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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.
331

Comparação entre técnicas de secagem para a obtenção de biomassa de rubrivivax gelatinosus /

Espirito Santo, Edson Francisco do. January 2011 (has links)
Orientador: Elisa Helena Giglio Ponsano / Banca: Antonio Carlos de Laurentiz / Banca: Roberto da Silva / Resumo: A cor de um alimento é de suma importância para a sua aceitação, pois serve como critério de qualidade. Os pigmentantes, ao serem adicionados na produção animal melhoram a coloração dos produtos e a aceitação pelo mercado consumidor. Tais aditivos podem ser elaborados a partir de diversas origens, inclusive de resíduos industriais, e podem ser processados por diferentes técnicas de secagem. Este estudo teve como objetivo comparar dois métodos de retirada de umidade da biomassa de Rubrivivax gelatinosus produzida em efluente de indústria de processamento de pescado, liofilização e atomização, em relação a rendimento do processo e recuperação, cor, composição químico-bromatológica e concentração de oxicarotenóides dos produtos. A bactéria foi cultivada nas águas residuárias citadas, sob condições de anaerobiose, temperatura e luminosidade controladas. Ao final do processo, a biomassa bacteriana foi processada por microfiltração e transformada em pó por meio de liofilização ou atomização. As técnicas não diferiram entre si em relação ao rendimento. A maior recuperação do produto (p = 0,004) e a mais elevada umidade (p = 0,0022) foram obtidas pela técnica de liofilização. As porcentagens de matéria mineral (p < 0,0001) e todos os parâmetros de cor (p < 0,0001) foram maiores para o produto obtido por atomização. Os outros constituintes analisados não diferiram significativamente entre as técnicas. Os resultados obtidos demonstraram que, apesar de resultar em menor recuperação, a atomização foi um processo mais rápido que a liofilização, apresentou rendimento equivalente a esta e originou um produto semelhante ao liofilizado em relação à composição químico-bromatológica e pigmentante. Este novo produto pode ser alvo de estudos posteriores para avaliar sua aplicação como componente pigmentante de ração animal / Abstract: The color of a food is parameter of acceptance, because it serves as a quality criterion for the consumers. Pigments are added to animal feeding in order to improve the color of the products and, so, its acceptance. These additives can be made from various sources, including industrial wastes, and can be processed by different drying techniques. This study aimed at comparing two methods of water removal from Rubrivivax gelatinosus biomass produced in the effluent from fish processing industry, lyophilization and spray drying. Parameters analyzed were: process yield, recuperation, color, proximate composition and oxycarotenoids concentration of the products. The bacterium was grown in the wastewater under anaerobiosis and controlled temperature and light conditions. At the end of the process, the bacterial biomass was prepared by microfiltration and dried by freeze and spray drying. No difference was detected for yield between the drying techniques. The higher recuperation of the product (p = 0.004) and the higher moisture content (p = 0.0022) were achieved with lyophilization. The percentages of ash (p < 0.0001) and all color parameters (p < 0.0001) were higher for the product obtained by spray drying. The other constituents analyzed did not differ significantly. The results showed that, although resulting in less recuperation, the spray drying process was faster than lyophilization, had the same yield and produced a biomass similar to the lyophilized one in relation to composition and pigment concentration. This new product can be subjected to further studies to evaluate its use as a pigmenting component of animal feed / Mestre
332

Estudos dos pigmentos visuais de macaco-prego (cebus sp) e da relação entre a psicofísica e a genética da visão de cores em humanos / Study of the visual pigments from capuchin monkey (Cebus sp) and the psychophysics and the genetics colour vision relationship in humans

