VictorJuiz/thesis huggingface dataset:
Investigating the extent to which informal mentoring by recently retired teachers of Physics can support beginner teachers of Physics to grow in their teacher knowledge and influence their retention in teaching

The experiences of beginner teachers of physics in their first year of teaching and the factors affecting their intentions to remain in the profession are explored and contrasted with what is known from the literature. Findings from this include feelings of isolation, lack of subject specific support and low time availability of supportive colleagues in schools. These, and what is known about teacher professional learning, are used to inform a small-scale qualitative study of using recently retired physics teachers to informally mentor new teachers of physics over a period of one year. Case studies of the mentor and mentees are presented using data from the contents of mentoring conversations and these are analysed to explore the extent to which this type of informal mentoring can support professional knowledge growth in new physics teachers and influence their decisions to remain in the profession. Findings show that the main areas of professional knowledge addressed by the mentoring are behaviour management and pedagogical content knowledge (PCK). A key factor in the success of the mentoring was its informality and relationship to other forms of support and mentoring available to the new physics teacher. Implications for teacher educators about the benefits and limitations of this type of mentoring are considered and proposals for further study made.

Keywords: MTED 2020
MTED
Towards large scale quantum networks

Quantum computing has the potential to solve problems that take current classical computers much longer to solve. The last two decades witnessed a substantial development of various physical platforms, most of which have shown a "Proof of principle" demonstration for quantum computing. We are now in a critical stage where the goal is to develop the system to a large scale so that we can make quantum computing useful for real world applications. However, the question of which physical platform shows most promise remains uncertain. In this thesis, I examine two mainstream platforms: linear optics and trapped ions, from the point of view of scalability. For each platform, my own work has focused particularly on how to model and engineer the temporal properties of single photons.
For linear optical quantum computing, I propose to use an off-resonant cascaded absorption (ORCA) buffer to purify and unify the single-photons from different noisy sources. A proof of principle experiment is demonstrated to show that the ORCA buffer is in principle, noise-free. Simulation suggests that with the current ORCA buffer, we can purify the single-photon source better than with ideal intensity filtering. Meanwhile, it can unify different sources and increase the inter-indistinguishability from 60% to 96%.
For the trapped ion system, one promising scalable approach is to use photons to mediate entanglement between ions in remote traps. To achieve this, ion-photon entanglement must first be generated. We propose to use a cavity-enhanced Raman transition on the D3/2 → P3/2 → D5/2 λ-system' in a strontium ion level scheme for ion-photon entanglement generation. A full mathematical description is constructed to describe the entanglement dynamics considering the Rayleigh-scattering-induced temporal mixing noise. With this theory, simulation shows that we expect to achieve ion-ion remote entanglement rate of more than 75KHz with negligible infidelity from temporal mixing noise. Both proposals, if fully demonstrated experimentally, will be powerful tools to solve the scalability challenge for their respective systems, paving the way towards large scale realistic quantum computing.

Keywords: remote entanglement
temporal mixing
quantum computer
trapped ion
cavity enhancement
atomic ensemble
single photon source
Advisor: Goodwin, J
Education, aspiration, and mobility in the Karen borderlands: An ethnography of youth transitions amongst the Kwaegabon Plong Karen of southeastern Burma/Myanmar

