VictorJuiz/thesis huggingface dataset:
Velocity selective preparations in Magnetic Resonance Imaging

Arterial Spin Labeling (ASL) is a Magnetic Resonance Imaging (MRI) technique that is able to non-invasively quantify the rate of delivery of arterial blood to tissue, known as perfusion. In this thesis a method that uses Velocity Selective (VS) preparations to generate contrast between blood and tissue spins is investigated.
The systematic errors associated with performing a VSASL experiment on imperfect hardware is first investigated. It is shown through simulations and experiments that some VS preparations will underestimate perfusion due to static and transmit magnetic field errors, and that eddy currents caused by switching of magnetic gradients lead to an overestimation of perfusion with VSASL by up to a factor 2. A novel VS preparation, BIR-8, is presented which is shown to be the most robust to these imperfections.
The BIR-8 VSASL technique is then applied in brain tumours where it is found that significant VSASL signal can be detected in less than 5 minutes. However, in a comparison with a spatially selective ASL technique it is found that VSASL overestimates perfusion in these tumours, despite agreeing in Grey Matter.
The systematic errors due to physiology are then modelled, and it is shown that both diffusion and bulk motion will systematically bias the VSASL measurement. A diffusion insensitive VSASL technique, VS-TILT, is then developed and it is found that a significant proportion of the VSASL signal originates from diffusion effects. Theoretical models for the shape of the bolus in vascular networks are also derived, and it is shown that an isotropic network of laminar vessels produces the most efficient saturation, but saturation is also achieved with plug flow.
The diffusion insensitive VS preparation is then applied in an attempt to isolate the venous compartment in order to measure Oxygen Extraction Fraction. A kinetic model is derived in order to optimise the acquisition. However, it is found that accurate measurements of OEF would not be produced by this sequence in a clinically realistic time.

Keywords: MRI
Magnetic Resonance Imaging
Arterial Spin Labeling
Advisor: Jezzard, P
Field emission from porous silicon

Vacuum microelectronic (VME) devices are of interest for the development of flat-screen displays and microwave devices. In many cases, their operation depends on the field emission of electrons from micron-sized cathodes (semiconductor or metal), into a vacuum. Major challenges to be met before these devices can be fully exploited include obtaining - low operating voltages, high maximum emission currents, uniform emission characteristics, and long-term emission stability.
The research in this thesis concerns the production of silicon field emitters and the improvement of their emission properties by the process of anodisation. Anodisation was carried out for short times, in order to form a very thin layer of porous silicon (PS) at the surface of both p and p+-type silicon emitters. The aim in doing this was to form a high density of asperities over the surface of the emitters. It was the intention that these asperities, rather than the "macroscopic" apex of the emitter, would control emission. This was the first work of its kind to be carried out.
Transmission electron microscopy was used to characterise the morphology of p and p+-type silicon emitters before and after anodisation. Both the structure and arrangement of the surface fibrils, the thickness of the PS layers at the apex and nature of PS cross-sections were studied. The morphology was correlated to subsequent field emission measurements.
Field emission characteristics, before and after anodisation, were obtained using a scanning electron microscope adapted for field emission measurements, and a field emission microscope. Extensive measurements showed that, following anodisation, there was substantial improvement in emission behaviour. After anodisation, the following was found to be true:
i) The starting voltage was reduced by up to 50% (with p+
ii) Number of emitting tips per array was increased.
iii) Higher maximum currents (up to 3 times higher) were obtained before tips underwent destruction.
iv) The resistive effect of the PS layer at the apex was important in determining the maximum current obtained from a tip.
In addition, both field emission and field ion microscopy were used to identify the emission source following anodisation. It was shown that individual fibrils on the emission surface caused an increase in field enhancement over a flat plane, leading to emission at lower voltage.
Overall, porous silicon appears to be a very promising material for field emission displays.
Authenticity and the commodity: physical music media and the independent music marketplace

This thesis examines the circulation of physical music media (78rpm records, LPs, CDs, tape) in the independent music marketplace. It is based on six months of ethnographic fieldwork in Austin, Texas, amongst the producers of goods for the independent marketplace, independent music stores and consumers of these goods and services. Against prevailing constructivist interpretations, I will argue for the value of authenticity as an analytical anthropological concept because it unites what my research participants value about materiality, technology, and marketplace relationships. In the independent marketplace for physical music media, authenticity is a multi-local, multi-vocal phenomenon. A nexus of economic rationales, design, reproduction-technologies, histories and personal conduct interact in an ongoing process that authenticates music commodities and their marketplace. This means that particular commodities are sought out over others on account of the multi-local authenticities they anchor. The thesis firstly demonstrates how the independent music scene safeguards claims to authentic identities by constructing an opposition to the mainstream, drawing on discourses of ethical production and consumption, sound technologies, spaces of consumption and cultural production. Secondly, I will uncover how physical music media and sound-reproduction technologies are assessed as effective providers of authentic musical reproductions according to their historical contingencies and performative material capacities. Thirdly, I develop the notion of the scene (Shank 1994) from its previously genre-fixed perspective to encompass multiple musical styles operating within a common social network of producers, retailers and collectors. The pluralistic scene I describe utilises multiple musical genres and nuanced notions of materiality and authenticity to establish their complex hierarchy of sonic and technological experiences.

