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The F-μ-F state occurs when a spin polarised muon implanted in a fluoride crystal becomes entangled with its nearest neighbour fluorine nuclei, resulting in a beating pattern observed in the muon decay asymmetry. Ever since these states were discovered in the 1980s, they have never been fully understood, as fitting the data always required a phenomenological relaxation function to account for the observed decay of the oscillations. This thesis shows how this relaxation can be understood by considering it as a decohering process, achieved by taking into account the effect of all the nuclear spins beyond the nearest-neighbours. Starting with the simple cubic compounds CaF₂ and NaF, techniques are developed which allows one to calculate the way in which the quantum information of the muon gets irreversibly lost into the crystal. This thesis then expands on this to discuss the compounds PbF₂ and YF₃, which have a more complicated crystal structure, and in the former compound it is possible to identify Frenkel defects with μSR for the first time. This thesis then shows how it is possible to apply these techniques to magnets: starting with KPF₆ and KBF₄, which contain the [PF₆]− and [BF₄]− molecular ions which are often found in molecular magnets, it shows how the location of the muon site in the compound considerably changes the observed muon polarisation, determining the muon stopping site by carefully analysing the muon's environment. Finally, the antiferromagnetic material KAgF₃ is analysed with these methods, showing how a combination of DFT+μ, dipole field calculations and the techniques developed here can be used to determine the size of the electronic moments, confirm magnetic structures and narrow down the muon site. This final chapter also shows how the nearest-neighbour fluorine nuclear moment can affect the muon polarisation in magnets in a fascinating way.

Mass produced chemicals have revolutionised the way in which humans live and has led to both a significant increase in quality of life and a concomitant change in the way we pollute our habitats. Such chemicals include pharmaceuticals, plasticisers, perfluorinated compounds and metabolites which enter rivers via sources such as sewage treatment works (STW) effluent outfalls. The presence and distribution of these contaminants is of concern due to their increasing use and ability of some to biologically affect non-target aquatic organisms at trace (ng/L) levels. This work investigated the fate and distribution of selected pharmaceuticals, plasticisers, illict drugs, perfluorinated compunds (PFCs) and metabolites are investigated in three rivers of southern England. Specific objectives included establishing spatial distribution patterns of selected contaminants along the entire course of rivers receiving inputs from multiple STWs, their partition between bound (to suspended particulate material) and dissolved phases of river water, accumulation in sediment, bioaccumulation in primary producers including plants and biofilm/ periphyton, bioaccumulation in benthic aquatic organisms, adsorption of studied contaminants to polyethlene microparticles (similar to those used in cosmetic products) both in the lab and in rivers, and adsorption to 'natural' replacements for polyethylene microparticles (MPs). Spatial distribution analysis showed that selected contaminants are ubiquitous in the studied rivers with trace levels of plasticisers and perfluorinated compounds identified in river headwaters and beyond. Within the rivers studied in this work, pharmaceuticals were shown to be exclusively introduced by STW effluent and persisted exclusively in the dissolved phase of river water through the studies areas. Plasticisers and PFCs however were additionally introduced via runoff from streets, at times at higher concentrations than in SFWs effluent outfall and bound to suspended particulate material. Only PFCs and plasticisers were found to be bioaccumulative or very bioaccumulative in aquatic plants, biofilm. periphton and benthic organisms, and accumulated in sediment. Illicit drugs were only found in STW effluent and downstream river flow, almost exclusively in the dissolved phase of collected water. Laboratory assessment of adsorption to polyethylene MPs showed adsorption largely occurred via a linear isotherm and only for PFCs. However, trace levels of pharmaceuticals and an illicit drug urinary metabolite were extracted from polyethylene MPs deployed downstream from STW effluent outfalls in three rivers. Investigation of a 'natural' alternative to polyethyle MPs (walnut husk Mps) showed adsorption to these replacement particles occurred to a greater amount with more of the studied contaminants than to polyethylene MPs. This work significantly contributes to the knowledge of organis contaminant occurrence, bioaccumulation, fate and distribution in the aquatic environment. Future research should focus on elucidating the fate and distribution of conugated pharmaceuticals and metabolites in the aquatic environment, establishing organism-specific contaminant bioaccumulation guideline, the effect of microparticle fragmentation on contaminant adsorption, identification of adsorption-free MPs for use in cosmetic products and developing study designs to incorporate environmental epigenetics with toxicology and chemistry in the aquatic environment.

