Nonlinear prize money structures are used in professional golf tournaments in order to induce competitors to exert a maximum level of effort. While there has been a growing amount of literature using professional golf data to test tournament theory’s basic prediction that increasing prize levels results in an increase in player effort level, no consistent narrative has emerged. Furthermore, in 2007, the PGA Tour introduced the FedExCup system, which significantly altered the ranking and prize money structure of professional golf. This paper incorporates data from the 2011 PGA tour season to analyze whether or not the introduction of the FedExCup has led to increased effort level on the part of competitors, as predicted by tournament theory. The results negate the predictions of tournament theory and suggest that an increase in tournament prize money is associated with a corresponding increase in player scores over the course of the tournament. However, these findings can be explained by examining the dramatic increase in PGA Tour prize money levels over the last two and a half decades, which has induced golfers to decrease their average level of effort.

The productivity of individuals can be altered by cognitive environmental factors such as those that induce psychological pressure. The goal of this analysis is to determine the extent to which a selection of variables influences an individual’s perception of pressure and its subsequent effect on productivity. To do so, the performance of golfers under pressure on the PGA TOUR was proxied using the scrambling percentage statistic. Two regressions, one using data from players who were cut at the end of the second round and the other using data from players who were not cut at the end of the second round, were used to study how golfers’ scrambling percentage for a given round was influenced by changes in experience, time, rank, tournament prestige, and their expected future performance. An increase in variables representing tournament prestige, tournament round number, and player position on the leader board lead to an increase in pressure which in turn leads to poorer subsequent performance. On the other hand, an increase in player experience and the knowledge that a player would be cut at the end of the second round tend to decrease pressure and increase player performance.

Poly-γ-glutamic acid (γ-PGA) is a naturally occurring biopolymer made up of repeating units of glutamic acid and can be potentially used for multiple applications. This study compared the production of γ-PGA by eight bacteria (B. subtilis 23856, B. subtilis 23857, B. subtilis 23858 B. subtilis 23859, B. subtilis natto, B. licheniformis 1525, B. licheniformis 6816 and B. licheniformis 9945a) in GS and E media. B. subtilis natto and B. licheniformis 9945a have been investigated extensively for γ-PGA production, however, the remaining six have not previously been used. Using the eight bacteria, yields of up to 22.3 g/l were achieved in shake flasks. On characterization, it was observed that γ-PGA with different properties (crystallinity, acid/salt form and molecular weights ranging from 3,000 Da to 871,000 Da) was produced. Production of γ-PGA by B. subtilis natto in GS medium was scaled up using a fermenter and was tested for novel probiotic applications. The survival of probiotics during freeze drying, storage and ingestion was improved by combining them with a γ-PGA matrix. For L. paracasei, 10% γ-PGA protected the cells significantly better (P < 0.05) than 10% sucrose during freeze drying, whereas for B. longum and B. breve, it showed comparable cryoprotectant activity (P > 0.05) to 10% sucrose. This study also demonstrated the potential use of a non-dairy foodstuff (orange juice) for delivery of probiotics. Two Bifidobacteria strains protected with γ-PGA survived significantly better (P < 0.05) in orange juice for 39 days, with a log reduction in viability of less than 2.99 CFU/ml, when compared to unprotected cells, which showed complete loss in viability by day 20. In addition, γ-PGA protection improved survival of Bifidobacteria in a solution mimicking the environment of the stomach. γ-PGA-protected Bifidobacteria showed little (< 0.47 log CFU/ml) or no loss in viability when stored in simulated gastric juice (pH 2.0) for four hours, whereas unprotected cells died within two hours.

