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131.
Casiano Manrique de Lara Peñate Dolores Santos Peñate 《Economic Change and Restructuring》2003,36(3):259-272
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
132.
Luiz Antonio Ferreira da Silva Beatriz Jatob Pimentel Dalmo Almeida de Azevedo Eliana Neves Pereira da Silva Simone Silva dos Santos 《Forensic Science International Supplement Series》2002,130(2-3):187-188
The polymorphism of nine STR loci has been studied in a sample of 598 individuals from the population of Alagoas, Northeastern Brazil. Determination of the allele frequencies as well as of several commonly used statistics in forensic and paternity testing were defined. The most polymorphic loci were TH01 and D7S317. The exact test demonstrated that the nine loci analyzed in the population have no deviation from Hardy–Weinberg equilibrium (P>0.05). 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
138.
Nondestructive Methods for Recovery of Biological Material from Human Teeth for DNA Extraction
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Montserrat Hervella Ph.D. Maitane G. Iñiguez M.Sc. Neskuts Izagirre Ph.D. Alberto Anta Ph.D. Concepción de‐la‐Rúa Ph.D. 《Journal of forensic sciences》2015,60(1):136-141
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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