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Zhu, Yumei, and August Österle. "China's policy experimentation on long-term care insurance: Implications for access." Wiley, 2019. http://dx.doi.org/10.1002/hpm.2879.
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China's population is aging rapidly, while the traditional long-term care (LTC) system that heavily relies on families is eroding. In response, China has embarked on a journey of policy experimentation for long-term care insurance (LTCI) since 2016, launching LTCI pilots in 15 pioneer cities. These pilots have a great diversity in participation, eligibility, and provision. This paper estimates the prevalence of LTC needs and analyzes the impact of the LTCI pilots on access. Although substantial progress has been achieved, the overall coverage of LTCI is still relatively small, and a large proportion of vulnerable people needing LTC seem to be left behind because of the strict eligibility criteria. This analysis suggests that future policy experimentation on LTCI reform in China needs to address the following pressing policy issues: expanding the coverage of LTCI; narrowing rural-urban disparities in access; improving access for vulnerable subpopulations; and reducing the heavy reliance on institutional care.
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Wu, Chao-Liang. "HPRT deficiency in cells and mice." Thesis, University of Edinburgh, 1993. http://hdl.handle.net/1842/11617.
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The hypoxanthine guanine phosphoribosyltransferase (HPRT) gene is a housekeeping gene, located on the X chromosome in both human and mouse. In humans, HPRT deficiency causes Lesch-Nyhan syndrome which is characterised by behavioural alterations, including self-injurious behaviour and mental retardation, while partial deficiency causes gouty arthritis. The use of homologous recombination to delete specific parts of the HPRT gene with the aim of studing the control of gene expression has been investigated. The size of the deletion that could be made using a simple procedure of homologous recombination was limited and there was a preference for an insertion mechanism if the targeting vectors were designed to delete more than 20 kb. However, combined with intrachromosomal recombination, the deletion size could be enlarged to at least 30 kb. Using this deletion targeting strategy, a mouse embryonic stem (ES) cell clone with a targeted deletion of the promoter and exons 1-2 in one allele of the adenine phosphoribosyltransferase (APRT) gene was also constructed. This deletion targeted ES clone provides the opportunity to generate APRT knock-out and HPRT/APRT double knock-out animal models for Lesch-Nyhan syndrome. Until recently no spontaneous behavioural abnormalities had been reported in HPRT-deficient mice generated using the embryonic stem cell system. To resolve the asymptomatic ambiguity of HPRT-deficient mice, a hypothesis that mice were more tolerant of HPRT deficiency because they were more reliant on APRT than HPRT for their purine salvage was proposed. The administration of an APRT inhibitor to HPRT-deficient mice induced persistent self-injurious behaviour. This combined genetic and biochemical model will facilitate the study of Lesch-Nyhan syndrome and the evaluation of novel therapies. A novel therapeutic strategy involving the intracerebral transplantation of ES cells was evaluated. HPRT activity was observed in the brain of HPRT-deficient mice which had received intracerebral ES cell transplantation. Some of the implanted ES cells were committed to differentiate down the neural pathway into either neurones or glial cells.
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Кисорець, А. В., та А. В. Вікул. "HPMC-капсули VcapsPlus – капсули нового покоління". Thesis, Київський національний університет технологій та дизайну, 2018. https://er.knutd.edu.ua/handle/123456789/11609.
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Mongkolpiyawat, Jiraporn. "The effect of organic salts on HPMC." Thesis, University of Nottingham, 2012. http://eprints.nottingham.ac.uk/28993/.
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The presence of organic salts as drug counter-ions and buffers in hydroxypropylmethylcellulose (HPMC) matrices is often overlooked. This study investigates their potential to influence polymer solution properties and matrix drug release kinetics. A homologous series of aliphatic organic salts influenced solution and matrix properties in rank order of hydrocarbon chain length. Monovalent salts containing 1to4 C-atoms had little effect on polymer surface activity, but lowered sol:gel transition temperatures (SGTT), and accelerated matrix drug release in comparison with a dextrose control. Divalent salts were more potent. These observations are consistent with Hofmeister effects in which anions restructure water in the polymer hydration sheath, induce 'salting-out' and suppressing particle swelling and matrix gel layer formation. Organic salts with StoB C-atoms increasingly influenced polymer surface activity, elevated SGTT, and retarded matrix drug release. This suggests these salts enhance HPMC hydration, possibly through interaction with hydrophobic regions. The effects of these salts on matrix drug release show that these ions impact on water:polymer interactions important to gel layer formation and diffusion barrier properties. HPMC matrices containing SOS and its homologues were also investigated. Turbidimetric, tensiometric and rheological studies supported a mechanism in which these surfactants solubilise HPMC at post-micellar concentrations. Incorporating 10% SOS into HPMC matrices was shown to increase the resistance of HPMC matrices to sucrose medium up to 2.0M, suggesting a role for surfactants in avoiding food solute effects. This study shows that organic salts incorporated in HPMC matrices have the potential to influence drug release in a rank order that reflects their modulation of the HPMC polymer hydration sheath in solution. SOS and its homologous series could retard drug release from HPMC matrices only when their critical aggregation concentration (CAC) was reached. However, it suggests this excipient may have uses as an excipient for improving HPMC matrix release performance.
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Keane, Richard. "HPMA copolymer-aminoellipticine conjugates : mechanism of action." Thesis, University College London (University of London), 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.269617.
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Shahri, Mehdi Abbaszadeh. "Detecting and modeling cement failure in high pressure/ high temperature wells using finite-element method." Thesis, Texas A&M University, 2005. http://hdl.handle.net/1969.1/3241.
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A successful cement job results in complete zonal isolation while saving time and money. To achieve these goals, various factors such as well security, casing centralization, effective mud removal, and gas migration must be considered in the design. In the event that high-pressure and high-temperature (HPHT) conditions are encountered, we must attempt to achieve permeability in the set cement to prevent gas migration and to prevent any other fluid passing through to collapse the entire structure. Therefore, the design of the cement must be such that it prevents: Micro-annuli formation Stress cracking Corrosive fluid invasion Fluid migration Annular gas pressure In HPHT cases, we need more flexible cement than in conventional wells. This cement expands more at least 2 to 3 times more in some special cases. The stress in the cement is strongly connected with temperature and pressure, as well as lithology and in-situ stress. If we can define a method which connects the higher temperature to the lower stress field, we would have the solution for one side of the equation, and then we could model the pressure (stress principles) at the designated depth and lithology. Since the stress is so dependent on temperature, the temperature variation must be accurately predicted to properly design the fluid and eliminate excessive time spent waiting on cement. In addition, a post-job analysis is necessary to ascertain zonal isolation and avoid unnecessary remedial work. By increasing the flexibility of the set cement (lowering the Young's modulus), we can reduce the tensile stress in the cement sheath during thermal expansion. This could be a solution to the problem of cement stability in high temperature cases. Here we report the use of the finite-element method (FEM) to investigate the stress fields around and inside the cement, and to forecast the time of failure and its affect on cement integrity. This method is more powerful than conventional stability methods since complex boundary conditions are involved as initial conditions and are investigated simultaneously to more accurately predict cement failure. The results of this study show the relevant dependency of stress principles with temperature and pressure. These results clarify the deformation caused by any disturbance in the system and the behavior of under-stress locations based on their relative solid properties.
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Themis, Michael. "Retrovirus insertional mutagenesis : experiences at the hprt locus." Thesis, Brunel University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307483.
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Hu, Anran. "Mixed polymer hydrophilic matrices containing HPMC and PEO." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/31558/.
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The research in this thesis describes investigations of (i) mixed polymer HPMC and PEO hydrophilic matrices and their performance in low and high ionic environments and (ii) understanding the internal behaviour of HPMC and PEO mixed systems. It was postulated that using a blend of these polymers might provide advantages over the use of single polymers. A series of ‘realistic’ 30% w/w polymer matrix formulations, containing different weight ratios of HPMC and PEO and a soluble model drug (caffeine), were tested in ionically challenging media, up to 1M sodium chloride (NaCl). Dissolution testing showed how HPMC dominated formulations exhibited accelerated release in high ionic strength media (0.8M NaCl or higher), whereas PEO dominated formulations did not. Power law analyses suggested the release mechanism of matrices in 0.6M NaCl and below were anomalous non-Fickian transport, but case II transport was observed in HPMC dominated matrices at 0.8M NaCl and above. A polymer ratio of 4:6 HPMC:PEO allowed an extended release tablet to be formulated that was resistant to 1M NaCl. In 0.6M NaCl or below, increasing the proportion of HPMC in a mixed HPMC:PEO tablets, increased the duration of extended release. Confocal laser scanning microscopy was used to investigate the structure of the HPMC:PEO matrix hydrated gel layer. The results provided evidence that HPMC and PEO particles swell independently in the gel layer. They remained substantially unmixed during gel layer formation, and each appeared to contribute independently to gel layer structure. Magnetic resonance imaging showed how PEO matrices hydrated more rapidly than HPMC matrices, but PEO matrices completely dissolved after 9 hours. In the case of 4:6 HPMC:PEO and HPMC matrices, a hydrated gel remained. This reflected the behaviour of these matrices in the dissolution tests. Unfortunately, MRI could only be applied in zero salt media, as the dielectric properties of NaCl interfered with the results, and other techniques were required to examine matrix behaviour in high salt media. Texture analysis showed that at low NaCl concentrations, the HPMC gel layer exhibited higher gel strength than PEO, and that by substituting HPMC for PEO increased gel layer strength was obtained. The later stages of gel layer morphology were also investigated by digital optical macroscopy. Images showed greater gel longevity of HPMC and mixed matrices, with evidence for a higher gel strength and less erosion than PEO matrices. Swelling of single polymer particles showed how increasing NaCl concentration significantly inhibited HPMC particle swelling but only had a limited effect on PEO particle swelling. The ability of PEO particles to swell in high salt media may explain the resistance of PEO matrices to high NaCl dissolution media. The miscibility of HPMC and PEO in dilute solution was studied by rheology and phase contrast microscopy. Measurements of storage modulus (G’) at 1% w/v showed how most polymer mixtures showed negative deviations from ideal mixing at all oscillatory frequencies studied (0.1Hz, 1Hz, and 10Hz). This is evidence that these polymers are immiscible in solution. Phase contrast microscopy provided direct optical evidence of phase separation in blended HPMC:PEO solutions (4% w/v). The tendency of these polymers to be immiscible, suggests that they may also be phase separated in the more concentrated environment of the gel layer. Gel layer morphology in binary polymer tablets was investigated directly by confocal microscopy (up to 15 min) and by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) up to 3 hours. The confocal microscopy images showed that HPMC and PEO appeared to swell independently during early gel layer. Each polymer appeared to contribute independently to gel layer structure. ATR-FTIR imaging allowed chemical mapping of the three components (water, PEO and HPMC) in the gel layer, providing evidence that each polymer formed individual domains. PEO appears to be more extensively swollen than HPMC and may form the outer part of the gel layer, protecting HPMC from the effect of high ionic media. The work in this thesis suggests that mixed polymer HPMC:PEO matrices may have certain advantages over the use of matrices containing only single polymer. PEO confers resistance to highly ionic media, while HPMC provides a longer drug release than PEO alone. Each polymer appears to contribute separately to the gel layer, but the ability of PEO to swell in highly ionic environments, may allow formation of a diffusion barrier that protects the incorporated HPMC from ionic media, and allows it to contribute to gel layer structure.
