L'objet de cette thèse est la construction d'un dispositif expérimental, et en particulier d'un laser continu, accordable à 205nm, pour la mesure du déplacement de Lamb du niveau fondamental de l'atome d'hydrogène. le chapitre 1 du mémoire présente le déplacement de Lamb d'un point de vue historique, et l'intérêt que présente sa mesure, tant pour la métrologie que pour tester l'électrodynamique quantique. Le chapitre 2 est consacré à un résumé de la théorie de l'atome d'hydrogène. Le principe de l'expérience repose sur la comparaison de deux fréquences qui sont dans un rapport quatre : celles des transitions à deux photons 2S-6S ou 2S-6D et 1S-3S. Le chapitre 3 décrit le dispositif expérimental utilisé pour mesurer la transition 2S-6D, qui est excitée par un laser titane -saphir à 820nm. Le rayonnement à 205nm nécessaire à l'excitation de la transition 1S-3S est obtenu en doublant deux fois la fréquence du laser titane-saphir. Ces deux doublages successifs sont faits dans des cristaux non linéaires placés dans des cavités de surtension externes. Le chapitre 4 est entièrement consacré aux doublages de fréquence : après des rappels théoriques d'optique non linéaire, les deux cavités sont présentées en détail, ainsi que les résultats obtenus. Enfin, le chapitre 5 présente toute la recherche du signal sur la transition 1S-3S : la construction d'un jet d'atomes dans l'état fondamental et la mise au point du système de détection. Ce travail a permis d'obtenir une mesure préliminaire du déplacement de Lamb du niveau fondamental de l'atome d'hydrogène : L(1S) = 8172.850 (174) MHz dont le résultat est en très bon accord, aussi bien avec les mesures précédentes qu'avec les résultats théoriques les plus récents.

Escapin is an L-amino acid oxidase that produces antimicrobial metabolites collectively called “Escapin Intermediate Products” (EIP-K). EIP-K and H2O2 together were previously shown to be bactericidal towards diverse planktonic bacteria. The present work investigates the ability of EIP-K and H2O2 to antagonize bacterial biofilms, using Pseudomonas aeruginosa as a model. The project had three aims: 1) determine the most effective concentrations of EIP-K and H2O2 necessary to break down existing P. aeruginosa biofilms, using a crystal violet assay; 2) examine the ability of EIP-K + H2O2 to inhibit biofilm formation, using triphenyl tetrazolium chloride dye; and 3) determine the effect of EIP-K + H2O2 on the viability, biomass and structure of biofilms cultivated in flow cells using confocal laser scanning microscopy (CLSM). Results showed that EIP-K + H2O2 significantly reduced biofilm biomass relative to controls and that the compounds are effective at nanomolar concentrations.

Selected fungal strain for production of raw-starch-digesting enzyme by solid state fermentation was improved by sequential exposures to γ-irradiation of Co60, ultraviolet and treatments with Nmethyl-N'-nitrosoguanidine. Mutant Aspergillus sp. CXN2-3A was chosen and its production of raw-starch-digesting enzyme (RSDE) was improved 2 folds higher than that of wild type. Optimal condition for the production of the enzyme using wheat bran as the substrate was accomplished for the CXN2-3A. With the optimal fermentation condition and the solid medium supplemented with urea and NH4NO3, CoSO4, Tween 80, 1% glucose, CXN2-3A produced RSDE 19.23 folds higher than wild type cultured in pre-optimized condition and un-supplemented medium. / Chủng nấm chọn lọc sản xuất enzyme thủy phân tinh bột bằng cách lên men trạng thái rắn, chủng nấm được cải thiện bằng chiếu xạ tia cực tím, tia Co60 và các phương pháp xử lí với N-methyl-N'-nitrosoguanidine. Mutant Aspergillus sp. CXN2-3A, đã được lựa chọn để sản xuất enzyme (RSDE) thủy phân tinh bột sống cải thiện cao hơn 2 lần so với chủng dại. Điều kiện tối ưu cho việc sản xuất các enzyme bằng cách sử dụng cám, lúa mì đã được thực hiện cho CXN2-3A. Với điều kiện lên men xốp tối ưu và bổ sung urê và NH4NO3, CoSO4, Tween 80, 1% glucose, CXN2-3A đã sản xuất RSDE cao gấp 19,23 lần so với kiểu dại ở cùng điều kiện.

