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This body of work is based upon the following three papers that the author wrote during his PhD with Jonathan Fraser and Han Yu: [FH20, HY17, How19]. Chapter 1 starts by introducing many of the common tools and notation that will be used throughout this thesis. This will cover the main notions of dimensions discussed from both the set and the measure perspectives. An emphasis will be placed on their relationships where possible. This will provide a solid base upon which to expand. Many of the standard results in this part can be found in fractal geometry textbooks such as [Fal03, Mat95] if further reading was desired. The first results discussed in Chapter 2 will cover some of the regularity dimensions' properties such as general bounds in relation to the Assouad and lower dimensions, local dimensions and the Lq-spectrum. The Assoaud and lower dimensions are known to interact pleasantly with weak tangents and these ideas are discussed in the regularity dimension setting. We then calculate the regularity dimensions for several specific example measures such as self-similar and self-affine measures which provides an opportunity to discuss the sharpness of the previously obtained bounds. This work originates in [FH20] where the upper regularity dimension was studied, with many of the lower regularity dimension results being natural extensions. In Chapter 3 we continue the study of the upper and lower regularity dimensions with an emphasis on how they can be used to quantify doubling and uniform perfectness of measures. This starts with an explicit relation between the upper regularity dimension and the doubling constants along with a similar link between the lower regularity dimension and the constants of uniform perfectness. We then turn our attention to a technical result which can be made more quantitative thanks to the regularity dimensions. It is interesting to study how properties, such as doubling, change under pushforwards by different types of maps, here we study the regularity dimensions of pushforward measures with respect to quasisymmetric homeomorphisms. We round this chapter out with an interesting application of the lower regularity to Diophantine approximation by noting the equivalence between uniform perfectness and weakly absolutely α-decaying measures. The original material for this part can be found in [How19] with part of the first section integrating a result of [FH20]. Finally, in Chapter 4, we will consider graphs of Brownian motion, and more generally, graphs of Levy processes. This will involve the calculation of the lower and Assouad dimensions for such sets and then the regularity dimensions of measures pushed onto these graphs from the real line. These graphs are the only examples in this thesis for which the Assouad and lower dimensions had not been previously calculated so we delve deeper into the area, studying graphs of functions defined as stochastic integrals as well. This chapter is based on the paper [HY17] for the set theoretic half, with the regularity dimension results coming from [How19].

Attenuated total reflection Fourier transform infrared (FTIR) spectroscopy in the 4000-800 cm"1 range was applied to NADH:ubiquinone oxidoreductase (complex I) and cytochrome bc complex of the respiratory electron transfer chain. High signal:noise redox difference spectra were acquired using novel electrochemical and perfusion techniques to reversibly adjust protein redox state which, where appropriate, was monitored by simultaneous UV/visible spectroscopy. Interpretation of spectra was assisted by hydrogen-deuterium exchange, 15N labelling and redox titration. Model compound data, including protonation state/redox difference spectra of histidine, flavin mononucleotide and ferredoxins, were recorded and are presented as a comprehensive 'toolkit' for assisting in acquisition and interpretation of protein IR data in general. Electrochemically-induced difference spectra of bovine and Rhodobacter capsulatus cytochrome bc complex are comparable to published perfusion data but are at significantly higher signahnoise demonstrating the functionality of the electrochemical technique. Comparison of wild-type and E295V Rba. capsulatus difference spectra resulting from haem reduction/oxidation definitively rules out Glu-295 as the principal carboxylic acid residue responsive to haem b redox change. Full redox difference spectra of Yarrowia lipolytica and bovine complex I are similar to published E. coli transmission FTIR spectra where signals in the amide I and II region were interpreted as indictors of large scale conformational change. Comparison of complex I and ferredoxin difference spectra rules out this interpretation. Signals in the presented spectra are tentatively assigned to reduced flavin and to protonation state change of one or more histidine residues. In iron-sulphur centre N2 redox difference spectra, measured in intact complex I for the first time, signals from substrate ubiquinone/ubiquinol formation are clear a putative histidine protonation change signal is also present. Perfusion induced-difference spectra, using NADH as reductant, indicate that NADH does not reduce the full complement of iron-sulphur centres and no signals indicative of large scale conformational change were present.

