Some mounted ill. / Bibliography: leaves 147-194 / 194 leaves : / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (M.D.)--University of Adelaide, Dept. of Surgery, 1984

A major product of HIV-infected and cytokine-stimulated monocytic-lineage cells is quinolinic acid (QUIN), a neurotoxic metabolite of the kynurenine pathway (KP) of L-tryptophan (L-Trp) metabolism. Despite the large number of neurotoxins found in HIV patients with AIDS Dementia Complex (ADC), only QUIN correlates with both the presence and severity of ADC. With treatment, cerebrospinal fluid (CSF) QUIN concentrations decrease proportionate to the degree of clinical and neuropsychological improvement. As endothelial cells (EC) of the blood-brain barrier (BBB) are the first brain-associated cell that a bloodborne pathogen would encounter, this project examined the BBB response to KP metabolites, as these are implicated in damage of the CNS associated with ADC. Using RT-PCR and HPLC/gas chromatographymass spectrometry (GC-MS), I found that cultured primary human BBB EC and pericytes constitutively expressed the KP. EC synthesised kynurenic acid (KA) constitutively, and after immune activation, kynurenine (KYN). Pericytes produced small amounts of picolinic acid and after immune activation, KYN. An SV40-transformed BBB EC showed no KP expression. By contrast, human umbilical vein EC only expressed low levels of KA after immune activation, however human dermal microvascular EC showed a similar constitutive and inducible KP to that in BBB EC. As T cells are central to primary HIV infection, I also examined KP expression in two CD4+ and one CD4- cell lines, but none showed either constitutive or inducible KP expression. I next examined how QUIN might interact with BBB EC. There was no binding of 3H-QUIN to cultured primary human BBB EC, however a biologically relevant concentration of QUIN induced changes in gene expression which adversely affected EC function, possibly mediated by lipid peroxidation and oxidative stress. The upregulated genes were of the heat shock protein family, and the downregulated genes were associated with regulation of cell adhesion, tight junction and cytoskeletal stability, metalloproteinase (MMP) regulation, apoptosis and G protein signaling. Immunofluorescence showed that QUIN induced morphological changes in BBB EC consistent with the changes in gene expression. Gelatin zymography showed that this was not mediated by MMPs, as constitutive MMP expression was unchanged. These data provide strong evidence for QUIN directly damaging the BBB in the context of HIV infection.

A major product of HIV-infected and cytokine-stimulated monocytic-lineage cells is quinolinic acid (QUIN), a neurotoxic metabolite of the kynurenine pathway (KP) of L-tryptophan (L-Trp) metabolism. Despite the large number of neurotoxins found in HIV patients with AIDS Dementia Complex (ADC), only QUIN correlates with both the presence and severity of ADC. With treatment, cerebrospinal fluid (CSF) QUIN concentrations decrease proportionate to the degree of clinical and neuropsychological improvement. As endothelial cells (EC) of the blood-brain barrier (BBB) are the first brain-associated cell that a bloodborne pathogen would encounter, this project examined the BBB response to KP metabolites, as these are implicated in damage of the CNS associated with ADC. Using RT-PCR and HPLC/gas chromatographymass spectrometry (GC-MS), I found that cultured primary human BBB EC and pericytes constitutively expressed the KP. EC synthesised kynurenic acid (KA) constitutively, and after immune activation, kynurenine (KYN). Pericytes produced small amounts of picolinic acid and after immune activation, KYN. An SV40-transformed BBB EC showed no KP expression. By contrast, human umbilical vein EC only expressed low levels of KA after immune activation, however human dermal microvascular EC showed a similar constitutive and inducible KP to that in BBB EC. As T cells are central to primary HIV infection, I also examined KP expression in two CD4+ and one CD4- cell lines, but none showed either constitutive or inducible KP expression. I next examined how QUIN might interact with BBB EC. There was no binding of 3H-QUIN to cultured primary human BBB EC, however a biologically relevant concentration of QUIN induced changes in gene expression which adversely affected EC function, possibly mediated by lipid peroxidation and oxidative stress. The upregulated genes were of the heat shock protein family, and the downregulated genes were associated with regulation of cell adhesion, tight junction and cytoskeletal stability, metalloproteinase (MMP) regulation, apoptosis and G protein signaling. Immunofluorescence showed that QUIN induced morphological changes in BBB EC consistent with the changes in gene expression. Gelatin zymography showed that this was not mediated by MMPs, as constitutive MMP expression was unchanged. These data provide strong evidence for QUIN directly damaging the BBB in the context of HIV infection.

