Sepse é a resposta inflamatória sistêmica do hospedeiro à infecção, que pode ser desencadeada por bactérias, vírus ou fungos. Há aumento da produção de mediadores inflamatórios como citocinas, quimiocinas espécies reativas de oxigênio e do recrutamento de neutrófilos. A administração de solução salina hipertônica 7,5% (SH) acarreta na modulação da resposta inflamatória e hemodinâmica culminando na redução da morbidade e mortalidade em modelos de pancreatite e choque hemorrágico. No presente trabalho, estudamos os efeitos da SH na sepse, induzida por ligadura e perfuração cecal (CLP) em camundongos Balb/C, divididos em 3 grupos: CLP sem nenhum tratamento (CLP); CLP tratado com solução salina isotônica 0,9% (SS) e CLP tratado com SH 7,5% (SH); um quarto grupo foi utilizado como controle, no qual não foi induzido sepse ou administrado tratamento (C); ambos os tratamentos foram aplicados 30 min. após CLP. Lavado peritoneal, intestino e pulmão foram coletados após 6h, 12h e 24h para a análise de citocinas (TNF-, IL-6 e IL-10), produção de oxido nítrico, peroxidação lipídica, infiltração de neutrófilos, moléculas de adesão (ICAM-1 e VCAM-1) e quimiocinas (CXCL-1). O grupo SH mostrou aumento de sobrevida (60%) em comparação aos grupos SS (46,6%) e CLP (33,3%) após 168h. SS apresentou aumento na produção de TNF- (27,3 ± 3,05 pg/ml) em 12h comparado ao grupo CLP (14,07 ± 1,68 pg/ml) e SH (19,66±3,19pg/ml); O efeito da SH na concentração de TNF permanece até 24h (6,2 ± 3,5 pg/ml vs. CLP 73,40± 49,52 pg/ml); a produção de IL-10 em 24h aumentaram nos grupos CLP (CLP - 3,12 ± 0,46 pg/ml) e SS (2,9 ± 0,9 pg/ml) em relação ao grupo SH (0,59 ± 0,34 pg/ml). Em 24h a produção de nitrito mostrou-se reduzida no grupo SH (6,77 ± 0,82 pg/ml) comparado com SS (10,65 ± 1,08 pg/ml), no pulmão. No intestino, a produção de nitrito, em 6h, diminuiu no grupo SH (1,27 ± 0,19 pg/ml) comparado com CLP (2,44 + 0,51 pg/ml). No grupo SH houve redução do infiltrado de neutrófilos no pulmão em 24h, através da redução de moléculas de adesão e concentração de mieloperoxidase, em comparação com CLP (29,4 + 5,7 ng/mg ; 3,02 + 0,41 mU/mg). Nossos resultados indicam que SH modula a resposta inflamatória, além de melhorar a sobrevida de animais submetidos à sepse experimental / Sepsis is a systemic inflammatory response to infection triggered by bacteria, virus and fungi. There is a rise in inflammatory mediators as citokynes, chemokynes, reactive oxygen species and neutrophil recruitment (1). The hypertonic saline solution (SH) has been showed to improve hemodynamic and inflammatory response. We studied the hypertonic solution effects in sepsis through cecal ligation and puncture (CLP) in mice Balb-C, divided in 3 groups: CLP without treatment (CLP); CLP treated with isotonic saline solution 0,9% - 34mg/Kg (SS); CLP treated with hypertonic saline solution 7,5% - 4ml/Kg (SH); and a 4th group indicating the basal values without both CLP and treatment (C); both treatments were administrated 30 min after CLP. The lung, gut and peritoneal fluid were collected after 6h, 12h and 24h to analyze cytokines levels, oxide nitric, lipid peroxidation and neutrophil infiltration. The SH group showed higher survival rats (60%) when compared to SS (46,6%) and CLP (33,3%) after 168h (7 days). TNF- level in the SS group (27,3 ± 3,05 pg/ml) was increased at 12h when compared to CLP (14,07 ± 1,68 pg/ml) and SH (19,66±3,19pg/ml); and at 24h the SH (6,2 ± 3,5 pg/ml) decreased its level when compared to CLP (73,40± 49,52 pg/ml); IL-10 level at 24h was increased in CLP (CLP - 3,12 ± 0,46 pg/ml) and SS (2,9 ± 0,9 pg/ml) in relation to SH (0,59 ± 0,34 pg/ml). In 24h, the quantification of nitrite decreased in SH (6,77 ± 0,82 pg/ml) compared with SS (10,65 ± 1,08 pg/ml) in lung. In intestine, nitrite levels diminished in SH (1,27 ± 0,19 pg/ml) in relation to CLP (2,44 + 0,51 pg/ml) in 6h. SH group reduced the neutrophil infiltration in lung, through adhesion molecule and myeloperoxidase at 24h (ng/mg;1,49 + 0,24 mU/mg) in relation to CLP(29,4 + 5,7 ng/mg ; 3,02 + 0,41 mU/mg). Our results suggest that the volume replacement of both treatments modulate pro and anti-inflammatory mediators of an inflammatory response to infection, but hypertonic solution presented a more effective effect

