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241.
A method has been developed for the rapid extraction of cocaine and benzoylecgonine from post-mortem blood and urine samples. Solid phase columns containing C8 packing material gave clean, emulsion free extracts from body fluids. The total time for each extraction was approx. 10 min and the system has the capacity for the simultaneous extraction of up to 10 samples. Urine can be extracted directly, blood samples were sonicated before extraction to allow for their easy passage through the columns. The method gave excellent recoveries of cocaine (98-100%) from spiked samples at concentrations of between 50 ng/ml and 10 micrograms/ml. Analysis of the extracts was by high performance liquid chromatography (HPLC). 相似文献
242.
This paper describes a simplified approach to calculating the Bayesian likelihood ratio for the case where two DNA single locus profiles are to be compared. It explains how the calculation allows for band shift and also for the variation in precision with molecular weight. A simple basic theory section explains the principles of the analysis but more detailed explanations are given in an advanced theory section. Experiments on substantial data collections are described which demonstrate the robustness of the method. 相似文献
243.
A small experiment is described which uses databases of Afro-Caribbeans and Caucasians to establish the quality of information that might be given to an investigator about the ethnic group of the donor of an unknown crime stain. The results show that the technique can provide qualified indications, but categoric conclusions are not, in general, feasible. An appraisal is given of the technique within the operational context. 相似文献
244.
Dorothy L. Espelage Kathleen C. Basile Ruth W. Leemis Tracy N. Hipp Jordan P. Davis 《Journal of youth and adolescence》2018,47(9):1880-1893
The Bully-Sexual Violence Pathway theory has indicated that bullying perpetration predicts sexual violence perpetration among males and females over time in middle school, and that homophobic name-calling perpetration moderates that association among males. In this study, the Bully-Sexual Violence Pathway theory was tested across early to late adolescence. Participants included 3549 students from four Midwestern middle schools and six high schools. Surveys were administered across six time points from Spring 2008 to Spring 2013. At baseline, the sample was 32.2% White, 46.2% African American, 5.4% Hispanic, and 10.2% other. The sample was 50.2% female. The findings reveal that late middle school homophobic name-calling perpetration increased the odds of perpetrating sexual violence in high school among early middle school bullying male and female perpetrators, while homophobic name-calling victimization decreased the odds of high school sexual violence perpetration among females. The prevention of bullying and homophobic name-calling in middle school may prevent later sexual violence perpetration. 相似文献
245.
Gerie W. Palanca 《Astropolitics》2018,16(2):141-156
The number of objects in Earth’s orbit has continued to grow since the space race between the United States and the Soviet Union. The historical “few objects, large space” principle left satellite operations a relatively benign environment, but that construct has shifted significantly due to the advent of the commercial space sector, the small satellite industry boom, and the resurgence of the desire for human space flight. The regulations for space operations both at the international and national level have always been sparse, but there is a large desire for more now that commercial capital is at stake. The purpose of this article is to bring to the surface available regulations for on-orbit operations to identify the gaps to fill and highlight the change for the Department of Defense. The international community and commercial sector recognize the need for a state like the United States to set a standard to influence the international community. This national-to-international framework is a technique used in other arenas, such as maritime traffic management and air traffic management, and the lessons learned from these fields are applicable to the space domain. 相似文献
246.
247.
William C. Cockerham Bryant W. Hamby Olena Hankivsky Elizabeth H. Baker Setareh Rouhani 《Communist and Post》2017,50(1):53-63
The ongoing health crisis in the Ukraine has persisted for 48 years with a clear division of gender-based outcomes as seen in the decline of male life expectancy and stagnation of female longevity. The purpose of this paper is to investigate differences in self-rated health and system barriers to health care applicable to gender and its intersections because of the differing negative health outcomes for men and women. Intersectionality theory provides an analytic framework for interpreting our results. Utilizing a nationwide sample of the Ukrainian population (N = 1908), we found that low socioeconomic status (SES) women rate their health worse than men generally and any other socioeconomic group. Yet women also face the greatest barriers to health care until older ages when the ailments of men cause them to likewise face the obstacles. In reviewing the barrier to health care scale, one barrier—that of health care services being too expensive—dominated the responses with some 52.5 percent of the sample reporting it. Consequently, the greatest problem in Ukraine with respect to health reform reported by the population is the out-of-pocket costs for care in a system that is officially free. These costs, constituting some 40 percent of all national health expenditures, affect women and the aged the most. 相似文献
248.
This article analyzes how the idea of “innovationism” in Sweden has generated a new kind of idea-driven policy around the creation of innovative regional policy. In contrast to similar policies in this area, this policy does not manifest itself through traditional instruments, but evolves through symbolic and ritual performances, in particular through events and conferences. The article asks how this emerging idea has changed the existing institutional formation of sponsoring industrially relevant research. The vision of concerted action between decision-makers within modern innovationism reinforces territorial identity, but it also tends to devolve responsibility to the regional level since concerted action on the national level is hard to obtain. What emerges is a system of governing at a distance where different actors perform their roles according to often academic ideas of innovationism. The study is based on two qualitative studies in Sweden entailing both documentary sources and semi-structured interviews. 相似文献
249.
The article examines the subject of homegrown violent extremism related to militant Islamism in the dual-Island Caribbean state of Trinidad and Tobago (T & T). It employs original research drawn from a series of semi-structured interviews and focus groups conducted between November 2015 and January 2016. Tracing the evolution of endogenous forms of radicalism and extremism the article considers how globalized-exogenous forms of militant Islamism associated with Al Qaeda and its offshoots, such as the so-called Islamic State, have impacted local patterns of violent extremism. The case study draws attention to a state and a region that have received scant attention in terrorism studies. As demonstrated by the article, this oversight is imprudent. There are a number of noteworthy findings from this case study for terrorism studies scholars: the unique historical legacy of radicalism, extremism and insurrection among T & T's Islamists; the country's markedly high levels of extremist travelers on a per capita basis and the high rate of religious converts among those travelers; the inter-linkages between criminality and political violence; and the potential threat posed by Trinidadian and Tobagonian militancy regionally. 相似文献
250.
Multilateral negotiations at the World Trade Organization have stalled. This has contributed to a steep rise in preferential trade agreements (PTAs). At the same time, negotiations for PTAs have not always proven quick and painless: While some treaties are sealed within a few months or days only, other agreements are preceded by protracted bargaining processes in trade and trade-related issue areas. In this article, we provide a theoretical explanation for this empirical variation. More specifically, we argue that PTA negotiations take longer the greater the distance between the prospective partners’ initial bargaining positions. Moreover, we contend that negotiation processes become more protracted the higher the relative ambition of the prospective PTA. Due to the limited links to the domestic political arena in autocracies, we expect this latter effect to play out for groups of democratic bargaining partners only. We test these two hypotheses for 198 preferential trade negotiations using novel measures for bargaining templates and the ambition of PTA clauses. In our two-stage survival models, we find support for our argument. In line with qualitative evidence from recent preferential trade initiatives, our models indicate that services, investment and intellectual property rights are particularly sticky agenda items for democratic leaders at the international bargaining table. 相似文献