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Galloon, Terry. "Biochemical and genetic properties of HPRT Cape Town." Master's thesis, University of Cape Town, 1987. http://hdl.handle.net/11427/26591.
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An unusual partial HPRT deficient mutant, HPRT Cape Town was observed to have a low activity in erythrocyte lysates at high concentrations of the purine substrates, hypoxanthine and guanine. This substrate inhibition was not observed with the substrate PPRP. The low activity was not associated with changes in the Km or Vmax for any of the substrates (Steyn and Harley, 1984). The kinetics of the proband's enzyme was studied in lymphoblast extracts. The characteristic substrate inhibition was observed which showed that this phenomenon was not confined to erythrocytes but was a more generalized phenomenon. This result implies that the decreased HPRT activity observed in the proband is due to substrate inhibition by the purine bases. The HPRT enzyme is coded for by a gene which is located on the X chromosome (Pai et al., 1980). The proband's daughter was therefore studied in order to determine the cause of the mutation. It was not known whether the substrate inhibition was the result of a mutation in the gene coding for the enzyme, a mutation which results in altered post-translational modification or the absence or alteration of factors influencing normal HPRT kinetics. The daughter's transformed lymphoblasts exhibited growth patterns in selective media that resembled those of her father. The daughter's enzyme prepared from lymphoblast extracts exhibited the characteristic substrate inhibition. These results suggest that this cell line results from the selection of a clone or clones which have suppressed the function of the X chromosome carrying the maternal and presumably normal HPRT allele. The daughter's enzyme prepared from erythrocyte lysates exhibited intermediate enzyme activity between that of the proband and a normal control. This result suggests that the daughter is an obligate heterozygote and that the defect is due to a mutation in the HPRT gene itself. The defect was studied at the gene level. No difference was observed in the banding patterns of the proband's DNA and control DNA which were digested with various restriction enzymes and hybridized to ³²p-labelled HPRT cDNA. The size of the HPRT mRNA of the proband was the same as the control. These results imply that there is no major gene alteration; this is expected since the proband only has a partial deficiency of the enzyme. The HPRT cDNA was subcloned into a riboprobe vector, pGEM-3. The T7 promoter was used to transcribe antisense RNA strands which were then hybridized to the proband's RNA and control RNA. No difference was observed in the size of the protected fragment. This result does not exclude the possibility of a point mutation as the cause of the defect in HPRT Cape Town.
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Lara, Cruz José Luiz. "Caractérisation thermodynamique des ELV HPHT dans les saumures." Thesis, Pau, 2019. http://www.theses.fr/2019PAUU3016/document.
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Cette thèse s’est déroulée dans le cadre du projet FONGEOSEC, qui vise à développer la filière de la géothermie profonde en France avec la conception d’un démonstrateur d’une centrale de production d’énergie géothermique dans le bassin Rhénan. Ce projet est piloté par Fonroche Géothermie, qui gère un consortium de plus de dix acteurs du milieu académique et industriel. Le financement du projet est réalisé avec participation de l’Agence de l’Environnement et de la Maîtrise de l’Énergie (ADEME). Ainsi, les travaux exposés dans ce document se sont intéressés à la caractérisation thermodynamique des fluides géothermaux (saumures chaudes contenant des gaz dissous) de la région ciblée par le projet. Il est nécessaire de déterminer la solubilité de chacun des gaz dissous dans ces saumures aux conditions de pression, température et salinité de l’exploitation géothermique. Des modèles thermodynamiques de prévision des équilibres entre phases liquide et vapeur peuvent être utilisés pour estimer ces solubilités. Néanmoins, en absence des mesures expérimentales dans les conditions de pression, température et salinité d’intérêt, pour effectuer la régression de paramètres de ces modèles, il sera difficile d’obtenir avec précision ces solubilités à partir de simulations. Ainsi, cette thèse est centrée sur l’étude expérimentale des solubilités des gaz dans des saumures représentatives des fluides du bassin Rhénan. La gamme de pression de FONGEOSEC va de 6.0 MPa à 40.0 MPa pour des températures de 333.15 K et 453.15 K. Le dispositif expérimental utilisé dans cette thèse fonctionne dans ces conditions. Les gaz dissous dans les saumures visées par le projet sont constitués essentiellement de dioxyde de carbone (CO2), puis d’azote (N2) et enfin de méthane (CH4) en plus faibles quantités. Les sels dissous dans ces fluides sont surtout du chlorure de sodium et du chlorure de calcium, à molalité de 1.2 mol NaCl-0.2 mol CaCl2.Kg H2O-1. Dans cette thèse, nous avons effectué la détermination expérimentale de la solubilité du dioxyde de carbone dans des saumures typiques du bassin Rhénan aux conditions de pression et de température du projet FONGEOSEC. Des réflexions sont proposées quant à une méthodologie d’analyse de solubilité du méthane et de l’azote dans des phases aqueuses. Nous observons aussi que dans les conditions de pression et température de fond du puits, la solubilité du dioxyde de carbone dans les saumures typiques du bassin Rhénan est la plus élevée parmi toutes les conditions caractérisées. Une étude du sating-out effect dans ces saumures est également proposée dans cette thèse. Enfin, il est remarqué que le modèle de Pitzer (Pitzer.dat sur PhreeqC) semble prédire de façon correcte nos mesures expérimentales à 333.15 K, mais il perd son efficacité à 453.15 K. Dans cette condition, le modèle E-NRTL (Simulis®) semblerait être plus approprié<br>This thesis was part of the FONGEOSEC project, which aims to develop the deep geothermal energy sector in France through the the design of a geothermal power pilot plant on the Upper Rhine Graben. This project is controled by Fonroche Géothermie, which manages a consortitium of more than ten academic and industrial partners. The French Environment & Energy Management Agency (ADEME) participates at the fundings of the project.Therefore, the work exposed in this document concerns the thermodynamic characterisation of geothermal fluids (hot brines containing dissolved gases) from the target region of this project. It is thus necessary to determine the solubility of each gas dissolved in these brines at the pressure, temperature and salinity conditions of geothermal energy exploitation.Thermodynamic models that predict liquid-vapour phase equilibrium can be used to estimate these solubilities. However, if there is a lack of experimental measures on the pressure, temperature and salinity conditions of interest, it will not be possible to regress these models interaction parameters and, therefore, it will be difficult to have precise solubility results from these thermodynamic simulations. Thus, this thesis has focused on the experimental study of gas solubilities in brines representing the Upper Rhine Graben fluids. The pressure range of the FONGEOSEC project goes from 6.0 MPa to 40.0 MPa for temperatures of 333.15 K and 453.15 K. The experimental setup used on this thesis can operate at these conditions. Dissolved gases in the brines concerned by this project are mainly composed by carbon dioxyde (CO2), and then by nitrgen (N2) and methane (CH4) at lower quantitites. Dissolved salts in these fluids are basically chloride sodium and chloride calcium, at molalities of 1.2 mol NaCl-0.2 mol CaCl2.Kg H2O-1.On the scope of this thesis, we have performed the experimental determination of carbon dioxyde solubility in Upper Rhine Graben-type brines at the pressure and temperature conditions of the FONGEOSEC project. We propose a discussion about an analysis methodology for measuring nitrogen and methane solubility in aqueous phases. We also observed that at the pressure and temperature conditions found at the bottom of the production well, carbon dioxyde solubility in the Upper Rhine Graben-type brines reaches its highest value among all the conditions studied in this thesis. A salting-out effect study in these brines is also proposed in this document. Finally, it is noticed that the Pitzer model (Pitzer.dat at PhreeqC) seems to predict properly our experimental data at 333.15 K, but it is less efficient at 453.15 K. In this condition, the E-NRTL model (Simulis®) seems to be more appropriate
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Eriksson, Kjell. "HPM-vapen vs. kommersiell UAV." Thesis, Försvarshögskolan, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:fhs:diva-6273.
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Detta arbete i militärteknik studerar om högeffektpulsad mikrovågsstrålning kan uppnå verkan mot kommersiella UAV. Analysen genomförs på två olika icke-dödliga HPM-vapen. Data hämtas från ett scenario där vapenverkan innebär hög risk för skada på tredje man. En Försvarsmaktsstudie har konstaterat att Luftvärnsbataljon saknar förmåga att verka mot små UAV.Dagsaktuell kunskap har inhämtats om scenariots miljö samt från forskning och industri genom studiebesök. Inhämtad kunskap har möjliggjort en logisk-matematisk parameterstudie på ett scenario med militärtekniskt perspektiv. Analysens slutsatser är att kommersiella UAV innehar låg skyddsnivå, att beslut om insats underlättas i alla miljöer och att en elektronisk sköld i form av HPM-vapen skyddar en stor volym samtidigt. HPM-vapen kan inte som ensamt vapensystem stå för skydd och uppnå säkerställd verkan mot kommersiell UAV. HPM-vapen kan däremot komplettera övriga verkanssystem och göra luftförsvaret starkare genom system av system. HPM-vapen kan bidra till att minska ett befintligt förmågeglapp mot kommersiella UAV.<br>This paper in military technology discusses whether high power microwaves can affect commercial UAVs. Two non-lethal HPM-weapons are analyzed. The data is collected from a scenario where there is a high risk for collateral damage. A Swedish Armed Forces study stated that the Air Defence Battalion lacks ability to affect small UAVs. The latest knowledge is obtained from the environment in the scenario, from research and from the industry. This knowledge has enabled a logical-mathematical parametric study on the scenario within a military perspective. The result of the study is the assessment that commercial UAVs are assessed to have low protection factor, facilitates decision to act in all environments and provides an electronic shield protection of a large surface at the same time. HPM-weapons can´t stand as a single system for protection against commercial UAVs and achieve guaranteed effect. However, HPM-weapons can complement other weapon systems and thus make the air defense stronger through systems of systems. HPM-weapons can reduce the capability deficiency against commercial UAVs.
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El-Gouhary, Inas. "Targeted transgenesis : the hypoxanthine phosphoribosyl transferase (HPRT) gene locus." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80256.
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To overcome the limitations that accompanied traditional transgenesis using pronuclear injections, multiple methods have been employed to target a single copy of a transgenic sequence to a chosen location in the genome. One of which is the introduction of a construct as a single copy, in a known orientation, upstream of the hprt (hypoxanthine phosphoribosyl transferase) gene. The present study is designed to characterize the influence this locus could impose on the expression capability of the docked sequence.<br>Consistent ectopic expression of reporter constructs bearing different Myelin Basic Protein (mbp) regulatory elements and docked at the hprt locus was noted in cardiomyocytes and major CNS blood vessels; two sites in which mbp is not thought to be expressed. This ectopic expression originated from endogenous hprt enhancer activity as similar mbp reporter constructs, randomly inserted, did not reproduce the same expression phenotypes.<br>In addition, this work also unraveled aspects of the complex nature of mbp gene regulation. The results obtained from this study reveal that reporter constructs containing mbp enhancer elements docked in hprt locus expressed ectopically in the cartilagenous cells of the vertebral bodies during the mouse mid-fetal development period.<br>Finally, analysis of the "enhancer trap" construct exposed additional ectopic expression in the muscles of the back and tongue uncovering further hprt enhancer activity. Surprisingly, when mbp enhancer sequences were added to the "enhancer trap" construct, marked reduction in muscle expression was noted.
