In the field of regenerative medicine, there is a need to develop technologies that can increase the overall efficiency of imaging and expanding cells in culture and in complex heterogeneous arrangements necessary for tissue construction. Long-term live cell imaging has the potential to significantly enhance our understanding of intercellular signaling pathways and the dependence of phenotype on cell arrangement. A transdisciplinary approach has been taken to bridge the fields of cell biology, robotics, and photonics to create a long-term live cell imaging system capable of single cell handling as well as the acquisition of multiple types of data needed for data mining and a general informatics approach to cell culture. A Bio-Assembly Mosaic Builder and Informatics (BAMBI) system was designed and developed using custom software to control a 3-axis stage manufactured by Galil Inc, and custom 1-axis micromanipulator for robotic operations. The software also employs a Sony charged-coupled device sensor for real-time image feedback and data acquisition. The system is mounted on a Carl Zeiss Axiovert 200 inverted microscope. Custom-built environmental controls are used to maintain the temperature, humidity, and gas conditions for extended live cell work. The software was designed using Visual C++ for the Windows PC platform using an object orientated and modular design methodology to allow the BAMBI software to continue to grow with new tasks and demands as needed. The modular approach keeps functional groups of code within context boundaries allowing for easy removal, addition, or changes of functions without compromising the usability of the whole system. BAMBI has been used to image cells within a novel cell culture chamber that constricts cell growth to a true monolayer for high-resolution imaging. In one specific application, BAMBI was also used to characterize and track the development of individual Colony Forming Units (CFU) over the five-day culture period in 5-day CFU-Hill colony assays. The integrated system successfully enabled the tracking and identification of cell types responsible for the formation of the CFU-Hill colonies (a putative endothelial stem cell). BAMBI has been used to isolate single hematopoietic stem cell (HSC) candidate cells, accumulate long-term live cell images, and then return these cells back to the in-vivo environment for further characterization. From these results, further data mining and lineage informatics suggested a novel way to isolate and purify HSCs. Studies such as these are the fundamental next step in developing new therapies for regenerative medicine in the future.

In the field of regenerative medicine, there is a need to develop technologies that can increase the overall efficiency of imaging and expanding cells in culture and in complex heterogeneous arrangements necessary for tissue construction. Long-term live cell imaging has the potential to significantly enhance our understanding of intercellular signaling pathways and the dependence of phenotype on cell arrangement. A transdisciplinary approach has been taken to bridge the fields of cell biology, robotics, and photonics to create a long-term live cell imaging system capable of single cell handling as well as the acquisition of multiple types of data needed for data mining and a general informatics approach to cell culture. A Bio-Assembly Mosaic Builder and Informatics (BAMBI) system was designed and developed using custom software to control a 3-axis stage manufactured by Galil Inc, and custom 1-axis micromanipulator for robotic operations. The software also employs a Sony charged-coupled device sensor for real-time image feedback and data acquisition. The system is mounted on a Carl Zeiss Axiovert 200 inverted microscope. Custom-built environmental controls are used to maintain the temperature, humidity, and gas conditions for extended live cell work. The software was designed using Visual C++ for the Windows PC platform using an object orientated and modular design methodology to allow the BAMBI software to continue to grow with new tasks and demands as needed. The modular approach keeps functional groups of code within context boundaries allowing for easy removal, addition, or changes of functions without compromising the usability of the whole system. BAMBI has been used to image cells within a novel cell culture chamber that constricts cell growth to a true monolayer for high-resolution imaging. In one specific application, BAMBI was also used to characterize and track the development of individual Colony Forming Units (CFU) over the five-day culture period in 5-day CFU-Hill colony assays. The integrated system successfully enabled the tracking and identification of cell types responsible for the formation of the CFU-Hill colonies (a putative endothelial stem cell). BAMBI has been used to isolate single hematopoietic stem cell (HSC) candidate cells, accumulate long-term live cell images, and then return these cells back to the in-vivo environment for further characterization. From these results, further data mining and lineage informatics suggested a novel way to isolate and purify HSCs. Studies such as these are the fundamental next step in developing new therapies for regenerative medicine in the future.

