VictorJuiz/thesis huggingface dataset:
Bayesian Gaussian processes for identifying the deteriorating patient
Keywords: Precision Medicine
Bayesian Statistics
Artificial Intelligence
Medical Statistics
Personalised Medicine
Gaussian Processes
Bayesian Timeseries
Timeseries
Machine learning
Healthcare

Patients discharged from the ICU will commonly be placed in intermediary care, such as the step-down ward, where the nurse-to-patient ratio is reduced (compared to that of the ICU). Although most of these patients will continue to recover and stabilise, a significant portion will suffer cardiac arrest and/or other clinical emergencies, and readmission into intensive care. Upon readmission, the risk of mortality is significantly higher than that of the general ICU population. Evidence suggests that early detection of deterioration may prevent or alleviate the severity of clinical emergencies. Notable shortcomings of current practices are that they (i) involve manual calculation of risk scores, (ii) depend on heuristic decision criteria, (iii) ignore time-series dynamics of physiological measurements, and (iv) lack patient-specificity.
Gaussian process regression (GPR) models are proposed as a principled, probabilistic method to address the clinical need to continuously monitor patient vital-sign time-series with the flexibility to address the aforementioned weaknesses of current methods. The proposed GPR models focus on the robust forecasting of patient vital-sign time-series and early detection of patient deterioration. The primary contributions of this thesis describe how:
1. Probabilistic models may be used to identify artefactual measurements from continuously-acquired vital-sign monitoring devices.
2. GP covariance functions may be constructed and regularised for robust modelling, suitable for both patient-cohorts and personalised care.
3. GPR-based methods may quantify erratic physiological time-series and provide useful advanced warning of deterioration events.
Each of the above contributions use the time-series correlation of vital-sign measurements for advantageous clinical inference.
Essays in experimental economics
Keywords: behavioral economics
survey experiments
social preferences

In the first chapter, I investigate the impact of income inequality on anti-social behaviour through an experiment. Participants are first assigned to two different kinds of groups: equality groups, where everyone is paid the same amount for performing a simple task, and inequality groups, where people receive different amounts for completing the same task. Each participant is then told that one member of their group will have the possibility of taking some of the money earned by another group member. Contrary to the predictions made by the Becker model and the Fehr-Schmidt inequity aversion model, participants in the inequality groups steal significantly less from a fellow group member with the same income as them than people in the equality groups. The second chapter, jointly written with Christopher Roth, examines the influence of economic status on pro-social behaviour using a large experiment with a representative sample of the US population. We exogenously alter people's perceived economic status by changing where they think their household stands in the US income distribution. Half of the people who over-estimated their position in the income distribution are told that they are relatively poorer than they thought. Conversely, half of those who under-estimated their position in the income distribution are informed that they are relatively richer than they thought. Then, participants play a series of four incentivised games, which measure different social preferences, such as trust, negative reciprocity, honesty and altruism. We show that individuals who learn that they are lower (resp. higher) in the income distribution than they thought become less (resp. more) satisfied with their relative position in the income distribution, but that their behaviour remains unchanged in the four behavioural games. The third chapter, co-written with Christopher Roth and Diego Ubfal, studies whether providing information about immigrants affects people's attitude towards them. First, we use a large representative cross-country experiment to show that, when people are told the share of immigrants in their country, they become less likely to state that there are too many of them. Then, we conduct two online experiments in the US, where we provide half of the participants with five statistics about immigration, before evaluating their attitude towards immigrants with self-reported and behavioural measures. This more comprehensive intervention improves people's attitude towards existing immigrants, although it does not, on average, change people's policy preferences regarding immigration. However, Republicans become more willing to increase legal immigration after receiving the information treatment.
Why do ABCC5 KO mice show a lean phenotype?
Keywords: endocrinology
ABCC5
brown
GLP-1
metabolism
beige
adipose

ABCC5 is an ATP-dependent membrane transporter that has been shown to transport glutamate conjugates in mammalian systems. Global loss of ABCC5 from mice causes a lean phenotype with enhanced enteroendocrine GLP-1 secretion. Here we develop a protocol for the live imaging of GLP-1 secretion in vitro using a model L-cell line. ABCC5 KO gut histology analysis shows no difference in gut villi length or surface area between WT and KO mice. Despite numerous studies showing enhanced brown adipose tissue (BAT) and white adipose tissue (WAT) thermogenic capacity in the presence of elevated GLP-1 levels, data presented here do not show increased non-shivering thermogenesis occurring in our KO animals. Analysis of fat pads from ABCC5 KO mice show that both their BAT and epididymal WAT depots have significantly lower mass than WT depots. Western blot and H&E; histological analysis suggests that inguinal WAT depots of ABCC5 KO mice may show a lack of browning. We theorise that the adipose physiology described is due to changes in glutamatergic signalling in the sympathetic nervous system innervating BAT and WAT. Finally, we conclude that the lean phenotype of ABCC5 KO mice cannot be attributed to an increased thermogenic capacity of BAT and WAT.
Towards a Catholic epistemology
Keywords: Implicit Faith
Faith and Reason
Augustine
Newman
Reformed Epistemology
Aquinas
Anonymous Christianity
Plantinga

