The objective of this study is to characterize the long-term behavior of an austenitic-ferritic stainless steel-based pretensioned system for strengthening reinforced concrete bridge pier caps in shear. Stress relaxation experiments were conducted on UNS S32101 stainless steel bars subjected to various initial stresses and temperatures within the low homologous temperature (LHT) regime. Data from these experiments were used to develop a viscoplastic constitutive model to describe the long-term time- and temperature-dependent behavior of the stainless steel bars. This mechanics-based approach is integrated with an analytical method based on strut-and-tie analysis to compute the shear strength of reinforced concrete pier caps strengthened with this external pretensioned system.

Doctor of Philosophy / Department of Agronomy / P. V. Vara Prasad / High temperature is a major environmental factor that limits wheat productivity. Climate models predict greater increases in night temperature than in day temperature. The objectives of this research were to quantify the effects of high day and night temperatures during anthesis on physiological (chlorophyll fluorescence, chlorophyll concentration, leaf level photosynthesis, lipid peroxidation and membrane damage), biochemical (reactive oxygen species [ROS] concentration and antioxidant capacity in leaves) and yield traits and membrane lipid profile and identify the lipids that are associated with high temperature response in wheat. Winter wheat genotypes Ventnor (heat tolerant) and Karl 92 (heat susceptible) were grown at optimum temperatures (25/15°C, maximum/minimum) until the onset of anthesis. Thereafter, plants were exposed to high night (HN, 25/24°C), high day (HD, 35/15°C), high day and night (HDN, 35/24°C) or optimum temperatures. Compared with optimum temperature, HN, HD and HDN increased ROS concentration, lipid peroxidation and membrane damage and decreased antioxidant capacity, photochemical efficiency, photosynthesis, seed set, grain number and grain yield. Impact of HN and HD was similar on all traits, when stress was imposed for seven days. High day and night temperatures resulted in significant changes in the amount of plastidic and extra-plastidic lipids and lipids with oxidized acyl chains (ox-lipids) in both genotypes. The decrease in lipid unsaturation levels of complex lipids at high temperatures was predominantly due to decrease in 18:3 fatty acid and increase in 18:1 and 16:0 fatty acids. We identified novel odd-numbered long-chain fatty acid-containing phospholipids, which were highly responsive to high temperature stress. Ventnor had higher amounts of sterol glycosides (SG) and lower amounts of ox-lipids at high temperatures than Karl 92; thus SGs and ox-lipids may be potential biomarkers for heat tolerance and susceptibility, respectively, in wheat. Co-occurring lipids, which are up-or-down-regulated together through time under high day and night temperatures formed groups, which were experiencing coordinated metabolism. These results suggest that high day and night temperatures during anthesis cause damage of a similar magnitude to wheat, if stress is imposed for a short term (seven days) and compositional changes in lipid profile in response to high temperature contribute to heat tolerance.

京都大学 / 新制・論文博士 / 博士(農学) / 乙第13423号 / 論農博第2898号 / 新制||農||1086(附属図書館) / 学位論文||R3||N5346(農学部図書室) / (主査)教授 中嶋 洋, 教授 近藤 直, 教授 飯田 訓久 / 学位規則第4条第2項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

Chlamydomonas priscuii is a psychrophilic green alga found 17 m below the permanently ice-covered surface of the Antarctic Lake Bonney, where it experiences a myriad of extreme environmental conditions, including low temperature, low light, and high salinity. While this habitat is extreme, it is also very stable, and this alga rarely experiences changes in its environment. Heat shock proteins (HSPs) are a ubiquitous family of chaperone proteins that perform important housekeeping and stress-related roles. In most organisms, including the model green alga Chlamydomonas reinhardtii, HSP expression is induced during abiotic stress to regain protein homeostasis – a process regulated by heat shock transcription factors (HSFs). This work shows that C. priscuii constitutively accumulates high protein levels of HSPs in steady-state conditions but fails to induce additional HSP accumulation during heat and low temperature, high and low salt, high light, and with canavanine treatment. In this study, a single HSF was identified in the C. priscuii genome. Comparative sequence analysis revealed that most domains characteristic of a functional HSF are conserved, but the expression of a full length HSF1 transcript could not be detected in the cell. Furthermore, the promoters of many C. priscuii HSPs lack binding sites for HSF. This work has shown that C. priscuii has a diminished ability to regulate HSP expression under stressful conditions, which we hypothesize is a result of life in an extreme but very stable environment. This is the first demonstration of a loss of HSP accumulation in green algae, which carries implications on the ability of psychrophiles to survive in the face of climate change.