Due to rapid growth of home entertainment consumer market, video technology has been continuously pushed to deliver sharper pictures with higher resolution. This has brought about stringent requirements on the video analog front end, which often coupled with the low power and low voltage regulations had to deal with short channel effects of the deep submicron CMOS processes. This thesis presents the design of a fully differential programmable gain amplifier, as a subcircuit of a larger video digitizing IC designed at division of Electronic Systems. The switched capacitor architecture of the PGA does not only buffer the signal, but performs compensation for the sync-tip of analog video signal. The pseudo differential OTA eliminates tail current source and maintains high signal swing and has efficient common mode feedforward mechanism. When coupled with a similar stage provides inherent common moode feedback without using an additional SC-CMFB block. The PGA has been implemented using a 65 nm digital CMOS process. Expected difficulties in a 1.2 V OTA design make themselves evident in 65 nm, which is why cascaded OTA structures were inevitable for attaining gain specification of 60 dB. Nested Miller compensation with a pole shifting source follower, stabilizes the multipole system. The final circuit attains up to 200 MHz bandwidth and maintains high output swing of 0.85 V. High slew rate and good common mode and power supply rejection are observed. Noise requirements require careful design of input differential stage. Although output source follower stabilized the system, it reduces significant bandwidth and adds to second order non-linearity.

It is proposed to continue operating the graphite moderated Advanced Gas-cooled Reactor (AGR) fleet past its design life. Nuclear graphite's properties change in reactor and our limited mechanistic understanding of the relationship between graphite structure, across different lengthscales, and its properties limits our ability to predict its future behaviour. An improved understanding of the relationship between graphite's structural features, the relationship between features across different lengthscales and their effect on material properties would all contribute to a mechanistic understanding of graphite behaviour. Thermal expansion generates thermal strains and stresses in the graphite core during thermal transients, such as during reactor start-up and shut-down. Thermal expansion is a function of graphite crystal thermal expansion, crystallographic preferred orientation and microstructure, although the exact relationship between these is not understood. It is also altered by neutron irradiation. This thesis investigates graphite microstructure, virgin and irradiated, and its crystallographic preferred orientation, specifically as they pertain to thermal expansion. The microstructure of British nuclear graphites PGA and Gilsocarbon, used in the Magnox and AGR fleet respectively, have been investigated using scanning electron microscopy (SEM). Trepanned AGR graphite, that is, graphite drilled from the reactor brick during routine inspection is examined. These samples are from the 2012 Hinkley Point B inspection campaign and are taken from several points through the brick thickness. This provides a 'snap shot' of current AGR graphite condition. Deep trepan samples removed from further into the brick thickness are observed for the first time. Neutron damage was observed in Magnox graphite, irradiated in an inert environment in the material test reactor programme INEEL. The spatial variation in texture of PGA and Gilsocarbon, and the change in such texture after prestress was observed using synchrotron x-ray diffraction. Numerical models were used to identify the required texture change to produce changes in CTE, observed by other authors, during in-situ stress. PGA filler lamellae are arranged in parallel arrays and Gilsocarbon's smaller platelets are arranged in bunched clusters. Severe radiolytic oxidation is observed at all trepan locations, with oxidation decreasing away from the fuel. Radiolytic oxidation occurs at platelet edges. Texture measurements have indicated that PGA graphite exhibits significant spatial variation in texture. Gilsocarbon exhibits less variation but the variation observed is large enough to cause increased thermal stresses. Texture measurements of prestressed graphite have indicated that texture changes also vary spatially. Texture