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51.
Abstract

The dependence of the normal-state resistivity, resistive superconducting transition (T c, ΔT c), and of the upper critical-field slope (dH c2/dT|T=Tc) on density has been investigated for several YBa2Cu3O9-x(x?2.1) samples. The resistivity decreases rapidly with increasing density, whereas T c and ΔT c are rather insensitive to a change in density. dH c2/dT|Tc depends sensitively on the preparation conditions. The implications of these results both for the evaluation of the parameters relevant to the understanding of the nature of superconductivity and for the technological applications of granular superconductors are briefly discussed.  相似文献   
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Immigrants' sense of self can be derived both from being members of their ethnic in‐group and their country of residence. We examined how the ways in which immigrant adolescents integrate these self‐views in relation to academic success in German schools. Students describe themselves at school and when with family. Using a standardized literacy performance test, analyses revealed that immigrants whose school‐related self‐view did not include Germany were less successful: Students who described their self as including both aspects of their ethnic group and Germany, and students who saw themselves predominantly as German, outperformed students with purely ethnic school‐related selves. As expected, though, an ethnic family‐related self‐view did not have a negative impact on scholastic achievements.  相似文献   
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Studying moderators of intervention effects is essential to elucidate what works for whom. The present study investigated whether child personality moderates short‐term and follow‐up effects of an individualised preventive school‐based intervention for children with externalising behaviour. The sample consisted of 48 schools, with 264 fourth‐grade children displaying externalising behaviour (Mage = 10.2 years), randomly assigned to the intervention (n = 191) or no intervention control (n = 73) condition. Teachers and children reported at pretest, posttest and follow‐up test about reactive and proactive aggression. Child personality was assessed by teachers at pretest. Child conscientiousness moderated short‐term intervention effects, indicating that more organised and planful children benefited more from the intervention. Child extraversion moderated both short‐term and follow‐up intervention effects, with low extraverted children showing larger effects. These results affirm the importance of including personality as moderator of intervention effects in future studies, as interventions adapted to specific child traits might yield larger effects. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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Berislav Marušić 《Synthese》2013,190(12):1977-1999
If we hold that perceiving is sufficient for knowing, we can raise a powerful objection to dreaming skepticism: Skeptics assume the implausible KK-principle, because they hold that if we don’t know whether we are dreaming or perceiving p, we don’t know whether p. The rejection of the KK-principle thus suggests an anti-skeptical strategy: We can sacrifice some of our self-knowledge—our second-order knowledge—and thereby save our knowledge of the external world. I call this strategy the Self-Knowledge Gambit. I argue that the Self-Knowledge Gambit is not satisfactory, because the dreaming skeptic can avail herself of a normative counterpart to the KK-principle: When we lack second-order knowledge, we should suspend our first-order beliefs and thereby give up any first-order knowledge we might have had. The skeptical challenge is essentially a normative challenge, and one can raise it even if one rejects the KK-Principle.  相似文献   
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Although achievement goal and expectancy-value theories are both dominant in the achievement motivation literature, the relation between goals and expectancy-value variables in predicting achievement-related behaviors remains unclear. The present study evaluated the empirical validity of four contrasting theoretical conceptions which posit that (1) goals and expectancy-value variables are independent predictors of achievement-related outcomes (2) goals predict expectancy-values, (3) goals mediate the relation between expectancies and task-values, and (4) goals partially mediate the relation between expectancy-values and achievement outcomes, in predicting course performance, career intentions and academic aspirations. Path models evaluating these conceptions were tested separately in mathematics and language arts domains among 697 6th and 8th grade students. Results supported the fourth theoretical approach suggesting that expectancy-value variables predict achievement-related outcomes both directly and indirectly through achievement goals. These findings provide insight about the relation between expectancy-value and achievement goal theories and highlight their complementary role in predicting achievement behaviors.  相似文献   
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Abstract

The exact solution of the q-state Potts bridge model with competing ferromagnetic and antiferromagnetic interactions is obtained and corresponding regular and critical behaviour studied.  相似文献   
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The aim of this study was to examine the factorial and diagnostic validity of the Beck Depression Inventory-Second Edition (BDI-II) in Croatian primary health care. Data were collected using a medical outpatient sample (N = 314). Reliability measured by internal consistency proved to be high. While the Velicer MAP Test showed that extraction of only one factor is satisfactory, confirmatory factor analysis indicated the best fit for a 3-factor structure model consisting of cognitive, affective and somatic dimensions. Receiver operating characteristics (ROC) analysis demonstrated the BDI-II to have a satisfactory diagnostic validity in differentiating between healthy and depressed individuals in this setting. The area under the curve (AUC), sensitivity and specificity were high with an optimal cut-off score of 15/16. The implications of these findings are discussed regarding the use of the BDI-II as a screening instrument in primary health care settings.  相似文献   
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