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G protein-coupled receptors (GPCRs) are a superfamily of membrane proteins that transduce extracellular signals to invoke physiological responses. Class B GPCRs are regulated by peptide hormones and are characterised by a seven transmembrane domain, a 120-150 residue extracellular domain (ECD), and an intracellular C-terminus. The parathyroid hormone 1/2 receptors (PTH1R/PTH2R) belong to this family and, despite being closely related, have different physiological roles: PTH1R is crucial in bone metabolism, whereas PTH2R function is significantly less well defined. The original aims of this research were to solve the structures of these two receptors. This involved creating various receptor constructs that would be suitable candidates for downstream structural trials. Insect cell expressed receptors were quantified through fluorescent intensity densitometry analysis and a potential candidate for further structural studies was found in the form of a mini Gs protein bound to an apocytochrome, b562RIL (BRIL) fusion protein following a FLAG purification. However, a constitutively active receptor, created by tethering PTH(1-14) to BRIL-PTH1R and verified through LANCE® cAMP assays, was unable to form this complex. PTH2R proved a major challenge, so attempts to solve the isolated ECD were made instead. This was pursued using Escherichia coli expressed protein in various oxidising environments, though due to low protein yields and poor stability it was impossible to obtain a candidate for further trials. Finally, the novel integral membrane protein stability selector (IMPROvER) program was used to create a thermostable PTH1R. Through fluorescent based thermostability assays, 40% of 20 mutations were stabilising with a maximum increase of 3.4 ± 1.1 °C. Combinations of these mutations resulted in a construct with an improved stability of 10 ± 0.76 °C. This research gives a strong foundation for future structural work regarding PTH1R and has highlighted that IMPROvER is a valid alternative to more laborious methods such as alanine scanning.

National approaches to climate change mitigation and adaptation have a central role to play alongside international law and policy and sub-national initiatives. The UK Climate Change Act 2008 (CCA) was one of the first examples of comprehensive climate change legislation in the world. In its original form, the law committed the UK to reduce greenhouse gas emissions by 80% by 2050, created a 'Carbon Budget' system of intermediary targets, created a procedure for adapting to climate change and established the Committee on Climate Change (CCC), an expert advisory body to the UK Government and the devolved countries. In 2019, recent scientific and political developments resulted in a new net zero target being set for 2050. This thesis attempts to understand why the UK responded to the challenge with legislation, why the law was designed in the way that it was and how it has been implemented. The thesis is primarily based on research interviews with a range of actors (politicians, civil servants, experts) conducted between February 2016 and July 2017, with complementary analysis of the law and relevant documents from the Government and the CCC. The approach of the thesis reflects the design of the CCA and applies social science and environmental law theory and scholarship on the relationship between law/policy, politics and science/expertise, especially principles of legal design and the idea of co-production. The research chapters focus on: the period of advocating for better approaches to climate change in the years 2000-2005; the establishment of the NGO campaign, the 'Big Ask' and its effect on government; the political process; the design of the CCA; the role of pre-legislative and legislative (parliamentary) scrutiny; the setting up of the CCC; the implementation of the CCA, specifically the influence of the Carbon Budget system; and the influence, functioning and advice of the CCC. The thesis juxtaposes the desire for the depoliticisation of climate change in the UK and the reality of a highly politically mediated process. The CCA and the CCC reflects a pragmatic response to the challenges of climate change for policy in the UK and appears to have had some influence on Government decision-making.

Inflammasome-controlled immune responses such as IL-1β release and pyroptosis play key roles in antimicrobial immunity and are heavily implicated in multiple hereditary autoimmune diseases. Despite extensive knowledge of the mechanisms regulating inflammasome activation, many downstream responses remain poorly understood or uncharacterised. The cysteine protease caspase-1 is the executor of inflammasome responses, therefore identifying and characterising its substrates is vital for better understanding of inflammasome-mediated effector mechanisms. Using unbiased proteomics, the Shenoy grouped identified the ubiquitin conjugating enzyme UBE2L3 as a target of caspase-1. In this work, I have confirmed UBE2L3 as an indirect target of caspase-1 and characterised its role in inflammasomes-mediated immune responses. I show that UBE2L3 functions in the negative regulation of cellular pro-IL-1beta via the ubiquitin- proteasome system. Following inflammatory stimuli, UBE2L3 assists in the ubiquitylation and degradation of newly produced pro-IL-1b. However, in response to caspase-1 activation, UBE2L3 is itself targeted for degradation by the proteasome in a caspase-1-dependent manner, thereby liberating an additional pool of IL-1beta which may be processed and released. UBE2L3 therefore acts a molecular rheostat, conferring caspase-1 an additional level of control over this potent cytokine, ensuring that it is efficiently secreted only in appropriate circumstances. These findings on UBE2L3 have implications for IL-1-driven pathology in hereditary fever syndromes, and autoinflammatory conditions associated with UBE2L3 polymorphisms.

