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91.
Sex determination is one of the essential steps in personal identification of an individual from skeletal remains. Most elements of the skeleton have been subjected to discriminant function analysis for sex estimation, but little work has been done in terms of the patella. This paper proposes a new sex determination method from the patella using a novel automated feature extraction technique. A dataset of 228 patellae (95 females and 133 males) was amassed from the William M. Bass Donated Skeletal Collection from the University of Tennessee and was subjected to noninvasive high resolution computed tomography (CT). After the CT data were segmented, a set of features was automatically extracted, normalized, and ranked. The segmentation process with surface smoothing minimizes the noise from enthesophytes and ultimately allows our methods to distinguish variations in patellar morphology. These features include geometric features, moments, principal axes, and principal components. A feature vector of dimension 45 for each subject was then constructed. A set of statistical and supervised neural network classification methods were used to classify the sex of the patellar feature vectors. Nonlinear classifiers such as neural networks have been used in previous research to analyze several medical diagnosis problems, including quantitative tissue characterization and automated chromosome classification. In this paper, different classification methods were compared. Classification success ranged from 83.77% average classification rate using labels from a Fuzzy C-Means (FCM) clustering step, to 90.3% for linear discriminant classification (LDC). We obtained results of 96.02% and 93.51% training and testing classification rates, respectively, using feed-forward backpropagation neural networks (NN). These promising results using newly developed features and the application of nonlinear classifiers encourage the usage of these methods in forensic anthropology for identifying the sex of an individual from incomplete skeletons retaining at least one patella.  相似文献   
92.
In 1999, public defender (PD) representation of defendants appearing before Israel's juvenile courts began to be phased in. This article reports some of the major findings of a study that examined the impacts of the introduction of PDs. Analysis of interviews with 14 PDs yielded four major themes concerning the impact of the "arrival" of PDs, nature of the court, PDs' role, and PDs' interactions with other court actors. Analysis of interviews with eight prosecutors yielded seven themes concerning the need for PDs, PD as state agent, PDs' role, harms of legalization, disruption of the court, compromising the therapeutic value of the court hearing, and changes in court process. More generally, both PDs and prosecutors placed uncritical store in the value of rehabilitation alternatives. Indeed, the welfare model continues to shape their roles. The findings can largely be explained in terms of Eisenstein and Jacob's courtroom workgroup model.  相似文献   
93.
We describe two short amplicon autosomal short tandem repeat (miniSTR) quadruplex systems for eight loci D1S1171, D2S1242, D3S1545, D4S2366, D12S391, D16S3253, D20S161, and D21S1437, unlinked from the combined DNA index system (non-CODIS) loci, using newly designed primer sets. The results of an assay of 411 Japanese individuals showed that polymerase chain reaction (PCR) products within the eight loci were less than 150bp in size, without the seven additional bases for adenylation. The frequency distributions in the loci showed no deviations from Hardy-Weinberg equilibrium expectations. The accumulated power of discrimination and power of exclusion for the eight loci were 0.9999999991 and 0.998, respectively. For assay of highly degraded DNA, including artificially degraded samples and the degraded forensic casework samples assessed with the present miniSTR quadruplex systems, the systems proved quite effective in analyzing degraded DNA.  相似文献   
94.
Seventeen Y-chromosomal short tandem repeats (STRs), DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385ab, DYS437, DYS438, DYS439, GATA-H4, DYS448, DYS456, DYS458, DYS635 were typed in DNA samples from the Kalmyk population (n=99). The population is characterized by a high proportion of duplicated DYS19 alleles and deletions of the locus DYS448 on the background of the Central Asian haplogroup C*. AMOVA analysis reveals a close vicinity to Mongolian and Kazakh populations and large genetic distance to geographical neighbours from Russia, Ukraine and the Caucasus.  相似文献   
95.
Cross-reactivities of 76 kinds of phenethylamine-type designer drugs and related compounds to the urine drug tests Instant-View ? (IV) (the Methamphetamine (MA) test, the Amphetamine 300 test, and the MDMA test) have been investigated. An on-site urine test kit consisting of these three IV tests has been evaluated for the on-site screening of MA users, and the kit has been found to have satisfactory specificity for drug enforcement purposes by separately detecting both MA and its metabolite amphetamine. The cross-reactivity profiles of Emit(?) II Plus Amphetamines Assay, Emit(?) II Plus Ecstasy assay, and Emit(?) d.a.u.(?) Amphetamine Class assay have also been investigated and discussed.  相似文献   
96.
