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Cheng, Terry Hsu-Huang. "Bonsai." AUT University, 2009. http://hdl.handle.net/10292/964.
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This thesis includes an introduction to my bonsai container design along with a history of bonsai, discussion of the philosophies of key bonsai masters, the details of two bonsai containers based on Japanese courtyard culture and Japanese architectural philosophy. It also documents the design process of all 1:1 scale Bonsai containers and the exhibition space, which includes bonsai planted in each container on the presentation day.
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Manyakara, Bongai. "Antioxidant properties of Plumbago auriculata Lam / Bongai Manyakara." Thesis, North-West University, 2009. http://hdl.handle.net/10394/4421.
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Parkinson's disease, a disease first described by James Parkinson two centuries ago is one of the most common neurodegenerative diseases. The prominent feature of this disease is the selective degeneration of dopaminergic neurons in the substantia nigra of the midbrain resulting in a decrease in dopamine levels in the brain. The substantia nigra appears to be an area of the brain that is highly susceptible to oxidative stress. Supplementation with antioxidants may protect the neurons from the damaging effects of oxidation by reacting with oxygen radicals and other reactive oxygen species (ROS).
The aim of this study was to investigate the antioxidant properties of the leaves of the plant Plumbago auriculata and to evaluate its antioxidant activity on rats. Four solvents; petroleum ether, dichloromethane, ethyl acetate and ethanol were used successively to extract substances from the leaves of the plant using the soxhlet apparatus. The Thiobarbituric Acid-Reactive Substances (TBARS) and the Nitro-Blue Tetrazolium (NBT) assays were performed to evaluate antioxidant activity. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was done to determine the relative toxicity of each extract. The results showed that the ethyl acetate and the ethanol crude extracts had significantly higher antioxidant activity than the petroleum ether and the dichloromethane extracts.
In the TBARS assay the ethanol and ethyl acetate extracts each at 2.5 mg/ml reduced malondialdehyde (MDA) levels significantly (p < 0.001) compared to the toxin (H²O² + FeCl³ + Vit. C). Ethanol and ethyl acetate extracts each had values of 0.0058 nm MDA/mg tissue and 0.0067 nm MDA/mg tissue respectively in comparison to the toxin's 0.0257 nm MDA/mg tissue. Results of the NBT assay results showed that at concentration ranges of 0.625 -2.5 mg/ml, the ethyl acetate and ethanol extracts had the best (p < 0.001) superoxide scavenging activity compared to the toxin (KCN). The ethyl acetate and petroleum ether extracts significantly inhibited the proliferation of HeLa cells by 11.52 % (p < 0.05) and 27.3 % (p < 0.001) respectively at 10 mg/mL, compared to the control when evaluated with the MTT assay. Although the MTT assay results showed toxicity with the 10 mg/ml concentration of the ethyl acetate extract, this extract is one of the two extracts that had the most promising antioxidant activity. It is possible that different compounds in each extract contributed to the antioxidant activity and toxicity. Therefore, the ethyl acetate extract was put through bioassay-guided fractionation using column chromatography to isolate antioxidant compounds.
Two compounds, PS and OS were isolated. 13C NMR, DEPT 13C NMR, 1H NMR and FT-IR were used to characterize 'the structures of the isolated compounds. PS was found to be β-sitosterol, while OS was proposed to be β-carotene. OS reduced MDA levels significantly at all concentrations. At 2.5 mg/ml, the reduction in MDA was almost to the level of the control. The isolated compounds are common in most plants and are known to have antioxidant activity. Further fractionation needs to be done to isolate less common compounds.Thesis (M.Sc. (Pharmaceutical Chemistry))--North-West University, Potchefstroom Campus, 2010.
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Pujatti, Leonardo. "A interface digital nas digigrafias de Maria Bonomi." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/93/93131/tde-16052018-110725/.
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Este trabalho trata da relação entre arte e tecnologia e das possibilidades de representação utilizadas nas digigrafias da artista plástica Maria Bonomi, nascida na Itália, mas radicada em São Paulo desde a infância, e que atua como gravadora, pintora, professora, muralista, figurinista, cenógrafa etc., com reconhecido destaque por suas gravuras e pelas obras de grande porte em espaços públicos e que apresenta novas interfaces estéticas com o uso das tecnologias digitais e eletrônicas, potencializando a imaginação e as mediações simbólicas. Esta tese utilizou-se da pesquisa bibliográfica e da coleta de depoimentos da artista para sustentar as discussões sobre os novos caminhos da arte através da utilização dos meios digitais, buscando compreender em que medida o computador contribui na ampliação da potencialidade das técnicas tradicionais de criação artística possibilitando articulações e mediações entre a tecnologia e a arte.This work deals with the relationship between art and technology and the possibilities of representation used in the digigraphies of the plastic artist Maria Bonomi, born in Italy, but based in São Paulo since childhood, and who acts as a recording company, a painter, a teacher, a muralist, scenographer, etc., recognized by his engravings and large works in public spaces, which presents new aesthetic interfaces with the use of digital and electronic technologies, enhancing imagination and symbolic mediations. This thesis was based on the bibliographical research and the collection of testimonies of the artist to support the discussions about the new paths of art through the use of digital media, trying to understand to what extent the computer contributes to the amplification of the potential of traditional techniques of artistic creation enabling articulations and mediations between technology and art.
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Nhedo, Marcela Matos 1972. "O pensamento xilografico na obra de Maria Bonomi." [s.n.], 2002. http://repositorio.unicamp.br/jspui/handle/REPOSIP/285093.
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Orientador: Daisy Valle M. Peccinini de AlvaradoDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Artes
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Resumo: A necessidadede focalizar o objeto de estudo demanda um conhecimento aprofundado da obra de Maria Bonomi. Por esta razão, a estruturação desta dissertaçãose apoiou na pesquisa de campo, para o desenvolvimento de uma biografia seletiva comentada pela relevância dos acontecimentos em sua vida artística e para a catalogação de obras, em sua maioria inéditas até 1950, e um capítulo voltado à análise destas obras e de outras de diferentes períodos até a atualidade. Esta pesquisa permite uma reflexão de como se estruturou o programa repertorial da artista e sobretudo, como se formou o chamado "pensamento xilográfico" em sua obra
Resume: Le besoin de focaliser l'objet d'étude part d'une demande de connaitre avec profondeur l'oeuvre de Maria Bonomi. Pour cette raison, la structuration de cette these s'est appuyée à la recherche historique investigative, dans le développement d'une biografie selective commentée par la priorité des événements de sa vie artistique et par l'ordination des oeuvres dont la plupart inédites jusqu'en 1950 et un chapitre sur l'analyse de ces oeuvres-ci et d'autres de périodes différentes jusqu'à l'actualité. Cette recherche permet une réflexion: comment le programm répertoire visuel de l'artiste s'est structuré et surtout comment la nomination pensée xilographiques'est imposée
Mestrado
Mestre em Artes
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Bononi, Judy. "Analysis of the expression and function of chicken protocadherin 1 in neural crest cell migration and peripheral nervous system formation." Diss., Montana State University, 2007. http://etd.lib.montana.edu/etd/2007/bononi/BononiJ0807.pdf.
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The necessary steps of development from a single cell to a multi-celled functional organism are complex. Many molecules have been identified and their roles characterized in this process. One interesting population of cells includes the highly migratory neural crest cells (NCCs) unique to the vertebrate embryo and existing transiently during early embryonic development. The NCCs migrate along specific pathways at specific timepoints, stop at target locations, differentiate and give rise to a variety of cell types and tissues. Trunk NCCs must choose between two different migratory pathways: the ventral route, giving rise to neurons and glia of the dorsal root ganglia (DRG), sympathetic ganglia (SG), Schwann cells of the ventral root (VR); or the dorsolateral pathway, giving rise to melanocytes. Although many aspects of neural crest migration have been elucidated, cessation of migration and subsequent differentiation at target structures is not clearly defined. One family of molecules involved in various steps of NCC migration is the cell-cell adhesion molecules, the cadherins. To investigate the involvement of cadherins in NCC migration and differentiation during development using the avian model system, a combination of experiments and techniques including a library screen, in situ hybridization, in ovo electroporation, immunohistochemical and immunofluorescence staining as well as live time-lapse confocal imaging were performed. Results from these experiments produced the discovery and isolation of a novel molecule in the family of cadherin adhesion molecules, chicken protocadherin-1 (cPcdh1). Expression analysis showed cPcdh1 expressed in migrating NCCs, the DRG, SG and Schwann cells along the VR. A distinct expression pattern showed cPcdh1 along the periphery of the DRG, where crest cells are in an undifferentiated and mitotically active state. Further testing with deletion constructs and siRNA demonstrated when cPcdh1 function is inhibited, a greater percentage of cells migrate to the SG and VR at the expense of the DRG. Time-lapse confocal imaging showed cPcdh1 cells having an elongated cell shape with contact primarily being formed with neighboring cells along the periphery and longer cell-cell contact than observed in the control. Collectively, the results provide evidence for cPcdh1 involvement in NCC migration arrest and DRG formation.
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GUERRA, Lúcia Helena Barbosa. "Xangô rezado baixo. Xambá tocando alto : a reprodução da tradição religiosa através da música." Universidade Federal de Pernambuco, 2010. https://repositorio.ufpe.br/handle/123456789/1112.
