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This thesis focuses on how food provisioning platforms are understood and appropriated in everyday life. Taking food provisioning as social practice, it explores how platforms help organise everyday food and non-food practices, and whether they have the potential to reconfigure food consumption. This exploration is important for contemporary food-related social and environmental issues because although platforms are claimed to offer opportunities for more sustainable food consumption, they risk entrenching existing patterns of food consumption and exacerbating the problems. This study examined three types of food provisioning platforms in Bristol, UK, namely takeaway delivery, online grocery, and box schemes. Drawing on social practice theory, Science and Technology Studies, and Actor Network Theory, it employs a range of methods, including mapping platforms and their representations, food diaries, 23 semi-structured interviews (with kitchen demonstration) and observations (with digital walkthroughs), to examine the organisation and performance of platform-based food consumption. Attention is paid to the appropriation of platforms in everyday life, mainly from three perspectives: the organisation of everyday food and non-food practices, the material arrangements where food practices transpire, and consumers’ interactions with platform technologies. Data analysis reveals that although convenience is generally presented as the reason for using food provisioning platforms, people actually use platforms to coordinate food provisioning practices and other food and non-food practices, in temporal and material dimensions. First, consumers use platforms to reallocate, synchronise, sequence and ‘rhythmise’ food practices (food planning, purchasing, storing, cooking, eating and waste managing) and other non-food practices (working, commuting, and childcaring). Second, heterogeneous material elements within and beyond the household (including food, digital de

This thesis develops functional reduction into a full account of inter-theory reduction in the physical sciences. Functional reduction characterises inter-theory reduction as the recovery of the higher-level behaviour described by the reduced theory in terms of the lower-level reducing theory. For example, finding a statistical mechanical realiser that can play the role of thermodynamic entropy establishes a reductive link between thermodynamics and statistical mechanics, as thermodynamic behaviour can be recovered from statistical mechanics. This account constitutes an original method of reduction offering numerous advantages and has been applied in various domains in the physical sciences. However, for functional reduction to be a full account of theory reduction, we need to specify how theoretical elements and ontology are related within the view, how functional roles are formulated, and how the account is related to other approaches to reduction. We tackle these questions by advancing two alternative frameworks for functional reduction, namely `Syntactic Functional Reduction' and `Semantic Functional Reduction'. They elaborate on functional reduction in different ways. The former expands upon David Lewis' account, employs a logical characterisation of functional roles, and is combined with Nagelian reduction. The latter spells out functional roles mainly in terms of mathematical roles within models and builds on the mathematical approach to reduction. Hence we argue that functional reduction can embed both Nagelian and mathematical reduction and improve on them. We apply these two frameworks to some detailed case studies from physics, to study their implications and improve our understanding of those case studies. Moreover, we apply functional reduction outside of physics, to biochemical entities. Overall, this thesis advances our understanding of functional reduction in science and provides an ideal platform for further applications of the approach.

The study and development of automotive suspension is an active research topic. It is well-known that improving the ride comfort comes at the cost of vehicle handling. To solve this, active suspension systems have been suggested, developed, and implemented by industry and academia. However, with the introduction of the inerter, the ability to solve this trade-off passively has improved. This thesis studies the extent to which inertance-integrated absorbers improve the performance of two different vehicles: a linearised five-mass model of an in-wheel motor powered vehicle, and a full car model with air springs. The findings of this thesis provide a step towards the adoption of inertance-integrated suspension systems by the automotive industry. Firstly, a five-mass model of an in-wheel motor powered vehicle is modelled in MATLAB and Simulink. By incorporating and optimising inertance-integrated absorbers into the strut and bushes, the performance metrics for the vehicle (ride comfort, tyre dynamic load, and magnetic gap deformation between the rotor and stator) are improved without degrading the others. This study is the first to incorporate inertance-integrated absorbers in an in-wheel motor system, and shows the performance benefit they provide exceeds that possible with passive dampers without needing active control. Next, MATLAB and Simulink are used to model air springs consisting of air bags connected via pipes to reservoirs. These air springs replace the coil springs of a passenger car modelled in CarMaker. A pneumatic network design methodology is devised and used to perform pneumatic network synthesis on the pipes. This pneumatic network design methodology allows optimal linear inertance-integrated pneumatic networks to be found and completes the existing mechanical-electrical-hydraulic domain coupling methodologies, which previously did not consider pneumatic networks. Real-time simulations are performed with MATLAB, Simulink, and CarMaker

Background: Relatively little is known about antibiotic use (ABU) on smallholdings in the UK compared to commercial farming. Due to differences in outlook, goals and farming methods, ABU practices and recommendations to improve antibiotic stewardship are likely to be different. I sought to explore facilitators and barriers to appropriate ABU on UK smallholdings to derive recommendations for improving antibiotic stewardship among this group. Methods: I used Participatory Epidemiology-inspired approaches to explore networks, structures and practices around ABU on smallholdings. This included a content analysis of smallholding print media; smallholding farm walks, ranking exercises – including Q method – and timelines; and semi-structured interviews with veterinarians. Results: Facilitators to appropriate ABU discussed by smallholders and veterinarians included perceptions of ABU on smallholdings being low in comparison to commercial farms. Single animal treatments were seen to be the mainstay of ABU and smallholders aimed to avoid unnecessary ABU. Identified barriers to appropriate ABU included difficulties diagnosing the cause of clinical signs of disease, which often led to a first-line approach of ABU. Consideration of the most likely cause of clinical signs of disease – in terms of bacterial species – rarely appeared to determine the type of antibiotic used and antibiotics were frequently employed to prevent future infections. Further, ABU which was not supervised by a veterinarian appeared common. Reasons for non-veterinary-supervised ABU included fractures in the smallholder-veterinarian relationship, the cost of veterinary visits and a perceived slowness in receiving veterinary advice. Conclusion: By considering these results, I have been able to suggest recommendations aimed at improving antibiotic stewardship. These include supporting veterinarians to undertake a logical thinking process for antibiotic-related decisions, thereby facilita

Quantum technologies, if fully realised, will outperform classical methods for a restricted but potentially revolutionary problem set. This promise has spawned a vast industry and research efforts around the globe, with a variety of different hardware platforms advancing at breakneck speed. In this work, we will focus on integrated quantum photonics - the effort to generate, manipulate and detect light in chip-scale devices. While this platform is the most natively scalable, enormous advances are required in order to reach a utility scale machine. Perhaps the most pressing is that of fully integrated feedforward - the process of measuring part of a quantum state and updating an operation on a subsequent part of the state based on the outcome. This process is critical for any photonics architecture, and requires the coordination of photonics, electronics, and cryogenics. In this thesis we attempt to develop a scaleable architecture for this process in a novel photonic platform - silicon in the mid-infrared. In Chapters 1 and 2, we make the case for this platform and show advances in sources, modulators and detectors. The work in Chapter 3 shows a basic systems-level experiment in the platform - a violation of the CHSH inequality, demonstrating mid-infrared entanglement on-chip. Chapter 4 discusses the integration of detector arrays, and gives an architecture for an integrated feedforward experiment. We finish in Chapter 5 with both a brief retrospective and prospective.

