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161.
Transparent layer constancy   总被引:1,自引:0,他引:1  
Perceived transparency was studied as a constancy problem. In the episcotister (E-) model of scission, luminances are partitioned into layer and background components; four luminances determine values of two layer parameters that specify constancy of a transparent layer on different backgrounds. The E-model was tested in an experiment in which 12 Ss matched 24 pairs of four-luminance patterns by adjusting two luminances of the comparison pattern. Both the standard and the comparison were perceived as a transparent layer on a checkerboard. The E-model predicts matches when layer values are identical in the two patterns. One parameter was constant, constraining the adjustment along the second dimension. Obtained values corresponded well with E-predictions. Alternative models based on local luminance or average contrast ratios accounted for less variability. Results indicate that transparency models should utilize luminance, not reflectance, as the independent variable.  相似文献   
162.
In rats, pretraining ip administration of the central benzodiazepine receptor antagonist, flumazenil (5.0 mg/kg), or of the inverse agonist, n-butyl-beta-carboline-3-carboxylate (BCCB) (0.2 or 0.5 mg/kg), facilitated retention of a step-down inhibitory avoidance task; the central agonists, clonazepam and diazepam (0.4 or 1.0 mg/kg), had an opposite effect, and the peripheral agonist, 4'-chlordiazepam (1.25 or 6.25 mg/kg), was without effect. Pre- but not post-training flumazenil (2.0 mg/kg) blocked the effect of BCCB (0.5 mg/kg), clonazepam (1.0 mg/kg), or diazepam (1.0 mg/kg) given also pretraining. The post-training administration of all of these drugs had no effect on retention of the avoidance task. Flumazenil (5.0 mg/kg) and BCCB (0.5 mg/kg), given before training, enhanced retention test performance of habituation to a buzzer but not of habituation to an open field. In the three tasks studied, none of the drugs used had any appreciable effect on training session parameters. These results suggest that there is an endogenous mechanism mediated by benzodiazepine agonists, sensitive to inverse agonists, that normally down-regulates acquisition of certain behaviors; this mechanism becomes activated only when the tasks involve or occur with a certain degree of stress or anxiety (i.e., inhibitory avoidance or habituation to the buzzer) and not in less stressful or anxiogenic tasks (i.e., habituation to an open field).  相似文献   
163.
The relationship between sex role flexibility and prosocial behavior among preschool children was investigated. Subjects included 16 boys and 18 girls, ranging in age from 36 to 60 months, from intact families of the upper middle class. A nonhierarchical multiple regression analysis was undertaken to determine the contributions of the predictor variables of sex, age, IQ, and sex role flexibility, as well as their interactions with prosocial behavior (criterion variable). Results indicated that while the overall regression model was not significant, the variable of Sex × Sex Role Flexibility did contribute significantly to the model. Inspection of the correlation coefficients associated with this variable revealed that while sex role flexibility and prosocial behavior among boys were significantly and positively related, among girls no significant relationship was found.  相似文献   
164.
It was hypothesized that older widows (N=309) who had been care givers to their husbands would have undertaken a greater number of household responsibilities than had women who had not been care givers. Findings indicated that, prior to the husband's death, more traditionally male and more traditionally female tasks were performed by the care-giving wives (n=158). This was particularly true in the case of Alzheimer's care givers (n=21). More importantly, widows' present feelings of competence were related to undertaking household responsibilities, with those who had been care givers expressing significantly higher levels of competence.  相似文献   
165.
Prime Minister Yitzhak Rabin's assassination has less of a lasting impact on the Israeli public's political values, beliefs and attitudes than might have been anticipated from the magnitude of the event and intensity of the immediate responses. Why did the assassination have such a short-lived effect? This article considers the puzzle as a specific case of the broader phenomenon of collective political trauma and its consequences for values, beliefs and attitudes held by the mass public toward issues that it associates with the traumatic event. The article offers six deductively inferred hypotheses that describe, explain and link affective, cognitive and behavioral aspects of collectively experienced trauma. These hypotheses form a pre-theory explaining the perseverence of core political cognitions, even in the face of a considerable challenge to their validity and relevance.  相似文献   
166.
167.
Relation algebras from cylindric and polyadic algebras   总被引:1,自引:0,他引:1  
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168.
169.
Strong representability of fork algebras, a set theoretic foundation   总被引:1,自引:0,他引:1  
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170.
Current status of the Rorschach Inkblot Method   总被引:1,自引:0,他引:1  
The current scientific, clinical, and professional status of the Rorschach Inkblot Method (RIM) is reviewed with respect to its psychometric properties, the applied purposes it can be expected to serve, the extent of its use, and the nature of prevailing attitudes toward it. Available evidence indicates that the RIM is a psychometrically sound measuring instrument that provides valid assessments of personality characteristics and can facilitate differential diagnosis and treatment planning and evaluation. The RIM continues as in the past to be widely used by both clinicians and researchers. However, the esteem in which it is held by practitioners, who are generally agreed that clinical psychologists should be competent in Rorschach assessment, is not universally shared by academicians, many of whom presently question the future place of Rorschach training in graduate education.  相似文献   
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