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31.
Many structural relationships should be taken into account in any reasonable adjustment and updating process. These structural relationships are mainly represented by ratios of different types, such as technical coefficients or the proportion of the cell value in relation to its row or column total. We believe that in many cases (either because of lack of information or when the time elapsed for the estimation of a social accounting matrix is not long enough to allow for any significant structural change) the updating process should try to minimize the rela- tive deviation of the new coefficients from the initial ones in a homogeneous way. This homogeneity would mean that the magnitude of this relative deviation is similar among the elements of each row or column, therefore avoiding the concentration of the changes in particular cells of the SAM. In this work, we propose some new adjustment criteria in order to obtain a more homogeneous relative adjustment of the structural coefficients. These criteria combine the adjustment method proposed by Matuszewski et al. (1964) with other deviation functions. Each of the adjustment criteria proposed leads to a nonlinear optimization problem which is reformulated as a linear program. We test the usefulness of this proposal by comparing its results with the ones obtained by more standard approaches and we are able to show that these approaches tend to produce a less homogeneous pattern of coefficient adjustment, under certain circumstances, than the ones we put forward.  相似文献   
32.
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   
33.
This article analyses political attitudes to the union in England, Scotland and Wales after the Scottish independence referendum. Using public opinion data, we explore constitutional preferences and perceptions of national grievance, before examining the role that national identity plays in structuring preferences. Our evidence shows that considerable demand exists for nationally demarcated forms of government within the UK, although these constitutional preferences do not translate in support for policy diversity across the UK. We also find evidence that these constitutional preferences relate closely to national identity, but relate also to appeals to national interest.  相似文献   
34.
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   
35.
Research into maximizing the speed, precision, and reliability of estimating the postmortem interval (PMI) has been a recurring object of investigation and methodologies based on the vitreous humor (VH) have provided good results. However, contamination from causes not readily apparent, such as blood, can occur, and thus lead not only to an erroneous estimation of PMI, but also interfere with the correct identification of other substances in the VH. We have developed a flow cytometry method which quantifies blood contamination and is able to detect erythrocytes in 1:750,000 dilution of contaminated VH which affects the results of hypoxanthine. It is an improvement on the previous more complex mass spectrometry method, being faster, more sensitive, and readily available. As such, it could be proposed for the rapid screening of appropriate samples by detecting and eliminating blood contaminated samples from PMI estimation.  相似文献   
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International networks for social change are growing in number and influence. While they need to be able to assess the extent to which they achieve their purpose and determine ways in which to be more effective, conventional evaluation methods are not designed for such complex organisational forms, or for the diverse kinds of activity to which they are characteristically dedicated. Building on an earlier version of their paper, the authors present a set of principles and participatory approaches that are more appropriate to the task of evaluating such networks.  相似文献   
38.
吴丕 《学习论坛》2006,22(10):78-80
"异端"一词虽然在过去一直是指不符合正统思想的主张或教义,但是在《论语》中最早出现"异端"一词时,它的意思只是指不同意见而已.孔子的真正意思是对于不同意见进行攻击,这样的做法是非常有害的.这样的解释符合孔子的精神,即宽容、博学、和而不同.和而不同就是保持社会和谐,容忍不同意见.  相似文献   
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The average exclusion probability is a measure of efficiency in paternity testing; it refers to the a priori ability of a battery of tests to detect paternity inconsistencies. This parameter measures the capacity of the system to detect a false accusation of paternity. Traditionally, this average exclusion probability has been estimated as the probability of excluding a man who is not the father by an inconsistency in at least one of the studied loci. We suggest that this criterion should be corrected, as currently the presumed father is excluded when at least three genetic inconsistencies are found with the child being tested, not just one. This change of criterion has occurred because of the use of microsatellite loci, whose mutation rates are much greater than those of the coding genes used previously in paternity studies. We propose the use of the average probability of exclusion for at least three loci (not only one), as an honest measure of the combined probability of exclusion of several loci, and we propose an algebraic expression to calculate it.  相似文献   
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