Chapter 1 details the use of fluorine in organic chemistry and specifically its applications in pharmaceuticals. Fluorinated compounds have broad pharmaceutical applications, where fluorine incorporation can affect the ADME profile of drug compounds. Introducing functional groups into an alkyl chain in a 1,3-relationship can effect conformational control; specifically, 1,3-difluoro motifs can enable complementary control compared to the more common 1,2-difluoro (vicinal) motifs. Both geminal and vicinal difluorination have been achieved using alkenes as starting materials, but the analogous 1,3-difluorination remains elusive. Chapter 2 details synthetic routes towards alkyl fluorides, including a focus on hypervalent iodine reagents and their application to alkene fluorinations. The development of the 1,3-difluorination of homoallyl ethers using a commercially available hypervalent iodine reagent is discussed. The transformation is demonstrated on (hetero)aryl, benzylic, and alkyl ethers bearing a homoallyl alkene and showing tolerance to homoallyl chain substitution. This provides a route towards the rare 1,3-difluoro moiety from readily available alkene starting materials, facilitating alkane backbone diversification and conformational control. The synthesis and reactivity of high-valent nickel and palladium complexes are discussed in Chapter 3, including synthetic routes towards aryl fluorides. An in-depth study into the current state-of-the-art in direct aryl C-H fluorination using high-valent metal fluoride complexes is discussed, as well as attempts to translate the methodology using nucleophilic sources of fluoride to provide a cheaper and more atom-efficient route towards reactive reagents for fluorination. Additionally, this chapter details the design, synthesis, and characterisation of Pd(II/IV) and Ni(II/IV) complexes and their reactivity towards direct aryl C-H fluori

This thesis addresses the revolutionary role of an Egyptian playwright during times of socio-political flux. The key question is: to what extent do socio-politically engaged Egyptian plays mirror and contribute to historical moments characterised by revolutionary and political flux. After providing a critical survey of the history of Egyptian theatre, I analyse and contextualise plays by three Egyptian playwrights after which I subject those plays to six criteria I have composed. The playwrights are Tawfiq Al-Hakim (1898 – 1987), Nu’mān ‘Ashour (1918 – 1987) and Sa’ad Wahba (1925 – 1997). The theoretical framework of this thesis employs terms from Marxist-Leninist writings such as Party Organisation, Antonio Gramsci’s Hegemony and Raymond Williams’ Structures of Feeling. Since I contend that a revolutionary play should break the rules of Aristotle’s Poetics as understood by Egyptian scholars, I have used Rashad Rushdy’s translation of the Greek text. I also employ Egyptian founding documents, The National Charter (1962) and the six tenets of the 1952 Free Officers’ July movement. The conclusion of this thesis is that ‘Ashour and Wahba’s writings play a revolutionary role in the history of Egyptian dramaturgy while Al-Hakim, despite his contributions to the development of Egyptian theatre, has, in terms of dramaturgy, provided the Egyptian canon with texts that critiqued the socio-political order in a manner that Nasserists would view as counter-revolutionary.

This thesis contributes to the theory of estimation and inference of endogenous models with weak instruments. In Chapter 1, we discuss overidentification testing with weak instruments and heteroskedasticity. We derive limiting distributions of the J-test (Hansen, 1982) and the KP-test (Kleibergen & Paap, 2006), interpretable as 2SLS-based and LIML-based robust score tests respectively. This is the first application of the KP-test to overidentification testing. We find that KP typically outperforms J and can be considered a more reliable test under heteroskedastic weak instruments. Staiger and Stock (1997) suggest LIML-based inference in homoskedastic weak-instrument settings, and we recommend the same under heteroskedasticity. In Chapter 2, we apply the results of Chapter 1 to the macroeconomic problem of estimating the elasticity of intertemporal substitution (EIS) in consumption lifecycle models. We suggest that J frequently erroneously rejects the overidentifying restrictions, whereas KP does not suffer from this problem. This suggests that instrument invalidity is not a likely cause of the lack of consensus regarding estimates of sensible values of the EIS seen in the empirical macroeconomics literature. In Chapter 3, we develop a new characterisation of weak instruments in a nonparametric setting. With this characterisation, we derive rates of convergence of the Tikhonov-regularised and series truncation estimators, and derive the minimally impermissible rate of localisation - the instrument weakness bound for which estimators are not consistent. The degree to which instruments can be weak is dependent on the degree of ill-posedness and the smoothness of the structural function. With mildly weak instruments, researchers can still consistently estimate the structural function. We also find that series truncation is more robust to weak instruments than Tikhonov regularisation, in that the estimator is consistent in a wider range of models than Tikhonov when t

Bacteria, with their robust membranes, have evolved extensive resistance mechanisms to protect themselves against antibiotic actions. Acting as a critical barrier, the bacterial membrane plays a pivotal role in mediating the interactions between bacteria and antimicrobial agents. Understanding the membrane structure and function is crucial to addressing multi-drug resistant bacterial pathogens. Gram-negative bacteria have a thinner layer of peptidoglycan in their cell wall, which is surrounded by a highly asymmetric outer membrane containing 75% bacteria-specific lipopolysaccharides (LPS). The headgroup of LPS is abundant in phosphates carboxylates groups, making it anionic in nature. Gram-positive bacteria have a thick layer of peptidoglycan in their cell wall, with a polymer-like amphiphile called lipoteichoic acid (LTA) anchored to the phospholipid membrane. The polyglycerol-phosphate backbone of LTA carries significant negative charges due to the presence of the phosphate groups. This study has developed and characterized the membrane models incorporating key bacterial membrane components, i.e. Ra-LPS, a rough mutant with truncated headgroups, and BsLTA, extracted from Bacillus Subtilis bacteria species. The influence of monovalent (Na+), divalent (Ca2+) and trivalent (La3+) cations and a quadruply-charged peptide (four-antennary oligoglycines) on membrane structure, elasticity and integrity has been investigated, as a function of ionic strength (3-30 mM) and temperature (25 and 40oC). The classic Langmuir-Blodgett trough has been used to evaluate physicochemical properties of bacterial lipid monolayers, shedding light on the underpinning molecular interactions. In situ Brewster angle microscopy (BAM), synchrotron X-ray reflectivity (XRR), and neutron reflectivity (NR) provided complementary structural insights. These unprecedented results lead to a better understanding of the mechanisms of the bacterial membrane structure and elastic properties changes chal

The human brain is a complex organ, thus unsurprisingly a neurodegenerative disease like dementia has no medical cure. However, when facing "wicked problems" that is when design and creativity flourish. This thesis takes a design approach to explore the complex social concept of interdependence and how it can shape technologies to support people living with dementia -- specifically looking at supporting social interactions in community spaces. To situate our design work we aimed to identify the structures around social programs for people living with dementia that occurred in community settings. To understand interdependence in the context of social programs we needed to expand the existing interdependence framework to incorporate contextual or organizational interdependencies. We then conducted a long-term community-based participatory design study with members of the dementia community in Bristol, UK. This process allowed us to identify the value of this methodology in discovering opportunities for designing in positive interdependencies. Furthermore, this research helped us to inform and filter the design space around developing technologies which could help support positive interdependencies. Through our filtered design space we provide a set of design requirements which we used to develop and test a prototype with members of the dementia community. This test was able to demonstrate the efficacy of our design space by facilitating participants to interdependently move around a community space. Finally, this thesis aims to highlight the current limitations of our understanding of interdependency as a concept and the further research needed.

Representationalism is a promising route to an intelligible and thoroughly naturalist conception of phenomenal experience. Unfortunately, the most thoroughly worked out reductive representationalist accounts are externalist about phenomenal experience. There are several criticisms of phenomenal externalism which rest upon the internalist intuition. Here we develop this line of criticism and articulate a different problem with phenomenal externalism: the unintelligibility of external determination. This new problem is harder for the reductively minded representationalist to swallow, and places new constraints on the kind of internalist account that would be satisfactory. After establishing the need for a reductive and internalist representationalism we turn to our positive project; providing an account of what it is to be a representation and an account of content determination in a reductive manner, whilst maintaining internalism. This account is a Russellian, projectivist representationalism, where representation is a matter of being used as a representation and representational content is determined by the properties of internal representational structures. One consequence of this position is sensory property structuralism: the properties that we are aware of in sensory experience are essentially structural and their nature exhausted by their relations to one another. Our account is defended and compared with existing accounts that seek to achieve similar goals. Finally we turn to something more speculative. We argue that the account proposed here can be naturally extended to include mental content in general, providing a solution to the content causation problem.

