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Oliver, Jacob B. "Birthing Attila." Thesis, Aberystwyth University, 2015. http://hdl.handle.net/2160/3a37bc8b-6a4a-470d-ba90-452dfb823617.
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I have termed Birthing Attila a creative-critical project since it is not only a collection of poems, or a critical compendium of methodologies and theories, but an alignment of the two in a mutually illuminating process. My creative work informs my critical, and, reflexively, my critical informs my creative. The Birthing Attila project engages with orthodox narratives of history and ideology, critiquing them, working against linear expectation, and identifying and dramatizing margins of society that are often subordinated or neglected in such discourses. By engaging with New Historicist theory as a creative impetus (see Chapter Three) and exploring other theoretical debates chiefly within feminism and post-colonialism, my poetry is drawn into line with a critical praxis. This critical-creative contact locates Birthing Attila at the confluence of recent work on the 'interfrictions' between theorized inquiry and creative practice. The poems themselves seek to encourage today's readers to look internally and at the world around them, all viewed through a 'time-slipped universe' that adopts three 'worlds' inextricably intertwined - the fall of Rome, the 1980s, and contemporary society. Through the use of a time-slipped space in the creative pieces, fault lines, fractures, and permutations of perception across and embedded within history are explored within poems as well as between them. Birthing Attila fuses time together where clean distinctions between periods and events, and the ability to identify a clear chronology beyond the characters' narrative arcs, are, as with the separation of critical and creative practice in the construction of the project, rendered impossible. Chapter One (Reflections and Influences) explores the range of literary influences on the project and the genesis of the idea of a time-slipped space as a means of critique, focusing principally on the four most central literary figures to the poems' generation: Bret Easton Ellis, Tiffany Atkinson, Charles Bukowski, and Wallace Stevens. Chapter Two (Negotiating Borders and Boundaries) introduces cultural cartography and the ways in which the delineation of borders, boundaries, and 'the other' shape notions of identity, and how, consequently, these often artificial distinctions may be misappropriated for use in nationalist and imperialist dogma in the dominant discourse, particularly as it pertains to the West. Chapter Three (New Historicism and Creative-Critical Practice) seeks to firmly situate the Birthing Attila project along a creative-critical axis and expounds on the reflexive exercise of creative-critical writing. This chapter also explains the decision to employ Marjorie Levinson's New Historicism as a creative springboard, as opposed to viewing New Historicism through a purely critical lens. Chapter Four (Gender and Space) expands on the mapping of the body politic, engages with post-colonial and feminist theory, and investigates notions of time, space, and linearity. Perhaps most crucially, this chapter also explains the role of women in the collection and the choice to consciously exclude them from the poems as a means of critique.
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Katsaroumpas, Ioannis. "Collective labour law in times of economic crisis : theoretical and comparative perspectives." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:1f8bb178-12db-45e6-ba90-0fdcac45429b.
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The thesis explores the interaction of the economic phenomenon of 'economic crisis' with the legal phenomenon of Collective Labour Law (CLL). This interaction is the thesis' main problematique. Rather than undertaking an all-encompassing investigation, it seeks to modestly contribute some new theoretical and comparative perspectives on the problematique. These perspectives are of potential value both to the highly underdeveloped area of the theorisation on economic crises and CLL and to the comparative labour law literature. On the theoretical side, the thesis puts forward a novel Marxist-critical theoretical framework for understanding the crisis' operation of CLL. Building successively on the Marxist-critical insights of a fundamental contradiction between the (capitalism) reproductive and (worker) protective function of CLL, the crisis theories' common assertion of economic rationalisation as the primary crisis response and a joint reading of Gramscian counterhegemony and Habermas' theory of legitimation crisis, a theoretical framework is constructed around a proposed concept: crisis (dis)equilibrium. These (dis)equilibria, which arguably determine the course of CLL's crisis developments are composed of two fundamental opposing forces: the force of economic rationalisation, pushing for reforms dictated by the need for intense capitalist restructuring and the opposing counter-legitimation force, which reflects the level of socio-political threat of withdrawal of support to the prevailing economic system or at least to the reforms dictated by economic rationalisation. The comparative side that serves also as a testing empirical ground for the theoretical framework, consists of an extensive interrogation of the recent crisis CLL trajectories in Greece and the UK. For Greece, the analysis observes and accounts for a dramatic collapse of the pre-crisis protective CLL edifice as a result of multiple and abrupt far-reaching CLL reforms bringing about the neo-liberal crisis movement. Subsequently, the thesis offers a response to why the protective constitutionalisation of CLL rights in Greece failed to prevent the de-construction by designating a de-constitutionalisation triangle of normative spheres. The triangle maps and explains how the neoliberal-oriented EU-IMF bailout conditionality prevailed over domestic-constitutional and transnational labour rights normative spheres through identifying a series of 'strong' and 'weak' legal and non-legal interactions. For the UK, the analysis dismisses a suggestion of a complete stasis during the crisis. Instead, it ascertains and accounts for a further -more gradual- neo-liberal consolidating crisis movement of UK's pre-crisis neo-liberal CLL paradigm. Hence the British crisis movement is described as neo-liberal continuity by consolidation. Very importantly, the thesis observes a significant crisis de-constitutionalisation process of CLL in the UK, which takes the shape of a constitutional attack on the political voice of unions by regulatory reforms. Eventually, the thesis finds a comparative crisis pattern of a 'Great Neo-liberal Convergence' between the two previously diametrically opposite CLL systems, since they moved closer and toward the neo-liberal end during the crisis. The 'neo-liberal convergence' finding is situated as a supportive case for the convergence theorists within the convergence/non-convergence debate over whether the European CLL systems are to converge. Moreover, the analysis demonstrates the explanatory value of the Crisis Equilibrium theoretical framework for understanding the crisis trajectories in both countries and suggests that crisis developments confirm the heteronomy of CLL to the theoreticallyidentified dialectic between the capitalist force of economic rationalisation and the social force of counter-legitimation.
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Bourasseau, Nicolas. "Caractérisation de la propagation d'ondes guidées dans les matériaux sandwichs : Application au contrôle santé des radômes." Valenciennes, 2001. https://ged.uphf.fr/nuxeo/site/esupversions/1839ad61-17a3-45d5-ba90-3d17c9fc259d.
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Humphreys, Adam Richard Copeland. "Kenneth Waltz and the limits of explanatory theory in international relations." Thesis, University of Oxford, 2007. http://ora.ox.ac.uk/objects/uuid:d21f41ff-ba18-453f-ba70-ecb7bf8ec3db.
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Kenneth Waltz's seminal work Theory of international politics (1979) conceptualizes international relations as a complex system in which the structure of the system and the interacting units (sovereign states) that comprise it are mutually affecting. Nevertheless, Waltz seeks to develop a nomothetic theory in which the structure of the international political system is isolated as an independent variable, state behaviour being the dependent variable. Waltz's explanatory strategy is therefore characterized by a deep tension: he treats structure as an independent variable whilst also arguing that structure and units are mutually affecting. Consequently, his systemic theory only generates partial explanations: it indicates how structure affects behaviour, but not how structure interacts with other variables to produce specific behavioural outcomes. This thesis draws on Waltz's theoretical writings, on Waltz's applications of his theory to empirical subjects in international relations (superpower relations during the Cold War, Soviet socialization into international society, and NATO's role after the Cold War), and on a wide range of theoretical literature. It explores the implications of the tension in Waltz's approach for explanatory theory in International Relations. It shows that Waltz's theory cannot ground many of his substantive arguments, that realists who attempt to improve Waltz's theory misunderstand the problems Waltz encounters, and that constructivists are unable to offer causal generalizations about complex systems. It concludes that explanatory theory in International Relations is currently poorly equipped to address complex systems in which structure and units are mutually affecting.
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Dylan, Huw. "The Joint Intelligence Bureau : economic, topographic, and scientific intelligence for Britain's Cold War, 1946-1964." Thesis, Aberystwyth University, 2010. http://hdl.handle.net/2160/6338ec52-6154-47ca-ba92-c6bf092281bf.
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This thesis examines the British Joint Intelligence Bureau (JIB), which, between its creation in 1946 and its end in 1964, gathered, collated and processed topographic, economic, scientific, and atomic intelligence. It did so on an inter-service, national level. The thesis examines the creation of the organisation, in the aftermath of the Second World War, exploring what factors and which people supported the creation of the new agency. It then moves on to examine the work of the JIB in several of its key fields of work, namely topography, economics and monitoring the threat from Soviet nuclear forces, before examining some of the JIB’s international connections and how these contributed to its work. It concludes with an examination of how the JIB begat the Defence Intelligence Staff (DIS). It argues that the creation of the JIB was an appropriate response to the need to centralise and retrench in the intelligence machinery after the War, but that the organisation, in essence, represented a compromise between those who wanted to fully centralise military (and military-relevant) intelligence and those who wished to preserve service independence. Over the course of its existence it made important contributions to several key areas of policy – including mapping the Soviet Union for nuclear strike planning, the economic containment of the USSR, as well as China and North Korea during the Korean War, and in monitoring the production of Soviet bombers and missiles – before becoming a central component of the new DIS.
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MacKinnon, Robert James. "Affective geographies of models and modelling." Thesis, Aberystwyth University, 2016. http://hdl.handle.net/2160/3bddf5c3-52b9-428b-ba10-4b0384b4b6b2.
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With reference to three contexts of models and modelling practice (hydraulic models of environmental systems, model railways and miniature wargaming), this thesis asserts the importance of geography in understanding what models can be, what and how they can do, and how and why models may be made and engaged with. The thesis traces spatialities of models and modelling via conceptions of affect, emotion and feeling, alongside abstraction, the miniature and mimesis, in order to highlight how space is central to lived and embodied engagements with models and modelling. This thesis makes several contributions. Firstly, this thesis gives shape to five key interrelated ‘geographies of models and modelling’, these are; one: models and modelling can generate space-times, and in so doing, produce affective engagements with those space-times. Two: models, modelling and material and embodied affects can shape how spaces (including models) may be constituted, affected, encountered and engaged with. Three: practice can inform modelling as a representational practice and be important to models as representations. Four: modelling as a mimetic practice which, as well as model and modelling engagements, can involve embodied relations whether with places, landscapes, environments, events, people, materials, objects (including models), and temporalities of pasts, presents and futures. Finally, five: model and modelling engagements can be involved with the miniature and an ‘affirmative critique’ of abstraction. Through these geographies and the theoretical underpinnings of this thesis, the second core contribution: six broad lessons about models and modelling. These are; one: models and modelling and the absence and presence of possession. Two: modelling as a negotiated practice. Three: modelling as ‘drawing out elements of the world’. Four: models and modelling as connecting us with the world. Five: models and modelling and human and non-human relations. Finally, six: models and modelling and the more-than-representational.
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Beattie, Melissa. "Travelling Torchwood(s) : national and transnational identities, glocalisation and the pseudo-reflexive audience." Thesis, Aberystwyth University, 2017. http://hdl.handle.net/2160/d019a8ca-5018-4cb3-ba9f-47304fa78910.
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Telefantasy series Torchwood (2006-2011, multiple production partners) was industrially and paratextually positioned as being Welsh, regardless of its frequent status as an international coproduction. When, for series four, the production (and diegesis) moved primarily to the US as a coproduction between BBC Worldwide and American premium cable broadcaster Starz, fan response was negative from the announcement, with the series being termed 'Americanised' in popular and academic discourse (e.g., Porter 2012, Derhy 2013). This study interrogates these assumptions via textual, industrial/contextual and audience analysis and finds that, in part due to the competing public service and commercial remits of the BBC, Torchwood was a glocalised text from the beginning, despite its positioning as Welsh, which then became glocalised again in series four. This 'second order of glocalisation,' as I term it, has not previously been explored in depth within TV Studies. It leads to a disjuncture between the national 'imaginary' (Tulloch 1995: 151, cf Weissmann 2012)-- as expressed by the text and interpreted by the (fan) audience. The study also develops the concept of a banal diegetic nationalism, drawn from Billig (1995) and adapted to television aesthetics; this includes elements of the mise-en-scène with a special focus on costume drawn from interviews with both costumers for the series. The Bourdieuian concepts of fan and national cultural capitals are also explored in-depth; their interplay creates and impacts a number of potential readings. In addition, by having conducted 42 semi-structured interviews and four focus groups (totalling 16 further participants), this study qualitatively investigates various readings produced by audience members in the US, UK and Canada, as well as transnational viewers who are long-term residents of one of those nations. The study finds that the audience is pseudo-reflexive (cf. Sender 2012) when it comes to interpretation; though all express an awareness and acceptance that national identity is constructed and fluid, they still express an underlying essentialism when discussing national identity in the context of the series. This broadly agrees with Tulloch (1995) and Weissmann (2012) who both note the inflexibility of audience readings with regard to television and national identity (and their attendant connotations) whilst also helping to account for the lack of reading the initial series text as glocalised. The focus upon fan and national cultural capitals also allows for a discussion of performativity in the context of national identity. My work innovatively extends debates surrounding transnational TV drama into audience studies, at the same time demonstrating the ongoing importance of carrying out critical readings of fan interpretations.
