Made available in DSpace on 2014-12-17T15:36:58Z (GMT). No. of bitstreams: 1 Luciane Dutra Coletti_DISSERT.pdf: 1662787 bytes, checksum: ee4eb6d750011a6b9a0e7fbe38856b71 (MD5) Previous issue date: 2010-05-20 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Seeing colors can be advantageous, because they are an important signal for providing information about the environment, such as the location of food. However, not every animals sees these chromatic signals in the same way. In primates, the group of Plathyrrhini has polymorphic sex-linked vision with males always dichromats and dichromats or trichromats females. Studies indicate that trichromats during foraging would benefit by seeing better than dichromats ripe fruits against the green foliage background. On the other hand, dichromats appear to distinguish camouflaged insects better than trichromats. The marmoset (Callihtrix jacchus) is a neotropical primate species that have color vision polymorphism. This species establishes family groups with highly reproductive bias, with breeding females often having preferential access to food. This work aims to study whether the social context influences the foraging ability of camouflaged and red items in groups of C. jacchus. Four groups of captive marmosets were presented to four food tasks, involving difficult, easy, reddish and camouflaged food targets. Foods were presented in a concentrated and dispersed manner, to check whether there was monopolization of the resources by the dominant subjects and if this would affect the ability of individuals to find the food targets. Success was measured by latency to food acquisition and number of targets consumed. Males and females differed in their foraging success for camouflaged and reddish items, although this difference has not appeared in all situations and experimental conditions. In general males were more successful for detecting camouflaged items while females succeeded more in identifying reddish items. There were no differences in foraging success between individuals of different social status, however, there were differences in the success of consumption of food items for different situations when food was concentrate compared with dispersed food. Taken as a role, there was a greater difficulty in detecting food items when they were presented in concentrated arrangement, which is supposed to be related to a higher difficulty to approach and stay near the food. Although it appears that there was no direct competition seems to have group's indirect influence on the detection of food items and foraging success of individuals, affecting mainly those items more difficult to detect / Enxergar cores pode ser vantajoso, j? que elas s?o um importante sinal por fornecer informa??es a respeito do ambiente, tal como a localiza??o do alimento. No entanto, nem todos os animais enxergam estes sinais crom?ticos da mesma forma. Nos primatas, o grupo dos Plathyrrhini possui vis?o polim?rfica ligada ao sexo, com os machos sempre dicromatas e as f?meas podendo ser dicromatas ou tricromatas. Estudos indicam que os tricromatas teriam vantagens no forrageio por enxergar melhor que os dicromatas os frutos maduros avermelhados contra o fundo verde de folhagens. J? os dicromatas distinguiriam melhor insetos camuflados do que os tricromatas. O sag?i (Callithrix jacchus) ? uma esp?cie de primata neotropical que possui vis?o de cores polim?rfica. Esta esp?cie constitui grupos familiares com alto vi?s reprodutivo e as f?meas reprodutoras geralmente t?m acesso preferencial ao alimento. Neste trabalho verificou-se se este contexto social exerce influ?ncia na habilidade de forrageio de itens camuflados e avermelhados em grupos de C. jacchus. Foram apresentadas a quatro grupos de sag?is cativos quatro tarefas alimentares, com alvos alimentares dif?ceis, f?ceis, avermelhados e camuflados. Os alimentos foram apresentados de forma concentrada e de forma dispersa, para verificar se haver? monopoliza??o do recurso pelos sujeitos dominantes e se esta afetaria a habilidade dos indiv?duos em encontrar os alvos alimentares. O sucesso foi medido atrav?s do tempo de lat?ncia na aquisi??o e n?mero de itens consumidos. Machos e f?meas diferiram no sucesso de forrageio para itens camuflados e avermelhados, embora esta diferen?a n?o tenha aparecido em todas as situa??es e condi??es experimentais. De forma geral machos tiveram mais sucesso para os itens camuflados e as f?meas mais sucesso para os itens avermelhados. N?o foram encontradas diferen?as no sucesso de forrageio entre indiv?duos de status sociais diferentes, no entanto, existiram diferen?as no sucesso de aquisi??o de itens alimentares em diferentes situa??es experimentais quando o alimento era apresentado concentrado em rela??o a quando era apresentado disperso. No todo, houve uma maior dificuldade de detec??o dos itens alimentares quando estes eram apresentados concentrados, sugerindo uma maior dificuldade de aproxima??o e perman?ncia nas proximidades do alimento. Embora pare?a n?o ter existido uma competi??o direta, ? poss?vel ter havido influ?ncia indireta do grupo na detec??o dos itens alimentares e no sucesso de forrageio dos indiv?duos, influindo principalmente naqueles itens de mais dif?cil detec??o pelos animais

