VictorJuiz/thesis huggingface dataset:
Ben Ali's Tunisia: interncine struggles and the rise of contention in a party-state, 1987-2011

The 2010–11 Arab Spring caught scholars and regional experts, who had long been invested in explaining the apparent stability of regimes in the Middle East and North Africa, completely off guard. To account for the speed and suddenness with which several authoritarian regimes collapsed, many such scholars have since focused their research on the popular revolts and on people’s calls for dignity, freedom, and democratic politics. Yet the fall of dictatorships, some of which were considered amongst the world’s most stable, may stem at least as much from factors internal to these regimes themselves. My doctoral thesis indeed suggests that internal grievances, power struggles, and the rise of dissent and contention within regime ranks were key reasons behind the collapse of these dictatorships. It argues that the political and economic marginalisation of the dictators’ own constituencies – often a decades-long process – is a critical factor behind their downfall. My dissertation focuses on the regime of Zine el-Abidine Ben Ali in Tunisia, from 1987 when he took power until he was ousted in 2011. It analyses the role of the ruling Constitutional Democratic Rally (RCD) party in his quest for dominance. I show that during Ben Ali’s initial consolidation of power he widened the structures of the RCD to enlarge his support base, later ruling through a narrower core to embark upon increasingly personalised politics. In the 2000s Ben Ali’s succession became a critical topic and some of his relatives integrated into the RCD in hope of preparing for a successor from within the family, a trend which marginalised many longtime activists and led them increasingly to defy the ruling clique. When mass protests erupted in December 2010 these sidelined sections within the RCD decided to display their discontent in the open. Those I call ‘party losers’ became dissenters, and their political contention took various forms: the rank and file typically joined the protest movement, whereas midlevel officials and some senior leaders engaged in passive acts of resistance. Their political contention divided the party – the President’s most important support base – and drove even loyal activists underground, thus depriving the party of its capacity to stage counter-mobilisations and displaying publicly the fragmentation of the regime. This provided a political opening for sections within the elite to move against Ben Ali. Indeed, contrary to the commonly accepted narrative that Ben Ali ‘fled’ Tunisia because of the mass protests, I show that he was ousted following a secret coup d’état from within his own regime, which occurred amidst the demonstrations.

Advisor: Willis, M
Beam model of Doppler backscattering: theory and experiment

We use beam tracing --- implemented with a newly-written code, Scotty --- in combination with the reciprocity theorem to derive a model for the linear backscattered power of the Doppler Backscattering (DBS) diagnostic. Our model works for both the O-mode and X-mode in tokamak geometry (and certain regimes of stellarators). We present the analytical derivation of our model and its implications on the DBS signal localisation and the wavenumber resolution. To determine these two quantities, we find that it is the curvature of the field lines and the magnetic shear that are important, rather than the curvature of the cut-off surface. We proceed to shed light on the hitherto poorly-understood quantitative effect of the mismatch angle. Armed with this knowledge, we analyse MAST DBS data for various frequency channels and at various times, demonstrating that the beam model can indeed properly account for the mismatch attenuation. Interestingly, we show that mismatch attenuation can have a significant effect on localisation, shifting it away from the cut-off. Consequently, one can use this model to correct for the attenuation due to mismatch and its effect on localisation, avoiding the need for empirical optimisation. This is especially important in spherical tokamaks, since the magnetic pitch angle is large and varies both spatially and temporally.

Keywords: tokamaks
stellarators
plasma diagnostics
Doppler reflectometry
Doppler backscattering
Advisor: Parra Diaz, F
Small molecule organic acceptors: relating chemical structure with thin film device performance