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Modh, Sandra Violeta. "Lamaholot of East Flores : a study of a boundary community." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:b7693f46-3a18-4b1a-ba96-0f17e91f0282.
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Lamaholot is a population found on Flores and in the Solor Archipelago of Eastern Indonesia. The population is village-based and divided into patrilineal descent groups. Marriage is coupled with bridewealth and follows a pattern of asymmetric marriage alliance between descent groups. This thesis shows that a small group of Lamaholot in the administrative regency of East Flores shares certain traditions with a neighbouring population called Ata Tana ‘Ai. Ata Tana ‘Ai are a sub-group of the Sikka population in the administrative regency of Sikka. Descent group among Ata Tana ‘Ai are matrilineal and households were traditionally based in scattered gardens. Marriage is not coupled with bridewealth and instances of asymmetric marriage alliance between descent groups are here a consequence rather than a cause of marriage. The current fieldsite seems to have been part of the ceremonial system of Ata Tana ‘Ai and also to have shared a tradition of dispersed settlement in the gardens. The descent groups might initially have been matrilineal, but in the recent past there was also a habit of dividing children between the parental descent groups. Recent traditions of dividing children can be found throughout central-east Flores, but seemingly not to same extent as at the fieldsite. The payment of elephant’s tusks was a central feature in the acquisition of group members at the fieldsite and could be paid by both men and women. These payments were not necessarily tied to marriage and did not serve as bridewealth. In the last century outer social factors, such as the Catholic mission and the creation of the Dutch colonial state, have resulted in that many of the traditional practices at the fieldsite have been replaced with traditions from Lamaholot elsewhere. The residence pattern is now village-based, but gardens retain a central social and ritual position. The role of the elephant’s tusks has taken different expressions throughout this period of social change, and alongside the changing role of tusks, the traditional social and material authority of women at the fieldsite has declined, whereas that of men has increased. This thesis examines the current and the traditional practices in and around the fieldsite, and focuses on local definitions of descent group, kinship, and inheritance, looking at both biological and social perspectives.
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Roberts, Thomas C. "Duchenne muscular dystrophy : RNA-based therapeutics and microRNA biology." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:f53ea1f3-92db-4f90-ba95-01f2a56eae8f.
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Duchenne muscular dystrophy (DMD) is a progressive muscle wasting disorder caused by absence of functional dystrophin protein. This thesis describes investigations into the role of small non-coding RNAs in both DMD pathology, and as potential therapeutic molecules. MicroRNAs (miRNAs) are a class of small RNAs that regulate gene expression and are implicated in wide-ranging cellular processes and pathological conditions. This study has compared differential miRNA expression in proximal and distal limb muscles, diaphragm, heart and serum in the mdx dystrophic mouse model relative to wild-type controls. Global transcriptome analysis revealed muscle-specific patterns of differential miRNA expression as well as commonalities between tissues, including previously identified dystromirs. miR-1, miR-133a and miR-206 were found to be highly abundant in mdx serum, suggesting that these miRNAs are promising disease biomarkers. Indeed, the relative serum levels of these miRNAs were normalised in response to peptide-PMO mediated dystrophin restoration therapy. This study has revealed further complexity in the miRNA transcriptome of the mdx mouse, an understanding of which will be valuable for the development of novel DMD therapeutics and for monitoring their efficacy. Myostatin is a secreted growth factor that negatively regulates muscle mass and is therefore a potential pharmacological target for the treatment of muscle wasting disorders such as DMD. This study describes a novel myostatin inhibition approach in which small interfering RNAs (siRNAs) complementary to a promoter-associated transcript induce transcriptional gene silencing (TGS) in cultured myotubes. Silencing was sensitive to treatment with the histone deacetylase inhibitor Trichostatin A, and the silent state chromatin mark H3K9me2 was enriched at the myostatin promoter following siRNA transfection, suggesting epigenetic remodelling underlies the silencing effect. These observations suggest that long-term epigenetic silencing may be feasible for myostatin and that TGS is a promising novel therapeutic strategy for the treatment of muscle wasting disorders. The work in this thesis therefore demonstrates the potential of small RNAs as therapeutic agents and as disease biomarkers in the context of DMD.
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Ahmed, Farrah. "Religious autonomy and the personal law system." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:e8d532c3-be53-4823-ba9d-bb78a9aaefcc.
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This thesis examines the Indian system of personal laws (‘the PLS’), under which the state applies a version of religious doctrine to the family matters of citizens whom it identifies as belonging to different religious groups. There has been a lengthy and persistent debate over the PLS, particularly in relation to its discriminatory effects upon women. However, another problem with the PLS has been little commented-upon. Supporters of the PLS emphasise its positive impact on religious freedom to such an extent that there is a pervasive assumption that the PLS is, indeed, good for religious freedom. But there has been surprisingly little critical assessment of the truth of this claim in either academic or political debates. This thesis, a work of applied normative legal theory, attempts to fill this important gap in the literature on the PLS. The thesis addresses the question of how the PLS affects one conception of religious freedom, namely religious autonomy. Its principal findings are that the PLS interferes with the religious autonomy of those subject to it by affecting their religious options (by interfering with their freedom from religion and their freedom to practice religion) and by harming their self-respect (by discriminating on the grounds of sex and religion, and by misrecognising their religious identities). Furthermore, the thesis finds that the PLS cannot be defended in the name of religious autonomy based on the possibility of exit from the system, the advantage of having the ‘option of personal law’, the power it gives people to bind their future selves, the expressive potential of the personal laws, the contribution it makes to membership in a religious community, the contribution it makes to religious group autonomy, or the recognition or validation it provides for religious identities. These conclusions imply that concerns relating to religious autonomy constitute an important set of objections to the PLS. The thesis then considers several reform proposals, including certain modifications of the PLS, a move towards a millet system, ‘internal’ reform of individual personal laws and the introduction of a Uniform Civil Code. It particularly focusses on one reform possibility – religious alternative dispute resolution – which has not been considered closely in the Indian context.
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Razak, Huzaifah Haritsah Abdul. "Wetting behaviour of colloid-polymer mixtures in confinement." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:e75a8463-fe02-46f3-ba95-7d7b40c955cb.
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We study the wetting behaviour of phase-separating colloid-polymer mixtures in confinement. The phase separation is due to the depletion attraction between the colloids mediated by the polymers and bears similarities to ordinary phase separation of oil and water. We use laser scanning confocal microscopy to investigate the behaviour of our colloidal mixture in the vicinity of different substrates, which serve as the confining walls. The glass walls used are chemically modified with two types of polymer, polyacrylamide and chitosan, and we also use clean glass as a reference. We find that the polymer grafting of the surfaces has a pronounced effect on the wetting behaviour. Here, we observe the formation of colloidal liquid droplets, which implies that the coated walls are partially wet. This geometry allows for the determination of the contact angle. The shape of the droplet is theoretically described by the interplay between gravity and interfacial curvature, with the contact angle entering as a boundary condition. The reconstructed interfacial drop profiles are then fitted to the theoretical model to quantitatively study its variation as a function of colloid-polymer state point, properties of the confining wall, and droplet size. We also visually observe Cahn's wetting transition from partial to complete wetting in three series of state points as we move closer to the binodal. This enables us to estimate the wetting transition line in our phase diagram. In addition, we disperse polyacrylamide-coated silica beads into our colloid-polymer mixtures to observe the wetting effects near curved surfaces. We generate theoretical plots based on the conditions of mechanical equilibrium, and compare to the experiments. Our studies shine light on partial wetting phenomena for systems where the interfacial roughness is comparable to the other relevant lengthscales in the system, such as the droplet size or the curvature of the surface.
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Scaber, Jakub. "The pathophysiological role of TDP-43 in amyotrophic lateral sclerosis due to C9orf72 mutations." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:c5dd8dcf-c3e0-4ff7-ba9d-bfd3cb9914e8.
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Amyotrophic Lateral Sclerosis (ALS) is a neurodegenerative condition that affects corticospinal and spinal motor neurons and leads to death within 30 months of symptom onset in half of all cases. It remains incurable and treatment is supportive. The genetic and molecular understanding of ALS has gone through a rapid expansion in recent years, notably with the discoveries of TDP-43, a heterogeneous ribonucleoprotein as a major component of neuronal inclusions in ALS, as well as the discovery of the C9orf72 hexanucleotide expansion as the most common genetic cause of this disease. This first part of this thesis addresses the question of which of the various pathological hallmarks of the C9orf72 Hexanucleotide Repeat Expansion (HRE) in autopsy material correlates best with the clinical presentation. The main finding is that TDP-43 distribution, rather than C9orf72 RNA foci or dipeptide aggregation in the brain, corresponds best with the areas relevant to the clinical subtype of ALS-FTD. Subsequently the role of TDP-43 was investigated in induced pluripotent stem cell derived motor neurons, and no evidence of the hallmarks of TDP-43 dysfunction, were seen in this model of the disease. No mislocalisation is found on immunofluorescence, and biochemical analysis shows no differences in insoluble species between the patient and control cell lines. In the final section, RNA sequencing was used to study the transcriptome of a BAC transgenic mouse carrying a human M337V transgene expressed at low levels, to identify early presymptomatic differences in gene expression. Interestingly, no changes were found in genes known to be associated with ALS through mutations, and the constitutive nuclear functions of TDP-43 in the regulation of splicing was maintained, prior to the emergence of a clinical phenotype in the mouse. This favours a gain of function mechanism for TDP-43 mutations in ALS.
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Man, James K. C. "Characterisation of a novel animal model for obsessive-compulsive disorder." Thesis, University of Bristol, 2005. http://hdl.handle.net/1983/6cec00ce-f3c1-4d07-ba98-54c137b7524a.
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Dodds, Klaus-John. "Critical geopolitics and the writing of foreign policy." Thesis, University of Bristol, 1993. http://hdl.handle.net/1983/54c2c69d-717d-4def-ba92-eff80f4d13c6.
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Dobnik, Simon. "Teaching mobile robots to use spatial words." Thesis, University of Oxford, 2009. http://ora.ox.ac.uk/objects/uuid:d3e8d606-212b-4a8e-ba9b-9c59cfd3f485.
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The meaning of spatial words can only be evaluated by establishing a reference to the properties of the environment in which the word is used. For example, in order to evaluate what is to the left of something or how fast is fast in a given context, we need to evaluate properties such as the position of objects in the scene, their typical function and behaviour, the size of the scene and the perspective from which the scene is viewed. Rather than encoding the semantic rules that define spatial expressions by hand, we developed a system where such rules are learned from descriptions produced by human commentators and information that a mobile robot has about itself and its environment. We concentrate on two scenarios and words that are used in them. In the first scenario, the robot is moving in an enclosed space and the descriptions refer to its motion ('You're going forward slowly' and 'Now you're turning right'). In the second scenario, the robot is static in an enclosed space which contains real-size objects such as desks, chairs and walls. Here we are primarily interested in prepositional phrases that describe relationships between objects ('The chair is to the left of you' and 'The table is further away than the chair'). The perspective can be varied by changing the location of the robot. Following the learning stage, which is performed offline, the system is able to use this domain specific knowledge to generate new descriptions in new environments or to 'understand' these expressions by providing feedback to the user, either linguistically or by performing motion actions. If a robot can be taught to 'understand' and use such expressions in a manner that would seem natural to a human observer, then we can be reasonably sure that we have captured at least something important about their semantics. Two kinds of evaluation were performed. First, the performance of machine learning classifiers was evaluated on independent test sets using 10-fold cross-validation. A comparison of classifier performance (in regard to their accuracy, the Kappa coefficient (κ), ROC and Precision-Recall graphs) is made between (a) the machine learning algorithms used to build them, (b) conditions under which the learning datasets were created and (c) the method by which data was structured into examples or instances for learning. Second, with some additional knowledge required to build a simple dialogue interface, the classifiers were tested live against human evaluators in a new environment. The results show that the system is able to learn semantics of spatial expressions from low level robotic data. For example, a group of human evaluators judged that the live system generated a correct description of motion in 93.47% of cases (the figure is averaged over four categories) and that it generated the correct description of object relation in 59.28% of cases.
