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91.
The aim of this study was to investigate the muscle coordination underlying pedaling in untrained subjects by using the muscle synergies paradigm, and to connect it with the inter-individual variability of EMG patterns and applied forces. Nine subjects performed a pedaling exercise on a cycle-simulator. Applied forces were recorded by means of instrumented pedals able to measure two force components. EMG signals were recorded from eight muscles of the dominant leg, and Nonnegative Matrix Factorization was applied to extract muscle synergy vectors W and time-varying activation coefficients H. Inter-individual variability was assessed for EMG patterns, force profiles, and H. Four modules were sufficient to reconstruct the muscle activation repertoire for all the subjects (variance accounted for >90% for each muscle). These modules were found to be highly similar between subjects in terms of W (mean r = .89), while most of the variability in force profiles and EMG patterns was reflected, in the muscle synergy structure, in the variability of H. These four modules have a functional interpretation when related to force distribution along the pedaling cycle, and the structure of W is shared with that present in human walking, suggesting the existence of a modular motor control in humans.  相似文献   
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93.
Two experiments examined the interaction of vision and articular proprioception in simple one-hand catching. In Experiment 1 (N = 18) skilled baseball and Softball players used the left and right hands to catch slowly moving tennis balls, while Experiment 2(N = 16) used novice catchers as subjects. In half the trials, sight of the catching hand was prevented by placing a screen alongside the subjects’ face. Results of Experiment 1 revealed that the screen caused minimal disruption of the positioning phase of the catch, with moderate disruption of the grasping phase. However, for the unskilled subjects of Experiment 2, the screen caused considerable disruption of positioning. The data provide only minimal support for Smyth and Marriott’s (1982) contention that limb position is inadequately specified by articular proprioception. It is argued that skill level serves as a mediator in the ability to use proprioception for limb positioning, but vision appears necessary to control the precise temporal organization of the grasp phase of one-hand catching.  相似文献   
94.
The purpose of our study was to further elucidate how employees should behave at work to increase their chances of being mentored by their immediate supervisor. To that end, we experimentally tested how three domains of employee performance [task performance (TP), organizational citizenship behavior (OCB) targeting the supervisor, and counterproductive work behavior (CWB) targeting coworkers] affect supervisors’ willingness to mentor. Each performance domain affected willingness to mentor. OCB had the weakest of the three main effects. Finally, the positive effect of TP was stronger when employees displayed less CWB.  相似文献   
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96.
Nanoscale science, research, and technology present a complex set of circumstances. First of all, this field involves many different subjects, including biology, chemistry, physics, and environment sciences. Secondly, although scientists are working increasingly at a molecular level, nanotechnology is about much more than a reduction of scale. Indeed, nanoscience and Nanotechnologies offer an unprecedented ability to control and manipulate nature, offering hope for progress. Ethical perspectives vary considerably in this field, but commentators and researchers share a concern about a specific worrisome issue: the lack of appropriate ethical and legal principles and processes (associated with issues including health risks, human body manipulation, and private life violation), to guide nanotechnological R&D, commercialization, and final use. Some authors partially reject this concern by suggesting that Nanoscience and Nanotechnologies do not constitute an autonomous category, and that they are instead just the operative result of combining other traditional areas of study. However the nanotechnological debate brings up the semantic and content issues of bioethics and foments a contentious discussion emphasizing human dignity. Issues include enhancement versus therapeutic intervention, traceability versus privacy, and societal benefits versus risks. From these preliminary considerations, we will move on to discuss (I) the traditional, although still controversial, relationship between bioethics and human dignity, and (II) return to the subject of nanotechnology. We will discuss how today in Europe, although still indefinite, the principle of respect for human dignity is a welcomed contributor to "ethical vigilance" about the uncertain development of new nano-scale technologies. We will also note how U.S. strategy in this regard is simply lacking and appears only as a purely discursive "key issue in long term ".  相似文献   
97.
There is evidence that 4.5-month-olds do not always use surface pattern to individuate objects but that they can be primed to attend to pattern differences through select experiences. For example, if infants are first shown events in which the pattern of an object predicts its function (dotted containers pound and striped containers pour), they will attend to pattern differences in a subsequent individuation task. However, 4.5-month-olds must see multiple exemplars of the pound and pour events and view the dotted and striped containers together during the events. These results suggest that it is the formation of event categories, in which pattern is linked to object function, that supports pattern priming and that direct comparison of the exemplars facilitates the extraction of event categories. The present research investigated conditions that support the comparison process in 4.5-month-olds. The results revealed that the comparison process was initiated only when the dotted and striped containers were seen directly adjacent to each other; if the containers sat far apart, so that infants had to shift their gaze to compare them, event categories were not extracted. In addition, it was comparison of the two patterned containers, and not comparison of the two function events, that was critical to the formation of event categories. These results join a growing body of research indicating the importance of comparison to category formation in infants and reveal the impact of categorization and comparison processes on object individuation in infancy.  相似文献   
98.
What are creative people like? Openness to experience is important to creativity, but little is known about plasticity, the higher-order factor that subsumes openness. College students (n = 189) completed measures of the Big Five and measures of creative cognition (fluency and quality of divergent thinking), everyday creative behaviors, creative achievement, and self-rated creativity. Latent variable models found broad effects of openness to experience and few effects of the other four domains. At the higher-order level, plasticity predicted higher scores on nearly all of the facets of creativity, and stability had several significant effects. For some creativity measures, plasticity and stability had opposing effects. Tests of latent interactions found no significant effects: plasticity and stability predict creatively independently, not jointly.  相似文献   
99.
Wilcox T  Chapa C 《Cognition》2002,84(1):B1-10
Two experiments document that conceptual knowledge influences 3-year-olds' extension of novel words. In Experiment 1, when objects were described as having conceptual properties typical of artifacts, children extended novel labels for these objects on the basis of shape alone. When the very same objects were described as having conceptual properties typical of animate kinds, children extended novel labels for these objects on the basis of both shape and texture. Moreover, providing a salient perceptual cue (Experiment 2) did not interfere with children's reliance on conceptual information in extending novel words: when an object with eyes was labeled with a novel word in the context of a story describing the object as an artifact, children extended the label on the basis of shape alone (i.e. as though the object were an artifact). These results, which challenge directly the position that 'dumb attentional mechanisms' can account for word learning, stand as evidence for the central role of conceptual information in mapping words to meaning.  相似文献   
100.
The influence of adaptive and maladaptive perfectionism on creativity was examined. Initially, six measures of creativity were administered, including creative self-perceptions, behavior, and performance measures. Adaptive perfectionism was weakly positively related to creativity, whereas maladaptive perfectionism was unrelated to creativity across five of the six measures. A follow-up study assessed whether initial findings could be generalized to an everyday problem-solving task. Results indicated that adaptive perfectionism was related to higher quality but not originality of solutions. Further, a curvilinear relationship in the shape of an inverted “U” occurred between adaptive perfectionism and four of eight creativity measures. Overall, adaptive perfectionism was consistently, albeit weakly, related to creativity across various types of measures, whereas maladaptive perfectionism was not related to creativity.  相似文献   
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