In this thesis, I develop a Catholic analysis of faith and reason, drawing on insights from a movement in contemporary analytic philosophy: Reformed Epistemology. In my first chapter, I explain that despite criticism from Catholic philosophers, Reformed Epistemology provides a broadly salutary model of faith. Inspired by Reformed Epistemology, I develop a further model (“Counter-Reformed Epistemology”) which is philosophically defensible, and which accords well with a set of theological desiderata for such a model drawn from the Church’s dogmatic teaching about faith. These desiderata include divine faith consisting of propositional assent to divine revelation which is (at least, in paradigm instances) perfectly certain, rationally tenacious and freely chosen. I argue that CRE accounts for these properties of faith better than competing analyses of faith advanced by Catholic philosophers. In the second chapter, I expand my sketch of CRE, to show how it can account for the possibility of “implicit” Catholic faith in those who non-culpably fail to believe in the gospel. In doing so, I also compare CRE to the insights of Rahner and von Balthasar, who are important representatives of modern approaches to “fundamental theology”. In the remainder of my thesis, I aim to show that CRE has considerable precedent in Catholic theological tradition. In successive chapters, I argue that Augustine, Aquinas and Newman all advanced religious epistemologies which to different degrees bear considerable similarities to CRE, engaging with various modern interpretations of their work. The support of authors in the tradition should lend plausibility to my model from a Catholic perspective, meaning that Catholics with “basic” belief in divine revelation can be fairly confident that their belief is epistemically fitting. In all, I argue that Reformed Epistemology provides the resources to develop a model of faith that accords well with a traditional Catholic understanding of faith and reason.
The dynamics of hepatic lipid metabolism in humans: understanding their role in fatty liver disease
Keywords: Metabolism
DGAT2
NAFLD
Steatosis
Fatty acid
Nutrition

Non-alcoholic fatty liver disease (NAFLD) has become increasingly prevalent. It is associated with changes in hepatic and whole-body fatty acid (FA) metabolism, with the first stage of the disease, steatosis, characterised by excess triacylglycerol (TAG) storage with a specific (macrovesicular) lipid droplet (LD) pattern; the final step in TAG synthesis is catalysed by diacylglycerol acyltransferase (DGAT). Although the pathogenesis of NAFLD is known to include both genetic and lifestyle factors, the sequence of events that precedes lipid accumulation in the liver remains unclear.
Human hepatoma cell lines (HepG2 and Huh7 cells) were optimised for use as models of hepatic FA metabolism. Use of human serum in the cell media resulted in reduced de novo lipogenesis (DNL) and improved levels of FA oxidation and secretion in both cell lines; Huh7 cells were used for subsequent experiments. To create a macrovesicular LD pattern, low (glucose only) and high (glucose and fructose) levels of sugar were added to the media in combination with low and high concentrations of FAs. The addition of high fat high sugar (HFHS) media to Huh7 cells caused accumulation of large LDs in a more macrovesicular pattern, which was similar to steatotic primary hepatocytes.
Low and high sugar and fat treatments were used on CRISPR-modified Huh7 cells with DGAT2 knocked out; changes in these cells included a reduction in TAG secretion, DNL and glucose uptake from the media. In the HFHS treatment, DGAT2 knockout was associated with signs of oxidative stress and inflammation, suggesting an interaction between substrate availability and DGAT2 function. Recruitment of controls and people carrying a DGAT2 mutation who took part in a sugar overfeeding intervention demonstrated that a change in DGAT2 function may impact systemic glucose disposal, evident by increased carbohydrate oxidation and a resistance to metabolic changes caused by sugar overfeeding.
Overall, I developed physiologically-relevant models of hepatocellular metabolism and steatosis. Investigations using these models in parallel with human participants identified altered DGAT2 function as having a potential role in NAFLD.
An international perspective on teacher’s self-efficacy: Investigating personal, cultural, structural and environmental factors
Keywords: quantitative methods
TALIS
teachers' self-efficacy
international comparative research

