Search

This thesis represents an investigation of composition and performance processes from gamelan music (particularly the traditional form karawitan), and the potential for their application in the medium of electroacoustic music. The research was developed through a mixture of theory and practice in a feedback relationship; the written thesis accompanies a portfolio of compositions and arrangements of traditional pieces, alongside software developed in Max/MSP to emulate and expand upon selected aspects of gamelan performance practice. The thesis is divided into two parts. Part I establishes the theoretical foundations for the thesis, introducing key concepts from ethnomusicology, gamelan music, and theory developed for electroacoustic music. Central to the thesis is a notion of “idiom” involving constraints, affordances, and individual expression. While the choice of instruments does not always influence musical style, karawitan presents examples of established instrumental roles in relation to a central framework. In the absence of a unified electroacoustic theory, Schaeffer’s musique concrète provides a starting point for discussion. Further ideas are developed using an adaptation of Simon Emmerson’s language grid (1986) to identify situations in which musical information is imposed from elsewhere, developed directly from the sound materials, or a combination thereof. This leads to the proposal of a set of strategies for composition and analysis of new works. Three areas are discussed through a set of case studies: the development of syntax and idiomatic discourse, idiomatic references and their interpretation, and the use of cues to establish discourse. Part II examines the compositions developed during the research. A description of the overall composition framework and technical considerations is presented, in which abstract algorithmic-oriented approaches are compared with a more concrete approach to sound. A general commentary leads into the description and analysis of works in the portfolio based on the methods exposed in the body of the thesis.

Molecular dynamics (MD) computations aim to simulate materials at the atomic level by approximating molecular interactions classically, relying on the Born-Oppenheimer approximation and semi-empirical potential energy functions as an alternative to solving the difficult time-dependent Schrodinger equation. An approximate solution is obtained by discretization in time, with an appropriate algorithm used to advance the state of the system between successive timesteps. Modern MD simulations simulate complex systems with as many as a trillion individual atoms in three spatial dimensions. Many applications use MD to compute ensemble averages of molecular systems at constant temperature. Langevin dynamics approximates the effects of weakly coupling an external energy reservoir to a system of interest, by adding the stochastic Ornstein-Uhlenbeck process to the system momenta, where the resulting trajectories are ergodic with respect to the canonical (Boltzmann-Gibbs) distribution. By solving the resulting stochastic differential equations (SDEs), we can compute trajectories that sample the accessible states of a system at a constant temperature by evolving the dynamics in time. The complexity of the classical potential energy function requires the use of efficient discretization schemes to evolve the dynamics. In this thesis we provide a systematic evaluation of splitting-based methods for the integration of Langevin dynamics. We focus on the weak properties of methods for confiurational sampling in MD, given as the accuracy of averages computed via numerical discretization. Our emphasis is on the application of discretization algorithms to high performance computing (HPC) simulations of a wide variety of phenomena, where configurational sampling is the goal. Our first contribution is to give a framework for the analysis of stochastic splitting methods in the spirit of backward error analysis, which provides, in certain cases, explicit formulae required to correct the errors in observed averages. A second contribution of this thesis is the investigation of the performance of schemes in the overdamped limit of Langevin dynamics (Brownian or Smoluchowski dynamics), showing the inconsistency of some numerical schemes in this limit. A new method is given that is second-order accurate (in law) but requires only one force evaluation per timestep. Finally we compare the performance of our derived schemes against those in common use in MD codes, by comparing the observed errors introduced by each algorithm when sampling a solvated alanine dipeptide molecule, based on our implementation of the schemes in state-of-the-art molecular simulation software. One scheme is found to give exceptional results for the computed averages of functions purely of position.