Existing research on education-to-employment transitions in complex and contested settings in the global South is consumed with the debilitating effects of the ‘crisis of youth’ and its negative outcomes in which many emerge un/under-employed. Young people are often depicted as in thrall to this predicament rather than probing their agentive capacities for affirmative action to move beyond the impasse. Consequently, few studies explore how youth transitions relate and respond to wider socio-economic and political transformation as young people set about changing the self and the situation.
Based on fieldwork conducted throughout 2015 and 2016 in a remote region of southeastern Burma/Myanmar emerging from decades of armed conflict, government restriction and underdevelopment, this thesis explores how a community of Plong Karen in the Karen State capital Hpa-an, engaging around alternative forms of higher education, are responding directly to local configurations of privation and possibility. By shaping the aspirations and agency of high school and university students to safeguard the legacy of this, this provision amounts to a formidable vision and vehicle of social change.
Adopting an interdisciplinary approach, I bring a concern for temporalities into conversation with socio-spatial mobilities to explore ways in which young people navigate their structured positions and exploit the possibilities around them before and into Myanmar’s political transition, and across the Karen borderlands into neighbouring Thailand. I explore how specific struggles and successes around education, shared by this particular social ‘generation’ across these time-spaces, have informed their capacity to act and the manner in which they are doing so. I suggest that these outcomes are stimulating broader socio-economic transformations within and beyond this community. Access to this education and the opportunities it promises, nevertheless presents young people with new and beguiling possibilities beyond the constraints and concerns of those communities, which remain marked by the spectre of intra-ethnic and religious tensions testing the identifications and affiliations of young people living and learning in contemporary Hpa-an.

Keywords: Temporal Mobilities
Democratic Transition
Migration
Aspiration &amp; Agency
(International) Development
Karen Peoples
Social Navigation
Southeast Asia
Youth Mobility
Burma/Myanmar
Ethnography
(Non-State) Education
Socio-Spatial Mobilities
Advisor: Chatty, D
Unjust enrichment claims & countervailing obligations

This thesis investigates the relationship between unjust enrichment claims and countervailing legal entitlements of the defendant. It examines the cases that deny restitution on the basis that the enrichment was owed to the defendant under a valid legal obligation. The authorities suggest that there are two separate rules that perform this function: ‘the good consideration rule’ and the ‘legal obligation qualification’.
This thesis argues that the good consideration rule is best explained as an enrichment qualification. The ‘consideration’ provided by the defendant offsets the enrichment received. In net terms, this leaves the defendant in an enrichment-neutral position.
The legal obligation qualification is more difficult to account for. Most academic explanations of this rule are based on the assumption that unjust enrichment is subsidiary to other legal obligations. However, no convincing reasons have been offered to support a general doctrine of subsidiarity in the English law of unjust enrichment. The thesis argues that in order to explain the legal obligation qualification one must ask two principal questions: what are the normative reasons that justify unjust enrichment claims? Does the presence of a countervailing legal entitlement defeat any of these reasons?
In view of the uncertainty relating to the normative justification for unjust enrichment, this thesis uses two prominent theoretical accounts as its framework: the entitlement thesis and corrective justice theory. On either view, it is argued, the legal obligation qualification can be explained by the need to maintain equality between the claimant and the defendant.
The equality explanation has many implications for the operation of the legal obligation qualification. For instance, it confirms that the rule operates by denying primary liability. It is suggested, therefore, that the legal burden on this point must fall on the claimant. More importantly, the justificatory scope of the equality thesis extends to cases that have, thus far, been treated as instances of application of the good consideration rule. For the future, therefore, it is suggested that the language of ‘good consideration’ must be abandoned.

Keywords: Restitution
Enrichment owed
Good consideration
Unjust enrichment
Advisor: Stevens, R
The Vajramahābhairavatantra: Its origins, intertextuality, and transmission