O terraceamento é uma prática de conservação do solo que visa reduzir a perda de água e solo pela interceptação de enxurradas que ocorrem quando a intensidade da chuva supera a capacidade de infiltração de água no solo. Atualmente, o dimensionamento dos terraços tem sido feito com base em conhecimento empírico; no entanto, um conhecimento mais detalhado da física dos processos que regem o funcionamento dos terraços possibilitaria otimizar o dimensionamento dos terraços. No presente estudo foi avaliada a capacidade de infiltração de água no canal de um terraço em nível pelos métodos da densidade de fluxo e da armazenagem de água em diferentes condições de manejo agrícola (solo nu, solo gramado e solo sob preparo convencional e plantio direto para a implantação da cultura de milho) num Latossolo vermelho com declividade média de 0,08 m m-1. Em cada tratamento foram instaladas sondas de TDR em três pontos de observação no centro do canal do terraço (distanciados de 4 m entre si e considerados como repetições), nas rofundidades de 0,05, 0,10, 0,20, 0,40, 0,60 e 0,80 m. Nestas mesmas profundidades amostras indeformadas de solo foram retiradas para determinação da densidade e curva de retenção de água no solo. As leituras das guias de onda do TDR foram feitas automaticamente e a intensidade de chuva monitorada por um pluviômetro automatizado. Ao final de cada evento de chuva erosiva a deposição de solo foi medida por meio de 14 pontos de observação dispostos ao longo do centro do canal do terraço de cada tratamento. Durante a estação seca (julho-agosto), a condutividade hidráulica do solo não saturado foi determinada em cada repetição nas mesmas profundidades, utilizando o método do perfil instantâneo. Os resultados demonstraram que os manejos agrícolas influenciam na deposição de água e solo sobre o canal do terraço e estas na formação de selo superficial e na capacidade de infiltração de água do canal. Conclui-se que a alta variação comumente obtida entre as repetições de determinação da condutividade hidráulica implica em dificuldades quando se objetiva detectar pequenas diferenças nas densidades de fluxo entre tratamentos. Assim, mostrou ser inviável utilizar densidades de fluxo calculadas pela equação de Darcy-Buckingham para encontrar diferenças em taxas de infiltração em terraços em nível. Essa conclusão reforça-se devido às condições superficiais altamente variáveis encontradas em canais de terraços em nível devido a deposições irregulares do material erodido. Uma metodologia para se realizar medições da umidade nas deposições sobre o canal deve ser desenvolvida para aumentar a acurácia da medida da armazenagem. A taxa de infiltração de água no canal do terraço não pode ser estimada pela variação da armazenagem da água no solo somente, devido ao papel importante da drenagem profunda e, possivelmente, da absorção de água pela camalhão do terraço. Uma adequada estimativa da taxa de infiltração no canal do terraço, imprescindível para seu dimensionamento, deve aliar um grande número de repetições, além da medição da umidade no interior da camada de material depositado sobre o canal ao longo do tempo. / Terracing is a soil conservation practice that aims to reduce water and soil loss by interception of runoff that occurs when rainfall intensities exceed infiltration capacity. Actually, dimensions of terraces are being determined in an empirical way; however, a more detailed understanding of the physics behind the hydrological functions of terraces would allow an optimized dimensioning of terraces. In this study the infiltration capacity of a level terrace was evaluated by the methods of flux density and water storage, under different management conditions (bare soil, pasture, conventionally tilled maize and zero-tillage maize) on an oxisol with a slope of 0.08 m m-1. In each treatment TDR sensors were installed at three observation points in the middle of the terrace canal (distance between points: 4 m; considered to be repetitions) at the depths of 0.05, 0.10, 0.20, 0.40, 0.60 and 0.80 m. At the same depths, undisturbed soil samples were taken to determine soil density and soil water retention curve. TDR readings were made automatically and a rainfall gauge automatically monitored rainfall intensity. At the end of each rainfall event, soil deposition was measured at 14 locations in the terrace canal in each treatment. During the dry season (July-August), unsaturated hydraulic conductivity was determined at each repetition at the same depths by the instantaneous profile method. The results showed that agricultural management influenced water and soil deposition in the terrace canal and these affected surfaced sealing and infiltration capacity. It was concluded that the high variation usually obtained between repetitions of the