Teses de livre-docência - FEIS

URI Permanente para esta coleção

https://hdl.handle.net/11449/109386

Navegar

Agora exibindo 1 - 11 de 11

Texto sistemático crítico evidenciando a evolução das pesquisas realizadas na área de otimização matemática aplicada ao planejamento de sistemas de distribuição de energia elétrica
(Universidade Estadual Paulista (Unesp), 2023-09-14) Baquero, John Fredy Franco [UNESP]
É apresentado um resumo sistemático das pesquisas conduzidas pelo autor no campo do planejamento de sistemas de distribuição de energia elétrica, com foco na aplicação de otimização matemática. Duas linhas principais de pesquisa são abordadas: o planejamento da expansão e o planejamento da operação desses sistemas, empregando modelos de otimização matemática. As contribuições mais significativas concentram-se na melhoria da representação da operação em estado estável dos sistemas de distribuição e sua aplicação em problemas como a expansão e reforço da rede, reconfiguração, restauração e carregamento coordenado de veículos elétricos. Destaca-se que as primeiras propostas abordam a modelagem AC da rede de distribuição, com aprimoramentos subsequentes para considerar o desequilíbrio do sistema. Além disso, um esforço significativo foi dedicado à inclusão e ao aperfeiçoamento, nos modelos matemáticos, da influência de recursos energéticos distribuídos, como geração distribuída intermitente, veículos elétricos, sistemas de armazenamento de energia e, mais recentemente, microrredes elétricas. Ressalta-se a necessidade de novos métodos que auxiliem os planejadores de sistemas de distribuição de energia elétrica a enfrentar os desafios relacionados à integração de recursos energéticos distribuídos na rede de distribuição, lidando com as incertezas inerentes a esses recursos; tais métodos visariam a tomar decisões que evitem investimentos excessivos na expansão da rede, ao mesmo tempo que mantenham a qualidade do serviço para uma alta penetração de recursos energéticos distribuídos. Adicionalmente, é importante considerar o impacto desses recursos e as possibilidades de transações de energia no processo decisório do planejamento, buscando aumentar a participação de múltiplos agentes nos sistemas de distribuição de energia elétrica, o que resultaria em redução de custos e traria benefícios ambientais do uso de energia renovável. Por fim, destaca-se o desafio de desenvolver métodos eficientes que considerem as incertezas inerentes, adotem uma modelagem aprimorada da rede e precisem de um esforço computacional razoável. Essa abordagem levaria uma tomada de decisão mais robusta no planejamento de sistemas de distribuição de energia elétrica.
Nanopartículas de ocorrência natural em latossolo vermelho: caracterização
(2017-08-15) Maltoni, Kátia Luciene [UNESP]; Universidade Estadual Paulista (Unesp)
De ocorrência comum nos solos, as nanopartículas desempenham importante papel em processos relacionados à gênese, aos ciclos biogeoquímicos dos elementos, ao transporte e biodisponibilidade de elementos químicos e, em alguns casos, o destino final de nutrientes e contaminantes naturais ou antropogênicos dos solos. A percepção de que estes minerais tem seu tamanho em escala nano pressupõe superfície específica elevada, o que pode aumentar a adsorção de fósforo, carbono, em algumas situações de arsênio, entre outros compostos e ânions. Para estudar estas partículas é necessário separa-las do solo, o que foi feito, com sucesso, a partir de uma sequência de processos de dispersão e centrifugação. O mapeando químico deste material realizado com MET e EDX, mostrou coincidência em vários mapas da presença do P associado à ocorrência dos óxidos de Fe e Ti, particularmente Hematita e Anatásio. A partir dos dados do DRX foi possível calcular o tamanho dos cristais de caulinita e hematita do material < 100 nm e na fração argila, isto é, < 2000 nm, 16,6 e 25,7 nm respectivamente. Para hematita as medidas foram 13,3 e 21,3 nm na fração nano e na fração argila respectivamente. O anatásio e a gibbsita só apareceram na fração entre 2000 e 100 nm, no DRX. Importante destacar que mesmo em escala nanométrica os óxidos de ferro, no caso a hematita apresentam estrutura interna bem definida. A distribuição do P, considerando as nanopartículas mostrou associação com óxidos de Fe e Ti, o que merece ser melhor avaliado.
Texto sistemático crítico evidenciando a evolução das pesquisas realizadas e o seu contexto cronológico na área de produtos naturais e de síntese orgânica
(2022-04-12) Laurentiz, Rosangela da Silva de; Universidade Estadual Paulista (Unesp)
