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241.
Kenneth H. McCulloch 《Journal of Adventure Education & Outdoor Learning》2004,4(2):185-197
Case studies of the contemporary UK sail training movement are used to illustrate the competing expressions of purpose in this field. Two sail training organisations are described and a case study voyage under the aegis of each is presented. The differences between the approaches are analysed as “traditions” or ideologies, articulated through distinctive interpretations of power and contrasting approaches to participation in decision making. It is argued that choices regarding the type of vessel used and the voyages made are not neutral technical decisions but have ideological significance. In conclusion the application of such an analysis to other kinds of outdoor and adventure education is considered. 相似文献
242.
Objective: To determine the effective nucleotide sites of ribozymes against HCV, and obtain a highly effective, nontoxic and
inexpensive antisense ribozyme specific for HCV. Methods: Two effective ribozymes, targeted to HCV 5’NC region and C region,
were designed and synthesized. Eukaryotic expression vectors, pSV2-gpt. CD-SR (, containing either HCRZNC or HCRZC were constructued
and transfected into MT-2 cells, which had been infected by HCV. Quantitative PCR and hydridization were used to determine
the effect of inhibition of HCV by ribozymes. Results: HCRZNC and HCRZC suppressed the replication of HCV by 54.7% and 62.1%,
respectively. Furthermore, when both ribozymes were cotransfected into cells, they suppressed replication by 78.8%. Conclusion:
Two specific antisense ribozymes have strong inhibitory effects on the replication of HCV in cultured cells, and have better
effect when used together. 相似文献
243.
Daniel Ansari Roland H. Grabner Karl Koschutnig Gernot Reishofer Franz Ebner 《Learning and individual differences》2011,21(6):636-643
Data from both neuropsychological and neuroimaging studies have implicated the left inferior parietal cortex in calculation. Comparatively less attention has been paid to the neural responses associated with the commission of calculation errors and how the processing of arithmetic errors is modulated by individual differences in mathematical competence. Do more competent individuals exhibit a different brain response to errors than less mathematically able individuals? These outstanding questions were addressed in the present functional Magnetic Resonance Imaging (fMRI) study through an investigation of which brain regions respond more to erroneously versus correctly solved arithmetic problems while a group of 24 adult participants with varying levels of mathematical competence solved problems of all four arithmetic operations. Despite high levels of accuracy, a robust main effect of accuracy (incorrect vs. correct) was observed in both medial and lateral regions of the prefrontal cortex. These regions have frequently been associated with both the detection of errors and the deployment of cognitive control following an error. Furthermore, mathematical competence was found to modulate the activation of an area in the right dorsolateral prefrontal cortex. Specifically, individuals with relatively higher mathematical competence (n = 12) were found to activate this region more for incorrectly solved trials than their less mathematically competent peers (n = 12). Taken together, these findings suggest that the commission of arithmetic errors modulates responses of prefrontal regions and, moreover, that activation of the right lateral prefrontal cortex during arithmetic errors is affected by individual differences in mathematical competence. In view of the evidence associating the lateral prefrontal cortex with the implementation of cognitive control, we suggest that individuals with relatively high mathematical competence may exhibit greater awareness of calculation mistakes and implement greater control following the commission of errors. 相似文献
244.
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
245.
Silva KM Spinrad TL Eisenberg N Sulik MJ Valiente C Huerta S Edwards A Eggum ND Kupfer AS Lonigan CJ Phillips BM Wilson SB Clancy-Menchetti J Landry SH Swank PR Assel MA Taylor HB;School Readiness Consortium 《Early education and development》2011,22(3):434-460
RESEARCH FINDINGS: The purpose of this study was to examine the relations of children's effortful control and quality of relationships with teachers to school attitudes longitudinally in an ethnically diverse and economically disadvantaged sample. Data were collected as part of a larger intervention project during mid-fall, winter, and late spring (ns = 823, 722, and 758, respectively) for 2 cohorts of 3- to 5-year-olds (collected during 2 different school years). Children's effortful control was assessed in the fall with parents' and teachers' reports and 2 behavioral measures. Teacher-child relationship quality was assessed mid-year with teachers' reports of closeness and conflict. Attitudes toward school were assessed in late spring using teachers' and students' reports of school avoidance and liking. Effortful control, in general, was positively correlated with teacher-child closeness and school liking and negatively correlated with conflict and school avoidance. Using structural equation modeling and controlling for sex and ethnicity, we found that effortful control was positively related to teacher-child relationship quality, which in turn was positively related to school attitudes. Furthermore, the relation of effortful control to school attitudes was mediated by teacher-child relationship quality. PRACTICE OR POLICY: Results provide evidence for the importance of relational processes that take place within the classroom context and have implications for teachers and clinicians working to increase school success in ethnic minority and low-income children. 相似文献
246.
