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Silicone is implanted widely in aesthetic and reconstructive surgery. The resultant immune response is poorly understood but implicated in two divergent capsular pathologies: fibrosis (capsular contracture, CC) and lymphomagenesis (breast-implant associated anaplastic anaplastic large cell lymphoma, BIA-ALCL). In this doctoral thesis, I have sought to characterise the immune response to silicone using an in vivo mouse model of capsular fibrosis. The primary hypothesis is that smooth and textured silicone surfaces elicit differing cellular, transcriptomic and proteomic immune responses that are pathologically significant. A model of capsular fibrosis was developed by implanting smooth and textured silicone breast implant shells in the dorsum of irradiated and unirradiated immune-competent C57BL/6J-WT mice. Implant capsules were excised at serial post-operative time points prior to morphometric, flow cytometry, immunohistochemical and immunofluorescent characterisation. RNA-seq and total proteomic analysis were undertaken to delineate transcriptomic and proteomic differences across in vivo samples according to surface. Median capsular thicknesses increased between early and late time-points with collagen laid down within the first 2 weeks (w) post-implantation then remaining static. Immunohistochemistry demonstrated early CD45+ (pan-leukocyte) and F4/80+ (macrophage) capsular infiltration that subsequently declined. Immunofluorescence was confirmatory. Further evidence for the immunogenicity of smooth implant capsules was provided by flow cytometry where statistically significant increases in T- (CD3+, CD4+ and CD8+), dendritic and NK cells were seen at 4 w as well as greater macrophage responses. RNA-seq found adipogenesis, oxidative phosphorylation, fatty and bile acid metabolism hallmark pathways to be upregulated in textured compared to smooth implants at 12 w post-implantation. Gene analysis found smooth implants to discordantly express myogenic and fibrotic pathways at 12 w with downregulation of cell cycle processes. Chemokine analysis found IL6 and IL10 to be elevated in all capsules at 1 w and 12 w post-implantation. Proteomic analysis demonstrated correlation between proteomic and RNA-seq datasets with fat metabolism proteins elevated in textured relative to smooth implant capsules but less clarity evident for immune-related proteins. In conclusion, smooth and textured implant surfaces elicited differing but temporally dynamic immune responses. Immunogenicity of smooth implants capsules was matched with a transcriptomic propensity for fibrosis but not proliferation. Textured implant capsules upregulated lipid metabolism divergently as compared to smooth implants and we postulate that this has modulatory implications for immune cells. Further work is necessary to correlate findings of the in vivo experiments against pathological human capsular tissue derived form our translational study of Breast-implant Associated anapLastic large cell lymphoma and Capsular contracture (BASILICA).

Dictyoxetane is a diterpene natural product isolated in 1985 along the coast of India, and it has not been found since. The structure consists of a trans-hydrindane unit, and the dioxatricyclic core which contains an oxetane moiety. There have been several publications demonstrating the synthesis of the dioxatricyclic core or similar structures, and a single report of the trans-hydrindane unit featuring a ketone for further elaboration. Despite this, the total synthesis of dictyoxetane has only been achieved once in the last 36 years, and as such further investigation is warranted. The literature surrounding dictyoxetane and methods to synthesise structurally similar fragments are critically reviewed in Chapter 1. Chapter 2 contains studies toward the asymmetric synthesis of (+)-dictyoxetane via a cycloaddition approach, which require a key furan intermediate. The synthesis of this intermediate via haloformylation and enynol cyclisation-isomerisation is detailed. An investigation of the reviewed [4+3] and [4+2] cycloaddition methods to construct the oxabicyclo[3.2.1]octane base of the dioxatricyclic core was undertaken. One of the methods failed to yield an isolable oxabicycle, while the other three were either poorly selective or the resulting products could not be advanced toward (+)-dictyoxetane. The final section of chapter 2 describes the use of a chiral auxiliary in a Diels-Alder reaction with the furan intermediate, resulting in a pair of regioisomeric oxanorbornenones. The ring-expansion of these strained ketones to the oxabicyclo[3.2.1]octane substructure is examined but remains inconclusive as a route to synthesising (+)-dictyoxetane. Chapter 3 contains a conclusion of the work, and suggestions for further work should the project be continued past the work in this thesis. Chapter 4 details the experimental procedures and data for all compounds reported as part of the work. Chapter 5 contains all the cited references. Finally, following the references are the appendices, which contain all the characterisation data for synthesised compounds including NMR, MS, IR, and X-ray data.