Made available in DSpace on 2014-06-12T16:29:46Z (GMT). No. of bitstreams: 2 arquivo2743_1.pdf: 2012890 bytes, checksum: 990d95aa03c535d23d043c7880f92539 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2011 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A espectrofotometria no ultravioleta-visível (UV/Vis) e a cromatografia líquida de alta eficiência (CLAE) destacam-se dentre os métodos analíticos empregados para quantificação de flavonóides em drogas vegetais. Entretanto, questionamentos sobre a especificidade e equiparação de seus resultados vem sendo suscitados diante das características e limitações de cada técnica. Dessa forma, o objetivo principal deste trabalho foi avaliar comparativamente a CLAE e metodologias espectrofotométricas para quantificação de flavonóides em folhas de Bauhinia forficata Link (pata de vaca), com o intuito de estabelecer especificações analíticas que permitam que as técnicas possam ser empregadas alternativamente. Buscou-se também estabelecer especificações para o controle de qualidade da espécie escolhida, por meio de amostras do material vegetal, obtidas de duas regiões do Brasil, que foram submetidas à caracterização fitoquímica e físicoquímica (granulometria, perda por dessecação, teor de cinzas e teor de extrativos). Para a avaliação dos métodos analíticos, foram desenvolvidas e validadas, segundo o ICH e RE nº 899/03 (ANVISA), técnicas espectrofotométricas para quantificação de flavonóides totais, uma por diluição direta e outra por hidrólise ácida, e uma metodologia por CLAE para quantificação do marcador canferitrina. As respostas encontradas para três níveis de concentração foram avaliadas estatisticamente. Observou-se para as duas amostras um perfil fitoquímico similar, apresentando: flavonóides, proantocianidinas, leucoantocianidinas, triterpenos e esteróides. Constatou-se que o tamanho de partícula e a umidade residual mostraram-se divergentes em virtude da origem e do processamento adotados pelos fornecedores. Sendo que os valores do teor de cinzas mostraram-se dentro das especificações e não foi observada diferença significativa para o teor de extrativos. As metodologias desenvolvidas mostraram-se específicas, sensíveis, precisas, exatas e robustas, sendo adequadas para as análises realizadas. As amostras de B. forficata mostraram resultados similares para os dois procedimentos espectrofotométricos, porém apenas uma delas apresentou canferitrina. Por isso, questiona-se a adoção desse constituinte como marcador apropriado para a espécie, haja vista que pode comprometer o emprego de CLAE como ferramenta analítica. Por outro lado, considerando que a canferitrina apresenta as propriedades físico-químicas de seu grupo de metabólitos, sua ausência em uma das amostras não invalida a avaliação do desempenho dos métodos, pois a observação de desempenho similar para o método seletivo (CLAE) e o método para quantificação de grupos, pode conferir maior confiabilidade a técnica geral e sugere comportamento similar para compostos estruturalmente semelhantes. Portanto, o estudo comparativo foi conduzido apenas com a amostra contendo canferitrina e permitiu estabelecer correlação positiva e ausência de erros sistemáticos significativos entre todos os procedimentos, indicando que os mesmos podem ser utilizados alternativamente sem que haja prejuízo de suas respostas. Dessa forma, considerando ainda a simplicidade, baixo custo de execução e variabilidade intrínseca da matriz em questão, a adoção das técnicas espectrofotométricas permanecem como alternativas válidas para análise de flavonóides em folhas de B. Forficata. Por fim, os resultados obtidos neste trabalho contribuíram no processo de identificação e padronização de parâmetros de qualidade para a planta supracitada

