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GSK-3β coordinates axonal microtubule organisation through Shot and Tau
Full text linkGlycogen Synthase Kinase 3β (GSK-3β) is a key coordinator of neuronal development and maintenance; hyperactive GSK-3β is linked to neurodevelopmental and -degenerative diseases and therefore a promising therapeutic target. In neurons, GSK-3β coordinates the cytoskeleton by phosphorylating microtubule-binding proteins. In this study, we found that tight regulation of GSK-3β kinase activity is required for the maintenance of parallel microtubule bundles in Drosophila and rat axons. Up- or down-regulation of GSK-3β led to axons forming pathological swellings in which microtubule bundles disintegrated into disorganised, curled microtubules. We identified the microtubule bundling proteins Shot and Tau as key GSK-3β targets and found that GSK-3β exerted its regulatory effect on microtubule bundling through them. GSK-3β regulates the ability of Shot and Tau to attach to microtubules and/or Eb1. Mis-regulation of GSK-3β leads to the loss of Eb1–Shot-mediated guidance of polymerising microtubules into parallel bundles, thus causing disorganisation. We propose microtubule disorganisation as a new explanation how GSK-3β hyperactivity leads to neurodegeneration and why global inhibition of GSK-3β has not been successful in clinical trials for neuronal disorders
Unlocking Effective Crisis Leadership Amidst Healthcare Supply Chain Disruptions: The Nonlinear Effect of Organisational Culture
Full text linkThe healthcare sector's vulnerability to societal disruptions was highlighted by the COVID-19 pandemic and supply chain challenges. This study applies Upper Echelon Theory (UET) to crisis contexts, focusing on Sustainable Development Goal 3 (Good Health and Well-Being). Unlike prior work that emphasised leaders' immediate actions, this research examines how organisational culture influences the link between crisis leadership and healthcare supply chain resilience. Survey data from 179 participants using structural equation modelling (PLS-SEM) reveal a non-linear relationship: balancing flexibility and control in organisational culture is vital for supply chain resilience. Effective crisis leadership, backed by a strong organisational culture, boosts supply chain robustness and adaptability. Additionally, 18 qualitative interviews identified key traits for crisis leaders: communication, transparency, resilience, trust, and empathy. The findings underline the crucial role of crisis leadership and balanced organisational culture in overcoming supply chain disruptions. The study recommends that managers and policymakers cultivate such cultures to enhance resilience. Limitations are noted, and future research should further explore how culture and leadership interact in uncertain environments
Performance Enhancement of Latent Heat Storage Using Extended-Y-Fin Designs
Full text linkThe low thermal conductivity of phase-change materials (PCMs) remains a key limitation in latent heat thermal energy storage systems, leading to slow melting and incomplete energy recovery. To address this challenge, this study explores extended Y-Fin geometries as a novel heat transfer enhancement strategy within a concentric-tube latent heat thermal energy storage configuration. Six fin designs, derived from a baseline Y-shaped structure, were numerically compared to assess their influence on the melting and solidification behavior of stearic acid. A two-dimensional transient enthalpy–porosity model was developed and rigorously verified through grid, temporal, and residual convergence analyses. The results indicate that fin geometry plays a critical role in enhancing heat transfer within the PCM domain. The extended Y-Fin configuration achieved the fastest melting time, 28% shorter than the baseline Y-Fin case, due to improved thermal penetration and bottom-region accessibility. Additionally, the thermal performance was evaluated using nano-enhanced PCMs (10% Al2O3 and CuO in stearic acid) and paraffin wax. The addition of Al2O3 nanoparticles significantly improved thermal conductivity, while paraffin wax exhibited the shortest melting duration due to its lower melting point and latent heat. This study introduces an innovative fin architecture combining extended conduction paths and improved convective reach for efficient latent heat storage systems
A Hybrid Inorganic–Organic Schiff Base-Functionalised Porous Platform for the Remediation of WEEE Polluted Effluents