京都大学 / 新制・論文博士 / 博士(農学) / 乙第13529号 / 論農博第2910号 / 新制||農||1096(附属図書館) / 学位論文||R5||N5425(農学部図書室) / 京都大学大学院農学研究科農学専攻 / (主査)教授 中﨑 鉄也, 教授 土井 元章, 教授 樋口 浩和 / 学位規則第4条第2項該当 / Doctor of Agricultural Science / Kyoto University / DGAM

The ability to acclimate to changing temperature has consequences for the biogeographic range of a species and their potential for surviving ocean warming. Using a tide simulator, which recreates tidal conditions by controlling water levels, water and air temperatures, light levels, and food availability, we explored how temperature and tidal zone (i.e. intertidal and subtidal) influences the abundance of sirtuin 5 (SIRT5) protein in a California native mussel (Mytilus californianus). We compared how gill tissue abundance of SIRT5, a key regulator of the cellular stress response and energy metabolism responded in M. californianus exposed to different temperature conditions (13, 16, 19 and 22°C) over a period of four weeks. Two SIRT5 isoforms, one a putative cytosolic form and the other a mitochondrial form were found to be expressed in mussel gill tissue. The mitochondrial isoform increased during acclimation to warm temperatures. This finding is the first to show how SIRT5 protein abundance changes with temperature acclimation. Surprisingly, we did not identify any differences in gill SIRT5 abundance between mussels from intertidal and subtidal locations. Our results suggest that characterizing the responses of SIRT isoforms may lead to a better understanding of the physiological diversity of sirtuins.

Doctor of Philosophy / Department of Agronomy / P.V. Vara Prasad / High temperature (HT) and drought are detrimental to crop productivity, but there is limited variability for these traits among wheat ([italics]Triticum aestivum[end italics] L.) cultivars. Five [italics]Aegilops[end italics] species were screened to identify HT (52 accessions) and drought (31 accessions) tolerant species/accessions and ascertaining traits associated with tolerance. Four synthetic wheats were studied to quantify independent and combined effects of HT and drought. [italics]Aegilops[end italics] species were grown at 25/19°C day/night and 18 h photoperiod. At anthesis, HT was imposed by transferring plants to growth chambers set at 36/30°C, whereas in another experiment, drought was imposed by withholding irrigation. Synthetic wheats were grown at 21/15°C day/night and 18 h photoperiod. At anthesis or 21 d after anthesis, plants were exposed to optimum condition (irrigation + 21/15°C), HT (irrigation + 36/30°C), drought (withhold irrigation + 21/15°C), and combined stress (withhold irrigation + 36/30°C). Stresses were imposed for 16 d. High temperature and drought stress significantly decreased chlorophyll, grain number, individual grain weight, and grain yield of [italics]Aegilops[end italics] species (≥ 25%). Based on a decrease in grain yield, [italics]A. speltoides[end italics] and [italics]A. geniculata[end italics] were most tolerant (~ 61% decline), and [italics]A. longissima[end italics] was highly susceptible to HT stress (84% decline). Similarly, [italics]A. geniculata[end italics] had greater tolerance to drought (48% decline) as compared to other species (≥ 73% decline). Tolerance was associated with higher grains spike [superscript]-1 and/or heavier grains. Within [italics]A. speltoides[end italics], accession TA 2348 was most tolerant to HT with 13.5% yield decline and a heat susceptibility index (HSI) 0.23. Among [italics]A. geniculata[end italics], TA 2899 and TA 1819 were moderately tolerant to HT with an HSI 0.80. TA 10437 of [italics]A. geniculata[end italics] was the most drought tolerant accession with 7% yield decline and drought susceptibility index 0.14. Irrespective of the time of stress, HT, drought, and combined stress decreased both individual grain weight and grain yield of synthetic wheats by ≥ 37%, 26%, and 50%, respectively. These studies suggest a presence of genetic variability among [italics]Aegilops[end italics] species that can be utilized in breeding wheat for HT and drought tolerance at anthesis; and combined stress of drought and high temperature on synthetic wheats are hypo-additive in nature.

