Orientador: Carlos Henrique Inacio Ramos / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-13T20:53:19Z (GMT). No. of bitstreams: 1 Cagliari_ThiagoCarlos_D.pdf: 4482929 bytes, checksum: a1439ac0cca9a21c77eb47d2e163c224 (MD5) Previous issue date: 2009 / Resumo: As proteinas sao macromoleculas que possuem importancia vital para o funcionamento celular, participando da maioria das reacoes biologicas e tambem como componentes estruturais. Para que uma proteina possa exercer sua funcao, precisa atingir sua estrutura nativa atraves de um processo denominado enovelamento proteico. Neste contexto, as chaperonas moleculares sao proteinas capazes de auxiliar no enovelamento de outras proteinas, atuando na prevencao de agregados, desagregacao, translocacao, ativacao, entre outros. Dentre os muitos tipos de chaperonas existentes, neste trabalho foram abordadas as chaperonas das familias Hsp100 e Hsp90, as quais estao relacionadas aos processos de desagregacao e auxilio do enovelamento de proteinas-substrato, respectivamente. O presente trabalho pretendeu produzir as proteinas recombinantes Hsp100 e Hsp82 de cana-de-acucar para a caracterizacao de suas respectivas relacoes estrutura-funcao. Para isto foram empregadas tecnicas como: dicroismo circular, fluorescencia, espalhamento dinamico de luz e ultracentrifugacao analitica. Assim, foi observado que a forca ionica do meio e capaz de influenciar a estrutura quaternaria da proteina Hsp100, a qual se apresenta hexamerica em menores concentracoes de sal. Alem disto, e capaz de reconhecer agregados proteicos formados pelas proteinas luciferase e citrato sintase em ensaios in vitro. Ja a proteina Hsp82 apresentou uma estrutura dimerica, a qual nao e influenciada pela presenca de nucleotideos e apresenta grande estabilidade termica. Finalmente, a proteina p23 humana, a qual e responsavel por auxiliar a proteina Hsp90 no enovelamento de muitas proteinas/complexos proteicos, tambem foi caracterizada. Foram observados indicios de que a regiao C-terminal, rica em residuos de aminoacidos carregados, pode possuir algum grau de estruturacao, apesar de alguns estudos na literatura indicarem o contrario. O estudo das chaperonas de cana-de-acucar foi direcionado por um trabalho previo de anotacao de sequencias relacionadas as chaperonas moleculares no banco de dados do projeto SUCEST (Sugarcane EST Genome Project), o qual foi realizado por nosso grupo de pesquisa. Alem disto, sao apresentados os resultados da anotacao das sequencias relacionadas as chaperonas de eucalipto no banco de dados FORESTs (Eucalyptus Genome Sequencing Project Consortium), possibilitando futuros estudos com estas proteinas. / Abstract: Proteins are macromolecules that are vital to the functioning cell, participating in most of the biological reactions as well as structural components. To perform its function, a protein need to achieve its native structure through a process called protein folding. In this context, the molecular chaperone proteins are able to assist in the folding of other proteins, acting in the prevention of aggregation, disaggregation, translocation, activation, among others. From all types of existing chaperones, here were highlight the Hsp100 and Hsp90 families, which are related to processes of disaggregation and assistance of substrateprotein folding, respectively. This study sought to produce the recombinant proteins Hsp100 and Hsp82 from sugar cane for the characterization of their structure-function relationships. In order to do this, some techniques were employed such as: circular dichroism, fluorescence, dynamic light scattering and analytical ultracentrifugation. As a result, it was observed that the ionic strength of the solvent is capable of influencing the quaternary structure of protein Hsp100, which presents as a hexamer in lower salt concentrations. Furthermore, it is capable of recognizing protein aggregates formed by luciferase protein and citrate synthase in in vitro essays. The Hsp82 protein showed a dimeric structure, which was not influenced by the presence of nucleotides and presented a great thermal stability. Finally, the human protein p23, which is responsible for assisting in the Hsp90 protein folding of many proteins/protein complexes, was also characterized. In spite of some studies indicating the contrary, we observed evidence that the C-terminal region, which is rich in charged amino acid residues, can possible have some structure. The sugarcane chaperones study was guided by a previous chaperone sequence annotation work in the SUCEST (Sugarcane EST Genome Project) databank performed by our research group. In addition, results regarding chaperone sequences annotation in the eucalyptus databank (FORESTs - Eucalyptus Genome Sequencing Project Consortium) were presented here as well, which can also lead to future chaperone proteins function and structure studies. / Doutorado