In recent decades, the high strength, high toughness and appealing aesthetics of Yttria-Partially-Stabilised Zirconia (YPSZ) has made this ceramic the material of choice for dental prostheses. During manufacture YPSZ copings are veneered with porcelain to match the appearance of natural teeth and to reduce wear. However, near-interface chipping of the veneer is observed as a persistent primary failure mode. Recent studies suggest that failure is associated with the mechanical and microstructural state within a few microns of the interface. This insight has provided the motivating driver for this study: to develop and implement new characterisation techniques to improve the understanding of the YPSZ-porcelain interface and thereby reduce failure rates. Microscale characterisation of the interface was performed using energy dispersive X-ray spectroscopy, Raman spectroscopy, X-ray Diffraction (XRD) and transmission electron microscopy. These studies indicated that YPSZ phase variation, elemental composition gradients and distinct microstructural features are present within 10 μm of the interface. Porcelain nanoscale voiding was found at the interface, and small angle neutron scattering confirmed that this is induced by tensile creep. High resolution (microscale) residual stress analysis was performed in YPSZ using XRD and Raman spectroscopy, and in porcelain using a new pair distribution function analysis technique. Cross-validation of these results was performed using improved implementations of the ring-core focused ion beam milling and digital image correlation technique. The variation of Young's modulus, yield strength and fracture toughness were determined using spatially resolved micropillar compression and splitting. Improved evaluation of the single-crystal stiffness of YPSZ was also performed using a new neutron diffraction based technique. The results of this analysis indicate a complex interaction within the first 50 μm of the YPSZ-porcelain interface which leads to a significant reduction in porcelain toughness and an increased propensity to fail at this location.

Climate change has brought about legally-binding targets for Scotland, the U.K. and the E.U. to reduce greenhouse gas emissions and source a share of overall energy consumption from renewable energy resources by 2020. With severe limitations in the transport and heating sectors the onus is on the electricity sector to provide a significant reduction in greenhouse gas emissions and introduce a substantial increase in renewable energy production. The most attractive renewable energy resources are located in the geographic extremes of the country, far from the large population densities and high voltage, high capacity transmission networks. This means that the majority of renewable generation technologies will need to connect to the conventionally passive, lower voltage distribution networks. The integration of Distributed Generation (DG) is severely restricted by the technical limitations of the passively managed lower voltage infrastructure. Long lead times and the capital expenditure of traditional electricity network reinforcement can significantly delay or make the economics of some renewable generation schemes unviable. To be able to quickly and cost-effectively integrate significant levels of DG, the conventional fit-and-forget approach will have to be evolved into a ‘connect-and-manage’ system using active network management (ANM) techniques. ANM considers the real-time variation in generation and demand levels and schedules electricity network control settings to alleviate system constraints and increase connectable capacity of DG. This thesis explores the extent to which real time adjustments to DG and network asset controller set-points could allow existing networks to accommodate more DG. This thesis investigates the use of a full AC OPF technique to operate and schedule in real time variables of ANM control in distribution networks. These include; DG real and reactive power output and on-load-tap-changing transformer set-points. New formulations of the full AC OPF problem including multi-objective functions, penalising unnecessary deviation of variable control settings, and a Receding-Horizon formulation are assessed. This thesis also presents a methodology and modelling environment to explore the new and innovative formulations of OPF and to assess the interactions of various control practices in real time. Continuous time sequential, single scenario, OPF analyses at a very short control cycle can lead to the discontinuous and unnecessary switching of network control set-points, particularly during the less onerous network operating conditions. Furthermore, residual current flow and voltage variation can also gave rise to undesirable network effects including over and under voltage excursion and thermal overloading of network components. For the majority of instances, the magnitude of constraint violation was not significant but the levels of occurrence gave occasional cause for concern. The new formulations of the OPF problem were successful in deterring any extreme and unsatisfactory effects. Results have shown significant improvements in the energy yield from non-firm renewable energy resources. Initial testing of the real time OPF techniques in a simple demonstration network where voltage rise restricted the headroom for installed DG capacity and energy yield, showed that the energy yield for a single DG increased by 200% from the fit-and-forget scenario. Extrapolation of the OPF technique to a network with multiple DGs from different types of renewable energy resources showed an increase of 216% from the fit-and-forget energy yield. In a much larger network case study, where thermal loading limits constrained further DG capacity and energy yield, the increase in energy yield was more modest with an average increase of 45% over the fit-and-forget approach. In the large network where thermal overloading prevailed there was no immediate alternative to real power curtailment. This work has demonstrated that the proposed ANM OPF schemes can provide an intelligent, more cost effective and quicker alternative to network upgrades. As a result, DNOs can have a better knowledge and understanding of the capabilities and technical limitations of their networks to absorb DG safely and securely, without the expense of conventional network reinforcement.

