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811.
Numerous studies have shown that alcohol intake causes neuropsychological disorders that affect various brain structures. The ?premature ageing? hypothesis proposes that the brain areas of alcoholics undergo deterioration similar to that observed in old age. We investigated whether alcohol abuse by young people (binge drinking) causes alterations comparable to some found in elderly people. Ninety-one people were divided into four groups: a) young people who abused alcohol; b) young people who drank alcohol in moderation; c) young people who did not drink alcohol; and d) elderly adults without any significant cognitive deterioration. All of them were assessed with a neuropsychological battery. We observed some similarities in the results obtained by young drinkers and the elderly participants, which would provide some support for the hypothesis of premature aging. The tasks that young drinkers performed worse were those related to executive functions, in which the prefrontal cortex plays an essential role. We also found differences between the two groups of young drinkers (moderate and high consumption), which leads us to believe that the amount of alcohol consumed and the pattern of consumption are factors to consider in relation to cognitive impairment.  相似文献   
812.
People are strongly motivated to feel accepted by others. Yet when faced with acute peer rejection they often aggress against the very peers they desire acceptance from, which may lead to further rejection. The present experiment tests three potential mediators of aggressive responses to acute peer rejection in the critical developmental stage of early adolescence. Participants (N=185, M(age)=11.5 years) completed personal profiles that were allegedly evaluated online by peers. After receiving negative or neutral peer feedback, participants could aggress against the same peers who had evaluated them. Rejected participants attributed more hostile intent to the peers, were angrier, showed a greater reduction in state self-esteem, and were more aggressive. Mediational analyses showed that hostile intent attributions mediated the acute peer rejection-aggression relationship, whereas increases in anger and decreases in state self-esteem did not. Thus, acute peer rejection evokes hostile intent attributions that, in turn, lead to aggressive reactions.  相似文献   
813.
814.
We relate Thurstonian models for paired comparisons data to Thurstonian models for ranking data, which assign zero probabilities to all intransitive patterns. We also propose an intermediate model for paired comparisons data that assigns nonzero probabilities to all transitive patterns and to some but not all intransitive patterns.There is a close correspondence between the multidimensional normal ogive model employed in educational testing and Thurstone's model for paired comparisons data under multiple judgment sampling with minimal identification restrictions. Alike the normal ogive model, Thurstonian models have two formulations, a factor analytic and an IRT formulation. We use the factor analytic formulation to estimate this model from the first and second order marginals of the contingency table using estimators proposed by Muthén. We also propose a statistic to assess the fit of these models to the first and second order marginals of the contingency table. This is important, as a model may reproduce well the estimated thresholds and tetrachoric correlations, yet fail to reproduce the marginals of the contingency table if the assumption of multivariate normality is incorrect.A simulation study is performed to investigate the performance of three alternative limited information estimators which differ in the procedure used in their final stage: unweighted least squares (ULS), diagonally weighted least squares (DWLS), and full weighted least squares (WLS). Both the ULS and DWLS show a good performance with medium size problems and small samples, with a slight better performance of the ULS estimator.This paper is based on the author's doctoral dissertation; Ulf Böckenholt, advisor. The final stages of this research took place while the author was at the Department of Statistics and Econometrics, Universidad Carlos III de Madrid. The author is indebted to Adolfo Hernández for stimulating discussions that helped improve this paper, and to Ulf Böckenholt and the Associate Editor for a number of helpfulsuggestions to a previous draft.  相似文献   
815.
Neighborhood influences on children and youth are the subjects of increasing numbers of studies, but there is concern that these investigations may be biased, because they typically rely on census-based units as proxies for neighborhoods. This pilot study tested several methods of defining neighborhood units based on maps drawn by residents, and compared the results with census definitions of neighborhoods. When residents' maps were used to create neighborhood boundary definitions, the resulting units covered different space and produced different social indicator values than did census-defined units. Residents' agreement about their neighborhoods' boundaries differed among the neighborhoods studied. This pilot study suggests that discrepancies between researcher and resident-defined neighborhoods are a possible source of bias in studies of neighborhood effects.  相似文献   
816.
The substantial number of persons with mental illness encountered in many sectors of the criminal justice system has spurred actors from various agencies within that system to take actions aimed at reducing the growth of this population. These actions have included the development of specialty police units, jail diversion programs, and other mechanisms for channeling persons with mental illness out of the criminal justice system and into mental health treatment. The courts, too, have become involved in this effort with the recent development of the "mental health court," the latest of the "specialty" or "problem solving courts." These courts have not been without their critics, however, nor are they the only feasible approach to court-based diversion. This paper identifies and explores a range of options for structuring the relationship between criminal courts and local mental health systems. Beginning with a discussion of the rationale motivating the development of mental health courts, two alternatives to this specialty court model are discussed. One involves judges dealing with defendants having mental illness and substance abuse on a case-by-case basis. The other takes advantages of linkages that may already exist between most courts and the mental health providers who conduct their forensic assessments, expanding the role of these providers to serve as boundary spanners between courts and the components of local mental health systems. Regardless of the model adopted, however, appropriate linkages must exist between the courts and relevant providers. A case study is provided that demonstrates how the status of a locale's linkages can be evaluated and how the information derived from such evaluation can be used to improve the linkages between police, courts, and health and human services agencies.  相似文献   
817.
818.
A substantial amount of recent work in natural language generation has focused on the generation of 'one-shot' referring expressions whose only aim is to identify a target referent. Dale and Reiter's Incremental Algorithm (IA) is often thought to be the best algorithm for maximizing the similarity to referring expressions produced by people. We test this hypothesis by eliciting referring expressions from human subjects and computing the similarity between the expressions elicited and the ones generated by algorithms. It turns out that the success of the IA depends substantially on the 'preference order' (PO) employed by the IA, particularly in complex domains. While some POs cause the IA to produce referring expressions that are very similar to expressions produced by human subjects, others cause the IA to perform worse than its main competitors; moreover, it turns out to be difficult to predict the success of a PO on the basis of existing psycholinguistic findings or frequencies in corpora. We also examine the computational complexity of the algorithms in question and argue that there are no compelling reasons for preferring the IA over some of its main competitors on these grounds. We conclude that future research on the generation of referring expressions should explore alternatives to the IA, focusing on algorithms, inspired by the Greedy Algorithm, which do not work with a fixed PO.  相似文献   
819.
The current study tested whether the perception of angry faces is cross-culturally privileged over that of happy faces, by comparing perception of the offset of emotion in a dynamic flow of expressions. Thirty Chinese and 30 European-American participants saw movies that morphed an anger expression into a happy expression of the same stimulus person, or vice versa. Participants were asked to stop the movie at the point where they ceased seeing the initial emotion. As expected, participants cross-culturally continued to perceive anger longer than happiness. Moreover, anger was perceived longer in in-group than in out-group faces. The effects were driven by female rather than male targets. Results are discussed with reference to the important role of context in emotion perception.  相似文献   
820.
In this study, the relationship between face recognition and different facial encoding strategies was investigated. Children (6-8 years, N= 134) participated in both a face recognition task and an encoding task. During the recognition task, they saw 7 target faces in an eyewitness context (video) or in a neutral context (static black and white slides) which they later had to recognize from a set of 21 faces. On the encoding task, the same children had to categorize new faces (schematic and photorealistic) into two categories. The construction of the categories allowed participants to encode the faces either analytically (by focusing on a single attribute) or holistically (in terms of overall similarity). The results showed that face recognition was better in the social than in the neutral context. In the neutral context, only holistic encoding was connected to better face recognition. In the social context, children seemed to use not only information about the faces but also information about the persons.  相似文献   
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