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Previous issue date: 2010Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
A construção dessa dissertação é fruto de pesquisa realizada ao longo dos últimos quatro anos no Terreiro Santa Bárbara da Nação Xambá, localizado na cidade de Olinda/PE. Busquei entender como os jovens, representados aqui pelo grupo musical Bongar, se utilizam da música para evidenciar a importância religiosa da sua Nação, tida por muitos pesquisadores como extinta. Para compreender as transformações ocorridas no terreiro ao longo da última década; dentre elas a conquista do título de Quilombo Urbano; procurei resgatar a história da Nação Xambá, desde a sua chegada em Pernambuco na década de 20 até os dias de hoje. Investiguei no contexto desta comunidade a relação entre religião e festa, que por sua vez conecta dois universos dialéticos: o sagrado e o profano. Para pensar estes laços, elegi festejos que fazem parte do calendário do terreiro, objetivando identificar elementos do sagrado interagindo com elementos do profano, além de observar as funções sociais das festas dentro do âmbito da Nação Xambá
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Oliveira, Alecsandra Matias de. "Poética da Memória: Maria Bonomi e epopéia paulista." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/27/27160/tde-23042009-104853/.
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O presente estudo aborda as relações existentes entre a memória e a arte, registradas através de monumentos arquitetônicos na cidade de São Paulo, especialmente, no âmbito da arte contemporânea. Elege como instrumental de pesquisa a história da arte e seus desdobramentos estéticos, tendo como foco de análise a poética de memórias de Maria Bonomi uma das mais importantes artistas do cenário nacional. O painel Epopéia Paulista, construído a partir de ateliêresidência, em abril de 2004, no espaço expositivo do Museu de Arte Contemporânea da Universidade de São Paulo (MAC USP) e que hoje se encontra no corredor de ligação entre o Metrô e a Companhia Paulista de Trens Metropolitanos (na Estação da Luz) serve como obra-referência na criação e no processo de narrativas de memórias de diversas etnias em São Paulo. A pesquisa toma Epopéia Paulista como motivação para o estudo das questões latentes no fazer artístico atual. Intenta-se um mapeamento das ligações interdisciplinares entre arte e memória a partir do registro de discussões envolvendo artistas, críticos, obras e instituições. Da análise de Epopéia Paulista emergem elementos intrínsecos à arte contemporânea, constituindo uma poética de memórias que evoca a história da cidade de São Paulo e de seus habitantes.This study deals with the relations between memory and art, especially the contemporary art seen in architectural monuments in the city of São Paulo. With this aim, the art history and its aesthetic developments are used as a tool for the research, focusing on the poetics of memories by Maria Bonomi one of the most important artists of the national artistic circuit. The Epopéia Paulista panel (São Paulos Epic Panel), which was built in a residence-studio in April 2004 in the exhibition room of the Museum of Contemporary Art of the University of Sao Paulo (MAC USP), and currently located in the passageway that joins the subway (Luz Station) to the São Paulos Company of Metropolitan Trains, works as a reference artwork to the creation and process of narratives of memories of the different ethnic groups in São Paulo. The research uses the Epopéia Paulista as motivation for the study of current issues in the artistic field. The intention here is to map the interdisciplinary relations between art and memory using records of debates involving artists, critics, artworks and institutions. Elements that are intrinsic to the contemporary art arise from the analysis of the Epopéia Paulista, constituting a poetics of memories that evokes the history of the city of São Paulo and its inhabitants.
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Koch, Veronique. "The Spatial Ecology of Black Groupers (Mycteroperca bonaci) in the Upper Florida Keys." Scholarly Repository, 2011. http://scholarlyrepository.miami.edu/oa_theses/266.
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Black groupers (Mycteroperca bonaci) are a critical component of coral reef ecosystems as well as South Florida fisheries. It is therefore of great concern that their essential fish habitat has not yet been fully defined. Using an interdisciplinary approach, the ecology of black groupers was characterized in the Upper Florida Keys. The first part of this study utilized acoustic telemetry. Self-contained acoustic receivers were placed in an array around Conch Reef and tracked 16 tagged black groupers for 483 days. Patterns of movement behavior and habitat usage were modeled using presence-absence data. The capture-recapture program MARK was used to estimate the model parameters. It was found that spur and groove habitat was the most frequented habitat during the study period, along with artificial reef structure. Movement behavior followed patterns according to changes in seawater temperature, as well as sunrise and sunset. The second part of the study used anthropological methods based on political ecology to investigate the interactions of the black grouper population of the Upper Keys with the human residents and visitors to the area. In-depth life and work histories were conducted with stakeholders to determine the stakeholder groups involved in the political ecology of this natural resource. Seven stakeholder groups and eight subgroups interviewed over a three-month period. Paradoxically, black groupers remain a part of Upper Florida Keys culture, and demand for them has lead to increased rates of imports from other countries and fish fraud still prevails. Conducting ecological research along side an anthropological study proved to be key for obtaining a full overview of the ecology of black groupers. The study of stakeholder local knowledge can provide important information for telemetry studies, as well as inform resource managers seeking to establish enforceable regulations. The synthesis of this study showed that spatial management would be an appropriate tool for protecting black groupers juveniles, given their strong site fidelity.
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Hermann, Caroll. "Integral ecopsychological investigation of bonsai principles, meaning and healing." Thesis, University of Zululand, 2013. http://hdl.handle.net/10530/1388.
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A thesis submitted to the Faculty of Arts in fulfilment of the requirements for the Degree of Doctor of Philosophy in the Department of Psychology at the University of Zululand, South Africa, 2013.Art therapy is very popular amongst therapists, and Bonsai art adds another dimension to the intervention stratagem. One aspect of an intervention strategy is to reduce the burden of mental illness and related conditions. Bonsai as an intervention combines meditation, spirituality, responsibility and the ability to express oneself through this timeless art. An international study was conducted of the habits, health and spirituality of bonsai practitioners. Participants completed the Spirituality Scale, Patient Health Questionnaire and the Quality of Life Scales, as well as a questionnaire about their interest in Bonsai. Results indicated that although the participants were not necessarily healthier than the general population, they experienced peace by being actively involved in Bonsai. Bonsai is proposed as a new expanded category of supportive therapeutic mechanism, along with an elaboration of expressive therapeutic mechanisms such as when working in groups,such as hospitals,old age homes and prisons.
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Cruz, Quental Jamily. "Comportamento geomecânico dos solos de fundações das torres da linha de transmissão Recife II/Bongi." Universidade Federal de Pernambuco, 2008. https://repositorio.ufpe.br/handle/123456789/5315.
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Previous issue date: 2008O crescimento econômico, o aumento da oferta de energia e o crescimento da concentração da população em pólos urbanos são fatores que contribuíram significativamente para o mercado de energia elétrica no país. Neste cenário torna-se necessário um avanço nas técnicas de implantação de sistemas de transmissão de energia. Analisando as técnicas atualmente empregadas na prática de engenharia de fundações em torres de Linhas de Transmissão, nota-se a necessidade de avanços nas técnicas utilizadas na investigação geotécnica dos solos. Realizou-se um estudo de caso em três estruturas (T1A, T2A e T3A) da Linha de Transmissão Recife II / Joairam, localizadas no município de Jaboatão dos Guararapes/PE. As coordenadas geográficas dos locais das estruturas serviram para identificar as unidades geológicas e as classes pedológicas, topografia e vegetação. Foram realizados ensaios de caracterização física (granulometria, densidade real, limites de consistência), química (determinação do pH); teor de sais dissolvidos, cátions trocáveis e condutividade elétrica), edométricos simples e duplos e cisalhamento direto (com e sem inundação). A avaliação da capacidade de carga dos solos de fundação considerou os esforços de compressão (Vesic,1975) e tração (Método do Tronco de Cone e Grenoble (1968)). Os solos analisados na cota de fundação apresentaram características arenosas, tendo a fração argila sido classificada como CL, exceto para a estrutura T2A que foi classificada como SM. São ácidos, tem baixa capacidade de troca de cátions, em predominância, indicando a presença de caulinita, apresentam características de dispersividade. A compressibilidade cresce e há indicação de solos colapsíveis abaixo das estruturas T2A e T3A quando o teor de umidade cresce. Os ângulos de atrito dos solos variam de 29º a 35º, havendo pouca influência com a inundação em cada solo. Entretanto o aumento de umidade causa uma significativa redução na coesão de 49 a 0 kPa (T2A). A análise da capacidade de carga á tração apresentou fatores de seguranças críticos ao utilizar o método do Tronco de Cone e satisfatórios com a aplicação da metodologia de Grenoble (1968)
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ISIDRO, E. G. C. "Modelos Simples de Lemaitre - Tolman - Bondi (LTB)." Universidade Federal do Espírito Santo, 2015. http://repositorio.ufes.br/handle/10/7459.
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Previous issue date: 2015-05-07O modelo padrão atual da cosmologia, o modelo ΛCDM (Λ-Cold Dark Matter), está baseada nas soluções homogêneas de Friedmann-Lemaître-Robertson-Walker (FLRW) das equações de Einstein. As características da Cosmic Microwave Background (CMB) e da formação de estrutura em grandes escalas, são estudadas através da teoria das perturbações cosmológicas no fundo homogêneo e isotrópico. No entanto, nos últimos quinze anos, modelos cosmológicos inomogêneos "simples"que são generalizações do modelo cosmológico FLRW ganharam interesse na comunidade astrofísica e têm sido utilizados para estudar fenômenos cosmológicos. Alguns autores demonstraram que estes modelos inomogêneos com simetria esférica e com fonte de poeira podem reproduzir um bom ajuste para os dados de supernovas do tipo Ia (SNIa) e a posição do primeiro pico da CMB. Estes modelos sugerem que a aparente expansão acelerada do Universo não é causada pela gravidade repulsiva devido à energia escura, mas é sim o resultado das inomogeneidades na distribuição da matéria. Nesta dissertação, os modelos inomogêneos do Universo são investigados na base da métrica de Lemaître-Tolman-Bondi (LTB), o que representa uma solução com simetria esférica para poeira. Dois modelos particulares são estudados: a evolução parabólica com tempo de Big Bang inomogêneo e a evolução hiperbólica com curvatura fraca e tempo de Big Bang constante. As propriedades de cada um destes modelos são investigadas em detalhe, da forma mais analítica possível. Ambos modelos são confrontados com observações astrofísicas da amostra Union2.1 SNIa. Conclui-se que esses modelos podem ser um ponto de partida para desenvolver modelos mais realistas. Portanto, a solução de LTB é capaz de explicar a relação observada entre a distância de luminosidade e o desvio para o vermelho de supernovas sem a necesidade da energia escura quando a inomogeneidade é da forma de um vazio ou quando se tem uma colina centrada no observador com a suposição adicional de que o Universo fora do vazio ou fora da colina é aproximadamente descrito pelo modelo de Einstein-de Sitter homogéneo.
