How does Johann Sebastian Bach vary his approach to fugal composition in his organ works? : A study of fourteen strategically selected organ fugues.

The thesis commences with an introduction examining the external influences and the work ethic of J.S. Bach. The first aim, albeit subsidiary to the subsequent aim, is to magnify and raise the issues concerning the lacuna of fugal analytical methodology and the underwhelming quality of analytical literature on the J.S. Bach organ works. As such, the misconception of fugal terminology, the lax analytical interpretations and the lack of cogent and compelling analytical accounts are all addressed. The second aim which is integral to each analytical account of the fourteen fugues is to elucidate the contrapuntal paradigms and matrices contained therein. As of yet, attempts have not been made to provide rational schematic tables which illustrate the subject and countersubject(s) entries. Indeed, it is then of profound importance to examine each of these fourteen fugues and distil precisely the compositional procedures and mechanisms they possess. The fourteen fugues have not been selected without reasoning; they have also been selected to reveal a likely chronology. Fundamentally, they each reveal a vast spectrum of compositional traits, origins and hallmarks that are unique to each. The overarching purpose is thus to provide an enlightened comprehension as to the compositional procedures that define the essence of each fugue. Despite the fervour for J.S. Bach as a composer of outstanding calibre and how highly regarded the organ works are held, it is surprising that for in excess of two hundred and fifty years, the compositional procedures and structural designs of his organ works have yet to be fully understood. Whilst this thesis does not aim to provide an in - depth analytical account of each bar within each fugue, it nonetheless seeks to provide a cohesive account for the fourteen fugues and above all to reinforce that fugue is a radically varying compositional style

Epitaxial growth and surface reconstruction of CrSb(0001)

Smooth CrSb(0001) films have been grown by molecular beam epitaxy on MnSb(0001) – GaAs(111) substrates. CrSb(0001) shows (2 × 2), triple domain (1 × 4) and (√3×√3)R30° reconstructed surfaces as well as a (1 × 1) phase. The dependence of reconstruction on substrate temperature and incident fluxes is very similar to MnSb(0001)

HARDI: A high angular resolution deployable interferometer for space

We describe here a proposed orbiting interferometer covering the UV, visible, and near-IR spectral ranges. With a 6-m baseline and a collecting area equivalent to about a 1.4 m diameter full aperture, this instrument will offer significant improvements in resolution over the Hubble Space Telescope, and complement the new generation of ground-based interferometers with much better limiting magnitude and spectral coverage. On the other hand, it has been designed as a considerably less ambitious project (one launch) than other current proposals. We believe that this concept is feasible given current technological capabilities, yet would serve to prove the concepts necessary for the much larger systems that must eventually be flown. The interferometer is of the Fizeau type. It therefore has a much larger field (for guiding) better UV throughout (only 4 surfaces) than phased arrays. Optimize aperture configurations and ideas for the cophasing and coalignment system are presented. The interferometer would be placed in a geosynchronous or sunsynchronous orbit to minimize thermal and mechanical disturbances and to maximize observing efficiency

Hydrology of the Forest City Basin, mid-continent, USA : implications for CO2 sequestration in the St. Peter sandstone

Title from PDF of title page (University of Missouri--Columbia, viewed on March 6, 2013).The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Thesis advisor: Dr. Martin AppoldIncludes bibliographical references.M.S. University of Missouri--Columbia 2012."December 2012"The purpose of this research was to perform a preliminary assessment of the stratigraphy, storage capacity, hydrology and mineraology of this basin to determine its suitability and structural trapping capacity for geologic sequestration of carbon dioxide. The basin is stratigraphically suited in that it contains the St. Peter Sandstone, a high permeability aquifer which is overlain by multiple low permeability units. These should act as a seal to prevent the upward migration of injected CO2. Construction of a three dimensional stratigraphic model produces storage capacity estimates within the St. Peter ranging from 5.2 to 830 megatonnes CO2. Groundwater modeling results highlight potential areas of flow stagnation and a predominately lateral flow regime within the St. Peter Sandstone. This, coupled with relatively low flow velocities in most model scenarios, indicates that CO2 as a dissolved phase in groundwater is not likely to escape the basin through lateral migration in less than 1,000 years, the commonly accepted performance standard for sequestration (Hepple and Benson, 2005). Mineralogical analysis also indicates a grain matrix composed almost entirely of quartz which is non-reactive with CO2; this indicates that dissolution of the grain matrix upon injection is not likely to occur and result in any loss of conductivity or porosity through grain collapse. The preliminary results presented in this study indicate that the Forest City Basin is indeed suitable for carbon sequestration and warrants further investigation