Sepsis remains a severe issue in critically ill patients. Adjunctive therapies might play important role to decrease morbidity and mortality. The aim of this thesis is to investigate new adjunctive therapies role in the treatment of sepsis and septic shock. / Doctorat en Sciences biomédicales et pharmaceutiques / info:eu-repo/semantics/nonPublished

Historically, the endeavor of scale testing flight vehicles at supersonic Mach numbers, especially for long durations, has required the development of closed-loop wind tunnels, which are extremely expensive both to build and operate due to the high complexity and incredible power required to drive such a system. The intermittent blowdown wind tunnel, indraft tunnel, and shock tunnel have alleviated many of these cost requirements to some degree, whilst facilitating testing at very high Mach numbers and enthalpies; however, these systems require the handling of gases at pressures and temperatures that can be prohibitive for many university settings. The Ludwieg tube provides a simple, elegant method for producing testable supersonic flows at price points significantly lower than the aforementioned test-system architectures. Unfortunately, the spacial footprint and moderate cost required for driver tube and nozzle hardware can make it difficult to implement for many non-research universities. In this thesis, a new supersonic test system architecture is conceived, designed, implemented, and validated for the purpose of making supersonic aerodynamic testing capability attainable for most universities, by combining properties of the Ludwieg Tube and indraft wind tunnel to reduce the cost needed to produce this capability. This system, the Indraft Tube Tunnel, requires no long driver-tube or test-section hardware, aside from a vacuum chamber. Furthermore, it is safe to operate, as high pressure containment systems are not required for the Indraft Tube Tunnel System. It is designed and operated to draw stagnant atmospheric air through a converging-diverging nozzle to achieve a steady-state Mach number of 2.5. Sufficient pressure ratio to reach the desired Mach number is attained by evacuating the vacuum chamber and placing a thin cellophane diaphragm across the inlet of the nozzle, thus separating the vacuum section from ambient atmosphere. To initiate gas flow, the diaphragm is mechanically burst with a puncture device. This design requires much less hardware to implement than a typical Ludwieg tube, and had an operating cost of less than one dollar per test. Using this method, steady, uninterrupted Mach 2.44 is attained for a duration of 13.6 ms and a test section diameter of 7 inches. The standard deviation of the Mach number measurements is .08 Mach. A shadowgraph imaging setup is used to view and measure the angle of oblique shockwaves on a simple wedge test-model. The Indraft Tube Tunnel is novel in the field of high-speed aerodynamic testing, and may be implemented by other universities to produce supersonic flows with a relatively small investment in hardware and laboratory space.

This Diploma thesis deals with the design of device for measurement of vehicle shock absorbers. It describes shock absorbers and options for their diagnostics. In the next part describes design of device, strength analysis, modal analysis, and cost estimate. Transferring torque of device is realized by scotch yoke mechanism.

This thesis was made together with Syntronic, a leading design house specializing in advanced productand systems development. One of the major trends in vehicle industry today is the emergence of electricvehicles. One of the main challenges for the electric vehicles is the energy storage capacity whichtogether with powertrain, rolling- and wind resistance losses determines the vehicle range. Therefore,steps are taken in all areas from more efficient electronics to regenerative breaking which have beenwidely adopted, and the hunt for harvesting energy from other areas of the car is on its way. Energydissipated in heat from the shock absorbers can be harvested and some concepts of this have showngood results.The focus of this work was therefore to, based on previous studies, develop and evaluatea new type of shock absorber with integrated energy harvesting.A product development process was used to generate a new or develop a current concept for aregenerative shock absorber. From the product development process a compact hydraulic-electricsystem within the shock absorber were designed and evaluated on its regenerative capabilities with apeak efficiency of 32 percent while also providing an adjustable dampening coefficient. The conceptoffers a compact and affordable design by utilizing a vane pump integrated into the shock absorberpiston.

