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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.
121

Estratégia de planejamento de produção e os sistemas ERP em ambientes sujeitos ao fenômeno hockey-stick. / Production planning strategy and ERP systems in environments subject to the hockey-stick phenomenon.

Renato Gioielli Basso 18 August 2015 (has links)
O ambiente competitivo atual tem colocado pressão no processo de tomada de decisão no mundo corporativo. Os trade-offs das prioridades competitivas discutidos na elaboração da estratégia como custo, qualidade, serviço e flexibilidade já não são suficientes. Estes trade-offs, embora importantes no curto prazo, devem ser compatibilizados de modo que as empresas que tenham o melhor balanço entre eles devam ter resultado superior. Um dos trade-offs bastante discutido é o equilíbrio entre serviço e estoque. A percepção é que seja improvável alcançar excelência no serviço sem ter um considerável nível de estoque. Deste cenário nasce então o paradoxo do uso de sistemas MRP (Material Requirement Planning) versus sistemas JIT (Just in Time), ou melhor, sistemas empurrados versus puxados, já que a escolha por um ou outro sistema tem ligação íntima com a gestão de estoque. Se por um lado os sistemas MRP são largamente utilizados, via softwares ERP, por outro sistemas JIT têm trazido importantes melhorias nos resultados. Embora muitas empresas considerem a adoção exclusiva de um ou outro sistema, algumas delas têm adotado um processo híbrido com o objetivo de tirar o melhor de cada sistema e gerar assim desempenho superior. O objetivo deste trabalho é investigar como as empresas inseridas em mercados caracterizados pela concentração de demanda no final do mês (fenômeno conhecido como hockey-stick), e baixo acerto nas previsões de demanda, estão aplicando suas estratégias de planejamento de produção e seus ERP. Se por um lado a baixa acurácia nas previsões causa um problema na aplicação de estratégias empurradas de planejamento, pois requer um alto estoque de segurança associado, por outro a concentração de embarque dificulta a adoção de uma estratégia puramente puxada, já que o sistema não tem a estabilidade necessária. Para cumprir com este objetivo seis estudos de caso foram conduzidos e os resultados encontrados, suportados pela teoria, sugerem o aparecimento de um modelo híbrido eficaz para planejamento no ambiente estudado assim como o aparecimento de um sistema DSS (Decision Support System). Outra contribuição desta pesquisa foi identificar, em um dos casos, uma empresa que conseguiu atacar de maneira eficaz o fenômeno em sua causa raiz neutralizando assim seus efeitos. / The highly competitive environment of modern times has put pressure on the decision-making process in the corporate world. The trade-offs of competitive priorities such as cost, quality, service and flexibility are no longer enough. These trade-offs, albeit important in the short term, must be matched so that companies that have the best balance between them should have superior results. One of the tradeoffs widely discussed is the balance between service level and inventory. The perception is that excellence is not likely to be achieved in service without having a significant level of inventory. From this scenario comes the paradox of using MRP systems (Material Requirement Planning) versus JIT systems (Just in Time), or rather \"pushed\" systems versus \"pulled\" systems since the option for one or the other system has a close connection with inventory management. On the one hand, MRP systems are widely used in industry through ERP software; on the other hand, JIT systems have obtained better results. While many companies consider adopting one or another system, some of them adopt a hybrid process with the goal of taking the best of each system and generate superior performance. The purpose of this research is to investigate how companies inserted in markets characterized by sales peak at the end of the month (hockey-stick phenomenon), and low accuracy in demand forecasts, are applying their production planning strategies and their ERP. Low forecast accuracy causes a problem in applying pushed strategies as it requires a high safety stock associated. Conversely, the sales peak hinders the adoption of a purely pull strategy since the system does not have the necessary stability. To meet this goal, six case studies were conducted and the results found and supported by the theory suggest the emergence of an effective hybrid model for planning in the environment studied as well as the appearance of a DSS (Decision Support System). Another contribution of this research was to identify in one of the cases a company that managed to effectively tackle the phenomenon in the root cause, neutralizing its effects.
122

Analise das proteinas Ki-1/57 e PRMT1 : identificação, mapeamento e caracterização funcional da interação com outras proteinas / Analysis of the proteins Ki-1/57 and PRMT1: identification, mapping and characterization of the interaction with other proteins

