91 resultados para S0 Galaxies


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This thesis is a study of Konrad Bayer's dramatic texts. It has evolved out of various attempts to read those texts, some filed and some more successful. It does not claim to be authoritative or complete, since the nature of Bayer's texts, as will become clear in the course of the ensuing chapters, means that they resist such an interpretation. To accept this was an important prerequisite for the writing of this thesis, but a difficult one to fulfill because for the Bayer commentator it constitutes a certain acceptance of defeat even before one begins. Chapter 1 will begin by providing some introductory information about Konrad Bayer, including details of his life and his membership of the Wiener Gruppe, a formative phase in his development as a writer. It will also consider the historical and cultural climate of 1950s Austria that provided the backdrop for Bayer's literary work. The phenomenon of the Wiener Gruppe will then be examined against the background of preceding experimental movements, for the purpose of situating Bayer's work historically and artistically. The aim of this historical and artistic survey is to prepare for the confrontation with Bayer's texts that makes up the other chapters of the thesis. Chapter 2 will constitute a close textual study of one of Bayer's dramatic texts using criteria from the field of text linguistics. Such a study will offer an entry point into Bayer's texts and will supply material which will form the basis for the interpretative investigations of the chapters that follow it. Chapter 3 will consider the influence of language and the individual. In chapter 4 the figure of the Lion of Belfort, a recurring figure in Bayer's dramatic texts, is discussed. The final chapter of this thesis will examine the recurring motifs of violence and cannibalism and will consider them in terms of the findings of preceding chapters.

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The ability of the Gram-positive foodborne pathogen Listeria monocytogenes to survive and grow in environments of elevated osmolarity can be attributed, at least in part, to the accumulation of a restricted range of low molecular mass solutes compatible with cellular function. Accumulated to high internal concentrations in hyper-saline environments, compatible solutes, either transported into the cell or synthesized de novo, play a dual role: helping to stabilize protein structure and function while also counterbalancing external osmotic strength, thus preventing water loss from the cell and plasmolysis. While previous physiological investigations identified glycine betaine, carnitine, and proline as the principal compatible solutes in the listerial osmostress response, genetic alanysis of the uptake/synthesis systems governing the accumulation of these compounds has, until now, remained largely unexplored. Representing the first genetic analysis of compatible solute accumulation in L. monocytogenes, this thesis describes the molecular characterization of BetL; a highly specific secondary glycine betaine transport system, OpuC; a multicomponent carnitine/glycine betaine transporter, and finally proBA; a two-gene operon encoding the first two enzymes of the listerial proline piosynthesis pathway. In addition to their role in osmotolerance, the potential of each system in contributing to listerial pathogenesis was investigated. While mutations in each gene cluster exhibited dramatic reductions in listerial osmotolerance, OpuC- mutants were additionally shown to exhibit reduced virulence when admisistered via the oral route. This represents the first direct link between the salt stress response and virulence in L. monocytogenes.

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Buried heat sources can be investigated by examining thermal infrared images and comparing these with the results of theoretical models which predict the thermal anomaly a given heat source may generate. Key factors influencing surface temperature include the geometry and temperature of the heat source, the surface meteorological environment, and the thermal conductivity and anisotropy of the rock. In general, a geothermal heat flux of greater than 2% of solar insolation is required to produce a detectable thermal anomaly in a thermal infrared image. A heat source of, for example, 2-300K greater than the average surface temperature must be a t depth shallower than 50m for the detection of the anomaly in a thermal infrared image, for typical terrestrial conditions. Atmospheric factors are of critical importance. While the mean atmospheric temperature has little significance, the convection is a dominant factor, and can act to swamp the thermal signature entirely. Given a steady state heat source that produces a detectable thermal anomaly, it is possible to loosely constrain the physical properties of the heat source and surrounding rock, using the surface thermal anomaly as a basis. The success of this technique is highly dependent on the degree to which the physical properties of the host rock are known. Important parameters include the surface thermal properties and thermal conductivity of the rock. Modelling of transient thermal situations was carried out, to assess the effect of time dependant thermal fluxes. One-dimensional finite element models can be readily and accurately applied to the investigation of diurnal heat flow, as with thermal inertia models. Diurnal thermal models of environments on Earth, the Moon and Mars were carried out using finite elements and found to be consistent with published measurements. The heat flow from an injection of hot lava into a near surface lava tube was considered. While this approach was useful for study, and long term monitoring in inhospitable areas, it was found to have little hazard warning utility, as the time taken for the thermal energy to propagate to the surface in dry rock (several months) in very long. The resolution of the thermal infrared imaging system is an important factor. Presently available satellite based systems such as Landsat (resolution of 120m) are inadequate for detailed study of geothermal anomalies. Airborne systems, such as TIMS (variable resolution of 3-6m) are much more useful for discriminating small buried heat sources. Planned improvements in the resolution of satellite based systems will broaden the potential for application of the techniques developed in this thesis. It is important to note, however, that adequate spatial resolution is a necessary but not sufficient condition for successful application of these techniques.