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Deremetz, Aurélie. "Implication de la protéine SG1 dans le maintien des épigénomes chez Arabidopsis thaliana." Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLS119/document.
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La chromatine est le support de l’information génétique et sa structure, ainsi que son activitétranscriptionnelle, peuvent être modulées par des modifications épigénétiques. Le maintien des marquesrépressives telles que la méthylation de l’ADN et des histones, hors du corps des gènes, est nécessairepour le bon développement de la plante. Chez Arabidopsis thaliana, le mutant sg1 présente des défautsdéveloppementaux sévères caractéristiques de mutants affectés dans des mécanismes épigénétiques. Nousavons montré que le phénotype de sg1 est causé par une hyperméthylation CHG et H3K9me2 dans denombreux gènes. En effet, SG1 contrôle la transcription de l’histone déméthylase IBM1 et lesmodifications de l’épigénome observées chez sg1 sont dues à une dérégulation de IBM1. Nous avonsidentifié sept protéines partenaires de SG1, dont certaines se lient aux marques chromatiniennes. Nousavons réalisé un crible suppresseur qui a permis d’identifier FPA, une protéine régulant lapolyadénylation de certains transcrits, comme acteur impliqué dans le contrôle des cibles de SG1, dontIBM1. Nos résultats montrent que le complexe SG1 régule la transcription de ses cibles en influençant,par un mécanisme encore inconnu, le choix du site de polyadénylation, en lien avec les marqueschromatiniennes présentes aux locus cibles. D’autre part, certaines épimutations induites par la mutationsg1 peuvent être maintenues pendant plusieurs générations. Pour rechercher un lien entre méthylation desgènes et conséquences phénotypiques, nous avons caractérisé des épimutations liées à un défaut dedéveloppement de la fleur et identifié un certain nombre de gènes candidats potentiellement responsablesdu phénotype. Les résultats obtenus au cours de ma thèse ont contribué à préciser le rôle joué par lecomplexe SG1 et à comprendre le lien entre celui-ci et les marques épigénétiquesChromatin is known to contain the genetic information and its structure and transcriptionalstate can be regulated by epigenetic modifications. Repressive marks such as DNA and histonesmethylation needs to be kept away from gene bodies to enable the proper development of the plant. InArabidopsis thaliana, sg1 mutants show a range of severe developmental defects similar to thoseobserved in mutants affected in epigenetic pathways. We have shown that sg1 mutant phenotype iscaused by an increase of CHG and H3K9me2 methylation in many gene bodies. Indeed, SG1 regulatesthe histone demethylase IBM1 transcription and the impairment observed in sg1 mutant epigenomes iscaused by IBM1 misregulation. We found seven proteins interacting with SG1, among which somepartners are able to bind chromatin marks. Through a suppressor screen we identified FPA, alreadyknown to regulate the polyadenylation of some transcripts, as a player involved in SG1 targetsregulation, including IBM1. Our results show that the SG1 complex regulates target genes transcriptionby affecting polyadenylation site choice, in a way that remains to be determined, in a chromatin marksdependent manner. We also found that some of the sg1-induced epimutations can be maintained throughseveral generations. To investigate the link between gene body methylation and phenotypicconsequences, we have characterized epimutations related to a defect in floral development andidentified some candidate genes potentially responsible for the floral phenotype. Thus, our resultscontributed to clarify the role of SG1 and to understand its connection with epigenetic marks
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Dramane, Boni. "Précipitation électrostatique de particules submicroniques par décharge à barrière diélectrique : étude électrique, granulométrique et aérodynamique." Poitiers, 2009. http://theses.edel.univ-poitiers.fr/theses/2009/Dramane-Boni/2009-Dramane-Boni-These.pdf.
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Nous avons, dans le cadre de ce travail, développé la Décharge à Barrière Diélectrique (DBD) dans deux électrofiltres de géométries différentes. L'un des électrofiltres est de configuration Fil -Cylindre et l'autre de configuration Plan-Plan. Le premier volet de l'analyse de la précipitation électrostatique a consisté à déterminer l'efficacité de collecte des électrofiltres. Les résultats obtenus ont montré que l'utilisation de la DBD pour la précipitation donnait non seulement de très bons résultats en configuration Fil-Cylindre, mais également en configuration Plan-Plan (plus de 99% d'efficacité). Le second volet de notre étude a été consacré à la caractérisation des phénomènes EHD à l'intérieur des électrofiltres DBD à l'aide de moyens métrologiques optiques. Les résultats ont montré que le vent électrique a une influence minime sur la précipitation. En dehors du processus de génération du vent électrique dû à la différence de rayon de courbure entre les électrodes, il semblerait que les streamers soient impliqués dans le phénomène de précipitation. D'un point de vue organisationnel, ce travail s'articule autour de quatre chapitres. Dans le premier chapitre, nous présentons la précipitation électrostatique comme un outil de dépollution de l'air. Le deuxième chapitre est consacré à la caractérisation électrique des électrofiltres. Le troisième chapitre aborde l'analyse des performances granulométrique des électrofiltres. Enfin, le quatrième chapitre traite l'aspect EHD des phénomènes opérant à l'intérieur des électrofiltresIn this work, we developed a Dielectric Barrier Discharge (DBD) in two opposite configurations of ESP. One of them is based on Wire-to-Cylinder configuration; the second is on Plate-to-Plate configuration. The first step of our analysis of the electrostatic precipitation was the evaluation of ESP collection efficiency. The results have shown that, using the DBD, we can effectively precipitate in Wire-to-Cylinder configuration as well as in Plate-to-Plate configuration (more than 99% of efficiency). The second step of the study was devoted to the characterization of the EHD flow phenomenon inside the investigated ESP, using Particle Image Velocimetry technique. The obtained results have established that the electric wind has a minimal effect on electrostatic precipitation. Outside the usual process of electric wind generation, the streamers seemed to be implicated in the precipitation process. This work is articulated around four chapters. In the first one, electrostatic precipitation is investigated as a pollution control device. The second underlines the electrical characterization of the ESP. In the third, the study of ESP performance in terms of precipitation is examined. Finally, the fourth is devoted to the characterization of the EHD flow phenomenon inside the investigated ESP
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Marques, André Gonçalo Ribeiro. "Um Bongo and sport: how can a brand communicate through its mascots." Master's thesis, NSBE - UNL, 2010. http://hdl.handle.net/10362/10331.
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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and EconomicsThe aim of this study is to analyze if young children (5 to 9 years old) are more aware and have more knowledge of brands that use mascots to communicate their products compared with brands that do not use mascots. Trade characters are useful to create awareness, and consumers that are able to establish empathy with a mascot will also have preference for the product with which the mascot is associated. The brand in which this study will be focused is Um Bongo. Also, this study will try to ensure that Um Bongo contains the essential components that every children need to practice Sport or any Physical Activity and that Um Bongo can create an incentive within its target to practice sport. Brand mascots also have the capability to be a symbol of the main attributes of a product and to communicate key product benefits of the product, like for example an association with sport. A specific type of Qualitative Research, Focus Group Analysis was performed with a sample of 30 children, with the objective of gathering information about the brand image of Um Bongo, awareness of brands and also the importance of sports in creating value for Um Bongo. The results suggest that the use of mascots provide more awareness for a brand, within young children. Moreover, the association with any sport or physical activity may also ensure an increase in the affective values for a given brand, although ethical concerns have to be used in the evaluation of using such claims, namely by checking if the product is nutritionally suitable to be consumed in sports occasions.
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Kee, Jennifer Michelle. "Characterisation of the temperate bacteriophages of Salmonella enterica and Salmonella bongori." Thesis, Connect to e-thesis to view abstract Move to record for print version, 2008. http://theses.gla.ac.uk/113/.
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Thesis (Ph.D.) - University of Glasgow, 2008.Ph.D. thesis submitted to the Department of Infection and Immunity, Faculty of Biomedical and Life Sciences, University of Glasgow, 2008. Includes bibliographical references. Print version also available.
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Katz, Sarah R. "Bonsai imperium : plant capitalism in the U.S. and Japan, 1853-1924." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/77641.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2012.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
CD-ROM contains copy of thesis in .pdf format.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (p. 133-139).
This thesis traces the formation of the international market for Japanese bonsai during the late 19th and early 20th centuries against the emergence of the United States and Japan as industrial, imperial nations and argues that bonsai represented an intermediary figure that supported a process of mutual imperial legitimation between the two countries. It examines the major mechanisms through which bonsai was created, marketed, and distributed-the commercial nursery, the catalog, the auction, and the exhibition-as well as American responses to bonsai. The formation of the bonsai market can be read within transnational consumer, aesthetic, and scientific discourses of cultural exchange. In the U.S., a split antiquarian and popular market for bonsai developed as part of the broader taste for Japanese goods as popularized at the World's Fairs of 1876, 1893, and 1904. In Japan, the newly established commercial nursery system and manufacturing and cultural policies of the new Meiji government, intended to establish Japan as a modern nation-state, supported the supply and formation of U.S. bonsai markets. To argue for bonsai's imbrication within a "botanic imperium," this thesis examines the relationship of bonsai to changing understandings of Japanese landscapes in both countries, and maps the relationship of the botany, geography, and agricultural science to shifts in horticultural practices and landscape aesthetics, as well as their literal and rhetorical deployment by Japan's Sapporo Agricultural College on Hokkaido Island and the U.S. Department of Agriculture's Bureau of Plant Industry. During this period, bonsai represented a global commodity that mediated and transformed a range of values (historical, cultural, political, and financial). Drawing upon Benedict Anderson's discussion of "print capitalism," this thesis suggests that bonsai can be understood as a form of "plant capitalism" that materialized the challenge, for the U.S., of how to at once appreciate yet contain Japan and, for Japan, of how to reconcile its isolated past with its ambitious intended commercial future. Allowing for bonsai's simultaneous existence as both an authentic expression of Japanese tradition and a mass-produced commodity, plant capitalism leveraged bonsai's multiple identities in support of U.S. and Japanese national and imperial discourse.
by Sarah R. Katz.
