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181.
Vocal learning is a rare skill in mammals, and we have limited information about the contexts in which they use it. Previous studies suggested that cetaceans in general are skilled at imitating sounds, but only few species have been studied to date. To expand this investigation to another species and to investigate the possible influence of the social environment on vocal learning, we studied the whistle repertoire of a female Risso’s dolphin (Grampus griseus) that was stranded at an early age and was subsequently raised in a group of bottlenose dolphins (Tursiops truncatus). We show that this cross-fostered animal produced vocal signals more akin to those of its Tursiops poolmates than those of Risso’s dolphins in the wild. This is one of very few systematic cross-fostering studies in cetaceans and the first to suggest vocal production learning in the Risso’s dolphin. Our findings also suggest that social experience is a major factor in the development of the vocal repertoire in this species.  相似文献   
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This paper studies the economic effect of immigration on native working conditions, focusing on the impact of the inflow of immigrant labour on occupational mobility among native workers. Basing on a gender-segmented labour market, we propose an extension of the model presented by Peri and Sparber American Economic Journal: Applied Economics, 1(3), 135-169, (2009). The model controls for gender and time in order to check for potential differences in immigration effects associated with gender or immigrant length of residence. This research reveals the existence of such differences, by showing that female immigrant inflow has a greater positive short-term impact on occupational mobility among female unskilled native workers. In addition, the long-term study discloses a slight occupational assimilation of male immigrants towards employment patterns of male native workers and a permanent confinement of female immigrants in a few “niche jobs”.  相似文献   
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Early math skills are determined by higher cognitive processes that are particularly important for acquiring and developing skills during a child's early education. Such processes could be a critical target for identifying students at risk for math learning difficulties. Few studies have considered the use of a structural equation method to rationalize these relations. Participating in this study were 207 preschool students ages 59 to 72 months, 108 boys and 99 girls. Performance with respect to early math skills, early literacy, general intelligence, working memory, and short‐term memory was assessed. A structural equation model explaining 64.3% of the variance in early math skills was applied. Early literacy exhibited the highest statistical significance (β = 0.443, < 0.05), followed by intelligence (β = 0.286, < 0.05), working memory (β = 0.220, < 0.05), and short‐term memory (β = 0.213, < 0.05). Correlations between the independent variables were also significant (< 0.05). According to the results, cognitive variables should be included in remedial intervention programs.  相似文献   
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According to Maslow’s (Psychol Rev 50:370–396, 1943) hierarchical theory of needs, people do not become sensitized to “higher” level needs until they have satisfied their “lower” level needs (a moderator hypothesis); until then, they are unprepared to benefit from higher-level satisfactions. But according to the self-determination theory (SDT) model, high-level psychological needs, when met, are non-contingently beneficial (a main effect-only hypothesis). In two large-N studies of Russian energy companies, we measured low-level need-satisfaction in terms of felt security and felt financial satisfaction, and measured high-level need satisfaction in terms of SDT’s basic needs of autonomy, competence, and relatedness. In both studies, both the lower level and higher level need-satisfaction sets had strong main effects upon many positive work outcomes, including intrinsic motivation, organizational commitment, and SWB. In Study 2, Maslow’s “prepared to benefit” hypothesis was supported, in that satisfaction of high-level needs had slightly larger effects on outcomes when combined with satisfaction of low-level needs. However this was not found in Study 1. Potentials for integrating the SDT and Maslow need theories are discussed.  相似文献   
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In our contemporary age, where a combination of individualism and mutual distrust is unhappily common among people and society is “liquid” and disoriented, so-called intermediate units (groups, associations) are a precious resource that promotes positive coexistence within organizations and in local communities, too. The present contribution describes an example of such an intermediate unit, the Talent Club, located in a peripheral neighborhood of a metropolitan area in northern Italy. This case study shows the development of positive living and working together in organizations and their transformation in the tool for community development and good coexistence. Qualitative and quantitative data show that the relational aspect is crucial because it promotes authentic exchange among people, supporting participation and social cohesion against self-referential habits and isolation. Although at present the Talent Club is mostly functioning in a affiliating coexistence among members, seeds of a more generative coexistence are clearly detectable.  相似文献   
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The article deals with Aristotle’s conception of ‘place’, which is of cruсial importance for his theory of motion. It is shown that in the physics of Aristotle there is no concept of spасe; instead, there is the notion of ‘place’ of a body (topos). Aristotle considered ‘place’ as the first boundary of a body embracing (containing) the body in question. The author shows the incommensurability between the spatial ideas of the Stagirite and the similar ideas of Newtonian physics. The article states that in order to give an adequate reconstruction of Aristotle’s concept of ‘place’ we need to take into account two different levels of consideration: local and global. Places locally separable (from bodies) cannot be separated on the global level. In Newtonian physics, bodies are separable from places on both levels. The nature of parallelism of ideas between Aristotle’s conception of ‘place’ and the notions of space in present-day physics is analysed.  相似文献   
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