An experimental study on the application of Digital Image Correlation (DIC) to measure the deformation and strain of rotating blades is described. Commercial DIC software was used to obtain measurements on three different types of rotors with diameter ranging from 18 to 39 and with varying flexibility to explore applicability of the technique over a breadth of scales. The image acquisition was synchronized with the frequency of rotation such that images could be obtained at the same phase and the consistency of measurements was observed. Bending and twist distributions were extracted from the data with deformation as high as 0.4 measured with a theoretical accuracy of 0.0038 and span-wise resolution of 0.066. The technique was demonstrated to have many advantages including full-field high resolution results, non-intrusive measurement, and good accuracy over a range of scales. The span-wise deformation profiles from the DIC technique are used in conjunction with Blade Element Momentum Theory to calculate the thrust and power consumed by the rotor with rigid vi blades; results are comparable to load cell measurements albeit thrust is somewhat under-predicted and power is over-predicted. Overall, the correlation between DIC calculated thrust and BEMT approximations for comparable blades with constant pitch were within 12% through the onset of stall. Measurement of flexible blade deformation that would not have been possible with other techniques demonstrated the utility of the DIC method and helped to confirm predictions of flexible blade behavior. / text

Devant le défi grandissant de diminuer la libération dans l'atmosphère des gaz à effet de serre plusieurs solutions ont été envisagées. Une des plus étudiée est le stockage géologique du CO2 par injection dans des aquifères salins profonds. Ces structures géologiques sont présentes dans les bassins sédimentaires et se caractérisent par leur épaisseur (plusieurs centaines de mètres) et leur étendue géographique (l'ensemble du bassin parisien, par exemple, pour la couche du Dogger). Le second interêt de ces structures est que les roches carbonatées qui les composent sont généralement très poreuses (10 à 30% de porosité) et présentent une perméabilité suffisamment élevée pour faciliter l'injection de fluides. Cependant, le comportement et l'évolution à long terme de ces réservoirs, après l'injection de CO2 dans la saumure en place, est incertain. Aussi, la résistance mécanique et les propriétés d'écoulement de ces roches sont étudiées pour réaliser des modèles prédictifs d'évolution, afin de garantir l'intégrité et la pérennité des sites de stockage. Le travail de cette thèse repose sur un protocole d'acidification retardée, développé et utilisé à l'IFPEN, permettant une altération homogène d'échantillons de carbonates. Notre objectif a été de déterminer les effets de ce type d'altération sur le comportement hydromécanique de la roche calcaire de Lavoux. La caractérisation des propriétés d'écoulement de la roche a été combinée à une étude microstructurale. Les paramètres étudiés sont la porosité et la perméabilité avant et après altération. Les résultats d'évolution de la perméabilité ont été analysés en s'appuyant sur une méthode de soustraction d'images de microtomographie RX, qui permet de visualiser la mobilité de particules fines au sein du réseau poreux. Ces dernières sont aussi révélées à postériori dans les effluents par diffraction laser. L'étude microstructurale de la roche après altération a permis la mise en évidence des mécanismes de dissolution et d'altération. Le comportement mécanique de notre roche à différents stades d'altération a été étudié à l'aide d'essais triaxiaux classiques réalisés à différents états de confinement. Ces essais ont montré que l'altération induit une transition du domaine de rupture fragile vers le domaine de rupture ductile. Afin de mieux comprendre ce comportement, nous avons mené des essais mécaniques uniaxiaux avec observation et acquisition d'images numériques " in-situ " : i) sur une presse électromécanique classique équipée de caméras CCD et de microscopie optique, ii) à l'aide d'un dispositif de compression miniaturisé adapté à l'enceinte d'un microscope électronique à balayage. La technique de corrélation d'images numériques a pu être appliquée tout au long du chargement mécanique à différentes échelles, depuis celle de l'échantillon, jusqu'à celle de la microstructure. Les mesures de champs de déformation ainsi réalisées ont permis de mettre en évidence les modes d'endommagement et de rupture selon l'état d'altération. Une cellule triaxiale miniaturisée pour être montée dans l'enceinte du microtomographe a spécialement été développée à l'IFPEN pour cette étude. Cette cellule nous a permis de mener des essais à 5 et 10 MPa de confinement avec observation volumique " in-situ " par tomographie. Nous avons pu identifier pour trois états d'altération, trois types de comportements à la rupture, avec l'observation i) d'une bande de cisaillement en régime de rupture fragile, ii) d'une étroite bande de cisaillement en compaction, iii) d'une large bande de compaction en cisaillement. L'ensemble des résultats obtenus sur les propriétés mécaniques et sur les propriétés d'écoulement (notamment la variation de perméabilité et la présence de fines dans le réseau poreux) tend à montrer que l'altération affecte fortement la microporosité du calcaire, avec des conséquences quant au comportement cisaillant compactant de notre roche.

