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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Using Thermal Energy Storage to Increase Photovoltaic Penetration at Arizona State University's Tempe Campus

January 2016 (has links)
abstract: This thesis examines using thermal energy storage as a demand side management tool for air-conditioning loads with the goal of increasing photovoltaic penetration. It uses Arizona State University (ASU) as a case study. The analysis is completed with a modeling approach using typical meteorological year (TMY) data, along with ASU’s historical load data. Sustainability, greenhouse gas emissions, carbon neutrality, and photovoltaic (PV) penetration are all considered along with potential economic impacts. By extrapolating the air-conditioning load profile from the existing data sets, it can be ensured that cooling demands can be met at all times under the new management method. Using this cooling demand data, it is possible to determine how much energy is required to meet these needs. Then, modeling the PV arrays, the thermal energy storage (TES), and the chillers, the maximum PV penetration in the future state can be determined. Using this approach, it has been determined that ASU can increase their solar PV resources by a factor of 3.460, which would amount to a PV penetration of approximately 48%. / Dissertation/Thesis / Masters Thesis Electrical Engineering 2016
62

Analise estrutural e funcional da lipoproteina de membrana externa omla de Xanthomonas citri / NMR resolution structure of the outer membrane lipoprotein omla from Xanthomonas citri

Vanini, Marina Marques Teixeira 18 February 2008 (has links)
Orientadores: Celso Eduardo Benedetti, Thelma Aguiar Pertinhez / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-10T11:25:32Z (GMT). No. of bitstreams: 1 Vanini_MarinaMarquesTeixeira_D.pdf: 4190459 bytes, checksum: 7f5524ada199418936817a26a2c2aadb (MD5) Previous issue date: 2008 / Resumo: Dentro do programa Smolbnet (Structural Molecular Biology Network) da Fapesp (Fundação de Amparo à Pesquisa do Estado de São Paulo), a orf (open reading frame) XAC1516 da bactéria causadora do cancro cítrico, Xanthomonas axonopodis pv. citri (Xac), foi selecionada para estudos de estrutura e função. XAC1516 codifica uma lipoproteína de membrana externa semelhante a membros da família OmlA/SmpA (Outer membrane lipoprotein A/Small membrane protein A) de pequenas lipoproteínas, amplamente distribuída entre as Proteobacteria 'beta¿ e 'gama¿. Apesar de se conhecer o papel de muitas lipoproteínas, nenhum membro OmlA/SmpA tem estrutura 3D (tridimensional) determinada e pouco se sabe sobre esta família do ponto de vista funcional, sendo sugerido um possível papel na manutenção da integridade do envelope celular. Curiosamente, no genoma de diversas bactérias o gene omlA apresenta localização adjacente ao gene fur (ferric uptake regulator), que codifica o principal regulador transcricional dos níveis intracelulares de ferro em bactérias Gram-negativas. O curto espaço intergênico entre omlA e fur sugere que os seus promotores são sobrepostos e que suas funções e/ou regulação podem estar associadas. Este trabalho procurou investigar a função da proteína OmlA de Xac, primordialmente através da determinação da sua estrutura 3D e análise das suas propriedades dinâmicas por Ressonância Magnética Nuclear (RMN). Também se buscou estudar a possibilidade de associação regulatória e/ou funcional entre omlA e fur, e o envolvimento do lócus no metabolismo de ferro ou na resposta ao estresse celular. Nós observamos que durante a infecção em folhas de citrus OmlA tem sua expressão aumentada em Xac e que neste processo os genes omlA e fur são co-ativados, sugerindo seu envolvimento na interação planta-patógeno. No entanto, o lócus não foi ativado em condições associadas ao metabolismo de ferro e à regulação por Fur observada em outros organismos. Ensaios de mono-híbrido foram realizados para tentar detectar possíveis fatores de ligação ao promotor do lócus omlA e fornecer informações sobre a sua regulação, mas sem sucesso. Pela primeira vez, as propriedades conformacionais e dinâmicas foram determinadas por RMN para um membro da família OmlA, e a estrutura 3D da proteína OmlA de Xac não revelou sua associação direta com processos de captação de ferro. A proteína possui extremidades desenvoveladas e uma porção central estruturada intercalada por loops flexíveis e composta de três fitas 'beta¿ e duas pequenas 'alfa¿ hélices que se empacotam num arquitetura do tipo bicamada 'alfa¿/¿beta¿. Curiosamente, este enovelamento se assemelha aos domínios da proteína BLIP (ß-lactamase inhibitory protein), um inibidor de 'beta¿-lactamase envolvido em interações proteína-proteína. Testes in vivo de co-expressão das proteínas OmlA e 'beta¿-lactamase não indicaram que OmlA possua atividade de inibição da 'beta¿-lactamase, e que portanto é provável que se associe a outra(s) proteína(s). Possíveis parceiros de interação não foram detectados através de experimentos de pull-down e coimunoprecipitação. Apesar disso, os resultados sugerem que a proteína OmlA pode estar envolvida em algum tipo de interação proteína-proteína associada à infecção na planta e sua co-ativação com fur deve fazer parte de uma resposta global relacionada à ativação de mecanismos de importância para sobrevivência de Xac durante a colonização na planta / Abstract: The XAC1516 gene from the citrus canker pathogen, Xanthomonas axonopodis pv. citri (Xac), was selected for structural and functional studies in the context of the Fapesp Smolbnet program. XAC1516 codes for an outer membrane lipoprotein similar to members of the OmlA/SmpA (Outer membrane lipoprotein A/Small membrane protein A) family of small lipoproteins widely distributed across the 'beta¿ and 'gama¿ Proteobacteria. Although the role of numerous bacterial lipoproteins is known, the tridimensional (3D) structure of OmlA/SmpA members has never been reported and little is known about its biological function. However, it has been proposed a role of OmlA in the stability of the cellular envelope. Curiously, the omlA gene is located adjacently to the fur (ferric uptake regulator) gene, which codes for the most important transcriptional regulator of iron intracellular levels in Gram-negative bacteria. The tight intergenic spacement between omlA and fur suggests that they have superimposed promoters and that their function or regulation may be associated. In this work, we have investigated the function of the OmlA protein from Xac essentially through its 3D structure determination and dynamic analysis by Nuclear Magnetic Resonance (NMR). We also investigated the possibility of a functional association between omlA and fur and the involvement of this locus in iron metabolism or cellular stress response. We found that in Xac OmlA expression is enhanced during citrus infection and that in this process omlA and fur are co-activated, thus suggesting their involvement in plantpathogen interaction. The locus, though, was not actived upon conditions associated to iron metabolism or Fur regulation already observed in other organisms. One-hybrid assay were performed in order to detect possible transcriptional factors implicated in omlA/fur expression or repression, but without success. Conformational and dynamical properties of OmlA were determined by NMR. The protein has unfolded N and C termini and a structurally well defined core interconnected by flexible loops and composed by three 'beta¿-strands and two small 'alfa¿-helices, which pack against each other forming a two-layer 'alfa¿/¿beta¿ scaffold. Curiously, this fold ressembles the domains of BLIP ('beta¿-lactamase inhibitory protein), a 'beta¿-lactamase inhibitor involved in protein-protein interaction. OmlA and 'beta¿-lactamase co-expression in vivo experiments did not indicate that OmlA has a 'beta¿-lactamase inhibitory activity. It is possible then that OmlA associates with another protein or proteins, but interacting partners were not detected through pulldown and coimmunoprecipitation assays. Nonetheless, the results suggests that OmlA may be implicated in some sort of protein-protein interaction associated to plant infection and its coactivation with fur may take part of a global response related to activation of important mechanisms for Xac surviving during its colonization in plant / Doutorado / Genetica de Microorganismos / Doutor em Genetica e Biologia Molecular
63

