VictorJuiz/thesis huggingface dataset:
Mathematical modelling of electronic contact mechanisms in silicon photovoltaic cells

In screen-printed silicon-crystalline solar cells, the contact resistance of a thin interfacial glass layer between the silicon and the silver electrode plays a limiting role for electron transport. The motivation of this project is to gain increased understanding of the transport mechanisms of the electrons across this layer, which can be exploited to provide higher performance crystalline silicon solar cells. Our methodology throughout is to formulate and analyse mathematical models for the electron transport, based on the drift diffusion equations.
In the first chapter we outline the problem and provide a summary of relevant theory. In Chapter 2 we formulate a one-dimensional model for electron transport across the glass layer, that we solve both numerically and by employing asymptotic techniques. Chapter 3 extends the model presented in Chapter 2 to two dimensions. To solve the two-dimensional model numerically we devise and validate a new spectral method. The short circuiting of current through thinner regions of the glass layer enables us to find limiting asymptotic expressions for the average current density for two different canonical glass layer profiles. In Chapter 4 we include quantum mechanical effects into the one-dimensional model outlined in Chapter 2 and find that they have a negligible effect on the contact resistance of the glass layer. We model the boundary effects present at the silicon emitter-glass interface in Chapter 5. Finally, in Chapter 6 we summarise our key results, suggest possible future work, and outline the implications of our work to crystalline silicon solar cell manufacturers.

Keywords: Asymptotic analysis
Electrochemical systems
Drift-diffusion
Advisor: Howell, P
Breward, C
At home in the world: Czesław Miłosz and the ontology of space

Space constitutes one of the main leitmotifs of Czes&lstrok;aw Mi&lstrok;osz's work, both theoretical and poetic. Central in this respect is the notion of imagination as a faculty organizing space, the faculty which, from the times of the Scientific Revolution, has been subject to erosion, especially as far as the religious imagination is concerned. The abolition of the anthropocentric, hierarchical vision of space, threw human beings into a state of alienation, conceptual nowhere. Religion was replaced by the dogmatism of scientific reductionism, the reality of Ulro. Mi&lstrok;osz shows the way out of Ulro, the way out of nowhere to the somewhere.
This thesis aims to illustrate the conceptual map of the way out of Ulro as portrayed in four selected volumes of poetry and the novel Dolina Issy, anchored in different points of Mi&lstrok;osz's biography. The Land of Ulro, the collection of essays which encapsulate Mi&lstrok;osz's ideas on space, constitutes a canopy work for the interpretation of the practical realization of those ideas in Mi&lstrok;osz's poetic work. Trzy zimy (1936), &Sacute;wiat, poema naiwne (1943), Miasto bez imienia (1969), and Druga przestrze&nacute; (2002) provide the material for the analysis of different aspects of Mi&lstrok;osz's conception of space. Subject to analysis is the relationship between object and human subject as regards the formative, childhood experience of the space of the house (manor) and surrounding landscape, the act of building space on the basis of memory and retrospection in the context of distance and exile, and the workings of religious imagination in the context of the realm of second space.
Through his conception of space, Mi&lstrok;osz defends human existence in its completeness. He shows the way out of Ulro. This thesis aims to retrace Mi&lstrok;osz's map out of the land of alienation on the basis of the poet's selected works.

Keywords: Polish poetry
city
religion
house
object
memory
exile
space
ontology
catastrophism
Advisor: Fellerer, J
Hybrid quantum information processing with continuous and discrete variables of light fields