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Lang, Tamara Jane. "Cognitive bias modification in the context of depression : interpretation bias and mental imagery." Thesis, University of Oxford, 2009. https://ora.ox.ac.uk/objects/uuid:23e218bf-c546-4b84-ba09-1545a3d538a4.
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The aim of this thesis was to develop a positive Cognitive Bias Modification (CBM) technique using imagery in the context of depressed mood. CBM targets biases associated with emotional disorders. CBM modifying interpretation bias (CBM-I) has been investigated for anxiety, but not depression. Whilst many cognitive processes contribute to depression, the current focus was on mental imagery and interpretation bias. In a series of six studies a positive, imagery-oriented CBM-I was developed, culminating in a final test in a clinically depressed population. Prior research had demonstrated that for positive CBM-I, a verbal rather than imagery condition was not only less effective at promoting positive mood, but led to mood deterioration. Experiment 1 investigated what aspect of verbal processing might be responsible for the paradoxical increase in negative emotion. Results suggested that unfavourable comparisons between the self and the positive CBM-I material was driving the increased negativity. Experiment 2 investigated whether making such comparisons in an imagery mode would yield similar effects and whether field perspective imagery instructions would enhance positive CBM-I. Results indicated that optimal instructions for CBM-I should include field perspective imagery whilst discouraging comparative processing. Studies 3a and 3b investigated the relationship between interpretation bias, mental imagery and depressive symptoms in a large sample. Interpretation bias discriminated between low and high dysphoric participants, who had a greater frequency of negative intrusive images. To target negative intrusive images, a new CBM-I technique was developed in Study 4 and Experiment 5 - "CBM of appraisals". Compared to negative CBM of appraisals training, positive training led to fewer intrusive memories and less intrusive symptomatology concerning a depressive film after one week. Finally in Experiment 6, a multi-component CBM-I package (including auditory CBM-I from Experiments 1 and 2; CBM of appraisals from Study 4 and Experiment 5; plus a picture-word technique) was tested in 24 participants with clinical depression. Positive compared to neutral multi-component CBM-I led to improvements in interpretation bias, appraisal bias, depressive and intrusive symptoms. This suggests the potential clinical benefit of a multi-component positive imagery-oriented CBM-I package.
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Davies, A. C. L. "Accountability : a public law analysis of National Health Service contracts." Thesis, University of Oxford, 1999. https://ora.ox.ac.uk/objects/uuid:7fa277f4-ba95-46e6-bd82-81ab2236acd5.
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The thesis takes as its subject the concept of accountability. It examines the use made of the concept in the public law literature, and advances a novel analytical model of the individual accountability mechanism. The model identifies the essential features of that mechanism: setting standards against which an account can be judged; requiring the person being called to account to explain and justify his or her actions; judging the account rendered against the standards set; and responding to the account rendered, where appropriate, with enforcement measures. This analytical approach provides a way of examining, in detail, an individual accountability mechanism, and identifying the main practical problems faced by the parties to it. The approach is applied to an empirical case study of National Health Service (NHS) contracts. (The fieldwork involved an examination of contractual relationships between purchasers (Health Authorities and GP fundholders) and providers (NHS Trusts) in three sample areas, using document analysis, interviews and observation.) The study's main findings fall into three groups. Firstly, purchasers were subject to various pressures and constraints (of time and resources, for example) which affected their actions in calling providers to account. Secondly, the study uncovered some of the complexities of the relationship between the parties to the accountability process. Analytical models of the accountability relationship were developed in order to classify different types of relationship according to the parties' behaviour and their degree of mutual trust. Thirdly, the study examined whether purchasers, as callers to account, could render the accountability process effective. For various reasons, purchasers often lacked the authority to set and enforce the standards they required. The model of the accountability mechanism developed in the thesis also has evaluative potential. Drawing on the public law literature as well as the empirical data, a notion of the good accountability process is evolved. This includes, for example, requirements of maximising the accountability achieved within available resources, maintaining good relationships by using fair procedures, and finding ways of making the whole process effective. Some of these principles may be of more general application to other accountability processes. Possible generalisations are explored, particularly the contribution of the thesis to the development of an explicitly public law concept of contract.
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Giles, Rohini. "Jupiter's tropospheric composition and cloud structure from 5-μm spectroscopy." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:04619240-ba40-4ee2-afcc-7f911f364d05.
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This thesis uses infrared observations from spacecraft and ground-based telescopes to investigate the composition and cloud structure of the jovian atmosphere. It focuses on a single spectral region, known as the 5-μm window, where Jupiter's upper atmosphere becomes optically thin. This allows us to probe down beneath the planet's thick cloud decks to the 4{8 bar region in the middle troposphere. Two different data sources are combined to build up a three-dimensional picture of Jupiter's troposphere. The first dataset is from the Cassini VIMS instrument, and was taken during the 2000-2001 Jupiter yby. These observations cover a wide spectral range, provide global coverage and include both the nightside and the dayside of the planet, making them well suited to studying clouds. The VIMS spectra can be modelled using a single tropospheric cloud deck, subject to the following constraints: (i) the cloud base is located at pressures of 1.2 bar or lower; (ii) the cloud particles are highly scattering; and (iii) the cloud is sufficiently spectrally at. The second dataset is from the CRIRES instrument at the Very Large Telescope in Chile. These observations have a very high spectral resolution, allowing the absorption lines of individual molecular species to be resolved. The CH3D line shape varies between belts and zones, which can be interpreted as variations in the opacity of a deep cloud, located at around 5 bar. There is also evidence for spatial variability in two disequilibrium species, AsH3 and PH3, both of which show an enhancement at high latitudes. This is in contrast to a third disequilibrium species, GeH4, which shows no evidence for spatial variability. The CRIRES dataset also includes several strong emission lines, which are identified as H3+, an auroral species in Jupiter's ionosphere. The strengths of these lines were measured in order to determine the ionospheric temperatures. The work in this thesis contributes to our understanding of the dynamical, chemical and cloud-forming processes shaping Jupiter's troposphere and provides a reference point for future work, including observations made by NASA's Juno mission.
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Patterson, Craig. "Galician cultural identity in the works of Ramón Otero Pedrayo (1888-1976)." Thesis, University of Oxford, 2002. http://ora.ox.ac.uk/objects/uuid:13caa1aa-e825-4e28-bac0-c4fa3e131cdb.
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In the 1920's, the grouping of Galician intellectuals known as the Xeración Nós began, through their wide-ranging literary output and more specifically political activities, to articulate and reinterpret essential notions of Galician cultural identity after several centuries of cultural repression and centralisation. This thesis examines both the nexus of inherited positions informing this cultural recovery, and its original reformulation, through the works of the most prominent intellectual of the Xeración Nós, Ramón Otero Pedrayo (1888 1976). Otero was an important figure in Galician intellectual and cultural life over the larger part of the twentieth century, especially when expression of Galician distinctiveness, whether political or cultural, was severely limited and largely discouraged by the Franco regime. He is particularly deserving of an in-depth study, especially since this theme so intrinsically associated with him has not yet been written upon from a perspective of cultural history. In order to provide as accurate an analysis as possible of Otero's conception of Galician reality and the developmental nature of his ideas, I have consulted a large number of texts, ranging from brief journalistic sketches to dense biographical tomes. In particular, I focus on the large body of essays written by Otero such as the Ensaio histórico sobre a cultura galega (1932) and the more imaginative configuration of Galician identity contained in the trilogy of novels Os camiños da vida (1928), Arredor de si (1930) and Devalar (1935). This allows for an analysis of the writer's perspective on the essential bases of Galician culture via the recuperation through literature (most notably the influence of the broad cultural revival initiated in the 1860's, or Rexurdimento, and the influence of historical and cultural co-ordinates ultimately derived from Romantic thought). Crucial in shaping Otero's definitive vision is an eclectic array of references from cultural history both ancient and modern, ideological import through the Celtic ideal, and contemporary social issues (such as the political climate of the Second Republic). To be seen firmly within the parameters of an intellectual history, this thesis has as its objective an explanation how these intrinsic and extrinsic sources of influence condition Otero's evaluation of Galician distinctiveness, and what that quality actually embodies, within the context of the cultural activity prevalent in Galicia from 1918 to 1936 and beyond.
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Plain, Fiona. "Characterisation of the cell-surface localised palmitoyl acyl transferase, DHHC5." Thesis, University of Dundee, 2018. https://discovery.dundee.ac.uk/en/studentTheses/04ab7344-ba00-49bb-8eb8-5c8b70e18559.
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S-Palmitoylation is the reversible addition of 16-carbon fatty acids onto cysteine residues of proteins. The functional consequences of palmitoylation are diverse and it has been demonstrated to play a critical role in several physiological and disease pathways. DHHC palmitoyl acyl transferase (DHHC-PAT) enzymes are responsible for catalysing the addition of acyl groups onto cysteine residues and there are 23 human DHHC-PAT isoforms. All isoforms share a conserved DHHC catalytic motif and they display heterogeneity in their N- and C- termini. This coupled with differing sub-cellular localisations is thought to be the basis of substrate specificity. DHHC5 is a cell surface localised DHHC-PAT which has a characteristic, long cytoplasmic C-tail which is responsible for substrate recruitment. DHHC5 has an established role in hippocampal learning and memory formation. It is also known to palmitoylate phospholemman (PLM), thereby regulating cardiac sodium pump activity. However, the regulatory mechanisms governing substrate recruitment by DHHC5 are not understood and it is thought that there are more, currently unidentified DHHC5 substrates. The aims of this project were to i) identify the PLM binding site on the DHHC5 C-tail and investigate how PLM recruitment to DHHC5 is regulated, and ii) develop and use a peptide-based array to identify novel DHHC5 substrates. A small peptide-based array identified a PLM binding site on the DHHC5 C-tail, positioned just after the final transmembrane domain. Further interrogation of this region revealed that DHHC5 is palmitoylated on its C-tail at a di-cysteine motif situated close to the PLM binding site at residues 236/237. Over-expression of DHHC20 increased palmitoylation of DHHC5 in HEK293 cells, but not when the di-cysteine motif was mutated. DHHC20 overexpression in HEK293 cells also increased coimmunoprecipitation of PLM with DHHC5 and again the di-cysteine motif was required for this. Therefore, it was concluded that DHHC20 palmitoylates DHHC5 at a di-cysteine motif on its C-tail, and regulates recruitment of PLM to DHHC5. A peptide-based array covering the entire DHHC5 C-tail was developed and used to purify interacting proteins from rat heart and mouse cerebellum tissue lysates. Mass spectrometry (LC-MS/MS) was used to identify DHHC5 interacting proteins and a stringent filtering process identified high-confidence putative DHHC5 substrates. Several candidate proteins identified by LC-MS/MS were tested using a validation protocol, resulting in the identification of two novel DHHC5 substrates; FAT/CD36 and Gai2. Palmitoylation of GFP-tagged FAT/CD36 and Gai2 was reduced in DHHC5 KO cells compared to HEK293 cells. This was rescued by overexpression of DHHC5 but not DHHC17 in DHHC5 KO cells, confirming these as DHHC5 substrates. FAT/CD36 is responsible for the majority of long chain fatty acid uptake in several tissues and has particular importance in the heart. Further investigation of FAT/CD36 as a DHHC5 substrate revealed that palmitoylation by DHHC5 does not contribute to cell surface localisation of FAT/CD36. FAT/CD36 activity was measured indirectly by using Oil Red-O staining to determine the intracellular lipid content. There was significantly less Oil Red-O staining in DHHC5 KO cells overexpressing FAT/CD36 compared to HEK 293 cells and this was rescued by overexpression of DHHC5 but not DHHC17 in the KO cells. Therefore, it was concluded that palmitoylation of FAT/CD36 by DHHC5 increases FAT/CD36 mediated fatty acid uptake. Furthermore, insulin has been shown to increase DHHC5 C-tail palmitoylation in adult rat ventricular myocytes. This suggests that insulin may regulate palmitoylation of DHHC5 by DHHC20 and therefore recruitment of FAT/CD36 to DHHC5. However, the mechanism for this remains unclear. FAT/CD36 palmitoylation was elevated in a rat model of type 2 diabetes, which may contribute to increased fatty acid uptake and lipotoxicity in the diabetic heart. Overall, this project has identified novel regulatory mechanisms governing substrate recruitment by DHHC5. Furthermore, two novel DHHC5 substrates have been identified by a peptide-based array of the DHHC5 C-tail. A novel insulin-DHHC signalling axis has been identified which may be responsible for regulating FAT/CD36 palmitoylation and therefore fatty acid uptake.
