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181.
Gano-Overway Lori A.; Newton Maria; Magyar T. Michelle; Fry Mary D.; Kim Mi-Sook; Guivernau Marta R. 《Canadian Metallurgical Quarterly》2009,45(2):329
Understanding what factors influence positive youth development has been advocated by youth development researchers (P. L. Benson, 2006; J. S. Eccles & J. A. Gootman, 2002). Consequently, the purpose of this study was to examine whether perceptions of a caring youth sport context influenced prosocial and antisocial behavior through efficacy-related beliefs, that is, positive and negative affective self-regulatory efficacy (ASRE) and empathic self-efficacy (ESE). Multiethnic youths taking part in summer sport programs (N = 395) completed a questionnaire that measured perceptions of the caring climate, ESE, ASRE, and social behavior. Structural equation modeling was used to test whether ASRE and ESE mediated the relationship between caring and social behaviors. Findings revealed that perceptions of caring positively predicted ASRE and ESE. In turn, positive ASRE positively predicted ESE. Prosocial behaviors were positively linked to ESE, whereas antisocial behaviors were negatively predicted by positive ASRE. The results suggest that caring influences prosocial and antisocial behavior because such contexts develop youths' ability to monitor, manage, and control positive affect, which in turn enhances their belief in their ability to empathize. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
182.
Internet based data collection methods have many advantages for psychological assessment when compared with more traditional paper formats, including, reduced costs, and greater convenience for both the researcher and the participant. However, prior to the wide-spread adoption of these methods, equivalence with paper tests formats must be established. The present study compared questionnaire data from the computer with that from a traditional paper format in a sample of college students both directly and through an opinion survey. Three types of questionnaires that represent distinct areas commonly assessed in psychological research included: quality of life (SF-36), depression (BDI-II) and personality (NEO). A within-subjects design counterbalanced order across the computer and paper formats. Overall the findings showed no differences for the Neuroticism and Extraversion facts of the NEO, for the BDI and for the subscales and composite scores of the SF-36. Significant differences were found between the paper and computer formats for the Openness, Agreeableness, and Conscientiousness facets of the NEO. Additionally, the computer was perceived to be convenient, user-friendly, comfortable, and secure. Results suggest that a computerized format is an efficient way to conduct quality of life research, especially for the assessment of distress levels and quality of life. 相似文献
183.
Andy Dong Mary Lou Maher Mi Jeong Kim Ning Gu Xiangyu Wang 《Automation in Construction》2009,18(6):814-824
Real-time, rich-media data communication between the construction site and the off-site design office is becoming one of the important research areas in information technology for construction. This paper presents the concept of a telematic digital workbench, a horizontal tabletop user interface integrating mobile computing and wireless communication to facilitate synchronous construction site to office collaboration. We demonstrate the capabilities and potentials of this system concept for construction defect management. The on-site crew uses a handheld mobile device to collect defect information and transfers the information to the design office through wireless communication by sending the information to a database listener. The digital workbench application monitors the database and synchronizes the location of the visual information on the site with the 3D model on the server. Integrated with 3D viewing capability in a CAD system, designers can interact with the combined model/site data using a horizontal and vertical screen. A case study compared the telematic digital workbench against paper-based and Pocket PC-based methods for defect management in a controlled laboratory experiment. The case study results show that the telematic digital workbench has the potential to improve the accuracy of matching site data to digital data and reduce information loss between site and office collaboration. 相似文献
184.
Claire M Postlethwaite Tiffany M Psemeneki Jangir Selimkhanov Mary Silber Malcolm A MacIver 《Journal of the Royal Society Interface》2009,6(34):417-433
Animal behaviour arises through a complex mixture of biomechanical, neuronal, sensory and control constraints. By focusing on a simple, stereotyped movement, the prey capture strike of a weakly electric fish, we show that the trajectory of a strike is one which minimizes effort. Specifically, we model the fish as a rigid ellipsoid moving through a fluid with no viscosity, governed by Kirchhoff's equations. This formulation allows us to exploit methods of discrete mechanics and optimal control to compute idealized fish trajectories that minimize a cost function. We compare these with the measured prey capture strikes of weakly electric fish from a previous study. The fish has certain movement limitations that are not incorporated in the mathematical model, such as not being able to move sideways. Nonetheless, we show quantitatively that the computed least-cost trajectories are remarkably similar to the measured trajectories. Since, in this simplified model, the basic geometry of the idealized fish determines the favourable modes of movement, this suggests a high degree of influence between body shape and movement capability. Simplified minimal models and optimization methods can give significant insight into how body morphology and movement capability are closely attuned in fish locomotion. 相似文献
185.
