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51.
Learners studying mechanical or technical processes via dynamic visualizations often fail to build an accurate mental representation
of the system’s movements. Based on embodied theories of cognition assuming that action, perception, and cognition are closely
intertwined, this paper proposes that the learning effectiveness of dynamic visualizations could be enhanced by grounding
the movements of the presentation in people’s own bodily experiences during learning. We discuss recent research on embodied
cognition and provide specific strategies for how the body can be used to ground movements during the learning process: (1)
making or observing gestures, (2) manipulating and interacting with objects, (3) using body metaphors, and (4) using eye movements
as retrieval cues. Implications for the design of dynamic visualizations as well as directions for future research are presented. 相似文献
52.
Karel Kreijns Paul A. Kirschner Wim Jochems Hans van Buuren 《Education and Information Technologies》2011,16(4):365-381
Social presence—the degree to which ‘the other’ in a communication appears to be a ‘real’ person—has captured the attention
of those dealing with learning in groups through computer-supported collaborative learning environments. The concept is important
because it affects participation and social interaction, both necessary for effective collaboration and knowledge construction.
This article reports on the construction and validation of a self-reporting (Dutch-language) Social Presence Scale to determine
perceived social presence in distributed learning groups using computer-supported collaborative learning environments. The
result is a one-dimensional scale consisting of five items with an internal consistency of .81. We used a nomological network
of similar constructs for further validation. The findings suggest that the Social Presence Scale has potential to be useful
as a measure for social presence. 相似文献
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55.
Formal models for service composition have been proposed with the variation of the requirements of service developers. Some
famous models have provided checking and verification techniques and tools for the behavior of service composition. These
models generally focus much on the message flow of web services and neglecting the data contained in the exchanged messages
among services, which restrict the application range of these models and also the web service techniques. As new kind of services
with different protocols and communication methods have appeared, it is needed to model service composition from a new view
which is adapted to the new development in service area. In this paper we offer a function oriented model of service composition
which treats the composite service as a software system and specify the function of services which can be directly used to
the realization by service providers. 相似文献
56.
The author articulates key stressors in the lives of families who are homeless. These stresses often combine with barriers such as lack of job opportunities and/or insensitive professionals. Strategies for helping homeless families overcome these barriers and related issues are presented. 相似文献
57.
Principal Recruitment: An Empirical Evaluation of a School District’s Internal Pool of Principal Certified Personnel 总被引:1,自引:0,他引:1
Paul A. Winter James S. Rinehart Marco A. Muñoz 《Journal of Personnel Evaluation in Education》2002,16(2):129-141
Applicant pools for principal vacancies are shrinking nationwide. This shortage of job applicants requires school districts to evaluate their internal pools of principal certified personnel. In this study, 194 certified individuals from a large school district responded to a survey measuring attraction to the job of principal, current job satisfaction versus expected satisfaction in the job of principal, barriers to pursuing the job, and recommended changes in the job. Few participants intended to apply for principal vacancies due to age (median=51), lack of self-reported capability to do the job, and satisfaction with the current job. Participants perceived their job satisfaction would decrease on assuming the job of principal relative to factors such as time with family and job security, and increase relative to factors such as salary and opportunity to experience varied activities. Implications for principal recruitment and recommendations for restructuring the job are discussed. 相似文献
58.
The rationale was to apply Piaget’s theory and methods to the study of the phylogenetic development of cognitive abilities. It was asked whether squirrel monkeys have the prerequisite skills for conservation of quantity, and, specifically, whether they might respond differentially to equivalent and unequivalent volumetric cues. All monkeys responded significantly and differentially to pairs of identical objects or pairs of objects similar only in volume vs. pairs of objects which differed in volume. It was concluded that squirrel monkeys have the prerequisite skills for the conservation of quantity. Discussion included methodological problems associated with demonstrating conservation in nonhumans as well as the potential usefulness of Piaget’s theory for phylogenetic studies of intelligence. 相似文献
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Yangxueqingnao particles inhibit rat vascular smooth muscle cell proliferation induced by lysophosphatidic acid 总被引:1,自引:0,他引:1
Cai W Xu Y Chen JZ Huang SR Lu ZY Wang ZK 《Journal of Zhejiang University. Science. B》2005,6(9):892-896
Objective: To observe the effect of Yangxueqingnao particles on rat vascular smooth muscle cell (VSMC) proliferation induced by lysophosphatidic acid (LPA). Methods: The amount of3H-TdR (3H-thymidine) admixed in cultured rat VSMC was measured and mitogen-activated protein kinase (MAPK) activity and lipid peroxidation end product malondialdehyde (MDA)content of the VSMC were assayed. Results: 1×10-9, 1×10-8, 1×10-7 mol/L LPA in a concentration dependent manner, induced the amount of 3H-TdR admixed, MAP kinase activity, and MDA content of the cultured rat VSMC to increase. However, 5%, 10%,and 15% Yangxueqingnao serum preincubation resulted in a decrease of 23.0%, 42.0%, and 52.0% (P<0.01) respectively in the amount of 3H-TdR admixed, a decline in VSMC MAP kinase activity of 13.9% (P<0.05), 29.6% (P<0.01), and 48.9% (P<0.01)respectively, and also, a decrease in MDA content of VSMC of 19.4%, 24.7%, and 43.2% (P<0.01) respectively, in the 1×10-7mol/L LPA-treated VSMC. Conclusions: LPA activates the proliferation and lipid peroxidation of VSMC in a concentration dependent manner. The LPA-induced VSMC proliferation is related to the activity of MAP kinases, enzymes involved in an intracellular signalling pathway. The results of the present study showed that Yangxueqingnao particles can effectively inhibit LPA-induced VSMC proliferation, MAP kinase activation, and reduce lipid peroxidative lesion. 相似文献