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Mapping and analyzing the Florida Reef Tract in Palm Beach County in relation to major storm events in a GIS databaseUnknown Date (has links)
The Florida Reef Tract in Southeast Florida is made up of hard-bottom formations. The shape and size of the tract is constantly changing. One major factor contributing to these changes is the movement of sand. This is influenced by location-based, human-induced, and natural factors. These shifting sands cover or uncover reef structure. Images of the Florida Reef Tract in Palm Beach County were analyzed by the Department of Geosciences at Florida Atlantic University, using a partially automated method of mapping. There are notable changes in reef structure throughout the years 2004-2006, in which many major storm events occurred in the region. A time series analysis was conducted throughout these years. Losses and gains of reef structure were quantified and compared throughout the county as a whole, in beach renourishment project areas, and inlet intervals. Trends suggest that the major storms of 2004-2006 may have had effects on the reef tract. / by Joseph G. Pitti. / Thesis (M.A.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2011. Mode of access: World Wide Web.
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Obtenção de lipídios estruturados por interesterificação de triacilgliceróis de cadeia média e longa. / Synthesis of structured lipids obtain from interesterification reaction of medium and long chain tryacylglicerols.Denise D'Agostini 19 November 2001 (has links)
Através da mistura de óleos e gorduras e de posterior interesterificação, é possível obter compostos denominados de lipídios estruturados. Estes compostos formados pelo rearranjo de triacilgliceróis de cadeias médias e longas apresentam características físicas, químicas e nutricionais diferentes dos lipídios que lhes deram origem. Devido a sua potencial capacidade para a prevenção e tratamento de doenças, também podem ser considerados "nutracêuticos" por apresentarem vantagens clínicas que se encontram associadas aos ácidos graxos de cadeia média (AGCM) e à estrutura particular de sua molécula lipídica formada pela interesterificação. Esta pesquisa empregou dois métodos de modificação de óleos e gorduras: mistura e interesterificação. As matérias-primas utilizadas foram gorduras refinadas de palma e de palmiste, e triacilgliceróis de cadeia média (Trigliceril CM). Foi utilizado um planejamento de dez experimentos. Para as respostas analíticas foi aplicado um modelo de regressão múltipla, do tipo cúbico especial. Os resultados foram apresentados em diagramas triangulares. Estabeleceu-se ainda a correlação entre medidas quantitativas de aspectos morfológicos microscópicos com as características físicas das gorduras. Foram realizadas análises dos pontos de amolecimento e fusão, viscosidade, consistência, conteúdo de gordura sólida, distribuição estereoespecífica dos ácidos graxos através de hidrólise enzimática, e estrutura cristalina das amostras antes e após a reação de interesterificação química. A análise dos resultados indicou que as interações ocorridas entre os três componentes não foram significativas para os pontos de amolecimento e fusão, para a viscosidade e para a consistência antes da interesterificação, e, para o conteúdo de gordura sólida antes e após a interesterificação. Os coeficientes negativos para os parâmetros analisados demonstraram a existência de um efeito antagônico, próprio de interações eutéticas entre misturas de gorduras. Os pontos de amolecimento e de fusão foram dependentes das gorduras de palma e palmiste e das interações ocorridas entre os triacilgliceróis de cadeia média (TCM) e as gorduras de palma e palmiste. A viscosidade dependeu das gorduras de palma, palmiste e TCM. A consistência dependeu das gorduras de palma e palmiste e das interações binárias entre TCM e palmiste e entre palma e palmiste. O conteúdo de gordura sólida dependeu das gorduras de palma e palmiste e das interações binárias entre elas. Estabeleceram-se, ainda, diagramas triangulares, onde foram indicadas curvas de níveis. Os resultados da distribuição estereoespecífica demonstraram que, antes do rearranjo ao acaso, houve preferência do ácido oléico pela posição sn-2, enquanto que os ácidos palmítico e esteárico distribuíram-se principalmente pelas posições sn-1 e sn-3. Nos lipídios