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Rossiter, B. J. F. "Structure and mutation of the Chinese hamster HPRT gene." Thesis, University of Manchester, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378035.
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Mashhadikarimi, Meysam. "Obtaining triple layer polycrystalline diamond compact by HPHT method." PROGRAMA DE P?S-GRADUA??O EM CI?NCIA E ENGENHARIA DE MATERIAIS, 2017. https://repositorio.ufrn.br/jspui/handle/123456789/23749.
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Previous issue date: 2017-07-10<br>Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)<br>Neste trabalho de pesquisa, foi obtido um compacto de diamante policristalino (PDC), constitu?do de uma camada superior de diamante policristalino sob um substrato de WC-10% em peso de Co e uma interface de WC-20% em peso de Nb/Ni entre as camadas, atrav?s de m?todo de sinteriza??o de alta press?o e alta temperatura (HPHT). Para alcan?ar esse objetivo, foram realizadas tr?s etapas distintas. Na primeira etapa, foi sinterizado o corpo de diamante com um ligante adequado, e foram obtidos os melhores par?metros de sinteriza??o. Na segunda etapa, foi realizado o estudo de diferentes condi??es de sinteriza??o para o substrato de metal duro WC-10% p.Co. E, na terceira e ?ltima etapa, foi produzido, de acordo com os resultados alcan?ados nas etapas anteriores, o compacto de diamante policristalino de camada tripla (PDC). Na primeira etapa, quatro ligantes diferentes foram usados para sinterizar o diamante atrav?s do m?todo HPHT. Os ligantes utilizados foram o Nb/Fe, Nb/Co, Nb/Ni e Nb puro, sendo 10% em peso de ligante utilizado para cada composi??o. A sinteriza??o foi realizada a diferentes temperaturas e sob diferentes press?es e tempos. As amostras obtidas foram analisadas atrav?s das medidas de densidade relativa e dureza, al?m das imagens eletr?nicas de varredura, para encontrar os melhores par?metros de sinteriza??o e ligante. Os estudos mostraram que o Nb apresentou o melhor comportamento, e que os melhores par?metros de sinteriza??o foram: T = 1750 ?C, P = 7,7 GPa, t = 6 minutos. Na segunda etapa, uma mistura em p? de WC-10% em peso de Co foi sinterizado atrav?s de HPHT sob press?o de 7,7 GPa, variando temperatura (1500 ?C, 1600 ?C, 1700 ?C, 1800 ?C, 1900 ?C) e tempo (2 e 3 minutos). As an?lises microestruturais e estruturais foram realizadas atrav?s de MEV/EDS e DRX. Ensaios de dureza, tenacidade (ITF) e de resist?ncia ? compress?o, tamb?m, foram realizados para entender os efeitos de diferentes par?metros de sinteriza??o nas propriedades dos sinterizados, verificando-se densifica??o total das amostras sinterizadas a altas temperaturas. Entretanto, foi observado um crescimento anormal de gr?os para estas mesmas temperaturas. Altos valores de dureza foram observados, aproximadamente, entre 1250 a 1650 HV para todas as amostras sinterizadas. Na terceira etapa, para a obten??o do PDC, uma camada fina de WC-20% em peso de Nb/Ni foi utilizada para a forma??o da interface entre a camada superior de diamante com ligante de Nb pura e o substrato de WC 10% em peso de Co. A sinteriza??o foi feita atrav?s do m?todo HPHT ? temperatura de 1750 ?C sob 7,7 GPa de press?o. Foram utilizados dois tempos diferentes, de 6 min. (tr?s sucessivos 2 minutos) e 9 min. (tr?s sucessivos 3 minutos). A dureza foi medida e os estudos estruturais/microestruturais foram realizados atrav?s de an?lises de MEV/EDS. Em suma, os resultados mostraram que este novo tipo de PDC pode ser produzido com sucesso, usando um novo ligante, o niobio puro, para o diamante, sem qualquer presen?a de grafitiza??o. Verificou-se tamb?m que o uso de uma interface com os mesmos elementos constituintes do substrato e do corpo de diamante sinterizado resultou numa boa ades?o entre as camadas, o que pode resultar em melhor desempenho e melhorar a durabilidade do PDC.<br>The primary objective of this thesis was to obtain a triple layer polycrystalline diamond compact (PDC) containing a polycrystalline diamond as top layer, a WC 10 wt% Co substrate, and a WC 20 wt% Nb/Ni interface to bond these two layers via high pressure high temperature (HPHT) sintering. To achieve this objective, the project has been done in three different stages. The first stage was producing diamond sintered body with a suitable binder, and finding the best sintering parameters. The second stage of project was done to study the WC 10 wt% Co hardmetal substrate at different sintering conditions, and the third and last stage was done according to the results achieved from previous stages to obtain a triple layer PDC. At the first stage, four different binders were used to sinter diamond under HPHT condition. Binders were Nb/Fe, Nb/Co, Nb/Ni and pure Nb and 10 wt% binder was used. Sintering was carried out at different temperature and under different pressure and holding time. Obtained samples were studies according to relative density, microstructure, and hardness to find the optimum binder and sintering parameters. Studies at this stage showed that Nb is the best binder and T=1750 ?C, 7.7 GPa with holding time more than 6 minutes are the best sintering parameters. At the second stage a powder mixture of WC 10 wt% Co was sintered via HPHT at 1500, 1600, 1700, 1800, and 1900?C under 7.7 GPa pressure for 2 and 3 minutes. Microstructural/structural analyses were performed by SEM/EDS and XRD and hardness, Indentation Fracture Toughness (ITF) and compression tests were also carried out to understand effects of different sintering parameters. At this stage, it was found that full density can achieved for high sintering temperature along with abnormal grain growth. High hardness was observed in range starting from 1250 up to 1650 HV. At the third stage, to obtain PDC, a thin layer of WC 20 wt% Nb/Ni was used as an interface between top layer of diamond with pure Nb binder and WC 10 wt% Co substrate. Sintering was done via HPHT method at 1750?C under 7.7 GPa of pressure. Two different holding time of 6 (three successive 2 minutes) and 9 (three successive 3 minutes) were used. Hardness was measured and microstructural/structural studies were done via SEM/EDS. The overall results showed that this new kind of PDC can successfully produce using a new pure Niobium binder for diamond without any graphitization. It was also found that using an interface having the resemblance to both substrate and sintered diamond body caused good adhesion between layers that can results in enhanced performance and improving durability of PDC.
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Rajabi-Siahboomi, Ali Reza. "Hydroxypropylmethylcellulose in hydrophilic matrix dosage forms." Thesis, University of Nottingham, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385287.
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Pygall, Samuel R. "Critical processes in drug release from HPMC controlled release matrices." Thesis, University of Nottingham, 2009. http://eprints.nottingham.ac.uk/14128/.
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This study has investigated the drug release mechanisms from hydroxypropyl methylcellulose (HPMC) hydrophilic matrices. A hypothesis was developed from interpretation of a previous study that drug surface activity has an influence on drug liberation. The validity of the hypothesis was tested by studying the interactions between HPMC and the two non-steroidal anti-inflammatory drugs diclofenac Na and meclofenamate Na, using tensiometry, rheology, NMR, neutron scattering and turbimetry. Meclofenamate Na was found to interact with HPMC, resulting in detectable changes in drug diffusion coefficients and polymer structure in solution. There were increases in HPMC solution solubility and changes in viscoelasticity, which suggested drug solubilisation of the methoxyl-rich regions of the polymer chains. Diclofenac Na did not show evidence of an interaction and exhibited changes consistent with a 'salting out' of the polymer. A confocal microscopy technique was used to image the drug effects on early gel layer development. The presence of drugs affected gel layer development, depending on the level of drug in the matrix and the concentration of sodium chloride in the hydration medium. Diclofenac Na matrices became increasingly susceptible to disintegration, while meclofenamate Na matrices exhibited resistance to the effects of sodium chloride. The influence of incorporated diluents on the gel layer was also investigated and it was found that lactose had a disruptive effect, whereas microcrystalline cellulose was relatively benign. When co-formulating drugs and diluents in the matrix, lactose acted to antagonise the effect of meclofenamate, but acted synergistically with diclofenac to reduce gel layer integrity and accelerate matrix disintegration. In contrast, MCC was found to have a relatively neutral effect on drug-mediated effects. HPMC particle swelling and coalescence are critical processes in gel layer formation extending drug release. Drug surface activity and capability of interacting with HPMC appears to influence particle swelling processes, affecting gel layer formation and provides a mechanistic explanation for the differing release profiles of diclofenac and meclofenamate Na.
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Williams, Hywel David. "Exploring the mechanisms of direct food-effects on HPMC behaviour." Thesis, University of Nottingham, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.546254.
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Narahara, Sheryl K. "Occupational narratives of human performance technology (HPT)." [Bloomington, Ind.] : Indiana University, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3329712.
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Thesis (Ph.D.)--Indiana University, Dept. of Instructional Technology, 2008.<br>Title from PDF t.p. (viewed on Jul 19, 2010). Source: Dissertation Abstracts International, Volume: 69-10, Section: A, page: 3919. Adviser: Thomas Schwen. Includes supplementary digital materials.
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Wessman, Thomas. "HPM som luftvärnsvapen mot kryssningsmissiler, en möjlighet?" Thesis, Försvarshögskolan, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:fhs:diva-1640.
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I denna uppsats undersöks huruvida HPM (High Power Microwaves) kan användas som enverkansform i framtida luftvärnssystem för att bekämpa kryssningsmissiler. Studien undersökervilket hot kryssningsmissiler kan utgöra, hur de är konstruerade och hur HPM kan påverka dem.Uppsatsen redogör för hur det nya luftvärnskonceptet är uppbyggt och vilka krav på förmågor somställs på framtida luftvärnssystem. Den undersöker även hur ett HPM-system är uppbyggt ochvilken verkan det kan ha på elektriska system i en kryssningsmissil. Vidare diskuteras vilkeneffekt tre olika HPM-system kan ha mot kryssningsmissiler kopplat till de krav som ställs iluftvärnskonceptet.Huvudslutsatsen indikerar att HPM-system kan ha verkan mot kryssningsmissiler. HPM-systemkan nyttjas främst i scenarier där det ställs höga krav på eldhastigheten mot kryssningsmissiler påkorta avstånd. Ett problem är att det är svårt att utvärdera och konstatera skadeeffekten ikryssningsmissilen.<br>Avdelning: ALB - Slutet Mag 3 C-uppsHylla: Upps. ChP T 03-05
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Borge, Lucas Ferreira. "Análise comparativa de perfis de dissolução in vitro e in silico de comprimidos de liberação modificada contendo metformina." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/9/9139/tde-04122018-120622/.
