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41.
This study addressed the development of language-mediated categorization longitudinally, on a sample of Serbian-speaking children aged 16–20 months. Twenty four children were tested 3 consecutive times on: categorization of unknown objects with a shared label and a similar shape; and categorization of unknown objects with a shared label, but no visual similarity. The task was embedded in a game-like activity which included real object manipulation, categorization of novel objects labeled with made-up names, and socio-pragmatic cues provided by the experimenter. Our results indicate that an average child develops the ability to categorize novel objects with a similar shape and a shared label around 16 months of age, whereas for novel objects with a shared label, but no visual similarity, this ability is acquired sometime between 18 and 20 months of age. Our results partly confirm research findings obtained in other languages, thus emphasizing the need for cross-linguistic and cross-cultural validation of all language-related developmental studies.  相似文献   
42.
The purpose of this study was to examine the effect of locus of control on university students' mental health and to examine possible mediational roles of self-esteem and coping. A total of 418 university students completed Rotters I-E Scale, Self-liking/self-competence Scale, Endlers Coping with Stressful Situations Scale and Depression, Anxiety and Stress Scale. The results showed that external locus of control, lower self-liking and self-competence, as well as less problem-focused and more emotion-focused coping predict more symptoms of depression, anxiety, and stress in university students. However, mediational analysis revealed that the effect of locus of control was fully mediated by self-esteem and coping, with self-liking and emotion-focused coping being the strongest mediators. Results suggest that beliefs about control affect beliefs about one's self-worth and coping strategies, which in turn can affect one's mental health.  相似文献   
43.
This paper studies the relationship between Argumentation Logic (AL), a recently defined logic based on the study of argumentation in AI, and classical Propositional Logic (PL). In particular, it shows that AL and PL are logically equivalent in that they have the same entailment relation from any given classically consistent theory. This equivalence follows from a correspondence between the non-acceptability of (arguments for) sentences in AL and Natural Deduction (ND) proofs of the complement of these sentences. The proof of this equivalence uses a restricted form of ND proofs, where hypotheses in the application of the Reductio of Absurdum inference rule are required to be “relevant” to the absurdity derived in the rule. The paper also discusses how the argumentative re-interpretation of PL could help control the application of ex-falso quodlibet in the presence of inconsistencies.  相似文献   
44.
Unavailability of published data and studies focused on young researchers in Europe and research integrity issues reveals that clear understanding and stance on this subject within European area is lacking. Our study provides information on attitudes and experiences of European researchers at early career stages (doctoral and postdoctoral level), based on a limited sample of respondents (n = 27). The study provides both quantitative and qualitative results for the examined issues. The data suggest that awareness and interest of the younger researchers surveyed in research integrity issues is high, however, it is often based on self-initiatives, with many of the respondents not having adequate training or any possibility to obtain it. Our attitude survey conducted within the European Council of Doctoral Candidates and Junior Researchers indicates that only 22 % of respondents had an opportunity to obtain relevant training (significantly less than in a study conducted in the U.S.), and that only one third believed that institutions and supervisors regularly paid attention to it. Further, we noted certain differences between disciplines. The study also reveals that many younger researchers felt they faced problems due to the misconduct of their senior colleagues and the existing institutional culture. The results of the study indicate a need for better prevention mechanisms, training and raising awareness activities. Preferably, junior researchers should be given an active role in shaping the integrity culture. It should be noted that the presented results should be considered in the context of the limitations stemming from the small-scale survey. This paper encourages further research activities on research integrity practices to provide stronger evidence on the attitudes and experiences of young researchers in Europe and other parts of the world.  相似文献   
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46.
Lacking in the research on work and well-being is a focus on the characteristics of the employment role that contribute to well-being and their differential relations across ethnicity and gender. White and Black women and men at midlife (ages 40-64) were studied. The samples were drawn from two national surveys and included 186 White women, 202 White men, 254 Black women, and 169 Black men. Multiple regression analyses were conducted to assess the relation of work commitment, job satisfaction, role stress, occupational status and personal income to perceived control, life satisfaction, and happiness. Marital status, age, and hours worked were included as control variables. Results indicate that job satisfaction is positively related to life satisfaction for all four groups, and to happiness for White women and Black men. Personal income is positively related to perceived control for Black women and White men, and to life satisfaction for White women. Occupational status is positively related to perceived control for White and Black women; role stress is negatively related to life satisfaction among White men, and to happiness among Black women. Among the control variable, being married positively related to well-being for all four race-sex groups.  相似文献   
47.
There is often something wrong with merely promising to try to φ. In this article I explain what is wrong with such promises. I argue that a promise to try to φ, when it is entirely up to us to φ, is always wrong because it hides a possible choice under the veil of our susceptibility to circumstances beyond our control. I furthermore argue that this is often also the case when matters are not entirely up to us. Finally, I contend that sometimes the promise to try places undue burdens on the promisee.  相似文献   
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49.
In 3 studies, the authors investigated the functional role of psychological resilience and positive emotions in the stress process. Studies 1a and 1b explored naturally occurring daily stressors. Study 2 examined data from a sample of recently bereaved widows. Across studies, multilevel random coefficient modeling analyses revealed that the occurrence of daily positive emotions serves to moderate stress reactivity and mediate stress recovery. Findings also indicated that differences in psychological resilience accounted for meaningful variation in daily emotional responses to stress. Higher levels of trait resilience predicted a weaker association between positive and negative emotions, particularly on days characterized by heightened stress. Finally, findings indicated that over time, the experience of positive emotions functions to assist high-resilient individuals in their ability to recover effectively from daily stress. Implications for research into protective factors that serve to inhibit the scope, severity, and diffusion of daily stressors in later adulthood are discussed.  相似文献   
50.
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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