estruturados, os ácidos graxos saturados aumentaram sua participação na posição central do triacilglicerol, enquanto os ácidos graxos insaturados apresentaram diminuição nesta mesma posição. Para a estrutura cristalina foram determinados a dimensão fractal, o diâmetro e o número dos cristais, às temperaturas de 15, 20, 25 e 30ºC. Os números de cristais estiveram compreendidos entre 38 a 5245 e entre 33 a 3318, antes e depois da interesterificação, respectivamente. A dimensão fractal variou de 1,47 a 2,44 e de 1,35 a 2,59, antes e após a interesterificação, respectivamente. Os diâmetros médios dos cristais antes da interesterificação estiveram na faixa de 11,93 a 643,48m e, após a interesterificação, os valores variaram de 12,96 a 299,20m. Os lipídios estruturados apresentaram menor número de cristais e menores dimensões fractais que as misturas originais, com exceção da amostra que continha 2/3 de gordura de palma. / Structured lipids are compounds that can be synthesized by blending followed interesterification of fats and oils. These compounds, formed by rearrangement of medium and long chain tryacylglicerols show physical, chemical and nutritional characteristics different from the original lipids. They can also be considered nutraceuticals because of their potentiality in preventing and treating illnesses. This is due to the present clinical advantages associated to the medium chain fatty acids (MCFA) and also, the particular structure of the lipidic molecule formed by the interesterification. Two lipid modification methods were used in this study: blending and interesterification. Refined palm oil, palm kernel oil and medium chain tryacylglicerols (Trigliceril CM) were used as raw material. Ten experiments were planned and carried out. A mathematical model using the special cubic type multiple regression was applied to the analytical responses obtained. The results were shown in triangular diagrams where the contour curves were traced. A correlation between the quantitative measures of the microscopic morphologic aspects and the physical characteristics of the lipids was also established. The following analysis were carried out: determination of softening and melting points, viscosity, consistency, solid fat content, stereospecific distribution of fatty acids by enzymatic hydrolysis technique, and crystal structure of samples obtained before and after chemical interesterification. The results show that the interactions that occurred amongst the three components were not significant in relation to the softening and melting points, the viscosity, and the consistency before interesterification, and the solid fat content before and after interesterification. The negative coefficients of the parameters analyzed show an antagonic effect, which is characteristic of eutectic interactions amongst fats. The softening and melting points depended on the palm and palm kernel fats, and on the interactions that occurred between the medium chain tryacylglicerols (MCT) and the palm and palm kernel fats. The viscosity depended on the palm and palm kernel fats and on the medium chain tryacylglicerols (MCT). The solid fat content depended on the palm and palm kernel fats and on the binary interactions between them. The results of the stereospecific distribution showed that, instead of a random distribution, oleic acid was preferably esterified at the sn-2 position, whereas palmitic and stearic acids were mainly distributed at the sn-1 and sn-3 positions. The saturated fatty acids in the structured lipids increased their participation in the tryacylglicerol central position, whereas the unsaturated fatty acids decreased their participation at the same position. Fractal dimension, crystal diameter, and crystal number at 15, 20, 25 and 30ºC were determined to analyze the crystal structure. Fractal dimension varied from 1,47 to 2,44 and from 1,35 to 2,59 before and after the interesterification reaction, respectively. The crystal number varied from 38 to 5245 and from 33 to 3318, before and after the interesterification reaction, respectively. The average diameter of the crystals before interesterification varied from 11,93 to 643,48m and, after interesterification, these values varied from 12,96 to 299,20m. Structured lipids showed a smaller crystal number and smaller fractal dimensions than the original mixtures, with exception of the sample containing 2/3 of palm oil.