S.M.
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Gair, Jonathan Reavley. "Generalised Tolman-Bondi cosmologies and Kerr metric atoms." Thesis, University of Cambridge, 2002. https://www.repository.cam.ac.uk/handle/1810/251843.
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In the first part, we derive and investigate a family a cosmological models, which are a generalisation of the Lemaítre-Tolman-Bondi solution. The models are spherically symmetric and are composed of collisionless particles, with each particle possessing angular momentum about the symmetry centre. The radial motion and the magnitude of the angular momentum is the same for every particle on a given spherical shell, but there are particles moving in every tangential direction at each point. In this way the net angular momentum on a given spherical shell is zero and spherical symmetry is maintained. The solution to Einstein's equations describing the family of spacetimes with this matter content is derived in mass and proper time coordinates. The general properties of these models are discussed, including matching conditions and conditions to avoid shell crossing. The self-similar solutions in this family are derived and their physical properties described. A family of radiation spacetimes is obtained by taking the null limit of the particle solutions, i.e. by replacing the particles with photons. These generalize the Vaidya solution. Finally, by taking the limit in which every shell of particle has the same areal radius, a generalisation of the Kantowski-Sachs spacetime is found. These latter solutions may be envisaged as the surface of a cylinder, in which every circular cross section represents a two-sphere. The equation of relative motion of the matter shells along the surface of the cylinder is derived and discussed. The metrics in the general family represent inhomogeneous solutions with only a tangential pressure. This has application as a simple model cosmology or to describe the evolution of regions within our universe, for instance the recollapse of material to form a black hole within an expanding background. The spherical angular momentum model applies to many areas of astrophysics, including the modelling of clusters. These solutions provide a general relativistic description for such situations. The second part of the thesis concerns a problem on the much smaller, atomic scale. The Kerr-Newman solution in general relativity describes the spacetime around a charged and rotating black hole. If the limit G (r) 0 of this solution is taken, flat space is obtained, but the electromagnetic field remains. This electromagnetic field has many interesting properties, and possesses both a charge and magnetic moment. The G (r) 0 limit is appropriate for objects on an atomic scale. In oblate spheroidal coordinates, the Schrödinger equation separates for the electric part of the field, and the Klein-Gordon and Dirac equations separate for the full electromagnetic field. Of particular interest is the latter case, as it describes the interaction of two particles with magnetic moments.
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Bongs, Olivia [Verfasser]. "Paolo Bigelli : Biografie und ausgewählte Werke / Olivia Bongs." Paderborn : Universitätsbibliothek, 2019. http://d-nb.info/1194462189/34.
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Sanga, Daines. "Traditional Dances and Bongo Fleva: a Study of Youth Participation in Ngoma Groups in Tanzania." Universitätsbibliothek Leipzig, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-137461.
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Kasi ya vijana katika kukuza muziki wa kizazi kipya katika kipindi cha utandawazi haiendani na kasi ya ukuzaji wa ngoma za asili. Mpaka sasa haujafanyika utafiti wa kina kuhusu kuzuka kwa tabia hii. Makala haya yanatumia mahojiano na vikundi vya ngoma vitatu halikadhalika wanamuziki wa kizazi kipya kuweka bayana chanzo cha tatizo. Aidha, makala haya yanatumia nadharia ya utendaji kama darubini kuchunguza matatizo ya kijamii, kisiasa, kiuchumi na kiutamaduni yanayowakumba vijana na namna yanavyochochea mfumuko wa tabia hii mpya. Utafiti huu umegundua kwamba uhaba wa mianya ya kiuchumi na kisiasa kwa vijana, nafasi ya ngoma za asili katika jamii ya sasa, mahusiano hasi kati ya vijana na wazee katika kuuendeleza utamaduni pamoja na vijana kutaka maendeleo ya haraka kuwa ndio chimbuko la tatizo.
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Rodríguez, Oria Juan Carlos. "Sobre 'Bonsai' de Alejandro Zambra : narrativa en la medida de lo posible." Tesis, Universidad de Chile, 2013. http://www.repositorio.uchile.cl/handle/2250/116090.
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No autorizada su publicación a texto completo, según petición de su autorInforme de Seminario para optar al grado de Licenciado en Lengua y Literatura Hispánica mención Literatura
Esta inquietud nos ha llevado a analizar una de las novelas recientes de Alejandro Zambra, escritor chileno contemporáneo. En la medida que ha sido aclamado cuasi-transversalmente por la crítica, creemos que aportara su esclarecimiento microscópicopermitiría a su vez echar algunas luces sobre la fisonomía global del campo literario actual (¿qué valores literarios son los que se consagran? ¿qué definición de escritor? ). Nos parece una tarea importante, entendiendo los límites de la actividad artística/cultural, sobre todo a la luz del cambio de la situación político-social que se hace evidente hoy en Chile, ante un ascenso relativamente importante de la lucha de masas que comenzó a dar señas ya en 2006, tras casi dos décadas de paz social. Desde entonces, se han sucedido huelgas de trabajadores forestales y del cobre, trabajadores portuarios, luchas de pescadores artesanales, protestas populares tales como las de Magallanes, Aysén y Freirina, así como las mismas luchas estudiantiles.
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Bongsha, Bernard. "The impact of trade liberation on the manufacturing sector in Cameroon / B. Bongsha." Thesis, North-West University, 2011. http://hdl.handle.net/10394/6948.
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Trade liberalisation has been a prescription for all countries performing poorly and is
seen to be necessary in all economies that have grown (Krueger, 1997). Cameroon
initiated trade liberalisation in the late 1980s; however, the implementation was not
sustained because the government used tariffs to correct trade deficit and raise revenue.
By the early 1990s, the government was pressured by external factors, such as
participation in the World Trade Organisation (WTO), the imposition of a Structural
Adjustment Programme (SAP), membership of the Regional Trade Agreement (RTA),
the debt crisis, and internal factors, such as demands to promote competitiveness. The
tariff rates were reduced along with other quantitative restrictions.
The aim of this research is to measure the impact of trade liberalisation on the
manufacturing sector. The main hypothesis is that trade liberalisation based on theory
should have a positive impact on the manufacturing sector. To test this hypothesis,
appropriate methodologies were used to empirically determine the hypothesis.
Two periods were selected, 1980 to 1991 (pre–liberalisation period) and 1992 to 2006
(post–liberalisation period). The use of the period 1980 to 1991 allows for the capture of
the status quo ante policy, while the period 1992 to 2006 allows for the capture of postliberalisation
impacts (ex poste). The performance variables were regressed with trade
policy variables and other control variables that can influence performance. The
Ordinary Least Squares was used. The result of the study shows that reduction in
protection rates (tariff) did not affect manufacturing positively, as measured by the
export performance. The result from the estimation of the single equation supply model
reveals that the relative price variable proxied for by the exchange rate and imported inputs is an important determinant of the performance of the manufacturing sector, as
measured by export performance, though not significant statistically. The gravity model
is used to complement the results from the estimation of the single equation supply
model. The main manufacturing performance indicator is bilateral trade. Bilateral trade
was regressed with trade and other control variables such as the Gross Domestic Product
(GDP) of the two countries, distance, tariffs, membership of RTA, common language
and border and colonial ties, which can all have an impact on the performance of the
manufacturing sector. The results show that bilateral trade did not improve as a result of
liberalisation. The results further reveal that the membership in RTA and the reduction
in tariffs (all indications of liberalisation) did not positively influence bilateral trade in
manufacturing. The distance variable and GDP variables equally did not influence
bilateral trade in manufacturing.
Overall, support for the hypothesis that trade liberalisation in the early 1990s has had
positive impacts on the manufacturing sector in Cameroon has not been obtained. The
evidence indicates that liberalisation has negatively affected the manufacturing sector in
Cameroon. The findings show that the long–term relationship between trade opening and
industrialisation of the manufacturing sector is not stable and that trade opening
negatively affects the manufacturing sector of Cameroon. This result is explained by the
fact that importation of some inputs cannot be reduced. Moreover, Cameroon
manufacturing enterprises are apparently unable to satisfy domestic demand and are
uncompetitive. Given the evidence that, under Import Substitution Industrialisation
policy, Cameroon established manufacturing firms not on the basis of revealed or latent
comparative advantage, the seeming failure of ISI might be a consequence of these
wrong decisions that were based on political needs rather than sound economics (Bhagwati, 1978). It is recommended that Cameroon should develop an industrial
policy, which should be based on the identification of the revealed and latent
comparative advantage in addition to the progressive and systemic acquisition of
acquired comparative advantage as prescribe in the new trade theories. Government’s
role should be an enabling one relying on market determination of resource allocation,
and intervention should only take place when there is market failure. Clustering and
agglomeration should be encouraged using the suggested tools, which should avoid rent
seeking at all cost. Rigorous research at the microeconomic level is needed to identify
the comparative advantage of Cameroon. Despite the findings of the research, intuitive
reasoning and analysis of the various policies and actions indicate that trade
liberalisation and market–economic decision–making, through government’s support
(Lin & Monga, 2010) of the private sector (in a public–private partnership), through an
overarching vision, is the way to go.