Shock waves have been used in medicine for more than 30 year. At the beginning was mainly use for lithotripsy, but today is also applied in other fields of medicine, such as orthopedics, rheumatology and others. Single shock wave is one shock that usually is repeated every 1-1.5 seconds. By contrast tandem shock waves are two shocks consecutively (ideal interval between shocks is from 8 to 15 microseconds), that are repeated. In this work we investigated the clinical use of single and tandem shock waves that are generated entirely new source. It is based on the principle of multichannel discharge. It was found that a single shock wave can destroy the union between bone and bone cement, this effect could be used in orthopedics. Single and tandem shock wave can damage the tumor in vivo, but the principle damage is different. Tandem shockwave is able to cause damage in a depth of acoustically homogeneous medium and enhances the effect of chemotherapy. It would therefore be possible to used single and tandem shock waves in oncology either alone, or their combination with other chemicals. Functional sample of clinically usable applicator of shock waves with a new source was made for these applications. Powered by TCPDF (www.tcpdf.org)

Indiana University-Purdue University Indianapolis (IUPUI) / The function of major histocompatability complex (MHC) class II molecules is to present antigenic peptides to CD4+ T cells. Typically, MHC class II molecules present peptides derived from exogenous sources. Yet, certain endogenous antigens (Ags) have been found to be presented by class II molecules. Studies suggest that specific heat shock protein family members may play a role in Ag processing and subsequent class II presentation. The studies presented here using B lymphoblasts demonstrate the importance of HSP90α, HSP90β, and possibly HSP70 in selectively regulating MHC class II presentation. Inactivation of HSP90 function using pharmacological inhibitors inhibited class II presentation of exogenous and endogenous GAD, but did not perturb the presentation of several other intra- and extracellular Ags. Individual knockdown of HSP90 isoforms using isoform specific siRNA selectively inhibited GAD Ag presentation. These results demonstrate a requirement for HSP90α and HSP90β in regulating MHC class II presentation of select Ags. Studies to explore mechanistically the roles of HSP90α and HSP90β in regulating GAD Ag presentation were pursued. The pathways of exogenous and endogenous MHC class II presentation of GAD Ag are distinct yet converge with shared terminal processing of GAD within endosomal/lysosomal vesicles. The effect of HSP90 manipulation on various shared components of the MHC class II pathway was examined. The studies presented here suggest that HSP90α and HSP90β regulate MHC class II presentation of GAD Ag at discrete steps most likely involving HSP90 binding to GAD Ag rather than perturbing overall MHC class II function. vi Studying the role of HSP90 in MHC class II presentation in B cells revealed the potential requirement for HSP70 in the presentation of select Ags. The studies presented here demonstrate a possible role for HSP70 in the presentation of Ags such as SMA or Ig kappa by MHC class II molecules. Also included in this work is a study of a rare case of diabetes caused by type B insulin resistance due to development of insulin receptor autoantibodies during the treatment of hepatitis C with interferon alpha and ribavirin. Clinical and laboratory findings in the case are presented.

An axi-symmetric shock-tube model has been developed to simulate the shock-wave propagation and reflection in both non-reactive and reactive flows. Simulations were performed for the full shock-tube geometry of the high-pressure shock tube facility at Texas A&M University. Computations were carried out in the CFD solver FLUENT based on the finite volume approach and the AUSM+ flux differencing scheme. Adaptive mesh refinement (AMR) algorithm was applied to the time-dependent flow fields to accurately capture and resolve the shock and contact discontinuities as well as the very fine scales associated with the viscous and reactive effects. A conjugate heat transfer model has been incorporated which enhanced the credibility of the simulations. The multi-dimensional, time-dependent numerical simulations resolved all of the relevant scales, ranging from the size of the system to the reaction zone scale. The robustness of the numerical model and the accuracy of the simulations were assessed through validation with the analytical ideal shock-tube theory and experimental data. The numerical method is first applied to the problem of axi-symmetric inviscid flow then viscous effects are incorporated through viscous modeling. The non-idealities in the shock tube have been investigated and quantified, notably the non-ideal transient behavior in the shock tube nozzle section, heat transfer effects from the hot gas to the shock tube side walls, the reflected shock/boundary layer interactions or what is known as bifurcation, and the contact surface/bifurcation interaction resulting into driver gas contamination. The non-reactive model is shown to be capable of accurately simulating the shock and expansion wave propagations and reflections as well as the flow non-uniformities behind the reflected shock wave. Both the inviscid and the viscous non-reactive models provided a baseline for the combustion model iii which involves elementary chemical reactions and requires the coupling of the chemistry with the flow fields adding to the complexity of the problem and thereby requiring tremendous computational resources. Combustion modeling focuses on the ignition process behind the reflected shock wave in undiluted and diluted Hydrogen test gas mixtures. Accurate representation of the Shock - tube reactive flow fields is more likely to be achieved by the means of the LES model in conjunction with the EDC model. The shock-tube CFD model developed herein provides valuable information to the interpretation of the shock-tube experimental data and to the understanding of the impact the facility-dependent non-idealities can have on the ignition delay time measurements.