Present state of art related to biomass conversion technology so far was found to concentrate on an enzymatic process, coupled with thermal pretreatment on biomass rich in cellulose. Biomass that rich in crude starch is also important in terms of strategic and economic point of view. The main objective of this study is to adopt a new strategy for a single step conversion of a crude starch material into oligosaccharide and glucose utilizing DIC technology. In contrast to existing thermal based pretreatment, DIC technology involves two vacuum cycles; first vacuum cycle was to increase steam accessibility on biomass and to reduce generation of steam condensate thus avoid losing of monosaccharide and hemicelluloses, while second vacuum cycle was to reduce potential thermal degradation of glucose. Distributions of products formed were found to be closely associated with severity of treatment on crude starch material. At lower DIC severity, pretreatment favors the formations of high oligosaccharide composition with small fraction of glucose; while at high DIC severity, pretreatment favors formation of high glucose as a major end product. During an exploratory study to establish the relevant reaction factors; vacuum cycle and moisture content were the two main factors influencing the conversion of crude starch into glucose.DIC starch conversion into glucose was found to be moisture dependent. Both factors were combined together to optimize the other three factors: pressure/temperature, treatment times, and acid concentration. High DIC severity treatment alone could convert nearly 50% of crude starch into glucose. During DIC optimization, an experimental design was developed and tested with DIC pretreatment in order to obtain a second order polynomial mathematical model that was then applied for response surface methodology (RSM). The interaction nature of above factors was examined and was found they depend on DIC treatment severity. Two experimental designs with low and high DIC severity were developed; Low DIC severity (acid: 0.01-0.05 molar, time: 0.5-3.0 min) and High DIC severity (acid: 0.05-0.20 molar, time: 3.0-10.0 min) with similar temperature range (144-165oC) were used. Data mining operation was done on RSM model to develop a kinetic model at both treatment severities. Kinetic data, including rate constant and activation energy were calculated from kinetic models of both severities to compare with actual dilute acidhydrolysis kinetic studies on two DIC treated samples. It was found that activation energy (Ea)for glucose generation at High DIC severity (Ea: 59.44 kJ/mol) was lower than at optimum dilute acid hydrolysis (Ea: 91.30 kJ/mol); while for glucose degradation, Ea was higher with High DIC severity (Ea: 144.12 kJ/mol) if compared to dilute acid hydrolysis (Ea: 45.14 kJ/mol).This indicates that glucose generation with DIC requires less energy while its degradation needs high energy. This combination was required to maximize glucose generation and minimize glucose degradation. Further studies with non-isothermal state during DIC and dilute acid hydrolysis support this finding. In normal polysaccharide conversion to low molecular weight (LMW) oligosaccharides and glucose procedures; two process steps were involved, namely the first process involved thermal pretreatment followed by a second process with dilute acid hydrolysis. In the present work, attempt was made to exclude dilute acid hydrolysis stage in order to establish that DIC process alone is sufficient for total polysaccharides conversion into LMW mainly glucose fraction. Information gathered from quantitative and statistical analysis on (i) exploratory studies, (ii) kinetic models from RSM of DIC process and (iii) kinetic data based on experimental works during dilute acid hydrolysis study; support the assumption that DIC treatment alone is sufficient for the total conversion required.