The results from this research contribute towards policy–making that is grounded on
sound and rigorous research and not rhetorical or political exigencies, which will ensure
and guarantee a sound industrial policy reaffirming the importance of trade liberalisation
despite the criticism and an industrial policy based on revealed and latent comparative
advantages, which will lead to competitiveness with scientifically justified potentials for
the manufacturing sector (GESP, 2010:35).Thesis (Ph.D. (Economics))--North-West University, Potchefstroom Campus, 2012.
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Kelemen, Julia Carola [Verfasser]. "Untersuchungen an mutmaßlichen Virulenzfaktoren von Trueperella bonasi und Trueperella bialowiezensis / Julia Carola Kelemen." Berlin : Freie Universität Berlin, 2014. http://d-nb.info/104804744X/34.
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Penner, Andrew Jason. "Numerical analysis of the ultrarelativistic and magnetized Bondi--Hoyle problem." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/36734.
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In this thesis, we present numerical studies of models for the accretion of fluids and magnetofluids onto rotating black holes. Specifically, we study three main scenarios, two of which treat accretion of an unmagnetized perfect fluid characterized by an internal energy sufficiently large that the rest-mass energy of the fluid can be ignored. We call this the ultrarelativistic limit, and use it to investigate accretion flows which are either axisymmetric or restricted to a thin disk. For the third scenario, we adopt the equations of ideal magnetohydrodyamics and consider axisymmetric solutions. In all cases, the black hole is assumed to be moving with fixed velocity through a fluid which has constant pressure and density at large distances. Because all of the simulated flows are highly nonlinear and supersonic, we use modern computational techniques capable of accurately dealing with extreme solution features such as shocks.
In the axisymmetric ultrarelativistic case, we show that the accretion is described by steady-state solutions characterized by well-defined accretion rates which we compute, and are in reasonable agreement with previously reported results by Font and collaborators [1,2,3]. However, in contrast to this earlier work with moderate energy densities, where the computed solutions always had tail shocks, we find parameter settings for which the time-independent solutions contain bow shocks. For the ultrarelativistic thin-disk models, we find steady-state configurations with specific accretion rates and observe that the flows simultaneously develop both a tail shock and a bow shock. For the case of axisymmetric accretion using a magnetohydrodynamic perfect fluid, we align the magnetic field with the axis of symmetry. Preliminary results suggest that the resulting flows remain time-dependent at late times, although we cannot conclusively rule out the existence of steady-state solutions. Moreover, the flow morphology is different in the magnetic case: additional features are apparent that include an evacuated region near the symmetry axis and close to the black hole.
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Leithes, Alexander. "Perturbations in Lemaître-Tolman-Bondi and Assisted Coupled Quintessence cosmologies." Thesis, Queen Mary, University of London, 2017. http://qmro.qmul.ac.uk/xmlui/handle/123456789/24649.
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In this thesis we present research into linear perturbations in Lemaître-Tolman-Bondi (LTB) and Assisted Coupled Quintessence (ACQ) Cosmologies. First we give a brief overview of the standard model of cosmology. We then introduce Cosmological Perturbation Theory (CPT) at linear order for a at Friedmann-Robertson-Walker (FRW) cosmology. Next we study linear perturbations to a Lemaître-Tolman-Bondi (LTB) background spacetime. Studying the transformation behaviour of the perturbations under gauge transformations, we construct gauge invariant quantities in LTB. We show, using the perturbed energy conservation equation, that there is a conserved quantitiy in LTB which is conserved on all scales. We then briefly extend our discussion to the Lemaître spacetime, and construct gauge-invariant perturbations in this extension of LTB spacetime. We also study the behaviour of linear perturbations in assisted coupled quintessence models in a FRW background. We provide the full set of governing equations for this class of models, and solve the system numerically. The code written for this purpose is then used to evolve growth functions for various models and parameter values, and we compare these both to the standard CDM model and to current and future observational bounds. We also examine the applicability of the "small scale approximation", often used to calculate growth functions in quintessence models, in light of upcoming experiments such as SKA and Euclid. We nd the results of the full equations deviates from the approximation by more than the experimental uncertainty for these future surveys. The construction of the numerical code, Pyessence, written in Python to solve the system of background and perturbed evolution equations for assisted coupled quintessence, is also discussed.
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Firbas, Paul. "Apuntes sobre Don Quijote y las poéticas de la novela de Felix Martínez-Bonati." Pontificia Universidad Católica del Perú, 2013. http://repositorio.pucp.edu.pe/index/handle/123456789/101521.
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Olivo, Fabíola. "A educação como condição de acesso à cidadania / Fabíola Olivo ; orientação Lindomar Wessler Boneti." reponame:Biblioteca Digital de Teses e Dissertações da PUC_PR, 2008. http://www.biblioteca.pucpr.br/tede/tde_busca/arquivo.php?codArquivo=1173.
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Dissertação (mestrado) - Pontifícia Universidade Católica do Paraná, Curitiba, 2008Bibliografia: f. 101-107
Este estudo se situa no âmbito da linha de pesquisa História e Política da Educação, do Programa de Pós-graduação em Educação da PUCPR. A problemática da presente pesquisa concentra-se no seguinte questionamento: tendo-se em vista a complexidade sócio-pol
Abstract: This study is under the line of research History and Politics of Education, the Graduate Program in Education of PUCPR. The issue of this research focuses on the following question: taking into view the complex socio-political, economic and educ
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Boyeldieu, Pascal. "Identite tonale et filiation des langues sara-bongo-baguirmiennes (afrique centrale)." Paris 3, 1993. http://www.theses.fr/1993PA030129.
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Les langues sara-bongo-baguirmiennes (tchad, soudan, republique centrafricaine, zaire) revelent de fortes disparites tonales qui touchent a la fois l'identite des systemes (a deux, trois ou quatre registres distinctifs) et celle des schemes lexicaux (noms et verbes). En s'inspirant des principes du comparatisme historique on cherche 1) a restituer les caracteristiques essentielles d'un systeme tonal ancestral, commun a ces langus, 2) a expliquer les evolutions divergentes qui ont conduit a la diversite des systemes actuels et 3) a degager, sur l'indice d'innovations probables, un schema genealogique des langues de ce groupe. L'essai comparatif est complete par deux ouvrages descriptifs, de caractere monographique, consacres a des langues sara-bongobaguirmiennes (fer et yulu, bagiro) parlees en r. C. AThe sara-bongo-bagirmi languages (chad, sudan, centralafrican republic, zaire) display strong tonal dissimilarities which affect either the identity of systems (of two, three or four tones) or the identity of lexical patterns (nouns and verbs). Following the principles of historical comparatism this work attempts 1) to restitute the essential features of an ancestral tonal system, common to these languages, 2) to explain divergent evolutions which led to the variety of to-day systems and 3) to detect, by means of probable innovations, a genealogical diagram of the languages of this group. This comparative essay is completed by two descriptive works, of monographic nature, which are devoted to some of the sara-bongobagirmi languages (fer and yulu, bagiro) spoken in the c. A. R
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Bong, Maximilian [Verfasser]. "Das Dekarbonisierungspotenzial von Pensionskassenportfolios / Maximilian Bong." München : Verlag Dr. Hut, 2020. http://d-nb.info/1219477958/34.
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Hoogbergen, Wim. "The Boni Maroon wars in Suriname /." Leiden : New York ; København : Netherlands ; E.J. Brill, 1990. http://catalogue.bnf.fr/ark:/12148/cb35486514x.
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Ferrari, Angelo Giuseppe. "Fisica dell'accrescimento." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/10953/.
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Questo elaborato presenta una descrizione del fenomeno dell’accrescimento di materia su oggetti compatti, esponendo i principali modelli fisici a riguardo. Dopo un’introduzione, in cui viene mostrato come l’accrescimento rappresenti la più importante fonte di energia in astrofisica, si discute nel capitolo 1 il più semplice modello di accresci- mento, dovuto ad Hermann Bondi (1952). Tale modello, proprio per la sua semplicità, risulta molto importante, nonostante trascuri importanti aspetti fisici. Nel capitolo 2 si studia la fisica dei dischi di accrescimento, analizzando sia il caso generale che alcuni casi particolari, come quello stazionario o a viscosità costante. L’elaborato si conclude con una breve analisi dell’emissione termica da parte del disco di accrescimento.
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Begel, Andrew B. (Andrew Brian). "Bongo--a kids' programming environment for creating video games on the Web." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/43517.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1997.Includes bibliographical references (leaves 86-87).
by Andrew B. Bengel.
M.Eng.
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Fišl, Martin. "HISTORIE A VÝVOJ CHLAPECKÉHO SBORU BONI PUERI." Master's thesis, Akademie múzických umění v Praze. Hudební fakulta AMU. Knihovna, 2008. http://www.nusl.cz/ntk/nusl-78065.
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My thesis dissertate the theme of history and progress of the Czech Boys Choir Boni Pueri. The focal point of the thesis is in the interviews with conductors and pianists, who cooperated with Boni Pueri in the past or now. In interviews I analyze questions regarding conducting, choir school and especially piano accompaniment, which brings difficulties and specificity.
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Batistela, Airton Carlos. "Pedagogia da alternância : uma contraposição a teoria da modernização / Airton Carlos Batistela ; orientador, Lindomar Wessler Boneti." reponame:Biblioteca Digital de Teses e Dissertações da PUC_PR, 2011. http://www.biblioteca.pucpr.br/tede/tde_busca/arquivo.php?codArquivo=1883.
