Open Research Exeter - University of Exeter
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Biologging for marine megafauna conservation: animal tracking, environmental monitoring, and modelling approaches.
No full textMarine megafauna face ongoing threats from human activities, including fishing
pressure, habitat destruction, and climate change. Biologging—the use of
electronic tags to study animal movement, behaviour, physiology—has emerged
as a critical tool for understanding animal ecology and informing conservation
strategies. This thesis explores the application of state-of-the-art biologging
technologies to address major conservation challenges facing sharks and sea
turtles, two groups that have experienced severe population declines driven by
human activities.
Through five case studies, this research demonstrates the versatility of biologging
in tackling diverse conservation questions. Satellite tracking of leatherback turtles
(Dermochelys coriacea) in Equatorial Guinea revealed spatial mismatches
between existing marine protected areas and critical nesting habitat, supporting
recommendations for MPA expansion. Novel sound-recording tags deployed on
leatherback turtles in Gabon quantified pervasive anthropogenic noise pollution
in important nesting areas, highlighting an emerging threat requiring
management attention. Post-release survival analysis of three shark species in
UK recreational fisheries revealed high (>95%) survival rates, providing the first
European assessment of catch-and-release impacts and supporting current best-
practice guidelines. An agent-based model parameterized with pan-Atlantic
leatherback tracking data enabled simulation of complete remigration cycles,
extending insights beyond typical tag deployment periods and identifying
previously overlooked bycatch risk areas. Finally, computational fluid dynamics
modelling of tag drag on pelagic sharks revealed that tag placement significantly
outweighs tag mass in determining energetic costs, providing data-driven
guidelines for ethical tagging practices.
This research contributes to the growing integration of biologging and
conservation science, demonstrating how advances in animal tracking can
directly inform management decisions. The studies highlight persistent
challenges in the field, including the need for standardized analytical approaches,
improved data sharing protocols, and evidence-based tagging guidelines. As
marine ecosystems face increasing anthropogenic pressures, biologging will
remain essential for developing adaptive, data-driven conservation strategies for
marine megafauna.</p
Navigating the risks in epilepsy across the lifespan; narratives of adults with epilepsy
No full textAbstract
Objective: Epilepsy is generally considered to be a lifelong condition. Consequently, there is likely to be a diverse array of experiences in navigating epilepsy and the associated risks across the lifespan or shifts in perspectives as the person learns to adapt to living with epilepsy over time. It is important to learn about risk from the perspective of those navigating epilepsy risks daily. This study sought to understand the lived experience of epilepsy risk over time from the perspective of those living with the health condition.
Method: Eleven people took part in a narrative interview. Narrative analysis was used to identify story summaries, turning points that indicated a change in how epilepsy risk was managed and subject positioning.
Findings: Analysis of the eleven narratives revealed five story summaries, three turning points and four subject positions, that described a vast array of shared and individual experiences of managing the risks associated with epilepsy over time.
Conclusion: The findings demonstrated how entangled the experience of managing epilepsy risks are in people with epilepsy’s lives. Although some aspects of risk linked with developmental life stages, risk changes were fluid, complex and often an individual experience, entangled among personal, social and cultural contexts. It seems that the risks associated with epilepsy are vast and extend beyond the seizures, with many expressing that they felt there were unheard epilepsy risks, that impacted their personal situations. More research is needed to gather a better understanding of epilepsy risk in wider, diverse and individual contexts.</p
Mermaids and Sirens as Androgynous Figures in Victorian Art and Literature 1870-1915
No full textThrough the lens of queer, trans and feminist theory, this project explores the androgynous depictions of mermaids and sirens in Victorian art and literature. It focuses on three Pre-Raphaelite artists – Edward Burne-Jones (1833-1898), Evelyn De Morgan (1855-1919) and John William Waterhouse (1849-1917) – who produced prolific mermaid and siren output, alongside their literary and biographical influences. Several other Victorian artists such as Frederick Leighton and Herbert Draper depicted these creatures, but always as feminine ‘femme fatales’ – a trope upon which much scholarship already exists. These three second-wave Pre-Raphaelites, however, appear to do something different, perhaps initiating the development of the mermaid as the queer symbol recognised today. This thesis investigates why these artists chose to diverge from dichotomous Victorian gender norms in their works, and why the figures of mermaids and sirens were chosen as the vessels through which to do so.
This exploration is navigated within a framework of theoretical concepts such as Dustin Friedman’s queer Aestheticism, José Esteban Muñoz’s queer utopianism, Astrida Neimanis’s hydrofeminism and Susan Stryker’s trans monsters. These concepts, when reviewed together, present the idea that queer Aesthetic art looks towards an ideal future in which individuals are free to express a greater range of gender identities.
