VictorJuiz/thesis huggingface dataset:
Mechanical behaviour of irradiated tungsten for fusion power

Tungsten will be a key material for the plasma-facing components in future fusion devices. Its mechanical performance under neutron irradiation will strongly influence the lifetime of these devices. Pure tungsten has been subjected to a variety of irradiating species - tungsten ions, helium ions and fission neutrons - between 500°C and 900°C and the change in mechanical properties measured by micro-mechanical testing methods.
Pure tungsten has been ion-irradiated using self-ions and helium ions at 500°C and 800°C. Nanoindentation has been performed on all specimens, and the 800°C specimens have been tested at temperatures up to 750°C using high-temperature nanoindentation. The irradiation temperature has no effect on the hardening of tungsten. Hardening from self-ion irradiation has not saturated by 4.5 dpa with an increase in hardness of 3.3 GPa. The hardening from helium implantation is only 0.73 GPa, and a comparison with literature shows that this hardening only depends on the concentration of the injected helium. The difference is likely due to the much smaller defect size of helium-vacancy clusters when compared to dislocation loops. High-temperature nanoindentation shows that helium-implanted tungsten softens rapidly, with the hardening from the radiation damage becoming negligible above 450°C. Self-ion implanted tungsten does not soften by 650°C, again likely due to the size difference of the defects.
Micro-mechanical tests - namely micro-cantilever bending - have been used to investigate the plastic and fracture characteristics of tungsten before and after irradiation. Plastic behaviour is dominated by size effects due to the 3 μm depth of the implanted layers, which makes nanoindentation a better method for investigating radiation damaged layers. In fracture testing, fracture is rarely seen. Using the yield stress to calculate fracture toughness, the hardening from irradiation damage results in an increase in fracture toughness from 2.2 MPa√m to 6.0 MPa√m. The work of deformation at 1% is also increased after irradiation from 7.2 x 10-11 Nm to 2.8 x 10-10 Nm, implying that the implanted damage is not leading to an increase in embrittlement by reducing K1c.
Neutron irradiated tungsten also shows an increase in fracture toughness after irradiation from 6.5 MPa√m to 14.5 MPa√m. However, the BDTT increases by &Tilde; 100°C in poly-crystal tungsten and &Tilde; 500°C in single-crystal tungsten. The difference in BDTT does not exist in the unimplanted material. The change after irradiation is likely due to the fine (˜ 3 μm) grain size and 900°C irradiation temperature causing a significant amount of the displacement damage to be absorbed at the grain boundaries. The hardness of neutron irradiated and ion irradiated tungsten is very close: 10.4 GPa and 11.2 GPa respectively, demonstrating the ions are likely well-representing the neutron damage in pure tungsten.

Keywords: Nanoindentation
Tungsten
Fusion
Radiation Damage
Advisor: Roberts, S
Armstrong, D
The politics of culture in the world of René of Anjou

This thesis explores the way in which René, French prince and exiled king of Naples (1409-80), sought, by means of his transnational network of agents and allies, to assert his Italian political agenda chiefly through a programme of cultural politics. It is a case study for a ‘diplomatic’ approach to culture, and provides a new take on mid-fifteenth-century Italian politics as well.
René of Anjou was defeated in a war for Naples in 1442 by Alfonso V of Aragon, but he maintained his Italian connections in the hopes of a return to the throne. His Italian network was based on the once-powerful Guelph faction, and then also on his chivalric Ordre du Croissant, which counted amongst its members the mercenary captain and usurping duke of Milan, Francesco Sforza. A programme of cultural politics, sometimes involving the exchange of gifts, other times simply involving politically-affective language, was part of keeping this network together. It was at the heart of the relationship between King René and Jacopo Antonio Marcello, a Venetian patrician and Croissant knight who brokered René’s connection to a number of major Italian cultural figures: Giovanni Bellini, Guarino of Verona, Andrea Mantegna, and Janus Pannonius, among others. The works they produced were crucial to the development and aggrandizement of the network, which was the foundation of a power bloc intended to return René to power in Naples. René tried to exploit this network in the Lombard wars of the early 1450s, but the Italian League that emerged in 1454 actually worked against René and his Guelph allies, particularly those in Florence who posed a threat to the Medici regime. After René’s ultimate military failure in the 1458-64 Neapolitan war of succession, his network evolved into a faction opposed to the Italian League and the state system it sustained.

