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11.
Youth who participate in service activities differ from those who do not on a number of key demographic characteristics like socio-economic status and other indicators of risk; and most studies demonstrating positive outcomes among service participants employ small non-representative samples. Thus, there is little evidence as to whether the outcomes associated with service participation are similar among students with varying levels of risk. The National Household Education Survey of 1999, a large nationally representative cross-sectional data set that focused on community service, was analyzed to investigate associations between the risk status of 4,306 adolescent students (50.2% female; 63.3% European American, M age?=?15.9), their participation in community service, and their academic adjustment, behavioral problems, and civic knowledge. Because adolescents who participate in service differ from those who do not with respect to demographic characteristics, propensity score analyses were used to correct for potential selection bias in the examination of these relationships. Analyses tested competing theoretical models of service??protective versus compensatory??among students at varying levels of risk, and suggested that service acts as a compensatory factor with respect to academic, behavioral, and civic outcomes. Propensity score analyses revealed patterns suggesting that, in some cases, students with certain demographic profiles that are themselves related to the likelihood of service participation may benefit from service participation more than others. Findings are discussed in terms of their significance for adolescent development, for planning service programs, and for educational policy. 相似文献
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13.
Barbara Bertoglio M.Sc. Ph.D. Sofia Corradin MS Annalisa Cappella M.Sc. Ph.D. Debora Mazzarelli B.Sc. Lucie Biehler-Gomez M.Sc. Ph.D. Carmelo Messina M.D. Grazia Pozzi M.D. Luca Maria Sconfienza M.D. Ph.D. Francesco Sardanelli M.D. Chiarella Sforza M.D. Ph.D. Danilo De Angelis D.D.S. Ph.D. Cristina Cattaneo M.D. Ph.D. 《Journal of forensic sciences》2020,65(6):2098-2107
Many studies in the literature have highlighted the utility of virtual 3D databanks as a substitute for real skeletal collections and the important application of radiological records in personal identification. However, none have investigated the accuracy of virtual material compared to skeletal remains in nonmetric variant analysis using 3D models. The present study investigates the accuracy of 20 computed tomography (CT) 3D reconstruction models compared to the real crania, focusing on the quality of the reproduction of the real crania and the possibility to detect 29 dental/cranial morphological variations in 3D images. An interobserver analysis was performed to evaluate trait identification, number, position, and shape. Results demonstrate a false bone loss in 3D models in some cranial regions, specifically the maxillary and occipital bones in 85% and 20% of the samples. Additional analyses revealed several difficulties in the detection of cranial nonmetric traits in 3D models, resulting in incorrect identification in circa 70% of the traits. In particular, pitfalls included the detection of erroneous position, error in presence/absence rates, in number, and in shape. The lowest percentages of correct evaluations were found in traits localized in the lateral side of the cranium and for the infraorbital suture, mastoid foramen, and crenulation. The present study highlights important pitfalls in CT scan when compared with the real crania for nonmetric analysis. This may have crucial consequences in cases where 3D databanks are used as a source of reference population data for nonmetric traits and pathologies and during bone-CT comparisons for identification purposes. 相似文献
14.
Sierra F. Kaszubinski B.Sc. Jennifer L. Pechal Ph.D. Carl J. Schmidt M.D. Heather R. Jordan Ph.D. Mark E. Benbow Ph.D. Mariah H. Meek Ph.D. 《Journal of forensic sciences》2020,65(2):513-525
Microbial communities have potential evidential utility for forensic applications. However, bioinformatic analysis of high-throughput sequencing data varies widely among laboratories. These differences can potentially affect microbial community composition and downstream analyses. To illustrate the importance of standardizing methodology, we compared analyses of postmortem microbiome samples using several bioinformatic pipelines, varying minimum library size or minimum number of sequences per sample, and sample size. Using the same input sequence data, we found that three open-source bioinformatic pipelines, MG-RAST, mothur, and QIIME2, had significant differences in relative abundance, alpha-diversity, and beta-diversity, despite the same input data. Increasing minimum library size and sample size increased the number of low-abundant and infrequent taxa detected. Our results show that bioinformatic pipeline and parameter choice affect results in important ways. Given the growing potential application of forensic microbiology to the criminal justice system, continued research on standardizing computational methodology will be important for downstream applications. 相似文献
15.
The necessity of rapid objective appraisal of the suspicion of intracorporeal drug smuggling (body-packing) by effective methods of investigation in the course of the first criminal investigation department measures raises the questions of suitable and admissible methods. The proportion of undetected crimes in intracorporeal narcotic smuggling must be rated as very high according to the data of the Federal Criminal Investigation Department. In the present paper, the suitability of various imaging techniques for drug detection are reported in terms of their risk, practicability and costs. For this purpose, the value of digital radiography, two-spectra radiography and X-ray computer tomography as compared to conventional X-ray investigations is examined in human experiments. A reality-oriented narcotics dummy (glucose pressed hard in preservative) was developed and administered to nine volunteers per os with a variable initial alimentary situation. Four radiograms were taken at fixed times up to 12 hours after administration with each imaging technique. The highest rate of detection was attained with computer tomography. In contrast to the other methods, more than 90% of the body packs could be identified here. Nevertheless, an application in criminal investigation practice cannot be recommended owing to various disadvantages. The recovery rate of the remaining methods is between 20% and 25%. 相似文献
16.
The authors report on a traffic accident in which the passenger of a Light Four-wheeled Vehicle (Microcar) approved for use by a disabled person was killed after a rear collision with a compact car. The severity of the accident trauma was critically determined by the vehicle's light construction. Consideration is also given to the legal situation regarding registration and driver's license issues. 相似文献
17.
Johannes Schmidt 《Politische Vierteljahresschrift》2006,47(1):117-120
18.
Nomination: Does politics matter? A perennial question! by Hans Keman, p.159
Reflections: Politics does indeed matter! by Manfred G. Schmidt, p.164 相似文献
Reflections: Politics does indeed matter! by Manfred G. Schmidt, p.164 相似文献
19.
After surgical treatment of an inguinal hernia, a 26-year-old male was discharged from hospital with a well healing surgical wound. Four weeks later he was admitted again with a major localized painful swelling of the soft tissues, whereas the clinical examination revealed no further local or systemic signs of inflammation. The immediate operation disclosed no abscess formation, but a large colliquation necrosis of the subcutaneous tissue with an outstanding petroleum-like odour. On toxicological examination of the necrotic tissue, a respective petroleum distillate was found. The patient was confronted with the suspicion of having injected the petroleum preparation himself to prolong the wound healing and finally admitted the self-mutilating behaviour. The pathophysiology, clinical history and morphological findings are discussed in comparison with case reports of chemically induced self-mutilation. 相似文献
20.
Our laboratory was asked to help with the rehydration of mummified human fingertips that had been removed from a recently deceased, unidentified female. Using a solution that was found in the archeological literature, we were able to successfully rehydrate dermal tissues to the extent that fingerprints could be taken. We believe that this solution, which until now has not been described in the forensic literature, is effective, affordable, and relatively easy to produce and use. 相似文献