Made available in DSpace on 2014-06-12T23:13:19Z (GMT). No. of bitstreams: 2 arquivo2643_1.pdf: 948572 bytes, checksum: fdfaa21b513d1dab3602059ce3b208f5 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2009 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Filmes coloridos à base de poli(metacrilato de metila) (PMMA) foram preparados com a finalidade de obtenção de dosímetros plásticos para atender as necessidades do mercado nacional. Neste projeto, os corantes azul de bromotimol (AB) e vermelho fenol (VF), em diferentes concentrações, foram utilizados na formulação dos sistemas poliméricos dosimétricos PMMA/AB e PMMA/VF, respectivamente. Estes sistemas têm características dosimétricas com aplicações industriais em áreas de radioesterilização de artefatos médicos e alimentos. A resposta dosimétrica (absorbância) dos sistemas mostrou boa correlação linear (R2 > 0,95) no intervalo de doses de 5 100 kGy (sistema PMMA/AB, λ = 403nm) e 2 25 kGy (sistema PMMA/VF, λ = 406nm). Foram investigadas também a dependência da resposta com a taxa de dose dos sistemas nas taxas de 8,148 kGy/h e 4,074 kGy/h, assim como a estabilidade da resposta com o tempo de armazenamento em diferentes condições de temperatura e exposição à luz fluorescente. Os resultados mostram que ambos os sistemas, PMMA/AB e PMMA/VF, apresentam boa estabilidade quando os filmes são armazenados à temperatura de ~10°C, protegidos da luz fluorescente antes e após a irradiação durante 60 dias (sistema PMMA/AB) e 80 dias (sistema PMMA/VF). Entretanto, estes sistemas apresentam dependência com a taxa de dose, sendo necessária a utilização de curvas de calibração únicas para cada taxa de dose

L’objectif de ces travaux est de développer une nouvelle voie de valorisation de différents coproduits agricoles et forestiers. L’étude s’est focalisée sur l’étape de séparation entre les hémicelluloses et les lignines contenues dans des extraits aqueux obtenus par extrusion bi-vis. La technologie bi-vis du fait de sa modularité a été choisie pour évaluer différentes conditions d’extraction. Les essais ont été menés afin de mettre en évidence l’influence des effets mécanique, thermique et chimique sur l’extraction des hémicelluloses à partir des différentes matrices végétales étudiées. Les travaux ont été conduits soit en conditions hydrothermales, eau sous pression et haute température, soit en conditions faiblement alcalines pour extraire des molécules les plus natives possibles. Ceci a permis d’identifier les conditions d’extraction les plus favorables en fonction des caractéristiques de chacune des biomasses. Dans un second temps, les extraits obtenus, contenants des hémicelluloses et des composés phénoliques, ont été purifiés au moyen de méthode de fixation sur résines d’échange d’ions et d’adsorption. Les travaux se sont focalisés sur la compréhension des mécanismes de fixation des molécules avec des solutions modèles contenant un ou plusieurs solutés. La cinétique et les isothermes d’échanges ont été évaluées pour l’acide férulique, l’acide coumarique et la lignine. Les résultats ont ensuite été comparés à ceux obtenus avec les extraits alcalins. Cette étude a permis d’identifier les mécanismes d’échanges qui interviennent lors de la séparation des complexes lignine-polysaccharides.

