VictorJuiz/thesis huggingface dataset:
Dispersion in oscillatory flows

The enhanced axial mixing which is caused by dispersion in oscillatory flows in some mass transfer devices may limit the reactor performance. This effect has provided the motivation for the present study in which oscillatory flow dispersion in a flat channel of large aspect ratio is investigated. The rate of spreading of a uniform slug of some passive tracer has been predicted using numerical and analytical techniques and the results have been verified experimentally.
The numerical approach has used a finite difference time-marching method to obtain predictions for the channel concentrations. From the results, the dispersion coefficient (D) has been evaluated for Strouhal numbers of O.O1→0.2 and for mean Reynolds numbers of O.4→2OO at Schmidt numbers (Sc) O(1O³) . It has been concluded that under these conditions D varies as stroke squared. Unless the flow is not quasi-steady (i.e. if pulsatile Reynolds number α²<O(l)) D is only a weak function of frequency. These predictions for the dispersion coefficient have been in excellent agreement with those of Watson (256). It has also been concluded from the numerical study that the phase of the velocity sinusoid at the instant of injection has a critical effect upon the form of the concentration evolution.
An approximate analytical technique has been developed in which weighted mean cross-channel concentrations are defined. The wall concentration is expressed approximately using a Fourier series. This procedure leads to ordinary differential equations for the axial moments. When the axial variance of mean concentration and the dispersion coefficient were computed in this way for quasi-steady flows good agreement was obtained with the numerical work.
Simple opto-electronic gauges have been developed to measure mean cross-channel concentrations. The sensors have been used to obtain experimental data for the dispersion coefficient of a furrowed channel mass transfer device using slug stimulus techniques. Experimental investigations of dispersion in oscillatory flows in a flat channel using these gauges has produced values for D which are in agreement with the theoretical predictions for quasi-steady flows.

Advisor: Bellhouse, B
Sobey, I
The Vir Tricultus: an investigation of the classical, Jewish and Christian influences on Jerome's translation of the Psalter Iuxta Hebraeos

This thesis investigates the influences on Jerome's translation of the Psalter from the Hebrew (IH Psalter) that came from the three major socio-religious spheres with which Jerome was acquainted. It argues that the results offer insights into Jerome's conception of the nature of Hebrew text itself, of the relationship between it and the Christian faith, and of his role as translator.
The thesis argues and demonstrates that the language of the IH Psalter reveals influences that derive from Jerome's classical background, from his contact with rabbinic scholars in Palestine, and, especially, from his adopted Christian faith. These influences are subtle, but their combined effect is considerable.
Care is taken to demonstrate that Jerome was a competent translator, and that he deliberately intended the classical, Jewish or Christian nuances that are discussed. This is achieved, first, by comparing the IH Psalter with the Hebrew as an initial step, then with Jerome's translation of the Psalter from the Hexaplaric Septuagint, and with the various Greek versions where they are extant; and second, by evaluating the relationship between Jerome's translations and his exegetical material on the Psalter. The fact that Jerome is both translator and exegete of the Psalter allows clear insight into the impact of his understanding of the Psalms on his translation of them.
The Conclusion argues that the issues can be focussed on and find their resolution in Jerome's conception of the nature and function of the Hebrew text. By imputing to Jerome a belief in the divine inspiration of the Hebrew text, and a belief that the Hebrew text properly understood and properly translated reveals Jesus Christ, the character of the IH Psalter can best be explained. Jerome's translations often exploited available linguistic space, but they rarely went beyond what hebraica veritas could reasonably signify.

Keywords: Jerome
Old Testament
Hebrew
Iuxta Hebraeos
Advisor: Salvesen, A
From Aleshkovsky to Galkovsky