Keywords: Texas
culture industries
ethnography
sound recording
material culture
music industry
sound technology
Austin
consumption
ethnomusicology
anthropology
collecting
popular music
materiality
Advisor: Daniels, I
Economic rationality and political viability, prerequisites in economic reform?

To address the research questions - How has the Chinese government been able to produce a successful reform process and what logic has been behind it? - I develop a politico-economic framework that is largely based on a public choice model by Frey and Eichenberger (1992) and a politico-economic research methodology by Bates and Kreuger (1993). Its basic assumption is that all individuals, including bureaucrats and autocrats, maximise their own power and money subject to constraints. Secondly, it assumes that, when a new leadership rises to power, it will try to start an economic reform process in order to secure its power position. Per reform period, economic reform plans are analysed on their intended effect, implementation and actual results in pure economic terms as well as in political terms (leadership's power position). The framework hypothesises that during a reform process a government will perform a constant balancing act between the political viability with the economic rationality of each individual reform measure.
This hypothesis is testedJand the Chinese reform period 1978-1995. The constraints Deng Xiaoping's leadership faces are the Communist Party's rule, a very strong bureaucracy, management of state enterprises and military, the command economy with an agricultural commune system and a revenue dependency on state owned enterprises. The hypothesis largely holds for China: agricultural reforms start with liberalisation to be later on largely retracted; real state owned enterprise reforms are never implemented; rural industrial reforms boom after tax revenues could be withheld at local level; the military's civilian industries is thriving. Unwanted results are quickly changed or retracted in the following period. Also identified is that despite these efforts, unintended interlinkage effects between the different reform measures become increasingly important and difficult to assess, resulting in a great loss of power for the leadership.
Contest and community: wonder-working in Christian popular literature from the second to the fifth centuries CE

In this thesis, I hope to demonstrate that what I call the magic contest tradition, that is the episodes of competitive wonder-working that appear in a wide variety of apocryphal and non-canonical Christian texts, made an important contribution to the development of Christian thought during the second to the fifth centuries CE. This contribution was to articulate ‘the way’ to be a Christian in a world which was not isolated from the secular, and not insulated from the reality of the Roman empire. First, I demonstrate that a tradition of texts which feature magic contests exists within the broader scope of non-canonical Christian literature (looking at this literature across communities, regions and time periods). Second, I identify what the major features of the traditions are, e.g. what form the narratives take, what the form for a magic contest is, and what the principles used to build the magic contests are, and how these principles feature in the texts. The principles I identify are power, authority, ritual, and conversion, as well as their use as historical exempla. Third, I discuss what the texts did in the context of the time period, and for the communities that produced and read them: in other words, how did the this tradition work? I show that they served multiple purposes: as tests of faith, religious truth and ways to proclaim such; as constructors and markers of group identity (and the perilous task of identifying the insiders and those who should be outsiders); as calls to unity within the overarching diversity of the times and places, and a unified front for the ‘battle’ against evil. I suggest that the texts present a model for how one could decide what the ‘true faith’ was and how one could practice it in the turbulent environment that early Christians faced both before and after Constantine.

Keywords: apocrypha
Judaism in the Roman world
Acts of Peter
early Christianity
Acts of Silvester
Magic
ritual
Advisor: Morgan, T
Custom and conflict in a Wealden village

