VictorJuiz/thesis huggingface dataset:
Generic insistence: Joseph Conrad and the document in selected British and American modernist fiction

This thesis explores the citation of documents in the modernist novel. From contracts to newspaper articles, telegrams to reports, documents are invoked as interleaved texts in ways that, to date, have not been critically interrogated. I consider a range of novels, including works by Ford Madox Ford, Virginia Woolf, Nella Larsen, and Willa Cather, which are selected, in part, as a litmus of Anglo-American modernism, though they can more productively also be understood as coalescing around the example set by Joseph Conrad. Replete with allusions to documents, Conrad’s oeuvre is developed across the thesis as a meta-commentary on the document in modernist literature. In placing the document at the centre of analysis, and in using Conrad as a diagnostic of the document in modernity, the manifold ways in which authors use interpolated texts to perform denotative and connotative “work” in their narratives emerge, with the effect of revising our understanding of documents. These authors reveal the power of mass produced documents to lay claim to novelistic language; the historical role of documents in reifying inequality; on the level of narrative, the thematic potential of the document as a reiterable text; and finally, the capacity of the document, in its most depersonalized form, to realize social collectivity and community. This project therefore asks us to rethink and relocate the document as central to the modernist novel.

Keywords: modernism
empire
archive
Joseph Conrad
Ford Madox Ford
Nella Larsen
Willa Cather
documents
Virginia Woolf
Advisor: Boehmer, E
Critical properties of random systems

Calculations are presented for a series of interrelated problems in the theory of disordered solids.
The simple mean field theory of tricriticality in the layered Ising metamagnet is modified by inclusion of the Bethe-Peierls equation of state for the planar interactions. The approximation allows for a model of dilution with a finite percolation concentration for the layers. The calculated behaviour as a function of dilution for anisotropic coupling strengths allows comparison with experimental results on dilute ferrous chloride. Estimation is made of the effects of treating fluctuations by theories with mean field singularities.
A discussion is given of first order phase transitions in disordered systems. A mean field theory of the implications of introducing quenched disorder to a system undergoing a transition of first order is effected by reformulating the problem in terms of a translationally invariant one via the replica method. The conclusions are examined in terms of a simple scaling theory and criteria derived for smearing of the singularities.
Dynamic and thermodynamic properties of diluted magnetic insulators near the percolation concentration are considered in terms of simple geometric models of the percolating cluster as introduced by de Gennes. New scaling relations for the spin wave stiffness and conductivity exponents are derived and differences from previous relations interpreted geometrically.
The scaling models of the percolating cluster so found, in which correlations propagate locally via effectively one-dimensional paths, are applied to the determination of the mobility edge for spin wave excitations in a dilute Heisenberg magnet near the percolation threshold. A prediction for the functional form of the mobility edge is made by means of results known for the Anderson model and a localisation length derived from an exact solution of a random problem by Dyson.

Advisor: Elliott, R
Algorithms for polynomial and rational approximation

Robust algorithms for the approximation of functions are studied and developed in this thesis. Novel results and algorithms on piecewise polynomial interpolation, rational interpolation and best polynomial and rational approximations are presented.
Algorithms for the extension of Chebfun, a software system for the numerical computation with functions, are described. These algorithms allow the construction and manipulation of piecewise smooth functions numerically with machine precision. Breakpoints delimiting subintervals are introduced explicitly, implicitly or automatically, the latter method combining recursive subdivision and edge detection techniques.
For interpolation by rational functions with free poles, a novel method is presented. When the interpolation nodes are roots of unity or Chebyshev points the algorithm is particularly simple and relies on discrete Fourier transform matrices, which results in a fast implementation using the Fast Fourier Transform. The method is generalised for arbitrary grids, which requires the construction of polynomials orthogonal on the set of interpolation nodes. The new algorithm has connections with other methods, particularly the work of Jacobi and Kronecker, Berrut and Mittelmann, and Egecioglu and Koc.
Computed rational interpolants are compared with the behaviour expected from the theory of convergence of these approximants, and the difficulties due to truncated arithmetic are explained. The appearance of common factors in the numerator and denominator due to finite precision arithmetic is characterised by the behaviour of the singular values of the linear system associated with the rational interpolation problem.
Finally, new Remez algorithms for the computation of best polynomial and rational approximations are presented. These algorithms rely on interpolation, for the computation of trial functions, and on Chebfun, for the location of trial references. For polynomials, the algorithm is particularly robust and efficient, and we report experiments with degrees in the thousands. For rational functions, we clarify the numerical issues that affect its application.

