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171.
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   
172.
The media allow crime to infiltrate the public’s consciousness in every conceivable way, thereby playing a major role in shaping the public’s opinion and attitude toward crime and crime issues (Barak, 1995; Fields & Jerin, 1996; Kappeler & Potter, 2005). Reporters constantly talk about crime, and crime related stories dominate the headlines of local and national newspaper outlets (Dowler, 2003; Pizarro et al, 2007). Some of the most highly rated television programs are based on crime plots and people across social, political, and racial demographics are constantly engaged in crime dialogue generated from local or national news stories. When the focus of these mediums is on youth they become even more profound and contentious. The images portrayed conjure up stereotypes that lead to fear and inflammatory remarks that become entrenched into the national lexicon. The current study uses data from the National Opinion Survey of Crime and Justice to test the relationship between crime-related media viewership and fear of victimization within a nationally representative adult sample. Approximately 42.67% of respondents reported regularly watching crime shows and about the same proportion (42.83%) believed their local media paid too much attention to violent crime. In addition to regular crime-show viewership, confidence in the police, gender, and recent contact with the police were associated with fear of victimization. This article adds to an existing body of research through a largely unexplored area in the administration of justice. It does so within the context of the U.S. juvenile justice system.  相似文献   
173.
Research indicates that voters are not particularly effective at removing corrupt politicians from office, in part because voters make decisions on the basis of many competing factors. Party leaders are much more single-minded than voters and will choose to deselect implicated legislators if it means maintaining a positive party reputation and improving the odds of winning a legislative majority. We examine renominations to Italy’s legislature in two periods marked by corruption. We compare these renomination patterns with those from the prior legislature, when corruption lacked political salience. Our analysis shows that incumbent renominations are negatively associated with the number of press mentions that link the incumbent to corruption—but only when corruption is salient to the public. Our study highlights the importance of party leaders in forcing malfeasant legislators out of office—and reducing corruption—and redirects attention from voters to political elites as a critical channel in enforcing democratic accountability.  相似文献   
174.
Getting along with peers becomes increasingly important to health and well-being during early adolescence (10–14 years). Young adolescents may succeed with peers when they are well-liked by and popular among the larger peer group (or at the group-level of social complexity). They might also fare well with peers when they are able to form numerous mutual and high quality friendships (at the dyadic-level of social complexity). Theory emphasizes the interrelatedness of different types of peer experiences, but few longitudinal studies have examined the interplay among and between group- and dyadic-level peer experiences in the same study. As a result, it is not known whether group-level peer experiences are predictors of dyadic-level peer experiences, and/or vice versa. To address this limitation, this study examined the prospective and reciprocal relations between four indices of peer experiences, preference (or being highly liked and not disliked by peers), popularity (or having a reputation as popular), friendship quantity (or having many mutual friends), and friendship or relationship quality, during early adolescence. Participants were 271 adolescents (49% girls; Mage?=?11.52 years) who completed peer nominations of preference and popularity, a self-report measure of friendship quality, and nominated friends at two waves (Wave 1: November, Grade 6; Wave 2: October, Grade 7). Structural equation modeling indicated that friendship quantity predicted increases in preference and popularity and that friendship quality predicted increases in friendship quantity. Initial popularity was associated with decreases in preference. The importance of these findings for future research is discussed along with study limitations.  相似文献   
175.
Adverse childhood experiences (ACEs) have been identified as a key risk factor associated with a wide range of negative life outcomes, including juvenile delinquency. Much less work has explored whether certain combinations of ACEs, or typologies of trauma, exist, and whether or not these subgroups are differentially associated with certain youth-level and/or community-level characteristics. The current study uses latent class analysis to examine ACE typologies among a sample of over 92,000 juvenile offenders between the ages of 10 and 18 in the state of Florida (52% male, 37.3% White, 46.8% Black, 15.9% Hispanic). Multilevel multinomial logistic regression is used to assess the relationship between both individual- and community-level factors and class membership. The findings suggest that a total of five distinct ACE typologies exist among the sample of juvenile offenders, and age, race, and sex were significantly associated with class membership. Additionally, controlling for individual-level characteristics, community-level measures of immigrant concentration, residential instability, and two separate measures of concentrated disadvantage and affluence were significantly related to class membership. This study contributes to the understanding of adverse childhood experiences, and adds to existing knowledge regarding the relationship between contextual factors and childhood abuse, maltreatment, and trauma. The identification of ACE subgroups with distinct characteristics may help guide prevention strategies and tailor treatment provided by the juvenile justice system.  相似文献   
176.