Nutrient enrichment is widely recognised as one of the principal stressors impacting freshwater ecosystems. Managing nutrient sources is vital to restore ecosystem function. However, diffuse water pollution from agriculture presents a challenge in identifying nutrient sources inhibiting the implementation of targeted management practices. To face this challenge, a comprehensive understanding of the nutrient chemistries involved is needed. Therefore, this study aims to investigate nutrient fluxes to link sources from land to stream to determine key contributing source areas within agricultural landscapes and to identify the origins of nutrients in these areas. Nitrogen speciation, phosphorus fractionation, and dissolved organic carbon dynamics were characterised over 22 months using high-resolution temporal and spatial monitoring in an agricultural headwater catchment. The high-resolution approach captured sharp flux variations, enabling nutrient hotspots to be identified. Key differences in nutrient flux rates depended on catchment characteristics such as land use, geology and hydrology. A faecal lipid biomarker approach using sterols and bile acids combined with high-resolution mass spectrometry allowed the targeted identification of anthropogenic sources impacting the catchment. Riverine suspended sediments and bed sediments were analysed to understand the contributing sources of faecal contamination. Ruminants were identified as the dominant faecal source for all sites, while humans were a secondary source. Variations in catchment characteristics impacted the lipid composition of suspended sediments within watercourses. Bed sediment composition was strongly associated with ruminant indicators, showing the catchment's long history with livestock-related pollution. This research demonstrates that high-resolution monitoring of the full nitrogen and phosphorus pool provides a comprehensive understanding of nutrient fluxes necessary to locate hotspots, linki

he task of designing robots to operate at small scales is challenging because traditional approaches to designing robotic systems often do not scale well to smaller domains. Reducing the size of a robot incurs significant limitations for on-board intelligence and mechanical actuation as well as fundamental differences in the interactions between robot and environment. Instead, inspiration can be found in biological systems, where tasks are often achieved by many agents working together to complete tasks that would be impossible for a single agent. Locomotion is often a fundamental requirement of such systems. Therefore, finding ways to induce and control locomotion in small-scale robots is a vital first step towards deploying mobile artificial systems. To this end, new developments in synthesising smart materials that react to stimuli provide valuable opportunities to explore novel approaches for designing controllable small-scale robotic systems. One example is ProtoCellular Materials (PCMs), a film-like soft material that can contract in the presence of light or at higher temperatures. Materials that react to light are of particular interest due to the high spatial and temporal resolution that can be achieved with light, which can allow for independent control of many agents. Morphological factors often play a crucial role in determining the behaviour of both single robots and multi-robot systems. Yet, understanding how to design morphologies of (groups of) robots optimally is a challenge. In this thesis, I study the locomotive potential of PCM morphologies in simulation and build a hardware platform based on the Dynamic Optical Micro-Environment (DOME) to facilitate real world experiments using light-based closed-loop control algorithms. Whilst achieving reliable locomotion with PCMs remains a challenge, this toolset will enable future research into similar types of photo-contractile smart materials, towards the deployment of new locomotive robotic system

Polygenic scores (PGS) have shown great potential for predicting disease risk and stratifying individuals with elevated genetic risks for early screening and intervention in the general population. PGS can also be integrated with epidemiological and statistical genetics methods to help elucidate the causality of disease-associated molecular features and lifestyle risk factors. In this study, I have examined the use of PGS in three epidemiological scenarios, using molecular traits, anthropometric measures, and cardiometabolic outcomes as examples: I. In Chapter 3, I evaluated a method called block jackknife resampled Mendelian randomization in simulated and applied settings. This technique uses jackknife-resampled PGS as the genetic instrument in individual-level Mendelian randomization. I found that this method generates accurate effect estimates whilst alleviating the biases caused by participant overlap when individual-level data is from a single source. II. In Chapter 4, I generated a comprehensive atlas of the correlations between 249 metabolic traits and PGSs of 125 complex traits or diseases in the UK Biobank. I used two examples from each side of the association analyses, namely glycoprotein acetyls and coronary heart disease (CHD), to illustrate the utility of this valuable resource. III. In Chapter 5, I used the PGS for height to explore the associations between early-life exposures and adult CHD. Standing height is largely influenced by infanthood and childhood exposures. PGS-predicted height and PGS-adjusted height residuals are enriched for the genetic and environmental contributors to adult height. Comparisons between their associations and CHD risks highlight the significant contribution of early-life exposure to adult-onset disease. This thesis explores the versatile applications of PGS to understanding potentially causal relationships in epidemiology. Findings highlight the potential of PGS to enhance method development, unravel m

Sloshing describes the behaviour of a liquid inside the structure containing it, and is an important field of research in engineering problems involving liquids. Accurately predicting fluid dynamics and the interaction with the exciting structure, is crucial for designing safe and efficient liquid transport. An overlooked occurrence of sloshing is in the aviation sector, where hydroelastic interaction between lightweight wing structures and distributed internal storage induces intense sloshing conditions, leading to amplified dissipation of the wing dynamics. In analysing the influence of sloshing in systems involving fluid-structure-interaction (FSI), computational fluid dynamics is commonly employed. Mesh-free methods, such as smoothed particle hydrodynamics (SPH), are valuable due to their Lagrangian properties enabling the capture of complex fluid topologies and nonlinear surface dynamics. However, classical SPH approaches based on weak compressibility (WCSPH) often suffer from acoustic effects, resulting in noise in the pressure field and hydrodynamic loading, amplified in intense sloshing conditions and having a detrimental influence on FSI solutions. This work developed an alternative SPH approach based on artificial compressibility (ACSPH), capable of capturing truly incompressible SPH solutions while retaining the beneficial properties of WCSPH schemes. ACSPH was developed and validated against general hydrodynamics problems, highlighting advantageous properties when compared to its weakly compressible counterpart; namely the ability to predict noise-free pressure fields in strong fluid-impacting conditions, with a similar solution cost. Applied to intense sloshing representative of excitation conditions in aircraft wings, with FSI coupling alongside relevant structural models, ACSPH consistently demonstrated excellent prediction of pressure fields and loading. Compared against single- and multi-degree-of-freedom excitation experi

The education system has long been recognised as a site of social reproduction, yet most research tends to focus on mainstream comprehensive or private schools. Choir schools have rarely been explored within prior studies. These are educational institutions which host a small number of choristers who provide music for an attached religious institution. Their significance lies in the fact that they are uniquely positioned between three fields: education, religion and music. Using Bourdieu’s concepts of field, capital and habitus, amongst others that form his field and reproduction theories, this qualitative study will investigate the reproduction of these three fields within the choir school. It will consider how the schools are intertwined with the Church of England, the role this institution plays in the reproduction of cultural values within the school, and how this contributes to the accumulation of cultural capital and the potential conversion of capital between fields. It will also extend Bourdieu’s initial conceptualisation of the family as a field and examine how the familial field forms and shapes the habitus of choristers. Furthermore, this study will draw attention to the lasting effects of involvement within these fields as exemplified in the educational and career trajectories of choristers.

