Open Research Exeter - University of Exeter
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Threat-related Mental Imagery Reduces Endogenous Pain Modulation in Healthy Individuals
No full textMental imagery-based simulations of threat can evoke “as-if-real” emotional and motivational responses, which may alter top-down pain processing. This study investigated the impact of mental imagery simulations of threat on endogenous pain modulation in n = 71 healthy participants using a cuff-pressure algometry protocol. In block one, participants were assessed on their baseline pain detection threshold (PDT), pressure pain tolerance (PTT), and their conditioned pain modulation (CPM) responses. In the second block, participants underwent the same procedures again but were randomly allocated to imagine the dominant leg cuff as being made of bubble-wrap (benign imagery condition; n = 36) or metal wire (threat imagery condition; n = 35). In between blocks, participants went to a separate room to interact with a piece of real bubble wrap or metal wire around their legs, facilitating mental imagery generation in Block 2. Partially consistent with our hypothesis, mental imagery impacted CPM effects for pain detection threshold (PDT), which was significantly reduced in the Wire relative to the Bubble-wrap condition. Mental imagery did not influence pressure pain tolerance (PPT). These results indicate that mental simulations of threat may reduce threshold-based conditioned pain modulation (CPM) responses in healthy individuals. Present findings suggest that mental simulation of threat may influence endogenous pain modulation processes.</p
Reporting completeness of systematic reviews of nutrition or diet-related randomised controlled trials: A meta-research on adherence to PRISMA items
No full textAdherence to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) 2020 statement has not been explored in the nutrition field. The objectives of this meta-research were to assess the reporting completeness of systematic reviews with meta-analysis (SRs-MA) of nutrition- and diet-related randomized controlled trials (RCTs), and to identify their main reporting limitations, and potential factors associated with adherence to PRISMA. We analyzed a random sample of 100 SRs-MA of nutrition- and diet-related RCTs published in journals indexed on PubMed between July 2021 and July 2022. Pairs of reviewers read the full texts to independently extract the data. One reviewer collected data on the journal's endorsement of PRISMA guidelines. A reporting completeness (RC) score was created using the data from the evaluations regarding whether each fragmented item of PRISMA 2020, PRISMA 2020 Abstracts, PRISMA-Search, and TIDieR checklists (a total of 114 sub-items) was reported in the SRs-MA and compared the RCs between studies grouped according to predefined characteristics. SRs were published in 63 different journals; most (54%) endorsed the PRISMA guidelines. Most SRs-MA (86%) mentioned the PRISMA, and 21 attached the PRISMA checklist. The mean (±SD) RC score was 53.2 ± 7.1%. None of the PRISMA items were completely reported in all SRs-MA. Only 13 items were completely reported in more than 75% of the SRs-MA. Protocol registration (beta = 3.61; 95% CI 1.22-5.99), self-reporting of PRISMA adherence (beta = 4.21; 95% CI 0.72-7.70), and evaluation of the certainty of the body of evidence (beta = 4.99; 95% CI = 2.42-7.55) were associated with RC. The poor RC in SRs-MA of nutrition- and diet-related interventions demonstrates that research in this field requires improvements. Indicators of research integrity and transparency, such as protocol registration, self-reported adherence to PRISMA, and evaluation of the certainty of the body of evidence, were positively associated with RC.</p
The Past and Present of Maldivian Coral Reefs
No full textCoral reefs are highly diverse, valuable, but fragile ecosystems that are experiencing unprecedented degradation from anthropogenic impacts and climate change. Degraded reefs provide poorer ecosystem services, including reduced shoreline protection and diminished livelihoods through declining reef fisheries and tourism. Maldives is a coral reef-generated nation, putting it at great risk of climate change-associated damage, namely coral mortality from warming ocean temperatures and reef drowning from rising sea levels. In this thesis, I explore the past and present of Maldivian reefs using a combination of historical research, database searches, and field investigations to ask questions about national trends in coral reef condition, resilience, and the viability of restoration efforts. The research spans three global mass bleaching events that affected Maldives in 1998, 2016, and 2024. In Chapter 1, I conducted a broad-scale, comprehensive literature review to identify research relating to Maldivian coral reefs, which revealed 590 studies published between 1832 and 2022. A topic analysis of two centuries of change in research interests reflected changing relations between people and planet, from early studies focused on discovery and description to exploitation and impact in the early to late-20th century, and then moving on to how people are reshaping the world in the 21st century. In Chapter 2, I compiled all available quantitative surveys of Maldivian reefs to estimate temporal and spatial changes in coral cover through the Anthropocene. I analysed 1023 reef surveys conducted between 1957 and 2025 to show that mass coral bleaching events caused a 90.2% loss