<p>University of Warwick institutional repository<a href="/goto?url=http://go.warwick.ac.uk/wrap" target="_blank">: </a><a href="/goto?url=http://go.warwick.ac.uk/wrap" target="_blank">http://go.warwick.ac.uk/wrap </a></p><p><strong>A Thesis Submitted for the Degree of PhD at the University of Warwick </strong></p><p><a href="/goto?url=http://go.warwick.ac.uk/wrap/67042" target="_blank">http://go.warwick.ac.uk/wrap/67046 </a></p><p>This thesis is made available online and is protected by original copyright. Please scroll down to view the document itself. Please refer to the repository record for this item for information to help you to cite it. Our policy information is available from the repository home page. </p>