Advisor: Watts, J
Interlocked host structures for anion recognition and metal nanoparticles for catalysis and sensing applications

This thesis describes the synthesis and anion recognition properties of a variety of interlocked host receptors and the application of metal nanoparticles in the areas of catalysis and sensing.
Chapter One introduces the field of anion supramolecular chemistry, with particular emphasis on areas relevant to the research discussed in later chapters. Following this, the synthesis and applications of metal nanoparticles are outlined.
Chapter Two details the synthesis of a range of halo-triazolium based rotaxanes and explores the effects of altering both the halogen bond donor atom and degree of preorganisation on the anion recognition properties of the interlocked host system. A halogen bond containing catenane is also prepared and its anion binding properties investigated.
Chapter Three initially reports the anion-templated synthesis of a series of neutral pyridine N-oxide axle containing rotaxanes before their ability to recognise anions in aqueous solvent mixtures is studied. Attempts to enhance anion binding through the incorporation of a positive charge into the macrocyclic component of the rotaxane structure are also explored.
Chapter Four outlines the preparation of β-cyclodextrin functionalised metal nanoparticles and investigations of their catalytic and sensing properties.
Chapter Five describes in detail the synthetic and analytical procedures discussed in chapters two to four.
Chapter Six summarises the conclusions of this thesis.

Keywords: Supramolecular Chemistry
Rotaxanes
Catalysis
Anion Recognition
Nanoparticles
Advisor: Beer, P
Cookson, J
A novel fluorinated probe for medical imaging

Medical imaging is an important area of scientific research with the principle aim of accurately diagnosing diseases to guide more effective treatment. Magnetic resonance imaging (MRI) provides advantageous high spatial resolution and deep tissue visualization. However, 1H MRI can suffer from low signal-to-noise ratios due to strong background signals from abundant, endogenous molecules such as water and fat. 19F MRI overcomes this drawback by directly detecting administered 19F-labelled agents without any background signal.
This thesis reports the design and development of a new fluorinated agent for medical imaging. The bacteriophage Qβ, which comprises 180 copies of its coat protein, was used as the scaffold for the imaging agent. The fluorinated amino acid trifluoromethionine (TFM) was incorporated into the Qβ coat protein by the sense codon reassignment method using auxotrophic E. coli. This marks the first example of introducing fluorine into a virus by genetic modification. Reports of previous attempts to incorporate TFM into proteins have shown low to good incorporation levels (the maximum being 82%). Here, extensive optimisation of the protein production conditions resulted in unprecedentedly high incorporation levels (96%). Analysis of the modified Qβ-F by agarose gel electrophoresis, dynamic light scattering and transmission electron microscopy showed the coat protein self-assembles into virus-like particles (VLPs), essentially indistinguishable from the wild-type Qβ VLPs.
The intact Qβ-F VLP gave no 19F NMR signal. This was rationalised in terms of the VLP’s high molecular weight and resulting fast transverse relaxation. Stimulating disassembly of the VLP by addition of dithiothreitol (DTT), sodium dodecyl sulphate (SDS), or a combination of the two resulted in the development of 19F NMR peaks. Multimers and monomers of the disassembled Qβ-F were distinguished by 19F NMR and 19F DOSY. This result was verified by measuring the 19F NMR of a prepared sample of alkylated Qβ-F monomer and comparing its chemical shift value with that of peaks from the 19F NMR of the disassembled Qβ-F VLP.
Finally, initial in vivo experiments were carried out in order to investigate the biodistribution of the Qβ-F particle. After injection of Qβ-F VLPs into rats, organs were dissected and homogenized. The Qβ-F particle was found to accumulate predominantly in the liver. 19F NMR of the liver after sucrose density gradient ultracentrifugation only showed a signal on incubation with DTT, demonstrating that the Qβ-F particle remained intact in vivo.

