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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

J.H. Prynne in context, 1955-1975

Goddard, Louis January 2017 (has links)
This thesis presents a partial survey of the intellectual and cultural environment in which the contemporary British poet J.H. Prynne began his literary career. Its primary contribution to knowledge consists of a reorientation of critical perspective towards Prynne's early career and its specifically British contexts, as well as a detailed literary-historical account of his relation to those contexts. This account proceeds by analysis of Prynne's prose works rather than his poetry, leading to a secondary contribution in the form of a number of new readings of those works and a consideration of Prynne's attitude towards prose as a form. Extensive use is made of archival material, much of which has not been examined in previous scholarship. The Introduction sets out the methodology of the thesis and argues that existing work on Prynne suffers from interlinked biases against consideration of Prynne's early career and his British influences. Chapter 1 offers an account of a particular network of such influences centred on the University of Cambridge, looking at one regularly cited influence, Donald Davie, and arguing for recognition of a new one in F.R. Leavis. In Chapter 2, Prynne's involvement with the ‘little magazine' scene is considered in detail and an extended reading of his 1967 piece ‘A Note on Metal' is used to reflect on the relationship between prose and its publication contexts. Chapter 3, meanwhile, proposes a third key context for Prynne's early career in the prose fiction of Wyndham Lewis, Edward Upward and Douglas Oliver, before offering a model for Prynne's poetic thinking in this period based on the panspermia hypothesis. The Conclusion attempts to name this model more specifically, while reflecting on the validity of the thesis's semi-biographical approach.
2

An investigation of rotating magnetospheres

Ryan, Richard Daniel January 2002 (has links)
In this thesis we will construct simple models of rotating stellar and planetary magnetospheres within the framework of ideal MHD. These models will take the basic outline of a stellar magnetosphere that we have outlined above as a starting point from which to proceed further. In summary, this simple magnetosphere will be that of a single, rapidly rotating star' with an axisymmetric dipole magnetic field at the base of its corona and with an axis that is in alignment with that of the rotation axis. It is the isothermal plasma associated with this field that will give rise to the magnetospheric emission and which is held in strict corotation with the stellar surface. Equatorial and rotational symmetry reduce the domain to one quarter of a two dimensional quadrant. We will consider timescales that are much longer than the typical time scales of the system, which will allow us to model the evolution of the system quasi-statically by calculating sequences of MHS equilibria. This is achieved by numerical solution of the Grad-Shafranov equation (in terms of the flux function. A) Which requires us to specify a suitable surface pressure distribution and specify the toroidal component of the magnetic field as a function of A. The second chapter will outline the numerical procedure that will be employed to calculate these equilibrium sequences, and the practical realisation of this procedure. The third chapter will discuss different models which will be characterised by different surface pressure distributions but all of which will lack a toroidal magnetic field component. The fourth chapter will discuss results from a model which includes a toroidal magnetic field component. The models successfully reproduce the observed saturation and supersaturation of stellar emission with rotation. The fifth chapter will address the question of analytically constructing three dimensional equilibria that may be of use in the modelling of magnetospheres with magnetic field geometries that are not in alignment with their rotation axes or which are displaced from the centre of the rotating body, such as the giant gas planets Uranus and Neptune. The last section of the thesis will be a brief discussion of our conclusions, a review of the work of the thesis and will consider the outlook for further development, extension and refinement of our models.
3

The acetylation and methylation of starch

Rutherford, Jean Kerr January 1931 (has links)
The colloidal nature of starch, and the high molecular weight of the complex has rendered it impossible to study the constitution of this polysaccharide by other than degradation reactions. Accordingly starch has been hydrolysed in various ways to give dextrins, amyloses, maltose or glucose, according to the method adopted, and the stage at which the reaction was arrested. […] Improved methods of separation have enabled the constitution of those partially methylated glucoses to be fully worked out in the present research, and in this way the order in which methyl groups enter the molecule has been traced. The main programme of the research may therefore be synopsised as under: 1. Attempts to degrade starch by mild ‘acetolysis'. 2. A comparative study of the methylation of starch before and after acetylation. 3. A complete study of the partially methylated glucoses obtained from methylated starch. 4. Determination of the order in which methyl groups enter the starch molecule. 5. The graded hydrolysis of methylated starch.
4

