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401.
A.M. Lagoa T. Magalhães M.F. Pinheiro 《Forensic Science International: Genetics Supplement Series》2008,1(1):48-49
In this work we aimed to compare the application of increasing PCR cycle number, whole genome amplification and nested-PCR on fingerprints genetic analysis. Results were compared for correct alleles, allele dropin and allelic dropout. We concluded that increasing the number of PCR cycles is yet the best way to attain the required sensitivity. 相似文献
402.
D.J. French R.L. Howard N. Gale T. Brown D.G. McDowell P.G. Debenham 《Forensic Science International: Genetics Supplement Series》2008,2(4):333-339
Current forensic DNA profiling methods rely on the analysis of samples at specialised laboratories with an average turnaround time of several days. The ability to rapidly determine a partial profile of short tandem repeats at the point-of-arrest would be of great benefit to police forces around the world, for example enabling a suspect to be rapidly included or excluded from an investigation. We have developed a homogeneous PCR method for the interrogation of STR loci utilising fluorescent oligonucleotide probes and melting curve analysis. Alleles of the D18S51, TH01 and D8S1179 loci were differentiated and identified on the basis of target length and probe melting temperature. Assay performance was evaluated by comparing melting peak data with the AmpFlSTR® SGM Plus® system. The method is compatible with direct analysis of unpurified buccal swab samples, enabling a partial STR profile to be generated within 1 h. 相似文献
403.
Correlation among age, concentrations of carboxyhemoglobin and hydrogen cyanide, oxygen density and hemolysis were studied in 120 house fire victims. Victims aged over 60 years comprised approximately 50% of the pooled subjects. Blood samples were mainly collected from the left ventricle, but sometimes from both the right and left ventricles. The concentration of carboxyhemoglobin ranged from 1-95%, of which 71 persons (59.7%) died with carboxyhemoglobin concentrations below 60%. Carboxyhemoglobin concentrations below 10% were found in 9 persons (7.5%). Most of these cases involved the elderly persons. In this paper, we report on the death of elderly victims as a result of low carboxyhemoglobin concentrations. A significant correlation of blood carboxyhemoglobin concentrations existed between the right and left ventricles. The concentration of carboxyhemoglobin in the left ventricle was significantly higher than that in the right. Two out of 31 victims whose hydrogen cyanide concentrations were determined, succumbed to hydrogen cyanide poisoning, having a high concentration of hydrogen cyanide and a low concentration of carboxyhemoglobin. On analysis, oxygen density was found to be low in 13 persons. A negative correlation was shown between carboxyhemoglobin concentration and hemolysis. Inasmuch as hemolysis may indicate the extent of heat dissociation, hemolysis should provide an index of carbon monoxide dissociation from carboxyhemoglobin. In the present study of victims, possible causes of death i.e., carbon monoxide gas poisoning, hydrogen cyanide poisoning, oxygen deprivation, burning, shock due to burns and others were estimated. The survival time for elderly victims was considered to be short. 相似文献
404.
405.
Our goal in this article is to contribute conceptually and empirically to assessments of the racial invariance hypothesis, which posits that structural disadvantage predicts violent crime in the same way for all racial and ethnic groups. Conceptually, we elucidate the scope of the racial invariance hypothesis and clarify the criteria used for evaluating it. Empirically, we use 1999–2001 averaged arrest data from California and New York to extend analyses of the invariance hypothesis within the context of the scope and definitional issues raised in our conceptual framing—most notably by including Hispanic comparisons with Blacks and Whites, by examining the invariance assumption for homicide as well as the violent crime index, by using discrete as well as composite disadvantage measures, and by using census place localities as the study unit. The mixed findings we report from our comparisons (across Whites, Blacks, and Hispanics; offense types; and type of disadvantage) suggest caution and uncertainty about the notion that structural sources of violence affect racial/ethnic groups in uniform ways. We conclude that the hypothesis should be regarded as provisional, and its scope remains to be established as to whether it applies only under narrow conditions or is a principle of general applicability. 相似文献
406.
407.
A simple method was devised to assess dental attrition in terms of its area and number of sites by using dental plaster casts and a computer assisted image analyser. The changes presented on the occlusal surfaces of teeth were investigated for age estimation using these criteria. The area of attrition on each tooth demonstrated a significant positive correlation with age, but a wide individual variation was observed in the values for each tooth. Therefore, this method was unsuitable for accurate age estimation of a single tooth. A strong negative correlation with age was observed in the number of sites of attrition. A multiple stepwise regression analysis using the variables 'attrition area' and 'attrition number' revealed multiple correlation coefficient values of 0.93. The quantitative assessment of both horizontal and vertical factors of dental attrition would be essential to improve the accuracy of this method. 相似文献
408.
409.
The relation between recession and homicide is classic in the United States. This has been affirmed in the 1976 and 1984 Reports to the Joint Economic Committee (JEC) of the United States Congress. Recent analysis confirms the findings reported in both 1976 and 1984 and demonstrates that the influence of recession on homicide is greater than previously estimated. Differences in the 1976 and 1984 findings on homicide are related to differences in the hypotheses tested, as discussed in detail and highlighted in the 1984 report. JEC staff correctly interpreted and reported the 1984 findings. Reproduction of the 1984 homicide equation is straightforward, provided the same data and any of several standard estimation techniques are used. Evidence does not support any of Cook and Zarkin's claims in their critique of the 1984 homicide equation. The JEC report of 1984 used appropriate techniques in the attempt (a) to ensure that influences attributed to economic changes are not actually due to other social factors and (b) to minimize underspecification of models. 相似文献
410.