This thesis illustrates and analyses the appeal of folly to writers of, principally, the late- Soviet era (1960s-1980s). This appeal expressed itself not only in numerous portrayals of evidently foolish characters, but also in the widespread use of first-person narrative in which various masks of folly are worn by narrators to assert their detachment from societal norms and from the scholarly and 'objective' discourse which Soviet culture sought to promote. These tendencies towards folly and subjectivity are examined in their various historical, religious and philosophical implications. Parallels are sought both in the Russian literarycultural heritage, which has accorded exceptional importance to various models of folly, and in West-European literary traditions, especially that established by Erasmus. It is argued that, while the Russian paradigm of holy foolery (yurodstvo) has undoubtedly retained its importance as a literary theme and code, loose analogies with yurodstvo may lead to misleading or simplistic interpretations.
In the Introduction I outline further my aims and methodology, while also providing an account of the cultural and literary background to the topic, before and after 1917. In Chapter One I discuss fiction by Vladimir Voinovich, Vasily Shukshin and Venedikt Erofeev, in order to indicate aspects of the general shape of my topic in the given period: how the 'praise of folly' developed and gained in complexity at the end of the 1960s.
The bulk of the thesis (Chapters Two to Five) is devoted to more detailed casestudies of the work of three significant, but critically neglected, writers: Yuz Aleshkovsky, Yury Mamleev and the philosopher, Dmitry Galkovsky. The varied 'fool narratives' of each of these writers manifests, in contrasting ways, a profound and paradoxical engagement with the mind, wisdom and learning. If Aleshkovskian folly develops in a sharply drawn historical context (Stalinism and its aftermath) and bears a markedly Christian flavour, Mamleev seeks to exclude Soviet and Christian thematics entirely, seeking deliverance from thought and reason. Dmitry Galkovsky, meanwhile, assesses the entire history of the Russian intelligentsia's love affair with folly from his own radically subjective and unreliable perspective in his 'philosophical novel' Beskonechnyi tupik.
The Epilogue is devoted to Viktor Erofeev's highly cynical interpretation of Russia's 'praise of folly', before concluding with examples of the renewal of its traditions in post- Soviet prose.

Advisor: Kelly, C
Fabrication, testing and modelling of palladium membranes for fuel cell applications

Increasing carbon emissions and insecurities in oil supply have led to heightened interest in hydrogen powered fuel cells. Preferably, the cell runs on hydrogen gas, though due to the sensitivity of the catalytic components in the fuel cell to carbon monoxide, the hydrogen must be extremely pure (typically <50 ppm CO). Due to a lack of hydrogen infrastructure, it is envisaged that a medium term solution will be the reforming of more conventional fuels such as gasoline. The gas mixture produced however, contains impurities such as CO, CO2 and CH4. Purification may be achieved using palladium membranes, which allow selective permeation of hydrogen. This thesis describes the research carried out in conjunction with Johnson Matthey on thin (typically 7.5 μm) palladium/silver alloy membranes supported on both ceramic and stainless steel porous tubular substrates. Extensive experimental flow testing has been performed to assess the effect of temperature, feed composition, including wet feeds, and membrane thickness on the hydrogen purification properties. An existing Fortran based model was validated and revised to accurately account for the effects of operating conditions such as temperature and carbon monoxide concentration. This work provided excellent correlation between experimental and simulated results. The validated and improved model was incorporated in the design of a hydrogen refuelling station in Aspen Plus and the palladium membrane requirements assessed to supply 650 fuel cell vehicles per day. The system incorporated a steam reformer, membrane clean-up module, water trap and high pressure compressor for hydrogen storage at 1000 bara. Operating conditions such as system pressure, fuel feed and steam to carbon ratio were investigated and adjusted to optimise the overall system efficiency. An efficiency of 52% was achieved with a steam to carbon ratio of SCR = 2.5. A membrane requirement of 6000 standard tubes was found to provide a 90% hydrogen recovery efficiency.

Advisor: Stone, R
Evolutionary patterns derived from 150 million years of morphological and functional evolution in neopterygian fishes

Neopterygian fishes represent over half of vertebrate richness in the Recent and display staggering phenotypic variety, yet little is known about the first 150 million years of their evolution. Furthermore, neopterygian richness and disparity is highly unevenly partitioned between teleost fishes, with ~29,000 species expressing a plethora of phenotypes, and holostean fishes, with 8 species and just two morphological styles. Fossil phenotypes have the unique ability to illuminate the assembly of neopterygian disparity, and can reveal the pattern by which the uneven partitioning of disparity arose.
Morphology and function were quantified with landmarks and six functional traits, respectively, for 356 neopterygian species known globally throughout the first 150 million years of their history. The main axes of morphological and functional variation were derived and used to examine a series of evolutionary questions. Pertinently, they revealed how disparity was accumulated for 60% of the neopterygian radiation; morphological disparity increased through time, whereas functional disparity remained stable.
The morphological dataset was expanded to include shape data for 398 species and size data for 471 species. Time scaled supertrees containing 671 mostly Mesozoic, but also living neopterygian species, were created. Together, the trees and traits were used to quantify evolutionary rates and innovation and test the predictions of genome duplication enhanced morphological diversification in teleosts, and the presence of 'living fossil' characteristics in holosteans. The analyses revealed higher rates and greater innovation in teleosts guaranteed to possess duplicated genomes, consistent with the predictions of genome duplication enhanced diversification. The only 'living fossil' characteristic of holosteans is their poor capacity for size innovation, yet they possess relatively high rates of shape evolution. However, estimates of rates and innovation are heavily influenced by timescale choice, emphasising the need for workers to perform their analyses on a variety of plausible timescales to determine the limits of their conclusions.