Full text linkAn inorganic–organic hybrid nano-adsorbent was prepared by chemical immobilisation of an organic Schiff base Cu (II) ion receptor, DHB ((E)-N-(1-(2-hydroxy-6-methyl-4-oxo-4H-pyran-3-yl) ethylidene) benzohydrazide), a selective dehydroacetic acid-based chemosensor, onto a mesoporous silica support. In order to prepare the sorbent, the silylating agent was anchored onto the silica. During this procedure, 3-Chloropropyl trimethoxy silane (CPTS) was attached to the surface, increasing hydrophobicity. By immobilising DHB onto the CPTS platform, the silica surface was activated, and as a result the coordination chemistry of the Schiff base generated a hybrid adsorbent with the capability to rapidly sequestrate Cu (II) ions from wastewater, as an answer to combat growing Waste Electrical and Electronic Equipment (WEEE) contamination in water supplies, in the wake of a prolonged consumerism mentality and boom in cryptocurrency mining. The produced hybrid materials were characterised by FTIR, proximate and ultimate analysis, nitrogen physisorption, PXRD, SEM, and TEM. The parameters influencing the removal efficiency of the sorbent, including pH, initial metal ion concentration, contact time, and adsorbent dosage, were optimised to achieve enhanced removal efficiency. Under optimal conditions (pH 7.0, adsorbent dosage 3 mg, contact time of 70 min, and 25 °C), Cu (II) ions were quantitatively sequestered from the sample solution; 93.1% of Cu (II) was removed under these conditions. The adsorption was found to follow pseudo-second-order kinetics, and Langmuir model fitting affirmed the monolayer adsorption
Charge recombination in polythiophene: non-fullerene acceptor solar cells with IE offsets exceeding 1 eV
Full text linkIn organic solar cells the energetic landscape of the donor–acceptor heterojunction determines the efficiency of charge generation and charge recombination processes, and thereby the device performance. Here, we present a study on a series of 15 donor–acceptor bulk heterojunctions (BHJs) consisting of either the donor polymer poly(3-hexylthiophene) (P3HT) or poly[2,5-bis(3-tetradecylthiophen-2-yl)thieno[3,2-b]thiophene] (pBTTT-C14) and selected non-fullerene acceptors (NFAs), spanning a wide range of interfacial energetics. We demonstrate that the internal quantum efficiency (IQE) is limited by geminate and non-geminate recombination processes and, importantly, decreases with the energy difference between the donor's ionization energy (IE) and the acceptor's electron affinity (EA), in other words, the diagonal bandgap, specifically if less than 1 eV, regardless of the interfacial IE offset. The dependence of charge recombination on the diagonal bandgap can be explained in the framework of the energy gap law. Our results provide further insight into the importance and impact of interfacial energetics in donor:NFA blends with large IE offsets
Redefining Freedom: Community and Kinship among the Jamaican Maroons and Garifuna in the 17th and 18th centuries
Full text linkThis thesis examines the resistance and resilience of two Black communities in the Caribbean—the Jamaican Maroons and the Garifuna of St. Vincent—against British colonialism in the 17th and 18th centuries. Through a comparative analysis, the study explores how these communities leveraged their unique cultural, geographic, and social contexts to challenge colonial domination, assert autonomy and establish what this thesis coins as communal freedom.Drawing from archival research and oral traditions, this research highlights the strategies of resistance employed by these groups, including guerrilla warfare, negotiated treaties, and cultural preservation. It also interrogates the role of British colonial policies in shaping the trajectories of these communities and their struggles for survival and sovereignty.The study situates these historical narratives within broader discussions of Black resistance, identity, and postcolonial legacies. It argues that the resilience of the Jamaican Maroons and the Garifuna offers critical insights into the enduring impacts of colonialism and the ways in which marginalised groups navigate and resist systems of oppression.This thesis contributes to Caribbean history, colonial studies, and African diaspora scholarship by providing a nuanced understanding of the interplay between resistance and adaptation in the face of colonial violence and displacement
Risk Appetite and (Mis)Pricing
Full text linkThis paper reexamines the beta-return relation through the lens of time-varying risk aversion. We show that the security market line (SML) depends critically on the level of aggregate risk aversion. During periods of high risk aversion, the SML exhibits a positive slope and an intercept that is statistically indistinguishable from zero, with investor sentiment playing only a minor role. During periods of low risk aversion, the SML slope becomes negative and the intercept is significantly positive. Investor sentiment affects the SML only when risk aversion is low. These patterns are robust across alternative portfolio constructions, longer investment horizons, and multiple measures of risk aversion
Pre-Arrival Confidence and Perceived Importance in First-Year UK Sport Students: A Multi-Institutional Examination of Gender, Institution and Programme Differences