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Andrew, Morag Jane. "Neurodevelopmental and visual outcomes of infants at risk of neurodevelopmental disability following dietary supplementation in infancy." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:2c4a24e3-4924-4085-bad0-fb054622cb7f.
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Background: Docosahexaenoic acid (DHA), choline and uridine-5-monophosphate (UMP) are important brain nutrients which form phosphatidylcholine, the most abundant brain membrane phospholipid. DHA, choline and UMP supplementation increases rodent brain phospholipids, synaptic components, functional brain connectivity and cognitive performance. This novel pilot study supplemented infants at risk of neurological impairment (ARNI) with a nutrient combination containing these neurotrophic compounds. Aims: 1) In a double blind randomised control trial (RCT), investigate if intake of a specific nutrient combination improves neurodevelopmental and visual outcome in infants ARNI. 2) Using novel measures of cortical visual function, investigate the effect of perinatal brain injury severity, gestational age at birth and sex upon visuocognitive development in infants at risk of neurodevelopmental impairment. Method: Recruitment was from UK neonatal units. Eligibility: ≤ 31 weeks, weight < 9th percentile; < 31 weeks with ≥ Grade II intraventricular haemorrhage (IVH) or preterm white matter injury (PWMI); 31-40 weeks with ≥ Grade II IVH or PWMI, ≥ Sarnat Grade II HIE or defined brain MRI abnormalities. Stratification was by sex, gestation and brain injury severity. Randomised infants received neurotrophic supplementation or placebo, for 2 years. Primary outcome was Bayley Scales of Infant Development III (BSID III) composite cognitive score (CCS) after 2 years. Secondary outcomes included BSID III composite language score (CLS) and BSID III composite motor score (CMS). Cortical visual measures were pattern reversal visual event related potential (PR-VERP) latency (transient and calculated), orientation reversal visual event related potentials (OR-VERP), and the Fixation Shift test (FS). Functional behavioural vision was assessed using the Atkinson Battery of Child Development for Examining Functional Vision (ABCDEFV). Local Ethics Committee approval was granted. Results: 62 neonates were recruited. After 2 years, mean CCS in the intervention group was 87.7 (SD 20.4) and 81.6 (SD 18.5) in the placebo group (mean difference = 2.28, p=0.13; -0.2, 18.2). Mean CLS in the intervention group was 91.5 (SD 20.1) and 83.2 (SD 19.6) in the placebo group (mean difference = 2.74, p=0.1; -2.4, 18.3). CMS was similar in both groups. In relation to trial visual outcome measures, more infants in the placebo group gave a statistically significant OR-VERP response than in the intervention group (p=0.03). There were no statistically significant differences between the placebo and intervention on any other trial visual outcome measure. Cohort analyses indicate that transient PR-VERP latency is prolonged in children at risk of neurodevelopmental disability compared to typically developing infants (mean difference = -23.3, p=0.015, 95% CI -42.10 - -4.54). Calculated PR-VERP latency is prolonged to an even greater extent in children at risk of neurodevelopmental disability compared to typically developing infants (mean difference -148.6, p=0.000, 95% CI -179.7- -117.43), and remains prolonged across the age range tested. Conclusions: 1) The difference in CCS and CLS between intervention and placebo groups represents a clinically significant effect size. Use of neurotrophic micronutrient supplementation in infants ARNI warrants exploration in a large multicentre RCT. 2) Calculated PR-VERP latency may be a more appropriate outcome measure of cortical visual function than transient PR-VERP latency in infants at risk of neurodevelopmental disability.
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Pignot, Matthieu. "The catechumenate in late antique Africa : Augustine of Hippo, his contemporaries and early reception (ca. 360-530 AD)." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:52282a58-7163-40a2-ba9b-632d582debeb.
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In the late antique West, every individual becoming Christian first entered the community as a catechumen (catechumenus). Many spent several years in this status called the catechumenate, only ending with baptism and the acquisition of the membership of the faithful (fideles). This thesis considers the catechumenate not only as an initiation but as a peculiar way of being Christian. It demonstrates the fluid nature of Christian membership and shows how clerics strove to develop their authority over catechumens to build a cohesive community in a context of rivalry between churches and polemical controversies. The catechumenate both enabled converts to adhere progressively to the community and constituted an opportunity for clerics to set a standard path of progression, enforce discipline and define what it meant to be a Christian. This thesis opens up new avenues to study the process of Christianisation by stressing the continuous significance of the catechumenate for the formation of Christian communities in late antiquity. After an introduction, Chapter Two focuses on Augustine's recollections of his time as a catechumen. Chapter Three looks at Augustine to investigate more broadly the practices of catechumeni, shedding light on the pervasive polemical context in which they are discussed. Chapter Four provides case studies on the cross put on the forehead to manifest Christian membership and the treatise De fide et operibus, exploring how Augustine aimed at shaping practices and ideas. Chapter Five investigates contemporary evidence: first an African canon regulating the ritual participation of catechumeni, then sermons describing unique rituals of the baptismal preparation and demonstrating that practices often varied locally. Chapter Six compares the sixth-century letter exchanges between Ferrandus and Fulgentius with John the Deacon's letter to Senarius, showing the enduring importance of the catechumenate in the West and the creative reception of earlier African sources addressing recurrent pastoral problems.
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Virk, Amrit Kaur. "Expanding health care services for poor populations in developing countries : exploring India's RSBY national health insurance programme for low-income groups." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:3e65305c-ba60-408a-8c0a-8957767f6596.
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Health is deemed central to a nation’s development. Accordingly, health care reform and expansion are key policy priorities in developing countries. Many such nations are now testing various methods of funding and delivering health care to local disadvantaged populations. Similarly, India launched the Rashtriya Swasthya Bima Yojana (RSBY) national health insurance programme for low-income groups in 2008. The RSBY intends preventing catastrophic health-related expenditure by improving recipients’ access to hospital-based care. This thesis is an in-depth qualitative evaluation of the RSBY in Delhi state. It examines the RSBY’s effectiveness in fulfilling its goals and meeting local health care needs. Walt and Gilson’s (1994) actors-content-process-context model informs the research design and an actor-centred “responsive” (Stake 1975) or “constructivist” approach guides data analysis. Three research questions are examined: (i). Why was a health insurance programme launched and why now? Why was this model favoured over alternate methods of service expansion? (ii). Is the RSBY delivered as intended? If not, why? (iii) How does the RSBY affect patients’ access to services? The findings are based on documentary sources, observation of implementation sites and activities and 164 semi-structured interviews with RSBY policymakers, insurers, NGOs, doctors, and patients. The results show improved access to curative and surgical care for RSBY patients. However, RSBY’s focus on hospitalisation and omission of primary and outpatient services had undesired negative effects. The lack of ambulatory facilities led RSBY patients to self-medicate or use dubious quality informal providers. By only allowing inpatient care, the RSBY also seemingly encouraged the substitution of outpatient care with costlier hospitalisations. In effect, the RSBY’s design contributed to cost increases and poor patient outcomes. While more funds and human resources were needed to improve RSBY implementation, the performance of frontline agencies could potentially improve through more stable, longer-term contracts. Similarly, modifying RSBY’s monetary incentives for doctors may lead to better service delivery by them. By evaluating the RSBY’s strong points and shortcomings, this thesis provides key lessons on strengthening policy design and health service delivery in developing countries. Thereby, it makes a broader contribution to understanding the determinants of successful policymaking.
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Otto, Ernst. "Development of superconducting bolometer device technology for millimeter-wave cosmology instruments." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:30a1103a-ea7a-4b08-ba92-665cbd9740e0.
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The Cold-Electron Bolometer (CEB) is a sensitive detector of millimeter-wave radiation, in which tunnel junctions are used as temperature sensors of a nanoscale normal metal strip absorber. The absorber is fed by an antenna via two Superconductor-Insulator-Normal metal (SIN) tunnel junctions, fabricated at both ends of the absorber. Incoming photons excite electrons, heating the whole electron system. The incoming RF power is determined by measuring the tunneling current through the SIN junctions. Since electrons at highest energy levels escape the absorber through the tunnel junctions, it causes cooling of the absorber. This electron cooling provides electro-thermal feedback that makes the saturation power of a CEB well above that of other types of millimeter-wave receivers. The key features of CEB detectors are high sensitivity, large dynamic range, fast response, easy integration in arrays on planar substrates, and simple readout. The high dynamic range allows the detector to operate under relatively high background levels. In this thesis, we present the development and successful operation of CEB, focusing on the fabrication technology and different implementations of the CEB for efficient detection of electromagnetic signals. We present the CEB detector integrated across a unilateral finline deposited on a planar substrate. We have measured the finline-integrated CEB performance at 280-315 mK using a calibrated black-body source mounted inside the cryostat. The results have demonstrated strong response to the incoming RF power and reasonable sensitivity. We also present CEB devices fabricated with advanced technologies and integrated in log-periodic, double-dipole and cross-slot antennas. The measured CEB performance satisfied the requirements of the balloon-borne experiment BOOMERANG and could be considered for future balloon-borne and ground-based instruments. In this thesis we also investigated a planar phase switch integrated in a back-to-back finline for modulating the polarization of weak electromagnetic signals. We examine the switching characteristics and demonstrate that the switching speed of the device is well above the speed required for phase modulation in astronomical instruments. We also investigated the combination of a detector and a superconducting phase switch for modulating the polarization of electromagnetic radiation.
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Constantin, Andrei. "Heterotic string models on smooth Calabi-Yau threefolds." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:30be3aee-ba9b-4417-9b00-ee26a6bd67c5.
