VictorJuiz/thesis huggingface dataset:
The role of acidity in tumour development

Acidic pH is a common characteristic of human tumours. It has a significant impact on tumour progression and response to therapies. In this thesis, we utilise mathematical modelling to examine the role of acidosis in the interaction between normal and tumour cell populations. In the first section we investigate the cell–microenvironmental interactions that mediate somatic evolution of cancer cells. The model predicts that selective forces in premalignant lesions act to favour cells whose metabolism is best suited to respond to local changes in oxygen, glucose and pH levels. In particular the emergent cellular phenotype, displaying increased acid production and resistance to acid-induced toxicity, has a significant proliferative advantage because it will consistently acidify the local environment in a way that is toxic to its competitors but harmless to itself. In the second section we analyse the role of acidity in tumour growth. Both vascular and avascular tumour dynamics are investigated, and a number of different behaviours are observed. Whilst an avascular tumour always proceeds to a benign steady state, a vascular tumour may display either benign or invasive dynamics, depending on the value of a critical parameter. Extensions of the model show that cellular quiescence, or non-proliferation, may provide an explanation for experimentally observed cycles of acidity within tumour tissue. Analysis of both models allows assessment of novel therapies directed towards changing the level of acidity within the tumour. Finally we undertake a comparison between experimental tumour pH images and the models of acid dynamics set out in previous chapters. This analysis will allow us to assess and verify the previous modelling work, giving the mathematics a firm biological foundation. Moreover, it provides a methodology of calculating important diagnostic parameters from pH images.
The responses of the saw-toothed grain beetle Oryzaephilus surinamensis to pheromones and food odours

The responses of the saw-toothed grain beetle, 0ryzaephilus surinamensis to food odours and pheromones were investigated at both sensory and behavioural levels to give an integrated picture of olfaction, and the importance of odours in this species.
The sensory capability of the antenna was assessed by a study of the structure, distribution and function of sensilla using SEM and TEM. Seven different sensilla types, including 3 with an olfactory function, were identified, although the total number of olfactory sensilla was low compared with those for mechanoreception.
Antennal responses to odours were studied using both the electroantennogram (EAG) technique and single-cell recordings, whilst a 2-choice pitfall assay and a single-insect arena test were used to investigate behavioural responses.
Food-produced volatiles from carob pods were found to produce large amplitude antennal responses and attraction in behavioural assays. Analysis of such volatiles by coupled gas chromatography-electroantennography (GC-EAG) demonstrated at least 3 active components, of which one was identified as hexanoic acid. Attraction to food odour was found to vary with insect age, and this correlated with similar variation in the EAG response, suggesting a role for peripheral receptor sensitivity in modulating insect behaviour.
Beetle-produced volatiles also caused antennal responses and attraction of conspecific individuals of both sexes, thus acting as an aggregation pheromone. The active components were identified by GC-EAG as (Z,Z)-3,6-dodecadien-11-olide, (Z,Z)-3,6-dodecadienolide and (Z,Z)-5,8-tetradecadien-13-olide. These act as a multicomponent pheromone, with separate antennal receptors for each component. Although no sexual differences in antennal responses were found, consistently more females than males were attracted to the pheromone. This suggested a partial sex pheromone function, as the pheromone was shown to be male-produced. However, the ratio of females:males attracted was found to vary with the blend ratio tested. Thus if males are able to alter the blend they produce, the pheromone may act at different times as either a sex pheromone or an aggregation pheromone.
Finally, the functional and evolutionary importance of odours to this insect are discussed.

