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Quintuplet condensation in the skyrmionic insulator Cu<sub>2</sub> OSeO<sub>3</sub> at ultrahigh magnetic fields
No full textWe report ultrahigh magnetic field Faraday rotation results on the chiral helimagnet Cu2OSeO3, the first Mott insulator showing skyrmion lattice phases and a linear magnetoelectric effect. Between 180 and 300 T, we find signatures of a Bose-Einstein condensation of magnons, which can be described as a canted XY ferrimagnet. Because of the magnetoelectric coupling, the transverse magnetic order of the individual Cu2+ spins is accompanied by a characteristic domelike electric polarization which is crucial for the observation of the condensate via the Faraday rotation effect.</p
Scalable platform enabling reservoir computing with nanoporous oxide memristors for image recognition and time series prediction
No full textTypical mammal brains have some form of random connectivity between neurons. Reservoir computing, a neural network approach, uses random weights within its processing layer along with built‐in recurrent connections and short‐term, fading memory, and is shown to be time and training efficient in processing spatiotemporal signals. Here we prepared a niobium oxide‐based thin film memristor device with intrinsic structural inhomogeneity in the form of random nanopores and performed computational tasks of XOR operations, image recognition, and time series prediction and reconstruction. For the latter task we chose a complex three‐dimensional chaotic Lorenz‐63 time series. By applying three temporal voltage waveforms individually across the device and training the readout layer with electrical current signals from a three‐output physical reservoir, we achieved satisfactory prediction and reconstruction accuracy in comparison to the case of no reservoir. This work highlights the potential for scalable, on‐chip devices using all‐oxide reservoir systems, paving the way for energy‐efficient neuromorphic electronics dealing with time signals.</p
AI-Assisted AM for dimensionally accurate ceramic vat-photopolymerisation
No full textCeramic fabrication via bottom-up vat-photopolymerisation additive manufacturing (AM) offers the inherent advantages of AM technologies, including high geometric precision and the capacity to realise complex architectures. Nonetheless, this approach introduces unique challenges that demand in-depth investigation. This PhD research addresses the critical barriers associated with ceramic vat-photopolymerisation and proposes strategies, enhanced by artificial intelligence (AI) algorithms, for the production of dimensionally accurate bulk ceramic components. The research is structured in three stages, each focusing on a key step in the ceramic vat-photopolymerisation process. The first stage is developing a binder formulation; the second examines suspension stability and 2D dimensional accuracy; while the third investigates post-processing shrinkage, with emphasis on the effects of geometry and print parameters. In each stage, experimental datasets were generated and supervised machine learning (ML) algorithms were employed to predict key material or process properties. Each phase of the research was systematically designed and executed with the aim of producing peer-reviewed journal publications. The primary technical challenge lies in the development of a photocurable resin compatible with ceramic suspensions that combines low viscosity with sufficient mechanical strength. As such, the careful selection and optimisation of resin constituents are critical. A full factorial design of experiments was employed to assess the influence of three different monomers/oligomers, each at varying concentrations, on selected binder properties. Simultaneously, supervised ML models like support vector machines, decision trees, and artificial neural networks were developed to predict essential binder characteristics, including binder viscosity and the ultimate tensile strength (UTS) of green bodies. The photocurable ceramic suspension comprises the optimised binder, ceramic powder, and various functional additives. Dispersants play a crucial role in covering ceramic particles to prevent sedimentation and agglomeration during printing. Effective particle dispersion also contributes to a reduction in overall slurry viscosity. Six dispersants were evaluated at different concentrations to determine their effects on suspension rheology. 3 mol% yttria-stabilised zirconia (YSZ) was selected as the model ceramic material, despite its high refractive index posing challenges for UV-based curing due to increased light scattering. This scattering often results in overcuring, thereby compromising dimensional accuracy. To address this, optimisation of ceramic particle morphology, formulation composition, and print parameters was undertaken, along with the addition of UV absorbers to minimise overcuring. Moreover, ML based models were developed to predict 2D dimensional errors in ceramic green parts, enhancing both understanding and mitigation of lateral inaccuracies. Green bodies produced via vat-photopolymerisation consist of a polymer matrix encapsulating ceramic particles. To obtain dense, functional ceramics, post-processing via debinding and sintering is required. These processes induce shrinkage, significantly affecting 3D geometric accuracy. The influence of printing and geometric parameters on shrinkage behaviour was systematically investigated. Variables such as infill type and density, two layer thicknesses, and three build orientations were studied to understand their role in