Keywords: Chebyshev polynomials
Chebfun
best approximation
interpolation
Advisor: Trefethen, L
Coupled fluctuations of blood pressure and heart rate time series

The human cardiovascular system governs the heart rate and blood pressure. A neural sensor called the baroreceptor is controlled by the the blood pressure; the sensitivity of its reflex is important in determining the cause of hypertension. This sensitivity may be obtained from the coupled fluctuations of blood pressure and heart rate time series. However, the current method used assumes locally linear coupling of the heart rate and blood pressure, which has been shown to be nonlinear. In this dissertation we apply this current method to sample data, investigate improvements and, having gained further insight into the cardiovascular system from models of the system, offer an alternative method of measuring the baroreceptor relex sensitivity.
Tissue interaction and spatial pattern formation

The development of spatial structure and form on vertebrate skin is a complex and poorly understood phenomenon. We consider here a new mechanochemical tissue interaction model for generating vertebrate skin patterns. Tissue interaction, which plays a crucial role in vertebrate skin morphogenesis, is modelled by reacting and diffusing signal morphogens. The model consists of seven coupled partial differential equations, one each for dermal and epidermal cell densities, four for the signal morphogen concentrations and one for describing epithelial mechanics. Because of its complexity, we reduce the full model to a small strain quasi-steady-state model, by making several simplifying assumptions.
A steady state analysis demonstrates that our reduced system possesses stable time-independent steady state solutions on one-dimensional spatial domains. A linear analysis combined with a multiple time-scale perturbation procedure and numerical simulations are used to examine the range of patterns that the model can exhibit on both one- and two-dimensions domains. Spatial patterns, such as rolls, squares, rhombi and hexagons, which are remarkably similar to those observed on vertebrate skin, are obtained.
Although much of the work on pattern formation is concerned with synchronous spatial patterning, many structures on vertebrate skin are laid down in a sequential fashion. Our tissue interaction model can account for such sequential pattern formation. A linear analysis and a regular perturbation analysis is used to examine propagating epithelial contraction waves coupled to dermal cell invasion waves. The results compare favourably with those obtained from numerical simulations of the model. Furthermore, sequential pattern formation on one-dimensional domains is analysed; first by an asymptotic technique, and then by a new method involving the envelopes of the spatio-temporal propagating solutions. Both methods provide analytical estimates for the speeds of the wave of propagating pattern which are in close agreement with those obtained numerically. Finally, by numerical simulations, we show that our tissue interaction model can account for two-dimensional sequential pattern formation. In particular, we show that complex two-dimensional patterns can be determined by simple quasi-one-dimensional patterns.

Advisor: Murray, J
Maini, P
Magneto-optical studies of semiconductor heterostructures