hydraulic conductivity determinations makes the detection of small differences between flux densities difficult. Therefore, it showed to be impossible to use flux densities calculated by Darcy-Buckingham equation in the order to prove existence of different infiltration rates in level terraces. This conclusion was reinforced due to the highly variable surface conditions in the terrace canal. A methodology to measure water contents within the depositions in the canal should be developed to increase the precision of water storage estimation. Infiltration rates in the terrace canal cannot be estimated by storage variation alone, due to the important role of drainage and, possibly, ascension of water in the terrace hill. A correct estimate of the infiltration rate in the canal, necessary for its dimensioning, should combine a high number of repetitions with the measurement of water content within the layer of deposits over the terrace canal surface along time.

A combinação entre a falta de planejamento urbano e o crescimento indiscriminado de áreas impermeáveis é responsável pela ocorrência de enchentes em centros urbanos. O emprego de dispositivos de controle do escoamento superficial na fonte geradora, como poços e trincheiras de infiltração, pavimentos permeáveis e jardins de infiltração (rain gardens), é uma alternativa que permite restabelecer o processo de infiltração em áreas urbanas densamente impermeabilizadas. Neste contexto, efetuou-se uma análise paramétrica acerca da influência das funções condutividade hidráulica e das curvas de retenção dos solos no processo de infiltração de água em poços cilíndricos instalados em solos inicialmente não saturados. Para a realização das análises paramétricas, foi empregado o programa SEEP/W do pacote GeoStudio 2004, que utiliza a técnica dos elementos finitos na solução numérica da equação de Richards que rege o fluxo de água em meio não saturado. As análises paramétricas mostraram que o coeficiente de condutividade hidráulica saturada do solo é o parâmetro que apresenta maior relevância no processo de infiltração de água em poços. Com isto, desenvolveu-se uma técnica de dimensionamento de poços de infiltração que permite determinar o volume de água infiltrada em um dado poço em função do tempo de precipitação, do coeficiente de condutividade hidráulica saturada do solo e da área total do poço. Por fim, comparou-se o volume estimado de água infiltrada obtido através da técnica de dimensionamento com o volume medido em um ensaio de infiltração realizado por Lima (2009) em uma trincheira de pequenas dimensões e pôde-se constatar que o a técnica de dimensionamento desenvolvida é consistente com o ensaio de infiltração realizado em campo. / The chief consequence of unplanned urban sprawl is the turning to impervious large tracts of land. Impervious developed areas are prone to floods during heavy rains. Flooding may be mitigated by installation of devices that can control runoff at the source. Examples of control devices are infiltration wells, infiltration trenches, permeable pavement, and rain gardens. By facilitating infiltration, such devices serve to return to the soil below the waterproofed area the waters that would otherwise be lost as runoff, which overloads urban drainage. A study of infiltration wells was conducted through parametric analyses of hydraulic conductivity function and soil-water characteristics curve of unsaturated soils in the process of infiltration. This research used the computer program SEEP/W by GeoStudio 2004 to carry out the parametric analysis. SEEP/W uses the finite element method for the numerical solution of Richards equation, which describes water flow in the unsaturated zone. The parametric analysis showed that the saturated hydraulics conductivity of the soil is the parameter that has greater relevance in the process of infiltration of water into the soil surrounding the wells. Based on the results obtained, a technical procedure was developed to assist the consulting professional to size the infiltration wells. The variables employed in the proposed design procedure consist of time of precipitation, saturated hydraulic conductivity, and total surface area of well. Further, it was compared the estimated volume of infiltrated water obtained through this procedure to the measured volume obtained by Lima (2009) in a small trench. It was observed that the scaling procedure proposed by this work yields results consistent with infiltration field experiments such as that conducted by Lima (2009).