Membrane filtration is a simple concept for water purification: water containing particulate contaminants is forced through a semi-permeable membrane that rejects the particulates leaving clean water to flow out. Nevertheless, there are many complex features of membrane filtration, the most important of which is the accumulation of the particulates at the membrane surface. This leads ultimately to fouling of the membrane and a reduction in the efficiency of the process. Concentration polarization is the precursor of fouling, that is, a high concentration of contaminants develops in front of the membrane without the contaminants attaching to each other or the membrane surface. However, several types of acute membrane fouling develop from the layer formed in concentration polarization, including internal fouling, pore blocking and caking. Addressing these and related problems has been at the forefront of membrane research since the process' inception. In this thesis we develop mathematical models of aspects of crossflow and directflow filtration operating at constant flux. We begin by addressing questions related to the initial stages of concentration polarization in crossflow systems. In particular, we study the influence of particulates on the viscosity of the filtrate, and show how the filtration efficiency may be improved by tailoring the wall permeability to reduce the effects of osmosis. We then address the development of membrane fouling and caking in directflow systems: the transmembrane pressure difference, the possibility of elastic deformations during filtration, and the influence of these on the development of fouling and caking are all considered. We show that even small elastic effects can worsen fouling and suggest how the process can be operated to avoid this. We then discuss further opportunities for mathematical modelling in this area.

This thesis places pressure on common distinctions between rhetoric and ideology, ideas and arguments, semantics and form, by examining the use of freedom rhetoric in political speech and propaganda in post-war Britain. To do so it combines a sophisticated statistical analysis of large volumes of text with the qualitative methodologies of rhetorical analysts and political historians. In particular, it uses custom software written by the author to apply the techniques of corpus linguists, content analysts, and political scientists to a corpus of every speech made in the House of Commons between 1936 and 1990. By integrating data sources, the thesis recovers a partisan variable unrecorded in Hansard that enables the systematic detection of differences between Labour and Conservative MPs' speech for the first time. Chapter one both describes the novel techniques deployed and identifies changes in the use of freedom rhetoric over time as well as partisan sub-languages of debate. This quantitative analysis provides the context for a detailed qualitative analysis of Conservative party rhetoric between 1945 and 1970 over three further chapters. Combining archival research with theoretical insights from rhetoric and framing scholars, it proposes a series of corrections to the party's post-war historiography, which has often wrongly equated freedom rhetoric with 'neoliberalism' or proto-Thatcherism and therefore misunderstood the complex beliefs and contexts generating this rhetoric. Moreover, because the continued use and adaptation of freedom rhetoric between 1951 and 1970 has been neglected, the thesis argues that historians have mischaracterised post-war Conservative politics as materialistic, underplayed freedom's role in Harold Macmillan's oratory, missed an important moment of transition under Alec Douglas-Home, and falsely charged Edward Heath with either betrayal or insincerity. These narrower debates provide a new perspective on the bigger question of why freedom persisted as a major concept in political discourse. Over its chapters, the thesis develops the notion of a 'rhetorical culture', which challenges the binary between rhetoric and ideology and can explain Conservative politicians' use of similar rhetoric to articulate dissimilar beliefs.

Dental pulp contains mesenchymal stem cells (MSCs) similar to those present within bone marrow. Several factors are postulated to contribute to the signalling involved in regulating these cells. This project aimed to investigate the role of pulp and dentine extracellular matrix (pECM/dECM) in the regulation of pulp cell behaviour during health and disease. pECM/dECM molecules were extracted using 10% EDTA, pH7.2 followed by 0.5M-NaCl, pH11.7 and 0.1M tartaric acid, pH2.0, respectively containing protease inhibitors. Proteomic analysis demonstrated the complexity of the ECM extractions. pECM-coated cultureware reduced pulp cell proliferation rates and increased stem cell marker expression compared with controls. Pulp cells exhibited multipotential capacity, with pECM-coated culture surfaces enhancing differentiation activity. pECM and dECM promoted pulp cell migration through an active rho dependent pathway and the chemotactic effects of these ECM molecules were enhanced following acidic/proteolytic degradation. Recruited cells exhibited increased stem cell marker expression. dECM and pECM possessed demonstrable bacteriostatic activity against three anaerobic bacteria associated with dental disease. Dental pulp cells were shown to be viable and capable of secreting mineral when encapsulated within a pECM/alginate scaffold and exposed to dECM molecules. Dental ECMs play important roles in regulating cellular and tissue responses during health and disease.