143 research outputs found

    ‘Deliberate Preparation’ as an evidence-based focus for primary physical education

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    There is substantial scientific research suggesting the physical and psychological health benefits of a physically active lifestyle. Consequently, governments worldwide prioritize policies, finances, and resources in healthcare, education, and sports sectors to increase mass participation in physical activity. However, practices in physical activity promotion are often not underpinned by evidence-based standardization that is requisite in other domains of epidemiology. The aim of this article is to examine critically the available scientific research on promoting life-long physical activity participation and to propose an evidence-based model for implementation in school physical education. Reasons are discussed as to why programs that integrate physical, psychological, and behavioral skills have been long acknowledged in physical education and physical activity domains but remain lacking in empirical validation. Finally, future directions are suggested that are required to examine the application of this approach to practice in primary-level physical education

    The relationship between the perception of distributed leadership in secondary schools and teachers' and teacher leaders' job satisfaction and organizational commitment

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    This study investigates the relation between distributed leadership, the cohesion of the leadership team, participative decision-making, context variables, and the organizational commitment and job satisfaction of teachers and teacher leaders. A questionnaire was administered to teachers and teacher leaders (n=1770) from 46 large secondary schools. Multiple regression analyses and path analyses revealed that the study variables explained significant variance in organizational commitment. The degree of explained variance for job satisfaction was considerably lower compared to organizational commitment. Most striking was that the cohesion of the leadership team and the amount of leadership support was strongly related to organizational commitment, and indirectly to job satisfaction. Decentralization of leadership functions was weakly related to organizational commitment and job satisfaction

    Microbial fuel cells directly powering a microcomputer

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    © 2019 The Authors Many studies have demonstrated that microbial fuel cells (MFC) can be energy-positive systems and power various low power applications. However, to be employed as a low-level power source, MFC systems rely on energy management circuitry, used to increase voltage levels and act as energy buffers, thus delivering stable power outputs. But stability comes at a cost, one that needs to be kept minimal for the technology to be deployed into society. The present study reports, for the first time, the use of a MFC system that directly and continuously powered a small application without any electronic intermediary. A cascade comprising four membrane-less MFCs modules and producing an average of 62 mA at 2550 mV (158 mW) was used to directly power a microcomputer and its screen (Gameboy Color, Nintendo®). The polarisation experiment showed that the cascade produced 164 mA, at the minimum voltage required to run the microcomputer (ca. 1.850 V). As the microcomputer only needed ≈70 mA, the cascade ran at a higher voltage (2.550 V), thus, maintaining the individual modules at a high potential (>0.55 V). Running the system at these high potentials helped avoid cell reversal, thus delivering a stable level of energy without the support of any electronics

    Long-term performance of a plant microbial fuel cell with Spartina anglica

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    The plant microbial fuel cell is a sustainable and renewable way of electricity production. The plant is integrated in the anode of the microbial fuel cell which consists of a bed of graphite granules. In the anode, organic compounds deposited by plant roots are oxidized by electrochemically active bacteria. In this research, salt marsh species Spartina anglica generated current for up to 119 days in a plant microbial fuel cell. Maximum power production was 100 mW m−2 geometric anode area, highest reported power output for a plant microbial fuel cell. Cathode overpotential was the main potential loss in the period of oxygen reduction due to slow oxygen reduction kinetics at the cathode. Ferricyanide reduction improved the kinetics at the cathode and increased current generation with a maximum of 254%. In the period of ferricyanide reduction, the main potential loss was transport loss. This research shows potential application of microbial fuel cell technology in salt marshes for bio-energy production with the plant microbial fuel cell

    From the lab to the field: Self-stratifying microbial fuel cells stacks directly powering lights

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    The microbial fuel cell (MFC) technology relies on energy storage and harvesting circuitry to deliver stable power outputs. This increases costs, and for wider deployment into society, these should be kept minimal. The present study reports how a MFC system was developed to continuously power public toilet lighting, with for the first time no energy storage nor harvesting circuitry. Two different stacks, one consisting of 15 and the other 18 membrane-less MFC modules, were operated for 6 days and fuelled by the urine of festival goers at the 2019 Glastonbury Music Festival. The 15-module stack was directly connected to 2 spotlights each comprising 6 LEDs. The 18-module stack was connected to 2 identical LED spotlights but going through 2 LED electronic controller/drivers. Twenty hours after inoculation the stacks were able to directly power the bespoke lighting system. The electrical energy produced by the 15-module stack evolved with usage from ≈280 mW (≈2.650 V at ≈105 mA) at the beginning to ≈860 mW (≈2.750 V at ≈300 mA) by the end of the festival. The electrical energy produced by the LED-driven 18-module stack increased from ≈490 mW at the beginning to ≈680 mW toward the end of the festival. During this period, illumination was above the legal standards for outdoor public areas, with the 15-module stack reaching a maximum of ≈89 Lx at 220 cm. These results demonstrate for the first time that the MFC technology can be deployed as a direct energy source in decentralised area (e.g. refugee camps)

    The motivational impact of wearable healthy lifestyle technologies: a self-determination perspective on Fitbits with adolescents

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    Background: Considerable numbers of young people are not meeting physical activity guidelines. Wearable fitness devices can provide opportunities for physical activity promotion. Purpose: The aim of the study was to explore whether wearable healthy lifestyle technologies impacted on adolescents’ (13- to 14-year-olds) motivation for physical activity. Methods: The study was a mixed method sequential design. Participants were 84 adolescents (44 girls, 40 boys) from 6 physical education classes. Pupils were issued with a Fitbit to wear for 8 weeks and completed pre-/posttest questionnaires that assessed motivational regulation and psychological need satisfaction. Adolescents also engaged in focus group interviews after wearing the Fitbit for 8 weeks. Quantitative data were analyzed using a repeated measures multivariate analysis of variance (MANOVA) to explore differences between gender and time. Qualitative data analysis was conducted deductively using self-determination theory. Results: The quantitative findings identified significant reductions in need satisfaction and autonomous motivation and significant increases in amotivation after 8 weeks. Qualitative evidence suggested short-term increases in motivation through feelings of competition, guilt, and internal pressure. Discussion: Findings suggest that healthy lifestyle technology may have negative motivational consequences. Translation to Health Education Practice: Certified Health Education Specialists should support young people to personalize health targets in order to critically engage with normalized health targets

    Towards effective small scale microbial fuel cells for energy generation from urine

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    © 2016 The Authors. Published by Elsevier Ltd. To resolve an increasing global demand in energy, a source of sustainable and environmentally friendly energy is needed. Microbial fuel cells (MFC) hold great potential as a sustainable and green bioenergy conversion technology that uses waste as the feedstock. This work pursues the development of an effective small-scale MFC for energy generation from urine. An innovative air-cathode miniature MFC was developed, and the effect of electrode length was investigated. Two different biomass derived catalysts were also studied. Doubling the electrode length resulted in the power density increasing by one order of magnitude (from 0.053 to 0.580 W m-3). When three devices were electrically connected in parallel, the power output was over 10 times higher compared to individual units. The use of biomass-derived oxygen reduction reaction catalysts at the cathode increased the power density generated by the MFC up to 1.95 W m-3, thus demonstrating the value of sustainable catalysts for cathodic reactions in MFCs
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