shrinkage dynamics. While traditional approaches to shrinkage analysis and estimations are grounded in sintering theory and rely on material and process parameters, this study employed supervised ML models to predict shrinkage factors based on selected input variables, offering a data-driven alternative for enhanced dimensional control. In conclusion, this PhD research demonstrates the critical role of data-driven modelling in advancing ceramic additive manufacturing via vat-photopolymerisation. By integrating experimental data with supervised machine learning algorithms, the work successfully predicted key properties across the entire production chain, from binder formulation and slurry stability to dimensional accuracy and sintering shrinkage. Traditional empirical and theoretical approaches often fall short in capturing the complex, multivariable interactions inherent in AM processes. In contrast, data-driven models enable the estimation by material and process parameters with greater accuracy.</p
Job stress and counterproductive work behaviours: the roles of negative affect states, vulnerable and grandiose narcissism
No full textDrawing on the stressor-emotions model, this study examines the effect of job stress on employee counterproductive work behaviours (CWB) via negative affect states. In line with the conservation of resources theory, it also explores the moderating roles of vulnerable and grandiose narcissism in the job stress–negative affect link. Two-wave survey data were collected from 358 full-time Nigerian employees across various organisations. Regression analysis tested the direct relationships, while mediation and moderation hypotheses were assessed using bootstrapping methods in PROCESS macro. Findings show that job stress is positively related to negative affect states, which in turn increase CWB. Negative affect states mediate the relationship between job stress and CWB. Moreover, the indirect effect of job stress on negative affect states is stronger for employees high in vulnerable and grandiose narcissism. These findings offer practical insights for organisations seeking to reduce CWB and foster positive work behaviours. Targeted job stress interventions ranging from proactive job redesign, stressor reduction and mindfulness training, to recovery-focused counselling are recommended. Additionally, tailored support for narcissistic employees through empathetic communication, mentoring, and promoting a culture of openness can buffer emotional reactivity and reduce CWB.</p
Economic performance in buyer-seller relationships: examining the roles of asymmetric power sources, sustainability orientation and relationship quality
No full textBuilding on the social exchange theory, this study examines how asymmetric power sources (mediated, non-mediate and reward) influence sustainability orientation in buyer-seller relationships that affect economic performance outcomes while relationship quality moderates the relationship between asymmetric power sources and sustainability orientation. Lisrel is used to analyse data from a dyadic survey of relationships of buyers and sellers. The proposed model is empirically tested using a sample of 436 companies from the United States. Results demonstrates that mediated power sources negatively affect partners’ sustainability orientation (SO), non-mediated power sources positively affect partners SO and reward power positively affect partner’s SO all in which affects economic performance outcomes, while relationship quality positively moderates the impact of asymmetric power use on SO while buyer-seller relationships typically emerge in the context of power asymmetry. The research contributes to a clearer understanding of the role of asymmetric power sources in shaping sustainability orientation that affects economic performance outcomes within sustainable business to business (B2B) relationships.</p
Seeking immortality: an empirical exploration of the significance of work for the non-religious
No full textThis paper draws on in-depth interviews to explore whether work is metaphysically meaningful to ‘Nones’: those who do not have faith in religious traditions or spiritual movements. In particular, it asks how this meaning is a reflection of their beliefs, and why work is metaphysically meaningful if they deny religious and/or spiritual conceptualisations of existence. It argues that although the beliefs held by ‘Nones’ vary considerably, work remains an inherently metaphysical endeavour that provides a means of mediating, alleviating or obscuring their unresolved existential anxieties provoked by finitude. These arguments are theoretically framed through Becker’s notion of ‘symbolic immortality’ (1973) to suggest that regardless of the relationship ‘Nones’ have with finitude, work enables ‘Nones’ to reimagine their existence as infinite. In doing so, it considers the ethicality of ‘life-affirming’ contemporary managerial approaches and corporate cultures that sustain fantasies of symbolic immortality.</p
Supplementary information files for "A transient simulation study of a reversible solid oxide hydrogen planar cell (rSOC): optimising switching strategy between fuel cell and electrolyser modes"