<p>This paper examines the pricing of barrier options using Monte Carlo Simulations. MATLAB based software is developed to estimate the price of the option using Monte Carlo simulation. We consider a generalized barrier option of knock out type, but we let the domain take the shape of a rectangular box. We investigate the price of this kind of barrier options. We investigate how the box is placed and what effect it will have on the price of the option. We compare the number of trajectories that are needed in order to achieve the same accuracy between this box barrier option and an ordinary option.</p>

<p>Tantalum diffusion barrier coatings were investigated as a way to improve the conversion efficiency of CIGS (copper indium gallium diselenide) solar cells.  Tantalum coatings were deposited upon silicon and stainless steel foil substrates using direct current magnetron sputtering (DcMS) and high power impulse magnetron sputtering (HiPIMS).  The coatings were characterized using scanning electron microscopy (SEM).  Cross-sectional scanning electron micrographs revealed that the HiPIMS coatings appeared denser than the DcMS coatings.</p>

The goal of this paper is to develop some computational experience and test the practical relevance of the theory of condition numbers C(d) for linear optimization, as applied to problem instances that one might encounter in practice. We used the NETLIB suite of linear optimization problems as a test bed for condition number computation and analysis. Our computational results indicate that 72% of the NETLIB suite problem instances are ill-conditioned. However, after pre-processing heuristics are applied, only 19% of the post-processed problem instances are ill-conditioned, and log C(d) of the finitely-conditioned post-processed problems is fairly nicely distributed. We also show that the number of IPM iterations needed to solve the problems in the NETLIB suite varies roughly linearly (and monotonically) with log C(d) of the post-processed problem instances. Empirical evidence yields a positive linear relationship between IPM iterations and log C(d) for the post-processed problem instances, significant at the 95% confidence level. Furthermore, 42% of the variation in IPM iterations among the NETLIB suite problem instances is accounted for by log C(d) of the problem instances after pre-processin

No description available.

Railway track and ground vibrations are considered, with anemphasis on methods of mitigation ("countermeasures"), forapplication to wayside disturbance problems. Original field measurements from two sites in Sweden, aswell as borrowed measurements from Norway, provide vibrationresults at many points on the track, on and underneath theground surface, for a variety of trains, both with and withoutcountermeasures in-place. Infinite periodic system theory is the basis of track-onlyand track-ground interaction models presented. The repeatingelement includes the sleeper, pad-fastener, rail, and either alocally-reacting ballast or a continuous ballast-soilwaveguide. The track-only model is even refined for nonlinearand high-frequency cases. The models are suitable for studyingcountermeasures in the track, or in the foundation(soil-stabilization). This latter countermeasure is shown to beeffective at low frequencies (of geotechnical interest), butsometimes counterproductive at audible frequencies (disturbanceproblems). An analytical model for hard seismic screens is alsopresented, to complement the treatment of ground vibrationcountermeasures; this is based on physical approximations whichare favored by "high" (i.e, audible)frequencies and softsoils. Notably, experimentally observed resonant behavior isexplained. <b>Keywords:</b>ground vibration, vibration screen, trackvibration, railway vibration

Tantalum diffusion barrier coatings were investigated as a way to improve the conversion efficiency of CIGS (copper indium gallium diselenide) solar cells.  Tantalum coatings were deposited upon silicon and stainless steel foil substrates using direct current magnetron sputtering (DcMS) and high power impulse magnetron sputtering (HiPIMS).  The coatings were characterized using scanning electron microscopy (SEM).  Cross-sectional scanning electron micrographs revealed that the HiPIMS coatings appeared denser than the DcMS coatings.

This paper examines the pricing of barrier options using Monte Carlo Simulations. MATLAB based software is developed to estimate the price of the option using Monte Carlo simulation. We consider a generalized barrier option of knock out type, but we let the domain take the shape of a rectangular box. We investigate the price of this kind of barrier options. We investigate how the box is placed and what effect it will have on the price of the option. We compare the number of trajectories that are needed in order to achieve the same accuracy between this box barrier option and an ordinary option.