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41.
A substantial amount of research shows that social exclusion is a threat to mental health. In the research reported here, we tested the hypothesis that the presence of a companion animal can serve as a buffer against these adverse effects. In a controlled laboratory experiment, we found that only socially excluded participants who did not work in the presence of a dog reported lower mental well-being compared with socially excluded participants who performed in the presence of a dog and participants who were not socially excluded. The theoretical and practical implications of these findings are discussed.  相似文献   
42.
Rahman  Shahid  Rückert  Helge 《Synthese》2001,127(1-2):105-139
Synthese - Many of the discussions about conditionals can best be put as follows:can those conditionals that involve an entailment relation be formulatedwithin a formal system? The reasons for the...  相似文献   
43.
Müller  Thomas  Placek  Tomasz 《Synthese》2001,128(3):343-379
Since the validity of Bell's inequalities implies the existence of joint probabilities for non-commuting observables, there is no universal consensus as to what the violation of these inequalities signifies. While the majority view is that the violation teaches us an important lesson about the possibility of explanations, if not about metaphysical issues, there is also a minimalist position claiming that the violation is to be expected from simple facts about probability theory. This minimalist position is backed by theorems due to A. Fine and I. Pitowsky.Our paper shows that the minimalist position cannot be sustained. To this end,we give a formally rigorous interpretation of joint probabilities in thecombined modal and spatiotemporal framework of `stochastic outcomes inbranching space-time' (SOBST) (Kowalski and Placek, 1999; Placek, 2000). We show in this framework that the claim that there can be no joint probabilities fornon-commuting observables is incorrect. The lesson from Fine's theorem is notthat Bell's inequalities will be violated anyhow, but that an adequate modelfor the Bell/Aspect experiment must not define global joint probabilities. Thus we investigate the class of stochastic hidden variable models, whichprima facie do not define such joint probabilities. The reasonwhy these models fail supports the majority view: Bell's inequalities are notjust a mathematical artifact.  相似文献   
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Previous research has shown that a considerable number of primates can remember the location and fruiting state of individual trees in their home range. This enables them to relocate fruit or predict whether previously encountered fruit has ripened. Recent studies, however, suggest that the ability of primates to cognitively map fruit-bearing trees is limited. In this study, we investigated an alternative and arguably simpler, more efficient strategy, the use of synchrony, a botanical characteristic of a large number of fruit species. Synchronous fruiting would allow the prediction of the fruiting state of a large number of trees without having to first check the trees. We studied whether rainforest primates, grey-cheeked mangabeys in the Kibale National Park, Uganda, used synchrony in fruit emergence to find fruit. We analysed the movements of adult males towards Uvariopsis congensis food trees, a strongly synchronous fruiting species with different local patterns of synchrony. Monkeys approached within crown distance, entered and inspected significantly more Uvariopsis trees when the percentage of trees with ripe fruit was high compared to when it was low. Since the effect was also found for empty trees, the monkeys likely followed a synchrony-based inspection strategy. We found no indication that the monkeys generalised this strategy to all Uvariopsis trees within their home range. Instead, they attended to fruiting peaks in local areas within the home range and adjusted their inspective behaviour accordingly revealing that non-human primates use botanical knowledge in a flexible way.  相似文献   
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47.
Transformations of hand movements by tools such as levers or electronic input devices can invoke performance costs compared to untransformed movements. This study investigated by means of the Psychological Refractory Period (PRP) paradigm at which stage of information processing such tool-transformation costs arise. We used an inversion transformation, that is, the movement of the operating hand was transformed into a spatially incompatible movement of a lever. As a basic tool-transformation effect, the initiation of inverted tool movements was delayed compared to noninverted movements. Experiment 1 suggested a central (or postcentral) locus of this tool-transformation effect and ruled out a (precentral) perceptual locus. Experiments 2 and 3 confirmed the central locus and ruled out a later, motor-related stage of processing. The results show that spatially incompatible tool movements delay a capacity-limited stage of information processing, often referred to as response selection.  相似文献   
48.
The study examines whether self-efficacy mediates between intention and behavior, and whether appearance norms and self-efficacy are additive or synergistic predictors of sunscreen use. At two measurement points in time, 14 weeks apart, 154 individuals responded to an online questionnaire. Moderated mediation was tested by hierarchical regression analyses. Self-efficacy mediated the intention-behavior relationship, whereas appearance norms emerged as a moderator of the self-efficacy-sunscreen use relationship. The model accounted for 22% of the behavior variance at time 2. For individuals who believe that they would look more attractive with a tan, self-efficacy did not have a strong effect on behavior. Thus, for skin-protection motivation to become effective, self-efficacy is needed in conjunction with less positive appearance norms. Implications for public health promotion and mass media sunscreen use campaigns are discussed.  相似文献   
49.
This longitudinal study examined the concurrent and predictive relations between executive function (EF) and theory of mind (ToM) in 82 preschoolers who were assessed when they were 2, 3, and 4 years old. The results showed that the concurrent relation between EF and ToM, after controlling for age, verbal ability, and sex, was significant at 3 and 4 years of age but not at 2 years of age. Hierarchical regression analyses showed that EF at age 2 significantly predicted ToM at age 3 and that EF at age 3 significantly predicted ToM at age 4, over and above the effects of age, verbal ability, and prior performance on ToM tasks. However, ToM at ages 2 and 3 did not explain a significant amount of variance in EF at age 4. Bootstrap procedures revealed that verbal ability at age 3 fully mediated the relation between ToM at age 2 and EF at age 4.  相似文献   
50.
Military experience is an important turning point in a person's life and, consequently, is associated with important life outcomes. Using a large longitudinal sample of German males, we examined whether personality traits played a role during this period. Results indicated that personality traits prospectively predicted the decision to enter the military. People lower in agreeableness, neuroticism, and openness to experience during high school were more likely to enter the military after graduation. In addition, military training was associated with changes in personality. Compared with a control group, military recruits had lower levels of agreeableness after training. These levels persisted 5 years after training, even after participants entered college or the labor market. This study is one of the first to identify life experiences associated with changes in personality traits. Moreover, our results suggest that military experiences may have a long-lasting influence on individual-level characteristics.  相似文献   
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