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Caracterização bioquímica e atividades biológicas de quitinases laticíferas de Calotropis procera / Biochemical characterization and biological activities of Calotropis procera laticifer chitinasesViana, Carolina de Araújo January 2015 (has links)
VIANA, Carolina de Araújo. Caracterização bioquímica e atividades biológicas de quitinases laticíferas de Calotropis procera. 2015. 181 f. Tese (Doutorado em Bioquímica)-Universidade Federal do Ceará, Fortaleza, 2015. / Submitted by Vitor Campos (vitband@gmail.com) on 2016-09-01T23:13:32Z
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Previous issue date: 2015 / Calotropis procera is a latificer plant in the Apocynaceae family. Defensive proteins with activity against phytophagous insects and phytopathogenic fungi in latex have been described. Latex’s proteic fraction also performs pharmacological activities, such as selective cytotoxic effect in carcinogenic cells. From the proteic fraction effective against neoplastic cells, this work had the goal to identify and further characterize cytotoxic protein(s) biochemically, biologically, and evaluate their biotechnological prospects. Soluble proteins in latex (LP) have been fractioned in ion-exchange matrix, and the fraction capable of cytotoxicity was further fractioned in another ion-exchange matrix (Mono-Q) coupled to a medium-pressure system. P4 was identified as cytotoxic fraction, showing an IC50 of 2.2, 1.2 and 2.9 mg/mL for the cell lines HCT-116, Ovcar-8 and SF-295, respectively. Proteomic analysis of the cytotoxic fraction by two-dimensional electrophoresis allowed 15 spots to be identified, comprising acid proteins (pI among 4 and 6) with 30 kDa apparent molecular weight. All spots were identified as chitinases when evaluated by mass spectrometry, and showed intact mass of 27.4 kDa. The sample reacted positively to the Schiff reagent, suggesting glycosilations. The carbohydrate content was estimated at 12.8%. The amino-terminal sequence obtained (1QPVMNLEYPRYLNDINDYRDDNNYD28) revealed 50% similarity with Solanum lycopersicum, Oryza sativa and Nicotiana tomentosiformes chitinases, among others. The enzymes showed strong chitinolytic activity, with optimal pH varying between 5-6 and optimal temperature of 25 °C. The chitinolytic activity was diminished when treated with increasing concentrations of DTT (3, 10 and 30 mM), which suggests the presence of disulfide bonds stabilizing the enzyme. Circular dichroism analyses indicate a larger presence of alpha helices in the structure and that the isoforms has low resistance to pH and temperature variation. High-resolution images generated through atomic force microscopy suggested sample homogeneity and a hexameric configuration. The chitinases did not inhibit mycelial growth of phytopathogenic fungi Fusarium oxysporum and Colletotrichum gloeosporioides, however reduced the germination C. gloeosporioides spores. In consonancy the chitinases did not induce spore oxidative stress, but caused a slight change in membrane permeability of the evaluated spores. Laticifer chitinases (0.1% w/w) showed a strong deleterious effect on the phytophagous insect Callosobruchus maculatus. Effects produced a 57% survival reduction, larval weight reduction (7.8 mg ± 0.2 / 4.0 ± 0.8), adult insets emergence reduction (50%), in addition to prolonging the mean maturation time from 28 to 33 days. The chitinases (2 mg/Kg, i.v.) showed a strong anti-inflammatory activity, reducing 95% of neutrophil infiltration into the peritoneal cavity in mouse in an inflammation induced by carrageenan assay. L-NAME and Aminoguanidine, two inhibitors of nitric oxide synthase, reversed this effect, possibly indicating involvement of nitric oxide in the effects observed. This action was associated to a reduction of pro-inflammatory cytokines TNF-α and IL-1 levels within the peritoneal cavity and increased serum levels of pro-inflammatory cytokines TNF-α, IL-6 and IL-1. The conclusion is reached that many isoforms of chitinases coexist in C. procera latex. These proteins act possibly in defense against insects, though low action against fungi is shown. Laticifer chitinases were identified as latex proteins cytotoxic on neoplastic cells and they have even