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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
431

Síntese e atividade biológica de dissacarídeos acoplados a aminoácidos / Synthesis and biological activity of disaccharides attached to amino acids.

Andrade, Peterson de 09 April 2008 (has links)
trans-Sialidase de Trypanosoma cruzi (TcTS) pertence à família de glicoproteínas de superfície do parasita e constitui um dos poucos exemplos naturais de glicosiltransferases superficiais encontradas em eucariotes. T. cruzi é incapaz de sintetizar ácido siálico e utiliza esta enzima para retirar este monossacarídeo de glicoconjugados do hospedeiro para sialilar moléculas aceptoras, como mucina-GPI (glicosilfosfatidilinositol), presentes na sua membrana plasmática. Esta enzima é específica em catalisar, preferencialmente, a transferência de ácido siálico para moléculas de mucina, originando ligações -2,3 com moléculas de galactose aceptoras na superfície do parasita. Considerando a heterogeneidade das moléculas de mucina de T. cruzi, é necessário que novas moléculas sejam sintetizadas a fim de que estas atuem como substratos glicopeptídicos, os quais podem levar ao melhor entendimento das interações entre enzima e substratos e permitir o planejamento racional de inibidores seletivos. Por isso, o trabalho foi divido em três rotas sintéticas: (i) preparação do doador de galactose, (ii) preparação dos aceptores-doadores e (iii) acoplamento dos dissacarídeos com aminoácidos aceptores para obtenção dos blocos de construção. Apesar dos objetivos propostos inicialmente não terem sido totalmente alcançados, o trabalho desenvolvido durante esse período permitiu a síntese do doador de galactose (3) em três etapas, aceptor de galactose (6) em cinco etapas, dissacarídeo (11) na glicosilação de 6 com 3, aminoácidos aceptores (13 e 14) e também dos blocos de construção (17 e 18) decorrente do acoplamento de 11 com os aminoácidos aceptores. Não obstante, é importante ressaltar que apesar da extensa rota planejada, porém necessária, a síntese dos blocos de construção é inédita. Portanto, pode-se concluir que o trabalho trouxe relevante contribuição no que diz respeito à química de carboidratos e à disponibilização de dados espectrométricos de compostos orgânicos para a literatura. / Trypanosoma cruzi trans-sialidase (TcTS) belongs to the family of glycoproteins expressed on the surface of the parasite and constitutes one of the few examples of natural surface glycosyltransferases found in eucariotes. T. cruzi can not synthesize sialic acid itself and uses this enzyme to scavenge this monosaccharide from host glycoconjugates to sialylate acceptors molecules, such as GPI (glycosylphosphatidylinositol) mucins, that are present in parasite plasma membrane. This enzyme is specific to catalyze, preferentially, the transference of sialic acid to mucin glycoproteins, generating -2,3-linkages with acceptor galactose molecules in the parasite surface. Considering the heterogeneity of T. cruzi mucin molecules, its necessary to synthesize new compounds that can act as glycopeptide substrates, leading to a better understanding concerning the enzyme and substrates and allow the rational design of some selective inhibitors. Thus, this work was developed in three synthetic routes: (i) the synthesis of galactose donor, (ii) synthesis of donor-acceptors and (iii) coupling between disaccharides and acceptors amino acids in order to obtain building blocks. Despite of some objectives initially proposed had not been accomplished, the developed work during this period allow the synthesis of the galactose donor (3) in three steps, donor-acceptor (6) in five steps, disaccharide (11), acceptors amino acids (13 and 14) and also the building blocks (17 and 18). However, its important highlight that the synthesis of the building blocks by this necessary, but extensive, synthetic route is unpublished. Therefore, it can be concluded that the present work brought rich contribution concerning the carbohydrate chemistry and the availability of spectrometric data of organic compounds to the literature.
432

Estudo do metabolismo de propionato em Pseudomonas sp. LFM046 para o controle na composição de polihidroxialcanoatos produzidos / Study of propionate metabolism in Pseudomonas sp. LFM046 to control the composition of polyhydroxyalkanoates produced.

