Although a number of HSPs have been shown to be up-regulated in a wide range of human cancers, the full significance of this remains to be determined. The localisation of HSPs seems to be critical in determining their role in cancer cell survival; High intracellular levels (iHsp) appear to be advantageous to the tumour cell, inhibiting key steps in apoptosis, while in some circumstances, surface expression (sHsp) appears to be detrimental to the cell, aiding immune recognition by various effector cells. Consequently, clarifying the importance of HSP cellular location in the cancer setting may lead to the development of novel therapies based upon manipulation of HSP localisation. This thesis had two major aims; (1) to investigate the cellular localisation of HSPs in leukocytes from patients with both myelocytic and lymphocytic malignancies in order to establish relationships between apoptosis and stage of disease (2) to study the synergistic effect of four chemotherapeutic drugs with membrane fluidising agents, compounds which have the potential to modulate HSP localisation. Hsp90 and Hsp27 expression was shown to be restricted to the inside of peripheral blood leukocytes, while Hsp72 was localised both intracellularly and on the cell surface. In CLL, iHsp90 and iHsp27 levels were found to be significantly higher than in control subjects, while surface and intracellular Hsp72 was shown to be expressed either at very high levels or at very low levels. Furthermore, iHsp90 levels were found to be associated with stage of disease, while iHsp27 levels were shown to negatively correlate with levels of apoptosis. CLL patients with stable disease were found to express higher levels of iHsp72 than patients with progressive disease. However, in AML and MDS, levels of all HSPs in peripheral blood were found to be similar to those seen in control subjects, but disease patients showed a much wider range of expression. In AML, levels of sHsp72 positively correlated in all cell types, an observation not made in MDS patients or control subjects. HSP localisation was shown to be affected by membrane fluidising agents, with a movement of Hsp72 and Hsp60 to the cell surface. This effect was not due to proteotoxicity and supports data implicating the cell membrane in the regulation of HSP responses. This manipulation of HSP localisation and the increase in membrane fluidity resulted in increased sensitivity of CLL cells to three chemotherapeutic agents and points to the possibility that manipulation of membrane fluidity, may have significant value in the development of new treatment regimes.

In general, the objective of the present study was to incorporate some of the new psycho-biological approaches, with the theories propagating their use, in studying the phenomena of long-term memory in the goldfish.

A dissertation submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science in Engineering, 2017. / The cardinal aspects of supersonic and hypersonic propulsion intake design involve understanding the internal shock wave structures forming therein. A study was conducted to explore the effects of internal surface curvature and entry deflection angle on steady axisymmetric shock waves. Very little is known about these influences with only Curved Shock Theory, produced by M¨ older, providing analytical insight directly after a curved shock wave. The shock waves and accompanying flow fields which were generated were studied via experimental and numerical means. Radius normalised internal radii of curvature of 1, 1.5 and 2 with entry deflection angles of 0◦, 4◦ and 8◦ were investigated between a Mach number range of Mach 2.4 and 3.6. Experimental results were produced using a blow down supersonic wind tunnel facility and were captured via shadowgraph and schlieren flow visualisation techniques. The numerical simulations were validated using the experimental results. A self similar curved shock wave shape equation was presented with an empirical model which uses flow Mach number and internal radius of curvature in order to produce the resulting curved shock shape. Curved Shock Theory streamlines were used to try predict the internal surfaces that produced the curved shocks but results did not correlate. This was due to extreme streamline curvature curving the streamlines when the shock angle approached the Mach angle. Very good agreement was however found between the theoretical and numerical streamlines at lower curvatures. The higher the internal surface curvature and entry deflection angle, the greater the flow fields were impacted. Steeper characteristics formed as a result, curving the shock wave more noticeably. Both the internal surface curvature and entry deflection angle were found to have an effect on the trailing edge expansion fans which then altered the shape of downstream shock wave structures. The highest curvature models produced steady double reflection patterns due the flow being turned in onto itself by the imposed internal surface curvature. The effects of conical and curved internal surfaces were explored for additional insight into the presence of flow-normal curvature and the curving of the attached shock waves. / XL2018