The role of secular discourse in theological anthropology and the doctrine of sin : a comparative study of Alistair McFadyen and Karl Barth

Russell, Edward J. N. January 2003 (has links)
Contemporary theology increasingly is concerned with 'inter-disciplinary dialogue'. There has, however, been little work done on the under-girding structures of such a dialogue. The central concern of this thesis is to explore the methodological foundations for the relation between 'theology' and 'secular discourse'. Although there are many possibilities for testing the relation between theology and secular discourse, theological anthropology and the doctrine of sin are used as the primary testing grounds because they are central to the concerns of much contemporary systematic theology as well as being areas to which the secular world has much to contribute. Alistair McFadyen's and Karl Barth's work in these areas is adopted as the particular focus of the thesis. Together their work offers a rich environment for analysing the methodological issues at stake in the relationship between theology and secular discourse. The primary aim of the thesis is to offer an approach to interdisciplinary dialogue which maintains 'the priority of God' in theological method whilst recognising that engagement with secular discourse enables theology 'to do its job better'. Drawing from McFadyen's and Barth's work in theological anthropology and the doctrine of sin, some methodological foundations for structuring the relation between theology and secular discourse are laid out and stated in a more widely applicable form.
5

Quantification of cell penetrating peptide uptake by fluorescent techniques

Staley, Ben Paul January 2012 (has links)
Cell penetrating peptides have been the focus of drug delivery research for 15 years due to their apparent ability to deliver cargoes inside cells more readily than many other carriers. Using two of the most commonly studied peptides (tat47-57 and R9), the present study differs from previous work by deliberately choosing to observe uptake with lower peptide concentrations closer to potential therapeutic doses, and by implementing raster image correlation spectroscopy (RICS) on a commercial microscope to quantify uptake in parallel to other techniques such as fluorescence correlation spectroscopy (FCS), confocal microscopy, and mass spectroscopy.An initial study using mass spectrometry and ExPASy (Expert Protein Analysis System) revealed that the peptides are stable for at least one hour in PBS. Based on this initial information and other experimental conditions, the study took two main directions with regards to the peptide: the membrane interaction and accumulation in the cell.The peptides interaction with the cell membrane revealed that neither tat-TAMRA nor R9-TAMRA disrupts the membrane of cells: incorporation of FM2-10 in the membrane was not modified in K562 cells whilst it was in presence of the control lytic peptides GALA and mellitin. Based on this information confocal microscopy was utilised to assess the localisation on the cell membrane. Peptide binding to the membrane appeared to be heterogeneous in distribution at 1µM bulk concentration.Accumulation in cells of the peptides was observed incubated at 37°C, confocal microscopy showed punctuated distribution with intracellular aggregations of fluorescence measuring between 2.5-3.5µm in diameter. Co-staining with a nuclear dye revealed these aggregations to be focused around the nucleus of the cell. Initial FCS experiments indicated a concentration dependent accumulation of the peptide in the cells and a decrease of the intracellular diffusion coefficients at high concentration possibly corresponding with molecular crowding. Interestingly the anomalous diffusion model did not statistically improve the results.RICS was implemented to study the kinetics of entry of TAMRA labelled cell penetrating peptides in both Caco-2 and HeLa cells lines at concentrations between 500nM and 2µM. Concentrations above 1µM exhibited higher final intracellular concentrations, yet the measured diffusion coefficients were similarly independent of extracellular concentration. Both peptides appeared to enter the cell quickly with a fast initial uptake over the first 10 minutes, reaching a concentration maxima after 30 minutes.Overall, the study reveals that many published studies may be incorrect as they may only be reporting the presence of a fluorescent dye inside the cell not the peptide. The fast binding of the peptide to the membrane is likely to cause false positive results when traditionally studying internalisation kinetics such as using flow cytometry and confocal microscopy. Correlation spectroscopy techniques such as FCS, provide useful information on internalisation of the peptides, but the single spot measurement is limited when providing information on the entire cell. RICS is a progression of correlation spectroscopy and provides a more representative picture of the cell.
6

A 2 1/2 dimensional thermohaline circulation model with boundary mixing / Two and one-half dimensional thermohaline circulation model with boundary mixing