In recent years, carbon dots (CDs) have received widespread attention as non-toxic, fluorescent carbon-based materials with applications in the field of therapeutics, since these nanomaterials are highly biocompatible, and easy to prepare and functionalised. In this study, glucosamine was used as the starting material to synthesize, in a one-step hydrothermal method, amine-coated CDs, which were subsequently functionalized with succinic anhydride to obtain acid-coated CDs. These CDs can be functionalized in many ways via amide coupling, making the nanomaterial a multifunctional platform for therapeutic purposes. In this thesis, two applications of functionalised CDs were pursued, the first part of the work was devoted to exploring the use of CDs for drug delivery applications, while the latter related to developing a platform for gene delivery. Galactose/galactosamine as terminal sugars found on the surface of mammalian cells are known glycans that interact with carbohydrate binding proteins present in for example cancer cells. Thus, multivalent glycan-probes can be used to target cancer cells for drug delivery application, however their affinity and selectivity to specific cancer cells still needs to be further improved. In order to improve their carbohydrate/protein binding affinity, D-galactal was used to synthesize 2-deoxygalactoside (which lacks a substituent at C2) featuring an amino-containing linker, which was subsequently conjugated to acid-coated CDs, to evaluate the effect of the substituent at C2 on the glycoside on the intracellular uptake in cancer HeLa cells. Furthermore, CDs functionalized by this sugar and loaded with Dox were also prepared to explore the drug delivery potential of this system. Cationic polymers are commonly used as gene trapping agents, which can efficiently catch DNA/RNA, but their high cytotoxicity still limits their development and application. C

Spent Advanced Gas-Cooled Reactor (AGR) fuel is interim stored in cooling ponds, and the fuel cladding may suffer from Stress Corrosion Cracking (SCC) due to the combination of the Radiation-Induced Segregation (RIS) and the corrosive environment in the pond. This thesis presents a better understanding of SCC from different aspects of the phenomenon by using a thermally sensitised surrogate material. A new Small Punch Test (SPT) setup was developed that can accelerate the initiation of SCC by introducing a corrosive environment, and some SCCs were observed on the surrogate material after a few days of exposure. Digital Image Correlation (DIC) was performed on the sample with SCC, and several patterns for a corrosive environment were compared. As DIC can only be used to monitor the cracks on the sample surface, an experiment was conducted by implementing X-ray Computed Tomography (XCT). An in-situ corrosion tensile experiment was performed at a synchrotron beamline, and the propagation of SCC was observed in real-time. To understand the relationship between thermal sensitisation and different grain boundary properties, a volume was reconstructed from serial-sectioned Electron Backscatter Diffraction (EBSD) maps from a thermally sensitised 304 stainless steel, and the remaining material was mapped by Energy-Dispersive X-ray Spectroscopy (EDS).

Microscopy is one of the most prevalent techniques in biological research for observation in microcosms. Driven by advances in microscope technology, biological image processing techniques have become increasingly relevant. The recent achievements in image-processing approaches based on machine learning help make inestimable contributions to biological research. It is a promising avenue for breaking the boundaries between biological research and state-of-the-art engineering techniques. Biological images have nevertheless limitations in practical applications. The work in this doctoral thesis aims to leverage deep learning methods to find solutions that mitigate such limitations and extend the application of microscopy. I focus specifically on the tasks of biological image translation and registration. We start with an example application of microscopy to observe specimens raised in culture dishes, which can exhibit random displacement. Image registration for a series of images can contribute to the observation of detail changes over time in such a situation. A primary challenge for biological image registration is that the rotation angle and translation distance are completely arbitrary. I provide a model that extracts features of interest (FOI) from pairs of images and calculates the correlation among these FOIs. I introduce a feature-detector-free model based on feature point matching predicting parameters to constitute the affine transformation matrices and transform the moving images into fixed images. %This approach aims to implement registration by accounting for the spatial restriction. Furthermore, fluorescent microscopy is a special type of optical microscopy that labels specific structures of specimens for observation. However, the process of sample labelling is time-consuming and laborious and occasionally subsequent sample damage arises from these labels. In particular cases, fluorescent images are necessities, but labelling ex

Micro-RNAs (miRNAs) are short non-coding RNAs that modulate gene expression at the post- transcriptional level. This is achieved through associations with Argonaute (Ago), a protein within the RNA-induced silencing complex (RISC). Specific miRNAs are required for NMDAR- dependent synaptic plasticity, through tight regulation of proteins involved in dendritic spine morphology, such as Limk1. NMDAR-dependent suppression of Limk1 via miR-134 is vital for dendritic spine shrinkage and requires phosphorylation of Ago2 at S387. NMDAR-dependent S387 phosphorylation also increases Ago2:DDX6 interactions. Dead box protein DDX6 is an RNA helicase that has been implicated in RISC function and RNA interference processes, though a specific role for DDX6 in neuronal gene silencing has yet to be established. In the context of progenitor cell differentiation and viral pathogenicity, DDX6 has been shown to preferentially associate with specific mRNAs through various secondary structures present within their 3’UTR. DDX6 helicase activity has the potential to modulate miRNA-dependent silencing, based on the regulatory action it has on secondary structures within the 3’UTR of mRNAs. It is unclear if the helicase activity of DDX6 shows specificity toward the miRNAs to which it preferentially binds. Here I provide tentative evidence that knockdown of DDX6 blocks the NMDAR-dependent decrease of Limk1, regulated via miR-134, whilst knockdown of DDX6 has no effect on NMDAR-dependent repression of Apt1, regulated by miR-138. This work suggests that DDX6 could show specificity during RNA interference processes and highlights this mechanism as an avenue for further investigation.

In this dissertation I explore the concept of vedanā (‘feeling’) in the early Buddhist texts, primarily those preserved in Pali. I argue that some recent attempts at understanding vedanā have relied too heavily on modern psychological models, leading to reductive views that exclude from it the emotions of happiness and sadness, misplacing the line that separates feelings from evaluations, and obscuring how vedanā makes sense fully in the context of Buddhist doctrine and ethics. I also defend that pīti (joy) is roughly synonymous with somanassa (happiness), and therefore can be treated as a feeling in the early discourses. This reveals a hedonic curve—going first to pleasant feelings, then to neutral ones—common across all major formulas and models of progress to awakening, suggesting that, from the affective-hedonic viewpoint of vedanā, the early Pali discourses present a consistent theory of liberation. I explore how these early texts use the motivational aspect of feelings to help practitioners advance towards liberation, by sublimating the natural turning away from the unpleasant into renunciation, and the natural pursuit of pleasure into seeking what is good and skilful. On this basis, they encourage practitioners to derive satisfaction from the disappearance of unskilful behaviours and mental factors, then to extend this capacity to access meditative states, and to delight in simplifying phenomenal experience even more. A consistent vedanā transformation underlies early Buddhist soteriology, which emerges as a form of refined hedonism.

The multifaceted crisis of society and nature is exacerbated by the crisis of imagination - what Mark Fisher called Capitalist Realism. The crisis of thinking, this thesis argues, is an objective expression of the antagonistic social relations between thinking and doing, the one person and the other. Its origins are traced to the praxis of commodity exchange, a praxis that postulates the aesthetics of abstraction, obliviousness, and egoism. These little crises are so endemic and mundane that they are perceived as no crises at all. It is for this reason that this thesis attends to the utopian potential of the everyday, by establishing a community of cleaners, librarians, and porters at the University of Bristol. By synthesizing methodologies from social sciences and design, the community went through a process that was participatory, speculative, and open-ended. From the hidden realities of reproductive work, to postcards from the future, to science fiction hoovers, the collective creation of art mediated new sensory relations. These transcended the aesthetics imposed by the abstraction and division of waged labour, and nurtured utopian imagination. What resulted from the fieldwork is the advancement of Aesthetic Materialism as a theoretical framework for praxis-based research, and a methodology that mobilizes it in the field. The latter comprises two foundational processes. The first concerns the use of art as the means of estrangement and the perception of reality as weird and eerie. The weird concretion becomes the springboard for the creation of a utopian vision, in a process that is termed the warm abstraction. When done well, the two processes engage in a reciprocal relation that produces practices and situations that intensify social relations. The proposed methodology aspires to be sensitive enough to move dialectically within our fragile present, yet imaginative enough to allude to the transformation of capitalist social relations.