Orientador: Carlos Frederico Wilcken / Banca: Wilson Badiali Crocomo / Banca: Nádia Cristina de Oliveira / Banca: Edson Luiz Lopes Baldin / Banca: Ronaldo Pavarini / Resumo: A espécie Sarsina violascens (Herrich-Schaeffer, 1856) (Lepidoptera: Lymantriidae) é relatada como praga primária em plantios de eucalipto e teve sua primeira ocorrência registrada em 1975. No período de 2006 a 2009 houve grandes surtos dessa praga, causando desfolhamento intenso em plantios de eucalipto no norte da Bahia. Apesar dos estudos feitos no passado terem considerado espécies de eucalipto, há pouca informação sobre a suscetibilidade de clones híbridos de eucalipto à mariposa violácea. O presente trabalho teve por objetivo avaliar a biologia de S. violascens em diferentes espécies e híbridos de eucalipto e em diferentes temperaturas, além de avaliar a eficiência de entomopatógenos no controle de S. violascens. No experimento 1 a biologia de S. violascens foi determinada nas espécies Eucalyptus grandis, E. urophylla e dois híbridos de E. grandis x E. urophylla ('urograndis'). Os parâmetros avaliados foram duração e viabilidade dos estágios larval, pupal, adulto e de ovo e do ciclo total. No experimento 2 foi selecionada a espécie E. urophylla como padrão e avaliou-se o efeito de diferentes temperaturas (18, 22, 26 e 30oC) no desenvolvimento de S. violascens, avaliando-se os mesmos parâmetros anteriores. Os resultados obtidos no experimento 1 revelaram que E. urophylla ofereceu melhores condições para odesenvolvimento de S. violascens, com maior viabilidade larval (85,3 %), pupal (78,7 %) e de ovos (72,6 %), e menor duração do ciclo total (54,4 dias). A espécie E. grandis foi considerada a menos adequada ao desenvolvimento de S. violascens, revelando baixas viabilidades larval (29,2 %) e pupal (28,9 %). Os resultados obtidos com os dois híbridos foram intermediários comparativamente com as espécies testadas. No experimento 2 as temperaturas de 18, 22 e 26°C foram adequadas para o desenvolvimento e reprodução de S. violascens, com alta viabilidade... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Defoliator lepidopterous are one of the main Eucalyptus pest groups in Brazil. There are records of caterpillars outbreaks since 1940, with important occurrences during 1980's to 1990's. The species Sarsina violascens (Herrich-Schaeffer, 1856) (Lepidoptera: Lymantriidae), named as violet moth, is related as pest in eucalypts plantations since 1975 and during 2006 to 2009, this species has occurred in outbreaks, causing intense defoliation in eucalypt plantations in Northern Bahia, Brazil. Despite studies in the past have considered species of eucalyptus, there is little information about susceptibility of Eucalyptus hybrid clones to violet moth. This study aimed to determine the biology of S. violascens in different species and hybrids of eucalyptus and in different temperatures. The insects were observed diary to evaluate life cycle in different species of eucalyptus (experiment 1) and in different temperatures (experiment 2). In experiment 1 were tested the following species: Eucalyptus grandis, E. urophylla and two hybrids of E. grandis x E. urophylla ('urograndis'). The parameters evaluated were: duration and viability of larvae, pupae, adult and eggs phases and total life cycle. In experiment 2 was chose the species E. urophylla as standard and evaluated the effect of temperatures of 18, 22, 26 and 30oC, considering the same previous parameters. The results obtained in experiment 1 showed that E. urophylla offered better conditions to S. violascens development and reproduction, due the higher larvae, pupae and eggs viability, and shorter total life cycle duration. The species E. grandis was considered as less adequate to S. violascens development and reproduction, with low larvae and pupae viability. To the two hybrid clones, the results were intermediary comparatively with tested species. In experiment 2 temperature of 18°C showed the most adequate to S. violascens... (Complete abstract click electronic access below) / Doutor

Magister Scientiae - MSc (Chemistry) / The increasing cost of fossil fuel energy production and its implication in environmental pollution and climate change created high demand for alternative and renewable sources of energy. This has led to great interest in research in the field of photovoltaic or solar cells Due to the abundance of sunlight, the technology is sustainable, non-polluting and can be implemented at places where power demand is needed, for example in rural areas. Solar cell devices that have been commercialized are currently based on silicon technology, involving the use of monocrystalline, polycrystalline and amorphous silicon. Although they produce highly efficient solar cells, the cost of Si solar cells is too high. Second generation solar cell materials such as cadmium telluride and third generation materials such as perovskites and organic polymers have been receiving much attention recently. However, they lack the efficiency of Si solar cells. This research proposes the development of high energy conservation photovoltaic cells from novel low-cost organosilicon polymers. The aim was to develop novel highly branched organosilane polymers such as poly(3-hexythiophene), polydi(thien-2-yl)dimethylsilane, poly(3-hexyl- [2,2'] bithiophenyl-5-yl)-dimethyl-thiophen-2yl-silane) as electron donors along with zinc oxide nanorod as the electron acceptor which were able to bring the efficiency of the resultant photovoltaic cell close to that of current Si solar cell. / 2021-08-31