Psychological empowerment encompasses several key aspects of youth civic and sociopolitical development. Most research has focused on psychological empowerment’s emotional component, which entails learned hopefulness about one’s own ability to participate in and lead community change efforts. Fewer studies have assessed critical awareness of how social power operates—psychological empowerment’s cognitive component. The confluence of these two components has been termed critical hopefulness. A complex relationship exists between these two components, and previous research has found relatively small proportions of participants reporting both high levels of critical awareness and simultaneously high levels of hopefulness about their ability to exert influence in the sociopolitical domain. The current study of urban high school students in the Northeastern U.S. (n?=?389; 53.5% female) investigates heterogeneity according to these two components of psychological empowerment. Latent class cluster analyses were conducted and seven distinct groups of participants emerged. Students identifying as Hispanic/Latinx were more likely to be classified into a profile group exhibiting critical hopefulness. Differences were observed between psychological empowerment profile groups on self-reported levels of psychological sense of community, civic engagement, and social justice orientation. Furthermore, a larger proportion of this overall sample was classified into groups that exhibited critical hopefulness than in a previous study of adults. These findings provide useful insights for efforts to engage young people in civic life and to promote sociopolitical development.  相似文献   
177.
Document examiners sometimes eliminate writers on the basis of differences which are given too much weight. This article is an attempt to explain some conditions whereby differences in the writing of one individual are misinterpreted as significant differences, when they are actually caused by conditions which are unknown to the examiner.  相似文献   
178.
The activity of calcium pumping adenosine triphosphatase (Ca2+-ATPase) in cardiac sarcoplasmic reticulum plays a pivotal role in myocardiac contraction-relaxation. The Ca2+-ATPase activity is controlled by phosphorylation and dephosphorylation of a sarcoplasmic reticulum protein "phospholamban" in response to neurotransmitters and drugs. To clarify the role of Ca2+-ATPase in the development of cardiac rigor mortis, we examined the changes of cardiac rigidity and cardiac sarcoplasmic reticulum Ca2+-ATPase activity up to 5 h after the decapitation of rats. Fifteen minutes after decapitation, the rats showed a cardiac rigidity on left ventricles. After 30 min, rigidity was obvious over the whole heart. After 1 h, the rigidity reached a high degree which was maintained for the rest of the observation period. On the other hand, the Ca2+-ATPase activity controlled by phosphorylation and dephosphorylation of phospholamban did not change for the whole observation period (5 h). Another Ca2+-ATPase activity representing the total amount of Ca2+-ATPase in sarcoplasmic reticulum gradually decreased. The data suggest that no significant phosphorylation or dephosphorylation of phospholamban occurs for a short time, at least for 5 h, after death and that the Ca2+-ATPase tends to relax the myocardium against the development of cardiac rigor mortis.  相似文献   
179.
In order to establish pathological evidence in dermis for distinguishing between sequelae of electrical torture and those of other superficial injuries, the skin of eleven fully anaesthetized Danish Landrace pigs have been exposed to heat and electrical energy from either 50 Hz alternating current (a.c.) or direct current (d.c.) via 12 mm large contact knobs or via a pointed 0.5 mm large electrode (only 50 Hz a.c.). The lesions have been examined from 1 to 126 days after the injury. While heat lesions exposed to energy lower than 60 joule only gave minor changes, heat lesions exposed to more than 60 joule showed changes in both collagen fibres (basophilic or eosinophilic fibres without any birefringence or coarse cross-striation in polarized light, respectively) and dermal cells (granular cytoplasm). Areas exposed to 50 Hz a.c. via 0.5 mm. electrode showed basophilic collagen fibres and in a few biopsies on day 7 calcium salts on collagen fibres. Using 12 mm large electrodes the changes were minor, but basophilic and eosinophilic collagen fibres with no birefringence or with fine/coarse cross-striation respectively were seen. Even cells with 'vesicular nuclei' were seen on day 1 and 2 after the injury. The changes in the anode area showed resemblance to that of heat lesions (basophilic collagen fibres). Eosinophilic collagen fibres with fine densely spaced cross-striation in polarized light and 'vesicular nuclei' as well as collagen fibres with calcium salts were seen in the cathode lesions. It is concluded that the dermal changes in the cathode area are specific for electrical injury from day 1 to 14. However, earlier studies have demonstrated dermal changes specific for electrical injury at day 0 and the presence of calcified collagen fibres up to 2 months after injury. The dermal changes in anode lesions were non specific and could not be differentiated from those found in heat lesions. Alternating current lesions (50 Hz) were specific from day 1 to day 7, when the pointed electrode was used, but only in a few days when the energy was transferred via the 12-mm electrodes.  相似文献   
180.
Malaysians firms have made inroads into the non-traditional export markets. Such ventures are expected to result in increased knowledge about the marketing systems that are posited to be different from the traditional export markets. This paper reports on the perceived improvement in marketing competencies of Malaysian exporters. The results of data analysis show that there are five dimensions of marketing competency. In ranking order, segmenting and targeting competency is ranked highest followed by product management, export management, product differentiation and promotion. Multiple regression analysis was performed to test the explanatory power of each marketing competency on export performance of firms exporting to China and ASEAN countries. The result revealed that none of the marketing competency explained the variation in export performance for the China market. However, among exporters in ASEAN countries, it was noted that promotion competency resulted in a negative impact on both measures of export performance. Product competency is positively associated with financial measure of export performance. Competencies in segmenting and targeting, and export management are positively associated with non-financial performance.  相似文献   
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