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151.
The true impact of heat-induced changes in human bone regarding their sex estimation has not been comprehensively documented having a potentially negative impact on forensic anthropology. The objective of this paper was to evaluate how heat exposure affects sex estimation based on both morphological and metric features. The study focused in both low-to-medium intensity burns and high intensity burns. Selected sexually dimorphic features were analysed in 51 experimentally burnt skeletons from the 21st Century Identified Skeletal Collection. Bones were burnt to maximum temperatures between 450 °C and 1050 °C achieved after 75 to 257 min. Morphological methods tested in this study comprised the recommendations for hipbone features from Buikstra and Ubelaker (1994) and from Bruzek (2002). On the other hand, metric references tested here were the ones from Wasterlain (2000), Curate et al. (2016) and Gonçalves et al. (2013) focused on the humerus, femur, calcaneus and talus. Agreement was tested with Gwet’s AC1 test and was further assessed by calculating the relative amount of perfect agreements. Results demonstrated that heat-induced changes affected not only the scoring of morphological features burnt at high temperatures but also the scoring of features burnt at lower intensities. On the other hand, metric features were only considerably affected in high intensity burns, no major changes being documented for low-to-medium intensity burns. For low-to-medium intensity burns, the Bruzek and Curate et al. methods revealed a better agreement between the pre- and post-burning scores. For high intensity burns, better agreement was obtained by using the Bruzek (2002) and Gonçalves et al. (2013) methods. As expected, heat-induced warping, fracture and metric change had a major impact on the pre- and post-observations’ agreement. Contrary to what has been systematically assumed over the years, this impact is also quite substantial in bones burnt at low-to-medium burn intensities so caution is advised during the analysis of this kind of burnt skeletal material.  相似文献   
152.
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   
153.
Though political scientists generally understand the origins of native‐born reactions to foreigners, less is known about how anti‐immigrant contexts trigger a political response within immigrant groups. I address this question by studying the connection between xenophobic rhetoric and Latino politics. I claim that xenophobic rhetoric raises the salience of ethnic identity and impugns its worth. This identity threat leads high‐identifying group members to engage in political efforts that assert their group's positive value, whereas low identifiers shun political opportunities to bolster their group's devaluation. I test these claims with an experiment embedded in a nationally representative opinion survey of Latino adults. In light of xenophobic rhetoric, I find that relative to low identifiers, high‐identifying Latinos become less politically trusting, more ethnocentric, and increasingly supportive of policies that emphasize ingroup pride. These results clarify xenophobic rhetoric's role in amplifying the influence of ethnic identity on immigrant politics.  相似文献   
154.
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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157.
This study analyses the extent, sense, and strategies employed by sympathisers with Spanish state-wide left-wing parties to ‘reconstruct’ their affective ties with the Spanish nation after the ‘monopolisation of patriotism’ by Franco's regime. Such an undertaking is further complicated within the context of economic crisis and intensified peripheral nationalism found in Catalonia and the Basque Country. This article applies qualitative analysis to the discourse of left-wing participants from 11 focus groups held in March 2012 amidst the economic (and political) crisis. As expected, this context of crisis favoured the emergence of explicit discourse on the Spanish nation, providing an opportunity to gain a better understanding of its nature. Findings show that welfare nationalism and social patriotism define the kind of attachment developed by the interviewees towards Spain better than the concept of constitutional patriotism, or any kind of ethnic-cultural feeling of belonging.  相似文献   
158.
Relations between the European Union (EU) and regional subgroups in Latin America (Mercosur, the Andean Community and Central America) are clear examples of ‘pure interregionalism’ and provide evidence of the EU's active promotion of regional integration. Within the context of these cases, this article explores what type of international power the EU wields, how interregionalism is embedded in that power, and how it is deployed. Combining strands of literature on EU–Latin American relations, interregionalism, EU external policy and power provides a framework within which interregionalism can be understood as an important normative and practical tool for the EU's external power projection. Drawing on official documentation and interviews with key individuals, the paper highlights the EU's articulation of power in interregional relations and reflects upon its mixed success. It concludes that, while imperial qualities and aspirations can be observed in the EU's penchant for interregionalism, the transformative power of the EU remains limited.  相似文献   
159.
The extraction of DNA from human skeletal remains applied to forensic, and evolutionary studies do not exclude risks, which are to be evaluated when working with unique specimens that could be damaged or even destroyed. In the present study were evaluated several nondestructive methods for recovering DNA instead of the most currently used pulverization method. Three different procedures to access inside the dental pieces (occlusal perforation, cervical perforation, and cervical cut) have been compared with the aim of recovering as many cell remains as possible to carry out a DNA extraction. Given the DNA quantitation results, a method was proposed that consists of a cervical cut to facilitate the access to the pulp cavity and a subsequent filing of the root canals down to the apex of the dental root. This methodology allows the recovery of both mitochondrial and nuclear DNA, with the minimum deterioration for the dental pieces.  相似文献   
160.
Since 1998, over 5500 people have died while attempting to cross the U.S.–Mexico border without authorization. These deaths have primarily occured in the Arizona desert. Despite the high volume of deaths, little experimental work has been conducted on Sonoran Desert taphonomy. In this study, pig carcasses were used as proxies for human remains and placed in different depositional contexts (i.e., direct sunlight and shade) that replicate typical sites of migrant death. Decomposition was documented through daily site visits, motion-sensitive cameras and GIS mapping, while skeletal preservation was investigated through the collection of the remains and subsequent faunal analysis. Our results suggest that vultures and domestic dogs are underappreciated members of the Sonoran scavenging guild and may disperse skeletal remains and migrant possessions over 25 m from the site of death. The impact of scavengers and the desert environment on the decomposition process has significant implications for estimating death rates and identifying human remains along the Arizona/Mexico border.  相似文献   
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