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961.
Previous studies suggest that palate shape is a useful indicator of biological ancestry in human remains. This study evaluates interobserver error in ancestry estimation using palate shape and explores palate shape variation in Gullah (descendants of West Africans) and Seminole (Indigenous American) population samples using geometric morphometric analysis. Ten participants were asked to ascribe biological ancestry and shape to 28 dental casts based on a classification scheme employed in previous studies. The mean correct classification was 42.0%, indicating that the likelihood of assigning the correct ancestry is very poor and not significantly different from random assignment (= 0.12). The accuracy analysis based on categorical classification of the casts was complemented by geometric morphometric analysis of nine 3D landmarks reflecting palate shape of 158 casts. Principal component analysis results show no difference between populations regarding palate shape, and cross‐validated discriminant function analysis correctly classified only 62.0% of the specimens. Combined, these results show that previous methods to estimate ancestry are inaccurate and that this inaccuracy is probably due to a lack of palate shape differences between groups, rather than limitation of the analytical method per se. Therefore, we recommend caution should be used when choosing to apply the analysis of palate shape in forensically relevant contexts.  相似文献   
962.
Experiments were performed to determine the extent of cross‐contamination of DNA resulting from secondary transfer due to fingerprint brushes used on multiple items of evidence. Analysis of both standard and low copy number (LCN) STR was performed. Two different procedures were used to enhance sensitivity, post‐PCR cleanup and increased cycle number. Under standard STR typing procedures, some additional alleles were produced that were not present in the controls or blanks; however, there was insufficient data to include the contaminant donor as a contributor. Inclusion of the contaminant donor did occur for one sample using post‐PCR cleanup. Detection of the contaminant donor occurred for every replicate of the 31 cycle amplifications; however, using LCN interpretation recommendations for consensus profiles, only one sample would include the contaminant donor. Our results indicate that detection of secondary transfer of DNA can occur through fingerprint brush contamination and is enhanced using LCN‐DNA methods.  相似文献   
963.
Pulmonary polymethylmethacrylate (PMMA) cement embolism after kyphoplasty (KP) surgery is a quite frequent event as well as the pulmonary embolization of central venous catheter fragment. This report shows the case of a subject who, after KP, developed pulmonary embolism and who underwent thoracic surgery. After hospital discharge, the subject advanced a claim for damages toward the hospital where he was operated, complaining sensation of tenderness at the chest surgical scar and esthetic damage. To understand the nature of the embolism (either central venous catheter fragment or cement), chemical investigations were then ordered. Spectrometry identified the PMMA cement used for KP. When doubts rise about the origin of the embolized material, chemical investigations may reveal important data not only for clinical but also for forensic purposes.  相似文献   
964.
The AmpF?STR Yfiler PCR Amplification (Yfiler) kit continues to be improved for a better analytical efficiency in cases of highly degraded DNA. The authors endeavored to determine whether coupling of the Yfiler kit with supplemental multiplex amplification of some Y‐STR loci is a more efficient analytical mode for poorly preserved human femurs (n = 15) discovered at Korean archeological sites. To reveal locus profiles not easily obtained by Yfiler analysis, custom‐designed primers were adopted for the DYS390, DYS391, DYS392, DYS438, DYS439, and DYS635 loci. The success rate for 16 Y‐STR locus profiles obtained from the 15 femurs was improved from 18.33% (in the use of Yfiler kit only) to 49.17% (the coupled use of Yfiler and custom‐designed primers). In this study, the authors established that the custom‐designed primers offer a markedly improved success rate for obtainment of Y‐STR profiles from degraded aDNA not easily identified by sole use of the Yfiler assay.  相似文献   
965.
This study applied a decision‐making perspective to examine the causal mechanisms underlying the relation between violent victimization and offending. We theorized that having been victimized affects an individual's appraisal of subsequent potentially conflictive situations in such a way that victims become more attuned toward the benefits of violence perpetration than toward its costs. Furthermore, we argued that this altered appraisal mediates the relation between violent victimization and violent offending. We tested these hypotheses by using data from the Zurich Project on the Social Development of Children and Youths, a longitudinal study of Swiss youth (N = 1,013; 11–15 years of age). In line with expectations, path analysis results showed that prior victimization influenced the appraisal of decision‐making situations that, in turn, predicted subsequent self‐reported violent offending. Importantly, these mediation effects held when controlling for a variety of time‐stable factors, such as self‐control and risky activities, as well as prior victimization and delinquency. Implications for research and theorizing on the victim–offender overlap are elaborated in the discussion.  相似文献   
966.