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Tese (doutorado) - Pontifícia Universidade Católica do Paraná, Curitiba, 2011Bibliografia: f. 226-244
Esta tese de doutorado se situa no âmbito das políticas educacionais brasileiras, cujo estudo se deu na Pedagogia da Alternância como modelo específico de educação do campo e as influências determinantes que as propostas de modernização estabeleceram sobr
This thesis falls within the framework of policies Brazilian educational, whose study took place in Pedagogy of Alternation as a specific model of rural education and the determinants that influence the established on proposals to modernize the way countr
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Olivo, Filho Pedro. "Políticas públicas de educação do campo : o caso MST / Pedro Olivo filho ; orientador, Lindomar Wessler Boneti." reponame:Biblioteca Digital de Teses e Dissertações da PUC_PR, 2009. http://www.biblioteca.pucpr.br/tede/tde_busca/arquivo.php?codArquivo=1655.
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Dissertação (mestrado) - Pontifícia Universidade Católica do Paraná, Curitiba,2009Bibliografia: f. 157-165
Este trabalho tem como objeto de estudo a configuração das políticas públicas de educação do campo: o caso do MST. Partindo desse tema, chegou-se à problemática de pesquisa que se concentra no seguinte questionamento: Como se configura a proposta política
This paper aims the study of country education policies configuration: MST case. Based on this theme, we got to the problematic research that focuses on the following questionable point: How does MST pedagogic policy proposal configure? We tried to verify
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Escobar, Tatiana Pires. "Políticas educacionais : mecanismos de inclusão social no sistema escolar / Tatiana Pires Escobar ; orientador, Lindomar Wessler Boneti." reponame:Biblioteca Digital de Teses e Dissertações da PUC_PR, 2010. http://www.biblioteca.pucpr.br/tede/tde_busca/arquivo.php?codArquivo=1738.
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Dissertação (mestrado) - Pontifícia Universidade Católica do Paraná, Curitiba, 2010Bibliografia: f. 116-119
O presente estudo, de natureza social e pedagógica, tem como objeto os mecanismos de inclusão e exclusão social no sistema escolar. Seu objetivo geral é investigar como se constituem os mecanismos de exclusão e inclusão, especificamente, no sistema escola
The object of this study of the social nature and education is the mechanisms of social inclusion and exclusion. The general objective of the study is to investigate the mechanism of exclusion and inclusion are constituted, specificially in the school sys
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CONCEIÇÃO, Dário César de Oliveira. "Estudo químico e atividade antifúngica das espécies Bauhinia cheilantha (Bong) Steudel e Bauhinia pentandra (Bong) Vog. Ex. Steua (Fabaceae)." Universidade Federal Rural de Pernambuco, 2015. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/7041.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The Bauhinia genus comprises about 300 species that are popularly known as "pata-de-vaca". Several species of Bauhinia presented activities such as antifungal, antitumor and hypoglycemic. The species studied in this work are Bauhinia cheilantha (Bong) Steud and Bauhinia pentandra (Bong) Vog. Ex. Steua (Fabaceae) that are also popularly known as "mororó-sem-espeinho" and "mororó-de-espinho" respectively. This study aimed to carry out the chemical and evaluate the antifungal activity of extracts and compounds obtained from the leaves and stems of these species. The Soxhlet extraction was conducted using the solvents hexane, ethyl acetate and methanol. Analysis of the chromatographic profiles was done by HPLC-DAD. For achieving antifungal activity of the fungal strains were used: yeast with the Candida guilhermondii LM 103 and dermatophytes Microsporum canis LM 910, M. gypseum LM 130 and Trichophyton rubrum LM 148 was determined and the minimum inhibitory concentration. Chromatographic fractionation column with Sephadex LH-20® resulted in the isolation of litospermosida substances kanferol, quercetin, and HPLC-DAD were isolated and quercitrin, afzelin for the species B. cheilantha. For the species B. pentandra fractionation resulted in kanferol substances, quercetin, pinitol cyclitol and flavonoids were identified 3-O-[β-D-glicopiranosil-(1→6)- α-L-ramnopiranosil]-7-O-α-L-ramnopiranosilkanferol, 3-O-[β-D-glicopiranosil-(1→6)-α-L-ramnopiranosil]-7-O-α-L- ramnopiranosil-3’-metoxiquercetina and 3-O-[β-D-glicopiranosil-(1→6)-α-L-ramnopiranosil]-7-O-α-L-ramnopiranosilquercetina. The Caule-Hex extracts, Folha -MeOH Folha-AcOEt and afzelin substances, litospermosida and querctitrina obtained from B. cheilantha and Caule-MeOH extracts and Folha-MeOH obtained from B. pentandra showed antifungal activity with minimum inhibitory concentrations between 512 ug / mL to 1024 / mL.
O gênero Bauhinia compreende cerca de 300 espécies que são popularmente conhecidas como “pata-de-vaca”. Várias espécies de Bauhinia apresentaram atividades como antifúngica, antitumoral e hipoglicemiante. As espécies estudadas neste trabalho são Bauhinia cheilantha (Bong) Steudel e Bauhinia pentandra (Bong) Vog. Ex. Steua (Fabaceae) que também são popularmente conhecidas como “mororó-sem-espinho” e “mororó-de-espinho” respectivamente. Este trabalho teve como objetivo realizar o estudo químico e avaliar a atividade antifúngica dos extratos e compostos obtidos das folhas e caules dessas espécies. A extração foi realizada em Soxhlet utilizando os solventes hexano, acetato de etila e metanol. A análise do perfil cromatográfico foi feita por CLAE-DAD. Para realização da atividade antifúngica foram utilizadas as cepas fúngicas: com a levedura Candida guilhermondii LM 103 e os dermatófitos Microsporum canis LM 910, M. gypseum LM 130 e Trichophyton rubrum LM 148 e foi determinada a concentração inibitória mínima. O fracionamento cromatográfico em coluna com Sephadex LH-20® resultou no isolamento das substâncias litospermosida, kanferol, quercetina, e por CLAE-DAD foram isoladas a quercitrina e afzelina para a espécie B. cheilantha. Para a espécie B. pentandra o fracionamento resultou nas substâncias kanferol, quercetina, ciclitol pinitol e foram identificados os flavonóides 3-O-[β-D-glicopiranosil-(1→6)- α-L-ramnopiranosil]-7-O-α-L-ramnopiranosilkanferol, 3-O-[β-D-glicopiranosil-(1→6)-α-L-ramnopiranosil]-7-O-α-L-ramnopiranosil-3’-metoxiquercetina 3-O-[β-D-glicopiranosil-(1→6)-α-L-ramnopiranosil]-7-O-α-L-ramnopiranosilquercetina. Os extratos Caule-Hex, Folha-MeOH, Folha-AcOEt e as substâncias afzelina, litospermosida e querctitrina obtidas de B. cheilantha e os extratos Caule-MeOH e Folha-MeOH obtida de B. pentandra apresentaram atividade antifúngica com concentrações inibitórias mínimas entre 512 μg/mL e 1024 μg/mL.
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Omari, Shani. "Call me ‘Top in Dar’ : the role of pseudonyms in Bongo Fleva music." Universitätsbibliothek Leipzig, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-90542.
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Over the last two decades Bongo Fleva music has become a popular form of entertainment as well as a key cultural element among Tanzanian urban youth. The objective of this paper is to examine the role of pseudonyms in this musical genre in Tanzania. It focuses on how Bongo Fleva artists adopt their pseudonyms and discusses their role in identity formation among urban youths in contemporary Tanzania. The paper argues that pseudonyms in Bongo Fleva, as in various other fields, have an important role to play in portraying one’s identity, culture, characteristics, profile, actions, hope and imagination.
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Omari, Shani. "Call me ‘Top in Dar’ : the role of pseudonyms in Bongo Fleva music." Swahili Forum 18 (2011), S. 69-86, 2011. https://ul.qucosa.de/id/qucosa%3A11465.
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Over the last two decades Bongo Fleva music has become a popular form of entertainment as well as a key cultural element among Tanzanian urban youth. The objective of this paper is to examine the role of pseudonyms in this musical genre in Tanzania. It focuses on how Bongo Fleva artists adopt their pseudonyms and discusses their role in identity formation among urban youths in contemporary Tanzania. The paper argues that pseudonyms in Bongo Fleva, as in various other fields, have an important role to play in portraying one’s identity, culture, characteristics, profile, actions, hope and imagination.
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Korol, Valeriya. "Accrescimento di Bondi con electron scattering per buchi neri al centro di galassie." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amslaurea.unibo.it/7727/.
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Il modello di Bondi rappresenta il modello di accrescimento più semplice, in quanto studia l'accrescimento su un BH isolato immerso in una distribuzione di gas infinita. In questa semplice trattazione puramente idrodinamica vengono trascurati molti aspetti importanti, come ad esempio il momento angolare, il campo magnetico, gli effetti relativistici, ecc. L'obiettivo di questa Tesi consiste nell'affinare tale modello aggiungendo alcune nuove componenti. In particolare, vogliamo studiare come queste nuove componenti possano influire sul tasso di accrescimento della materia.
Dopo una Introduzione (Capitolo 1), nel Capitolo 2 viene presentato il modello di Bondi originale, con lo scopo di ricostruire il procedimento matematico che porta alla soluzione e di verificare il funzionamento del codice numerico scritto per la soluzione dell'equazione di Bondi finale.
Tuttavia, il modello di accrescimento sferico stazionario tratta il potenziale gravitazionale di un oggetto puntiforme isolato, mentre in questo lavoro di Tesi si vogliono considerare i BH che si trovano al centro delle galassie. Pertanto, nel Capitolo 3 è stata rivisitata la trattazione matematica del problema di Bondi aggiungendo alle equazioni il potenziale gravitazionale prodotto da una galassia con profilo di densità descritto dal modello di Hernquist.
