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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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In recent years, a widespread consensus has emerged about the necessity of establishing bridges between quantitative and qualitative approaches to empirical research in political science. In this article, we discuss the use of the synthetic control method as a way to bridge the quantitative/qualitative divide in comparative politics. The synthetic control method provides a systematic way to choose comparison units in comparative case studies. This systematization opens the door to precise quantitative inference in small‐sample comparative studies, without precluding the application of qualitative approaches. Borrowing the expression from Sidney Tarrow, the synthetic control method allows researchers to put “qualitative flesh on quantitative bones.” We illustrate the main ideas behind the synthetic control method by estimating the economic impact of the 1990 German reunification on West Germany.  相似文献   
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This study sought to analyse the relation between executive functions and criminal recidivism. We assessed a set of cognitive abilities associated with executive functioning in a group of recidivist offenders (n = 19), primary offenders (n = 25) and non-offenders (n = 30). Our results, tested with nonparametric statistics and Monte Carlo method, revealed that there were no executive differences between both groups of offenders but, when compared with non-offenders, the recidivists showed a worse performance in Trail Making Test part B, and the primary offenders presented a significant lower score on Porteus Maze Test Age score. This study suggests that there can be a different pattern of executive functioning deficits associated with the offenders’ criminal record: recidivism may be more related to mental flexibility impairments and primary offenders’ antisocial behaviour may be aggravated by planning deficits.  相似文献   
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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   
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This study analyses depressed fractures (by blunt force trauma) and circular full‐thickness injuries (drill injuries and gunshot wounds) in charred bones. Fifty bovine ribs (total 104 lesions) were divided into three groups. The first group consisted in 20 depressed hammer‐produced fractures; in the second one, 60 round drill‐holes were produced (30 circular, 30 semicircular); in the third group, 12 fleshed and 12 skeletonized ribs were hit by 9‐mm bullets. Each specimen was carbonized in an electric oven up to 800°C. Morphological and metric analyses were performed before and after: morphological features were preserved, but depressed fractures showed an increase in their dimensions (p‐value < 0.05); the drilled holes shrunk (p‐value < 0.01); the charring cycle increased the number of fractures in samples with gunshot wounds differently in fleshed and defleshed ribs. This study showed the complex behavior of charred bone, for what concerns the interpretation of trauma and how caution should be applied.  相似文献   
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As developing democracies implement programs of economic adjustment and trade liberalization, we need to examine the relationship between the state and society in the making of foreign economic policies. This article examines trade and development policies in Colombia, one of Latin America's more institutionalized democracies. Colombia was one of the first countries in Latin America to begin a major reorientation away from full dependence on ISI as a strategy of development. The research shows that domestic political institutions and actors have had a decisive impact on the character and direction of foreign economic policies. The study also illustrates how state capacity for economic management is enhanced by bureaucratic insulation and institutional reform. Carlos E. Juárez is a Ph.D. candidate in the Department of Political Science at the University of California, Los Angeles. His research focuses on the politics of trade liberalization in Latin America, government-business relations in developing democracies, and comparative political economy. He was a visiting researcher and lecturer at theUniversidad de los Andes in Bogotá, Colombia from 1991–1992. For 1993–1994 he will be a visiting research fellow with the Center for U.S.-Mexican Studies at the University of California, San Diego.  相似文献   
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An ethanol-based fixative (FineFIX) has been used, together with rapid microwave-stimulated processing, in postmortem material, resulting in a rapid fixation and processing of the tissues with morphology, histochemical stains, and immunocytochemistry comparable to formalin-fixed material. Furthermore, this alternative fixation gives better DNA recovery in higher amounts if compared with DNA extracted from formalin-fixed tissue, particularly advantageous in forensic pathology.  相似文献   
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