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A dissolução de um fármaco a partir de uma forma farmacêutica (FF) sólida oral é um pré-requisito para que o mesmo seja absorvido pelo organismo e cumpra seus efeitos terapêuticos. O ensaio de dissolução de medicamentos permite avaliar a quantidade de princípio ativo que é liberado a partir de sua FF, mimetizando in vitro o processo que ocorre no trato gastrointestinal (TGI). O DDDPlus® é o único programa de computador dedicado exclusivamente a simular ensaios de dissolução. O objetivo deste trabalho foi avaliar a capacidade do programa de computador DDDPlus® em fornecer perfis de dissolução in silico de comprimidos matriciais contendo metformina semelhantes aos perfis de dissolução in vitro e avaliar a possibilidade de substituir a comparação de perfis de dissolução in vitro de diferentes formulações de comprimidos matriciais contendo metformina pela comparação de perfis de dissolução in silico fornecidos pelo DDDPlus®.Para tanto, um planejamento estatístico foi realizado para obtenção de perfis de dissolução, variando a velocidade das pás e o uso do sinker. Os perfis de dissolução de 3 formulações teste (T1, T2 e T3) de comprimidos de liberação modificada por matriz polimérica contendo metformina foram comparadas pelos métodos de eficiência de dissolução (ED), tempo médio de dissolução (TMD), fator de diferença (f2) e fator de semelhança (f1). Os resultados indicaram o uso do sinker como fator determinante para a ED e TMD. Assim, o método que utilizava o sinker e a velocidade das pás de 50RPM foi utilizado para avaliar 4 produtos comercializados no Brasil. No DDDPlus® os ensaios de dissolução in vitro das formulações T1, T2 e T3 foram otimizadas para a obtenção das constantes de calibração (CC), as CC foram utilizadas para simular os ensaios de dissolução de T1, T2 e T3 em velocidades de 25 e 50RPM. Os perfis de dissolução simulados foram comparados aos perfis observados, resultando em valores de R2. Valores de R2 acima de 0,90 foram obtidos para todas as simulações realizadas utilizando CC de ensaios in vitro que utilizaram sinker, indicando o potencial do programa em auxiliar o desenvolvimento de novas formulações. Valores de R2 abaixo de 0,70 foram obtidos após a simulação de ensaios utilizando CC de ensaios in vitro que não utilizavam o sinker, indicando que o programa de computador não previu a adesão do comprimido ao fundo da cuba de dissolução durante o ensaio. Os perfis de dissolução simulados das formulações T1, T2 e T3 foram comparadas por f1 e f2 com os perfis de dissolução dos produtos do mercado. Tais comparações concluíram que o software não é indicado como substituto dos ensaios in vitro quando se almeja comparar perfis de dissolução.<br>Dissolution of a drug from an oral solid pharmaceutical form (FF) is a prerequisite for it to be absorbed by the body and to fulfill its therapeutic effects. in vitroDrug dissolution assay allows the amount of active principle released from a FF and mimics the in vivo the process that occurs in the gastrointestinal tract (TGI). DDDPlus® is the only computer program dedicated exclusively to simulating dissolution testing. The objective of this work was to evaluate the ability of DDDPlus® software to provide in silico dissolution profiles of matrix tablets containing metformin similar to in vitro dissolution profiles and to evaluate the possibility of replacing in vitro dissolution profiles comparison of different formulations of matrix tablets containing metformin for a comparison of in silico dissolution profiles provided by DDDPlus®. For this purpose, a statistical design was used, varying agitation speed and the use of sinker to obtain dissolution profiles for 3 test formulations (T1, T2 and T3) of polymer matrix-modified release tablets containing metformin. Dissolution profiles were compared by means of dissolution efficiency (ED), mean dissolution time (TMD), difference factor (f2) and similarity factor (f1). The results indicated the use of sinker as a determinant factor for ED and TMD. Thus, the method that used sinker and agitation speed of 50RPM was used to evaluate 4 products commercialized in Brazil. in vitro dissolution tests of the T1, T2 and T3 formulations were optimized using In DDDPlus® to obtain the calibration constants (CC), which were used to simulate dissolution profiles of T1, T2 and T3 at speeds of 25 and 50RPM. in silico dissolution profiles were compared to in vitro dissolution profiles, resulting in R2 values. R2 values above 0.90 were obtained for all simulations performed using CC from in vitro assays using sinker, indicating the potential of the program to assist the development of new formulations. R2 values below 0.70 were obtained after the simulation of assays using CC from in vitro assays that did not use the sinker, indicating that the computer program did not predict adhesion of the tablet to the bottom of the dissolution cell during the assay. The simulated dissolution profiles of the T1, T2 and T3 formulations were compared by f1 and f2 with the dissolution profiles of the market products. Such comparisons concluded that the software is not indicated as a substitute for in vitro assays when comparing dissolution profiles is desired.
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Banks, Simon. "Incompatibilities between HPMC and model drugs : consequences for extended drug release." Thesis, University of Nottingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.421473.
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Jayan, Arvind. "Investigating the drug release mechanisms of mixed HPMC/PEO hydrophilic matrices." Thesis, University of Nottingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.444075.
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Viswanathan, Anup. "Viscosities of natural gases at high pressures and high temperatures." Texas A&M University, 2003. http://hdl.handle.net/1969.1/5823.
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Estimation of viscosities of naturally occurring petroleum gases provides the information
needed to accurately work out reservoir-engineering problems. Existing models for
viscosity prediction are limited by data, especially at high pressures and high
temperatures. Studies show that the predicted viscosities of natural gases using the
current correlation equations are about 15 % higher than the corresponding measured
viscosities at high pressures and high temperatures.
This project proposes to develop a viscosity prediction model for natural gases at high
pressures and high temperatures.
The project shows that commercial gas viscosity measurement devices currently
available suffer from a variety of problems and do not give reliable or repeatable results.
However, at the extremely high pressures encountered in high pressure and high
temperature reservoirs, the natural gases consist mainly of methane as the hydrocarbon
constituent and some non-hydrocarbon impurities. Available viscosity values of methane were used in the development of a correlation for predicting the viscosities of naturally
occurring petroleum gases at high pressures and high temperatures. In the absence of
measurements, this correlation can be used with some confidence.
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Arzaghi, Mandana. "Nouveau procédé d'hyperdéformation pour les tubes." Thesis, Metz, 2010. http://www.theses.fr/2010METZ031S.
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La nouvelle technique d'hyperdéformation nommée High Pressure Tube Twisting (HPTT), est un procédé continu d'affinement du grain pour les matériaux métalliques avec la géométrie tubulaire. Il consiste à placer un mandrin dans le tube avant d'appliquer une compression axiale directement sur le tube confiné des deux côtés pour produire une pression hydrostatique importante. Le tube est ensuite cisaillé par un couple externe à l'aide de la force de frottement généré par la pression hydrostatique. Les structures ultrafines produit avec HPTT ont été confirmés par MET et leur propriétés mécaniques ont été évaluées. La limite d'élasticité est augmentée de façon monotone avec la déformation imposée par HPTT. L'évolution de la microstructure est étudiée par la technique EBSD et les mesures de texture ont été réalisées avec des rayons X. Les échantillons déformés ont la texture de cisaillement simple, avec des intensités relativement faibles et l'effet de la texture initiale sur la texture finale persiste jusqu'à un cisaillement de 6. La distribution des désorientations entre les grains est bimodale et le second pic augmente avec la déformation. Application industrielle de cette nouvelle technique SPD exige la modélisation avancée en termes d'évolution de texture et le processus de fragmentation des grains. Dans ce but, le nouveau modèle de fragmentation du grain proposé par Toth et al. a été utilisée. L'affinement du grain améliore les résultats de simulation texture de façon significative et donne des informations complémentaires sur la distribution et la taille moyenne des grains, et la distribution de désorientation qui peut être directement comparés aux résultats expérimentaux<br>The new severe plastic deformation (SPD) technique, designated as high pressure tube twisting (HPTT), is a continuous process for grain refinement in bulk metallic materials with tubular geometry. It consists of placing a mandrel into the tube before applying an axial compression directly on the tube confined on both sides to produce high hydrostatic pressure. The tube is then twisted by an external torque with the help of the friction force genrated by the hydrostatic pressure. The ultra-fine grained structures produced with HPTT were confirmed using transmission electron microscopy and their microstructure and mechanical properties were evaluated. The value of yield stress is increased monotonically with the deformation imposed by HPTT. Meanwhile, the inverse deformation path is proved to be less advantageous. Microstructural evolution is studied by EBSD technique and texture measurements were carried out using X-ray. Deformed samples have simple shear texture with relatively low intensities and the effect of the initial texture on the final texture persists up to shear strain of nearly 6. Grain-to-grain misorientation distribution functions are bimodal and the second pick become higher with increasing strain. Industrial application of this new SPD technique requires advanced modelling in terms of texture evolution and grain fragmentation process. For this purpose, the new grain refinement model proposed by Toth and al. was used. Grain refinement improves the texture simulation results significantly and gives information on the average grain size, grain size distribution and misorientation distribution function that can be directly compared to experimental results
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Bajwa, Gurjit Singh. "A study of the interaction of salts and model drugs with HPMC." Thesis, University of Nottingham, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.485463.
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Hydroxypropyl methylcellulose (HPMC) is frequently used as a rate control polymer in sustained release hydrophilic matrices. Certain salts and commercial drugs can alter the physiochemical properties ofHPMC and the performance of sustained release matrices. To aid formulation development an understanding of the interaction between the polymer and additives is crucial. (, Near-infrared spectroscopy was used to examine the effect of salts on the structure of water. Salts can alter the structure of water in a manner analogous to temperature. The influence of anions on the solubility ofHPMC appears to result from their ability to restructure water. ATR-FTIR spectroscopy and oscillatory rheology were used to examine the sol:gel transition of HPMC solutions at elevated temperatures. The spectroscopy study revealed evidence of increased hydrophobic methyl interactions during the phase transition. Pre-gelation changes in the elastic properties of the polymer solution were detected in the rheological study, these were ascribed to the progressive ' disruption of native cellulosic 'bundles'. The model NSAIDs studied (mefenamic acid, meclofenamate sodium, and flufenamic acid), increased the aqueous solubility of HPMC, probably by forming micelles at elevated concentrations, into which hydrophobic regions of the polymer solubilise. An interaction between HPMC and the carboxylate ion of the NSAIDs was detected in the ATR-FTIR study, this may account for the changes observed in the physiochemical properties ofthe polymer. A confocal scanning laser microscopy method was developed, utilising the fluorophore Congo Red, to monitor the critical early stages of gel layer formation around hydrating HPMC matrices. In the presence of 0.75 M sodium chloride the polymer particles clearly failed to form a coherent gel layer, and so accelerating the disintegration of the formulation.
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Thompson, Simon. "The study of HPRT gene expression using gene targeting and transgenic mice." Thesis, University of Edinburgh, 1989. http://hdl.handle.net/1842/13115.
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Carvalho, Rafael Aquino de. "Uma análise comparativa de ambientes para Big Data: Apche Spark e HPAT." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/45/45134/tde-15062018-110116/.
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Este trabalho compara o desempenho e a estabilidade de dois arcabouços para o processamento de Big Data: Apache Spark e High Performance Analytics Toolkit (HPAT). A comparação foi realizada usando duas aplicações: soma dos elementos de um vetor unidimensional e o algoritmo de clusterização K-means. Os experimentos foram realizados em ambiente distribuído e com memória compartilhada com diferentes quantidades e configurações de máquinas virtuais. Analisando os resultados foi possível concluir que o HPAT tem um melhor desempenho em relação ao Apache Spark nos nossos casos de estudo. Também realizamos uma análise dos dois arcabouços com a presença de falhas.<br>This work compares the performance and stability of two Big Data processing tools: Apache Spark and High Performance Analytics Toolkit (HPAT). The comparison was performed using two applications: a unidimensional vector sum and the K-means clustering algorithm. The experiments were performed in distributed and shared memory environments with different numbers and configurations of virtual machines. By analyzing the results we are able to conclude that HPAT has performance improvements in relation to Apache Spark in our case studies. We also provide an analysis of both frameworks in the presence of failures.