This thesis focuses on the Vajramahābhairavatantra, a seminal Buddhist tantra dedicated to the fear-inducing buffalo-headed Buddhist tantric deity Vajrabhairava (rdo rje ’jigs byed). The tantra has survived to us through Sanskrit manuscripts, which have not previously been investigated. My project intends to fulfill this desideratum by providing the first-ever edition of the Sanskrit text of the Vajramahābhairavatantra and by reconstructing its missing parts from the Sampuṭatantra. Apart from the establishment of a critically edited version of the text and the production of an English translation, my thesis studies the contents in the light of relevant sources outside the corpus, such as early Śaiva and Buddhist tantras like the Niśvāsatattvasaṃhitā, the Mañjuśriyamūlakalpa, but also of sources within the corpus, such as the six canonical commentaries on the difficult points of the root-text. My focus on the intertextual relations between the Vajramahābhairavatantra and other early tantras, as well as the close analysis of the tantra’s Indian exegetical tradition that has survived uniquely through the Tibetan canon, the Bstan ’gyur is important for our understanding of the origin and development of the Vajrabhairava cult. While sufficient scholarly attention has been paid to comparatively late milieus, such as the Chinese, Tibetan, and Mongolian instantiations, the early Indian cradle has been neglected. The aim of my thesis is to demonstrate that the Vajrabhairava cult can be located within the cultural framework of early tantric magic, and thus contains elements that point back to an earlier period than what had been assumed so far. Besides uncovering the intertextual and intellectual relationships between Śaiva and Buddhist tantric traditions, my thesis investigates the appropriation and consolidation of the tantra in Tibet, especially through a reconstruction of the lineages that took part in its transmission from India to Tibet in the light of existing Tibetan historiographies. It thus contributes to our understanding of the appropriation of Indic Buddhist traditions on the Tibetan plateau.

Keywords: tantric magic
Vajrabhairava
Advisor: Roesler, U
Acharya, D
Assessing the mechanistic synergy between cancer virotherapy and external beam radiation

One of the core radiobiological features determining response to fractionated treatment is repair of ionising radiation-mediated damage. Adenoviruses are shown to inhibit the DNA damage response (DDR), in particular the pathways involved in repairing double-strand DNA breaks. Combination treatment with radiation and oncolytic adenoviruses therefore offers the potential for tumour-targeted radiosensitisation, and even synergy.
Oncolytic adenovirus treatment is frequently limited to intratumoural delivery, restricting treatment to directly-accessible cancers. Enadenotucirev (EnAd), a Group B chimeric oncolytic adenovirus, has been shown to localise to a number of different tumour types following intravenous delivery. EnAd may therefore allow treatment of patients with visceral and widespread metastatic disease. We hypothesised that combination therapy with EnAd and radiation may lead to synergistic cytotoxicity, and aimed to explore potential underlying mechanisms.
We demonstrated EnAd- and adenovirus serotype 5 (Ad5)-mediated inhibition of the DDR at multiple points along the pathway. Adenovirus infection resulted in decreased 53BP1 and RAD51 foci formation following irradiation, and reduced DNA ligase IV levels. Interestingly, EnAd and Ad11p, but not Ad5, caused phosphorylation of 53BP1 even in the absence of irradiation. Irradiation enhanced infectious particle production of EnAd, but not Ad5 or Ad11p, in vitro, and likewise caused increased EnAd production and transgene expression in vivo. We propose that these results are at least partially due to radiation-mediated enhanced expression of viral E1A. Treatment synergy was indeed seen in vitro in cells irradiated prior to EnAd infection, and irradiation of xenografts following EnAd treatment in vivo resulted in significant tumour growth delay when compared to animals receiving PBS prior to radiation.
Our results were consistent with synergistic cytotoxicity in vitro, and radiosensitisation in vivo, using EnAd and radiation combination therapy. This is likely due to a combination of enhanced oncolytic virus production and increased radiation-induced cytotoxicity following DNA damage repair inhibition. Our findings provide further support for the phase 1 Chemoradiation with Enadenotucirev as a Radiosensitiser in locally Advanced Rectal cancer (CEDAR) trial, which is now recruiting.