been able to modulate pro-inflammatory cytokines levels and nitric oxide in an acute inflammation model. C. procera laticifer chitinases represent interesting molecules for biotechnology prospection in plant defense and pharmacology. / Calotropis procera é uma planta laticífera, pertencente à família Apocynaceae. Proteínas de defesa foram descritas no látex com atividade contra insetos fitófagos e fungos fitopatogênicos. A fração proteica do látex também apresenta atividades farmacológicas, dentre tais efeito citotóxico seletivo em células carcinogênicas. A partir da fração proteica efetiva sobre células neoplásicas, o trabalho teve por meta central identificar proteína(s) citotóxica(s) e proceder a sua caracterização bioquímica, biológica e suas perspectivas biotecnológicas. As proteínas solúveis do látex (PL) foram fracionadas em matriz de troca iônica e a fração proteica detentora da citotoxicidade foi refracionada em outra matriz de troca iônica (Mono-Q) acoplada a sistema de média pressão. P4 foi identificado como a fração citotóxica, apresentando uma IC50 de 2,2, 1,2 e 2,9 µg/mL para as linhagens celulares HCT-116, Ovcar-8 e SF-295, respectivamente. A análise proteômica da fração citotóxica por eletroforese bidimensional permitiu identificar 15 spots, contendo proteínas ácidas (pI entre 4 e 6) e com massa molecular aparente de 30 kDa. Quando avaliados por espectrometria de massas todos esses spots foram identificados como quitinases e apresentaram massa intacta de 27,4 kDa. A amostra reagiu positivamente ao reagente de Schiff, sugerindo glicosilações. O teor de carboidratos foi estimado em 12,8%. A sequência amino terminal obtida (1QPVMNLEYPRYLNDINDYRDDNNYD28) revelou 50% de similaridade com quitinases de Solanum lycopersicum, Oryza sativa, Nicotiana tomentosiformes dentre outras. As enzimas apresentaram forte atividade quitinolítica, com pH ótimo variando entre 5-6 e temperatura ótima de 25 °C. A atividade quitinolítica foi reduzida quando tratada com concentrações crescentes de DTT (3, 10 e 30 mM) o que sugere a presença de pontes dissulfeto estabilizadoras da enzima. Análises por dicroísmo circular indicam a presença majoritária de alfa-hélices na estrutura e que as isoformas se mostraram pouco resistentes a variações de temperatura e pH. Imagens de alta resolução geradas por microscopia de força atômica sugeriram homogeneidade na amostra e um arranjo hexamérico foi evidenciado. As quitinases não inibiram o crescimento micelial dos fungos fitopatogênicos Fusarium oxysporum e Colletotrichum gloeosporioides, mas reduziram a germinação de esporos de C. gloeosporioides. Em consonância as quitinases não induziram estresse oxidativo nos esporos, mas causaram leves alterações na permeabilidade membranar dos esporos avaliados. As quitinases laticíferas (0,1 % m/m) apresentaram forte efeito deletério sobre o inseto fitófago Callosobruchus maculatus. Os efeitos produziram 57% de redução na sobrevivência larval, redução do peso de larvas (7,8 mg ± 0,2 /4,0 ± 0,8) e emergência de insetos adultos (50%), além de prolongar de 28 para 33 dias o tempo médio de desenvolvimento de insetos adultos. As quitinases (2 mg/Kg, e.v.) apresentaram forte atividade anti-inflamatória, reduzindo em 95% a infiltração de neutrófilos na cavidade peritoneal em ensaio de inflamação induzido por carragenina em camundongos. Este efeito foi revertido por L-NAME e Aminoguanidina, dois inibidores da enzima óxido nítrico sintase, indicando o possível envolvimento do óxido nítrico no efeito observado. Esta ação foi associada à redução dos níveis das citocinas pró-inflamatórias TNF-α e IL-1 na cavidade peritoneal e do aumento dos níveis séricos das citocinas pró-inflamatórias TNF-α, IL-6 e IL-1. É concluído que várias isoformas de quitinases coexistem no látex de C. procera. Estas proteínas atuam possivelmente na defesa contra insetos, mas têm pouca ação contra fungos. As quitinases laticíferas foram identificadas como as proteínas citotóxicas do látex sobre células neoplásicas e ainda foram capazes de modular os níveis de citocinas pró-inflamatórias e síntese de óxido nítrico em modelo de inflamação aguda. As quitinases do látex de C. procera representam interessantes moléculas para prospecção biotecnológica em defesa vegetal e farmacologia.