Characterization of the dynamic behavior of defect-bearing ablator materials subjected to extreme conditions is essential in advancing fusion energy as an reliable and abundant energy source. By understanding how materials evolve spatially and temporally we can minimize hydrodynamic instabilities, which are major contributing factors to energy yield degradation in inertial confinement fusion (ICF) experiments. In this thesis we demonstrate the capabilities of an ultrafast x-ray imaging (UXI) detector, the Icarus V2, where we capture multiple frames of single void-bearing sample compressed by a high-intensity laser shockwave. Using the Matter in Extreme Conditions (MEC) instrument at the Linac Coherent Light Source (LCLS), we conducted two experiments with the x-ray free electron laser (XFEL) multi-pulse mode, delivering four nanosecond-separated pulses to a sample impacted by a laser shockwave, obtaining multiframe images of a single sample in the holographic and direct imaging regime with the UXI detector. In contrast to the low temporal resolution provided by current cameras, the Icarus V2 can capture images with high temporal resolution, which can be used to determine the mechanisms that prevent thermonuclear ignition in ICF experiments. For images captured in the holographic regime at our XFEL energy of 8.23 keV, we realized that the shock front was obscured by strong phase-contrast effects. We recognized that by increasing the XFEL energy while in the holographic regime, more distinguishable features could be revealed behind and along the shock front. Alternatively, in the direct-imaging configuration we discovered that the evolution of microstructural features were directly recognizable in comparison to the holographic regime at lower XFEL energies. Overall, the images captured by the UXI in both regimes demonstrated our ability to obtain multiframe images of processes that occur over several nanoseconds for single samples, which has never been done before. Moreover, the capabilities of the UXI enable extraction of quantitative information over multiple frames, which can help with uncovering the underlying physics involved in high energy density (HED) physics experiments and other experiments involving non-repeatable ultrafast phenomena. Specifically, insight into the behavior of the void can be gained by performing phase retrieval on the images and obtaining the areal density of the materials during laser-shock ablation. Generally, the UXI improves data acquisition speed and operational efficiency, which extends this camera's functionality to experiments that occur at various time scales or experiments that require multiple images to be captured.

The re-entry space vehicles encounter high temperatures when they enter the earth atmosphere and the high temperature air in the shock layer around the body undergoes partial dissociation. Also, the gas molecules injected into the shock layer from the ablative thermal protection system (TPS) undergo pyrolysis which helps in reducing the net heat flux to the vehicle surface. The chemical species due to the pyrolysis add complexity to the stagnation flow chemistry (52 chemical reactions) models which include species like NOx, CO and hydrocarbons (HCs). Although the ablative TPS is responsible for the safety of re-entry space vehicle, the induced chemical species result in variety of adverse effects on environment such as global warming, acid rain, green house effect etc. The well known three-way-catalyst (TWC) involves simultaneous removal of all the three gases (i.e, NOx, CO, Hydrocarbons) present in the shock layer. Interaction of such three-way-catalyst on the heat shield materials or on the wall of the re-entry space vehicle is to reduce the heat flux and to remove the gases in the shock layer, which is an important issue. For the re-entry vehicle the maximum aerodynamic heating occurs at an altitude ranging about 68 to 45 km during which the vehicle is surrounded by high temperature dissociated air. Then the simplest real gas model of air is the five species model which is based on N2, O2, O, NO and N. This five species model assumes no ionization and no pyrolysis gases are emitted from the heat shield materials. The experimental research work presented in this thesis is directed towards the understanding of catalytic and non-catalytic surface reactions on high temperature materials in presence of strong shock heated test gas. We have also explored the possibility of using shock tube as a high enthalpy device for synthesis of new materials. In the first Chapter, we have presented an