Present state of art related to biomass conversion technology so far was found to concentrate on an enzymatic process, coupled with thermal pretreatment on biomass rich in cellulose. Biomass that rich in crude starch is also important in terms of strategic and economic point of view. The main objective of this study is to adopt a new strategy for a single step conversion of a crude starch material into oligosaccharide and glucose utilizing DIC technology. In contrast to existing thermal based pretreatment, DIC technology involves two vacuum cycles; first vacuum cycle was to increase steam accessibility on biomass and to reduce generation of steam condensate thus avoid losing of monosaccharide and hemicelluloses, while second vacuum cycle was to reduce potential thermal degradation of glucose. Distributions of products formed were found to be closely associated with severity of treatment on crude starch material. At lower DIC severity, pretreatment favors the formations of high oligosaccharide composition with small fraction of glucose; while at high DIC severity, pretreatment favors formation of high glucose as a major end product. During an exploratory study to establish the relevant reaction factors; vacuum cycle and moisture content were the two main factors influencing the conversion of crude starch into glucose.DIC starch conversion into glucose was found to be moisture dependent. Both factors were combined together to optimize the other three factors: pressure/temperature, treatment times, and acid concentration. High DIC severity treatment alone could convert nearly 50% of crude starch into glucose. During DIC optimization, an experimental design was developed and tested with DIC pretreatment in order to obtain a second order polynomial mathematical model that was then applied for response surface methodology (RSM). The interaction nature of above factors was examined and was found they depend on DIC treatment severity. Two experimental designs with low and high DIC severity were developed; Low DIC severity (acid: 0.01-0.05 molar, time: 0.5-3.0 min) and High DIC severity (acid: 0.05-0.20 molar, time: 3.0-10.0 min) with similar temperature range (144-165oC) were used. Data mining operation was done on RSM model to develop a kinetic model at both treatment severities. Kinetic data, including rate constant and activation energy were calculated from kinetic models of both severities to compare with actual dilute acidhydrolysis kinetic studies on two DIC treated samples. It was found that activation energy (Ea)for glucose generation at High DIC severity (Ea: 59.44 kJ/mol) was lower than at optimum dilute acid hydrolysis (Ea: 91.30 kJ/mol); while for glucose degradation, Ea was higher with High DIC severity (Ea: 144.12 kJ/mol) if compared to dilute acid hydrolysis (Ea: 45.14 kJ/mol).This indicates that glucose generation with DIC requires less energy while its degradation needs high energy. This combination was required to maximize glucose generation and minimize glucose degradation. Further studies with non-isothermal state during DIC and dilute acid hydrolysis support this finding. In normal polysaccharide conversion to low molecular weight (LMW) oligosaccharides and glucose procedures; two process steps were involved, namely the first process involved thermal pretreatment followed by a second process with dilute acid hydrolysis. In the present work, attempt was made to exclude dilute acid hydrolysis stage in order to establish that DIC process alone is sufficient for total polysaccharides conversion into LMW mainly glucose fraction. Information gathered from quantitative and statistical analysis on (i) exploratory studies, (ii) kinetic models from RSM of DIC process and (iii) kinetic data based on experimental works during dilute acid hydrolysis study; support the assumption that DIC treatment alone is sufficient for the total conversion required.

The presence of residual stresses in engineering components may significantly affect damage evolution and progression towards failure. Correct evaluation of residual stress is of crucial importance for assessing mechanical components, predicting response and ensuring reliability. For example, when failure occurs due to cyclic loading, the underlying damage begins at the nano-, and then micro-scale. It is clear that improving engineering reliability at the micro-scale requires the ability to evaluate residual stress and mechanical properties at the appropriate scale. The key objective of the thesis is to advance the understanding and practice of residual stress evaluation at the micro-scale, and to examine the implications and applications that follow. Significant effort was devoted to the evaluation of two aspects of the relatively novel FIB-DIC micro-ring-core experimental technique: assessing the effects of Ga-ion damage and the quantification of uncertainty in stress evaluation due to unknown crystal orientation. FIB-DIC micro-ring-core milling was then used alongside with synchrotron XRD to study residual stress effects on fatigue crack growth propagation rate following the occurrence of overload or underload. The effects of the two principal mechanisms of crack retardation following an overload, residual stress and crack closure, were separated by testing samples at different loading ratios. Whilst, the acceleration after an underload was studied using validated non-linear FEM analyses. Conceptual focus was placed on the macro-micro-nano residual stress decomposition into Type I, II & III according to scale and, detailed examination was conducted experimentally and numerically. In the context of shot-peening surface treatment, residual stresses were modelled using a novel eigenstrain-based modelling procedure for arbitrarily shaped components. Furthermore, a fine scale characterisation was performed of the recast layer produced by EDM, with particular attention paid to the residual stress. The investigations presented in this thesis open new perspectives for the assessment of material reliability. Improved failure prediction models will be elaborated based on the insights obtained in the present study.

