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51.
A qualitative and quantitative analytical method was developed and validated for the determination of 49 licit and illicit drugs in oral fluid. Small oral fluid samples, volume 1mL, were collected from volunteers using a modified Omni-Sal device and the analytes were extracted from an oral fluid/buffer mixture using a single Bond Elut Certify solid phase extraction cartridge. Liquid chromatography-tandem mass spectrometry (LC-MS-MS) and gas chromatography-repetitive full scan mass spectrometry (GC-MS) were used in parallel to analyze the extracts for the targeted drugs. Extracts were analyzed by GC-MS in their underivatized form and as their pentafluoropropionyl derivatives. Deuterated internal standards were used for quantification of drugs of abuse by LC-MS-MS to minimize matrix effects. Methadone-d(9) and tumoxetine were used as the internal standards for quantification of non-derivatized and derivatized analytes respectively by GC-MS. Linearity was demonstrated over the range 5-200 ng/mL and limits of detection were less than 4 ng/mL for each drug analyzed. The method demonstrated acceptable recoveries for most of the analytes and good intra- and inter-day precision. Acquisition of data by repetitive full scan GC-MS allows the addition of further analytes to the target menu.  相似文献   
52.
Degradation of human DNA extracted from forensic stains is, in most cases, the result of a natural process due to the exposure of the stain samples to the environment. Experiences with degraded DNA from casework samples show that every sample may exhibit different properties in this respect, and that it is difficult to systematically assess the performance of routinely used typing systems for the analysis of degraded DNA samples. Using a batch of artificially degraded DNA with an average fragment size of approx. 200 bp a collaborative exercise was carried out among 38 forensic laboratories from 17 European countries. The results were assessed according to correct allele detection, peak height and balance as well as the occurrence of artefacts. A number of common problems were identified based on these results such as strong peak imbalance in heterozygous genotypes for the larger short tandem repeat (STR) fragments after increased PCR cycle numbers, artefact signals and allelic drop-out. Based on the observations, strategies are discussed to overcome these problems. The strategies include careful balancing of the amount of template DNA and the PCR cycle numbers, the reaction volume and the amount of Taq polymerase. Furthermore, a careful evaluation of the results of the fragment analysis and of automated allele calling is necessary to identify the correct alleles and avoid artefacts.  相似文献   
53.
This study investigated deliberate self-harm (DSH) in young inmates. The objectives are twofold: first, to identify the social and clinical characteristics of inmates who commit DSH; and secondly, to ascertain the types of personality who are vulnerable in order to be able to predict future inmates who may harm themselves. A cross-sectional design was used to study psychosocial correctional personality characteristics and clinical pictures in inmates with DSH versus a control group without DSH. The measures used to evaluate different variables were a standard protocol and a self-report questionnaire (MCMI-II). Although the two groups compared are homogeneous and similar in terms of different psychosocial variables, inmates with DSH presented a significant background of maltreatment. Borderline, passive-aggressive, and antisocial personality disorders best discriminated both groups. The detection of borderline, negativistic, and antisocial disorders may help the medical services of penitentiary centers to predict youths with a possible risk of DSH. Despite the results obtained, longitudinal studies are needed to help clarify other risk factors, as well as other risk factors leading to self-harm behavior.  相似文献   
54.
Interpretation of postmortem change in cadavers in Spain   总被引:2,自引:0,他引:2  
Estimating time since death is especially difficult in the examination of poorly preserved cadavers and depends on the experience of the examiner and comparison with previously documented cases showing similar characteristics. The present study reports on information obtained over the past ten years through the work of the Laboratorio de Antropología y Odontología Forense (LAF) of the Instituto Anatómico Forense de Madrid, Spain, in particular evaluating how the type of fracture influences postmortem change. From the original 225 forensic cases examined between 1992 and 2002 in the LAF, a sample of 29 cases were selected from various regions of the Spanish mainland. A data collection protocol was established to reflect factors which the existing specialized literature, documenting the relation existing in the sample analyzed between time since death and the extent of postmortem change, which in the environments examined are distributed into the following phases: Phase 1 (putrefaction): one week to one month on the surface and two months in water. Phase 2 (initial skeletonization): two months on the surface and five to six months in water. Phase 3 (advanced skeltonization): six months to 1.5 years on the surface and 2.5 years buried. Phase 4 (complete skeletonization): about one year on the surface and three years buried. This paper also provide useful information on the impact of carrion insect activity, location, climate, seasonality, and predator.  相似文献   
55.
Allele frequencies for 16 short tandem repeats (STR) loci were determined with a sample of 230-300 unrelated individuals from the population of Rio de Janeiro, Brazil. The loci are the most commonly used in forensic and paternity testing, being analysed by the Identifiler (Applied Biosystems) and PowerPlex 2.1 (Promega) commercial kits. It was proved that Penta E and D18S51 are the most polymorphic loci.  相似文献   
56.
Genotype polymorphism studies at the 13 loci STRs included in the combined DNA index system [CODIS and PCR-based short tandem repeat loci, in: Proceedings of the Second European Symposium on Human Identification, Promega Corporation, Madison, WI, 1998, pp. 73-88; J. Forensic Sci. 46 (2001) 453] (CODIS: D3S1358, HUMvWA31, HUMFGA, D8S1179 D21S11, D18S51, D5S818, D13S317, D7S820, HUMTH01, HUMTPOX, HUMCSF1PO and D16S539) were carried out in a sample of 1429 unrelated Colombian individuals belonging to 25 different departments. As many other countries in Latino-America, Colombia shows an important admixture component, basically integrated by Amerindians, European-descendants and African-descendants. Due to the fact that only partial population analyses have been carried out in the country, the main aim of the present analysis is to establish a database of forensic interest based on the widely used CODIS systems covering the main Colombian regions.  相似文献   
57.
Allele frequencies for the 15 autosomic STR loci included in the PowerPlex 16 System kit (Promega Corp.) were estimated from a sample of 143 unrelated individuals living in Capital Federal and in Buenos Aires Metropolitan Area, Argentina. Population showed to be in HWE.  相似文献   
58.
Three hundred and twenty-six to four hundred and fifty-one individuals were typed for 12 STR markers and revealed by silver stain method and assisted by a computer analysis. Forensic and Hardy-Weinberg values were found. The Kodak ds 1D Image Analysis Software V 2.0.3 EDAS DC 120 System was a useful tool for determining the correct size of pattern bands that were out allelic ladders, alleles 18 and 17 from F13A01, 15 from TPOX and 4 from TH01 were determined by this method and some corroborated by automatic analysis.  相似文献   
59.
Allele frequencies for 09 STR autosomal loci (D3S1358, D5S818, D7S820, D8S1179, D13S317, D18S51, D21S11, FGA and VWA) included in the AmpFlSTR Profiler Plus were obtained from a sample of unrelated individuals from Rio Grande do Sul (southern Brazil).  相似文献   
60.
In this article, we present a model of individual dismissals based on the workers' right to file a suit against their employer arguing that the dismissal is unjustified or unfair. The model is a standard pre-trial bargaining game between a firm and a worker. We study two cases: when the law states the severance pay for unfair dismissal (the European case), and when judges can decide freely on the compensation to be paid to the worker (the American case). The model provides some guidelines for Labour Law reforms. In the European case, a decrease in the severance pay for unfair dismissals fixed by law will decrease the severance pay offered by the firm, and only under some assumptions will decrease the expected firing cost and will increase the settlement probability. In addition, the transition from the European to the American case is likely to increase the probability of settlement (and to decrease it in the opposite case) with ambiguous effects on agreed severance pay and expected firing costs.  相似文献   
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