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Hsu, Stephen K. "Characterization of HPRT-deficient neuronal development in the human NTera2 differentiation model." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2008. http://wwwlib.umi.com/cr/ucsd/fullcit?p1459887.
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Thesis (M.S.)--University of California, San Diego, 2008.<br>Title from first page of PDF file (viewed January 5, 2009). Available via ProQuest Digital Dissertations. Includes bibliographical references (p. 30-32).
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Pezzini, Bianca Ramos. "Estudo comparativo e caracterização físico-química de matrizes de HPMC contendo captopril." Florianópolis, SC, 2001. http://repositorio.ufsc.br/xmlui/handle/123456789/81426.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências da Saúde. Programa de Pós-Graduação em Farmácia<br>Made available in DSpace on 2012-10-19T03:42:07Z (GMT). No. of bitstreams: 0Bitstream added on 2014-09-25T19:43:06Z : No. of bitstreams: 1
182936.pdf: 7758221 bytes, checksum: b00393eb2dcd1e076cda8c1918db11f7 (MD5)<br>O captopril é um inibidor da ECA, indicado para o tratamento da insuficiência cardíaca e da hipertensão. Como é prescrito para doentes crônicos, uma melhor adesão ao tratamento e uma diminuição no risco de efeitos indesejáveis poderiam ser obtidas se formas farmacêuticas com liberação prolongada contendo o fármaco fossem desenvolvidas. Neste trabalho, quatro formulações de matrizes hidrofílicas de HPMC contendo captopril foram propostas, com o objetivo de prolongar a liberação do fármaco. Uma formulação com liberação imediata foi produzida para ser usada como referência comparativa nos ensaios de dissolução. Objetivou-se a caracterização dos sistemas propostos, através das metodologias de DSC, DRX, MEV e de um estudo qualitativo de intumescimento. A análise estatística dos resultados de dissolução (ANOVA) comprovou que a formulação 4 manteve a liberação do fármaco por um maior período de tempo. Os resultados de DSC revelaram uma diminuição do índice de cristalinidade do fármaco nas formulações, em comparação com a substância pura. Os difratogramas de raios-X demonstraram modificação do comportamento cristalino do captopril, quando nas formulações. As fotomicrografias obtidas permitiram a caracterização da estrutura interna das matrizes. O estudo qualitativo de intumescimento confirmou o comportamento de formação de gel na superfície das matrizes, quando expostas ao meio aquoso.
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Dallol, Ashraf Rizk. "Genetic modifications of cytoplasmic thymidine kinase activity and the possible consequences on mutagen sensitivity." Thesis, University of Ulster, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326326.
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Rosales, Marc. "Study of SiGe HPT for radio over fiber applications." Thesis, Paris Est, 2014. http://www.theses.fr/2014PEST1101/document.
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Ce travail de thèse présente le développement de phototransistors bipolaires à hétérojonction (HPT) SiGe/Si mis en œuvre dans une technologie de processus 80GHz SiGe bipolaire pour des applications de transmission Radio-sur-Fibre. Le cas particuliers d'un réseau domestique sans fil à infrastructure optique est considéré pour lequel le critère de coût est prépondérant. Le fonctionnement des ce HPT SiGe/Si est étudié sous une longueur d'onde optique de 850 nm en exploitant des fibres optique multimode (MMF) suffisantes pour les besoins de bande passante dans un environnement de réseau domestique. Le HPT SiGe/Si est également développé dans l'objectif de permettre une intégration combiné du photorécepteur et circuit intégré monolithiquement, conduisant à des structures de type Opto-electronic Microwave Monolithically Integrated Circuit (OE-MMIC), visant à poursuivre l'intégration et la réduction des cours. Deux topologies ont été explorées principalement: 1) une topologie avec élargissement de la base et du collecteur (xBC HPT) et 2) une topologie avec élargissement des trois régions de base, émetteur et collecteur simultanément (xEBC HPT). Des variations technologies ont été réalisées et analysées en détail, à la fois en terme de couches verticales que de dessin de masque (layout). Les mesures ont démontré la validité technologique de chacune de ces approches, et permis d'isoler l'impact sur les performances statiques et dynamiques de chacune de ces couches. Une solution de type xEBC se montre ainsi préférable pour le cas de composants de petites dimensions inférieure à 50x50µm², dans la bande du GHz. Les phototransistors sont développés dans une configuration à trois terminaux (3T-HPT). Le type de polarisation de la base du HPT influe également sur la responsivité du phototransistor. Une polarisation de courant constant (CC) démontre une plus grande responsivité par rapport au cas d'une polarisation en tension ( CV). Une analyse détaillée montre aussi les différences de responsivité mesurées en continue et celles mesurées en basse fréquence à 50MHz. La connexion de base permet également de varier l'impédance de charge présentée sur celle-ci. La théorie de l'adaptation des phototransistors est rappelée. L'effet de différentes impédances de base sont étudiées par la simulation et la mesure des circuits réalisés technologiquement. L'intégration du phototransistor au sein d'un circuit élémentaire est enfin explorée. Différentes configurations de paires HPT - HBT sont étudiées, formant des circuits élémentaires. Des caractérisations expérimentales permettent de vérifier l'amélioration apportées par ces topologies par rapport au phototransistor unique. Enfin, un phototransistor SiGe en configuraiton 2T-HPT est utilisé et intégré avec succès pour la première fois au sein d'un module de type Receiving Optical Sub Assembly (ROSA) pour la mise au point d'une transmission Radio-sur-Fibre multiGigabit par seconde pour un réseau domestique<br>This research is focused on the study of silicon germanium based heterojunction bipolar phototransistors (SiGe HPTs) implemented in an 80GHz SiGe Bipolar process technology. It's application in a radio over fiber system for home area networks are investigated. RoF for Home area networks are envisioned to implemented with a minimal system cost. Operation at 850nm is identified as a critical parameter to achieve this goal. Low cost off the shelf optical components are readily available at this wavelength. The use of multi mode fibers (MMF) as opposed to higher cost single mode fiber (SMF) is sufficient for the bandwidth requirements in a home network environment. A monolithically integrated OE receiver chip would help in the overall reduction of the system cost by having the optical detector in the same chip with the electronic circuits. We have designed and implemented three terminal HPT (3T-HPT) structures. The two main groups of the HPT structures are: 1) HPTs with extended Base and Collector regions (xBC HPT) and 2) HPTs with extended Emitter, Base and Collector regions (xEBC HPT). Variations to improve optical coupling the though optimizations in the vertical stack and lateral size of the HPT. The measurements and characterization showed that all the structures are compatible with the process technology. The type of biasing used in the base of the HPT also influences the HPT performance. A constant current (CC) bias has higher extracted DC responsivity as compared to a constant voltage (CV) bias. The effects of the different passive base loads on the HPT responsivity are studied through simulation and measurement of fabricated circuits. The impedance presented on the base has a great influence on the HPT responsivity. The performance of an HPT as circuit component is studied using different HPT-HBT pair configurations. Tests and measurements verify that improvement in the classical transistor pair configurations are also present in the opto microwave response of the HPT-HBT pair. Finally, SiGe hpt is used in the development of a ROSA module for a radio over fiber systems for home area network
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Ugwu, Ignatius Obinna. "Cement fatigue and HPHT well integrity with application to life of well prediction." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-2351.
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Österholm, Anne-May. "Mutation profile at the HPRT locus in T-cells of non-smoking males /." Stockholm, 1998. http://diss.kib.ki.se/search/diss.se.cfm?19980605oste.
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Hackman, Peter. "HPRT mutational spectra and microsatellite DNA instability in HNPCC and lung cancer patients /." Stockholm, 2000. http://diss.kib.ki.se/2000/91-628-4219-6/.
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Morris, Tracy. "Molecular analysis of mutations at the hprt locus in primary human fibroblast lines." Thesis, Open University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314815.
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Tappertzhofen, Kristof G. [Verfasser]. "Funktionelle HPMA-Copolymere zur möglichen Anwendung in der Tumor-Immuntherapie / Kristof G. Tappertzhofen." Mainz : Universitätsbibliothek Mainz, 2015. http://d-nb.info/1065466811/34.
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Tritt-Goc, Jadwiga, and Joanna Kowalczuk. "MRI study of Fickian, case II and anomalous diffusion of solvents into HPMC." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-197112.
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Tritt-Goc, Jadwiga, and Joanna Kowalczuk. "MRI study of Fickian, case II and anomalous diffusion of solvents into HPMC." Diffusion fundamentals 2 (2005) 135, S. 1-2, 2005. https://ul.qucosa.de/id/qucosa%3A14481.
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Nilsson, Tony. "Investigation of Limiters For HPM and UWB Front-door Protection." Thesis, Linköping University, Department of Electrical Engineering, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-7836.
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<p>An extensive investigation of front-door protection devices i.e. limiters has been made. The thesis work contains both HPM- and UWB-measurements done on various limiters, in order to characterize them. The measurements show that all limiters are not suitable as protection against HPM- and UWB-pulses. The limiters that were found to provide the best protection are limiters based on diode technologies. PIN- and Schottky-diodes generally shows very good performance and they fulfill many parameters that have been set by FOI. To obtain a full protection it is presumably necessary to use two or more limiters in combination, which complement each other.</p><br><p>En omfattande studie av framvägskopplingsskydd, dvs. limiters har gjorts. Examensarbetet innehåller resultat från både HPM- och UWB- mätningar som har gjorts på olika limitrar för att karaktärisera deras prestanda. Av resultaten från mätningarna kan man se att alla limitrar inte passar som skydd mot HPM- och UWB-pulser. De limitrar som tillhandahöll det bästa skyddet var baserade på olika diodtekniker. PIN- och Schottky-dioder visade sig överlag ha väldigt goda prestanda och de uppfyller många av de parametrar som bestämts av FOI. För att få ett heltäckande skydd är det förmodligen nödvändigt att man använder två eller flera limitrar i kombination, som kompletterar varandra.</p>
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Klint, Andreas. "En ny motmedelsprincip : Kan HPM användas som motmedelssystem för helikopterplattformar?" Thesis, Försvarshögskolan, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:fhs:diva-6758.
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Denna studie undersöker ifall man i framtiden skulle kunna använda High Power Microwaves (HPM) som skyddssystem på helikopterplattformar. Skulle HPM kunna slå robotsystem på det elektroniska djupet istället för att avhaka eller blända hotsensorn, vilket idag görs med hjälp av facklor eller remsor. Uppsatsen beskriver funktion och ingående komponenter för HPM-konstruktioner, olika verkansformer samt skydd mot elektromagnetisk strålning. En beskrivning av hotrobotars olika delar och hur HPM påverkar dess funktioner ges. Ett scenario utarbetas för att skapa ett fast utgångsläge för SWOT-analys och beräkningar av ett HPM-baserat motmedelssystem. Scenariot är gjort för att skapa sämsta tänkbara läge för en helikopterplattform. Uppsatsen jämför även HPM-teknik med Directed Infrared Counter Measures (DIRCM), vilket är ett relativt nytt elektrooptiskt motmedel för skydd av helikoptrar mot IR-robotar. Efter jämförelsetabell och SWOT-analys forstätter studiens fokus vara HPM. Slutsatsen visar att det, av vikt-, volym-, uteffekt- och tidsskäl i en nära framtid inte lämpar sig att slå robotsystem på det elektroniska djupet för att skydda en mindre helikopterplattform mot hotrobotar. HPM- system lämpar sig däremot väl för rörligare större plattformar som TP84. HPM-teknik på helikopter visar sig emellertid kunna nyttjas som verkans- och Understödssystem för skydd av större geografiskt område, vid förflyttning eller som telekrigsunderstöd av markförband, vilket möjliggörs av helikopterns höga rörlighet.