Pesticide testing is of practical interest in various areas of today’s world due to their prevalence and toxicity. These areas include agriculture, environmental, chemical plants, and many others. Herbicides, like Roundup, contain secondary amines such as glyphosate. The ability to detect secondary amines could offer a method for glyphosate detection in agricultural and environmental samples. Secondary amines can interact with metal complexes through electron charge transfer. Such interactions can cause a change in the metal’s electron configuration and energy state and can be seen in the UV-Vis spectrum. Metal phthalocyanines (MPc’s) and other organometallic complexes have been of interest for these reasons and may be applicable to glyphosate detection without extensive laboratory tests. UV-Vis absorption can further provide quantitative measurements. An evaluation of FeTSPc’s ability to aid in remediation via adsorption supports was also examined.

Synthetische anorganische Knochenersatzmaterialien auf Calcium-Phosphat- und Magnesium-Phosphat-Basis wurden in der hier vorliegenden Dissertation mit verschiedenen handelsüblichen Antibiotika versetzt und deren Freisetzungsverhalten charakterisiert. Zudem wurde der Einfluss des Antibiotikazusatzes auf bestimmte materialcharakteristische Eigenschaften untersucht, hierbei fanden die Quecksilberporosimetrie, die Röntgendiffraktometrie und die Rasterelektronenmikroskopie ihre Anwendung. Insbesondere für die Knochenersatzmaterialien auf Calcium-Phosphat-Basis sollte eine klinisch praktikable und demnach möglichst einfache Methode etabliert werden, um die Kombination mit einem Antibiotikum durchzuführen. Die Detektion der Antibiotika erfolgte mit Hilfe eines UV/VIS-Spektrophotometers. Zudem wurde für einige ausgewählte Kombinationen aus Antibiotikum und Knochenersatzmaterial durch einen Agardiffusionstest die antibakterielle Wirkung nach der Freisetzung aus dem jeweiligen Trägermaterial bestätigt. / Synthetic inorganic bone substitute materials based on calcium phosphate and magnesium phosphate were mixed with various commercially available antibiotics and their release behavior was characterized in the present dissertation. In addition, the influence of the antibiotic addition on certain material characteristic properties was investigated using mercury porosimetry, X-ray diffractometry and scanning electron microscopy. For the calcium-phosphate-based bone substitutes in particular, the aim was to establish a clinically practicable and therefore as simple as possible method for carrying out the combination with an antibiotic. Antibiotics were detected using a UV/VIS spectrophotometer. In addition, for some selected combinations of antibiotic and bone substitute material, an agar diffusion test was used to confirm the antibacterial effect after release from the respective carrier material.

This publication is dedicated to investigate strong light-matter coupling with excitons in 2D materials. This work starts with an introduction to the fundamentals of excitons in 2D materials, microcavities and strong coupling in chapter 2. The experimental methods used in this work are explained in detail in chapter 3. Chapter 4 covers basic investigations that help to select appropriate materials and cavities for the following experiments. In chapter 5, results on the formation of exciton-polaritons in various materials and cavity designs are presented. Chapter 6 covers studies on the spin-valley properties of exciton-polaritons including effects such as valley polarization, valley coherence and valley-dependent polariton propagation. Finally, the formation of hybrid-polaritons and their condensation are presented in chapter 7. / Diese Veröffentlichung beschäftigt sich mit starker Licht-Materie Kopplung mit Exzitonen in 2D Materialien. Dies Arbeit beginnt mit einer Einführung in Exzitonen in 2D Materialien, in Mikrokavitäten und starke Licht-Materie Kopplung (Kapitel 1). Die verwendeten, experimentellen Methoden werden in Kapitel 3 beschrieben. Kapitel 4 deckt Voruntersuchungen ab, die helfen die richtigen Materialien und Mikrokavitäten für die folgenden Experimente auszuwählen. In Kapitel 5 werden die Ergebnisse zur Erzeugung von Exziton-Polaritonen in verschiednen Materialen und Kavitäten gezeigt. Kapitel 6 beschäftigt sich mit Untersuchungen der Spin-Tal Eigenschaften der Exziton-Polaritonen, inkl. Effekte wie Tal Polarisation und Koherenz. Abschließend wird in Kapitel 7 die Erzeugung von Hybrid-Polaritonen und deren Kondensation dargestellt.