Keywords: Fluorinated protein
medical imaging
MRI
protein modification
Advisor: Davis, B
Schofield, C
Polarization in electron-proton scattering

This thesis is concerned with polarization effects in elastic electron-proton scattering. The principal results are summarized below.
A general polarization analysis of high-energy electron-proton scattering is first presented, and the problem of a 'complete set' of experiments, which allow a unique determination of the elastic scattering matrix at one energy and scattering angle, is discussed. A straightforward reconstruction procedure is shown to be inadequate when an expansion of the strength of interaction in powers of andalpha;, the fine structure constant, is reasonable: an alternative procedure for this case involves using both electron and positron scattering experiments. Although the experimental evidence for the one-photon-exchange approximation in electron-proton scattering is generally accepted to be very good, from a strictly logical point of view the analysis is incomplete and does not permit an unambiguous determination of the two-photon-exchange amplitudes. It is shown that measurement of various polarization tensors for both electron and positron scattering could eliminate the ambiguity.
Some interesting polarization experiments are then considered, in the one-photon-exchange approximation. A specific experiment is suggested to measure the electric form factor of the proton GE, and explicit expressions are derived for the proton depolarization tensor. In the time-like region, the form factors are not restricted to real values and a 'generalized' polarization-asymmetry relation for the two crossed-channel processes, PP andrarr; e+eandminus; and e+eandminus; andrarr; PP, may be derived. Violation of this relation would represent a violation of time-reversal-invariance and JCP-invariance.
The polarization of the recoil proton in elastic electron-proton scattering is strictly zero in the one-photon-exchange approximation: any non-zero polarization must, to lowest order in andalpha;, arise from interference of the one-photon-exchange amplitudes with two-photon-exchange amplitudes. The contribution to the polarization of the two-photon-exchange amplitude with an elastic intermediate state, is calculated for arbitrary form factors for the proton. Numerical results are displayed for two interesting parameterizations of the form factors. This elastic effect is expected to be a good approximation to the polarization up to energies where the production of inelastic states becomes important. A rigorous upper bound is derived for the contribution to the polarization, of all two-photon amplitudes involving multi-particle intermediate states: the bound involves measurable inelastic electron-proton cross sections. However, a rough numerical estimate shows the bound has very limited usefulness, since it leads to very large bounds at large momentum-transfers.
New approaches to understanding income differences and current account imbalances

This thesis employs two new approaches to explain some of the important debates in two key economic fields: labour market economics and macroeconomic studies related to current account imbalances.
Chapter 1, Chapter 2 and Chapter 3 begin a new strand of research by introducing the normal inverse Gaussian (NIG) distribution to describe unobserved heterogeneity in the labour market. The NIG distribution can be represented as a normal variance-mean mixture with the inverse Gaussian (IG) distribution as the mixing distribution. A 0.01% subsample of the 1980 US Census, comprising all men between 18 and 65 who are in the labour force, as well as a comparable sample from Ghana, is used to show that the NIG distribution provides a better fit of the log earnings function than the normal distribution. The prediction of right skewness of the log earnings distribution arising from the log normal skill Roy selection model is rejected in favour of left skewness. The thesis then extends the model to describe the distribution of log earnings conditioned on education. The same two datasets (US males and Ghanaian males) are used for the empirical analysis. We find that, once the unobserved heterogeneity is accounted for, the return to education is almost flat for lower levels of education in Ghana, and then increases for education levels greater than ten years. One of the key differences between the two datasets is that skewness and unobserved heterogeneity is a function of education for Ghana but not for the US. The NIG framework is found to be a useful tool to model this heterogeneity.
Chapter 4 uses a model that allows for a rich structure of age effects similar to those predicted by the life cycle theories to argue that the demographic shifts are partly responsible for the sustained rise in the US current account deficit and the rapid increase in China's current account surplus in the last decade. However, demographics do not have an impact on the long run equilibrium or level of current accounts. Rather, they are important determinants of the short run adjustment of current accounts to their equilibrium levels. In the next twenty years, the demographic shifts are likely to push towards further current account positive adjustments in China and current account negative adjustments in the US. Developing the infrastructure, financial markets, policy tools and regulatory settings to be able to cope with the excess capital flow remains an urgent task.

