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71.
Abstract: Ehlers–Danlos syndrome (EDS) type IV is a connective tissue disorder characterized by the inability to produce sufficient amounts of collagen or a defect in the structure of collagen. The most serious complications include a rupture of a viscus or vascular rupture with or without mural dissection. Death may result from internal hemorrhage. This report describes three cases of sudden and unexpected death caused by EDS type IV. Two cases involved hemothorax as a result of dissection of the subclavian artery and aorta, respectively. The third case represented spontaneous pulmonary rupture and hemorrhage. A detailed family history should be sought, and additional specimens collected to confirm the diagnosis, including skin fibroblasts for collagen testing and blood for DNA testing. The forensic pathologist should consider the possibility of EDS type IV upon discovery of spontaneous visceral or arterial rupture and should alert the family members of this hereditary and potentially fatal condition.  相似文献   
72.
Abstract: Conducted energy weapons (such as the Advanced TASER X26 model produced by TASER International), incapacitate individuals by causing muscle contractions. To provide information relevant to development of future potential devices, a “Modifiable Electronic Stimulator” was used to evaluate the effects of changing various parameters of the stimulating pulse. Muscle contraction was affected by pulse power, net/gross charge, pulse duration, and pulse repetition frequency. The contraction force increased linearly as each of these factors was increased. Elimination of a precursor pulse from X26‐like pulses did not have a significant effect on the normalized force measured. Muscle‐contraction force increased as the spacing increased from 5 to 20 cm, with no further change in force above 20 cm of spacing. Therefore, it is suggested that any future developments of new conducted energy weapons should include placement of electrodes a minimum of 20 cm apart so that efficiency of the system is not degraded. In the current study, the 50% probability of fibrillation level of X26‐like pulses ranged from 4 to 5 times higher than the X26 itself. Relatively large variations about the X26 operating level were found not to result in fibrillation or asystole. Therefore, it should be possible to design and build an X26‐type device that operates efficiently at levels higher than the X26.  相似文献   
73.
The aim of this five-wave longitudinal study of 923 early to middle adolescents (50.7% boys; 49.3% girls) and 390 middle to late adolescents (43.3% boys and 56.7% girls) is to provide a comprehensive view on change and stability in identity formation from ages 12 to 20. Several types of change and stability (i.e., mean-level change, rank-order stability, and profile similarity) were assessed for three dimensions of identity formation (i.e., commitment, in-depth exploration, and reconsideration), using adolescent self-report questionnaires. Results revealed changes in identity dimensions towards maturity, indicated by a decreasing tendency for reconsideration, increasingly more in-depth exploration, and increasingly more stable identity dimension profiles. Mean levels of commitment remained stable, and rank-order stability of commitment, in-depth exploration, and reconsideration did not change with age. Overall, girls were more mature with regard to identity formation in early adolescence, but boys had caught up with them by late adolescence. Taken together, our findings indicate that adolescent identity formation is guided by progressive changes in the way adolescents deal with commitments, rather than by changes in the commitments themselves.  相似文献   
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Higher self-concept clarity is related to several adjustment indices and may be promoted by open communication with parents, while problems with self-concept clarity development could enhance internalizing problems (i.e., depressive and anxiety symptoms) in adolescence. This longitudinal study examined linkages between self-concept clarity, adolescents’ open communication with parents, and adolescent depressive and anxiety symptoms. Dutch youths (N = 323; 51.1 % girls; mean age Time 1 = 13.3 years) reported on these constructs over four consecutive annual measurements. Concurrent positive links between open communication and self-concept clarity were found at Time 1. Over time, higher levels of open communication with parents predicted higher self-concept clarity only in middle adolescence (mean age between 14 and 15 years). We also found concurrent associations between self-concept clarity and both depressive and anxiety symptoms. Longitudinally, lower self-concept clarity predicted relatively higher levels of depressive symptoms across all waves, and also higher anxiety levels from Time 1 to Time 2. Conversely, higher levels of anxiety also predicted lower levels of self-concept clarity during the first three waves. Self-concept clarity did not mediate the longitudinal associations between open communication and internalizing symptoms. This study is one of the first to investigate self-concept clarity across adolescence. It highlights the possible importance of both anxiety symptoms and communication with parents in understanding the development of a clear self-concept, and demonstrates an association between lower self-concept clarity and higher levels of later depressive and anxiety symptoms.  相似文献   
76.
Adolescents at-risk for problem behaviors can have more difficulties in developing a firm sense of personal identity. Hence the purpose of this prospective longitudinal study was to scrutinize how externalizing problems in early adolescence impact identity development in middle to late adolescence. Participants were 443 (43.12 % female) Dutch adolescents. Teachers rated their externalizing problem behaviors when participants were 11 or 12 years old and their identity formation was studied during five consecutive years (from 14 to 18 years of age). The sample was divided into four groups: boys and girls with a high versus a low-risk for externalizing problem behaviors. Participants completed a self-report measure of identity commitment, in-depth exploration, and reconsideration of commitment. Multi-group Latent Growth Curve and profile stability analyses were used to evaluate identity development across adolescence. Findings indicated that high-risk boys and girls reported a less structured identity, with lower levels of commitment and higher levels of reconsideration of commitment. Since externalizing problems behaviors and lack of a coherent sense of identity might reinforce each other, early intervention for high-risk adolescents might foster positive youth development.  相似文献   
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As the number and putative importance of political action committees have grown, so too has scholarly attention to this new breed of political organization. Yet this attention has been uneven. Although much is now known about the aggregate spending patterns of PACs, much less is known about their internal lives. The present study attempts to open the PAC black box to empirical inquiry. Drawing on interviews with the managers of 70 Washington-based political action committees, we suggest how theoretical perspectives about formal voluntary associations may be usefully applied in explaining the behavior of PACs. After examining the relationships among several variables — organizational goals, constituency relations and decision making, strategy, and interorganizational relations — we show how these forces affect the behavior of corporate, trade/membership, labor, and nonconnected PACS.  相似文献   
80.
Young, low-income, African American fathers have been at the center of research, practice, and policy on families over the past decade. This article uses a "voicing" analytic technique to examine identities among young, low-income, African American fathers living in an urban setting; the intersections of these identities; and the fathers' perceptions of the influences of familial, peer, and legal systems as barriers and resources in their development as fathers and the sustainability of their fathering roles. The primary questions addressed urban fathers' representations of their transition to fatherhood, intergenerational relationships, transformative events, and visions of a possible self. Results from a survey, focus groups, and interviews suggest that the fathers seek to reinvent themselves and reconstruct their identities by separating from street life, redefine home as a place of stability, and challenge the practices of social and legal systems that appear to work against their responsible fathering.  相似文献   
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