Análise de chaperonas hipotéticas da Xanthomonas axonopodis pv. citri por espectrometria de massas / Mass spectrometry analysis of secretion chaperones from Xanthomonas axonopodis pv. citri

Martins, Adriana Martini 17 August 2018 (has links)
Orientadores: Ljubica Tasic, Marco Aurelio Zezzi Arruda / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-17T19:46:42Z (GMT). No. of bitstreams: 1 Martins_AdrianaMartini_M.pdf: 8608342 bytes, checksum: fca9bf20d004eaa7ecfd1a0213382c0b (MD5) Previous issue date: 2010 / Resumo: A expressão protéica da bactéria Xanthomonas axonopodis pv. citri (Xac) foi avaliada aplicando técnicas de espectrometria de massas (MS) na tentativa de identificar a presença de 40 proteínas classificadas como possíveis chaperonas de secreção dos Sistemas Secretórios do Tipo III e IV. Embora o processo de virulência da Xac ainda não seja bem elucidado, acredita-se que as proteínas alvo desempenhem papel importante em caminhos secretórios. Estas proteínas participam no encaminhamento dos fatores de virulência para a secreção, proporcionando-lhes estrutura específica e compatível aos caminhos secretórios, previnem sua aglomeração e interações inapropriadas. Para alcançar os objetivos, a Xac foi cultivada em três condições distintas: meio de cultura LB, considerado como controle, e meios enriquecidos com extratos provenientes de folhas e cascas de laranja, que mimetizam a presença da planta hospedeira por conterem nutrientes específicos. A separação das proteínas da Xac foi realizada por eletroforese em uma e duas dimensões, que permitiu verificar a presença das proteínas alvo na região de 8-23 kDa com pI na faixa 4-7. Após lise tríptica, as análises de espectrometria de massas (MS) foram realizadas utilizando-se exclusivamente as técnicas de ionização suave MALDI (Matrix Assisted Laser Desorption/Ionization) e ESI (Electro Spray Ionization). Foram identificadas 12 proteínas da Xac até então consideradas hipotéticas, sendo uma delas, potencial chaperona secretória dessa bactéria. Aplicando técnica de cromatografia gasosa acoplada à espectrometria de massas (GC-MS) foi avaliado o consumo preferencial da Xac em relação aos extratos de casca e folha de laranja, como, também, a produção de metabólitos. O estudo de metalômica qualitativa possibilitou a identificação de espécies metálicas ligadas às proteínas da Xac por ICP-MS em frações obtidas por cromatografia líquida / Abstract: The proteome of the bacterium Xanthomonas axonopodis pv. citri (Xac) was studied with the aim to identify 40 hypothetical proteins and possible secretion chaperones from the Type III and Type IV Secretion Systems. It is believed that the target proteins can interact in a conserved manner with virulence factors providing them specific and appropriate structures to travel through the secretion pathways, prevent their improper interactions and agregation. For this purpose, Xac was cultived in three distinct conditions: rich medium (LB), used as the control condition, and in media enriched with orange¿s leaves and peels extracts, which simulate the presence of the host plant cell by containing specific nutrients. After protein separation by electrophoresis (1D and 2D), and detection of proteins in the region of 8-23 kDa and pI range from 4-7, characteristic of the target proteins, tryptic lysis was executed. Mass Spectrometry (MS) analyses applying soft ionization sources, MALDI (Matrix Assisted Laser Desorption/Ionization) or ESI (Electro Spray Ionization), enabled the identification of 12 proteins, one of them possible secretion chaperone, that were considered hypothetical. Gas chromatography coupled to mass spectrometry (GC-MS) was used as a tool for monitoring the consumption of specific nutrients present in the extracts by Xac and the production of its metabolites. Also, ICP-MS was applied in a qualitative Xac's metalomics that enabled the discrimination of important metallic species in protein fractions obtained by HPLC / Mestrado / Quimica Organica / Mestre em Química
64

