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911.
912.
In experiments that involve contact with adhesion between two surfaces, as found in atomic force microscopy or nanoindentation, two distinct contact force (P) vs. indentation-depth (h) curves are often measured depending on whether the indenter moves towards or away from the sample. The origin of this hysteresis is not well understood and is often attributed to moisture, plasticity or viscoelasticity. Here we report experiments that show that hysteresis can exist in the absence of these effects, and that its magnitude depends on surface roughness. We develop a theoretical model in which the hysteresis appears as the result of a series of surface instabilities, in which the contact area grows or recedes by a finite amount. The model can be used to estimate material properties from contact experiments even when the measured P-h curves are not unique.  相似文献   
913.
Integrating evolutionary and social representations theories, the current study examines the relationship between perceived disease threat and exclusionary immigration attitudes in the context of a potential avian influenza pandemic. This large‐scale disease provides a realistic context for investigating the link between disease threat and immigration attitudes. The main aim of this cross‐sectional study (N = 412) was to explore mechanisms through which perceived chronic and contextual disease threats operate on immigration attitudes. Structural equation models show that the relationship between chronic disease threat (germ aversion) and exclusionary immigration attitudes (assimilationist immigration criteria, health‐based immigration criteria and desire to reduce the proportion of foreigners) was mediated by ideological and normative beliefs (social dominance orientation, belief in a dangerous world), but not by contextual disease threat (appraisal of avian influenza pandemic threat). Contextual disease threat only predicted support for health‐based immigration criteria. The conditions under which real‐life disease threats influence intergroup attitudes are scrutinized. Convergence and dissimilarity of evolutionary and social representational approaches in accounting for the link between disease threat and immigration attitudes are discussed. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
914.
Visual evidence     
Visual and other demonstrative evidence has become increasingly prevalent in American and other courtrooms in recent years. However, there have been relatively few experimental studies of the effects of this kind of evidence in legal settings. As a consequence, little is known about when and how it affects legal decision making. In this article, I survey the extant research, including studies of photographs, videos, computer animations, and PowerPoint displays. The research shows that visual evidence affects legal decisions in some circumstances but not in others. It also indicates that visual evidence sometimes enhances legal judgment by improving recall and understanding but sometimes impairs judgment by prompting undue emotional responses, cognitive and perceptual biases, and/or peripheral processing. The limitations of the research are discussed, and directions for future research are suggested.  相似文献   
915.
In spite of the efficacy of the psychodynamic psychotherapies, the number of young psychiatric residents interested in psychodynamic therapies is decreasing. Our psychoanalytical group, Genden (Genève-Denver), explored the possible reasons for psychiatric residents' hesitation to get psychoanalytic training. Five psychoanalytical psychotherapists met weekly for a year in order to debate that question, focusing on personal feedbacks from all of our 100 residents in psychiatry working with us for at least 4 years. Following the residents' responses, our focus group proposed ten commonsense feedbacks for psychoanalysts regarding stimulating young psychiatric residents' interest in psychoanalytic approaches.  相似文献   
916.
The Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV; American Psychiatric Association, 1994) specifies a developmental relationship between oppositional defiant disorder (ODD) and conduct disorder (CD). Evidence for this link is mixed, however, and recent studies suggest that different symptom dimensions in ODD may have different outcomes. The authors examined links between ODD, CD, and their young adult outcomes in the Great Smoky Mountains Study (E. J. Costello et al., 1996), a longitudinal data set with over 8,000 observations of 1,420 individuals (56% male) covering ages 9-21 years. ODD was a significant predictor of later CD in boys but not in girls after control for comorbid CD and subthreshold CD symptomatology. Transitions between ODD and CD were less common than anticipated, however, particularly during adolescence. The authors examined characteristics and outcomes of children with pure ODD, pure CD, and combined CD/ODD. Alongside many similarities in childhood and adolescent correlates, key differences were also identified: CD largely predicted behavioral outcomes, whereas ODD showed stronger prediction to emotional disorders in early adult life. Factor analysis identified irritable and headstrong dimensions in ODD symptoms that showed differential prediction to later behavioral and emotional disorders. Overall, the results underscore the utility of retaining separate ODD and CD diagnoses in DSM-V.  相似文献   
917.
