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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.
11

O s?tio da Figueira/Areal (RS) e seu mapa discursivo : cer?mica arqueol?gica e representa??es maestras de matriz acad?mica e colonial

Milder, Vanessa dos Santos 06 March 2017 (has links)
Submitted by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-06-30T13:07:22Z No. of bitstreams: 1 DIS_VANESSA_DOS_SANTOS_MILDER_COMPLETO.pdf: 4996315 bytes, checksum: 89f99472f2588e28b0603c9818374558 (MD5) / Made available in DSpace on 2017-06-30T13:07:22Z (GMT). No. of bitstreams: 1 DIS_VANESSA_DOS_SANTOS_MILDER_COMPLETO.pdf: 4996315 bytes, checksum: 89f99472f2588e28b0603c9818374558 (MD5) Previous issue date: 2017-03-06 / The purpose is to demonstrate the emerging need to resume archaeological research on the historicity of the established ceramic traditions for the platinum region, already suggested by Jorge Femen?as (1990), which was inhabited by indigenous groups in the past. In order that the data contained in these publications can show us the conceptual path used in the textual engineering of the discourses and the argumentative chain about the archaeological site of Figueira/Areal (Quara?), with the intention of contributing to the understanding of the discursive map built on the researched areas. From the isolation of key concepts one can understand the imbricated framework of statements that make the region and the debate fragile archaeologically. This work will prioritize the notion of representation, be it social or collective, in view of the different issues that permeate the topic addressed, sometimes social representations concerning the struggles of representation between archaeologists and historians, sometimes between collective representation, which falls on the object of the struggles of social representation, the pottery itself, this materialization that is a category of knowledge in historical and archaeological research, coming from human groups of the precolonial period. One of the objectives consisting of to present some discursive constructions of the platinum region and how they interfere in the interpretation of artifacts, in the present, and in the understanding of the archaeological sites. We will take into account the negotiations carried out between the subjects who built the founding discourse concerning the ceramics of the Areal/Quara?-RS site and the stipulation of the Vieira archaeological tradition for this site as a case study, that which aims to reconstruct the discursive map of the pioneer archaeologists through a geography of thought, which also gains support through History and its sources of research. / Objetiva-se demonstrar a emergente necessidade de retomada das pesquisas arqueol?gicas quanto ? historicidade das tradi??es cer?micas estabelecidas para a regi?o platina, j? sugerida por Jorge Femen?as (1990), a qual foi habitada por grupos ind?genas no passado. A pesquisa busca reunir alguns estudos arqueol?gicos j? realizados, afim de que os dados contidos nessas publica??es possam nos mostrar o caminho conceitual utilizado na engenharia textual dos discursos e o encadeamento argumentativo sobre o s?tio arqueol?gico da Figueira/Areal (Quara?), com o intuito de contribuir para o entendimento do mapa discursivo constru?do sobre as ?reas pesquisadas. A partir do isolamento de conceitos chaves pode-se compreender o imbrincado quadro de afirma??es que tornam a regi?o e o debate fragilizados arqueologicamente. Neste trabalho ser? priorizada a no??o de representa??o, seja ela social ou coletiva, tendo em vista as diferentes quest?es que permeiam o tema abordado, ora as representa??es sociais concernentes ?s lutas de representa??o entre os arque?logos e historiadores, ora entre a representa??o coletiva, que recai sobre o objeto das lutas de representa??o social, a cer?mica em si, essa materializa??o que ? uma categoria do conhecimento na pesquisa hist?rica e arqueol?gica, oriunda de grupos humanos do per?odo pr?-colonial. Um dos objetivos consiste em apresentar algumas constru??es discursivas da regi?o platina e como elas interferem na interpreta??o de artefatos, no presente, e na compreens?o dos s?tios arqueol?gicos. Levaremos em considera??o as negocia??es efetuadas entre os sujeitos que constru?ram o discurso fundador concernente ? cer?mica do s?tio Areal/Quara?-RS e a estipula??o da tradi??o arqueol?gica Vieira para este s?tio como um estudo de caso, que objetiva reconstruir o mapa discursivo dos arque?logos pioneiros atrav?s de uma geografia do pensamento, o qual ganha suporte tamb?m atrav?s da Hist?ria e suas fontes de pesquisa.
12