The continuously increasing demand for innovation in the miniaturization of microelectronics has driven the need for ever more precise fabrication strategies for device packaging, especially for printed circuit boards (PCBs). Subtractive copper etching is a fundamental step in the fabrication process, requiring very precise control of etch rate and etch factor. Changes in the etching chemical equilibrium have significant effects on etching behavior, and CuCl2 / HCl etching baths are typically monitored with several parameters including oxidation-reduction potential, conductivity, and specific gravity. However, the etch rate and etch factor can be difficult to control even under strict engineering controls of those monitoring parameters. The mechanism of acidic cupric chloride etching, regeneration and recovery is complex, and the current monitoring strategies can have difficulty controlling the interlocking chemical equilibria. A complimentary tool, thin-film UV-Vis spectroscopy, can be utilized to improve the current monitoring strategies, as UV-Vis is capable of identifying and predicting etching behavior that the current standard methodologies have difficulty predicting. Furthermore, as a chemically-sensitive probe, UV-Vis can investigate the complex changes to the chemical equilibrium and speciation of the etch bath, and can contribute overall to significant improvements in the control of the copper etching system in order to meet the demands of next-level design strategies.

Magnetite, an iron oxide, is a possible candidate for in situ remediation of contaminated groundwater systems due to its oxidation/reduction potential for reduction of contaminants such as carbon tetrachloride. Little characterization and analysis has been done to describe the kinetics of magnetite transformation during oxidation. This work focuses on monitoring the concentrations of magnetite and one of its oxidation transformation products, maghemite, by the use of UV-Vis-NIR spectroscopy. As oxidation proceeded at a constant specific temperature, the concentration of magnetite decreases, which was indicated by a decrease in absorption in the NIR-region of the spectrum. As magnetite concentrations decreased, the concentration of maghemite increased, which was indicated by an increase in absorption in the UV-region. The temperature at which the suspensions of magnetite and maghemite were measured was of great importance for complete understanding of the magnetite transformation as seen by UV-Vis-NIR spectroscopy analysis. Higher measurement temperatures produced higher absorptivities of FeII-FeIII electron hopping transitions, while decreasing the absorptivity of FeIII-FeIII in the NIR and UV-regions respectively. Lower temperatures produced the opposite effects on the iron oxides' transitions. Higher temperature increased the rate of oxidation. / Master of Science

2-Nitrobenzanthron (2-NBA) and 3-nitrobenzanthron (3-NBA) are pollutants widely occurring in the environment. The main sources of benzanthrones are combustion products (i.e. diesel exhausts, wood and cigarette smoke ...). 3-NBA is proven strong mutagen and carcinogen for bacteria and mammals and it is probably mutagenic also to humans, while 2- NBA shows genotoxic properties lower by 3-4 orders of magnitude. Here we consider the possibility that large difference in the solubility, and consequently also the difference in bioavailability of these isomers could be the factor partially explaining this phenomenon. One goal was to determine solubility of 2-NBA in water and compare it with 3-NBA and also with other carcinogens studied in our laboratory (Sudan I, ellipticin). Another objective was to evaluate the effect of model proteins (bovine serum albumin, lysozyme) on solubility of Sudan I and ellipticine. The last aim was to determine extinction coefficients of these compounds in water and in methanol. Two different methods were employed to determine the solubility of the model compounds. The first method was based on spectrophotometric verification of the Lambert- Beer law. The results were than compared with other method measuring concentration of a compound in saturated solution (In Czech) Key...