No full textSupplementary files for "A transient simulation study of a reversible solid oxide hydrogen planar cell (rSOC): optimising switching strategy between fuel cell and electrolyser modes"Reversible solid oxide cells (rSOCs) require frequent mode-switching between fuel cell (FC) and electrolysis cell (EC) modes to accommodate the intermittency of renewable energy and the fluctuation of electrical loads. To investigate and optimise the transient behaviour during mode-switching, a 2D transient multiphysics model of an anodesupported planar rSOC cell was developed, incorporating reversible electrochemistry, charge transport, and coupled momentum/mass/heat transport. The model investigates the dual influence of voltage switch and fuel/steam (F/S) ratio on mode switching. The study revealed that higher hydrogen fractions in FC-to-EC transitions and higher steam fractions in EC-to-FC transitions induce larger current overshoots and longer relaxation times. Rapid voltage switching exacerbates overshoot due to insufficient time for species redistribution, while oxygen diffusion emerges as a key limiting factor for switching speed. Coordinated adjustment of gas composition along with voltage switching reduces or eliminates overshoot, with exponential voltage transitions producing smoother and faster responses than linear switching. These findings provide valuable insights for improving rSOC performance, efficiency, and longevity under dynamic operating conditions. The proposed control approaches serve as guidance for developing advanced strategies to integrate rSOC systems effectively with intermittent renewable energy sources.© The Author(s), CC BY 4.0</p
'The university wasn't happy': the knowledges, emotions, and care ethics of 'equity, diversity and inclusion' (EDI) workers in UK higher education
No full textInformed by Higher Education Critical Diversity Studies, this qualitative study used interviews and focus groups with 32 staff and students engaged within Equity, Diversity and Inclusion' (EDI), to generate new empirical evidence about 'EDI work' in the challenging social and regulatory context of UK higher education in the early 2020s. The thesis also offers novel applications of theories of higher education temporalities to EDI work, and considers how Tronto's Ethics of Care (Tronto, 2013) might provide a useful framework for understanding individual and institutional responsibilities around care within the tensions of equity work. By exploring the lived experiences of individuals engaged in various forms of EDI 'work' across multiple universities, this study enabled analysis that contributes to a more complex understanding of the current state of UK university equity efforts. Critical studies into the lived experience of individual 'diversity workers' (Ahmed, 2012a) in the UK university sector in the 2020s have been limited in number and theoretically fragmented. For example, studies have centred on either formal EDI 'practitioner' roles, critiques of Equality Charters, or academic perspectives on social justice or 'inclusive' pedagogies, curriculum, and research. This more holistic research draws on recent post-2016 'Critical Diversity Studies' literature (particularly in the US) to provide deeper insights into the tensions and emotions within EDI work between different actors, informed by critical race- and critical feminist approaches to examining structures of power and inequity. My study engaged with individuals negotiating their roles during a times of sector crisis, and with institutional EDI 'on the precipice' of failure or success. By doing so, it offers new insights into how emotional labour (Hochschild 1979) and care interact with the different knowledge(s) and intersectional identities of EDI workers in HE, and how different individuals navigate their multiple EDI-related roles and responsibilities over time. The study concludes with recommendations for individual and institutional change to mitigate harms to EDI workers, while building a more valued, equitable, and sustainable care-ethical EDI practice.</p
Connected Loughborough Project: Close Down Report
No full textThe Connected Loughborough (CL) project, part of the broader Healthy & Innovative Loughborough (H&IL) initiative, is designed to develop shovel-ready, sustainable transport solutions that enhance connectivity and promote active, healthy lifestyles. Its core focus is the evaluation and redesign of Loughborough’s key East-West transport corridor to improve mobility, reduce carbon emissions, and encourage a shift from car use to active travel modes such as walking and cycling.© the authors</p
Refining the delivery of a 16-form Tai Chi program for chronic ankle instability: a modified Delphi study
No full textObjective: To refine the delivery of a targeted 16-form Tai Chi program for chronic ankle instability (CAI) through a modified Delphi process.Design: Eighteen Tai Chi and sports science experts were invited; ten completed Round 1 and eight of these completed Round 2. To improve geographic diversity, four non-responders outside Mainland China were re-contacted; three completed two rounds, and their feedback was integrated. A self-developed 10-item questionnaire (5-point Likert) was rated. Consensus was defined a priori as ≥70% of ratings 4-5, median≥4, IQR ≤1, and CV ≤0.25. Internal consistency was assessed using Cronbach’s α, and overall agreement using Kendall’s W.Results: In Round 1, all items had median ≥4, but several failed agreement thresholds, prompting revision; α = 0.93 and W = 0.704. In Round 2, all items met consensus criteria; α = 0.94 and W = 0.712. The final delivery set included 10 modifications and 6 additions. Five CAI participants were recruited for preliminary validation; four provided feedback supporting deliverability and informing refinements.Conclusion: This study produced a standardized, consensus-based delivery framework for a 16- form Tai Chi program tailored to CAI. Clinical trials are needed to determine its effectiveness on ankle-related outcomes.</p