For each artist, this thesis assesses the extent to which biographical, societal, artistic and literary factors shaped their androgynous mermaid and siren artworks. Their enduring legacy and impact today, both on the art world and on our attitudes to gender, is considered in light of the project’s findings.</p
Source Data for "Amygdala GABA Neurons: Gatekeepers of Stress and Reproduction in Female Mice"
No full textSource Data to reproduce the figures for manuscript:Amygdala GABA Neurons: Gatekeepers of Stress and Reproduction in Female MiceAbstractStress can disrupt menstrual cycles, impair fertility and cause reproductive disfunction. The posterodorsal medial amygdala (MePD) integrates stress signals and regulates the gonadotropin-releasing hormone (GnRH) pulse generator through a dense network of GABA and Urocortin-3 (UCN3) neurons, yet the mechanisms underlying the circuitry remain poorly understood. Here, we combine in vivo mini-endoscopic calcium imaging, optogenetics, clustering analysis, and computational modeling to investigate the MePD circuitry. We uncover two anti-correlated GABA subpopulations in the MePD that are involved in the response to restraint stress and UCN3 neuron stimulation. Computational modeling suggests that mutual inhibition between these GABA groups drives their anti-correlated activity and predicts how these interactions shape downstream responses to stimulation of GABA and UCN3 neurons. In vivo optogenetics confirms that GABA neurons are critical for transmitting UCN3 signals to regulate luteinizing hormone (LH) pulse frequency. Together, our findings reveal amygdala GABAergic circuit mechanisms that mediate stress effects on reproductive health, linking emotional processing and neuroendocrine control.The manuscript is accepted for publication, currently deposited to https://www.biorxiv.org/content/10.1101/2025.01.06.631361v4The code for data analysis and computational modelling carried out in the manuscript is available in ORE: https://doi.org/10.24378/exe.31018072</p
Digital Twin for Machine Tools and Manufacturing Systems
No full textThis doctoral research develops an integrated Digital Twin (DT) and Cyber-
Physical System (CPS) framework for machine tools and manufacturing systems,
addressing the challenges of model fidelity, knowledge extraction and cost-
effective deployment in industrial environments. The study makes three key
contributions. Firstly, it proposes a lightweight hybrid modelling approach that
fuses finite element analysis with neural networks to predict multi-physics
behaviours of machine components. Secondly, it presents a semantic text-
analysis pipeline that transforms unstructured maintenance logs into interpretable
fault categories. Thirdly, it designs and validates an edge-deployable predictive
maintenance system that achieves real-time performance under stringent
resource constraints.
The framework is evaluated through three experimental cases. The first one is a
virtual–physical dynamic modelling case for rotating shafts using FEM and NARX
networks. The second one is an industrial text-mining case involving over 2000
lines of historical fault records from an automotive connecting-rod production line.
And the third one is an edge-intelligence prototype for gearbox monitoring built
on low-cost micro-controllers. Across the three cases, the results demonstrate
high-fidelity dynamic prediction (error <5%), robust unsupervised fault clustering
(silhouette score up to 0.9), and fast real-time response for edge sensing and
actuation (0.3 s latency with 62% improvement over a PID baseline).
5
The digital twin that is developed and analysed in this research is an outcome of
and extensive cycles of process that includes design, simulation and feedback-
based refinement, the virtual model collaborates with its real-world counterpart
for increased fidelity and robustness. Furthermore, the proposed DT framework
enables a scalable deployment of its components from sensor-level data
acquisition to higher-level of platform services in an incremental, stepwise
manner of theoretical integration and methodology over specific quantitative
analysis. In summary, the dissertation provides a formal and conceptually
grounded overview of how integrating digital twins within CPS architectures,
paired with an iterative development methodology, can advance intelligent
manufacturing. However, several limitations remain, including the lack of
thermal–mechanical coupling in the DT models, the reliance on enterprise-
specific datasets for text analysis and the limited generalisability of the current
edge prototype. These constraints offer clear opportunities for future work in
multi-physics fusion, cross-factory validation, and scalable cloud–edge intergrations.</p
Evolution of aquatic snails’ defences resulted in clade-specific differences in egg toxicity, pigments, and warning colouration
No full textOviparous animals have evolved diverse strategies that deter egg predation. In terrestrial species, these often include noxious compounds and aposematic signalling, but little is known in freshwater environments. Here we unravel the evolutionary and ecological strategies of Pomacea, aquatic snails that lay conspicuous masses of toxic orange-pink eggs to reduce predation risk. We reveal the interplay among warning colouration, toxicity, and predator visual perception that enables the evolution of advanced chemical defences. We provide evidence that snails modify dietary carotenoids and that this controls egg colouration in a clade-specific manner. Snails from the canaliculata clade accumulate more and brighter-coloured egg carotenoid pigments than those from the bridgesii clade. The conspicuousness of colour signals was assessed using field data, spectral reflectance measurements, and visual modelling. We show that aposematic signal variation among species is likely noticeable to putative waterbird predators. Feeding egg extracts to birds adversely affected their gut morphology. Comparative analysis revealed a correlation among pigment modification, conspicuousness, and toxicity, demonstrating that colour acts as an honest aposematic signal in apple snail eggs. To our knowledge, our study provides the first example of an honest aposematic signal in warning colouration among freshwater invertebrates.</p
Studies of Novel 2D Materials Based Devices and their Encapsulation
No full textTwo dimensional (2D) materials, such as graphene and transition metal dichalcogenides (TMDs), are at the forefront of next generation electronic and optoelectronic technologies due to their atomic scale thickness, exceptional carrier mobility, and tuneable physical properties. Their applicability in flexible electronics, high speed transistors, sensors, and quantum devices is well established. However, their monolayer structure makes them highly sensitive to environmental interactions, including substrate effects and atmospheric doping, which can degrade device performance by introducing charge inhomogeneities and mechanical strain.
