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51.
Exteroceptive control of response under delayed reinforcement   总被引:3,自引:3,他引:0       下载免费PDF全文
Three white rats, after 50 continuous reinforcements, were exposed successively, under dim illumination, to reinforcement delays of 1, 3, 5, 7.5, 10, 15, and 20 sec, with prolonged training at the 20-sec level. Behavior was maintained at each level, and an increase in interval was accompanied by an increase in post-reinforcement pause. Subsequently, under both 20- and 30-sec delays, the animals were tested during half of each daily session to determine the effect of introducing darkness during each delay interval. The result of this stimulus “support” was to regularize and increase response rate for each animal at both interval values.  相似文献   
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In this paper I discuss Husserl's solution of the problem of imaginary elements in mathematics as presented in the drafts for two lectures hegave in Göttingen in 1901 and other related texts of the same period,a problem that had occupied Husserl since the beginning of 1890, whenhe was planning a never published sequel to Philosophie der Arithmetik(1891). In order to solve the problem of imaginary entities Husserl introduced,independently of Hilbert, two notions of completeness (definiteness in Husserl'sterminology) for a formal axiomatic system. I present and discuss these notionshere, establishing also parallels between Husserl's and Hilbert's notions ofcompleteness.  相似文献   
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This study analyzed the relationship between terrorist threat and discrimination, operationalized by support for retributive justice against Islamic groups suspect of terrorist crimes. Two experimental studies were performed. Study 1 (N = 215) showed that the terrorist threat against the ingroup raises the support for the retributive procedures through the dehumanization of the outgroup. Study 2 (N = 304) analyzed how the mediating role of dehumanization in the relationship between terrorist threat and support for retributive justice is moderated by right‐wing authoritarianism (RWA). In addition, the study aimed to verify if the dehumanization of outgroup and RWA could explain the relationship between terrorist threat and discrimination of Muslim immigrants. The results indicated that adherence to RWA favors dehumanization of the outgroup and, consecutively, the discrimination, operationalized as support for the use of retributive justice. The adherence to RWA has been identified as the mechanism that explains the discrimination against Muslim immigrants.  相似文献   
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This study assesses the retractions of scientific articles in engineering journals indexed on the Web of Science from 1945 to 2015. The data set was built based on documents containing the keywords retracted, retraction, withdrawal, or redress. We used database exploration techniques, including Structured Query Language and analysis of variance, for data analysis. We analyzed 238 retractions published by 117 journals. The most common reason for retraction was unethical research, and higher impact factors journals tended to publish more retractions. In conclusion, most of the analyzed retractions were the result of unethical research and were retracted by editors.  相似文献   
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The authors' purpose was to evaluate bilateral ankle intrinsic stiffness in subcortical poststroke subjects. Ten subcortical poststroke subjects and 10 healthy controls participated in this study. The ankle passive stiffness at 3 different speeds and the electromyographic activity of the soleus, the gastrocnemius, and the tibialis anterior muscles of poststroke contralesional (CONTRA) and ipsilesional (IPSI) limbs and of one limb of healthy subjects were assessed. Ankle electromyographic activity was collected to ensure that reflexive or voluntary muscle activity was not being elicited during the passive movements. A significant interaction was observed between the effects of the limb (IPSI vs. CONTRA vs. control) and ankle position, F(4, 28) = 3.285, p = .025, and between the effects of the limb and the velocity of stretch, F(2, 14) = 4.209, p = .037. While increased intrinsic stiffness was observed in the CONTRA limb of poststroke subjects at ankle neutral position when the passive stretch was applied with a velocity of 1°/s (p = .021), the IPSI limb of poststroke subjects presented increased stiffness at 20º of plantar flexion when the stretch was applied with a velocity of 5°/s (p = .009) when compared to healthy group. Subcortical poststroke subjects present increased intrinsic stiffness in both the CONTRA and IPSI limbs in specific ankle amplitudes.  相似文献   
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