Passos, Dario Oliveira dos 31 August 2006 (has links)
Orientador: Jorg Kobarg / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-07T08:03:42Z (GMT). No. of bitstreams: 1 Passos_DarioOliveirados_D.pdf: 4831709 bytes, checksum: 0aa3e031d4e82dc447636416b68401e8 (MD5) Previous issue date: 2006 / Resumo: A proteína Ki-1/57 que é encontrada tanto no núcleo quanto no citoplasma está associada com atividade de proteína quinase serina/treonina e é fosforilada nestes resíduos após ativação celular. Neste trabalho verificamos que Ki-1/57 interage com a proteína Chromatin-Helicase-DNA-binding domain 3 (CHD3) e com a proteína adaptadora/sinalizadora RACK1 no núcleo. Pelo sistema do duplo híbrido de levedura (SDHL) a proteína arginina metiltransferase 1 (PRMT1) foi selecionada como outra proteína de interação. A PRMT1 integra uma família representada por nove enzimas humanas que catalisam reações de metilação em resíduos de arginina. Em seguida, usando agora a PRMT1 como isca - no SDHL - identificamos as proteínas Ki-1/57 e hnRNPQ, juntamente com outras 13. A maioria delas contêm motivos ¿RGG-box¿ em suas seqüências de aminoácidos, que são conhecidos alvos para metilação. Posteriormente verificamos que Ki-1/57 e seu provável parálogo CGI-55 conservam dois motivos ¿RGG/RXR-box¿ e que são substratos in vitro para a metilação de argininas pela PRMT1. Estudos de mapeamento mostraram que todos os fragmentos contendo o motivo ¿RGG/RXR-box¿ interagem com a PRMT1 e são alvos à metilação in vitro. Ki-1/57 endógena, imunoprecipitada de células L540, mostrou ser metilada in vivo, além de ser um alvo a metilação pela PRMT1 in vitro, somente quando as células são previamente tratadas com o inibidor da metilação Adox. Tratamento das células Hela com o inibidor da metilação (Adox) causa desaparecimento da imuno-marcação citoplasmática de Ki-1/57 e relativa redistribuição do parálogo CGI-55 para o citosol. Assim, pode ser especulado que a metilação destas proteínas deve ser um evento importante para suas localizações subcelulares e conseqüentemente para suas funções. Em resumo, nossos dados sugerem que o SDHL é um método efetivo na identificação de novos substratos celulares para a PRMT1 e poderia ser estendido para a identificação e caracterização de novos substratos para os outros integrantes da família das PRMTs humanas / Abstract: The protein Ki-1/57 that is found both in the cytoplasm and nucleus is associated with serine/threonine protein kinase activity and gets phosphorylated on serine and threonine residues upon cellular activation. We demonstrated that Ki-1/57 interacts with the Chromatin-Helicase-DNA-binding domain protein 3 (CHD3) and with the adaptor/signaling protein RACK1 in the nucleus. By utilizing the yeast two-hybrid system (YTHS), we were further able to find the protein arginine-methylatranseferase-1 (PRMT1) as another interacting protein. PRMT1 is a member of the family constituted by 9 human enzymes that catalyze methylation reactions on arginine residues. Afterwards, by using PRMT1 as bait in the YTHS we identified both Ki-1/57 and NSAP1 as interacting proteins, along with 13 other proteins. The majority of them present RGG-box clusters in their amino acid sequences, which are known to be targets for arginine methylation. We further found that Ki-1/57 and its putative paralogue CGI-55 have two RGG/RXR-box clusters conserved between them and that they are substrates for arginine-methylation by PRMT1 in vitro. In mapping studies, we observed that all Ki-1/57 protein fragments containing the RGG/RXRbox clusters interact with PRMT1 and are targets for methylation in vitro. Endogenous cellular Ki-1/57 seems to be methylated in vivo and is a target for methylation by PRMT1 in vitro, only when cells have been previously treated with the methylation inhibitor Adox. Treatment of Hela cells with the inhibitor of methylation (Adox) causes the disappearance of the immuno-staining of Ki-1/57 in the cytoplasm and a relative redistribution of the paralogue CGI-55 to the cytosol. It can therefore be speculated that the methylation of these proteins is important for their sub-cellular localization and in consequence for their function. In summary our data suggest that the YTHS is an effective method for the identification of novel cellular PRMT substrates and could be extended for the identification and characterization of novel substrates to the other components of the human PRMT1 family / Doutorado / Bioquimica / Doutor em Biologia Funcional e Molecular
123

