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In this thesis we apply the methods of partition functions to massive superstring spectra and the moduli spaces, or spaces of zero-energy configurations, of supersymmetric QCD gauge theories. In the first part of this thesis we consider the massive covariant perturbative superstring spectra of compactifications of the type I open superstring preserving 4, 8 or 16 supercharges. There are an enormous number of ways in which the required amount of symmetry can be obtained, but here we concentrate on the `universal' states that are present in every possible compactification preserving that amount of supersymmetry. For each super-Poincar\'e representation we derive the multiplicity generating function, or the power series counting the number of times that representation occurs at each mass level, and from these we derive empirically the stable pattern or leading Regge trajectory that these multiplicity generating functions approach in the limit of large spin. For the mathematically tractable and phenomenologically relevant case of 4 supercharges we also derive these power series analytically and see that they agree with the empirical ones. In the second part we introduce the type of partition functions called Hilbert series, which count the number of algebraically or linearly independent polynomials at each graded level of a graded algebraic structure such as a (graded) ring, module or ideal. In supersymmetric gauge theories the algebraic structure is the chiral ring which is generated by the gauge-invariant operators of the theory. The specific theories we consider are supersymmetric generalizations of QCD, or SQCD, with exceptional or related (by sequence or folding of the Dynkin diagram or Higgsing) gauge groups with specified numbers of flavours of matter in specific representations. We show, as for theories with classical gauge groups, that the moduli spaces are Calabi-Yau manifolds and also demonstrate relations between the Hilbert series of SQCD theories related by Higgsing on one or more flavours of matter in specific representations.

The mantle is the most massive carbon storage reservoir on Earth. Interactions between surface and mantle reservoirs of carbon strongly govern atmosphelic chemistry and the habitability of our planet on geological timescales. The petrological and dynamical behaviour of carbon in mantle rocks promotes chemical differentiation and extraction of heat-producing elements through the migration of low-degree melts. Additionally carbonate melts mobilise hydrogen from nominally anhydrous minerals, which helps lower mantle viscosity and maintain active tectonics. I present four studies, each of which focusses on a different aspect of carbon's behaviour under high-pressure conditions. I study a suite of Brazilian diamonds and their mineral assemblages (Chapter 2). The isotopic signature of the host diamonds and mafic chemistry of their inclusion cargo reveals that they are fragments of recycled crust that has been exhumed from mid-mantle depths. In Chapter 3 I determine the melting curves of MgSi03- MgC03 and MgC03-CaC03, analogues of carbonated mantle material, between 15 and 80 GPa by performing experiments in the laser-heated diamond-anvil cell. Results from these experiments demonstrate that carbon-bearing lithologies will melt, potentially creating an isolated carbon reservoir, in the lower mantle. Chapter 4 presents multi anvil experiments that investigate the melting phase relations of carbonated MORB throughout the upper mantle. These reveal a solidus ledge that implies the transition zone can act as a carbon filter to downwelling material. This causes a narrow interval of melt production that could be geophysically observable and responsible for diamond formation. Finally, in chapter 5 I present experiments and geochemical modelling that tests whether diamond-hosted inclusion assemblages are compatible with a transition zone growth mechanism where slab-derived melts interact with ambient mantle material.