The development of the class of small molecule organic semiconductors typically referred to as non-fullerene acceptors (NFA), has led to a resurgence of research interest on the topic of organic photovoltaic (OPV) devices, in which they have replaced fullerene derivatives as the electron acceptors of choice. This thesis contributes to understanding the relationship between the chemical structure of these small molecule organic semiconductors, their physical properties, optoelectronic properties, and performance in organic electronic thin film devices. A better understanding of this relationship is required to direct the development of novel small molecule organic semiconductors.
In the first part of this thesis the impact of aliphatic side chains on NFA intermolecular packing and mobility is investigated. The NFA O-IDTBR, which has been widely used in OPV applications, is also found to be a good candidate for organic thin film transistor (OTFT) applications. The high mobility of over 0.4 cm2 V-1 s-1 achieved in OTFTs operating in the saturation regime is attributed to O-IDTBR’s packing motif in the solid state. In the second part of the thesis further chemical structure modifications to O-IDTBR’s conjugated push-pull donor-acceptor structure as well as its aliphatic side chains are investigated. Through these structural modifications, the unique properties that the combination of the specific conjugated chromophore and octyl side chains present in O IDTBR have given the material, allowing it to deliver high mobilities in OTFTs, are highlighted.
The third part of this thesis focuses on organic photodetectors (OPD), a relatively recently explored application for NFAs. Very little is currently known about the impact of OSC chemical structure on OPD performance metrics. In particular, achieving a low dark current at reverse bias has been a major limitation to the development of OPD technology. Two new blends based on NFAs for OPDs, PTQ10:O-FBR and PTQ10:O-IDTBR, are identified as delivering low dark current densities at reverse bias, resulting in high specific detectivities of over 1012 Jones.
The final part of the thesis focuses on NFAs with chemical structures tuned to allow absorption in the NIR region. Whilst OPVs were originally touted as a low-cost alternative to other solar cell technologies, the reduction in the cost of manufacturing silicon based solar panels has meant that, for OPV to realise its market potential, other advantages over competing solar technologies need to be exploited. One such application is transparent and semi-transparent photovoltaics for which near-infra red (NIR), or specifically visible blind, NFAs are being developed. Similarly, a key OPD application is for detectors targeting NIR absorption, which have uses in biomedical imaging, substance identification and optical communications. The final results chapter explores the properties of several NIR absorbing NFAs and their application in both OPV and OPD applications.

Advisor: McCulloch, I
Non-equilibrium dynamics in two-dimensional quantum systems

The understanding and precise prediction of non-equilibrium quantum many-body dynamics, in particular across a critical point, remains a difficult task due to the relevance of all length scales near the critical point. Furthermore, the number of parameters required to characterise the state of the system increases exponentially with the number of particles, making the numerical investigation of such a system extremely difficult.
In this thesis, we use ultracold 87Rb atoms prepared in a bilayer two-dimensional (2D) trap to probe the Berezinskii-Kosterlitz-Thouless (BKT) phase transition in detail, both in and out of equilibrium. These experiments use a multiple-radiofrequency dressed trap, which allows dynamical control of the trapped atoms as well as the precise determination of the many-body wavefunction. For the characterisation of the 2D Bose gases using matter-wave interferometry, a novel technique was developed to obtain high contrast fringes by selective imaging of slices of the atomic cloud. This allows the observation of local fluctuations, such as phase correlation function, local vortex density and coherence full counting statistics. Utilising these observables, we have identified the BKT critical point and characterised microscopic features of harmonically-trapped 2D Bose gases in equilibrium. With this information about the system, we probe the non-equilibrium dynamics of 2D Bose gases following a quench across the BKT critical point. The system is quenched by a coherent splitting, which introduces a sudden reduction of density resulting in the quench from the superfluid to the thermal phase. We monitor the dynamics towards the vortex-proliferated state and find that the vortex-unbinding dynamics is well described by the real-time renormalisation group theory. Finally, we show preliminary results for a tunnel-coupled bilayer 2D gas, in which we probe the oscillations of the relative phase of the two layers of the superfluid.
The results presented in this thesis demonstrate that the multiple-RF dressing technique is a very powerful tool for investigating quantum many-body phenomena. This paves the way for future studies of non-equilibrium critical dynamics and their description with renormalisation-group theory.

Keywords: Renormalisation-group theory
Matter-wave interferometry
Ultracold atoms
Berezinskii-Kosterlitz-Thouless transition
Spin squeezing
Bose-Einstein condensate
Advisor: Foot, C
Backbone-modified oligonucleotides for biology and medicine 

