214 resultados para Collective efficacy
Resumo:
The present study investigated the impact of teachers' organizational citizenship behaviours (OCBs) on student quality of school life (SQSL) via the indirect effect of job efficacy. A measure of teacher OCBs was developed, tapping one dimension of individual-focused OCB (OCBI – student-directed behaviour) and two dimensions of organization-focused OCB (OCBO – civic virtue and professional development). In line with previous research suggesting that OCBs may enhance job efficacy, as well as studies demonstrating the positive effects of teacher efficacy on student outcomes, we expected an indirect relationship between teachers OCBs and SQSL via teachers' job efficacy. Hypotheses were tested in a multi-level design in which 170 teachers and their students (N=3,057) completed questionnaires. A significant proportion of variance in SQSL was attributable to classroom factors. Analyses revealed that the civic virtue and professional development behaviours of teachers were positively related to their job efficacy. The job efficacy of teachers also had a positive impact on all five indicators of SQSL. In regards to professional development, job efficacy acted as an indirect variable in the prediction of four student outcomes (i.e., general satisfaction, student–teacher relations, achievement, and opportunity) and fully mediated the direct negative effect on psychological distress.
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This study investigated the effects of workload, control, and general self-efficacy on affective task reactions (i.e., demands-ability fit, active coping, and anxiety) during a work simulation. The main goals were: (1) to determine the extent general self-efficacy moderates the effects of demand and control on affective task reactions, and; (2) to determine if this varies as a function of changes in workload. Participants (N=141) completed an inbox activity under conditions of low or high control and within low and high workload conditions. The order of trials varied so that workload increased or decreased. Results revealed individuals with high general self-efficacy reported better demands-abilities fit and active coping as well as less anxiety. Three interactive effects were found. First, it was found that high control increased demands-abilities fit from trial 1 to trial 2, but only when workload decreased. Second, it was found that low efficacious individuals active coping increased in trial 2, but only under high control. Third, it was found that high control helped high efficacious individuals manage anxiety when workload decreased. However, for individuals with low general self-efficacy, neither high nor low control alleviated anxiety (i.e., whether workload increased or decreased over time).
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This volume introduces a collective approach that positions transmedia as a dynamic phenomenon which undergoes constant innovation as it absorbs current trends and advances in its constituent disciplines. The first section, 'Sustaining Future Practices', explores emerging models for defining stakeholder needs, understanding resource requirements and measuring the value and success of transmedia productions. The focus then shifts to 'Intersecting Contexts of Transmedia Practices', which uses the juxtaposition of a diverse collection of case studies to transcend not only the debates about how to define transmedia, but also the professional and disciplinary boundaries that impose artificial constraints upon the way transmedia projects are approached and understood. This inter-disciplinary dialogue aims to promote an ongoing conversation on the challenges and opportunities associated with sustaining this vital creative industry.
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Background This study evaluated the feasibility and preliminary efficacy of a church-based intervention to promote physical activity (PA) in children. Methods The study was conducted in 4 churches located in 2 large metropolitan areas and 2 regional towns in Kansas. Churches in the intervention condition implemented the "Shining Like Stars" physical activity curriculum module during their regularly scheduled Sunday school classes. Churches in the control condition delivered the same content without integrating physical activity into the lessons. In addition to the curriculum, the intervention churches completed a series of weekly family devotional activities designed to promote parental support for PA and increase PA outside of Sunday school. Results Children completing the Shining Like Stars curriculum exhibited significantly greater amounts of MVPA than those in the control condition (20 steps/min vs. 7 steps/min). No intervention effects were observed for PA levels outside of Sunday school or parental support for PA; however, relative to controls, children in the intervention churches did exhibit a significant reduction in screen time. Conclusion The findings confirm that the integration of physical activity into Sunday school is feasible and a potentially effective strategy for promoting PA in young children.