Machado, Nathália Fernandes Gonçalves 29 May 2013 (has links)
Polihidroxialcanoatos (PHA) produzidos por Pseudomonas sp. LFM046 a partir de carboidratos e ácido propiônico contem monômeros com número ímpar e par de carbonos, representando um bom modelo para o estudo do metabolismo de propionato. Genes relacionados ao ciclo do 2-metilcitrato foram encontrados em todas as espécies de Pseudomonas compondo um operon prpRBCAcnMprpFD. Genes da via do metilmalonil-CoA não foram encontrados em Pseudomonas. Genes da <font face=\"Symbol\">a-oxidação de propionato foram encontrados apenas em P. aeruginosa. A análise de um mutante prp obtido por inserção de transposon revelou que estava mutado no gene prpB, relacionado ao ciclo do 2-metilcitrato. A análise de mutantes obtidos por radiação ultravioleta revelou que dois devem estar afetados em via menos relevante para o metabolismo de propionato e outros dois na ativação desse ácido orgânico. Experimentos com propionato marcado (1C13) demonstraram que as vias do oxobutirato, do metimalonil-CoA e do 2-hidroxiglutarato não devem contribuir para o metabolismo de propionato em Pseudomonas sp. LFM046. / Polyhydroxyalkanoates (PHA) produced by Pseudomonas sp. LFM046 from carbohydrates and propionic acid contains monomers with odd and even number of carbons, representing a good model to study the propionate metabolism. Genes related to 2-methycytrate cycle were found in all Pseudomonas species organized in an operon prpRCAAcnMprpFD. Genes related to the methylmalonyl-CoA pathway were not found in Pseudomonas. Genes related to the propionic <font face=\"Symbol\">a-oxidation were found only in P. aeruginosa. Analysis of a prp mutant obtained by transposon insertion revealead that it was mutated in prpB gene, related to the 2-methylcytrate cycle. The analysis of mutants obtained using ultraviolet radiation showed that two should be affected in less relevant propionate metabolism pathways and other two in the activation of this organic acid. Experiments with labeled propionate (113C) demonstrated that the oxobutyrate, methylmalonil-CoA and 2-hydroxyglutarate pathways should not contribute to the propionate metabolism in Pseudomonas sp. LFM046.
433

Variações na composição qualitativa e quantitativa de carboidratos solúveis em plantas de Lolium multiflorum ssp. italicum var. Lema sob a influência de poluentes aéreos na cidade de São Paulo, SP / Qualitative and quantitative variations in the composition of soluble carbohydrates in plants of Lolium multiflorum ssp. italicum var. Lema exposed to urban air pollution