Condi??es macroecon?micas e sa?de

Triaca, L?via Madeira 11 May 2018 (has links)
Submitted by PPG Economia do desenvolvimento (economia-pg@pucrs.br) on 2018-07-20T13:30:59Z No. of bitstreams: 1 LIVIA_MADEIRA_TRIACA_.pdf: 1265885 bytes, checksum: 1cba7091372870441b174ffd4cfd7830 (MD5) / Approved for entry into archive by Sheila Dias (sheila.dias@pucrs.br) on 2018-07-30T11:20:39Z (GMT) No. of bitstreams: 1 LIVIA_MADEIRA_TRIACA_.pdf: 1265885 bytes, checksum: 1cba7091372870441b174ffd4cfd7830 (MD5) / Made available in DSpace on 2018-07-30T11:27:52Z (GMT). No. of bitstreams: 1 LIVIA_MADEIRA_TRIACA_.pdf: 1265885 bytes, checksum: 1cba7091372870441b174ffd4cfd7830 (MD5) Previous issue date: 2018-05-11 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / This thesis consists of three independent essays that seek to analyze the impact of macroeconomic conditions on the health and lifestyle of the Brazilian population. Although they are independent, the three essays are connected. The first essay aims to analyze how the macroeconomic conditions impact the health of Brazilians. To do so, a panel of aggregate data was used at state level in the period 1992-2014 and we used as proxy for macroeconomic conditions the state unemployment rate and for health different mortality rates. Previous studies that addressed this relationship pointed out some flaws in the methodology usually used in the literature, thus, we analyze this relationship through the non-parametric methodology proposed by Li, Chen and Gao (2011), which makes it possible to estimate the trends and variation coefficients in time without assuming the way these functions vary over time. The results observed for Brazil showed that the relationship between macroeconomic conditions and health changes over time. We observed a countercyclical pattern at the beginning of the period, 1992-1995, and procyclical at the end of the period, 2004-2014, for the total mortality rate. We assume that this pattern is following the country?s development. The improvements in the living conditions of the Brazilian population presented in the period 1992-2014 guided the relationship ? ceasing to be countercyclical and making it pro-cyclical as the country develops. The second essay seeks to analyze the impact of macroeconomic conditions on weight measures, such as BMI, overweight, obesity and severe obesity. This essay uses the microdata of VIGITEL in the period from 2006 to 2014 and also uses the state unemployment rate as a proxy for macroeconomic conditions. The results showed that the relationship is robust and presents a procyclical pattern - increases in the unemployment rate reduce BMI, and this reduction is observed throughout the entire distribution, with statistically significant effects for measures of overweight, obesity and severe obesity. We tested two possible ways through which macroeconomic conditions may be affecting BMI, eating habits and practicing physical activities. We observed some evidence that eating habits may be guiding the relationship, but the results are inconclusive. Finally, the third essay analyzes how macroeconomic conditions influence the population's lifestyle. Again, we used VIGITEL data from 2006 to 2014 and the state unemployment rate as a proxy for macroeconomic conditions. For lifestyle we analyzed four groups: smoking, alcohol consumption, sedentary lifestyle and eating habits. This analysis aims to test whether the relationship between macroeconomic conditions and health for Brazil follows one of two hypotheses raised in the literature: hypothesis of variations in lifestyles due to opportunity cost and hypothesis of economic stress. The results found in Brazil suggest that in worse macroeconomic conditions individuals adopt harmful behaviors, such as increased smoking, consumption of fat and soft drinks, but also adopt healthy behaviors, such as reducing the consumption of alcohol and increasing consumption of fruits and vegetables. The majority of the results lead us to believe that the relationship is guided by the hypothesis of "economic stress". However, some conflicting evidence and the unavailability of information about individuals' mental health does not make it possible to validate this hypothesis. / Esta tese ? formada por tr?s ensaios independentes que buscam analisar o impacto das condi??es macroecon?micas na sa?de e no estilo de vida da popula??o brasileira. Apesar de independentes, os tr?s ensaios se relacionam entre si. O primeiro ensaio objetiva analisar como as condi??es macroecon?micas impactam na sa?de dos brasileiros. Para isto, utilizada um painel de dados agregados a n?vel estadual no per?odo de 1992-2014 e usa como proxy para as condi??es macroecon?micas a taxa de desemprego estadual e para a sa?de diferentes taxas de mortalidade. Estudos anteriores que abordaram a rela??o apontaram algumas fragilidades na metodologia usualmente utilizada na literatura, desta forma, propomos analisar a rela??o atrav?s da metodologia n?o param?trica proposta por Li, Chen e Gao (2011) que permite estimar as tend?ncias e os coeficientes de varia??o no tempo sem assumir a forma como essas fun??es variam ao longo do tempo. Os resultados observados para o Brasil mostraram que a rela??o entre condi??es macroecon?micas e sa?de se modifica ao longo do tempo. Observamos um padr?o antic?clico no in?cio do per?odo, 1992-1995 e pr?-c?clico ao final do per?odo, 2004-2014, para a taxa de mortalidade total. Especulamos que este padr?o esteja acompanhando o desenvolvimento do pa?s. As melhorias nas condi??es de vida da popula??o brasileira apresentadas no per?odo de 1992-2014 estariam guiando a rela??o ? deixando-a de ser antic?clica e tornando-a pr?-c?clica a medida que o pa?s vai se desenvolvendo. O segundo ensaio busca analisar o impacto de condi??es macroecon?micas em medidas de peso, como IMC, excesso de peso, obesidade e obesidade severa. Este ensaio utiliza os microdados da VIGITEL no per?odo de 2006 a 2014 e tamb?m utiliza como proxy de condi??es macroecon?micas a taxa de desemprego estadual. Os resultados mostraram que a rela??o ? robusta e apresenta um padr?o pr?-c?clico ? aumentos na taxa de desemprego reduzem o IMC, e esta redu??o ? observada ao longo de toda distribui??o, com efeitos estatisticamente significativos para as medidas de excesso de peso, obesidade e obesidade severa. Testamos dois poss?veis canais pelos quais as condi??es macroecon?micas podem estar afetando o IMC, alimenta??o e pr?tica de atividades f?sicas. Observamos alguns ind?cios de que a alimenta??o pode estar guiando a rela??o, por?m os resultados n?o s?o conclusivos. Por fim, o terceiro ensaio analisa como as condi??es macroecon?micas influenciam o estilo de vida da popula??o. Novamente utilizamos os dados da VIGITEL no per?odo de 2006 a 2014 e a taxa de desemprego estadual como proxy de condi??es macroecon?micas. Para estilos de vida analisamos quatro grupos: tabagismo, consumo de ?lcool, sedentarismo e alimenta??o. Esta an?lise visa testar se a rela??o entre condi??es macroecon?micas e sa?de para Brasil segue uma das duas hip?teses levantadas na literatura: hip?tese de varia??es nos estilos de vida devido ao custo de oportunidade e hip?tese de estresse econ?mico. Os resultados encontrados para o Brasil sugerem que em piores condi??es macroecon?micas os indiv?duos adotam comportamentos nocivos ? sa?de, como o aumento do tabagismo, do consumo de gorduras e refrigerantes, mas tamb?m adotam comportamentos saud?veis, como a redu??o da frequ?ncia de consumo de bebidas alco?licas e o aumento do consumo de frutas e hortali?as. A grande maioria dos resultados nos levam a crer que a rela??o ? guiada pela hip?tese de ?estresse econ?mico?. Por?m, algumas evid?ncias conflitantes e a indisponibilidade de informa??es sobre a sa?de mental dos indiv?duos n?o torna poss?vel validar esta hip?tese.
13

Otimiza????o de t??cnicas de cultivo em biorreator aplicado ?? produ????o do inibidor de tripsina ILTI em Komagataella phaffii (Pichia pastoris)

