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131.
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   
132.
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   
133.
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:
  相似文献   
134.
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   
135.
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   
136.
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   
137.
In recent years, Congress has recurrently failed to meet its minimum responsibilities in federal budgeting. This article analyzes whether it is possible to repair this problem, using concepts popularized by Allen Schick in his influential article “The Road to PPB.” His article compared the PPB reform effort to the history of budget process reforms that started with the design of the executive budget. It publicized a logical sequence of budget process improvements that started with control and then advanced through management and planning. The article did not substantially address the role of Congress, but eight years after it was published, Congress reasserted its constitutional role in the budget process. Its record of performance since then has ranged from mixed to dysfunctional. The Congress has been criticized for budgetary delays, micromanagement, myopia, procrastination, indiscipline, and an inability to prioritize intelligently. If these faults are set in stone, then an integrated system of budgeting, as described in “The Road to PPB” and related work, is unattainable. On the other hand, if reform of Congressional budgeting is politically feasible, improvements to that system can utilize the unique contributions that a legislature can make to a good system of budgeting.  相似文献   
138.
In this theoretical intervention, I argue that Karl Marx’s theory of value remains a powerful way to understand nature–society relations under capitalism. I suggest environmentalist critiques often misunderstand Marx’s value theory as a theory that “values” workers over nature. His critical theory is better understood as an explanation of how capitalist value exploits both workers and the environment. My defense of Marxian value theory is articulated through five “theses.” I provide empirical illustration based on recent research into the nitrogen fertilizer industry. (1) Value theory does not refer to all values. (2) Marx’s contention that nature does not contribute to value helps us explain its degradation under capitalism. (3) Marx’s value theory rooted in production allows for a critique of environmental economic valuation schemes (e.g. payments for ecosystem services) which are based on neoclassical value theories rooted in consumption/exchange. (4) Value is abstract social labor, but that means it also abstracts from nature. (5) Capital does value certain parts of nature and that matters. I conclude by advocating a “value theory of nature” in the spirit of Diane Elson’s powerful articulation of Marx’s “value theory of labor.”  相似文献   
139.
Punctuated equilibrium theory (PET) suggests that the policy process is characterized by long periods of incremental change and short periods of punctuated change. The impetus for the latter is usually a focusing event that breaks open policy monopolies, allowing for major changes in legislative decision making. While a burgeoning body of literature, a shortcoming in the PET literature is that it has yet to explain why focusing events and subsequent breakdowns in policy monopolies sometimes fail to result in punctuated policy. We integrate theories on cultural change with punctuated equilibrium to explain why focusing events do not always result in the dramatic policy changes that we might expect. Specifically, we use the context of national energy policy and the lexical database, Google Ngram Viewer, to trace punctuating energy‐related events and the occurrence or lack thereof subsequent policy change from 1952 to 2000.  相似文献   
140.
About half of the nations that experience civil war eventually relapse into renewed conflict within a few years after the original war ends. This observation has motivated a stream of research into the factors that affect the risk of peace failure in the aftermath of civil war. While the outcome of the previous civil war—for example, military victory versus peace agreement—structures the post-war environment in ways that affect the risk of peace failure, the capacity of the post-war state to enact and implement policies that affect the incentives for and capacity of groups to undertake armed violence as a means of advancing their interests should also affect the risks of peace failure. Using Geddes’ categories of nondemocratic regime types, we will present a theory of how different regime types have varying capacities to repress and/or implement accommodative policies that affect the risk of peace failure. We test propositions derived from this theory with a series of event history models. Our findings suggest that while peace agreements significantly increase the duration of post-civil war peace, peace agreements involving some types of nondemocratic regimes actually increase the risk of post-civil war peace failure.  相似文献   
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