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Right ventricular (RV) size and function are prognostic in congenital and acquired heart disease. Two-dimensional echocardiography (2DE) is the most readily available modality for RV assessment, but is limited by its complex shape. Furthermore, biventricular function is intimately related through a shared septum and pericardium. The simplest metric of left ventricular (LV) function is ejection fraction (LVEF). However, LVEF is often maintained in pulmonary hypertension (PH), for example. Therefore better indicators of LV function are required to identify patients at risk of deterioration. In this thesis, novel imaging techniques for assessing cardiac function in right heart disease are investigated. The first experiment tested the hypothesis that single-beat threedimensional echocardiography (3DE) accurately and reproducibly quantifies RV volumes. 3DE traditionally acquires sub-volumes over consecutive heartbeats, whereas novel 3DE transducers can acquire datasets in a single cardiac cycle. Single-beat 3DE was compared against CMRI in 100 subjects including patients with PH and carcinoid heart disease. Single-beat 3DE was feasible and accurate for RV volumetric quantification, but with limitations of test-retest reproducibility. The second experiment tested the hypothesis that 2D knowledge-based reconstruction (2DKBR) accurately and reproducibly quantifies RV volumes. 2DKBR involves 2DE-acquired RV coordinates localized in 3D space and connected by reference to a disease-specific RV catalogue. This was validated against CMRI in 28 PH patients, and test-retest reproducibility was assessed. 2DKBR was feasible and accurate for RV volumetric quantification in PH, and more reproducible than conventional 2DE. The final experiment tested the hypothesis that multi-directional myocardial velocities could be assessed in PH by CMRI. A tissue phase mapping sequence was utilized in 40 PH patients and 20 healthy volunteers. Over a median follow-up period of 20 months, LV early diastolic wave velocities were the only independent predictors of functional capacity and clinical worsening in a model that includes conventional metrics of biventricular function.

This dissertation considers the history of the organs in Westminster Abbey and the music performed on them from the eleventh century to the start of the twentieth. It is primarily based on the documentary evidence in Westminster Abbey Library and Muniment Room and transcriptions of material from here form a large part of the appendices. The thesis considers the organs built especially for the Abbey and temporary instruments used for coronations and other events. The organ builders represented include John Howe, Thomas Dallam, John Burwood, Bernard Smith, Christopher Shrider, Thomas Elliot and William Hill. The organists of Westminster Abbey include the composers Edmund Hooper, Orlando Gibbons, John Blow, Henry Purcell, William Croft, Benjamin Cooke and James Turle. Compositions they wrote while in post are used as sources of information about the organ, and are related to the details of the instrument found in documentary and secondary sources. The compositions are used to evaluate these details when appropriate. A new edition of Benjamin Cooke's organ voluntaries and his Magnificat and Nunc Dimittis in G form part of the dissertation. The voluntaries appear together here for the first time in a modern edition. The choral repertoire is discussed with reference to part books used in the Abbey from the Restoration until the beginning of the twentieth century and to a catalogue of printed music in the choir library compiled around 1905. The role of the organ in the liturgical life of the Abbey is considered, and the political events which affected this are introduced and discussed. Coronation services take place in the Abbey. The music performed at these from Charles II to Victoria is established as far as possible from service books in Lambeth Palace Library and other sources. The musical forces available at coronations are discussed, including organs built in the Abbey especially for these events

The stability of wall driven and thermally driven cavity flow is investigated for a wide range of viscous and viscoelastic fluids. The effect of inertia, elasticity, temperature gradients, viscous heating and Biot boundary conditions are of particular interest. Both destabilisation and bifurcation phenomenon are found. For Newtonian constant viscosity flow the instabilities are characterised by a critical Reynolds number which represents the ratio of inertial forces to viscous forces, and instability occurs when the inertial forces become large. For non-Newtonian viscoelastic fluids the instability is characterised by a critical Weissenberg number, which represents the ratio of elastic forces to viscous forces, and instability also occurs when elastic forces dominate the viscous forces. For thermally driven flow the instability is characterised by a critical Rayleigh number, which represents the ratio of temperature gradient to viscosity, and instability occurs when the Rayleigh number become large. In this case the instability is also characterised by both Eckert and Biot number. The work has relevance to thermal convection and mixing processes which occur in the viscous and viscoelastic fluid within the Earth's mantle. Three-dimensional steady and transient flow in a cylindrical cavity and three dimensional steady flow in a spherical cavity, are also considered for both viscous and viscoelastic fluids. Instabilities in these three-dimensional flow depend on the same parameters as the flow in square cavity.

The work contained within this thesis is concerned with a theoretical investigatiop of both laminar and thermally driven types of cavity flow, together with an analysis of their associated mixing processes which find applications to Industrial mixing and also to the environment. The mixing efficiency has been viewed from two perspectives namely the tracking of a selection of fluid particles, and also the simulation of the dispersive mixing of a coloured fluid element as carried along by the flow. This thesis also incorporates features of both Newtonian and a wide range of non-Newtonian fluids.