O material SiO2/Nb2O5 (SiNb) foi preparado pelo método sol-gel e empregado como adsorvente para remoção do corante Violeta Cristal. O material foi caracterizado utilizando isotermas de adsorção/dessorção de nitrogênio, espectroscopia FTIR, pHpzc, e SEM-EDS. A análise isotérmica de N2 revelou a presença de micro e mesoporos na amostra de SiNb com área superficial específica de 747 m2g−1. No processo de adsorção do corante foram avaliados parâmetros como pH, temperatura, tempo de contato, e concentração do corante no processo. O valor de pH inicial da solução do corante que levou a uma máxima adsorção foi 7. A cinética de adsorção e equilíbrio para a adsorção do corante foram representadas por ordem-geral e Liu, respectivamente. A capacidade máxima de adsorção do corante com o adsorvente SiNb, na temperatura de 303K, foi de 116mg g-1. Dois efluentes de corantes foram simulados e usados para verificar a aplicabilidade do material SiNb para tratamento de efluentes, sendo que o adsorvente se mostrou muito eficiente na descoloração desses efluentes. / In this dissertation, SiO2/Nb2O5 (SiNb) material was prepared using sol–gel method and employed as adsorbent for removal of crystal violet dye (CV). The material was characterized using nitrogen adsorption–desorption isotherms, FTIR spectroscopy, pHpzc, and SEM-EDS. The analysis of N2 isotherms revealed the presence of micro- and mesopores in the SiNb sample with specific surface area 747 m2 g−1. For the dye adsorption process, variations of parameters such as of pH, temperature, contact time, and concentration of dye of the process were evaluated. The optimum initial pH of the CV dye solution was 7.0. The adsorption kinetic and equilibrium data for CV adsorption were suitably represented by the general-order and Liu models, respectively. The maximum adsorption capacity of the CV dye by SiNb was achieved at 303 K, which attained 116 mg g−1at this temperaure. Dye effluents were simulated and used to check the applicability of the SiNb material for treatment of effluents – the material showed very good efficiency for decolorization of dye effluents.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / This work aimed to explore the association of molecular absorption spectrometry with multivariate calibration techniques to the simultaneous determination of Al(III) and Fe(III) in post-dialysis fluids, from the complexes built between the analytes and the chromogenic reagent Pyrocatechol Violet in hexamethylenetetramine buffered medium (pH 6.1). The Partial Least Squares Regression (PLS) method was used to the simultaneous determination of the analytes, in high salt samples, without the use of sample pre-treatment, masking agents or separation steps. The present technique consists in a simple, fast and low cost procedure. Binary mixtures of the analytes in high salt samples were used as calibration set, by using absorbance values of 580 wavelengths per sample. Concentrations values for Al(III) and Fe(III) in the ranging from 0.2 to 0.6 mg L-1 were obtained by the PLS method in post-dialysis fluids samples by using 3 PLS components. Predicted values obtained by PLS method were compared with voltammetric measurements by adsorptive stripping voltammetry for post-dialysis fluids samples spiked with the analytes. Both methods showed similar results to the determination of the analytes in post-dialysis fluids samples. / No presente trabalho, investigou-se a associação de métodos de espectrometria de absorção molecular (EAM) com métodos de calibração multivariada para a determinação simultânea de Al(III) e Fe(III) em fluidos pós-hemodiálise, a partir da formação dos complexos dos metais com o reagente Violeta de Pirocatecol em tampão hexametilenotetramina (pH 6,1). O método de regressão dos mínimos quadrados parciais (PLS) foi usado para a quantificação simultânea dos analitos, em amostras com alta concentração salina, sem a necessidade de pré-tratamento da amostra, uso de agentes mascarantes ou etapas de separação. A presente técnica consiste em um procedimento simples, rápido e de baixo custo. Empregaram-se misturas binárias dos analitos em solução pré-hemodiálise como grupo de calibração, utilizando-se dados de absorvância em 580 comprimentos de onda por amostra. Valores de concentração na faixa de 0,2 a 0,6 mg L-1 foram preditos para amostras de fluido pós-hemodiálise com o uso de 3 componentes principais. Dados de predição para amostras de fluido pós-hemodiálise adicionadas dos analitos foram comparados a medidas por voltametria adsortiva de redissolução (AdSV). Ambos os métodos apresentaram resultados similares para a determinação dos analitos em fluidos pós-hemodiálise.