Bonci, Daniela Maria Oliveira 03 March 2011 (has links)
A visão de cores é possível devido aos diferentes tipos de fotorreceptores e ao processamento pós-receptoral da informação gerada após ativação destas células pela luz. Análises genéticas, funcionais e morfológicas podem ser utilizadas no estudo da visão de cores. Neste trabalho, foram estudadas a genética dos pigmentos visuais de macacos do gênero Cebus e a genética e a psicofísica da visão de cores de humanos com e sem discromatopsias hereditárias. O sequenciamento dos genes que expressam as opsinas presentes nos cones L e M foi realizado em dois grupos de macacos-prego mantidos na UFRJ e na UFPA. Treze animais do Instituto de Biofísica Carlos Chagas Filho da UFRJ e vinte animais da Escola de Primatas da UFPA tiveram o sangue coletado, o material genético extraído e os éxons 3 e 5 dos genes que codificam as opsinas L/M sequenciados após amplificação por PCR. Os aminoácidos localizados nas posições 180, 277 e 285 das opsinas foram identificados e com este resultado foi determinada a curva de absorção espectral das opsinas. O resultado foi a caracterização de seis machos dicromatas, quatro fêmeas tricromatas e três fêmeas dicromatas entre os animais da UFRJ. Entre os animais da UFPA, dezesseis machos eram dicromatas, uma fêmea era tricromata e três fêmeas eram dicromatas. Entre os alelos encontrados nesses grupos, a combinação SFT, cujo pico de absorção espectral da opsina é de 546-553, foi descrita pela primeira vez no gênero Cebus. A variedade de alelos encontrada entre os dois grupos é devida às diferentes condições ambientais nos locais de origem dos animais. No estudo com humanos, a visão de cores de 19 sujeitos controles (5 homens e 14 mulheres) e 16 sujeitos daltônicos (14 homens e 1 mulher), moradores no estado de São Paulo (SP) foi avaliada através de quatro testes psicofísicos e análises genéticas dos pigmentos visuais. Estes resultados foram comparados com os dados descritos por Gonçalves (2006) em sujeitos daltônicos do estado do Pará (PA). Na correlação entre o fenótipo e o genótipo dos sujeitos estudados neste trabalho, foi observada uma correspondência de 100% entre a classificação da discromatopsia obtida com as análises genéticas e os testes psicofísicos / Color vision is possible due to different types of photoreceptors and to the post receptoral processing of the information generated after cell activation by the light. Genetic, functional and morphological analysis can be used as tools in the color vision studies. In the present work the genetic of the visual pigments from Cebus sp and the genetic and the psychophysics of normal and defective human color vision were evaluated. The sequencing of the L and M genes of 33 capuchin monkeys was performed. Blood samples were collected from 13 monkeys from Instituto de Biofísica Carlos Chagas Filho (UFRJ) and 20 monkeys from Escola de Primatas (UFPA), the DNA was extracted and exons 3 and 5 from L/M genes were sequenced after PCR amplification. For each animal the 180, 277 and 285 aminoacids were identified and the spectral absorbance curve was estimated based on their sequence. In the UFRJ group, six males and three females were identified as dichromats and four females were identified as thrichromats. In the UFPA group sixteen males and three females were dichromats and one female was thrichromat. The SFT aminoacid combination was described for the first time in the Cebus genera. The allelic diversity described in these animals is probably due to the distinct environmental conditions from the place of birth of the animals. In the human study 19 control subjects (5 men and 14 women) and sixteen daltonic subjects (14 men and 1 woman), all from São Paulo city, had the colour vision evaluated with 4 colour vision tests and with the visual pigment genetics. The results were compared to the data described by Gonçalves (2006) in daltonic subjects from Pará state. The correlation between phenotype and genotype of the subjects from SP had a 100% of correspondence in the genetic and psychophysical classifications of dischromatopsia
333

Avaliação da variabilidade de biotipos de Moniliophthora perniciosa / Evaluation of Moniliophthora perniciosa biotypes variability

Lia Matelli Garcia 04 February 2010 (has links)
O basidiomiceto Moniliophthora perniciosa é conhecido por causar a doença vassoura-debruxa no cacau (Theobroma cacao), responsável por grandes perdas de produção nessa cultura. A população de M. perniciosa apresenta variabilidade devido à sua capacidade de colonização de outras espécies de plantas, o que permite a identificação de biótipos e conseqüente agrupamento de isolados com base no hospedeiro. A caracterização de biotipos do fungo contribui para melhor conhecimento da estrutura populacional e sua dispersão, o que é importante para utilização em programas de melhoramento. Com esse objetivo foi avaliada a variabilidade genética e fisiológica de isolados do fungo correspondentes a três biotipos considerando a análise de taxas de crescimento pelo desenvolvimento micelial em diferentes meios e ambientes de cultivo in vitro, como a incorporação de cisteína, metionina e lisina e das fontes de nitrogênio tartarato de amônio e nitrato de potássio, iluminação, suscetibilidade a fungicidas, compatibilidade somática (SCG Grupo de Compatibilidade Somática), análise de perfis protéicos por SDS-PAGE e seqüenciamento parcial do 28S rDNA. A história evolutiva do patógeno não está registrada em seqüências de genes ribossomais e proteínas totais. Além disso, crescimento e produção de pigmentos são características compartilhadas pelos biótipos, não sendo fatores primários para adaptação do patógeno, porém com provável papel na colonização do hospedeiro. / The Basidiomycete Moniliophthora perniciosa is known as the pathogen for witches\' broom disease in cocoa (Theobroma cacao), responsible for large yield losts. Population of M. perniciosa presents variability due to its ability to colonize other plant species, which allows biotype identification and strains grouping, based upon the host specie. Fungi biotype characterization contributes to the knowledge of population and its dispersion and epidemiological methods, important for breeding programs. To aim the genetic and physiological variability of three strains, characteristics as growing rates, measured by the mycelia spreading at different culture media and different culture conditions in vitro, cysteine, methionine, lysine, nitrogen sources ammonium tartrate and potassium nitrate incorporation, light, fungicide susceptibility, somatic compatibility (SCG), protein patterns by SDS-PAGE and partial sequencing of rRNA 28S region were done. The evolutional history of it is pathogen is not printed into ribosomal genes sequences and total proteins. Besides that, growing and dye production are characteristics shared by the biotypes and can not be a primary adaptation factor but it can play a role in the host colonization process.
334