Resumo:
Background This study evaluated the effect of a “move and learn” curriculum on physical activity (PA) in 3- to 5-year-olds attending a half-day preschool program. Methods Classrooms were randomized to receive an 8-week move and learn program or complete their usual curriculum. In intervention classes, opportunities for PA were integrated into all aspects of the preschool curriculum, including math, science, language arts, and nutrition education. Changes in PA were measured objectively using accelerometry and direct observation. Results At the completion of the 8-week intervention, children completing the move and learn curriculum exhibited significantly higher levels of classroom moderate-to-vigorous physical activity (MVPA) than children completing their usual curriculum. Significant differences were also noted for classroom VPA over the final 2 weeks. Conclusion The results suggest that integrating movement experiences into an existing early childhood curriculum is feasible and a potentially effective strategy for promoting PA in preschool children.
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Adequate consumption of fruits and vegetables (FV) is a characteristic of a healthy diet but remains a challenge in nutrition interventions. This cross-sectional study explored the multi-directional relationships between maternal feeding self-efficacy, parenting confidence, child feeding behaviour, exposure to new food and FV intake in a cohort of 277 infants. Mothers with healthy infants weighing ≥2500 g and ≥37 weeks gestation were recruited post-natally from 11 South Australian hospitals. Socio-demographic datawere collected at recruitment. At 6 months postnatal, infantswereweighed and measured, andmothers completed a questionnaire exploring their perceptions of child feeding behaviour and child exposure to newfoods. The questionnaire also included the Short Temperament Scale for Infants, Kessler 10 to measure maternal psychological distress and 5 items measuring maternal feeding self-efficacy. The number of occasions and variety of FV (number of subgroups within food groups) consumed by infants were estimated from a 24-hour dietary recall and 2 days food record. Structural equation modellingwas performed using Mplus version 6.11. Median (IQR) variety scores were 2 (1–3) for fruit and 3 (2–5) for vegetable intake. The most popular FV consumed were apple (n = 108, 45.0%) and pumpkin (n = 143, 56.3%). None of the variables studied predicted the variety of child fruit intake. Parenting confidence, exposure to new foods and child feeding behaviourwere indirectly related to child vegetable intake through maternal feeding self-efficacy while total number of children negatively predicted child vegetable variety (p < 0.05). This highlights the need for addressing antecedents of maternal feeding self-efficacy and the family eating environment as key strategies towards development of healthy eating in children.
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Spreading cell fronts are essential features of development, repair and disease processes. Many mathematical models used to describe the motion of cell fronts, such as Fisher’s equation, invoke a mean–field assumption which implies that there is no spatial structure, such as cell clustering, present. Here, we examine the presence of spatial structure using a combination of in vitro circular barrier assays, discrete random walk simulations and pair correlation functions. In particular, we analyse discrete simulation data using pair correlation functions to show that spatial structure can form in a spreading population of cells either through sufficiently strong cell–to–cell adhesion or sufficiently rapid cell proliferation. We analyse images from a circular barrier assay describing the spreading of a population of MM127 melanoma cells using the same pair correlation functions. Our results indicate that the spreading melanoma cell populations remain very close to spatially uniform, suggesting that the strength of cell–to–cell adhesion and the rate of cell proliferation are both sufficiently small so as not to induce any spatial patterning in the spreading populations.
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Battery/supercapacitor hybrid energy storage systems have been gaining popularity in electric vehicles due to their excellent power and energy performances. Conventional designs of such systems require interfacing dc-dc converters. These additional dc-dc converters increase power loss, complexity, weight and cost. Therefore, this paper proposes a new direct integration scheme for battery/supercapacitor hybrid energy storage systems using a double ended inverter system. This unique approach eliminates the need for interfacing converters and thus it is free from aforementioned drawbacks. Furthermore, the proposed system offers seven operating modes to improve the effective use of available energy in a typical drive cycle of a hybrid electric vehicle. Simulation results are presented to verify the efficacy of the proposed system and control techniques.
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This paper presents a novel battery direct integration scheme for renewable energy systems. The idea is to replace ordinary capacitors of a three-level flying-capacitor inverter by three battery banks to alleviate power fluctuations in renewable generation. This approach eliminates the need for interfacing dc-dc converters and thus considerably improves the overall efficiency. However, the major problem with this approach is the uneven distribution of space vectors which is due to unavoidable unbalance in clamping voltages. A detailed analysis on the effects of this issue and a novel carrier based pulse width modulation method, which can generate undistorted currents even in the presence of unevenly distributed space vectors, are presented in this paper. A charge/discharge controller is also proposed for power sharing and state of charge balancing of battery banks. Simulation results are presented to verify the efficacy of the proposed system, modulation method and power sharing controller.