A dissertation submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science in Engineering, 2017. / In traditional two-dimensional shock wave theory the reflection of a shock wave off a surface is treated as an adiabatic process and that the reflection surface is perfectly rigid and smooth with an inviscid flow of the fluid. In reality it has been found that these assumptions are not entirely accurate, and that although they are a good indication in the regular and irregular reflection domains of shock waves over the surface, viscous and thermal effects are present within the flow field. It has been experimentally shown that the transition of regular reflection to irregular reflection exceeds the theoretical limit, which is known as the von Neumann paradox. This paradox has largely been accounted for in the formation of a viscous boundary layer behind the reflected shock wave, based on numerous experimental and computational studies. However, the thermal effects in the reflection process have largely been neglected as the assumption of heat transfer between the post-shock wave gas and the reflection surfaces is assumed to be invalid. These thermal effects were investigated by testing materials with a varying range of thermal conductivities (1.13 to 401 W/mK) and similar surface roughness’s below the suggested limit for hydraulic smoothness. Each experiment placed two test pieces at the same incidence angle, symmetrically in the shock tube. This allowed flow properties to be exactly the same for the two materials being tested with a single plane shock wave. Test Mach numbers ranged from 1.2790 to 1.3986, with tests conducted at shock wave incidence angles of 36◦, 40◦, 60◦ and 70◦. This allowed both the regular and irregular reflection domains to be tested. Shadowgraph images were created using a z-configuration optical set up. These shadowgraph images were analysed quantitatively based on the angles measured as well as qualitatively based on flow features and symmetry. Both the quantitative and qualitative tests indicated that there was a difference in the angles between the reflected shock waves and surfaces based on the material thermal conductivity. In the quantitative tests the value of this angle was larger for materials with a lower thermal conductivity, and smaller for ones with a higher thermal conductivity for the regular reflection cases. In the irregular reflection cases the angle between the reflected and incident shock waves was larger for materials with a higher thermal conductivity. The materials with midrange thermal conductivities had reflection angles that lay within the bounds of the glass and copper angle values. The qualitative images supported these findings showing asymmetry in materials with different thermal conductivities with the intersection of reflected shock waves lying closer to the material with a higher thermal conductivity. Control experiments using test pieces made from an identical material showed no bias due to the location of the test piece in the shock tube / XL2018

The last stage of a deflagration-to-detonation transition (DDT) process involves the propagation and acceleration of a fast flame. This process is currently poorly understood. The difficulties lie in its complex structure, which is turbulent and involves multi-dimensional gasdynamic phenomena. Previous experimental studies have established these fast flames from the interaction of a detonation wave with a row of obstacles or porous plate. Two main questions remain unsolved: 1) What is the propagation speed of the fast flame obtained in these configurations and 2), Which factors dominate the occurrence of the DDT phenomenon? To answer these questions, two models have been constructed in the present work. Firstly, a quasi-1D gasdynamic model is proposed for estimating the transmitted reaction front speed and the strength of the transmitted shock. By alternately assuming a Chapman-Jouguet (CJ) deflagration or an inert shock, the model estimated the transmitted shock speeds. The comparison with extensive experimental data for a range of hydrocarbon fast flames revealed that the burning velocity required for transition to detonation was the CJ value. Secondly, a numerical shock-induced ignition model, which can impose mechanical fluctuations from a driven piston, was established in order to investigate the ignition and acceleration process, thereby clarifying the other question of interest. The results from the simulations indicated that the mechanical fluctuations can play an important role in triggering DDT by means of promoting the local ignition and amplification of the reaction front stemming from such ignition. It was also found that the maximum amplification effects occur with a fluctuation period between the non-fluctuated ignition delay and the time scale of chemical energy deposition. The inert simulation results show that two types of gasdynamic effects from the fluctuations were vital to the hot-spot formation. These hot spots make significant contribution to the detonation initiation.

