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A Privacy-Preserving Auction for Task Offloading and Resource Allocation in UAV-Assisted MEC
Get PDFAs a complementary solution for Mobile Edge Computing (MEC), Unmanned Aerial Vehicles (UAVs) can temporarily provide reliable and flexible offloading services when edge servers are damaged or unavailable. However, existing UAV-assisted MEC systems suffer from issues such as uneven resource allocation, low utilization efficiency, load imbalance, and poor dynamic adaptability, affecting service quality. Moreover, sensitive user equipment (UE) information faces leakage during the computational process of UAVs. How to jointly optimize the scheduling of servers and UAVs for task offloading and resource allocation without compromising UEs' privacy remains a significant challenge. Thus, this paper proposed a privacy-preserving auction framework (namely Prizty) by considering the trajectory of UAVs, their constrained energy and computational capabilities, and the variability in UE distribution. Prizty employs a combinatorial obfuscation method to protect UEs' privacy and links bidding prices to computational resources and energy characteristics. It calls the sub-algorithm WPA to determine the winners by balancing social costs and utility. Theoretical analysis demonstrates that Prizty satisfies truthfulness and individual rationality while maintaining scalability for large-scale resource allocation problems. Extensive experiments on real-world datasets validate Prizty's effectiveness in critical metrics, including offload rate, average service latency, energy consumption, and social cost
Value creation at the pre-selection stage of university study destination : Perspectives of academics, marketing professionals and students in UK HE
Get PDFWith the marketisation of UK HE, grants for universities have been remained largely unchanged over a decade, producing increased competition. Therefore, universities must find ways to create value to attract students. Factors influencing students potential university choice is well researched. While value is attracting increasing research interest in HE, minimal research has been conducted into value creation at the stage before students have chosen their university, the focus of this study. Deploying Ballantyne and Varey’s (2006) value creation model, this research used 32 semi-structured interviews, across 12 UK universities among 3 groups – senior marketing professionals, academics involved in student recruitment and students. Key findings: The universities offer value propositions, integrating choice factors which potential undergraduates then evaluate to see which best delivers the outcomes they seek. Participants conceive of value as transforming lives by undertaking a degree. Regarding value creation activities, the research shows that relationships are developed between academics and students’, influencing their decision to study at that particular university. The relationship between academics and marketing professionals is tested by academic desire to play a greater role in designing the value proposition for potential students. On communication between the university and students there is primarily one-way. However, this is sufficient at the pre-selection stage because although students enact consumer behaviour in assessing university offers, they do not have neo-liberal consumer expectations. That could be a missed opportunity for institutions. There is two-way rather than dialogic communication between marketing professionals and academics, missing an opportunity to gather insights that could enhance the value proposition. The study shows that both tacit and explicit knowledge are used but explicit is more dominant. Trust plays a mediating role within and between value creating activities. Even when there is a value creating activity that is only partially working, trust bridges the gap. The study concludes that Ballantyne and Varey’s (2006) model can be applied to HE, generating insights and highlighting limits. There are opportunities to create and enhance value for potential students. The research establishes the importance of relationships internally and with potential students. Enhanced communication between university staffing groups could lead to more effective knowledge sharing
Growth in Production and Environmental Deposition of Trifluoroacetic Acid Due To Long-Lived CFC Replacements and Anesthetics