Keywords: neopterygii
fossil fishes
neopterygian fishes
genome duplication
Advisor: Friedman, M
Essays in macroeconomic modelling with frictions and rigidities

This thesis presents three dynamic stochastic general equilibrium models to answer three macroeconomic questions. In each model, I impose one or more frictions or constraints and analyse how these frictions affect macroeconomic dynamics.
Chapter 2 studies the coordination of fiscal and monetary policies under optimal commitment and discretion policies under a New Keynesian framework. The chapter shows that when there is indexation in price setting which depends on the lagged output gap as in Steinsson (2003), under the optimal commitment policy, both fiscal and monetary policies have active roles in inflation stabilisation, even although debt follows a unit-root process. Under the optimal discretion policy, both fiscal and monetary policies have active roles in inflation stabilisation to drive debt back to the pre-shock level, consistent with Leith and Wren-Lewis (2008). Extending the model to include capital accumulation does not alter these results.
Chapter 3 presents a microfounded two-country model of global imbalances and debt deleveraging. During global imbalances a sustained rise in saving in one country can lead to a worldwide fall in the interest rates and an accumulation of debt in the other country. When an ensuing deleveraging shock occurs as a result of the global financial crisis, the interest rates are forced further down. I show that in the presence of a liquidity trap the deleveraging country may face a combination of a large fall in output, deflation and real exchange rate appreciation, as a result of debt deflation.
Chapter 4 adds a highly-leveraged financial sector to the Ramsey model and shows that this augments the macroeconomic effects of aggregate productivity shocks. My model is built on the financial-accelerator approach of Bernanke, Gertler and Gilchrist (BGG), in which leveraged goods-producers borrow from a competitive financial sector. In this chapter, by contrast, financial institutions are leveraged and subject to idiosyncratic productivity shocks. They obtain funds by paying an interest rate above the risk free rate, and this risk premium is anti-cyclical, and so amplifies the shocks. My parameterisation, based on US data, is one in which the leverage of the financial sector is two and a half times that of the goods-producers in the BGG model. This causes a much more significant augmentation of aggregate productivity shocks than that found in the BGG model.

Keywords: DSGE modelling
Advisor: Vines, D
The adult neural stem cell niche in ischaemic stroke

Ischaemic stroke is a major cause of mortality and chronic disability for which there is no effective treatment. The subventricular zone (SVZ) is an adult neurogenic niche which mediates limited endogenous repair following stroke. To harness this phenomenon for therapy, it is important to understand how the SVZ niche is altered in stroke, and the processes that recruit neural precursors to the site of injury, which becomes a de facto neurogenic niche. Galectin-3 (Gal-3) is a β-galactoside binding protein involved in cellular adhesion, inflammation and tumour metastasis. Gal-3 is specifically expressed in the SVZ and maintains neuroblast migration to the olfactory bulb, although its role in post-stroke neurogenesis is not well-understood. Therefore, this project aimed to (1) characterise the cytoarchitecture of the SVZ in response to stroke, and (2) examine the role of Gal-3 in stroke outcome and tissue remodelling, and test the hypothesis that Gal-3 is required for neuroblast ectopic migration into the ischaemic striatum.
Using the intraluminal filament model of middle cerebral artery occlusion (MCAO) in mice, and whole mounts of the lateral ventricular wall, significant SVZ reactive astrocytosis and increased vascular branching were observed, thereby disrupting the neuroblast migratory scaffold. Stroke increased SVZ cell proliferation without increase in cell death. Post-stroke ependymal cells were enlarged and non-proliferative, and assumed a reactive astroglial phenotype, expressing de novo high levels of glial fibrillary acidic protein. This was associated with focal planar cell polarity misalignment, and turbulent and decreased rate of cerebrospinal fluid flow. These findings demonstrate significant changes in multiple SVZ cell types which are positioned to influence post-stroke neurogenesis and regulation of the neural stem cell niche
Gal-3 was up-regulated in the ischaemic brain and ipsilateral SVZ. To elucidate the role of Gal-3 after stroke, MCAO was performed in wildtype and Gal-3 null (Gal-3-/-) mice, and parameters of stroke outcome and post-stroke neurogenesis compared. The deletion of Gal-3 did not affect infarct volumes or neurological outcomes, although neuroblast migration into the ischaemic striatum was increased in Gal-3-/- brains. Gal-3-/- mice failed to mount an angiogenic response in the ischaemic striatum, and this was associated with lower levels of vascular endothelial growth factor (VEGF) and increased anti-angiogenic protein levels. Loss of Gal-3 further disrupted the pro-proliferative neural-vascular interaction at the basement membrane. The current data indicate that Gal-3 is a pleiotropic molecule which has distinct roles in both the SVZ and the post-stroke striatum as niches of adult neurogenesis.