results and SEM observations indicate that spatial variation in texture is caused by spatial variation in microstructure. Changes to the filler particle during prestress may alter local texture. These results indicate there is a link between nuclear graphite's microstructure and its texture. The texture, a function of lamellae or platelet arrangement, determines its thermal expansion. Spatial variations in microstructure formed during manufacturing leads to spatial variations in CTE and possibly other texture sensitive properties, such as dimensional change. Deformation of the lamellae or platelets during stress; thermal creep or irradiation creep is expected to contribute to the observed change in properties associated with these stimuli.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22759号 / 工博第4758号 / 新制||工||1744(附属図書館) / 京都大学大学院工学研究科都市社会工学専攻 / (主査)教授 三村 衛, 教授 渦岡 良介, 准教授 肥後 陽介 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

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Tesis por compendio / [ES] La rehabilitación de las redes de drenaje es uno de los procesos fundamentales que los administradores y responsables de la gestión de redes de drenaje deben implementar para adaptar las redes defectuosas a los efectos adversos del cambio climático y la urbanización. Las soluciones tradicionales pasan por la sustitución de tuberías o la instalación de tanques de tormenta (TT). En esta tesis, el escenario propuesto combina la sustitución de tuberías y la instalación de TT para la rehabilitación de redes de drenaje. Los resultados de varias simulaciones en varias redes mostraron que el uso combinado de la sustitución de tuberías y la instalación de TT en la rehabilitación de redes de drenaje proporciona mejores resultados que la separación de los dos escenarios de rehabilitación. Tal metodología de rehabilitación necesita un tiempo de computación elevado para proporcionar soluciones aceptables que a menudo se encuentran atrapados en mínimos locales. El objetivo de esta tesis es proponer una metodología que permita obtener mejores resultados durante la rehabilitación de redes de drenaje considerando el uso combinado de la sustitución de tuberías y la instalación de TT. La metodología debe considerar la reducción del espacio de búsqueda (SSR). Cuatro opciones claves están combinadas para lograr reducir el espacio de búsqueda del problema. Estas opciones son: Reducir la cantidad de nudos en los que podrían instalarse los TT. Reducir el número de líneas en las que podría haber un cambio en el diámetro Reducir la discretización que se hace de la sección de cada uno de los TT. Reducir el número de diámetros candidatos en las tuberías. Una vez que se reduce el espacio de búsqueda, el algoritmo pseudo genético (APG) utilizado en esta tesis para la optimización mono-objetivo puede explorar más partes del espacio de búsqueda en menos tiempo. Lo que resulta es la obtención de mejores resultados. Por la optimización multiobjetivo, el NSGA-II utilizado puede proporcionar frentes de Pareto rápidamente para los diferentes escenarios considerados después del proceso de optimización. El objetivo general se dividió en objetivos específicos que se detallan a continuación: El primer objetivo específico consiste en formular un problema de optimización que verifique que la rehabilitación teniendo en cuenta la instalación de los TT y la sustitución de las tuberías proporciona mejores resultados que cualquiera de las dos estrategias implementadas por separado. Evaluar adecuadamente las funciones de costes utilizadas para formar las funciones objetivo constituye el segundo objetivo específico. Los diferentes costes considerados son: costes de sustitución de tuberías, costes de instalación de TT y costes de daños por inundación. El tercer objetivo específico es desarrollar un modelo de rehabilitación considerando la instalación de TT y la sustitución de tuberías, basado en APG y el Modelo SWMM. Los costes de inversiones y los costes de daños por inundaciones no se pueden sumar debido a sus tipos. Los costes de inversiones son reales mientras que los costes de daños por inundaciones son futuribles, dependen de la probabilidad de ocurrencia de la lluvia. Por lo tanto, el cuarto objetivo específico de esta tesis es proponer un algoritmo multiobjetivo evolucionario para la rehabilitación de redes de drenaje considerando la instalación de TT y la sustitución de tuberías. Para la optimización de un mono