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The investigations reported here address the issue of overcoming loss in a typical isotropic metamaterial. The possibility of adding functionality to such materials, through gyrotropic effects, and diffraction management of nonlinear beams, driven by negative phase accumulation, is presented. Loss is overcome by the introduction of gain to the metamaterial. This is achieved on the basis that typical split-ring metaparticles can be suitably enhanced through the addition of carefully selected diodes. The detailed analysis given here deploys a familiar equivalent circuit model and specific current-voltage characteristics. It is emphasised that conditions must be in place to ensure overall stable material behaviour. The methodology uses convective and absolute instability concepts and it is shown that the latter can be so detrimental as to lead to a much reduced frequency window of operation. Another set of investigations emphasises that surface waves provide a path to new science. Consequently the propagation of surface waves along the interface between a metamaterial and a gyrotropic medium is promising for applications. The investigation outcomes of this complicated system need to demonstrate generation properties in real time. Hence, some unique finite-difference time-domain (FDTD) computations have been developed enabling their interesting connection to the Goos- Hanchen shift to be elegantly displayed. Many interesting forms of surface waves are discussed including the simultaneous generation of TE and TM waves propagating in opposite directions. It is well known that in an isotropic metamaterial backward waves can exist so this property is exploited to create a fascinating form of diffraction management. This is investigated both for the bulk and for cavities and the impact of what is defined as nonlinear diffraction is introduced. Finally, some magnetooptics is introduced that adds even more functionality to the generation of cavity solitons.

The aim of this study is to examine the influence of local sport interests in one English city in mediating national sport policy initiatives in education, land-use planning and health. This is attempted through an analysis of relationships between key policy actors and the strategies adopted to pursue and defend policy priorities, set within an historical, institutional, political and socio-economic context. Given the increasing political salience of sport, the rationale for the study is to understand the consequences for local sport interests of the re-structuring of the policy area over the last decade. The study is grounded in the ontological and epistemological assumptions of critical realism and its attendant understanding of the dialectical relationship between structure and agency. A neo-pluralist theory of the state and power is adopted in order to provide a macro-level context to the three meso-level theoretical approaches utilised in this study for analysing policy processes, namely: policy networks, the multiple streams framework (MSF) and the advocacy coalition framework (ACF). This approach to examining sport policy processes is complemented by insights from the literature on local government and governance, given that the primary empirical focus is on Liverpool City Council. The empirical work consists of an investigation of first, city council sport policy from the 1970s to date and particularly the period 1995–2006, and second, three aspects of local sport policy that relate to national sport policy, namely: school sport, the playing fields issue, and sport's role in health policy. In terms of research methods, the study utilises a case study approach that included undertaking forty semi-structured interviews with personnel within the sport policy area at the local, county, regional and national levels; an analysis of policy-related documentation produced by central and local government; and observation in council meetings and forums. A discussion of the findings examines the utility of the theoretical frameworks drawn upon in explaining the findings of the study.