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Funcionalidade de gorduras na formulação de creme de amendoim / Functionality of fats in the formulation of peanut cream.Sylvio Jorge Hares Junior 18 October 2013 (has links)
O creme de amendoim é um produto popular no Brasil pelo seu excelente sabor e características nutricionais. No entanto, apesar de seu consumo consagrado e de seguir padrões rigidamente estabelecidos de processos e qualidade, pode ocorrer alteração na consistência e diminuição de características de espalhamento, diminuindo a qualidade sensorial. Como forma de procurar controlar estes problemas, são normalmente usados ingredientes gordurosos como promotores de melhoria de estabilidade e consistência, como óleo de palma, estearina de palma, oleína de palma, óleos hidrogenados, monoacilgliceróis e diacilgliceróis. O projeto teve como objetivo a formulação de cremes de amendoim com óleo de amendoim, óleo de palma e estearina de palma em várias proporções, visando a obtenção de produtos mais estáveis e consistentes, que sejam equivalentes aos produtos comerciais de largo consumo por consumidores no mercado nacional. Foram realizadas as seguintes análises nas gorduras e suas misturas: composição em ácidos graxos e triacilgliceróis, índices de iodo e de peróxido, acidez, consistência, conteúdo de gordura sólida e análise térmica de cristalização e fusão. Os ácidos graxos saturados foram predominantes na estearina e óleo de palma, principalmente o ácido palmítico, enquanto o óleo de amendoim tem como principal constituinte o ácido oleico. À medida que aumenta a proporção de óleo de amendoim nas misturas, aumentam a quantidade de ácidos graxos insaturados e o índice de iodo e diminui a quantidade de ácidos graxos saturados. Os pontos de fusão , entalpia total de fusão, consistência e conteúdo de gordura sólida aumentaram nas misturas que apresentavam maior proporção de estearina e óleo de palma, em função do aumento no teor de triacilgliceróis trissaturados. Para a consistência (mistura de gorduras e cremes formulados), o conteúdo de gordura sólida, a entalpia total de cristalização e fusão e o ponto de fusão das misturas de gorduras foi aplicado um modelo de regressão múltipla, procurando evidenciar a influência das gorduras nas propriedades do produto final. As interações entre as gorduras foram do tipo eutético, caracterizando incompatibilidade no estado sólido. O modelo de regressão múltipla foi considerado preditivo para a consistência dos cremes, o conteúdo de gordura sólida e para as os resultados da análise térmica. Os resultados mostraram que as misturas de maior potencial para a consistência ideal de cremes espalháveis (200-800 gf/cm2) na faixa da temperatura de uso, ou seja, desde temperatura de conservação em geladeira até temperatura de mesa (15 - 25°C), foram as seguintes: 50% de óleo de palma e 50% de estearina de palma; 66,6% de óleo de palma, 16,7% de óleo de amendoim e 16,7% de estearina de palma; 16,7% de óleo de palma, 16,7% de óleo de amendoim e 66,6% de estearina de palma. Portanto, estas amostras apresentavam larga faixa de presença de óleo de palma e/ou estearina de palma na formulação. Os resultados obtidos mostram que a simples mistura é uma forma eficaz para modificar as propriedades físicas e químicas de estearina de palma, óleo de amendoim e óleo de palma. As misturas permitiram a obtenção de gorduras com vários graus de consistência ,de conteúdo de gordura sólida e ponto de fusão, possibilitando a obtenção de cremes de amendoim formulados a partir delas, que eram mais estáveis e firmes, porém plásticos e consistentes o suficiente para garantir efetiva espalhabilidade e correspondência ao padrão observado nas melhores marcas de cremes de amendoim do mercado. / The peanut cream is a popular product in Brazil for its excellent flavor and nutritional characteristics. However, despite its huge consumption and to follow strict patterns of quality and processes, some alterations may occur in consistency that can reduce spread characteristics, lowering the sensorial quality. As a way to try to control these problems, fatty ingredients are typically used as promoters to improve stability and consistency, as palm oil, palm stearin, palm olein, hydrogenated oils, monoacylglycerols and diacylglycerols. The project aimed to formulate creams with peanut oil, palm oil and palm stearin in various proportions in order to obtain a more stable and consistent product, equivalent to the best commercial creams widely consumed in the brazilian market. The following analyzes were performed on fats and their blends: fatty acids and triacylglycerols composition, iodine and peroxide values, acidity, consistency, solid fat content and thermal analysis of melting and crystallization. Saturated fatty acids have been prevalent in palm stearin and palm oil, particularly palmitic acid, while peanut oil has at its main constituent the oleic acid. As peanut oil increases in the blends, increases the amount of unsaturated fatty acids and the iodine value and reduces the amount of saturated fatty acids. Fat blends with a high proportion of saturated fatty acids (palm stearin and palm oil), showed higher melting points, total enthalpy of melting, consistency and solid fat content, due to the increase of the content of trisatured triacylglycerols. For the consistency (fats blends and formulated creams), solid fat content, total enthalpy of melting and crystallization and melting point of the fat blends, a multiple regression model was applied in order to show how fats influence the properties of the final product. Interactions between fats were eutectic, showing incompatibility in the solid state. The multiple regression model was considered predictive for the consistency of the cream, solid fat content and results of the thermal analysis. The results showed that the mixtures of higher potential for optimal consistency of spreadable cream (200 to 800 gf/cm2) in temperature range from the storage at a refrigerator temperature up to the ambient temperature (10 - 25 °C) were: 50% palm oil and 50% palm stearin, 66.6% palm oil, 16.7% peanut oil and 16.7% palm stearin; 16.7 % palm oil, 16.7% peanut oil and 66.6% palm stearin. Therefore, these samples had a broad range presence of palm oil and / or palm stearin in the formulation. The results obtained showed that a simple mixture is an effective way to modify physical and chemical properties of palm stearin, peanut oil and palm oil. The mixtures enabled to obtain fats with various degrees of consistency, solid fat content and melting point parameters, making it possible to obtain peanut creams made from them which were more stable and firm but plastic and consistent enough to ensure effective spreadability and correspondence to the pattern observed in the best brands of peanut creams of the brazillian market.