Growth and characterisation of MnSb thin films and interfaces

The deposition of Mn on to reconstructed InSb and GaAs surfaces has been studied by re ection high-energy electron diffraction (RHEED), atomic force microscopy and scanning tunnelling microscopy. On both Ga- and As-terminated GaAs(001), a Mn-induced (2x2) reconstruction is observed. In contrast, there are no well defined Mn-induced surface reconstructions on InSb. Islands are observed to form on all of the surfaces studied, with islands on the Group III-rich surfaces composed of elemental Mn and of an alloy on the Group V-rich surfaces. The conversion from Group III(V)-rich to Group V(III)-rich surfaces are discussed in terms of basic thermodynamic quantities and a number of models for surface atom substitution are proposed as pathways for MnAs and MnSb island formation. A high resolution X-ray diffraction study (HRXRD) has been performed on niccolite, cubic and wurtzite crystallites present within MnSb thin films grown on GaAs(111) substrates. It is observed that the lattice parameters of the polymorphs do not depend on the film thickness or the time-corrected beam ux ratio, J. The niccolite phase is found to relax rapidly (within 3 nm) and the average c lattice parameter of these films is 5.791(1) A. Variations in the c lattice parameter indicate that the average stoichiometry of the films varies on a per sample basis and this may act to promote the formation of polymorphs. Cubic MnSb crystallites exhibit a large strain dispersion of approximately 1 % and a rhombohedral or trigonal distortion is believed to be the origin. Quantitative analysis of asymmetric reciprocal space maps reveals that films grown using the optimised conditions have the highest concentration of the cubic polymorph, with lower values of J in the optimised range promoting this polymorph. The growth of MnSb on Ge(001) and Ge(111) substrates has been investigated. On Ge(001) growth proceeds through the formation of three dimensional islands and no dependence on the growth conditions is observed. Evidence for (1102) and (1120) crystallites is seen in XRD and RHEED, respectively. The interface between the MnSb islands and the Ge(001) substrate is sharp with no evidence for interfacial reactivity. The epitaxial growth of MnSb on Ge(111) is reported for the first time. The growth orientation is confirmed to be (0001) by X-ray diffraction while the layers are found to be ferromagnetic with a Curie temperature in excess of 300 K

Stability of a Spherical Accretion Shock with Nuclear Dissociation

We examine the stability of a standing shock wave within a spherical accretion flow onto a gravitating star, in the context of core-collapse supernova explosions. Our focus is on the effect of nuclear dissociation below the shock on the linear growth, and non-linear saturation, of non-radial oscillations of the shocked fluid. We combine two-dimensional, time-dependent hydrodynamic simulations using FLASH2.5 with a solution to the linear eigenvalue problem, and demonstrate the consistency of the two approaches. Previous studies of this `Standing Accretion Shock Instability' (SASI) have focused either on zero-energy accretion flows without nuclear dissociation, or made use of a detailed finite-temperature nuclear equation of state and included strong neutrino heating. Our main goal in this and subsequent papers is to introduce equations of state of increasing complexity, in order to isolate the various competing effects. In this work we employ an ideal gas equation of state with a constant rate of nuclear dissociation below the shock, and do not include neutrino heating. We find that a negative Bernoulli parameter below the shock significantly lowers the real frequency, growth rate, and saturation amplitude of the SASI. A decrease in the adiabatic index has similar effects. The non-linear development of the instability is characterized by an expansion of the shock driven by turbulent kinetic energy at nearly constant internal energy. Our results also provide further insight into the instability mechanism: the rate of growth of a particular mode is fastest when the radial advection time from the shock to the accretor overlaps with the period of a standing lateral sound wave. The fastest-growing mode can therefore be modified by nuclear dissociation.Comment: Version accepted by ApJ. Consistent parameter range, and additional plots with eigenfrequencies in units of inverse postshock advection timescale. Minor changes otherwis

