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In this thesis, atomistic simulations of the specific adsorption of tetrabutylammonium tetraphenylborate (TBA+TPB-) have been performed for the first time. Three different systems have been analysed; DCE(TBA+TPB-)/vapour, DCE(TBA+TPB-)/pure water, DCE(TBA+TPB-)/water(Na+Cl-). The ions have been shown to change the bulk properties of the electrolyte but only change the non-electrostatic interfacial properties in the DCE/vapour system. TBA+TPB- has been seen to specifically adsorb at all the interfaces simulated. Due to the more compact nature of the TPB- ion, the TBA+TPB- charge separate in the adsorption equilibrium. For DCE/water and the interface of two immiscible electrolytic solutions (ITIES), the adsorption of the ions recede from the interface engendering the interface resistance to change for properties such as surface tension and interfacial width. The adsorption of salt at the DCE/water interface shows significant charge overscreening beyond 0.08m but no such overscreening is seen at the DCE/vapour interface. Due to the charge separation at the interface, an electric field is generated seen as a shoulder in the electrostatic potential distributions. The presence of salt at the interface also changes the bulk-bulk potential drop. For the ITIES, on charging, the bulk density of DCE was seen to increase. The field also has an effect on the dumbbells and when the field does not support the negative TPB- to be present at the interface, the dumbbells are destroyed which negates the electric field that had been generated by the charge separation. The properties of the solvent, interface and ions (bulk and interfacial) in all cases have been measured. Large errors were seen in the measurement of surface tension and differential capacitance, however, the thesis presents a novel description on the specific adsorption of TBA+TPB- at the ITIES.

Global biodiversity is in decline, with the marine environment experiencing significant and increasing anthropogenic pressures. As a response, very large (105–106 km2) marine protected areas (MPAs) have become the dominant form of environmental protection in the marine environment. At present, however, paucity in scientific sampling makes prioritising which regions of the ocean to protect, especially over such large spatial scales, particularly problematic. One such very large MPA, covering an area of over 1 million Km2, is located at the sub-Antarctic South Georgia and South Sandwich Islands (SGSSI). This study uses the SGSSI MPA as a model system to assess the application of benthic habitat mapping as an evidence-based framework for the spatial prioritisation of marine conservation. This study presents an interdisciplinary methodology to marine landscape mapping, as a top-down, objective statistical approach to hierarchically partition and map the benthic environment into physical habitats types. Ordination analysis demonstrates a statistically significant relationship between environmentally-derived landscape mapping clusters and the composition of benthic species data from the region, thus attributing ecological relevance to the marine landscape map. Furthermore, this study adopts a bottom-up approach to habitat mapping, using an ensemble of habitat suitability models. Potential distributions are modelled for a range of benthic faunal attributes relevant to marine management, based on taxonomic classification, functional traits and vulnerability to disturbance. These modelled distributions are used to describe, for the first time, the bio-physical characteristics of SGSSI’s benthic environment. Synthesising both top-down and bottom-up approaches to habitat mapping, this study assesses the physical landscape clusters and modelled distribution results in relation to the spatial protection currently enforced at SGSSI. This synthesis addresses, (i) whether marine spatial planning in the region is representative in terms of the habitats and fauna it protects; and (ii) whether this interdisciplinary methodology at SGSSI can inform on MPA design and designation more universally, in what is an increasingly exploited, yet still poorly understood marine environment.

Many orchids are rare and endangered due to habitat loss, degradation and human interference. This thesis aims to improve our understanding of orchid-mycorrhiza relationships and optimise methods for successful in vitro germination and development of terrestrial and epiphytic orchids. The research undertaken advances our understanding of orchids and has applications for conservation and horticulture. Fungal specificity plays a key role in orchid distribution and the colonisation of habitats. This was investigated in the Australian terrestrial orchid, Microtis media R. Br. in Chapter 2. Experiments demonstrated low fungal specificity in germination in vitro, although later development was more specific, with one fungus inducing protocorm development through to adult plants. Fungal compatibility was tested in several Eurasian terrestrial orchids in Chapter 3. Varying degrees of specificity were observed, with Anacamptis morio (L.) R.M.Bateman, Pridgeon & M.W.Chase and Dactylorhiza incarnata (L.) Soό displaying low fungal specificity whereas Serapias spp. were more specific. Orchids are commonly propagated without fungi using asymbiotic media. Asymbiotic and symbiotic methods were compared in two Eurasian terrestrial orchids in Chapter 4. In both cases, symbiotic methods resulted in higher germination and development. In Anacamptis laxiflora (Lam.) R. M. Bateman, Pridgeon & M. W. Chase, successful seedling establishment ex vitro was only achieved with symbiotic seedlings. Following this study, the effect of substrate rugosity and complexity on germination in asymbiotic and symbiotic culture of two Eurasian terrestrial orchids was investigated in Chapter 5. Substrate rugosity had a positive effect on germination and development in symbiotic cultures of A. morio and both asymbiotic and symbiotic cultures of Dactylorhiza purpurella (T.Stephenson & T.A.Stephenson) Soó. The subtribe Pleurothallidinae is one of the largest in the Orchidaceae and little is known about their propagation requirements. A number species from different genera within this group were tested with different asymbiotic media and fungi isolated from plants in an ex situ collection in Chapter 6. Germination was highest with two fungal strains but development of plantlets only occurred on asymbiotic media. Ex situ study and propagation of myco-heterotrophic orchids poses some difficulties. A novel method is presented, using microcosms for the initiation of tripartite symbioses with tree seedlings, fungi and orchids in Chapter 7. Associations between tree seedlings, fungi and orchid seed were observed. Germination was not achieved with seed of Neottia nidus-avis (L.) Rich. The method provides a basis for further development with applications in a range of ecological studies.

