Thesis (M.S.)--Michigan State University. Dept. of Chemical Engineering and Material Science, 2008. / Title from PDF t.p. (viewed on July 29, 2009) Includes bibliographical references (p. 34-41). Also issued in print.

Thesis (Ph. D.)--University of Missouri-Columbia, 2004. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2004. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.

abstract: The structural design of pavements in both highways and airfields becomes complex when one considers environmental effects and ground water table variation. Environmental effects have been incorporated on the new Mechanistic-Empirical Pavement Design Guide (MEPDG) but little has been done to incorporate environmental effects on airfield design. This work presents a developed code produced from this research study called ZAPRAM, which is a mechanistically based pavement model based upon Limiting Strain Criteria in airfield HMA pavement design procedures. ZAPRAM is capable of pavement and airfield design analyses considering environmental effects. The program has been coded in Visual Basic and implemented in an event-driven, user-friendly educational computer program, which runs in Excel environment. Several studies were conducted in order to insure the validity of the analysis as well as the efficiency of the software. The first study yielded the minimum threshold number of computational points the user should use at a specific depth within the pavement system. The second study was completed to verify the correction factor for the Odemark's transformed thickness equation. Default correction factors were included in the code base on a large comparative study between Odemark's and MLET. A third study was conducted to provide a comparison of flexible airfield pavement design thicknesses derived from three widely accepted design procedures used in practice today: the Asphalt Institute, Shell Oil, and the revised Corps of Engineering rutting failure criteria to calculate the thickness requirements necessary for a range of design input variables. The results of the comparative study showed that there is a significant difference between the pavement thicknesses obtained from the three design procedures, with the greatest deviation found between the Shell Oil approach and the other two criteria. Finally, a comprehensive sensitivity study of environmental site factors and the groundwater table depth upon flexible airfield pavement design and performance was completed. The study used the newly revised USACE failure criteria for subgrade shear deformation. The methodology utilized the same analytical methodology to achieve real time environmental effects upon unbound layer modulus, as that used in the new AASHTO MEPDG. The results of this effort showed, for the first time, the quantitative impact of the significant effects of the climatic conditions at the design site, coupled with the importance of the depth of the groundwater table, on the predicted design thicknesses. Significant cost savings appear to be quite reasonable by utilizing principles of unsaturated soil mechanics into the new airfield pavement design procedure found in program ZAPRAM. / Dissertation/Thesis / M.S. Civil and Environmental Engineering 2011

Submitted by Natalia de Souza Gonçalves (natalia.goncalves@ufpe.br) on 2016-10-10T12:17:42Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese Maralise-081214-VERSÃO corrigida biblioteca ATUALIZADA.pdf: 9951245 bytes, checksum: be34a8b4340d6e8daffcff6422e39f13 (MD5) / Made available in DSpace on 2016-10-10T12:17:42Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese Maralise-081214-VERSÃO corrigida biblioteca ATUALIZADA.pdf: 9951245 bytes, checksum: be34a8b4340d6e8daffcff6422e39f13 (MD5) Previous issue date: 2014-12-22 / síndrome de imunodeficiência adquirida (AIDS) é uma doença infecciosa e desde que foi descoberta nos EUA, em 1981, a AIDS se espalhou rapidamente, sendo considerada uma epidemia mundial caracterizada por uma imunodeficiência severa, infecções oportunistas, neoplasia e um resultado fatal. Apesar de já ser empregado a multiterapia anti-HIV, tal tratamento farmacológico traz como inconveniente resistência já relatada aos antivirais e a toxicidade provocada por esses fármacos. Dessa forma, é um desafio para os pesquisadores a busca por fármacos mais eficazes e menos tóxicos. A meta é minimizar o impacto dessa doença no Brasil e no mundo. Para tanto, conhecendo-se as propriedades dos tionucleosídeos, objetivou-se, no presente trabalho, a síntese, a caracterização e a avaliação da atividade antiviral e antitumoral de novos análogos tionucleosídeos da 5-metiluridina. A síntese dos análogos foi efetuada a partir de 2’,2-anidrotimidina. Reação