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Metalogenia em terrenos de alto grau metamórfico: as mineralizações tungstaníferas da área de Monumento/Cacaria RJ / Metalogenia em terrenos de alto grau metamórfico: as mineralizações tungstaníferas da área de Monumento/Cacaria RJ / Metallogeny in high-grade metamorphic terrains: the scheelite mineralization in Monumento/Cacaria-RJ area. / Metallogeny in high-grade metamorphic terrains: the scheelite mineralization in Monumento/Cacaria-RJ area.Victor Muniz Alves Cruz 20 February 2015 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / Em trabalho de prospecção geoquímica regional por concentrado de bateia (PEREIRA e SANTOS, 1983) foi evidenciado na região de Cacaria, município de Piraí, ocorrências de scheelita. Com o objetivo de investigar a possível fonte litológica desta ocorrência, foram realizadas amostragens de sedimentos de corrente e concentrado de bateia além de investigações de campo para sua fonte. Elaborouse
ainda um mapa geológico em escala de detalhe 1:25.000. As unidades
estratigráficas base utilizadas no mapa foram definidas em trabalhos da empresa RIOFINEX (1977) durante pesquisas para mineralizações de Pb-Zn na região de Rio Claro. Ensaios laboratoriais envolvendo descrição de lâminas petrográficas, difratometria de raios X, fluorescência de raios X, espectrometria Raman, microscopia eletrônica de varredura e o auxílio do mineralight de ondas curtas. As mineralizações scheelitíferas encontradas foram classificadas segundo um modelo do tipo sedimentar exalativo, localmente com possíveis contribuições de atividades metassomáticas tardias, concentrando a mineralização, assim como proposto para algumas ocorrências já descritas no nordeste brasileiro. / In a mineral exploration panning concentrate programme PEREIRA AND SANTOS (1985) identified in the Cacaria region, near the Piraí City, occurences of scheelite. With the objective to investigate the lithological origin of this mineral a nonsystematic sampling by stream sediments and panning concentrate, was carried out to identify the tungsten mineralization source. A geological map was also executed at detailed scale of 1:25.000. The stratigraphic division applied to this map was defined in projects of RIOFINEX (1977) company during investigation of Pb-Zn mineralization in Rio Claro. Laboratorial trials involving description of petrography, Xray diffraction, X-ray fluorescence, Raman spectroscopy, electronic microscopy scanning and short wave mineralight. The scheelite-bearing mineralization was classified according to a exhalative sedimentary model with possible contributions of a late metasomatic activities concentrating the mineralization as proposed for some occurrences observed in northeast part of Brazil.
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Metalogenia em terrenos de alto grau metamórfico: as mineralizações tungstaníferas da área de Monumento/Cacaria RJ / Metalogenia em terrenos de alto grau metamórfico: as mineralizações tungstaníferas da área de Monumento/Cacaria RJ / Metallogeny in high-grade metamorphic terrains: the scheelite mineralization in Monumento/Cacaria-RJ area. / Metallogeny in high-grade metamorphic terrains: the scheelite mineralization in Monumento/Cacaria-RJ area.Victor Muniz Alves Cruz 20 February 2015 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / Em trabalho de prospecção geoquímica regional por concentrado de bateia (PEREIRA e SANTOS, 1983) foi evidenciado na região de Cacaria, município de Piraí, ocorrências de scheelita. Com o objetivo de investigar a possível fonte litológica desta ocorrência, foram realizadas amostragens de sedimentos de corrente e concentrado de bateia além de investigações de campo para sua fonte. Elaborouse
ainda um mapa geológico em escala de detalhe 1:25.000. As unidades
estratigráficas base utilizadas no mapa foram definidas em trabalhos da empresa RIOFINEX (1977) durante pesquisas para mineralizações de Pb-Zn na região de Rio Claro. Ensaios laboratoriais envolvendo descrição de lâminas petrográficas, difratometria de raios X, fluorescência de raios X, espectrometria Raman, microscopia eletrônica de varredura e o auxílio do mineralight de ondas curtas. As mineralizações scheelitíferas encontradas foram classificadas segundo um modelo do tipo sedimentar exalativo, localmente com possíveis contribuições de atividades metassomáticas tardias, concentrando a mineralização, assim como proposto para algumas ocorrências já descritas no nordeste brasileiro. / In a mineral exploration panning concentrate programme PEREIRA AND SANTOS (1985) identified in the Cacaria region, near the Piraí City, occurences of scheelite. With the objective to investigate the lithological origin of this mineral a nonsystematic sampling by stream sediments and panning concentrate, was carried out to identify the tungsten mineralization source. A geological map was also executed at detailed scale of 1:25.000. The stratigraphic division applied to this map was defined in projects of RIOFINEX (1977) company during investigation of Pb-Zn mineralization in Rio Claro. Laboratorial trials involving description of petrography, Xray diffraction, X-ray fluorescence, Raman spectroscopy, electronic microscopy scanning and short wave mineralight. The scheelite-bearing mineralization was classified according to a exhalative sedimentary model with possible contributions of a late metasomatic activities concentrating the mineralization as proposed for some occurrences observed in northeast part of Brazil.