Estudo funcional e estrutural de Nip7p, uma proteina conservada envolvida na sintese de ribossomos / Functional and structural analysis of Nip7p, a conserved protein involved in ribosome biogenesis

Coltri, Patricia Pereira 12 October 2007 (has links)
Orientador: Nilson Ivo Tonin Zanchin / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-09T15:29:14Z (GMT). No. of bitstreams: 1 Coltri_PatriciaPereira_D.pdf: 4564852 bytes, checksum: f11b831da981a8969c20f8f03ae8c617 (MD5) Previous issue date: 2007 / Resumo: A síntese de ribossomos é um processo conservado em eucariotos e se inicia com a transcrição dos rRNAs no nucléolo. Mais de 170 fatores atuam de forma transitória no processamento dos precursores para gerar os rRNAs maduros que formarão as subunidades ribossomais no citoplasma. Entre as proteínas envolvidas na síntese de ribossomos está a Nip7p, uma proteína nucleolar de 21 kDa associada ao complexo pré-60S em Saccharomyces cerevisiae. Nip7p é conservada e possui ortólogas em eucariotos e em Archaea. A análise da seqüência primária revela a presença de um domínio conservado na região C-terminal, denominado PUA, encontrado em diversas proteínas associadas a modificações no RNA. Neste trabalho, foram realizadas análises estruturais e funcionais com o objetivo de investigar a função molecular da proteína Nip7 no processamento e modificação do rRNA. A estrutura tri-dimensional de PaNip7, ortóloga de Nip7p em Pyrococcus abyssi foi resolvida por difração de raios-X até 1,8Å de resolução, utilizando o método SIRAS. Comparação estrutural seguida por ensaios in vitro confirmaram o envolvimento do domínio PUA na interação com RNA. Além disso, tanto Nip7p como suas ortólogas PaNip7 e HsNip7 interagem com seqüências ricas em uridina, indicando que atuam de forma semelhante no processamento do rRNA. Essa preferência por uridina pode ainda explicar a afinidade da proteína Nip7p de S. cerevisiae pelo RNA da região ITS2, conforme observado em ensaios de interação utilizando UV-crosslinking. De fato, uma análise funcional realizada por primer extension comprovou que ocorre um bloqueio no processamento da região espaçadora ITS2 na ausência de Nip7p. Nip7p interage com várias proteínas do complexo pré-60S, entre as quais Nop8p e Nop53p, ambas associadas ao processamento do pré-27S. Embora os ensaios de co-purificação tenham confirmado a interação com as proteínas do complexo H/ACA box, deficiência em Nip7p não afeta a pseudo-uridinilação do rRNA. O duplo-híbrido realizado com a ortóloga humana de Nip7p, HsNip7, revelou interações com FTSJ3 e com a proteína SUMO-2. A interação direta de HsNip7 com estas proteínas foi confirmada por ensaios in vitro. HsNip7 e FTSJ3 colocalizaram na região nucleolar de células HEK293. FTSJ3 é uma proteína não caracterizada que possui o domínio FtsJ, descrito inicialmente para rRNA metiltransferases de procariotos. Além disso, FTSJ3 apresenta similaridade de sequência à proteína Spb1p de levedura, cuja função na metilação do rRNA 25S na posição Gm2922 já foi estabelecida. Embora a Nip7p não interaja