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SIGIC/CTH - Levantamento de Processos no Hospital da PreladaLopes, Maria Cláudia Martins de Sousa dos Anjos January 2010 (has links)
Estágio realizado no Hospital da Prelada orientado pelo Engº. João Figueiredo / Documento confidencial. Não pode ser disponibilizado para consulta / Tese de mestrado integrado. Engenharia Industrial e Gestão. Faculdade de Engenharia. Universidade do Porto. 2010
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Interakce enzymů uvolňujících sulfan v prasečích oocytech během meiotického zrání / Interactions of Hydrogen Sulfide Releasing Enzymes in Porcine Oocytes during Meiotic MaturationJiříček Hasalová, Simona January 2016 (has links)
The reproductive biotechnologies currently represent a major scientific discipline based on a sufficient quantity of wholesome oocytes matured in vitro conditions to acquire permits for their effectiveness. The meiotic maturation is a complex process where a wide range of factors is involved in the regulation. One of these factors are small gaseous molecules, so-called gasotransmitters. These gases demonstrate number of physiological functions in the organism and the latest discovered gasotransmitter is hydrogen sulfide (H2S).
The aim of this thesis was to test the hypothesis according to which there are enzymes present in porcine oocytes that produce H2S (CBS, CTH, 3-MPST), their distribution is in interaction and their joint actions influence the process of the meiotic maturation. The resulting data were obtained on the basis of immunocytochemical staining and colocalization analysis.
The results proofed the presence of H2S-releasing enzymes in porcine oocytes. It was also confirmed the function of these enzymes in relation to the regulation of the meiotic maturation when oocytes cultured with triple inhibitors of H2S-releasing enzymes matured more slowly. The results also showed medium correlation dependence of enzymes CBS, CTH and 3-MPST. The combination of CBS and 3-MPST resulted in high correlation dependence which confirmed their interaction both in immature oocytes and in vitro matured oocytes.
It is evident that so far studied effects of H2S are only a fraction of skills which this signal molecule possesses. There exists a need for future experiments to help us describe and explain the acting mechanisms of H2S.
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Intracelulární distribuce enzymů uvolňujících sulfan ve zrajících oocytech prasete / Intracellular distribution of hydrogen sulfide releasing enzymes in maturing porcine oocytesVondráková, Veronika January 2016 (has links)
The study of the molecular mechanisms regulating reproductive processes is crucial for increasing the efficiency of reproductive biotechnologies that are often used in animal breeding. A key part of many biotechnological methods is the cultivation of oocytes, which simulates natural conditions in the ovaries. However this simulation is still imperfect and presents a limiting factor for successful formation of mammalian oocytes.capable of fertilization.
Meiotic maturation is influenced by many factors including for example gasotransmiter hydrogen sulfide (H2S). Until recently, hydrogen sulfide was known only as toxic gas polluting the environment. It was found that the hydrogen sulfide is at low concentrations important signaling molecule with a lot of physiological functions. Hydrogen sulfide is produced by enzymes CBS, CTH and 3-MPST in various tissues of the body, including the reproductive system.
We hypothesised that enzymes responsible for the endogenous production of hydrogen sulfide, CBS, CTH and 3-MPST, are present in porcine oocytes and their presence varies during meiotic maturation in cellular organelles. The goal of this study was to prove this hypothesis by cultivating porcine oocytes, detection of mitochondria, endoplasmic reticulum and hydrogen sulfide-releasing enzymes using imunocytochemistry and colocalization analysis.
Our results showed that enzymes releasing hydrogen sulfide, CBS, CTH and 3-MPST, are present in GV porcine oocytes and also in the oocytes matured to the MII stage, after 48 hours in vitro cultivation. We found that the distribution of these enzymes in cellular organelles in oocyte changed during meiotic maturation. There were significant changes in the distribution of enzymes 3-MPST and CBS in the mitochondria, levels of colocalization coefficients for enzyme 3-MPST increased, these coefficients for enzyme CBS decreased during meiotic maturation. In endoplasmic reticulum we found significant changes in the distribution of all three hydrogen sulfide-releasing enzymes. Levels of colocalitazion coefficients for CBS and 3-MPST increased, while levels of these coefficients for enzyme CTH decreased. Results of our experiments on porcine oocytes can help to clarify the role of gasotransmitter hydrogen sulfide during meiotic maturaion mammals of oocytes and are highly valueable because their possible application in breeding of farm animals and in human assisted reproduction.
