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231.
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   
232.
Hacking trauma is prevalent in forensic cases involving genocide and dismemberment, but research into the identification of this type of trauma is lacking. The present study examines characteristics of hacking and blunt force skeletal trauma in order to determine if there is a point at which blunt force trauma becomes distinguishable from hacking trauma. Ten implements with a range of blade angles (i.e., the striking surface of the implement) were used in conjunction with a controlled-force hacking device to impact 100 limb bones of white-tailed deer (Odocoileus virginianus). Observations of the trauma included the occurrence and degree of fragmentation, the entrance widths of the impacts, and composite scores of six hacking characteristics, especially the distinctive V-shaped kerf. ANOVA tests and regression analyses were used to assess the relationships between these characteristics and the blade angles. A significant relationship (p-value = 0.011) was found between the composite hacking scores and the blade angles, indicating that blunt force and hacking trauma can be distinguished. The entrance widths of the impacts exhibited a significant relationship with the blade angles (p-value = 0.037). There was also a significant relationship between the visibility of a V-shaped kerf in the bones (p-value = 0.003), with visibility decreasing around the 60° blade angle. These data should assist in establishing guidelines to differentiate hacking and blunt force skeletal trauma in cases where the implement is on a spectrum between sharp and blunt.  相似文献   
233.
Focusing on identity development explorations enables a greater understanding of contexts that affect immigrant adolescents. Utilizing thematic and grounded narrative analysis of 46 journal writings, during a one-month period, from first and second generation Vietnamese adolescents ranging in age from 15 to 18 (26 residents of a culturally and politically active ethnic enclave in Southern California; 20 adolescents living outside the enclave), this study establishes ways in which a focus on social context and exploration processes illuminates the complexity of immigrant adolescents’ identity formation. The two groups shared many similarities, including precipitants to exploration and steps undertaken to explore identity. However, two factors—social and cultural influences and emotional reactions—revealed interesting contrasts distinguishing enclave from non-enclave dwelling Vietnamese adolescents. Data also suggested that immigrant adolescents strive to integrate different domains of identity (ethnicity, gender, career) both with one another and with the historical, social, and cultural contexts they occupy.
Jaan ValsinerEmail:
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234.
The current cross-sectional study investigated the links between various dimensions of organized activity involvement and depressive symptoms, loneliness, and peer victimization in an ethnically and economically diverse sample of adolescents (N = 152; 58% female). Results indicate that adolescents who were involved in organized activities for more years also reported lower levels of loneliness. There was evidence of diminishing returns when adolescents were very highly involved in organized activities; those who were either under- or over-involved reported the highest levels of depressive symptoms. Conversely, findings indicate that adolescents who participated in a narrow or wide range of activity contexts reported the lowest levels of depressive symptoms. In addition, results suggested that the relation between organized activity involvement and adjustment differs among adolescents from diverse ethnic and socioeconomic backgrounds. Findings from the current study also underscore the importance of considering multiple indices of activity involvement when assessing its association with adjustment.
Edin T. RandallEmail:
  相似文献   
235.
What motivates citizens to run for office? Recent work has shown that early life parental socialization is strongly associated with a desire to run for office. However, parents not only shape their children’s political environment, they also pass along their genes to those same children. A growing area of research has shown that individual differences in a wide range of political behaviors and attitudes are linked to genetic differences. As a result, genetic factors may confound the observed political similarities among parents and their children. This study analyzes Swedish register data containing information on all nominated and elected candidates in the ten parliamentary, county council, and municipal elections from 1982 to 2014 for a large sample of adoptees and their adoptive and biological parents. By studying the similarity in political ambition within both adoptive and biological families, our research design allows us to disentangle so-called “pre-birth” factors, such as genes and pre-natal environment, and “post-birth” factors like parental socialization. We find that the likelihood of standing as a political candidate is twice as high if one’s parent has been a candidate. We also find that the effects of pre-birth and post-birth factors are approximately equal in size. In addition, we test a number of potential pre- and post-birth transmission mechanisms. First, disconfirming our expectations, the pre-birth effects do not seem to be mediated by cognitive ability or leadership skills. Second, consistent with a role modeling mechanism, we find evidence of a strong transmission in candidacy status between rearing mothers and their daughters.  相似文献   
236.
Abstract

Scalability can be understood as the ability to expand without changing. Yet, expanding an intervention to a global scale, we suggest, is a significant and difficult accomplishment. In this paper we propose to explore the kind of evidential exigencies that this accomplishment involves. To do so, we focus on the field of global health and examine how child immunization against the pneumococcus bacterium has been scaled up in low-income countries. The paper first attends to initial epidemiological scrutiny that revealed the existence of a large-scale public health problem and the possibility of an expandable solution (vaccination). It then describes the set-up of a funding arrangement using overseas aid to purchase vaccine doses manufactured by pharmaceutical companies, before paying attention to various frictions that affect the widespread use of pneumococcal vaccines. In these different moments through which scalability is accomplished, always partially and temporarily, we show that a dual activity can be witnessed, a pivoting between referential work and forward projection. To conclude, we suggest that scalability is more usefully approached as a form of expansion that is always attentive to the possibilities of change.  相似文献   
237.
Abstract

This paper explores an example of global politics in action by attending to the modalities and outcomes of United Nations negotiations on global warming. More precisely, the paper ethnographically traces how the capacity of tropical forests to act as carbon sinks is turned into a matter of global concern. The focus is on a negotiated policy called Reducing Emissions from Deforestation and forest Degradation (REDD+) and its anchoring in the Democratic Republic of the Congo, whose territory contains the second largest area of rainforest after Brazil. The paper discusses the importance of the promissory in climate actions, the multivalence of what is at stake and the porosity and resilience of national demarcation. To do so, it identifies three moments and sites of geopolitical re-composition: the formulation of international consensus, the work of preparatory agents and the quest for metrological inclusiveness. These moments and sites point to the theatricality and semi-secrecy of United Nations negotiations, the mobilizing activities of expatriate consultants hired with overseas aid funding and the unstable evidential grounds on which emission reduction efforts are based. The paper suggests that, through this series of processes, the carbon stored by tropical forests becomes a matter of global exigency.  相似文献   
238.
Pay for performance (PFP) remains one of the most controversial policy debates in the New Public Management reform era. Skepticism about PFP in the public sector is often grounded in theories of public service motivation that suggest a misalignment between PFP's focus on extrinsic market‐based pay incentives and intrinsically motivated government workers. Frequently missing from this analysis, however, is any consideration for whether PFP leads to positive “sorting” effects on the composition of a government agency's workforce through attraction, selection, and attrition processes. Using data from two waves of the Schools and Staffing Survey, the authors examine whether PFP influences the sorting patterns of K–12 public schoolteachers across U.S. school districts. Findings show that, on average, school districts that adopted PFP secured new teacher hires who had graduated from colleges and universities with average SAT scores that were about 30 points higher than the new teacher cohorts hired by districts that did not adopt PFP.  相似文献   
239.
240.
Affluent Americans support more conservative economic policies than the nonaffluent, and government responds disproportionately to these views. Yet little is known about the emergence of these consequential views. We develop, test, and find support for a theory of class cultural norms: These preferences are partly traceable to socialization that occurs on predominantly affluent college campuses, especially those with norms of financial gain, and especially among socially embedded students. The economic views of the student's cohort also matter, in part independently of affluence. We use a large panel data set with a high response rate and more rigorous causal inference strategies than previous socialization studies. The affluent campus effect holds with matching, among students with limited school choice, and in a natural experiment; and it passes placebo tests. College socialization partly explains why affluent Americans support economically conservative policies.  相似文献   
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