Made available in DSpace on 2014-06-11T19:27:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2004-02Bitstream added on 2014-06-13T19:15:07Z : No. of bitstreams: 1 falcon_dr_me_botfmvz.pdf: 542401 bytes, checksum: d9c54912cf869db2987b5014cda8a0f2 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Visando o preparo da tilápia do Nilo, Oreochromis niloticus, para o período de inverno, foram avaliados durante 112 dias diferentes níveis de suplementação de lipídeo e vitamina C, no desempenho produtivo e parâmetros fisiológicos. Foi utilizado um lote de 192 alevinos, com peso médio de 5,57 0,50 g distribuídos aleatoriamente em 32 tanques-rede de 200 L cada, dispostos em oito aquários de 1000 L, dotados de sistema de aquecimento e de recirculação de água com filtragem mecânica e biológica. O experimento foi conduzido num esquema fatorial 2 x 3, com dois níveis de lipídeo (8,0 e 12,0%) e três níveis de vitamina C (300,0; 600,0 e 1200,0 mg de vitamina C/kg da dieta), com quatro repetições, mais dois tratamentos, um ausente de suplementação dos nutrientes testes e outro acrescido de 6,0% de lipídeo e 125,0 mg de vitamina C/kg da dieta. Foram confeccionadas oito rações práticas, isoprotéicas com 32,0% de proteína digestível. O suplemento vitamínico e mineral utilizado foi isento de vitamina C, sendo considerada como fonte somente o adicionado à dieta. A vitamina C utilizada foi a polifosfatada com 35,0% de atividade e a fonte de lipídeo o óleo de soja. Os resultados permitiram concluir que a energia adicional proveniente do lipídeo é depositada na cavidade abdominal na forma de gordura visceral; que a deposição desta gordura como reserva de energia para transpor o período de inverno foi obtida em todos os níveis de suplementação de lipídeo, sendo a suplementação com 8,0% a mais adequada; que a concentração hepática de vitamina C é proporcional a concentração desta na dieta porém, em função da capacidade de reserva do fígado a quantidade de 600,0 mg de vitamina C/kg da dieta mostra-se mais apropriada economicamente e que a ausência de vitamina C prejudica a eritropoiese e a síntese de colágeno. / It were evaluated during 112 days different lipid and vitamin C supplementation in practical diets, on growth performance and physiologic parameters of Nile tilapia, aiming the animals preparation for winter time. It was utilized 192 fingerlings, selected from the same spawn, with average weight of 5.57 0.50 g. These were randomly stocked into 32 200-l aquaria, supplied with heat system and recycled water with mechanic and biological filter. The experiment was conducted in factorial design 2 x 3, two levels of lipid (8.0 and 12.0%) and three levels of vitamin C (300.0; 600.0 and 1,200.0 mg of vitamin C/kg diet), with four replicates each treatment, plus two treatments, absence of test nutrients supplementation and supplemented with 6.0% of lipid and 125.0 mg of vitamin C/kg diet. Eight experimental practical diets were formulated to contain 32.0% of digestible protein. Vitamin and mineral mix was absent of vitamin C, considering as a source only the supplemented in diets. The vitamin C utilized was polyphosphate 35.0% activity. Based on the results it was concluded that the additional energy coming from lipid is accumulated in abdominal cavity as visceral fat; fat deposition as a energy reserve for winter time was obtained in all lipid supplementation, however 8.0% supplementation seems to be more appropriate; vitamin C liver concentration is proportional to diet concentration, but because of liver reserve capacity the amount of 600.0 mg of vitamin C/kg diet appears to be more economic appropriate and that vitamin C absence impairment erythropoiesis and collagen syntheses.

