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991.
The aim of this study was to determine if ancient hair shafts could be suitable for nuclear DNA analysis and to develop an efficient and straightforward protocol for DNA extraction and STR typing of ancient specimens. The developed method was validated on modern and forensic samples and then successfully applied on ancient hairs collected from Siberian mummies dating from the 16th to the early 19th centuries. In parallel extractions including or excluding a washing step were performed at least two times for each sample in order to evaluate the influence on the quantity of nuclear DNA yielded and on the typing efficiency. Twelve ancient individuals were analyzed through our approach and full and reliable profiles were obtained for four of them. These profiles were validated by comparison with those obtained from bone and teeth DNA extracted from the same ancient specimens. The present study demonstrates that the washing step cannot be considered as deleterious for DNA retrieval since the same results were obtained by the two approaches. This finding challenges the hypothesis that recoverable nuclear DNA is only found on the outer surface of hair shafts and provides evidence that nuclear DNA can be successfully extracted from ancient hair shafts. The method described here constitutes a promising way for non-invasive investigations in ancient DNA analysis for precious or historical samples as well as forensic casework analyses.  相似文献   
992.
Pattern recognition techniques can be very useful in forensic sciences to point out to relevant sets of events and potentially encourage an intelligence-led style of policing. In this study, these techniques have been applied to categorical data corresponding to cutting agents found in heroin seizures. An application of graph theoretic methods has been performed, in order to highlight the possible relationships between the location of seizures and co-occurrences of particular heroin cutting agents. An analysis of the co-occurrences to establish several main combinations has been done. Results illustrate the practical potential of mathematical models in forensic data analysis.  相似文献   
993.
Establishing a person's identity can be a very difficult process. Dental, fingerprint and DNA comparisons are probably the most common techniques used in this context, allowing fast and secure identification processes. However, since they cannot always be used, sometimes it is necessary to apply different and less known techniques. In this paper, the authors describe two unusual techniques: cheiloscopy and palatoscopy. It is known that due to their special features, both lip grooves and palatal rugae can be used successfully in human identification. This paper reviews the techniques of cheiloscopy and palatoscopy, and describes the different classifications and their advantages and limitations.  相似文献   
994.
Eight Y chromosome short tandem repeats (STR) loci (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385I/II) were used to assess haplotype distribution in non-selected, unrelated Bantu males living in Central Africa [N. Mathias, M. Bayes, C. Tyler-Smith, Highly informative compound haplotypes for the human Y chromosome, Hum. Mol. Genet. 3 (1994) 115-123; L. Roewer, J. Arnemann, N.K. Spurr, K.H. Grzeschik, J.T. Epplen, Simple repeat sequences on the human Y chromosome are equally polymorphic as their autosomal counterparts, Hum. Genet. 89 (1992) 389-394; P. De Knijff, M. Kayser, A. Caglia, D. Corach, N. Fretwel, C. Gehrig, G. Graziosi, F. Heidorn, S. Herrmann, B. Herzog, M. Hidding, K. Honda, M. Jobling, M. Krawczak, K. Leim, S. Meuser, E. Meyer, W. Oesterreich, A. Pandya, W. Parson, G. Penacino, A. Perez-Lezaun, A. Piccini, M. Prinz, C. Schmitt, P. M. Schneider, R. Szibor, J. Teifel-Greding, G. Weishold, L. Rower, Chromosome Y microsatellites: population genetic and evolutionary aspects, Int. J. Legal Med. 110 (1997) 134-149; M. Kayser, A. Caglia, D. Corach, N. Fretwel, C. Gehrig, G. Graziosi, F. Heidorn, S. Herrmann, B. Herzog, M. Hidding, K. Honda, M. Jobling, M. Krawczak, K. Leim, S. Meuser, E. Meyer, W. Oesterreich, A. Pandya, W. Parson, G. Penacino, A. Perez-Lezaun, A. Piccini, M. Prinz, C. Schmitt, P. M. Schneider, R. Szibor, J. Teifel-Greding, G. Weishold, P. de Knijff, L. Rower, Evaluation of Y chromosome STRs: a multicenter study, Int. J. Legal Med. 110 (1997) 125-133, 141-149]. One hundred and sixty-five full haplotypes were obtained from Bantu males. The most common haplotype (DYS19-15, DYS389I-13, DYS389II-30, DYS390-21, DYS391-10, DYS392-11, DYS393-13, DYS385I/II-15,17) was shared by 5.5% of individuals. In the Bantu population in Central Africa, the haplotype diversity and the discrimination capacity of Y-STR may be estimated at 99.14% and 0.5333, respectively.  相似文献   
995.
Allele frequencies and forensic parameters for six miniSTR autosomal loci (D10S1248, D14S1434, D22S1045, D4S2364, D2S441 and D1S1677) were obtained from a sample of 264 unrelated individuals from Spain. No significant deviations from Hardy-Weinberg expectations were found. Due to the small PCR products (<125 bp), the use of these non-CODIS (NC) miniSTRs can increase the probability that a degraded sample can be typed. Additionally, these systems can be used in routine paternity analyses where more markers are needed to increase the power of exclusion or in complex paternity cases (e.g. involving closely related individuals).  相似文献   
996.
