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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.
241

Der Einfluss von Noradrenalin auf Gap Junction Kanäle

Glawe, Inken 24 October 2011 (has links) (PDF)
Gap Junction Kanäle sind wesentlich für die interzelluläre Kommunikation im Herzen. Die wichtigsten kardialen Gap Junction Proteine sind Connexin 43, Connexin 40 und in frühen Entwicklungsstadien Connexin 45. Da Katecholamine eine wichtige Rolle in der kardialen Physiologie bzw. Pathophysiologie spielen, sollte geklärt werden, ob Katecholamine die Expression von Connexin 40 und Connexin 43 beeinflussen. Es wurden neonatale Rattenkardiomyozyten in Zellkultur 24 Stunden mit aufsteigenden Noradrenalinkonzentrationen (1-10000 nM) (physiologischer Agonist für α-und β-Adrenozeptoren) inkubiert. Hier zeigte sich ein signifikanter Anstieg der Connexin 43 Expression, während die Connexin 40 Expression nicht beeinflußt wurde. Um zu zeigen über welchen Adrenozeptor (α oder β) die Hochregulation von Cx 43 durch Noradrenalin erfolgt, wurden die Zellkulturen in zwei weiteren Versuchsreihen zusätzlich mit einem β-Blocker (Propranolol 100µM) bzw. einem α- Blocker (Prazosin 10 µM) über 24 Std. inkubiert. Hier zeigte sich eine deutliche Inhibierung des Noradrenalineffektes durch die Blockade der α-Rezeptoren durch Prazosin. Eine Blockade der β-Rezeptoren hatte keinen inhibitorischen Effekt auf die Hochregulation der Expression von Cx 43 durch Noradrenalin. Es kam hier sogar zu einer verstärkten Expression verglichen mit der Cx 43 Expression unter Noradrenalin ohne Rezeptorblockade. Desweiteren wurde überprüft, ob es auch unter der Behandlung von Sprague– Dawley-Ratten mit einem β-Mimetikum (Isoprenalin) bzw. einem α-Mimetikum (Phenylephrin) zu einer Veränderung der Connexinexpression kommt. Die Western Blot Analysen ergaben hierbei wieder einen α-Rezeptoren vermittelten Effekt, indem es zu einem wesentlichen Konzentrationsanstieg von Connexin 43 unter der Behandlung mit Phenylephrin kam.
242

Onduleur à forte intégration utilisant des semi-conducteurs à grand gap / High density inverter using wide band gap switches

Regnat, Guillaume 11 July 2016 (has links)
Les composants semi-conducteurs à base de matériaux à grand gap (SiC et GaN) présentent des caractéristiques intéressantes pour la réalisation de convertisseurs d’électronique de puissance toujours plus intégrés. Cependant, le packaging des composants traditionnels en silicium ne semble plus adapté pour ces nouveaux composants et apparaît même comme un facteur limitant. Le développement d’un packaging adapté aux caractéristiques des composants à grand gap est alors nécessaire. Les travaux développés dans cette thèse proposent un nouveau packaging tridimensionnel basé sur un procédé de fabrication de circuit imprimé. L’architecture du module est basé sur le concept « Power Chip On Chip » dont le principe de base permet de réduire les perturbations électromagnétiques. Le procédé de fabrication des circuits imprimés offre une grande flexibilité pour le routage en trois dimensions et permet de s’affranchir de l’interconnexion par fil de bonding entre le package et la puce. La démarche de conception du module s’appuie sur une approche multi-physique afin de qualifier le comportement électromagnétique et thermique du module puis de proposer des voies d’optimisation. Un prototype d’un module implémentant quatre cellules de commutation en parallèle, à base de MOSFET SiC, a été produit avec des moyens de production industriels. Les différents tests réalisés valident l’approche retenue dans ce projet mais soulignent également les aspects technologiques à approfondir pour la réalisation d’un module de puissance industriel. / Wide-band-gap (WBG) semiconductors (SiC and Gan) offer interesting characteristics to realize high density power electronics converters. Conventional packaging used for silicon devices is no more adapted for those now components. Development of dedicated packaging for WBG devices is absolutely required. This PhD thesis presents a new 3D package based on Printed Circuit Board (PCB) industrial process. The module architecture is based on “Power Chip On Chip” concept which allows reducing electromagnetic perturbations. PCB fabrication process offers high design flexibility in three dimensions and allows removing wire bonding to interconnect power die and package. The power module design process is buit on multi-physics design tools in the aim to quantify electromagnetic and thermal behavior of the module. Furthermore, several optimization parameters are highlighted. A power module prototype, with four commutation cells in parallel based on SiC MOSFET, has been produced thanks to industrial facilities. Tests realized on new power module confirm the validity of the concept but furthermore to highlight critical technological parameters to realize an industrial power module.
243

