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What is the relationship between resilience and perceived levels of workplace stress among middle leaders in education?
Get PDF© 2024 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.According to the UK’s Health and Safety Executive (HSE), there has been a 36.5% rise in reported cases of work-related stress between 2018/19 and 2019/20, to over 822,000 individual cases. Europe stress-related absence was second only to musculoskeletal disorders, with estimated work-related stress costing European companies 20 billion euros per year and accounted for nearly 60% of lost working days. This paper focuses on the under-researched area of stress among middle leaders in education. While it is widely reported that teachers face high levels of stress, as a result of organisational pressures, there is a paucity of research on middle leaders. This paper considers whether there will be a significant negative relationship between self-reported levels of resilience and self-reported levels of stress amongst 61 middle leaders. The two sets of data were subjected to cross-correlational quantitative analysis to establish the strength of the relationships between each of the six dimensions of resilience on perceived stress. Among the findings, a key result was that the question in the title was answered, namely that high resilience results in low stress in middle leaders in education. However, it was more nuanced than this and there were factors such as levels of peer support and an individual’s perception of their future which did contribute to a reduction in perceived levels of stress. The findings suggest that senior leaders in education have a greater impact on middle leaders’ levels of resilience and perceived levels of stress than they may think.n/
Assessment of performance of the profilers provided in the OECD QSAR toolbox for category formation of chemicals
Get PDFGrowing restrictions and bans on animal testing for chemical safety assessment under different regulations have led to an increasing use of alternative methods. Read-across is one of the major approaches used for this purpose, which relies on the identification of toxicological hazards of a data-poor or untested (target) chemical from data on other already-tested (source) similar chemicals. This requires the target substance to be first assigned to a group or category of ‘similar’ chemicals. The ‘similarity’ may be in terms of structural features alone, or in combination with certain rules that are based on mechanistic and/or toxicological aspects. In this regard, the OECD QSAR toolbox—a major free-access in silico platform—is widely used to derive toxicity predictions for a range of (eco) toxicological endpoints. The Toolbox allows the user to identify a set of similar chemicals (analogues) by computational ‘profilers’ that incorporate different structural alerts, or a combination of structural alerts and physicochemical and/or toxicokinetic rules relevant to a specific toxicological endpoint. The overall aim of this study was to assess the performance of the in silico profilers provided in the OECD QSAR Toolbox for reliability for identifying chemical analogues for category formation in a number of high-quality databases on mutagenicity, carcinogenicity, and skin sensitisation. The study also aimed to identify the reasons for any limitations in the performance of the profilers, and propose ways to improve their overall accuracy. The results showed that whilst some structural alerts are fit-for-purpose as such within the acceptable limits, others need refinement or a consideration for their possible exclusion from the profiler. Such refinements are imperative for a reliable use of the profilers in read-across and grouping/categorisation for classification, labelling and risk assessment of chemicals.Unfunde
Application of piezoelectric transducers in multifunctional engineering structures
Get PDFThis thesis studied the fabrication of piezoelectric transducers and the engineering structural design in pursuit of enhanced piezoelectric behaviour. The research investigated sandwich-based piezoelectric energy harvesters, and a macro fibre composite (MFC) patch as a piezoelectric element. Finite element models of the sandwich structures were established in COMSOL Multiphysics, where the natural frequencies of the first bending modes and the open-circuit voltage at the natural frequencies were predicted. The difference between the numerical voltage prediction and the experimental measurement is within 10%, so that the experimental measurement is able to validate the numerical calculation. It was found that the sandwich with optimised core cellular design, namely the re-entrant honeycomb, could harvest 24.4 μW under base excitation of 1 g p-p magnitude at a first bending mode resonant frequency. Further optimisation on the re-entrant honeycomb core was conducted by introducing functional grading, in pursuit of further piezoelectric energy harvesting performance. Grading was conducted on the re-entrant honeycomb, by varying the cellular wall angle and the optimum grading scheme was found to have a linear variation from 60 ° at the bottom surface, to 45 ° at the top surface. Similarly, the finite element models of sandwiches with functional graded design were established, and it has been found that the experimental result can validate the numerical prediction. It also consisted of a spin-coated P(VDF-TrFE) transducer and sandwich with the optimised graded cellular core producing a maximum 158.7 nW at 2g p-p acceleration.