A interface do implante com o componente protético geralmente apresenta lacunas que servem de nichos para a colonização bacteriana. A proposta deste estudo é verificar a eficácia do dimetacrilato na vedação desta interface. Foram utilizados 20 implantes ósseos Bone Level® Straumann, indicados para reabilitação protética unitária cimentada. Os pilares protéticos foram instalados nos grupos controle e experimental, adicionando-se o dimetacrilato à interface da conexão protética. Foram realizadas uma coleta inicial e uma coleta ao final do período de 90 dias no interior de cada implante, e através da técnica de PCR quantitativo foi analisada a infiltração e a detecção das espécies bacterianas Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia. No Grupo Controle, todas as amostras apresentaram quantificação de microrganismos, confirmando infiltração bacteriana. No Grupo Experimental, apenas 30% das amostras apresentou quantificação após o período estudado. Assim, a ausência de bactérias no Grupo Experimental foi associada ao tratamento com o dimetacrilato para o período. Quando considerada a presença de pelo menos uma das bactérias específicas estudadas nas amostras, a diferença também foi estatisticamente significante. Entretanto, mais estudos devem ser desenvolvidos a fim de verificar se a vedação será eficiente por períodos mais longos. / The implant/prosthetic component interface often has gaps that serve as niches for bacterial colonization. The purpose of this study is to verify the effectiveness sealing this interface with dimethacrylate. Twenty two Straumann ® Bone Level implants was installed in areas with indication for single cemented prosthetic rehabilitation. The prosthetic components were installed in the control and experimental groups following the fabricant instructions, and adding the dimethacrylate in the interface of the experimental group. An initial collection and a second collection at the end of 90 days within each implant were performed, and after that, the technique of quantitative PCR was developed to analyze whether there was infiltration and detection of four bacterial species: Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia. In the control group, all samples showed quantification of microorganisms, confirming bacterial percolation. In the control group, only 30% of the samples submitted quantification after the study period. Thus, the absence of bacteria in the experimental group was associated with the treatment for the period dimethacrylate. Considering the presence of at least one specific bacteria in the samples studied, the difference was also statistically significant. However, more studies should be conducted to verify that the seal will be effective for longer periods.

Thermal barrier coatings (TBC) are used in the hot sections of gas turbine engine in order to insulate the substrate at high temperature. Molten salt infiltration retards the durability of TBCs. The current standard material, i.e. 8YSZ is susceptible to molten salt infiltration. Therefore, alternate TBC materials are desirable. In addition to material composition, the TBC microstructure plays an important role in mitigating molten salt infiltration. Therefore, in this work, three different TBC variations were investigated. The first variation was a columnar microstructured 48YSZ TBC processed by SPS (48YSZ-SPS). The second variation was a columnar microstructured 8YSZ TBC processed by SPS (8YSZ-SPS), and the third variation was a lamellar microstructured 8YSZ TBC deposited by APS (8YSZ-APS). The as-sprayed TBC specimens were characterized by SEM/EDS, porosity analysis and XRD measurements. Later, the TBC specimens were exposed to hot corrosion test and their interaction with the molten salts were investigated using SEM (EDS and XRD). It was shown that an increase in stabilizer content (yttria content) in zirconia (in the case of 48YSZ) leads to an improved hot corrosion resistance due to the adequate amount of yttria content, which restricts the molten salt infiltration by forming needle like YVO4 phase. In terms of microstructure comparison, the infiltration behavior was similar for columnar microstructured 8YSZ and lamellar microstructured 8YSZ-APS as the molten salts infiltrated the coatings completely compared to the 48YSZ TBC. Furthermore, it seems that the molten salt infiltrates the TBC through globular pores, delamination cracks and splat boundaries in the case of APS-TBCs whereas the column gaps favor easier infiltration of molten salts in the case of columnar microstructured SPS processed TBCs.