Sandrin, Carla Zuliani 24 August 2007 (has links)
O crescimento das atividades urbano-industriais tem provocado um significativo aumento nas emissões de poluentes aéreos para a atmosfera. A poluição do ar, um dos principais fatores determinantes da destruição do meio ambiente, causa estresse às plantas, já que apresenta compostos altamente reativos e danosos, como os metais pesados. O uso de plantas bioindicadoras de poluição aérea é uma prática comum para o monitoramento da qualidade do ar e para o diagnóstico dos efeitos da poluição aérea na vegetação. Entre as plantas bioindicadoras mais utilizadas, destaca-se a gramínea C3 de clima temperado Lolium multiflorum ssp. italicum Beck var. Lema, que acumula metais pesados, fluoretos e enxofre quando se desenvolve na presença desses elementos químicos no ar. Além disso, esta espécie acumula frutano, um carboidrato solúvel cuja produção pode ser alterada por um número variado de perturbações ambientais. O presente trabalho foi dividido em três experimentos com os objetivos de (1) verificar a partição de carboidratos solúveis em cinco partes distintas (lâmina em alongamento, lâmina expandida, porção superior do estolho, porção inferior do estolho e raízes) de plantas de L. multiflorum; (2) analisar as relações sazonais e diurnas entre concentrações de poluentes aéreos urbanos, principalmente de dióxidos de enxofre e de nitrogênio e de material particulado, entre outros fatores ambientais, concentrações foliares de metais e mudanças no acúmulo de frutanos em plantas de Lolium multiflorum Lam ssp. italicum expostas a diferentes condições de poluição do ar na cidade de São Paulo; (3) verificar se as variações sazonais e diurnas no conteúdo de frutanos são determinadas por acúmulos foliares de enxofre e metais pesados ou por variações nas concentrações de poluentes gasosos; e (4) verificar a eficiência bioacumuladora da variedade “Lema" de Lolium multiflorum para a região tropical. Para isso, as plantas foram expostas durante períodos consecutivos de 28 dias ou 2 meses, em cada estação do ano, em Congonhas (local com altos níveis de poluentes aéreos) e em casa de vegetação com ar filtrado (local controle). Após cada exposição, a frutose total foi quantificada pelo método de antrona e os frutanos analisados qualitativamente por HPAEC-PAD. As concentrações de enxofre foram determinadas por turbidimetria, enquanto que as concentrações de metais pesados (Al, Fe, Cu, Zn, Pb, Cd e Ba) foram medidas utilizando um espectrofotômetro de absorção atômica, após digestão ácida. Os resultados mostraram que o estolho contendo as bainhas foliares de L. multiflorum acumulou mais frutanos, enquanto que as raízes acumularam os menores níveis desse carboidrato. As variações sazonais no conteúdo dos carboidratos solúveis foram marcantes no presente trabalho e pareceram estar relacionadas com as condições climáticas, mas intensificadas pelas concentrações de poluentes aéreos, especialmente de metais pesados contidos no material particulado, e acumulados nas folhas de L. multiflorum expostas em Congonhas. Já as variações diurnas foram sutis, mas suficientes para refletir as variações de irradiância, temperatura e de alguns poluentes gasosos ao longo do dia. Tanto no experimento sazonal como no diurno, os frutanos de alto peso molecular pareceram ter sido hidrolisados sendo o acúmulo de frutanos de peso molecular intermediário preferencial nas plantas dos dois locais de estudo. As interferências no conteúdo e na composição de frutanos influenciaram a produção de biomassa e a partição desta entre as partes da plantas, o que ode ter alterado a capacidade acumuladora da espécie de elementos provenientes da poluição atmosférica. Assim, o uso da variedade Lema de L. multiflorum para fins de biomonitoramento da qualidade do ar em regiões tropicais deve ser cuidadoso. / The development of urban and industrial activities has caused a significant increase in the emissions of pollutants to the atmosphere. Air pollution, one of the most destructive factors of the environment, causes stress to plants, since certain compounds such as heavy metals are very reactive and dangerous to plant cells. The utilization of bioindicator plants is an usual practice to monitor the air quality and to diagnose the effects of air pollution on vegetation. The C3 temperate grass Lolium multiflorum ssp. italicum Beck var. Lema is usually employed as bioindicator of air pollution, due to its high capacity of accumulating heavy metals, fluorine and sulfur when growing in the presence of these chemical elements in the air. This species also accumulates fructan, a soluble carbohydrate, whose production can be altered by to many environmental perturbations. In the present work three experiments were performed aiming (1) to verify the partitioning of water total carbohydrates in five different parts of plants of L. multiflorum (upper stubble; under stubble; elongating leaf, expanded leaf and roots); (2) to analyze the seasonal and the diurnal relationships between the concentrations of urban air pollutants, mainly nitrogen and sulfur dioxides and particulate material, among other environmental factors, leaf concentrations of heavy metals and changes in fructan accumulation in plants of L. multiflorum exposed to different conditions of air pollution in São Paulo city; (3) to verify if the seasonal and diurnal variations in the content of fructans are determined by leaf accumulation of sulfur and heavy metals or by variations in the concentrations of gaseous pollutants or other environmental factors; and (4) to verify the bioindicator efficiency of the variety “Lema" of Lolium multiflorum in tropical areas. Plants were consecutively exposed during 28 days or two months in each season at Congonhas (site reached by high levels of air pollutants) and at a glasshouse with filtered air (reference situation). After each exposure, fructan composition as well as leaf concentrations of total fructose and of sulfur and metals (Al, Fe, Cu, Zn, Pb, Cd and Ba) were measured. Total fructose was quantified by the anthrone method and fructan composition was analyzed by HPAEC-PAD. Sulfur concentrations were determined by the turbidimetric method, whereas metal concentrations were measured using an atomic absorption spectrophotometer, after acidic digestion. Results showed that the stubble containing the leaf sheaths of L. multiflorum accumulated the highest levels of fructans, while the roots accumulated the lowest levels. Seasonal variations in the contents of soluble carbohydrates were evident in the present work and seemed to be related with the climatic conditions but intensified by the air pollutants, especially heavy metals contained in the particulate matter, and accumulated in the leaves of L. multiflorum exposed in Congonhas. However the diurnal variations were tenuous, but reflected the variations of irradiance, temperature and of some gaseous pollutants during daytime. In the both seasonal and diurnal experiments, the fructans of high molecular weight seemed to be hydrolyzed and the accumulation of fructans of intermediary molecular weigh was significant in the plants from both sites. The changes in the content and in the composition of fructans altered the biomass production and partition among roots and shoots, which might have been disturbed their characteristic of accumulating chemical elements from air pollution in the leaves. So, the use of the variety Lema of L. multiflorum for biomonitoring purposes in tropical areas should be carefully evaluated.
434