Submitted by MARÍLIA GABRIELA DE SANTANA COSTA null (mariliagabrielasc@hotmail.com) on 2017-06-01T19:21:17Z No. of bitstreams: 1 TESE_MARILIA_GABRIELA_SANTANA_COSTA.pdf: 4170522 bytes, checksum: 8ff9e42b797cdb58ebfce7e345bfe167 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-06-02T13:34:14Z (GMT) No. of bitstreams: 1 costa_mgs_dr_jabo.pdf: 4170522 bytes, checksum: 8ff9e42b797cdb58ebfce7e345bfe167 (MD5) / Made available in DSpace on 2017-06-02T13:34:14Z (GMT). No. of bitstreams: 1 costa_mgs_dr_jabo.pdf: 4170522 bytes, checksum: 8ff9e42b797cdb58ebfce7e345bfe167 (MD5) Previous issue date: 2017-04-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A indústria de papel e celulose brasileira ocupa uma posição de destaque no mercado mundial. O Eucalyptus grandis é a espécie mais plantada pelo setor florestal e a principal fonte de matéria-prima para a indústria de papel e celulose. Contudo, seu crescimento em regiões de baixa temperatura é limitado. Contrariamente, a espécie Eucalyptus globulus apresenta melhor crescimento em baixas temperaturas, tornando-se cada vez mais interessante para a indústria nacional de papel e celulose. Tendo em vista que a temperatura é um modulador chave no metabolismo das plantas, uma análise global do proteoma foi realizada em plântulas cultivadas em temperaturas controladas, visando a identificação de proteínas diferencialmente reguladas entre as espécies e entre as diferentes condições de cultivo, detecção de vias metabólicas estimuladas pela temperatura e detecção de alterações no metabolismo antioxidante e de lignificação. A estratégia adotada permitiu a identificação de 3.111 proteínas caulinares, representando aproximadamente 9% do proteoma predito para a espécie modelo E. grandis. O perfil de expressão gênica, em termos de número de proteínas identificadas, corroborou com o padrão de densidade gênica para os cromossomos de Eucalyptus. Foram identificadas proteínas envolvidas em diversas vias metabólicas, com destaque para as vias relacionadas com o metabolismo energético, de aminoácidos e nucleotídeos, de lipídeos e carboidratos. Com relação às proteínas diferencialmente reguladas, 16 proteínas apresentaram alteração em sua abundância somente em E. grandis, 38 somente em E. globulus e 12 apresentaram alterações em ambas as espécies. Além disso, um total de 103 proteínas antioxidantes foram detectadas nos caules de ambas as espécies. O perfil de regulação frente ao estímulo térmico, revelou que as alterações nas proteínas antioxidantes são mais proeminentes quando as mudas de Eucalyptus foram expostas a altas temperaturas. Com relação à biossíntese de lignina, a nossa abordagem proteômica resultou na identificação de 27 das principais enzimas envolvidas neste metabolismo, corroborando com as predições de genes e o “toolbox” de lignificação proposto. A análise quantitativa revelou diferenças na abundância de isoformas específicas dependendo do estímulo térmico em que as plantas foram expostas; contudo, o tratamento a alta temperatura foi aquele que induziu mais diferenças entre os proteomas relacionados com a lignificação de E. globulus e de E. grandis. A partir dos resultados obtidos, conclui-se que o estímulo térmico promove alterações importantes no proteoma caulinar jovem de Eucalyptus, evidenciando aumento na atividade antioxidante em plantas expostas ao calor e expressão diferencial mais proeminente em plantas submetida ao frio. / The Brazilian pulp and paper industry occupies a prominent position in the world market. The Eucalyptus grandis is the most used species in the forest sector and the main source of raw material for Brazilian industry. However, its growth in low temperature regions is limited. In contrast, the Eucalyptus globulus species shows a better growth at low temperatures, for whom interest has increased within the national pulp and paper industry. Since temperature is a key modulator in plant metabolism, a global proteome analysis was performed on seedlings grown at controlled temperatures, aimed at the identification of differentially regulated proteins between the species and between the different culture conditions, detection of metabolic pathways stimulated by temperature and detection of alterations in antioxidant metabolism and lignification. The strategy used here allowed the identification of 3,111 stem proteins, representing approximately 9% of the predicted proteome of the E. grandis model species. The gene expression profile, in terms of the number of proteins identified, corroborated with the gene density pattern for the Eucalyptus chromosomes. Proteins involved in several metabolic pathways have been identified, especially the pathways related to energy metabolism, and metabolism of amino acids, nucleotides, lipids and carbohydrates. Regarding the differentially regulated proteins, 16 proteins showed alterations in their abundance only in E. grandis, 38 only in E. globulus and 12 presented alterations in both species. In addition, a total of 103 antioxidant proteins were detected in the stems of both species. The regulation profile upon thermal stimulus revealed that changes in antioxidant proteins are more prominent when Eucalyptus seedlings were exposed to high temperatures. Regarding the biosynthesis of lignin, our proteomic approach resulted in the identification of 27 of the main enzymes involved in this metabolism, corroborating with the gene predictions and the proposed lignin toolbox. Quantitative analysis revealed differences in the abundance of specific isoforms depending on the thermal stimulus to which the plants were exposed; however, the high temperature treatment was the one that induced more differences between the proteomes related to the lignification of E. globulus and E. grandis. The results demonstrate that thermal stimuli cause important alterations in the Eucalyptus stem proteome, evidenced by the increase in the antioxidant activity in plants exposed to heat and the most prominent differential expression in plants submitted to cold environments.