of coral in 1998, 60.6% in 2016, and 27.7% in 2024. Given broadly comparable levels of thermal stress between events, there appears to be growing reef thermal resilience across Maldives. In Chapter 3, I undertook field surveys to measure the size structure of coral colonies across Laamu Atoll, a southern atoll in Maldives. To better understand reef replenishment and recovery from the 2016 mass bleaching, I assessed small colony density as an indicator of coral recruitment. Coral recruit densities were high throughout the atoll and across all reef zones. Comparison with recruit density estimates from similar studies in other parts of the world indicates vigorous coral replenishment, which suggests Laamu Atoll’s coral reefs remain resilient. Finally, in Chapter 4, I provide the first insight into the impact of the 2024 coral bleaching event on three islands in Maldives and compare the differences in response to heat stress between restored reefs and adjacent natural reef counterparts. In assessing bleaching resistance and resilience within and among species, I show that restored and natural reefs exhibited similar levels of bleaching during the event and moderate but encouraging levels of partial and full colony recovery immediately after it. Overall, this thesis demonstrates that Maldivian coral cover has declined over time due to a series of severe marine heatwaves and intensifying anthropogenic pressures. Despite this, it also reveals increased thermal resilience in coral reefs, demonstrated by less coral mortality with each successive coral bleaching event, promising levels of full and partial colony recovery, and strong evidence of natural replenishment. While mitigating the effects of climate change remains essential for coral reef persistence, identifying the location of more resilient reefs and individual coral colonies could help make restoration efforts more targeted and effective.</p
Random Vibrations of Wind Turbines Mitigated by the Hourglass Transition Piece
No full textWind turbines are subjected to complex stochastic loadings generated by various environmental sources, including wind, waves, and earthquakes. Efficient mitigation of the resulting vibrations in the structural components, such as the tower and monopile, leads to more cost-effective designs and longer operational life by reducing fatigue accumulation. Conventional vibration control systems have primarily relied on tuned mass dampers. However, alternative and non-conflicting strategies that modify the connection between the tower and the foundation at the transition piece level have recently gained attention. This study investigates the hourglass transition piece (HGTP), a novel concept that utilises the Reduced Column Section approach. The hourglass geometry enables fine-tuning of the wind turbine’s fundamental period and introduces controlled rotational motion, both contributing to a reduction in structural stresses and improved dynamic performance. To assess the efficacy of the HGTP as a vibration control system, an analytical model of a simplified wind turbine is developed. The formulation employs frequency-dependent solutions of prismatic and tapered beam elements, assembled to capture the dynamic behaviour of the turbine equipped with the HGTP. Exact dynamic stiffness matrices are derived and assembled into a stochastic framework suitable for uniformly modulated non-stationary random processes. Modal and dynamic responses are evaluated for different reductions of the hourglass central section. A case study based on the IEA 15 MW Reference Wind Turbine demonstrates that the HGTP can mitigate stochastic mean peak bending moments induced by wind and earthquake excitations by up to 50%, confirming its potential as an effective vibration control solution.</p
Longitudinal associations between play experiences and trajectories of preschoolers’ mental health from April – July, 2020
No full textBackgroundPlay provides an important foundation for a healthy childhood but longitudinal data exploring how play experiences relate to children's mental health over time is scarce. In this study, data on preschool-aged children's activities and mental health during Covid-19 related restrictions was used to explore how where (inside/outside) and with whom children played related to internalising and externalising problems over time.MethodsUK based parents/carers (n = 1028) of preschool-aged children (2–5 years) completed an online survey at four time points between April and July 2020. The survey asked how much time in the previous week their child had spent: Playing inside; Playing outside; Playing alone; Playing with a parent; Playing with another child in their household; and their child's mental health (Strengths and Difficulties Questionnaire internalising and externalising scales). Four hierarchical linear regression analyses were conducted to examine associations between where children play (inside/outside) and (1) internalising and (2) externalising symptoms, and with whom children play (with parent, other child, alone) and (3) internalising and (4) externalising symptoms. Effects of linear and quadratic time, and interactions between play and time were examined. Parent mental health, parent education, contact with nature and physical activity were included as covariates.ResultsBoth inside and outside play was associated with less severe internalising problems (beta = −0.23 [SE = 0.10]; beta −0.54 [SE = 0.19]) and, in statistical interaction with time, less time playing inside was associated