Expressão diferencial de genes de laranja doce em resposta a infecção por Xanthomonas axonopodis pv. citri e axonopodis pv. aurantifolii / Gene expression analysis in sweet orange in response to Xanthomonas axonopodis pv. citri and Xanthomonas axonopodis pv. aurantifolii

Cernadas, Raul Andres 12 September 2008 (has links)
Orientador: Celso Eduardo Benedetti / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-14T23:20:27Z (GMT). No. of bitstreams: 1 Cernadas_RaulAndres_D.pdf: 2626366 bytes, checksum: 35442a2f5cdd8214cd7309ecd63c7954 (MD5) Previous issue date: 2008 / Resumo: A forma mais agressiva de cancro cítrico, cancrose A, é causada pela bactéria Xanthomonas axonopodis pv citri (Xac), que ataca qualquer variedade ou espécie de citros. Além de Xac, Xanthomonas axonopodis pv aurantifolii (Xaa) causa um tipo mais leve da doença, cancrose C, restrita ao limão Galego (Citrus aurantifolii). Na laranja Pêra (Citrus sinensis), Xaa provoca uma resposta de defesa que impede o desenvolvimento dos sintomas do cancro incluindo a ruptura da epiderme que é fundamental à disseminação da bactéria. Neste trabalho, abordamos a patogenicidade diferencial entre Xac e Xaa na laranja Pêra para estudar a expressão gênica na planta associada ao desenvolvimento dos sintomas (hipertrofia e hiperplasia celular) e à resposta de defesa. O projeto apresenta a identificação e caracterização de genes expressos diferencialmente em resposta à infecção por Xac e Xaa responsáveis pelo cancro cítrico. A partir de três estratégias independentes (Display diferencial de PCR, Hibridação subtrativa suprimida e micro arranjos de DNA) detalhou-se o perfil transcricional de folhas de laranja infiltradas com Xaa, Xac ou água como controle. Mais de 120 genes candidatos foram validados através de PCR quantitativo em tempo real ou hibridação Northern. Os genes diferencialmente expressos a 6 ou 48 hs após da infecção (hai) aparecem agrupados em categorias funcionais como: remodelamento de parede celular, divisão e expansão celular, tráfego de vesículas, resposta de defesa, metabolismo de nitrogênio e carbono e sinalização de hormônios como auxina, giberelina e etileno. Inicialmente, tanto Xaa quanto Xac induzem respostas de defesa associadas com ataque de patógenos incluindo a produção de espécies reativas de oxigênio e lignificação da parede celular. Notavelmente, a mudança no perfil transcricional mostra que Xac suprime as defesas da planta entre 6 e 48 hai, ao mesmo tempo em que induz genes relacionados com o metabolismo da parede celular, divisão celular e trafego de vesículas, entre outros. A conseqüência dessa manipulação transcricional no hospedeiro por parte de Xac dá origem à um estado fisiológico típico de expansão celular (hipertrofia). O inibidor de trafego de vesículas, Brefeldina A, atrasou o desenvolvimento dos sintomas do cancro, indicando que essa atividade está mais relacionada com hipertrofia celular do que com respostas de defesa. No perfil transcricional de folhas infectadas com Xaa destaca-se a ativação de uma via de sinalização por proteína quinase ativada por patógeno, envolvendo também fatores de transcrição do tipo WRKY, assim como elementos de resposta a etileno. Tanto Xac quanto Xaa parecem modular a transcrição de genes relacionados com sinalização e transporte de auxinas e biosíntese de giberelina. O tratamento de folhas de laranja com, ácido naftalenoacético (NAA) e ácido giberélico (GA3) demonstrou que esses hormônios induzem a expressão de genes de remodelamento de parede celular, biosíntese de giberelina e sinalização de auxina. Além disso, o inibidor de biosíntese de giberelina (Chlorocoline Chloride) diminuiu significativamente a expressão de genes induzidos por NAA sugerindo que exista uma regulação cruzada entre auxina e giberelina que controla a expressão de genes relacionados com divisão e expansão celular em citros. Finalmente, duas regiões promotoras de genes que codificam proteínas relacionadas com patogenicidade (PR-1 e PR-5) foram isoladas e caracterizadas. Esses genes são fortemente induzidos por Xaa e Xac em 6 e 48 hai. Substancialmente, existem elementos similares com o "upa box" nas regiões promotoras de PR-1 e PR-5. Mediante experimentos de Electrophoretic Mobility Shift Assays (EMSA) demonstrou-se que a proteína PthA4 de Xanthomonas é capaz de ligar-se no "upa box" presente nos promotores de PR-1 e PR-5. Tanto o promotor de PR-1 quanto o de PR-5 dirigem a expressão transitória do gene repórter uidA em N. benthamiana mediante Agro infiltração. / Resumo: A forma mais agressiva de cancro cítrico, cancrose A, é causada pela bactéria Xanthomonas axonopodis pv citri (Xac), que ataca qualquer variedade ou espécie de citros. Além de Xac, Xanthomonas axonopodis pv aurantifolii (Xaa) causa um tipo mais leve da doença, cancrose C, restrita ao limão Galego (Citrus aurantifolii). Na laranja Pêra (Citrus sinensis), Xaa provoca uma resposta de defesa que impede o desenvolvimento dos sintomas do cancro incluindo a ruptura da epiderme que é fundamental à disseminação da bactéria. Neste trabalho, abordamos a patogenicidade diferencial entre Xac e Xaa na