deste composto com 2-(trimetilsilil)etanotiol na presença de carbonato de potássio, seguida da mesilação das hidroxilas de 3’ e 5’ forneceu o derivado dimesilado correspondente que, por reação com benzoato de sódio forneceu o tionucleosídeo 2’, 3’-didesidro correspondente, benzoilado em C-5’. Remoção do grupo benzoíla com hidróxido de potássio/metanol forneceu o nucleosídeo insaturado 2’,3’-didesidro-2’,3’-didesoxi-2’-(2-trimetilsilil)etiltio)timidina. Substituindo-se o 2-(trimetilsilil)etanotiol pelo tiometóxido de sódio o tionucleosídeo insaturado correspondente foi obtido. Quando o derivado anidro foi submetido a reação com hidreto de sódio em DMF, seguida da reação do epóxido formado com 2-(trimetilsilil)etanotiol, obteve-se um intermediário de configuração D-xilo, contendo a cadeia sulfurada em C-3’. Reação desse composto com carbonato de difenila em DMF, em presença de bicarbonato de sódio forneceu o derivado 2’,3’-insaturado correspondente, contendo o grupo fenoxicarbonila em C-5’. Esse intermediário foi convertido no tionucleosídeo insaturado correspondente de forma semelhante à descrita para a obtenção de 2’,3’-didesidro-2’,3’-didesoxi-2’-(2-trimetilsilil)etiltio)timidina. Também nesse caso, a substituição de 2-(trimetilsilil)etanotiol pelo tiometóxido de sódio levou, ao final da síntese, ao tionucleosídeo insaturado contendo o grupo metiltio em C-3’. Os produtos finais e alguns intermediários foram avaliados em testes de atividade citotóxica contra linhagem de células tumorais A549 (linhagem humana de câncer de pulmão). O intermediário 2’, 3’-didesidro benzoilado em C-5’ e derivado 2’,3’-insaturado contendo o grupo fenoxicarbonila em C-5’ destacaram-se entre os mais ativos da série, apresentando, respectivamente CC50 32,8 μM e 85,5 μM. Os testes de atividade contra o herpes vírus simplex humano tipo I (HSV-I) estão em andamento. Os testes contra o HIV serão realizados oportunamente. / Acquired immune deficiency syndrome (AIDS) is an infectious disease and since its discovery in the USA in 1981, AIDS has spread rapidly and is considered a global epidemic characterized by severe immunodeficiency, opportunistic infections, cancer and a fatal outcome. Despite being already employed an anti-HIV multi-therapy, pharmacotherapy has drawbacks like viral resistance to antiviral drugs and drug toxicity. Thus, it is a challenge for researchers the search for more effective and less toxic drugs.The goal is to minimize the impact of this disease in Brazil and worldwide. To that end, knowing the properties of thionucleosides, the aim of the present work was the synthesis, characterization and evaluation of antiviral and antitumor activity of novel thionucleosides analogues of 5-methyluridine. Analogues synthesis was performed from 2', 2-anhydrothymidine. Reaction of this compound with 2- (trimethylsilyl)ethanethiol in the presence of potassium carbonate, followed by mesylation of hydroxyl groups at 3' and 5' provided the corresponding mesylated derivative, which, by reaction with sodium benzoate, provided the corresponding 2',3'-didehydro, benzoylated at C-5'. Removal of benzoyl group with potassium hydroxide/methanol gave the unsaturated nucleoside 2',3'- didehydro-2',3'-dideoxy-2'-(2-trimethylsilyl)ethylthio)thymidine. Replacing 2- (trimethylsilyl)ethanethiol by sodium thiomethoxide, the corresponding unsaturated thionucleoside was obtained. When the anhydro derivative was subjected to reaction with sodium hydride in DMF, followed by reaction of the epoxide formed with 2-(trimethylsilyl)ethanethiol, a D-xylo intermediate, with the side chain at C-3' was obtained. Reaction of this compound with diphenyl carbonate in DMF in the presence of sodium bicarbonate provided the corresponding 2',3'-unsaturated derivative containing phenoxycarbonyl group at C-5'. This intermediate was converted to the corresponding unsaturated thionucleoside in a similar way to that described to obtain 2', 3'-didehydro-2',3'- dideoxy-2'- (2-trimethylsilyl)ethylthio)thymidine. Also in this case, replacing 2- (trimethylsilyl)ethanethiol by sodium thiomethoxide led to the unsaturated thionucleoside containing methylthio group at C-3'. Final and some intermediate compounds were evaluated for cytotoxicity activity against tumor cell line A549 (human lung cancer strain). 2',3'-didehydro thionucleoside benzoylated at C-5' and 2',3'-unsaturated thionucleoside containing phenoxycarbonile group at C-5' derivative were the most active compounds in this series, presenting CC50 values of 32.8 μM and 85.5 μM, respectively. Tests for antiviral activity against human herpes simplex virus type I (HSV-I) are in progress. Anti-HIV screening will be conducted in the near future.