This study investigates the variation of predictors of teachers’ self-efficacy (TSE) in 32 OECD countries and a sub-set of three country clusters containing Anglo-Saxon, Nordic and East and South-East Asian countries (ESEA), offering a cultural perspective on TSE. TSE is defined as a tripartite measure comprising TSE in student engagement, instruction and classroom management. It has been found to be a useful tool to explain differences as to why some teachers are convinced of their ability to bring about change in their students’ learning, while others do not believe in their abilities. The study makes use of the Teaching and Learning International Survey (TALIS) 2013, published by the OECD, that has information of about 104.000 teachers in about 6.500 schools. It is one of very few multi-level studies in the field and brings together variables describing the teachers, the classroom, the principal and the school.
Firstly, it was found that the three domains of TSE are related to the predictors in different ways and most variation in terms of the relationship was found for the classroom setting. Proportionally, most variation could be explained within schools, whereas individual differences between teachers accounted for most variation in TSE within teachers. Secondly, the predictors were associated differently in each domain of TSE across the three country clusters, as i.e. most classroom predictors were significant in the ESEA countries, but rather few in the Nordic countries, whereas student background features were relevant for ex-plaining variation in the Anglo-Saxon countries.
This study was able to contribute to providing levers for education policy and practice to improve the workplace of teachers. It shed light on to how teachers in different cultural settings experience TSE in different ways, although they work in similar institutions. The large sample size allowed robust and generalizable results as well as the application of advanced statistical methods like multilevel- and structure equation modelling. Hence, the study contributes to knowledge on a methodological, practical and theoretical level.
Driven colloidal particles in optical potential energy landscapes
Keywords: Colloids
Optical tweezing

The dynamic behaviour of colloidal particles driven across one-dimensional optical potential energy landscapes is studied. Colloids are driven with a piezo-stage, manipulated with optical tweezers and magnetic ﬁelds and imaged using optical microscopy. First, the meta-stable horizontal and vertical states of a colloidal rod in a single optical trap close to a ﬂat wall are explored. A colloidal rod is then driven through a periodic optical potential energy landscape. The equilibrium position of a rod driven below the critical velocity is found to vary substantially from that of a sphere due to the friction coeﬃcient of a rod being highly dependent on its proximity to an optical trap. At higher velocities, a colloidal rod is shown to act similarly to a colloidal sphere, exhibiting dynamic mode locking. Colloidal spheres are then driven across a time-dependent one-dimensional optical potential energy landscape with diﬀerent modes of dynamic mode locking being observed. The mode locked step width is shown to vary with the oscillation frequency and the coupling strength between the particle and the optical landscape. The particle transport across the time-dependent landscape is also studied by measuring the eﬀective diﬀusion coeﬃcient which is highly sensitive to the driving velocity and mode locking. Next, chains of interacting colloidal particles are driven through a time-independent optical potential energy landscape. A mismatch between the length scales of the chain and the landscape gives rise to a freely sliding chain in an Aubry-type transition. In this regime a chain exhibits zero static friction despite being subject to a potential energy landscape. Chain motion is inspected for a driven ﬂexible chain that is seen to exhibit breathing modes. Introducing oscillations in the driving force leads to dynamic depinning, which is aﬀected by both the frequency and amplitude of the oscillations. Finally, the stochastic thermodynamics for particles driven across an optical landscape is considered. The work done by a particle in both a time-independent and a time dependent optical landscape is measured. The optical work in a time-independent landscape is shown to be zero. However, the time-dependent counterpart exhibits a ﬁnite amount of work due to the optical landscape. The magnitude of the observed total work is considered in light of the mechanism of particle motion along with analysis of the contributing optical work and driving work.
The role of accounting in realigning corporate purpose: Essays on carbon accounting and reporting practices
Keywords: Sustainability reporting
Carbon accounting