Carneiro, F??bio Correia 20 February 2018 (has links)
Submitted by Sara Ribeiro (sara.ribeiro@ucb.br) on 2018-04-10T13:05:43Z No. of bitstreams: 1 FabioCorreiaCarneiroDissertacao2018.pdf: 2306587 bytes, checksum: ed2572dbb41a30ee1c54682a411c833d (MD5) / Approved for entry into archive by Sara Ribeiro (sara.ribeiro@ucb.br) on 2018-04-10T13:06:06Z (GMT) No. of bitstreams: 1 FabioCorreiaCarneiroDissertacao2018.pdf: 2306587 bytes, checksum: ed2572dbb41a30ee1c54682a411c833d (MD5) / Made available in DSpace on 2018-04-10T13:06:06Z (GMT). No. of bitstreams: 1 FabioCorreiaCarneiroDissertacao2018.pdf: 2306587 bytes, checksum: ed2572dbb41a30ee1c54682a411c833d (MD5) Previous issue date: 2018-02-20 / Protease inhibitors have a broad biotechnological application, which goes since the development of several drugs to your utilization as a bioinsecticide, antifungal and as an antibacterial agent. However, those are found in small quantities in their natural sources, which unfeasible it utilization in industrial scale. Therefore, the heterologous production ends up as a method that allows the increase of scale production of those proteins. The Inga laurina Trypsin Inhibitor (ILTI) previously characterized showed an inhibitory effect in proteases extracted from the midgut of insects, besides reducing its larval developments by up to 84%, therefore, boing a candidate to be used as a potential bioinsecticide. Thus, the present work aimed at the heterologous production of ILTI in Komagataella phaffii (Pichia pastoris), followed by the optimization of the culture modes in a bioreactor with the objective of maximizing the production of the recombinant protein. For this, the gene that codifies ILTI were cloned in the expression vector pPIC9K, followed by your insertion on the strain GS115 by electroporation. PCR analysis showed that the recombinant vector was integrated into the genome of the yeast, and all the clones obtained had MutS genotype. The expression was performed for 96 hours by adding 0.5% methanol. An analysis of the proteins on the supernatant of the recombinant strain culture, by SDS-PAGE, confirmed the production of a protein with a size close to 20 KDa. Data from MALDI-TOF confirmed that the obtained protein is, in fact, the recombinant ILTI. Furthermore, inhibitory assays showed that the produced protein had activity against trypsin. Thus, culture in bioreactors was performed to optimize the production of this heterologous protein. In order to increase its expression, fed-batch was performed where on the batch phase the biomass production was favored, and the feeding phase was programmed to continuously supply methanol, based on the methanol specific consumption and its specific growth velocity, using methanol as carbon source. During the fermentations, 351.27 UIT were obtained in the extract of crude fermentation broth, and a specific activity of 2.07 UIT/mg protein. Although widely used as a host for the production of heterologous proteins, studies of the production of protease inhibitors in K. phaffii are still very limited. Until the moment, there is no report in the optimization of the production of serine protease inhibitors in K. phaffii, making this study pioneering and essential for the beginning of scaling up the process of this technology. / Os inibidores de protease possuem uma ampla aplica????o biotecnol??gica que vai desde o desenvolvimento de diversos f??rmacos at?? sua utiliza????o como bioinseticidas, antif??ngicos e como agentes antibacterianos. Por??m, estes s??o encontrados em pequenas quantidades nas suas fontes naturais, o que inviabiliza sua utiliza????o em escala industrial. Sendo assim, a produ????o heter??loga acaba sendo um m??todo que permite o aumento da escala de produ????o dessas prote??nas. O inibidor de tripsina de Inga laurina (ILTI) foi caracterizado previamente e mostrou possuir efeito inibit??rio em proteases extra??das do trato digestivo de insetos, al??m de diminuir em at?? 84% seu desenvolvimento larval, sendo, portanto, um candidato a ser utilizado como um poss??vel bioinseticida. Dessa forma, o presente trabalho teve como objetivo a produ????o heter??loga do inibidor ILTI, em Komagataella phaffii (Pichia pastoris), seguido da otimiza????o dos modos de cultivo em biorreator com o objetivo de maximizar a produ????o da prote??na recombinante. Para isso, o gene que codifica o ILTI foi clonado no vetor de express??o pPIC9K seguindo de sua inser????o na cepa GS115 por eletropora????o. An??lises de PCR mostraram que o vetor recombinante foi integrado ao genoma da levedura e que todos os clones obtidos possu??am gen??tipo MutS. A indu????o da express??o foi realizada durante 96 horas por meio da adi????o de metanol ?? 0,5%. A an??lise de prote??nas presentes no sobrenadante da cultura da cepa recombinante, por meio de SDS-PAGE, confirmou a produ????o de uma prote??na com tamanho pr??ximo a 20 KDa. Dados obtidos em MALDI-TOF confirmaram que a prote??na obtida ?? de fato ILTI recombinante. Al??m disso, ensaios inibit??rios mostraram que a prote??na produzida possui atividade contra tripsina. Dessa forma, cultivo em biorreatores foram realizados com a finalidade de otimizar a produ????o dessa prote??na heter??loga. A fim de aumentar sua express??o foram realizadas bateladas alimentadas, onde durante a fase de batelada foi favorecida a produ????o de biomassa, e a fase de alimenta????o programada para fornecer metanol de forma cont??nua, com base nos dados de velocidade espec??fica de consumo de metanol e velocidade de crescimento espec??fica nesta fonte de carbono. Ao longo das fermenta????es realizadas foi obtido 351,27 UIT no extrato bruto do caldo fermentado e uma atividade espec??fica de 2,07 UIT/mg de prote??na. Apesar de ser amplamente utilizada como hospedeira para a produ????o de prote??nas heter??logas, estudos da produ????o de inibidores em K. phaffii ainda s??o muito limitados. At?? o momento n??o existem relatos de otimiza????o da produ????o de inibidores de serinoproteases em K. phaffii, sendo esse estudo pioneiro e essencial para o in??cio do processo de escalonamento dessa tecnologia.
14

Avalia????o de muta????es associadas a resist??ncia a Tigeciclina em isolados cl??nicos de Klebsiella pneumoniae produtoras de Carbapenemase do tipo KPC