1. The literature has been reviewed with respect to the dietary intake and subsequent metabolism of polyunsaturated fatty acids (PUFA), of both the n-6 and n-3 series, in teleost fish. Particular emphasis has been made to the physiological roles of PUFA with respect to cell membrane function and eicosanoid production. 2. Atlantic salmon post-smolts were fed practical-type diets, based on fish meal, in three separate dietary experiments of 10-16 weeks duration. The first trial compared dietary lipid supplied either as fish oil (FO) or as sunflower oil (SO) with the diets having an n-3/n-6 PUFA ratio of 9.4 and 0.2 respectively. The second trial used diets formulated with blends of FO, SO, grape seed oil and safflower oil to provide linoleic acid at 10, 25 and 45% of total dietary fatty acids. The third trial was similar to the first but with an additional diet in which the lipid component was supplied by linseed oil (LO). All diets satisfied the nutritional requirements of salmonid fish for n-3 PUFA. There were no statistically significant differences in final weights between dietary treatments in the third trial. However, in the second trial fish fed the intermediate level of linoleic acid (25%) attained a significantly higher final weight compared to both other treatments while fish fed the highest level of linoleic acid (45%) had significantly lower final weights compared to both other treatments. In the first trial the effect of diet on growth (weight gain) could not be ascertained as the initial weights of the fish were significantly different. 3. A number of fish fed SO developed severe cardiac lesions which caused thinning of the ventricular wall and heart muscle necrosis. In addition the fish fed diets containing SO were susceptible to a transportation-induced shock syndrome that resulted in 30% mortality. 4. Incorporation of linoleic acid (18:2n-6) into membrane phospholipids increased in response to dietary intake with fish fed SO having increased levels of 18:2n-6 (up to 15-fold), 20:2n-6 (up to 12-fold), 20:3n-6 (up to 25-fold) and arachidonic acid (AA; 20:4n-6) (up to 3-fold), and decreased levels of eicosapentaenoic acid (EPA; 20:5n-3) (up to 3-fold). The ratio of n-3/n-6 PUFA was decreased (up to 4-fold) and the20:4n-6/20:5n-3 ratio increased (up to 9-fold) in membrane phospholipids from fish fed SO compared to those fed fish oil. While the tissue phospholipids from fish fed La had increased levels of 18:2n-6, 20:2n-6 and 20:3n-6, the levels of AA, 22:4n-6 and 22:5n-6 were similar to or significantly reduced compared to fish fed FO. Membrane phospholipids from fish fed LO also had increased 18:3n-3 and 20:4n-3 compared to both other treatments while in some tissues and phospholipid classes EPA was increased compared to fish fed FO. 5. These dietary induced changes in phospholipid eicosanoid precursor ratio were reflected in altered eicosanoid production. In gill cells, stimulated with the calcium ionophore A23187, 12-hydroxy-8, 10, 14, 17-eicosapentaenoic acid (12-HEPE) was the major 12-lipoxygenase product in fish fed Fa. In stimulated gill cells from fish fed SO and LO, 12-HEPE, 12-hydroxy-5, 8, 10, 14-eicosatetraenoic acid (12-HETE), 14- hydroxy-4, 7, 10, 13, 16, 19-docosahexaenoic acid (14-HDHE) and thromboxane B2 (TXB2) were all decreased compared to fish fed FO. However, the ratio of 12- HETE/12-HEPE was significantly elevated in stimulated gill cells from SO-fed fish compared to both other treatments. In stimulated blood leucocytes leukotriene B4 (LTB4)' 12-HETE and TXB2 were significantly increased while LTB5 and 12-HEPE were significantly decreased in fish fed SO compared to those fed FO. Blood leucocytes from fish fed LO produced less TXB2 compared to fish fed SO and prostaglandin E2 was reduced compared to both other treatments. In isolated cardiac myocytes stimulated with A23187, TXB2 production was increased in SO fed fish compared to those fed FO. 6. The activity of cardiac sarcoplasmic reticulum Ca2+-Mg2+ATPase was not affected by dietary treatment. 7. An established cell line derived from chum salmon heart (CHH-1) was utilised to study PUFA metabolism. The CHH-1 cells exhibited considerable A6 desaturase activity but showed no preference towards n-3 over n-6 PUFA. CHH-1 cells did exhibit significant A5 desaturase activity which showed a preference towards n-3 PUFA. No A4 desaturation activity was observed. Elongation of C20 PUFA was especially active in CHH-1 cells with C22 PUFA being specifically incorporated into phosphatidylethanolamine (PE) and phosphatidylserine (PS). CHH-1 cells supplemented with 20:3n-6 showed reduced growth rate, cell death and unusual pycnotic appearance, compared to those supplemented with other PUFA. 8. The lipid compositions of hearts and livers from wild and farmed parr and presmolts were analysed and compared. The fatty acid