laranja Pêra para estudar a expressão gênica na planta associada ao desenvolvimento dos sintomas (hipertrofia e hiperplasia celular) e à resposta de defesa. O projeto apresenta a identificação e caracterização de genes expressos diferencialmente em resposta à infecção por Xac e Xaa responsáveis pelo cancro cítrico. A partir de três estratégias independentes (Display diferencial de PCR, Hibridação subtrativa suprimida e micro arranjos de DNA) detalhou-se o perfil transcricional de folhas de laranja infiltradas com Xaa, Xac ou água como controle. Mais de 120 genes candidatos foram validados através de PCR quantitativo em tempo real ou hibridação Northern. Os genes diferencialmente expressos a 6 ou 48 hs após da infecção (hai) aparecem agrupados em categorias funcionais como: remodelamento de parede celular, divisão e expansão celular, tráfego de vesículas, resposta de defesa, metabolismo de nitrogênio e carbono e sinalização de hormônios como auxina, giberelina e etileno. Inicialmente, tanto Xaa quanto Xac induzem respostas de defesa associadas com ataque de patógenos incluindo a produção de espécies reativas de oxigênio e lignificação da parede celular. Notavelmente, a mudança no perfil transcricional mostra que Xac suprime as defesas da planta entre 6 e 48 hai, ao mesmo tempo em que induz genes relacionados com o metabolismo da parede celular, divisão celular e trafego de vesículas, entre outros. A conseqüência dessa manipulação transcricional no hospedeiro por parte de Xac dá origem à um estado fisiológico típico de^expansão celular (hipertrofia). O inibidor de trafego de vesículas, Brefeldina A, atrasou o desenvolvimento dos sintomas do cancro, indicando que essa atividade está mais relacionada com hipertrofia celular do que com respostas de defesa.No perfil transcricional de folhas infectadas com Xaa destaca-se a ativação de uma via de sinalização por proteína quinase ativada por patógeno, envolvendo também fatores de transcrição do tipo WRKY, assim como elementos de resposta a etileno. Tanto Xac quanto Xaa parecem modular a transcrição de genes relacionados com sinalização e transporte de auxinas e biosíntese de giberelina. O tratamento de folhas de laranja com, ácido naftalenoacético (NAA) e ácido giberélico (GA3) demonstrou que esses hormônios induzem a expressão de genes de remodelamento de parede celular, biosíntese de giberelina e sinalização de auxína. Além disso, o inibidor de biosíntese de giberelina (Chlorocoline Chloridè) diminuiu significativamente a expressão de genes induzidos por NAA sugerindo que exista uma regulação cruzada entre auxina e giberelina que controla a expressão de genes relacionados com divisão e expansão celular em citros. Finalmente, duas regiões promotoras de genes que codificam proteínas relacionadas com patogenicidade (PR-1 e PR-5) foram isoladas e caracterizadas. Esses genes são fortemente induzidos por Xaa e Xac em 6 e 48 hai. Substancialmente, existem elementos similares com o "upa box" nas regiões promotoras de PR-1 e PR-5. Mediante experimentos de Electrophoretic Mobility Shift Assays (EMSA) demonstrou-se que a proteína PthA4 de Xanthomonas é capaz de ligar-se no "upa box" presente nos promotores de PR-1 e PR-5. Tanto o promotor de PR-1 quanto o de PR-5 dirigem a expressão transitória do gene repórter uidA em N. benthamiana mediante Agro infiltração / Abstract: The most aggressive form of the citrus canker disease is caused by the bacteria Xanthomonas axonopodis pv. citri (Xac), which can infect all commercial varieties or species of citrus. In addition to Xac, Xanthomonas axonopodis pv. aurantifolii (Xaa) causes a weaker form of the disease, known as cancrose C, which is restricted to Mexican Lime (Citrus aurantifolii). In sweet orange (Citrus sinensis), Xaa triggers a defense response that halts the canker-symptoms development including the epidermal rupture, which is essential for bacterial dissemination. In this work, we approached the differential pathogenicity existing between Xac and Xaa in order to survey the host gene expression associated with symptoms development (cellular hypertrophy and hyperplasia) and defense response in sweet orange. The project presents the identification and initial characterization of differentially expressed genes in response to the infection with the citrus canker pathogens, Xac and Xaa. Three independent strategies were conducted in order to have a detailed transcriptional profiling of orange leaves infected with Xaa, Xac or water as mock control (Differential Display PCR, Suppression Subtractive Hybridization and GeneChip Microarrays). More than 120 candidate genes were validated through quantitative real time PCR or Northern blot. The differentially expressed genes at 6 or 48 hours after infection (hai) were grouped into functional categories: cell-wall remodeling, cell division and expansion, vesicle trafficking, carbon and nitrogen metabolism or hormone signaling, auxin, gibberellin and ethylene. Initially, both Xaa and Xac elicit a defense response associated with pathogen attack that includes the production of reactive oxygen species (ROS) and cell-wall