with a stronger improvement in externalising problems over time (beta = 0.77 [SE = 0.23]). Further, more time playing with other children was associated with less severe internalising problems (beta = −0.50 [SE = 0.13]) whereas playing alone was associated with more severe internalising problems (beta = 0.28 [SE = 0.10]).ConclusionVaried play opportunities are related to young children's mental health. Even during a pandemic response, children should be given opportunity to play with other children and play outdoors wherever possible.Key PointsWhat's known?Cross-sectional research suggests there is a relationship between play and mental health in children.It is unclear how the specific context of children's play affects associations with mental health.What's new?For internalising problems, inside and outside play, and more time playing with other children were associated with fewer symptoms. More time playing alone was associated with more symptoms.For externalising problems, no main effects of play were found but symptom levels remained relatively stable over time for children who spent more time playing inside, whereas children who spent less time playing inside had a decreasing symptom trajectory over time. Time spent playing with parents was not significantly associated with preschoolers' mental health.What's relevant?Understanding how children's play activities can be used to improve their mental health during periods of enforced isolation is essential to inform the development of future policies and guidance.</p
CityVerse: A Unified Data Framework for Evaluating Large Language Models in Urban Computing
No full textLarge Language Models (LLMs) show remarkable potential for urban computing, from spatial reasoning to predictive analytics. However, evaluating LLMs across diverse urban tasks faces two critical challenges: lack of unified platforms for consistent multi-source data access, and fragmented task definitions that hinder fair comparison. To address these challenges, we present CityVerse, the first unified platform integrating multi-source urban data, capability-based task taxonomy, and dynamic simulation for systematic LLM evaluation in urban contexts. CityVerse provides: (i) coordinate-based Data APIs unifying ten categories of urban data—including spatial features, temporal dynamics, demographics, and multi-modal imagery-with over 38 million curated records; (ii) Task APIs organizing 43 urban computing tasks into a four-level cognitive hierarchy: Perception, Spatial Understanding, Reasoning & Prediction, and Decision & Interaction, enabling standardized evaluation across capability levels; (iii) an interactive visualization frontend supporting real-time data retrieval, multi-layer display, and simulation replay for intuitive exploration and validation. We validate the platform’s effectiveness through evaluations on mainstream LLMs across representative tasks, demonstrating its capability to support reproducible and systematic assessment. CityVerse provides a reusable foundation for advancing LLMs and multi-task approaches in the urban computing domain. The framework is publicly available at https://julietjobs.github.io/City_Verse/.</p
Fine-scale proximity to offshore wind turbine foundations increases biomass of demersal fish species
No full textOffshore wind turbine fixed-bottom foundations provide artificial hard substrate through the water column that encourages marine flora and fauna to colonise and aggregate around the introduced structures, a well-documented phenomenon known as the ‘artificial reef effect’. The cumulative impact thousands of turbine foundations at multiple offshore sites have on local and regional marine species populations and communities is not fully understood. Knowledge of the extent and magnitude of the reefing effect at a fine scale (single turbines) is a prerequisite to making broader-scale (single or multiple wind farms) predictions of population level and ecosystem changes caused by presence of offshore wind farms. The influence of fine-scale distance (<250 m) to turbine jacket foundations on abundance, biomass and size of demersal fishes was assessed at a northern latitude wind farm. Abundance and biomass of all demersal fishes, flatfish Pleuronectiformes spp. and haddock
Melanogrammus aeglefinus
were found to have a significant negative relationship with increasing distance from foundations. Haddock were found to aggregate closer to the structures, yet all statistical models predicted a similar magnitude of increase for each group of between ~1.5 and 1.6 times more individuals and biomass at 30 m from the foundations compared to 240 m. The results illustrate that fine-scale proximity to offshore wind fixed foundations has considerable effects on the presence of some demersal fish species. The cumulative or wider ecosystem consequences of these effects are not known, but the further evidence for localised reefing effects can be of strategic interest for optimizing future wind farm project design, included implementation of nature-inclusive measures that could help meet future marine net gain aspirations.</p
Road network generation from noisy trajectories with graph latent diffusion models