Advisor: Simpson, S
Compelling identities

In Ireland's divided society in which everything is political except solutions, the evaluation and redefinition of the governing metaphors of political and cultural identity is a matter of public concern. For nationalist Ireland, the traditional centrality of the poetic imagination to the development of the legitimating tropes of national identity endows representative status upon all subsequent poetry which treats of these themes. The heated public and critical debate about the poetry of Seamus Heaney derives from the recognition that as nations are "imagined communities", so the form and content of the poet's imaginative process is heavy with political and social implications.
Heaney's poetic negotiation between the given collective traditions of his community and the transfigurative appeal of the individual imagination engaged with modernity, produces a sustained reflection upon the nature and implications of cultural identity in modern Ireland. What is implict in the tenor of the debate surrounding Heaney is explicit in Heaney f s compelling poetic, namely, that in the modern age cultural identity remains central to social and political definition.
But whereas the fact of cultural identity is central to social definition, the form (either hegemonic or inclusivist) of any such expression of identity is dependent upon the discursive practices which imagine and construct such definitions. In this context what begins for Heaney as a lyric flirtation with the possibilities of language, becomes a critical reappraisal of nationalist ideology's governing metaphors of place, history and belonging.
In order to situate and define Heaney's contribution to the preoccupying question of identity it is necessary to evaluate the history and discursive evolution of nationalism as an ideology. Such an evaluation demonstrates that nationalism as a product of post-dynastic modern societies, is dependent upon a number of figurative habits and discursive practices for its universal and universalising appeal. By identifying these formations and by establishing the connection between these figures of thought and the expression of cultural identity as a hegemonic or inclusivist narrative, criteria may be determined against which the status of Heaney's own expressions of cultural identity may be assessed.
Against the contemporary background in which nationalism appears to have acquired the status of a political metaphysics, Heaney's candid engagement with the cherished illusions informing this perception reveals him for what he is - a definitively modern poet announcing to those who will listen that there is and must be, poetry after Auschwitz.
British interests in the Falkland Islands

The aim of the thesis is to study the circumstances which influenced the policy of the British Government towards the decolonization of the Falklands from 1945 to 1989. A comprehensive approach to the subject enabled an examination of the inter-relationship between the various forces which defined the nature of the dilemma. The themes included economic development, the form of landownership in the Colony, Falkland politics, the strategic value of the Islands, Anglo- Argentine trade and the Antarctic dimension.
The thesis presents an original interpretation of how volatile and unpredictable pressures defined the dispute. A pattern emerges which shows that Government policy consisted of responses to different situations. The structure is based on a chronological approach which concentrates on the seven major turning-points in the dispute and how they were perceived in Britain and the Falklands. It also includes three original case studies. First, there is a socio- economic study of the peculiar approach to the colonization of the Falklands in the nineteenth century which provides a background to later developments. Secondly, the 1982 Conflict shows how the problems of the last British colonial territories can be in inverse proportion to their size. Thirdly, the examination of the Falkland Lobby gives a detailed account of how a successful British pressure group is organized.
The primary sources used were Foreign and Colonial Office files at the Public Records Office (Kew) for the period up to the 1950s, and the archives of the Falkland Islands Association for the period from the mid-1960s. These were supplemented by private papers, the records of the Falkland Islands Company in London, interviews with prominent people, contemporary newspapers, official documents and secondary sources.
Orbivirus non-structural protein NS2

Bluetongue virus (BTV) is an economically important arthropod-borne virus that causes Bluetongue disease in sheep and other ruminants. BTV is the prototypical orbivirus and is a member of the Reoviridae family. Other arthropod-borne orbiviruses include African horse-sickness virus (AHSV) and epizootic haemorraghic disease virus (EHDV). The virus contains 10 dsRNA segments that encode for both structural and non-structural proteins. The structural proteins of orbiviruses and other members of the Reoviridae, such as reoviruses and rotaviruses, are arranged in a very similar layered arrangement. The roles of the non-structural proteins are largely unknown. This thesis describes the functional characterisation of one of these nonstructural proteins, NS2.
The NS2 protein of BTV-10 was purified to a high degree of homogeneity from insect cells. This purified protein was used in crystal screening experiments and in circular dichroism (CD) experiments. Although a wide range of conditions were tried for crystallography, no crystals were obtained. This may be due to sequence or conformational heterogeneity. Size-exclusion chromatography was used to show that purified NS2 exists in large multimers, supporting the conclusion that conformational heterogeneity was responsible for the lack of crystal formation. CD revealed that NS2 has a high α-helical content.
NS2 is a ssRNA-binding protein. To identify the nucleotides within the viral RNA segments that are important for recognition by NS2, gel-shift and uvcrosslinking experiments with various labelled synthetic RNA probes and in vitro transcripts were performed. Initial gel shift analysis with short synthetic RNAs indicated that NS2 bound a sequence corresponding to the conserved 5' terminus of rotavirus genomic RNA. Similar sequences, called the NS2 target sequence or NTS, were identified in all 10 BTV segments. A number of truncations and deletions of BTV segments M4 and S10 were created to investigate the role of this aptamer in NS2 binding. The results indicate that the NTS is required for the binding of NS2 to each BTV viral RNA segment. These results were confirmed by using short synthetic RNA probes corresponding to the aptamer identified in segments M4 and S10 and by showing that the aptamer could confer NS2 binding to non-BTV RNA.
Further biochemical analysis of NS2 revealed previously undescribed features of the protein. Chemical crosslinking and co-immunoprecipitation studies showed that NS2 can interact with VP1 the viral RNA polymerase. The inclusion of NS2 in in vitro transcription-translation and translation reactions demonstrated a specific shutdown of BTV protein synthesis, suggesting a role for the protein in a switch from viral RNA translation to RNA packaging. This translation inhibition is dependant on the concentration of NS2 present and may be related to the formation of viral inclusion bodies. NS2 was also found to bind nucleotide triphosphates and to have phosphohydrolase activity. Kinase inhibitors were used to identify casein kinase n as the cellular kinase that phosphorylates NS2 in vivo.
The conceptual and material transformation of the villa in Aquitanica Prima from the third to seventh centuries A.D