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Obtenção de lipídios estruturados por interesterificação de triacilgliceróis de cadeia média e longa. / Synthesis of structured lipids obtain from interesterification reaction of medium and long chain tryacylglicerols.D'Agostini, Denise 19 November 2001 (has links)
Através da mistura de óleos e gorduras e de posterior interesterificação, é possível obter compostos denominados de lipídios estruturados. Estes compostos formados pelo rearranjo de triacilgliceróis de cadeias médias e longas apresentam características físicas, químicas e nutricionais diferentes dos lipídios que lhes deram origem. Devido a sua potencial capacidade para a prevenção e tratamento de doenças, também podem ser considerados "nutracêuticos" por apresentarem vantagens clínicas que se encontram associadas aos ácidos graxos de cadeia média (AGCM) e à estrutura particular de sua molécula lipídica formada pela interesterificação. Esta pesquisa empregou dois métodos de modificação de óleos e gorduras: mistura e interesterificação. As matérias-primas utilizadas foram gorduras refinadas de palma e de palmiste, e triacilgliceróis de cadeia média (Trigliceril CM). Foi utilizado um planejamento de dez experimentos. Para as respostas analíticas foi aplicado um modelo de regressão múltipla, do tipo cúbico especial. Os resultados foram apresentados em diagramas triangulares. Estabeleceu-se ainda a correlação entre medidas quantitativas de aspectos morfológicos microscópicos com as características físicas das gorduras. Foram realizadas análises dos pontos de amolecimento e fusão, viscosidade, consistência, conteúdo de gordura sólida, distribuição estereoespecífica dos ácidos graxos através de hidrólise enzimática, e estrutura cristalina das amostras antes e após a reação de interesterificação química. A análise dos resultados indicou que as interações ocorridas entre os três componentes não foram significativas para os pontos de amolecimento e fusão, para a viscosidade e para a consistência antes da interesterificação, e, para o conteúdo de gordura sólida antes e após a interesterificação. Os coeficientes negativos para os parâmetros analisados demonstraram a existência de um efeito antagônico, próprio de interações eutéticas entre misturas de gorduras. Os pontos de amolecimento e de fusão foram dependentes das gorduras de palma e palmiste e das interações ocorridas entre os triacilgliceróis de cadeia média (TCM) e as gorduras de palma e palmiste. A viscosidade dependeu das gorduras de palma, palmiste e TCM. A consistência dependeu das gorduras de palma e palmiste e das interações binárias entre TCM e palmiste e entre palma e palmiste. O conteúdo de gordura sólida dependeu das gorduras de palma e palmiste e das interações binárias entre elas. Estabeleceram-se, ainda, diagramas triangulares, onde foram indicadas curvas de níveis. Os resultados da distribuição estereoespecífica demonstraram que, antes do rearranjo ao acaso, houve preferência do ácido oléico pela posição sn-2, enquanto que os ácidos palmítico e esteárico distribuíram-se principalmente pelas posições sn-1 e sn-3. Nos lipídios estruturados, os ácidos graxos saturados aumentaram sua participação na posição central do triacilglicerol, enquanto os ácidos graxos insaturados apresentaram diminuição nesta mesma posição. Para a estrutura cristalina foram determinados a dimensão fractal, o diâmetro e o número dos cristais, às temperaturas de 15, 20, 25 e 30ºC. Os números de cristais estiveram compreendidos entre 38 a 5245 e entre 33 a 3318, antes e depois da interesterificação, respectivamente. A dimensão fractal variou de 1,47 a 2,44 e de 1,35 a 2,59, antes e após a interesterificação, respectivamente. Os diâmetros médios dos cristais antes da interesterificação estiveram na faixa de 11,93 a 643,48m e, após a interesterificação, os valores variaram de 12,96 a 299,20m. Os lipídios estruturados apresentaram menor número de cristais e menores dimensões fractais que as misturas originais, com exceção da amostra que continha 2/3 de gordura de palma. / Structured lipids are compounds that can be synthesized by blending followed interesterification of fats and oils. These compounds, formed by rearrangement of medium and long chain tryacylglicerols show physical, chemical and nutritional characteristics different from the original lipids. They can also be considered nutraceuticals" because of their potentiality in preventing and treating illnesses. This is due to the present clinical advantages associated to the medium chain fatty acids (MCFA) and also, the particular structure of the lipidic molecule formed by the interesterification. Two lipid modification methods were used in this study: blending and interesterification. Refined palm oil, palm kernel oil and medium chain tryacylglicerols (Trigliceril CM) were used as raw material. Ten experiments were planned and carried out. A mathematical model using the special cubic type multiple regression was applied to the analytical responses obtained. The results were shown in triangular diagrams where the contour curves were