Surgical innovations are often adopted into clinical practice before being adequately evaluated. Approaches to evaluating surgical innovations such as the IDEAL framework model surgical innovation as ‘stages of innovation’. Determining the stage of innovation may be difficult. There is a need for a better understanding of stage of innovation to facilitate more robust evaluations of surgical innovations, enabling patients to make informed choices about their treatment. The aim of this thesis is to understand the concept of stage of innovation and how it may be informed by sources of information available to surgeons and researchers in real-world contexts. The thesis consists of two parts: a systematic review of literature and an ethnographic case study of a surgical innovation. The systematic review aimed to understand the concept of stage of innovation described in the literature. It revealed that stages of innovation were characterised in terms of ‘indicator’ parameters such as numbers of patients involved. Determining stage of innovation from literature was problematic due to a lack of knowledge of IDEAL, limited availability of information, unclear definitions of stages and confusion surrounding staging individual studies versus the innovation overall. A case study of aortic valve neocuspidisation with autologous pericardium was conducted to understand how stage of innovation could be determined contemporaneously in a real-world context. Eighteen semi-structured interviews with five surgeons were conducted and thematically analysed. Ten operations were video-recorded and three were analysed using a novel method. Findings from the systematic review, interviews and video-recordings were triangulated. This in-depth study demonstrated how stage-related information could be obtained by interviewing surgeons and video-recording operations. This work supports and enables the use of surgeon interviews and video-recordings as complementary sources of inf

This thesis considers the philosophy and landscapes of Henry St John, Viscount Bolingbroke (1678-1751). Although a significant political figure, his voluminous writing on philosophy has been dismissed as incoherent, a form of Deism, or reduced to socio-political issues. On the contrary, his philosophy is found to be a largely systematic whole. It is related to his two designed landscapes, one of which is an early example of a ferme ornée. A broadly hermeneutic approach is taken to Bolingbroke’s notoriously contradictory thought, which revisions it as a dialectic demonstrating the influence of intellectual traditions and their unconscious expression. The investigation puts more emphasis on concepts and the guiding force of philosophical reasoning than is usual in garden history. The key finding is that Bolingbroke’s philosophy is a systematic attempt to unify the areas of natural philosophy, theology and morality with an argument for a way to moral truth based on an idea of nature. Despite claiming to follow Locke’s epistemological method, Bolingbroke, in effect, asserts a direct realism. The highly ambiguous contemporary concept of nature is revealed to have a pivotal meaning as the idea of form or essence, and this reflects a largely assumed Aristotelianism in which teleology and normativity are central. This has its major application in the context of morality where ‘human nature’ provides the promised middle way between the absolutism of Plato and the relativism of Protagoras; a duality also applied to Locke and Hobbes. The role of a deity, which has otherwise been the subject of some dismissal in Bolingbroke’s thought, is clarified. The idea of human nature is found to be central to Bolingbroke’s thought, and this guides the approach to his landscapes, which are viewed as embodiments of a concern with questions of the nature of a person and how to live.

Petroleum hydrocarbon-polluted environments harbour diverse microbial communities but their response to oil pollution is poorly constrained. Here, the effects of petroleum hydrocarbons (from seepages and spillages) and the associated heavy metals on oil-contaminated soils, including agricultural soils (grazeland and farmland soils), have been explored. Furthermore, the response and the distribution of the soil microbial community due to oil degradation have been assessed. Focus was made not only on the commonly studied phospholipid fatty acids (PLFAs) but also widened to include archaeal intact polar lipid (IPL), isoprenoidal glycerol dialkyl glycerol tetraethers (isoGDGTs), and branched (bacterial) glycerol dialkyl glycerol tetraethers (brGDGTs) in oil-contaminated environments. Soil microbial communities represent an indispensable component responsible for the majority of soil ecosystem services. The production and decomposition of plant materials and the associated formation of humus (C-sequestration) would be hindered without soil microorganisms. Estimating microbial mass fractions is often used as a general indicator of soil biological activity to determine soil health and stress. In particular, how these microorganisms respond to petroleum hydrocarbon contaminants in an oil-contaminated environment remains an open question. To begin with, the well-head crudes (onshore and offshore) and seepages were characterised by petroleum biomarkers to investigate their source(s). The PCA of the hopanes show that Ugwueme and Ehandiagu seepage, together with all the studied oil samples, have a common source (originating from a higher plants/terrestrial and open marine source rock). In contrast, Edda 1 seepage originates from plankton/algae and has a minimal contribution from terrestrial plant material. The microbial population in seepage-contaminated soils was characterised. The distributions of bacterial and fungal microorganisms inferred by PLFA and GDGT soil

We consider eukaryotic DNA replication and in particular the role of replication origins in this process. We focus on origins which are 'active' - that is, trigger themselves in the process before being read by the replication forks of other origins. We initially consider the spacings of these active replication origins in comparison to certain probability distributions of spacings taken from random matrix theory. We see how the spacings between neighbouring eigenvalues from certain collections of random matrices have some potential for modelling the spacing between active origins. This suitability can be further augmented with the use of uniform thinning which acts as a continuous deformation between correlated eigenvalue spacings and exponential (Poissonian) spacings. We model the process as a modified 2D Poisson process with an added exclusion rule to identify active points based on their position on the chromosome and trigger time relative to other origins. We see how this can be reduced to a stochastic geometry problem and show analytically that two active origins are unlikely to be close together, regardless of how many non-active points are between them. In particular, we see how these active origins repel linearly. We compare results from both of these models using genetic data from several different organisms and use regression analyses to highlight their key characteristics, in particular the local repulsion and tail behaviour. Additionally, we look at related probabilistic models to modelling DNA replication, in particular polynuclear growth, and draw comparisons between the two. We finish our analysis by considering replication time, which is important in the genetics literature, and how this is represented in our stochastic models. We consider possible approaches from extreme value theory as well as results from probability literature.

Blood group antigens are inherited traits present on erythrocyte membranes and other tissues, that are defined by alloantibodies. These are immune antibodies produced in response to exposure to incompatible red blood cell antigens through pregnancy, transfusion, or transplantation. Additionally, some antibodies to blood groups, such as those in the ABO system, are naturally occurring due to the presence of similar antigens on common environmental substances like bacteria and food. To date, there are 362 authenticated blood group antigens classified in 45 human blood group systems that have been recognized by the International Society of Blood Transfusion (ISBT). However, the molecular background of some antigens remains uncharacterized. These uncharacterized antigens, whose molecular basis is yet to be determined, may either define a new antigen within an existing system or constitute a novel blood group system. The research in this thesis focused on investigating uncharacterized and unmapped erythrocyte antigens. We utilized the International Blood Group Reference Laboratory (IBGRL) archived rare sera and red cell samples for this purpose. We employed a genomic approach, utilizing whole exome sequencing and followed by Sanger sequencing to identify the genetic alterations responsible for these antigens. In vitro expression studies, including both CRISPR Cas9 knock-out and over-expression of genes of interest were conducted to confirm the molecular basis. This work revealed that PIEZO1 is responsible for the expression of the Er antigens (Era, Erb, Er3, Er4, Er5), establishing the Er blood group system. Furthermore, we identified MAL as the gene responsible for the expression of the AnWj high prevalence antigen and establishing a further blood group system. We also identified and characterised a novel high prevalence antigen, subsequently assigned to the Lutheran blood group system (LUOM).