Germinação, desenvolvimento inicial e concentração de pigmentos em mudas de physalis (Physalis spp.) produzidas em diferentes ambientes / Germination, development initial and concentration of pigments in seedlings of cape gooseberry (Physalis spp.) produced in different environments

Mezzalira, Éder Júnior 26 February 2013 (has links)
Made available in DSpace on 2017-07-10T17:36:47Z (GMT). No. of bitstreams: 1 2013_Eder_Junior_Mezzalira.pdf: 952924 bytes, checksum: 2099d1de32bf14a58a2d5de9c422d683 (MD5) Previous issue date: 2013-02-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The use of different environments can be a limiting factor for the development of seedlings of species of Cape gooseberry. Given the above, the objective of the present study to evaluate the initial development of species of physalis, subjected to different environments. The experimental design was randomized blocks, in 3 x 3 factorial schemes, containing four repetitions. The experiment conducted in the period from February to May 2012 in Horticultural and Biological Control Station "Professor Mário César Lopes", belonging to Unioeste, Campus, in Marechal Cândido Rondon-PR. Treatments were composed of three species of Cape gooseberry (Physalis peruviana, p. angulata and p. pubescens) x three environments (greenhouse/EST-colorless plastic coated 150 microns; sombrite/SBT-75% of the light permeability and full sun/PLS-local fully open), being monitored the emergency speed index of seedlings in 30 days. To 76 days after sowing evaluated the leaf area, dry weight of leaves, stems, and roots and counting the number of leaves, plant height and stem diameter. For the determination of biochemical levels of chlorophyll a and b, anthocyanin, carotenoids polifenoloxidase, peroxidase and proteins. Collected into plant tissue of leaves, before sunrise, between the 05:00 and 6:30 hs, having been put up in aluminum foil, properly identified the treatments, which is stored in the container with ice and then frozen. The environment sombrite provides highest rate for the species of Physalis angulata, p. peruviana and p. pubescens. The environments and sombrite were very similar in initial development to Physalis angulata, p. peruviana and p. pubescens and may be used for the production of seedlings of these species. The Physalis peruviana has the largest average levels of all photosynthetic pigments, compared to p. angulata. The Physalis peruviana has been greater than p. pubescens, in relation to carotenoids. The average levels of total protein of p. angulata overcame the other species. In General, species of physalis plants kept in the EST and SBT, outweigh the environment PLS / A utilização de diferentes ambientes pode ser um fator limitante para o desenvolvimento de mudas de espécies de physalis. Diante do exposto, objetivou-se com o presente trabalho avaliar desenvolvimento inicial de espécies de physalis, submetidas a diferentes ambientes. O delineamento experimental utilizado foi blocos casualizados, em esquema fatorial 3 x 3, contendo quatro repetições. Conduziu-se o experimento no período de fevereiro a maio de 2012, na Estação de Horticultura e Controle Biológico Professor Mário César Lopes , pertencente à Unioeste, Campus Marechal Cândido Rondon, PR. Os tratamentos foram compostos de três espécies de physalis (Physalis peruviana, P. angulata e P. pubescens) x três ambientes (estufa/EST - com cobertura plástica incolor de 150 micras; sombrite/SBT - 75% de permeabilidade à luz e pleno sol/PLS - local totalmente aberto), sendo monitorado o índice de velocidade de emergência das plântulas nos 30 dias iniciais. Aos 76 dias após a semeadura avaliaram-se a área foliar, matéria seca das folhas, caules, raízes e a contagem do número de folhas, altura de planta e diâmetro do caule. Para a determinação dos teores bioquímicos de clorofila a e b, antocianina, carotenóides, polifenoloxidase, peroxidase e proteínas. Coletou-se parte de tecido vegetal das folhas, antes do nascer do sol, entre as 5:00 e 6:30 hs da manhã, tendo sido acondicionado em papel alumínio, devidamente identificado os tratamentos, armazenado em recipiente com gelo e, em seguida congelado. O ambiente sombrite propicia maior taxa de emergência para as espécies de Physalis angulata, P. peruviana e P. pubescens. Os ambientes, estufa e sombrite foram muito similares no desenvolvimento inicial para Physalis angulata, P. peruviana e P. pubescens podendo ser utilizados na produção de mudas destas espécies. A Physalis peruviana apresentou maiores níveis médios de todos os pigmentos fotossintetizantes, comparados a P. angulata. A Physalis peruviana foi superior a P. pubescens, em relação aos carotenóides. Os níveis médios de proteína total de P. angulata superou as demais espécies. De modo geral, as mudas espécies de physalis mantidas no ambiente EST e SBT, superam o ambiente PLS
335