Keywords: Virology
Radiosensitisation
Radiotherapy
Oncolytic virotherapy
Oncology
Combination therapy
Enadenotucirev
DNA damage
Virotherapy
Oncolytic virus
Ionizing radiation
Oncolytic
Advisor: Seymour, L
Higgins, G
Lei-Rossmann, J
A GPU parallelised multimodal registration framework for improved anatomical consistency

Biomedical image registration is well established as a core component of most neuroimaging processing pipelines. It allows multiple subjects to be analysed using a common frame of reference, thereby facilitating both the localisation and quantification of similarities and differences between individuals or population groups.
An assumption inherent to such analyses is that registration produces a one-to-one mapping between common anatomical locations across subjects. Errors in image registration violate this assumption, typically reducing both the power to detect effects of interest and the ability to localise those effects. But image registration is an inherently ill-posed problem, and therefore the true, unique one-to-one mapping can generally never be found (if it even exists). Instead, registration methods can only attempt to produce the most likely deformation, given the subject data and models of what type of mappings are more probable than others.
In this thesis I present two approaches to improving the accuracy of nonlinear registration, particularly in the context of magnetic resonance imaging of the brain.
The first utilises a computationally complex regularisation model which penalises the stretching effect of a deformation in a highly nonlinear way. The method produces more anatomically plausible mappings, with less distortion of both volume and shape, when compared to current state-of-the-art methods. It achieves this while simultaneously equalling or bettering the alignment accuracy, as measured by the overlap of expert-segmented anatomical brain regions.
The second leverages the fact that it is increasingly common for both scalar and tensor imaging modalities, containing complementary spatial information, to be acquired for each subject in a dataset. The similarity between multiple modalities are then simultaneously compared, accounting for differences in both tissue location and orientation, to better inform the registration in a data-driven way. This leads to a measurable and significant improvement in anatomical consistency across subjects, evaluated using group-level task-based brain activation maps.
The cost associated with these improvements is an increase in algorithmic complexity. This is addressed by leveraging the massively parallelised computing capabilities of graphics processing units to offset the rise in complexity. To this end, I present my implementation of a new software tool, the MultiMOdal Registration Framework (MMORF), which forms the basis of all of the results herein.
My hope is that the benefits I present in this thesis will allow MMORF to have a real impact in unifying volumetric image registration in the field of neuroimaging.

Keywords: Nonlinear registration
Image registration
Nonlinear optimisation
Multimodal
GPU acceleration
Magnetic resonance imaging
Neuroimaging
Advisor: Andersson, J
Smith, S
Fluorescent nanodiamonds for nanosensing and single-molecule imaging

Unlike ensemble measurements where individual behaviours are averaged and therefore inaccessible, single-molecule microscopy allows researchers to obtain real-time information about a biomolecule's intracellular localisation, interactions or conformational changes. The observation time of individual biomolecules, typically a few seconds to a few minutes, depends on the photostability of the fluorescent molecules used as imaging probes. The limitation of the observation time prevents us to gain precious insight on long-term individual biomolecular behaviours as biological processes like bacterial cell division take at least 20 minutes to occur.
The fluorescent nitrogen-vacancy defect in nanodiamond (ND) can emit light for hours and is an established nanoscale probe for quantum sensing (e.g., magnetometry); as a result, there has been much interest in using NDs in biological imaging. Nevertheless, the implementation of fluorescent NDs (FNDs) in single-molecule imaging has been limited by the lack of single-molecule characterisation methods and the low brightness of 10-nm FNDs.
In this thesis, we first report the development of a photophysical characterisation method for FNDs down to 5-10 nm in size and present the discovery of the 10-nm ND's potential as direct pH nanosensors. We then pursue the establishment of a new characterisation technique for diffusing NDs and describe an innovative routine to estimate the proportion of FNDs among all the NDs. An optimised biofunctionalisation approach is detailed, thus allowing us to perform in vitro single-molecule work with the smallest conjugated FNDs ever manufactured (10-15 nm). Finally, we explore the application of these small functionalised FNDs for quantum sensing and present in vivo experiments using conjugated FNDs in bacteria.