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Design and characterization of a MEMS-based rotation sensor for seismic exploration / Conception et caractérisation d'un capteur de rotation MEMS pour l'exploration sismiqueProjetti, Maxime 24 March 2014 (has links)
Lors de la prospection sismique, un réseau de capteurs, utilisant principalement des géophones, est déployé à la surface libre afin d'enregistrer les ondes sismiques provenant du sous-sol. Cependant, l'énergie captée par ces géophones est largement dominée par les ondes de surface ou ondes de Rayleigh produites par la source. Étant donné leur nature, ces ondes de surface ne contiennent aucune information sur la composition des couches géologiques profondes. De ce fait, il est nécessaire d'employer un réseau très fin de capteurs dans le but de caractériser précisément ces composantes puis de les filtrer par des techniques de traitement du signal. Toutefois, les coûts engendrés nécessitent de nouvelles méthodes d'acquisition des ondes sismiques, employant moins de capteurs et permettant d'élargir le pas du réseau. Une telle technique a été mise en évidence, moyennant une mesure précise des rotations de la surface libre. La piste explorée dans ce manuscrit est l'utilisation d'un capteur MEMS haute performance pour mesurer les rotations de la surface libre, avec un coût, un poids et une consommation électrique minimaux. Plus particulièrement, le choix s'est porté sur la réalisation d'un accéléromètre angulaire, mesurant la rotation d'entrainement de son référentiel. La conception du capteur MEMS proposé utilise une technique de mesure différentielle de capacités et un contrôle en boucle fermée reposant sur la modulation ΣΔ. Un important travail de modélisation et de simulation a permis la fabrication de plusieurs prototypes qui ont ensuite été caractérisés. Une résolution fondamentale de 3 mrad.s-2 RMS dans une bande de fréquences comprises entre 60 Hz et 200 Hz a ainsi été obtenue. Les performances mesurées surpassent de loin celles d'autres accéléromètres angulaires de la littérature. Finalement, des analyses comparatives avec d'autres instruments de mesure ont permis de conclure sur la faisabilité de notre solution pour la prospection sismique. / In seismic exploration, most of the signal acquired by point-receiver geophones is dominated by surface waves or ground rolls. Because they propagate in the near surface, ground rolls do not contain any information on deeper targets. Thus, short spacing between receivers is required so that this noise component can be accurately characterized and removed by digital filtering. However, considering the cost of seismic exploration ventures, new acquisition techniques using fewer point receivers and larger spacing have to be developed. Such a technique is briefly introduced in this dissertation, requiring accurate measurements of ground rotations at the free surface with minimum cost, weight and power consumption. To address this need, the thesis proposes a high-performance rotation sensor based on MEMS technology. Unlike vibrating gyroscopes, sensitive to rotation rates through Coriolis effect, the solution developed is an angular accelerometer designed for differential capacitance measurements. A feedback controller is also implemented utilizing an oversampled ΣΔ -modulator to increase dynamic performances of the system. Thorough analytical designs along with simulations are challenged by fabricated prototypes measurements to achieve a high-sensitivity, high-resolution device. An experimental resolution of 3 mrad.s-2 RMS in the frequency band 60 Hz - 200 Hz is then obtained, which is far better than other micromachined angular accelerometers from literature. Moreover, comparison analyses are performed with specific instruments used for rotational seismology to conclude on the feasibility of a MEMS-based rotation sensor for seismic exploration.