Production and regulation of fouling inhibitory compounds by the marine bacterium Pseudoalteromonas tunicata

Egan, Suhelen, Microbiology & Immunology, UNSW January 2001 (has links)
The marine surface-associated bacterium Pseudoaltermonas tunicata, produces a range of compounds that inhibit fouling organisms, including invertebrate larvae, bacteria, algal spores and fungi. In addition to these antifouling compounds P. tunicata cells produce both a yellow and a purple pigment. The aim of this study was to further characterise the antifouling activities, their regulation and relationship with pigmentation, and the ecological significance of P. tunicata and related organisms. It was discovered that the anti-algal compound was extracellular, heat sensitive, polar and between 3 and 10 kDa in size. The anti-fungal compound was found to be the yellow pigment and active against a wide range of fungal and yeast isolates. Chemical analysis suggests that this compound consists of a carbon ring bound to a fatty-acid side chain. Genetic analysis supports the chemical data for the active compound as a mutant in a gene encoding for a long-chain fatty-acid CoA ligase was deficient for anti-fungal activity. To address the regulation of antifouling compounds and their relationship to pigmentation transposon mutagenesis of P. tunicata was performed. Mutants lacking the yellow pigment displayed a reduced ability to inhibit fouling organisms. Further analysis of these mutants identified genes involved with the synthesis and regulation of synthesis of pigment and antifouling compounds. One of these mutants was disrupted in a gene (wmpR) with similarity to the transcriptional regulators ToxR from Vibrio cholerae and CadC from Escherichia coli. Analysis of global protein expression using two-dimensional gel electrophoresis showed that WmpR is essential for the expression of at least fifteen proteins important for the synthesis of fouling inhibitors. The ecological significance of antifouling bacteria was addressed by assessing the antifouling capabilities of a collection of bacteria isolated from different marine surfaces. Overall, isolates from living surfaces displayed more antifouling traits then strains isolated from non-living surfaces. Five dark-pigmented strains originating from the alga Ulva lactuca were further studied. Phylogenetic and phenotypic analysis revealed that they were all members of the genus Pseudoalteromonas and were closely related to P. tunicata. Two strains represented a novel species within the genus and were taxonomically defined as P. ulvae sp. nov.
336

Elaboration, caractérisation et développement de nouveaux grades de pigments aluminium

Morvan, Fabrice 18 January 2002 (has links) (PDF)
La prise de conscience des problèmes écologiques liés à l'émission de solvants dans l'atmosphère a<br />provoqué la mise en place d'un cadre législatif auquel les fabricants de peintures ont dû s'adapter.<br />L'évolution vers l'utilisation des peintures en phase aqueuse n'a pu être réalisée sans des aménagements tant au niveau des procédés que des produits. Ainsi, les pigments aluminium mis en oeuvre dans les peintures métallisées, principalement destinées à l'industrie automobile, doivent subir des traitements préalables leur permettant d'éviter des phénomènes de corrosion préjudiciables tant du point de vue esthétique que de la sécurité (dégagement d'hydrogène). Les traitements proposés jusqu'ici (composés phospho-organiques, dérivés du chrome hexavalent) ne sont pas exempts de défauts (toxicité). Cette étude a permis de montrer que l'encapsulation des pigments aluminium dans une coque de PMMA par un procédé dérivé de la polymérisation en émulsion permet d'obtenir des pigments stables en phase aqueuse. De plus, la mise au point d'un nouveau procédé de production , mettant en oeuvre des agents silaniques au cours de l'étape de broyage, permet désormais d'envisager l'élaboration d'un grade universel, i.e. adapté pour les<br />peintures en phase aqueuse et solvant.
337

