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Postmortem computed tomography (PMCT) is integrated into the evaluation of decedents in several American medical examiner offices and medicolegal death investigative centers in many other countries. We retrospectively investigated the value of PMCT in a series of firearm homicide cases from a statewide centralized medical examiner’s office that occurred during 2016. Autopsies were performed or supervised by board-certified forensic pathologists who reviewed the PMCT scans prior to autopsy. PMCT scans were re-evaluated by a forensic radiologist blinded to the autopsy findings and scored by body region (head–neck, thoracoabdominal, and extremities). Injury discrepancies were scored using a modified Goldman classification and analyzed with McNemar’s test. We included 60 males and 20 females (median age 31 years, range 3–73). Based on PMCT, 56 (79.1%) cases had injuries relevant to the cause of death in a single body region (24 head–neck region, 32 thoracoabdominal region). Out of these 56 cases, 9 had a missed major diagnosis by PMCT outside that region, including 6 extremity injuries visible during standard external examination. Yet all had evident lethal firearm injury. We showed that PMCT identifies major firearm injuries in homicide victims and excludes injuries related to the cause of death in other regions when a single body region is injured. Although PMCT has a known limited sensitivity for soft tissue and vascular pathology, it can be combined with external examination to potentially reduce or focus dissections in some of these cases depending on the circumstances and medicolegal needs.  相似文献   
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This paper examines the reliability of Structure from Motion (SfM) photogrammetry as a tool in the capture of forensic footwear marks. This is applicable to photogrammetry freeware DigTrace but is equally relevant to other SfM solutions. SfM simply requires a digital camera, a scale bar, and a selection of oblique photographs of the trace in question taken at the scene. The output is a digital three-dimensional point cloud of the surface and any plastic trace thereon. The first section of this paper examines the reliability of photogrammetry to capture the same data when repeatedly used on one impression, while the second part assesses the impact of varying cameras. Using cloud to cloud comparisons that measure the distance between two-point clouds, we assess the variability between models. The results highlight how little variability is evident and therefore speak to the accuracy and consistency of such techniques in the capture of three-dimensional traces. Using this method, 3D footwear impressions can, in many substrates, be collected with a repeatability of 97% with any variation between models less than ~0.5 mm.  相似文献   
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Postmortem magnetic resonance imaging (MRI) is rarely used for the radiologic assessment of gunshot injuries, although it has clear advantages over postmortem computed tomography (CT) with regard to the imaging of soft tissue injuries. Another benefit in using MRI is that lodged projectiles composed of nonferromagnetic material such as lead present only marginal metal artifacts compared with severe artifacts on CT. This case report presents CT and MRI findings in a case with two gunshot wounds to the neck: a perforating wound and a nonperforating wound with a lead bullet lodged in the cervical spine. The decedent underwent CT and MRI before the scheduled autopsy. A ring of radiopaque material under the dermis in the fatty tissue was identified at both entrance wounds on CT, which was indicative of contact shots. The perforating gunshot was clearly indicated on CT by bullet fragments along the wound channel through the perforated 6th cervical vertebra and the fractured cricoid cartilage at the exit wound. The second trajectory, however, was only assumed based on the presence of gunshot residues at the entrance wound and the position of the lodged bullet. The radiologic assessment was severely impeded by the metal artifacts on CT. Barely noticeable metal artifacts on MRI allowed for clear visualization of the soft tissue injuries and the ruptured medulla oblongata. Only MRI clarified the soft tissue injuries of the brainstem noninvasively, which could provide specific and graphic information on the rapidity of death and the incapacitation of the victim.  相似文献   
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Sociometric nominations, social cognitive maps, and self-report questionnaires were completed in consecutive years by 327 students (56% girls) followed longitudinally from grade 7 to grade 8 to examine the stability of social standing in peer groups and correlates of changes in social standing. Social preference, perceived popularity, network centrality, and leadership were moderately stable from grade 7 to grade 8. Alcohol use and relational aggression in grade 7 predicted changes in social preference and centrality, respectively, between grade 7 and grade 8, but these effects were moderated by gender and ethnicity. Changes in social standing from grade 7 to grade 8 were unrelated to grade 8 physical aggression, relational aggression, and alcohol use after controlling for the grade 7 corollaries of these behaviors. Results are discussed in terms of their implications for understanding links between social standing and problem behaviors during adolescence.
Jennifer E. LansfordEmail:
  相似文献   
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Structured analytic techniques (SATs) are intended to improve intelligence analysis by checking the two canonical sources of error: systematic biases and random noise. Although both goals are achievable, no one knows how close the current generation of SATs comes to achieving either of them. We identify two root problems: (1) SATs treat bipolar biases as unipolar. As a result, we lack metrics for gauging possible over-shooting—and have no way of knowing when SATs that focus on suppressing one bias (e.g., over-confidence) are triggering the opposing bias (e.g., under-confidence); (2) SATs tacitly assume that problem decomposition (e.g., breaking reasoning into rows and columns of matrices corresponding to hypotheses and evidence) is a sound means of reducing noise in assessments. But no one has ever actually tested whether decomposition is adding or subtracting noise from the analytic process—and there are good reasons for suspecting that decomposition will, on balance, degrade the reliability of analytic judgment. The central shortcoming is that SATs have not been subject to sustained scientific of the sort that could reveal when they are helping or harming the cause of delivering accurate assessments of the world to the policy community.  相似文献   
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Research on negative campaigning has largely overlooked the role of stereotypes. In this study, we argue that the gender and partisan stereotypes associated with traits and policy issues interact with a candidate’s gender and partisanship to shape the effectiveness of campaign attacks. We draw on expectancy-violation theory to argue that candidates may be evaluated more harshly when attacks suggest the candidate has violated stereotypic assumptions about their group. Thus, attacks on a candidate’s “home turf,” or those traits or issues traditionally associated with their party or gender, may be more effective in reducing support for the attacked candidate. We use two survey experiments to examine the effects of stereotype-based attacks—a Trait Attack Study and an Issue Attack Study. The results suggest that female candidates are particularly vulnerable to trait based attacks that challenge stereotypically feminine strengths. Both male and female candidates proved vulnerable to attacks on policy issues stereotypically associated with their party and gender, but the negative effects of all forms of stereotype-based attacks were especially large for democratic women. Our results offer new insights into the use of stereotypes in negative campaigning and their consequences for the electoral fortunes of political candidates.  相似文献   
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