. To address this, a statistical method was previously developed in which two electron-ionization (EI) mass spectra are compared using the unequal variance t-test. Normalized intensities of corresponding ions are compared, testing the null hypothesis (H0) that the difference in intensity is equal to zero. If H0 is accepted at all m/z values, the two spectra are statistically equivalent at the specified confidence level. If H0 is not accepted at any m/z value, then there is a significant difference in intensity at that m/z value between the two spectra. In this work, the statistical comparison method is applied to distinguish EI spectra of valeryl fentanyl, isovaleryl fentanyl, and pivaloyl fentanyl. Spectra of the three analogs were collected over a 9-month period and at different concentrations. At the 99.9% confidence level, the spectra of corresponding isomers were statistically associated. Spectra of different isomers were statistically distinct, and ions responsible for discrimination were identified in each comparison. To account for inherent instrument variations, discriminating ions for each pairwise comparison were ranked based on the magnitude of the calculated t-statistic (tcalc) value. For a given comparison, ions with higher tcalc values are those with the greatest difference in intensity between the two spectra and, therefore, are considered more reliable for discrimination. Using these methods, objective discrimination among the spectra was achieved and ions considered most reliable for discrimination of these isomers were identified. 相似文献
914.
915.
How does civic education affect the development of democratic political culture in new democracies? Using a unique three‐wave panel data set from Kenya spanning the transitional democratic election of 2002, we posit a two‐step process of the social transmission of democratic knowledge, norms, and values. Civic education first affected the knowledge, values, and participatory inclinations of individuals directly exposed to the Kenyan National Civic Education Programme (NCEP). These individuals became opinion leaders, communicating these new orientations to others within their social networks. Individuals who discussed others’ civic education experiences then showed significant growth in democratic knowledge and values, in many instances more than individuals with direct exposure to the program. We find further evidence of a “compensation effect,” such that the impact of civic education and post‐civic education discussion was greater among Kenyans with less education and with lower levels of social integration. 相似文献
916.
Smith SD 《Journal of law and medicine》2007,15(3):434-449
The "health rights movement" has reconstructed the clinical relationship between health care workers and patients by simultaneously demanding more from traditional medical care and challenging the perceived power differential between doctors and patients by rejecting the paternalistic medical model in favour of an individual patients' rights model. However, the growth in individual expectations of a right to health care creates a potential conflict with the ethics that prioritise public health and guide the rationing of its limited financial and human capital resources. This, in turn, creates a practical dilemma which requires public health institutions to become service orientated while sacrificing their integral role in training and educating the medical workforce and potentially compromising the practical sustainable delivery of public health in Australia. However, the law can play a role in resolving this conflict through legislation, regulations, codes, administrative law and common law in an effort to ensure the quality and future sustainability of public health in Australia. 相似文献
917.
918.
Oxley JC Smith JL Kirschenbaum LJ Marimiganti S Efremenko I Zach R Zeiri Y 《Journal of forensic sciences》2012,57(3):623-635
This study extends previous work on the sorption of explosives to the hair matrix. Specifically, we have studied the interaction of 2,4,6-trinitrotoluene (TNT) and triacetone triperoxide (TATP) as a function of chemical pretreatment with acetonitrile, neutral and alkaline hydrogen peroxide, methanolic KOH and potassium permanganate, and the morphological changes that accompany these treatments. While differences in vapor pressure can account for quantitative differences between TNT and TATP sorption, both are markedly affected by the chemical rinses. Examination of the hair surface shows different degrees of smoothening following rinsing, suggesting that the attachment to hair is largely a surface phenomenon involving the 18-methyleicosanoic acid lipid layer. Density functional theory calculations were employed to explore possible nucleation sites of TATP microcrystals on the hair. We conclude that some of the sites on melanin granular surfaces may support nucleation of TATP microcrystals. Moreover, the calculations support the experimental finding that dark hair adsorbs explosives better than light hair. 相似文献
919.
Stepp SD Smith TD Morse JQ Hallquist MN Pilkonis PA 《Journal of interpersonal violence》2012,27(1):103-124
This study examined the prospective relationships among borderline personality disorder (BPD) symptoms, interpersonal problems, and types of aggressive behaviors (i.e., experiencing psychological and physical victimization and perpetrating psychological and physical aggression) in a psychiatric sample (N = 139) over the course of 2 years. We controlled for other PD symptoms and demographic variables. BPD symptoms at baseline were associated with interpersonal sensitivity, interpersonal ambivalence, interpersonal aggression, need for social approval, and lack of sociability 6 months later. In turn, interpersonal sensitivity predicted not experiencing physical aggression, interpersonal aggression predicted experiencing physical aggression and perpetrating both psychological and physical aggression, need for social approval predicted experiencing both psychological and physical aggression, and lack of sociability predicted perpetrating physical aggression 2 years later. Results demonstrated that interpersonal problems mediated the relationship between BPD and later violent behaviors. Our findings suggest the importance of distinguishing between these groups of aggressive behaviors in terms of etiological pathways, maintenance processes, and treatment interventions. 相似文献
920.
Peter K. Smith Christina Salmivalli Helen Cowie 《Journal of Experimental Criminology》2012,8(4):433-441