The general theme explored in this thesis is the role of accounting in realigning corporate purpose. To this end, this study presents three papers, each from a different perspective, examining the role of carbon accounting and reporting practices in redefining the role of corporations in addressing climate change.
The first paper (Chapter 3: Corporate perspective) examines the role of the external carbon reporting requirements in influencing managerial decision-making. Based on a field study informed by semi-structured interviews with 30 sustainability managers in large UK-based companies, this paper demonstrates that the introduction of the carbon reporting requirements enabled the sustainability managers to initiate and implement some degrees of changes to the business practices. However, the paper also shows that they simultaneously inhibited the managers from addressing the unquantifiable and unprofitable aspects of climate change. As such, the paper highlights the positive role of carbon accounting and reporting practices, but also the risk that they may serve to create a ‘false’ sense of comfort.
The second paper (Chapter 4: Voluntary regulatory body’s perspective) examines the role of the ‘harmonisation work’ of voluntary regulatory bodies in making climate change reporting ‘comparable’ with financial reporting. Based on a case study of the Climate Disclosure Standards Board (CDSB) informed by semi-structured interviews with its 13 key personnel and 2-month participant observation, this paper demonstrates that the harmonisation work enabled the CDSB to initiate some degrees of changes to the corporate reporting practice. However, the paper also shows that there is a risk that it may inadvertently lead the CDSB into an ‘institutional trap’ through which changing the corporate reporting practice becomes seen as the ultimate objective, instead of changing the underlying business practice.
The third paper (Chapter 5: Regulatory perspective) examines the role of the UK Financial Reporting Council (FRC) in shaping the formulation of a policy proposal which sought to mandate climate change reporting practice. Based on archival analysis of the public consultation documents, this paper demonstrates that the FRC played a subtle ‘thought leadership’ role in shaping the way that the actors involved in the regulatory debate perceived the issue. This, in turn, created a ‘regulatory-policy loop’ which supported the policy makers’ formulation of the proposal. As such, the paper highlights the role of the corporate reporting regulator in supporting the formulation of the carbon accounting and reporting regulation by creating a sense of shared interest between the business and the NGOs communities.
Examining functional plasticity in the human brain
Keywords: Motor learning
Reward
Memory

The ability to quickly learn and adapt behaviour is critical to animal survival. Recent evidence has shown that short-term training can induce widespread changes in the neural activity across the brain. In this thesis, I conducted a series of studies that examined the behavioural and neural consequences of short-term training in humans.
In Chapter 3, I showed that resting-state functional connectivity could detect task- specific changes. However, I also observed changes that were not task-specific, and even occurred when participants had no training. This experiment demonstrates that resting-state functional connectivity is an appropriate tool for studying plasticity and also highlights the importance of experimental controls in plasticity research.
In Chapter 4 and 5, I investigated the impact of reward and punishment on performance during skill learning. In Chapter 4, I focused on how task-demands interact with skill the learning, and in Chapter 5, I focused on whether the learner’s intention to learn modifies the impact of reward and punishment.
In Chapter 6, I used resting-state fMRI to elucidate the impact of reward and punishment on the neural activity evoked by training on two different tasks. I determined that reward and punishment evoked different neural patterns after training, but that the precise regions affected by feedback processing depended on the task being trained.
In Chapter 7, I conducted a preliminary investigation into the neurochemical basis of resting-state functional connectivity using a novel MRSI technique. I found a preliminary link between the distribution of the inhibitory neurotransmitter GABA and network-level functional connectivity. I also found that the interaction between GABA concentration and network-level functional connectivity may be associated with sensorimotor performance.
Collectively, these studies demonstrate the short-term training induces wide- spread changes throughout the brain. These changes are influenced by the task being trained as well as contextual influences. In addition, these findings raise new questions into the physiological basis of network level plasticity that can be addressed in the future.
Rethinking rural development, food and agriculture in Colombia: examination of competing narratives during the agrarian strikes and negotiations 2013-2016
Keywords: agrarian movements
social movements
agrarian strikes
agriculture
indigenous
African-Colombian
agrarian change
rural development
food sovereignty
Colombia
food
peasants

There has been a resurgence of interest in the Agrarian question in the developing world, especially in Latin America. Colombia’s development trajectory cannot be fully understood without paying serious attention to the unresolved agrarian question. This thesis explores the negotiations that took place between the government and the agrarian movements in the aftermath of the 2013-2014 national strikes. For the first time in decades in Colombia, the national government agreed to negotiate with the representatives of the peasant, indigenous and African-Colombian peoples, the country’s poorest and most marginalised communities. In this context, the thesis addresses the following questions: (1) what are the alternative narratives of food provision that emerged in the agrarian strikes and negotiations in Colombia in the period 2013-2016? (2) To what extent have new coalitions of agrarian movements emerged around alternative narratives of food provision? (3) How are alternative narratives interfacing with dominant ones, and what are the potential outcomes for agrarian policy? In studying the emergence of two national agrarian movements, the thesis argues that the debates on food provisioning - who produces what and who consumes what, where and with what effects - have become central, and that the different actors involved in them - agrarian movements, the state, and the food industry - have different and often competing visions. Conceptually the thesis goes on to argue that the agrarian question, beyond its conventional formulation, could be reframed as a question of food. In addition to being a contribution to scholarship on the Agrarian question in Colombia, the thesis addresses key issues for sustainable rural development, agri-food systems and the future of the peace-agreement implementation.