Effect of high and low glycemic index meals on short-term recovery from prolonged, submaximal running and subsequent endurance capacity =: 運動後高、低血糖指數食物對短期恢復及再運動時耐力之影響. / 運動後高、低血糖指數食物對短期恢復及再運動時耐力之影響 / Effect of high and low glycemic index meals on short-term recovery from prolonged, submaximal running and subsequent endurance capacity =: Yun dong hou gao, di xue tang zhi shu shi wu dui duan qi hui fu ji zai yun dong shi nai li zhi ying xiang. / Yun dong hou gao, di xue tang zhi shu shi wu dui duan qi hui fu ji zai yun dong shi nai li zhi ying xiang

January 2000 (has links)
Fung Man-yi, Wendy. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 84-106). / Text in English; abstracts and appendices in English and Chinese. / Fung Man-yi, Wendy. / Acknowledgments --- p.i / Presentation --- p.iii / Abstract --- p.iv / Table of Contents --- p.viii / List of Tables --- p.x / List of Figures --- p.xi / Chapter CHAPTER ONE --- Introduction --- p.1 / Research Background --- p.1 / Purpose of the Study --- p.5 / Justification of the Study --- p.6 / Hypotheses --- p.6 / Definition of Terms --- p.7 / Assumptions --- p.8 / Delimitations --- p.8 / Limitations --- p.9 / Significance of the Study --- p.9 / Chapter CHAPTER TWO --- Review of Literature --- p.10 / "Engergy Metabolism During Prolonged, Submaximal Exercise" --- p.10 / "Causes of Fatigue During Prolonged, Submaximal Exercise" --- p.16 / Factors Influencing Muscle Glycogen Resynthesis During Recovery --- p.21 / Factors Influencing Rehydration During Recovery --- p.27 / Effect of Muscle Glycogen Replenishment During Recovery on Subsequent Endurance Capacity --- p.30 / Effect of Rehydration During Recovery on Subsequent Endurance Capacity --- p.32 / Effect of Glycemic Index Meals Before Exercise on Exercise Performance --- p.33 / Chapter CHAPTER THREE --- Methodology --- p.37 / Participants --- p.37 / Equipment and Instrumentation --- p.37 / Standardized Experimental Procedures --- p.38 / Collection and Analysis of Blood Samples --- p.42 / Preliminary Measurements --- p.45 / Dietary Analyses and Training Control --- p.50 / Preliminary Testing --- p.51 / Statistical Analysis --- p.54 / Chapter CHAPTER FOUR --- Results --- p.56 / Run Time to Exhaustion --- p.56 / Dietary Analysis --- p.57 / Postprandial Responses of the Test Meals During Screening Session --- p.58 / Postprandial Responses During Recovery --- p.60 / Responses During Exercise and Recovery --- p.62 / Body Mass Changes and Fluid Balance --- p.74 / Changes in Plasma Volume and Urine Volume --- p.75 / Summary of the Results --- p.76 / Chapter CHAPTER FIVE --- Discussion --- p.77 / Recommendations and Applications --- p.83 / References --- p.84 / Appendixes --- p.107
435

Effect of frequency of high glycemic index foods consumption on short-term recovery from prolonged exercise and subsequent endurance capacity =: 運動後進食高糖份指數食物的次數對短期恢復及再運動時耐力之影響. / 運動後進食高糖份指數食物的次數對短期恢復及再運動時耐力之影響 / Effect of frequency of high glycemic index foods consumption on short-term recovery from prolonged exercise and subsequent endurance capacity =: Yun dong hou jin shi gao tang fen zhi shu shi wu de ci shu dui duan qi hui fu ji zai yun dong shi nai li zhi ying xiang. / Yun dong hou jin shi gao tang fen zhi shu shi wu de ci shu dui duan qi hui fu ji zai yun dong shi nai li zhi ying xiang

