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61.
Regional cerebral blood flow (rCBF) may be measured with inhalation techniques that use end-expired values of radioactivity to estimate the isotope concentration in arterial blood. These end-expired data are used as an input function in a mathematical equation to derive rCBF. End-expired air is assumed normally to be in equilibrium with the arterial blood at the alveolar surface of the lung during regular (passive) breathing; this assumption may not be valid during continuous phonation. We therefore have analyzed breathing (inhalation/exhalation) patterns and end-expired radioactivity (133Xe) during (1) speaking, (2) singing, and (3) humming of the national anthem, and also during (4) passive breathing. Statistically significant differences in breathing patterns were measured between a group of nonmusicians and two groups of musicians (singers) during the phonation tasks: The nonmusicians breathed more often (and more rapidly) and exhibited less variability in their breathing patterns than did the musicians. Notwithstanding these differences, the shapes of smoothed functions derived from the end-expired values were not influenced appreciably during phonation (except possibly during talking). The latter finding suggests that estimates of rCBF derived with these data should not be confounded seriously because of the continuous phonation.  相似文献   
62.
This study compared the predictive validity of two types of overall assessment center ratings (clinical and mechanical) and two types of performance ratings (supervisor and subordinate). Data were gathered on approximately 50 law enforcement agency managers over a four-year time span. Results indicated that clinical predictions were not significantly better than mechanical ones and that prior performance ratings were better predictors of future performance ratings than were assessment centers. Further, dimension ratings within the assessment center were found to be unrelated to ratings of the same dimensions on the job four years later, supporting the notion of subtle criterion contamination (Klimoski & Strickland, 1977) and raising questions about the central assumptions underlying the assessment center approach.  相似文献   
63.
Several theories have been presented that predict differences between women and men in attitudes toward the environment due to differences in sex roles. Research on which these theories can be tested has tended to examine general environmental concern, and the results have generally been weak and inconclusive. Using an approach suggested in the literature, this study examines sex differences in concern and knowledge, using multi-item scales for each, about one environmental issue — acid rain. The results contradict the theories being tested, however: if there is a sex difference, men are found to be more concerned and knowledgeable about the environmental problem.  相似文献   
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A major home improvement chain located primarily in the western United States initiated the use of thePersonnel Selection Inventory, a written integrity test, as part of its pre-employment hiring process. For two years only, those job applicants who passed this test and other pre-employment criteria were hired by the chain. Following the introduction of the inventory, there was: (1) a 50% reduction in the number of employee terminations for theft, illegal drug use, and violence over a five year period and (2) a savings in shrinkage losses that amounted to over two million dollars over a two year period.  相似文献   
66.
The influence of alcohol and loud music on analytic versus holistic processing was examined in classification, concept learning, and embedded figures tasks. In the classification task, loud music reduced analytic responding by individuals who had consumed alcohol and increased analytic responding by individuals who had received placebo drinks. Alcohol also decreased the speed with which individuals were able to generate analytic responses in the classification task and decreased analytic performance on the embedded figures test. Alcohol slowed the rate of learning in the concept-learning task but did not lead to less analytic responding in that task. The results are consistent with the idea that alcohol slows the rate of information processing, particularly in tasks requiring visual analysis of stimuli.  相似文献   
67.
The psychophysiological responses of heart rate (HR), systolic and diastolic blood pressure, skin conductance level and forehead electromyogram were compared during: rest, mental arithmetic and combat sounds of gradually increasing intensity for five groups of Ss: Vietnam veterans with post-traumatic stress disorder (PTSD); Vietnam veterans without PTSD but with comparable levels of combat experience; Vietnam veterans with other psychiatric disorders; Vietnam-era veterans; and nonveteran phobics. HR response to low-intensity combat sounds provided good discrimination between veterans with PTSD and the other groups and seems to resemble a conditioned emotional response.  相似文献   
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Three students with moderate handicaps were taught to initiate and expand on conversational topics. The teaching procedure used stimuli generated from actual conversations with nonhandicapped peers. Generalization was assessed by audiotaping conversations between the handicapped students and their peers in natural school contexts without adult supervision. Results indicated that training generalized to natural contexts. These results were socially validated by undergraduate special education students, who rated tapes of two of the students' conversations during training phases as more socially competent than during baseline. Results are discussed in terms of the evaluation of complex social behavior as multioperant behaviors.  相似文献   
70.
The Social Relations Model: An integrative method for personality research   总被引:1,自引:0,他引:1  
As outlined by Snyder and Ickes (1985), the study of personality can be undertaken using one of three research approaches dispositional, situational, and interactive We show how the Social Relations Model provides an integrative method to estimate simultaneously dispositional, situational, and interactive effects Reviewed are component approaches to the study of personality The Social Relations Model is shown to be a component model (a special case of generalizability theory) applied in a social interaction context In the model, dispositional, situational, and interactive effects are termed actor, partner, and relationship effects, respectively The Social Relations Model can be used to answer a number of important issues in personality research The model can be used to assess reliability, measure the validity of self-ratings, and validate self-report inventories The model requires special designs in winch each person interacts with multiple partners Empirical examples are presented in which social anxiety, sex role inventories, and self-disclosure are studied  相似文献   
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