This thesis explores the reasons behind the apparent lack of physical remains of early mediaeval villas, given the repeated references to 'villae' in contemporary sources. The late Roman province of Aquitanica I, with its ample early mediaeval documentation and strong Gallo-Roman traditions, will be used to test three explanations for this non-concordance of material and literary data; either the problem lies with modern expectations concerning the appearance of early mediaeval 'villae', or with past and present archaeological methodology, or, alternatively, most early mediaeval villas are inacessible to modern excavation because, unlike Roman villas, they evolved into nucleated communities (villages). Whilst none of these theories are mutually exclusive, a strongly critical re-examination of the 'villa- to-village' model forms the core of this study because of the ramifications of its widespread acceptance by modern historians.
After a brief survey of the changing definitions of Aquitanica I itself, the conceptual evolution of the 'villa' will be examined; and since a reliance upon toponymy to locate late Roman and early Merovingian estates is central to the debate surrounding their nature and composition, a detailed analysis of its limitations will follow. In the process, several common generalisations about this period will be tested for eastern Aquitaine: the extent of depopulation, land abandonment, Germanic settlements, and the change from a pattern of dispersed to nucleated settlements, from Roman farmsteads to mediaeval agricultural villages, Finally, a brief summary of the 'archaeology' of the late Roman villa in eastern Aquitaine will be compared with that of its Merovingian counterpart; and the overwhelming conclusion reached, that the problem Is due to past shortcomings in archaeological retrieval rather than the transformation of the villa into village, which is probably a late rather than early Merovingian process, and which certainly cannot be demonstrated for late Roman central Gaul.
Shrapnel motion

When a bomb explodes, the bomb-casing breaks up causing shrapnel fragments to scatter off with high velocity. Whilst study on penetration of the designated target has been addressed, the mechanics involved in the motion of the shrapnel have not been examined in great detail. This dissertation will address shrapnel motion using ideas from gasdynamics. The motivation for this problem comes from QinetiQ who, among other things, play an active role in modelling violent mechanics.
Old Norse visions of the afterlife

The nature of life after death is only tentatively sketched out in the canonical writings of the Christian Church, yet it represents one of the most prominent literary subjects in medieval Europe. The so-called Visiones represent a genre that enjoyed a particularly broad dissemination between the fourth and thirteenth centuries. This study aims to assess the impact of this Latin tradition on Norse-Icelandic authors and processes of cultural appropriation evident in medieval vernacular adaptations of the genre.
The first chapter outlines the historical and theological conditions surrounding the genre’s dissemination in Western Scandinavia and identifies the primary corpus of vernacular adaptations of the genre to be analysed in this study. Chapter II considers the literary contexts in which Visio-conventions have been integrated, highlighting the distinctive generic and creative diversity exhibited in the primary corpus. Chapters III and IV are concerned with the literary motif of the journey to the otherworld and its importance in Old Norse literary traditions across the period of Christianisation. The former examines signs of continuity on a conceptual level between traditional native and Christian narratives about the otherworld, suggesting that the journey motif represented a sustained source of literary creativity in pre- and post-conversion societies. The latter examines this notion of continuity with reference to two significant literary symbols, the otherworld shoe and the otherworld bridge, and their pregnant resonances in Norse Icelandic records of myth, law, and religious ritual; it will here be shown how certain symbols found in vernacular accounts of the afterlife produce a rich set of connotations meaningful within their particular cultural setting. The final Chapter analyses the social mentality encoded in portrayals of the idealised hereafter, and it will be argued that portrayals of eschatological justice and the topography of heaven reflect attitudes characteristic of the societies from which these visions emerge.
The thesis as a whole thereby calls attention to the broad and deep nature of the Visio genre’s impact on Western Scandinavian literary culture, suggesting that this particular genre-oriented study may serve as a case study of the reception of Christian literary traditions in medieval Iceland and Norway more generally.