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CINQUE, LUIGIA. "Multi-integrated approach based on HPT-JT families for the identification of a set of biomarkers of Parathyroid Carcinoma." Doctoral thesis, Università di Foggia, 2018. http://hdl.handle.net/11369/369205.
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Introduzione. Nella sindrome da iperparatiroidismo associato a tumore della mandibola (HPT-JT), il carcinoma paratiroideo (PC) è causato da mutazioni del gene oncosoppressore CDC73 codificante per parafibromina, un componente del complesso PAF1 coinvolto nel rimodellamento della cromatina e nella regolazione del ciclo cellulare. Le mutazioni del gene MEN1 causano la sindrome omonima (MEN1), le cui lesioni paratiroidee sono benigne nel 99% dei casi ma, negli ultimi 40 anni, sono stati riportati 15 casi di associazione insolita fra PC e la sindrome MEN1 nel mondo. Il PC è un tumore raro e aggressivo per il quale le attuali terapie sono risultate inefficaci e l'asportazione chirurgica della lesione rimane l'unico approccio curativo. Tuttavia, la distinzione in prima diagnosi fra una lesione paratiroidea maligna e un’ iperplasia indolente o un’adenoma benigno rappresenta ancora oggi una sfida, in assenza di segni patognomici, come metastasi a distanza o recidive locali. Finora, sono stati compiuti sforzi infruttuosi per la ricerca di biomarcatorimolecolari che potessero indirizzare verso il (migliore) trattamento chirurgico (conservativo/demolitivo) al fine di ridurre il rischio di recidiva e di estendere la sopravvivenza libera da malattia. Scopo del progetto e metodi. Questo progetto mira a identificare le cause genetiche che portano allo sviluppo di un carcinoma paratiroideo (PC) e a individuare una serie di biomarcatori utili per una inequivocabile e precoce diagnosi di PC. A tal fine sono state applicate strategie di Next Generation Sequencing, quali il sequenziamento dell’ intero esoma e studi di espressione genica, a casi familiari (costituiti da uno o più soggetti affetti, portatori non affetti e controlli sani con lo stesso background genetico) piuttosto che a casi sporadici al fine di ridurre, per quanto possibile, la variabilità intrinseca causata dai diversi background genetici. La nostra rara coorte consta di 5 famiglie con HPT-JT e lesione paratiroidea maligna e mutazione costituzionale del gene CDC73 e una famiglia molto rara con mutazione MEN1 associata a PC. Risultati. Il sequenziamento dell’intero esoma ha mostrato che solo i soggetti affetti di 4 (delle 5) famiglie con HPT-JT reclutate per lo studio, condividono varianti rare (MAF <0,004) in geni codificanti per le integrine (ITGA3, ITGA2B, ITGA11, ITGAB6, ITGA9), recettori di superficie coinvolti nell'adesione cellulare alla matrice extracellulare (ECM) ed essenziali per la proliferazione, la sopravvivenza, l'adesione e la migrazione delle cellule. Inoltre sono state identificate ulteriori varianti nei geni che codificano per proteine coinvolte nel riparo del DNA come FANCC e BRIP1; NOTCH4; RET; BRCA1; BLK; MUC12; KMT2C; geni target della pathway di Hedgehog quali SMO, GLI3, mentre una variante del gene GLI2 è stata identificata solamente nei soggetti affetti della famiglia MEN1 associata a PC. Lo studio dell’ espressione genica è stato condotto confrontando i pazienti affetti vs controlli fra le famiglie con HPT-JT e l'unica famiglia MEN1-PC. L’ analisi effettuata ha mostrato un'espressione differenziale dei geni del sistema immunitario e inoltre ha evidenziato che i pazienti MEN1 e HPT-JT utilizzano diversi set di geni per controllare la mobilizzazione del calcio. Saggi funzionali. Cellule HEK293 sono state trasfettate con vettori di espressione codificanti la forma WT o mutata del gene CDC73: sono state testate 5 diverse mutazioni in presenza/assenza di Bortezomib, un farmaco già utilizzato in clinica per la terapia del mieloma multiplo. Questo inibitore del proteasoma sembra essere in grado di recuperare parzialmente l'espressione di proteine CDC73 mutate a causa di mutazioni missenso, in-frame e persino frameshift. Conclusioni e prospettive. Questo progetto, seppur preliminare, può aiutarci ad identificare biomarker utili per una diagnosi precoce e immediata di PC al fine di indirizzareverso il miglior approccio chirurgico e identificare i portatori asintomatici nelle famiglie affette per un intervento precoce ed efficace. Ipotizziamo che l'insorgenza/progressione/aggressività del PC possa essere dovuta alla deregolazione di proteine coinvolte nell'adesione cellula-cellula (come le integrine); allo squilibrio nell’ attivazione del sistema immunitario; alla deregolazione della pathway di Hedgehog e alla perdita di fattori scatenanti, come le proteine implicate nel mantenimento dell'integrità del DNA (FANCC, BRIP1, BRCA1). Infine, considerando che la ricerca di un farmaco efficace come approccio alternativo al trattamento chirurgico è risultata fino ad oggi vana, per la prima volta, riportiamo il possibile utilizzo di un farmaco chemioterapico ben conosciuto, il Bortezomib, per la terapia del PC dovuto a mutazioni del gene CDC73.<br>Background. As part of the Hyperparathyroidism with Jaw Tumor syndrome (HPT-JT), parathyroid carcinoma (KP) is caused by mutations of the CDC73 tumor suppressor gene, encoding the parafibromin, a PAF1 co-transcription factor, involved in chromatin remodelling and cell cycle regulation. Mutations of MEN1 gene cause the namesake syndrome (MEN1), in whose parathyroid lesions are benign in 99% of cases: instead, in the last 40 ys, only 15 cases worldwide have been reported with the unusual association of KP in MEN1 syndrome. KP is a rare, aggressive life-threatening tumor for whose at the present current therapies resulted ineffective and the surgical removal of the lesion remains the only curative approach. However, to recognize in first diagnosis a malignant parathyroid lesion from an indolent hyperplasia or benign adenoma still represents a challenge, in absence of pathognomic signs, such as distant metastasis or local recurrences. So far, unsuccessful efforts have been made in search of clinical biomarkers that could address to the (best) surgery option (conservative/demolitive) in order to reduce the risk of recurrence and to extend the disease free survival. Purpose and methods. The present project aims to identify the genetic causes leading to the development of a parathyroid carcinoma (KP) and to detect a set of biomarkers for a possible unequivocal, early first diagnosis. We decided to apply high throughput strategies such Whole Exome Sequencing (WES) and Expression Profiling (EP) to familial cases (consisting of one or more affected subjects, non-affected carriers and healthy controls with the same genetic background) rather than to sporadic ones in order to, possibly, reduce the intrinsic variability caused by different genetic backgrounds. Our rare cohort consisted of 5 HPT-JT families with malignant parathyroid lesion and constitutional mutation of the CDC73 gene and a very rare family with MEN1 mutation associated with recurrent and familial KP. Results.WES analysis revealed that in 4 (out of 5) HPT-TJ families, surprisingly, only the affected subjects shared rare variants (MAF < 0.004) in genes encoding the integrins (ITGA3, ITGA2B, ITGA11, ITGAB6, ITGA9), cell surface receptors involved in cell adhesion to the extracellular matrix (ECM) and essential for proliferation, survival, adhesion and migration of cells. Moreover, other variants in genes encoding proteins involved in DNA repair such as FANCC and BRIP1; NOTCH4; RET; BRCA1; BLK; MUC12; KMT2C; Hedgehog target genes such as SMO, GLI3 were identified. Finally a variant in GLI2 gene was found inaffected subjects of MEN1- KP family. The EP analysis compared the affecteds vs controls between HPT-JT families and the unique MEN1-KP family. The analysis showed a differential expression of genes of immune system. The EP also evidenced that MEN1 and HPT-JT patients use different set of genes to control the calcium mobilization. Functional assay. Human embryonic kidney (HEK293) cell lines were transfected with eukaryotic expression vectors carrying WT or mutated CDC73 gene: 5 different mutations weretested in presence/absence of Bortezomib, a drug already used in clinic for the therapy of multiple mieloma. We proved that this proteasome inhibitor was able to partially rescue the expression of missense, inframe and even frameshift CDC73 gene deletions. Conclusions and perspectives. This preliminary project may help to find a biomarkers set for a prompt early diagnosis of KP, in order to suggest the best surgical approach and identify asymptomatic carriers in affected families for an efficient early intervention. We suppose that the onset/progression/aggressivity of KP may be due to the deregulation of proteins involved in cell-cell adhesion (such integrins); the derangement of immune system; the deregulation of the Hedgehog pathway and the lack of trigger factors, such as the proteins assigned to DNA integrity (FANCC, BRIP1, BRCA1). Finally we reported, for the first time, the possible use of a well known chemotherapy drug, the Bortezomib, for the therapy of KP CDC73 induced, taking into account that, so far, all the attempts to find an efficient drugs as alternative approach to the surgery, resulted ineffective.
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Caceres, Najarro Marleny. "Depolymèrization enzymatique d’Hydroxypropyl Methyl Cellulose (HPMC) pour la conception des nouveaux copolymères à blocs." Thesis, Montpellier, Ecole nationale supérieure de chimie, 2015. http://www.theses.fr/2015ENCM0027/document.