Quantum correlations play a fundamental role in quantum information science. The variety of their manifestations has become increasingly apparent following the development of novel light sources, protocols and photodetectors. One broad classification identifies two instances of non-classical correlations: particle and mode entanglement. These categories mirror two coexisting descriptions of quantum systems in terms of discrete and continuous variables of the electromagnetic field. The past decades have generated a number of promising results based on schemes which encompass elements from both frameworks, rather than viewing the two descriptions as mutually exclusive. In this context, it is possible to conceive and realise experiments where either the quantum resource or the detection system is 'hybrid'. Optical weak-field homodyne detectors bring together phase sensitivity and photon counting; as such, they represent a detection scheme which works across continuous and discrete variables of the radiation field.
In this thesis we present a two-mode weak-field homodyne detection layout with added photon-number resolution and apply it to the study of a split single-photon state and a squeezed vacuum state. As a first test of the capabilities of this system, we investigate the reconstruction of relevant features of a given quantum resource - such as its photon statistics - with our detection scheme. Further, we experimentally demonstrate the observation of an instance of non-classical optical coherence which combines the continuous- and discrete-variable descriptions explicitly.
The ability to probe phenomena at the interface of wave and particle regimes opens the way to novel, improved schemes for quantum information processing. From a more fundamental perspective, such hybrid approaches may shed light on the very roots of quantum enhancement.

Keywords: hybrid quantum technologies
photon-number-resolving detectors
quantum coherence
weak-field homodyne detection
Advisor: Walmsley, I
Effect of hypoxia on cardiac metabolism and function in the type 2 diabetic heart

Type 2 diabetic patients have impaired cardiac ischaemia-reperfusion recovery and higher rates of mortality following a myocardial infarction. Hypoxia is a key component of ischaemia and therefore, this thesis is aimed to investigate the effect of hypoxia on metabolism and contractile function of the type 2 diabetic heart. In combination with high fat feeding, different doses of streptozotocin (STZ) (15, 20, 25 and 30 mg/kg) were used to determine the optimal dose needed for induction of diabetes in male Wistar rats. A novel type 2 diabetic model was developed and characterised by hyperinsulinaemia, hyperglycaemia and dyslipidaemia. The effects of chronic hypoxia were investigated by housing diabetic rats in a hypoxic chamber (11% O2) for 3 weeks. Results showed that the HIF signalling pathway was not impaired in diabetic hearts. PPARα targets (MCAD, UCP3 and PDK4) were downregulated by chronic hypoxia in control hearts but not in diabetic hearts, suggesting PPARα overactivation in diabetic hearts. Acute hypoxic perfusions (16 minutes normoxia, 36 minutes hypoxia and 20 minutes reoxygenation) were performed to investigate the effect of acute hypoxia on metabolism and cardiac function. Diabetic hearts had impaired metabolic response to acute hypoxia, associated with decreased cardiac function during acute hypoxia and reoxygenation. In the final study, sulfo-N-succinimidyl oleate (SSO), a FAT/CD36 inhibitor was administered prior to acute hypoxia to modulate metabolism in diabetic hearts. The previously seen maladaptation of diabetic hearts to acute hypoxia was improved by SSO. In diabetic hearts, SSO increased glycolysis during acute hypoxia, and normalised fatty acid oxidation and decreased triglyceride deposition upon reoxygenation, associated with improved cardiac function at the end of experiment compared to untreated diabetic hearts. In conclusion, the elevated lipid metabolism contributed to metabolic inflexibility in diabetic hearts, which is associated with the impaired response to hypoxia, and the inhibition of lipid metabolism was associated with improved cardiac function in diabetic hearts following hypoxia.

Advisor: Evans, R
Heather, L
Functional and clinical relevance of oscillatory activity within cortico-basal-ganglia circuits in Parkinson’s disease