D'altronde, ci si aspetta che l'energia potenziale gravitazionale liberata nell'accrescimento, almeno parzialmente, venga convertita in radiazione. In regime otticamente sottile, nell'interazione tra la radiazione e la materia, domina l'electron scattering, il che permette di estendere in maniera rigorosa la trattazione matematica del problema di Bondi prendendo in considerazione gli effetti dovuti alla pressione di radiazione. Infatti, in un sistema a simmetria sferica la forza esercitata dalla pressione di radiazione segue l'andamento "1/r^2", il che comporta una riduzione della forza gravitazionale della stessa quantità per tutti i raggi. Tale argomento rappresenta l'oggetto di studio del Capitolo 4.
L'idea originale alla base di questo lavoro di Tesi, che consiste nell'unire i due modelli sopra descritti (ossia il modello di Bondi con la galassia e il modello di Bondi con feedback radiativo) in un unico modello, è stata sviluppata nel Capitolo 5. Utilizzando questo nuovo modello abbiamo cercato di determinare delle "ricette" per la stima del tasso di accrescimento, da utilizzare nell'analisi dei dati osservativi oppure da considerare nell'ambito delle simulazioni numeriche.
Infine, nel Capitolo 6 abbiamo valutato alcune applicazioni del modello sviluppato: come una possibile soluzione al problema di sottoluminosità dei SMBH al centro di alcune galassie dell'universo locale; per la stima della massa del SMBH imponendo la condizione di equilibrio idrostatico; un possibile impiego dei risultati nell'ambito dei modelli semi-analitici di coevoluzione di galassie e SMBH al centro di esse.
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Mostert, Andre. "Developing a systematic model for the capturing and use of African oral poetry: the Bongani Sitole experience." Thesis, Rhodes University, 2010. http://hdl.handle.net/10962/d1002154.
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Oral traditions and oral literature have long contributed to human communication. The advent of arguably the most important technology, the written word, altered human ability to create and develop. However, this development for all its potential and scope created one of the most insidious dichotomies. As the written word developed so too the oral word became devalued and pushed to the fringes of societal development. One of the unfortunate outcomes has been a focus on the nomenclatures associated with orality and oral tradition, which although of importance, has skewed where the focus could and should have been located, namely, how to support and maintain the oral word and its innate value to human society in the face of what has become rampant technological developments. It is now ironic that technology is creating a fecund environment for a rebirth of orality. The study aims to mobilize technauriture as a paradigm in order to further embed orality and oral traditions to coherently embrace this changing technological environment. The central tenet of the study is that in order to enhance the status of orality the innate value embodied in indigenous knowledge systems must be recognized. Using the work of Bongani Sitole, an oral poet, as a backdrop the study will demonstrate a basic model that can act as a foundation for the effective integration of orality into contemporary structures. This is based on work that I published in the Journal of African Contemporary Studies (2009). Given the obvious multi-disciplinary nature of the material the work covers a wide cross section of the debate, from questions of epistemology and knowledge in general in terms of oral traditions, through the consciousness and technical landscapes, via the experience with Sitole’s material to issues of copyright and ownership. This work has also been submitted for publication together with my supervisor as a co-author. The study intends to consolidate the technauriture debate and lay a solid foundation to support further study.
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Selby, Christopher. "Micropropagation of Sitka spruce : (Picea sitchensis (Bong.) Carr.)." Thesis, Queen's University Belfast, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356923.
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Suriano, Maria. "'Mimi ni msanii, kioo cha jamii' urban youth culture in Tanzania as seen through Bongo Fleva and Hip-Hop." Universitätsbibliothek Leipzig, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-91140.
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This article addresses the question how Bongo Fleva (or Flava, from the word ‘flavour’) - also defined as muziki wa kizazi kipya (‘music of a new generation’) - and Hip-Hop in Swa-hili, reflect Tanzanian urban youth culture, with its changing identities, life-styles, aspirations, constraints, and language. As far as young people residing in small centres and semi-rural ar-eas are concerned, I had the impression that they have the same aspirations as their urban counterparts, especially those in Dar es Salaam. They keep well up to date on urban practices through performances, radio and local tabloids, even if they lack the same job and leisure op-portunities as their city brothers. Although I do not take ‘youth’ as a fixed and homogeneous category, the ‘young generation’ has been assuming a central, though frequently ambiguous, position in many places in Africa (for this issue, see Burgess 2005). Here, however, I have chosen to focus on two urban contexts, namely Dar es Salaam and Mwanza, the sites of my one-and- -half-year fieldwork between 2004 and the end of 2005.
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Bongini, Mattia [Verfasser], Massimo [Akademischer Betreuer] [Gutachter] Fornasier, Benedetto [Gutachter] Piccoli, and Giuseppe [Gutachter] Buttazzo. "Sparse Optimal Control of Multiagent Systems / Mattia Bongini. Betreuer: Massimo Fornasier. Gutachter: Benedetto Piccoli ; Giuseppe Buttazzo ; Massimo Fornasier." München : Universitätsbibliothek der TU München, 2016. http://d-nb.info/1111038996/34.
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Luchmann, Julio Cesar. "Ensino superior no Brasil (1994-2006) : políticas de acesso e permanência / Julio Cesar Luchmann ; orientador, Lindomar Wessler Boneti." reponame:Biblioteca Digital de Teses e Dissertações da PUC_PR, 2007. http://www.biblioteca.pucpr.br/tede/tde_busca/arquivo.php?codArquivo=1050.
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Dissertação (mestrado) - Pontifícia Universidade Católica do Paraná, Curitiba, 2007Bibliografia: f. 72-77
Essa pesquisa estuda as políticas públicas de acesso e permanência ao ensino superior no Brasil. A educação tem um papel fundamental na formação e desenvolvimento de uma sociedade. No caso brasileiro verifica-se que a educação ainda não é tida como de fun
This research studies the public politics of access and permanence at the Brazil's Superior Education. There is a fundamental skill in the development and formation in one society, in the brazilian case, it is verified that in the education there is not a
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Reuster-Jahn, Uta. "Let`s go party!" Universitätsbibliothek Leipzig, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-91170.
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For over a decade now, Bongo Fleva has been the dominant category of popular music in Tanzania, surpassing Muziki wa Dansi (dance music) and Taarab in terms of its presence in the media. Bongo Fleva has become deversified in the last years and at present includes elements of traditional music as well as popular dance music, both of African and Western origin (Raab 2006: 43 ff.). As a result, contemporary Bongo Fleva is stylistically complex. Ther lyrics of Bongo Fleva are specifically determined by 1) the use of Swahili youth language and slang expressions. 2) the representation of modern and young lifestyles, and 3) socio-critical contens with pedagocial and moralistic tendencies. The lyrics of Bongo Fleva are marked by youth discourse which is most important for the construction of youth identities. While Bongo Fleva text with dialogic structure seem to continue the older tradition of Muziki wa Dansi, the dramatic texts remind of the way folk narratives are told in Tanzania. As the dramatic Bongo Fleva texts make use of direct speech, often of several characters, and without introduction, it seems that traditional techniques of story-telling have an effect on Bongo Fleva rap lyrics. In this article a rap text of this kind, Mikasi (\"Sex\"), released in 2004 by Bongo Fleva artist Ngwair, will be analysed with regard to its form, content and function. As it conteain different roles and dialogues, it is suitable for the investigation of youths`talk. A special focus will be put on the self-portrayal of the youths in the dialogues of the song, and on the question how boasting and dissing is performed in a dialogic text.
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Sartori, Simone. "Fisica dell'accrescimento." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/18765/.
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L’accrescimento è un fenomeno astrofisico di grande rilevanza, capace di liberare grandi energie in modo molto efficiente. Interviene negli AGN (nuclei galattici attivi formati da buchi neri supermassicci in accrescimento), regolando le grandi emissioni energetiche che li caratterizzano, e nei sistemi binari, dove oggetti compatti come stelle di neutroni e nane bianche vengono accresciuti dalle stelle compagne, liberando energia. Nell’Introduzione si analizzano gli aspetti energetici associati all’accrescimento degli AGN, dando una descrizone qualitativa dei fenomeni fisici associati. Successivamente, nel capitolo 2, viene ricavata la luminosità di Eddington, tetto massimo alla luminosità di un corpo in accrescimento sferico. Viene inoltre spiegato perché, in natura, questo limite non risulti invalicabile. Nel capitolo 3, servendosi anche dei risultati ottenuti nel capitolo precedente, si analizza il modello di Bondi per l’accrescimento sferico di un oggetto compatto immerso in una nube di gas infinita. Il modello è trattato inizialmente nel modo più semplice possibile, sotto ipotesi molto stringenti, mentre successivamente viene complicato con l’introduzione degli effetti dovuti all’elettron scattering. In conclusione, nel capitolo 4, si tratta l’accrescimento nei sistemi binari, permettendo di mettere in luce in modo più approfondito l’importante ruolo della viscosità.
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Kang, Bong-Gu [Verfasser]. "Modellierung von Textilbeton auf der Mikroskalenebene / Bong-Gu Kang." Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2011. http://d-nb.info/1018201270/34.
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Bambi, Aurora Cuaiela Joao Mateus. "Metalogenia de las carbonatitas en dominios plutónicos, subvolcánicos y volcánicos: Tchivira, Bonga y Catanda, Angola." Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/396375.
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Se han seleccionado tres carbonatitas de la estructura tectónica de Lucapa en Angola representativas de diferentes niveles de emplazamiento de los magmas: plutónico (Tchivira), subvolcánico (Bonga) y volcánico (Catanda).
Los objetivos del trabajo son los siguientes:
1) Establecer la secuencia de procesos que se dan en carbonatitas plutónicas, subvolcánicas y volcánicas;
2) establecer la distribución y el comportamiento de los elementos raros en cada uno de estos procesos.