overview of re-entry space vehicles, thermal protection system (TPS) and importance of real gas effects in the shock layer. Literature survey on TPS, ablative materials and aerothermochemistry at the stagnation point of reentry capsule, in addition to catalytic and non-catalytic surface reactions between the wall and dissociated air in the shock layer are presented. In Chapters 2 and 3, we present the experimental techniques used to study surface reactions on high temperature materials. A brief description of HST2 shock tunnel is presented and this shock tunnel is capable of generating flow stagnation enthalpies ranging from 0.7 to 5 MJ/kg and has an effective test time of ~ 800 µs. High speed data acquisition system (National Instruments and Yokogawa) used to acquire data from shock tube experiments. The experimental methods like X-ray Photoelectron Spectroscopy (XPS), Scanning Electron Microscopy (SEM), X-ray diffraction (XRD), Raman and FTIR spectroscopy have been used to characterize the shock-exposed materials. Preliminary research work on surface nitridation of pure metals with shock heated nitrogen gas is discussed in Chapter 2. Surface nitridation of pure Al thin film with shock heated N2 is presented in Chapter 3. An XPS study shows that Al 2p peak at 74.2 eV is due to the formation AlN on the surface of Al thin film due to heterogeneous non-catalytic surface reaction. SEM results show changes in surface morphology of AlN film due to shock wave interaction. Thickness of AlN film on the surface increased with the increase in temperature of the shock heated nitrogen gas. However, HST2 did not produce sufficient temperature and pressure to carry out real conditions of re-entry. Therefore design and development of a new high enthalpy shock tunnel was taken up. In Chapter 4, we present the details of design and fabrication of free piston driven shock tunnel (FPST) to generate high enthalpy test gas along with the development of platinum (Pt) and thermocouple sensors for heat transfer measurement. A free piston driven shock tunnel consists of a high pressure gas reservoir, compression tube, shock tube, nozzle, test section and dump tank connected to a vacuum pumping system. Compression tube has a provision to fill helium gas and four ports, used to mount optical sensors to monitor the piston speed and pressure transducer to record pressure at the end of the compression tube when the piston is launched. Piston can attain a maximum speed of 150 m/s and compress the gas inside the compression tube. The compressed gas bursts the metal diaphragm and generates strong shock wave in the shock tube. This tunnel produces total pressure of about 300 bar and temperature of about 6000 K and is capable of producing a stagnation enthalpy up to 45 MJ/kg. The calibration of nozzle was carried out by measuring the pitot tube pressure in the dump tank. Experimentally recorded P5 pressure at end of the shock tube is compared with Numerical codes. Calibrated pressure P5 values are used to calculate the temperature T5 of the reflected shock waves. This high pressure and high temperature shock heated test gas interacts with the surface of the high temperature test materials. For the measurement of heat transfer rate, platinum thin film sensors are developed using DC magnetron sputtering unit. Hard protective layer of aluminum nitride (AlN) on Pt thin film was deposited by reactive DC magnetron sputtering to measure heat transfer rate in high enthalpy tunnel. After the calibration studies, FPST is used to study the heat transfer rate and to investigate catalytic/non-catalytic surface reaction on high temperature materials. In Chapter 5, an experimental investigation of non-catalytic surface reactions on pure carbon material is presented. The pure carbon C60 films and conducting carbon films are deposited on Macor substrate in the laboratory to perform shock tube experiments. These carbon films were exposed to strong shock heated N2 gas in the shock tube portion of the FPST tunnel. The typical shock Mach number obtained is about 7 with the corresponding pressure and temperature jumps of about 110 bar and 5400 K after reflection at end of the shock tube. Shock exposed carbon films were examined by different experimental techniques. XPS spectra of C(1s) peak at 285.8 eV is attributed to sp2 (C=N) and 287.3 eV peak is attributed to sp3 (C-N) bond in CNx due to carbon nitride. Similarly, N(1s) core level peak at 398.6 eV and 400.1 eV observed are attributed to sp3-C-N and sp2-C=N of carbon nitride, respectively. SEM study shows the formation of carbon nitride