Figueiredo, Fernanda Nomiyama 06 March 2018 (has links)
Submitted by Sara Ribeiro (sara.ribeiro@ucb.br) on 2018-04-16T14:40:02Z No. of bitstreams: 1 FernandaNomiyamaFigueiredoDissertacao2018.pdf: 2178476 bytes, checksum: 23f38c14567d00ff189eaef20f904495 (MD5) / Approved for entry into archive by Sara Ribeiro (sara.ribeiro@ucb.br) on 2018-04-16T14:40:47Z (GMT) No. of bitstreams: 1 FernandaNomiyamaFigueiredoDissertacao2018.pdf: 2178476 bytes, checksum: 23f38c14567d00ff189eaef20f904495 (MD5) / Made available in DSpace on 2018-04-16T14:40:47Z (GMT). No. of bitstreams: 1 FernandaNomiyamaFigueiredoDissertacao2018.pdf: 2178476 bytes, checksum: 23f38c14567d00ff189eaef20f904495 (MD5) Previous issue date: 2018-03-06 / Klebsiella pneumoniae is one of the main bacterial agents that may cause infections related to health care assistance. K. pneumoniae frequently carries the resistance gene K. pneumoniae carbapenemase (KPC). Currently, tigecycline can be considered one of the last therapeutic options for KPC, but reports of tigecycline-resistant KPC isolates are on the rise, being indicated as most common mechanism the increased AcrAB-TolC efflux pump system expression. However, molecular tigecycline resistance mechanisms associated to AcrAB-TolC still remains obscure. Thus, the main goal of this study was to verify if tigecycline resistance can be related to the presence of mutations in the regulatory genes of AcrAB-TolC, AcrR and RamR. Therefore, 32 K. pneumoniae isolates were used, identification and antibiogram performed using Vitek 2 systems. The minimum inhibitory concentrations were confirmed using E-test. Primers were designed in order to verify mutations within AcrR and RamR genes. PCR analysis showed that the mutations found within these genes were transversions (94% for AcrR and 90% for RamR) and transitions (6% for AcrR and 10% for RamR). Nevertheless among the mutations, no distinction between tigecycline susceptible and resistant isolates was found. Some of the transversions caused change in the amino acid encoding 6 in AcrR and 15 in RamR. Presence of these types of mutations evaluation can be seen as the first bacterial resistance study step, as it may be caused by oxidative damage for bacterial DNA, frequently caused by antibiotic selective pressure. Tigecycline resistance found in this study`s clinical isolates may be associated to alterations in another genes that can trigger mechanisms associated to this antibiotic. / Klebsiella pneumoniae consiste em um dos principais agentes bacterianos causadores de infec????es relacionadas ?? assist??ncia ?? sa??de (IRAS). K. pneumoniae carrega frequentemente o gene de resist??ncia K. pneumoniae carbapenemase (KPC). Atualmente, a tigeciclina pode ser considerada uma das ??ltimas op????es terap??uticas para KPC, mas os relatos de isolados de KPC resistentes a tigecilina est??o em ascens??o, sendo a hiperexpress??o da bomba de efluxo AcrAB-TolC indicado como mecanismo mais comum. No entanto, os mecanismos moleculares de resist??ncia ?? tigeciclina associada ao AcrAB-TolC permanecem obscuros. Desta forma o objetivo deste trabalho foi verificar se a resist??ncia a tigeciclina pode estar relacionada ?? presen??a de muta????es nos genes ArcR e RamR, reguladores de AcrAB-TolC. Para tanto, 32 isolados de K. pneumoniae foram utilizados, sendo a identifica????o e o antibiograma feitos utilizando o sistema Vitek 2. A confirma????o das concentra????es inibit??rias m??nimas (CIMs) foram realizadas por E-test. Iniciadores foram desenhados para verifica????o de muta????es nos genes (AcrR e RamR). As an??lises por PCR mostraram que as muta????es encontradas nos genes AcrR e RamR foram substitui????es por transvers??o (94% e 90% para AcrR e RamR respectivamente) e transi????o (6% e 10% para AcrR e RamR respectivamente), por??m n??o foi identificada distin????o da presen??a de muta????es entre isolados sens??veis e resistentes a tigeciclina. Algumas tranvers??es ocasionaram mudan??a na codifica????o do amino??cido, sendo 6 em AcrR e 15 em RamR. A avalia????o da presen??a desses tipos de muta????es consiste em um primeiro passo para o estudo da resist??ncia bacteriana, j?? que pode ser causada por dano oxidativo ao DNA bacteriano, frequentemente ocasionado por press??o seletiva dos antibi??ticos. A resist??ncia a tigeciclina encontrada nos isolados cl??nicos do presente estudo, provavelmente pode estar associada a altera????es em outros genes desencadeadores de mecanismos de resist??ncia a tigeciclina.
15

An??lise molecular dos impactos do cultivo de dendezeiros e do amarelecimento fatal sobre as comunidades de arqueias de solo amaz??nico