Role of the Histamine Releasing Factor (HRF) in Plasmodium parasite transmission and disease pathogenesis / Rôle de la protéine Histamine Releasing Factor (HRF) dans la transmission du parasite Plasmodium et dans le développement de la pathogénèse de la maladie

Demarta-Gatsi, Claudia 22 November 2016 (has links)
De études récentes suggèrent une forte relation entre susceptibilité au paludisme et réponse allergique. Des niveaux élevés d’histamine plasmatique et tissulaire ont été associés à la sévérité de la maladie chez l’homme infecté par P. falciparum et dans de nombreux modèles animaux. Histamine releasing factor (HRF), une protéine pro-inflammatoire libérant l'histamine au cours des processus allergiques, est produite par le parasite au cours des infections palustres modérées et sévères, suggérant l’implication du HRF dans l’altération des réponses immunitaires et dans la pathogenèse. Les objectifs de ce travail consistaient à évaluer le rôle de la protéine parasitaire HRF dans le développement de la réponse immunitaire et à déterminer si son expression est associée à la sévérité de la maladie en étudiant deux parasites murins, PbANKA et PbNK65, déficients pour la protéine HRF (hrfΔ). Les souris infectées avec des sporozoïtes PbANKA-hrfΔ ont montré une diminution de la fréquence du neuropaludisme associée à un déficit du développement des parasites mutants au cours du stade hépatique et à une augmentation précoce systémique d’IL-6. En outre, l'infection par les parasites PbNK65-hrfΔ est caractérisée par l’élimination du parasite conduisant à une protection durable et au développement d’une mémoire immunitaire caractérisée par une augmentation d’IL-6, une diminution de l’expression de PD-1 sur les cellules T et une amélioration de la phagocytose dépendante des anticorps, confirmant l'importance de la protéine HRF dans la virulence du parasite. HRF est le premier gène de parasite Plasmodium dont l’effet direct sur la réponse immunitaire de l’hôte est démontré. / Recent findings have raised the hypothesis that clinical susceptibility to malaria may be related to allergy-type response. In human infection with P. falciparum, as well as in murine models of malaria, increased levels of histamine have been shown to be associated with disease severity. Histamine releasing factor (HRF), shown to be implicated in the release of pro-inflammatory histamine during late-phase allergy, was demonstrated to be produced by the parasite during mild and severe malaria infections suggesting that Plasmodium HRF may affect host immune responses and contributes to the pathogenesis. The objectives of this work were to evaluate the role of Plasmodium HRF in the development of the immune response and to determine whether its expression is associated with the severity of malaria disease by studying two HRF-deficient (hrfΔ) murine parasites (PbANKA and PbNK65). Infection with PbANKA-hrfΔ sporozoites showed a decrease in the frequency of ECM due to the impairment of the development of the mutant parasites in liver stages as a consequence of the up-regulation of IL-6. Infection with PbNK65-hrfΔ parasites confirmed the importance of HRF in enhancing the virulence of the parasite. Indeed, PbNK65-hrfΔ infection results in parasite clearance leading to a long-lasting protection and immune memory as reflected by an up-regulation of IL-6, a down-regulation of PD-1 expression on T cells and in the enhancement of Ab-mediated phagocytosis. HRF is the first parasite gene which directly modulates the host immune response.
244