The growing adoption of Fiber-Reinforced Polymer (FRP) materials in structural applications has brought to the forefront the pressing issue of their recycling and associated environmental impacts. Mitigating these concerns hinges on the development of ease of disassembly, repair, replacement, and recycling to enable the circular economy of FRP structures. This endeavour aligns with the broader objective of promoting sustainability and embracing the principles of a circular economy for FRP materials. This academic study is dedicated to shedding light on the intricate processes underlying the formulation and evaluation of such adhesive systems. The research begins by developing a debond-on-demand methodology using a hot melt adhesive (HMA) as a prototype controlled by induction heating. Followed by exploring various adhesive formulations, initially considering epoxy, and polyurethane systems. The epoxy uses a disulfide-based epoxy resin, EPS 35, which initially showing promise due to its reported self-healing properties. However, challenges in achieving the desired debonding properties prompt a shift towards polyurethane formulations. The successful polyurethane adhesive formulations are modified by the introduction of various polyols with varying functionalities. An extensive rheological analysis is conducted to assess changes in viscosity upon heating and ascertain the potential for debond-on-demand behaviour. The study investigates the relationship between the choice of polyols, cross-linking density, and shear strength, ultimately identifying formulations that exhibit the desired debond-on-demand properties suitable. The chosen PU adhesive formulation, designated PU15N, serves as a baseline with a single lap shear strength of 7 MPa and a 30-minute debonded time facilitated by the developed debonding methodology of induction heating. Subsequently, the study examines the incorporation of iron oxides in various forms and weight fractions to explore their impact o

Episodic memory (EM) is the ability to recall a specific episode, such as the temporal sequence (when), the spatial setting (where) and the people or the objects involved (“what”) in a spatiotemporal context. However, encoding highly similar episodes and places in EM needs to be optimised by a memory discrimination process called pattern separation performed by the hippocampal dentate gyrus (hDG) circuitry. Excitatory hilar mossy cells (MCs) are involved in pattern separation through their connections with different inhibitory interneuron populations, providing net feedback inhibition to granule cells (GCs) in the hDG circuitry. In this study, I investigated how MCs and their synaptic connections with parvalbumin-expressing interneurons (PVIs) influence the dynamics of hDG circuitry by using pharmacological agents to reduce neurotransmission from MCs, genetically modified (GM) mice to selectively remove MCs from hDG circuitry and optogenetics to manipulate the activity of PVIs during GC whole cell/field recordings. Additionally, I used GM animals that lack MCs to distinguish between the long-range projections of MCs and cholecystokinin-expressing interneurons (CCKIs) in hDG circuitry. My results showed that 1) Genetic deletion of MCs from hDG circuitry disinhibited GC responses to medial perforant pathway (MPP) stimulation at 10 Hz, 20 Hz and 50 Hz, but not 5 Hz. 2) Pharmacological inhibition of MCs disinhibited GC responses to MPP stimulation at 10 Hz, 20 Hz and 50 Hz, but not 5 Hz. 3) Optogenetic activation of PVIs partially normalized GC responses to MPP stimulation at 10 Hz in GM animals. 4) MCs that express CCK neuropeptides, but not CCKIs, form long-range axonal projections to ipsilateral distal and contralateral hDG. These findings suggest that the MCs regulate GC responses to MPP stimulation by recruiting interneurons at frequencies associated with pattern separation processing in the hDG.

This body of work outlines the results of a theoretical investigation into the effects of external strain on superconductivity. This effect is explored for various gap pairings, for superconductors that can be modelled on a square lattice. Using some general predictions of group theory and a microscopic negative-U Hubbard model, the change in the critical temperature (Tc), with applied strain, via hopping anisotropy, is systematically explored for some s, p and d-wave models of superconductivity. The pairing states explored are done in conjunction with parameters that reproduce the properties of Sr2RuO4, a material surrounded in uncertainty and with a detailed set of external strain experiments. In direct comparison with these experiments it is found that a d + ig pairing state best describes Sr2RuO4 with all available experimental evidence considered. The generality of the model is of key importance as it is used to make predictions for the change in Tc with applied strain for La2−xSrxCuO4 (LSCO). The applied strain pushes the Fermi surface through a topological change known as the Lifshitz transition. The leading cause for the change in Tc, in all cases, is found to be the orientation of symmetry imposed superconducting gap nodes. If they are coincident with the opening of the Fermi surface there’s an expected decrease in Tc or if they are non-coincident a predicted increase in Tc is seen as the system passes through the topological Lifshitz point causing a van Hove singularity (vHs) in the Density of States (DOS) to move through the Fermi level or not. The framework outlined within this thesis provides a general model applicable to many pairing states in two dimensions and applications to other superconductors can be readily applied.

Over the past few decades, there has been a substantial increase in network bandwidth, accompanied by significant advancements in network technologies. As a result, there arose a demand for specialized hardware capable of relieving network-related workloads from the CPU. In response, the Smart NIC, a more intelligent network interface card, was introduced to alleviate the burden on server throughput. The journey of my PhD work and thesis commenced with an exploration of both established and emerging Smart NIC technologies. The overarching objective was to harness FPGA technology to design and implement an innovative and universal Smart NIC architecture. This architecture was engineered to efficiently offload CPU workloads in common usage scenarios, particularly within Cloud and Telecom networks. Given the adaptable nature of the NIC/Smart NIC, designed to seamlessly integrate with a range of hardware and operating systems, I leveraged various Open Source standards to develop a comprehensive FPGA-based Smart NIC solution. This solution encompassed both hardware and software components, contributing to the acceleration of intra- and inter-server networking. The focus of my PhD thesis was directed towards the design and implementation of the FPGA-based components. I chose P4 as the foundational architecture, providing the necessary programmability and flexibility to meet our objectives. Multiple algorithms were devised to enhance throughput and reduce latency, with a particular emphasis on two scenarios: intra-server Open Virtual Switch offloading and inter-server Segment Routing. To validate the effectiveness of our approach, a series of experiments were conducted, utilizing intraand inter-server use cases. The results of these experiments served as compelling evidence, showcasing the substantial improvements achieved through the deployment of Smart NIC technology. This encompassed enhance

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder that is associated with atypical reward processing and low motivation. Reward processing is a complex behaviour that helps organisms to respond to, become motivated for, and learn from, rewards in their environment. Some theorists have suggested that reward processing and associated deficits of motivation, should be considered aetiologically characteristic of ADHD. Despite decades of research, explicating exact differences in reward processing and motivation between groups with and without ADHD, has proven to be a complex challenge. Reward and ADHD research suffers from a lack of diverse methodology and restricted sampling strategies. The current thesis adds to existing literature by (1) investigating reward motivation and intrinsic motivation in an analogue sample split by level of ADHD traits, (2) studying reward motivation using a combination of objective and subjective measures, and (3) applying qualitative methodology to explore subjective experiences of reward in adults diagnosed with ADHD. Study 1 results suggested reward motivation, as measured using the Effort Expenditure for Rewards Task (EEfRT) and the Joystick-Operated Runway Task (JORT), is not affected by level of ADHD traits. Furthermore, intrinsic motivation, as measured using the Multidimensional Personality Questionnaire, is not affected by level of ADHD traits. Study 2 provides qualitative evidence of how rewards are experienced in daily life by adults with ADHD. Several similarities and differences between theoretical understanding of reward processing in ADHD and lived experience of rewards provided by adults diagnosed with ADHD, are highlighted throughout study 2. In summary, our results show that reward processing may not be affected by traits of ADHD, until such traits reach diagnostic thresholds, at which point, they become influential on one’s daily interactions with rewards. Implications of these findings