Full text linkThis multi-institutional study examined pre-arrival confidence and perceived importance among first-year sport students across three post-92 universities and one public research university exploring programme of study, gender, and institutional differences, while also evaluating the psychometric properties of the pre-arrival survey. Of 1033 eligible students, 604 (58%) completed the survey across 25 sport-related programmes grouped into six categories: physiotherapy and rehabilitation, sport and exercise science, sports exercise and nutrition, sports coaching, sports management, and sport foundation year. Psychometric validation of the pre-arrival survey demonstrates its reliability and validity, providing the sector with a robust, standardised tool for assessing incoming students’ preparedness. Significant programme differences include physiotherapy and rehabilitation students reporting higher learning confidence, learning importance, and community confidence compared to other programmes. Female students demonstrated significantly higher learning importance and health and well-being importance than male students, though no gender differences in confidence were observed. Institutional variation was minimal, with one institution showing higher learning importance. Socioeconomic indicators did not significantly influence pre-arrival responses. The findings highlight the need for differentiated pre-arrival support targeting programme-specific confidence gaps and gender-related differences in perceived importance. The validated PAS provides a reliable tool for early identification of students requiring enhanced transitional support, potentially addressing persistent retention and progression challenges in UK sport programmes
Attitudes to earlier advance care planning: a qualitative interview study in general practice
Full text linkBackground Advance care planning (ACP) research has often focused on those experiencing deteriorating health. There is limited research regarding attitudes to early ACP among people living with long-term conditions without advanced illness or severe frailty.Aim To explore how people living with a non-cancer long-term condition understand ACP; and their preferences for how, if at all, these discussions should be undertaken, including within annual health reviews.Design and setting Qualitative interviews undertaken with participants from general practices in village, market town, coastal town, and city settings within England, UK.Method The interviews were semi-structured and in depth. The inclusion criteria were: >18 years old; registered at a participating practice; living with cardiovascular disease, diabetes mellitus, kidney disease, or chronic obstructive pulmonary disease. Thematic analysis used a critical realist approach. Participants contributed to a member checking process. This study had NHS ethics approval (23/PR/0078).Results In total, 21 participants were recruited who were aged 61–91 years, eight were men, and 17 participants were living with multimorbidity. Participants discussed three forms of ACP: proactive planning, preparing for change, and discussing the end of life. Participants described early ACP as less distressing. Participants perceived ACP as an ongoing process, with early consultations encouraging discussion of existing preferences and preparing people for future decision making. Participants discussed how ACP could facilitate proactive and person-centred health care. Participants described the importance of normalising ACP.Conclusion This study suggests that ACP may be well received and could be discussed earlier with adults living with long-term conditions, before onset of advanced illness or severe frailty
Cardiovascular risk profile of low-dose prednisolone and its effect on the quality of life in patients with adrenal insufficiency: the HYPER-AID observational study
Full text linkBackground: Patients with adrenal insufficiency require glucocorticoid replacement therapy either as hydrocortisone in multiple-daily doses or as low-dose prednisolone once daily. Data on the long-term safety, cardiovascular risk, and quality-of-life (QoL) outcomes of prednisolone remain limited. Methods: In this prospective longitudinal cohort study, patients with adrenal insufficiency underwent a pre-specified switch from multiple-daily dose hydrocortisone to once-daily low-dose prednisolone (2–4 mg) as part of routine clinical care and followed up for at least four months. Cardiovascular risk was assessed using anthropometric and biochemical markers (lipid profile, HbA1c, C-reactive protein, blood pressure, and waist and hip circumference). QoL was evaluated using a modified SF-36 questionnaire. Baseline and follow-up measures were compared using paired t-tests or non-parametric equivalents. Results: Of the 62 enrolled patients, 48 completed follow-up. The mean age was 54.5 ± 13 years; 56% were female; and 83% had secondary adrenal insufficiency. After at least four months on prednisolone, weight decreased significantly (90.6–89.6 kg, P = 0.007), accompanied by a reduction in systolic blood pressure (‒5 mmHg, P = 0.032). Lipid parameters, HbA1c, and CRP remained unchanged (P > 0.05). Energy scores improved significantly (+9 points, P = 0.003), and patients reported increased treatment convenience (P = 0.002). Conclusion: Low-dose once-daily prednisolone offers comparable cardiovascular risk to hydrocortisone while improving treatment convenience, systolic blood pressure, and SF-36 subjective energy scores. These findings support the use of prednisolone as a potentially preferable alternative in patients with adrenal insufficiency