Contribution à la compréhension de l' "Expectation gap" en audit / A contribution to the understanding of the audit expectation gap

Jedidi, Imen 24 June 2013 (has links)
L’écart entre ce que le public attend de la part de l’auditeur et ce que ce dernier pense réaliser est connu sous le vocable d’ « expectation gap ». Cette recherche a pour ambition de contribuer à la compréhension de ce phénomène. Nous appréhendons l’ « expectation gap » dans ses dimensions discursive et normative. Ceci nous conduit à poser les deux questions de recherche suivantes : - Comment et pourquoi le concept d’ « expectation gap » a-t-il émergé dans le discours de la profession d’audit ? - Quel est le rôle des normes d’audit dans la réduction de l’ « expectation gap » ? Notre démarche méthodologique, qui s’inscrit dans le contexte français, comporte trois phases : une étude documentaire longitudinale, une enquête fondée sur des entretiens et l’étude du cas de la norme NEP 705 « Justification des appréciations ». Elle permet de montrer que le concept d’ « expectation gap » a été introduit en France dans les années 1990 sous l’impulsion d’institutions européennes et internationales. L’ « expectation gap » est utilisé dans les discours comme une excuse permettant aux auditeurs d’échapper aux accusations du public et de conserver leur statut et leur position sur le marché. De surcroît, les normes d’audit en France non seulement ne permettent pas de réduire l’ « expectation gap », mais jouent au contraire un rôle légitimant. / The « expectation gap » is defined as the gap between what the public expects from the auditor and what the auditor expects to achieve. The present research treats the expectation gap in its discursive and normative dimensions. It aims to contribute to the understanding of the expectation gap phenomenon by examining the following research questions: How and why the concept of «expectation gap» has emerged in the discourse of the audit profession? And what is the role of auditing standards in the reduction of the expectation gap? We address these questions within the French context using a methodological approach that consists of three phases: a longitudinal documentary study, a survey based on interviews, and a case study of the standard NEP 705 «Justification of assessments». We find that the concept of «expectation gap» was introduced in France in the 1990s under the influence of European and international institutions. We also find that the expectation gap is used in discourses as an excuse allowing auditors to escape public accusations and maintain their status and position in the market. Finally, we find that auditing standards in France not only don’t reduce the expectation gap, but actually play a role in legitimizing it.
245

Determinantes do tax gap do ICMS: uma análise sob a ótica dos agentes fiscais do Estado de São Paulo / Determinants of the ICMS´s tax gap: an analysis from the perspective of fiscal agents of State of São Paulo