Tupinamb??, Daiva Domenech 12 March 2015 (has links)
Submitted by Kelson Anthony de Menezes (kelson@ucb.br) on 2016-11-23T11:36:50Z No. of bitstreams: 1 DaivaDomenechTupinambaDissertacao2015.pdf: 12204296 bytes, checksum: db4048c47ac3f9f47171655f6bfb3e91 (MD5) / Made available in DSpace on 2016-11-23T11:36:50Z (GMT). No. of bitstreams: 1 DaivaDomenechTupinambaDissertacao2015.pdf: 12204296 bytes, checksum: db4048c47ac3f9f47171655f6bfb3e91 (MD5) Previous issue date: 2015-03-12 / The Amazon rainforest is home to huge diversity of macro-species. However, little is known about the microbial diversity. The effect of land-use after deforestation is of great importance in the development of public policies. The metagenome were extracted from soils of native forest and an adjacent cultivated area with oil palm and pyrosequencing of 16S rRNA genes of archaea communities present in those soils was used for phylogenetic characterization of the archaeal microbiota, in an unprecedented characterization of native Amazonian soil and soils cultivated with oil palm. All OTUs of the native forest soils and cultivated area with oil palm were classified into two phyla: Euryarchaeota and Thaumarchaeota. Thaumarchaeota phylum was predominant only in native forest. Euryarchaeota, especially methanogenic archaea, were prevalent in cultivated area with oil palm. Various genera involved in biogeochemical cycles, as AOA and methanogenic archaea, were identified in all samples. In native forest the genera with larger representation were Candidatus Nitrosotalea and Candidatus Nitrososphaera, AOAs. In the cultivated area with oil palm the genus with larger representation was Rice Cluster I. There is a direct correlation between levels of organic matter and total carbon and the diversity of archaea in Amazonian soils. In addition, anthropization also showed impact on this diversity. This is the first study to characterize the microbiota of archaea in Amazonian soils using specific primers and high-throughput sequencing. This work also characterize the archaeal communities in soils cultivated with oil palm with and without symptoms of Fatal Yellowing. The growth of world energy demand and concern with climate changes lead to a worldwide increase in the search for alternative sources of energy. Within this scenario, agroenergy presents itself as a viable alternative. However, there are still several limitations to the production of biofuels, such as efficiency and cost of the production process as well as the quality of the energy feedstock available. Palm oil is one of the most promising sources of oil for biodiesel production in Brazil, and the Fatal Yellowing (FY), a disease with unknown etiology, is limiting the use of palm. From the metagenome extracted from soils associated to oil palms with and without symptoms of FY was used pyrosequencing of 16S rRNA genes of archaeal communities for phylogenetic characterization, in an attempt of an association of some microorganism with FY, and an unprecedented characterization of soils cultivated with oil palms with and without FY. In the comparison among oil palms with and without FY symptoms, the three groups were different among then; group 8 showed higher diversity and had lower coverage. All groups presented two phyla: Thaumarchaeota and Euryarchaeota. There was prevalence of the second in all groups, with an increase in abundance of methanogenic archaea with FY. In the analysis of genera, significant differences between the groups were observed, especially for genera Rice Cluster I and Ca. Nitrosotalea, which showed an increase in abundance directly proportional to the increase of the FY symptoms. The genera Ca. Nitrososphera and Methanocella showed the opposite; a decrease in abundance with the increase of FY symptoms. However, it???s not possible to say that these genera are related to FY. This work is complementary to the study of bacterial microbiota of these soils, already performed; and the study of fungal microbiota, in progress. This is an unpublished study, which will contribute to future studies on the Fatal Yellowing. / A floresta Amaz??nica ?? ber??o de enorme diversidade de macroesp??cies. Entretanto, pouco se sabe sobre a diversidade microbiana. O efeito do uso da terra ap??s o desmatamento das florestas ?? de grande import??ncia no desenvolvimento de pol??ticas p??blicas. A partir do metagenoma extra??do do solo de mata nativa Amaz??nica e de uma ??rea adjacente cultivada com dendezeiros foi utilizado o pirosequenciamento do 16S rRNA das comunidades de arqueias presentes nesses solos para caracteriza????o filogen??tica e an??lise comparativa das comunidades de arqueias. Todas as OTUs dos solos de mata nativa e ??rea cultivada com dendezeiros foram classificadas em apenas dois filos: Euryarchaeota e Thaumarchaeota. O filo Thaumarchaeota foi predominante apenas na mata nativa, sendo Euryarchaeota, especialmente arqueias metanog??nicas, predominantes nos solos cultivados com dendezeiros. Diversos g??neros envolvidos com os ciclos biogeoqu??micos, como arqueias oxidadoras de am??nia e metanog??nicas, foram identificados nas duas amostras. Na mata nativa os g??neros classificados que apresentam a maior representa????o foram Candidatus Nitrosotalea e Candidatus Nitrososphaera, AOAs. J?? na ??rea cultivada com dendezeiros o g??nero de maior representa????o foi Rice Cluster I. Foi encontrada um correla????o direta entre os n??veis de mat??ria org??nica e carbono total e a diversidade de arqueias nos solos amaz??nicos. Al??m disso, a antropiza????o tamb??m apresentou impacto sobre essa diversidade. Este ?? o primeiro estudo de caracteriza????o da microbiota de arqueias em solos amaz??nicos usando primers espec??ficos e sequenciamento de alto desempenho. Este trabalho tamb??m caracterizou as comunidades de arqueias em solos cultivados com dendezeiros com e sem sintomas de Amarelecimento Fatal. O crescimento da demanda energ??tica mundial e preocupa????o com as mudan??as clim??ticas levou a um aumento da busca mundial por fontes alternativas de energia, o que est?? levando diversos pa??ses a buscarem na bioenergia uma alternativa. Entretanto, ainda existem diversas limita????es na produ????o de biocombust??veis, seja na efici??ncia e custo do processo produtivo, seja na qualidade das fontes energ??ticas dispon??veis. O dend?? ?? uma das fontes mais promissoras de ??leo para a produ????o de biodiesel no Brasil, sendo o Amarelecimento Fatal, doen??a com fator etiol??gico desconhecido, um limitante no uso do dend??. A partir do metagenoma extra??do dos solos associados a dendezeiros com e sem sintomas de AF foi utilizado o pirosequenciamento do 16S rRNA das comunidades de arqueias para caracteriza????o filogen??tica. Foi realizada uma an??lise comparativa das comunidades de arqueias de solos de dendezeiros com e sem sintomas de AF, numa tentativa de associa????o de algum microrganismo com essa doen??a. Na compara????o entre dendezeiros com e sem sintomas de AF, os tr??s grupos estudados diferiram entre si; o grupo 8 apresentou maior diversidade e obteve menor cobertura. Todos os grupos apresentaram dois filos: Thaumarchaeota e Euryarchaeota. Houve preval??ncia do segundo em todos os grupos, com aumento na abund??ncia de arqueias metanog??nicas com o AF. Na an??lise entre g??neros, foram observadas diferen??as significativas entre os grupos, especialmente para os g??neros Rice Cluster I e Ca. Nitrosotalea, que apresentaram um aumento em suas abund??ncias diretamente proporcional ao aumento dos sintomas do AF. Os g??neros Ca. Nitrososphaera e Methanocella apresentaram uma rela????o inversa; uma queda na abund??ncia com o aumento dos sintomas do AF. Entretanto, n??o se pode afirmar que estes grupos est??o relacionados ao AF. Este trabalho ?? complementar ao estudo da microbiota bacteriana desses solos, j?? realizado; e pelo estudo da microbiota f??ngica, em andamento. Trata-se de um estudo in??dito, que ir?? contribuir para os estudos futuros sobre o Amarelecimento Fatal.
16

Etude expérimentale et spectroscopique de la cristallochimie du manganèse dans les silicates hydroxylés

Papin, Arnaud 05 December 2001 (has links) (PDF)
Cette étude porte sur la cristallochimie du manganèse dans les silicates ferromagnésiens, clino-amphiboles et phyllosilicates 2:1, abordée par voie expérimentale en milieu hydrothermal, sous différentes conditions de température, de pression, et de fugacité d'oxygène qui conditionnent ses états de valence. La caractérisation des phases et assemblages obtenus a été réalisée par diffraction des rayons X, microsonde électronique, microscopie électronique à balayage, absorption optique, analyses thermogravimétriques, spectrométries infrarouge et Raman, et spectrométrie d'absorption X (EXAFS).<br /><br />Le manganèse, qui possède plusieurs états de valence, se traduisant par des valeurs de rayon ionique variées, est susceptible d'occuper différents sites dans les silicates ferromagnésiens, comme dans les oxydes et bien d'autres composés.<br /><br /> Dans les clino-amphiboles, de type trémolite, et de type richtérite prise comme modèle des clino-amphiboles sodi-calciques, comme dans les phyllosilicates 2:1, talc, phlogopite et clintonite, l'importance des contraintes stériques sur la capacité d'incorporation du manganèse et sa possible distribution dans les différents sites des structures concernées a été démontrée. La multiplicité des sites aptes à accueillir le manganèse permet sa distribution sur l'ensemble des sites octaédriques M1,2,3 et antiprisme pseudo-cubique M4 des clino-amphiboles, comme des phyllosilicates 2:1 en sites M1 et M2 et potentiellement en position interfoliaire. <br /><br /> Cette étude montre que le manganèse divalent peut effectivement se distribuer sur l'ensemble des sites M dans la manganocummingtonite, équivalent manganifère de la trémolite. Dans les clino-amphiboles de type richtérite, synthétisées en conditions oxydantes, la présence du manganèse en sites octaédriques M1,2,3 provoque un changement d'état de valence 2+ ® 3+, qui entraîne une non-protonation locale voire totale de l'amphibole, comme dans la ungarettiite, NaNa2( )Si8O22O2, décrite dans le milieu naturel, et dont les conditions de stabilité ont été déterminées au cours de ce travail.<br /><br />De même, dans les phyllosilicates, on montre la possibilité d'occupation de différents sites par Mn2+, les sites M, mais aussi le site interfoliaire dans la clintonite. Dans le talc, le remplacement de Mg2+ par Mn2+ est restreint à moins de 20%, pour des raisons d'adaptation dimensionnelle entre couches tétra- et octaédriques. Par contre, la souplesse structurale des micas permet une incorporation plus élevée de Mn2+. L'association du manganèse divalent avec des éléments de plus faible taille, tels que l'aluminium, le magnésium ou le zinc, dans les micas de type phlogopite, permet, pour des raisons stériques, de stabiliser leur structure. En conditions oxydantes, Mn3+, de plus faible rayon ionique que Mn2+, contribue aussi à cette adaptation, comme dans la norrishite, K( Li)Si4O12, ce qui entraîne, comme dans les amphiboles, une non-protonation.
17