High aspect ratio wings (HARW) can provide higher lift-over-drag ratios leading to longer ranges through the resulting reduction in the induced drag. However, the increased structural flexibility inherent in HARWs renders them more susceptible to significant deflections under identical operating conditions compared to wings with lower aspect ratios. This increased flexibility can adversely impact the dynamic and aeroelastic behavior of the wings, potentially precipitating aeroelastic instabilities at lower velocities than those observed in comparatively stiffer wing structures. Furthermore, the presence of geometric nonlinearities in very flexible wings complicates the prediction of their static and dynamic behaviors, rendering conventional linear modelling approaches inadequate. Besides, the design of high aspect ratio wings also confronts operational constraints, particularly within airport environments, which can be solved by the introduction of folding wingtips that can reduce the span for airport compatibility. Further work has shown that the use of floating folding wingtips enables significant gust loads alleviation and improved roll behaviour, however, a large deformation of the folding wingtip can also introduce geometric nonlinearities that significantly affect the overall aircraft performance. Therefore, it is of paramount importance to incorporate the impact of geometric nonlinearities on the aeroelastic response in the realm of HARW design. In the context of optimizing HARWs incorporating floating folding wingtips, or not, there are currently few robust or reliability-based optimization studies that considers input parameter uncertainties within the design process. This thesis develops a robust and reliability-based design optimization process to consider input parameter uncertainties in high aspect ratio wing designs including geometric nonlinear effects. Wing weight min

Bees are paramount as pollinators, crucial for ecosystem health, biodiversity preservation, and successful crop production. Recognising and conserving their populations is imperative in order to sustain these invaluable ecological services. Using this information, this thesis has the objective to investigate if there is a preference of the pollinator buff-tailed bumblebees (Bombus terrestris), for moving or stationary artificial flowers; the preference behaviour exhibited between the two flower types, and the difference in movement between several species of flowers, preference was looked at due to the gap in research on this area and the wider implications this may have for agriculturists. The experiment was designed to alter rewarding and non-rewarding liquids between the moving and stationary flowers, changing after each experiment, this allowed the foragers to learn and to indicate if there was a preference between the types of flowers. Experimental observations revealed a significant difference in preference towards moving flowers rather than stationary ones. The distance of movement of seven different species of flowers (Lavandula angustifolia, Agapanthus inapertus, Fuchsia magellanica, Rudbeckia fulgida, Impatiens balfourii, Tulbaghia violacea, Anemone hupehensis) was also explored when exposed to wind, the species of Fuchsia moved the furthest out of the seven species of flowers recorded. The preference shown by Bumblebees with moving flowers rather than stationary flowers may be explained by novelty behaviour as these bumblebees had never experienced moving flowers due to their life in a laboratory. This research holds significant implications for agriculturists and conservationists by informing the selection of plants that attract bumblebees. Understanding the impact of flower movement on bumblebee behaviour allows for the strategic choice of plants with specific morpho

This thesis investigated the relationship between foreign direct investment (FDI) and democracy, specifically examining whether investment from the United States and China is associated with a change in the level of democracy in recipient nations. To achieve this, we employed a Generalised Methods of Moments (GMM) estimator, using panel data covering a 17-year period for China and a 38-year period for the United States. For China, we detected a significant negative relationship between FDI and democracy, suggesting that an increase in Chinese FDI may be associated with a decrease in the level of democracy in recipient nations. By contrast, for the United States, no significant relationship was detected between FDI and democracy, implying that investment from the United States is not associated with changes in democratic levels in these countries. We conclude by discussing the implications of these findings and suggest directions for future research.

The known population of planets in our universe is highly diverse, spanning system configurations, masses and radii, and compositions beyond anything seen in our Solar System. In order to understand this complex picture, explorations of their atmospheres have begun to characterise exoplanets in more detail, with space-based telescopes proving an invaluable tool in this effort. By combining transmission spectroscopy observations, which search for wavelength-dependent changes in a planet’s transit depth caused by its atmosphere, with comprehensive modelling efforts, we are able to probe the key processes at play within these atmospheres. I present transmission spectra and the inferences gained for three planetary systems from the largest, fluffiest gas giants down to a sub-Neptune and super-Earth pair. Combining new Hubble observations with Spitzer photometry, I produced the transmission spectrum of the hot Jupiter WASP-17b, and used a comprehensive suite of atmospheric retrieval models to explore the potential range of compositions allowed by the data, unearthing a degeneracy in the metallicity of the atmosphere. At the dawn of the JWST era, I developed an end-to-end open-source reduction pipeline, ExoTiC-JEDI, designed for analysing transmission observations obtained by the NIRSpec instrument. Using JWST as part of the ERS Transiting Exoplanet Early Release Science Program, I led the analysis of the hot Saturn WASP-39b, as observed with the NIRSpec/G395H mode, identifying the presence of sulphur dioxide, a molecule produced by photochemical reactions in the upper atmosphere. Revisiting WASP-17b, I took a second look at its atmosphere, now with JWST, to reassess the results provided by Hubble and refine the true nature of its composition. Since exploring smaller mass planets often requires brighter host stars, I pushed JWST to its limits by analysing the atmospheres of the sub-Neptune and super-Earth orb

This research was undertaken to investigate the feasibility of implementing thrust vectoring as a supplementary flight control system on civil transport aircraft. The motivation for this research was to explore loss of control in flight (LOC-I) mitigative strategies in the form of an alternative but dissimilar flight control technology, since thrust vectoring is inherently less dependent on aerodynamic effects than traditional surfaces. The research was conducted as a comparative study between conventional control surfaces and thrust vectoring under normal and abnormal flight conditions, and the operational boundaries of civil thrust vectoring were systematically quantified through comprehensive simulations and analyses. Desktop flight simulations were performed using the Transport Class Model (TCM) aircraft model developed by the National Aeronautics and Space Administration (NASA), representative of an underwing twin-engine configuration in line with current aircraft design trends. The project was split into four phases to comprehensively evaluate aircraft behaviour in a wide range of scenarios. The first two phases focused on evaluating and comparing flight control effectiveness and aircraft controllability metrics respectively, while the last two examined the role of thrust vectoring as a backup flight control system in control surface failure events and aircraft upset conditions, respectively. Comparative analyses were conducted at different flight phases to highlight the advantages and limitations of thrust vectoring over conventional control systems across a typical civil flight profile. The results demonstrated a general deficit of control effectiveness of thrust vectoring compared to conventional controls on civil transport aircraft due to their low thrust to weight ratio (TWR), however it was still capable of completing standardised manoeuvres to a satisfactory level. In addition, thrust vectoring was shown to mitigate the adverse effects of LOC

Women with learning disabilities experience a range of disadvantages across the life course including; social isolation and marginalisation, increased risk of experiencing severe, frequent, and repeated incidents of domestic violence and abuse (DVA), the normalisation of violence and abuse throughout the life course, inquiries into their abilities as mothers, and barriers to accessing effective support services. These experiences impact upon their conceptualisations and experiences of fairness and unfairness. Seven participants were recruited via two services that specifically support people with learning disabilities who have experienced DVA. Each participant took part in a semi structured interview which explored their understandings and experiences of fairness and unfairness in relation to their engagement with support services responding to DVA. Within the context of this research DVA services are defined as any public or private service a person is engaged with in response to experiencing DVA, including but not limited to, the police, adult social services, children’s social services, DVA programs, mental health practitioners, housing officers, and community groups etc. Interpretative phenomenological analysis revealed the complexity of their experiences, with participants reporting what it means to be treated fairly and unfairly when engaging with DVA services, the importance of relationships in making sense of fairness and unfairness, the lack of accessible preventative services, the impact of ableist attitudes on their engagement with DVA services, institutional barriers to accessing DVA services, and the adverse consequences of unfair experiences of interventions from DVA services. To examine the relationship between fairness and unfairness, people with learning disabilities, and DVA services, it was important to explore how fairness and unfairness can be defined and experienced. This thesis presents an experiential definition of fairness and