Made available in DSpace on 2016-06-02T20:06:08Z (GMT). No. of bitstreams: 1 DissRGC.pdf: 2581095 bytes, checksum: 4a2f54d065969def7422a978d84a16f4 (MD5) Previous issue date: 2005-02-24 / The proteins are important molecules from the cells, whereas they take part since the construction of cell´s framing until the transmission of the genetic information between the generations. A protein can be characterized by its function and its function is determined by the sequence of amino acids that determines its structure. To determined the protein's function is important, for instance, in a research about the cure of diseases or searching for new drugs. In this research we use a bayesian statistical methodology with mixture of multinomial and latent variables to identify proteins with similar function. We use simulations to verify the performance of the statistical model for identifying the similar proteins. At the end we apply the modeling to a real data set. / As proteínas são moléculas importantes das células, pois participam desde a construção das estruturas celulares até a transmissão de informações genéticas entre gerações. Uma proteína pode ser caracterizada pela sua função, sendo que esta função é determinada pela sequência de aminoácidos que compõe a sua estrutura. Determinar a função protéica é importante quando, por exemplo, se pesquisa a cura de doenças ou se pesquisa a fabricação de novos medicamentos. Neste trabalho utilizamos uma metodologia bayesiana de inferência estatística para inferir sobre o modelo com mistura de distribuições multinomiais e variáveis latentes para identificar proteínas com funções similares. Verificamos a performance da modelagem proposta em separar em grupos as proteínas com funções similares através de simulação.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-13T12:23:37Z No. of bitstreams: 1 IsaacJalesCostaSouza_DISSERT.pdf: 808186 bytes, checksum: 0218f6e40a4dfea5b56a9d90f17e0bfb (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-23T13:11:35Z (GMT) No. of bitstreams: 1 IsaacJalesCostaSouza_DISSERT.pdf: 808186 bytes, checksum: 0218f6e40a4dfea5b56a9d90f17e0bfb (MD5) / Made available in DSpace on 2017-01-23T13:11:35Z (GMT). No. of bitstreams: 1 IsaacJalesCostaSouza_DISSERT.pdf: 808186 bytes, checksum: 0218f6e40a4dfea5b56a9d90f17e0bfb (MD5) Previous issue date: 2016-01-28 / Neste trabalho ? apresentada uma abordagem bayesiana dos modelos pot?ncia normal bimodal (PNB) e pot?ncia normal bimodal assim?trico (PNBA). Primeiramente, apresentamos o modelo PNB e especificamos para este prioris n?o informativas e informativas do par?metroque concentra a bimodalidade (?). Em seguida, obtemos a distribui??o a posteriori pelo m?todo MCMC, o qual testamos a viabilidade de seu uso a partir de um diagn?stico de converg?ncia. Depois, utilizamos diferentes prioris informativas para ? e fizemos a an?lise de sensibilidadecom o intuito de avaliar o efeito da varia??o dos hiperpar?metros na distribui??o a posteriori. Tamb?m foi feita uma simula??o para avaliar o desempenho do estimador bayesiano utilizando prioris informativas. Constatamos que a estimativa da moda a posteriori apresentou em geralresultados melhores quanto ao erro quadratico m?dio (EQM) e vi?s percentual (VP) quando comparado ao estimador de m?xima verossimilhan?a. Uma aplica??o com dados bimodais reais foi realizada. Por ?ltimo, introduzimos o modelo de regress?o linear com res?duos PNB. Quanto ao modelo PNBA, tamb?m especificamos prioris informativas e n?o informativas para os par?metros de bimodalidade e assimetria. Fizemos o diagn?stico de converg?ncia para o m?todo MCMC, que tamb?m foi utilizado para obter a distribui??o a posteriori. Fizemos uma an?lise de sensibilidade, aplicamos dados reais no modelo e introduzimos o modelo de regress?o linear com res?duos PNBA. / In this paper it is presented a Bayesian approach to the bimodal power-normal (BPN) models and the bimodal asymmetric power-normal (BAPN). First, we present the BPN model, specifying its non-informative and informative parameter ? (bimodality). We obtain the posterior distribution by MCMC method, whose feasibility of use we tested from a convergence diagnose. After that, We use different informative priors for ? and we do a sensitivity analysis in order to evaluate the effect of hyperparameters variation on the posterior distribution. Also, it is performed a simulation to evaluate the performance of the Bayesian estimator using informative priors. We noted that the Bayesian method shows more satisfactory results when compared to the maximum likelihood method. It is performed an application with bimodal data. Finally, we introduce the linear regression model with BPN error. As for the BAPN model we also specify informative and uninformative priors for bimodality and asymmetry parameters. We do the MCMC Convergence Diagnostics, which is also used to obtain the posterior distribution. We do a sensitivity analysis, applying actual data in the model and we introducing the linear regression model with PNBA error.