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The dissertation proposes that one of the more fruitful ways of interpreting Burke's work is to evaluate him as an oral performer rather than a literary practitioner and it argues that in his voice can be heard the modulations of the genres and conventions of oral composition of eighteenth-century Gaelic Ireland. The first chapter situates Burke in the milieu of the Gaelic landed class of eighteenth-century Ireland. The next chapter examines how the rich oral culture of the Munster Gaelic gentry, where Burke spent his childhood days, was to provide a lasting influence on the form and content of Burke's work. His speeches on the British constitution are read in the context of the historical and literary culture of the Jacobites, specifically the speculum principis, Párliament na mBán. The third chapter surveys the tradition of Anglo-Irish theoretical writings on oratory and discusses how Burke is aligned with this school. The focus is on how Burke's thought and practice, his 'idioms', might be understood as being mediated through the criterion of orality rather than literature. The remaining chapters discuss Burke's politics and performance in the light of Gaelic cultural practices such as the rituals of the courts of poetry, the Warrant Poems or Barántas; the performance of funeral laments and elegies, Caoineadh, the laments for the fallen nobility, Marbhna na daoine uaisle, the satires and the political vision allegories of Munster, Aislingí na Mumhan; to show how they provide us with a remarkable context for discussing Burke's poetical-political performance. In hearing Burke's voice through the body of Gaelic culture our understanding of Burke's position in the wider world of the eighteenth century (and hence his meaning) is profoundly affected.

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The research described in this thesis involves the synthesis of α-diazo-β-oxo sulfoxides, and exploration of their reactivity. The first chapter includes an introduction to diazocarbonyl chemistry, specifically focusing on the synthesis of diazo compounds, and diazosulfoxide derivatives. The chemistry of sulfines, in particular the generation of α-oxo sulfines and their subsequent trapping as cycloadducts and dimerisation is discussed. The results of this research are discussed in the second and third chapters. The design, synthesis and reactivity of α-diazo-β-oxo sulfoxides is described in chapter 2 where diazo transfer adjacent to sulfoxides to form stable α-diazo-β-oxo sulfoxides has been achieved in cyclic systems. Decomposition of theses α-diazosulfoxides using rhodium carboxylate or carboxamide catalysts is also described. These processes proceed via a Wolff type rearrangement to form α-oxo sulfine intermediates, which were trapped as cycloadducts with dienes. In the absence of a diene trap, dimerisation of the sulfine intermediate was observed. Intramolecular C-H insertion reasctios of α-diazo-α-sulfonyl esters to form substituted sulfolane esters is described in chapter 3. The reactivity of these sulfolane esters is briefly explored. The fourth chapter contains the experimental details and the spectral and analytical data for all new compounds reported.