compositions of triacylglycerols (TAG) and phospholipids from both farmed parr and pre-smolts contained greater amounts of monoenoic fatty acids compared to their wild counterparts. TAG, phosphatidylcholine (PC) and PE from heart and liver of wild fish contained more 18:2n-6 and AA compared to farmed fish. Linolenic acid, EPA and 22:Sn-3 were increased in hearts and livers of wild fish compared to farmed. Docosahexaenoic acid (DHA; 22:6n-3) levels were higher in heart and liver of farmed fish, particularly in heart PC, PS and TAG. The n-3/n-6 PUFA ratio was generally lower in wild compared to farmed fish, largely due to higher n-6 PUFA, in particular AA, in wild fish. 9. The results are discussed with respect to the competitive interactions between PUFA of the n-6 and n-3 series which determine the fatty acid compositions of membrane phospholipids in salmon. The ratio of n-3/n-6 PUFA in membrane phospholipids, and in particular the ratio of AAIEPA, appears important in terms of membrane physiology and biochemistry, eicosanoid production and the development of cardiac histopathological lesions.

Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第17522号 / 工博第3681号 / 新制||工||1560(附属図書館) / 30288 / 京都大学大学院工学研究科物質エネルギー化学専攻 / (主査)教授 辻 康之, 教授 大江 浩一, 教授 松原 誠二郎 / 学位規則第4条第1項該当

The design of pile foundations in conventional geotechnical engineering practice is based on the soil mechanics principles for saturated soils. These approaches are also extended to pile foundations that are placed totally or partially above the ground water table (i.e., vadose zone), where the soil is typically in a state of unsaturated condition. Such approaches lead to unrealistic estimations of the load carrying capacity and the settlement behavior of pile foundations. Some studies were undertaken in recent years to understand the influence of the matric suction towards the bearing capacity of model pile foundations placed in unsaturated fine-grained and coarse-grained soils. The conventional   and methods were modified to interpret the contribution of shaft carrying capacity of single piles in fine-grained soils (e.g., Vanapalli and Taylan 2011, Vanapalli and Taylan 2012). Also, the conventional method has been used to understand the contribution of matric suction towards the shaft resistance in unsaturated sands (Vanapalli et al. 2010). One of the key objectives of the present research study is directed to determine the contribution of matric suction towards the bearing capacity and settlement behavior of model single pile foundations in unsaturated sands. A series of single model pile load tests were performed in a laboratory environment to study the contribution of the matric suction towards the total, shaft, and base bearing capacity of the model piles with three different diameters (i.e., 38.30, 31.75, and 19.25 mm) in two unsaturated sands (i.e., a clean commercial sand and a super fine sand). Hanging column method (i.e., plexi glass water container) was used to control the matric suction values in the compacted sands in the test tank by varying the water table. The results of the testing programs indicate the significant contribution of the matric suction towards the bearing capacity of single model piles (i.e., 2 to 2.5 times of base bearing capacity and 5 times of shaft bearing capacity under unsaturated conditions in comparison with saturated condition). The test results were interpreted successfully by modifying the conventional methods for estimating the pile shaft bearing capacity (i.e., β method) and base bearing capacity (i.e., Terzaghi 1943, Hansen 1970 and Janbu 1976). In addition, semi-empirical methods were proposed for predicting the bearing capacity of single model piles using the effective shear strength parameters (i.e., c' and ϕ') and the soil-water characteristic curve (SWCC). There is a good agreement between the measured and the predicted bearing capacity of single model piles using the semi-empirical models proposed in this study. In addition, numerical investigations were undertaken using the commercial finite element analysis program SIGMA/W (Geostudio 2007) to simulate the load-displacement (i.e., p-δ) behavior of the single model piles for the two sands (i.e., clean commercial sand and super fine sand) under saturated and unsaturated conditions. An elastic-perfectly plastic Mohr-Coulomb model that takes into account the influence of the matric suction was used to simulate the load-displacement (i.e., p-δ) behavior. The numerical approach proposed in this thesis is simple and only requires the information of the effective shear strength parameters (i.e., c' and ϕ'), the elastic modulus (i.e., Esat) under saturated conditions, the soil-water characteristic curve (SWCC), and the distribution of the matric suction with respect to depth. The approaches proposed in this thesis can be extended to determine the in-situ load carrying capacity of single piles and also simulate the load-displacement (i.e., p-δ) behavior. The studies presented in this thesis are promising and encouraging to study their validity in-situ conditions. Such studies will be valuable to implement the mechanics of unsaturated soils into geotechnical engineering practice.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22472号 / 工博第4733号 / 新制||工||1739(附属図書館) / 京都大学大学院工学研究科合成・生物化学専攻 / (主査)教授 梅田 眞郷, 教授 浜地 格, 教授 跡見 晴幸 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

