Thesis (M.S. in civil engineering)--Washington State University, May 2010. / Title from PDF title page (viewed on July 21, 2010). "Department of Civil and Environmental Engineering." Includes bibliographical references (p. 96-97).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1981. / Typescript. Vita. Description based on print version record. Includes bibliographical references (leaves 326-342).

Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Includes bibliographical references (leaves 110-111). Also available on the Internet.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1981. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.

Protein-carbohydrate recognition is an important target for inhibitor development. Improved inhibitor design requires a fundamental molecular basis of these interactions. This thesis describes the preliminary structural studies on three carbohydrate processing enzymes, UDP-galactopyranose mutase, alpha-D-glucose-1-phosphate thymidylyltransferase and TDP-glucose 4,6-dehydratase. These enzymes are found in important human pathogens such as Mycobacterium tuberculosis and Salmonella typhimurium. The major focus of the thesis has been on UDP-galactopyranose mutase, the enzyme responsible for catalysing synthesis of the thermodynamically unfavourable 5 membered ring form of galactose, UDP-galactofuranose from the thermodynamically favoured 6 membered ring form, UDP-galactopyranose. UDP-galactofuranose plays a key role in mycobacterial cell walls. This thesis also describes work with concanavalin A. This legume lectin is an invaluable model for the study of protein-carbohydrate interactions. Two concanavalin A complexes are discussed. Both structures clear up misunderstandings in the literature and provide an insight into designing enzyme inhibitors.

Cells of S. marina (N.C.M.B, 778) were disrupted using a Hughes press and a purified cell wall fraction obtained using a previously reported method for halococcal wall isolation. This procedure was monitored by examination of thin sections in the electron microscope and the final wall preparation was seen to be relatively free of cytoplasmic and membranous contaminants. However, treatment of the wall fraction with crude trypsin did appear to remove particulate surface components. The total ninhydrin-positive components detectable accounted, for only about 14% of the cell wall dry weight. The major amino acids present were glycine, alanine, glutamic acid and aspartic acid although very small amounts of others were detected. The amino sugar components included glucosamine and galactosamine although these only accounted for some 60% of the total amino sugars. The remainder was probably made up of one or more of four unidentified, acid-labile components detected on amino acid analysis and by paper chromatography. This is in accord with the finding of unusual, labile amino sugars in the cell walls of other halococcal species. Approximately 37% of the cell wall dry weight was made up of the neutral sugars, glucose, galactose and mannose which were present in eguimolar amounts. In addition, the wall was found to contain a negligible lipid (0.1% dry weight) and a high ash (9.2% dry weight) content. The poor recovery of organic material after analysis is almost certainly due to the lability of some of the more unusual (and in this work unidentified) components. Attempts to selectively solubilise the wall material with a view to identifying discrete polymers met with some success. In Particular, treatment with trichloroacetic acid (TCA) at 35° extracted all of the glactosamine from the wall (in addition to other components) but none of the unknown component, X1. Further treatment with TCA at 60 extracted all of another unknown component, X1. These results suggest that some degree of resolution of different polymers constituting the wall may be possible and may have been achieved here. Treatment of S. marina with the antibiotics, D-cycloserine, novobiocin, bacitracin, penicillin G and vancomycin, known to affect cell wall biosynthesis in other bacteria, was carried out. Possible effects of the antibiotics were monitored by electron microscopy and turbidimetric estimation of bacterial growth. Only novobiocin and bacitracin had any effect on growth but this was marked; in both cases growth was prevented by addition of the antibiotic. The other three antibiotics all lost their antibiotic activity (against appropriate indicator organisms) when incubated over a period of a few hours in Dundas medium. It is suggested that this may be a significant consideration when explaining the antibiotic insensitivity of microorganisms, such as S. marina whose doubling times are of the same order of magnitude as that necessary for antibiotic inactivation. Thin sections of control and antibiotic-treated cells showed interesting ultrastructural features comparable with those seen in more conventional halophilic cocci. Some minor ultrastructural changes were seen in some of the anti-biotic-treated cells, the most notable being extensive plasmolysis in the case of novobiocin. However, none of the antibiotics tested appeared to cause cell lysis or osmotic fragility which may preclude their use as agents for the non-destructive removal of the cell wall.

In conventional wind tunnels the solid-wall or open-jet test section imposes on the flow field around the test model new boundary conditions absent in free air. Unless a small model is used, the solid-wall test section generally increases the loadings on the model while the open-jet boundary decreases the loadings compared to the unconfined case. However, the development of a low wall-interference test section and its successful demonstration would allow the testing of relatively large models without the application of often uncertain correction formulae. The Tolerant wind tunnel, which makes use of the opposite effects of solid and open boundaries, is a transversely slatted-wall test section designed to produce at an optimal wall open-area ratio (OAR) low-correction data for a wide variety of model shapes and sizes. Initially intended for low-speed airfoil testing, its use is theoretically and experimentally investigated here in connection with bluff body testing. A simple mathematical model based on two-dimensional potential flow theory and solved with the help of a vortex surface-singularity technique is used to estimate the best wall configuration. The theory predicts an optimum OAR of about 0.45 at which pressure distributions on flat plate and circular cylinder models of blockage ratios up to 33.3 % would differ from the free-air values by not more than 1 %. On the other hand, experiments performed with flat plate, circular cylinder and circular-cylinder-with-splitter-plate models indicate the existence of an optimum configuration around OAR = 0.6. The experiments also show a maximum allowable blockage in the Tolerant wind tunnel to be equivalent to the blockage created by a 33.3 %-blockage-ratio flat plate model. / Applied Science, Faculty of / Mechanical Engineering, Department of / Graduate

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