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This thesis contributes with a number of topics to the subject of string compactifications, especially in the instance of the E8 × E8 heterotic string theory compactified on smooth Calabi-Yau threefolds. In the first half of the work, I discuss the Hodge plot associated with Calabi-Yau threefolds that are hypersurfaces in toric varieties. The intricate structure of this plot is explained by the existence of certain webs of elliptic-K3 fibrations, whose mirror images are also elliptic-K3 fibrations. Such manifolds arise from reflexive polytopes that can be cut into two parts along slices corresponding to the K3 fiber. Any two half-polytopes over a given slice can be combined into a reflexive polytope. This fact, together with a remarkable relation on the additivity of Hodge numbers, give to the Hodge plot the appearance of a fractal. Moving on, I discuss a different type of web of manifolds, by looking at smooth Z3-quotients of Calabi-Yau three-folds realised as complete intersections in products of projective spaces. Non-simply connected Calabi-Yau three-folds provide an essential ingredient in heterotic string compactifications. Such manifolds are rare in the classical constructions, but they can be obtained as quotients of homotopically trivial Calabi-Yau three-folds by free actions of finite groups. Many of these quotients are connected by conifold transitions. In the second half of the work, I explore an algorithmic approach to constructing E8 × E8 heterotic compactifications using holomorphic and poly-stable sums of line bundles over complete intersection Calabi-Yau three-folds that admit freely acting discrete symmetries. Such Abelian bundles lead to N = 1 supersymmetric GUT theories with gauge group SU(5) × U(4) and matter fields in the 10, ⁻10, ⁻5, 5 and 1 representations of SU(5). The extra U(1) symmetries are generically Green-Schwarz anomalous and, as such, they survive in the low energy theory only as global symmetries. These, in turn, constrain the low energy theory and in many cases forbid the existence of undesired operators, such as dimension four or five proton decay operators. The line bundle construction allows for a systematic computer search resulting in a plethora of models with the exact matter spectrum of the Minimally Supersymmetric Standard Model, one or more pairs of Higgs doublets and no exotic fields charged under the Standard Model group. In the last part of the thesis I focus on the case study of a Calabi-Yau hypersurface embedded in a product of four CP1 spaces, referred to as the tetraquadric manifold. I address the question of the finiteness of the class of consistent and physically viable line bundle models constructed on this manifold. Line bundle sums are part of a moduli space of non-Abelian bundles and they provide an accessible window into this moduli space. I explore the moduli space of heterotic compactifications on the tetraquadric hypersurface around a locus where the vector bundle splits as a direct sum of line bundles, using the monad construction. The monad construction provides a description of poly-stable S(U(4) × U(1))–bundles leading to GUT models with the correct field content in order to induce standard-like models. These deformations represent a class of consistent non-Abelian models that has co-dimension one in Kähler moduli space.
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Jackson, Williams Kelsey. "John Aubrey's antiquarian scholarship : a study in the seventeenth-century Republic of Letters." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:8e4dcd98-ba97-45d4-ac33-e64f8e0dd1e4.
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The writings of John Aubrey (1626-1697) cover a variety of subjects, including natural philosophy, mathematics, educational theory, biography, and magic, among others. His principal scholarly interest, however, was antiquarianism, the early modern discipline which embraced subjects such as archaeology, anthropology, and palaeography. This thesis is a study of Aubrey’s antiquarian writings within the context of the European Republic of Letters. It begins with a revisionary survey of antiquarianism in England, 1660-1720, and proceeds to map his personal contacts and library before studying each of his major antiquarian works in detail. Aubrey emerges from this as a product of his time, but somewhat unusual in his eclectic use of the antiquarian tradition and his blending of antiquarian and natural philosophical methodologies. He was receptive to the latest scholarship, regardless of its origin, and his antiquarian writings were never mere antiquarianism, but moved beyond technical scholarship to address wider issues concerning the origins of English culture, the evolution of religion, the antiquity of the earth, and the nature of human invention. Aubrey is now best known for his so-called Brief Lives, a series of biographies of contemporaries, and this thesis also includes a chapter studying the Lives as a form of antiquarianism. It argues that their keen observation and unconventional form are due to a mixture of antiquarian minuteness with traditions of Theophrastan character-writing and Tacitean historiography and that previous readings of them rely too heavily upon an outdated view of Aubrey as eccentric and peripheral to the larger intellectual movements of the century. This thesis concludes with a reassessment of Aubrey’s scholarship and an argument that the patterns revealed highlight the insufficiency of current theories of antiquarian development in the early modern period. It also argues for the “literary” quality of Aubrey’s work and emphasises the importance of reading his antiquarian texts within the context of early modern definitions of literature.
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Sadarangani, Manish. "Evaluation of a potential vaccine against hyperinvasive serogroup B Neisseria meningitidis by assessment of the effects of surface-expressed Opacity-associated proteins on the immune system." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:1c137f32-a37d-4cd4-bac0-4c0a927564bd.
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Neisseria meningitidis causes 500,000 cases of meningitis and septicaemia annually worldwide, with a mortality rate of approximately 10%. Most disease in developed countries is caused by serogroup B infection, against which there is no universal vaccine. Opa proteins are major meningococcal outer membrane proteins, and a limited number of Opa variants have been associated with hyperinvasive serogroup B meningococci, suggesting their use as a potential novel vaccine. Immunisation of mice with recombinant Opa elicited high levels of meningococcal-specific serum bactericidal antibody (SBA), demonstrating proof in principle of this approach. Opa proteins mediate bacterial adherence to host cells and modulate human cellular immunity, and there are conflicting data regarding their effects on CD4⁺ T cells. opa genes from N. meningitidis strain H44/76 were cloned into the plasmid vector pBluescript, disrupted using antibiotic resistance cassettes and transformed into H44/76 to sequentially disrupt the four opa genes. This produced a unique panel of 15 isogenic Opa-deficient strains, including an Opa-negative strain, which enabled investigation of the immunomodulatory role of surface-expressed Opa proteins. There was no consistent effect of Opa expressed on the surface of OMVs and inactivated bacteria on CD4⁺ T cells, with significant heterogeneity of responses between individuals. The rate of Opa phase variation was between 10-3 and 10-4, and increased 180-fold following transformation of bacteria with unrelated DNA. These data support further investigation of Opa as a potential meningococcal vaccine component, and highlight the importance of host and bacterial factors in the development of OMV vaccines.
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Alwarea, Amer. "Neighbourhood level master-planning : 'a strategic value-based decision-making perspective'." Thesis, University of Dundee, 2017. https://discovery.dundee.ac.uk/en/studentTheses/832e291e-1e01-41d7-ba95-883a8b945b25.
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The master-planning of large-scale neighbourhood development has become a central part of strategies to stimulate changes in local urban economy and property markets in Britain. However, the 2007-08 economic crisis severely disrupted urban development and created uncertainty affecting market conditions and the availability of investment, as well as policy change, and demographic and social change. Whilst researchers expounded on contemporary master-planning practice in the UK as too formal, inflexible, static, and misleadingly proximate to respond to these challenges, little is said about stakeholders’ susceptible values and actions tied to dominate sources of complex urban development pressures. In that context, this research aims to explore the significance of ‘value’ in master-planning at the residential neighbourhood and the pre-application planning phase of development, and further the understanding of strategic values-rich and value-based planning and design processes in both theory and practice. To achieve this purpose, a multidisciplinary constructive reasoning approach is adopted to iterate between theory and empirical observation to obtain new insights. This thesis is sub-divided into three main phases. The first phase explored meaning, concepts, and theories of master-planning, strategic choice decision-making, value, and values to propose a theoretical framework. The second phase adapted a survey method, following a review of key policies and literature, aiming to define the strategic role and the value of master-planning in Scotland. It was piloted with 7 experts and tested among 112 professionals who are involved in neighbourhood’s development in Scotland. To illustrate the effect of development pressures on stakeholders’ decisions, the second phase evaluates two carefully selected case studies in Scotland, focusing on different forms of master-planning, typical developer-led and private-public partnership development. Through detailed review of planning application documents and the conducted semi-structured interviews, the effect of the 2007-08 economic crises was analysed showing how decisions and actions are/were tied to a complex web of development forces at the macro, micro, and meso levels. Subsequently, a strategic values-rich and value-based view of master-planning is proposed through theoretical triangulation. This draws on theory to reach past the rational preconceptions that hobbled previous research efforts into defining the value of master-planning in planning and urban design. The main original contribution in this research is the development of an evolutionary ‘strategic value-based’ lens that re-defines the role of master-planning, revealing complex contradictions internal and external as a force of major hidden pressure on stakeholders taking decision. This work opens new horizons for spatial planning and urban design into the research field of value and values.
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Skerman, Fiona. "Modularity of networks." Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:1bbaaac7-bad0-469d-add4-6a0dbf75f7c6.
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Modularity is a quality function on partitions of a network which may be used to identify highly clustered components. It is commonly used to analyse large real networks, for example in social networks and protein discovery to find communities and related proteins respectively. Given a graph G, the modularity of a partition of the vertex set measures the extent to which edge density is higher within parts than between parts, and the maximum modularity q*(G) of G (where 0 ≤ q*(G) < 1) is the maximum modularity of a partition of V(G). In essence, modularity allows us to feed in large sets of data, and output a vertex partition with an associated score. Knowledge of the maximum modularity of random graphs is important to determine the statistical significance of the maximum modularity found on a real network. This thesis establishes numerical bounds on the likely maximum modularity for random regular graphs. The modularity of a random cubic network is shown to be whp in the interval (0.66, 0.81). This result has practical applications. It establishes that a large cubic network with modularity greater than 0.81 has a statistically significant clustering structure. The evolution of the maximum modularity of Erdös-Rényi random graphs as the edge probability increases is investigated. Three different phases of the likely maximum modularity are found. For np=1+o(1) the maximum modularity is 1 + o(1) whp and for np → ∞ the maximum modularity is o(1) whp. For np = c with c > 1 a constant, functions are constructed with 0 < a(c) < b(c) < 1 and b(c) → 0 as c → ∞ such that whp the maximum modularity is bounded between these functions. Concentration of the maximum modularity about its expectation and structural properties of any optimal partition are also established. Finding the maximum modularity of graph classes helps us understand the behaviour of the modularity function. We study trees, lattices and related graphs. The maximum modularity of a large k-ary tree was shown to be near 1 by Bagrow 2012. This was extended to trees with maximal degree o(n1/5) in Montgolfier et al. 2011. This thesis further extends the result to any tree with maximal degree o(n). Indeed it is shown that the maximum modularity will tend to 1 for any graph where the product of the treewidth and the maximal degree is much less than the number of edges. This shows random planar graphs typically have modularity 1 + o(1). Lower bounds were given in Guimerà et al. 2004 for the maximum modularity of complete sections of the integer lattice and for lattices with extra axis aligned edges included. The maximum modularity of any subgraph of this lattice is shown to be at least the same order of magnitude in the number of edges. This generalises to any graph which can be embedded in Euclidean space such that no edge is too long and no two vertices fall too close together.
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Frendem, Mathias Ormestad. "Great power politics in multipolar systems." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:76edbba9-28d5-48b0-ba00-618ab167f9db.
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My dissertation develops Georealism, a theory to explain how great powers behave in international relations. The dissertation has two main goals. One is that it aims to create a uniform theory of international relations, particularly balancing, bandwagoning, alliances, and war. The other is that it intends to explain the behaviour of individual great powers in detail, rather than just systemic outcomes. The basic premise of Georealism is that states face a threat both from their neighbours and from potential hegemons. In four chapters, I explore the implications of this insight on great power behaviour. First, I explain why continental states choose balancing or bandwagoning when faced with a potential hegemon. Second, I look at how offshore states behave towards the continental states to maximize their security. Third, I create a theory of the alliance choices of great power. Last, I explain which great powers go to war with each other and when. All the theoretical implications are well supported by quantitative and qualitative tests taken from various cases of European great power politics from 1683 to 1913. Georealism can indeed predict the behaviour and motivations of individual states with great accuracy on a variety of topics.
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Nash, William. "An experimental study into the behaviour of sulfur during Martian differentiation." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:77c31a3c-0799-4886-ba9e-8cf3ff48cc9c.
