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91.
Ethanol formation in unadulterated postmortem tissues 总被引:2,自引:0,他引:2
During the investigation of aviation accidents, postmortem samples obtained from fatal accident victims are submitted to the FAA's Civil Aerospace Medical Institute (CAMI) for toxicological analysis. During toxicological evaluations, ethanol analysis is performed on all cases. Many species of bacteria, yeast, and fungi have the ability to produce ethanol and other volatile organic compounds in postmortem specimens. The potential for postmortem ethanol formation complicates the interpretation of ethanol-positive results from accident victims. Therefore, the prevention of ethanol formation at all steps following specimen collection is a priority. Sodium fluoride is the most commonly used preservative for postmortem specimens. Several studies have been published detailing the effectiveness of sodium fluoride for the prevention of ethanol formation in blood and urine specimens; however, our laboratory receives blood or urine in approximately 70% of cases. Thus, we frequently rely on tissue specimens for ethanol analysis. The postmortem tissue specimens received by our laboratory have generally been subjected to severe trauma and may have been exposed to numerous microbial species capable of ethanol production. With this in mind, we designed an experiment utilizing unadulterated tissue specimens obtained from aviation accident victims to determine the effectiveness of sodium fluoride at various storage temperatures for the prevention of microbial ethanol formation. We found that without preservative, specimens stored at 4 degrees C for 96 h showed an increase in ethanol concentration ranging from 22 to 75 mg/hg (average 42 +/- 15 mg/hg). At 25 degrees C, these same specimens showed an increase ranging from 19 to 84 mg/hg (average 45 +/- 22 mg/hg). With the addition of 1.00% sodium fluoride, there was no significant increase in ethanol concentration at either temperature. 相似文献
92.
Voluntary environmental programs (VEPs) have become a popular alternative to traditional regulation. However, little is known about whether these programs are sending accurate signals about the environmental practices of their participants. As a means for understanding signaling accuracy, this research investigates VEP design characteristics. The findings suggest that there are four distinct types of programs with varying degrees of rigor. Because information for differentiating among program types is limited, less rigorous VEPs can signal that their administrative, environmental performance and conformance requirements are comparable to programs with more robust designs. Further, the lack of monitoring and sanctions in less rigorous programs create opportunities for participants to free-ride and receive benefits without satisfying VEP requirements. Unless some means of distinguishing among program types is implemented, these issues can threaten the long term viability of VEPs as a tool for environmental protection, and the credibility of market mechanisms more broadly. 相似文献
93.
Trutz Von Trotha 《Crime, Law and Social Change》1995,24(1):37-47
Recently an increasing amount of violent racism has been directed at foreigners in Germany. Current theoretical explanations are deficient because they fail to recognize the historical role of the political culture. This paper argues that political elites are responsible for initiating rhetoric and policy that has created an environment where xenophobic and racist violence can flourish. Positive normalization is defined as a process for the neutralization of the violent Nazi past and the reconstruction of a German nationalist identity. Negative normalization is described as responsible for the decriminalization and trivialization of xenophobic and racist violence. It is argued that unless changes within the German political culture are taken into account, criminological perspectives on the current situation will inevitably be limited. 相似文献
94.
95.
Our article explores the contribution of local initiatives to the creation of path dependencies for energy transition in Germany and Japan in the face of resistance from entrenched incumbents at the national level. We use a process‐tracing methodology based partly on interviews with local participants. In particular, we explore the role of local initiatives in securing “socio‐political space” for the expansion of renewable energy (RE) and in embedding themselves in “ecosystems” of public and private institutions. German energy activists were more successful than their Japanese counterparts in expanding this space and creating positive feedback in part because they were able to build horizontal networks that anchored the energy transition firmly in local communities. Although problems with grid technology have led to retrenchment in both cases, Japanese activists' reliance on vertical networks has limited their ability to weather a backlash from national government and utility actors. Our study demonstrates the interaction of political, economic/technological, and legitimation paths to energy transition and highlights the importance of the latter two. 相似文献
96.
AbstractA discrete choice experiment was conducted to discover the relative importance of five characteristics of developing countries considered by people when choosing countries to donate money to. The experiment was administered via an online survey involving almost 700 university student participants (potential donors). The most important recipient country characteristic for participants on average is hunger and malnutrition, followed by child mortality, quality of infrastructure, income per capita, and, least importantly, ties to the donor’s home country. A cluster analysis of participants’ individual ‘part worth utilities’ representing the relative importance of the country characteristics reveals they are not strongly correlated with participants’ demographic characteristics. 相似文献
97.