Moreover, a screen-printing system was built, with fully functioning screen exposure, washing, and substrate clamping units. A screen of 15-200 mesh was selected for P(VDF-TrFE) due to a high paste deposition efficiency. The screen-printed piezoelectric devices were assessed for the structural health monitoring of carbon fibre, and glass fibre reinforced composite panels. When the printed piezoelectric transducers were used as both an emitter and a sensor, the dynamic modes could not be captured by the frequency response function spectrum. When a printed transducer was replaced by a macro fibre composite, the modal information was obtained, and the variation of critical modal peaks was observed after the composite panels were impacted at 5 J for once and twice. It was also observed that the printed transducer behaved more effectively as a sensor than an emitter. These observations demonstrated the feasibility of printed piezoelectric transducers for structural health monitoring applications.
To enhance the piezoelectric property of the printed transducer, BaTiO3 particles were added into the P(VDF-TrFE) matrix. The optimised concentration for the best piezoelectric coefficient was found to be 5 wt% BaTiO3 in relation to P(VDF-TrFE) polymers. At the optimised concentration, the screen-printed piezoelectric generator exhibited a piezoelectric constant d33 of -33.90 pC/N, dielectric constant of 17.05, and the Young’s modulus of 1.35 GPa. The measurement was used as the material properties of the piezoelectric elements in the finite element models of the smart sandwich energy harvesters. The numerically calculated natural frequencies of the first bending modes and the open-circuit voltage were well validated by the experimental result. Combining the optimised screen-printed piezoelectric harvester with carbon and glass fibre reinforced composite panels, resulted in a measured maximum power output between 2.9 μW and 3.8 μW. This power was generated under 1 g peak-peak (p-p) acceleration at the first bending mode resonant frequency. To demonstrate real applications of harvested energy, a commercial accelerometer was powered by a smart composite energy harvester. The smart composite energy harvester was excited at 5 g peak-peak acceleration and connected to a 100 μF capacitor via a full-bridge rectifier. The energy stored in the capacitor was used to power the accelerometer, and successful measurement was demonstrated.
A further development included a screen-printed nonlinear harvester for energy harvesting, where the printed generator was combined with a buckled Duffing nonlinear oscillator with clamp-clamp configuration. The buckled beams were prototyped into rectangular and cellular configurations. The rectangular and cellular configurations provided a maximum power of 0.66 and 0.93 μW, respectively
Multiphysics and Multiscale Building Physics: Proceedings of the 9th International Building Physics Conference (IBPC 2024) Volume 2: Urban Physics and Energy Efficiency
No full textThis version of the contribution has been accepted for publication, after peer review (when applicable) but is not the Version of Record and does not reflect post-acceptance improvements, or any corrections. The Version of Record is available online at: http://dx.doi.org/10.1007/978-981-97-8309-0_77. Use of this Accepted Version is subject to the publisher’s Accepted Manuscript terms of use https://www.springernature.com/gp/open-research/policies/accepted-manuscript-terms.With high energy prices, more households in fuel poverty and space heating accounting for significant amounts of global CO2 emissions, every effort is required to improve the efficacy and efficiency of building heating systems. There is an opportunity to reduce global CO2 emissions and energy demand within domestic and commercial applications by better utilising heating events. During periods of inactivity, setpoints are often reduced to conserve energy. This decreases building fabric temperature, which must be restored during working hours. This paper quantifies how heating events interact, specifically considering their contribution to subsequent heating events to inform decisions on heating schedules. Using a validated dynamic room model representing a typical UK domestic property, the relationship between room temperature, room temperature history, building fabric and surrounding conditions on the coupling of adjacent heating events was explored. The amount of energy that is usefully retained for the subsequent heating event depends significantly on the duration of the previous heating and cooling periods. For example, a day-long heating event with four heating periods of 1.5 hours (duty cycle of 0.25), consumes 9.4% more energy than a single 6.0 hour heating period. A small energy pulse was used in the model to track the interactions between specific heating events. It showed that the useful contribution of a heating event to future heating events depended on the time temperature history of the room, due to the dynamic thermal behaviour of the building fabric.Endo Enterprises (UK) Ltd; Sustainable Futures Scholarship; Cheshire and Warrington 4.0 project through LJMU (RA006092-MEC20/16