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The lives of Thomas and Anna Haslam were dedicated to the attainment of women's equality. They were feminists before the word was coined. In an era when respectable women were not supposed to know of the existence of prostitutes, Anna became empowered to do the unthinkable, not only to speak in public but to discuss openly matters sexual and to attack the double standard of sexuality which was enshrined in the official treatment of prostitutes. Their life-long commitment to the cause of women's suffrage never faltered, despite the repeated discouragement of the fate of bills defeated in the House of Commons. The Haslams represented an Ireland which did not survive them. While they were dedicated to the union with Westminster, they worked happily with those who applied themselves to its destruction. Although in many ways they exemplified the virtues of their Quaker backgrounds, they did not subscribe to any organised religion. Despite living in straitened circumstances, they were part of an urban intellectual elite and participated in the social and cultural life of Dublin for over fifty years. It is tempting to speculate how the Haslams would have fared in post independence Ireland. Hanna Sheehy Skeffington who had impeccable nationalist credentials, was effectively marginalised. It is likely that they would have protested against discriminatory legislation in their usual law abiding manner but, in a country which quickly developed an overwhelmingly Roman Catholic ethos, would they have had a voice or a constituency? Ironically, Thomas's teaching on chastity would have found favour with the hierarchy; his message was disseminated in a simple and more pious manner in numerous Catholic Truth Society pamphlets. The Protestant minority never sought to subvert the institutions of the state, was careful not to criticise and kept its collective head down. Dáil Éireann was not bombarded with petitions for the restoration of divorce facilities or the unbanning of birth control. Those who sought such amenities obtained them quietly 'in another jurisdiction.' Fifty years were to pass before the condom wielding 'comely maidens' erupted on to the front pages of the Sunday papers. They were, one imagines, the spiritual descendants of the militant rather than the constitutional suffrage movement. "Once and for all we need to commit ourselves to the concept that women's rights are not factional or sectional privileges, bestowed on the few at the whim of the many. They are human rights. In a society in which the rights and potential of women are constrained no man can be truly free." These words spoken by Mary Robinson as President of Ireland are an echo of the principles to which the Haslams dedicated their lives and are, perhaps, a tribute to their efforts.

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This thesis is concerned with several aspects of the chemistry of iron compounds. The preparation (with particular emphasis on coprecipitation and sol-gel techniques) and processing of ferrites are discussed. Chapter 2 describes the synthesis of Ni-Zn ferrites with various compositions by three methods. These methods include coprecipitation and sol-gel techniques. The Ni-Zn ferrites were characterised by powder X-ray diffactometry (PXRD), scanning electron microscopy (SEM), vibrating sample magnetometry (VSM), Mössbauer spectroscopy and resistivity measurements. The results for the corresponding ferrites prepared by each method are compared. Chapter 3 reports the sol-gel preparation of a lead borosilicate glass and its addition to Ni-Zn ferrites prepared by the sol-gel method in Chapter 2. The glass-ferrites formed were analysed by the same techniques employed in Chapter 2. Alterations in the microstructure, magnetic and electronic properties of the ferrites due to glass addition are described. Chapter 4 introduces compounds containing Fe-O-B, Fe-O-Si or B-O-Si linkages. The synthesis and characterisation of compounds containing Fe-O-B units are described. The structure of [Fe(SALEN)]2O.CH2Cl2 (17), used in attempts to prepare compounds with Fe-O-Si bonds, was determined by X-ray crystallography. Chapter 4 also details the synthesis of three new borosilicate compounds containing ferrocenyl groups, i.e. [FcBO)2(OSiBut2)2] (19), [(FcBO)2(OSiPh2)2] (20) and [FcBOSiPh3] (21). The structure of (19) was determined by X-ray Crystallographic analysis. Chapter 5 reviews the intercalation properties of the layered host compound iron oxychloride (FeOCI). Intercalation compounds prepared with the microwave dielectric heating technique are also discussed. The syntheses of intercalation compounds by the microwave method with FeOCI as host and ferrocene, ferrocenylboronic acid and 4-aminopyridine as guest species are described. Characterisation of these compounds by powder X-ray diffractometry (PXRD) and M{ssbauer spectroscopy is reported. The attempted synthesis of an intercalation compound with the borosilicate compound (19) as guest species is discussed. Appendices A-E describe the theory and instrumentation involved in powder X-ray diffractometry (PXRD), scanning electron microscopy (SEM0, vibrating sample magnetometry (VSM), Mössbauer spectroscopy and electrical resistivity measurements, respectively. Appendix F details the attempted syntheses of compounds with Fe-O-B and Fe-O-Si linkages.

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The present work is an exploration of the beliefs and practices of three lay Catholic devotional communities in and around the city of Cork, Ireland. The research is guided by the theory that folk, or popular, religion is a dynamic process in which individuals and groups utilise the resources of orthodoxy, popular tradition, and personal creativity, to better interpret, articulate, and create religious experiences. Ethnographic fieldwork was the principal method of data collection. Four areas of folk religion are given special attention: the use of religious narrative to represent and reproduce religious experience, the use of material artefacts to create channels for sacred presence and activity, the use of ritual and pilgrimage to establish sacred time and space, and the use of prayer to accomplish all of these goals. These sections are followed by a more holistic analysis of the material, a critical examination of the work, and suggestions for further research.