Plants are an inexhaustible source of organic compounds with the most varied chemical structures and biological properties. These compounds are called secondary metabolites and are involved in the secondary metabolism of plants being produced in response to external agents such as predators, parasites, other plants, environmental factors and soil (nutrients). The diversity of biological properties that they present in plants calls attention to a possible application in the control of some diseases that also affect humans and animals. Among the main classes of secondary metabolites produced by plants, lignans became the target of study by several research groups after the discovery of the anticancer properties of podophyllotoxin. Since then, other lignans have been isolated, identified and evaluated for their biological properties. Such properties are strictly related to the chemical skeletons of each subclass, stereochemistry, nature and position of the substituents. Due to the biological properties and the synthetic challenge related to asymmetric centers, numerous methodologies for the synthesis of lignans and derivatives have been proposed in order to obtain molecules that can be used as targets for the development of new drugs. With scientific advances, molecular modeling tools combined with in vitro assays have facilitated the planning of synthetic targets, guiding the synthesis to obtain compounds with greater probability of being active in vivo against the biological target evaluated in silico. In the course of my research, I have worked with plant extracts, natural lignans, total synthesis of lignans, partial synthesis of derivatives of natural lignans, synthesis of heterocyclic analogues of lignans and the biological evaluation of these compounds. For some biological targets, molecular modeling has been used as a guide to define the type of compound to be synthesized and evaluated in vivo. I have used the fruits of Piper cubeba to obtain the cubebin lignan which has been evaluated in several biological assays and used as a starting material for the synthesis of derivatives and other lignans. From this lignan I published many of my scientific articles and even today this compound continues to be a source of inspiration for two other projects that I develop. Lignans have also been the inspiration for the synthesis of heterocyclic analogues that have interesting biological and luminescent properties. In this text, I comment on the scientific articles linked to both the area of natural products and the area of synthesis that I have published in recent years with the aim of highlighting the evolution of the research carried out and its chronological context.
Síntese, caracterização e aplicação de dióxido de titânio em células fotovoltaicas
(2018-07-23) Paula, Fernando Rogério; Universidade Estadual Paulista (Unesp)
Research in photovoltaic cells is highly current and of great importance, as there is a moment of transition between the use of fossil energy resources and renewable energy sources. However, despite the growth in the use of photovoltaic cells as a source of renewable electrical energy, the expansion of its use in a more intensive way comes up against the cost of production. This cost, however, has been decreasing rapidly in recent years, mainly due to research into new active materials for photovoltaic cells. Currently, the rapid and recent expansion of organic materials as active elements in photovoltaic cells places conjugated conductive polymers among the most promising materials. This work developed hybrid organic/inorganic photovoltaic cells using P3HT as the active layer and TiO2 as an acceptor of photogenerated electrons. The results obtained with confocal microscopy on TiO2/P3HT films showed that the TiO2 film effectively acts as an electron acceptor in the exciton dissociation process. This behavior was confirmed by measuring the efficiency of photovoltaic cells. The TiO2 film obtained with the electrodeposition potential of 1.00 V showed the highest efficiency, around 0.76%.
Estudos com a proteína anexina A1 no tratamento de processos tumorigênicos ou inflamatórios
(2018-03-14) Lisoni, Flávia Cristina Rodrigues; Universidade Estadual Paulista (Unesp)
Annexin A1 (ANXA1) is a protein that under normal conditions is expressed in the cytoplasm of different cell types, but particularly abundant in cells directly related to the inflammatory process, such as monocytes, neutrophils and macrophages. ANXA1 and its peptide Ac2-26 act through the receptors FPR1 and FPR2/ALX, mediating biological responses of these molecules. The aim of this thesis was to present the results of studies carried out with the anti-inflammatory protein ANXA1 in the treatment of tumorigenic or inflammatory processes and to compare them with the control group (without treatment). In the accomplishment of these studies, the cells were treated in vitro with the ANXA1 mimetic peptide and then some morphological characteristics (proliferation, migration, invasion, cytotoxicity and cell viability, co-localization) and gene and protein expression were evaluated in order to search for possible pathways for ANXA1 to modulate gene expression. In addition to the antiproliferative action of ANXA1, we also report in our work the action of this protein in the modulation of gene expression. In Chapter 3.1, we observed that exogenous ANXA1 modifies gene expression in culture of laryngeal carcinoma cells (Hep-2). In this work, we report the effects of ANXA1 on gene expression, using genomic analysis in carcinoma and follicular cells of pituitary adenoma (PDFS). In vivo analyzes of the pituitary of wild mice and knockouts for the ANXA1 gene were also used. By Rapid Subtractive Hybridization (RASH) technique performed on cells treated and not treated with the ANXA1 protein or its peptide, the positive regulation of CCR10 gene expression was observed. In chapter 3.2 we observed the antiproliferative response in Hep-2 cells, suggesting that the ANXA1 peptide can trigger the regulation of growth by direct