Over the past 20 years there have been significant advances in our understanding of how synchronised neural oscillations relate to cognitive and motor processes both in health and in neurological disease. Oscillations can be considered from the point of view of being the observations of the latent dynamical properties of interacting populations of neurones. With this in mind it becomes evident that their study may inform about underlying functional architectures and principles governing motor and cognitive control.
Cortico-basal-ganglia circuits are canonical feedback loops between cortical and sub-cortical structures, with well-defined anatomy which makes them ideal for the study of oscillatory phenomena. Moreover, these circuits are known to play crucial roles in motor and cognitive processes such that impairments of their normative function may lead to neurological disease states. In this thesis I focus on insights about oscillatory function from cortical-basal ganglia recordings in Parkinson's disease.
I will present evidence from studies showing that the roles of beta (15-30 Hz) and gamma (60–90 Hz) oscillatory activities in motor control are intricately linked to task specific cognitive-motor demands. Furthermore, the timing of activities within these frequency bands relative to movement reveals how distinct spectral phenomena may relate to distinct aspects of cognitive and motor processing. An intricately related aim of this thesis is to begin to establish how the preferred frequencies of interaction and the topographies of long range oscillatory networks within cortico-basal-ganglia loops relate to specific clinical symptoms. In this regard, I will present data revealing the modulation of cortico-basal ganglia coupling by movement, and Parkinson's disease therapies such as levodopa and Deep Brain Simulation (DBS). Novel methodological developments that facilitate such insights are presented. Finally I discuss how these insights contribute to existing understanding of the pathophysiology of Parkinson's disease, in addition to suggesting novel future therapeutic strategies for DBS.

Advisor: Brown, P
Litvak, V
The major transitions in evolution

The history of life has involved several major evolutionary transitions that have each led to the emergence of a new individual. Examples of major transitions in individuality include the evolution of the eukaryotic cell, multicellular organisms and eusocial societies. In each of these events, previously independently replicating units (cells, individuals etc.) cooperate to form a new individual, which can then only replicate as a whole. For this to occur, conflict between individuals needs to be minimised, to allow maximising their inclusive fitness to be roughly equivalent to maximising group fitness. It has been predicted that the way in which social groups form should be key for eliminating conflict between individuals and promoting cooperation. In this thesis, I have focused on two major evolutionary transitions; the evolution of multicellularity and the evolution of symbiosis, and show that the mode of group formation (whether groups are parentoffspring associations or not) is crucial for understanding when and why major transitions occur. Firstly, I show that the major transition to obligate multicellularity has only occurred with clonal group formation (where cells remain together after division). Secondly, I use an experimental system to show that predation pressure may be key in promoting the formation of multicellular groups in algae. Finally, I show that the mode of group formation is also important in between-species transitions. I use the evolution of symbiosis to show that transmission route of symbionts and environmental factors, determine how cooperative symbionts will be towards their hosts.

Advisor: West, S
The anthropology of Hilary of Poitiers

This thesis examines the theological of the fourth-century bishop, Hilary of Poitiers, concentrating particularly on two commentaries written at different times in his life.
The thesis starts by examining the texts, and demonstrates that Hilary's commentary on Psalm 118 is loosely speaking a translation of Origen; by comparing both authors with Ambrose, the relationship between Origen and Hilary appears much closer than previously thought.
The main body of the thesis examines Hilary's anthropological theology. Three chapters look at created human nature, looking at the relationship between body and soul, human nature as imago dei, and the extent to which human nature can be treated as a platonic universal. The general conclusion is that Hilary is not particularly platonic, and at this stage is not particularly stoic either, but rather is eclectic in his choice of philosophical ideas. The influence of Origen is clear but Hilary only uses Origen’s theology critically.
There follow four chapters on the Fall and its impact, focussing particularly on its effects on human nature. In particular it is shown that Hilary presages Augustine's teaching of the fallen will; in Hilary the Will is described as being in thrall to her mother-in-law Disobedience. Another human malady is the effect of the passions or emotions, where Hilary is influenced by Stoic ideas of the process of human action; nevertheless, concepts such as apatheia or the propatheiai do not appear in his work. These constraints on human action point towards Hilary's theology of original sin; indeed he appears to be the first author to use the phrase peccata originis in this sense.
In the concluding chapter, Hilary's place in the continuum between Origen and Augustine is demonstrated; at very least, original sin cannot be called an African doctrine, since it first is named by Hilary, a Gaul.