Ru, Hua January 2000 (has links)
Thesis (S.M.)--Joint Program in Physical Oceanography (Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences and the Woods Hole Oceanographic Institution), 2000. / Includes bibliographical references (leaves 78-82). / A simple quasi-two dimensional dynamical model of Thermohaline circulation (THC) is developed, assuming that the mixing only occurs near western and eastern boundary layers. When the surface density is prescribed, the climatically important quantities, such as the strength of overturning and meridional heat transport, are related to the zonal integral over the vigorously mixing regions and scaled as (KvΔx)2/3. The numerical results suggest that the density difference between eastern and western boundaries play an important role in the meridional overturning. The eastern boundary is characterized by the upwelling on top of downwelling. The western boundary layer is featured by the universal upwelling. The inefficiency of diffusion heat transport accounts for the narrowness of sinking region and shallowness of overturning cell in one-hemisphere. The experiments with other surface boundary conditions are also explored. The circulation patterns obtained are similar under various surface temperature distributions, suggesting these are very robust features of THC. The role of boundary mixing is further explored in global ocean. The 2 1/2 dynamical model is extended to two-hemisphere ocean. Additional dynamics such as Rayleigh friction and abyssal water properties are taken into account. A set of complicated governing equations are derived and numerically solved to obtain steady state solution. The basic circulation features are revealed in our dynamical model. An equtorially asymmetric meridional circulation is observed due to small perturbation at the surface temperature in the high latitude. The density differences between eastern and western boundaries are distinct in both hemispheres. This is achieved during the spin-up process. Although the dynamical model results agree well with OGCM results in one-hemisphere, several important dynamics are lacking and exposed in two-hemisphere experiments. We need to consider horizontal advection terms which will effectively advect positive density anomalies across the equator and form the deep water for the entire system. / by Hua Ru. / S.M.
7

Utilizing an efficient color-conversion layer for realization of a white light-emitting electrochemical cell

Vedin, Joel January 2016 (has links)
Organic semiconducting materials have received a lot of attention in recent years and can now be found in many applications. One of the applications, the light emitting electrochemical cell (LEC) has emerged due to its flat and lightweight device structure, low operating voltage, and possibility to be fully solution processed. Today LECs can emit light of various colors, but to be applicable in the lighting industry, white light need to be produced in an efficient way. White light on the other hand, is one of the toughest "colors" to achieve in an efficient way, and is of particular interest in general lighting applications, where high color-rendering index devices are necessary. In this thesis I show that blue light can be partially converted, into white light, by utilizing the photoluminescence of color conversion layers (CCLs). Furthermore, I show that a high color-quality white light can be attained by adopting a blue-emitting LEC with a CCL. Particularly, three different color-conversion materials were embedded onto a blue bottom-emitting LEC, to study the resulting spectrum. One of the materials, MEH-PPV, have good absorption compatibility with the electroluminescence of the blue emitters, but the materials photoluminescence do not cover the red to deep-red range of the spectrum. These parts of the spectrum are necessary to obtain high color rendering indices (≥80). A single layer of MEH-PPV adapted onto a blue-emitting LEC, led to a cold white LEC with CIE-coordinates x = 0.29, and y = 0.36, color-rendering index = 71, and correlated color temperature = 7200 K. These properties makes it potentially useful in outdoor-lighting applications. The photoluminescence of another studied color-converting material, polymer red, covers the red to deep-red range of the spectrum but the material lacks absorption in the green parts of the blue emitters electroluminescence spectrum. Thus it is necessary to combine it with MEH-PPV to be able to absorb all wavelengths from the blue-emitter and get a broad light-spectrum out of the device. In order to preserve a part of the blue light, a new device configuration was designed. It features a top-emitting blue LEC with a dual-layer CCL which reach an impressive color rendering index = 89 at a correlated color temperature = 6400 K (CIE-coordinates x = 0.31, y = 0.33). The color-rendering index is the highest reported for a white LEC. The absence of UV-, and IR-radiation, together with the high color rendering properties make the white LEC a possible candidate for even the most demanding lighting-applications, such as art galleries, and shop display windows, together with indoor lighting. In this thesis, I show that the CCLs function well. However, for the LECs to be worthy competitors, the efficiency and lifetime of the blue emitter need improvements.

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