January 2001 (has links)
Siu Ming Fai Parco. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 101-117). / Text in English; abstracts in English and Chinese. / Siu Ming Fai Parco. / Acknowledgments --- p.i / Abstract --- p.iii / Table of Contents --- p.vii / List of Tables --- p.ix / List of Figures --- p.x / Chapter CHAPTER ONE --- Introduction --- p.1 / Research Background --- p.1 / Purpose of the Study --- p.6 / Hypotheses --- p.6 / Definition of Terms --- p.7 / Assumptions --- p.8 / Delimitations --- p.9 / Limitations --- p.9 / Chapter CHAPTER TWO --- Review of Literature --- p.10 / Importance of Muscle Glycogen Resynthesis During Recovery from Exercise --- p.10 / Factors Affecting Muscle Glycogen Resynthesis --- p.10 / Muscle Glycogen Resynthesis and Subsequent Endurance Capacity --- p.17 / Importance of Rehydration on Recovery from exercise --- p.22 / Factors Affecting Rehydration --- p.22 / Rehydration and Subsequent Endurance Capacity --- p.25 / Glycemic Index Foods and Exercise --- p.26 / Definition of Glycemic Index (GI) --- p.26 / Ingestion of GI Foods Before Exercise --- p.28 / Ingestion of GI Foods During Recovery --- p.33 / Frequency of CHO Ingestion and Exercise --- p.36 / Chapter CHAPTER THREE --- Methodology --- p.39 / Participants --- p.39 / Equipment and Instrumentation --- p.39 / Preliminary Measurements --- p.40 / Dietary Analysis and Training Control --- p.45 / Preliminary Testing --- p.46 / Standardized Experimental Procedure --- p.51 / Collection and Analysis of Blood Sample --- p.57 / Statistical Analysis --- p.61 / Chapter CHAPTER FOUR --- Results --- p.62 / Run Time to Exhaustion --- p.63 / Dietary Analysis --- p.63 / Postprandial Responses of the Prescribed Foods During Screening Test --- p.64 / Postprandial Responses During Recovery of Main Trial --- p.67 / Metabolic and Physiological Responses During Exercise and Recovery --- p.70 / "Body Mass Change, Fluid Balance and Urine Volume" --- p.89 / Changes in Plasma Volume --- p.90 / Summary of the Results --- p.91 / Chapter CHAPTER FIVE --- Discussion --- p.92 / Recommendations and Applications --- p.99 / References --- p.101 / Appendices --- p.118
436

Effets de l'entraînement physique périnatal sur la santé métabolique de la descendance : composition corporelle, fonction pancréatique et gestion des substrats énergétiques / Effects of perinatal exercise on offspring metabolic health : body composition, pancreatic function and energy substrates management.

Quiclet, Charline 24 October 2016 (has links)
Les maladies métaboliques sont en pleine expansion dans nos sociétés actuelles et constituent un enjeu de santé publique majeur. Les antécédents familiaux, l'environnement et les habitudes de vie de l'individu vont jouer un rôle dans la susceptibilité à certains de ces désordres métaboliques. Sur la base de données épidémiologiques, un lien a été établi entre environnement durant les premières phases de la vie et survenue de pathologies à l'âge adulte conduisant au concept de DOHaD. L'objectif de ce travail était d'étudier, à partir d'un modèle murin, les conséquences de l'exercice physique quotidien de la mère pendant la gestation ou la lactation sur la composition corporelle, la fonction pancréatique et la gestion des substrats énergétiques de la descendance à plus ou moins long terme. L'entraînement maternel avant et pendant la gestation est associé à des modifications de la structure et de la fonction du pancréas de la descendance et semble modifier sa gestion des substrats énergétiques à tous les âges. L'exercice de la mère est également associé à une moindre prise de poids de la descendance et limite sa prise de masse grasse lorsqu'elle est soumise à un régime gras et sucré. L'exercice physique de la mère durant la lactation va modifier la composition du lait et la fonction pancréatique de la descendance. Cependant, il est associé à une augmentation du poids corporel de la descendance adulte mais semble la protéger contre l'insulino-résistance induite par la séparation maternelle. La pratique d'un exercice physique quotidien pendant la gestation et/ou la lactation semble donc modifier le développement et la maturation de certains organes (pancréas, tissu adipeux, foie, muscle squelettique) de la descendance ainsi que sa gestion des substrats énergétiques. Les conséquences de cet entraînement maternel sur la descendance vont être plus ou moins bénéfiques selon son âge et selon son environnement nutritionnel. Ce travail de thèse vient compléter les travaux menés dans le cadre des DOHaD et renforce l'idée que l'environnement lors des premières phases de la vie va avoir des conséquences à plus ou moins long terme sur la santé de l'individu. / Prevalence of metabolic diseases is growing up in our modern societies and constitutes a major public health concern. Family history, environment and lifestyle play a role in the susceptibility to several metabolic disorders. Based on epidemiological data, a link has been established between the environment during the first stages of life and diseases occurrence in adulthood leading to the concept of DOHaD. The aim of this work was to study, using a murine model, the effect of daily maternal exercise during gestation or lactation on offspring body composition, pancreatic function and energy substrates handling on a short- and a long-term basis. Maternal training before and during gestation is associated with changes in offspring pancreas structure and function and in energy substrates handling at all ages. Maternal exercise also decreases offspring body weight gain and fat mass gain when exposed to a high-fat/high sucrose diet. Maternal physical exercise during lactation modifies milk composition and offspring pancreatic function. However, it is associated to an increase in offspring body weight in adulthood but seems to protect against the insulin resistance induced by maternal separation. In conclusion, daily physical exercise during gestation and/or lactation modifies offspring organs development and maturation (such as pancreas, adipose tissue, liver, skeletal muscle) and its energy substrates handling. Maternal training consequences on offspring can be either beneficial or deleterious depending on its age and on its nutritional environment. This work is complementary to studies conducted in the framework of the DOHaD concept and strengthens the idea that the environment during the first stages of life will have short- to long-term impacts on the health of the individual.
437