This thesis is concerned with evaluating postage stamps as social agents, using Japan as a case study. For the period 1937-1988 it identifies various messages about Japanese identity implied by the symbolism used by Japanese Governments in their postage stamp designs and by their choice of special issues. It explores the extent to which those messages have been received by both Japanese and British collectors of these stamps and the reasons why their communication has been found to be largely ineffective. The study identifies the tendency of stamp users to appreciate stamps aesthetically, as art objects, rather than as symbols and the practices of stamp collecting as the major obstacles to the recognition of their symbolic messages. The view that stamp collecting is a social practice which is defined by the cultural traditions of the collectors' societies is questioned. Evidence is offered for the 'globalisation' of this form of collecting and for the evolution of postage stamps from being utility items largely confined to their issuing societies into 'collectibles' designed for a global market. The implications of: Governments' acceptance of this change in postage stamps' status; the moves to privatise postal services; and the availability of new technology, both for Governments' continued use of stamps as 'little diplomats' and for theories of collecting are shown to need further study. My thesis suggests that the social agency of postage stamps has been more effective in helping to establish the self-identity of their collectors as collectors rather than in giving those collectors insight into the identities of the countries issuing them and that the social agency of material objects is determined more by their users than by their producers.

Evidence from clinical and animal studies indicates an interaction between cancer and the haemostatic system. Human malignancy disrupts the normal haemostatic balance in favour of a hypercoagulable state while studies on the effects of anticoagulant/antiplatelet agents in animal models of metastasis indicate a role for coagulation in the metastatic process. Recent work has demonstrated that Streptokinase inhibits pulmonary tumour seeding in an animal model of metastasising breast carcinoma. The purpose of the first half of this thesis was to investigate the mechanism of pulmonary tumour inhibition by Streptokinase. Validation of the experimental tumour model was first performed to confirm the dose, time of administration and effect of Streptokinase on pulmonary tumour seeding. The results of these experiments confirmed that the inhibitory effect of Streptokinase on pulmonary tumour nodule formation was reproducible. It was hypothesised that the effect of tumour inhibition by Streptokinase was secondary to dissolution of the fibrin clot surrounding tumour cells entrapped within the pulmonary microcirculation. In order to confirm fibrin clot lysis, a study was undertaken to measure fibrinolytic activity during Streptokinase treatment by estimation of plasma fibrin degradation product levels (FDP). The results showed a tendency to increased FDP levels in animals receiving Streptokinase although this failed to reach statistical significance possibly due to the low level fibrinolytic activity exhibited by untreated controls. In order to provide conclusive evidence that the antitumour effect of Streptokinase was due to fibrin clot breakdown, a further study was performed to compare the effect of Streptokinase and a second fibrinolytic agent, human recombinant tissue Plasminogen Activator (rt-PA), on pulmonary tumour seeding. The results showed a comparable twofold reduction in pulmonary tumour seeding by both these fibrinolytic agents. The demonstration that two structurally distinct compounds, unrelated except for their ability to induce fibrin clot lysis, produce a similar antitumour effect, suggests that this effect is likely to be secondary to fibrin clot lysis. Platelets are also an integral component of thrombi surrounding tumour cells arrested in the microvasculature. Further animal studies were therefore performed to establish whether a dual assault on fibrin clot formation and platelet deposition had an additive inhibitory effect on pulmonary tumour seeding. Since tumour cell-induced platelet activation may occur via a number of pathways including the generation of thrombin and activation by ADP, this study used two antiplatelet agents with separate mechanisms of action. Although there was a trend towards inhibition of pulmonary tumour seeding with aspirin, this failed to reach a significant level suggesting that platelet activation by the Mtln3 cell line may be independent of the cyclo-oxygenase pathway. In contrast, ticlopidine significantly inhibited pulmonary tumour seeding suggesting that tumour cell-induced platelet aggregation by the Mtln3 cell line may be dependent on the generation of ADP. The combination of ticlopidine and Streptokinase on inhibition of pulmonary tumour seeding was no more effective than Streptokinase treatment alone indicating that in this animal model, fibrin may play a more important role than platelets in the intravascular phase of the metastatic process. These animal studies suggest that fibrinolytic therapy may have a role in reducing metastatic progression in patients with malignant disease. The second half of this thesis was designed to identify cancer patients who might benefit from such antimetastatic therapy. Animal studies have demonstrated that manipulation of a primary tumour facilitates tumour cell dissemination via the bloodstream and may promote metastasis. Surgery and anaesthesia may further enhance the metastatic potential of circulating tumour cells shed during operative manipulation by inducing a state of relative immune suppression and facilitating tumour cell seeding in target organs in a more fertile, hypercoagulable blood environment. Fibrinolytic therapy is most likely to be effective if administered during such tumour cell dissemination. The studies of Turnbull using the "notouch" isolation technique in patients with colon 6 cancer have provided the only clinical evidence that surgical manipulation of primary tumours may facilitate metastasis. Evidence of intra-operative tumour cell dissemination might indicate a role for peri-operative antimetastatic therapy. It was therefore hypothesised that surgical manipulation during resection of a primary malignant tumour enhanced metastasis by facilitating tumour cell shedding into the bloodstream. Initial studies using two colour flow cytometry to detect circulating tumour cells in patients with breast cancer during surgery were unsuccessful due to inadequate sensitivity at low tumour cell concentrations.