This thesis is primarily concerned with far infrared effects in semiconductor heterostructures. These properties have been studied as a function of magnetic fields at low temperature using various optical detection techniques. Cyclotron resonance has been studied in CdTe quantum wells. The results are compared with calculations using the memory function approach, which demonstrate that there is a large reduction in the resonant coupling due to level occupancy effects. Semimetallic GaSb/InAs superlattices have been studied by cyclotron resonance experiments. In samples with low InAs/GaSb ratios (~1), a pinning between the heavy hole subbands is predicted by theory which results in a suppression of heavy hole resonance at high magnetic fields. Photoluminescence measurements on a series of ultra-high mobility GaAs/AlGaAs heterojunctions have been performed. It has been found that the modulation caused by far infrared beam is entirely dependent on the filling factors, which is understood as the Landau level coupling effects between the subbands of 2DES. A GaAs/AlGaAs coupled quantum well photodiode has been studied by photoluminescence and photocurrent under the influence of far infrared beam. An enhancement of the photocurrent in the device is observed when the infrared photons are resonant with the intersubband transition between the anti-crossing electronic subbands of the coupled quantum wells, which makes the structure a potential tuneable far infrared detector. Most of the experimental works have been modelled with a k.p theory using momentum matrix approach. The self-consistency incorporated in this model proves to be useful while dealing with semimetallic or nonintrinsic systems. These calculations offer invaluable clues to the semiconductor heterostructures investigated.
The synthesis of (+/-)- trichoviridin, WF-10129 and a biologically active analogue of antibiotic A-32390A

This thesis is divided into two parts:
Part 1
(i) The Synthesis of a Biologically Active Analogue of Antibiotic A-32390A
Methodology for the preparation of vinyl formamides from thiooximes has been developed for use with α-carboxy systems and successfully applied to the synthesis of (2S, 3S)-2,3-di-[hydroxybutane]-1,4-di-[2-isocyano-3-methyl-but-2-enoate], a vinyl isonitrile that is a biologically active analogue of the natural product, antibiotic A-32390A. In addition trifluoromethane sulfonic anhydride has been shown to be an effective reagent for the dehydration of vinyl formamides to vinyl isonitriles in these systems.
(ii) The Synthesis of (±)-Isonitrin C (Trichoviridin)
Further application of the methodology for the synthesis of vinyl formamides from thiooximes allowed for the effective preparation of 1α-(1'-t-butyldimethylsilyloxyethyl)-2β, 3β-epoxy-4-en-4-isocyano-cyclopentan-1β-ol, a key intermediate in the syntheses of the naturally occurring vinyl isonitriles, (±)-isonitrin A and (±)-isonitrin B. New methodology was developed for the synthesis of the epoxy-isonitrile functionality of (±)-isonitrin C (trichoviridin). Masking of the isonitrile functionality of 1α-(1'-t-butyldimethylsilyloxyethyl)- 2β, 3βp-epoxy-4-en-4-isocyano-cyclopentan-1β-ol by formation of the corresponding dibromoimine was followed by epoxidation of the C-C double bond with methyl (trifluoromethyl)dioxirane and removal of the bromine groups to regenerate the isonitrile moiety. Deprotection afforded (±)-isonitrin C (trichoviridin).
(iii) Mechanism of the Thiooxime Rearrangement
Some insight into the mechanism of the thiooxime rearrangement was obtained by 13C n.m.r. experiments and elucidation of the reaction by-products.
Part 2
A flexible route to optically pure γ-keto-α-amino acids using carbon based nucleophilic ring opening of activated monocyclic β-lactams has been established. Nucleophiles examined include lithiated sulfones, Lipshutz higher order organocuprates and lithiated phosphonates. This methodology has been applied to a high yielding synthesis of the naturally occurring potent ACE inhibitor WF-10129. The stereochemistry of WF-10129 was established, by synthesis of all possible diastereomers, to be S at all stereocentres.