traced. A correlation between the quantitative measures of the microscopic morphologic aspects and the physical characteristics of the lipids was also established. The following analysis were carried out: determination of softening and melting points, viscosity, consistency, solid fat content, stereospecific distribution of fatty acids by enzymatic hydrolysis technique, and crystal structure of samples obtained before and after chemical interesterification. The results show that the interactions that occurred amongst the three components were not significant in relation to the softening and melting points, the viscosity, and the consistency before interesterification, and the solid fat content before and after interesterification. The negative coefficients of the parameters analyzed show an antagonic effect, which is characteristic of eutectic interactions amongst fats. The softening and melting points depended on the palm and palm kernel fats, and on the interactions that occurred between the medium chain tryacylglicerols (MCT) and the palm and palm kernel fats. The viscosity depended on the palm and palm kernel fats and on the medium chain tryacylglicerols (MCT). The solid fat content depended on the palm and palm kernel fats and on the binary interactions between them. The results of the stereospecific distribution showed that, instead of a random distribution, oleic acid was preferably esterified at the sn-2 position, whereas palmitic and stearic acids were mainly distributed at the sn-1 and sn-3 positions. The saturated fatty acids in the structured lipids increased their participation in the tryacylglicerol central position, whereas the unsaturated fatty acids decreased their participation at the same position. Fractal dimension, crystal diameter, and crystal number at 15, 20, 25 and 30ºC were determined to analyze the crystal structure. Fractal dimension varied from 1,47 to 2,44 and from 1,35 to 2,59 before and after the interesterification reaction, respectively. The crystal number varied from 38 to 5245 and from 33 to 3318, before and after the interesterification reaction, respectively. The average diameter of the crystals before interesterification varied from 11,93 to 643,48m and, after interesterification, these values varied from 12,96 to 299,20m. Structured lipids showed a smaller crystal number and smaller fractal dimensions than the original mixtures, with exception of the sample containing 2/3 of palm oil.
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Integration of geospatial technologies into K-12 curriculum: an investigation of teacher and student perceptions and student academic achievementUnknown Date (has links)
The purpose of this study was to explore outcomes of a GIS/GPS integration process: to (a) examine student responses to GIS and GPS inclusion in their curriculum, (b) determine whether a relationship exists between inclusion of GIS into existing K-12 curriculum and student achievement, (c) examine the effectiveness of GIS professional development for teachers, and (d) evaluate teacher perceptions of the value of integrating GIS into their existing curricula. This study was quantitative and quasi-experimental in design. The samples consisted of 1,425 students from one middle school and 62 teachers from Palm Beach County School District. Two instruments were used in this study: student surveys and teacher feedback forms. Data from the student surveys indicated that students perceive their learning is enhanced by inclusion of GIS and GPS. Data from the teacher feedback forms revealed positive perceptions of the GIS/GPS program as an integrative tool for their existing curricula and a positive assessment of the GIS professional development training. The relationship between GIS instruction and student academic achievement was evaluated, measured by FCAT reading scores and final grades in science and social studies. The findings support the constructivist theory that students learn best when actively engaged in the process. In this study standardized FCAT reading test results and science and social studies grades corroborate the students' perceptions that GIS and GPS integration enhances their learning. Study results show FCAT reading scores were higher for GIS students than for non-GIS students. The research further indicated a significant increase in FCAT reading scores for non-native English speaking GIS students and a significantly higher average science grade for non-White GIS students. / The findings also show that students who had a greater frequency of GIS instruction had higher averages in science and social studies grades. Education reform requires bold initiatives and an organizational culture supportive of innovative ideas. The structured model for development and implementation of GIS in the K-12 public school system presented at the end of this study includes collaboration between district leadership, administrators and teachers, and a comprehensive approach to professional development. / by Donna L. Goldstein. / Thesis (Ph.D.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.