This thesis aims to determine the relationship between demographic/ socio-economic and cultural change in an early modern English village. The village of Pluckley in the Weald of Kent was chosen for the richness of surviving documentation both at a regional and a parochial level. This has enabled Pluckley's experience over the 150-year period after 1550 to be located in the context of regional developments, thus permitting a fuller appreciation of the significance of such micro-history to the national life of the period.
Pluckley's geographical location on the boundary between scarpland and wealden Kent resulted in a relative shortage of common, waste and forest suitable for encroachment or squatting. This spared the village the high levels of immigration found in many woodland-pasture communities, but considerable indigenous population growth during the 1590s-1620s needed to be accomodated. This required the sub-division of many existing holdings; a process made possible by the expansion of textile manufacture in the region. The result was two-fold: a consolidation in the position of small husbandmen and craftsmen in the village at the expense of more substantial landholders; and an increase in the numerical importance of Pluckley's poorest strata -labourers, cottagers, poor craftsmen and widows.
Two responses to the interlocking demographic and economic crisis of the late sixteenth and early seventeenth centuries can be observed. One was the emigration of perhaps ten per cent of Pluckley's households in the three decades following the industrial crisis of 1630-1. The other was revealed in the apparent resentment of some village officeholders -many of them middling farmers not immune to the financial pressures of the period- to the increased burden posed by the expanding population of poor in the village. This resentment found expression in an attempt to tighten standards of sexual and marital conduct during the period 1590-1640.
There is no evidence, however/ that sustained reforming activity in the village extended beyond sexual regulation to other 'disorders' associated by contemporaries with popular culture. Relatively low levels of poverty in the village (compared with elsewhere in mid-Kent) may have hindered the emergence of a powerful Puritan lobby bent on such reforms; though fissures within Pluckley's ruling elite as well as demographic and economic developments may have played their part in the continuing weakness of the 'godly' cause.
Micro-mechanics of irradiated Fe-Cr alloys for fusion reactors

In the absence of a fusion neutron source, research on the structural integrity of materials in the fusion environment relies on current fission data and simulation methods. Through investigation of the Fe-Cr system, this detailed study explores the challenges and limitations in the use of currently available radiation sources for fusion materials research.
An investigation of ion-irradiated Fe12%Cr using nanoindentation with a cube corner, Berkovich and spherical tip, and micro-cantilever testing with two different geometries, highlighted that the measurement of irradiation hardening was largely dependent on the type of test used. Selected methods were used for the comparison of Fe6%Cr irradiated by ions and neutrons to a dose of 1.7dpa at a temperature of 288°C. Micro-cantilever tests of the Fe6%Cr alloy with beam depths of 400 to 7000nm, identified that size effects may significantly obscure irradiation hardening and that these effects are dependent on radiation conditions. Irradiation hardening in the neutron-irradiated alloy was approximately double that of the ion-irradiated alloy and exhibited increased work hardening. Similar differences in hardening were observed in an Fe5%Cr alloy after ion-irradiation to a dose of 0.6dpa at 400°C and doses rates of 6 x 10-4dpa/s and 3 x 10-5dpa/s. Identified by APT, it was shown that increased irradiation hardening was likely to be caused by the enhanced segregation of Cr observed in the alloy irradiated with the lower dose rate.
These observations have significant implications for future fusion materials research in terms of the simulation of fusion relevant radiation conditions and micro-mechanical testing.

Keywords: neutron
dislocations
size effects
radiation
micro-mechanical testing
dose rate
radiation defects
radiation damage
displacement damage
plasticity
irradiation
ion implantation
fe-cr alloys
Advisor: Roberts, S
Dudarev, S
The accountability of UN post-conflict administrations for violations of international humanitarian law and human rights law

The thesis explores the extent to which the UN post-conflict administrations are accountable towards the populations of the territories they administer. The post-conflict administrations temporarily assume legislative and administrative powers to support the peace processes, to help to resolve the sovereignty issues or to establish administrative structures that might be non-existent in these territories. The thesis argues that, while the exercise of these extensive powers entails the accountability of the UN, in practice this accountability is not effectively engaged.
As opposed to other forms of accountability, the focus is on the international legal responsibility of the UN as the prominent and most meaningful form of accountability, in the accountability relationship between the administrator and the administered, which gives the populations of the administered territories the opportunity to challenge the acts of international administrations and seek redress.
In exploring the legal responsibility of the UN and in line with Article 4 of the ILC Draft Articles on the Responsibility of International Organizations, which states only an act of an international organization that constitutes a breach of an international obligation entails its responsibility, this thesis initially explores the extent of international obligations arising from, and the extent of applicability of, three bodies of law. First, the thesis discusses the applicability of international humanitarian law, the fundamental principles of which have traditionally been part of UN peace operations practice. Next, it considers the applicability of the law of occupation, which shares stark factual similarities with the UN post-conflict administrations. Finally, the applicability of international human rights law, which is consistently part of the applicable law in post-conflict territories, and the protection and promotion of which is consistently included in the mandates of post-conflict administrations is examined. The thesis argues that the simultaneous application these bodies of law would help to create a legal framework to engage the accountability of UN post-conflict administrations and this legal framework should be complemented by effective accountability mechanisms.