Background Understanding why mortality in children and young people (CYP) in the UK is higher than similar high-income countries can inform efforts to improve outcomes. Methods I used data from the World Mortality Database, Office for National Statistics, and Global Burden of Disease Study to describe current patterns and long-term trends in UK CYP mortality, and compare this to a group of similar countries (the EU5+). I then used Hospital Episode Statistics data to understand how health service factors may contribute to the UK's poor outcomes, and identify patterns of healthcare activity associated with mortality hazard. I finally place concerns regarding UK adolescent mortality in an international context, and examine global trends in deaths in 10-24 year olds. Results I found large differences in rates of mortality decline in the UK by age group and cause, with adolescents lagging behind other age groups. Improvements in UK mortality since 1970 have also been slower than the EU15+. I found the UK to currently have significantly higher CYP mortality for respiratory conditions, neurological conditions, common infections, and diabetes and endocrine conditions, but good outcomes for injuries. I found some areas of England to have mortality rates comparable with the best performing EU15+ countries, and that levels of deprivation explain much of the geographic variation in UK CYP mortality. Amongst CYP admitted with epilepsy, asthma and diabetes, (conditions where the UK has high mortality), recurrent attendances to hospital, missed appointments, mental health contacts, and difficulties transitioning to adult services, were all associated with increased mortality hazard. Global trends in adolescent mortality mirrored concerns in the UK, with poor progress compared with younger groups, despite most causes of death being preventable. Conclusions Interventions to improve UK CYP mortality require action across multiple health determinants. This should include addressing high levels of CYP poverty, but also further examination of the contribution of health service factors.

Foot-and-mouth disease virus (FMDV) is a single stranded RNA virus in the picornavirus family. It is the causative agent of foot-and-mouth disease, globally the most important a�iction of cloven hoofed animals. The FMDV genome has several features that are not found amongst other viruses within the Picornaviridae. These include a large 50 untranslated region (UTR), almost twice the length of that found in enteroviruses, containing highly structured RNA elements unique to FMDV, such as the S-fragment and several tandemly repeated pseudoknots. Unique aspects are also found within the coding region, where FMDV is the only picornavirus reported to contain multiple copies of the 3B gene. The reasons behind possession of these unusual deviations from the dogma of the picornaviral genome is so far unknown and therefore poses an attractive target for further research. The S-fragment is a predicted 360 nucleotide stem-loop at the 50 end of the FMDV genome. The better studied poliovirus (PV) has a well characterised 80 nucleotide clover leaf structure in the equivalent position which is used as a model for potential S-fragment function. In close proximity to the S-fragment are a series of tandemly repeated pseudoknots, these pseudoknots are maintained across all sequenced isolates of FMDV, however, the number of pseudoknots varies between two and four depending on the specifc isolate. As with the S-fragment, no function is yet assigned to these pseudoknots and the reason behind the variation in number remains unknown. Here, biochemical probing of the S-fragment and pseudoknots has been used to confirm the secondary structures of these elements and helped inform mutagenesis experiments to disrupt conformations. Sub-genomic FMDV replicons are used in tandem with infectious virus to help dissect the roles of these elements in distinct areas of the viral lifecycle. Alongside RNA structure in the 50 UTR, this thesis also investigates the nonstructural P3 region and how the 3B protein plays a key role in correct polyprotein processing. The complex dynamics of picornavirus polyprotein processing generates intermediate products which expand the repertoire of functions encoded in the genome. Dissecting these processes is therefore key for understanding the details of virus replication. As the polyprotein of FMDV uniquely includes three tandem functional copies of the 3B primer peptide, the manipulation of P3 cleavage sites is used here to further uncover the roles of the 3B protein in replication. The importance of the C-terminal region of 3B3 for correct polyprotein processing is described as well as the capabilities for 3B proteins to accept C-terminal fusions, providing a novel set of molecular tools and approaches to further analyse the complexities of picornavirus genome replication in the future.

