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Análise econômica da produção e comercialização de dormentes ferroviários no Estado do Paraná (1981-6)Silva, Zenobio Abel Gouvêa Perelli da Gama e 27 June 2013 (has links)
Este trabalho identifica e analisa as principais características econômicas da produção e comercialização de dormentes no Estado do Paraná, mais especificamente na área sob a jurisdição da Superintendência Regional de Curitiba da Rede Ferroviária Federal S.A., SR-5, com seus 3.911,44 Km de malha viária, no período 1981-6. 0 dormente de madeira e o produto, ainda, com grande utilização nesta regional, tendo-se empregado, em caráter experimental, alguns quilômetros com peças de concreto. Quanto a formatação as peças de madeira apresentam-se com a configuração prismática, porém, para o futuro ë provável a aplicação de produtos roliços ou de duas faces. 0 suprimento de dormentes para esta regional apresentou, no período 1981-6, deficiências qualitativas e quantitativas devido à crescente escassez de florestas naturais no Estado do Paraná, assim como as peças produzidas são oriundas de espécies com poucas aptidões para esse processo produtivo, proporcionando um elevado índice de substituição destes produtos nas vias. As regiões de Guarapuava (PR) e União da Vitória (PR) apresentaram grande participação no suprimento de dormente para esta regional, onde se utilizam para o desdobro o sistema semimecanizado com moto-serra. Sob o aspecto da comercialização, tem-se para este mercado as características de um oligopólio na produção e um monopsónio no consumo. A produção e consumo apresentaram-se altamente concentrados, onde 2 entre 10 fornecedores, em 1986, representaram 82,1% da produção e a SR-5 alcançou 98% do consumo dessas peças. Os preços dos dormentes sofreram, no período analisado, uma perda real em seus valores, o que proporcionou aos produtores baixos índices de lucratividade. Em função dos dormentes de madeira apresentar maior economicidade de uso, tem-se como perspectiva futura para a SR-5, no curto-prazo, que o suprimento seja realizado por áreas onde existe abundância em florestas nativas, tais como o norte do Brasil, o Paraguai ou Argentina. Com relação ao longo-prazo, é viável a SR-5 tornar-se auto-suficiente mediante a implantação de povoamentos de eucalipto, os quais apresentam potenciais de rentabilidade ao redor de 7,15% ao ano.
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Tabelas de volume para Pinus taeda L. nos principais eixos de reflorestamento do Estado do ParanáUbialli, Jaime Antonio 11 June 2013 (has links)
A presente pesquisa versa sobre a construção de Tabelas de Volume Individual Total, com e sem casca para a espécie Pinus taeda Lineu, nos principais eixos de reflorestamento do Estado do Paraná. O eixo Palmas-Guarapuava abrange as micro-regiões homogêneas 23 e 24 e compreende os Municípios de Palmas, General Carneiro, Bituruna, Pinhão, Guarapuava, Inácio Martins e Laranjeiras do Sul e o eixo Telêmaco Borba-Sengés abrange as micro-regiões homogêneas 6 e 7, compreendendo os municípios de Sengés, Jaguariaíva, Arapoti, Pirai do Sul, Tibagi e Telêmaco Borba.
Foram testados cinco modelos volumétricos, para cada micro-região estudada, bem como para a massa de dados agrupados, gerando vinte e cinco equações volumétricas, sendo que a derivação das equações resultantes foi feita pelo método dos mínimos quadrados.
Entre as equações testadas aquela que forneceu, em todas as ocasiões, os melhores resultados foi a gerada pelo modelo volumétrico exponencial proposto por SCHUMACHER-HALL, (vide summarium) sendo que o Erro-Padrão Residual, o índice de Furnival e o Gráfico dos Resíduos foram os principais responsáveis pela eleição da melhor equação, seguidos pelo Coeficiente de Determinação e o F calculado.