Three-dimensional pelvic images were reconstructed from multi-slice CT data of contemporary Japanese (males: 124; females: 104, 25-92 years old), and curvature analysis to examine sexual dimorphism was carried out in the great sciatic notch (GSN), the pubic arch and the greater pelvis in the images. Reconstructed pelvic CT images were visualized fairly well and anatomical landmarks were easily recognizable. When calculating the radii (curvature radii) of the best-fit circles for the spline curve lines set along the edges of the GSNs and of the pubic arches, sexes from these regions were correctly identified in 89.1% (males: 93.8%; females: 83.7%) and 94.7% (males: 97.3%; females: 91.8%) of cases, respectively, by setting an appropriate cut-off value. Furthermore, sexing was possible even in deeper regions of the GSN which are relatively resistant to postmortem damage. Curvature radii of the best-fit spheres of greater pelves showed no significant difference between sexes. However, curvature of the best-fit sphere for the left iliac fossa was significantly larger than that of the right one (p<10(-24)) in males, and the ratios were >1.0 in 88% of all male specimens analyzed. Meanwhile, no significant difference was observed among female samples. Although some left-sided dominancy has been reported in 2-dimensional measurements of the human pelvis, this 3-dimensional laterality in males was much more significant, and is a potential index of sex difference.  相似文献   
97.
The authors present the case of a 14-year-old boy who died while handling a crossbow, which was a gift from a friend's mother. The bolt passed through the right nostril, penetrated the sinus sphenoidalis, the brain stem, the left occipital lobe and the occipital calvaria. Immediately after the accident, the victim was taken to a maximum care hospital. In spite of neurosurgical treatment and intensive care the victim died 4 days later. The case presented demonstrates that crossbows are not suitable as toys for underage persons, as they are deadly weapons which can cause serious penetrating injuries. In Germany, no license is required to buy and/or possess crossbows. In the authors' opinion, legal restrictions on the sale of crossbows and a special training of the users would be reasonable measures to reduce such accidents.  相似文献   
98.
The external post-mortem examination, its deficient quality and possible causes have been the subject of numerous political and professional discussions. The external post-mortem examination is the basis for the decision whether further criminal investigations are required to clarify the cause of death. It is thus an essential instrument to ensure legal certainty. Before cremation, a second external post-mortem examination is performed by a public medical officer to make sure that errors of the first post-mortem are corrected. In the present study, cases were retrospectively analyzed in which a forensic autopsy had been ordered on the basis of the results of the post-mortem examination performed before cremation. The entries on the death certificate regarding the manner and cause of death were compared with the autopsy results. Between 1998 and 2007, 387 autopsies were ordered after external examination before cremation. In 55 cases (14.2%), the autopsy revealed a non-natural death, although a natural death had been attested on the death certificate. In descending order, a wrong manner of death was attested by clinicians, general practitioners and emergency physicians. With regard to the place where the first external post-mortem had been performed the lowest error rate was seen in nursing homes. Concerning the cause of death, discrepancies between the first post-mortem and autopsy were found in 59.4% of the cases. In this respect, general practitioners and clinicians were ranking first, whereas in nursing homes the cause of death was wrongly assessed in over 70% of cases. At present, the medical post-mortem does not meet the required quality standards, especially with regard to legal certainty. Determination of the cause of death on the basis of the external post-mortem examination is a challenging task even for the experienced medical examiner. As to the categorization of the manner of death it has to be stated that non-natural deaths are often not recognized or that the possibility to certify a death as unclear is not sufficiently used. As a result, it seems important to demand intensive, qualified, additional training in external post-mortem examinations for physicians.  相似文献   
99.
This paper extends previous research and discussion on the use of multivariate continuous data, which are about to become more prevalent in forensic science. As an illustrative example, attention is drawn here on the area of comparative handwriting examinations. Multivariate continuous data can be obtained in this field by analysing the contour shape of loop characters through Fourier analysis. This methodology, based on existing research in this area, allows one describe in detail the morphology of character contours throughout a set of variables. This paper uses data collected from female and male writers to conduct a comparative analysis of likelihood ratio based evidence assessment procedures in both, evaluative and investigative proceedings. While the use of likelihood ratios in the former situation is now rather well established (typically, in order to discriminate between propositions of authorship of a given individual versus another, unknown individual), focus on the investigative setting still remains rather beyond considerations in practice. This paper seeks to highlight that investigative settings, too, can represent an area of application for which the likelihood ratio can offer a logical support. As an example, the inference of gender of the writer of an incriminated handwritten text is forwarded, analysed and discussed in this paper. The more general viewpoint according to which likelihood ratio analyses can be helpful for investigative proceedings is supported here through various simulations. These offer a characterisation of the robustness of the proposed likelihood ratio methodology.  相似文献   
100.
The burial of a body can affect plant communities through mechanical disturbance and nutrient balance alteration. We performed an experimental trial using five swine carcasses buried in an open site in Italy. Vegetation dynamics was monitored recording monthly every plant individual on a regular sampling grid during 1 year on the graves, on an empty control grave, and on an undisturbed plot. Plant species composition and cover were significantly different between the disturbed and the undisturbed plots. Disturbed plots showed the increase in ruderal species and the reduction in stress-tolerant ones. Graves and the control grave could not be distinguished from each other. Disturbance was the main factor affecting plant cover, while the presence of a buried body did not affect vegetation dynamics. However, disturbance could be easily detected; the functional approach seems promising for the identification of dynamic patterns to be used in different biogeographic and ecological contexts.  相似文献   
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