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281.
Darrell O. Ricke Ph.D. Philip Fremont‐Smith M.S. James Watkins B.S. Sara Stankiewicz M.S. Tara Boettcher B.S. Eric Schwoebel Ph.D. 《Journal of forensic sciences》2019,64(5):1468-1474
High‐throughput sequencing (HTS) of large panels of single nucleotide polymorphisms (SNPs) provides an alternative or complimentary approach to short tandem repeats (STRs) panels for the analysis of complex DNA mixture forensic samples. For STRs, methods to estimate individual contribution concentrations compare capillary electrophoresis peak heights, peak areas, or HTS allele read counts within a mixture. This article introduces three approaches (mean, median, and slope methods) for estimating individual DNA contributions to forensic mixtures for HTS/massively parallel sequencing (MPS) SNP panels. For SNPs, the major:minor allele ratios or counts, unique to each contributor, were compared to estimate contributor proportion within the mixture using the mean, median, and slope intercept for these alleles. The estimates for these three methods were typically within 5% of planned experimental contributions for defined mixtures. 相似文献
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The social welfare effects of legislatures in presidential systems, such as the U.S. Congress, are frequently lamented. In response, there are proposals to reform the separation of powers system by giving presidents control of the legislative agenda and weakening rules such as the filibuster. We provide a game-theoretic analysis of the policy and social welfare consequences of a more executive-centric system. Integrating standard assumptions about legislative and executive incentives into a dynamic model of decision making with private investment, we show there are a variety of conditions under which stronger executives do not produce better outcomes. Moreover, we characterize how these conditions depend on factors such as the stability of the policymaking environment or investment fundamentals. Our findings are robust and consistent with empirical observations that U.S. policy outputs are not necessarily worse than those of nations with stronger executives, which more closely approximate prominent proposals by populist-oriented reformers. 相似文献
284.
Civil wars are particularly destructive and asymmetric in nature. As a result, humanitarian crises and episodes of one-sided violence against civilians are likely to emerge. In the post-Cold War era, human rights norms have been strengthened by a global commitment stating that nations have a responsibility to protect people against war crimes. Although the doctrine does not require military responses, as episodes of one-sided violence increase dramatically in the midst of civil conflict, we would expect those cases to experience relatively swift foreign response, including military intervention; a growing trend of at least purportedly humanitarian interventions should be observable. Expectations relating to the responsibility to protect are tested on all civil conflicts occurring between 1989 and 2006. Findings indicate that there is little evidence that one-sided violence leads to military intervention, suggesting that the internationally community does not use its most powerful tool to protect civilians in trouble. 相似文献
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Joseph Y.S. Cheng 《当代中国》2015,24(92):357-375
The economic rise of the BRICS (Brazil, Russia, India, China and South Africa) inevitably leads to a redistribution of power in the international system. Chinese leaders today accord a considerable priority to this group, and there are elements of realism, liberalism/institutionalism and constructivism in their approach. This article intends to study China's policy towards BRICS and examine the above elements so as to better understand how the Chinese leadership perceives China's role in the international system, and how it seeks to articulate its interests and enhance its influence. 相似文献
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