Utilização da técnica infravermelho com transformada de Fourier (FTIR) para estimativa das concentrações de carboidratos e de lipídeos em scenedesmus sp.

Cougo, Cecília Dutra Garcia January 2017 (has links)
Com as descobertas das inúmeras aplicações potenciais da biomassa de microalgas é necessário o desenvolvimento de ferramentas que visem auxiliar o aumento da produtividade dos cultivos. A espectrometria por infravermelho com transformada de Fourier (FTIR) é uma técnica versátil e rápida utilizada na identificação, caracterização e quantificação de diversos compostos moleculares. Sua aplicação está definida de acordo com a região espectral a ser analisada. O objetivo deste trabalho é desenvolver uma metodologia que torne possível a utilização da espectroscopia FTIR na região do infravermelho médio (MIR) para quantificar os teores de lipídeos, proteínas, carboidratos e células de Scenedesmus sp. Para tanto, a biomassa de Scenedesmus sp. foi analisada diariamente por métodos tradicionais e através do espectro FTIR. Posteriormente os dados foram correlacionados com as bandas de absorção características de cada composto. O modelo gerado para lipídeos na região entre 3000-2800 cm-1 obteve o maior coeficiente de correlação (R2) de 0,8265. Para os carboidratos, a banda de absorção que melhor representou as ligações características foi entre 1200-950cm-1, com R2=0,8023. Já para proteínas, a escolha do método tradicional não mostrou boa relação com os resultados do FTIR. Quando a concentração celular foi correlacionada com a área total foi obtido R2=0,7900. Por fim, realizaram-se experimentos para validar os modelos preditos, obtendo bons resultados para a quantificação de lipídeos e carboidratos. O FTIR mostra ser uma ferramenta eficiente para estimar os conteúdos de lipídeos e carboidratos de Scenedesmus sp. Além disso, o FTIR permite análise simultânea de múltiplos metabolitos que permitirá o monitoramento mais detalhado do cultivo em um tempo de análise muito mais curto e com alta reprodutibilidade dos resultados. / With the discoveries of the numerous potential applications of microalgal biomass, it is necessary to develop tools to help increase the productivity of cultivation. Infrared spectrometry with Fourier transform (FTIR) is a versatile and fast technique used in the identification, characterization and quantification of several molecular compounds. Its application is defined according to the spectral region to be analyzed. The objective of this work is to develop a methodology that makes possible the use of FTIR spectroscopy in the medium infrared region (MIR) to quantify lipid, protein, carbohydrate and cells contents of Scenedesmus sp. For this, the Scenedesmus sp. biomass was analyzed daily by traditional methods and through the FTIR spectrum. Subsequently the data were correlated with the absorption bands characteristic of each compound. The model generated for lipids in the region between 3000-2800 cm-1 obtained the highest coefficient of correlation (R2) of 0.8265. For carbohydrates, the absorption band that best represented the characteristic bonds was between 1200-950cm-1, with R2=0.8023. For proteins, the choice of the traditional method did not show a good relation with the FTIR results. When the cell concentration was correlated whit the total area an R2=0.7900. Finally, experiments were carried out to validate the predicted models, obtaining good results for the quantification of lipids and carbohydrates. The FTIR shows to be an efficient tool to estimate lipid and carbohydrate contents of Scenedesmus sp. In addition, the FTIR allows simultaneous analysis of multiple metabolites that will enable more detailed monitoring of the cultivation in a much shorter analysis time and with high reproducibility of the results.
438

Novos tensoativos não-iônicos para CO2-supercrítico: síntese e estudo de algumas propriedades / New nonionic surfactants for supercritical CO2: synthesis and study of some properties