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Factors affecting energy absorption of a plate during shock wave impact using a damage material modelCrosby, Zachary Kyle 07 August 2010 (has links)
This thesis examines the influences of five factors on the strain energy at failure of metallic alloy plates during a shock wave impact. The five factors are material type, initial damage, boundary conditions, plate thickness, and plate temperature. The finite element simulation matrix was developed using a statistical design of experiments (DOE) technique. The Eulerian hydrocode CTH was used to develop the pressure histories that were input into the finite element code Abaqus/Explicit, which implemented the Mississippi State University internal state variable (ISV) plasticity-damage model (DMG). The DMG model is based on the Bammann-Chiesa-Johnson (BCJ) ISV plasticity formulation with the addition of porosity and the void nucleation, growth, and coalescence rate equations that admit heterogeneous microstructures. Material type and thickness were the primary influences on the strain energy at failure, and the materials studied, magnesium and aluminum, showed two different failure mechanisms, tearing at the boundaries and spalling, respectively.
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Explicit Finite Element Comparison of the Lower Human Extremity under Blast LoadOyeka, Onyema 11 May 2013 (has links)
Most studies on blast explosion focus on a single technique or software. This Thesis directly compares several methods of simulating blast loads using LS-DYNA, ABAQUS and CTH software. The techniques appraised in this thesis include; Jones-Wilkins-Lee (JWL) equation of state (EOS), spherical incident wave formulation, and a direct planar blast load application. In the first section of this study, we analyzed a free air-blast generated by detonating 100 g of composition-4 (C-4). Next, we placed and examined the lower extremity model under the same blast parameters in different coupled and uncoupled scenarios. In the free air-blast study, all three codes gave similar results. The peak over pressure from ABAQUS was the closest in value to the experimentally measured data. In the second section, the JWL EOS method consistently produced higher-pressure response in the lower extremity elements compared to the other methods implemented.
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Évaluation de l'excrétion urinaire d'un biomarqueur pour la maladie de Fabry, le globotriaosylcéramide (Gb[indice inférieur 3]), chez des enfants normaux de la naissance à 6 moisBarr, Caroline January 2009 (has links)
La maladie de Fabry est une maladie héréditaire de surcharge, dont la transmission est liée au chromosome X qui résulte d'un déficit de l'[alpha]-galactosidase A. Le déficit enzymatique mène à une augmentation de glycosphingolipides, notamment le globotriaosylcéramide (Gb[indice inférieur 3]), dans les tissus et fluides biologiques. Le Gb[indice inférieur 3] est donc un biomarqueur ou indicateur de la présence de cette maladie chez les patients Fabry. Nous voulions évaluer la faisabilité de procéder à un projet pilote de recherche en vue d'un dépistage néonatal urinaire de la maladie de Fabry.La variation de l'excrétion du Gb[indice inférieur 3]/créatinine urinaire chez des enfants normaux dans la période néonatale jusqu'à l'âge de 6 mois est inconnue. Cette constatation nous a conduits au questionnement suivant : existe-t-il une variation dans la quantité du Gb[indice inférieur 3]/créatinine urinaire excrétée chez des enfants normaux de 0 à 6 mois de vie? Afin de répondre à cette question, nous avons procédé à une étude permettant de doser le Gb[indice inférieur 3]/créatinine chez des enfants normaux par spectrométrie de masse en tandem et ce, en comptant sur la collaboration des parents à effectuer un total de treize prélèvements d'urine pendant une période de 6 mois. Nous avons d'ailleurs évalué ladite collaboration des parents à nous faire parvenir les échantillons d'urine de leur bébé durant cette période. Nous avons utilisé une méthode par spectrométrie de masse en tandem avec des échantillons d'urine séchée sur papier filtre pour analyser simultanément le Gb[indice inférieur 3] total urinaire et la créatinine à différents temps soit 2, 3, 4, 6, 10, 14, 21, 28 jours, de même qu'à 2, 3, 4, 5 et 6 mois chez 37 filles et 39 garçons normaux. Le traitement quantitatif des données de la créatinine et du Gb[indice inférieur 3] urinaire a été fait par le logiciel QuanLynx (Waters). Nous avons divisé la variable du temps en quatre périodes pour les fins d'analyses statistiques : (1) < 6 jours; (2) 6-29 jours; (3) 30-90 jours; (4) > 90 jours. Nous avons procédé à des analyses statistiques comparatives du rapport Gb[indice inférieur 3]/créatinine de 728 échantillons pour les deux cohortes en fonction du temps. Une analyse de variance a été faite pour évaluer l'effet de l'âge et du sexe sur le rapport du logarithme du Gb[indice inférieur 3]/créatinine urinaire et l'effet de l'âge et du sexe sur la quantité d'excrétion de la créatinine urinaire