com a Spb1p, estes dados indicam que FTSJ3 deve ser a ortóloga humana da Spb1p. As proteínas SUMO estão envolvidas na modificação pós-traducional (sumoylation) que regula a localização subcelular de proteínas. Em levedura, a provável ortóloga de SUMO, Smt3p, foi descrita na partícula pré-60S, portanto a interação HsNip7-SUMO-2 pode ser específica. Estes dados sugerem que as proteínas atuem no mesmo complexo da formação da subunidade 60S também em células humanas / Abstract: Ribosome biogenesis is conserved throughout eukaryotes and takes place in the nucleolus, a specialized nuclear compartment where the rRNA precursors are transcribed. More than 170 trans-acting factors coordinately interact to generate the mature rRNAs. Among the proteins identified in the pre-60S particle in Saccharomyces cerevisiae is Nip7p. Highly conserved Nip7p orthologues are found in all eukaryotes and Archaea. The analysis of Nip7p sequence reveals a conserved C-terminal domain named PUA, also found in a number of RNA-interacting proteins. In this work, we performed structural and functional analysis to investigate Nip7p molecular role on rRNA processing and modification. The structure of Pyrococcus abyssi Nip7p ortholog, PaNip7, was solved using X-ray diffraction data to 1,8Å resolution. Structural analysis followed by in vitro assays confirmed the involvement of PUA domain in RNA interaction. S. cerevisiae Nip7p and its archaeal and human counterparts show preference for binding uridine-rich sequences, indicating conserved functional features among the orthologues. The preference for uridine can explain the higher affinity of S. cerevisiae Nip7p for ITS2 sequence, as observed by UV-crosslinking assays. Consistently, functional analysis revealed pre-rRNA processing in the ITS2 region is seriously impaired. Yeast two-hybrid analysis confirmed by pull down assays revealed Nip7p interacts with Nop8p and Nop53p, two nucleolar proteins involved in pre-27S processing and components of pre-60S particle. Although yeast two-hybrid and pull down assays indicated that Nip7p interacts with H/ACA box core proteins, pseudouridylation is not affected under conditions of Nip7p depletion. In addition, yeast two-hybrid analysis confirmed by GST-pull down revealed HsNip7 interaction with FTSJ3 and SUMO-2. Both HsNip7 and FTSJ3 showed nucleolar subcellular localization in HEK293 cells. FTSJ3 is an uncharacterized protein containing the FtsJ domain, initially described in prokaryotic rRNA methyl-transferases. FTSJ3 shows sequence similarity to yeast Spb1p, an rRNA methyl-transferase involved in methylation of Gm2922, indicating that FTSJ3 may be the human orthologue of Spb1p. Sumoylation is a post-transcriptional covalent modification involved in regulation of protein subcellular localization. Putative yeast orthologues of SUMO, such as Smt3p, have been described in the pre-60S ribosomal particle, suggesting that SUMO-2 might play a specific role in 60S subunit biogenesis / Doutorado / Genetica Animal e Evolução / Doutor em Genetica e Biologia Molecular
124