Estruturas cer?micas a base de zirc?nia e alumina utilizadas na confec??o de infra - estruturas para coroas e pontes fixas

Silva, Cl?udia Angl?lica Melo da 29 March 2010 (has links)
Made available in DSpace on 2014-12-17T14:06:54Z (GMT). No. of bitstreams: 1 ClaudiaAMS_DISSERT.pdf: 2577371 bytes, checksum: 741bbb91aaccd5dd4b233f1b8017a831 (MD5) Previous issue date: 2010-03-29 / The continuous advances in ceramic systems for crowns and bridges infrastructure getting researchers and manufacturers looking for a material that has good mechanical properties and aesthetic. The purpose of this study was to verify in which composition and sintering temperature the ceramic system for infrastructure composed of alumina and zirconia would have the best mechanical properties. With this objective we made in UFRN laboratories 45 test bodies in the form of rectangular bars with the following dimensions: 30mm x 8mm x 3mm, where we separated by the sintering temperature: 1200?C, 1300?C and 1400?C, and by comp osition: 33% Zirconia + 67% Alumina; 50% Zirconia + 50% Alumina and 25% Zirconia + 75% Alumina, these test bodies were not infiltrated with glass. Also, were made nine test bodies by a technical from a laboratory with a commercial ceramic system: in the Ceram Zirc?nia (Vita - Zahnfabrik) with the following dimensions: 20mm x 10mm x 0.5mm, these test bodies following all recommendations of the manufacturer and were infiltrated with glass. Were realized optical and electronic microscopy analyses, hardness testing, resistance to bending in three points, porosity and bulk density. After analysis of the results we verified that with the increasing of sintering temperature, increased the value of resistance to bending, but with the same temperature there was no significant difference between the different compositions, samples made with the commercial ceramic that were infiltrated, presented a resistance to bending six times greater than the samples sintered to 1400?C and which have not been infiltra ted. There was no significant difference between the values of apparent porosity for the samples made in UFRN laboratories, but the samples of commercial ceramic obtained 0% in porosity apparent value. In tests of Rockwell Hardness there is an increase in the value of Hardness, with the increase of sintering temperature for the samples not infiltrated. Samples infiltrated showed similar values as the samples sintered in 1400?C. There was no significant difference between the values of apparent density among samples manufactured in UFRN laboratories and samples made with a commercial ceramic / Os avan?os constantes dos sistemas cer?micos para infra-estruturas de coroas e pontes fazem com que os pesquisadores e fabricantes busquem um material que tenha boas propriedades mec?nicas e est?ticas. O intuito deste trabalho foi verificar em qual composi??o e temperatura de sinteriza??o o sistema cer?mico a base de alumina e zirc?nia para infra-estrutura teria as melhores propriedades mec?nicas. Com este objetivo confeccionamos nos laborat?rios da UFRN 45 corpos-e-prova em forma de barras retangulares com as seguintes dimens?es: 30mm x 8mm x 3mm, onde os separamos por temperatura de sinteriza??o: 1200?C, 1300?C e 1400?C; e por composi??o: 33% Zirc?nia + 67% Alumina; 50% Zirc?nia + 50% Alumina e 25% Zirc?nia + 75% Alumina, estes corpos-de-prova n?o foram infiltrados com vidro. Foram confeccionados ainda nove corpos- e-prova por um t?cnico de laborat?rio com um sistema cer?mico comercial o In Ceram Zirc?nia (Vita Zahnfabrik) com as seguintes dimens?es: 20mm x 10mm x 0,5mm, estes corpos-de-prova seguiram todas as recomenda??es do fabricante e foram infiltrados com vidro. Foram realizadas an?lises por microscopia ?tica e eletr?nica, ensaios de dureza, de resist?ncia ? flex?o em tr?s pontos, porosidade e densidade aparente. Ap?s a an?lise dos resultados verificamos que com o aumento da temperatura de sinteriza??o, aumentamos o valor da resist?ncia ? flex?o, sendo que dentro da mesma temperatura n?o houve diferen?a significante entre as diferentes composi??es, as amostras confeccionadas com a cer?mica comercial e que foram infiltradas apresentaram uma resist?ncia ? flex?o seis vezes maior que as amostras sinterizadas ? 1400?C e que n?o foram infiltradas. N?o houve diferen?a significante entre os valores da porosidade aparente para as amostras confeccionadas nos laborat?rios da UFRN, j? as amostras da cer?mica comercial obtiveram um valor de 0% de porosidade aparente. Nos ensaios de Dureza Rockwell verifica-se um aumento no valor da Dureza, com o aumento da temperatura de sinteriza??o das amostras n?o infiltradas. As amostras infiltradas apresentaram valores similares aos das amostras sinterizadas ? 1400?C. N?o houve diferen?a significante entre os valores de densidade aparente entre as amostras confeccionadas nos laborat?rios da UFRN e as amostras confeccionadas com a cer?mica comercial
18

S?ntese e caracteriza??o de cer?micas nanom?tricas para produ??o de g?s de s?ntese

