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In a seminal article, Cox (1990) suggested that electoral systems with larger district magnitudes provide incentives for parties to advocate more extreme policy positions. In this article, we put this proposition to the test. Informed by recent advances in spatial models of party competition, we introduce a design that embeds the effect of electoral rules in the utility function of voters. We then estimate the equilibrium location of parties as the weight voters attach to the expected distribution of seats and votes changes. Our model predicts that electoral rules affect large and small parties in different ways. We find centripetal effects only for parties that are favorably biased by electoral rules. By contrast, smaller parties see their vote share decline and are pushed toward more extreme equilibrium positions. Evidence from 13 parliamentary democracies supports model predictions. Along with testing the incentives provided by electoral rules, results carry implications for the strategies of vote‐maximizing parties and for the role of small parties in multiparty competition.  相似文献   
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In forensic analyses, determining the level of consensus among examiners for hair comparison conclusions and ancestry identifications is important for assessing the scientific validity of microscopical hair examinations. Here, we present data from an interlaboratory study on the accuracy of microscopical hair comparisons among a subset of experienced hair examiners currently analyzing hair in forensic laboratories across the United States. We examined how well microscopical analysis of hair can reliably be used to differentiate hair samples, many of which were macroscopically similar. Using cut hair samples, many sharing similar macroscopic and microscopic features, collected from individuals who share the same mitochondrial haplogroup as an indication of genetic relatedness, we tested multiple aspects that could impact hair comparisons. This research tested the extent to which morphological features related to ancestry and hair length influence conclusions. Microscopical hair examinations yielded accurate assessments of inclusion/exclusion relative to the reference samples among 85% of the pairwise comparisons. We found shorter hairs had reduced levels of accuracy and hairs from populations examiners were not familiar with may have impacted their ability to resolve features. The reliability of ancestry determinations is not yet clear, but we found indications that the existing categories are only somewhat related to current ethnic and genetic variation. Our results provide support for the continued utility of microscopical comparison of hairs within forensic laboratories and to advocate for a combined analytical approach using both microscopical analysis and mtDNA data on all forensic analyses of hair.  相似文献   
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There has been burgeoning interest in psilocybin-use for the treatment of various neurological and neurodegenerative diseases. Psilocybin is mistakenly perceived as the principal pharmacologically active compound due to its high concentrations found in magic mushrooms; however, it is the prodrug of psilocin. Despite the expanding body of clinical research seeking to understand the pharmacodynamic/pharmacokinetic properties of psilocin, and its role in inducing dramatic changes to cognitive function, there has not been a corresponding increase in the development of sensitive analytical methods that can quantify psilocin in different biological fluids. Existing analytical methods have been developed using plasma, serum, and urine as the matrix of choice, but with the unknown blood-to-plasma ratio of psilocin, any pharmacokinetic conclusions drawn solely on plasma data may be misleading. Thus, the main objective of this study is to develop the first analytical method that utilizes SPE and LC–MS/MS to quantify psilocin in human whole blood. The SPE procedure yielded a high recovery efficiency (≥89%) with minimal matrix effects. The method was validated according to ANSI/ASB 036 guidelines. Linearity was between 0.7–200 ng/mL and encompassed previously reported ranges found in plasma/serum. Bias, within- and between-run precision for all quality controls met ANSI/ASB 036 acceptability criteria. Endogenous/exogenous interferences and carryover were negligible. Psilocin stability was assessed at 4°C over 48 h and was considered stable. Although a proof-of-concept study will need to be performed to characterize the method, this analytical workflow was able to detect and quantify psilocin in human whole blood at low limits of quantification.  相似文献   
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This case study reports a fatal subarachnoid hemorrhage (SAH) with concomitant accidental carbon monoxide (CO) exposure in 32‐year‐old man. Autopsy results indicated an antemortem aspiration of smoke, and a massive SAH was identified as the cause of death. Intriguingly, the carboxyhemoglobin level was 30%, suggesting that CO could have played a specific role. Intracranial hemorrhages following CO exposure in brain areas and tissues such as the basal ganglia, globus pallidus, or white matter are rare, but well characterized, whereas SAH related to CO exposure has not been previously described. In this case report, the possible role of CO, either as a primary cause or as a facilitating factor, in the pathogenesis of SAH is discussed. In particular, we propose the hypothesis that the excessive vasodilating effects produced by CO on the cerebral endothelium results in consequential loss of microvascular integrity.  相似文献   
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