Após desenvolvidas todas as equações de volume, realizou- se o teste de distribuição dos resíduos ao longo da linha de regressão através do Teste de Probabilidade Associada. Este teste demonstrou que em nove das equações testadas houve tendenciosidade na distribuição desses resíduos, sendo portanto, sumariamente excluídas. Realizou-se também, o Teste de Amplitude Múltipla de Tukey para diferentes números de repetições para as dezesseis equações remanescentes e constatou-se não haver diferença significativa, estatisticamente, entre as equações geradas ao nível de probabilidade de 0,01, o que torna válido o uso de qualquer equação dentro da área coberta por esta pesquisa.
Apresentou-se neste trabalho as cinco melhores equações volumétricas testadas para Pinus taeda, com casca, bem como as Tabelas de Volume Total com casca, geradas pelas mesmas.
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Characterization of Novel Thin-Films and Structures for Integrated Circuit and Photovoltaic ApplicationsJanuary 2017 (has links)
abstract: Thin films have been widely used in various applications. This research focuses on the characterization of novel thin films in the integrated circuits and photovoltaic techniques. The ion implanted layer in silicon can be treated as ion implanted thin film, which plays an essential role in the integrated circuits fabrication. Novel rapid annealing methods, i.e. microwave annealing and laser annealing, are conducted to activate ion dopants and repair the damages, and then are compared with the conventional rapid thermal annealing (RTA). In terms of As+ and P+ implanted Si, the electrical and structural characterization confirms that the microwave and laser annealing can achieve more efficient dopant activation and recrystallization than conventional RTA. The efficient dopant activation in microwave annealing is attributed to ion hopping under microwave field, while the liquid phase growth in laser annealing provides its efficient dopant activation. The characterization of dopants diffusion shows no visible diffusion after microwave annealing, some extent of end range of diffusion after RTA, and significant dopant diffusion after laser annealing.
For photovoltaic applications, an indium-free novel three-layer thin-film structure (transparent composited electrode (TCE)) is demonstrated as a promising transparent conductive electrode for solar cells. The characterization of TCE mainly focuses on its optical and electrical properties. Transfer matrix method for optical transmittance calculation is validated and proved to be a desirable method for predicting transmittance of TCE containing continuous metal layer, and can estimate the trend of transmittance as the layer thickness changes. TiO2/Ag/TiO2 (TAgT) electrode for organic solar cells (OSCs) is then designed using numerical simulation and shows much higher Haacke figure of merit than indium tin oxide (ITO). In addition, TAgT based OSC shows better performance than ITO based OSC when compatible hole transfer layer is employed. The electrical and structural characterization of hole transfer layers (HTLs) in OSCs reveals MoO3 is the compatible HTL for TAgT anode. In the end, the reactive ink printed Ag film for solar cell contact application is studied by characterizing its electromigration lifetime. A percolative model is proposed and validated for predicting the resistivity and lifetime of printed Ag thin films containing porous structure. / Dissertation/Thesis / Doctoral Dissertation Materials Science and Engineering 2017
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Ormosils fotoativos com fosfotungstato dopados com nanopartículas SiO2@TiO2 e NP de Ag: avaliação fotocrômica e potencial de inibição bactericida frente às bactérias Staphylococcus aureus e Pseudomona aeruginosa / Photoactive ormosil-phosphotungstate materials doped with SiO2@TiO2 and Ag nanoparticles: evaluation of their photochromic response and bacteriainhibition activity against Staphylococcus aureus and Pseudomonas aeruginosaLidiane Patricia Gonçalves 13 April 2015 (has links)