No full textAbstract Trifluoroacetic acid (TFA) is a persistent pollutant with potential long-term effects on the environment and on health. Recent studies using ice core records report large increases (up to tenfold) in Arctic TFA deposition since the 1970s, and trends suggest long-lived chlorofluorocarbon (CFC) replacements may be a major source. Here, we use a chemical transport model to examine the global TFA budget arising from CFC replacements–hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons (HFCs)–and inhalation anesthetics. Global TFA deposition from these sources increased ∼3.5-fold from 6.8 (5.9–7.6) Gg/yr in 2000 to 21.8 (18.6–25.0) Gg/yr in 2022, with cumulative deposition reaching 335.5 Gg. We find HCFC-123, HCFC-124, and HFC-134a account for most modeled TFA production and that long-lived CFC replacements account for virtually all of the observed Arctic deposition trend. At lower latitudes, our analysis supports the recent emergence of hydrofluoroolefins (HFOs) as a TFA source. We conclude that increased TFA monitoring is required
Electrochemical properties of layered perovskite for the electrode of symmetrical solid oxide fuel cells
Get PDFIn this study, Co free layered perovskites SmBa(Fe1-xMnx)2O5+d (SBFMn, x = 0, 0.1, 0.3, and 0.5) were proposed as candidate electrode materials for symmetrical solid oxide fuel cells (SSOFCs), and the influence of Mn/Fe ratio on electrochemical performance, electrical conductivity behavior, and structural stability was systematically investigated. Impedance measurements using LSGM based half cells showed that SmBa(Fe0.9Mn0.1)2O5+d (SBFMn 1.8-0.2) exhibited lower area specific resistance in both air and 3.9% hydrogen atmosphere, indicating balanced and enhanced oxygen reduction reaction and hydrogen oxidation reaction activity. Electrical conductivity showed that increasing Mn content led to reduced conductivity in air and nitrogen atmospheres due to weakened M-O-M orbital overlap and decreased Fe4+ derived hole concentration. In contrast, under hydrogen atmosphere, a small degree of Mn incorporation resulted in a relative enhancement of electrical conductivity. X-ray diffraction analysis confirmed that an irreversible cubic to orthorhombic phase transition occurred exclusively under reducing conditions at approximately 450 °C, which is consistent with the conductivity decrease observed during the initial heating process and its subsequent recovery at higher temperatures. These results demonstrate that precise control of the Mn/Fe ratio enables simultaneous optimization of electrochemical activity and structural stability, providing practical design guidelines for layered perovskite electrodes in SSOFC applications
Pharmaceutical pollution from health care : a systems-based strategy for mitigating risks to public and environmental health
No full textHuman pharmaceuticals are increasingly detected in environments around the world, with growing international calls to mitigate the ecological and human health risks posed by these novel entities. Exposure to pharmaceutical pollutants can negatively affect the behaviour, reproduction, and health of wildlife, contributing towards declining ecological health and global biodiversity loss. Pharmaceuticals in the environment are also driving rising levels of antimicrobial resistance, a major public health threat. Developing strategies to mitigate these public and environmental health risks has been greatly limited by diverse and often conflicting stakeholder interests and the need to retain the major human health and socioeconomic benefits that pharmaceuticals provide. In this Personal View, we propose a multistakeholder, systems-based approach for high-income countries to develop transformational national mitigation strategies. Applying this approach to a UK case study highlighted the growing risks caused by the unsustainability of the current UK health-care pharmaceutical system and enabled us to identify 37 synergistic intervention points that target both the tangible easy wins and the deep-rooted social drivers of the issue. We believe our approach will support high-income countries in minimising the public and environmental health risks associated with pharmaceutical pollution, by driving long-term sustainability across the pharmaceutical lifecycle, for a positive pharmaceutical future. [Abstract copyright: Copyright © 2025 The Author(s). Published by Elsevier Ltd.. All rights reserved.