lignification. Notably, the changes in the transcriptional profiles show that Xac suppresses the plant defenses between 6 and 48 hai and at the same time it induces genes related to the cell-wall metabolism, cell division and vesicle trafficking among others. The consequence of this host manipulation by Xac originates a physiological state very similar to that of cell expansion (hypertrophy). The vesicle trafficking inhibitor, Brefeldin A, delayed the development of canker symptoms indicating that this activity is more related to the cellular enlargement than to the defense responses. The transcriptional profile of Xaa-infiltrated leaves highlights the activation of amitogen-activated protein kinase (MAPK) signaling pathway related to pathogen attack with the involvement of other components of defense responses like WRKY-transcriptional factors and ethylene-response elements. Both Xac and Xaa appear to modulate the transcription of genes related to auxin signaling and transport and gibberellin biosynthesis. Treatments of orange leaves with 1- naphthylphthalamic acid (NAA) . / Abstract: The most aggressive form of the citrus canker disease is caused by the bacteria Xanthomonas axonopodis pv. citri (Xac), which can infect all commercial varieties or species of citrus. In addition to Xac,Xanlhomonas axonopodis pv. aurantifolii (Xaa) causes a weaker form of the disease, known as cancrose C, which is restricted to Mexican Lime {Citrus aurantifolii). In sweet orange {Citrus sinensis), Xaa triggers a defense response that halts the canker-symptoms development including the epidermal rupture, which is essential for bacterial dissemination. In this work, we approached the differential pathogenicity existing between Xac and Xaa in order to survey the host gene expression associated with symptoms development (cellular hypertrophy and hyperplasia) and defense response in sweet orange. The project presents the identification and initial characterization of differentially expressed genes in response to the infection with the citrus canker pathogens, Xac and Xaa. Three independent strategies were conducted in order to have a detailed transcriptional profiling of orange leaves infected with Xaa, Xac or water as mock control (Differential Display PCR, Suppression Subtractive Hybridization and GeneChip Microarrays). More than 120 candidate genes were validated through quantitative real time PCR or Northern blot. The differentially expressed genes at 6 or 48 hours after infection (hai) were grouped into functional categories: cell-wall remodeling, cell division and expansion, vesicle trafficking, carbon and nitrogen metabolism or hormone signaling, auxin, gibberellin and ethylene. Initially, both Xaa and Xac elicit a defense response associated with pathogen attack that includes the production of reactive oxygen species (ROS) and cell-wall lignification. T Notably, the changes in the transcriptional profiles show that Xac suppresses the plant defenses between 6 and 48 hai and at the same time it induces genes related to the cell-wall metabolism, cell division and vesicle trafficking among others. The consequence of this host manipulation by Xac originates a physiological state very similar to that of cell expansion (hypertrophy). The vesicle trafficking inhibitor, Brefeldin A, delayed the development of canker symptoms indicating that this activity is more related to the cellular enlargement than to the defense responses. The transcriptional profile of Xaa-infiltrated leaves highlights the activation of a mitogen-activated protein kinase (MAPK) signaling pathway related to pathogen attack with the involvement of other components of defense responses like WRKY-transcriptional factors and ethylene-response elements. Both Xac and Xaa appear to modulate the transcription of genes related to auxin signaling and transport and gibberellin biosynthesis. Treatments of orange leaves with 1-naphthylphihalamic acid (NAA) e Gihherellic Acid (GKi) demonstrated that these hormones induce the expression of genes related to cell-wall remodeling, gibberellin biosynthesis and auxin signaling. Moreover, the gibberellin-biosynthesis inhibitor (Chlorocoline Chloride) decreased significantly the expression of auxin-induced genes suggesting a cross-talk regulation between auxin and gibberellin controlling the expression of citrus genes associated with cell division and expansion. Finally, two promoter regions of the pathogenesis related (PR) genes, PR-I and PR-5.2, were isolated and characterized. These genes are strongly up-regulated by Xaa and Xac at 6 or 48 hai. Substantially, there are "upd" box-like motifs in the promoter regions of both PR-I and PR-5.2. By means of Electrophoretic Mobility Shift Assays (EMSA) we have demonstrated that PthA4 from Xac is capable of binding the "upd" box-like regions found in PR-1 e PR-5 promoters. Furthermore, both of the isolated promoters (PR-1 and PR-5) address the transient expression of the reporter gene uidA in JV. bethamiana leaves through agro infiltration / Doutorado / Genetica Vegetal e Melhoramento / Doutor em Genetica e Biologia Molecular
65