Three investigations are described in this dissertation, on the common theme of obtaining constitutive laws describing bulk properties of crystalline materials. We use 'first-principles' techniques where possible, an approach offering results which are predictive, with applicability to a wide class of materials, and with a systematic way to apply the techniques to any particular material of interest. We apply these techniques to silicon. The first investigation aims at developing an equation of state model for temperature dependent, anisotropic non-linear hyperelasticity. A method is presented for finding deformed states of a material on the same isentrope as a given starting configuration. The energies and stresses of a number of elastic deformations are sampled from dft molecular dynamics using this method, over a given range of the seven-dimensional space of deformation and potential temperature. The complete energy surface within this range can then be reliably reconstructed using the technique of Gaussian process regression. This is a machine learning technique that has particular merit here due to its ability to reconstruct a smooth surface without over-fitting. An equation of state model is then constructed for dft silicon, and demonstrated within a finite-volume continuum elasticity simulation for several problems of interest involving shock waves. The second investigation is concerned with the computation of properties of shock waves. We describe a simple annealing procedure to obtain the Hugoniot locus (states accessible by a shock wave) for a given material in a computationally efficient manner, particularly suited to first-principles calculations. We apply this method to determine the Hugoniot locus in bulk silicon from ab initio molecular dynamics with forces from density-functional theory, up to 70 GPa. In addition, we perform direct non-equilibrium molecular dynamics simulations of shock waves using empirical interatomic potentials and compare with our indirect method. We also present a direct ab initio molecular dynamics simulation of an elastic shock-wave in silicon, the first performed, to our knowledge. The third and final investigation is into the computation of thermal conductivity from atomistic simulations. We produce a number of model interatomic potentials for silicon, using the non-parametric, Bayesian approach of Gaussian Approximation Potentials, which are improved systematically through a database of training configurations. We compute the thermal conductivity from these at the level of the phonon-Boltzmann transport equation. The best of these potentials reproduces the dft value of phonon-Boltzmann conductivity to within a few percent, which is itself in good agreement with experiment. We consider several issues relating to computing thermal conductivity from molecular dynamics simulations.

This thesis is concerned with the analytic properties of arithmetic zeta functions, which remain largely conjectural at the time of writing. We will focus primarily on the most basic amongst them - meromorphic continuation and functional equation. Our weapon of choice is the so-called “mean-periodicity correspondence”, which provides a passage between nicely behaved arithmetic schemes and mean-periodic functions in certain functional spaces. In what follows, there are two major themes. 1. The comparison of the mean-periodicity properties of zeta functions with the much better known, but nonetheless conjectural, automorphicity properties of Hasse–Weil L functions. The latter of the two is a widely believed aspect of the Langlands program. In somewhat vague language, the two notions are dual to each other. One route to this result is broadly comparable to the Rankin-Selberg method, in which Fesenko’s “boundary function” plays the role of an Eisenstein series. 2. The use of a form of “lifted” harmonic analysis on the non-locally compact adele groups of arithmetic surfaces to develop integral representations of zeta functions. We also provide a more general discussion of a prospective theory of GL1(A(S)) zeta-integrals, where S is an arithmetic surface. When combined with adelic duality, we see that mean-periodicity may be accessible through further developments in higher dimensional adelic analysis. The results of the first flavour have some bearing on questions asked first by Langlands, and those of the second kind are an extension of the ideas of Tate for Hecke L-functions. The theorems proved here directly extend those of Fesenko and Suzuki on two-dimensional adelic analysis and the interplay between mean-periodicity and automorphicity.