Chemically modified oligonucleotides find myriad applications in therapeutics and synthetic biology because they can be utilised to modulate biophysical or therapeutic properties, install fluorophores for detection, or to allow orthogonal reactivity through additional functional groups. Whilst oligonucleotides can be principally modified anywhere at their nucleotide subunits, the presented work investigates modifications of the oligonucleotide backbone for therapeutic applications and synthetic biology.
Antisense oligonucleotides (ASOs) have become an emerging therapeutic approach to modulate protein expression at the mRNA level to combat hard-to-treat diseases. Stability against nucleolytic degradation, good target hybridisation properties, and efficient delivery into the cell are essential. The chemical modification of the hydrolysable, anionic phosphodiester backbone holds great potential for protection against phosphodiesterases, and to reduce the polyanionic charges for enhanced cellular uptake. In the presented work, two charge-neutral backbone surrogates—the carbamate and amide internucleoside linkages—were investigated for their ability to confer drug-like properties by replacing the natural phosphodiester backbone. Combinations with additional bicyclic sugar modifications and different designs of the ASO segments were explored. The antisense assessment criteria comprised their general hybridisation properties with an RNA target, their stability against nucleolytic degradation, and their potential for enhanced cellular uptake.
Backbone-modified oligonucleotides are also versatile constructs for synthetic biology as exemplified by the construction of synthetic genetic polymers, ribozymes, aptamers, or gene editing systems. Amongst those, artificial genetic polymers can be applied for gene synthesis, sequencing, or the production of nanomaterials. A crucial element for backbone modifications in genetic templates is their compatibility to be read by polymerases. In this context, triazole-based internucleoside linkages have been extensively studied as promising replication compatible phosphodiester mimics. This thesis presents a novel triazole backbone structure and its assessment for replication compatibility in terms of continuation, speed, and correctness of the read-through by DNA polymerases.

Keywords: Oligonucleotides
Antisense Oligonucleotides
Nucleic Acids
Advisor: Brown, T
Fluid-walled microfluidics for cell migration studies

Microfluidic systems have evolved significantly over the past decade to offer biologists in vitro environments that mimic organ function, enable disease modelling, and perform high-throughput drug screens. Despite these important advances, microfluidic uptake in biomedical research remains limited, with the main reasons cited being biocompatibility concerns, technical complexity, and low flexibility of systems. Recently, an alternative approach to traditional microfluidics was developed, which uses only the materials common to biologists. The technique, termed fluid-walled microfluidics, shapes cell culture media on Petri dishes in a variety of methods and has been extensively studied in static environments, using chambers resembling sessile drops to perform various cell-based assays. However, studies involving flow have remained limited to proof-of-concept applications. As flow regulates many biological behaviours, it is essential to incorporate flow in fluid-walled microfluidic assays to make these accessible to the wider biomedical community.
This thesis explores the underlying properties of fluid-walled systems to establish and experimentally validate a simple mathematical model of circuits experiencing flow, and applies it to study complex cell migration behaviours. A method for real-time isolation and retrieval of specific sub-populations of cells in flowing environments is then introduced, using 3D-printed adaptors to convert microscopes into micromanipulators that reconfigure circuits, and applied to study both mammalian and bacterial cell migration in response to various concentration gradients (chemotaxis). Finally, a general approach for chemotaxis studies is presented, using both passive and active circuits (with/without flow) to give users flexibility and control over defined experimental conditions. Altogether, this thesis serves as a blueprint for the fabrication and manipulation of open and flowing microfluidic circuits using only Petri dishes, cell culture media, FC40, a 3-axis traverse and syringe pumps. The methods outlined empower biologists to study complex cellular behaviours in environments that more closely mimic in vivo conditions, with the aim of making microfluidic technology accessible to the less experienced user.

Keywords: microfluidics
chemotaxis
fluid walls
Advisor: Walsh, E
The effect of blood glucose selfmonitoring in patients with non-insulin treated type 2 diabetes

Significant debate exists about the utility of blood glucose self-monitoring (BGSM) in patients with non-insulin treated type 2 diabetes. Previous studies lacked any theoretically based intervention and produced conflicting results. The novel randomized controlled trial reported in this thesis used a theoretically based intervention to evaluate the effectiveness of BGSM as a strategy of glycaemic feedback to promote self management.
Psychological theory was used to develop an intervention to support use of glycaemic feedback to promote self-management. Measures based on similar psychological theory were also developed to assess the effectiveness of the intervention in targeting the hypothesized mediators of behaviour. Participants were randomized to one of three intervention arms: regular HbA1c, BGSM with facilitator interpretation and BGSM with patient interpretation and application.
There was no significant difference in HbA1c between the three groups after one year (p=0.653), although significant reductions were noted in all groups in patients with HbA1c over 8%. There were no significant differences in secondary clinical outcomes of change in weight (p=0.649) or systolic or diastolic blood pressure (p=0.890 and p=0.860 respectively). Significant changes in beliefs and behaviour were limited to change in illness coherence (p=0.041) and in eating high fat diets (p=0.009) and five portions of fruit and vegetables daily (p=0.017).
Semi-structured qualitative interviews were used to explore patients' experiences and perceptions of BGSM. Participants who had difficulty in adhering to self-management recommendations found BGSM helpful, whereas those who had previously followed recommendations were discouraged by BGSM results if they did not reflect their efforts.
BGSM with patient interpretation and application did not significantly improve HbA1c or other clinical parameters when compared to BGSM with facilitator feedback or regular HbA1c measurement. It also had little effect on illness beliefs and self-reported behaviour. It did, however, appear to be beneficial in patients who had difficulty in following self-management recommendations.