This study expands our knowledge about the validity of self-reported drug use by examining how gender, race, age, type of drug, and offense seriousness interact to affect the validity of self-reported drug use. This study also provides a conceptual framework that can be used to examine the validity of self-reported drug use. Differences in the validity of self-reported drug use are explained by examining differences in underreporting and overreporting. Differences in underreporting and overreporting are then further examined while controlling for differences in base rates of drug use. As shown, whether one controls for base rates of use may drastically affect estimates of underreporting and overreporting. By using hierarchical loglinear, logit, and logistic regression models with the Drug Use Forecasting data, we show that Black offenders provide less accurate self-reports than White offenders. Black offenders do so because they are more likely to underreport crack/cocaine use than White offenders. This difference, however, disappears once differences in base rates are controlled. A Black offender who tests positive is not more likely to underreport crack/cocaine use than a White offender who tests positive. Black offenders are also more likely to overreport both marijuana and crack/cocaine use relative to White offenders. Contrary to the first, this difference is not attributable to a difference in base rates. Methodological and substantive implications of this distinction are discussed. No differences across gender, age, or offense seriousness were found.
André B. RosayEmail:
  相似文献   
997.
The mitochondrial DNA (mtDNA) working group of the GEP-ISFG (Spanish and Portuguese Group of the International Society for Forensic Genetics) carried out an inter-laboratory exercise consisting of the analysis of mtDNA sequencing patterns in mixed stains (saliva/semen and blood/semen). Mixtures were prepared with saliva or blood from a female donor and three different semen dilutions (pure, 1:10 and 1:20) in order to simulate forensic casework. All labs extracted the DNA by preferential lysis and amplified and sequenced the first mtDNA hypervariable region (HVS-I). Autosomal and Y-STR markers were also analysed in order to compare nuclear and mitochondrial results from the same DNA extracts. A mixed stain prepared using semen from a vasectomized individual was also analysed. The results were reasonably consistent among labs for the first fractions but not for the second ones, for which some laboratories reported contamination problems. In the first fractions, both the female and male haplotypes were generally detected in those samples prepared with undiluted semen. In contrast, most of the mixtures prepared with diluted semen only yielded the female haplotype, suggesting that the mtDNA copy number per cell is smaller in semen than in saliva or blood. Although the detection level of the male component decreased in accordance with the degree of semen dilution, it was found that the loss of signal was not consistently uniform throughout each electropherogram. Moreover, differences between mixtures prepared from different donors and different body fluids were also observed. We conclude that the particular characteristics of each mixed stain can deeply influence the interpretation of the mtDNA evidence in forensic mixtures (leading in some cases to false exclusions). In this sense, the implementation of preliminary tests with the aim of identifying the fluids involved in the mixture is an essential tool. In addition, in order to prevent incorrect conclusions in the interpretation of electropherograms we strongly recommend: (i) the use of additional sequencing primers to confirm the sequencing results and (ii) interpreting the results to the light of the phylogenetic perspective.  相似文献   
998.
The purpose of this study was to identify sociodemographic, contextual, situational, and individual variables, as well as certain behavioral warning signs, associated with filicide as a function of sex of the agressors and the presence or absence of self-destructive behaviours. The data cover all officially registered filicides committed in Quebec from January 1, 1986, to March 31, 1994, against youths under the age of 18 years. For the group of individuals who have self-destructive behaviours, results indicate that men compared to women are more likely to commit spousal homicide, to kill a higher number of victims, to be going through a conjugal separation, to have committed conjugal violence, to have threatened suicide, and to have threatened to kill their spouse. For the group of individuals who commit no self-destructive acts, women are more likely to present with a depressive disorder, whereas men are more likely to maltreated their children. Men who do not commit a self-destructive act are characterized by a significantly higher likelihood of maltreatment against their children and of tyrannical discipline, whereas men who commit a self-destructive act perpetrate filicide as a means of reprisal against their spouse. Results underscore the importance of considering the different groups of individuals who commit filicide as a function of sex as well as presence or absence of self-destructive behaviour.
Suzanne LéveilléeEmail: Email:
  相似文献   
999.
The main aim is the study of coefficient stability using comparative analyses of Spanish input–output tables of recent decades. We try to provide answers to questions related to the nature and intensity of changes in the production structure, implementing procedures both of a direct nature as well as of an indirect one, following Mesnard’s proposal. We further raise the possibility of forecasting branch evolution by means of demand-driven or supply-driven models, depending on coefficient stability, in accordance with the work of Ranko Bon.
Jesús Sanjuán SolísEmail:
  相似文献   
1000.
In response to a recent article published in this review, we present in this paper, an unusual case of fatal salt water intoxication. In this case, we point out three special features, the type of water ingested, the physiopathologic consequences of the ingestion and the very strange context of occurrence. This complex case allows us to point out complications due to salt poisoning and others caused by water intoxication.  相似文献   
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