O interactoma de Stanniocalcina-1 humana sugere novas funções e vias de atuação celulares / The interactome of human Stanniocalcin-1 suggests new cellular functions and pathways

Santos, Marcos Tadeu dos, 1984- 19 August 2018 (has links)
Orientador: Jörg Kobarg / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-19T01:34:02Z (GMT). No. of bitstreams: 1 Santos_MarcosTadeudos_D.pdf: 15943486 bytes, checksum: 39810fdf0ace76e5e8963354bdc460ca (MD5) Previous issue date: 2011 / Resumo: O objetivo deste projeto foi estudar genes ativados em células do estroma da medula óssea, induzidos pela co-cultura com blastos leucêmicos, na tentativa de uma melhor compreensão sobre o crostalk entre estas células no microambiente tumoral. Nós identificamos Stanniocalcina-1 (STC1) como um potencial marcador molecular do microambiente tumoral, uma vez que sua expressão foi aumentada cerca de 7 vezes em células do estroma co-cultivadas com blastos leucêmicos primários. STC1 humana é uma glicoproteína secretada e tem sido descrita participando em diferentes processos fisiológicos, incluindo a angiogênese, hipóxia e principalmente, a carcinogênese. Nós produzimos a proteína recombinante STC1 no sistema baculovírus e também anticorpos monoclonais, usados em um ensaio ELISA, que agora será testado como um novo kit de diagnóstico de leucemia por uma empresa brasileira. Além disso, identificamos novos parceiros de interação para STC1 através do sistema de duplo hibrido em levedura sendo que algumas destas interações foram confirmadas por GST-pull down. A região Nterminal foi identificada como sendo a região responsável pela interação de STC1 com seus parceiros. Estudos de localização sub-celular por microscopia, revelaram uma deposição ubíqua citoplasmática e puntiforme nuclear, lembrando corpúsculos nucleares relacionados a SUMOilação. Embora STC1 interaja com a proteína SUMO1 e tenha uma predição de alta probabilidade para ser SUMOilada, ensaios in vitro e in vivo não conseguiram detectar STC1 SUMOilada. No entanto, observamos que STC1 regula a SUMOilação de forma significativa em três outras proteínas. Essas descobertas sugerem um novo papel para STC1 no ciclo de SUMOilação, agindo como uma SUMO E3 ligase. Observamos também que STC1 possui um receptor na membrana plasmática em linhagem de células leucêmicas K562 e que a incubação de STC1 com outras células leucêmicas parece favorecer a proliferação destas células ao passo que estimula uma maior produção da própria STC1 intracelular em células do estroma. Juntos, todos estes resultados abrem novas pistas promissoras a serem exploradas no futuro, uma vez que todos os resultados mostram ligações interessantes com estudos funcionais anteriores em STC1 / Abstract: The aims of this project is to study upregulated genes on bone marrow stromal cells, induced by the co-culture with leukemic blasts, trying to have a better understand about the crosstalk between these cells in the tumor microenvironment. We identified Stanniocalcin-1 (STC1) as a putative molecular marker for the leukemic microenvironment, once its expression was increased around 7 times in stromal cells co-cultivated with primary leukemic blasts. Human STC1 is a secreted glycoprotein that has been implicated in different physiological process, including angiogenesis, hypoxia and mainly in carcinogenesis. We produced the recombinant protein STC1 in baculovirus system and monoclonal antibodies for an ELISA assay that now will be tested as a new leukemia diagnostic kit by a Brazilian company. Moreover, we identified new interacting protein partners for STC1 by yeast two hybrid system and some of these interactions were confirmed by GST-pull down assays. The N-terminal region was mapped to be the region that mediates the interaction between STC1 and its partners. Microscopic subcellular localization, revealed an ubiquitous cytoplasmic and dot-like nuclear deposition, resembling SUMOylation related nuclear bodies. Although STC1 interacts with SUMO-1 and has a high theoretical prediction score for a SUMOylation site, in vitro and in vivo assays could not detect STC1 SUMOylation. However, we found that STC1 significantly regulates the SUMOylation of three other proteins. These ??ndings suggest a new role for STC1 in SUMOylation cycle, acting as a SUMO E3 ligase. We either observe that STC1 has a plasmatic membrane receptor in K562 leukemic cell lines and the incubation of STC1 with other leukemic cells suggest a increase of proliferation of these cells and stimulates the production of more intracellular STC1 at stromal cells. Together, all of these findings open promising new avenues to be explored in future detailed studies, since they all show interesting connections with previous functional studies on STC1 / Doutorado / Genetica Animal e Evolução / Doutor em Genetica e Biologia Molecular
125

Intelligent Algorithms for a Hybrid FuelCell/Photovoltaic Standalone System : Simulation Of Hybrid FuelCell/Photovoltaic Standalone System

Shah, Syed Fawad Ali January 2010 (has links)
The Intelligent Algorithm is designed for theusing a Battery source. The main function is to automate the Hybrid System through anintelligent Algorithm so that it takes the decision according to the environmental conditionsfor utilizing the Photovoltaic/Solar Energy and in the absence of this, Fuel Cell energy isused. To enhance the performance of the Fuel Cell and Photovoltaic Cell we used batterybank which acts like a buffer and supply the current continuous to the load. To develop the main System whlogic based controller was used. Fuzzy Logic based controller used to develop this system,because they are chosen to be feasible for both controlling the decision process and predictingthe availability of the available energy on the basis of current Photovoltaic and Battery conditions. The Intelligent Algorithm is designed to optimize the performance of the system and to selectthe best available energy source(s) in regard of the input parameters. The enhance function of these Intelligent Controller is to predict the use of available energy resources and turn on thatparticular source for efficient energy utilization. A fuzzy controller was chosen to take thedecisions for the efficient energy utilization from the given resources. The fuzzy logic basedcontroller is designed in the Matlab-Simulink environment. Initially, the fuzzy based ruleswere built. Then MATLAB based simulation system was designed and implemented. Thenthis whole proposed model is simulated and tested for the accuracy of design and performanceof the system.
126