interaction with the FPR/ANXA1 receptor. The peptide may also have activated the endogenous ANXA1 expression, resulting in regulation of growth by an autocrine/paracrine mechanism. The expression of endogenous ANXA1 was also evaluated in tumor cells and in mast cells, in which ANXA1 immunoreactivity was observed showing low regulation in tumors of the larynx and peritumoral cells, compared to the control tissue. In chapter 3.3 we observed that there was also a decrease in the proliferation of cervical cancer cells after treatment with the ANXA1 peptide, acting as a tumor suppressor, possibly through the MAPK/ERK cascade. In addition, the results showed that the treatment resulted in 82 differentially expressed genes (by 11 RaSH). Expression of the ANXA1 protein was decreased in SiHa cells treated with the peptide by ultrastructural immunocytochemical analyzes. The ID1 gene was validated by RT-qPCR, confirming its low expression after treatment with the peptide. Also linked by Ingenuity Sistems were the cell signaling pathways, of which ANXA1 participates, important for tumor development. In chapter 3.4, analyzing the cultured cells of the ARPE-19 cell line, we observed that cell proliferation decreased after induction by LPS and after treatment with the ANXA1 peptide, cell proliferation and migration increased. And by RaSH, 80 genes differentially expressed after treatment were found, of which five genes (LRAT, CTGF, MAP1B, ALDH1A3 and SETD7), due to their functions related to ocular and/or inflammatory diseases, were validated by RTqPCR, but only two of them (LRAT, CTGF) confirmed the low expression. Ingenuity Sistems also connected the cell signaling pathways, of which ANXA1 participates, important for the inflammatory process. In vitro analyzes of the four scientific papers showed that ANXA1 may play an important role in gene cascades and a regulatory role in tumor development and ocular inflammation. Thus, our data point to the importance of the Hep-2, SiHa and ARPE-19 cells as a potential target of the genetic activities involving the action of ANXA1, considering the applications of this protein as a possible therapeutic alternative in laryngeal carcinoma, and in inflammatory eye diseases.
Contribuições ao estudo de remediação de contaminantes de esgoto sanitário com o uso de lemnas
(2019-11-23) Albertin, Liliane Lazzari [UNESP]; Universidade Estadual Paulista (Unesp)
Over the last seven years, our research group has investigated the wastewater polishing of Ilha Solteira with the use of duckweeds to improve the quality of the effluent to be released into the receiving body and to produce biomass with high added value. The research was based on the remediation of organic and emerging pollutants, such as pharmaceutical and personal care products. During this time, we found that the duckweed of the species Landoltia punctata had an excellent adaptation to our climatic conditions and to the wastewater to be treated, also revealing a high biomass production rate that, among other components, has large protein and starch contents, depending on the operating conditions of the treatment. The richness of this biomass makes it possible to be applied as a source of protein for animal feed or as a feedstock for ethanol production. In this way, it is possible to recover nutrients from the wastewater, potential polluters and eutrophication of water bodies, and to value a Wastewater Treatment Plant based on ecological and efficient processes, with low implantation and operation costs and low energy consumption. In this text, a systematized analysis will be presented on the various developments and questions that have arisen throughout the research. The theoretical background, the questions raised and the results obtained will be presented, trying to highlight the contribution in the field of science.
Supercondutividade em tamanhos mesoscópicos
(2018-07-23) Zadorosny, Rafael [UNESP}; Universidade Estadual Paulista (Unesp)
A supercondutividade em escalas nanoscópicas tem sido objeto de estudos há várias décadas. Contudo, com o advento da nanotecnologia e consequente fabricação de materiais com tamanhos nanoscópicos, esta área se tornou bastante atrativa tanto do ponto de vista de novos comportamentos verificados (e uma possível física nova) quanto das possíveis aplicações. Com isso, nesse trabalho serão apresentadas algumas breves revisões bibliográficas no sentido de deixar o texto mais didático. Na sequência, relatar-se-á sobre algumas produções científicas no intuito de evidenciar a evolução das pesquisas realizadas e o seu contexto cronológico.
Calopogonium mucunoides, um modelo de estudo para estresses abióticos em climas tropicais
(2018-06-07) Camargos, Liliane Santos de [UNESP]; Universidade Estadual Paulista (Unesp)
Calopogonium mucunoides is a tropical herbaceous legume whose adaptive capacity low fertility and high acidic soils motivated the beginning of our research, yet during the PhD. After 2007, several works conducted by us resulted in the identification of some aspects of the biological fixation and the nitrogen metabolism of this species in the presence of N-mineral, as well as the tolerance of its symbiotic system to the presence of nitrate and ammonium, its capacity to fix N at different pH ranges, ranging from acid to near neutrality and, yet, its tolerance to potentially toxic elements. Therefore, it is expected to show an overview of the advances obtained about nitrogen metabolism studies in Calopogonium mucunoides and the future perspectives based on metabolic characterization of this species that may open for new approaches and applications.