Long-term warming and vegetation change have no impact on microbial resistance to drought, but destabilise microbial communities and microbially-mediated functions
No full textClimate change presents multiple stresses to ecosystems that operate over different timescales, such as long-term warming and short-term drought. It is well established that soil microbial communities are highly responsive to individual stresses, but how they respond combined warming and drought, and how factors such as vegetation change moderate responses, remains uncertain. Here we tested whether long-term passive warming modifies the resistance (amplitude of response) and resilience (degree and duration of recovery) of soil microbial communities to short-term drought. We also tested whether warming effects on microbial resilience to drought are moderated by vegetation composition, and specifically the presence of ericaceous dwarf shrubs, the dominant vegetation type of peatland. This was tested using soil from a nine-year warming and vegetation manipulation experiment established on blanket peatland in northern England. We completed a subsequent laboratory study designed to quantify resistance and resilience of microbial communities and microbial-mediated functions to drought. Neither long-term warming nor shrub removal impacted the resistance of microbial communities to drought. However, resilience of bacterial diversity to drought was decreased by warming (fold change 0.38) and shrub removal (fold change 0.27). Notably the interaction between warming and shrub removal resulted in higher resilience of bacterial diversity than individual treatments (fold change 0.58; warming x shrub removal: p = 0.008). Further, warming and shrub removal individually increased the diversity of fungal communities, and reduced resilience of fungal diversity to drought (fold change of warmed against unwarmed 0.11, shrub removal against control 0.39, combination against control 0.59; warming x shrub removal p = 0.006). Warming also strongly decreased resilience, but not resistance, of nitrogen-based functions to drought, although shrub removal dampened this effect. Our findings demonstrate potential for long-term warming and vegetation change to modify microbial responses to extreme drought events, with implications for peatland carbon and nitrogen cycling under future climate scenarios
Maximising the Potential of University-Business Collaborations for Regional Sustainability through Stakeholder-Centred Evaluation
Get PDFThis thesis examines the critical role of evaluation in university-business collaborations (UBCs) aimed at driving sustainable regional development. Despite widespread recognition of UBCs as key catalysts for sustainability transitions, existing evaluative practices often fail to adequately account for stakeholder diversity, place-based contexts, and the dynamic tensions inherent in collaboration. Through a mixed-methods approach, this research explores how evaluative frameworks can be reshaped to harness tensions in a productive manner which maximises the potential of sustainable collaborations, and thus the potential for sustainable regional impact. The thesis develops and applies multiple conceptual lenses to evaluative methodologies in the context of a 3-year longitudinal study of a university-business collaboration project focused on low-carbon innovation. Given the inherent focus of existing literature on value and practical knowledge, the thesis uses lenses of heterarchy and phronesis to shed new light onto the challenges and opportunities of navigating stakeholder priorities. The findings demonstrate the potential of phronesis-driven (practical wisdom) approaches to foster alignment between global sustainability aims and the priorities of regional stakeholders, supporting the development of place-based innovation which engages regional stakeholders throughout the process. By emphasising the importance of proactive, place-based and stakeholder-centred evaluations, this work contributes to both theory and practice, offering actionable insights for policymakers, researchers, and practitioners engaged in designing and implementing university-business collaborations for sustainability. Taking a step back from evaluative methodologies and frameworks, the aims and outcomes of evaluation itself are critically considered to examine how this can be better harnessed to strengthen collaborations and predispose favourable outcomes for stakeholders. The findings emphasise the potential of considering evaluation from a different perspective, as a tool for not only measuring impact but also shaping collaborative processes to deliver equitable and sustainable outcomes
Insults as a sentence type : A cross-linguistic perspective
No full textThis paper asks whether insults are ever encoded as a distinct sentence type in natural languages, and hence form a distinct grammaticalized Illocution in the languages concerned. To assess this, we designed three mutually independent criteria and applied these to 29 constructions from 23 languages, gathering data via native speaker consultation, corpus searches and published literature. Our results indicate that seven of these constructions are exclusively used for the communicative goal of insulting the addressee, thus providing evidence for the existence of an Insultive Illocution. Moreover, we found evidence of an underspecified Evaluative Illocution in nine languages. We therefore propose that both the Insultive and the Evaluative be added to the inventory of grammaticalized Illocution recognized in Functional Discourse Grammar
On Derived Lie algebras
Get PDFIn this paper we investigate the problem of which Lie algebras appear as the derived algebra of a Lie algebra. We present new results that further develop this study and address two questions raised in a paper concerned with the corresponding problem for groups