Made available in DSpace on 2016-01-26T18:56:34Z (GMT). No. of bitstreams: 1 Dissertacao Marcia.pdf: 237755 bytes, checksum: cc3f62f324b3824c463dbc43ad5d87b2 (MD5) Previous issue date: 2007-10-19 / Stress could be defined as an external factor that could cause some disadvantageous influence over the plant. In tropical regions, crops suffer non biotic stress especially due to water deficit and high temperature. Cross tolerance allow the plants to be acclimated after a short exposition to a specific stress. The objective of this work was to verify the water stress tolerance during bean seed germination influenced by thermal shock induced cross tolerance. Seed of common bean cv IAPAR 81 were submitted to the imbibition in substrate paper with pure water at 20ºC for 24h. One third of the seeds were maintained in that temperature. One third were submitted to cold shock for 24h at 7ºC in the first assay and 13ºC in the second and the final part were submitted to heat shock for 24h at 38ºC and 33ºC as used for the cold shocks; in all experiments there was no change of substrate. Seeds submitted or not to shock were transferred to paper substrate simulating hydric potential of 0; -0.6; -0,9 and -1.2MPa, in the first experiment and 0;-0.3; -0.6; -0.9 and -1.2MPa in the second experiment using mannitol at: 0; 22.29; 44.58; 66.87 e 89.17 g.L-1. Treatments were evaluated by germination percentage, abnormal plants and dead seeds. Seedling evaluation was done with shoot, root and total dry matter and by relation of root/shoot. The best development, in water restriction in the early germination, was of that seeds that passed through a 7ºC or 33ºC during 24h, what allowed the affirmation that induced cross tolerance occurred and that could be induced in the beginning of the imbibition in bean seeds. / Estresse pode ser definido como um fator externo, que exerce influência desvantajosa sobre a planta. Em regiões tropicais, as culturas agrícolas sofrem estresse abiótico principalmente por períodos de deficiência de água e excesso de temperatura. A tolerância cruzada permite às plantas se aclimatarem a uma gama de diferentes estresses após exposição a um estresse específico. O objetivo deste trabalho foi avaliar a tolerância ao estresse hídrico durante a germinação das sementes de feijão sob influência da tolerância cruzada induzida por choque térmico. As sementes de feijão cultivar IAPAR 81 foram submetidas ao processo de embebição, em substrato papel-toalha umedecido com água pura sob temperatura de 20ºC por 24 horas. A seguir, parte foi mantida nessa temperatura e parte transferida para o choque frio por 24 horas a 7ºC no ensaio 1 e 13ºC no ensaio 2 e outra parte para o choque quente por 24 horas a 38oC no ensaio 1 e 33oC no ensaio 2, sem troca do substrato. Tanto as sementes que passaram pelo choque como as que não passaram (controle) foram transferidas para substrato papel simulando diferentes potenciais hídricos, 0; -0,6; -0,9 e -1,2MPa, no ensaio 1 e 0;-0,3; -0,6; -0,9 e 1,2MPa no ensaio 2, induzidos por manitol nas seguintes concentrações: 0; 22,29; 44,58; 66,87 e 89,17 g.L-1. Os tratamentos foram avaliados por meio da porcentagem de germinação, plântulas anormais e sementes mortas; avaliações do desenvolvimento como massa seca da parte aérea, massa seca de raiz, massa seca total e relação raiz/parte aérea. O melhor desempenho das sementes que passaram por choque, de 7oC por 24h ou de 33oC por 24h, à restrição hídrica no início do desenvolvimento, permite afirmar que ocorreu indução de tolerância cruzada e que esta pode ser induzida no início do processo de embebição em sementes de feijão.