Etude de la solubilité de l’hydrogène dans des liquides confinés / Study of hydrogen solubility in nano-liquid confined

Clauzier, Stéphanie 18 December 2012 (has links)
L’adsorption des gaz dans les solides micro/mésoporeux et la solubilisation des gazdans les liquides sont des phénomènes physiques très bien connus. En revanche, lasolubilisation des gaz dans un liquide confiné à l’intérieur d’un solide (système hybride) estun domaine très peu étudié, malgré des applications importantes, notamment dans l’extractiondu pétrole, les ciments ou encore les réacteurs catalytiques triphasiques. Nous avons montréexpérimentalement que la solubilité du CO2 et H2 augmente quand la taille de pores du solideest de l’ordre du nanomètre. Un des objectifs de cette thèse était d’optimiser le couple solidesolvant(système hybride) et les conditions de température et de pression pour augmenter lestockage de H2 pour les applications de stockages. Dans le système Aérogel/éthanol à 50 barset 0°C, la solubilité de H2 est 8,5 fois supérieure à la solubilité mesurée dans le liquide seul,représentant une masse de 6,2g d’hydrogène stocké par kg de solide. Le second objectif étaitde comprendre les paramètres clefs de ce phénomène apparent de « sursolubilité » dans lessystèmes hybrides. En comparant différents solides poreux (zeolithes, MOF, MCM, silice),nous avons montré le rôle majeur des propriétés d’interfaces. Les phénomènes desolubilisation ont été modélisés à l’échelle moléculaire par GCMC et validéesexpérimentalement. Il apparait que le mécanisme de sursolubilisation provient d’unestructuration en couche des molécules de solvants en interactions avec les parois dumésopore. / The adsorption of gases in micro/mesoporous materials and solubility of gases inliquids are physical phenomena well known. On the other hand, solubility of gases in liquidsconfined inside a solid (hybrid system) has not been entensively studied, despite the importantapplications such systems can have in the areas of oil extraction, cement and triphasiccatalytic reactors. We have shown experimentally that the solubility of CO2 and H2 increaseswhen the size of the pores of the solid is in the nanometer range. One of the objectives of thisthesis was to optimize the couple a solid and a solvent into a hybrid system and the conditionsin which to increase the H2 storage capacity. In an aerogel/ethanol hydrid system at 50 barand 0 ° C, the solubility of H2 is 8.5 times greater than the solubility measured in the singleliquid, representing a mass of 6.2 g of hydrogen stored per kg of solid. The second objectivewas to understand this apparent phenomenon of oversolubility and the key parameters in thehybrid systems. By comparing different porous solids (zeolites, MOFs, MCM-41 and silica),we have shown the major role of the properties of interfaces. The phenomena of solubilsationwas modelled by GCMC and experimentally validated. It appears that the mechanism ofoversolubilisation comes from structuring the solvent molecules in interactions with the wallsof the mesopore layered.
127

Návrh fotovoltaického systému rodinného domu / Design of photovoltaic system for a family house

Darebný, Tomáš January 2017 (has links)
Basic knowledge of photovoltaic energy transformation, devices and materials, used in photovoltaic are summarized in this master's thesis. The main goal of this thesis is orientation in the photovoltaic systems used these days and explain advantages and disadvantages of these systems during the design phase.
128

Sistema híbrido solar-eólico-biogás incluindo produção, armazenamento e uso dinâmico de hidrogênio /