Objective: To assess the need for an adolescent cancer unit to serve the population in Yorkshire. Design: An epidemiological review of the data from two sources in the Northern and Yorkshire Region. A qualitative methodology was employed to assess the views of patients, healthy adolescents and staff on a unit away from the centre dealing with adolescents, on the benefits of a centralised adolescent unit. Interventions: None Results: Routine cancer registration data on 2411 adolescents registered with cancer between 1985 and 1994 were collected from the Northern and Yorkshire Cancer Registry and the Northern Children's Tumour Registry. The data related to 1375 patients in the former Yorkshire Region and 1036 patients in former Northern Region. Incidence data are presented for the two regions. Survival differed significantly between parts of Yorkshire but this did not appear to relate to place of treatment or social class. In the former Northern Region some differences were also apparent in survival, but the content of the data did not allow analysis by social class. However, in both instances survival appeared to be better in areas close to the cancer centre which was counter-intuitive to the expectations based on the known social class gradients in the former Yorkshire and Northern Regions. The qualitative studies discovered the specific needs of adolescents with cancer (e.g. the importance of peer group support and maintaining their education) and suggested that there could be benefit from centralised, specialised management. However, there were considerable potential flaws in the data which may render such a conclusion as debatable. Conclusions: This study adds weight to the proposal for the development of an adolescent cancer unit in Yorkshire, however, this study is by no means conclusive because of the absence of available data to answer this question. The reasons why, overall support should be given to create an adolescent unit fall into four categories: philosophical (the need to provide services which recognise the specific needs of adolescents) qualitative (the ability of specialist units to provide a higher quality of care) pragmatic ( the ability to concentrate specialist skills in one location) and improved outcome, this study suggests that outcome, and survival in particular differs may differ significantly according to where people live, and that this may be related to the type of care they receive. Further studies are needed to explain the apparent survival differences in the region.

This thesis considers how research evidence can support the probation service in its work with offenders, addressing the questions: 'What methods are effective in offender rehabilitation?'; 'How can we know these methods are working in practice?' and 'How can research evidence underpin policy and practice in work with offenders?'. The thesis explores whether crime-reduction via work with individual offenders is a feasible aim, ethically and practically, and reviews how this fits with theoretical approaches to understanding crime, and as an aim of the probation service. The characteristics of effective and ineffective methods of intervention as described in research literature are reviewed, revealing a low level of consistency between research-syntheses as to the characteristics of effective interventions. Methods of research synthesis and meta-analysis are critically reviewed. Issues in evaluating offender-interventions are reviewed, focusing on the use of reconviction as an outcome indicator. The thesis presents research case-studies of five offender-interventions, selected to be representative of probation programmes. The impact of each intervention on reconviction is evaluated using a quasi-experimental methodology. The offending careers of over 700 offenders, in intervention and comparison groups, are analyzed. Three interventions show clear evidence of effectiveness, with a lower proportion of offenders in the intervention groups than in relevant comparison groups being reconvicted: 48 percent, 34 percent (these finding were statistically significant), and 18 percent fewer offenders in the intervention group were reconvicted within one year. In this latter case-study of an evidence-based cognitive-skills training programme, offenders who showed positive change in attitudinal measures were more likely to be reconvicted. The implications of this finding for programme-evaluation methods are discussed. The thesis concludes by considering what these findings convey about effective ways of working with offenders, and how the findings contribute to an evidence-based approach in the probation service's work with offenders.

The lay magistrates' court system in England and Wales has, for centuries, permitted the detailed involvement of thousands of ordinary legally unqualified members of local communities in decisions which can have a profound effect on the lives and liberties of their fellow citizens. The role of magistrate is, therefore, important, and, for centuries, 'the great and good' monopolised local law enforcement and social control on behalf of the state. However, as this thesis suggests, the rather ad hoc, piecemeal development of the system allowed imbalances and inequalities to arise, and despite repeated efforts to reform the system in both regards, two principle criticisms remain: perceived sentencing inconsistency and social imbalance. The thesis suggests that there is a connection - denied in conventional rhetoric about criminal justice - between these two areas, a connection which is best understood via the concept of 'court traditions': habitual practices, attitudes and beliefs developed within the magistracy and, more particularly, within local benches, which allow 'non-legal' factors to influence decision-making and which perpetuate particular traditional views of the position and role of magistrates. These explanations can even utilise contradictory conceptions of the lay justice system, parading faults in one view as virtues in another. To investigate these 'traditional views', the researcher studied almost 300 lay justices and their professional colleagues at nine different English magistrates' courts. The study updates previous research about the social composition of the magistracy and - having developed a definition of 'court traditions' - examines how far this corresponds to respondents' own perceptions of the workings of the system. Attention was not only focused at the local grassroots level of lay involvement in the criminal justice system, for the researcher also studied the role of the lay justices' representative organisation, the Magistrates' Association. Possibly for the first time, the detailed working and position of this widely respected and influential group are critically discussed, and parallels are drawn between the roles of the Association and of lay justices in preserving the status quo inequalities of power and wealth of modern society