Neste trabalho foram preparados materiais híbridos do tipo silicatos organicamente modificados (Ormosils) contendo fosfotungstato, [PW12O40]-3 e dopados com nanopartículas sintetizadas core@shell SiO2@TiO2. Os objetivos a serem atingidos com estes materiais são obter filmes com alta sensibilidade à radiação UV e capazes de fotossintetizar nanopartículas de Ag no seu interior e superfície visando revestimentos antibacterianos. O pigmento fotocrômico nos filmes é o fosfotungstato e o core@shell irá atuar como agente potencializador da resposta fotocrômica dele. Dessa maneira variou-se a quantidade de volume da suspensão das partículas core@shell tentando maximizar a resposta fotocrômica com a menor quantidade possível de partículas adicionadas. Observa-se uma resposta não linear da sensibilidade ao UV observada pelo aumento no fotocromismo com a quantidade de suspensão de partículas adicionada. Ormosils com nanopartículas de Ag fotossintetizadas foram preparados com intuito de verificar a inibição desses na formação de biofilmes de bactérias patogênicas, ou seja, Staphylococcus aureus e Pseudomona aeruginosa. Os materiais foram caracterizados por espectroscopias vibracionais, espectroscopia de fotoelétrons de raios X (XPS), Difração de Raios X (DRX), Fluorescência de Raios X, Microscopia de Força Atômica(AFM) e Microscopia Eletrônica de Varredura (MEV). Nos testes de inibição da formação de biofilme notou-se uma maior inibição frente às bactérias S. aureus usando filmes de ormosils core@shell. Entretanto, para a inibição de P. aeruginosa a presença de core@shell não de maneira significativa. Na presença de NP de Ag ambas as bactérias foram inibidas totalmente. Os testes microbiológicos foram caracterizados através de contagem de placa, microscopia de Epifluorescencia, teste de reaproveitamento, teste do halo de crescimento, Microscopia Eletrônica de Varredura e espectroscopia de fotoelétrons de raios X (XPS). / In this project, hybrid materials based on organo modiefied silicates (Ormosils) containing phosphotunsgtic acid (HPW) and doped with SiO2@TiO2 core@shell nanoparticles were prepared. The objectives of the project was to obtain films of these hybrid ormosil-HPW-SiO2@TiO2 materials with high sensitivity to UV radiation and, which after coating with silver nanoparticles, could be used for antibacterial applications. The HPW in these films serves as the photochromic component while the role of SiO2@TiO2 particles was to enhance the innate phototromic reponse of the HPW. The prepared hybrid materials and hybrid films were characterized by vibrational spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction analysis, X-ray fluoresence, atomic force microscopy and scanning electron microscopy. The effect of addition of SiO2@TiO2 particles on the photochromic reponse was systematically studied in order to obtain films with maximum photochromic response. The UV sensitity or the photochromic response showed a non-linear increase as function of the amount of SiO2@TiO2 particles added. The hybrid ormosil-HPW-SiO2@TiO2 films modified with silver nanoparticles were studied for their antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa as model bacteria. The ormosil-HPW-SiO2@TiO2 films showed a good degree of inhibition against S. aureus, while the presence of SiO2@TiO2 in the ormosil-HPW films had no significant effect on the inhibition ability of the hybrid films against P. aeruginosa. The ormosil-HPW-SiO2@TiO2 films modified with Ag totally inhibited the growth of both the model bacteria studied. These photochromic and antibacterial hybrid films can find useful applications in UV-sensing devices and antibacterial coatings.
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Mapeando fundamentos do Constructo Neuromarketing com profissionais de empresa de publicidadeSoares Neto, Jo?o Batista 06 September 2007 (has links)
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Previous issue date: 2007-09-06 / This study aims to acknowledge the domain level and influence of the neuromarketing construct. This is done considering professionals at advertising agencies in Brazil. The
presence of concepts related to this new approach is very little divulged, and there are little analysis performed on this area. Thus, the research is of qualitative and exploratory nature and used as primary fonts books, articles related to marketing, neuroscience, and psychology as well as secondary fonts. A profound interview was realized aiming the main advertising agencies in Brazil. The public was composed by managers responsible for planning. A content analysis was performed afterwards. The advances related to the brain science have permitted the development of technological innovation. These go primarily towards knowledge and
unconscious experiences of consumers, which are responsible for the impulse of decision making and consumer behavior. These issues are related to Neuromarketing, that in turn, uses
techniques such as FMRI, PET and FDOT. These scan the consumer s brain and produces imagines on the neuron s structures and functioning. This is seen while activities such as mental tasks for the visualization of brands, images or products, watching videos and commercials are performed. It is observed that the agencies are constantly in search of new
