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The purpose of this project was to assess techniques which could be implemented in clinical cardiac MRI using a moderate gradient performance imaging system in order to aid in the assessment of myocardial function. Possible improvements in image contrast were assessed using four different magnetisation preparation schemes applied prior to MR image acquisition in order to aid in the delineation of myocardial borders, and therefore improve cardiac image assessment quality. The usefulness of several novel T2*-weighted acquisition techniques were assessed in clinical cardiac applications in order to indirectly assess myocardial perfusion. Four magnetisation preparation schemes were applied in order to attempt to improve image contrast in short axis gradient-echo cardiac MRI; T2, T1, Magnetisation Transfer Contrast (MTC), and Double Inversion (DI). The T2, and preparation schemes proved to be the most effective, showing an initial improvement in image contrast by approximately 100% and proving effective in improving image contrast over the entire imaging duration {550 ms through the cardiac cycle). The MTC preparation scheme showed a 50% improvement in image contrast, again being effective over the entire imaging duration. The DI preparation scheme proved useful in creating a black blood gradient-echo image but showed no improvement in contrast throughout the imaging duration (since the DI preparation technique is essentially a 'snapshot' technique). Recent developments in cardiac MRI have moved towards assessment of myocardial perfusion, using first-pass contrast-enhancement imaging. This approach requires assessment of a large enough volume of the heart to allow assessment of perfusion as well as retaining a high temporal resolution of 7 or 2 seconds, and therefore a more modem high performance imaging system. For moderate performance gradient MR systems an alternative method of assessing myocardial perfusion is therefore required. Several novel techniques to assess myocardial T2* values in order to indirectly infer myocardial perfusion are introduced. The use of an original multi-echo gradient-echo imaging sequence to acquire T2* pixel-maps was investigated in phantoms and compared with commercially available sequences in order to validate its use.

This thesis sets out to examine the relationship between macro economic policies in Chile and their consequences at the micro (local) level. The time period under examination covers the 1973-90 military dictatorship period, the 1990-93 transitional government of Patricio Aylwin and the current Christian Democratic government of Eduardo Frei. The research carried out between 1990 and 1997 looks at three case studies from distinct sectors with the objective of examining micro economic changes which occurred under each set of macro policies. First of all a study of the forestry sector examines how natural resources were affected by the pure neo-liberal economic model adopted by the military government. Secondly, a study of apple juice production in the IX region analyses the socio-economic consequences of attempts to integrate small producers into the agro-industrial chain as a result of the economic policy changes undertaken during Chile's first transitional period. Thirdly, a participatory project in the Concepcion metropolitan area is examined, to see to what extent the Frei government has been successful in achieving its aims of decentralising planning functions and incorporating local people into the decision making process. The central hypothesis of the study is that there is a direct link between macro economic policy and micro effects, and that the free market neo-liberal model in its pure form is incapable of meeting the challenge of sustainable development. We conclude that rather than merely modifying the existing free market model, with punitive social and environmental measures, a structural transformation may be necessary. A fundamental prerequisite for this change based on case study experience would appear to be the successful incorporation of local knowledge and experiences into the planning process.