Advisor: Neil, A
Farmer, A
Towards effective, efficient and equitable privacy-preserving machine learning

Machine learning has assumed an increasingly important role in Artificial Intelligence in recent years. Moreover, in spheres such as online shopping, virtual personal assistants, recommendation systems amongst other things, it is quickly becoming part and parcel of our daily lives. The power of data combined with machine learning algorithms has driven widespread uptake of these AI methods. However, there have been sensitivity and privacy concerns over the data to be processed. This is especially salient in areas such as healthcare and finance. Privacy-preserving machine learning mitigates these privacy challenges through private computation over sensitive data. However, the process is not trivial or without trade-offs.
In this thesis, we focus on designing effective and efficient protocols for facilitating end-to-end privacy-preserving machine learning, particularly for neural network training and inference. We primarily focus on multi-party computation alongside non-cryptographic primitives such as federated learning for private computation. We start with designing QUOTIENT, an efficient two-party secure training and prediction framework. QUOTIENT benefits from the holistic adaptation of standard neural network training into a crypto-friendly training process alongside a customized hybrid MPC protocol for secure computation. Next, we introduce federated learning to support highly decentralized training over unlabeled data. We motivate the idea of `silos' to ensure superior privacy and isolation across sub-groups. To complete the technical contribution, we propose an MPC-friendly covertly secure commitment scheme for enabling certified predictions. More specifically this helps to enforce non-functional constraints such as fairness, interpretability, and safety over trained models at the time of inference, making the process more equitable. We design, implement and benchmark all of these frameworks to show performance gains in computation, communication and accuracy. We conclude the thesis with a user study focused on enhancing usability, efficiency, assisting in design and helping ensure equity in privacy-preserving computation frameworks at large. This study takes the form of semi-structured interviews with various stakeholders in the privacy-preserving computation ecosystem.
We improve upon the state of the art by more than an order of magnitude in speed, for our protocols, alongside significant gains in accuracy and communication. The user study presents a rich socio-technical perspective to the purely technical contributions. The combination of theory, practice and evaluation, in this thesis, acts as a multi-perspective framework for motivating design, development and further research in effective, efficient and equitable privacy-preserving machine learning.

Keywords: privacy-enhancing technologies
committed MPC
secure multi-party computation
privacy-preserving deep learning
quantized deep neural networks
Advisor: Shadbolt, N
Needs in the philosophy of history : Rousseau to Marx

The thesis examines the role of the multiplication of human needs, the desires associated with them, and the capacities developed by human beings to satisfy those desires, in the philosophies of history of Rousseau, Kant, Hegel and Marx.
It presents an interpretation of Rousseau in which the historical multiplication of needs is both generated by and generates the development of amour-propre. In turn the development of amour-propre is necessary in order for human beings to develop the virtue of justice, and to participate as citizens in the society of the Social Contract.
It argues that in Kant’s philosophy of history the expansion of needs and their associated desires, and the development of the means to satisfy them, brings about a ‘culture of skill’. This in turn leads to the development of just civil societies and of the ‘culture of discipline’. These together constitute the ‘ultimate end of nature’: that naturally produced circumstance which can maximally facilitate the moralisation of mankind.
It interprets sections of Hegel’s systematic account of mind as providing a philosophical history of ordinary human motivation, in which the ‘desire’ of the isolated human being is superseded successively by the ‘needs’ of the person, the ‘social needs’ of the member of a civil society, and the ‘duties’ of the citizen of the modern state. This history provides an underpinning for Hegel’s official account of history as the rise and fall of successive civilisations.
It argues that in Marx’s early writings history is conceived as the development through private exchange of those needs, activities and products which are characteristically human, but in an ‘estranged’ shape which can only be overcome by the final abolition of private exchange itself. This conception of history survives in Marx’s later writings and provides a basis for understanding direct producers’ motivations for overthrowing a social form as derived from a sense of incompatibility between their conception of self and the economic relations under which they live. Marx’s ‘moral’ condemnations of capitalism are understood in the light of this model of revolutionary motivation.
It is concluded that in each of these thinkers the process of multiplication of needs and their associated desires plays a central role in a conception of history as a process culminating in the establishment of the ‘good society’, and thus in humanity’s self-realisation. It thereby plays an important though under-recognised role in the social and political thought of each of them.

Keywords: philosophy
need
Rousseau
Marx
History