Keywords: Visiones
Old Norse Literature
Medieval Visions of the Afterlife
Advisor: O'Donoghue, H
The education of children of immigrants in Finland

This thesis considers the education of children of immigrants in Finland, focusing on attainment and transitions around the age of 16. It is the first detailed representative study on the topic in Finland. Compared to international research it is amongst the ones to most fully explore the different aspects of education around this age. For the most part, it is limited to studying structural explanations for differences between students and ethnic groups. The majority of the analyses in the thesis are done using register data. Statistical modelling of this data is done using multivariate regression analyses. The results are supplemented with evidence from interviews with both majority students and children of immigrants. With regards to school achievement at the end of comprehensive school, many immigrant-origin groups are seen to have lower average grades than the majority. However, this is explained by lower parental resources. After controlling for parental resources, very few disadvantages remain. On the other hand, the gender gap evident amongst the majority is not found amongst many immigrant-origin groups. Looking at continuation to upper secondary education compared to dropping out, most children of immigrants are seen to have a higher probability of dropping out than the majority. This is explained by their lower school achievement and higher parental non-employment. Nevertheless, the difference between children of immigrants and the majority remains evident at the very low end of the achievement scale. Considering the choice of upper secondary school type, children of immigrants can be seen to be more likely than the majority to continue to vocational school. Yet, after controlling for prior school achievement and parental resources, almost all immigrant-origin groups are more likely than the majority to continue to general rather than vocational school. Interviews suggest that when considering their school choices, majority students tend to be driven by their interests and see their decision making as being independent of others. On the other hand, children of immigrants tend to have more specific future plans and to take the wishes of their parents more into consideration.

Keywords: education
Finland
children of immigrants
Advisor: Heath, A
Spin-orbit coupling effects in diatomic molecules

Spin-orbit coupling and the related effects of A-doubling and spin-splitting have been well known to spectroscopists for some considerable time. The importance of these phenomena stems from the advent of radioastronomy and the study of the interstellar medium. Identification of the molecules, and the molecular transitions, in the interstellar dust clouds is necessary for an understanding of the cooling process by which these clouds can contract to form new stars.
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Advisor: Richards, W
Short pulse x-ray generation in synchrotron radiation sources

This thesis describes an investigation into the performance of different schemes for generating short x-rays pulses via synchrotron radiation emission. A review is given of the methods that have been previously proposed for this task. From this review, three leading schemes are selected for in-depth investigations, each of which explores the boundary of what is presently achievable in accelerator-based light sources.
The first scheme generates short x-ray pulses by operating an electron storage ring in a quasi-isochronous state using a ‘low-alpha’ lattice. High and low emittance lattices are developed, studied through simulation and then implemented on the Diamond storage ring. Beam dynamics and bunch length measurements are presented for a variety of machine conditions, and an assessment is made of the minimum practically achievable bunch length for stable user operation. Radiation pulses of 1 ps r.m.s. are demonstrated using this scheme.
The second and third schemes investigate performance limits for a linac-based light source through numerical simulations. The first of these generates ultra-short pulses by passing a highly compressed electron bunch through a long undulator to radiate in the ‘single-spike’ regime. A comparison is made with theoretical predictions for the required electron bunch length to operate in this way, which highlights the need for accurate start-to-end simulations. The final scheme generates ultra-short x-ray pulses through laser manipulation of the electron bunches. The modulated electrons pass through a long undulator with tapered gap, such that only the centre of the modulated portion experiences high free-electron laser (FEL) gain. A method to enhance the FEL output from this scheme using a wavelength filter and grating-compressor is investigated. The sensitivity of the two schemes to jitter sources is determined, and it is demonstrated both schemes are capable of generating GW-level, fully coherent sub-fs soft x-ray pulses. Such pulses would open up the development of time-resolved science to new regimes.

Keywords: x-ray
beam dynamics
accelerator
synchrotron radiation
short pulses
Advisor: Bartolini, R
Peach, K