objetivo y multiobjetivo, el tiempo de cálculo es elevado. También las soluciones objetivas estaban atrapadas en mínimos locales. El quinto objetivo es proponer una metodología de reducción del espacio de búsqueda (SSR) para resolver este problema. El sexto objetivo específico consiste en llevar a cabo un análisis de sensibilidad para verificar los efectos del SSR en el resultado final del proceso de optimización. Por lo tanto, se seleccionaron diferentes tamaños de poblac / [CA] La rehabilitació de les xarxes de drenatge és un dels gestors de processos fonamentals i la necessitat responsable d'implementar per adaptar les xarxes defectuoses als efectes adversos del canvi climàtic i la urbanització. A la literatura, la installació de canonades o substitució de canonades són els dos escenaris presentats pels autors. En aquesta tesi, un tercer escenari proposa combinar la installació de canonades de substitució i tancs de tempesta (TT) per a la rehabilitació de xarxes de drenatge. Els resultats de diverses simulacions a diverses xarxes van mostrar que la combinació d'ús de canvis de substitució de canonades i TT a la rehabilitació de xarxes de drenatge proporciona millors resultats que la separació dels dos escenaris de rehabilitació. Desafortunadament, aquesta metodologia de rehabilitació requereix temps de càlcul elevat per proporcionar solucions acceptables que sovint es troben en mínim local. L'objectiu d'aquesta tesi és proposar una metodologia que permeti reduir el temps de càlcul i obtenir millors resultats durant la rehabilitació de la xarxa de drenatge considerant l'ús combinat de la instal·lació dels TT de substitució de canonades. L'estratègia adoptada combina, en una metodologia estructurada, quatre opcions clau per reduir l'espai de cerca del problema: Reduir el nombre de nodes en què podrien instal·lar-se els TT. Reduir el nombre de línies en què podria haver-hi un canvi de diàmetre Reduir la discretització que es fa de la secció de cadascun dels TT. Reduir la quantitat de diàmetres candidats à les canonades. Un cop reduït l'espai de cerca, l'algorisme pseudo-genètic (PGA) que s'utilitza en aquesta tesi per a l'optimització d'un únic objectiu (SO) pot explorar fàcilment l'espai de cerca en menys temps, resultant en obtenir millors resultats. Per a l'optimització del MO, la NSGA-II pot proporcionar fronts de Pareto ràpidament per als diferents escenaris considerats després del procés d'optimització. L'objectiu general es va a dividir en objectius específics detallats a continuació: El primer objectiu específic consisteix a formular un problema d'optimització que verifiqui que la rehabilitació considerant la instal·lació de TT i la seva substitució proporciona millors resultats que qualsevol de les dues estratègies implementades per separat. Valorar adequadament les funcions de cost que s'utilitzen per formar les funcions objectives, i constitueix el segon objectiu específic. Els diferents costes considerats són: Costes d'inversions i costes de danys a les inundacions. El tercer objectiu específic és desenvolupar un model de rehabilitació considerant la instal·lació de TT i la substitució de canonades, basant-se en el PGA i el model SWMM. Els costos d'inversions i els costos de danys per inundacions no es poden sumar a causa d'un tipus. Els costes d'inversions són reals mentre els costes d'anuncis per a les futures fonts del futur són dependents de la probabilitat d'obertura de la pluja. Per tant, el cos objectiu específic d'aquesta tesi és propiciar un algorisme multiobjetiu evolutiu per a la rehabilitació de la xarxa de navegació considerant la instal·lació de TT i la substitució de tuberies. Per a l'optimització d'un únic objectiu i multi-objectiu, el temps de càlcul s'eleva. També es va sospitar que les solucions objectives eren atrapades en els mínims locals. El cinquè objectiu és proposar una metodologia de la reducció de l'espai de cerca (SSR) per resoldre aquest problema El sisè objectiu específic consisteix a realitzar una anàlisi de sensibilitat per verificar els efectes de SSR sobre el resultat final del procés d'optimització. Per tant, es van seleccionar diferents grandàries de població i valors de criteris de parada i es van realitzar simulacions per a diferents configuracions. El setè objectiu específic d'aquesta tesi és proposar una nova metodologia de rehabilitació considerant la tècnica / [EN] Drainage networks rehabilitation is one of the fundamental process that