Cordeiro, Tiago de Angelis 11 May 2012 (has links)
O CO2 supercrítico (CO2-sc) é um bom solvente para substâncias apolares e pouco polares de baixa massa molecular. A fim de tornar este meio um melhor solvente para uma gama maior de substâncias, desenvolvemos 8 novos tensoativos, sendo seis derivados de açúcares (N-metil-D-glucamina, 2-D-Glucosamina e Sorbitano) e três derivados de óleos vegetais (linhaça e palma). Os tensoativos possuem como grupos CO2-fílicos, o acetato (peracetilados) ou o t-butil-glicidil-éter, e como grupo CO2-fóbico o dodecanoato, que pode proporcionar um ambiente \"apolar\" em eventuais agregados formados em CO2-sc. A solubilidade e o comportamento de fase destes novos tensoativos em CO2-sc foram investigados, mostrando-se bastante solúveis e apresentando pontos de névoa comparáveis a outros tensoativos fluorados (mais agressivos, do ponto de vista ambiental). A polaridade que estes tensoativos agregam ao meio foi verificada através de análises de solvatocromismo, utilizando o corante de Reichardt (Betaína-30) e fluorescência de pireno, as quais mostraram resultados bastante promissores, obtendo-se polaridades baixas e médias (similares a álcoois de cadeia média ou solventes clorados). / Supercritical CO2 (sc-CO2) is a good solvent for non-polar or almost non-polar substances with low molecular mass. In order to turn this medium into a better solvent for a wider range of substances, we developed 8 new surfactants, six of them sugar derivatives (N-methyl-D-glucamine, 2-D-Glucosamine and Sorbitan), and three of them vegetable oil derivatives (palm and linseed). The surfactants have either acetate (peracetylated) or t-butyl-glycidyl ether as CO2-philic groups, and as CO2-phobic group, dodecanoate, that can provide an \"apolar\" environment in aggregates that might be formed in sc-CO2. The solubility and phase behavior of these new surfactants in sc-CO2 were investigated, and they showed to be very soluble presenting low cloud pressures comparable to fluorinated surfactants (that are more aggressive from an environmental perspective). The polarity that these new surfactants brought to the medium was verified through the solvatochromic analysis, using the Reichardt\'s dye (Betaine-30) and pyrene fluorescence, which showed promising results, with polarities similar to medium chain alcohols or chlorinated solvents
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Effect of consumption of carbohydrate-electrolyte solution on running performance after pre-exercise glycemic index meal. / 運動前進食不同血糖指數食物及運動中補充碳水化合物飲料對長跑能力的影響 / Effect of consumption of carbohydrate-electrolyte solution on running performance after pre-exercise glycemic index meal. / Yun dong qian jin shi bu tong xue tang zhi shu shi wu ji yun dong zhong bu chong tan shui hua he wu yin liao dui chang pao neng li de ying xiang

January 2004 (has links)
Chan Oi Wan = 運動前進食不同血糖指數食物及運動中補充碳水化合物飲料對長跑能力的影響 / 陳靄允. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 72-91). / Text in English; abstracts in English and Chinese. / Chan Oi Wan = Yun dong qian jin shi bu tong xue tang zhi shu shi wu ji yun dong zhong bu chong tan shui hua he wu yin liao dui chang pao neng li de ying xiang / Chen Aiyun. / Acknowledgments --- p.i / Abstract --- p.iii / Table of Contents --- p.vii / List of Figures --- p.ix / List of Tables --- p.x / Chapter Chapter One --- Introduction --- p.1 / Chapter 1.1 --- Background --- p.1 / Chapter 1.2 --- Purpose --- p.5 / Chapter 1.3 --- Significance of the Study --- p.5 / Chapter Chapter Two --- Review of Literature --- p.6 6 / Chapter 2.1 --- "Energy Metabolism during Prolonged, Submaximal Exercise" --- p.6 / Chapter 2.2 --- Importance of Nutrition on Exercise Performance --- p.9 / Chapter 2.3 --- Application of GI --- p.20 / Chapter CHAPTER Three --- Methodology --- p.36 / Chapter 3.1 --- General Methods --- p.36 / Chapter 3.2 --- Preliminary Testing --- p.42 / Chapter 3.3 --- Subjects --- p.45 / Chapter 3.4 --- Experimental Design --- p.46 / Chapter 3.5 --- Procedures --- p.47 / Chapter 3.6 --- Prescribed Meals --- p.50 / Chapter 3.7 --- Prescribed CHO-electrolyte Drink --- p.50 / Chapter 3.8 --- Statistical Analysis --- p.51 / Chapter Chapter Four --- Results --- p.52 / Chapter 4.1 --- Dietary Analysis --- p.52 / Chapter 4.2 --- Running Performance --- p.52 / Chapter 4.3 --- Blood Metabolites --- p.53 / Chapter 4.4 --- Metabolic Responses --- p.60 / Chapter 4.5 --- Subjective Responses and Heart Rates Responses --- p.61 / Chapter Chapter Five --- Discussion --- p.64 / Recommendations and Applications --- p.70 / References --- p.72 / Appendices --- p.95
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Eficiência de herbicidas inibidores da ALS e PROTOX sob condições de déficit hídrico no comportamento bioquímico de plantas daninhas