crystals. Carbon C60 had melted and undergone non-catalytic surface reaction with N2 while forming carbon nitride. Similar observations were made with conducting carbon films but the crystals were spherical in shape. Micro Raman and FTIR study gave further evidence on the formation of carbon nitride film. This experimental investigation confirms the formation of carbon nitride in presence of shock-heated nitrogen gas by non-catalytic surface reaction. In Chapters 6 and 7, we present a novel method to understand fully catalytic surface reactions after exposure to shock heated N2, O2 and Ar test gas with high temperature materials. We have employed nano ZrO2 and nano Ce0.5Zr0.5O2 ceramic high temperature materials to investigate surface catalytic reactions in presence of shock heated test gases. These nano crystalline oxides are synthesized by a single step solution combustion method. Catalytic reaction was confirmed for both powder and film samples of ZrO2. As per the theoretical model, it is known that the catalytic recombination reaction produces maximum heating on the surface of re-entry space vehicles. This was demonstrated in this experiment when a metastable cubic ZrO2 changed to stable monoclinic ZrO2 phase after exposure to shock waves. The change of crystal structure was seen using XRD studies and needle type monoclinic crystal growth with aspect ratio (L/D) more than 15 was confirmed by SEM studies. XPS of Zr(3d) core level spectra show no change in binding energy before and after exposure to shock waves, confirming that ZrO2 does not change its chemical nature, which is the signature of catalytic surface reaction. When a shock heated argon gas interacted with Ce0.5Zr0.5O2 compound, there was a change in colour from pale yellow to black due to reduction of the compound, which is the effect of heat transfer from the shock wave to the compound in presence of argon gas. The reduction reaction shows the release of oxygen from the compound due to high temperature interaction. The XPS of Ce(3d) and Zr(3d) spectra confirm the reduction of both Ce and Zr to lower valent states. The oxygen storage and release capacity of the Ce0.5Zr0.5O2 compound was confirmed by analyzing the reduction of Ce4+ and Zr4+ with high temperature gas interaction. When Ce0.5Zr0.5O2 (which is same as Ce2Zr2O8) in cubic fluorite structure was subjected to strong shock, it changed to pyrochlore (Ce2Zr2O7) structure by releasing oxygen and on further heating it changed to Ce2Zr2O6.3 which is also crystallized in pyrochlore structure by further releasing oxygen. If this heating is carried out in presence of argon test gas, fluorite structure can easily change to pyrochlore Ce2Zr2O6.3 structure, which is a good electrical conductor. Due to its oxygen storage capability (OSC) and redox (Ce4+/Ce3+) properties, Ce0.5Zr0.5O2 had been used as oxygen storage material in three-way-catalyst. Importance of these reactions is that the O2 gas released from the compound will react with gas released from the heat shield materials, like NOx, CO and hydrocarbon (HCs) species which results in reduction of temperature in the shock layer of the re-entry space vehicle. The compound Ce0.5Zr0.5O2 changes its crystal structure from fluorite to pyrochlore phase in presence of shock heated test gas. The results presented in these two Chapters are first of their kind, which demonstrates the surface catalytic reactions. In Chapter 8, we present preliminary results of the oxygen recombination on the surface of heat shield material procured from Indian Space Research Organization (ISRO) used as TPS in re-entry space capsule (Space capsule Recovery Experiment SRE-1) and on thin film SiO2 deposited on silicon substrate. The formation of SiO between the junctions of SiO2/Si was confirmed using XPS study when shock exposed oxygen reacted on these materials. The surface morphology of the ablated SiO2 film was studied using SEM. The damage induced due to impact of shock wave in presence of oxygen gas was analyzed using Focused Ion Beam (FIB) microscope. The results reveal the damage on the surface of SiO2 film and also in the cross-section of the film. We are further investigating use of FIB, particularly related to residual stress developed on thin films due to high pressure and high temperature shock wave interaction. In Chapter 9, conclusions on the performance of FPST, synthesis of high temperature materials, catalytic and non-catalytic surface reactions on the high temperature material due to shock-heated test gases are presented. Possible scope for future studies is also addressed in this Chapter.