Keywords: photophysics
diamond
biophysics
nitrogen vacancy centre
colloidal stability
ph sensing
microscopy
fluorescence
nanoparticles
surface chemistry
single particle tracking
nanodiamond
single molecule imaging
NV centre
nanosensing
aggregation
Analytic bootstrap for perturbative conformal field theories

Conformal field theories (CFTs) play a central role in theoretical physics with many applications ranging from condensed matter to string theory. The conformal bootstrap studies conformal field theories using mathematical consistency conditions and has seen great progress over the last decade. In this thesis we present an implementation of analytic bootstrap methods for perturbative conformal field theories in dimensions greater than two, which we achieve by combining large spin perturbation theory with the Lorentzian inversion formula. In the presence of a small expansion parameter, not necessarily the coupling constant, we develop this into a systematic framework, applicable to a wide range of theories.
The first two chapters provide the necessary background and a review of the analytic bootstrap. This is followed by a chapter which describes the method in detail, taking the form of a practical guide to large spin perturbation theory by means of a step-by-step implementation. The goal is to compute the CFT-data that define a given conformal field theory, and this is achieved by considering contributions from operators in a four-point correlator through the crossing equation. We give a general recipe for determining which operators to consider, how to find their contributions from conformal blocks and how to compute the corresponding CFT-data through the inversion formula.
The second part of the thesis presents several explicit implementations of the framework, taking examples from a number of well-studied conformal field theories. We show how many literature results can be reproduced from a purely bootstrap perspective and how a variety of new results can be derived. We consider in depth how to determine the CFT-data in the ε expansion for the Wilson-Fisher model from crossed-channel operators. All CFT-data to order ε follow from only the identity and the bilinear scalar operator, and by considering contributions from two infinite families of operators we generate new results at order ε4. We study in similar depth conformal gauge theories in four dimensions, where we find a five-parameter solution for the most general form of the one-loop four-point correlator of bilinear scalars. For particular parameter values this reproduces the case of the Konishi operator and the stress tensor multiplet in weakly coupled Ν=4 super Yang-Mills theory. We then present more briefly four additional examples. These include the critical O(N) model in a large N expansion, a solution for φ4 theory with any global symmetry, multicritical theories to order ε2 near their critical dimensions, including new results for the central charge, and the four-point correlator of bilinear scalars in the ε expansion. We conclude the thesis with a discussion and some appendices.

Keywords: Conformal field theory
Conformal bootstrap
Advisor: Alday, LF
Contributions to Bayesian Nonparametric methods with applications

The Bayesian methodology provides a compelling framework that offers an intuitive yet practical approach to model the world, allowing refinement of the statistician’s prior knowledge in light of incoming empirical data. Any unknown quantity is regarded as random, and its updated knowledge, called the posterior distribution, quantifies the remaining uncertainty therein. The choice of the prior distribution is at the core of Bayesian modeling and plays a primary role in the model’s performance. Bayesian Nonparametric (BNP) modeling utilizes infinitely many parameters to capture intricate patterns of real-world phenomena and adapts to the complexity of the data.
Bayesian Nonparametrics is, therefore, an appealing tool that has found many successful applications in a large variety of domains such as machine learning, ecology, biology, finance, etc. Our research focus is on modeling and analyzing discrete structures, with a particular interest in the context of clustering and feature allocation. In the first introductory chapter we review the necessary theoretical background and present the critical building blocks for the constructions proposed in the following chapters. The fist part of this dissertation is dedicated to modeling complex data with Bayesian Nonparametrics. Our objective is to overcome the limitations of existing approaches and describe models that can capture real-world characteristics. We pay careful attention to power-law properties, which seem to be ubiquitous in real-world applications, and propose models for networks with community structures, clustering, and financial time-series. In the second part, we move beyond modelling purposes and show that Bayesian nonparametric can offer powerful tools for the theoretical analysis of (non-Bayesian) estimation problems. The part is dedicated to the question of rare events and missing mass estimation in the species sampling and feature allocation frameworks. Using carefully chosen Nonparametric priors, we show the nonexistence of universally consistent estimators of the missing mass. We also derive lower bounds on rates of estimation of rare events under appropriate assumptions.

Advisor: Caron, F