I evaluated the effectiveness of plant roots to increase infiltration rates within stormwater bioretention facilities (SBFs), roadside planter compartments that filter stormwater. SBFs attenuate harmful effects of stormwater by reducing peak flow and retaining pollutants, with increased infiltration that improves both these functions. Researchers have shown that roots can increase infiltration within greenhouse, lab, field, and test SBF settings. However, no researchers have yet measured either the extent to which different root characteristics can increase infiltration or the variation in root characteristics and their effect on infiltration rates among plant assemblages within currently functioning SBFs. To determine if root-enhanced infiltration was occurring within SBFs, I hypothesized 1) there is a relationship between root characteristics and infiltration during late spring, and 2) seasonal root growth increases infiltration rates. Within Portland, OR, I measured infiltration rate from January 2014 to February 2015 and root characteristics from January-February (J-F) and May-June (M-J) 2014 in ten SBFs with "Elk Blue" rush (Juncus patens) and 1 or 2 trees of less than 8.4 cm stem diameter. During M-J, four root characteristics showed a positive relationship with infiltration rate, and two root characteristics showed a strong positive relationship with infiltration rate within the topsoil. Also, a relationship was shown between the increase (J-F to M-J 2014) in three root characteristics and the increase in infiltration rate. To determine if root morphology and infiltration rates differed among SBFs with two different dominant vegetation taxa (small and large root biomass), I hypothesized 3) Juncus patens and tree dominant assemblage (greater root biomass) exhibits greater infiltration compared to the Carex dominant assemblage, 4) the increase in infiltration rate and root characteristics from J-F to M-J is greater in the Juncus compared to the Carex assemblage, and 5) root surface area density (RSAD) within Juncus SBFs shows a positive relationship with infiltration rate in late spring. I measured infiltration rate from January 2014 to February 2015 and root characteristics from January-February (J-F) and May-June (M-J) 2014 among five large-root (Juncus and tree) and five small-root biomass (Carex sp) SBFs. Juncus SBFs showed greater values for three root characteristics during J-F and five root characteristics during M-J 2014 compared to Carex SBFs. Also, Juncus SBFs showed an increase from J-F to M-J 2014 for five root characteristics while Carex SBFs showed no root increase. Juncus SBFs showed a relationship with four root characteristics and Carex SBFs a showed relationship with one root characteristic and infiltration rate. This work strongly suggests plant roots increase infiltration, and thus the primary functions of SBFs. Different root characteristics appear to increase infiltration rate at different depths. Data also show larger-root biomass plants increase infiltration rate to a greater degree than smaller-root biomass plants. I recommend considering several site and facility characteristics when determining the potential for root-enhanced infiltration. When selecting plant species to enhance infiltration, I recommend using several criteria, determining root characteristic values at certain depths, considering installation approaches, and accounting for regional climate changes.