seulement. Nous avons observé un effet significatif de l'âge sur la créatinine (p < 0.0001). En ce qui concerne les résultats du rapport du Gb[indice inférieur 3]/créatinine, il y a une augmentation non significative de la médiane dans les périodes 1 et 2 pour les garçons (Période 1: Médiane 53.9; Min-Max 0 - 369.3 [micro]g/mmol créatinine; Période 2: Médiane 92.5; Min-Max 0 - 611.1 [micro]g/mmol créatinine ; p = 1.0000). Chez les filles, l'excrétion du Gb[indice inférieur 3]/créatinine est plus élevé à la naissance et présente une tendance à l'accroissement entre les périodes 1 et 2 (Période 1: Médiane 59.5; Min-Max 0 - 669.9 [micro]g/mmol créatinine; Période 2: Médiane 96.1; Min-Max 0 - 456.1 [micro]g/mmol créatinine ; p = 1.0000). Par ailleurs, l'excrétion du Gb[indice inférieur 3]/créatinine chez les garçons diminue de façon significative entre les périodes 2 et 4 (Période 2: Médiane 92.5; Min-Max 0 - 611.1 [micro]g/mmol créatinine; Période 4: Médiane 14.6; Min-Max 0 - 158.5 [micro]g/mmol créatinine ; p < 0.0001); au niveau des filles, il y a une diminution non significative de la médiane de la période 2 à la période 3 (Période 2 : Médiane 96.1; Min-Max 0 - 456.1 [micro]g/mmol créatinine ; Période 3 : Médiane 35.6; Min-Max 0 - 254.4 [micro]g/mmol créatinine p = 0.2290) et une légère augmentation à la période 4 (Période 4 : Médiane 42.7; Min-Max 0 - 617.2 [micro]g/mmol créatinine). Ainsi, nous pouvons constater qu'il existe une grande variabilité de l'excrétion du Gb[indice inférieur 3]
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Rewarding inventive ingenuity through patent ownership as part of the Australian innovation strategyEliades, Dimitrios George January 2007 (has links)
The government has indicated that innovation fosters economic growth and is essential to maintaining a competitive position in international markets. Patents are the preferred mechanism by which the Australian Government and other governments encourage their nationals to protect their innovations. The question of the entitlement was raised in several cases in the Federal Court of Australia where there has been a failure to name all of the inventors on a patent grant (non-joinder) or where persons were mis-named as inventors, who were not and consequently have no interest in a grant (rnis-joinder). In both cases, parties who were not themselves daiming an entitlement to the invention, brought objections based on a number of grounds, including entitlement. The results have been the revocation of the patent in the case on the non-joinder of an inventor and in the case of mis-joinder, the preliminary view of a judge of the Federal Court has been, that the patent would be invalid through lack of entitlement. The result is that competitors are permitted to 'exploit' the invention, as the subject matter is not protected by a patent. The implications are far reaching, For example, where a research team in collaboration with another develops an invention but omits the inventive contribution of even one member of one team or includes a person who has not made an inventive contribution in the patent grant, the patent will be invalid. In these circumstances, the author considers that the result produces a disincentive to innovate. Consideration of this area in other jurisdictions reveals that the U.S. and the U.K. have recognised this as an unsatisfactory state of affairs. As a result, Congress in the U.S. made provision in their Patent Code in the early 1950's, that in the case of error or mistake giving rise to a non-joinder or mis-joinder of inventors, the patent would not be invalid but could be rectified by the Director of Patents and Trade Marks (the 'Director'). In the U.K., the Comptroller has powers to deal with a wide variety of cases involving entitlement to ownership of a patent. The situations include but are not limited to cases where some but not all of the persons entitled to the grant have been granted the patent, i.e. non-joinder, or where a person entitled to be granted a patent, has been granted a patent together with a person who is not entitled, i.e. mis-joinder. The thesis will focus on the non-joinder and mis-joinder of inventors, but the U.K. provision addresses a wider field of parties entitled, whether entitled as inventors or on some other basis. In addition, the U.K. and Germany have made provision restricting the persons who are able to challenge a patent on entitlement grounds. This is restricted to those persons having an interest in the patent, rather than open to any person, as is the case in Australia. The Australian decisions have been determined on historic cases dating back to the 17th century. It is timely to consider amendments which will overcome revocation of patents under Australian law, for what is essentially a matter between the persons interested. These amendments will accordingly encourage innovation, particularly in an environment where intellectual property has taken on greater importance and where the identification of the inventor has become more complex as collaborations in research become more common.