Moura, Carlos Henrique Silva January 2020 (has links)
Orientador: José Luz Silveira / Resumo: A inserção de fontes alternativas e confiáveis de energia na sociedade brasileira vem ganhando destaque e crescente importância, contudo, ainda é um grande desafio, visto que a sociedade ainda é majoritariamente dependente de combustíveis fósseis. Os impactos ambientais causados por eles são prejudiciais à vida humana e ao meio ambiente, além de confirmar a urgência da aplicação de tais tecnologias em diferentes cenários da sociedade. O hidrogênio, como vetor energético, vem ganhando destaque e aplicações dentro dos mais variados setores da sociedade, principalmente no setor de transporte como combustível. Dado ao exposto, esse trabalho tem como objetivo analisar a produção de hidrogênio renovável para uso como combustível veicular. A metodologia para a análise técnica consistiu em obter o consumo de energia elétrica para produção do hidrogênio, para assim com base nos recursos solares, eólicos e de biogás de São Paulo (SP), realizar o balanço energético e desta forma dimensionar o sistema híbrido. Baseado nos resultados técnicos, a metodologia econômica permitiu analisar a viabilidade financeira de implementar o sistema híbrido dimensionado permitindo determinar o nível de investimento, o custo da energia elétrica gerada, o custo do hidrogênio gerado e o período de retorno do investimento. A análise ambiental fundamentou-se em determinar a eficiência ecológica considerando os sistemas geradores de eletricidade para o processo de eletrólise da água. Os resultados obtidos most... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The insertion of alternative and reliable sources of energy in Brazilian society has been gaining prominence and growing importance, however, it is still a great challenge, since society is still mostly dependent on fossil fuels. The environmental impacts caused by them are harmful to human life and the environment, in addition to confirming the urgency of the application of such technologies in different scenarios of society. Hydrogen, as an energy vector, has been gaining prominence and applications within the most varied sectors of society, mainly in the transport sector as a fuel. Given the above, this work aims to analyze the production of renewable hydrogen for use as a vehicle fuel. The methodology for the technical analysis consisted of obtaining the consumption of electric energy for the production of hydrogen, so that, based on the solar, wind and biogas resources of São Paulo (SP), carry out the energy balance and thus dimension the hybrid system. Based on the technical results, the economic methodology made it possible to analyze the financial feasibility of implementing the scaled hybrid system allowing to determine the level of investment, the cost of the electricity generated, the cost of the hydrogen generated and the period of return on investment. The environmental analysis was based on determining the ecological efficiency considering the electricity generating systems for the water electrolysis process. The results obtained show that the proposed hybrid sy... (Complete abstract click electronic access below) / Mestre
129

An Omega-Based Bacterial One-Hybrid System for the Determination of Transcription Factor Specificity

Noyes, Marcus Blaine 20 March 2009 (has links)
From the yeast genome completed in 1996 to the 12 Drosophilagenomes published earlier this year; little more than a decade has provided an incredible amount of genomic data. Yet even with this mountain of genetic information the regulatory networks that control gene expression remain relatively undefined. In part, this is due to the enormous amount of non-coding DNA, over 98% of the human genome, which needs to be made sense of. It is also due to the large number of transcription factors, potentially 2,000 such factors in the human genome, which may contribute to any given network directly or indirectly. Certainly, one of the central limitations has been the paucity of transcription factor (TF) specificity data that would aid in the prediction of regulatory targets throughout a genome. The general lack of specificity data has hindered the prediction of regulatory targets for individual TFs as well as groups of factors that function within a common regulatory pathway. A large collection of factor specificities would allow for the combinatorial prediction of regulatory targets that considers all factors actively expressed in a given cell, under a given condition. Herein we describe substantial improvements to a previous bacterial one-hybrid system with increased sensitivity and dynamic range that make it amenable for the high-throughput analysis of sequence-specific TFs. Currently we have characterized 108 (14.3%) of the predicted TFs in Drosophilathat fall into a broad range of DNA-binding domain families, demonstrating the feasibility of characterizing a large number of TFs using this technology. To fully exploit our large database of binding specificities, we have created a GBrowse-based search tool that allows an end-user to examine the overrepresentation of binding sites for any number of individual factors as well as combinations of these factors in up to six Drosophila genomes (veda.cs.uiuc.edu/cgi-bin/gbrowse/gbrowse/Dmel4). We have used this tool to demonstrate that a collection of factor specificities within a common pathway will successfully predict previously validated cis-regulatory modules within a genome. Furthermore, within our database we provide a complete catalog of DNA-binding specificities for all 84 homeodomains in Drosophila. This catalog enabled us to propose and test a detailed set of recognition rules for homeodomains and use this information to predict the specificities of the majority of homeodomains in the human genome.
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The electricity demand andsupply in El Espino : Alternatives for diversification of renewabletechnologies / Energitillförseln i El Espino : Alternativ för diversifiering av förnybara energiteknologier