managers and responsible need to implement to adapt defective networks to climate change and urbanization adverse effects. In the literature, pipes substitution or storm tanks (STs) installation are the two scenarios presented by authors. In this thesis, a third scenario proposed combine pipes substitution and STs installation for drainage networks rehabilitation. Results of several simulations on various networks showed that the combine use of pipes substitution and STs installation in drainage networks rehabilitation provides better results than separation of the two rehabilitation scenarios. Unfortunately, such rehabilitation methodologies are computationally time consumers. They need much time to provide acceptable solutions which are often caught up in local minima. The aim of this thesis is to propose a drainage networks rehabilitation methodology based on the combine use of pipes substitution and STs installation. The methodology considers search space reduction (SSR) technique. The adopted strategy combines in a structured methodology four key options aiming at reducing the search space (SS) of the problem: Reduce the number of nodes in which STs could potentially be installed. Reduce the number of lines in which there could potentially be a change in diameter Reduce the discretization that is made of the section of each of the STs. Reduce the number of candidate diameters in the pipes. Once the search space is reduced, the pseudo genetic algorithm (PGA) used in this thesis for single objective (SO) optimization can easily explore the search space in less time resulting in the obtention of better results. For the MO optimization, the NSGA-II can provide rapidly Pareto fronts for the different considered scenarios after the optimization process. The general objective was divided in specific objectives detailed as follow: The first specific objective consists of formulate an optimization problem that verifies that rehabilitation considering STs installation and pipes substitution provides better results than any of the two strategies implemented separately. Adequately assess the cost functions used to form the objective functions constitutes the second specific objective. The different costs considered are: Investments costs and flood damage costs. The third specific objective is to develop a rehabilitation model considering STs installation and pipes substitution, based on PGA and the Storm Water management Model. Investment costs and flood damage costs could not be summed due to their types. Investment costs are reals while, flood damage costs depend on the rainfall probability. So, the fourth specific objective of this thesis is to propose a MOEA for drainage networks rehabilitation considering STs installation and pipes substitution. For SO and Multi-objective (MO) optimization, the computation time is elevated. It was also suspected that the objective solutions were caught up in local minima. The fifth objective is to propose an SSR methodology to solve this issue The sixth specific objective consist of carry out a sensitivity analysis to verify the effects of the SSR on the final result of the optimization process. So, different population sizes and stop criteria values were selected and simulation for different configurations were performed. The seventh specific objective of this thesis is to propose a new rehabilitation methodology considering SSR technique for MO optimization. For each specific objective presented in this thesis, an application to a drainage network has been made and the obtained results were satisfactory. A simple network was used to apply the simple optimization methodology based on PGA algorithm A medium size network was used to apply the SO optimization, the MO optimization and the SSR methodology. Finally, a large and mesh network was used to apply the MO optimization methodology considering SSR. / Ngamalieu Nengoue, UA. (2019). URBAN DRAINAGE NETWORK REHABILITATION CONSIDERING STORM TANK INSTALLATION AND PIPE SUBSTITUTION [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/129869 / Compendio