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A series of experiments related to igneous processes within Mars are presented, with a particular emphasis on the behaviour of sulfur during Martian magmatism. Of most significance are a series of one-atmosphere experiments conducted on a broad range of silicate melt compositions, under oxygen fugacity (fO2) conditions ranging from FMQ-1.67 to FMQ+1.6: a range which brackets much of the variation observed in Terrestrial and Martian igneous rocks. Quenched glasses from these experiments have been analysed by X-ray absorption Near Edge Spectroscopy (XANES) and Secondary Ion Mass Spectrometry (SIMS) to determine the speciation of their dissolved sulfur, as well as its overall concentration. The XANES spectra collected indicate the presence of the sulfide and sulfate species, and the progressive replacement of the former by the latter as fO2 increases. Clear differences are observed between the S6+/ΣS ratios of different silicate melts equilibrated under the same fO2 conditions, demonstrating that the major-element composition of a silicate melt has some measureable influence over sulfur speciation. The component most closely correlated with this change is FeO, whose presence in the silicate melt shifts the exchange between sulfide and sulfate towards higher fO2 conditions. This is interpreted as an outcome of coupling between sulfur and iron in the melts, and on this basis a quantitative relationship between log S6+/ΣS and log (Fe2O3/FeO2) is proposed. Such a relationship potentially provides an alternative to direct measurement of S6+/ΣS, but warrants further study to establish its generality. SIMS analyses of the most oxidized melts indicate a strong inverse correlation between their sulfate concentration and the abundance of the tetrahedrally coordinated cations Si and Ti, suggesting that sulfate solubility is governed by competition for tetrahedral sites in silicate melts. Additional experiments performed at 1.5GPa establish the sulfur concentration at sulfide saturation (SCSS) of a putative Martian primary melt at 1400°C. Experiments performed at the same pressure but under more oxidizing conditions constrain the sulfide-sulfate transition to between -1.5 and +0.8 log units relative to the Fayalite-Magnetite-Quartz (FMQ) buffer. This inference is supported by XANES spectra for these experiments, which show no evidence for mixed speciation. In addition to sulfur, the elements Sc, Y and a selection of REEs were also investigated at 1.5GPa. Partitioning coefficients were measured for these elements between a likely primary Martian melt, and three phases believed to be present in the Martian mantle: high- and low- calcium pyroxene and Fo76 olivine. The values obtained closely approximate those predicted by the lattice-strain model, suggesting that these elements partitioning behaviour is unaffected by the unusually Ferich chemistry of this melt. REE profiles generated by a simple partial melting model demonstrate the complexity of Martian meteorites' petrogenesis, including the need for chemically separate reservoirs within Mars' mantle. To assist in further investigations of Martian magmatism, in particular those involving sulfur, a method is presented for the manufacture of polycrystalline olivine capsules. These are suitable as containers for olivine-saturated melts in one-atmosphere experiments, and permit studies involving a wider range of melt compositions than those allowed by natural olivines (the presently used alternative). The equipment required for manufacture is readily available in most experimental petrology laboratories. Use of these capsules avoids common problems associated with using wire loops, such as their propensity to absorb iron, or to react with the sulfur in the experimental charge.
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Burton, Tara Isabella. ""Narrative dandyism" : the theology of creation in the French decadent-dandyist novel, 1845-1907." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:4bb3da1e-a2f8-40bf-ba9c-c960ebf6976c.
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This thesis explores how selected "decadent-dandyist" writers of late 19th century France at once exemplify and subvert the self's act of shaping and imprinting its own selfhood upon the world: a model in which an autonomous, discrete artist-self freely creates, and in which both reader/audience and artistic "subjects" are treated as raw canvas and denied agency of their own. Storytellers like Barbey D'Aurevilly, Villiers de l'Isle-Adam, J.K. Huysmans, and Remy de Gourmont create not only hyper-artificial, cloistered, "auto-telic" (to use Charles Taylor's term) textual worlds (e.g. Huysmans' theïbade raffinée) but also hyper-artificial selves: presenting themselves and their often autobiographical protagonists as dandy-artists for whom artistic creation is an extension of self-creation. Central to this thesis is the 19th century figure of the dandy - he who, to quote D'Aurevilly, "[causes] surprise in others, and [has] the proud satisfaction of never showing any oneself." Appropriating the divine power of self-fashioning, the dandy transforms the chaos of existence into a clear narrative over which he alone exerts control, denying that he himself is subject to the control of the world. In my thesis, I first explore the cultural and economic roots of this understanding of the autonomous dandyist-artist in the light of wider tensions in 19th century Paris. I then explore selected "decadent-dandyist" texts through close reading, focusing on the theological implications of our authors' treatment of narrative, character, setting, and language: showing how our writers cast doubt on both the possibility and morality "autonomous" creation on theological grounds. Finally, I ask how constructive theologians might learn from our authors' condemnation of "dandyist" storytelling to create a new Christian aesthetics for the novel: proposing elements of an alternate, "kenotic" novel, in which self-projection gives way to "self-giving", a model based not on power and ego but rather on love.
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Johnson, Jennifer. "Georges Roualt's modernism and the question of materiality." Thesis, University of Oxford, 2014. https://ora.ox.ac.uk/objects/uuid:5e1ac77a-ba70-41e8-a3cd-5189723f487f.
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The central concern of my thesis is to bring into focus the problematic relation between Georges Rouault's (1871-1958) pictorial vocabulary and his subject matter: on the one hand, abstract mark-making and on the other, a refusal to cede to abstraction or formalism through an insistence that these marks remain yoked to representation. The result is an examination a way of painting that embraces its state of uncertainty, which interrogates its own construction, and strains against the very materiality it simultaneously celebrates. Chapter one traces the critical reaction to Rouault's painting in the early years of the twentieth century, which was at best mystification, and at worst, disgust. This chapter also analyses the thick painterly terms of these paintings and their resistance to conventional meaning, arguing that there are parallels between Rouault's project and contemporary experimental forms of art and literature within modernism. Chapter two continues this exploration, attending to the various relationships between surface and depth that are interrogated by Rouault's canvases. These relationships reveal the deep philosophical and theological questions at stake Rouault's painting. Chapter three explores a theological reading of Rouault's work beginning with the aesthetics of his associate, the French Catholic philosopher, Jacques Maritain - a reading that shows how painting can be true to its material conditions and strain towards a higher, albeit obscure, form of knowledge. Against this, the last chapter argues that the paintings also support the possibility of a bleaker world-view, aligned with Dostoyevsky's kenotic theology, in which matter potentially overwhelms the possibility of transcendental meaning. In conclusion, I argue that Rouault's painting interrogates the vocabulary of modernism and presents the 'fallen' or 'wounded' state of a painting that acknowledges its material conditions.
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Jackson, Andrew. "Understanding the experience of the amateur maker." Thesis, University of Brighton, 2011. https://research.brighton.ac.uk/en/studentTheses/199e24e3-a04a-4aec-ba99-094dc0708411.
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This study asks: what are the internal rewards associated with amateur making, and how do they offer satisfaction and fulfilment to those who participate in the activity? People considered in this research make furniture, jewellery, model engineering projects, canoes and cars. They all maintain and make use of an amateur workshop of some kind, and use a variety of tools, machines and materials in their constructions, carrying out work-like activity as a form of leisure. The research aims to understand amateur making not purely as a form of symbolic production – as the fabrication of signs and symbols that have a life after the making process is complete – but to focus instead on the experience of making, and the material interaction that occurs as part of practice.
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Bish, Nigel B. "Dielectric condition monitoring using intelligent partial discharge analysis." Thesis, University of Brighton, 2003. https://research.brighton.ac.uk/en/studentTheses/5dfeb20c-6066-41b8-ba10-59ae9a7877af.
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Rumball, Hannah Frances. "The relinquishment of Plain dress : British Quaker women's abandonment of Plain Quaker attire, 1860-1914." Thesis, University of Brighton, 2016. https://research.brighton.ac.uk/en/studentTheses/a570d202-ba98-47ae-bc3e-c9a401f7fc5b.
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This thesis discusses how British Quaker women negotiated relinquishing their religiously prescribed Plain dress from 1860 to 1914 in the context of developments in Quaker feminine identity. This thesis approaches its subjects by examining the primary source of surviving Quaker garments in British dress collections. These items provide the basis from which research methodologies and the personal narratives of Quaker women and their case studies are developed. Surviving garments, alongside historical letters, diaries, religious texts, department store catalogues, photographs and period dress illustrations are analysed in order to understand how women Quakers practised their religion and organised their public appearance through dress during this period. The original quality of this research is the outcome of an interdisciplinary approach. No other research project in the international dress history or religious history fields has discussed and critically considered the identity of British Quaker women through an analysis of their surviving clothing between 1860 and 1914. This aspect of British social history and therefore British identity has until now remained unexplored and unacknowledged. By 1860 Quakerism had undergone extreme doctrinal upheaval, which had led to the abandonment of those rules which enforced Plainness of speech and apparel that same year. Even prior to 1860, this thesis reveals that some women were incorporating fashion into their religious Plain dress, by using fashionable silhouettes and high-quality fabrics albeit eschewing bright colours and ornamentation. After 1860 however, male and female Quakers had complete individual freedom of choice in their clothing. During this period of religious turmoil, female Victorian Quakers vocalised a range of opinions on women's emancipation, education and welfare, on their role within the religious society and their opinions concerning dress through published correspondence in Quaker journals. This thesis identifies a variety of views concerning dress between 1860 and 1914, as Quaker women negotiated their individual freedom of choice in attire in a ternary manner. Moreover, this thesis proves that this ternary interpretation was acknowledged by Quakers themselves and discussed within Quaker journals in the 1860-1914 period. Quakers of the period identified these ternary interpretations as ascetic, moderate and fashionable. This thesis proposes a new set of classifying terms, Non-Adaptive, Semi-Adaptive and Fully-Adaptive, in reflection of the extent to which Quaker women adapted their religious clothing to incorporate fashion alongside their differing interpretations of Quaker belief. Four case studies illustrate further these three adaptive interpretations, and show how individual Quaker women chose to present themselves to their religious community and wider society.
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Pate, Judy. "The changing contours of the employment relationship : a case study of the psychological contract." Thesis, Abertay University, 2001. https://rke.abertay.ac.uk/en/studentTheses/54420944-ba80-4d7d-8a82-4801bd062712.
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In recent years organisations have been faced with increasing challenges which have resulted in tensions between innovation and cost effective strategies. Such environmental pressures have resulted in the emergence of a new employment relationship or psychological contract. In the face of this new situation two questions become apparent: ‘how can the new psychological contract be managed effectively?’ and ‘what are the organisational consequences of an ineffectively managed psychological contract?’ This thesis evaluates two key research questions: ‘what factors shape psychological contracts?’ , and ‘what are the implications of breaking such a contract?’ In order to address these questions academic literature was reviewed in Chapter 2, and it is argued that the concepts of context, trust and fairness are key variables that shape psychological contracts. Two new models of psychological contract breach and violation are presented using both processual and variance methodologies. This thesis adopts a postpositivist methodological standpoint, as highlighted in Chapter 3, and draws on both quantitative and qualitative approaches from a longitudinal case study of an industrial textile organisation described in Chapter 4. The findings of research question 1 were presented in Chapter 5, and these suggest that psychological contracts are complex and dynamic, and therefore context is crucial to understanding the nature of the relationship. Furthermore it was found that the notion of fairness impinges on the psychological contract and perceptions of injustice had negative affects on employee attitudes. It was evident that trust was crucial in understanding the psychological contract, however, it was found that personal trust or shared norms between employee and employer were not essential for a positive psychological contract - issues expanded upon in Chapter 6. Research question 2 was addressed through the evaluation of two new models of psychological contract breach and violation, using both quantitative and qualitative methodologies. These results were discussed in Chapter 8, and the qualitative data on balance concurred with the processual model. It was evident through the evaluation of the variance model that triggers of psychological contract breach affected attitudes rather than engendering behavioural changes.
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Symonds, Charles P. "The improvement of product sustainability by the development of 'whole life' design methodologies." Thesis, Oxford Brookes University, 2015. https://radar.brookes.ac.uk/radar/items/6802d96b-5a05-4fcf-ba97-4cebd126c8ba/1/.
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Sustainability-related legislation has increased over the past 10 years, and this is now having a profound effect on industry which is required to reduce its impacts. Those designing and manufacturing electro-mechanical products must also consider the impacts of the goods they produce. Many of these impacts stem from decisions made early on in the design process, and consequently it is here that effort must be focused. One of the most significant lifecycle stages of any product is end of life, as it dictates how much of the material and embedded energy are recovered for reuse. Remanufacturing was found to be the only end of life option for electro-mechanical products that returned a product to a like-new quality, without first destroying the form of the component and loosing the embodied energy. Although remanufacture can require a high level of reprocessing, the process can be simplified if products are designed to facilitate this. Current design models in this area, however, offer inadequate assistance to designers, leading to confusion and a lack of real life application. Through the use of a case study, this study set out to explore whether the impacts of electro-mechanical products could be reduced, by considering products on a component level and designing them to operate over multiple lives, without increasing cost or reducing quality. This proved to be true in the case of a stairlift. Through life cycle assessment it was demonstrated that the whole life environmental impacts of a stairlift, representing a sample electro-mechanical product, could be significantly reduced by remanufacturing components at end of life. High impact components were targeted for remanufacture using the LCA data in combination with cost, sending the remainder of the product for recycling. Overall, environmental savings of 13% were witnessed. Incorporating sustainability in this fashion not only avoided any increase in cost to the manufacturer, but achieved a 34% reduction in overall production costs. It was concluded that if the product had been optimised with desirable characteristics for remanufacture and recycling when in design, then these savings would be even more significant. To guide designers with embedding desirable characteristics into products, the end of life optimisation (EOLO) model was developed. This provides a framework for selecting components early in the design process for either remanufacture or recycling. The model goes on to rate current performance and provided guidelines on how to improve the design going forward.