Luís Gustavo Chiarelli de Sousa 14 June 2018 (has links)
As mudanças advindas com a popularização da tecnologia, com maior agudez no ambiente corporativo, associadas à assimetria informacional existente entre os contribuintes e as autoridades fiscais, ganharam novos contornos com a implementação do projeto SPED. Tal projeto trouxe em seu bojo a promessa de uma ferramenta com a capacidade de reduzir o tax gap, diferença entre o montante dos tributos devidos conforme a legislação e os tempestivamente recolhidos pelos contribuintes, em um ambiente saturado pela alta carga tributária e que, concomitantemente, atravessa um período de crise política e econômica. Neste cenário, os esforços das autoridades fiscais para a redução do tax gap tornam-se essenciais para que haja um maior volume arrecadatório sem que haja a criação de novos tributos. Diferentemente da maior parte dos estudos efetuados para análise do tax gap, este trabalho concentrou-se na análise de um tributo sobre o valor adicionado, o ICMS, tributo mais representativo do Produto Interno Bruto brasileiro. Nesse contexto, o objetivo deste estudo concentrou-se em avaliar como a influência das inovações técnicas e gerenciais introduzidas pelo projeto SPED impactou o tax gap do ICMS no Estado de São Paulo, sob a ótica dos agentes fiscalizadores. A partir da revisão da literatura e de sua análise exploratória foi desenvolvido o modelo teórico, testado pela técnica de modelagem de equações estruturais PLS-SEM. Os resultados mostraram que houve uma influência significativa dos determinantes do tax gap apresentados na literatura e do SPED no tax gap do ICMS paulista, com ênfase para as fiscalizações mais ágeis e abrangentes, maior acesso às informações dos contribuintes, influência na decisão do contribuinte em reduzir a parcela dos valores a sonegar e a identificação daqueles que declaram valores menores que os devidos. Os resultados contribuem para o desenvolvimento teórico do tax gap dos VATs, uma vez testadas e confirmadas a influência dos seus determinantes e do projeto SPED. / The changes coming by the popularization of technology, with greater acuteness in the corporate environment, associated with the informational asymmetry existing between taxpayers and tax authorities, have gained new contours with the implementation of the SPED project. This project brought in its wake the promise of a tool with the capacity to reduce the tax gap, the difference between the amount of taxes due according to the legislation and those that have been collected by taxpayers in an environment saturated by the high tax burden and which, at the same time, period of political and economic crisis. In this context, the efforts of the tax authorities to reduce the tax gap are essential to a higher collection volume without the creation of new taxes. Unlike most of the studies carried out to analyze the tax gap, this work focused on the analysis of a value-added tax, the ICMS, the most representative tax of the Brazilian Gross Domestic Product. In this way, the objective of this study was to understand how the determinants of the tax gap and the SPED project have helped the São Paulo government to reduce informational asymmetry with taxpayers, from the point of view of tax authorities. From the literature review and its exploratory analysis, the theoretical model was developed, tested by the structural equation modeling technique PLS-SEM. The results showed that there was a significant influence of the determinants of the tax gap presented in the literature and SPED in the ICMS´s tax gap of São Paulo, with emphasis on the more agile and comprehensive inspections, greater access to taxpayers\' information, influence on the taxpayer\'s decision to reduce the portion of the amounts to be withheld and the identification of those that declare lower amounts than those due. The results contribute to the theoretical development of the tax gap of the VATs once they have been tested and confirmed the influence of their determinants and the SPED project.
246

Surface Response to Slip Along a Propagating Blind Thrust Fault, Wheeler Ridge, California

January 2015 (has links)
abstract: Understanding topography developed above an active blind thrust fault is critical to quantifying the along-strike variability of the timing, magnitude, and rate of fault slip at depth. Hillslope and fluvial processes respond to growing topography such that the existing landscape is an indicator of constructional and destruction processes. Light detection and ranging (lidar) data provide a necessary tool for fine-scale quantitative understanding of the topography to understand the tectonic evolution of blind thrust faulting. In this thesis, lidar topographic data collected in 2014 are applied to a well-studied laterally propagating anticline developed above a blind thrust fault in order to assess the geomorphic response of along-strike variations in tectonic deformation. Wheeler Ridge is an asymmetric east-propagating anticline (10 km axis, 330 m topographic relief) above a north-vergent blind thrust fault at the northern front of the Transverse Ranges, Southern San Joaquin Valley, California. Wheeler Ridge is part of a thrust system initiating in the late Miocene and is known to have significant historic earthquakes occur (e.g., 1952 Mw 7.3 Kern County earthquake). Analysis of the lidar data enables quantitative assessment of four key geomorphic relationships that may be indicative of relative variation in local rock uplift. First, I observe remnant landforms in the youngest, easternmost section of Wheeler Ridge that indicate the erosional history of older deposits to the west. Second, I examine the central portion of Wheeler Ridge where drainages and hillslopes are closely tied to uplift rates. Third, I observe the major wind gap within which a series of knickpoints are aligned at a similar elevation and tie into the local depositional and uplift history. Finally, I survey the western section and specifically, the fold backlimb where high-resolution topography and field mapping indicate long ridgelines that may preserve the uplifted and tilted alluvial fan morphology. I address changing landforms along the fold axis to test whether backlimb interfluves are paleosurfaces or the result of post-tectonic erosional hillslope processes. This work will be paired with future geochronology to update the ages of uplifted alluvial fan deposits and better constrain the timing of along-strike uplift of Wheeler Ridge. / Dissertation/Thesis / Masters Thesis Geological Sciences 2015
247