Ce travail a pour objectif d’étudier la fissuration des sols due au séchage par des approches numérique et analytique. L’initiation et la propagation des fissures sont investiguées en utilisant un code de calcul aux éléments finis avec la présence des joints cohésifs. Les couplages entre le problème hydraulique et le comportement mécanique en présence des discontinuités sont considérés. La loi de la fissure cohésive est appliquée pour modéliser l’initiation et la propagation des fissures.Tout d’abord, les résultats d’un essai de séchage au laboratoire réalisé sur un sol argileux à l’état liquide sont utilisés afin d’évaluer la méthode numérique proposée. Les résultats numériques montrent que le modèle est capable de reproduire les tendances principales du processus de séchage. Elle souligne aussi l’importance des conditions aux limites dans l’initiation des fissures. Ensuite, une approche énergétique est proposée pour étudier l’initiation d’une fissure. Les énergies élastiques avant et après l’initiation de la fissure sont estimées par les deux approches analytique et numérique. L’énergie dissipée lors de l’initiation de la fissure est comparée avec le taux d’énergie pour créer une fissure. Les analyses montrent que le critère d’énergie peut est atteint avant le critère de contrainte. La dissipation de l’énergie cumulée correspond à la propagation instable lors de l’initiation de la fissure. De plus, le développement et la géométrie des fissures sont étudiés essentiellement par les simulations numériques avec plusieurs joints cohésifs. Les résultats numériques montrent que la fissuration se produit souvent progressivement pour former différentes familles de fissures par un processus dichotomique (une fissure apparait au milieu de deux fissures existantes). La propagation d’une fissure est brutale dans la phase d’initiation pour atteindre une profondeur appelée ‘ultime’. Les fissures dans chaque famille peuvent apparaitre simultanément à un même niveau de succion et présentent une même profondeur ultime. En se basant sur les résultats numériques et quelques analyses analytiques supplémentaires, des relations empiriques sont proposées afin de prédire l’espacement et la profondeur ultime des fissures. Finalement, quelques calculs préliminaires sont réalisés afin d’évaluer le potentiel de la méthode numérique proposée pour prédire la fissuration liée au séchage des ouvrages en terre / This work focuses on the analysis of desiccation cracking by numerical and analytical approaches. The initiation and the propagation of cracks are investigated by using a finite element code including cohesive joints elements. Coupling between the hydraulic and the mechanical processes in the presence of discontinuities is considered. The cohesive crack’s law is applied to simulate the initiation and the propagation of cracks.Results of a laboratory experiments performed on slurry clay soil are first used to evaluate the proposed numerical modelling method. The results show that the method is able to reproduce the main trends of desiccation process. The importance of boundary conditions are also discussed. Second, an energy approach is proposed to study the initiation of cracks. The energies before and after crack initiation are estimated by both numerical and analytical solutions. The energy released by cracking is then compared to the crack energy to discuss crack initiation conditions. The analysis shows that the energy criterion is reached before the stress criterion, and this can explain unstable crack propagation at the beginning. Third, the development and the geometry of desiccation cracks are studied by numerical simulation with several cohesive joints. The numerical results show that cracking occurs sequentially to form different cracks families with a dichotomy process (the subsequent cracks appear at the middle of two existing neighboring ones). The cracks in each family appear simultaneously and reach an identical ultimate depth. From the numerical results and additional analytical analysis, empirical correlations are proposed to predict the spacing and crack depth. Finally, some preliminary studies are performed showing that the proposed numerical method can be used to predict the desiccation crack phenomena observed on geotechnical earth structures