Keywords: Current Account Imbalances
Labor Economics
Advisor: Nielsen, B
Teal, F
Energy transfer in biomimetic and biosensing molecular nanomaterials

This thesis is concerned with ultrafast photophysics and excitation energy transfer in biomimetic and biosensing molecular nanomaterials, which have been investigated using timeresolved photoluminescence spectroscopy.
Artificially-synthesised fully pi-conjugated nanorings with 6-24 units of porphyrins incorporated have demonstrated remarkable full delocalisation of the absorbing excited state across the entire ring on an ultrafast timescale. The largest ring of 24 porphyrin units with a diameter of ~10 nm is the largest man-made molecular nanoring at present. The constraint that the lowest electronic transition is forbidden due to their high molecular symmetries is released by static and dynamic distortions in the solution. These findings provide promising opportunities for using these man-made light-harvesting materials that match the efficiency of their natural counterparts in technological applications.
On the other hand, self-assembled organic fluorescent nanoparticles (NPs) formed of amphiphilic monomers with targeting ligands exhibit potential to be used in bio-sensing applications. Homotransfer and heterotransfer of excitation energy in nanoparticles have been investigated, where mannose covalently linked on Amp1-B monomers provide binding sites for Concanavalin A which is attached with energy acceptors. Increasing the molar ratios of Amp1-B-mannose and Amp3-B can increase the binding sites and forming directional energetic cascades towards the NP surface, respectively. However, the amount of these two monomers must be optimised in order to reach the highest donor-acceptor energy transfer rate in the system.

Keywords: light-harvesting
FRET
pi-conjugated materials
photophysics
Ultrafast spectroscopy
biosensing
Advisor: Herz, L
The impression in the essays and late novels of Henry James

This thesis examines the meanings and uses of the impression in the essays and late novels of Henry James. While James found fault with impressionism in French painting and literature, he repeatedly called the novel an ‘impression of life’, and used the term to figure important moments of perception and action for his protagonists. This thesis offers the first full-length study of the impression on its own terms, rather than through the lens of a wider artistic or philosophical movement, the most obvious example being impressionism. It locates James’s impression within an intertextual history comprising British empiricist philosophy (Locke and Hume), empiricist psychology (William James), British aestheticism (Pater and Wilde), and, looking forwards, twentieth-century theories of the performative (Austin, Derrida, de Man, Butler). It offers a series of close readings of James’s non-fictional and fictional treatments of the impression in his early criticism and travel writing (1872-88), his prefaces to the New York edition (1907-09), and the three novels of his major phase, The Ambassadors (1903), The Wings of the Dove (1902), and The Golden Bowl (1904). This exploration does not produce any unified definition of the impression in the work of James. It finds, rather, that the impression crystallizes one of James’s main themes, the struggle between art and life, a consequence of the competing empiricist and aesthetic tendencies that the thesis distinguishes within accounts of the impression available to James. The thesis goes on to show that impressions in James may be made as well as received, and so introduces a further distinction, between ‘performative’ and ‘cognitive’ impressions. It argues that what James does with these competing impressions – empiricist and aesthetic, cognitive and performative – is to make them the narrative focus of his late novels and their drama of consciousness.