Energy Yield Simulation Analysis of Bifacial PV Installations in the Nordic Climate

Graefenhain, Marcus January 2017 (has links)
Recently, commercial softwares for PV system simulation released bifacial extensions. While research laboratories have developed their own simulation tools, in both cases it is imperative to display their applicability, as well as continuously assess their accuracy and/or limitations in practice, i.e. for different bifacial PV systems and field conditions. This paper presents a design and energy yield simulation study of two bifacial PV systems installed and operating in Nordic climate conditions, i.e. in Vestby, Norway ( System 1) and in Halmstad, Sweden (System 2). The aim of this study is: • To validate and compare the accuracy of two bifacial PV simulation tools newly featured in the software platforms of PVsyst and Polysun respectively, against real-field energy yield data. Each investigated system is modeled and analyzed with both simulation tools, resulting in four individual case stu dies. Further details on the systems’ monitoring set-up, the data input, modeling steps, and the involved uncertainties are presented in this paper. The results of the four case studies show higher percent deviations (both monthly and hourly data) between simulated energy results and real energy results during winter periods compared to summer periods. System 1 had a lower bifacial gain (around 2%) than System 2 which ranges from 2% in summer periods to 25% during winter. The collected field data had too high of an uncertainty to determine whether the bifacial PV simulation extensions are accurate within a certain tolerance. The reason for higher simulation inaccuracy in the winter is due to: lower production, higher uncertainty in albedo, and more diffuse irradiation. It is recommended for the bifacial PV simulation extensions include options for considering a variable albedo. The bifacial gain in System 2 was higher in the winter because of the higher albedo value given whereas in System 1, the albedo value was kept constant. Further parametric studies should be conducted on the bifacial gain using vertical mounted bifacial PV modules oriented east and west for Nordic climate conditions.
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Couplage onduleurs photovoltaïques et réseau, aspects contrôle / commande et rejet de perturbations / Grid connected PV systems, control / command aspects and disturbances decoupling

Le, Thi Minh Chau 25 January 2012 (has links)
Cette thèse concerne le couplage des systèmes photovoltaïques (PV) au réseau de distribution du point de vue contrôle/commande et rejet de perturbation. Le raccordement au réseau induit des couplages aux effets parfois indésirables. Le problème majeur est dû aux creux de tension provoqué par des court-circuits, à la foudre ou encore à certaines manœuvres. Dans ce contexte, des déconnexions apparaissent et parfois sont non-jutifiées, tout particulièrement en cas de défaut sur un départ adjacent BT/HTA; en cas d'un fort taux de pénétration de systèmes PV, une telle déconnexion qui serait généralisée peut avoir des conséquences néfastes. Les travaux de cette thèse se sont focalisés sur ce problème de couplage : effet des systèmes PV sur le réseau et réaction des systèmes PV face aux perturbations du réseau. A cet effet, des adaptations aux protections découplage sont proposées pour une intégration harmonieuse du système PV. Des stratégies de gestion de l'énergie ont été également mises au point participation à l'amélioration de la qualité de l'énergie localement et pour la tenue des systèmes PV aux perturbations. / This thesis concerns the coupling of photovoltaic (PV) to the distribution network in terms of control/command and disturbance decoupling. The connection of PV system to the grid induces the coupling some unwanted effects. The major problem is due to voltage sags caused by short circuits, lightning or some operations. In this context, disconnections occur and sometimes are unjustifies, especially in case of fault on LV/MV adjacent feeder and in case of a high penetration of PV systems, a such disconnection can provoke adverse consequences. The work of this thesis focused on the problem of coupling: effect of PV systems on the network and reaction of PV system facing network disturbance. For this purpose, adaptations to the decoupling protections are proposed for harmonious integration of PV. Strategies for energy management were also developed participation in improving the quality of local energy and for the holding of PV systems to disturbances.
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Public policies for the development of solar photovoltaic energy and the impacts on dynamics of technology systems and markets / Les politiques de développement du solaire photovoltaïque et leurs impacts sur les dynamiques des technologies et des marchés

