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821.
Developmental imbalance models attribute the rise in risk-taking during adolescence to a universal imbalance between rising reward sensitivity and lagging cognitive control. This study tested predictions of an alternate Lifespan Wisdom Model that distinguishes between exploratory/adaptive (e.g., sensation seeking) and maladaptive (e.g., acting-without-thinking, delay discounting) risk-taking propensities and attributes the latter to a sub-set of youth with weak cognitive control. Latent trajectory modeling of six waves of data from 387 adolescents (52% females; spanning average ages of 11–18 years) revealed distinct sub-groups with heterogeneous trajectory patterns for acting-without-thinking and delay-discounting. Only those trajectory groups with weak cognitive control, characterized as “high-increasing” acting-without thinking and “high-stable” delay discounting were predictive of a maladaptive risk-taking outcome, namely substance use disorder. Sensation seeking demonstrated a universal peak, but high levels of sensation seeking were not associated with weakness in cognitive control and were unrelated to substance use disorder, controlling for impulsivity. The findings suggest that maladaptive risk-taking characterized by weak cognitive control over reward-driven impulses is a phenomenon limited to only a sub-set of youth.  相似文献   
822.
Despite the large contingent of students living in rural areas, existing research on the processes that precede the college enrollment of rural adolescents is limited. With a particular focus on gender, this study investigated rural adolescents’ perceptions of family and place and how these perceptions related to their educational aspirations and subsequent college enrollment using a nationwide sample of rural adolescents (N?=?3456; 52.5% female). Female adolescents reported higher academic achievement, educational aspirations, parental expectations, and family responsibility and enrolled in two-year and four-year institutions at greater rates compared to male adolescents, who reported significantly higher rural identity and perceptions of job opportunities in the rural community. Utilizing a multiple group moderated mediation approach, the results provided evidence that adolescents’ increased perceptions of their parents’ educational expectations were associated with increased educational aspirations and college enrollment and that adolescents’ increased perceptions of job opportunities in their rural community were associated with decreased educational aspirations. In addition, the results showed that gender moderated the relation between perceptions of job opportunities in the rural community and postsecondary enrollment. These findings highlight how the developmental resources of family and place relate to adolescents’ educational aspirations and subsequent postsecondary enrollment.  相似文献   
823.
This paper appraises the role of critical-feminist figurations within the environmental humanities, focusing on the capacity of figures to produce situated environmental knowledges and pose site-specific ethical obligations. We turn to four environments—the home, the skies, the seas and the microscopic—to examine the work that various figures do in these contexts. We elucidate how diverse figures—ranging from companion animals to birds, undersea creatures and bugs—reflect productive traffic between longstanding concerns in feminist theory and the environmental humanities, and generate new insights related to situated knowledges, feminist care-ethics and the politics of everyday sensory encounters. We also argue, however, that certain figures have tested the limits of theoretical approaches which have emerged as the product of dialogue between feminist theory and environmental studies. In particular, we explore how particular figures have complicated ethical questions of how to intervene in broad environmental threats borne of anthropogenic activities, and of who or what to include in relational ethical frameworks.  相似文献   
824.
We set out by noting the preference for circular flows in ecological thought, and the related abhorrence of inefficiency and waste that Western ecology shares with mainstream economic thinking. This has often been manifest in a shared disdain both for uncontained, free-burning fire and for ‘unmanaged’ sexual desire. The paper constructs a ‘pyrosexual’ counter-narrative that explores the mutually constitutive and generative implication of sex and fire. Bringing together the solar ecology of Georges Bataille, feminist and queer thinking about sexuality and reproduction, and a range of ways of theorising biological life and fire, we explore how fire mediates between organismic desire and the energetic dynamics of the earth and solar system. The first section takes a genealogical approach to fire and sex that traces their entanglement from the initial ‘assembling’ of fire through to the emergence of a fire-handling creature. The second section looks at how fire has been contained and intensified by human actors, and the role that heat-driven transformations of inorganic matter have played in the incitement and channeling of desire in urban spaces. The third section addresses the development of industrial ‘heat engines’ and the implications for desire and reproduction of tapping vast reservoirs of subterranean solar energy. We round off by beginning to consider what alternative possibilities might lie in the renegotiation of sex and fire on a planet undergoing rapid change.  相似文献   
825.
826.
827.
The performance of the polymorphic marker systems group-specific component (GC), phosphoglucomutase-1 (PGM), alpha-2-HS-glycoprotein (A2HS), haptoglobin (Hp), and erythrocyte acid phosphatase (EAP) was evaluated on control bloodstains. The major factors considered were: sensitivity of the test system; stability of the marker; laboratory economics of each test; and distinguishing power (Dp) of the system. GC was considered to be the most suitable marker for routine screening because of its high stability and Dp, and the sensitivity of the immunoblotting detection method. PGM and A2HS were the next most valuable markers followed by Hp. EAP could only be considered useful when large amounts of relatively fresh bloodstain were available.  相似文献   
828.
This report describes a collaborative study on typing group-specific component (GC), conducted between the Central Research and Support Establishment and the forensic science laboratories of England, Wales and Northern Ireland. A population study (n=114) was performed. Fifty blood donors were selected to provide a distribution, slightly biased from normal, in favour of the GC 1F-1F and GC 1F-1S phenotypes. A protocol was devised for preparing large bloodstains. The strongest GC bands were obtained from the edge of a stain after the blood had been treated with K+/EDTA. Each laboratory received a representative portion of the large bloodstains for GC typing. Five of the eight laboratories correctly grouped all the bloodstains. No errors directly attitributable to the system were recorded in over 800 tests, indicating that GC in bloodstains can be typed reliably using the combination of isoelectric focusing in ultrathin narrow pH interval gels followed by immunofixation and silver staining.  相似文献   
829.
The microscopic pathology of the liver in fatal cocaine intoxication was studied. Data from cases of cocaine intoxication during the years 1981-1986 were collected and analysed. Thirty cases with a negative past history for intravenous drug abuse, and in which the terminal drug testing revealed solely cocaine or its metabolites, were compared with a control group of nineteen people who had died in motor vehicle accidents, with a terminal negative blood alcohol, negative drug screen and no history of drug abuse. A comparison of liver histology was made along with gross anatomical liver weight. These findings are compared to other studies of hepatotoxicity in drug abuse.  相似文献   
830.
Blood ethanol profiles were determined in experiments with healthy volunteers after they had drunk beer. When 330 ml of light beer (1.8% w/v ethanol) was consumed in 5 min by four men and four women, the average peak blood-alcohol concentration (BAC) reached was 8 mg/100 ml (range 2-11). After nine men had drunk 660 ml of beer (3.0% w/v or 3.6% w/v ethanol) in 25 minutes on an empty stomach, the average peak BAC was 32 mg/100 ml (range 26-44) and 37 mg/100 ml (range 23-54) respectively. When the same two beers were consumed by another nine men together with a meal, the peak BAC was 24 mg/100 ml (range 20-29) and 28 mg/100 ml (range 20-39) respectively. The peak BAC occurred earlier when beer was ingested together with food; mean 32 min (range 30-50) compared with 41 min (range 30-70) with an empty stomach. The rate of disappearance of alcohol from blood (beta-slope) was 12 mg/100 ml/h in the fed state and 15 mg/100 ml/h when subjects were fasted. The apparent volume of distribution of ethanol (Vd) was 0.65 l/kg (SD 0.07) for the empty stomach condition but exceeded unity when beer was ingested together with food. It seems that part of the dose of alcohol when consumed with food never reaches the systemic circulation.  相似文献   
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