This thesis examines why the US has increasingly relied on proxy forms of intervention in counterinsurgency and unconventional warfare operations and support. Most existing studies on paramilitaries, mercenaries, and private military companies (PMCs) in US foreign policy analyze these actors separately from one another and tend to emphasize their relative newness in the post-Cold War security environment. In contrast, this thesis traces the continuity and evolution of the use of para-institutional actors in US-led and supported counterinsurgency and unconventional warfare engagements in the global South throughout the post-war period. It places this analysis in the context of US Open Door grand strategy and hegemonic role in the international system. In doing so, it develops a para-statal model of US foreign policy that is inclusive of the variegated connections between the US and para-institutional forces. The "para-state nexus", as I have labeled it, conceptualizes the intersection of the US and various parallel military formations and the ways in which they operate as a para-extension to US coercive reach. This thesis argues that the development and entrenchment of a para-state nexus is inextricably bound to US Open Door imperatives to "stabilize" favorable political and economic state arrangements in countries in the global South threatened by significant opposition "from below", conducive to US interests and the global capitalist system as a whole. Thus it posits that this "para-state nexus" is embedded in structural relations of the liberalized global order, and forms a central component of the US's managerial role in the international system. This presents an alternative historical account of the evolution of PMCs in US foreign policy, and demonstrates that practices such as the "Salvador option" have extensive historical roots in the prosecution of US modes of coercive statecraft abroad.

Reducing the amount of metal used within a timber structure has many advantages, particularly when dealing with connections. Fire resistance and durability are commonly cited benefits. In addition the use of alternative connector materials minimises thermal bridging and can also provide a lighter weight structural solution. Existing contemporary forms of non-metallic timber connections are commonly provided through the use of adhesives. However, these connections are reliant on a need for careful offsite, prefabricated construction. Traditional green oak carpentry connections provide a mechanically fastened non-metallic solution. However, carpentry connections are not widely compatible with contemporary architectural design or with the use of modern engineered timber products such as glulam. Building upon research completed at the University of Bath, the aim of this thesis was to develop a mechanical, non-metallic connection system suitable for contemporary applications. Specific objectives were to investigate the structural performance of a defined connection system and to develop analysis methods to facilitate design. A review of the literature demonstrated a lack of uptake and use of mechanical non-metallic connections. Guidance for the design of mechanical fasteners reflects the lack of innovation and research into the use of non-metallic materials. Following an initial experimental investigation of non-metallic materials, an experimental testing programme was completed to investigate the use of glass fibre reinforced plastic (GFRP) dowels in conjunction with densified veneer wood (DVW) plates. The findings of the experimental study demonstrate that the use of these materials can provide a robust connection system for contemporary applications. The results of the experimental work provide guidance on dowel spacing requirements, connection response to load and connection failure modes. The failure modes of the proposed connection system were shown to be unique to the materials used and specific strength analysis methods have been developed to predict connection yield and ultimate strength. A method for predicting initial connection stiffness was also developed through the use of a beam on elastic foundation model.

This thesis demonstrates ways in which the ammonium group can be used to template the formation of rotaxanes, and to control their submolecular motion. The first part details the development of a methodology for synthesising rotaxanes from cyclic peptide macrocycles. Cyclic octa- and deca- peptides of the L-ProGly repeat unit are versatile ionophores that are known to bind both metal ions and organic cations. One mode of binding exhibited by this type of macrocycle is to associate a cation on either face of the macrocycle: a so called ‘sandwich complex’. If the two cations with which the macrocycle binds are secondary ammonium groups connected by a spacer of suitable length, then an inclusion complex is formed. Trapping of this type of inclusion complex by covalent modification has allowed access for the first time to synthetic rotaxanes of cyclic peptides. The latter half of this thesis details the synthesis and operation of two different switchable molecular shuttles in which the position of the macrocycle is determined by a change in the protonation level of the molecule. The first of these shuttles operates by a combination of amide-amide and crown ether-ammonium interactions. In its neutral form these amide-amide hydrogen bonds hold the macrocycle over a dipeptide residue. When an amine group in the thread is protonated, polyether-ammonium cation interactions dominate and the macrocycle changes position. The second shuttle relies solely on crown ether-ammonium interactions. In this instance pH controlled movement is achieved by the selective deprotonation of one of two ammonium stations, inducing the macrocycle to reside predominantly on the second, less acidic, station.