The aim of the thesis is to find a method, in conjunction with the ordinary differential equation (ODE) based method of lines (MOL) solution of Richards’ equation, to model the steep wetting front infiltration in very dry soils, accurately and efficiently. Due to the steep pressure head or steep water volumetric content gradients, highly nonlinear soil hydraulic properties and the rapid movement of the wetting front, accurate solutions for infiltration into a dry soil are usually difficult to obtain. Additionally, such problems often require very small time steps and large computation times. As an enhancement to the used ODE/MOL approach, Higher Order Finite Differencing, Varying Order Finite Differencing, Vertical Scaling, Adaptive Schemes and Non-uniform Stretching Techniques have been implemented and tested in this thesis. Success has been found in the ability of Vertical Scaling to simulate very steep moving front solution for the Burgers’ equation. Unfortunately, the results also show that Vertical Scaling needs significant research and improvement before their full potential in routine applications for difficult nonlinear problems, such as Richard’s equation with very steep moving front solution, can be realized. However, we have also shown that the use of the composed form of RE and a 2nd order finite differencing for the first order derivative approximation is conducive for modelling steep moving front problem in a very dry soil. Additionally, with the combination of an optimal influx value at the edges of the inlet, the ODE/MOL approach is able to model a 2-D infiltration in very dry soils, effectively and accurately. Furthermore, one of the strengths of this thesis is the use of a MATLAB PDE template. Implementing the ODE/MOL approach via a MATLAB PDE template has shown to be most suitable for modelling of partial differential equations. The plug and play mode of modifying the PDE template for solving time-dependent partial differential equations is user-friendly and easy, as compared to more conventional approaches using Pascal, Fortran, C or C++. The template offers greater modularity, flexibility, versatility, and efficiency for solving PDE problems in both 1-D and 2-D spatial dimensions. Moreover, the 2-D PDE template has been extended for irregular shaped domains.

L'objectif de ce travail a été de proposer une méthode permettant d'augmenter la résistance à l'oxydation et à la corrosion par Si liquide des creusets de graphite utilisés dans la purification de Si métallurgique pour obtenir Si de qualité photovoltaïque. La Thèse est constituée de deux parties. Dans la première partie, nous étudions les interactions capillaires (mouillage, infiltration, réactivité) Si/graphite, et l'effet de ces interactions sur la pollution de Si et sur l'intégrité mécanique du graphite. Dans la deuxième partie nous mettons au point un traitement de siliciuration du graphite et nous montrons que ce traitement confère au graphite une résistance remarquable à l'oxydation à haute température

L'étude porte sur la recherche systématique de solutions analytiques et numériques de l'équation de l'infiltration monodimensionnelle de l'eau dans le sol. Dans une premièere partie les différents approches quasianalytiques sont analysées. La solution en série PHILIP, retenue dans cette étude est améliorée et complétée. Elles est ensuite utilisée comme base de référence pour tester les solutions numériques. Dans une seconde partie, un grand nombre de modèles numériques sont comparés afin d'essayer de dégager un ou plusieurs schémas présentant un optimum vis à vis des critères de convergence , précision et coût économique.

Ce travail vise à comprendre les relations qui existent entre, d'une part, les hétérogénéités lithologiques et structurales au sein d'un glissement argileux et, d'autre part, l'alimentation en eau des surfaces de glissement. Le site d'étude est le glissement d'Avignonet (Trièves, Alpes françaises), constitué d'argiles glaciolacustres würmiennes. Ce glissement, d'une surface d'environ 1.5 km², est situé à proximité immédiate de celui d'Harmalière qui a évolué en coulée boueuse en 1981. Plusieurs surfaces de glissement sont connues à des profondeurs variables (5, 10-15 et 40-50 m). Dans ces terrains saturés (en dehors de la frange superficielle), les vitesses moyennes de déplacement peuvent atteindre 0.15 m/an. Les observations géodésiques indiquent que, bien que situés dans des contextes géologique et météorologique identiques, les deux glissements ont des cinétiques différentes depuis les années 60 au moins. A l'aide d'outils géophysiques (bruit de fond, tomographies sismiques et électriques, diagraphies) couplés à des données géotechniques (forages, essais de laboratoire, analyses d'échantillons), géodésiques et météorologiques, il est possible de mettre en évidence une activité variable à différentes échelles au sein du glissement. À l'échelle régionale, le contexte morphologique conditionne la cinématique du mouvement de terrain. Les hétérogénéités lithologiques, au sein de la séquence argileuse, induisent un comportement hydrogéologique variable et, conséquemment, une cinétique différentielle en surface. Finalement, les hétérogénéités structurales, telles que les fissures dans une zone intensément déformée, servent de chemin d'infiltration préférentielle et permettent d'apporter rapidement de l'eau jusqu'à la nappe superficielle et aux surfaces de glissement à 10 m de profondeur.