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991.
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In a test of predictions derived from an identity-analytic model of self-presentational behavior, individuals who privately endorsed positive or negative attitudes about sexual behavior were asked to deliver a prosexuality speech while alone, while watched by observers, or while being watched by observers who questioned the morality of the subject’s actions. Subsequent attitude measures indicated that the subjects who initially adopted negative attitudes justified their behavior by expressing more favorable attitudes about sexuality, but only when no audience witnessed their speech. When an audience was present, these individuals emphasized their lack of choice. In contrast, subjects who privately endorsed positive attitudes publicly expressed less favorable attitudes when their morality was challenged by the observers. These findings suggest that attitude change following counterattitudinal behavior (a) stems from private image-maintenance needs as well as public self-presentational concerns, and (b) is sometimes designed to secure an image of morality as well as an image of consistency.  相似文献   
994.
This study examined parent-child interactions and parent characteristics in families of nonproblem children and attention deficit hyperactivity disorder (ADHD) children with lower (ADHD-LOD) and higher (ADHD-HOD) levels of oppositional-defiant behavior. Families of ADHD children were recruited from a parent training program. Observed and parent-reported child behavior problems were highest in the ADHD-HOD group. Observed parent behavior revealed few differences, but daily reports indicated that parents in both ADHD groups used more negative-reactive and fewer positive parenting strategies than control parents. Maternal psychological functioning differed between the ADHD and nonproblem groups, but not between the two ADHD groups. Fathers of ADHD-HOD children reported more psychological disturbance than controls. Parenting self-esteem was lowest in the ADHD-HOD group and highest in the nonproblem group. The results support the LOD and HOD distinction, but also suggest that, although certain difficulties are more common in the families of ADHD-HOD children, families of ADHD-LOD children also differ from controls on a number of dimensions.This research was supported by grants from the Medical Research Council of Canada and the British Columbia Health Research Foundation. Appreciation is extended to Josie Geller, Kim Behrenz, Susan Greaves, and Sonia Pietzsch who assisted with data collection and coding, and to the families who generously gave their time to participate in the research. Thanks also to two anonymous reviewers for their comments.  相似文献   
995.
996.
The aim of this article is to review and evaluate behavioral and physiological measurement techniques frequently used to assess dental anxiety and fear in children. Attention is given to the data collected, the empirical findings obtained, and the availability of normative data. The main focus, however, is on the reliability and validity. Results show that all questionnaires are open to criticism. Of the behavioral measures, Melamed's Behavior Profile Rating Scale is to be preferred to Frankl's Rating Scale, Venham Rating Scales, and Visual Analogue Scales. The main reasons are that Melamed's BPRS measures the behavior of the child more precisely and that it has superior psychometric properties. Furthermore, because of their practical, conceptual, and psychometric problems, physiological measures at this stage are found to be less appropriate for assessing dental fear in children. It is concluded that a behavioral measure is not always the ideal, but often the only available technique for assessing dental fear in children.  相似文献   
997.
998.
Modal Foundations for Predicate Logic   总被引:1,自引:0,他引:1  
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999.
The potential for communication through the kinesthetic aspect of the tactual sense was examined in a series of experiments employing Morse code signals. Experienced and inexperienced Morse code operators were trained to identify Morse code signals that were delivered as sequences of motional stimulation through up-down displacements (roughly 10 mm) of the fingertip. Performance on this task was compared with that obtained for both vibrotactile and acoustic presentation of Morse code using a 200-Hz tone delivered either to the fingertip through a minishaker or diotically to the two ears under headphones. For all three modalities, the ability to receive Morse code was examined as a function of presentation rate for tasks including identification of single letters, random three-letter sequences, common words, and sentences. Equivalent word-rate measures (i.e., product of percent correct scores and stimulus presentation rate) were nearly twice as high for auditory presentation as for vibrotactile stimulation, which in turn was about 1.3 times that for motional stimulation. The experienced subjects outperformed the inexperienced subjects by amounts that increased with task complexity. For example, the former were able to receive sentences at 18 words/min with motional stimulation, whereas the latter, following 75 h of training, were unable to perform this task. The present results and those of other research with tactual communication systems are compared, particularly regarding estimates of information-transfer rates.  相似文献   
1000.
Reasoning about update logic   总被引:1,自引:0,他引:1  
Logical frameworks for analysing the dynamics of information processing abound [4, 5, 8, 10, 12, 14, 20, 22]. Some of these frameworks focus on the dynamics of the interpretation process, some on the dynamics of the process of drawing inferences, and some do both of these. Formalisms galore, so it is felt that some conceptual streamlining would pay off.This paper is part of a larger scale enterprise to pursue the obvious parallel between information processing and imperative programming. We demonstrate that logical tools from theoretical computer science are relevant for the logic of information flow. More specifically, we show that the perspective of Hoare logic [13, 18] can fruitfully be applied to the conceptual simplification of information flow logics.  相似文献   
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