Keywords: svz
neuroblast migration
ependymal cells
stroke
galectin-3
MCAO
gal-3
cerebral ischaemia
stem cells
subventricular zone
CSF
Advisor: Szele, F
A study of selected British and European flint assemblages of Late Devensian and Early Flandrian Age

This dissertation is concerned with the analysis of selected blade assemblages from Late Devensian and Early Flandrian contexts in Southern Britain (c. 12,500 - 9,000 BP). The British sites studied are divided into three main groupings: Upper Palaeolithic, Long Blade, and Mesolithic, each of which contains material of a typologically and technologically distinct nature. Despite previous important studies in the British Upper Palaeolithic and Mesolithic, no major work until now has been undertaken on the third technology, that of the Long Blade sites, which seems to occupy a chronological position intermediate between the other two. The dissertation incorporates the first comprehensive description of material from Long Blade sites and contrasts it with the sets of artefacts from the other two groups. Comparative data from the Upper Palaeolithic and Mesolithic derive mainly from primary information recovered in two excavations directed by myself at Hengistbury Head between 1980-4.
The chapters consider the archaeological material in chronological order beginning in Chapter 1 with the Late Upper Palaeolithic assemblage from Hengistbury Head. Chapters 2 and 3 are devoted to the Long Blade assemblages from Britain and Northwestern Europe, whilst in the fourth chapter the Early Mesolithic material from Hengistbury and related sites in Southern Britain is considered. The fifth and last chapter is given over to discussion and final conclusions. Appended to the last chapter is a gazetteer of 159 specified Long Blade findspots in Southern Britain, the first time this material has ever been gathered together. Explanatory notes and a key are provided at the front of the Gazetteer.
In studying the artefacts I have laid particular emphasis on technology as well as typology, and in studying technology I have been particularly influenced by my own work on the experimental manufacture and use of implements. Given that my two excavated sites were very little disturbed, I have also been able to make major use of conjoining artefacts, not only as an aid to understanding the differing techniques of artefact manufacture, but also in interpreting the archaeology of the sites. Some use was also made of experimental taphonomy. These aspects of my work are referred to in the text, notably in Chapters 1 and 4.
The role of IL-18 in intestinal immune regulation

Elevated levels of the cytokine interleukin-18 (IL-18) are found in many chronic inflammatory disorders, including inflammatory bowel disease (IBD). However, the role of IL-18 in mucosal immunity and inflammation is not well understood. At mucosal and environmental interfaces, Th17 cells have been shown to contribute to protection from pathogenic infection. In contrast, regulatory T (Treg) cells maintain intestinal homeostasis by preventing aberrant inflammatory responses to the resident microbiota. We demonstrate that under homeostatic conditions, colonic Th17 cells highly express IL-18 receptor (IL-18R1) and that intestinal epithelial cell production of IL-18 acts directly on CD4+ T cells to limit colonic Th17 differentiation. Furthermore, whilst IL-18R1-signalling is dispensable for induction of colitis, we observed a critical role for IL-18R1-signalling in Foxp3+ Treg mediated control of colitis. Together, these studies demonstrate that the intestinal epithelium regulates colonic CD4+ T cell responses through production of the cytokine IL-18.

Keywords: intestine
Foxp3
IL-18
Th17
immunity
Advisor: Maloy, K
Klenerman, P
Graphical representation of independence structures 

In this thesis we describe subclasses of a class of graphs with three types of edges, called loopless mixed graphs (LMGs). The class of LMGs contains almost all known classes of graphs used in the literature of graphical Markov models. We focus in particular on the subclass of ribbonless graphs (RGs), which as special cases include undirected graphs, bidirected graphs, and directed acyclic graphs, as well as ancestral graphs and summary graphs. We define a unifying interpretation of independence structure for LMGs and pairwise and global Markov properties for RGs, discuss their maximality, and, in particular, prove the equivalence of pairwise and global Markov properties for graphoids defined over the nodes of RGs. Three subclasses of LMGs (MC, summary, and ancestral graphs) capture the modified independence model after marginalisation over unobserved variables and conditioning on selection variables of variables satisfying independence restrictions represented by a directed acyclic graph (DAG). We derive algorithms to generate these graphs from a given DAG or from a graph of a specific subclass, and we study the relationships between these classes of graphs. Finally, a manual and codes are provided that explain methods and functions in R for implementing and generating various graphs studied in this thesis.

Keywords: MC graph
bidirected graph
composition property
graphoid
independence model
summary graph
global and pairwise Markov property
chain graph
ancestral graph
directed acyclic graph
separation criterion
undirected graph
maximality
marginalisation and conditioning
Advisor: Lauritzen, S