Vitorino, Hermeson dos Santos [UNESP] 24 February 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:14Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-24Bitstream added on 2014-06-13T19:48:22Z : No. of bitstreams: 1 vitorino_hs_me_botfca.pdf: 1010025 bytes, checksum: ebb8cca22a8439d8a7f6d2ab0925617d (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O objetivo deste estudo foi o de avaliar em condições de casa de vegetação a eficiência de herbicidas inibidores das enzimas acetolactato sintase (ALS) e protoporfirinogênio oxidase (PROTOX) em pós-emergência em plantas de Euphorbia heterophylla, Bidens pilosa e Ipomoea grandifolia quando submetidos a déficit hídrico, bem como a ação destes sobre algumas características bioquímicas. O delineamento experimental utilizado foi inteiramente casualizado em esquema fatorial 4x2, sendo quatro herbicidas utilizados (fomesafen, lactofen, chlorimuron-ethyl e imazethapyr) e dois níveis de déficit hídrico: com déficit (-0,5 MPa) e sem déficit (-0,01 MPa). Quando as plantas daninhas atingiram o estádio de um par de folhas definitivas a manutenção da umidade do solo nos dois níveis de cada tratamento. Aos 7, 14, 21 e 28 dias após a aplicação (DAA) dos herbicidas foi avaliado o controle (por escala visual) e aos 28 DAA a massa seca da parte aérea. As plantas utilizadas para a determinação dos solutos orgânicos (carboidratos solúveis, proteínas totais e aminoácidos livres) foram coletadas às 24, 48, 72 e 96 horas após a aplicação (HAA). Todos os herbicidas controlaram as plantas daninhas de I. grandifolia, enquanto que apenas os inibidores da PROTOX foram eficientes no controle de E. heterophylla, contudo para as plantas de B. pilosa o fomesafen foi o único herbicida que proporcionou um controle satisfatório. O déficit hídrico reduziu o controle de todos herbicidas estudados. Tanto o déficit hídrico como a aplicação de herbicidas aumentaram o conteúdo de carboidratos solúveis em todas as plantas estudadas. O teor de proteínas encontrado nas plantas daninhas estudadas foi reduzido pelo déficit hídrico e a aplicação dos herbicidas, enquanto que para as concentrações de aminoácidos livres os herbicidas proporcionaram um incremento nessa concentração... / The objective of this work was to evaluate conditions in the greenhouse the efficiency of herbicides inhibitors of acetolactate synthase (ALS) and protoporphyrinogen oxidase (PROTOX) post-emergence in plant of Euphorbia heterophylla, Ipomoea grandifolia and Bidens pilosa when subjected to water deficit, as well as to determine the effect of these on some biochemical characteristics. The experimental design was randomized blocks in factorial scheme 4x2, with four herbicides (fomesafen lactofen, chlorimuron-ethyl and imazethapyr), and two levels of water deficit: with deficit (-0,5 MPa) and no deficit (-0,01MPa). When weeds reached the stage of a pair of true leaves to maintain soil moisture at the two leaves of each treatment. At 7, 14, 21 and 28 days after application (DAA), was evaluated the control (a visual scale), and 28 DAA, the dry weight of shoots. The plants used for the determination of organics solutes (soluble carbohydrates, protein and free amino acids) were collected at 24, 48, 72 and 96 hours after application (HAA). All herbicides controlled the weeds of I. grandifolia whereas only PROTOX inhibitors were effective in control of E. heterophylla, however, to plants of B. pilosa fomesafen was the single that provided satisfactory control. Water deficit reduced the control of all the herbicides. Both the water deficit and herbicide application increased the soluble carbohydrate content in all species studied. The protein found in the weeds studied were reduced by water deficit and herbicide application, whereas for concentrations of free amino acids the herbicides have provided an increase in this concentration, but with respect to water deficit caused reduction of amino acids, except for plants B. pilosa

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