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Dupas, Rémy. "Apport des méthodes d'apprentissage symbolique automatique pour l'aide à la maintenance industrielle." Valenciennes, 1990. https://ged.uphf.fr/nuxeo/site/esupversions/7ab53b01-cdfb-4932-ba60-cb5332e3925a.
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Cette thèse est consacrée à l'étude des méthodes d'apprentissages symbolique automatique en vue de leurs applications dans le domaine de la maintenance industrielle. Plus précisément, l'apport des méthodes d'apprentissage inductives basées sur la recherche de similarités entre exemples est envisagé à deux niveaux distincts. Le premier niveau concerne le domaine de la maintenance corrective. L'approche présentée aborde le développement et la mise en œuvre d'un module d'acquisition automatique de connaissance de surface pour le système expert de diagnostic technique Sediag. Ce module basé sur l'utilisation du système inductif Charade, engendre un système de règles à partir des informations mémorisées au cours des sessions de diagnostic antérieures. Le second niveau d'aide, relatif à la maintenance préventive aborde la conception d'un système à base de connaissance dédié à l'exploitation de la base de données des historiques de maintenance. Cette approche repose sur l'association de deux types de connaissances. Le premier est la connaissance induite par le module d'apprentissage à partir de la base de données. La connaissance générale d'experts en maintenance préventive constitue le second type de connaissance utilisé. Le système ainsi réalisé permet d'automatiser l'exploitation des historiques de maintenance et de fournir des conseils de prévention dont l'objectif est d'accroitre l'efficacité de cette maintenance. Enfin, est proposée une architecture intégrée de système à base de connaissance utilisant des méthodes d'apprentissage symbolique automatique pour l'aide à la maintenance corrective et préventive.
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Hill, M. "The effects of acute and chronic upper and lower body exercise on postural sway and functional balance." Thesis, Coventry University, 2015. http://curve.coventry.ac.uk/open/items/4b2cd55c-0027-4f54-ba9e-4d231a4e982d/1.
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Acute lower body exercise elicits adverse effects on balance performance and subsequent fall risk. However, little information exists for upper body exercise and postural sway. The series of experimental studies presented in this thesis investigated the effects of acute upper and lower body exercise on postural sway in healthy young and older adults and determined whether the acute negative effects of exercise can be removed by an improvement in training status. Chapter 4 examined the effects of maximal and submaximal (absolute and relative exercise intensities) arm crank ergometry (ACE) and cycle ergometry (CE) on postural sway in young healthy adults. Cycling elicited an immediate increase in post exercise postural sway whereas ACE did not. Chapter 5 compared the effects ACE, CE and treadmill walking (TM) on postural sway in healthy older adults. Based on the findings of Study 1, submaximal exercise was performed at the same relative intensity (50 % HRE). In agreement with Chapter 4, CE and TM elicited post exercise balance impairments lasting for ~ 10 min post exercise. ACE performed at the same relative intensity as the lower body did not elicit post exercise balance impairments in older adults. Collectively, these acute studies suggest that lower limb exercise may acutely increase fall and injury risk in the immediate period after exercise cessation. This is important because practitioners and clinicians should acknowledge that the prescription of conventional training modes might potentially elicit transient impairments in neuromuscular function. However, in this context it appears that seated exercise with the arms may not induce a significant enough stimulus to cause sensorimotor disturbance to postural stability and thus may be a safer alternative exercise mode for fall risk populations or individuals who are very sedentary. Chapter 6 examined differences in balance performance, as measured by quantitative posturography and functional balance tests, among different age groups. Measures of postural sway were able to distinguish between younger (< 60 years) and older ( > 60 years) adults whereas functional performance tests suggested that balance impairments were observed earlier ( > 50 years). This study enabled a range of tests to be determined for use with subsequent training interventions. Chapter 7 examined the effects of 6-weeks upper or lower body exercise training on postural sway. Upper and lower body training elicited similar improvements in specific (~ 25 %) and cross transfer (~ 12 %) exercise tolerance. Both modes of training elicited favourable balance adaptations. Specifically, upper body training improved mediolateral aspects of postural sway, while lower body training improved anteroposterior aspects of sway. It was proposed that an improvement in cross transfer exercise capacity after upper body exercise reduced the physiological strain experienced during CE, thus reducing post exercise balance impairments and that an increase in abdominal and trunk strength from upper body exercise training reduced sway following ACE. Importantly, ACE also elicited an improvement in functional reach distance and timed up and go test speed. Conversely, CE improved lower limb strength which elicited an improvement in lower body dynamic balance. It is likely that engaging in both upper and lower body exercise will be better that either mode of exercise alone for both health and fitness and balanced incorporated in everyday life. ACE elicits a number of significant benefits to cardiovascular fitness and balance which is important for a number of older subgroups who might have difficulty engaging in lower limb exercise, such as those who are very sedentary, those with lower limb injury/disease or undergoing surgery rehabilitation and individuals who are overweight. Specifically, ACE may offer a pathway from sedentary living to physical activity. Upper body endurance exercise can contribute to a multimodal training stimulus by eliciting favourable adaptations in fitness, functional performance and balance. Such responses are important because this type of exercise may serve a feasible and time-efficient training regime for older adults, which will likely result in improved attrition and adherence to physical activity.
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Gernoux, Gwladys. "Transfert de gène à l'aide d'AAV dans le muscle squelettique : effet de la voie d'administration du vecteur sur le système immunitaire de l'hôte." Nantes, 2013. http://archive.bu.univ-nantes.fr/pollux/show.action?id=8e348334-ba95-4b08-8ec9-7a987b9d546e.
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Les vecteurs dérivés des virus adéno-associés (AAVr) sont des outils de choix pour la thérapie génique. En absence d'une réponse immune, ils permettent une expression à long terme du transgène s'ils sont administrés en intramusculaire (IM). Néanmoins, cette voie ne permet pas de cibler un nombre suffisant de muscles pour le traitement de myopathies et est souvent associée à une réponse immune envers le produit du transgène. Cette immunotoxicité pourrait-être due à une concentration du vecteur in situ, résultant en une interaction rapide et importante du vecteur avec le système immunitaire de l'hôte, comme nous l'avons confirmé chez la souris. La voie locorégionale (LR), qui consiste à injecter le vecteur par voie intraveineuse sous pression dans un membre isolé, apparait aujourd'hui comme une alternative attractive. Elle permet de transduire efficacement les muscles du membre injecté, sans induire de rejet du produit du transgène. Pour confirmer ces observations ainsi qu'évaluer l'impact du type de promoteur sur l'immunotoxicité de la voie LR, des primates ont été injectés avec un vecteur codant pour une protéine immunogène sous le contrôle d'un promoteur ubiquitaire ou alors spécifique du muscle. Nos résultats montrent que, quel que soit le promoteur, la voie LR permet une expression à long terme du transgène immunogène dans le muscle malgré la survenue d'une réponse immune spécifique. Contrairement à la voie IM, la voie LR ne semble pas entrainer de signaux inflammatoires in situ suffisants pour induire une réponse immune délétère envers le transgène. Cette voie apparait donc comme prometteuse pour le traitement de myopathies par thérapie génique à l'aide d'AAVrAdeno-associated viral (AAV) vectors are promising tools for gene therapy. In the absence of any immune response, a single intramuscular (IM) injection can result in long-term transgene expression. However, this mode of delivery is not able to target large skeletal muscle territories and is often associated to the immune rejection of the transgene product in large animal models. This immunotoxicity could be explained by an in situ vector concentration resulting in early and strong interactions between the vector and the host immune system, as we confirmed in a mouse model. As an alternative, locoregional (LR) mode of delivery could be an attractive alternative. It consists in an isolated limb perfusion under pressure. LR was shown to allow the transduction of large skeletal muscle areas in the injected limb and without inducing transgene rejection. To confirm these observations, and in order to evaluate the impact of the promoter type on vector-associated immunotoxicity, non-human primates were injected with an AAV vector encoding an immunogenic protein under the control of either the ubiquitous CMV or the desmin muscle-specific promoters. Our results show that, whatever the promoter used, LR route leads to persisting transgene expression in the muscle despite a specific immune response. In contrast to IM delivery, LR route seems to result in insufficient in situ inflammatory signals to induce immune transgene rejection. In conclusion, LR mode of administration nowadays appears promising for AAV-based gene therapy of myopathies
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Idrissi, Najlae. "La navigation dans les bases d'images : prise en compte des attributs de texture." Phd thesis, Nantes, 2008. https://archive.bu.univ-nantes.fr/pollux/show/show?id=84546d6f-7efd-4662-ba95-e74b15907689.
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Ce travail de recherche entre dans le cadre des systèmes de recherche d’images par le contenu, en particulier la recherche par la texture. Le but de ce travail est de permettre à l’utilisateur de naviguer dans de grande base de données d’images sans formulation de requêtes en un langage d’interrogation spécifique. Pour atteindre cet objectif, nous avons réparti le travail en deux grands volets. Le premier volet concerne l’extraction et l’identification d’un modèle de texture composé d’attributs pertinents. Pour atteindre cet objectif, nous avons proposé d’étudier deux modèles de texture : les matrices de co-occurrences et les attributs de Tamura. La sélection et la validation du modèle caractéristique ont été faites à partir de plusieurs applications que nous avons proposées dans le cadre de cette thèse après réduction de la dimension de l’espace de représentation des modèles de texture. Ensuite, la navigation s’effectue à l’aide de treillis de Galois avec une interface HTML tout en passant par une phase d’interprétation du modèle de texture numérique en un modèle sémantique. Le problème de transcription du numérique au sémantique est considéré comme un problème de discrétisation des valeurs numériques continues. Un autre problème se manifeste lorsque la taille de la base des images augmente, les performances du système de navigation se dégradent. Pour pallier à ce problème, nous proposons de créer des résumés qui de plus permettent de focaliser la recherche et la navigation sur un ensemble d’images cibles et non pas sur toute la baseThis work contributes to the field of Content-based Image Retrieval (CBIR) particularly texture-based retrieval. The main goal of this work is to enable the user to navigate through a large image database without making any query in specific language. To achieve this goal, we divided the work into two main parts. The first part involves the extraction of a texture model made of relevant attributes. We proposed to study two models of texture: the co-occurrence matrices and Tamura’s attributes. The selection and validation of the model features are based on several applications that we have proposed in this thesis after reducing the dimension of the representation’s space. Then, navigation is achieved using Galois’ lattices with a simple HTML interface while passing through a phase of interpretation of numerical model texture into a semantic model. The problem of the transcription from the numerical values to the semantics is regarded as a problem of discretisation of continuous attributes. Another problem occurs when the size of the database of images increases: the performance of the navigation system are deteriorating. To overcome this problem, we propose to use techniques of summarisation to create summaries that help users to navigate through target collections instead of the whole database
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Patzelt, Annika Verfasser], Dietmar [Akademischer Betreuer] Zinner, Julia [Akademischer Betreuer] Fischer, and Peter M. [Akademischer Betreuer] [Kappeler. "The Social System of Guinea Baboons (Papio papio) With a Focus on Male-Male Relationships / Annika Patzelt. Gutachter: Julia Fischer ; Peter Kappeler. Betreuer: Dietmar Zinner." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2013. http://nbn-resolving.de/urn:nbn:de:gbv:7-11858/00-1735-0000-0001-BAE0-4-1.
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Shahin, Mazhar Verfasser], Wolfgang [Akademischer Betreuer] Holtz, Matthias [Akademischer Betreuer] Gauly, and Eva [Akademischer Betreuer] [Schlecht. "Pregnancy-associated glycoprotein (PAG) profiles in cows and goats and attempts to measure PAG in milk / Mazhar Shahin. Gutachter: Matthias Gauly ; Eva Schlecht. Betreuer: Wolfgang Holtz." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2013. http://nbn-resolving.de/urn:nbn:de:gbv:7-11858/00-1735-0000-0001-BAB0-0-4.