Kaylin M. Greene Bora Lee Nicole Constance Kathryn Hynes 《Journal of youth and adolescence》2013,42(10):1557-1572
Prior research suggests that youths’ engagement in out-of-school time programs may be a crucial factor linking program participation to positive outcomes during adolescence. Guided by the theoretical concept of flow and by stage-environment fit theory, the present study explored correlates of engagement in youth programs. Engagement was conceptualized as the extent to which youth found the program activities enjoyable, interesting, and challenging. The current study examined how program content, monetary incentives, and youth demographic characteristics were linked to youth engagement among a sample of primarily low-income middle and high school youth attending 30 out-of-school programs (n = 435, 51 % female). Results from multilevel models suggested that program content and staff quality were strongly associated with youth engagement. Youth who reported learning new skills, learning about college, and learning about jobs through activities in the program were more engaged, as were youth who found the staff caring and competent. Results demonstrated that the link between learning content for the future and engagement was stronger for older youth than younger youth. In addition, there was a trend suggesting that providing a monetary incentive was associated negatively with youth engagement. Taken as a whole, these findings have important implications for researchers, practitioners, and policymakers interested in understanding the characteristics of out-of-school time programs that engage older youth. 相似文献
98.
Alex R. Piquero Nadine M. Connell Nicole Leeper Piquero David P. Farrington Wesley G. Jennings 《Journal of youth and adolescence》2013,42(3):444-453
The perpetration of bullying is a significant issue among researchers, policymakers, and the general public. Although researchers have examined the link between bullying and subsequent antisocial behavior, data and methodological limitations have hampered firm conclusions. This study uses longitudinal data from 411 males in the Cambridge Study in Delinquent Development from ages 8 to 56 in order to examine the relationship between adolescent bullying and distinct late middle adulthood trajectories of offending, in which different groups of males follow different offending pathways. Results show that self-reported bullying predicts only certain adult offending trajectories but that the effect becomes insignificant once controls are introduced for childhood risk factors, although this may be due to the small number of the most chronic offenders. Study implications and directions for future research are noted. 相似文献
99.
Nicole Lafko Breslend Erin K. Shoulberg Julia D. McQuade Dianna Murray-Close 《Journal of youth and adolescence》2018,47(9):1894-1906
Youth in early adolescence are highly concerned with being popular in the peer group, but the desire to be popular can have maladaptive consequences for individuals. In fact, qualitative work suggests that youth with high popularity goals who are nonetheless unpopular have negative experiences with their peers. However, little quantitative work has examined this possibility. The purpose of the current study was to examine if popularity goals were linked with physical (e.g., being hit) and relational (e.g., being excluded) victimization and peer rejection, particularly for individuals who strived for popularity but were viewed by their peers as unpopular. Late elementary and early middle school participants (N?=?205; 54% female) completed self-reports of popularity goals and peer nominations of popularity and peer rejection. Teachers reported on students’ experiences of relational and physical victimization. Peer nominated popularity and gender were moderators of the association between popularity goals and negative peer experiences. Consistent with hypotheses, girls who were unpopular but wanted to be popular were more likely to experience peer rejection and relational victimization. Unexpectedly, boys who were unpopular but did not desire to be popular were more likely to be rejected and relationally victimized. The findings suggest that intervention and prevention programs may benefit from addressing the social status goals of low status youth in a gender-specific manner. 相似文献
100.
The intersections between homebirth and masculine identities have not been widely explored. In this paper, we focus on the construction/contestation of masculinity in South African men’s narratives of planning and experiencing homebirth. Drawing on 20 interviews conducted with a sample of 5 men and couples in 2013–2014, a narrative analysis found men constructed ideal masculinities and ways of being a man in relation to homebirth. The paper focuses on the multiple representations of masculinity constructed in men’s talk about homebirth and traces their efforts to articulate a masculine perspective of birth. Men grappled with the meanings of ‘being there’ as a man during labour/birth and articulated alternative modes of being a man that valued and accommodated relationality, passivity and containment. Men thus articulated ways of being present and passive during homebirth that challenged normative constructions of masculinity. The notion of selfless masculinity emerged as a key masculine ideal in which giving and service during birth was constructed as integral to being a good father and man. However, competing forms of normative masculinity constructed in men’s narratives meant gender tensions remained in the continued salience of traditional masculine meta-narratives, such as being the ‘breadwinner’. 相似文献