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Voluntary environmental reporting: the why, what and howDe Silva, T-A. January 2008 (has links)
Society is increasingly calling for organisations to demonstrate corporate social responsibility (CSR). To fulfil this demand, organisations need to be accountable, democratic and transparent to their stakeholders. This can be achieved using a number of tools including communication about the environmental, social and economic impacts of an organisation’s actions and activities. Yet despite the importance of communicating environmental information, and society’s heightened environmental awareness, organisations are still demonstrating an insufficient commitment to environmental reporting, continuing their reluctance to be open and accountable about their environmental impacts. This suggests organisations currently have little understanding of why they should report, what they should report and/or how they should report. For environmental reporting progress to be achieved it is important that we have knowledge of how various factors influence voluntary environmental reporting engagement. This research, in contributing to and extending the body of environmental reporting knowledge, aims to provide an understanding of the Why, What and How of voluntary environmental reporting by specifically examining: why organisations should, and why organisations do, voluntarily report environmental information; what environmental information organisations should, and what environmental information organisations do, voluntarily report; and how organisations should, and how organisations do, voluntarily report environmental information. In using a combination of research methodologies this research extends prior CSR reporting studies – closing the gap between voluntary environmental reporting practice and theory, providing better insights into the underlying reasons and motivations for voluntary environmental reporting, and providing improved knowledge of the considerations made by companies as part of the voluntary environmental reporting process. In doing so, this research presents a more recent examination of voluntary environmental reporting in the annual reports of New Zealand and Australian publicly listed companies. Aspects of voluntary environmental reporting that have not been extensively examined before, particularly in Australasia, are examined. These include a focus on content-quality (as opposed to reporting quantity), an investigation of the effect of public pressure (using a combination of three proxy measures), and, through the use of qualitative research, an expansion of the insights obtained from quantitative data. This research finds that New Zealand and Australian publicly listed companies continue to have an insufficient and incorrect understanding of why they should report, what they should report and/or how they should voluntarily report environmental information. This deficient understanding results in voluntary environmental reporting in their annual reports which is inadequate – the reporting lacks meaning and purpose (i.e. has form but little or no substance), and reflects managers’ incorrect perceptions about the environmental impact of their company’s actions and activities. As a result voluntary environmental reporting in the annual reports of New Zealand and Australian publicly listed companies fails to “… give an understanding, which is not misleading, …” of the environmental consequences of an organisation’s actions and activities (adapted from Alexander & Jermakowicz, 2006, p. 132), providing little accountability to stakeholders, and serving neither external stakeholders nor those reporting well. As the demand for organisations to demonstrate accountability to stakeholders continues to increase over time it is important to develop informed environmental reporting guidance and undertake further examinations of the Why, What and How of environmental reporting.
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Impact-initiated combustion of aluminumBreidenich, Jennifer L. 07 January 2016 (has links)
This work focuses on understanding the impact-initiated combustion of aluminum powder compacts. Aluminum is typically one of the components of intermetallic-forming structural energetic materials (SEMs), which have the desirable combination of rapid release of thermal energy and high yield strength.
Aluminum powders of various sizes and different levels of mechanical pre-activation are investigated to determine their reactivity under uniaxial stress rod-on-anvil impact conditions, using a 7.62 mm gas gun. The compacts reveal light emission due to combustion upon impact at velocities greater than 170 m/s. Particle size and mechanical pre-activation influence the initiation of aluminum combustion reaction through particle-level processes such as localized friction, strain, and heating, as well as continuum-scale effects controlling the amount of energy required for compaction and deformation of the powder compact during uniaxial stress loading. Compacts composed of larger diameter aluminum particles (~70µm) are more sensitive to impact initiated combustion than those composed of smaller diameter particles. Additionally, mechanical pre-activation by high energy ball milling (HEBM) increases the propensity for reaction initiation.
Direct imaging using high-speed framing and IR cameras reveals light emission and temperature rise during the compaction and deformation processes. Correlations of these images to meso-scale CTH simulations reveal that initiation of combustion reactions in aluminum powder compacts is closely tied to mesoscale processes, such as particle-particle interactions, pore collapse, and particle-level deformation. These particle level processes cannot be measured directly because traditional pressure and velocity sensors provide spatially averaged responses. In order to address this issue, quantum dots (QDs) are investigated as possible meso-scale pressure sensors for probing the shock response of heterogeneous materials directly. Impact experiments were conducted on a QD-polymer film using a laser driven flyer setup at the University of Illinois Urbana-Champaign (UIUC). Time-resolved spectroscopy was used to monitor the energy shift and intensity loss as a function of pressure over nanosecond time scales. Shock compression of a QD-PVA film results in an upward shift in energy (or a blueshift in the emission spectra) and a decrease in emission intensity. The magnitude of the shift in energy and the drop in intensity are a function of the shock pressure and can be used to track the particle scale differences in the shock pressure. The encouraging results illustrate the possible use of quantum dots as mesoscale diagnostics to probe the mechanisms involved in the impact initiation of combustion or intermetallic reactions.
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