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CaracterizaÃÃo bioquÃmica e atividades biolÃgicas de quitinases laticÃferas de Calotropis procera / Biochemical characterization and biological activities of Calotropis procera laticifer chitinasesCarolina de AraÃjo Viana 30 March 2015 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Calotropis procera à uma planta laticÃfera, pertencente à famÃlia Apocynaceae. ProteÃnas de defesa foram descritas no lÃtex com atividade contra insetos fitÃfagos e fungos fitopatogÃnicos. A fraÃÃo proteica do lÃtex tambÃm apresenta atividades farmacolÃgicas, dentre tais efeito citotÃxico seletivo em cÃlulas carcinogÃnicas. A partir da fraÃÃo proteica efetiva sobre cÃlulas neoplÃsicas, o trabalho teve por meta central identificar proteÃna(s) citotÃxica(s) e proceder a sua caracterizaÃÃo bioquÃmica, biolÃgica e suas perspectivas biotecnolÃgicas. As proteÃnas solÃveis do lÃtex (PL) foram fracionadas em matriz de troca iÃnica e a fraÃÃo proteica detentora da citotoxicidade foi refracionada em outra matriz de troca iÃnica (Mono-Q) acoplada a sistema de mÃdia pressÃo. P4 foi identificado como a fraÃÃo citotÃxica, apresentando uma IC50 de 2,2, 1,2 e 2,9 Âg/mL para as linhagens celulares HCT-116, Ovcar-8 e SF-295, respectivamente. A anÃlise proteÃmica da fraÃÃo citotÃxica por eletroforese bidimensional permitiu identificar 15 spots, contendo proteÃnas Ãcidas (pI entre 4 e 6) e com massa molecular aparente de 30 kDa. Quando avaliados por espectrometria de massas todos esses spots foram identificados como quitinases e apresentaram massa intacta de 27,4 kDa. A amostra reagiu positivamente ao reagente de Schiff, sugerindo glicosilaÃÃes. O teor de carboidratos foi estimado em 12,8%. A sequÃncia amino terminal obtida (1QPVMNLEYPRYLNDINDYRDDNNYD28) revelou 50% de similaridade com quitinases de Solanum lycopersicum, Oryza sativa, Nicotiana tomentosiformes dentre outras. As enzimas apresentaram forte atividade quitinolÃtica, com pH Ãtimo variando entre 5-6 e temperatura Ãtima de 25 ÂC. A atividade quitinolÃtica foi reduzida quando tratada com concentraÃÃes crescentes de DTT (3, 10 e 30 mM) o que sugere a presenÃa de pontes dissulfeto estabilizadoras da enzima. AnÃlises por dicroÃsmo circular indicam a presenÃa majoritÃria de alfa-hÃlices na estrutura e que as isoformas se mostraram pouco resistentes a variaÃÃes de temperatura e pH. Imagens de alta resoluÃÃo geradas por microscopia de forÃa atÃmica sugeriram homogeneidade na amostra e um arranjo hexamÃrico foi evidenciado. As quitinases nÃo inibiram o crescimento micelial dos fungos fitopatogÃnicos Fusarium oxysporum e Colletotrichum gloeosporioides, mas reduziram a germinaÃÃo de esporos de C. gloeosporioides. Em consonÃncia as quitinases nÃo induziram estresse oxidativo nos esporos, mas causaram leves alteraÃÃes na permeabilidade membranar dos esporos avaliados. As quitinases laticÃferas (0,1 % m/m) apresentaram forte efeito deletÃrio sobre o inseto fitÃfago Callosobruchus maculatus. Os efeitos produziram 57% de reduÃÃo na sobrevivÃncia larval, reduÃÃo do peso de larvas (7,8 mg  0,2 /4,0  0,8) e emergÃncia de insetos adultos (50%), alÃm de prolongar de 28 para 33 dias o tempo mÃdio de desenvolvimento de insetos adultos. As quitinases (2 mg/Kg, e.v.) apresentaram forte atividade anti-inflamatÃria, reduzindo em 95% a infiltraÃÃo de neutrÃfilos na cavidade peritoneal em ensaio de inflamaÃÃo induzido por carragenina em camundongos. Este efeito foi revertido por L-NAME e Aminoguanidina, dois inibidores da enzima Ãxido nÃtrico sintase, indicando o possÃvel envolvimento do Ãxido nÃtrico no efeito observado. Esta aÃÃo foi associada à reduÃÃo dos nÃveis das citocinas prÃ-inflamatÃrias TNF-α e IL-1 na cavidade peritoneal e do aumento dos nÃveis sÃricos das citocinas prÃ-inflamatÃrias TNF-α, IL-6 e IL-1. à concluÃdo que vÃrias isoformas de quitinases coexistem no lÃtex de C. procera. Estas proteÃnas atuam possivelmente na defesa contra insetos, mas tÃm pouca aÃÃo contra fungos. As quitinases laticÃferas foram identificadas como as proteÃnas citotÃxicas do lÃtex sobre cÃlulas neoplÃsicas