Antitumour quinols containing the 4-hydroxycyclohexa-2,5-dienone pharmacophore potently inhibit human tumour cell growth in vitro and in vivo. This activity is postulated to occur via inhibition of the thioredoxin/thioredoxin reductase (TrxlTrxR) redox system which reduces numerous substrates involved in cellular proliferation, signal transduction, redox homeostasis and apoptosis. Similar to the archetypal quinol, PMX 464, its eventual successor, PMX 290, induced caspase-dependent apoptosis, cell cycle arrest and oxidative stress in sensitive tumour cells whilst depletion of glutathione increased tumour cell sensitivity to PMX 290. The ability of PMX 464 and PMX 290 to induce cellular responses understood to occur downstream of TrxlTrxR inhibition that could account for their antitumour activity were investigated. Quinol activity was shown to be independent of oxidative stress. Colon cancer cells stably overexpressing catalase retained sensitivity to PMX 464 and PMX 290 yet were resistant to hydrogen peroxide whilst the use of radical scavengers failed to abrogate quinol activity. Trx binds to and inhibits apoptosis signalling kinase 1 (ASK1), a mitogen activated protein kinase (MAPK) kinase kinase responsible for stress-induced apoptosis via sustained activation of the MAPKs c-jun N-terminal kinase (JNK) and p38. PMX 464 and PMX 290 disrupted cellular ASK1 :Trx1 complexes and induced sustained JNKlp38 phosphorylation yet overexpression of dominant negative ASK1 or pharmacological inhibition of JNKlp38 did not prevent quinol-induced apoptosis. Additionally, knockdown of Trx1 using siRNA did not impact quinol activity suggesting additional mechanisms of action. PMX 290 induced endoplasmic reticulum (ER) stress at apoptosis-inducing concentrations below those required to inhibit cellular TrxlTrxR. Upregulation of ER stress proteins, translation-inactivating phosphorylation events and ER distension occurred in response to PMX 290 alongside the accumulation/aggregation of ubiquitinated proteins prior to the onset of apoptosis. Proteasome inhibition was not responsible for these effects. A definitive cellular target for PMX 290 was not identified, however, useful tools have been generated which could be applied to investigate the actions of other redox homeostasis modulating therapies.

This thesis investigates the interaction between the evolution of the Irish Question and the re-emergence of Britain's two-party political system after World War I. It challenges the contention summed up in A.J.P. Taylor's suggestion that David Lloyd George 'conjured' the Irish Question out of existence with the Anglo-Irish Treaty of 1921. Here, it is shown that on the contrary the Irish dispute continued to be a highly sensitive issue for successive British governments until the Treaty's Boundary Commission report was shelved in 1925. This was so because British politics was then undergoing a profound revolution. Its climax was the 1924 general election, which established the Conservatives as the dominant players in British politics, ensured Labour's place as the leading party of the left, and confirmed the eclipse of Liberalism. The first of this study's two aims is to set the Irish dispute within this wider context. Specifically, it examines how the answer to the Irish Question that was devised by Lloyd George and his Coalition partners was constructed and then dismantled as a result of this revolution. The second aim of this thesis is to demonstrate that the Boundary Commission was only one element in the Treaty's Ulster clauses, all of which were designed to bring about Ireland's re-unification. The intent was to exploit the financial restrictions of the 1920 Government of Ireland Act and thus pressure Ulster Unionists into joining a single Irish Parliament. This aspect has been overlooked in other studies, though it posed as serious a threat to Northern Ireland's survival as the Commission itself.

The story of the early years of the Permanent University Fund has been told many times. However, this dissertation attempts to tell the story using as primary source documents the minutes of the University of Texas Board of Regents meetings. In doing the research, it soon became apparent that the Regents minutes would give an incomplete story line, so a more historical research approach was used. Early Texas leaders had an interest in higher education from the beginning of the Republic of Texas. It is interesting to note that this occurred at a time when there was very little in the way of formal public elementary or secondary schools in the state. Nevertheless, the early legislatures put into place a series of laws that laid a very good foundation for Texas higher education. The establishment of the PUF and the efforts of early Regents to manage this asset correctly is one of the great stories of the state. The Regents began managing a large number of acres of land that had little value except as grazing land. The value of the property was low, and the income derived from the land was modest. Later, with the discovery of oil on these lands, there was and continues to be great wealth generated. The increase in wealth that came primarily from oil leases caused a number of interesting disagreements. The long-running dispute between the University of Texas and Texas A&M College is researched until 1937 when the A&M Board decided to stop pursuing the financial and legal issues. Because of the wealth and the activity that occurred on the PUF land, there was a long-running dispute between the Regents and the Commissioner of the General Land Office that is important to the story of the PUF. The impact the Bureau of Economic Geology had on the PUF is closely documented and seems to prove the importance of well-educated geologists on the successful discovery and production of oil on the PUF land. It has been said that this story of the University of Texas and the Permanent University Fund is really a story about Texas, because it involves land, oil and education. The impact of the PUF on higher education in Texas has been enormous.