Heterogeneous multi-agent systems are composed of diverse and autonomous agents that can interact and cooperate to achieve complex goals. Human history from the formation of social groups to technological systems such as the Internet has shown that greater functionality is achieved in interconnected systems. It is therefore expected that advances in artificial intelligence and autonomy will lead to diverse types of ever more capable robotic and software agents interacting in order to enhance their capabilities. In applications including logistics, disaster relief and social care, these heterogeneous agents can bring different perspectives, skills, and resources to a system, enhancing its adaptability, robustness, and creativity. And yet, despite the benefits, it is not clear what constitutes heterogeneity in this context or how to frame it as a property in system design. Without answering these questions, there is a risk that the full benefits of multi-agent systems are not realised, and that their collective behaviour either surprises or at worst is detrimental to those it is intended to serve. This thesis addresses the need to understand what heterogeneity means in the context of a multi-agent system, and the tools and techniques to employ different agent types effectively in system design. It explores how the context, task and agent interactions, in conjunction with the number of agent types and their distribution can influence how heterogeneity is framed and the methods used to measure it. The research also investigates general design principles to facilitate knowledge transfer between applications, thereby reducing development time and the risk of failures. Application agnostic techniques based on the information-theoretic measure of Empowerment and Evolution are investigated to create successful interactions between agents regardless of their type. Additionally, the concepts of influence, traits, and ecological framing of diversity

The energy consumption of modern mobile networks is coming into more focus, with the need to meet net zero and reduce network energy costs, where the power amplifier can be a major consumption contributor. Mobile networks are also expanding in the spectrum used, requiring an increased investment in infrastructure to cover this spectrum. This thesis therefore focuses on the design and implementation of novel techniques for both high efficiency and bandwidth performance in radio frequency power amplifiers, in an effort to alleviate both energy concerns and future infrastructure investment costs. The first main topic is based around Continuous Modes, where Class J and Continuous Inverse Class F are examined using a real transistor device. It is proposed that a combination of these two modes can be used to achieve high mean efficiency across the bandwidth of a power amplifier, mitigating any loss of performance due to the knee voltage effect in a real device. This combination of modes is used in the design and fabrication of a wideband and dual-band power amplifier, where a high mean drain efficiency greater than 73 % is achieved in both. When comparing with state of the art, this combination of modes for both power amplifiers is unique. Detailed in this thesis is a design methodology for an asymmetrical Doherty Power Amplifier which achieves a high average efficiency at back-off across its operating bandwidth. This design implements some of the findings from the investigation into continuous mode Doherty power amplifiers, including an optimum combination of 2nd and 3rd harmonic impedances, and also the use of the drain supply as a design parameter. The design and manufacture of a prototype Doherty power amplifier is then detailed, which operates between 2.1 to 3.2 GHz with a power of between 43.9 and 44.5 dBm, and a high mean drain efficiency of 64.7 % at 8-9 dB of power back-off ac

Orpheus is a mythical figure that has been prevalent in both art and literature since antiquity, and continues to be received today across a variety of mediums. As such, this thesis first explores how Orpheus was characterised in antiquity through engagement with Apollonius’ Argonautica, Virgil’s Georgics and Ovid’s Metamorphoses. Through close analysis of each source, the Orpheus of antiquity can be understood through his changefulness of shape and intrinsic association with desire. Here, he is a being in perpetual flux. Then, working within the framework set out by his ancient portrayals, this thesis explores three modern interpretations of Orpheus, each written by women. First, Anne Wroe’s Orpheus: The Song of Life (2011) is considered through its positioning of Orpheus as a muse, capable of providing inspiration and identification to a modern woman writer. Then, Diane Wakoski’s Medea the Sorceress (1991) is studied through its engagement with Orpheus and desire, wherein selected poems explore the conflict between – and thus consequences of – the desire to have and the desire to become. Lastly, Céline Sciamma’s Portrait of a Lady on Fire (2019) is considered both as a retelling and a meditation on the shifting of selves that is inherent in an Orphic figure. This thesis intends to determine the extent to which Orpheus’ classical origins influence his modern incarnations, and to emphasise his association with the liminal that has persisted across varying centuries and media. The fluidity of Orpheus’ being is positioned not solely as a modern ascription, but as something that he has always been intimately connected to. It is this fluidity that allows for his continued engagement today; he is other, beyond, one who is perpetually reaching, and we reach in turn.

Migration and housing are closely linked. When migrants choose a new location, they also choose a new property to reside in. Despite being so central to one’s well-being and standard of living, the influence of the housing market on migrants’ intentions to stay in the destination country has received relatively less research attention. This dissertation seeks to address this gap by exploring the extent to which satisfaction with housing can influence the length of intended stay by migrant workers in the destination country. This dissertation focuses on Malta, which is a small open economy and a member of the European Union. Malta offers an interesting case study, because in the decade prior to 2021, its population increased by 25%, mostly due to a strong influx of migrant workers. Its private rental market was ill-prepared to deal with this demand, given the absence of regulation, resulting in abuses and affordability concerns. Data collection for the dissertation research relies on primary sources obtained from two surveys. The first one consisted of an online survey conducted in 2019 based on a non-probability sample targeting migrant workers that used to work in Malta but had since left the country (N=242). The second survey was conducted in 2021 with migrant workers in Malta who reside in private rental accommodation (N=495). The second survey was based on a probability sample that used the rent register of the Housing Authority – established as part of a holistic rent reform introduced in 2020 – as the sampling frame. Both surveys provided valuable additions to the knowledge about the population of migrant workers in Malta and were instrumental in overcoming official data limitations. Eight research hypotheses are proposed and tested in two empirical chapters using multinomial and ordered logit models. Among the key findings, respondents who were dissatisfied with their housing were more likely to switch towards a shorter stay than init

Introduction Malignant pleural effusion (MPE) affects up to 15% of patients with cancer (1). Effective symptom control is paramount, given a median survival of 3 to 12 months (2). The mainstay of management relies on fluid drainage from the chest cavity for breathlessness relief, followed by attempted pleurodesis (to prevent fluid recurrence) or indwelling pleural catheter (IPC) placement. However, pleurodesis fails in approximately 20% of cases (3) and long-term IPC placement may be undesirable. Methods A systematic review and network meta-analysis (NMA) summarised current evidence and aimed to ascertain the most effective pleurodesis agent. Building on review findings, two studies aimed to characterise patients at risk of pleurodesis failure. Finally, a randomised controlled trial (RCT) was undertaken to determine whether existing interventions for MPE may be combined to provide more effective symptom control and reduced time in hospital compared to standard care. Qualitative interviews explored the patient experience of the interventions. Results In the systematic review and NMA, talc slurry and talc poudrage were both effective pleurodesis agents. A higher risk of pleurodesis failure was observed with IPC use, but reduced risk of requiring a repeat invasive procedure. When seeking to characterise patients at risk of pleurodesis failure, no features were associated with non-expandable lung. A novel biomarker was not associated with an increased risk of MPE loculation. Results from the TACTIC RCT are awaited. Recruitment is complete, with 124 participants randomised across 11 UK centres. Qualitative analysis is ongoing, but findings suggest that the combined procedure is acceptable to patients and that outpatient MPE management is preferred. Discussion The systematic review and NMA highlights that patients should have access to a range of interventions, including provision for daily IPC drainage. By combining diagnostic and