Advisor: Baldwin, J
Learning between university and the world of work

Internships are an increasingly popular activity for university students wishing to learn about the world of work, and the term can encompass many types of opportunities for learning about industries, occupations, or simply the experience of a professional workplace.
The present study examines students following full-time degree courses across a range of subjects, in internships that are not integrated into course requirements. Internships of this kind are often located within the ‘employability agenda’ for higher education, developing students’ transferable skills to enable them to make smooth transitions to knowledge work outside the university. University careers advisors therefore encourage these internships as a form of experiential learning, and the notion of student employability is implicitly accepted by policymakers and universities.
Yet, little is known about how or what students learn in internships. This study, which took place over three summers, examines how six students from one university made sense of their ten-week summer internships in an investment bank. The students were interviewed prior to their internships, three times during the banking internship, and again on return to the university.
Using conceptual tools from sociocultural theory, the study starts from an understanding of movement between university and workplace as a matter of transition, rather than transfer and application, of knowledge and skills from university to the workplace. Adopting the idea of the ‘figured world’ (Holland et al., 1998) permits examination of how the students engaged with the cultural world of the workplace setting, interpreting and engaging with the practices there, and experiencing identity struggles that were of significance to them. The findings reveal the lack of support for the students’ engagement both before and during their placements, and have implications for the careers advising given to students undertaking internships.
The study therefore concludes with a presentation of the principles that underpin student experience of internships. Universities can assist this by providing more resources for guidance to students undertaking internships, by assisting them with developing an awareness of the motives that are inherent in the workplace, as well as their own motives and those of employers providing internships.

Keywords: transition
internship
university
Advisor: Edwards, A
Hayward, G
Volcanic processes during eruption and unrest: combining satellite and ground-based monitoring at Galeras and Santorini volcanoes

This dissertation explores the combination of Interferometric Synthetic Aperture Radar (InSAR) results with field data to provide additional constraints on the processes controlling deformation signals observed at Galeras volcano (Colombia) and Santorini volcano (Greece).
InSAR measurements during 2007-2008 at Galeras reveal a subsidence signal on its northeast flank. I model InSAR and gravity data to determine the best-fit parameters for the subsidence source and suggest this signal was caused by deflation of the magma chamber associated with the January 2008 eruption.
In January 2011, Santorini volcano entered a period of unrest characterised by earthquake swarms and caldera-wide uplift. I analyse satellite data over a period incorporating both the preceding phase of quiescence (1993-2010) and the phase of unrest (2011-2012). A subsidence signal is confirmed on the intra-caldera island of Nea Kameni during 1993-2010. I investigate several possible scenarios for its source, with my preferred explanation being a combination of cooling and contraction of historic lava flows, and loading from these flows inducing relaxation of the substrate. I also use a joint InSAR/GPS inversion technique to model the caldera-wide uplift observed during 2011-2012. I determine the optimal parameters for the deformation source and the temporal variation in volume change within the shallow magma chamber. The renewed activity offered an opportunity to observe how soil-gas emissions would respond to an influx of magma to a shallow reservoir. I employ a new approach (222Rn-δ13C systematics) to identify and quantify the source of diffuse degassing at Santorini during the period of unrest.
Finally, I present a new high-resolution merged LiDAR-Bathymetry grid, enabling detailed mapping of both onshore and offshore historic lava flows emplaced in the centre of Santorini caldera. Updated lava volumes provide new extrusion rate estimates and a means of estimating both the size and duration of future dome-building eruptions at Santorini.

Keywords: InSAR
Santorini
volcanology
Colombia
Advisor: Mather, T
Biggs, J
Pyle, DM
Forward genetic and cellular studies of immune regulation: the roles of Carma1, Interleukin-10 and Gimap5