Com os crescentes movimentos ecolÃgicos em todo o mundo, onde o objetivo principal visa conscientizar e estimular a populaÃÃo mundial a poupar os recursos naturais, aliado a necessidade de se desviar os resÃduos aterrados (sanitÃrios ou industriais), de forma a reduzir os problemas ambientais e de saÃde pÃblica, decorrentes da disposiÃÃo inadequada de resÃduos sÃlidos, surgem os incentivos a reciclagem de materiais, bem como o desenvolvimento de materiais biodegradÃveis. Diante deste contexto, os materiais compÃsitos reforÃados com fibras naturais ganham destaque no meio cientÃfico. No entanto, seu uso ainda à tido com desconfianÃa, devido ao pouco ou nenhum conhecimento desses promissores materiais. Perante essa problemÃtica, surgiu a proposta deste trabalho de carÃter investigativo, em que foi pesquisado e desenvolvido um compÃsito totalmente reciclado, de matriz termoplÃstica (PVC reciclado) reforÃado, com fibras obtidas da casca de cocos verdes descartados. Para esse objetivo foram utilizadas diversas ferramentas de caracterizaÃÃo fÃsica, quÃmica, tÃrmica e mecÃnica, sendo os valores dos campos de deformaÃÃo obtidos pela CorrelaÃÃo de Imagem Digital (CID), comparando a imagem do corpo nÃo deformado com imagens do corpo deformado. E finalmente, avaliou-se os processos de danificaÃÃo do compÃsito, atravÃs da caracterizaÃÃo experimental da evoluÃÃo do dano isotrÃpico pelos mÃtodosda variaÃÃo do MÃdulo de Elasticidade efetivo (ensaio de traÃÃo com carga e descarga) e pelo Ãndice de Tsai-Wu com os parÃmetros constitutivos da funÃÃo tangente hiperbÃlica, onde os valores encontrados, em ambos os mÃtodos, mantiveram-se dentro da faixa esperada para compÃsitos, 0,20 â 0,50. / With increasing the ecological movements around the world, whose the main objective aims to raise awareness and encourage the world's population to save natural resources, coupled with the need to divert grounded waste (sanitary or industrial) in order to reduce environmental problems and public health, arising f rom the improper disposal of solid waste, emerge incentives for recy cling, and the development of biodegradable materials. Given this context, the composites reinforced with natural fibers began to be highlighted in the scientific community. However, its utilization is still seen with suspicion due to little or no knowledge of these pr omising materials. Faced with this problem, arose the proposal of this investigative character work, in with it was researched and devel oped a fully recycled composite, of thermoplastic matrix (recycl ed PVC) reinforced with fibers obtained from the bark of green coconut s discarded. For this objective were used various tools of physical, chemical, thermal and mechanical characterization, whose amounts of d eformation fields were obtained by Digital Image Correlation (DIC), c omparing the image of the body not deformed with images of the deforme d body. Finally, we assessed the processes of damage of the composite, through experimental characterization of the evolution of t he isotropic damage by the methods of varying the effective elastic mod ulus (tensile test with loading and unloading) and by Tsai-Wu index wi th the parameters constitutive of hyperbolic tangent function, where the values found, in both methods, were within the expected range for composite, from 0.20 to 0.50.