Stachowski Alicia A.; Kaplan Seth A.; Waller Mary J. 《Canadian Metallurgical Quarterly》2009,94(6):1536
Organizations increasingly rely on teams to respond to crises. While research on team effectiveness during nonroutine events is growing, naturalistic studies examining team behaviors during crises are relatively scarce. Furthermore, the relevant literature offers competing theoretical rationales concerning effective team response to crises. In this article, the authors investigate whether high- versus average-performing teams can be distinguished on the basis of the number and complexity of their interaction patterns. Using behavioral observation methodology, the authors coded the discrete verbal and nonverbal behaviors of 14 nuclear power plant control room crews as they responded to a simulated crisis. Pattern detection software revealed systematic differences among crews in their patterns of interaction. Mean comparisons and discriminant function analysis indicated that higher performing crews exhibited fewer, shorter, and less complex interaction patterns. These results illustrate the limitations of standardized response patterns and highlight the importance of team adaptability. Implications for future research and for team training are included. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
186.
187.
Ken Donaldson Paul JA Borm Vincent Castranova Mary Gulumian 《Particle and fibre toxicology》2009,6(1):13
In vitro studies with particles are a major staple of particle toxicology, generally used to investigate mechanisms and better understand
the molecular events underlying cellular effects. However, there is ethical and financial pressure in nanotoxicology, the
new sub-specialty of particle toxicology, to avoid using animals. Therefore an increasing amount of studies are being published
using in vitro approaches and such studies require careful interpretation. We point out here that 3 different conventional
pathogenic particle types, PM10, asbestos and quartz, which cause diverse pathological effects, have been reported to cause very similar oxidative stress
effects in cells in culture. We discuss the likely explanation and implications of this apparent paradox, and its relevance
for testing in nanotoxicology. 相似文献
188.
Richard Howey Melvyn Quan Nicholas J. Savill Louise Matthews S?ren Alexandersen Mark Woolhouse 《Journal of the Royal Society Interface》2009,6(39):835-847
This paper investigates the early viral dynamics of foot-and-mouth disease (FMD) within infected pigs. Using an existing within-host model, we investigate whether individual variation can be explained by the effect of the initial dose of FMD virus. To do this, we consider the experimental data on the concentration of FMD virus genomes in the blood (viral load). In this experiment, 12 pigs were inoculated with one of three different doses of FMD virus: low; medium; or high. Measurements of the viral load were recorded over a time course of approximately 11 days for every 8 hours. The model is a set of deterministic differential equations with the following variables: viral load; virus in the interstitial space; and the proportion of epithelial cells available for infection, infected and uninfected. The model was fitted to the data for each animal individually and also simultaneously over all animals varying only the initial dose. We show that the general trend in the data can be explained by varying only the initial dose. The higher the initial dose the earlier the development of a detectable viral load. 相似文献
189.
Mary C.F. Alves Severino J.G. Lima José W.M. Espinosa Luiz E.B. Soledade Iêda M.G. Santos 《Materials Letters》2009,63(1):118-120
Strontium stannate (SrSnO3), a perovskite material, was synthesized by the polymeric precursor method, with different routes to eliminate organic matter. The utilization of pure oxygen for the elimination of organic matter changed the Raman spectra, especially in the low frequency region. Some peaks, which were previously assigned to the perovskite phase, were not noticed when the carbonate amount was lower. On the other hand, the profile of the IR spectra and XRD patterns did not change. These results suggest that carbonate may be present inside the perovskite lattice. 相似文献
190.
Gibbons Mary Beth Connolly; Crits-Christoph Paul; Barber Jacques P.; Wiltsey Stirman Shannon; Gallop Robert; Goldstein Lizabeth A.; Temes Christina M.; Ring-Kurtz Sarah 《Canadian Metallurgical Quarterly》2009,77(5):801
The goal of this article was to examine theoretically important mechanisms of change in psychotherapy outcome across different types of treatment. Specifically, the role of gains in self-understanding, acquisition of compensatory skills, and improvements in views of the self were examined. A pooled study database collected at the University of Pennsylvania Center for Psychotherapy Research, which includes studies conducted from 1995 to 2002 evaluating the efficacy of cognitive and psychodynamic therapies for a variety of disorders, was used. Patient samples included major depressive disorder, generalized anxiety disorder, panic disorder, borderline personality disorder, and adolescent anxiety disorders. A common assessment battery of mechanism and outcome measures was given at treatment intake, termination, and 6-month follow-up for all 184 patients. Improvements in self-understanding, compensatory skills, and views of the self were all associated with symptom change across the diverse psychotherapies. Changes in self-understanding and compensatory skills across treatment were predictive of follow-up symptom course. Changes in self-understanding demonstrated specificity of change to dynamic psychotherapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献