Oliveira, Rosane Maria Pessoa Bet?nio 04 October 2010 (has links)
Made available in DSpace on 2014-12-17T14:07:04Z (GMT). No. of bitstreams: 1 RosaneMPBO_TESE_partes_autorizadas.pdf: 623811 bytes, checksum: 3724885447cd319f325ecaa9845943f0 (MD5) Previous issue date: 2010-10-04 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / In this work, ceramic powders belonging to the system Nd2-xSrxNiO4 (x = 0, 0.4, 0.8, 1.2 and 1.6) were synthesized for their use as catalysts to syngas production partial. It was used a synthesis route, relatively new, which makes use of gelatin as organic precursor. The powders were analyzed at several temperatures in order to obtain the perovskite phase and characterized by several techniques such as thermal analysis, X-rays diffraction, Rietveld refinement method, specific surface area, scanning electron microscopy, energy dispersive spectroscopy of X-rays and temperature programmed reduction. The results obtained using these techniques confirmed the feasibility of the synthesis method employed to obtain nanosized particles. The powders were tested in differential catalytic conditions for dry reforming of methane (DRM) and partial oxidation of methane (POM), then, some systems were chosen for catalytic integrals test for (POM) indicating that the system Nd2-xSrxNiO4 for x = 0, 0.4 and 1.2 calcined at 900 ?C exhibit catalytic activity on the investigated experimental conditions in this work without showing signs of deactivation / Neste trabalho, p?s cer?micos pertencentes ao sistema Nd2-xSrxNiO4 (x = 0; 0,4; 0,8; 1,2 e 1,6) foram sintetizados visando sua utiliza??o como catalisadores para produ??o de g?s de s?ntese. Foi utilizada uma rota de s?ntese, relativamente nova, na qual faz uso de gelatina como precursor org?nico. Os p?s cer?micos sintetizados foram calcinados a v?rias temperaturas visando ? obten??o da fase perovsquita e ent?o caracterizados por v?rias t?cnicas, tais como: An?lise t?rmogravim?trica, difra??o de raios X, refinamento Rietveld, ?rea espec?fica (m?todo BET), microscopia eletr?nica de varredura, espectroscopia por dispers?o de energia de raios X e redu??o ? temperatura programada. Os resultados obtidos atrav?s destas t?cnicas confirmaram a viabilidade do m?todo de s?ntese empregado para obten??o de part?culas nanom?tricas. Os p?s foram submetidos a testes catal?ticos em condi??es diferenciais para rea??o de reforma a seco (RSM) e oxida??o parcial do metano (OPM), em seguida alguns sistemas foram escolhidos para testes catal?ticos integrais de OPM indicando que o sistema Nd2-xSrxNiO4 para x = 0, 0,4 e 1,2 calcinados a 900 ?C apresentam atividade catal?tica nas condi??es experimentais investigadas nesse trabalho sem mostrar sinais de desativa??o
19

Efeito de fontes e doses de ?cidos h?micos na produ??o do feij?o (Phaseolus vulgaris L.) / Effects of sources and doses of humic acids in bean production (Phaseolus vulgaris L.)

Barral, Uidemar Morais January 2015 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2016-01-05T13:42:22Z No. of bitstreams: 2 uidemar_morais_barral.pdf: 1274629 bytes, checksum: d89bbca6115310a0b5ad8323167ba551 (MD5) license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2016-01-05T18:01:03Z (GMT) No. of bitstreams: 2 uidemar_morais_barral.pdf: 1274629 bytes, checksum: d89bbca6115310a0b5ad8323167ba551 (MD5) license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) / Made available in DSpace on 2016-01-05T18:01:03Z (GMT). No. of bitstreams: 2 uidemar_morais_barral.pdf: 1274629 bytes, checksum: d89bbca6115310a0b5ad8323167ba551 (MD5) license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) Previous issue date: 2015 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (Capes) / A mat?ria org?nica (MOS) do solo consiste de uma mistura de compostos em v?rios est?gios de decomposi??o, resultante da degrada??o biol?gica de res?duos de plantas e animais, e da atividade de microrganismos, denominados subst?ncias h?micas (SHs). Essas subst?ncias fracionadas em ?cidos f?lvicos (AF), ?cidos h?micos (AH) e humina (H), de acordo com sua solubilidade em meio ?cido ou b?sico. Os AH t?m sido usados como fertilizantes aplicados diretamente no solo ou via foliar, principalmente por influenciarem o metabolismo das plantas. Objetivou-se com este trabalho avaliar em feijoeiro (Phaseolus vulgaris L.), a influ?ncia de fontes e doses diferentes de AH, na produ??o, crescimento radicular e absor??o de nutrientes e biodisponibilidade de nutrientes no solo. O experimento foi conduzido utilizando o delineamento em blocos casualizados com 15 tratamentos, sendo estes as fontes de AH (turfa - 1, composto - 2 e produto comercial - 3) e as doses de AH (0, 2, 8, 16 e 32 kg ha-1), com quatro repeti??es. Foram avaliadas: altura das plantas (cm), di?metro do caule (cm), teor de clorofila (?g cm-2) e teor de macro e micronutrientes nas folhas no florescimento do feijoeiro e ao fim do experimento, peso de sementes (g), massa seca da parte a?rea e de ra?zes (g), n?mero de vagem por planta e de sementes por vagem e no solo: pH em ?gua e teores de mat?ria org?nica, P, K, Ca, Mg, Al e H+Al. A aplica??o de AH reduziu o crescimento e produ??o de gr?o, com aumento das doses em cada fonte, seguindo a ordem fonte 3 > fonte 1 > fonte 2. Os teores de P, K, Cu, Fe, Mn e Zn nas folhas foram influenciados pelas doses de todas as fontes de AH. Houve redu??o para maioria dos nutrientes quantificados nas folhas com aumento das doses de AH. Os teores de P e K se elevaram no solo, com a aplica??o de AH. Para condi??es testadas, n?o se recomenda utiliza??o de AH para cultura do feijoeiro. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Produ??o Vegetal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2015. / ABSTRACT The soil organic matter (SOM) consists of a mixture of compounds in many decomposition stages, the result of biological degradation of residues of plants and animals, and microorganisms activity, called humic substances (HS). These substances are fractionated into fulvic acids (FA), humic acids (HA) and humin (H), according to their solubility in acidic or basic medium. HA have been used as fertilizers directly applied to the soil or via foliar, mainly because they influence plants metabolism. The main goal of this study was evaluating, in bean plant (Phaseolus vulgaris L.), the influence of sources and different doses of HA in production, root growth, nutrients absorption and bioavailability of nutrients in the soil. The experiment was conducted using randomized block design with 15 treatments, which are the sources of HA (peat ? 1, compound ? 2 and commercial product ? 3) and doses of HA (0, 2, 8, 16 e 32 kg ha-1), with four repetitions. Evaluations were made on: plants height (cm), stem diameter (cm), chlorophyll content (?g cm-2) and content of macro and micronutrients in the leaves in the flowering stages and in the end of the experiment, seeds weight (g), dry matter of the aerial part and roots (g), number of pods per plant and seeds per pod, and in the soil: pH in water and contents of organic matter, P, K, Ca, Mg, Al and H+Al. Application of HA reduced bean growth and production, with increase of doses in each source, following order: source 3 > source 1 > source 2. Contents of P, K, Cu, Fe, Mn and Zn in the leaves were influenced by the doses of all HA sources. Most of the nutrients quantified in the leaves were reduced with increasing HA doses. Contents of P and K were increased in the soil with application of HA. For tested conditions, the use of HA for bean culture is not recommended.
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Otimiza??o dos par?metros de eletropolimeriza??o do ?cido 4-hidroxifenilac?tico para utiliza??o no desenvolvimento de genossensores aplicados na detec??o de Mycobacterium tuberculosis