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Darles, Emmanuelle. "Représentation et rendu de l’océan en synthèse d’images réalistes." Limoges, 2008. https://aurore.unilim.fr/theses/nxfile/default/2ad0d72b-74d1-4984-ba70-1e253c8bd256/blobholder:0/2008LIMO4037.pdf.
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De nos jours, les images de synthèse sont omniprésentes dans notre quotidien. Le réalisme de ces images est grandissant, surprenant, et il n’est souvent pas aisé de distinguer la réalité de la virtualité, cette réalité faite et enrichie par toute la complexité des phénomènes naturels qui nous entourent. L’eau est un de ces phénomènes dont la variété et la richesse dynamique rend la représentation complexe. Nous nous intéressons dans cette thèse à sa forme la plus étendue, celle des océans, qui font partie intégrante de nos paysages. Dans un premier temps, nous étudions les méthodes permettant la simulation et le rendu de l’océan à la fois dans le domaine physique mais aussi dans le domaine de la synthèse d’images réalistes. Dans le second chapitre, nous proposons une nouvelle méthode de rendu unifiée permettant une visualisation plus rapide de l’océan au large et permettant d’approximer les échanges lumineux surfaciques et sous-surfaciques, l’écume et les phénomènes d’éblouissements. Dans le chapitre 3, nous nous intéressons au déferlement des vagues en proposant une nouvelle approche adaptative basée physique permettant de reproduire ce phénomène et de réduire les temps de calculs imposés par la résolution des équations de la mécanique des fluides en 3D. Dans le quatrième chapitre, nous étendons ce modèle en proposant une approche hiérarchique permettant une plus forte accélération du processus de résolution et d’obtenir une simulation proche de l’interactivitéNowadays, computer generated images are very present in our everyday life. Realism of these images is increasing, surprising and it isn’t often easy to distinguish the reality of the virtuality, this reality made by all the complexity of the natural phenomena which surround us. Water is one of these phenomena among which the variety and the dynamic comportment produce complex representation. We are interested in this thesis in its most area shape, that of the oceans, which are a part integral of our landscapes. At first, we study the methods allowing the simulation and rendering of the ocean in the physical domain and in computer graphics. In the second chapter, we propose a new rendering method unified allowing a faster visualization of ocean surface and allowing to approximate scattering and sub-scattering exchanges of light, foam and glare effects. In the chapter 3, we are interested to breaking waves by proposing a new physical based adaptive approach allowing to reproduce this phenomenon and to reduce time of calculations imposed by the resolution of equations of the fluid mechanics in 3D. In the fourth chapter, we extend this model by proposing a hierarchical approach allowing a stronger acceleration of the process of resolution and to obtain a simulation close to interactivity
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Noguès-Delbos, Elise. "Densification de dépôts de zircone yttriée projetés par plasma d'arc Ar-H2 et N2-H2 pour leur utilisation dans l'industrie des semi-conducteurs." Limoges, 2007. https://aurore.unilim.fr/theses/nxfile/default/f9f2a754-9ac0-4af7-ba80-4c3d38c21d1b/blobholder:0/2007LIMO4047.pdf.
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Dans l’industrie des semi-conducteurs, les puces électroniques, au cours de leur processus de fabrication, peuvent être revêtues d’un dépôt CVD et/ou PVD, réalisé dans des enceintes en quartz (bell jar). Après utilisation, ces dernières, recouvertes d’un dépôt « polluant », sont nettoyées dans une solution acide. Dans le but d’augmenter la durée de vie de ces enceintes et d’espacer les nettoyages, la société Edwards les protège d’un dépôt rugueux de zircone yttriée réalisé par projection plasma. Cependant, la porosité du dépôt protecteur entraîne une infiltration de la solution chimique de nettoyage jusqu’au quartz. Non seulement, le dépôt « polluant » est décapé, mais aussi le dépôt protecteur en zircone yttriée. L’objectif de cette thèse est de densifier le dépôt de zircone yttriée afin de le rendre imperméable à la solution chimique, permettant sa réutilisation en ne décapant que le dépôt « polluant ». La rugosité du dépôt doit, toutefois, rester élevée. La densification des dépôts va se faire à partir d’une optimisation des paramètres de projection - débit massique, pourcentage d’hydrogène, distance de tir,… - de la distribution granulométrique de la poudre, de la nature du gaz plasmagène (argon ou azote) et donc de la torche utilisée. Cette optimisation des conditions de tir est effectuée via l’étude des propriétés du plasma, telles que l’enthalpie et les fluctuations de tension aux bornes de la torche, et de leurs influences sur le traitement thermique des particules en vol, la formation des lamelles lors de leur écrasement et la construction des dépôts et leurs propriétés (en particulier leur porosité, rugosité et épaisseur)In semiconductor industry, the electronic chips, during their manufacturing process, can be covered with CVD/PVD coatings, carried out inside bell jars. After use, these quartz chambers, layered with a contaminated coating, are cleaned inside an acid solution. In order to increase their time of life and the time between two cleanings, Edwards society masks the chambers with a rough yttria partially stabilized zirconia coating made by plasma spraying process. However, the chemical cleaning solution reaches the quartz substrate through the coating porosity. So, the protected coating is etched at the same time than the contaminated coating. The aim of this research work is to increase the coating density to make it cleanable, in order to remove only the contaminated layer. Nevertheless, the coating roughness must remain high. The coating densification is obtained by optimising the plasma spray parameters (mass flow rate, hydrogen percentage, stand-off distance…), the powder size distribution, the plasma gas mixture composition (argon or nitrogen) and so the plasma torch design. This optimisation of spray conditions is determined by studying plasma properties, such as its enthalpy and its voltage fluctuations, and their influences on the in-flight particle thermal treatment, the corresponding splat formation and the coating growth and properties (especially their porosity, roughness and thickness)
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Pocock, Adam Craig. "Feature selection via joint likelihood." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/feature-selection-via-joint-likelihood(3baba883-1fac-4658-bab0-164b54c3784a).html.
Full textAbstract:
We study the nature of filter methods for feature selection. In particular, we examine information theoretic approaches to this problem, looking at the literature over the past 20 years. We consider this literature from a different perspective, by viewing feature selection as a process which minimises a loss function. We choose to use the model likelihood as the loss function, and thus we seek to maximise the likelihood. The first contribution of this thesis is to show that the problem of information theoretic filter feature selection can be rephrased as maximising the likelihood of a discriminative model. From this novel result we can unify the literature revealing that many of these selection criteria are approximate maximisers of the joint likelihood. Many of these heuristic criteria were hand-designed to optimise various definitions of feature "relevancy" and "redundancy", but with our probabilistic interpretation we naturally include these concepts, plus the "conditional redundancy", which is a measure of positive interactions between features. This perspective allows us to derive the different criteria from the joint likelihood by making different independence assumptions on the underlying probability distributions. We provide an empirical study which reinforces our theoretical conclusions, whilst revealing implementation considerations due to the varying magnitudes of the relevancy and redundancy terms. We then investigate the benefits our probabilistic perspective provides for the application of these feature selection criteria in new areas. The joint likelihood automatically includes a prior distribution over the selected feature sets and so we investigate how including prior knowledge affects the feature selection process. We can now incorporate domain knowledge into feature selection, allowing the imposition of sparsity on the selected feature set without using heuristic stopping criteria. We investigate the use of priors mainly in the context of Markov Blanket discovery algorithms, in the process showing that a family of algorithms based upon IAMB are iterative maximisers of our joint likelihood with respect to a particular sparsity prior. We thus extend the IAMB family to include a prior for domain knowledge in addition to the sparsity prior. Next we investigate what the choice of likelihood function implies about the resulting filter criterion. We do this by applying our derivation to a cost-weighted likelihood, showing that this likelihood implies a particular cost-sensitive filter criterion. This criterion is based on a weighted branch of information theory and we prove several novel results justifying its use as a feature selection criterion, namely the positivity of the measure, and the chain rule of mutual information. We show that the feature set produced by this cost-sensitive filter criterion can be used to convert a cost-insensitive classifier into a cost-sensitive one by adjusting the features the classifier sees. This can be seen as an analogous process to that of adjusting the data via over or undersampling to create a cost-sensitive classifier, but with the crucial difference that it does not artificially alter the data distribution. Finally we conclude with a summary of the benefits this loss function view of feature selection has provided. This perspective can be used to analyse other feature selection techniques other than those based upon information theory, and new groups of selection criteria can be derived by considering novel loss functions.
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Da, Silva Sarah Janine. "The institutions of literary colonialism : George Eliot, Anthony Trollope, and the Cape Colony." Thesis, King's College London (University of London), 2017. https://kclpure.kcl.ac.uk/portal/en/theses/the-institutions-of-literary-colonialism(63c7b3cb-ba9e-468e-9f45-eea5c1bbd9f0).html.
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This thesis is an investigation into the formation of white belonging in South Africa, focalised through what I call the institutions of literary colonialism – the public library, the postal service, and the colonial press. I also use George Eliot and Anthony Trollope, both of whom had personal connections to South Africa, as case studies. Their interactions with the three institutions of literary colonialism allow me to situate their works within the colonial institutional setting of which they formed a part, and also facilitate an investigation into how the exercise of white power over the indigenous African population was aided by literary and cultural institutions. However, rather than tracing a history of white settlement in the Cape, this thesis argues that white belonging was founded on a sense of unsettlement and ambivalence, which was articulated through the institutions of literary colonialism. At the heart of this project is a tension between the Cape colonists’ desire to imitate and emulate British literary practices, whilst at the same time begin to articulate a sense of ‘colonial nationalism’ though the development of white settler literary culture, institutions and forms of knowledge. I argue that this tension was the driving force behind the development of the Cape’s literary culture. Whilst the remoteness and insularity of the Cape meant that its cultural institutions were dependant on imported metropolitan cultural norms and products, its distance from the metropole also enabled the development of a distinct and unique literary culture. I explore this entanglement of desires for colonial autonomy and for sustained connections to Britain by interrogating how literary culture was ‘made’ in the Cape Colony.
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Mohamad, Azhar. "Empirical essays on short selling." Thesis, Bangor University, 2012. https://research.bangor.ac.uk/portal/en/theses/empirical-essays-on-short-selling(4a88aa2e-ec69-44da-bac0-bac47326fa55).html.
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This thesis sets out to analyse empirically the impact of: i) short selling on stock returns; ii) the UK Financial Services Authority's (FSA) short selling ban on stock prices, market quality as well as contagion, and iii) short selling on Exchange Traded Fund's (ETF) returns. A distinction is made between two types of shorts: valuation and dividend arbitrage shorts. Employing an event-study methodology, the empirical results indicate that, whilst large increases in short interest in valuation shorts are associated with significant negative abnormal returns, large increases in dividend arbitrage shorts are less informative. This may imply that these two different types of shorts are executed by two different sets of traders, who are scrutinizing two different sets of information. With respect to dividend arbitrage shorts, however, the informational content of short interest is dependent on the state of the economy. Regarding the impact of the FSA's short-selling ban on stock prices and market quality, the current study finds no evidence that the FSA's objective of protecting market quality was achieved through its prohibition of the short selling of financial stocks. Nevertheless, with regard to the FSA's concerns over cross-sectoral contagion, there is evidence that the short-selling ban may have been successful in preventing contagion, thereby protecting capital market stability. In relation to the informational content of ETF short interest, the present study finds that high increases in short interest are followed by positive abnormal returns, while low increases in short interest are followed by negative abnormal returns. The results indicate that ETF's short interest does not carry informational content similar to that contained in the short interest on individual stocks and different types of players are involved in the ETF market, namely, the hedgers and speculators.
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Gifford, Mary. "Lord Berners : aspects of a biography." Thesis, King's College London (University of London), 2007. https://kclpure.kcl.ac.uk/portal/en/theses/lord-berners--aspects-of-a-biography(3b644374-52bd-48f8-ba92-23b5707bc02f).html.
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