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It was the main goal of this study to investigate the motor and visual-spatial development in primary school-aged children in Cameroon and Germany. Thirty-four children from each country completed a motor test and a mental rotation test. It was found that children in Cameroon showed a better motor ability (better overall gross motor score and also on most single items) than children in Germany did. This can be explained by the early motor stimulation in infancy in Cameroon. Concerning mental rotation performance, Cameroonian children perform below chance level. A positive correlation between the overall motor ability and mental rotation performance could only be analyzed and conducted in the German sample. Therefore, this study emphasizes the need for the development of culture-fair cognitive tests.  相似文献   
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HIV infection has evolved from a fatal to a treatable condition, leading to an increase in the rate of elderly People Living with HIV (PLWH). However, little is known about the psychosocial burden of elderly PLWH. Thus, the aim of this longitudinal multi-center cohort study was to investigate whether elderly PLWH experience more anxiety and depression and reduced health related quality of life (HRQOL) compared to elderly patients with other chronic conditions. PLWH were compared to diabetes patients (DM) and patients with minor health conditions (MHC), e.g. patients with hypertension or allergic conditions. All patients were over 50 years old. Anxiety and depression (HADS) as well as HRQOL (SF-36) were assessed at baseline and after 12 months. 218 PLWH, 249 DM and 254 MHC were included. At baseline, the study groups did not differ in anxiety, depression, and physical HRQOL. However, PLWH indicated lower mental HRQOL than DM and MHC patients (p = 0.001). We did not obtain any moderating effects showing a differential effect of patient characteristics on anxiety, depression, and HRQOL in the three patient groups. At follow-up, the level of anxiety, depression, and HRQOL did not change significantly. The prevalence of anxiety ranged between 27 and 35%, and that of depression between 17 and 28%. Thus, the results of our investigation tentatively suggest that the psychosocial adaptation to HIV among elderly PLWH resembles those of other chronic diseases. There may be some subtle impairments, though, as PLWH experienced lower mental HRQOL.  相似文献   
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One model of signal evolution is based on the notion that behaviours become increasingly detached from their original biological functions to obtain a communicative value. Selection may not always favour the evolution of such transitions, for instance, if signalling is costly due to predators usurping signal production. Here, we collected inertial movement sensing data recorded from multiple locations in free-ranging horses (Equus caballus), which we subjected to a machine learning algorithm to extract kinematic gestalt profiles. This yielded surprisingly rich and multi-layered sets of information. In particular, we were able to discriminate identity, breed, sex and some personality traits from the overall movement patterns of freely moving subjects. Our study suggests that, by attending to movement gestalts, domestic horses, and probably many other group-living animals, have access to rich social information passively but reliably made available by conspecifics, a finding that we discuss in relation with current signal evolution theories.  相似文献   
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There is ongoing debate about the extent to which nonhuman animals, like humans, can go beyond first-order perceptual information to abstract structural information from their environment. To provide more empirical evidence regarding this question, we examined what type of information great apes (chimpanzees, bonobos, and orangutans) gain from optical effects such as shadows and mirror images. In an initial experiment, we investigated whether apes would use mirror images and shadows to locate hidden food. We found that all examined ape species used these cues to find the food. Follow-up experiments showed that apes neither confused these optical effects with the food rewards nor did they merely associate cues with food. First, naïve chimpanzees used the shadow of the hidden food to locate it but they did not learn within the same number of trials to use a perceptually similar rubber patch as indicator of the hidden food reward. Second, apes made use of the mirror images to estimate the distance of the hidden food from their own body. Depending on the distance, apes either pointed into the direction of the food or tried to access the hidden food directly. Third, apes showed some sensitivity to the geometrical relation between mirror orientation and mirrored objects when searching hidden food. Fourth, apes tended to interpret mirror images and pictures of these mirror images differently depending on their prior knowledge. Together, these findings suggest that apes are sensitive to the optical relation between mirror images and shadows and their physical referents.  相似文献   
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Merdes  Christoph 《Synthese》2021,198(1):117-138

Science is a social epistemic enterprise. The complexity of research requires the division of cognitive labor. As a consequence, scientists have to present results and incorporate the results of others into their body of knowledge. This creates the possibility of strategic behavior, leading to phenomena such as publication bias. To analyze the dynamics of strategic behavior in epistemic communities, agent-based modeling suggests itself as a method. The phenomena generated by the developed agent-based simulation model reveal a diverse set of possible dynamics in strategically heterogeneous groups and support the claim that there is a trade-off between a behavioral rule’s efficacy to generate accurate beliefs under optimal conditions and its robustness to variation in the composition of the epistemic environment.

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The introduction summarizes the main arguments formulated in the six papers of this special issue on Constitutivism and Kantian Constructivism in Ethical Theory. We highlight the unifying theme addressed in the essays, i.e., the question of whether constitutivism is able to fulfill the promise of providing an account of normativity starting from relatively slender assumptions, including the avoidance of realist presuppositions.  相似文献   
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Daylight savings time represents a public good with costs and benefits. We provide the first comprehensive examination of the welfare effects of the spring and autumn transitions for the UK and Germany. Using individual-level data and a regression discontinuity design, we estimate the effect of the transitions on life satisfaction. Our results show that individuals in both the UK and Germany experience deteriorations in life satisfaction in the first week after the spring transition. We find no effect of the autumn transition. We attribute the negative effect of the spring transition to the reduction in the time endowment and the process of adjusting to the disruption in circadian rhythms. The effects are particularly strong for individuals with young children in the household. We conclude that the higher the shadow price of time, the more difficult is adjustment. Presumably, an increase in flexibility to reallocate time could reduce the welfare loss for individuals with binding time constraints.  相似文献   
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