Keywords: art and literature
philosophy and literature
impressionism
Henry James
1843-1916 - criticism and interpretation
empiricism and literature
aestheticism
psychology and literature
English fiction - twentieth century
Advisor: Bush, R
Johnson, J
Colombian police policy: police and urban policing, 1991-2006

The purpose of this research is to analyze Colombian police policy with particular reference to the police and urban policing after the promulgation of the Constitution of 1991. This study examines how the Constitution of 1991 has impacted on the configuration, professionalization and institutionalization of the Colombian police. This dissertation concludes that the new Constitution of 1991 was crucial in transforming an insignificant organization into a noteworthy public institution with its own corporate aims and ethos and a certain autonomy regarding the government, parties, ministries and the military. This research is divided into three main parts. The first one will focus on the police as a structure emphasizing the process of formation, development and institutionalization. It dissects the police structure into five aspects: historical configuration, structural organization, personnel, expenditure and controls. This part shows that the current importance of the police in the Colombian institutional landscape in terms of international aid, personnel and budget increase and public exposure has no precedents prior to 1991.The second part will be devoted to the study of the organizational life of the police force stressing the role played by high-ranking officers in improving the image of the police and, more importantly, in creating a vigorous institution difficult to control from outside, but at the same time, not easy to manage internally as a consequence of the distinction existing between high-ranking and low-ranking officers. The final part of this work examines urban and community policing in large urban areas taking the case of Bogotá. It focuses on the role played by the police in its implementation, successes and failures, concluding that the reluctance of the police to adopt these programmes of policing has limited their productive effects on the actual job and indeed the whole organization.

Keywords: Colombia
police
policing
new-institutionalism
government
Advisor: Deas, M
Establishing evidence-based training of cognitive behavioural therapy treatments: empirical and theoretical guidance for dissemination

The need to provide effective Cognitive Behavioural Therapy (CBT) treatments in routine clinical practice necessitates effective methods of CBT training, which are scalable and can be disseminated in populations without ready access to specialist trainers or large scale funding. This thesis seeks to add theoretical and empirical guidance to the development of evidence-based CBT training. The first chapter reviews the current literature on effective CBT training, and suggests theoretical and methodological guidance for future research on evidence-based training practices. Cohort studies (Chapters 2 – 4) examine data from former trainees for guidance on accurate CBT competence measurement and effective CBT training components. The fifth and sixth chapters report randomised-controlled trials examining the effects of internet-based training (IBT) on therapists’ competence and patient outcomes (Chapter 6). Findings from the literature review (Chapter 1) and Chapter 2 suggested the need for training effectiveness trials using treatment trial methodology, which includes ‘blind’ observer ratings of therapist behaviour as the measure of competence. Chapter 3 found that extensive training led to significant improvement in competence for trainees with a range of individual baseline characteristics. Since such extensive training is not accessible to the majority of practicing therapists, Chapter 4 examined which elements of extensive training were perceived by trainees as having the greatest positive effect on competence; thus providing empirical guidance in planning more scalable forms of training, such as IBT. Findings from the first four chapters provided guidance in planning the two randomised controlled trials outlined in Chapters 5 and 6, resulting in rigorous empirical data showing significant positive effects of IBT on therapists’ competence and on their patients’ clinical outcomes. Finally, the results of this thesis are related to the framework for developing evidence-based training, which was suggested in Chapter 1 and suggestions for future research are made.

Keywords: therapist competence
cognitive behavioural therapy
dissemination
training
Advisor: McManus, F
Zariski structures in noncommutative algebraic geometry and representation theory

A suitable subcategory of aﬃne Azumaya algebras is deﬁned and a functor from this category to the category of Zariski structures is constructed. The rudiments of a theory of presheaves of topological structures is developed and applied to construct examples of structures at a generic parameter. The category of equivariant algebras is deﬁned and a ﬁrst-order theory is associated to each object. For those theories satisfying a certain technical condition, uncountable categoricity and quantiﬁer elimination results are established. Models are shown to be Zariski structures and a functor from the category of equivariant algebras to Zariski structures is constructed. The two functors obtained in the thesis are shown to agree on a nontrivial class of algebras.

Keywords: 81R
18F
16G
03C
Advisor: Zilber, B