Marilyn P. Arnone Ruth V. Small Sarah A. Chauncey H. Patricia McKenna 《Educational technology research and development : ETR & D》2011,59(2):181-198
This paper identifies the need for developing new ways to study curiosity in the context of today’s pervasive technologies
and unprecedented information access. Curiosity is defined in this paper in a way which incorporates the concomitant constructs
of interest and engagement. A theoretical model for curiosity, interest and engagement in new media technology-pervasive learning
environments is advanced, taking into consideration personal, situational and contextual factors as influencing variables.
While the path associated with curiosity, interest, and engagement during learning and research has remained essentially the
same, how individuals tackle research and information-seeking tasks and factors which sustain such efforts have changed. Learning
modalities for promoting this theoretical model are discussed leading to a series of recommendations for future research.
This article offers a multi-lens perspective on curiosity and suggests a multi-method research agenda for validating such
a perspective. 相似文献
247.
David D. Williams Joseph B. South Stephen C. Yanchar Brent G. Wilson Stephanie Allen 《Educational technology research and development : ETR & D》2011,59(6):885-907
This study employed a qualitative research design to investigate how instructional designers use evaluation in everyday design
practice. While past research has examined how designers spend their time, how they generally make decisions, and expert-novice
differences, little attention has been paid to use of context, input, process, or product evaluation, from the perspective
of practicing designers. Based on interviews of practitioners, our findings included ten themes regarding how designers use
evaluation to improve their products. While these results substantiate to some degree the claim that practitioners believe
clients will not pay for formal evaluations, they also suggest that practitioners use evaluation in important but less formal
ways. Other conclusions regarding the role of evaluation in design are provided and future directions for training and research
are discussed. 相似文献
248.
Kushalnagar P Topolski TD Schick B Edwards TC Skalicky AM Patrick DL 《Journal of deaf studies and deaf education》2011,16(4):512-523
Given the important role of parent-youth communication in adolescent well-being and quality of life, we sought to examine the relationship between specific communication variables and youth perceived quality of life in general and as a deaf or hard-of-hearing (DHH) individual. A convenience sample of 230 youth (mean age = 14.1, standard deviation = 2.2; 24% used sign only, 40% speech only, and 36% sign + speech) was surveyed on communication-related issues, generic and DHH-specific quality of life, and depression symptoms. Higher youth perception of their ability to understand parents' communication was significantly correlated with perceived quality of life as well as lower reported depressive symptoms and lower perceived stigma. Youth who use speech as their single mode of communication were more likely to report greater stigma associated with being DHH than youth who used both speech and sign. These findings demonstrate the importance of youths' perceptions of communication with their parents on generic and DHH-specific youth quality of life. 相似文献
249.
E. K. H. Saitta M. A. Bowdon C. L. Geiger 《Journal of Science Education and Technology》2011,20(6):790-795
Technology was integrated into service-learning activities to create an interactive teaching method for undergraduate students
at a large research institution. Chemistry students at the University of Central Florida partnered with high school students
at Crooms Academy of Information Technology in interactive service learning projects. The projects allowed UCF students to
teach newly acquired content knowledge and build upon course lecture and lab exercises. Activities utilized the web-conferencing
tool Adobe Connect Pro to enable interaction with high school students, many of whom have limited access to supplemental educational
opportunities due to low socioeconomic status. Seventy chemistry I students created lessons to clarify high school students’
misconceptions through the use of refutational texts. In addition, 21 UCF students enrolled in the chemistry II laboratory
course acted as virtual lab partners with Crooms students in an interactive guided inquiry experiment focused on chemical
kinetics. An overview of project’s design, implementation, and assessments are detailed in the case study and serve as a model
for future community partnerships. Emerging technologies are emphasized as well as a suggested set of best practices for future
projects. 相似文献
250.
Teacher self-efficacy refers to the beliefs teachers hold regarding their capability to bring about desired instructional outcomes and may be helpful for understanding and addressing critical issues such as teacher attrition and teacher use of research-supported practices. Educating students with autism likely presents teachers with some of the most significant instructional challenges. The self-efficacy of 35 special education teachers of students with autism between the ages of 3 to 9 years was evaluated. Teachers completed rating scales that represented self-efficacy and aspects of the following 3 of Bandura's 4 sources of self-efficacy: (1) sense of mastery, (2) social persuasions, and (3) physiological/affective states. Significant associations were observed between physiological/affective states and self-efficacy, but no associations were observed for the other sources. 相似文献