technologies and are aware of the limitations of the current research instruments. On the other hand, they are not totally familiar with concepts related to neuromarketing. In relation to the neuroimage techniques it is pointed out by the research that there is full unawareness, but some agencies seem to visualize positive impacts with the use of these techniques for the evaluation of films and in ways that permit to know the consumer better. It is also seen that neuroimage is perceived as a technique amongst others, but its application is not real, there are some barriers in the market and in the agencies itself. These barriers as well as some
questioning allied to the scarce knowledge of neuromarketing, make it not possible to be put into practice in the advertising market. It is also observed that even though there is greater use of neuromarketing; there would not be any meaningful changes in functioning and structuring of these agencies. The use of the neuro-image machines should be done in research institutes and centers of big companies. Results show that the level of domain of the neuromarketing construct in the Brazilian advertising agencies is only a theoretical one. Little is known of this subject and the neurological studies and absolutely nothing of neuroimage techniques / O presente o estudo tem por objetivo conhecer o n?vel de dom?nio e influ?ncia do constructo neuromarketing junto a profissionais de ag?ncias publicidade no Brasil. Visto a
presen?a pouco difundida dos conceitos dessa nova abordagem, bem como a escassez de an?lises nessa ?rea, ? um estudo qualitativo e explorat?rio baseado em fontes prim?rias, atrav?s do levantamento de livros e artigos na ?rea de marketing, neuroci?ncia e psicologia, e fontes secund?rias. Foi realizada uma entrevista em profundidade nas principais ag?ncias de publicidade do Brasil, com os gerentes da ?rea de planejamento, e posterior an?lise de conte?do. Os avan?os na ci?ncia do c?rebro v?em permitindo desenvolvimentos tecnol?gicos inovadores voltados para o conhecimento de experi?ncias inconscientes dos consumidores, as quais s?o respons?veis por impulsionar as suas tomadas de decis?es e comportamentos de compra. Tais novidades relacionam-se ao Neuromarketing que, atrav?s das t?cnicas de neuroimagem, como a FMRI, a PET e o FDOT, escaneia o c?rebro dos consumidores produzindo figuras da estrutura ou do funcionamento dos neur?nios, enquanto eles se
envolvem em v?rias tarefas mentais como visualizar uma marca, imagem ou produto, ou assistir a v?deos e propagandas comerciais. Observou-se que mesmo cientes das limita??es
dos atuais instrumentos de pesquisa e da constante busca por novas tecnologias, as ag?ncias de publicidade n?o conhecem totalmente os conceitos relacionados ao neuromarketing. Com rela??o ?s t?cnicas de neuroimagem h? um un?nime desconhecimento, por?m, algumas ag?ncias visualizaram impactos positivos na utiliza??o dessas t?cnicas para avaliar filmes criados e no modo de entender o consumidor. Constatou-se que a neuroimagem seria mais
uma t?cnica dentre outras utilizadas, mas, sua aplica??o ainda n?o ? real, pois, existem algumas barreias no mercado e dentro das pr?prias ag?ncias. Essas barreiras, juntamente com
os questionamentos e o pouco conhecimento do assunto fazem com que a influ?ncia do neuromarketing n?o seja sentida de forma pr?tica no meio publicit?rio. Al?m disso, observouse, com o advento do neuromarketing, que n?o haveriam mudan?as estruturais e funcionais dentro das ag?ncias, pois, a operacionaliza??o dos aparelhos de neuroimagem dever?o acontecer nos institutos de pesquisa ou nos centros de pesquisas das grandes empresas. Os
resultados autorizam afirmar que o n?vel de dom?nio do constructo neuromarketing nas ag?ncias de publicidade brasileira ? apenas te?rico, pois, pouco se conhece a respeito dos estudos neurol?gicos e, absolutamente nada, das t?cnicas de neuroimagem
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Estrat?gia ambiental e ag?ncias de viagens e turismo :um estudo sobre a import?ncia de pr?ticas ambientais na escolha de um pacote tur?stico / Environmetal strategy and travel agencies: a study on the importance of environmental practices in the touristic packge purchaseC?mara, Michele Galdino 19 May 2006 (has links)