Two aspects of detonation dynamics are addressed in this thesis by articles. The first part of the thesis investigates shock reflection phenomena believed to be responsible for enhancing reaction rates in detonations, namely Kelvin-Helmholtz instability and Mach stem bifurcation caused by forward jetting. Three papers are presented. The first numerically investigates shock reflections from a wedge under detonation-like conditions. A state of the art solver of the Euler equations is used. The shock reflection configuration is shown to depend on solver type, wedge implementation, and resolution. The type of reflection (i.e. regular or irregular) is found to depend on corner geometry, even far from the corner, showing initial conditions can play important roles in shock reflections. These complications are addressed with shock-resolved viscous simulations and a new initial condition: the triple point reflection. The numerical method is demonstrated in the second paper, and the presence of Kelvin-Helmholtz instability is investigated. Viscosity is found to play an important role in delaying the instability, which is found not to be a likely source of reaction acceleration on time scales commensurate with autoignition behind the Mach stem, but may become important on scales associated with the detonation cell. Mach stem bifurcations are investigated experimentally and numerically in the third paper. Experimental shock reflections are performed from a free-slip boundary in gases with differing isentropic exponents. Bifurcations are found in experiments, viscous and inviscid simulations. Viscosity is found to delay bifurcations. Inviscid simulations are used to approximate the limits of Mach stem bifurcation in the phase space of Mach number, isentropic exponent, and reflection angle. A maximum isentropic exponent is found beyond which bifurcations do not occur, matching the irregular/regular boundary of the detonation cellular structure. Flow field instability is found in experiments at high Mach number and low isentropic exponent. The second part of the thesis, comprised of one paper, investigates the dynamics of detonations with multiple thermicity peaks using Fickett's detonation analogue. Steady state analysis predicts multiple possible steady states, but only the fastest is singularity-free. Simulations show other solutions develop shock waves that eventually establish a detonation travelling at the fastest velocity allowed by the generalized Chapman-Jouguet criterion. Characteristic and linear stability analysis shows these shocks are found to arise due to instability at the sonic points.

by Wing-Hoi Tam. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 95-99). / Abstracts in English and Chinese. / Title --- p.1 / Acknowledgement --- p.2 / Contents --- p.3 / Abbreviations --- p.5 / List of figures --- p.7 / List of tables --- p.9 / Primers and their sequences used in the projcet --- p.10 / Abstract --- p.12 / Introduction / Small heat shock proteins --- p.16 / Human heart sequencing EST project --- p.17 / Small heat shock protein B3 (HSPB3) --- p.18 / The alpha crystallins --- p.18 / Point mutation of a conserved arginine in the alpha-crystallin domain perturbs the overall alpha crystallins structure and function --- p.19 / HSP27 Confers thermotolerance in cells --- p.19 / Chaperone properties of sHSP --- p.20 / In Viro-chaperone function of sHSPs --- p.21 / Does the alpha-crystallin domain necessary for chaperone activity? --- p.21 / Expression HSPB3 in heart diseases patients and in porcine model --- p.22 / Small heat shock proteins in development and differentiation --- p.23 / HSPB3 role in mammalian embryogenesis --- p.24 / Structure of the small heat shock proteins --- p.25 / Crystal structure of a small heat shock protein --- p.25 / Subunit contacts --- p.26 / Muscle is the only tissue that simultaneously expresses all five sHSPs --- p.26 / "Two independent sHSP systems in muscle cells, to serve and to protect" --- p.27 / Methods and Materials / Small scale preparation of plasmid DNA --- p.29 / Large scale preparation of plasmid DNA --- p.29 / Amplification of mouse and rat HSPB3 coding region --- p.30 / Northern Blotting and Hybridisation --- p.31 / Purification of DNA fragments by GENECLEAN --- p.31 / Preparation of competent Escherichia coli for transformation --- p.32 / Transformation of DNA plasmid into competent Escherichia coli --- p.32 / 5´ة Rapid Amplification of cDNA Ends (5´ةRACE) --- p.33 / 3´ة Rapid Amplification of cDNA Ends (3´ةRACE) --- p.35 / Upstream and Downstream Genomic sequence --- p.36 / Isolation of genomic DNA from human tissue --- p.37 / Multiple tissue cDNA panel (MTC) --- p.37 / The yeast two hybrid screenings and confirmation --- p.43 / Isolation of total RNA from human tissues --- p.43 / Automated Sequencing --- p.44 / Alignment of DNA and amino acid sequence --- p.44 / Radiation hybrid mapping --- p.45 / Results / Determination of the foll length of human HSPB3 cDNA by 5' and 3' RACE --- p.46 / Identification of human HSPB3 gene in mouse and rat heart tissues --- p.49 / "Sequence homology between human, mouse and rat HSPB3" --- p.51 / Chromosomal mapping of the HSPB3 gene --- p.60 / Expression of human HSPB3 is not confined to the heart and skeletal muscle --- p.62 / Mouse HSPB3 expression is confined to the heart tissue --- p.65 / HSPB3 genomic PCR of downstream sequence --- p.67 / HSPB3 upstream genomic sequence --- p.67 / No intronic sequences between the open reading frame --- p.68 / The yeast two hybrid screening --- p.71 / HSPB3 can not form dimers --- p.82 / Expression of Prepro-CDD-ANF in human adult and fetal --- p.83 / Discussions / Previously reported sequence HSPL27 is a chimera --- p.87 / HSPB3 monomers do not dimerises --- p.88 / No intronic sequence in the HSPB3 gene --- p.89 / HSPB3 and CDD-ANF may play an important role during stress to the heart --- p.91 / Change of expression pattern of Prepro-CDD-ANF during development --- p.93 / Reference --- p.95