Made available in DSpace on 2016-06-02T19:56:40Z (GMT). No. of bitstreams: 1 3187.pdf: 3659896 bytes, checksum: 975ac91a3eb67a4347c326de8f22bf8e (MD5) Previous issue date: 2010-03-31 / Universidade Federal de Minas Gerais / This master's thesis project aims at studying the dynamic optimization of the operation of a bench scale (up to 5L) automated, agitated and aerated bioreactor, where the semi-continuous cultivation of recombinant Pichia pastoris is run. This yeast was cloned using the PGK1 promoter, which precludes the use of methanol as inducer, expressing constitutively the enzyme penicillin G Acylase (PGA) from Bacillus megaterium. While the group of molecular biology of DEQUFSCar is working on cloning the PGA, d P. pastoris expressing the enzyme &#61665;- amylase from Bacillus subtilis was cultivated. This clone, provided by prof. Fernando Torres, UnB, uses the same construction and, therefore, its kinetics of growth and production should be very similar to the PGA s. Cultivation of recombinant Pichia pastoris was performed in flasks (skaker) using standard culture medium, aiming at obtaining kinetic data, which are the starting point for the escalation to a benchtop bioreactor. Following that, tests were performed in a 5L bioreactor in batch and fed batch operation modes. With the bioreactor data , kinetic parameters of growth, to be further used in the simulations, were estimated, using a hybrid algorithm (which combines the global method Simulated Annealing, with the local one Levenberg- Marquardt). This algorithm, is implemented in Matlab and available in the software library of Ladabio (Laboratory of Development and Automation of Bioprocesses ). From these data, models of microbial growth and of production were developed, following a classic approach (unstructured, non-segregated). Computer simulations using different feeding strategies and employing these models allowed mapping the dynamics of the system. From this information, optimal control strategies were proposed to define optimal feeding profiles. Cellular concentrations of 5.4 g/L (dry weight) were reached in shaker (20h of cultivation, when glucose is exhausted), expressing 218 U/mL of &#61665;-amylase, compared to 11.4 g/L (dry weight) that were achieved in cultures in a bioreactor in batch simple (10h of cultivation, when glucose is exhausted), expressing 156 U/mL of &#61665;-amylase In fed-batch cultures, cell concentrations of up to 45 g/L were achieved, expressing up to 260 U/mL of &#61665;- amylase, with a productivity of 5.2 U/mL/ h. In fed-batch cultures of P. pastoris expressing PGA, cell concentrations of up to 35 g/L were achieved. Enzyme activity was not detected in the culture broth due to the effect of glycosylation. Immunodetection reaction confirmed the expression of the recombinant enzyme. Four specific growth rate equations were adjusted, with different types of inhibition by one product, detected at significant levels by liquid chromatography highperformance, but not yet identified. This metabolite was added as an inhibitor in kinetic models, using the peak areas, normalized as a pseudoconcentration. The best fit to the experimental data were the Monod kinetic model with non-competitive inhibition. Typical values obtained for the maximum specific growth and glucose/ cell conversion factor in bioreactor were &#61676;max=0,24 h-1 and YX/S = 0,48. Algorithm for optimal control in open loop was developed and successfully implemented, providing a robust profiles of great power, whose validation is proposed as a continuation of this work. / Este mestrado se propoe a estudar a otimizacao dinamica de biorreator automatizado, tipo tanque agitado e aerado, em escala de bancada (ate 5L), onde se processa o cultivo semi-continuo de Pichia pastoris recombinante. Essa levedura foi clonada pelo grupo do prof. Fernando Torres, da UnB, utilizando o promotor PGK1, que dispensa a utilizacao de metanol como indutor, expressando constitutivamente a enzima &#61665;-amilase de Bacillus subtilis. Durante a execucao deste mestrado, a enzima penicilina G acilase (PGA) de Bacillus megaterium esta sendo clonada pelo grupo de biologia molecular do DEQ-UFSCar usando a mesma construcao e, portanto, a cinetica de crescimento e producao da PGA heterologa devera ser muito semelhante as da &#61665;-amilase, utilizada como estudo de caso para otimizacao do bioprocesso. Cultivos de Pichia pastoris recombinante foram realizados em frascos agitados, utilizando meio de cultivo padrao, objetivando o levantamento de dados cineticos, ponto de partida para o escalonamento em biorreator de bancada. Posteriormente, foram realizados ensaios em biorreator de 5L, em batelada e batelada alimentada. Com os dados obtidos nos cultivos em biorreator, e utilizando algoritmo hibrido para estimativa de parametros (que