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Coordination spatio-temporelle des regulateurs du reseau branche d’actine dans les structures motiles / Spatio-temporal coordination of branched actin network regulators in motile structuresMehidi, Mohamed El Amine 13 December 2016 (has links)
La motilité cellulaire est un processus intégré essentiel à de nombreux phénomènes physiologiques tels que la formation du cône de croissance et la plasticité synaptique. Des dérégulations de la motilité cellulaire peuvent être à l’origine de la formation de métastases ou de pathologies neuropsychiatriques comme la schizophrénie et l'autisme. La compréhension des mécanismes régulant la migration cellulaire est donc un enjeu majeur. La motilité cellulaire repose sur la formation de diverses structures constituées de réseaux d’actine branchés telles que le lamellipode. La formation du lamellipode nécessite l’intervention de protéines régulatrices de l’actine telles que Rac1 et les complexes Wave et Arp2/3. Grâce à l’utilisation de suivi de protéine unique, nous avons pu comprendre comment la coordination spatio-temporelle de ces régulateurs contrôle la formation et la morphologie des lamellipodes de cellules migrantes. Nous avons ainsi découvert que l’activation et la localisation du complexe Wave étaient régulées de manière enzymatique mais également mécanique. Dans une première étude, nous avons montré que la RhoGTPase Rac1 active le complexe Wave spécifiquement à l’extrémité du lamellipode. Dans une seconde étude, nous avons révélé que la localisation du complexe Wave est régulée par la dynamique des filaments des réseaux branchés d’actine. Ces données soulignent l’importance du complexe Wave dans la formation du lamellipode et révèlent l’existence d’une régulation mécanique de la localisation du complexe Wave. / Cell motility is an integrated process involved in critical phenomena such as axonal pathfinding and synaptic plasticity. Dysregulation of cell motility can induce metastasis and abnormal spine shapes observed in neuropsychiatric disorders like autism and schizophrenia. Therefore it is essential to understand how cell motility is regulated. Cell motility requires the formation of branched actin networks propelled by actin polymerization that lead to the formation of membrane protrusions such as the lamellipodium. Several actin regulatory proteins are involved in this process, such as Rac1 and the WAVE and ARP2/3 complexes. Using single protein tracking, we revealed key phenomena concerning the spatio-temporal regulation of lamellipodium formation by actin regulatory proteins. We found that the localization and activation of the WAVE complex was enzymatically regulated, but also mechanically. First, we showed that the Rac1 RhoGTPase activates the WAVE complex specifically at the tip of the lamellipodium. We also showed that WAVE complex localization is regulated by the dynamics of branched-network actin filaments. This study confirms the crucial role of the WAVE complex in lamellipodium formation and reveals the existence of a mechanical regulation of the localization of this complex in the cell.
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Fluorescence nanoscopy in three dimensions / Fluoreszenz-Nanoskopie in drei DimensionenGeisler, Claudia 15 December 2009 (has links)
No description available.
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Dreidimensionale Diagnostik der großskaligen Zirkulation der Tropo- und Stratosphäre / Three-dimensional diagnostics of the large-scale circulation in the troposphere and stratosphereJaiser, Ralf January 2013 (has links)
In dieser Arbeit werden Konzepte für die Diagnostik der großskaligen Zirkulation in der Troposphäre und Stratosphäre entwickelt. Der Fokus liegt dabei auf dem Energiehaushalt, auf der Wellenausbreitung und auf der Interaktion der atmosphärischen Wellen mit dem Grundstrom. Die Konzepte werden hergeleitet, wobei eine neue Form des lokalen Eliassen-Palm-Flusses unter Einbeziehung der Feuchte eingeführt wird. Angewendet wird die Diagnostik dann auf den Reanalysedatensatz ERA-Interim und einen durch beobachtete Meerestemperatur- und Eisdaten angetriebenen Lauf des ECHAM6 Atmosphärenmodells.
Die diagnostischen Werkzeuge zur Analyse der großskaligen Zirkulation sind einerseits nützlich, um das Verständnis der Dynamik des Klimasystems weiter zu fördern. Andererseits kann das gewonnene Verständnis des Zusammenhangs von Energiequellen und -senken sowie deren Verknüpfung mit synoptischen und planetaren Wellensystemen und dem resultierenden Antrieb des Grundstroms auch verwendet werden, um Klimamodelle auf die korrekte Wiedergabe dieser Beobachtungen zu prüfen. Hier zeigt sich, dass die Abweichungen im untersuchten ECHAM6-Modelllauf bezüglich des Energiehaushalts klein sind, jedoch teils starke Abweichungen bezüglich der Ausbreitung von atmosphärischen Wellen existieren. Planetare Wellen zeigen allgemein zu große Intensitäten in den Eliassen-Palm-Flüssen, während innerhalb der Strahlströme der oberen Troposphäre der Antrieb des Grundstroms durch synoptische Wellen verfälscht ist, da deren vertikale Ausbreitung gegenüber den Beobachtungen verschoben ist.