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This study examined the spatial and temporal variability of dung beetle assemblages across a variety of scales e.g. from the between-pad scale (examining the effects of dung size and type) to larger spatial scales encompassing southern Ireland. Dung beetle assemblage structure as sampled by dung pad cohort samples and dung baited pitfall trapping were compared. Generally, the rank order of abundance of dung beetle species was significantly correlated between pitfall catches and cohort pad samples. Across different dung sizes, in both pitfall catches and cohort pad samples, the relative abundance of species was frequently significantly different, but the rank order of abundance of dung beetle was usually significantly correlated. Considerable variations in pitfall catches at temporal scales of a few days appeared to be closely related to weather conditions and rotational grazing. However, despite considerable variation in absolute abundances between consecutive days of sampling, assemblage structure typically remained very similar. The relationship between dung pad size and dung beetle colonisation was investigated. In field experiments in which pads of different sizes (0.25 L, 0.5 L, 1.0 L and 1.5 L) were artificially deposited, there was a positive relationship between pad size and both biomass and number of beetles colonising dung pads and pitfall traps. In addition, with one exception, the field experiments indicated a general positive relationship between dung pad size and biomass density (dung beetle biomass per unit dung volume). A laboratory experiment indicated that pat residence times of A. rufipes were significantly correlated with dung pad size. Investigation of naturally-deposited cow dung pads in the field also indicated that both larval numbers and densities were significantly correlated with dung pad size. These results were discussed in the context of theory related to aggregation and coexistence of species, and resource utilisation by organisms in ephemeral, patchy resources. The colonisation by dung beetles of dung types from native herbivores (sheep, horse and cow) was investigated in field experiments. There were significant differences between the dung types in the chemical parameters measured, and there were significant differences in abundances of dung beetles colonising the dung types. Sheep dung was typically the preferred dung type. Data from these field experiments, and from published literature, indicated that dung beetle species can display dung type preferences, in terms of comparisons of both absolute and relative abundances. In addition, data from laboratory experiments indicate that both Aphodius larval production and pat residence times tended to be higher in those dung types which were preferred by adult Aphodius in the colonisation experiments. Data from dung-baited pitfall trapping (from this and another study) at several sites (up to 180 km distant) and over a number of years (between 1991 and 1996) were used to investigate spatial and temporal variation in dung beetle assemblage structure and composition (Aphodius, Sphaeridium and Geotrupes) across a range of scales in southern Ireland. Species richness levels, species composition and rank order of abundances were very similar between the assemblages. The temporal variability between seasons within any year exceeded temporal variability between years. DCA ordinations indicated that there was a similar level of variability between assemblage structure from the between-field (~1km) to regional (~180 km) spatial scales, and between year (6 years) temporal scales. At the biogeographical spatial scale, analysis of data from the literature indicated that there was considerable variability at this scale, largely due to species turnover.

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Cross-cultural variations in conceptions of childhood are discussed, particularly with regard to child abuse and child labour. Regardless of cultural background, a universal minimum standard of child rearing is required. The street child literature is reviewed, culminating in an analysis of Ethiopian street children. Theoretically this work is informed by victimology. Concepts shared by victimology and rational choice perspective are discussed, after Fattah (1993a). Victim surveys are described, highlighting their accuracy of crime estimates. Juvenile prostitution, runaways and rape are examined, particularly with regard to their relevance in Addis Ababa. Fifty five male and 135 female street children were interviewed. Interviews with boys focused on delinquency. An age-related pattern emerged, with younger boys less likely to drink, chew khat, steal or be sexually active. Interviews with street girls focused on the differences between girls living on the streets (girls of the street), girls working on the streets (girls on the street) and a sample of homebased girls. Girls of the street come to the street come to the streets for many reasons. Conflicts with a parent or guardian account for almost 50%. They are highly vulnerable to sexual assaults, particularly those 43% who have worked as prostitutes. Girls on the street experience considerably less victimisation. Urban poor girls live in socio-economic circumstances akin to girls on the street but enjoy almost universal protection from victimisation because they do not spend time on the streets. Unprotected by the stability which a family provides, girls of the street experience high victimisation levels. Such victimisation is often the result of reliance on types of work, such as prostitution, which brings the girls into contact with exploitative adults. Resistance to such victimisation is provided by a secure place to sleep, companions, and relatively safe types of work. Such protective factors are more readily available to family based children as compared to those living independently.