Death from hypothermia following exhaustion or from various complicated pathologies is no longer a frequent cause of death among combat troops. During a training course under “extreme conditions” in the French Alps, two young African officers died. Confronted with these two clinically confirmed cases of hypothermia, the unknown anatomopathological and biological specificities associated with death from hypothermia were highlighted. In these typical and clinically confirmed cases of death from subacute exhaustion hypothermia, none of the signs revealed by the autopsy were specific. Although some recent publications have addressed the utility of postmortem biochemical markers when establishing a diagnosis, with no anamnesis, with no knowledge or analysis of the circumstances of death, and without an in situ examination of the body, it appears difficult, if not impossible, to confirm that death was caused by hypothermia.  相似文献   
967.
The interpretation of complex DNA profiles is facilitated by a Bayesian approach. This approach requires the development of a pair of propositions: one aligned to the prosecution case and one to the defense case. This note explores the issue of proposition setting in an adversarial environment by a series of examples. A set of guidelines generalize how to formulate propositions when there is a single person of interest and when there are multiple individuals of interest. Additional explanations cover how to handle multiple defense propositions, relatives, and the transition from subsource level to activity level propositions. The propositions depend on case information and the allegations of each of the parties. The prosecution proposition is usually known. The authors suggest that a sensible proposition is selected for the defense that is consistent with their stance, if available, and consistent with a realistic defense if their position is not known.  相似文献   
968.
To understand the mortality patterns among drug users and potential risk factors, we evaluated drug‐related deaths reported to the Florida Medical Examiners Commission from 2001 to 2013, by substances, demographics, and manner of death. The annual drug‐related fatalities increased by 57% from 2001 to 2013 (total n = 100,882); 51.8% were accidental, 7.9% homicide, 18.6% natural, and 19.6% suicide. The different manners of death exhibited distinct demographic profiles and drug composition. The gender gap was more prominent in homicide. Age ≥55 years was more closely associated with natural death and suicide. Age <35 years and central nervous system (CNS) stimulants including amphetamines and cocaine showed higher relative risks for accidental death and homicide, whereas CNS depressants including benzodiazepines, carisoprodol, opioids, and zolpidem were more strongly associated with accidental death and/or suicide. The findings aid in identifying populations more vulnerable to drug‐related deaths, developing targeted interventions and thereby improving efficiency of preventive efforts.  相似文献   
969.
Forensic laboratories are often faced with cases in which methamphetamine hydrochloride‐mixed blood is unable to be identified as human blood by immunochromatography against human hemoglobin A0. The application of mRNA expression analysis to samples that showed a false‐negative with immunochromatography was investigated as an alternative approach that did not depend on the antigen–antibody reaction. Real‐time PCR was used to examine the expression levels of blood markers such as glycophorin A, spectrin beta, and hemoglobin beta. Hemoglobin beta was the only marker that was specifically detected in blood, while glycophorin A was useful for determining human specificity. Hemoglobin beta showed good detection sensitivity and was detectable in 37‐year‐old blood stains. Hemoglobin beta was exclusively detectable in methamphetamine hydrochloride‐mixed blood stains. Detergents and disinfectants did not significantly influence mRNA markers. The proposed mRNA expression analysis was suitable for human blood identification as an alternative method to immunochromatography.  相似文献   
970.
Wound age estimation is one of the most important forensic aspects. Troponin I (TnI) and many cytokines, for example, tissue plasminogen activator (tPA), are involved in wound inflammation and healing. Skeletal (TnI) and cutaneous (tPA) mRNA was detected using real‐time PCR in 25 female albino rats. They were divided into 5 groups: control and 4 injured groups. Injured groups were sacrificed 1, 6, 24, and 30 h after inflicting contused wound. The expression levels of cutaneous (tPA) were decreased significantly at 1, 6, and 30 h after contusion (71.7%, 30.7 and 16.9%), while the expression levels of skeletal (TnI) were increased significantly at 1 and 6 h post‐traumatic, then they gradually decreased until reaching normal levels at 24 h and assumed significantly lower levels at 30 h postcontusion. These results suggested that the determination of cutaneous (tPA) and skeletal (TnI) mRNA levels was useful for wound age estimation.  相似文献   
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