abstract: The energy required in a eukaryotic cell is provided by mitochondria. Mitochondrial electron transport chain (ETC) coupled with oxidative phosphorylation generates ATP. During electron transport, electron leakage from the ETC produces reactive oxygen species (ROS). In healthy cells, there are preventive and defense mechanisms in place to manage ROS. Maintaining a steady balance of ROS is very important because overproduction of ROS can lead to several pathological conditions. There are several strategies to prevent ROS production. Addition of external antioxidants is widely used among them. Discussed in the first part of Chapter 1 is the mitochondrial ETC, ROS production and antioxidant strategies. The second part of Chapter 1 is concerned with ribosomal protein synthesis in bacteria. Ribosome, the organelle that synthesizes proteins with exceptional fidelity, has a strong bias for α-L-amino acids. It has been demonstrated that reengineering of the peptidyltransferase center (PTC) of the ribosome could enable the incorporation of both α-D-amino acids and β-amino acids into full length protein. Oxidative stress is a common cause of various neurological disorders such as Alzheimer’s disease and Parkinson’s disease. Antioxidative strategies are used widely for the treatment of these disorders. Although several antioxidants demonstrated positive results in vitro as well as in in vivo models, none of them have been effective in clinical settings. Hence, there is an ongoing search for effective neuroprotective drugs. Described in Chapter 2 is the synthesis and biological evaluation of several methylene blue analogues as potentially effective antioxidants for the treatment of pathologies related to oxidative stress. In Chapter 3, the synthesis and ribosomal incorporation of several rationally designed dipeptidomimetic analogues are discussed. The dipeptidomimetic analogues are structurally similar to the GFP chromophore and, therefore, highly fluorescent. In addition, the backbone of the dipeptidomimetic analogues resemble the peptide backbone of a dipeptide, due to which they can be incorporated into protein by modified ribosomes selected for the incorporation of dipeptides. Discussed in Chapter 4 is the synthesis of the pdCpA derivatives of several β-amino acids. The pdCpA derivatives were ligated to tRNA-COH and were used as probes for studying the regio- and stereoselectivity of modified ribosomes. / Dissertation/Thesis / Doctoral Dissertation Chemistry 2016

Made available in DSpace on 2014-06-11T19:27:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-04-17Bitstream added on 2014-06-13T20:35:52Z : No. of bitstreams: 1 almeida_acm_me_rcla.pdf: 908754 bytes, checksum: c67dc89a044d50c60fbdc87558d820a3 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O uso de biodigestores anaeróbios é uma versátil alternativa para produção de biomassa microbiana a partir de resíduos orgânicos. O reaproveitamento das sobras alimentares, produzidas pelo Restaurante Universitário da Unesp Campus Rio Claro, foi o responsável pela produção de um Inóculo Líquido Residual (I.L.R.) utilizado como agente biodegradador e biossorvente para os corantes azóicos “Acid Yellow 25” e “Direct Violet 51” de importante destaque industrial. O projeto dividiu-se em duas etapas, a primeira contemplando a produção do inóculo em grande escala (biodigestor de fluxo contínuo) e a segunda em escala de laboratorial (biodigestor em batelada). Os resultados da análise microbiológica revelaram a presença predominante de bactérias acidogênicas e de leveduras em menor escala. Estes microrganismos foram aplicados como inóculo nas soluções dos dois corantes em condições variadas de pH (2,50; 4,50 e 6,50). A análise dos produtos formados a partir da interação com o I.L.R demonstraram as potencialidades biodegradativas e biossorventes do consórcio microbiano e sua ação diferenciada de acordo com a mudança de pH.As aminas aromáticas e sulfonadas, formadas após a redução da ligação azóica, foram estudada a partir