Untersucht wird auch der Einfluss von arktischen Meereisänderungen ausgehend vom Bedeckungsminimum im August/September bis in den Winter. Es werden starke positive Temperaturanomalien festgestellt, welche an der Oberfläche am größten sind. Diese führen vor allem im Herbst zur Intensivierung von synoptischen Systemen in den arktischen Breiten, da die Stabilität der troposphärischen Schichtung verringert ist. Im darauffolgenden Winter stellen sich barotrope bis in die Stratosphäre reichende Änderungen der großskaligen Zirkulation ein, welche auf Meereisänderungen zurückzuführen sind. Der meridionale Druckgradient sinkt und führt so zu einem Muster ähnlich einer negativen Phase der arktischen Oszillation in der Troposphäre und einem geschwächten Polarwirbel in der Stratosphäre.
Diese Zusammenhänge werden ebenfalls in einem ECHAM6-Modelllauf untersucht, wobei vor allem der Erwärmungstrend in der Arktis zu gering ist. Die großskaligen Veränderungen im Winter können zum Teil auch im Modelllauf festgestellt werden, jedoch zeigen sich insbesondere in der Stratosphäre Abweichungen für die Periode mit der geringsten Eisausdehnung. Die vertikale Ausbreitung planetarer Wellen von der Troposphäre in die Stratosphäre ist in ECHAM6 mit sehr großen Abweichungen wiedergegeben. Somit stellt die Wellenausbreitung insgesamt den größten in dieser Arbeit festgestellten Mangel in ECHAM6 dar. / In this study concepts for the diagnostics of the large-scale circulation in the troposphere and the stratosphere are developed. Therefore the energy budget, wave propagation and the interaction between waves and the mean flow are analyzed. A corresponding set of diagnostic methods is derived. Furthermore a new type of localized Eliassen Palm Fluxes including moisture fluxes is introduced. These diagnostic methods are then applied to the ERA-Interim reanalysis and to a run of the ECHAM6 atmospheric model forced with observed sea surface temperatures and sea ice data.
The diagnostics of the large scale circulation are useful to enhance the understanding of the climate system dynamics. Furthermore the knowledge of the relation between energy sources and sinks, atmospheric waves on planetary and synoptic scales and their forcing of the mean flow is applicable to validate global climate models. The results presented here show small deviations in terms of the energy balance in ECHAM6 but large discrepancies in terms of wave propagation. On the one hand Eliassen Palm fluxes connected to planetary waves are generally too strong. On the other hand the mean flow forcing within upper tropospheric jet streams by synoptic scale waves does not agree with observations, since the vertical propagation is shifted.
A second part of this study analyses the influence of Arctic sea ice anomalies at the sea ice minimum in August/September on atmospheric conditions. Strong positive temperature anomalies with their maximum at the surface are observed. In autumn they lead to intensified synoptic scale systems, because of a reduced atmospheric vertical stability. A large-scale barotropic circulation pattern up to the stratosphere appears in winter related to previous late summer sea ice changes. A reduced meridional pressure gradient leads to a pattern related to a negative phase of the Arctic Oscillation in the troposp
here as well as related to a weaker stratospheric polar vortex.
The same analysis performed with an ECHAM6 model run shows a too small warming of Arctic latitudes. While tropospheric changes in the Arctic are covered by the model to some degree, the stratosphere shows large discrepancies in reproducing the observed changes in the low ice period. The vertical propagation of planetary waves from the troposphere into the stratosphere is reproduced with large differences. Accordingly this study shows the largest errors in ECHAM6 related to atmospheric wave propagation.
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The place and role of tradition in the Nigerian novel : the examples of Amos Tutuola and John MunonyeDatondji, Cooyi Innocent January 1984 (has links)
The purpose of this study was to investigate the place and role of tradition in the Nigerian novel. For many years, in my attempt to find out some of the causes of the difficulties our countries are facing, I have come to suspect our traditions as being one major cause. In fact, this study has shown that our traditions, though supposedly destroyed by colonization, have retained many of their aspects which are cunningly at work in our societies, together with European traditions.Because the essential role of tradition is to define the present, we need to find out more about our traditions in order to know how we can best explore them for the advancement of our countries in a changing world.