Haemorrhagic shock (HS) is commonly associated with trauma. Severe haemorrhage causes hypoperfusion of tissues resulting in a global ischaemic state, and resuscitation is performed to restore circulating volume. However, the return of oxygen to ischaemic tissues causes the induction of a systemic inflammatory response, which contributes to cell death leading to organ failure. In trauma patients, failure of more than four organs is linked to certain mortality, highlighting the need for interventions that may reduce or prevent the deterioration in organ function. The aim of this thesis was to investigate the effect of therapeutic approaches on the organ injury and dysfunction induced by HS. Briefly, male Wistar rats were subjected to haemorrhage by withdrawal of blood to reduce the mean arterial pressure to 35 ± 5 mmHg for 90 min. Followed by resuscitation with 20 ml/kg Ringer’s lactate for 10 min and 50% of the shed blood for 50 min. Organ function was determined 4 h after the onset of resuscitation. This model was used to investigate the effect of three different interventions on the organ injury and dysfunction induced. In the first study, administration of bone marrow-derived mononuclear cells (BMMNCs) upon resuscitation resulted in (1) significant attenuation of the organ injury and dysfunction associated with HS, and (2) restoration of the activation of the Akt pro-survival pathway. It is possible that these beneficial effects are mediated by paracrine mediators secreted by BMMNCs, which modulate this pathway, however injection of large numbers of cells is not practical in the acute setting of trauma. Therefore, in the next study erythropoietin (EPO) was used as a daily pre-treatment for three days prior to the induction of haemorrhage, as EPO is a known stimulus of endothelial progenitor cell (EPC) mobilisation. EPO pre-treatment resulted in (1) significant attenuation of the organ injury and dysfunction associated with HS, (2) mobilisation of EPCs (CD34+/flk-1+), and (3) activation of the Akt pro-survival pathway with enhanced activation of eNOS. However, when used clinically EPO is associated with an increased risk of thrombotic events, therefore in the final study a non-erythropoietic analogue of EPO was investigated. Treatment with pyroglutamate helix B surface peptide (pHBSP) resulted in (1) significant attenuation of the organ injury and dysfunction associated with HS, and (2) activation of the Akt pro-survival pathway with enhanced activation of both eNOS and STAT3. Additionally, late pHBSP treatment, up to 60 min after the onset of resuscitation, exerted the highest degree of protection. The findings of this thesis support the view that modulation of the Akt pro-survival pathway is a potential therapeutic target in the treatment of the ischaemia-reperfusion injury associated with severe haemorrhage and resuscitation.

Digitized by Kansas Correctional Industries

No description available.