Granqvist, Jessica, Gao, Lily January 2019 (has links)
The use of alternative fuels, particularly renewable energy sources, has been an important strategy to achieve greenhouse gas emission reductions. In Bolivia, many rural areas struggle with an unreliable power supply. The most common electricity solution in such isolated areas is to have off-grid systems, where hybrid systems have become a feasible solution. In this study, a hybrid system in the rural village El Espino is optimized using a linear programming tool called MicroGridsPy. Currently, the village is powered by a hybrid system consisting of solar photovoltaics, a diesel generator and lead-acid batteries as a storing system. To optimize the system in a sustainable way, considering economic, environmental and social aspects, two wind turbines of the nominal capacities 5 and 10 kW are studied and introduced to the hybrid system. To find synergies between the wind and solar energy, the irradiance and wind speed of the study area are simulated using a Weather Research and Forecasting (WRF) model. The power output from the wind turbines can then be obtained by modelling the power curves and then be added to the optimization model. The optimization is performed both with and without the wind turbines to evaluate the impact of them. In the optimization model, characteristics of the components, techno-economic parameters, including investment costs, and constraints such as renewable penetration, and cost of the curtailment are set. The obtained results include that the wind speed is higher during the winter season, and that the wind power output, regardless of turbine size, is proportional to the wind speed. Furthermore, the 10 kW wind turbine is proven to be the most suitable for the system of the two compared. The economical values of the system, such as NPC and LCOE are higher, the higher the renewable penetration, but lower for the system with wind turbines. This implicates that adding wind energy to the hybrid system could be beneficial from both an environmental and economical point of view. One conclusion that can be drawn is that wind turbines are a feasible technology for rural electrification, and that the optimization tool is sensitive to cost. Furthermore, it is found that the wind and solar energy are suitable complements to each other both season wise and daily. / Användningen av alternativa bränslen, särskilt förnybara energikällor, har varit en viktig strategi för att minska utsläppen av växthusgaser. I Bolivia kämpar många landsbygdsområden med en opålitlig strömförsörjning. Den vanligaste lösningen för elektricitet i sådana områden är off-grid system, där hybridsystem har blivit en lämplig lösning. I denna studie, optimeras ett hybridsystem beläget i byn El Espino, med ett linjärt programmeringsverktyg; MicroGridsPy. För närvarande drivs byn av ett hybridsystem bestående av solceller, en dieselgenerator och blybatterier för att lagra energin. För att optimera systemet på ett hållbart sätt, utifrån ett ekonomiskt, miljömässigt och socialt perspektiv, studeras två vindturbiner med de nominella kapaciteterna 5 och 10 kW, för att sedan introduceras till hybridsystemet. För att göra detta simuleras områdets solstrålning och vindhastighet med hjälp av en WRF-modell (Weather Research and Forecast). Effekten från vindturbinerna kan då erhållas genom att modellera effektkurvorna, och kan därefter läggas till i optimeringsmodellen. Optimeringen utförs både med och utan vindturbiner för att på så sätt utvärdera deras inverkan på systemet. I optimeringsmodellen fastställs egenskaper hos komponenterna, techno-ekonomiska parametrar, inklusive investeringskostnader och begränsningar såsom förnybar penetration och kostnad för energispill. De erhållna resultaten visade bland annat att vindhastigheten är högre under vintersäsongen, och att effekten är proportionell mot vindhastigheten, oavsett storlek på vindturbin. Vidare har vindturbinen med kapacitet 10 kW visat sig vara den mest lämpade för systemet av de två jämförda. Systemets ekonomiska värden, såsom NPC och LCOE, är högre, ju högre förnybar penetration, men lägre för systemet med vindturbiner. Detta implicerar att vindenergi kan vara till nytta för hybridsystemet, både ur miljösynpunkt och ur en ekonomisk synvinkel. En slutsats som kan dras är att vindturbiner är en passande teknik för landsbygdselektrifiering, och att optimeringsverktyget som användes är känslig mot kostnader. Vidare konstateras att vind- och solenergi kompletterar varandra både säsongsvis och på daglig basis.

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