The PhD research presented here is part of the new nuclear manufacturing (NNUMAN) research group, looking into novel materials and manufacturing processes. NNUMAN is an EPSRC funded (EP/J021172/1) program with direct support from Rolls Royce plc. The fabrication of MAX phase coatings by different means and assessing their tribological properties was the original theme of this thesis. However, due to issues with fabrication processes the overriding direction was moved towards assessing the response of bulk MAX phases to irradiating and corrosive environments. It is believed that this research will contribute to the understanding of suitable compositions and applications within nuclear. The MAX phases comprise an early transition metal (M), an A-group element (A) and either carbon or nitrogen (X). They have an inherently nano-layered structure with alternating ceramic (MX) and metallic (A) layers. The unique mix of both ceramic and metallic properties have made MAX phases a proposed material for nuclear applications. Proton irradiation is performed on Ti3SiC2, Ti3AlC2, Ti2AlC and Cr2AlC bulk MAX phases to 0.1 dpa at 350oC. Crystallographic instabilities are observed through x-ray diffraction (XRD) analysis after irradiation. A mechanism for irradiation induced point defect swelling is proposed, by matching XRD and modelling data. Anti-site point defects are proposed to be a major contributor to anisotropic lattice parameter changes in Ti3SiC2. Additional carbon interstitial defects are also proposed in Ti3AlC2, as well as anti-site defects, making them less radiation tolerant. Further proton irradiations on Ti3SiC2 and Ti3AlC2 were performed at elevated temperatures to propose a temperature at which lattice changes are not observed. It is concluded that high proton fluences require temperatures in excess of ~700oC and ~1,000oC for Ti3SiC2 and Ti3AlC2, respectively. Corrosion of bulk MAX phases in simulated primary water also suggests a deleterious response to normal light water reactor (LWR) operations. Advanced scanning transmission electron microscopy (STEM) techniques, such as energy dispersive x-ray spectroscopy (EDS) and electron energy loss spectroscopy (EELS), is employed to understand corrosion mechanisms. Selective oxidation of A-layers is observed, with no evidence of passivation for Ti3SiC2, Ti3AlC2 and Ti2AlC. The response of Cr2AlC was most promising as little oxidation occurred, which is confirmed also with XRD analysis. A comprehensive corrosion mechanism is proposed, whereby compositions of MAX phase in LWR coolants is limited.

The work in this thesis is split into two parts. The introduction and following two chapters pertain to the investigation of gene regulation using Chip-seq data and linear modelling. The final chapter pertains to the prediction of hot-spot residues in protein-protein interactions. The rapid escalation in the speed and quality of DNA sequencing has lead to a wealth of data for the location of transcription factor binding and histone modifications across the genomes. Using Chromatin ImmunoPrecipitation followed by sequencing (ChIP-seq) data, we have generated a new binding metric based on the enrichment of the read-counts for each gene. Eight datasets from mouse macrophage cells (two histone modifications, five transcription factors, DNase I hypersensitivity) were used to model the binding of RNA polymerase II. It was found that a linear model just using the DNase I hypersensitivity and histone modification data was better than any of the models containing the transcription factor data. Investigation of the outlying genes for the model revealed no pattern in their Gene Ontology terms or macrophagespecific genes. Human embryonic stem cell data (23 transcription factor and 24 histone modification datasets) were used in combination with LASSO regression to model the binding of RNA polymerase II. The resultant models contrasted with the results from the mouse macrophage linear models in that using the histone modifications data in combination with the transcription factor data lead to the best models. A much more complicated picture of the regulation of RNA polymerase II binding was produced using the LASSO models. Protein-protein interactions are essential for every function within a cell and being able to predict them has large consequences for drug discovery and understanding the vast proteininteraction networks that occur within cells. Predicting protein-protein interactions is difficult due to the large number of possible conformations; predicting hot-spot residues can greatly reduce this. InterBasePro was compared with experimental data and subsequently adaptation was done to assess its usefulness for predicting hot-spot residues. An alternative approach was also made into classifying hot-spot residues based on atomic contacts.

The concept ofgenealogy has come to be seen in continental Nietzsche studies as cen~al to Nietzsche's project, indeed as designating the philosophical approach ofthe mature Nietzsche. I explore how this state of affairs has come about by reading the texts ofthree French-language writers whom I take to have particularly influenced the way continental philosophy, and even to some extent analytic philosophy, has come to see Nietzsche. Gilles Deleuze was the first to make genealogy central to his view ofNietzsche, but Deleuze's tendency to misleading abstraction in reading Nietzsche can be seen to have far-reaching consequences for many aspects of his interpretation, including his famous reading ofeternal return. Michel Foucault reminds us ofthe properly historical aspect of Nietzsche's philosophy, but turns genealogy into a historicism based on presuppositions quite other than those ofNietzsche. And in Jacques Derrida's adoption ofNietzsche as a forebear genealogy becomes bound up with conceptions ofopposition and self-reference which are quite foreign to Nietzsche's way of thinking. In the process ofexploring these tensions I contend that 'genealogy' is for Nietzsche a particular word tied to a particular field, that field explored in the text ofNietzsche's which bears the word in its title, On the Genealogy ofMorals, and definitely not a word which designates his philosophy as a whole. The concept of''Nietzschean genealogy' is not a substantial and solid textual object offering itself to interpretations which could be construed as its 'shadows'; rather there is from the start something shadowy about the very idea of'genealogy'. In demonstrating this I hope to open the way for a reading of Nietzsche's philosophy in which 'genealogy' is seen as a single aspect ofa much broader philosophical project.