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It is essential to identify childhood predictors of adult antisocial personality disorder (APD) to target early prevention. It has variously been hypothesized that APD is predicted by childhood conduct disorder (CD), attention-deficit/hyperactivity disorder (ADHD), or both disorders. To test these competing hypotheses, the authors used data from a single childhood diagnostic assessment of 163 clinic-referred boys to predict future APD during early adulthood. Childhood Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev.; American Psychiatric Association, 1987) CD, but not ADHD, significantly predicted the boys' subsequent APD. An interaction between socioeconomic status (SES) and CD indicated that CD predicted APD only in lower SES families, however. Among children who met criteria for CD, their number of covert but not overt CD symptoms improved prediction of future APD, controlling for SES. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
33.
A number of studies have considered whether background stress affects cardiovascular responses to acute stress tasks. The present study considers the effect of a potent background stressor with a clear onset, namely the terrorist attacks on September 11, 2001. Specifically, the authors investigated differences among 9.5-year-old children tested before (N = 30) and then following (N = 20) the 9/11 attacks. In addition, a majority of these children (N = 37) were retested approximately 1 year later (i.e., before and after 9/11/2002). Children tested directly following 9/11/2001 exhibited significantly greater stroke volume and cardiac output responses to acute stress tasks compared with their responses 1 year later, and this change in reactivity differed significantly from the change in reactivity exhibited by children tested before 9/11/2001 and again 1 year later. These results suggest that a potent background stressor can temporarily heighten some children's cardiovascular responses to subsequent acute stressors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
34.
We present congregating both as a metaphor for describing and modeling multiagent systems (MAS) and as a means for reducing coordination costs in large-scale MAS. When agents must search for other agents to interact with, congregations provide a way for agents to bias this search towards groups of agents that have tended to produce successful interactions in the past. This causes each agent's search problem to scale with the size of a congregation rather than the size of the population as a whole. In this paper, we present a formal model of a congregation and then apply Vidal and Durfee's CLRI framework [24] to the congregating problem. We apply congregating to the affinity group domain, and show that if agents are unable to describe congregations to each other, the problem of forming optimal congregations grows exponentially with the number of agents. The introduction of labelers provides a means of coordinating agent decisions, thereby reducing the problem's complexity. We then show how a structured label space can be exploited to simplify the labeler's decision problem and make the congregating problem linear in the number of labels. We then present experimental evidence demonstrating how congregating can be used to reduce agents' search costs, thereby allowing the system to scale up. We conclude with a comparison to other methods for coordinating multiagent behavior, particularly teams and coalitions.  相似文献   
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A recently proposed argument to explain the improved performance of the eight-point algorithm that results from using normalized data (Chojnacki, W., et al. in IEEE Trans. Pattern Anal. Mach. Intell. 25(9):1172–1177, 2003) relies upon adoption of a certain model for statistical data distribution. Under this model, the cost function that underlies the algorithm operating on the normalized data is statistically more advantageous than the cost function that underpins the algorithm using unnormalized data. Here we extend this explanation by introducing a more refined, structured model for data distribution. Under the extended model, the normalized eight-point algorithm turns out to be approximately consistent in a statistical sense. The proposed extension provides a link between the existing statistical rationalization of the normalized eight-point algorithm and the approach of Mühlich and Mester for enhancing total least squares estimation methods via equilibration. The paper forms part of a wider effort to rationalize and interrelate foundational methods in vision parameter estimation.  相似文献   
37.
Canada is considering the development of a new standard for infant/child life jackets. Eight currently available (approved and non-approved) infant/child life jackets were procured for evaluation. Fifty-six participants were chosen as a sample of convenience from the general public for testing. The life jackets were divided into two groups of four, which were donned on a soft infant manikin procured from the Red Cross. In 224 attempts at donning, only 43 (19%) attempts resulted in the life jacket being donned correctly in less than 1 min. Only one life jacket came close to a good design and passed the life jacket standard for donning time and accuracy. Failure rates were observed across all the participants irrespective of age, gender, experience with children and experience with recreational marine equipment. Accuracy and speed of donning the life jacket were hampered as the number of donning sub-tasks increased. It was concluded that it is possible to design a life jacket that can be donned correctly in under 1 min. The life jacket must be of simple, intuitive design and fall naturally into the anatomical shape of the child. A minimum number of ties, zips and clips should be used in the design, and if such connectors are used they should be color coded or of different shapes and sizes to avoid confusion.  相似文献   
38.
Commercially available quantum dots have been encapsulated in a poly(methyl methacrylate) film and used as a luminescent downshifting layer on cadmium sulfide/cadmium telluride photovoltaic devices. Application of these films has resulted in a relative improvement to the short‐circuit current of over 4% by I–V measurement, with a significant increase in the contribution of short‐wavelength light resulting in 25% of the current available in this part of the spectrum being captured. The films have been shown to be highly scattering and the associated difficulties this provides to external quantum efficiency measurements have been discussed. A range of optical characterisation techniques, particularly laser beam induced current, have been used to probe the effect the films have on a cadmium sulfide/cadmium telluride device. An alternate methodology for performing external quantum efficiency measurements with the quantum dot films has been proposed. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
39.
The aim of this study was to predict biscuit-making quality by using correlations between and, heritabilities of, the most important soft wheat quality characteristics. A full diallele cross was made between six spring wheats. The parents and 30 F 1 hybrids were used as experimental material. Percentage vitreous kernels, breakflour yield, farinograph absorption, farinograph development time and alkaline water retention capacity were highly heritable and were also significantly correlated with sugar-snap biscuit diameter. Selection for these characteristics should lead to improvement of biscuit-making quality. In general, softer kernels and a weak dough with a low water absorption were desirable for good biscuit-making quality.  相似文献   
40.
Many coastal embayments in the Laurentian Great Lakes have been subjected to extensive human physical modification and pollution that has led to the loss of freshwater biodiversity. For example, Hamilton Harbour is a large coastal embayment situated at the western end of Lake Ontario, with a long history of industrial and urban development that has resulted in the loss and degradation of aquatic habitat and the extirpation of several fish species. To restore the fish community in Hamilton Harbour, several attempts have been made to increase apex predator biodiversity by reintroducing native walleye (Sander vitreus). To assess how reintroduced (i.e., stocked) walleye use Hamilton Harbour, we used acoustic telemetry to characterize the residency of individuals within the boundaries of the harbour as well as their seasonal space use, with a focused interest on the spring spawning period. During the 1?yr tracking period tagged walleye spent an average of 357?days (range 135–365?days) within the harbour. Most individuals (12/15) remained within the harbour during the entire spring spawning period, and over half of the tagged fish departed (n?=?7) at the end of summer and beginning of fall. Core use areas appeared to gradually shift more easterly as the seasons progressed from winter to summer. Results from this study indicate that stocked fish are resident within Hamilton Harbour for most of the year, including the reproductive period, which suggests that stocking efforts to re-establish walleye populations may be an effective restoration strategy if recruitment is successful.  相似文献   
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