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Previous issue date: 2006-05-19 / The objective of the work was to investigate, from the vision of travel agents, the importance of environmental practices as a decision factor in the purchase of a tourist package. For in such a way, it was established as target population, the travel agencies and tourism linked to he Brazilian Association of Travel agencies ABAV, hearing the Brazilian travel agents that exerted the function in Natal, city in 2005. The election of the sample was accomplished using the simple random sampling technique. The amount of agents effectively searched was of 150 agents being distributed 150 questionnaires, with closed and opened questions, applied during the month of November in 2005. Results showed great variability of interviewed answers in that if it relates for sale of package tourist where the customer demonstrates enviromental concern with the environmental quality. Through multiple regression analyses, it was environmental concern with the environmental quality of the place and the perception of the practical importance of the existence environmental practices in the place as important factor in the decision of tourist package purchase / O objetivo do trabalho foi investigar, a partir da vis?o dos agentes de viagens, a import?ncia do emprego de pr?ticas ambientais como fator de decis?o de escolha de um pacote tur?stico. Para tanto foi estabelecida como popula??o alvo, as ag?ncias de viagens e turismo filiadas a Associa??o Brasileira de Ag?ncias de Viagens ABAV, tendo como amostra os agentes de viagens brasileiros que exerciam a fun??o na cidade de Natal em 2005. A sele??o da amostra foi efetivada utilizando-se a t?cnica de amostragem aleat?ria simples. A quantidade de agentes efetivamente pesquisados foi de 150 agentes sendo distribu?dos 150 question?rios, com perguntas fechadas e abertas, aplicados durante o m?s de novembro de 2005. Resultados mostraram grande variabilidade de respostas do entrevistado no que se refere ? venda de pacote tur?sticos onde o cliente demonstra a preocupa??o ambiental com a qualidade ambiental do local. Atrav?s de an?lises de regress?o m?ltipla, observou-se a exist?ncia de rela??o entre a venda de pacote tur?sticos onde o cliente demonstra a preocupa??o ambiental com a qualidade ambiental do local e a percep??o da import?ncia da exist?ncia de pr?ticas ambientais no local como fator importante na decis?o de compra de um pacote tur?stico
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Determinação da estrutura de uma série de tri(hidroximetil) amino metano complexados com íons metálicos (Cu, Ag, Ni, Zn) / X-ray crystal structures of Cu, Ag, Ni and Zn íons with tri(hidroximetil) amino methaneLenilda Austrilino Silva 05 December 1986 (has links)
As estruturas do tri(hidroximetil) amino metano complexado com cobre Cu(II), Cu[NH2C(COH3)3]2+H2O e do tri(hidroximetil)amino metano dopado com prata Ag(I), Ag[NH2C(COH3)3] foram determinados por difração de raios-x. O complexo contendo íons de cobre refinou até um R de 0.034 e foram encontradas as seguintes características principais: sistema cristalino monoclínico; grupo espacial C2/c, a=12.955(2)Å b=10.793(1)Å c=10.091(2)Å β=116.62° V=1261.3(6)޵ Z=4; xDc=1.694(2)g/cm-3; λ(KαMo)=0.71073Å das reflexões medidas 1441 tinham I> 3δ (I). O íon de cobre está coordenado por pares de átomos de oxigênio e nitrogênio os quais formam uma pirâmide de base quadrada, o oxigênio da molécula de água ocupa o outro vértice da pirâmide. A determinação dessa estrutura é utilizada na interpretação da formação de complexos de cobre com tri(hidroximetil) amino metano em função do pH. A estrutura do tri(hidroximetil) amino metano dopado com prata apresentou as seguintes características: sistema cristalino ortorrômbico; grupo espacial Pna21; a=7.800(2)Å b=8.810(3)Å c=8.850(2)Å V=608.85(4)޵ Dc=1.329g/cm-3; Dm=1.337g/cm-3; 435 reflexões com I> 3δ (I); R=0.13; o carbono central é coordenado tetraedricamente por três átomos de carbono do tri(hidroximetil) e um nitrogênio do grupo amino. As estruturas do tris dopado com níquel, e do tris dopado com zinco apresentam-se isomorfa com a estrutura do tris dopado com prata. / The crystal structures of the tri(hydroxymethyl) amine methane complexed with cooper Cu[NH2C(COH3)3]2+H2O and the silver Ag[NH2C(COH3)3] doped into the tri(hydroxymethyl) amine methane have been determined by x-ray diffraction. The complex involving Cu++ refined to final R-factor of 0.034, and the following main features were found: the crystal system is monoclinic and its space group is C2/c, a=12.955(2)Å b=10.793(1)Å c=10.091(2)Å β=116.62° V=1261.3(6)޵ Z=4; Dc=1.694(2)g/cm-3; λ(KαMo)=0.71073Å from measures done, 1441 had I> 3δ (I). The Cu++ is coordinated by couples of atoms of oxygen and nytrogen, which form a base of a quadrangular pyramid, the pyramid vertex is formed by the oxygen of the water molecule. The determination of this structure is used to interpret the rise of tri(hydroxymethyl) amine methane and complexed with Cooper varying the pH. The silver doped into the structures of tris(hydroxymethyl) amine methane presented the following features: crystal system is orthorrombic; space group is Pna21; a=7.800(2)Å b=8.810(3)Å c=8.850(2)Å V=608.85(4)޵ Dc=1.329 g/cm-3; Dm=1.337 g/cm-3; R=0.13; 435 reflections with I> 3δ (I) the central carbon is coordinated tetrahedrally by three atoms of carbon from tri(hydroxymethyl) and a nitrogen from the amine group.