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Parmi les bio-polymères issus des ressources renouvelables, les polysaccharides fournissent une alternative intéressante aux polymères de synthèse. Dans ce contexte, l’objectif de ce travail de thèse est basé sur la conception des copolymères amphiphiles pour la préparation de nouveaux biomatériaux. Ainsi, l’hydroxypropylméthylcellulose (HPMC) a été étudiée en raison de ses propriétés remarquables, dont la biocompatibilité, la biodégradabilité, la rétention d'eau et la gélification thermoréversible. Ces propriétés sont utiles pour de nombreuses applications telles que le relargage de médicament, la préparation des membranes et la formation de biomatériaux. L'hydrolyse enzymatique avec des endo cellulases issues de Trichoderma reesei a été étudiée pour produire des fragments d'HPMC ayant une masse molaire (Mw) entre 6000 et 30000 g mol-1. Les paramètres de l’activité enzymatique ont été étudiés en fonction de : la nature de substrat, le temps de réaction et la concentration de l'enzyme. Les polymères obtenus ont été comparés à ceux produits par hydrolyse acide. Il a été constaté que la structure des polymères issus d’un procédé d’hydrolyse, varie en termes de degré de substitution pour un même Mw. Cet effet donne lieu à différentes propriétés de gélification thermoréversible. Des copolymères amphiphiles tels que HPMC-b-poly (propylène glycol) et HPMC-b-PLA ont été préparés par amination réductrice et par couplage click thiol-ene, respectivement. Les propriétés d’agrégation ont été caractérisées par la diffusion de la lumière (DLS), le microscope électronique en transmission (TEM) et par la séparation de phase obtenue par la mesure du point de trouble<br>Following the concept of bio-refinery, we propose to produce small fragments of biopolymers that can be used further as building blocks to prepare novel polymeric architectures. In the case of polysaccharides, enzymatic hydrolysis enables to form reducing end groups after each cleavage on the polymer chain. Reaction by reductive amination affords the possibility to introduce polysaccharides fragments in a large variety of materials going from amphiphilic copolymers to more sophisticated devices. Hydroxypropyl methylcellulose (HPMC) was used in this work because of its remarkable properties including biocompatibility, biodegradability, water retention and thermoreversible gelation beneficial for many applications such as drug delivery, film and biomaterial formation. Enzymatic hydrolysis using endo cellulases from Trichoderma reesei was investigated to produce a library of HPMC fragments with molecular weight (Mw) from 6000 to 30000 g mol-1. Mw control was carried out by varying the procedure conditions including the nature of starting HPMC, reaction time and enzyme concentration. The obtained polymers were compared to those produced by acidic hydrolysis.According to the preparation conditions, the structure of short chain polymers regarding substitution degrees varied for the same Mw giving rise to different clouding temperature and thermoreversible gelation properties. Amphiphilic block copolymers HPMC-b-poly(propylene glycol) and HPMC-b-PLA were prepared by reductive amination and by the thiol-ene click reaction, respectively. Self-assembly properties of these novel block copolymer were characterized by dynamic light scattering (DLS), transmission electron microscope (TEM), and clouding point temperature
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Quaglio, Ana Elisa Valencise [UNESP]. "HSP70, heparanase e HPRT participam da resposta inflamtória intestinal induzida por TNBS em ratos." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/91646.
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quaglio_aev_me_botib.pdf: 425313 bytes, checksum: 2483f9db556c10ebc5c1a2db7f971fa3 (MD5)<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)<br>A Doença Inflamatória Intestinal (DII) engloba, fundamentalmente, duas doenças distintas: a Doença de Crohn (DC) e a Retocolite Ulcerativa (CU), ambas caracterizadas por uma inflamação crônica do intestino, com períodos de exacerbação seguidos de intervalos prolongados de remissão dos sintomas. Apesar da DII ser objeto de pesquisa há várias décadas, a sua etiologia ainda é desconhecida e a principal limitação no entendimento dos mecanismos fisiopatológicos desta doença é a disponibilidade de modelos experimentais adequados que mimetizem o caráter crônico e de recidiva da DII em humanos e que possam ser de baixo custo, reprodutível, fácil de induzir e que apresente características clínicas e histopatológicas, respostas terapêuticas e mediadores inflamatórios similares ao que ocorre com a doença em humanos. Dentre os vários modelos experimentais disponíveis, o modelo de colite induzida por ácido trinitrobenzenosulfônico (TNBS) em ratos tem sido considerado o mais adequado para a avaliação de novos fármacos, assim como aquele que melhor mimetiza esta doença em humanos. Assim sendo, a caracterização do papel de diferentes mediadores do processo inflamatório intestinal neste modelo permitiria a determinação de novos alvos terapêuticos, assim como geraria informações importantes da fisiopatologia desta doença. Neste sentido, o presente projeto teve como objetivo determinar a participação da HSP70, Heparanase e HPRT, mediadores do processo inflamatório intestinal em humanos, na fase aguda do processo inflamatório intestinal induzido TNBS em ratos, assim como estudar os efeitos de fármacos das três principais classes farmacológicas usadas no tratamento da DII em humanos, os aminossalicilatos (sulfassalazina), os glicocorticóides (prednisolona) e os imunomoduladores (azatioprina) sobre esses mediadores. Este estudo demonstrou que HSP70, Heparanase...<br>The idiopatic inflammatory bowel diseases comprise two types of chronic intestinal disorders: Crohn’s disease and ulcerative colitis that are characterized by a chronic inflammation of the intestine, with periods of remission and reactivation of the inflammatory process. Although IBD is the subject of research for several decades, its etiology remains unknown, and the major limitation to understanding the IBD pathophysiology is the availability of experimental models that mimic the chronic and relapse of human IBD. Is still important that experimental models can be inexpensive, reproducible, easy to induce and present clinical and histopathological features, therapeutic responses and inflammatory mediators similar to what occurs in humans. Among experimental models available, the model of colitis induced by trinitrobenzenesulphonic acid (TNBS) in rats has been considered the most suitable for the evaluation of new drugs, as well as the one that best mimics the disease in humans. Therefore, the involvement of different IBD mediators in this experimental model would allow the determination of new therapeutic targets, as well as generate important information on the pathophysiology of this disease. In light of this, the aim of present study was to determine the participation of HSP70, Heparanase and HPRT, mediators of intestinal inflammatory process in humans, in acute phase of inflammatory process induced by TNBS in rats, as well as, to study the effects of drugs of the three main classes used in the treatment of human IBD, i.e., aminosalicylates (sulphasalazine), glucocorticoids (prednisolone) and immunomodulators (azathioprine) on these mediators. This study showed that HSP70, Heparanase and HPRT participate as mediators of intestinal inflammation induced by TNBS since these mediators are increased in colitic animals when compared to healthy animals... (Complete abstract click electronic access below)
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Costello, Patrick Sean. "The role of 5' and 3' sequences in the control of HPRT gene expression." Thesis, University of Edinburgh, 1993. http://hdl.handle.net/1842/13476.
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The mammalian HPRT gene is a housekeeping gene. It is expressed constitutively at a low level in all cell types with the exception of the brain where expression is elevated. It has been shown in human brains that HPRT expression is particularly high in the basal ganglia. Total HPRT deficiency in man is the cause of Lesch-Nyhan syndrome, a severe neurological disorder. Partial HPRT deficiency leads to gouty arthritis. In the mouse it has been shown that the elevated level of HPRT activity in the brain is accompanied by an elevation in the steady state level of HPRT mRNA. The aim of the work presented in this thesis was to elucidate the mechanism of this elevation. The role of both 5' and 3' sequences has been explored. Expression of the mouse HPRT gene in cultured cells has identified promoter elements essential for a basal level of transcription. This work has been extended to animals by using gene targeting in embryonic stem cells. A HPRT mutant gene has been corrected by gene targeting, introducing a 35 bp core promoter which is capable of directing expression in cell culture. This has enabled the minimal elements of the promoter sequence to be identified which can direct brain specific elevation <i>in vivo</i>. The role of the 3' untranslated region (UTR) in determining tissue specific elevation of expression has also been investigated. The possibility that differential polyadenylation might be responsible has been excluded. Gene targeting has been used to substitute the native 3' UTR with the 3' UTR of the human growth hormone gene. This has demonstrated the potential of gene targeting as a way of manipulating the mammalian genome to study the expression of endogenous genes.
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Quaglio, Ana Elisa Valencise. "HSP70, heparanase e HPRT participam da resposta inflamtória intestinal induzida por TNBS em ratos /." Botucatu : [s.n.], 2011. http://hdl.handle.net/11449/91646.
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Orientador: Luiz Claudio Di Stasi<br>Banca: Marcelo Fabio Gouveia Nogueira<br>Banca: Alessandra Gambero<br>Resumo: A Doença Inflamatória Intestinal (DII) engloba, fundamentalmente, duas doenças distintas: a Doença de Crohn (DC) e a Retocolite Ulcerativa (CU), ambas caracterizadas por uma inflamação crônica do intestino, com períodos de exacerbação seguidos de intervalos prolongados de remissão dos sintomas. Apesar da DII ser objeto de pesquisa há várias décadas, a sua etiologia ainda é desconhecida e a principal limitação no entendimento dos mecanismos fisiopatológicos desta doença é a disponibilidade de modelos experimentais adequados que mimetizem o caráter crônico e de recidiva da DII em humanos e que possam ser de baixo custo, reprodutível, fácil de induzir e que apresente características clínicas e histopatológicas, respostas terapêuticas e mediadores inflamatórios similares ao que ocorre com a doença em humanos. Dentre os vários modelos experimentais disponíveis, o modelo de colite induzida por ácido trinitrobenzenosulfônico (TNBS) em ratos tem sido considerado o mais adequado para a avaliação de novos fármacos, assim como aquele que melhor mimetiza esta doença em humanos. Assim sendo, a caracterização do papel de diferentes mediadores do processo inflamatório intestinal neste modelo permitiria a determinação de novos alvos terapêuticos, assim como geraria informações importantes da fisiopatologia desta doença. Neste sentido, o presente projeto teve como objetivo determinar a participação da HSP70, Heparanase e HPRT, mediadores do processo inflamatório intestinal em humanos, na fase aguda do processo inflamatório intestinal induzido TNBS em ratos, assim como estudar os efeitos de fármacos das três principais classes farmacológicas usadas no tratamento da DII em humanos, os aminossalicilatos (sulfassalazina), os glicocorticóides (prednisolona) e os imunomoduladores (azatioprina) sobre esses mediadores. Este estudo demonstrou que HSP70, Heparanase... (Resumo completo, clicar acesso eletrônico abaixo)<br>Abstract: The idiopatic inflammatory bowel diseases comprise two types of chronic intestinal disorders: Crohn's disease and ulcerative colitis that are characterized by a chronic inflammation of the intestine, with periods of remission and reactivation of the inflammatory process. Although IBD is the subject of research for several decades, its etiology remains unknown, and the major limitation to understanding the IBD pathophysiology is the availability of experimental models that mimic the chronic and relapse of human IBD. Is still important that experimental models can be inexpensive, reproducible, easy to induce and present clinical and histopathological features, therapeutic responses and inflammatory mediators similar to what occurs in humans. Among experimental models available, the model of colitis induced by trinitrobenzenesulphonic acid (TNBS) in rats has been considered the most suitable for the evaluation of new drugs, as well as the one that best mimics the disease in humans. Therefore, the involvement of different IBD mediators in this experimental model would allow the determination of new therapeutic targets, as well as generate important information on the pathophysiology of this disease. In light of this, the aim of present study was to determine the participation of HSP70, Heparanase and HPRT, mediators of intestinal inflammatory process in humans, in acute phase of inflammatory process induced by TNBS in rats, as well as, to study the effects of drugs of the three main classes used in the treatment of human IBD, i.e., aminosalicylates (sulphasalazine), glucocorticoids (prednisolone) and immunomodulators (azathioprine) on these mediators. This study showed that HSP70, Heparanase and HPRT participate as mediators of intestinal inflammation induced by TNBS since these mediators are increased in colitic animals when compared to healthy animals... (Complete abstract click electronic access below)<br>Mestre
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Mariotti, Ludovic. "La réforme "Hôpital, patients, santé et territoires" : Une recomposition de l’action publique locale en trompe l’œil ? : Une analyse par les instruments au prisme du secteur médico-social en région Provence-Alpes-Côte d'Azur." Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTD032.