e ainda foram capazes de modular os nÃveis de citocinas prÃ-inflamatÃrias e sÃntese de Ãxido nÃtrico em modelo de inflamaÃÃo aguda. As quitinases do lÃtex de C. procera representam interessantes molÃculas para prospecÃÃo biotecnolÃgica em defesa vegetal e farmacologia. / Calotropis procera is a latificer plant in the Apocynaceae family. Defensive proteins with activity against phytophagous insects and phytopathogenic fungi in latex have been described. Latexâs proteic fraction also performs pharmacological activities, such as selective cytotoxic effect in carcinogenic cells. From the proteic fraction effective against neoplastic cells, this work had the goal to identify and further characterize cytotoxic protein(s) biochemically, biologically, and evaluate their biotechnological prospects. Soluble proteins in latex (LP) have been fractioned in ion-exchange matrix, and the fraction capable of cytotoxicity was further fractioned in another ion-exchange matrix (Mono-Q) coupled to a medium-pressure system. P4 was identified as cytotoxic fraction, showing an IC50 of 2.2, 1.2 and 2.9 mg/mL for the cell lines HCT-116, Ovcar-8 and SF-295, respectively. Proteomic analysis of the cytotoxic fraction by two-dimensional electrophoresis allowed 15 spots to be identified, comprising acid proteins (pI among 4 and 6) with 30 kDa apparent molecular weight. All spots were identified as chitinases when evaluated by mass spectrometry, and showed intact mass of 27.4 kDa. The sample reacted positively to the Schiff reagent, suggesting glycosilations. The carbohydrate content was estimated at 12.8%. The amino-terminal sequence obtained (1QPVMNLEYPRYLNDINDYRDDNNYD28) revealed 50% similarity with Solanum lycopersicum, Oryza sativa and Nicotiana tomentosiformes chitinases, among others. The enzymes showed strong chitinolytic activity, with optimal pH varying between 5-6 and optimal temperature of 25 ÂC. The chitinolytic activity was diminished when treated with increasing concentrations of DTT (3, 10 and 30 mM), which suggests the presence of disulfide bonds stabilizing the enzyme. Circular dichroism analyses indicate a larger presence of alpha helices in the structure and that the isoforms has low resistance to pH and temperature variation. High-resolution images generated through atomic force microscopy suggested sample homogeneity and a hexameric configuration. The chitinases did not inhibit mycelial growth of phytopathogenic fungi Fusarium oxysporum and Colletotrichum gloeosporioides, however reduced the germination C. gloeosporioides spores. In consonancy the chitinases did not induce spore oxidative stress, but caused a slight change in membrane permeability of the evaluated spores. Laticifer chitinases (0.1% w/w) showed a strong deleterious effect on the phytophagous insect Callosobruchus maculatus. Effects produced a 57% survival reduction, larval weight reduction (7.8 mg  0.2 / 4.0  0.8), adult insets emergence reduction (50%), in addition to prolonging the mean maturation time from 28 to 33 days. The chitinases (2 mg/Kg, i.v.) showed a strong anti-inflammatory activity, reducing 95% of neutrophil infiltration into the peritoneal cavity in mouse in an inflammation induced by carrageenan assay. L-NAME and Aminoguanidine, two inhibitors of nitric oxide synthase, reversed this effect, possibly indicating involvement of nitric oxide in the effects observed. This action was associated to a reduction of pro-inflammatory cytokines TNF-α and IL-1 levels within the peritoneal cavity and increased serum levels of pro-inflammatory cytokines TNF-α, IL-6 and IL-1. The conclusion is reached that many isoforms of chitinases coexist in C. procera latex. These proteins act possibly in defense against insects, though low action against fungi is shown. Laticifer chitinases were identified as latex proteins cytotoxic on neoplastic cells and they have even been able to modulate pro-inflammatory cytokines levels and nitric oxide in an acute inflammation model. C. procera laticifer chitinases represent interesting molecules for biotechnology prospection in plant defense and pharmacology.