combina o metodo global Simulated Annealing, com o local de Levenberg-Marquardt), implementado em MatLab e disponivel no LaDABio (Laboratorio de Desenvolvimento e Automacao de Bioprocessos), foram ajustados parametros cineticos de crescimento, para serem utilizados nas simulacoes dos cultivos em biorreator. A partir dai, foi desenvolvido modelo de crescimento microbiano e de producao, utilizando um enfoque classico (modelo nao-estruturado, nao-segregado) para descrever o sistema. Com isso, torna-se possivel realizar simulacoes em computador usando diferentes estrategias de alimentacao, para mapear a dinamica do sistema. A seguir, foram desenvolvidos algoritmos de controle otimo em malha aberta para definicao de estrategias de alimentacao. Concentracoes celulares de 5,4 g/L (massa seca) foram alcancadas em cultivos em camara rotatoria (20h de cultivo, quando se esgota a glicose), expressando 218 U/mL de &#61665;-amilase, comparado com 11,4 g/L(massa seca) que foram atingidos em cultivos em biorreator em bateladas simples (10h de cultivo, quando se esgota a glicose), expressando 156 U/mL de &#61665;-amilase. Em cultivos em batelada alimentada concentracoes celulares de ate 45 g/L foram atingidas, expressando ate 260 U/mL de &#61665;-amilase, com uma produtividade de 5,2 U/mL/h. Em cultivo em batelada alimentada de P. pastoris expressando PGA, concentracoes celulares de ate 35 g/L foram atingidas. Nao foi detectada atividade enzimatica no caldo de cultivo devido ao efeito da glicosilacao. Reacao de imunodeteccao confirmou a expressao da enzima recombinante. Foram ajustadas quatro equacoes de velocidade especifica de crescimento, com diferentes tipos de inibicao por um produto, detectado em niveis importantes por cromatografia liquida de alto desempenho, mas ainda nao identificado. Esse metabolito foi inserido como inibidor nos modelos cineticos, utilizando as areas dos picos, normalizadas, como uma pseudoconcentracao. Os melhores ajustes aos dados experimentais foram com modelo cinetico de Monod com inibicao nao-competitiva. Valores tipicos obtidos para a velocidade especifica maxima de crescimento e de fator de conversao glicose/celula em biorreator foram &#61676;max = 0,24 h-1 e YX/S = 0,48. Algoritmo de controle otimo em malha aberta foi desenvolvido e implementado com sucesso, prevendo de forma robusta perfis otimos de alimentacao, cuja validacao fica proposta como continuidade deste trabalho.

The conception of electrospinning can trace its roots back more than 400 years, when it was observed that rubbed amber can deform a droplet of water on a smooth surface, and is based upon simple concepts of charge separation and surface tension. Since that time, considerable effort has been directed at both the cause and utility of this phenomenon. The specific aim of this dissertation project was to develop an automated electrostatic processing apparatus that was capable of controlling the three-dimensional architecture of an electrospun scaffold to further improve its utility in tissue engineering. The efficacy of using this technique has been well documented and can be adapted to produce tissue engineering scaffolds for a variety of tissues and organs. This apparatus incorporates precise mandrel motion. The system is capable of 0 - 5000 revolution per minute rotation, 0 - 25 inch per second translation and ± 40° rotation about the electrospinning jet axis for repeatable scaffold production. Fiber alignment and scaffold density are precisely controlled by rotating a mandrel along one axis, translation along that same axis, and rotation around the second axis perpendicular to the electrospun fiber stream. The control is accomplished with a PC based "supervisory" control program written partially in the LabVIEW® programming language and partially in SI Programmer supplied by Applied Motion Products. Scaffold thickness and fiber diameters are determined by the syringe metering pump flow rate, material being electrospun and solution concentrations. Through extensive laboratory analysis (mechanical testing and both optical and electron microscopy), parameters such as fiber orientation, diameter and mechanics can be predictive from specific polymer setups. Our laboratory has demonstrated the ability to electrospin natural and synthetic polymers and this apparatus will be utilized to tailor scaffolds to meet specific tissue engineering needs by creating a truly biomimicking scaffold / extracellular matrix.