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Journal of Youth and Adolescence - Knowing the extent to which mental well-being and stressful life events during adolescence contribute to personality characteristics related to risk-taking...  相似文献   
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Studying dipterans at the scene of a death can provide essential information for interpreting the evidence and help to reconstruct the events happened to a corpse in the past. Molecular tools have been employed for identification at specific levels in the cases of cryptic species or poorly conserved specimens. Identification of specimens is essential in forensic entomology since each species has a specific growth rate, which determines the calculation of the minimum post mortem interval (minPMI). In addition, phylogeographic reconstruction within a species can help to differentiate the haplotypes from a geographic area, thereby helping to clarify the possible relocation of a corpse. The morphological identification of Sarcophagidae species is often difficult, especially for the females. This is an important Diptera family since some of its species are among the first to reach a corpse, especially in warm areas. In this study, we compared the sarcophagids found in human corpses in forensic cases in Alicante (southeast of Spain) with specimens collected from baited traps in the same area and surrounding provinces. In total, 189 specimens were collected, comprising 72 from forensic cases and 117 from baited traps. Molecular identification was conducted by sequencing the cox1 mitochondrial gene and analyzing the sequences using ABGD, GMYC, and BIN species delimitation methods. The median joining algorithm in the PopART program was used to construct phylogeographic networks. Eight species in the family Sarcophagidae were identified. The most widely collected species were Sarcophaga argyrostoma and Sarcophaga tibialis. The haplotype networks obtained for these species did not indicate a clear geographic distribution of haplotypes. The S. argyrostoma samples from Alcoy were clearly isolated. The results demonstrated that this method is useful for identifying Sarcophagidae samples in forensic investigations and it can be employed for minPMI estimation.  相似文献   
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Existing research highlights that families face geographic, social, and psychological constraints that may limit the extent to which competition can take hold in school choice programs. In this paper, we address the implications of such findings by creating a network of student flows from 11 cohorts of eighth‐grade students in the Chicago Public Schools (CPS). We applied a custom algorithm to group together schools with similar sending and receiving patterns, and calculated the difference in mean achievement between a student's attended and assigned high schools. For all identified school groupings, we found that the students were on average moving to higher achieving schools. We also found that the movement toward higher achieving schools of the top achievement quartile of students was over twice as large as that of the bottom quartile, but that the flows of both the highest and lowest achieving student quartiles were toward higher achieving destinations. Our results suggest that student movements in CPS between the years of 2001 to 2005 were consistent with creating market pressure for improvement as well as increasing segregation by achievement. However, further research into how schools responded to those movements is required to make inferences about the level or consequences of competition generated by choice‐related reforms during that time.  相似文献   
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