La metodología incluye cartografía geológica de los afloramientos, muestreo según la misma o en algunos casos según columnas estratigráficas, estudio de las asociaciones minerales mediante microscopia óptica de luz transmitida/ reflejada, raman, microscopia electrónica cona analizador de energías de rayos X, difracción de polvo de rayos X, microsonda electrónica, análisis multielemental de elementos mayores y trazas y REE con ICP-MS, análisis microtermométrico de inclusiones fluidas, análisis de isótopos estables de
C y O en carbonatos.
Las carbonatitas se asocian con complejos alcalinos subsaturados de baja agpaicidad, aunque los elementos raros se concentran exclusivamente en las carbonatitas y, en menor medida, en aillikitas.
En las carbonatitas plutónicas e hipoabisales se registran tres estadios de cristalización principales, que controlan la cristalización y composición de los minerales de elementos raros:
a) estadio de cristalización magmático, con alta actividad de F en el magma y que produce la cristalización de
fluornatropirocloro; las tierras raras se concentran en fluorapatito y, en menor medida, en carbonatos primarios.
b) estadio de desgasificación y pérdida de álcalis que produce la fenitización del encajante, con precipitación de kenocalciopirocloro pobre en Na y en F. En el encaj ante pueden desarrollarse mineralizaciones similares.
c) estadio tardío, en que fluidos hidrotermales de origen meteórico procedentes de las rocas encajantes invaden la carbonatita. Se desestabilizan los carbonatos primarios, formándose ankeritización,dolomitización, fluoritización y silicificación de las carbonatitas primarias, a la vez que precipitan varias generaciones de pirocloro rico en Ba, Sr, Pb y Ta y, finalmente, rutilo rico en Nb. Las REE se concentran principalmente en carbonatos, principalmente en los del grupo de la synchisita, pero pueden estar en forma de silicatos de REE.
Por otra parte, durante los procesos supergénicos el pirocloro puede ser parcialmente desestabilizado y el niobio puede reconcentrarse en la estructura de minerales supergénicos de neoformación, como la goethita rica en Nb. Los elementos de las tierras raras pueden precipitar en forma de fosfatos secundarios de REE, como la rabdofana. En estas condiciones puede producirse la separación de Ce4+ del resto de REE. El contenido de F y Na del pirocloro primario disminuye proresivamente desde las carbonatitas plutónicas a las volcánicas, a la vez que el pirocloro se enriquece en Th, U y REE en la posición A y Ta y Zr en la posición B. En un mismo nivel estructural, las mayores concentraciones de pirocloro se dan donde se haya producido desvolatilización de la carbonatita. El
Nb, las REE y, en general, los elementos raros, tienen una muy alta movilidad en los fluidos carbonatíticos en condiciones hidrotermales, e incluso en las condiciones supergénicas.Three carbonatites from the Lucapa tectonic structure were selected for study, as representative of different levels of magma emplacement: plutonic (Tchivira), subvolcanic (Bonga) and volcanic (Catanda). The objectives of this research are the next two: 1) To establish the sequence of processes that occur in plutonic, subvolcanic and volcanic carbonatites. 2) To establish the distribution and the behavior of the rare elements in each of these processes. The methodology includes geological mapping of the outcrops, representative sampling following the above defined geological units (in some cases, along estratigraphic profiles), study of the mineral associations by transmitted/ reflected optical microscopy on thin/ polished section, Raman microprobe, scanning electron microscopy with energy dispersive analyses, X-ray powder diffraction, electron microprobe analyses, multielemental analyses of major and trace elements and REE with ICP-MS, microthermometry of fluid inclusions, C and 0 stable isotope analyses in carbonates. Carbonatites are associated with undersaturated alkaline complexes with low agpaicity, but the arre elements are concentrated ain the carbonatites and, in lesser extent, in aillikites. Three main stages of crystallization are found in the plutonic and hypabissal carbonatites. These stages control the crystallization and distribution of the minerals of rare elements: a) Stage of magmatic crystallization, whit a high F fugacity in the carbonatite magma; fluornatropyrochlore is extensively produced in this stage. Rare earth elements are concentrated in fluorapatite and, in lesser extension, in the primary carbonates. b) Stage of devolatilization and loss of alkalis. In this stage is produced the fenitization of host rocks, with precipitation of Na- and F-poor keno-calciopyrochlore. Similar enrichments can be found in the host rock. c) Late stage, when hydrothermal fluids of meteoric origin, invade the carbonatite coming from the host rocks. The primary carbonates become unstable, and the primary carbonatites are replaced by ankeritization,dolomitization, fluoritization and silicification processes, and new generations of Ba-, Sr-, Pb- and Ta-rich pyrochlore are produced, in many cases as replacements of the early formed pyrochlores. Finally, Nb-rich rutile is formed. REE are reconcentrated mainly in carbonates, commonly as members of the synchysite group, but REE silicates may also be formed. Moreover, pyrochlore may be unstable during the supergene processes and Nb may be reconcentrated in the structure of supergene minerals of neoformation, as Nb-rich goethite. The REE can precipitate as secondary phosphates, as rhabdophane. Ce4+ may fractionate from the other REE under these conditions. F and Na contents in the primary pyrochlore progressively decrease from the plutonic carbonatites towards the volcanic carbonatites. Conversely, an opposite trend is observed in the case of Th, U and REE in the A position, and in the case of Ta and Zr in the B position. The highest pyrochlore concentrations, for a given structural level, are found where carbonatite suffered a loss of volatiles. Nb, REE and, in general, the rare elements, have a very high mobility in the hydrothermal carbonatite fluids, and may also be mobile under supergene conditions.
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Amores, Casals Sandra. "Evolución metalogenética de complejos carbonatíticos en contexto hipoabisal y plutónico: Bonga y Monte Verde (Angola)." Doctoral thesis, Universitat de Barcelona, 2017. http://hdl.handle.net/10803/666643.
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En Angola afloran complejos carbonatíticos en todos los niveles de emplazamiento tanto plutónico, hipoabisal como volcánico. Recientemente, se han caracterizado en detalle algunos de estos complejos debido a las mineralizaciones en HFSE y REE que presentan así como su comportamiento en función del nivel de emplazamiento. Sin embargo, aún no se conoce con precisión la distribución de elementos raros en ambientes subvolcánicos explosivos. Los complejos de Monte Verde y Bonga muestran mineralizaciones en las manifestaciones explosivas de modo que su estudio ha permitido describir y comprender la distribución de elementos raros en tales condiciones. De forma paralela, los resultados obtenidos en esta tesis han permitido entender la relación entre carbonatitas y lamprófidos ultramáficos en el complejo de Bonga, asociación que hasta ahora ha sido descrita en escasos complejos.
El complejo de Bonga presenta cuerpos intrusivos mixtos de composición carbonatítica – lamprofíricos. Éstos fueron formados en estadios de cristalización tardíos por fenómenos de magma mingling como resultado de una intrusión de magma aillikítico y alnöítico dentro de una cámara magmática con magma carbonatítico residente. Esta mezcla de magmas dio lugar a estadios explosivos que no concentran especialmente elementos raros como HFSE y REE. De forma similar, las brechas subvolcánicas estudiadas en el complejo de Monte Verde contienen cantidades secundarias de estos elementos. En ambos complejos se concentran en cantidades traza de pirocloro empobrecido en F.
El estudio de la distribución de elementos raros y la evolución de la carbonatita de Bonga se ha realizado mediante la caracterización de la geoquímica del pirocloro. Se ha determinado pirocloro primario de Na y F en los diques anulares alrededor de la intrusión que indica una composición rica en álcalis en el magma carbonatítico. El contenido en Na y F disminuye debido a la progresión de la fenitización. Los estadios posteriores más tardíos que dan lugar a rocas de magnetita-apatito, al cuerpo calciocarbonatítico central y a la matriz carbonatítica, presentan pirocloro pobre en F con una proporción de Na inferior. Los mayores enriquecimientos de elementos raros HFSE y REE se registran en los pirocloros secundarios formados en procesos hidrotermales muy tardíos y que están asociados a la invasión de la carbonatita por fluidos procedentes de las rocas encajantes. En estos estadios es donde se concentran carbonatos y fosfatos de REE.
En consecuencia, el potencial metalogenético de las rocas de Bonga en ambientes explosivos no es destacable. Sin embargo, los elementos raros se suelen concentrar en estadios anteriores, en la formación de los diques anulares y rocas de magnetita – apatito.
El potencial en elementos raros en las brechas carbonatíticas subvolcánicas de Monte Verde es muy bajo. Tampoco las rocas plutónicas alcalinas asociadas contienen cantidades de elementos raros importantes, como indica la escasez en carbonatos, fosfatos de REE así como en silicatos y óxidos agpaíticos (loparita, eudialita y sorosilicatos de Na-Ti-Zr). Éstos además presentan intervalos de agpaicidad bajos.
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Sono, Sandisiwe. "Comparing estimates of zooplankton abundance from CUFES samples with those from a vertical bongo net." Master's thesis, University of Cape Town, 2008. http://hdl.handle.net/11427/6456.
Full textAbstract:
Includes bibliographical references (leaves 27-32).The accuracy of using CUFES (continuous underway fish egg sampler) as an alternative method to vertical bongo nets for sampling zooplankton abundance and distribution is assessed. Analysis is based on 14 taxonomic groups representing a wide variety of organism sizes. Samples were collected in March 2004 in the southern Benguela, South Africa. In total, 64 CUFES samples were collected while the ship was underway and 32 CUFES and vertical bongo net on-station samples were collected along four inshore-offshore transects. The frequencies of obtaining the taxa using the CUFES and vertical bongo net samples were the same for small copepods, amphipod adults and juveniles, and Nannocalanus.