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Prospecção tecnológica a médio e longo prazo sobre o desenvolvimento e aplicações da nanotecnologia em materiais poliméricos / Technological prospection on medium and long term on the development and applications of nanotechnology in polymeric materialsFranchini de Almeida, Carla Carolina Caliani 20 August 2018 (has links)
Orientador: Wagner dos Santos Oliveira / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-20T20:48:08Z (GMT). No. of bitstreams: 1
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Previous issue date: 2012 / Resumo: O desenvolvimento e a aplicação de novas propriedades de materiais e de novos materiais propriamente ditos, tem sido um grande objetivo dos pesquisadores. Estamos em uma etapa do conhecimento científico-tecnológico onde a nanotecnologia, em particular, está se tornando presente em todas as áreas da ciência e da tecnologia. Desta forma, os pesquisadores estão investigando maneiras de recorrerem à nanotecnologia em alta escala, determinando suas características a fim de utilizá-las adequadamente, proporcionando novos tipos de materiais. Uma das áreas de P&D em nanotecnologia, importantes nas atividades acadêmicas e industriais, está voltada para os materiais poliméricos, em nanocompósitos. Este trabalho teve como principal finalidade conhecer como a nanotecnologia se faz presente nos materiais poliméricos, recorrendo aos pesquisadores/especialistas na área, e investigar quais as possibilidades futuras de utilização destes novos materiais junto à sociedade como um todo, por meio da de prospecção tecnológica. Todavia, para uma prospecção adequada, neste caso determinado, é necessário a utilização de ferramentas próprias, para se obter uma resposta cujas possibilidades sejam próximas às reais. Recorreu-se aqui, à Metodologia Delphi, que utiliza conhecimento de especialistas em áreas de específicas, afim de obter dados através de questionários capazes de representar cenários futuros, num âmbito de probabilidades subjetivas, cujas respostas possam ser tratadas por métodos matemáticos / Abstract: The development and the applications of new properties of already known materials and new materials properly said, has been researchers' main objective. We are in a phase of scientific and technological knowledge where the nanotechnology is becoming present in all science and technology fields. Thus, the researchers are investigating ways to resort to the nanotechnology on a large scale, determining its characteristics in order to use them properly, providing new types of materials. One of the R&D fields in nanotechnology is focused on polymeric materials, in nanocomposites, which are present in academic and industrial activities. This study had as main objective to acquire the knowledge of how the nanotechnology is present in polymeric materials, resorting to researchers/ specialists in the field, to know which are the future possibilities of these new materials in the society, as a whole, through technological prospection. However, in order to obtain a prospection of the future in this determined case, it is necessary to use the appropriate tools, in order to obtain an answer which possibilities are close to the real ones. It was used the Delphi Method, which uses the specialists' knowledge in a specific area, in order to obtain data through questionnaires that may represent future scenarios, in an ambit of subjective probabilities, whose answers can be treated by mathematical methods / Mestrado / Ciencia e Tecnologia de Materiais / Mestra em Engenharia Química
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Contribution ergonomique à l’analyse prospective d’innovations technico-organisationnelles dans les systèmes complexes / A human factors contribution to prospective analysis of techno-organizational innovations in complex systemsPalaci, François 04 November 2014 (has links)
La réussite des projets d’introduction d’innovations technico-organisationnelles au sein de systèmes complexes passe par une capacité d’anticipation des conséquences des évolutions programmées. L’ergonomie se saisit de cet enjeu en proposant des démarches méthodologiques visant à approcher l’activité future. Comment décrire, analyser, modéliser l’activité et un futur dispositif, pour les mettre en relation afin d’élaborer des visions de ce que pourrait devenir l’activité ? La question critique est celle de la projection de l’activité dans la situation régie par le futur dispositif. L’examen des démarches existantes montre que les caractéristiques des projets d’innovation et celles des situations concernées peuvent rendre ces démarches difficiles à mettre en œuvre. Une démarche alternative d’analyse prospective des innovations est proposée, qui comprend différentes étapes : caractérisation des dimensions structurantes de l’activité coopérative ; caractérisation des éléments constitutifs du futur dispositif et des grands principes sous-jacents à ces éléments ; mise en relation pour construire une vision des conséquences possibles de l’évolution du dispositif. Cette démarche a été mise à l’épreuve dans le cadre d’un projet d’évolution du dispositif de sécurisation des interventions de maintenance (consignation) dans une industrie de process à risques. Elle a permis de mettre en évidence la centralité des protocoles de coordination, qui forment un « écosystème protocolaire », et le rôle périphérique joué par certains mécanismes, tels que la production d’une conscience mutuelle (mutual awareness) / The success of the implementation