Archaeo-media: breaking the binary and building agency in archaeological news reporting
Get PDF© 2024 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.The role of news media in the dissemination of archaeological research isbeginning to receive some attention, but this is inadequate when consideringthe scale of the news media as a tool for public archaeology and mass-distribution of archaeological research in digital news sites. Archaeologyneeds to urgently address this oversight and begin to construct appropriateand sustainable working relationships with the news media, founded ona critical evaluation of current strategies, to regulate the information that isdisseminated through this medium. This paper takes a British perspective,though the themes and necessary improvements have global significance.I suggest that we begin to appreciate the role of the archaeologist in theconstruction of knowledge through the mass media by embracing ‘archaeo-media’- a neologism here proposed to explore the intersections and interac-tions between archaeology and news media.Unfunde
The Liberty of Whitby Strand: The Origins and Significance of a Jurisdictional Immunity
Get PDF© The Author(s) 2024. Published by Oxford University Press.The medieval abbey at Whitby, North Yorkshire, controlled a jurisdictional immunity from royal administration, which was territorial and was known as the Liberty of Whitby Strand. Since Frederick William Maitland, historians have analysed such jurisdictional immunities as an index of royal authority and power. However, the surviving documentation for jurisdictional immunities means that it is often difficult to establish precisely when they were created or what franchises they included. Whitby Abbey claimed that the Liberty of Whitby Strand originated in a grant of King William I and this was accepted by the Victoria County History at the beginning of the twentieth century. Since then, the Liberty has been almost completely ignored. This article revisits the evidence, suggesting that it is possible to pinpoint its origins with rare precision. It argues that the Whitby monks forged a series of charters to persuade King Richard I and King John to transform a narrower portfolio of franchises into the wider territorial Liberty. This article further considers the politics surrounding its creation under Richard and John, and its implications for our understanding of royal authority and power.N/
Perspectives of Time
Get PDFA poem in repsonse to the All Our Relations project funded by Malmö Theatre Academy and Lund University. The work was undertaken in Eastern Sweden over the course of several days working on eco-pedagogical approaches
Assessment of the demographic burden of epidemics and diseases within the African Sub-Region: A review of recent epidemiological data, responses, and resultant psychosocial risk tendencies
Get PDFBackground: Over the past few decades, epidemic outbreaks and disease occurrences have become more frequent and widespread in Africa, posing challenges for poor countries in the region and impacting vulnerable populations. Limited resources, inadequate healthcare infrastructure, socioeconomic inequalities, malnutrition, mass gatherings, and lack of proper sanitation and hygiene contribute to Africa’s high burden of epidemics and infectious diseases such as cholera, measles, monkeypox, Ebola viral disease, and COVID-19. This paper reviewed epidemic outbreaks and diseases transmitted through intimate contact in Africa and their impacts on vulnerable populations. Methods: A narrative review approach was adopted to gather and analyze the relevant literature on epidemic outbreaks in African sub-regions. The review encompassed causes, transmission patterns, demographic impact, community susceptibility, preventive measures, and psychosocial risk-taking behaviors. Results: This study emphasizes the importance of addressing the causes of response lapses and the resulting human, material, and economic losses in the region. Effective preventive measures include disease surveillance, early mitigation strategies, contact tracing, personal protective measures, improved political and public health leadership, and socioeconomic equity. However, the review highlights challenges in implementing these measures effectively due to limited resources, delayed detection, and difficulties in scaling up response solutions. Conclusions: There is a need for a comprehensive approach involving health departments, infrastructure development, and addressing socioeconomic factors.Unfunde
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