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Electrochemical microsensor with in-situ fabricated Ag/AgCl reference electrode for high-pressure microfluidics / Elektrokemisk mikrosensor med referenselektrod av Ag/AgCl, tillverkad i mikrofluidikchip som tål höga tryckSödergren, Simon January 2017 (has links)
Electroanalysis offers cheap and selective analysis of interesting solutions. However, one of the most common drawbacks is the accessibility for electrochemical sensing. By using high-pressure microfluidics with an integrated three-electrode system, new possibilities open for increased accessibility. Therefore, there is a need to fabricate sustainable reference surfaces into highly pressure tolerant microchannels. In this thesis, Ag/AgCl reference surfaces were in-situ fabricated in high-pressure microfluidic chips. This was performed by electroplating Ag on thin film Pt in microchannels and then chlorinating the silver into Ag/AgCl. Electroanalysis of ferrocyanide was carried out in a microfluidic chip using one of the in-situ fabricated Ag/AgCl references. The half-wave potential showed to be around +251 mV and the electrochemical water window was measured to 1400 mV with a range between -300 mV and +1100 mV. The obtained values show to be comparable to reference data of similar experiments performed elsewhere. For some applications of electrochemistry, a catalysis surface is beneficial. Nanoporous Pt black has proved to generate high catalytic performance in electrochemistry. Therefore, attempts have been carried out to fabricate Pt black onto Pt thin films, with the vision to succeed with such fabrication within microfluidic channels. To summarize, this project work has showed a possibility to in-situ fabricate Ag/AgCl reference surfaces. The project has also showed how to use such surfaces as reference electrodes for electroanalysis in high-pressure microfluidic chips. Lastly, new challenges and ideas to fabricate catalysis surfaces on thin film electrodes in flow channels have been presented. By this thesis, one more step has been taken to increase the accessibility for electroanalysis.