of techno-organizational innovations into complex systems requires an ability to anticipate consequences of the intended evolutions. Human Factors take up this issue by putting forward methodological frameworks that aim at foreseeing future work practices. How can actual work practices and a future socio-technical environment be described, analyzed and modeled? How should these accounts be connected in order to envision future work practices? The critical issue is how to make a projection of actual work practices into the future socio-technical environment. An examination of available methodological frameworks shows that they can prove difficult to apply in cases where innovation projects, and the settings those projects deal with, present specific characteristics. An alternative framework to guide prospective analysis of innovations is proposed. Its different stages are: (i) characterizing the structuring dimensions of cooperative work; (ii) characterizing features of the future socio-technical environment and major assumptions underlying those features; (iii) making the connection in order to envision possible consequences of the environment evolutions. This methodological framework was tested in the context of a project that aims at improving the maintenance staff protection (tagout) socio-technical environment in a high-risk process industry. It enabled to highlight the importance of coordinative protocols, which shape an “ecosystem of protocols”, and the peripheral role of some other mechanisms, such as the production of mutual awareness
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Object-Based Image Analysis of Ground-Penetrating Radar Data for Archaic HearthsCornett, Reagan L., Ernenwein, Eileen G. 01 August 2020 (has links)
Object-based image analysis (OBIA) has been increasingly used to identify terrain features of archaeological sites, but only recently to extract subsurface archaeological features from geophysical data. In this study, we use a semi-automated OBIA to identify Archaic (8000-1000 BC) hearths from Ground-Penetrating Radar (GPR) data collected at David Crockett Birthplace State Park in eastern Tennessee in the southeastern United States. The data were preprocessed using GPR-SLICE, Surfer, and Archaeofusion software, and amplitude depth slices were selected that contained anomalies ranging from 0.80 to 1.20 m below surface (BS). Next, the data were segmented within ESRI ArcMap GIS software using a global threshold and, after vectorization, classified using four attributes: area, perimeter, length-to-width ratio, and Circularity Index. The user-defined parameters were based on an excavated Archaic circular hearth found at a depth greater than one meter, which consisted of fire-cracked rock and had a diameter greater than one meter. These observations were in agreement with previous excavations of hearths at the site. Features that had a high probability of being Archaic hearths were further delineated by human interpretation from radargrams and then ground-truthed by auger testing. The semi-automated OBIA successfully predicted 15 probable Archaic hearths at depths ranging from 0.85 to 1.20 m BS. Observable spatial clustering of hearths may indicate episodes of seasonal occupation by small mobile groups during the Archaic Period.
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The Effect of Black-and-White versus Color Imagery on Consumer Behavior: A Construal Level Theory ApproachLee, Hyojin 26 September 2016 (has links)
No description available.
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Amnesia and future thinking: Exploring the role of memory in the quantity and quality of episodic future thoughtsCole, S.N., Morrison, Catriona M., Barak, O., Pauly-Takas, K., Conway, M.A. 21 August 2015 (has links)
Yes / Objectives
To examine the impact of memory accessibility on episodic future thinking.
Design
Single-case study of neurological patient HCM and an age-matched comparison group of neurologically Healthy Controls.
Methods
We administered a full battery of tests assessing general intelligence, memory, and executive functioning. To assess autobiographical memory, the Autobiographical Memory Interview (Kopelman, Wilson, & Baddeley, 1990. The Autobiographical Memory Interview. Bury St. Edmunds, UK: Thames Valley Test Company) was administered. The Past Episodic and Future Episodic sections of Dalla Barba's Confabulation Battery (Dalla Barba, 1993, Cogn. Neuropsychol., 1, 1) and a specifically tailored Mental Time Travel Questionnaire were administered to assess future thinking in HCM and age-matched controls.
Results
HCM presented with a deficit in forming new memories (anterograde amnesia) and recalling events from before the onset of neurological impairment (retrograde amnesia). HCM's autobiographical memory impairments are characterized by a paucity of memories from Recent Life. In comparison with controls, two features of his future thoughts are apparent: Reduced episodic future thinking and outdated content of his episodic future thoughts.
Conclusions
This article suggests neuropsychologists should look beyond popular conceptualizations of the past–future relation in amnesia via focussing on reduced future thinking. Investigating both the quantity and quality of future thoughts produced by amnesic patients may lead to developments in understanding the complex nature of future thinking disorders resulting from memory impairments. / Institute of Psychological Sciences, University of Leeds
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