Keywords: Patristics
Origen
Original Sin
Emotions
The will
Augustine
Hilary of Poitiers
Advisor: Edwards, MJ
Shipped out? Pauper apprentices of port towns during the industrial revolution, 1750-1870

The thesis challenges popular generalisations about the trades, occupations and locations to which pauper apprentices were consigned, shining the spotlight away from the familiar narrative of factory children, onto the fate of their destitute peers in port towns. A comparative investigation of Liverpool, Bristol and Southampton, it adopts a deliberately broad definition of the term pauper apprenticeship in its multi-sourced approach, using 1710 Poor Law and charity apprenticeship records and previously unexamined New Poor Law and charity correspondence to provide new insight into the chronology, mechanisms and experience of pauper apprenticeship.
Not all port children were shipped out. Significantly more children than has hitherto been acknowledged were placed in traditional occupations, the dominant form of apprenticeship for port children. The survival and entrenchment of this type of work is striking, as are the locations in which children were placed; nearly half of those bound to traditional trades remained within the vicinity of the port. The thesis also sheds new light on a largely overlooked aspect of pauper apprenticeship, the binding of boys into the Merchant service. Furthermore, the availability of sea apprenticeships as well as traditional placements caused some children to be shipped in to the ports for apprenticeships. Of those who were still shipped out to the factories, the evidence shows that far from dying out, as previously thought, the practice of batch apprenticeship persisted under the New Poor Law.
The most significant finding of the thesis is the survival and endurance of pauper apprenticeship as an institution involving both Poor Law and charity children. Poor children were still being apprenticed late into the third quarter of the nineteenth century. Pauper apprenticeship is shown to have been a robust, resilient and resurgent institution. The evidence from port towns offers significant revision to the existing historiography of pauper apprenticeship.

Advisor: Humphries, J
Transcranial stimulation of the human primary motor cortices

The primary aim of this thesis is to investigate the physiological effects of transcranial direct current stimulation (tDCS) as applied to the primary motor cortex (M1). This research was largely motivated by the need to understand the basic physiological changes of tDCS, in order to evaluate its use as a potential tool in recovery after stroke, as well as its more general applicability as a tool to modulate plasticity. The experiments in this thesis assess the ability of tDCS to modulate the primary motor cortex in healthy controls.
The effects of tDCS on cortical GABA and motor resting state functional connectivity were measured with magnetic resonance spectroscopy (MRS) and resting functional MRI (fMRI). Anodal stimulation reduced GABA concentration and increased functional connectivity in the stimulated M1. Testing these changes within the same individuals demonstrated that the magnitude of changes do not correlate across subjects. Novel evidence on the timecourse of GABA change demonstrated that the reduction in GABA is most prominent in the 30-minute period after stimulation.
To determine whether the tDCS-induced modulations in inhibition is restricted to the stimulated hemisphere or whether inhibitory changes could be observed in the nonstimulated M1, or in the interhemispheric connections between the M1s, transcranial magnetic stimulation (TMS) was used to measure intracortical inhibition in each M1 and interhemispheric inhibition and facilitation in the contralateral M1. There were no polarity-specifc effects on intracortical inhibition within either M1, and no changes in interhemispheric excitability from the stimulated to non-stimulated M1.
Development of a two-voxel MRS method at ultra high field (7 Tesla) allowed for concurrent measurements of cortical neurotransmitters from both M1s with excellent spectral quality and GABA quantifcation. This method was used to demonstrate the timecourse of tDCS-induced changes in neurochemicals concurrently from both M1s. Anodal stimulation reduced GABA in both the anode-targeted and non-stimulated M1. Cathodal stimulation decreased GABA and glutamate in the non-stimulated M1, with no concurrent changes in the cathode-targeted M1. Bilateral stimulation reduced glutamate in both M1 with no change in GABA.