Yu, Hyun Jin Julie 22 June 2016 (has links)
Le marché des systèmes photovoltaïques a connu une forte croissance cette dernière décennie soutenue par des actions politiques favorables dans un contexte de transition énergétique. Pourtant, malgré ces conditions bénéfiques, le marché mondial du PV a paradoxalement traversé une période chaotique rencontrant des problèmes de surproduction, une crise industrielle et des différends commerciaux durable entre pays. Cette thèse part de ces problématiques et tente de comprendre les politiques publiques PV et les impacts sur la dynamique des technologies et des marchés. Afin de préciser ces questions, une approche systémique est utilisée pour fournir une compréhension correcte des mécanismes généraux des politiques publiques PV. Une vue d’ensemble systémique concrète de ces mécanismes est construite sur la base d’analyses théoriques et historiques en définissant les variables clés et le contexte. Une analyse rétrospective utilisant des mappings construits pour l’occasion est conduite afin de cerner les limites et défis critiques du secteur PV ainsi que les facteurs de risque. Cette thèse montre également la façon dont la nature du contexte politique change en liaison avec la dynamique du secteur PV. La thèse met en évidence que la dynamique nationale a été brisée par l’entrée de la Chine sur le secteur PV. La thèse propose au final des orientations stratégiques pour le développement du PV selon deux dimensions, nationale et internationale. Au niveau national, la thèse s’intéresse à l’autoconsommation PV en tant que manière naturelle d’utiliser l’énergie PV dans le système électrique. Cette analyse implique un changement de nature des politiques PV dans le futur. Pour terminer, afin de résoudre la crise industrielle actuelle, la thèse présente des possibilités d’actions internationales en collaboration pour créer une nouvelle demande PV dans le contexte international en recherchant des bénéfices économiques et environnementaux au niveau mondial. / Solar PV systems have experienced strong market growth over the last decade supported by favorable political reactions in the energy transition context. However, despite these favorable conditions, paradoxically, the global PV market recently went through a chaotic time encountering the overproduction issue, the industry crisis and the long-lasting trade disputes. This thesis started from these problematics to understand the PV public policies and the impacts on dynamics of technology systems and markets. In order to define those issues, a systemic approach is taken to provide an accurate comprehension of the overall mechanisms of PV public policies. The concrete systemic vision of PV policy mechanisms is constructed based on theoretical and historical analysis by defining key variables and the context. A retrospective analysis using the proposed mapping tools is conducted to understand critical limits and challenges of PV development and to identify risks factors in the sector. This thesis also demonstrates how the nature of policy context changes in combined with the dynamic feature of the PV sector. Our analysis highlights the nationwide PV policy dynamics was broken with the arrival of China in the PV sector. This thesis eventually proposes strategic orientations of PV development at the two dimensions from both national and international perspectives. At the national level, this thesis discusses on PV self-consumption as the natural way of PV power use in the electricity system. This analysis implies a change in the nature of PV policies in the future. Next, as a response to the current global industry crisis, the thesis proposes opportunities of international collaborative actions to create new PV demand in the international context in pursuit of global economic and environmental benefits.
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Solcellsanläggningar : Optimering och lönsamhet / Photovoltaic systems : Optimization and profitability

Landenstad, Henrik, Rokka, Martin January 2020 (has links)
Rapporten har utförts i samarbete med Vinnergi som är ett konsultbolag inom både el-, fiber- och mobilnät. Syftet är att undersöka hur elnätet påverkas av det ökade antalet solcellsanläggningar samt försöka svara på vad som grundar elnätsägarnas godkännande av dessa anläggningar. Rapporten kommer också att undersöka vad som driver en investering av solceller och hur leverantören på bästa sätt dimensionerar solcellsanläggningen för specifika byggnader. Information gällande påverkan på elnätet har samlats in dels från tryckta källor och dels genom intervjuer av personer som idag arbetar med dessa frågor på elnätsbolag. För dimensioneringen av solcellsanläggningar har data samlats in byggnadernas verkliga elförbrukning och sedan har denna sammanställts till ett timmedelvärde som använts i simuleringsprogrammet PVSyst. Kalkyler gällande kostnaden har gjorts utifrån simuleringsprogrammets utdata som har matats in i en LCOE-kalkyl. Arbetet har lett till en sammanställning av vad som verkar vara de största problemen gällande elkvaliteten. Det har även lett till färdiga dimensioneringar och kalkyler av anläggningar i olika verksamheter. Resultatet visar även på om det finns fördelar i att använda öst-/västorientering på panelerna istället för sydorientering. / The report has been carried out in collaboration with Vinnergi, a consulting company in both electricity, fiber and mobile networks. The purpose is to investigate how the electricity grid is affected by the increased number of photovoltaic systems and try to answer what is the basis of the grid owners' approval of these systems. The report will also investigate what drives an investment of solar cells and how the supplier best dimensions the plant for specific systems. Information regarding the impact on the electricity grid has been collected partly from printed sources and partly through interviews of people who are currently working on these issues at electricity grid companies. For the design of photovoltaic systems, data has been collected on the buildings' actual electricity consumption and then compiled to an hourly value used in the PVSyst simulation program. Costs calculations have been made on the basis of the simulation program's output, which has been entered into an LCOE calculation. The paper has resulted in a compilation of what appears to be the biggest problems regarding electricity quality. This has also led to the finished dimensions and calculations of systems in different operations. The result also shows if there are advantages in using east / west orientation on the panels instead of south orientation.
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Development of a methodology to simulate simple mismatching in photovoltaic systems