To address these challenges, this thesis investigates soy wax as a non-invasive encapsulation. Raman spectroscopy demonstrates that soy wax encapsulation significantly enhances the structural uniformity of graphene, narrowing and centring the distributions strain and doping. Strain levels stabilize around 0.5%, while doping concentrations converge near 0.20 × 10¹³ cm⁻². These findings indicate a reduced charge inhomogeneity and mechanical distortion, contributing to improved carrier mobility and a more stable electronic environment.
In parallel, this thesis explores the structural characteristics of emerging 2D TMDs such as ReS₂, WTe₂, and In₂Se₃ which hold significant potential for nanoelectronics and optoelectronic applications. ReS₂ exhibits in-plane anisotropy, WTe₂ shows topological and magneto-resistive behaviour, and In₂Se₃ possesses intrinsic ferroelectricity. Raman spectroscopy enabled precise estimation of the number layers through characteristic vibrational modes, while atomic force microscopy (AFM) provided detailed measurements of surface roughness and step heights, confirming thickness and uniformity. Together, these complementary techniques enabled a thorough assessment of material quality, which is crucial for reliable device integration. Overall, the findings underscore the importance of encapsulation strategies and high resolution structural characterization in enhancing the performance and scalability of graphene and other 2D materials for advanced electronic applications.</p
Online action-stacking improves reinforcement learning performance for air traffic control
No full textWe introduce online action-stacking, an inference-time wrapper for reinforcement learning policies that produces realistic air traffic control commands while allowing training on a much smaller discrete action space. Policies are trained with simple incremental heading or level adjustments, together with an action-damping penalty that reduces instruction frequency and leads agents to issue commands in short bursts. At inference, online action-stacking compiles these bursts of primitive actions into domain-appropriate compound clearances. Using Proximal Policy Optimisation and the BluebirdDT digital twin platform, we train agents to navigate aircraft along lateral routes, manage climb and descent to target flight levels, and perform two-aircraft collision avoidance under a minimum separation constraint. In our lateral navigation experiments, action stacking greatly reduces the number of issued instructions relative to a damped baseline and achieves comparable performance to a policy trained with a 37-dimensional action space, despite operating with only five actions. These results indicate that online action-stacking helps bridge a key gap between standard reinforcement learning formulations and operational ATC requirements, and provides a simple mechanism for scaling to more complex control scenarios.</p
Learning Capacity in International Organizations: The Case of the World Health Organization
No full textThis chapter summarises some of what we know about learning in international organizations (IOs). Drawing on organizational studies, public policy and administration and international relations (IR) literatures on learning, we focus on one IO – the World Health Organization (WHO) – to showcase what conditions learning capacity in IOs.
Why view IOs and their capacities through a learning lens? IOs aim to foster cooperation on some of the most complex policy challenges of our age. Success is far from guaranteed and indeed remains elusive on many existential threats. Yet, the post-war architecture of IOs grows and many of them have proved capable of brokering compromise in complex power constellations, navigating knowledge politics to build consensus and developing institutions which reform. In short, IOs need to learn and many of them do.
The chapter is structured as follows. To start, we outline definitions of organizational learning and the forms it takes. We then introduce the WHO as an IO with substantial potential for learning capacity. The main part of the chapter addresses three factors which we know shape organizational learning dynamics: power relations around an IO (particularly its interactions with member states), the status of experts and, finally, the IO’s own organizational design and leadership. Respectively, these mediate the possibilities for building compromise, consensual knowledge, and convening spaces for collective reflection. Throughout, we use empirical examples from global public health challenges to illustrate these dynamics at work in the WHO, how learning capacity delivers and its limitations.</p
Discrete event simulation for sustainable hospital pharmacy: the case of aseptic service unit
No full textWithin hospital pharmacies, aseptic units preparing high-risk injectable medicines face environmental and economic challenges due to high resource consumption and carbon emissions. Variability in patient dosage requirements leads to inefficient drug vial usage, resulting in waste generation, carbon emissions generation from waste, and increased costs. Batching could be used to reduce resource consumption and reduce waste associated with single-dose preparation. This study develops a discrete event simulation (DES) model, as a tool for strategy evaluation and experimentation, to assess the impact of batching on productivity and sustainability. The model captures key process dynamics, including prescriptions arrivals, production processes, batching strategies, and resource consumed (e.g. vials, consumables). By experimenting with time-sensitive and size-based batching, the study evaluates their effects on the reduction of medical and nonmedical waste, thereby contributing to cost savings, reduction of carbon emissions, and productivity by enhancing workflow efficiency and optimizing resource utilization. This study offers valuable insights for hospital pharmacies to evaluate the effectiveness of batching strategies for reducing waste and promoting sustainability.</p