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Produção e avaliação físico-química da aguardente do fruto da palma forrageira (Opuntia ficus - indica Mill). / Production and physical-chemical evaluation of the aguardente of the fruit of the forage palm (Opuntia ficus - indica Mill).ROCHA, Aleksandra Silva. 16 October 2018 (has links)
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Previous issue date: 2008-02 / O futuro das zonas áridas e semi-áridas do mundo depende do desenvolvimento sustentável de sistemas agrícolas baseados numa seleção adequada de cultivos. Os cultivos mais apropriados são os que podem suportar condições de falta de água, altas temperaturas, solos pobres que exijam poucos insumos energéticos, e que sejam de fácil manejo no plantio, para que proporcionem alimento e forragem para a agricultura de subsistência, além do mais é importante que o produto e/ou subproduto sejam apreciados e tenham valor no mercado internacional. Uma das formas de valorizar a cultura da palma forrageira e contribuir para o desenvolvimento sustentável da região nordestina é utilizar o fruto (figo-da-índia) como matéria-prima para produzir fermentado (vinho) e aguardente, produtos que apresentam longa vida de prateleira e têm altos índices de comercialização. Trabalho foi realizado com o objetivo de estudar a produção e avaliar a composição físico-química da aguardente da fruta da palma forrageira confrontando com a legislação vigente para bebidas. A metodologia consistiu na produção dos fermentados do fruto integral (casca e polpa) utilizando-se de um reator em operação batelada na temperatura de 30 °C e inoculando-se com levedura comercial e selecionada de algaroba. Os fermentados foram destilados em alambique de cobre e separado as frações: cabeça (10%), coração (80%) e cauda (10%). Foram realizadas análises de °Brix, acidez total (g/lOOmL), pH, concentração de etanol (%v/v), metanol, acetaldeído, ésteres (g/lOOmL) álcoois superiores n-propanol, isobutanol, isoamílico (g/lOOmL) do destilado e fermentado, confrontando-se as análises físico-químicas das aguardentes dos destilados dos fermentados utilizando-se da levedura comercial e selecionada de extrato de
algaroba. Verificou-se que os produtos se encontram com as características exigidas pela
legislação brasileira acerca de bebida, ou seja, concentração de etanol na aguardente de 34,9 e 46,2% °GL (% v/v), respectivamente. Os componentes secundários estão todos abaixo do máximo permitido, com exceção dos álcoois superiores do inoculo da levedura selecionada do caldo da algaroba o qual esteve um pouco acima do permitido. A produção da aguardente aproveitando o fruto integral figo-da-índia é uma alternativa promissora e tecnicamente viável. / The future of semi arid and arid regions of the world depends on sustainable development of agricultural systems based on adequate crop selection. The most appropriate crops are those than can support conditions of lack of water, high temperatures, poor soils, demand little energy inputs, are easily managed in the field, in order to provide food and forage for
subsistence agriculture. It is also important that the product and / or sub products are liked and that it has value in the international market. One of the ways of increasing the value of
prickly pear cactus and to contribute to sustainable development in the northeast region is to use the tuna fruit as an ingredient to producc fermented (wine) and distilled spirits, products that have a long shelf life and high marketing indexes. This study was undertakcn vvith the objective of studying the production of fermented whole fruit (skin and flesh) products using a reactor in a agitator operation at the temperature of 30 °C and inoculating with a commcrcial yeast and a selected 'algaroba' yeast. The fermented products were distilled in a copper still and separatcd into the following parts: hcad (10%), heart (80%) and juice (10%). The following °Brix analysis were carried out: total acidity (g/100 mL), pH, ethanol concentration (% v/v), methanol, acetaldehyde, esters (g/100 mL), superior alcohols n-propanol, isobutanol, isoamilico (g/100 mL) of the distilled and fermented products, comparing them with the physical-chemical analysis of distilled and fermented spirits, using commercial and selected 'algaroba' yeasts. It was verified that the products have the characteristics required by Brazilian alcohol lcgislation, specifically, ethanol concentration in rum of 34.9 and 46.2% °GL (% v/v), respectively. The secondary components are ali below the maximum permitted, with the exception of superior alcohols of yeast inoculants selected from the 'algaroba' juice which were a bit above the permitted levei. The production of spirits using the whole prickly pear fruit is a promising alternative and is technically viable.
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