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La réforme « Hôpital, patients, santé et territoires » (HPST) de 2009 a positionné l’agence régionale de santé en tant que chef de file de la santé à l’échelle régionale. En mobilisant une approche par les instruments, notre thèse pose la question de la réalité de ce rôle de pilotage lors de la phase de sa mise en œuvre. En toile de fond, ce questionnement fait écho à une interrogation plus globale, à savoir : qui dirige la politique de santé au niveau local ? En investissant le secteur de la santé de la région Provence-Alpes-Côte d'Azur par l’angle original du secteur médico-social, notre analyse démontre que les instruments qui devraient être aux mains de l’ARS ne le sont qu’à la marge. Ainsi, chaque instrument, qu’il s’inscrive dans le sillon ancien de la planification ou qu’il relève d’une idéologie plus libérale nous donne à voir une répartition des compétences différente de celle initialement annoncée et légalement prévue. Concernant les instruments de la planification, une distinction s’opère entre ceux non financiers et ceux relevant de la répartition des crédits. Nous démontrons que, lorsque les instruments de planification à disposition de l’ARS présentent uniquement des aspects cognitifs, les organes de démocratie sanitaire créés par la Loi dispose d’une véritable marge de manœuvre à même d’influer sur son contenu. Les instruments adoptés de la sorte par l’ARS sont donc à la fois le fruit de la concertation entre acteurs de santé à l’échelle locale et témoignent d’une véritable capacité à agir de l’ARS sur ceux-ci. A contrario, dès lors que les instruments de planification revêtent une dimension financière, ils échappent à tout contrôle du niveau régional, l’ARS s’avère finalement inféodée au niveau national en la matière. Quant aux instruments au design proche de ceux du « new public management » (Appels à projets et contrats pluriannuel d’objectifs et de moyens notamment), la démonstration met en évidence une triple désubstantialisation de l’ARS. Par le haut, c’est-à-dire par un contrôle systématique et direct des instances nationales ; par le bas, l’ARS devant composer avec la fragmentation des institutions locales existantes sans disposer du dernier mot ; et par le musellement de la démocratie sanitaire locale dont les capacités sur ses instruments sont légalement et dans les faits réduites au minimum<br>The 2009 reform “Hôpital, patients, santé, territoires” (HPST) made the « Agence Régionale de Santé » the leading health organism on a regional level. By using an instrument approach, our thesis exanimates the reality of this role during its application. This question echoes a more global issue: namely, who are health policies decided by, on a local level?By investigating the health field within the PACA region, through the lenses of the medico-social area, our work demonstrate that the instruments supposedly in the hands of the ARS are only barely so. Each instrument, whether it finds its origins in the old healthcare planning ideal or in a more liberal ideology, let us discover a distribution of competences different from what is legally intended
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Nwulu, Equi Emmanuel. "Utility of the HPT Framework for Improving Distance Education in Nigeria." Thesis, Walden University, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10687499.
Full textAbstract:
<p> The fusion of the Internet with instructional design, and curricula delivery methods eliminated transactional distance in online learning. However, distance education (DE) in Nigeria has not aligned its pedagogy to the new reality in technology. The purposes of this non-experimental, predictive, validity study were to determine faculty and administrators’ perceived barriers and concerns to online adoption and to validate the behavior engineering model (BEM) instrument. Ninety-six respondents from four public universities in Nigeria completed the questionnaires. Descriptive statistics and structural equation modeling (SEM) were used respectively, to assess barriers and concerns militating against faculty and administrators’ online adoption, as well as validate the survey instruments. For faculty and administrators, incentive, motive, knowledge and skills influenced DE adoption. Except for age, all demographic factors influenced faculty’s concerns. Gender was observed to influence administrators’ concern. “Level of online use” influenced neither faculty nor administrators’ concerns. Technographic characteristics influenced faculty, but not administrators.’ Though the BEM instrument was reliable in measuring faculty and administrator’s stages of concern, however, the 6-factor BEM, tested at the 95% significant level, did not give a good fit. The study contributes to positive social change by identifying gaps to effective DE implementation, and recommended the appropriate interventions to transform the DE experience for students and their universities. The study also proposed the framework to fast track Nigeria’s vision and mission for DE.</p><p>
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Poloprudský, Jakub. "Struktura a mechanické vlastnosti materiálů na bázi hořčíku zpracovaných metodou HPT." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2019. http://www.nusl.cz/ntk/nusl-400834.
Full textAbstract:
This thesis is focused on processing of pure magnesium by high pressure torsion method (HPT). This process belongs to the group of intensive plastic deformation methods (SPD). SPD methods are in the centre of scientific interest for several decades. Theoretical part of this thesis puts an effort to summarize basic knowledge and principles of SPD methods with extra focus on method HPT. As theoretical part continues magnesium as technical material is presented. Influence of SPD on use and properties of pure magnesium is then presented. This trend is further developed in effort to describe the effect of individual HPT process variables on the properties of pure magnesium and its alloys. Focus of practical part of this thesis is in influence of number of revolutions. Samples were processed at 1/8, 1/4, 1/2, 1, 4 and 8 turns at room temperature. Speed of process was 1rpm and applied pressure was 6 GPa. The structure of commercially pure magnesium prepared by casting and moulding were observed with focus on differences caused by input material. The structure was observed by both light microscopy and back scattered electron diffraction (EBSD), focusing on structure development, grain size and grain orientation. Compared to other works on similar topic, the emphasis here is on observing the microhardness on the vertical edge of the sample. The hardness shows a steep increase right after 1/8 of a turn. With increasing number of turns gradual homogenization of microhardness is presented accompanied by slight decrease in microhardness. No trend in microhardness relative to the distance from anvil has occurred. Structure observed with EBSD shows a bimodal character with larger grains oriented in the same direction. The three-point bending test didn’t end up as expected, and the approach to evaluation of magnesium-based HPT needs to be re-evaluated for future work. A three-point bending test was designed for the initial assessment of the basic mechanical properties of the material.
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Nwulu, Equi. "Utility of the HPT Framework for Improving Distance Education in Nigeria." ScholarWorks, 2018. https://scholarworks.waldenu.edu/dissertations/4663.
Full textAbstract:
The fusion of the Internet with instructional design, and curricula delivery methods eliminated transactional distance in online learning. However, distance education (DE) in Nigeria has not aligned its pedagogy to the new reality in technology. The purposes of this non-experimental, predictive, validity study were to determine faculty and administrators' perceived barriers and concerns to online adoption and to validate the behavior engineering model (BEM) instrument. Ninety-six respondents from four public universities in Nigeria completed the questionnaires. Descriptive statistics and structural equation modeling (SEM) were used respectively, to assess barriers and concerns militating against faculty and administrators' online adoption, as well as validate the survey instruments. For faculty and administrators, incentive, motive, knowledge and skills influenced DE adoption. Except for age, all demographic factors influenced faculty's concerns. Gender was observed to influence administrators' concern. "Level of online use" influenced neither faculty nor administrators' concerns. Technographic characteristics influenced faculty, but not administrators.' Though the BEM instrument was reliable in measuring faculty and administrator's stages of concern, however, the 6-factor BEM, tested at the 95% significant level, did not give a good fit. The study contributes to positive social change by identifying gaps to effective DE implementation, and recommended the appropriate interventions to transform the DE experience for students and their universities. The study also proposed the framework to fast track Nigeria's vision and mission for DE.
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Markkula, Mikael. "Synthesis, structure and properties of high pressure and ambient pressure ternary vanadium oxides." Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/8061.
Full textAbstract:
Transition metal oxides have been extensively studied during past decades. The purpose of this research was to synthesize new or little characterised transition metal oxides using high-pressure/high-temperature (HPHT) techniques. Various ternary vanadium oxides have been synthesised at ambient and high pressure conditions. All compounds have been studied by neutron and laboratory X-ray powder diffraction and magnetisation measurements. In some cases resistivity and synchrotron X-ray powder diffraction measurements were also carried out. The MnVO3 perovskite containing localized 3d5 Mn2+ and itinerant 3d1 V4+ states has been synthesised at 8 GPa and 1100°C. MnVO3 crystallises in Pnma space group (a = 5.2741(6) Å, b = 7.4100(11) Å, and c = 5.1184(8) Å at 300 K) and is metallic at temperatures of 2 – 300 K and at pressures of up to 67 kbar. Synchrotron X-ray powder diffraction study on the combined sample of several high pressure products showed slight variation in the stoichiometry of MnVO3. Incommensurate Mn spin order was discovered in the neutron powder diffraction measurements, which reveal a (0.29 0 0) magnetic vector below the 46 K spin ordering transition, and both helical and spin density wave orderings are consistent with the diffraction intensities. Electronic structure calculations show large exchange splittings of the Mn and V 3d bands, and (kx 0 0) crossings of the Fermi energy by spin up and down V 3d bands may give rise to Ruderman-Kittel-Kasuya-Yosida coupling of Mn moments, in addition to their superexchange interactions. The new compound CoVO4 has been discovered in a high pressure synthesis experiment. Magnetic susceptibility measurement, synchrotron X-ray and neutron powder diffraction studies were carried out. Refinements of the synchrotron X-ray and neutron data show CoVO4 to crystallise in space group Pbcn (a = 4.5012(2) Å, b = 5.5539(3) Å, and c = 4.8330(2) Å at 300 K (synchrotron X-ray data)). The magnetic susceptibility measurement reveals that Co3+ is most likely in a low spin state in CoVO4. Monoclinic brannerite type CoV2O6 was synthesised in ambient pressure. Neutron powder diffraction measurements were carried out and an antiferromagnetic order with an a x b x 2c supercell was observed below TN = 15 K. High spin Co2+ moments of magnitude 4.77(4) μB at 4 K lie in the ac plane and are ferromagnetically coupled within chains of edge-sharing CoO6 octahedra parallel to b axis. No structural transition is observed down to 4 K, but a magnetostriction accompanying antiferromagnetic order at TN = 15 K was discovered. A field-induced 1/3 magnetisation plateau and corresponding changes in the magnetic structure were studied by carrying out neutron powder diffraction measurements at 2 K in applied magnetic fields of 0, 2.5 and 5.0 T. Three collinear magnetic phases were observed as field increases; the above antiferromagnetic state with propagation vector (0 0 ½), a ferrimagnetic (¯⅓ 1 ⅓) phase, and a (0 0 0) ferromagnetic order. Co2+ moments of 4.4 - 5.0 μB have a large orbital component and are aligned close to the c-axis direction in all cases. Spin-lattice coupling leads to a magnetostriction and volume expansion as field increases. The ferrimagnetic phase accounts for the previously reported 1/3 magnetisation plateau, and demonstrates that monoclinic CoV2O6 behaves as an accidental triangular antiferromagnetic lattice in which further frustrated orders may be accessible. Orthorhombic columbite-type NiV2O6 and CoV2O6 compounds were synthesised at 6 GPa and 900°C. Metamagnetism and magnetic transitions were found in magnetic measurements. Powder neutron diffraction studies in zero and applied field were carried out. Both compounds were refined in space group Pbcn and the following lattice parameters were obtained at 300 K, CoV2O6: a = 13.4941(20) Å, b = 5.5736(9) Å, and c = 4.8082(8) Å and NiV2O6: a = 13.3725(17) Å, b = 5.5344(7) Å, and c = 4.8162(7) Å. Neutron powder diffraction studies in zero field did not reveal any magnetic peaks for either of the compounds but magnetic order emerges in applied fields between 1 and 4 T.