No full textModern navigation systems and logistics services rely heavily on digital road networks, which can be accurately constructed from crowd-sourced GPS trajectories. Yet, most existing trajectory-based road network generators project GPS coordinates to 2D grid, followed by semantic segmentation to obtain road heatmap, and further processed to road network graph via heuristic processing. The data through this pipeline involve multiple cross-modal heuristic conversions, which cause serious information loss and harm overall robustness. In this paper, we propose a novel end-to-end learnable deep learning approach, named GraphWalker, to generate accurate road network graphs directly from raw trajectories with minimal information loss. In particular, GraphWalker is a latent diffusion model (LDM) consisting of two key components: the Trajectory-to-Walks Diffusion Transformer (T2W-DiT) generates walks with trajectories as conditions, and the Walks-to-Graph Variational Auto-Encoder (W2G-VAE) reconstructs road network graphs from walks. GraphWalker keeps the data in geographical space throughout the pipeline to retain all information within raw trajectories. Additionally, the end-to-end learnable design removes the heuristic processing and enhances the robustness and generalizability. Extensive experiments on multiple datasets demonstrate that the proposed GraphWalker can effectively generate high-quality road networks from noisy and sparse trajectories, showcasing significant improvements of up to 55.43% over state-of-the-art. </p
Pharmaceuticals in the Environment: Assessing Potential Risks to Fish
No full textThe widespread presence of human pharmaceuticals in aquatic ecosystems potentially poses a significant threat to vulnerable organisms, such as fish. To address this issue, the environmental risk assessment (ERA) of active pharmaceutical ingredients (APIs) is now integrated into various regulatory frameworks worldwide. However, the ERA process is often resource-intensive and furthermore raises ethical concerns over the use of experimental animals. Moreover, its effective implementation is hampered by limited understanding of organism-specific pharmacokinetics, including the absorption, distribution, metabolism and excretion of drugs. As a result, New Approach (non-animal) Methodologies (NAMs) are increasingly being explored and adopted. While these methodologies hold promise for addressing vital knowledge gaps, ongoing refinement and validation are essential to keep pace with technological advances and ensure robust protection of organismal and environmental health.
This thesis focuses on assessing fish as sensitive receptors of pharmaceutical pollutants in the aquatic environment, identifying key factors that influence organismal susceptibility, and evaluating a series of NAMs for their potential to enhance understanding of fish-specific pharmacokinetics and support a more targeted, refined ERA process.
The first phase of this work entailed a critical review of existing literature, which highlighted the fundamental role of species-specific pharmacokinetics in determining the susceptibility of fish to pharmaceutical exposure and effects. With metabolism being a key contributor in this regard, an in vitro rainbow trout (Oncorhynchus mykiss) primary hepatocyte monolayer culture system was applied to assess the hepatic clearance of five APIs with diverse physicochemistries and drug targets, namely propranolol (beta-blocker), quetiapine (antipsychotic), mycophenolic acid (MPA; immunosuppressant), clozapine (antipsychotic) and olaparib (antineoplastic). Inter-relationships between API exposure and drug clearance processes in trout hepatocytes were also investigated by quantifying selected gene transcripts and the activity of cytochrome P4501A – an important phase I drug-metabolising enzyme. In addition to affirming the hepatocyte monolayer culture system’s usefulness, the findings from this work underscore the importance of acknowledging organism-specific clearance capacities and pathways. The monolayer model was also critically evaluated against other in vitro liver models used to measure pharmaceutical clearance in fish, including subcellular fractions, hepatocyte suspensions and spheroids. This analysis demonstrated the strong utility and broad applicability of the various in vitro models, offering a complementary toolkit for refining pharmaceutical ERA and advancing understanding of fish hepatic physiology. In the next phase of work in this thesis, rainbow trout tissue samples were used to study tissue-specific bioconcentration of APIs, as well as changes in gene transcript levels and metabolic enzyme activity following in vivo exposures to three of the case-study APIs (quetiapine, MPA and olaparib). These studies revealed the complexity and heterogeneity of biological responses in whole organisms to chemical exposure and identified some distinct API clearance mechanisms between fish and humans. Measured API tissue concentrations from the in vivo studies were subsequently used to evaluate the predictive accuracy of a refined, generalised fish physiologically based kinetic (PBK) model. After incorporating species-specific physiological pH and in vitro-derived plasma protein binding data, however, the refined model demonstrated only marginal improvement over the original version. Consequently, further optimisation and validation of the model are warranted.
Taken together, and pending further optimisation, the tools explored in this thesis show promise as effective and ethically sound approaches for generating data to support pharmaceutical ERA and broader eco(toxico)logical research. In these contexts, their potential applications include prioritising APIs for further testing and improving understanding of species-specific risk, thereby reinforcing the growing relevance of NAMs.</p