Keywords: international territorial administrations
immunities of the UN
occupation of territories
legal responsibility
human rights
armed conflict
accountability
Advisor: Goodwin-Gill, G
Towards a unified methodology for the design and development of distributed control system software

A unified approach to the design and development of distributed control software is presented. This method is the result of a 'tight' integration between a formal method for concurrent systems (CSP) and a structured method for distributed control system (DARTS). The work presented in this thesis does not seek to extend the semantic model of CSP nor to design a specific control algorithm, rather, efforts are made to apply the existing specification and verification techniques to enhance the formality of the well established and case-proven structured counterparts that benefits are captured from both methods.
As a methodology is the central aim, the suggested approach is a first step towards a complete unified software development environment, which engineers can follow from organising design ideas to system implementation with proven correctness. The thesis develops a set of parameterised CSP predicates for expressing concurrency and communication together with a corresponding set of generic processes to reflect these specified behaviours. These generic processes are formal building blocks for generating system implementations at different levels of abstraction. Utilisation of DARTS criteria and the parameterised CSP objects frame the refinement strategies. Also, mappings of generic processes to pictorial representations are suggested which enable easy assimilation of the evolving designs.
Applicability of the approach is demonstrated through a high level software design of a highperformance robot control system where its suitability is shown via requirement specifications, properties verification and implementation of salient behaviours using generic building blocks. Although verification often means rigorous mathematical reasoning, the thesis presents a proof assistant the Causality Diagram Evaluation Tool to automate the manipulation of CSP processes according to the defined algebraic laws. It is shown to be of value in reasoning with designs and implementations of the robot system. It is found that the analysis facility and the graphical interpretation of communication provided by the tool allow effective analysis and manipulation of early designs.
The results derived from specifying essential design details, from transforming highly abstracted implementation models, and from investigation of system behaviours through formal reasoning and simulation conclude that formal methods, in particular CSP, has a niche value in enhancing software reliability at the sub-system level as well as providing a better underpinning to the structured method DARTS. The end product is a method to generate a correct and unambiguous document of the system concerned that is amenable to a direct implementation.

Advisor: Daniel, R
Economic geography of the ancient Greek countryside

PART I: APPROACHES TO THE STUDY OF THE ANCIENT GREEK COUNTRYSIDE
CHAPTER 1: THE ANCIENT GREEK COUNTRYSIDE IN CLASSICAL SCHOLARSHIP
The Introduction locates the present study within the wider historiography of research into the ancient Greek countryside, assessing the contribution of geographical, archaeological and anthropological studies to the history of the ancient countryside, and analysing the methods which have tended to place the subject on the margins of traditional, text-based studies of the ancient world.
CHAPTER 2: THE CONTEXT OF THE CASE STUDY
Ch. 2 justifies the choice of the island of Siphnos as a case study to reassess the archaeology of the ancient Greek countryside in the light of the Ch. 1. The regional context, and the physical environment of this particular polis, are briefly described.
CHAPTER 3: THE ARCHAEOLOGICAL RECORD OF RURAL SITES
More than fifty rural sites exhibiting monumental masonry construction (towers and associated structures) have been recorded throughout the chora of Late Classical-Hellenistic Siphnos. Problems in identifying and dating occupation at rural sites are discussed within the context of the island's topography and long-term settlement history. Historical, epigraphic, ethnographic and archaeological evidence is considered with regard to the interpretation of monumental rural sites. The sites are then re-examined with regard to their architectural construction (Ch.4), their location and distribution (Ch.5), local land use (Ch.6), and the regional context of the countryside (Ch.7), in order to examine the economic geography of the polis.
PART II: MONUMENTAL RURAL SITES IN THE CHORA OF ANCIENT SIPHNOS
CHAPTER 4: SOCIAL ARCHAEOLOGY OF THE COUNTRYSIDE - ARCHITECTURE OF RURAL SITES
The rural sites are analysed according to their architectural plan, construction, orientation, and the presence of adjoining and adjacent structures, walls, courtyards, buildings and water collection devices.
CHAPTER 5: SOCIAL ARCHAEOLOGY OF THE COUNTRYSIDE - LOCATION AND DISTRIBUTION OF RURAL SITES
The location of rural sites is examined according to aspect, elevation, coastal distance, intervisibility and nearest neighbour analysis in order to examine hypotheses concerning their functions. It is argued that the majority of rural sites on Siphnos fulfilled an agrarian, rather than strategic function.
CHAPTER 6: SOCIAL ARCHAEOLOGY OF THE COUNTRYSIDE - LAND USE AT RURAL SITES
Many monumental rural buildings were built on steep sloped uplands (eschatiai). Strategies of land use (including extractive activities, agriculture, animal husbandry) are considered in relation to the architecture and location of rural site complexes.
CHAPTER 7; CONCLUSION - RURAL SITES AND THE POLIS
The Conclusion evaluates the findings of the case study according to patterns of rural building and land use in the ancient Greek countryside and discusses future opportunities for research in the subject.
Volume II contains Appendices and Plates relevant to the case study in Volume I.

Advisor: Purcell, N
Coulton, J
Osborne, R