Détermination des propriétés optiques de matériaux granulaires

Jarrige, Raphaëlle 29 November 2012 (has links) (PDF)
La caractérisation de matériaux diffusants, tels les pigments, par leur indice optique complexe demeure actuellement un véritable challenge. Cet indice est la caractéristique intrinsèque au matériau, et est de ce fait, indispensable pour la simulation d'effets colorés et peut, dans le champ de la conservation-restauration, permettre la mise en place d'une méthode d'identification non-ambigüe des matériaux composant les œuvres d'art. L'objectif de cette recherche est d'élaborer une méthodologie permettant de déterminer l'indice optique complexe de ce type de matériaux. Elle constitue l'étape primordiale à l'élaboration d'une base de données d'indices optiques des pigments. Dans un premier temps, une étude théorique des phénomènes conjoint de diffusion et d'absorption résultant de l'interaction d'une onde électromagnétique avec un diffuseur, ou un ensemble de diffuseurs homogènes et sphériques, est développée. Elle consiste à définir l'influence des paramètres intrinsèques (des matériaux) et morphologiques (d'un milieu) sur les résultats obtenus lors de la résolution de l'équation du transfert radiatif (ETR) traité par la méthode 4-flux et de la théorie de Mie dans le sens direct. Dans un second temps, nous aborderons le problème inverse. À savoir, dans notre cas, remonter à l'indice complexe de particules diffusantes à partir des propriétés optiques de la couche. Nous illustrerons cette approche par l'étude d'un pigment rouge, le cinabre. Le modèle de calcul développé prend en compte les flux diffus et les flux spéculaires, mesurés sur les échantillons par spectrophotométrie couplée à une sphère d'intégration dans le domaine du visible
338

Water Dispersed Epoxy Resin For Surface Coatings

Sen, Evrim 01 December 2003 (has links) (PDF)
In this research water dispersed epoxy varnishes were produced by reacting solid epoxy resin with ethylene diamine (EDA) and maleinized fatty acids of linseed oil. Maleinized fatty acid (MFA) was produced by the maleinization process, in which, fatty acid and maleic anhydride were reacted under nitrogen atmosphere. Maleinization was performed in order to insert hydrophilic groups to the fatty acid chains, which were then inserted to the backbone of the epoxy resin. This was done to give water dispersibility to the hydrophobic epoxy resin. Solid epoxy resin was dissolved in 1,4-dioxane. Ethylene diamine was then added to the solution at 50&deg / C, and stirred for 4 hours. Then the temperature was increased to 80oC and kept for 2 hours. Maleinized fatty acids were then introduced, and the reaction was carried out at 90oC for 10 hours. 1,4-dioxane was used for the removal of the water, which forms as the byproduct. Then the driers were added. The carboxylic groups of the maleinized fatty acid were neutralized by morpholine and the product was dispersed in water. The varnish was applied on test panels and left for air-drying for 24 hours and then baked at 140&deg / C for 5 hours. The free epoxy content was determined by pyridinium-chloride titration and it was seen that all the epoxy groups reacted. Also, produced fatty acid was characterized by FTIR spectroscopy and maleinized fatty acid was characterized by H-NMR and FTIR spectroscopy. Hardness, bending, impact resistance, gloss, and abrasion resistance tests were carried out on hardened varnish specimens. The samples generally showed good mechanical and physical properties. While the baking time was increased the hardness of product increased. Samples showed superior impact resistance, gloss, and flexibility.
339

Quantitative determination of quinone chromophore changes during ECF bleaching of kraft pulp

Zawadzki, Michael A. 08 1900 (has links)
No description available.
340

Les couches picturales stratifiées: analyse et modélisation de l'aspect visuel

Latour, Gaël 12 December 2007 (has links) (PDF)
Une peinture est un matériau complexe composé de plusieurs couches picturales. Ce travail de recherche poursuit un double but : comprendre et modéliser l'aspect visuel d'un tel milieu stratifié et développer des méthodes non destructives permettant d'identifier les différents constituants présents dans une œuvre d'art. L'équation de transfert radiatif, résolue par la méthode de la fonction auxiliaire, permet de modéliser l'aspect visuel des couches picturales stratifiées. Cette modélisation est validée par comparaison avec des spectres expérimentaux de réflexion diffuse. Expérimentalement, la reconnaissance des pigments et des colorants à partir d'un appareil déjà opérationnel au laboratoire a été étendue à celle des constituants d'un mélange de pigments. De plus, la tomographie optique cohérente (OCT), développée au cours de cette thèse, permet d'imager les pigments et d'obtenir une information spectrale permettant d'envisager une identification non destructive des composants de couches picturales stratifiées.

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