do sobrenadante dos tratamentos dos corantes através do uso dos métodos difundidos do UV-Vis e do HPLC aliados às analises vanguardistas do FTIR. / The use of anaerobic bioreactor is a versatile alternative for the production of microbial biomass from organic waste. The reuse of the leftovers from the University Restaurant of Unesp Rio Claro Campus, was responsible for producing a Residual Liquid Inoculum (R.L.I.) used as a biodegradator and biosorptive agent for two azo dyes Acid Yellow 25 and Direct Violet 51 with a major role in the industrial scenery. The project was divided in two steps, the first covering the production of the inoculum in large scale (continuous flow bioreactor) and the second in bench-scale (in-batch bioreactor) The results of the microbiological analysis revealed a predominant presence of acidogenic bacteria and a few yeasts. These microorganisms were used as inoculum in both dye solutions at different pH conditions (2.50, 4.50 and 6.50) The analysis of the resultant by-products demonstrated the biodegradation and biosorptive potential of the consortium and its differentiated pH-regulated action. The aromatic sulfonated amines, formed after the reduction of the azoic bounds, were studied through the spreaded analytic methods of UV-Vis and HPLC in conjunct with the vanguard of FTIR device.

Orientador: Carlos Renato Corso / Banca: Sandra Mara Martins Franchetti / Banca: Sandra Regina Ceccato Antonini / Resumo: O uso de biodigestores anaeróbios é uma versátil alternativa para produção de biomassa microbiana a partir de resíduos orgânicos. O reaproveitamento das sobras alimentares, produzidas pelo Restaurante Universitário da Unesp Campus Rio Claro, foi o responsável pela produção de um Inóculo Líquido Residual (I.L.R.) utilizado como agente biodegradador e biossorvente para os corantes azóicos "Acid Yellow 25" e "Direct Violet 51" de importante destaque industrial. O projeto dividiu-se em duas etapas, a primeira contemplando a produção do inóculo em grande escala (biodigestor de fluxo contínuo) e a segunda em escala de laboratorial (biodigestor em batelada). Os resultados da análise microbiológica revelaram a presença predominante de bactérias acidogênicas e de leveduras em menor escala. Estes microrganismos foram aplicados como inóculo nas soluções dos dois corantes em condições variadas de pH (2,50; 4,50 e 6,50). A análise dos produtos formados a partir da interação com o I.L.R demonstraram as potencialidades biodegradativas e biossorventes do consórcio microbiano e sua ação diferenciada de acordo com a mudança de pH.As aminas aromáticas e sulfonadas, formadas após a redução da ligação azóica, foram estudada a partir do sobrenadante dos tratamentos dos corantes através do uso dos métodos difundidos do UV-Vis e do HPLC aliados às analises vanguardistas do FTIR. / Abstract: The use of anaerobic bioreactor is a versatile alternative for the production of microbial biomass from organic waste. The reuse of the leftovers from the University Restaurant of Unesp Rio Claro Campus, was responsible for producing a Residual Liquid Inoculum (R.L.I.) used as a biodegradator and biosorptive agent for two azo dyes Acid Yellow 25 and Direct Violet 51 with a major role in the industrial scenery. The project was divided in two steps, the first covering the production of the inoculum in large scale (continuous flow bioreactor) and the second in bench-scale (in-batch bioreactor) The results of the microbiological analysis revealed a predominant presence of acidogenic bacteria and a few yeasts. These microorganisms were used as inoculum in both dye solutions at different pH conditions (2.50, 4.50 and 6.50) The analysis of the resultant by-products demonstrated the biodegradation and biosorptive potential of the consortium and its differentiated pH-regulated action. The aromatic sulfonated amines, formed after the reduction of the azoic bounds, were studied through the spreaded analytic methods of UV-Vis and HPLC in conjunct with the vanguard of FTIR device. / Mestre