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Intervention de la carnitine au cours du développement normal ou affecté chez Arabidopsis thaliana, en lien avec le métabolisme des lipides / Intervention of carnitine during normal and affected development of Arabidopsis thaliana, in connection with lipid metabolismNguyen, Phuong Jean 20 June 2014 (has links)
La modification des profils spécifiques en acides gras (AG) dans des huiles végétales peut servir à l’amélioration de leur qualité nutritionnelle, mais également à l’émergence d’une industrie biosourcée où les AG peuvent représenter une alternative aux ressources carbonées fossiles. Cependant des difficultés à modifier le profil en AG des huiles végétales, partagées par l’ensemble des équipes de recherche impliquées subsistent. Bien que la biosynthèse des AG est aujourd’hui bien caractérisée chez les plantes, des incertitudes persistent concernant les voies de transfert des AG du pool d’acyl-CoA vers les précurseurs lipidiques, et les formes de transport entre les différents compartiments impliqués dans les synthèses lipidiques. La carnitine est un acteur essentiel du trafic intracellulaire des AG chez l’animal et la levure. La présence avérée chez la plante d’acyl-Carnitines au côté de la carnitine libre, et la mise en évidence d’activités enzymatiques associées, prouvent également le lien entre la carnitine et le métabolisme des AG. Le travail de cette thèse a donc porté sur un approfondissement des connaissances sur le rôle de la carnitine dans le métabolisme lipidique chez Arabidopsis thaliana. A ce titre, nous avons pu montrer par LC-QQQ-MS/MS dans nos extraits végétaux, que l’oléoyl-, la palmitoyl- et la stéaroyl-Carnitine sont les espèces majoritaires et correspondent aux 3 AG (C18:1, C16:0 et C18:0) principalement synthétisés et exportés des plastes, pour alimenter la synthèse lipidique de la voie eucaryotique. De plus, une augmentation significative des teneurs en acyl-Carnitines a été mesurée dans des processus développementaux nécessitant une forte synthèse de glycérolipides, tels que le développement post-Germinatif (2 j post-Imbibition) ou lors de l’organogenèse racinaire, en concomitance avec le niveau d’expression des gènes marqueurs de la synthèse lipidique eucaryotique. D’autre part, la comparaison des teneurs en acyl-Carnitines et en carnitine estérifiée a révélée un résultat inédit montrant qu’une grande fraction de la carnitine est estérifiée à des AG inhabituels ou des acides organiques que nous cherchons actuellement à identifier par LC-QTOF-MS/MS. Ainsi, l’ensemble de nos résultats suggèrent que la carnitine pourrait être impliquée dans le trafic intracellulaire d’AG pour la synthèse de lipides eucaryotiques et de lipides particuliers et/ou dans la prise en charge d’acides organiques encore non identifiés dans les plantes. / Specific modification of fatty acid profiles (FA) in vegetable oils can help to improve their nutritional quality but also to the development of a bio-Based industry where FA may represent an alternative to fossil fuel sources. However problems to modify the FA profile of vegetable oils still remain and are shared by all the teams involved. Although the biosynthesis of AG is now well characterized in plants, uncertainties remain about the tranfert of AG of acyl-CoA pool to lipid precursors and the forms of transport between different compartments involved in lipid synthesis. Carnitine plays an essential role in intracellular trafficking of FA in animals and yeast. The known presence of acyl-Carnitines in plant alongside the free carnitine, and measurement of associatied-Enzymatic activities also show the link between FA metabolism and carnitine. During this thesis we tried to improve our understanding of the role of carnitine in lipid metabolism in Arabidopsis thaliana. We have shown by LC-QQQ-MS / MS in our plant extracts that oleoyl-, palmitoyl- and stearoyl-Carnitine are the predominant species and correspond to the three main AG (C18:1, C16:0 and C18:0) synthesized and exported from the plastids to supply the lipid synthesis of the eukaryotic pathway. Moreover, a significant increase of the levels of acyl-Carnitines were measured in developmental processes requiring high glycerolipid synthesis, such as the post-Germinative growth (2 days post-Imbibition) during root organogenesis, concomitantly with the level of expression of the eukaryotic lipid synthesis marker genes. Furthermore, comparison of the levels of acyl-Carnitine and carnitine ester revealed an unpublished results showing that a large fraction of carnitine is esterified to unusual FA or organic acids that we are currently identifing by LC QTOF-MS/MS. Thus, all of our results suggest that carnitine could be involved in the intracellular traffic of FA for the synthesis of lipids and particular eukaryotic lipids and/or in the transport of yet unidentified organic acids in plants.
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Interne Revision im internationalen Unternehmen und ihre Funktion / Internal Audit in International Companies and its FunctionFicalová, Markéta January 2009 (has links)
The main purpose of this paper is to establish an effective framework for a junior professional starting in the role of internal auditor in this corporation. The academic part of the paper lays out the auditing function in general, its scope, the related processes and the consulting function associated with it. The empirical part consists of an audit report based on real life data prepared for Trenkwalder International AG focussing on the findings and savings potential for a subsidiary Trenkwalder Kappa People a.s. in the Czech republic. The conclusions from this analysis underline the need for and the importance of implementing internal audit functions in corporations.
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