The rise of indirectly elected institutions, such as the West Midlands Regional Assembly, has democratic implications for notions of accountability, legitimacy and representation. The representative function of these bodies must be explicitly fulfilled if they are to be considered democratic. The conceptual focus of this thesis is the representative function of members of the West Midlands Regional Assembly. The analysis applies a representative role framework based on Pitkin’s “Four Views of Representation” to explore the formalistic and substantive elements of representation through an appraisal of focus, style, role and scope. The results show that there are weak accountability structures in place, leading representatives to adopt a trustee conception of their roles. A grounded theory analysis is utilised to explore additional factors not covered in Pitkin’s framework. This surfaced the structural factors and role motivations that affect role choice. The thesis utilises Weick’s concept of sensemaking to explore the interpretation and enactment of different representative roles taking into account the importance of institutions in framing micro sensemaking processes. This new methodology permits an appraisal of the relative influence of institutional context, structure and individual agency and delivers a new model for understanding the logics of representative action in appointed bodies.

The evolution of species interactions is a fascinating subject, and one of vital importance if we are to understand how biological communities change over time. This thesis considers the interaction between aphids (Homoptera) and ants (Formicidae). Ants tend aphids for sugary honeydew and in return provide a variety of protective services. A literature review in Chapter 1 introduces the subject and provides background information. Chapter 2 considers ant- aphid interactions in a community setting. Specifically, I consider the fitness effects of the ant- aphid interaction on host plants. Net benefits or costs to plants depend on the densities of ants and aphids; these densities may themselves change depending on context dependent factors. Chapters 3 and 4 consider how semiochemicals can allow species to respectively maintain or avoid synchrony in space and time with mutualists or antagonists. Chapter 3 shows ladybirds avoid prey patches guarded by ants by reducing oviposition in response to ant semiochemicals. Chapter 4 shows that aphid walking dispersal can be limited by ant semiochemicals. This may be adaptive for aphids to remain in areas of enemy- free space. Alternatively, if levels of kin competition are high limited dispersal could be costly to aphids. In Chapter 5 I consider interactions between invasive and native ants. Ecological dominance in ants may be mediated by the ability to monopolise honeydew- producing resources. Chapter 6 explores ants’ decisions whether to tend or prey upon aphids. Predation of aphids depends on colony demand (e.g. through cues from the presence of larvae) as well as the quality or quantity of supply (e.g. increased predation of unproductive aphids). Finally, Chapter 7 deals with macroevolutionary patterns in the interaction between ants and aphids. Specifically, I identify ecological traits that characterise aphid- tending ants. A final discussion chapter summarises how ant-aphid interactions fit into existing mutualism theory.

This thesis is divided into three parts. Part one presents an overview of multi-component reactions, contrasting isocyanide based and non-isocyanide based multi-component reactions, and gives examples of the most important examples of these types of reactions. In addition, a brief discussion of 1,3-dipolar cycloadditions is given to serve as a framework for the discussion in part two of the results obtained. Part two is divided into three sections and discusses two conceptually different approaches to the development of new multi-component reactions. The first discusses the use of combinatorial methods for the generation and screening of reaction libraries and the limitations encountered in this approach. The second section deals with the use of isocyanides in a 1,4-cycloaddition followed by a 1,3-dipolar cycloaddition affording isoxazolines. A series of isocyanides were successfully employed both in an intra- and intermolecular fashion. Furthermore, the results gained from attempts using electron rich dipolarophiles as trapping agents in the latter 1,3-dipolar cycloaddition, suggest an alternative mechanism proceeding g through an intermediate nitronate, rather than the nitrile oxide as previously assumed. The initial low yields were improved upon by the use of lithium perchlorate as a promoter of the cycloaddition reaction. The third section details the attempts made at utilising silylated nucleophiles to generate silyinitronates from nitroalkenes and their subsequent use in inter- and intramolecular 1,3-dipolar cycloadditions. Part three describes the experimental procedures employed and results obtained.

In the Introduction, the development of theories about the prehistoric cultures of the Aegean, particularly the Mycenaean culture of the Greek mainland, is sketched. It is argued that the greatest deficiencies of all theories are that they have failed to take enough account of the culture preceding the Mycenaean, the Middle Helladic, and have too readily assumed that the mainland was a cultural unity in the Middle and Late Bronze Age. The intention of this thesis is to consider the remains from a chronological and regional point of view, in which the Middle Helladic culture, the Shaft Graves, and the evidence for Early Mycenaean development outside the Argolid will all be given separate treatment. The term 'Early Mycenaean' is defined as being the period from the adoption of Mycenaean culture to the horizon of destructions marked by Late Minoan IB pottery, equivalent to the pottery-phases Late Helladic I and IIA; the following period, to the fall of Knossos, is called 'Middle Mycenaean'. [continued in text ...]