Electron tunnelling study of high-temperature superconductors

Chandler, Simon John January 1994 (has links)
This dissertation describes work carried out between June 1987 and October 1991, in the Low Temperature Physics Group at the Cavendish Laboratory, Cambridge. The aim of this work was to use electron tunnelling spectroscopy to measure the density of excitation states of the recently discovered high-temperature superconductors. Tunnelling is the most sensitive method for measuring a superconductor’s energy gap, and historically has provided important evidence for the microscopic mechanism of superconductivity in conventional metals. It was hoped that electron tunnelling would prove equally successful in revealing the mechanism of superconductivity in these new materials. Preliminary experiments showed that a thick, degraded surface layer prevented preparation of high-quality tunnel junctions by conventional evaporation techniques. For this reason, apparatus for the formation and fine control of low-temperature point-contact junctions was constructed, together with new measurement electronics and a computer-controlled data-acquisition system. To test this apparatus, point-contact junctions were formed on conventional superconductors. By increasing pressure of the tip on the sample the junction could be moved from the tunnelling to the metallic regime. Point-contact measurements were then made on a number of ceramic, single-crystal and thin-film high-temperature superconducting materials; some not previously investigated by tunnelling. Although ‘gap-like’ structure was occasionally observed, anomalous features (e.g., voltage-dependent background, broadening, large zero-bias conductance) were always present and usually dominated the tunnelling characteristics. These complicate estimation of the energy gap and preclude measurement of more subtle properties such as gap anisotropy or the effective phonon spectrum, α2F. The origins of these non-ideal features have been much debated in the literature and are reviewed in this dissertation. In the case of thin films deposited by laser ablation the tunnelling characteristics were dominated by single-electron tunnelling effects (Coulomb gap and staircase structure). The results suggest that the surface region consists of numerous, isolated normal metal particles.
248