Animal studies suggest that nitric oxide, a free radical derived from L-arginine by the action of nitric oxide synthase (NOS), is a fundamental mediator in the initiation of labour. The studies reported in this thesis have investigated the involvement of the L-arginine-nitric oxide system in the maintenance of myometrial quiescence and the initiation of parturition in human pregnancy. Further, the effects of nitric oxide donors on the pregnant human cervix have been determined. The studies reported in chapter 2, were performed to determine whether a decrease in NOS enzyme activity and expression are involved in the final activation of spontaneous labour at term. Using immunocytochemistry, each of the three isoforms of NOS was localised in myometrium, placenta and fetal membranes collected before and during labour at term. NOS enzyme activity in each of these tissues was determined by measuring the conversion of radiolabelled L-arginine to L-citrulline. There were no differences in either the expression or enzyme activity of NOS within each tissue following the onset of labour indicating that a decrease in NOS enzyme activity is not involved in the final activation of labour at term in the human. The enzymes superoxide dismutase (SOD) and xanthine oxidase (XO) are known to prolong and attenuate respectively, the biological activity of nitric oxide. Studies, presented in chapter 3, were therefore undertaken to determine whether changes in the uterine expression of these enzymes are associated with the onset of human parturition. Both SOD and XO were shown to be widely expressed within the pregnant uterus, although there was no difference in their expression in tissues collected before, compared with after the onset of labour. These data suggest that SOD and XO may be important in maintaining uterine quiescence in pregnancy, but that a change in the expression of these enzymes is not involved in the initiation of labour. In chapter 4, the expression of the constitutive isoforms of NOS, eNOS and bNOS, was investigated in the non-pregnant uterus, the preterm pregnant uterus and the term pregnant uterus to determine whether these isoforms are up-regulated in the uterus during pregnancy. Using immunocytochemistry and Western blotting, eNOS and bNOS protein concentrations were greater in preterm, pregnant myometrium than nonpregnant myometrium, (p<0.01 and p<0.05, respectively). eNOS, but not bNOS, protein concentration was lower (p<0.05), in myometrial samples obtained at term compared with those obtained preterm. These data indicate that the constitutive isoforms of NOS are upregulated in human pregnancy and may play a role in maintenance of myometrial quiescence. Concurrent histological studies on tissues obtained before and during spontaneous labour, reported in chapter 5, revealed that inflammatory cells infiltrate the myometrium during labour. Analysis of individual cell types using immunocytochemistry showed significantly more inflammatory cells, predominantly neutrophils and macrophages, in labouring myometrium compared to non-labouring biopsies, (Scheffe's test, p = 0.0001). The infiltrate was present in both lower and upper uterine segment myometrium, with significantly more inflammatory cells present in the lower uterine segment myometrium, (Scheffe's test, p < 0.02). These observations indicate that inflammatory cell infiltration is part of the physiological mechanisms that occur in the myometrium during labour. The cervical ripening effects of nitric oxide donors, isosorbide mononitrate (IMN, 40 mg) and glyceryl trinitrate (GTN, 500 mug), were determined in a prospective, randomised trial involving women scheduled for surgical termination of pregnancy in the first trimester. During the operative procedure, the cervical resistance was measured objectively using a force sensing apparatus. The data, presented in chapter 6, showed that both IMN and GTN significantly reduced the cervical resistance, compared with no treatment (p<0.006 and p<0.05, respectively). A further randomised trial involving 66 primigravid women was performed to compare the side effect profile of IMN in comparison with the prostaglandin analogue gemeprost. Significantly more women remained asymptomatic following IMN (64%) than following gemeprost (14%). Pretreatment with gemeprost resulted in abdominal pain in 73% of women and vaginal bleeding in 32%, compared with 3% and 0% respectively following IMN. These data, reported in chapter 7, suggest that nitric oxide donors may have advantages over the prostaglandins for cervical ripening. In summary, an up-regulation of NOS expression in myometrium during pregnancy suggests an involvement of the L-arginine-nitric oxide system in the maintenance of myometrial quiescence. A decrease in this system and in the expression of enzymes known to influence the bioavailability of nitric oxide, do not coincide with the onset of spontaneous labour at term, suggesting that a withdrawal of nitric oxide is not the final activating factor in the initiation of labour in women. This work has demonstrated that nitric oxide donors produce effective ripening of the human cervix in the first trimester of human pregnancy with fewer side effects than prostaglandins. Nitric oxide donors represent alternative cervical ripening agents, at least in the first trimester of human pregnancy.