The differentiation and functional specialisation of CD4+ T cells into distinct subsets allows inflammatory responses to be targeted to diverse types of insults. One subset of CD4+ T cells, Foxp3+ regulatory T (Treg) cells, acts to restrain excessive effector T cell responses and can develop in either the thymus or peripheral tissues. Here, a mouse with a germline point mutation in Carma1, an essential component of the signalling cascade linking the T cell receptor to NF-κB activation, is described. These mice were used to demonstrate a cell-intrinsic requirement for Carma1 in the development of thymic Treg cells that could be bypassed in peripheral CD4+ T cells. Interestingly, Carma1-deficient Treg cells accumulated both at the site of persistent viral infection and in the intestine of healthy mice, which harbours a high load of resident bacteria, suggesting that chronic inflammation can drive peripheral Treg cell induction or accumulation. Subsequent work showed that Treg cells in colon of healthy wild-type mice are unique in that they constitutively produce the immunosuppressive cytokine interleukin 10 (IL-10), whereas in the small intestine both Foxp3+ Treg cells and Foxp3- CD4+ T cells that resemble Tr1 cells produce IL-10. Production of IL-10 from both T cell subsets required the presence of intestinal bacteria, because IL-10 expression was abrogated by broad-spectrum antibiotic treatment. Additionally, IL-10 expression was enhanced in the colon and caecum upon colonization with Helicobacter hepaticus, a pathogen that can break tolerance of intestinal bacteria in Il10-/- mice. Finally, the characterisation of a mouse homozygous for a germline point mutation in Gimap5 demonstrated that this gene was required for the survival of T, B and NK lymphocytes. Additionally, these mice exhibited spontaneous hepatic extramedullary haematopoiesis, with an abundance of Lin-Sca-1+Thy-1high innate lymphoid cells in the liver, and became colitic when infected by H. hepaticus. Adoptively transferred lymphocytes prevented disease in these mice, suggesting that regulatory lymphocytes need Gimap5 to survive and function. Collectively, these studies identify novel genetic and microbial factors involved in maintaining intestinal homeostasis.

Keywords: inflammatory bowel disease
mutagenesis
cytokines
Carma1
T cells
immune regulation
Gimap5
Interleukin 10
Advisor: Powrie, F
Beutler, B
Free and linear representations of outer automorphism groups of free groups

For various values of n and m we investigate homomorphisms from Out(F_n) to Out(F_m) and from Out(F_n) to GL_m(K), i.e. the free and linear representations of Out(F_n) respectively.
By means of a series of arguments revolving around the representation theory of finite symmetric subgroups of Out(F_n) we prove that each homomorphism from Out(F_n) to GL_m(K) factors through the natural map p_n from Out(F_n) to GL(H_1(F_n,Z)) = GL_n(Z) whenever n=3, m < 7 and char(K) is not an element of {2,3}, and whenever n>5, m< n(n+1)/2 and char(K) is not an element of {2,3,...,n+1}. We also construct a new infinite family of linear representations of Out(F_n) (where n > 2), which do not factor through p_n. When n is odd these have the smallest dimension among all known representations of Out(F_n) with this property.
Using the above results we establish that the image of every homomorphism from Out(F_n) to Out(F_m) is finite whenever n=3 and n < m < 6, and of cardinality at most 2 whenever n > 5 and n < m < n(n-1)/2. We further show that the image is finite when n(n-1)/2 -1 < m < n(n+1)/2.
We also consider the structure of normal finite index subgroups of Out(F_n). If N is such then we prove that if the derived subgroup of the intersection of N with the Torelli subgroup T_n < Out(F_n) contains some term of the lower central series of T_n then the abelianisation of N is finite.

Keywords: representations
outer automorphisms of free groups
Advisor: Bridson, MR
Utility Maximisation: Non-concave utility and non linear expectation

Since the birth of mathematical nance, portfolio selection has been one of the topics which have attracted a lot of interest, with models formulated in discrete and continuous time and developed in complete and incomplete markets. In conventional or neoclassical finance, many models are based off the assumption that agents make decisions by maximising their expected utility. Deviations between models and market observations have generated a recent field of study, behavioural finance, which incorporates psychology, sociology and finance together to resolve observed phenomenon like bubbles which conventional finance cannot explain. In this thesis, we will be restricting ourselves to the complete continuous market and look at a new formulation of expected utility maximisation with behavioural finance elements incorporated into it, namely S-shaped utilities and probability distortions. We consider the three general cases of expected utility maximisation: utility from terminal wealth, utility from consumption and utility from terminal wealth and consumption. We shall review the neoclassical problems and then explore the cases with behavioural elements installed. Key Words: Portfolio Selection, continuous time, martingale approach, Sshaped function, probability distortion, cumulative prospect theory