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My research has focused on the effects of reflective surfaces such as metals and dielectric stacks on the light emission from conjugated polymers. Conjugated polymers have semiconducting properties which arise from the delocalisation of electrons along the polymer backbone. These plastics are efficient light-emitters both in photoluminscence (PL) and Electroluminescence (EL). One of the unique features of these materials is their broad emission spectrum. Proximity to reflective surfaces alters the radiative rate of an emitter because of interference effects. This modification to the radiative rate is a function of the dielectric properties of the mirror, the orientation of the dipole, the distance between the dipole and the mirror, the emission angle, and the emission wavelength. In addition, non-radiative energy transfer from the emitter to excitations in a metal film efficiently quench luminescence at separations less than 60 nm. I have investigated the effects of interference and non-radiative energy transfer on the emission spectra and the PL and EL quantum efficiencies of conjugated polymer structures. The PL from thin films of conjugated polymers spin-coated onto Al and Au films, with and without SiO₂ spacer layers in between, was investigated. PL was found to be quenched close to the metal films. Experiments on double-layer LEDs where the distance between the emissive region can be controlled by altering the film thicknesses of the polymer layers extended those results from PL to EL. In addition, changes in the PL spectra and PL efficiency with increasing polymer-metal separation could be explained by computer-modelling the radiative power of oscillating dipoles. The results allowed design rules to be formulated which could improve the efficiency of LEDs, photovoltaic cells and microcavity devices in which the polymer film is sandwiched between two mirrors. Comparison between experiment and modelling revealed some information about the photophysics of conjugated polymers. Microcavities (Fabry-Perot resonators containing a light-emitter) modify the radiative rate of an emitter more strongly than single mirror devices. I have investigated the role of the dielectric properties of metals on the resonance wavelengths of a microcavity. It is shown that the metal film thickness influences the cavity resonances and that the angular dependence of the microcavity emission can be reduced exploiting specific properties of the metal.

AIM - To explore the perspectives of service users and professional staff towards service user involvement within the context of a changing cultural environment at a UK hospice. METHOD - Case study and thematic analysis including interviews with 16 staff including the CEO and 6 service users at a UK hospice. FINDINGS - Three overarching themes were identified: involvement and disempowerment in decision-making; belonging and alienation in a period of organisational change; struggle to maintain wellbeing and identity in a changing culture. A key finding is that service users receiving care from the hospice wanted their voices to be heard, valued and respected for their personal care and issues affecting the hospice. Service users did not consider it a burden to be asked for their views. They felt disempowered by a consultation process about organisational changes that appeared not to take their views on board. There is a need to consider whether a reliance on surveys for involving service users is sufficient or can become tokenistic. External social-political-economic pressures plus increasing privatisation of public services could influence the way that hospices operate in future. This could involve moving from a sanctuary to a business culture and potentially towards managerialism by adopting a regulatory rather than rights-based approach with an emphasis on increasing reach, measuring numbers and hitting targets. Service users being viewed as consumers with a focus on reablement/rehabilitation activities and less on psychosocial support could also serve to push hospices to start behaving more like hospitals. CONCLUSION - More qualitative research is needed to ensure the voices of service users living with a life-limiting illness are heard. The contributions they make towards co-production of services and research should also be heard and influence practice and policy. Service users should also be more involved in education and training of staff.

Motivational Interviewing (MI) has been shown to be an effective treatment for substance abuse and other lifestyle and/or behavioural problems. However, mechanisms of change remain a topic of speculation. It has been hypothesised that MI works by eliciting and resolving a client's ambivalence, thereby enhancing their motivation and commitment to change. Research has supported the theory that enhancing commitment is an integral element of MI, however little is known about the role ambivalence plays in producing change. The aim of this project was to investigate this role, and the possible role of other relevant models from social psychology such as cognitive dissonance. First, the social psychology literature relating to the process of ambivalence and dissonance was reviewed to determine whether this was adequately reflected in the literature on MI. It was found that a comprehensive, contemporary view of these processes is largely absent from the literature on MI, and that this may be potentially valuable in furthering an understanding of the mechanisms of change. Second, a secondary analysis of data from a completed randomized controlled study (the United Kingdom Alcohol Treatment Trial - UKATT) on the effectiveness of Motivational Enhancement Therapy (MET), an adaptation of MI, was carried out. This used a thematic analysis with an a priori coding frame based upon constructs shown previously by research in social psychology to be important in ambivalence and dissonance. The aim was to explore the relevance of these constructs to understanding the processes within sessions of MI, and to determine whether either the model of ambivalence or cognitive dissonance offers an advantage in analysing the data. Application of the a priori coding frame developed, to MET transcripts revealed variations in the expression of ambivalence and cognitive dissonance in client language. Inconsistencies both within and between the different cognitive components outlined in both theories occurred in close proximity to one another, inferring an experience of inconsistent related discomfort within the client. The thematic analysis also enabled the identification of additional themes, relevant to both ambivalence and cognitive dissonance theories, in client language. In total fourteen themes were identified, five ambivalence and nine cognitive dissonance. Ambivalence themes were expressed on 107 occasions and cognitive dissonance on 205. Ambivalence and cognitive dissonance theories prove to be valuable in examining and interpreting client language, providing a discrepancy-related model to enhance understanding of MI's motivational processes. It is concluded that cognitive dissonance more adequately captures the motivational processes reflected in client language: however ambivalence theory provides a more specific model, guiding clinicians and researchers delivering and investigating the elicitation and resolve of the ambivalent experience.