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231.
We investigated age-related differences in finger coordination during rotational hand actions. Two hypotheses based on earlier studies were tested: higher safety margins and lower synergy indices were expected in the elderly. Young and elderly subjects held a handle instrumented with five six-component force sensors and performed discrete accurate pronation and supination movements. The weight of the system was counterbalanced with another load. Indices of synergies stabilizing salient performance variables, such as total normal force, total tangential force, moments produced by these forces, and total moment of force were computed at two levels of a hypothetical control hierarchy, at the virtual finger-thumb level and at the individual finger level. At each level, synergy indices reflected the normalized difference between the sum of the variances of elemental variables and variance of their combined output, both computed at comparable phases over repetitive trials. The elderly group performed the task slower and showed lower safety margins for the thumb during the rotation phase. Overall, the synergy indices were not lower in the elderly group. In several cases, these indices were significantly higher in the elderly than in the younger participants. Hence, both main hypotheses have been falsified. We interpret the unexpectedly low safety margins in the elderly as resulting from several factors such as increased force variability, impaired feed-forward control, and the fact that there was no danger of dropping the object. Our results suggest that in some natural tasks, such as the one used in this study, healthy elderly persons show no impairment, as compared to younger persons, in their ability to organize digits into synergies stabilizing salient performance variables. 相似文献
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Kim Yin Chan Moon-ho R. Ho Oleksandr S. Chernyshenko Olwen Bedford Marilyn A. Uy David Gomulya Y.L. Sam Wei Ming J. Phan 《Journal of Vocational Behavior》2012,81(1):73-88
We propose a person-centered framework for conceptualizing subjective careers in an increasingly boundaryless work context. Specifically, we argue that entrepreneurship, professionalism, and leadership (EPL) can serve as three key dimensions of subjective career space. We relate this framework to earlier macro-level national and organizational career models proposed by Kanter (1989) and Schein (1978). Our empirical study involving 10,326 Singaporean university students demonstrated that entrepreneurial, professional, and leadership career aspirations (including motivations, efficacies, and intentions) can be measured independently, that these career dimensions are independent of vocational interests, and that they are to some degree viewed as competing career alternatives. We also show that EPL motivation profiles can operationalize the boundaryless and protean career concepts. Individuals concurrently high in entrepreneurial, professional, and leadership career motivations, and those high in entrepreneurial and leadership motivations are highest in boundaryless and self-directed career attitudes, while those primarily motivated for professional careers hold the most traditional career attitudes. We conclude by discussing the potential of the framework for understanding human resource issues at organizational and national levels and for enhancing the study of entrepreneurship, professionalism, and leadership. 相似文献
234.
The purpose of this article is to present the current status of the literature related to stress in clinical psychology trainees (CPTs), and to offer research directions for investigating stress in this population and ways to enhance self‐care in these individuals. The following conclusions emerge from the review: (1) CPTs are vulnerable to elevated stress; (2) undue stress can negatively impact CPTs' personal and professional functioning and, in turn, result in less than optimal standards of care for clients; (3) there is a dearth of studies on stress in this population and no published intervention studies; (4) incorporating self‐care strategies into clinical psychology training is recommended; and (5) “third‐wave” cognitive behaviour therapy stress management interventions have been efficacious in comparable populations. In view of the potential costs of elevated stress to trainees themselves and their clients, research on stress and stress management in this population is of a high priority. Broad research agendas are proposed for these two domains. Modifications to clinical training programmes to reduce trainee stress are required and should be evidence‐based and systematically revaluated. 相似文献
235.
Bethany Rittle‐Johnson Jon R. Star Kelley Durkin 《The British journal of educational psychology》2012,82(3):436-455
Background. A key learning outcome in problem‐solving domains is the development of procedural flexibility, where learners know multiple procedures and use them appropriately to solve a range of problems (e.g., Verschaffel, Luwel, Torbeyns, & Van Dooren, 2009 ). However, students often fail to become flexible problem solvers in mathematics. To support flexibility, teaching standards in many countries recommend that students be exposed to multiple procedures early in instruction and be encouraged to compare them. Aims. We experimentally evaluated this recommended instructional practice for supporting procedural flexibility during a classroom lesson, relative to two alternative conditions. The alternatives reflected the common instructional practice of delayed exposure to multiple procedures, either with or without comparison of procedures. Sample. Grade 8 students from two public schools (N= 198) were randomly assigned to condition. Students had not received prior instruction on multi‐step equation solving, which was the topic of our lessons. Method. Students learned about multi‐step equation solving under one of three conditions in math class for about 3 hr. They also completed a pre‐test, post‐test, and 1‐month‐retention test on their procedural knowledge, procedural flexibility, and conceptual knowledge of equation solving. Results. Novices who compared procedures immediately were more flexible problem solvers than those who did not, even on a 1‐month retention test. Although condition had limited direct impact on conceptual and procedural knowledge, greater flexibility was associated with greater knowledge of both types. Conclusions. Comparing procedures can support flexibility in novices and early introduction to multiple procedures may be one important reason. 相似文献
236.
We extended the classic anorthoscopic viewing procedure to test a model of visualization of 3D structures from 2D cross-sections. Four experiments were conducted to examine key processes described in the model, localizing cross-sections within a common frame of reference and spatiotemporal integration of cross sections into a hierarchical object representation. Participants used a hand-held device to reveal a hidden object as a sequence of cross-sectional images. The process of localization was manipulated by contrasting two displays, in situ vs. ex situ, which differed in whether cross sections were presented at their source locations or displaced to a remote screen. The process of integration was manipulated by varying the structural complexity of target objects and their components. Experiments 1 and 2 demonstrated visualization of 2D and 3D line-segment objects and verified predictions about display and complexity effects. In Experiments 3 and 4, the visualized forms were familiar letters and numbers. Errors and orientation effects showed that displacing cross-sectional images to a remote display (ex situ viewing) impeded the ability to determine spatial relationships among pattern components, a failure of integration at the object level. 相似文献
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Jan‐Olav Henriksen 《Dialog》2012,51(2):114-124
Abstract : In this article I argue that the Lutheran doctrine of two kingdoms provides a good basis for the legitimate participation of all citizens in political discourse and decisions, no matter what faith they hold. The argument is backed by selected insights from philosopher Jürgen Habermas and sociologists Linda Woodhead and Paul Heelas. Against this backdrop, I suggest some challenges for a theology that addresses issues related to religion and society. 相似文献
239.
Kelly Denton‐Borhaug 《Dialog》2012,51(2):125-134
Abstract : This article digs beneath the surface of American assumptions regarding war to explore the ethical interconnections between national identity, war, and religion. Striking differences emerge between the dynamics of religion and politics with regard to war and peace in presidential speeches regarding the Iraq and Afghanistan wars, and the analysis of war from an earlier generation, encapsulated by Dr. Martin Luther King Jr.'s “Beyond Vietnam: A Call to Conscience,” from 1967. Study of this political discourse helps us better understand our own reality in the United States, and the moral consequences of our beliefs about war, sacrifice, the human character, and the identity of the nation. 相似文献
240.