In the context of new π-donor molecules, extended tetrathiafulvalenes have been widely studies for their use as components of electronically conductive charge-transfer materials. In contrast with the planar π -systems, we have focused our attention on extended tetrathiafulvalenes containing a conjugated anthracenyl spacer (anthracenediylidene derivatives). These TTF derivatives adopt a saddle-shaped conformation in the neutral state and a drastic change of conformation occurs upon oxidation to the dication species. Our main objective was to investigate the molecular and supramolecular architecture of these compounds. At the molecular scale, we synthesised cyclophanes by bridging the preformed anthracene tetrathiafulvalene system and studied their redox properties and crystal packing. We developed the chemistry of anthracenediylidene derivatives in order to direct the supramolecular architecture by secondary interactions (hydrogen-bonding, π-π stacking). Finally, we also investigated the incorporation of anthracenediylidene units inside dendritic structures in order to study the highly charged species formed upon oxidation.

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This dissertation examines the Carnap-Quine debate on analyticity with the objective of identifying exactly what is at stake. Close scrutiny of Quine’s criticism of the definitions of analyticity reveals that most of his objections are convincing only if they are considered in relation to the definitions of analyticity in natural language. Carnap, however, defines analyticity in artificial languages. The dissertation also shows that Carnap can meet the objections to his definitions by using a perspective based within his own philosophy. After examining the presumptions of each party to the debate, the dissertation concludes that the disagreement between Carnap and Quine on the notion of analyticity is rooted in their different approaches to empiricism and that there is nothing said by either philosopher which proves that one approach has ultimate advantages over the other. It is thus impossible to identify a winner in the Carnap-Quine debate on analyticity. The process of arriving at this conclusion starts with a discussion in the first three chapters of Carnap’s philosophy followed by a critical and detailed discussion of his syntactical and semantical definitions of analyticity and the advantages and disadvantages of each. Chapter Four examines Quine’s objections to Carnap’s definitions of essential predication and shows that his objections do not undermine Carnap’s definitions of this notion in artificial languages. It also shows how vital providing a proper definition of essential predication in natural language is for Carnap’s philosophy and examines whether or not he is able to do so. Chapter Five analyzes Quine’s objections to Carnap’s definitions of logical truth and demonstrates that Carnap is able to respond to all of them when the discussion is situated within his philosophical system. Again, Quine’s objections to definitions of logical truth are meaningful only if they are considered in relation to natural language, which is not Carnap’s concern. The dissertation concludes by showing that both Carnap and Quine arrived at their conclusions with respect to the nature of logical sentences, based not on the arguments in their debate on analyticity, but on their philosophical considerations regarding the principle of empiricism: for Carnap, logical sentences are out of the realm of knowledge and independent of matters of fact whereas, for Quine, these are as empirical as other sentences. Nothing either says in their debate can convince the other to accept a different viewpoint.

The development of methods for site-selective derivatization of natural products to enable simultaneous arming and structure activity relationship (SAR) studies has shown great potential for the synthesis of pharmaceutical drug leads and cellular probes for mechanism of action studies. Herein, we describe a strategy to functionalize carboxylic acid and phenol containing natural products. This methodology relies on the in situ generation of diazoalkanes to form the corresponding carbonyl esters and phenolic ethers derived from natural products. We applied this process to several natural products, to begin demonstrating the utility of this methodology for the simultaneous arming and SAR studies of natural products. To expand our group’s nucleophile catalyzed aldol lactonization (NCAL) reaction for synthesizing highly substituted cyclopentane fused beta-lactones, we developed a nucleophile catalyzed, tandem Michael aldol lactonization (NCMAL) reaction. Herein, we show the synthetic utility of this reaction in varying the Michael donors and acceptors, developing a catalytic, enantioselective NCMAL, and synthesizing tricyclic-!-lactones. Furthermore, we initiated studies toward applying this new methodology to the synthesis of a lipase inhibitor, vibralactone.

With increasing demands in bone repair and replacement, this research investigates the microstructure, properties and performance of bovine bone, human bone, and synthetic materials. Doing so, experimental approaches were used to exam and compare bones, as well as mimicking nature by developing a synthetic material to repair bones. Experimentally, bovine bone, tumor-free human bone, and cancerous human bone were studied via the small scale mechanical loading test. Failure analysis was conducted via optical and electronic microscopic techniques. Characterization results were used to develop a synthetic material that possesses strength and strain needed as a bone material. Characterizing techniques include a small punch test, scanning electron microscope (SEM), optical microscope and x-ray diffraction (XRD) were used for experimental approach. The results showed that small punch tests in longitudinal and tangential directions showed different mechanical properties and failure mechanisms. Cancer cells in human bone caused the bone softening and lowered the density. Synthesized epoxy-silicone-geopolymer material had higher deformability than bone. Understanding obtained in this research helps us to develop better synthetic bone materials in future. This thesis is composed of six chapters. The first chapter covers as an introduction to understand the purpose and motivation of present studies, and this section followed by the details of the motivation and objectives of this research. The third chapter explains experimental approaches that were conducted to meet the objectives. The fourth chapter describes the results and the major discovery of the experiments, and the results will be discussed in the Chapter IV. Finally, the last chapter provides the conclusions and recommendations for future work.

<p>Both light-cured (LC) and chemically-cured (CC) acrylic resin custom tray materials are used at the Oral Health Centre, Faculty of Dentistry, University of the Western Cape. At present, the CC acrylic is the standard for formal undergraduate teaching and training. The LC material is not part of routine didactic teaching as little evidence-based scientific information is available with regards to its properties and its usage in the clinical environment. Negative effects have caused researchers to focus on alternatives and to research for other materials with more advantageous properties. The objectives of this study was to determine the linear dimensional shrinkage and fracture toughness of light-cured acrylic custom tray materials and compare it to the chemically-cured type. Also to evaluate the acceptance of light-cured acrylic resin custom trays by undergraduate students.</p>

Typescript. / Bibliography: p. 199-208. / xxv, 208 p. : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Electrical and Electronic Engineering, 1997

Thesis (Ph. D.)--University of Canterbury, 2007. / Typescript (photocopy). "January 2007." Includes bibliographical references (p. [209]-223). Also available via the World Wide Web.

Thesis (Ph. D. - Soil, Water and Environmental Science)--University of Arizona, 1997. / Includes bibliographical references (leaves 105-108).

Thesis (Ph.D.) -- University of Adelaide, Dept. of Electrical and Electronic Engineering, 2000. / Table of corrections inserted opposite table of contents. Bibliography: p.191-212.