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It is critical to determine whether ERM creates value to ensure that the significant resources deployed in ERM programmes result in tangible corporate value. This thesis analyses the valuation implications of ERM maturity using The Risk and Insurance Management Society Risk Maturity Model (RIMS RMM) data collected from 2006 to 2011 using a 5-point maturity scale. The results, measured by Tobin’s Q, suggest that firms that have reached mature levels of ERM exhibit higher firm values, demonstrating a statistically significant positive relation to the magnitude of 25 percent. Upon decomposition of the maturity score, the most meaningful aspects of ERM relate to top-down executive engagement and the resultant cascade of ERM culture throughout the firm. In addition to serving as one of the first studies to establish strong empirical evidence for ERM increasing firm value, the thesis extends its contribution to examine the firm performance implications of ERM maturation under different models, specifically identifying characteristics that engender or inhibit the aforementioned valuation implications. A discussion of how an ERM programme could significantly affect an organisation’s policies and relationship with stakeholders is also explored. ERM is theoretically projected to be a means to help strengthen the relationship that companies have with regulators, reinforce or repair relationships with shareholders, strengthen interactions with supply chain stakeholders, enhance reputational relations with clients and improve auditor partnerships. The thesis concludes by arguing that ERM has now reached a critical mass, such that further adoption and development of the ERM discipline is now inevitable.

Lower back pain places an enormous economic burden on society and health authorities as it affects up to 80% of the population and has been attributed to intervertebral disc injury as well as the degenerative adaptations which occur with advancing age. Much of our understanding of disc mechanics comes from mathematical and finite element models; however, there is a lack of empirical data which is required for model validation. Additionally, the influence of mechano-electrochemical phenomena on fundamental mechanical properties such as permeability and Poisson's ratio is still not fully understood. Therefore, this thesis aimed to investigate the influence of such phenomena on disc mechanics whilst providing a comparison between multiphasic FE models and experimental data. Direct permeation experiments found that fluid velocity may be augmented through the nucleus pulposus via ionic osmotic pressure gradients which consist of fixed charge, mobile ion and electrical potential gradient s. A novel method to fully characterise, for the first time, the Poisson's ratio of the disc was developed. Poisson's ratio of the nucleus pulposus was found to be strain dependent and lower than previously thought, whilst solid matrix viscoelasticity may influence disc mechanics at high strain-rates. Confined compression experiments on the degenerate human nucleus pulposus found that the solid matrix bears the majority of load under axial compression due to the depletion of proteoglycans and the consequential reduction in mechano-electrochemical effects in this tissue. Poor agreement with biphasic theory may provide evidence of the degenerate nucleus pulposus exhibiting a heterogeneous structure and a dual permeability phase. Multiphasic models were developed and compared to experimental data. Differences were found between biphasic and triphasic models which resulted in varying agreement with experimental data thus the correct selection of numerical framework was found crucial when investigating disc mechanics. The data presented in this thesis are important for informing our overall understanding of disc mechanics, aiding the development future models as well as providing a benchmark for potential replacement materials to be critiqued against, particularly in terms of permeability and fluid pressurisation which are crucial to the load bearing capacity of the tissue.

The production of large amounts of Municipal Solid Waste (MSW) is an inevitable consequence of today's consumer society. Finding safe, sustainable, socially acceptable and cost effective alternatives to the disposal of MSW in landfills represents a major challenge to the waste management industry, and one that was set out in law under the European Landfill Directive in 1999. Composting is seen as an attractive waste management option, providing that there are few negative effects on the environment after undertaking a life cycle assessment. The focus of the research presented in this thesis is on the composting of MSW, both mixed and source-segregated, and the subsequent use of these composts in the remediation, land reclamation and horticultural industries. Composts were produced in two runs on an industrial scale using the EcoPOD® in-vessel composting system, and changes in key compost quality indicators (e.g. C:N ratio, nutrient and heavy metal availability) were quantified during the composting process (Chapters 3 & 6). Due to UK regulations on wastes containing animal by-products, no field trials were possible using the composts produced in the studies presented in this thesis. Instead, a series of pot trials were carried out over Chapters 3-6, with a mesocosm-scale trial used in Chapters 7 & 8. Of these trials, Chapter 3 investigated potential uses for mixed-waste compost produced using the EcoPOD® system, and found it to be particularly suited to remediation of acidic, heavy metal contaminated soils. This theme of remediation was carried on through Chapter 4 on the pot scale, and Chapters 6 & 7 on a mesocosm scale studying migration of heavy metals down the soil profile over time. Work in Chapter 5 focussed on the difficult subject of ecologically sensitive revegetation of blocky slate waste using composts amended with sulphur and iron hydroxide to make them more suitable for upland restoration purposes. Analysis of soil solution pH and P concentration proved promising with pH being decreased by s0, and P being reduced by Fe(OHh, however the amendments failed to influence above-ground plant diversity trajectories. Finally, nutrient rich composts produced in Chapter 6 was assessed for their potential as a replacement for peat in horticulture, and demonstrated that a 75 % substitution for peat based growing media is possible without affecting plant growth and yield. In summary, this work has demonstrated that highly contrasting organic wastes can be successfully composted, and has found that even low-quality mixed waste composts may be successfully used in the biostabilisation of acidic, heavy metal contaminated soils. In fact, the high buffering capacity of the MSW compost produced in this study (Appendix 1) lends itself to this role, providing a strong ability to resist pH change from the pyritic nature of the soil used throughout these studies (Chapters 3, 4, 6 & 7) . In order to assess the contribution of compost-borne heavy metals to the overall burden, further work using isotopic analysis could be utilised to pinpoint contaminant sources (Appendix 2). The use of chemical amendments to reduce compost pH and P availability showed promise, but further work is required in this area to optimise the amendments. Finally, composts derived from catering wastes w ere found to provide a real alternative to peat in horticulture, although such wastes are yet to attain full market acceptance.