Plasmonic resonances of metallic nanoparticles in arrays and in isolation

Plasmonics is the branch of photonics that is concerned with the interactions which take place between metallic structures and incident electromagnetic radiation. It is a field which has seen a recent resurgence of interest, predominantly due to the emerging fields of metamaterials and sub-wavelength optics. The original work contained within this thesis is concerned with the plasmonic resonances of metallic nanoparticles which can be excited with visible light. These structures have been placed in a variety of configurations, and the optical response of each of these configurations has been probed both experimentally, and with numerical simulations. The first chapter contains some background and describes some recent advances in the literature, set against the broad background of more general concepts which are important in plasmonics. The best starting point in describing the response of plasmonic systems is to consider individual metallic particles and this is the subject of the second chapter. Three separate modelling techniques are described and compared, and dark-field spectroscopy is used to produce experimental scattering spectra of single particles which support dipolar and higher order modes. Mie theory is used as a starting point in understanding these modes, and finite element method (FEM) modelling is used to make numerical comparisons with dark-field data. When two plasmonic particles are placed close to each other, interactions take place between them and their response is modified, sometimes considerably. This effect can be even stronger if particles are placed in large arrays. Interactions between the dipolar modes of gold particles form the basis of the third chapter. The discussion begins with pairs of particles, and the coupled dipole approximation (CDA) is introduced to describe the response. Ordered square arrays are considered and different modelling techniques are compared to experimental data. Also, random arrays have been investigated with a view to inferring the extinction spectrum of a single particle from a carefully chosen array of particles in which the inter-particle interactions are suppressed. The fourth chapter continues the theme of particles interacting in arrays, but the particles considered support quadrupolar modes (and they are silver instead of gold). The optical response is strongly modified, and an explanation is provided which overturns the accepted explanation. The final chapter of new results is somewhat different to the others in that a very different structure is considered and different parameters are extracted. Instead of far-field quantities, here, near-fields of composite structures are of interest; they can generate greatly enhanced fields in the vicinity of the structure. These enhanced fields, in turn, enhance the fluorescence and Raman emission of nearby dye molecules. A novel field integration technique is proposed which aims to mimic the experiments which were carried out using fluorescence confocal microscopy.GWR / Qineti

The Physical Effects of Progenitor Rotation: Comparing Two Long-Duration 3D Core-Collapse Supernova Simulations

We analyse and determine the effects of modest progenitor rotation in the context of core-collapse supernovae by comparing two separate long-duration three-dimensional simulations of 9 M$_{\odot}$ progenitors, one rotating with an initial spin period of $\sim$60 seconds and the other non-rotating. We determine that both models explode early, though the rotating model explodes a bit earlier. Despite this difference, the asymptotic explosion energies ($\sim$10$^{50}$ ergs) and residual neutron star baryon masses ($\sim$1.3 M$_{\odot}$) are similar. We find that the proto-neutron star (PNS) core can deleptonize and cool significantly more quickly. Soon into the evolution of the rotating model, we witness more vigorous and extended PNS core convection that early in its evolution envelopes the entire inner sphere, not just a shell. Moreover, we see a corresponding excursion in both the $\nu_e$ luminosity and gravitational-wave strain that may be diagnostic of this observed dramatic phenomenon. In addition, after bounce the innermost region of the rotating model seems to execute meridional circulation. The rotationally-induced growth of the convective PNS region may facilitate the growth of core B-fields by the dynamo mechanism by facilitating the achievement of the critical Rossby number condition for substantial growth of a dipole field, obviating the need for rapid rotation rates to create dipole fields of significance. The next step is to explore the progenitor-mass and spin dependencies across the progenitor continuum of the supernova explosion, dynamics, and evolution of PNS convection and its potential role in the generation of magnetar and pulsar magnetic fields.Comment: Withdrawn pending further calculation

The DUB/USP17 deubiquitinating enzymes: A gene family within a tandemly repeated sequence, is also embedded within the copy number variable Beta-defensin cluster

<p>Abstract</p> <p>Background</p> <p>The DUB/USP17 subfamily of deubiquitinating enzymes were originally identified as immediate early genes induced in response to cytokine stimulation in mice (DUB-1, DUB-1A, DUB-2, DUB-2A). Subsequently we have identified a number of human family members and shown that one of these (DUB-3) is also cytokine inducible. We originally showed that constitutive expression of DUB-3 can block cell proliferation and more recently we have demonstrated that this is due to its regulation of the ubiquitination and activity of the 'CAAX' box protease RCE1.</p> <p>Results</p> <p>Here we demonstrate that the human DUB/USP17 family members are found on both chromosome 4p16.1, within a block of tandem repeats, and on chromosome 8p23.1, embedded within the copy number variable beta-defensin cluster. In addition, we show that the multiple genes observed in humans and other distantly related mammals have arisen due to the independent expansion of an ancestral sequence within each species. However, it is also apparent when sequences from humans and the more closely related chimpanzee are compared, that duplication events have taken place prior to these species separating.</p> <p>Conclusions</p> <p>The observation that the DUB/USP17 genes, which can influence cell growth and survival, have evolved from an unstable ancestral sequence which has undergone multiple and varied duplications in the species examined marks this as a unique family. In addition, their presence within the beta-defensin repeat raises the question whether they may contribute to the influence of this repeat on immune related conditions.</p