Over 2.3 million U.S. citizens found themselves shipped to France in 1944-45, most of them ordinary men conscripted into the Army. This study centres on the experiences of these Americans in France - how they prepared for dealing with the French; their perceptions of France and its citizens on the eve of their arrival; the welcome they experienced, the giving and receiving of help; the changing relationship in the differing phases of the Liberation; and the legacy of the interaction - its immediate legacy, and the legacy of veterans' feelings towards the French in the 1990s. How the interation of ordinary Americans and French worked out is the key theme. The study draws primarily on U.S. Army records, records of Civil Affairs operations, and the results of the author's questionnaire of veterans with experience of France. Following an overall good interaction in Normandy, Franco-American relations on the ground reached a highpoint with the sweep across northern France and the invasion of southern Franch in Auguts 1944. In the twelve months from September 1944 there was a serious deterioration in relations, the principal factor being the effect of the passage of time. However, although the experience thus ended on a very low note, on balance the interaction had worked out reasonably well. Given the circumstances - that it was wartime, that the war dragged on for much longer than it had appeared that it would, that soldiers everywhere are likely to contain a rogue element, and that there was a language barrier - the interaction was a healthy one on balance. Because the American involvement was devoid of overtly colonial or bad historical overtones, it was more straightforward than it would otherwise have been and bore up reasonably well under the strains that did afflict it - a mix of practical and cultural strains, rather than 'colonial' ones.

Obligately anaerobic bacteria of the genus Bacteroides are important and abundant inhabitants of the rumen and hind gut of mammals. They are the most numerous group in the rumen and play a major role in fibre degradation with the rumen. They are phylogenetically remote from the better studied groups of facultatively anaerobic gut bacteria (eg. enterobacteria), but are closely related to the colonic Bacteroides. Interstrain conjugal transfer of a plasmid, pRRI4 (coding for tetracycline (Tc) resistance), from the multiple plasmid bearing B.ruminicola strain 223/M2/7 to F101, a rifampicin resistant mutant of B.ruminicola B 14, was demonstrated. pRRI4 was demonstrated to be self transmissible and carried the genes coding for TcR in B.ruminicola. Transformation of B.ruminicola F101 to Tc R with pRRI4 was achieved using electroporation at frequencies up to 106 per mug DNA. Four other B.ruminicola strains were not transformed with this plasmid nor was a strain of B.uniformis. Similar procedures gave transformation of B.uniformis strains, but not B.ruminicola strains, with the E.coli:Bacteroides shuttle vectors pDP1 and pE5-2 at frequencies up to 107 per mug DNA. A nuclease assay was developed to determine the nuclease activity of a number of rumen bacteria and high nuclease activity in all B.succinogenes and five B.ruminicola strains was demonstrated. E.coli and B.uniformis strains were also transformed using electroporation by the shuttle vector, pRRI207, which has been constructed from a cryptic B.ruminicola plasmid (pRRI2, 3.4kbp) cut with EcoRI *, an E.coli vector plasmid (pHG165, 3.37kbp) carrying the pUC8 multiple cloning site, and the 4.2kbp Cc-EmRTc R* EcoRI region of pDP1. pRRI207 is capable of transforming B.uniformis, B.distasonis and B.ruminicola to clindamycin (Cc) resistance and E.coli to TcR (only expressed aerobically), and was the only construct from eleven different constructs obtained based on pRRI2 able to do so.