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Zakes Mda, dubbed one of South Africa's most prolific playwrights, produced his richest and most powerful theatre work during the 70s and 80s. Ironically, it is only in the 90s that he has been acknowledged in his own country as one of its foremost dramatists - ironic since he has recently moved away from drama into the realms of fiction. Fortunately Mda has accumulated a worthy canon of dramatic works, spanning radio and film, as well as theatre, and there is no reason to believe that he will not return to play writing. Mda has worked extensively in theatre in various capacities but most notably in the area of theatre-for-development. For example, he worked as director with Maratholi Travelling Theatre in Lesotho, an experience which contributed, in part, towards his book "When People Play People: Development Communication Through Theatre". Mda's plays have been produced in the United States, Britain, Spain, France and Russia as well as in southern Africa. "The Nun's Romantic Story" has been translated into Castilian and Catalan and "We Shall Sing for the Fatherland" and "Dark Voices Ring" have both been translated into Russian and French. In South Africa he won the Merit Award of the Amstel Playwright of the Year Society for "We Shall Sing for the Fatherland" in 1978 and in 1979 he was Amstel Playright of the Year for "The Hill". For his novel "She Plays with the Darkness", he won the Sanlam Literary Award in 1995.

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Accepted Version

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Vaccinia virus, the prototype member of the orthopoxviruses, is the largest and the most complex virus known. After replication of its genome and expression of the viral proteins, vaccinia undergoes a complicated assembly process which produces two distinct infectious forms. The first of these, the intracellular mature virus (IMV), develops from the immature virion (IV) after packaging of the genome and cleavage of the core proteins. During the transition of the IV to the IMV, a new core structure develops in the centre of the virion, concomitantly with the appearance of spike-like structures which extend between this core and the surrounding membranes of the IMV. I describe the characterization of p39 (gene A4L) which is hypothesized to be one component of these spikes. p39 is a core protein, but has strong associations with the membranes surrounding the IMV, possibly due to an interaction with p21 (A17L). Due to its location between the core and the membranes of the IMV, p39 is ideally situated to act as a matrix-like linker protein and may play a role in the formation of the core during the transition of the IV to the IMV. The IMV is subsequently wrapped by a membrane cisterna derived from the trans Golgi network, to form the intracellular enveloped virus (IEV). I show that the IEV can co-opt the actin cytoskeleton of the host cell in order to induce the formation of actin tails which extend from one side of the virion. These actin tails propel the virus particle, both intra- and intercellularly, at speeds of up to 2.8µm/min. On reaching the plasma membrane, the virus particles project out from the cell surface at the tip of virally induced microvilli. The outer membrane of the IEV is thought to fuse with the plasma membrane at the tip of these projections, thus exposing the second infectious form of vaccinia. This is thought to be the means by which the cell-associated enveloped virus is presented to neighbouring cells, thereby facilitating the direct cell-to-cell spread of virus particles.

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A model for representing music scores in a form suitable for general processing by a music-analyst-programmer is proposed and implemented. Typical input to the model consists of one or more pieces of music which are encoded in a file-based score representation. File-based representations are in a form unsuited for general processing, as they do not provide a suitable level of abstraction for a programmer-analyst. Instead, a representation is created giving a programmer's view of the score. This frees the analyst-programmer from implementation details, that otherwise would form a substantial barrier to progress. The score representation uses an object-oriented approach to create a natural and robust software environment for the musicologist. The system is used to explore ways in which it could benefit musicologists. Methodologies for analysing music corpora are presented in a series of analytic examples which illustrate some of the potential of this model. Proving hypotheses or performing analysis on corpora involves the construction of algorithms. Some unique aspects of using this score model for corpus-based musicology are: - Algorithms impose a discipline which arises from the necessity for formalism. - Automatic analysis enables musicologists to complete tasks that otherwise would be infeasible because of limitations of their energy, attentiveness, accuracy and time.

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The research described in this thesis involved the synthesis and characterisation of rhodium, platinum and palladium derivatives of arsena-, carba- and telluraboranes.