Solução numérica das equações de Ginzburg-Landau dependentes do tempo: aplicações a materiais supercondutores mesoscópicos
(2018-07-23) Sardella, Edson [UNESP]; Universidade Estadual Paulista (Unesp)
In the first part of this work we review the main aspects of classical field theory. Next, we apply this theory to the derivation of the London and Ginzburg-Landau equations. The phenomenological theories of superconductivity are discussed, where we determine the fundamental lengths, the coherence length and the London penetration depth. We also discuss the thermodynamic critical field for type I superconductors, and the lower and upper critical fields for type II superconductors. The Abrikosov vortex lattice for type II superconductors is also discussed. In the second part, we rewrite the time-dependent Ginzburg-Lanadu equations (TDGL) in terms of the auxiliary fields in order to satisfy the gauge invariance. The TDGL equations written in this form are then discretized using the link-variables method. In the last part, we apply the TDGL theory to superconductors of mesoscopic dimensions for the study of the state of vortices in confined systems.
Análise envoltória de dados para avaliação da eficiência da tilapicultura brasileira
(2019-05-23) Sabbag, Omar Jorge [UNESP]; Universidade Estadual Paulista (Unesp)
Tilapicultura presents an important segment of social and economic development, considering the potential of natural resources in Brazil. The main contribution of this thesis is related to the management process in the main tilapia producing regions of the country, which is not just a question of generating economic indicators. Within this theme, as a proposal to measure an efficiency evaluation, through Data Envelopment Analysis (DEA analysis), the objective of this study was to evaluate the performance of the main poles producing tilapia in Brazil, in order to generate information that effectively contributes to actions aimed at efficiency gains and competitiveness in the productive sector, as well as to find the determinants of inefficiency through the Tobit econometric model. It observed that between the poles there was a variation between 41 and 85% of global efficiency, due to the characteristics of each region, as well as the management of the factors of production. Among the variables that had a positive influence on efficiency were the collective organization, technical assistance and technology adopted; in the same way, absence of technology, assistance, as well as indebtedness were pointed as negative variables to productive performance. It concluded that in the near future, the good manager would be represented by the greater productive efficiency, generating a reduction of its costs and improving its profits in market mishaps in which the producer is a price-taking agent, considering a competitive and growing scenario for national tilapia farming.
Adubação nitrogenada do consórcio milho/braquiária para manutenção do sistema plantio direto no cerrado Sul-Matogrossense
(Universidade Estadual Paulista (Unesp), 2012-02-14) Andreotti, Marcelo [UNESP]; Universidade Estadual Paulista (Unesp)
Como alternativa para aumento da produtividade dos sistemas de produção agrícola, surgiu o Sistema de Integração Lavoura-Pecuária. Desta maneira, o presente trabalho objetivou avaliar para o consórcio milho/Brachiaria submetido a doses de N em cobertura, em um Latossolo Vermelho distroférrico do sul do Estado do Mato Grosso do Sul nas condições de integração lavoura/pecuária, o seguinte: 1) os teores nutricionais e as leituras do índice de clorofila foliar (ICF) em folhas de milho, assim como os respectivos componentes da produção e a produtividade de grãos, objetivando caracterizar a melhor dose de N para o consórcio, e 2) em relação às espécies de Brachiaria, após o consórcio, com o objetivo de nortear a manutenção do SPD pesquisado, efetuaram-se avaliações da produtividade de fitomassa, dos teores nutricionais, da composição bromatológica e da taxa de decomposição da palhada, durante os anos agrícolas 2008/2009 e 2009/2010, na Fazenda de Ensino, Pesquisa e Extensão, da Faculdade de Engenharia - Unesp, Campus de Ilha Solteira, com histórico de oito anos sob SPD. O delineamento experimental utilizado foi o de blocos casualizados, com quatro repetições, em esquema fatorial 2 x 5, sendo duas espécies de Brachiaria (brizantha e ruziziensis) e cinco doses de N (uréia) em cobertura (0, 50, 100, 150 e 200 kg ha-1). A Brachiaria brizantha, no consórcio com o milho, foi a espécie menos competitiva. A adubação nitrogenada utilizada nessa consorciação, até a dose de 200 kg ha-1 de N, incrementou a nutrição, o crescimento, os componentes da produção e a produtividade de grãos do milho. Dessa forma, a adubação nitrogenada deve ser recomendada para o consórcio, e não isoladamente para as culturas. Embora tenha havido uma maior produtividade de massa seca da B. brizantha, a B. ruziziensis apresentou melhor composição bromatológica e...

Navegar

Submissões Recentes