Keywords: Transcranial stimulation
Transcranial direct current stimulation
tDCS
Motor plasticity
Plasticity
GABA
Stroke
Motor cortex
Advisor: Stagg, CJ
Johansen-Berg, H
Associative political culture in the Holy Roman Empire: the Upper Rhine, c. 1350-1500

Historians have long struggled to conceptualise the Holy Roman Empire in the later middle ages. This thesis seeks to provide an interpretation of political life in the Empire which captures the structures and dynamics in evidence in the sources. It does so through a comparative study of the varied socio-political elites along the Upper Rhine between 1350 and 1500, with frequent reference to other regions of the Empire. The thesis is divided into three sections. Part I, consisting of four chapters, examines the shared and interconnective characteristics of several spheres of activity – the documentary, judicial, ritual, military, and administrative – in which various elites interacted through the same practices and conventions. Part II (five chapters) deals with the types of contractual association which emerged organically from these shared and interconnective structures and practices. It shows that these associations – leagues, alliances, judicial agreements, coinage unions, and others – were more common and more similar than typically assumed, that they regulated key judicial and military affairs, and that they reflected a shared ideology which emphasised peace-keeping and the common good within the Empire’s framework. Part III of the thesis shows how the structures and dynamics explored in Parts I and II played out in specific situations by reference to three case studies in the 1370s-'80s, 1410s-'30s, and 1460s-'70s. All three demonstrate how the 'associative political culture' model can illuminate events which were previously considered to be moments of crisis or chaos, or the products of 'territorial' or 'constitutional' processes. The thesis concludes by arguing that, in light of this evidence, the Holy Roman Empire is best understood as a community of interdependent elites who interacted within a shared 'associative political culture'. This conclusion highlights the need for a new paradigm beyond those of the 'territory', the 'constitution', or the centralising 'state'.

Keywords: German history
Political history
Early modern
Political culture
Fifteenth century
Late medieval
Late middle ages
Central Europe
Holy Roman Empire
Advisor: Watts, J
Modeling deforestation and examining trade-offs among carbon stocks and benefits to livelihoods and biodiversity for REDD+ planning in Kenya

Reducing deforestation and degradation (REDD&plus;) can lower anthropogenic carbon emissions by 9-11% and is therefore integral to mitigating climate change. REDD&plus; is a proposed scheme in which developed countries pay developing countries for reduced deforestation. Kenya is one such country participating in REDD&plus;. As such, Kenya must establish a reference emission level (REL) against which it can compare avoided emissions from reduced deforestation. Developing a spatial model of future deforestation will determine the REL for Kenya and provide complementary information on where forests are at risk and drivers of deforestation. REDD&plus; also offers benefits of poverty alleviation and biodiversity conservation, referred to as "co-benefits." Since the spatial distributions of carbon and co-benefits may not be congruent, there may be trade-offs among them whereby increasing one decreases others. To assist Kenya in its REDD&plus; preparations, I build the first spatially explicit deforestation model for the whole of Kenya parametrized with national data. I apply a novel Bayesian inference method which propagates uncertainty in the estimated parameters to the predictions. In addition, I conduct a novel analysis of trade-offs among carbon and co-benefits in three dimensions. I find that predicted forest loss is 1.68% ± 0.06% from 2013 to 2018 (cross-validated AUC = 0.8). There is high deforestation in the Rift Valley and coastal regions attributed to drivers related to accessibility, extraction, and agriculture. Analysis of three-dimensional trade-offs reveals that REDD&plus; sites could simultaneously include 86% of the maximum possible number of people in poverty and 88% of the maximum possible average proportion of ranges of rare species with the smallest 25% of global ranges with a 10% reduction in carbon. The results presented here may help Kenya spatially target REDD&plus; interventions and address particular deforestation drivers as well as plan for securing high levels of carbon stocks and co-benefits.

Keywords: spatially-explicit model
poverty
REDD+
deforestation
uncertainty
trade-offs
biodiversity
co-benefits
Kenya
Advisor: Grenyer, R