Frid, Gustav January 2015 (has links)
The currently available tools to simulate solar photovoltaic (PV) systems do not offer a reliable solution to simulate string or module level inverter systems with partial shading and modules with mismatching electrical characteristics. The available methodologies to simulate this satisfying require computational power that is not commonly available. To make it possible to simulate these kinds of systems a methodology based around the software “System Advisory Model” (SAM) is proposed. The methodology assumes that shading is binary, meaning a module can either be fully shaded or not shaded at all. Two different global IV curve models are presented and evaluated in comparison with a more detailed Matlab global IV model based on the one diode equivalent circuit. All these methodologies disregards the impact of the bypass diodes in the PV module and this is considered a significant error, which has to be quantified. It is proposed that this should be done by using the two-diode equivalent circuit instead of the one diode model. Finally the methodology is not concluded to be reliable until verified in comparison with real world data. / De för närvarande tillgängliga simuleringsverktygen för solcellssystem erbjuder inte en tillförlitlig metod för simulering av delvis skuggade system eller system med moduler med olika elektriska egenskaper. De metoder som är tillgängliga för att simulera detta tillförlitligt kräver datorkraft som inte är allmäntillgänglig. För att göra det möjligt att simulera dessa typer av system föreslås en metod baserad kring programvaran "System Advisory Model" (SAM). Metoden utgår från antagandet att skuggning är binärt, vilket innebär att en modul kan antingen vara helt skuggad eller inte skuggad alls. Två olika globala IV-modeller presenteras och utvärderas i jämförelse med en detaljerad Matlab global IV-modell baserad på enkel-diods ekvivalenta kretsen. Denna metod bortser dock från effekterna av bypass-dioderna i PV-modulen och detta antas medföra betydande fel som måste kvantifieras, detta bör då göras med hjälp av två-diods ekvivalenta kretsen. Slutligen så kan metoden inte anses pålitlig förrän den har blivit verifierad med verkliga data.
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Analyse et commandes des convertisseurs multi-niveaux pour un générateur photovoltaïque connecté au réseau électrique / Analysis and control of multilevel converters for a grid connected photovoltaic generator

Mahamat, Chabakata 19 June 2018 (has links)
Ces travaux de thèse préparés au laboratoire SATIE, s’inscrivent dans la promotion de l’énergie solaire photovoltaïque (PV). Dans ces travaux, nous nous intéressons particulièrement au dimensionnement et au contrôle-commande du système PV connecté au réseau dans un contexte d’utilisation au Tchad où l’on doit tenir compte des problématiques du coût, du rendement, de fiabilité du système et de la qualité de l’énergie. Le réseau considéré est un réseau basse tension BT (220 V) avec une fréquence égale à 50 Hz mais susceptible de varier, auquel on injecte une puissance de 5,2 kW. Une méthode de dimensionnement des éléments passifs du filtre, a été préposée en premier lieu. Dans le but de réduire le coût de fabrication et le volume du filtre passif, une technique de fragmentation en plusieurs petites inductances en série a été adoptée. Cette technique optimise le volume et le coût du système PV classique. Ensuite, nous avons proposé une nouvelle architecture du système PV connecté au réseau utilisant un onduleur multi-niveaux. L’adaptation de cet onduleur à structure innovante a permis de réduire le coût de fabrication du filtre passif d’environ 40 % par rapport au système classique optimisé, tout en augmentant le rendement. Enfin, une commande PQ découplée, utilisant une boucle à verrouillage de phase PLL pour synchronisation, a été conçue et appliquée aux deux systèmes PV. Elle est bien adaptée au système avec onduleur multi-niveaux. / This PhD work, prepared at SATIE laboratory, is part of the promotion of solar photovoltaic (PV) energy. In this work, we are particularly interested in design and control of the grid-connected PV system in a context of use in Chad where cost, reliability, efficiency, and energy quality issues of the system should be taken into account. The considered grid is a low voltage grid (220 V) with a frequency equal to fifty hertz (50 Hz) but likely to vary, in which a power of five point two ( 5.2 kW) is injected. A design method of the filter passive to reduce the filter elements is proposed firstly. In order to reduce manufacturing cost and volume of the passive filter, we apply a technique consisting of dividing each inductance value and making it in several small inductances in series. This technique optimizes the conventional PV system. Then, we proposed a new grid-connected PV system architecture using a multi-level inverter. The adaptation of this innovative structure has reduced the manufacturing cost of passive filter by nearly 40 % compared to the classical optimized system. Finally, a decoupled PQ control, using a phase locked loop for sysnchronization, has been designed and applied for both systems. It is well adapted to the system with multilevel inverter.

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