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Neuromotor reaction times (simple, choice, and decision) were measured when Thyrotropin-releasing hormone (TRH) was administered intravenously to nine healthy men in a double-blind study. Measurements were made of simple reaction time, choice reaction time, and decision time for each subject at various intervals over a 54-hr. period. Given the observed inherent interaction of the drug with the long time used (54 hr.), most analyses were conducted across separate time epochs. Injected subjects showed inhibition in the normal improvement of simple reaction time (which occurs with practice), and they reduced the time required to make a decision. Choice reaction time, however, remained unchanged across the drug-nondrug experimental conditions.  相似文献   
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The experiment investigated the effects of Type A behavior, anger expression, and gender on perceptions of control and heart rate. Jenkins Activity Survey defined Type A and B subjects, categorized as either high or low in anger expression, were asked to recall, image, and generate self-referent statements about angry situations. State anger and heart rate were measured during all of the anger induction conditions, and ratings of imagery vividness and perceptions of control for self and others were taken following the recalled and imaged anger conditions. The results, with both the heart rate and self-report measures, indicated that the effects of the independent variables were interactive and situationally dependent. Type A behavior was associated with increased heart rate in two experimental conditions (mood anger and recalled anger), and, in one instance, this effect was amplified in male subjects (recalled anger). The self-report results yielded interactional effects that most commonly took the form of high anger expression, with male Type A's providing higher ratings of state anger, more vivid anger imagery, and lower perceived self-control ratings than did other categories of subjects. Taken together, these results suggest that anger expressiveness, particularly among males, amplifies the usual reactions attributed to Type A's, and that such effects are mediated by the threat of loss of control. Further, the observed interactive relationships limit the generalizability of A/B differences and raise definitional questions about Type A behavior.  相似文献   
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Correlations were computed between United States per capita consumption of cigarettes and 41 different foods for the years 1964–1977 and 1968–1973. There were significant negative correlations between consumption of cigarettes and sugar. Few other foods showed any relationship to cigarette consumption. These findings corroborate the results of a recent human laboratory study of cigarette smoking and food consumption and a recent animal study of the effects of nicotine on food consumption, taste preferences, and body weight. Taken together, these studies suggest that the inverse relationship between cigarette smoking and body weight may be partially explained by changes in consumption of sweet-tasting high caloric foods.  相似文献   
38.
Neil Tennant 《Studia Logica》1984,43(1-2):181-200
This paper treats entailment as a subrelation of classical consequence and deducibility. Working with a Gentzen set-sequent system, we define an entailment as a substitution instance of a valid sequent all of whose premisses and conclusions are necessary for its classical validity. We also define a sequent Proof as one in which there are no applications of cut or dilution. The main result is that the entailments are exactly the Provable sequents. There are several important corollaries. Every unsatisfiable set is Provably inconsistent. Every logical consequence of a satisfiable set is Provable therefrom. Thus our system is adequate for ordinary mathematical practice. Moreover, transitivity of Proof fails upon accumulation of Proofs only when the newly combined premisses are inconsistent anyway, or the conclusion is a logical truth. In either case Proofs that show this can be effectively determined from the Proofs given. Thus transitivity fails where it least matters — arguably, where it ought to fail! We show also that entailments hold by virtue of logical form insufficient either to render the premisses inconsistent or to render the conclusion logically true. The Lewis paradoxes are not Provable. Our system is distinct from Anderson and Belnap's system of first degree entailments, and Johansson's minimal logic. Although the Curry set paradox is still Provable within naive set theory, our system offers the prospect of a more sensitive paraconsistent reconstruction of mathematics. It may also find applications within the logic of knowledge and belief.  相似文献   
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Neil H. Timm 《Psychometrika》1970,35(4):417-437
Employing simulated data, several methods for estimating correlation and variance-covariance matrices are studied for observations missing at random from data matrices. The effect of sample size, number of variables, percent of missing data and average intercorrelations of variables are examined for several proposed methods.The author is indebted to Professors Leonard A. Marascuilo, Gus W. Haggstrom, especially Henry F. Kaiser for their invaluable suggestions throughout this work. Appreciation is also extended to the Computer Center facility of the University of California at Berkeley for the use of computer time to complete the necessary computations.  相似文献   
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This experiment examines how narrative context affects French subjects' selection of past imperfective (imparfait) vs. perfective inflections with different predicate types. Adults and 10-year-old children were asked to inflect verbs presented in their written infinitive form in two conditions: (a) in isolated sentences; (b) embedded in the beginning, middle, or end of narratives. Regardless of conditions, the adults rarely used theimparfait with punctual resultative predicates. In both conditions, the frequency ofimparfait was high with durative predicates, particularly with aresultative ones, but it varied with position in the narratives, being highest at the beginning and lowest at the end. Although the children also used the imparfait frequently with durative predicates, they overgeneralized it to punctual resultative ones, regardless of conditions and of positions. These results show that adult uses of the imperfective/perfective distinction are determined by both predicate properties and grounding in narrative context. The children are less sensitive to some predicate properties than the adults and they do not differentiate imperfective/perfective aspect consistently as a function of discourse context.  相似文献   
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