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Monitoring therapeutic efficacy of antimalarial drugs is important because treatment failure rates are the primary basis for changing antimalarial treatment policy. An important aspect of efficacy studies is the use of PCR genotyping to distinguish recrudescent from new infections. The conclusions reached using this technique might be misleading if there is insufficient parasite diversity or a non-uniform haplotype frequency distribution in the study area. Statistical techniques can be used to overcome this problem, but only when data describing the haplotype frequency distribution are available. Therefore, assessing haplotype frequency and distribution should form an integral part of all studies investigating the therapeutic efficacy of antimalarial treatment regimes.
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We consider a discrete agent-based model on a one-dimensional lattice and a two-dimensional square lattice, where each agent is a dimer occupying two sites. Agents move by vacating one occupied site in favor of a nearest-neighbor site and obey either a strict simple exclusion rule or a weaker constraint that permits partial overlaps between dimers. Using indicator variables and careful probability arguments, a discrete-time master equation for these processes is derived systematically within a mean-field approximation. In the continuum limit, nonlinear diffusion equations that describe the average agent occupancy of the dimer population are obtained. In addition, we show that multiple species of interacting subpopulations give rise to advection-diffusion equations. Averaged discrete simulation data compares very well with the solution to the continuum partial differential equation models. Since many cell types are elongated rather than circular, this work offers insight into population-level behavior of collective cellular motion.
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This research has built on the growing interest in the prosumer in the workplace – prosumers are those users with high technological skills who both produce and consume their own technology solutions. Prosumers are leaders in their industrial or professional fields and who expect to obtain significant benefit from innovating. The literature reveals that commercially attractive products tend to be developed by prosumers who are at the leading edge of important marketplace trends and therefore this group is increasingly important. This study surveyed prosumers across a variety of occupations and workplaces and explored the motivators and personality traits of the prosumer.
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Quantifying the impact of biochemical compounds on collective cell spreading is an essential element of drug design, with various applications including developing treatments for chronic wounds and cancer. Scratch assays are a technically simple and inexpensive method used to study collective cell spreading; however, most previous interpretations of scratch assays are qualitative and do not provide estimates of the cell diffusivity, D, or the cell proliferation rate,l. Estimating D and l is important for investigating the efficacy of a potential treatment and provides insight into the mechanism through which the potential treatment acts. While a few methods for estimating D and l have been proposed, these previous methods lead to point estimates of D and l, and provide no insight into the uncertainty in these estimates. Here, we compare various types of information that can be extracted from images of a scratch assay, and quantify D and l using discrete computational simulations and approximate Bayesian computation. We show that it is possible to robustly recover estimates of D and l from synthetic data, as well as a new set of experimental data. For the first time, our approach also provides a method to estimate the uncertainty in our estimates of D and l. We anticipate that our approach can be generalized to deal with more realistic experimental scenarios in which we are interested in estimating D and l, as well as additional relevant parameters such as the strength of cell-to-cell adhesion or the strength of cell-to-substrate adhesion.
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Portable, water filled road safety barriers are used to provide protection and reduce the potential hazard due to errant vehicles in areas where the road conditions change frequently (e.g. near road work sites). As part of an effort to reduce excessive working widths typical of these systems, a study was conducted to assess the effectiveness of introducing polymeric foam filled panels into the design. Surrogate impact tests of a design typical of such as barrier system were conducted utilising a pneumatically powered horizontal impact testing machine up to impact energies of 7.40 kJ. Results of these tests are utilised to examine the barrier behaviour, in addition to being used to validate a couple FE/SPH model of the barrier system. Once validated, the FE/SPH model it utilised as the basis for a parametric study into the efficacy and effects of the inclusion of polymeric foam filled panels on the performance of portable water filled road safety barriers. It was found that extruded polystyrene foam functioned well, with a greater thickness of the foam panel significantly reducing the impacting body velocity as the barrier began to translate.