Corr?a, Ricardo Augusto Moreira de Souza 05 February 2015 (has links)
?rea de concentra??o: Qu?mica Anal?tica. / Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2016-01-06T19:01:54Z No. of bitstreams: 2 license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) ricardo_augusto_m_souza_correa.pdf: 3203874 bytes, checksum: 613643e6fe67082b3f47a7d8e0528aaf (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2016-01-07T11:53:33Z (GMT) No. of bitstreams: 2 license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) ricardo_augusto_m_souza_correa.pdf: 3203874 bytes, checksum: 613643e6fe67082b3f47a7d8e0528aaf (MD5) / Made available in DSpace on 2016-01-07T11:53:33Z (GMT). No. of bitstreams: 2 license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) ricardo_augusto_m_souza_correa.pdf: 3203874 bytes, checksum: 613643e6fe67082b3f47a7d8e0528aaf (MD5) Previous issue date: 2015 / Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG) / Foi otimizada a eletropolimeriza??o do ?cido 4-hidroxifenilac?tico (4-HFA), visando sua aplica??o como plataforma funcionalizada para imobiliza??o de biomol?culas, para o desenvolvimento de genossensores. Foi utilizado o mon?mero 4-HFA, e por meio deste a eletrogera??o foi conduzida sobre a superf?cie do eletrodo de grafite (EG), utilizando-se a t?cnica de voltametria c?clica na faixa de +0,0 a +1,20 V, onde foram investigados dois par?metros: n?mero de ciclos de potencial aplicado e velocidade de varredura utilizada. Associado a este estudo, foi investigado a imobiliza??o de pequenos fragmentos de DNA (oligonucleot?deos), observando a atua??o da plataforma funcionalizada na resposta do biossensor para detec??o dos oligonucleot?deos, bem como avalia??o do reconhecimento do evento de hibridiza??o com o alvo complementar. Observou-se que o filme polim?rico formado apresentou um par redox na regi?o +0,53/+0,38 V e o aumento do n?mero de ciclos gera plataformas mais eletroativas devido a maior quantidade de material adsorvido, por outro lado, a diminui??o da velocidade de varredura gera plataformas mais eletroativas devido a ocorr?ncia do acoplamento mais organizado. Medidas de espectroscopia de imped?ncia eletroqu?mica (EIE) mostraram maior resist?ncia do filme para os eletrodos modificados com maior n?mero de ciclos, bem como para os eletrodos modificados com maiores velocidades de varredura. Imagens de microscopia eletr?nica de varredura (MEV) mostraram que em todos os casos n?o h? total recobrimento da superf?cie do EG e corroboraram com os demais resultados encontrados. As imagens de MEV demonstraram que diferentes ciclagens n?o influenciam na morfologia do filme formado, mas sim na quantidade de material adsorvido. Por outro lado, as imagens tamb?m mostraram que as diferentes velocidades de varredura geram filmes com morfologias distintas. A plataforma EG/poli(4-HFA) mostrou-se eficiente e sens?vel para a imobiliza??o de oligonucleot?deos, bem como para o evento de hibridiza??o com o oligonucleot?deo complementar. O eletrodo que apresentou as melhores respostas para imobiliza??o das ssDNAs estudadas e detec??o dos respectivos alvos complementares foi o eletrodo modificado com 100 ciclos de potencial na velocidade de varredura de 75 mV/s, uma vez que mostrou maiores amplitudes nos valores de corrente de pico. A constru??o do genossensor para detec??o do bacilo Mycobacterium tuberculosis confirmou os demais resultados acerca da efici?ncia da plataforma EG/poli(4-HFA), uma vez que a mesma demonstrou excelente sensibilidade ao utilizar o Azul de Metileno (AM) como intercalador. O genossensor desenvolvido apresentou um excelente limite de detec??o de 0,16 nmol, operando com volumes baix?ssimos de solu??o, sendo estes 15 ?L de sonda MYC e 10 ?L de alvo MYC. Foi poss?vel desenvolver o dispositivo e ainda otimizar v?rios par?metros de adsor??o da sonda e hibridiza??o do alvo, o que ocasionou uma melhoria da diminui??o do sinal de redu??o do AM de 14% para 34%. Em adi??o, estudos com o interferente MYC-NE demonstraram que o genossensor possui seletividade satisfat?ria, uma vez que a hibridiza??o com o interferente acarretou em diminui??o do sinal 46% inferior quando comparado ao alvo espec?fico. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Qu?mica, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2015. / ABSTRACT Aiming its application as functionalized platform for biomolecules immobilization, it was optimized the electropolymerization of 4-hydroxyphenylacetic acid (4-HPA), for genosensors development. The monomer 4-HPA was used and, by means of it the electrogeneration was carried out on the surface of the graphite electrode (GE), using cyclic voltammetry on the range of +0,0 to +1,20 V, in which were investigated two parameters: number of cycles of applied potential and scan rate used. Associated to this work it was investigated small DNA fragments (oligonucleotides), observing the performance of the functionalized platform in biosensor response to detection of oligonucleotides, as well as evaluation hybridization event recognition with the complementary target. It was observed that the polymeric film showed a redox couple in region +0,53/+0,38 V and an increase of the number of cycles produces more electroactive platforms due to greater amount of adsorbed material. On the other hand, a decrease in scan rate produces more electroactive platforms due to the occurrence of more organized coupling. Electrochemical Impedance Spectroscopy (EIS) measurements showed higher film resistance to the modified electrodes with more number of cycles, as well as for the modified electrode with higher scan rate. Images of scanning electron microscopy (SEM) have shown that in all cases there is no complete coverage of the GE surface and corroborated with the other results found. SEM images have shown that the number of cycles does not influence the morphology of the formed film, but the amount of the adsorbed material. On the other hand, images also have shown that different scan rates produce films with distinct morphologies. GE/poly(4-HPA) platform have shown to be sensitive and efficient to oligonucleotide immobilization, as well as for hybridization event with the complementary oligonucleotide. The electrode that showed the best responses to the immolization of the studied ssDNA and the respective complementary target detection was the electrode modified with 100 potential cycles in the scan rate of 75 mV/s since it has shown higher amplitudes at peak current values. Genosensor construction for Mycobacterium tuberculosis bacillus detection confirmed the results about the GE/poly(4-HPA) platform efficiency, since it has shown excellent sensitivity when using Methilene Blue (MB) as intercalator. The designed biosensor has shown an excellent limit detection of 0,16 nmol, operating with very low solution volumes these being 15 ?L of MYC probe and 10 ?L MYC target. It was possible develop the device and even optimize several probe adsorption parameters and target hybridization which led to an improvement in decrease of the MB reduction signal from 14% to 34%. In addition, studies with the interfering MYC-NE has shown that the genosensor has satisfactory selectivity since the hybridization with the interfering resulted in a signal decrease 46% lower when compared to the specific target.

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