Dinâmica de Partículas em Estruturas Periódicas

Vieira, Marcelo da Silva 22 December 2010 (has links)
Made available in DSpace on 2015-05-14T12:14:03Z (GMT). No. of bitstreams: 1 arquivocompleto.pdf: 1077441 bytes, checksum: 7e40786e3a70b55afbfcd9bdc28c5ffa (MD5) Previous issue date: 2010-12-22 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / One of the foundations of the actual technology is the Quantum Mechanics. Through Quantum Mechanics, with the development of semiconductors physics, we are able to build devices which, manipulate particles for certain purposes. As an example of these devices, we have the diode and transistor. In this thesis we seek physical systems, to obtain some quantum effects, theorically. The quantum effects which we want to obtain, are a band structure for photons and charged particles, the Aharonov-Bohm effect for photons and geometric phases for relativistic particles described by non-Hermitian Hamiltonian. For this purpose, the issues addressed here are: the study of photons in photonic crystals formed by topological insulators, the description of systems of charged particles of varying mass, the study of dynamics of the charged particles with periodic mass, the study of the Aharonov- Bohm for the photon through a viscous uid, and the appearance of geometric phases for relativistic particles described by non hermitian Hamiltonian. The main contributions of our work was the proposal for a Hamiltonian which describes particles with variable mass, obtaining a structure of energy bands for a charged particle with periodic mass, obtaining a structure of frequency bands for photons in a photonic crystal formed by topological insulators , showing the Aharonov-Bohm effect for the photon, where the vorticity of a viscous uid is the role of magnetic fields confined, and show that relativistic particles subject to non-Hermitian Hamiltonian which varies slowly, has complex geometric phases. / A tecnologia que usamos nos dias de hoje tem como uma de suas bases principais, a Mecânica Quântica. Através da Mecânica Quântica, com o desenvolvimento da física dos semicontutores, somos capazes de construir dispositivos os quais, manipulam partículas para determinados fins. Como exemplo destes dispositivos, temos o diodo e o transistor, que são o coração da eletrônica. Nesta tese, buscamos teoricamente sistemas físicos para a obtenção de certos efeitos quânticos. Tais efeitos que desejamos obter são, uma estrutura de bandas para fótons e partículas carregadas, o efeito Aharonov-Bohm para fótons, e fases geométricas para partículas relativísticas descritas por hamiltonianos não hermitianos. Para tal finalidade, os problemas tratados aquisição: o estudo de fótons em cristais fotônicos formados por isolantes topológicos, a descrição de sistemas de partículas carregadas de massa variável, o estudo da dinâmica de partículas carregadas de massa periódica, o estudo do efeito Aharonov-Bohm para o fóton através de um fluido viscoso, e o surgimento de fases geométricas para partículas relativísiticas sujeitas a hamiltonianos não hermitianos e que variam lentamente. As principais contribuições do nosso trabalho, foram a proposta para um hamiltoniano que descreve partículas com massa variável, a obtenção de uma estrutura de bandas de energia para uma partícula carregada com massa periódicas, a obtenção de uma estrutura de bandas de frequência para fótons num cristal fotônico formado por isolantes topológicos, á obtenção de um análogo do efeito Aharonov-Bohm para o fóton, onde a vorticidade de um uido viscoso faz o papel do campo magnético confinado, e mostrar que partículas relativísticas sujeitas a hamiltonianos não hermitianos e que variam lentamentem, apresentam fases geométricas complexas.
249

O modelo de Hubbard unidimensional via DFT: o potencial de troca e correlação e o funcional híbrido / The one-dimensional Hubbard model via DFT: the exchange-correlation potential and the hybrid functional

Lucas Marcelo Cavalari Nardi 27 July 2016 (has links)
A Teoria do funcional da Densidade (DFT) é muito empregada no estudo da densidade eletrônica e energia do estado fundamental de sistemas interagente de muitos elétrons. Uma de suas desvantagens é que, apesar de formalmente exata, a DFT depende de aproximações no funcional de troca e correlação Exc[n]. Uma de suas vantagens é a possibilidade de trabalhar com a conexão adiabática, que permite conectar explicitamente o sistema interagente de interesse com uma versão não-interagente de mesma densidade. Baseado em seu escopo esta dissertação tem como objetivo tratar da DFT no modelo de Hubbard unidimensional. Uma das vantagens em trabalhar com o Hubbard é a existência de uma solução formalmente exata para a energia do modelo homogêneo e unidimensional via ansatz de Bethe, tal solução serve de base para os nossos cálculos e resultados. Outra vantagem do modelo de Hubbard é a existência de um gap que aproximações usuais na DFT falham em reproduzir. Um de nossos resultados é calcular o gap de duas formas. Uma através da derivada da solução via ansatz de Bethe e outro é tratar o Hamiltoniano pela conexão adiabática, calcular o gap pelo potencial químico, este último calculado pelo ansatz de Bethe. Ao final comparamos a precisão dos métodos, apenas para descobrir que o método via potencial químico é mais preciso. Por último usamos a conexão adiabática e a aproximação de Hartree-Fock para teorizar um funcional híbrido no modelo de Hubbard unidimensional. / The Density Functional Theory (DFT) is a widely used in the study of electronic density and energy of the ground-state of interacting systems consisting of many electrons. One of its disadvantages is that, although it is formally exact, the DFT depends on approximations of the exchange-correlation functional Exc[n]. One of its advantages consists of the possibility of working with the adiabatic connection, which allows a explicit connection between the interacting system of our interest and a non-interacting system that yields the same density. Based on its scope this dissertation aims to address the DFT in the one-dimensional Hubbard model. One of the Hubbards model advantage consists of the existence of a formally exact solution to the energy of the homogeneous one-dimensional model via Bethe ansatz, such a solution serves as the basis for our calculations and results. Anothe Hubbards model advantage is the existence of a gap that usual approximations in DFT fail to calculate. One of our results is to calculate the gap in two different ways. One through the derivative of the Bethe ansatz solution and the other is to address the Hamiltonian through the adiabatic connection, calculate the gap through the chemical potential, the latter calculated via Bethe ansatz. In the end we compare their precisions, only to find that the one via chemical potential is more precise. At last we use the adiabatic connection and the Hartree-Fock approximation to theorize a hybrid functional in the one-dimensional Hubbard model.
250