The kinematics of stair climbing were examined to test the assertion that relative timing is an invariant feature of human gait. Six male and four female subjects were video-recorded (at 60 Hz) while they climbed a flight of stairs 10 times at each of three speeds. Each gait cycle was divided into three segments by the maximum and minimum angular displacement of the left knee and left foot contact. Gentner's (1987) analysis methods were applied to the individual subject data to determine whether the duration of the segments remained a fixed proportion of gait cycle duration across changes in stair-climbing speed. A similar analysis was performed using knee velocity maxima to partition the gait cycle. Regardless of how the gait cycle was divided, relative timing was not found to remain strictly invariant across changes in speed. This conclusion is contrary to previous studies of relative timing that involved less conservative analysis but is consistent with the wider gait literature. Strict invariant relative timing may not be a fundamental feature of movement kinematics.  相似文献   
918.
Stability of inhibited/uninhibited temperament was assessed using 1,795 Mauritian children tested at ages 3, 8, and 11 years. Children were divided into uninhibited, middle, and inhibited groups at each age based on social behavior. Results indicated that, relative to uninhibited children (1) those inhibited at age 3 obtained larger inhibition scores at age 8 (p< .0001), (2) those inhibited at age 8 obtained larger inhibition scores at age 11 (p< .002), and (3) those remaining inhibited from ages 3 to 8 obtained larger inhibition scores at age 11 (p< .002). Relative to children who changed classification from ages 3 to 8, those remaining inhibited obtained larger inhibition scores (p< .05) and those remaining uninhibited obtained smaller inhibition scores (p< .015) at age 11. Inhibition scores tended to be higher in females by age 11. Results remained regardless of ethnicity. The results provide some support that inhibited/uninhibited temperament remains stable from ages 3 to 8 and may continue to age 11. The results suggest cross-cultural generalizability of these findings with implications regarding the development of anxiety disorders in the Mauritian population. The efforts of Cyril Dalais, Brian Bell, Athenea Chiriaca, and all the local members of the longitudinal study, the Mauritius Joint Child Health Project, are gratefully acknowledged. We are also especially thankful to Drs. Michael E. Dawson, David Walsh, and Bill McClure for their helpful comments and suggestions.The data used in this study were collected while the project was supported by the Medical Research Council (UK), the Wellcome Trust (UK), and the Mauritian government. The data were analyzed and findings written as part of the first author's dissertation work under the support of the NIMH Pre-doctoral Individual National Research Service Award and a USC Dissertation Fellowship Award.  相似文献   
919.
This study begins the process of examining clinical psychologists' competence in dealing with lesbian clients by assessing their attitudes to lesbians and lesbianism. Attitudinal questionnaires were sent to 200 chartered clinical psychologists and 69 (34.5%) were returned. Respondents displayed generally positive attitudes, with only two out of 12 attitudinal items failing to attract attitudinally positive responses from more than three-quarters of the sample. Yet, because of the possible unrepresentativeness of the sample and the potentially tenuous attitude–behaviour link, it is recommended that consideration of lesbian issues should be explicitly addressed in clinical psychology training.  相似文献   
920.
This exploratory study investigates the effect of music on the perceived characteristics of a commercial listening environment and on customers' purchase intentions therein. Three musical styles and also no music were played in a student cafeteria over the course of 4 days. Subjects' responses to a questionnaire indicated that different musical styles had different effects on the perceived characteristics of the cafeteria, and that classical music was associated with subjects being prepared to pay the most for food items on sale therein. There was also some indication that classical and pop music might have increased actual sales in the cafeteria, as compared with easy listening and silence. These results are discussed in terms of their implications for both commercial practice and our theoretical understanding of music and consumer behavior.  相似文献   
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