Quantificando o potencial de expansão sustentável da produção de amendoim no Estado de São Paulo / Assessing the potential for sustainable intensification of peanut production in the State of Sao Paulo - Brazil

Bruno Araújo Alves 14 March 2018 (has links)
O amendoim (Arachis hypogaea L.) é originário da América do Sul e foi amplamente disseminado pelo mundo, provavelmente por causa do seu sabor agradável e valor nutritivo. A cultura do amendoim é uma alternativa em sistema de rotação de culturas em áreas de cana-de-açúcar no momento da reforma dos canaviais, sendo esta a razão pela qual o Estado de São Paulo, principal produtor de cana, seja também o principal produtor brasileiro de amendoim. A aplicação do conceito da eficiência de produção agrícola para avaliação da cultura do amendoim pode fundamentar análises estratégicas para o setor. Uma das ferramentas usadas para este tipo de aplicação são os modelos baseados em processos. Dentre os modelos de crescimento para a cultura do amendoim já existente, destaca-se o incluído no sistema computacional DSSAT, denominado CROPGRO, que tem sido bastante aplicado em todo o mundo por pesquisadores da área. O desenvolvimento de modelos próprios por pesquisadores intensifica o processo de aprendizado e auxilia na redução de incertezas. O objetivo deste trabalho foi gerar conhecimento sobre a cultura do amendoim quanto a necessidade hídrica, conciliado ao desenvolvimento e calibração de modelos de simulação para quantificação da eficiência de produção agrícola nas principais regiões produtoras do Estado de São Paulo. A calibração do modelo CROPGRO-Peanut foi eficiente em simular a fenologia, para as variáveis vegetativas o índice d de Wilmott foi satisfatório para IAF (0,88 a 0,90), N° de folhas (0,58 a 0,85), AF específica (0,82 a 0,98), massa vegetativa (0,94 a 0,98) conforme a reposição hídrica aplicada, com valores de r2 acima de 0,65. Quanto as variáveis produtivas, embora os índices d e r2 foram satisfatórios, a EF foi baixa para ambos os tratamentos. Já o Simulador agronômico simplificado para Arachis hypogaea (SASAH), modelo inicialmente proposto neste trabalho pode ser considerando ainda em fase de construção e necessita de ajustes adicionais em seus algoritmos, não sendo utilizado na tese para simulação da produção potencial e atingível do amendoim. A eficiência média da produção no estado de São Paulo é de 52%, variando entre 33% em Ribeirão Preto até 72% em Marília. / Peanut (Arachis hypogaea L.) originates from South America and was widely disseminated throughout the world, probably because of its pleasant taste and nutritional value. The peanut crop is an alternative in a system of crop rotation in areas of sugarcane at the time of sugarcane reform, which is why the State of São Paulo, the main producer of sugarcane, is also the main producer Brazilian peanut. The application of the concept of agricultural production efficiency to evaluate the peanut crop can support strategic analysis for the sector. One of the tools used for this type of application is process-based models. Among the growth models for the existing peanut crop, the one included in the DSSAT computer system, called CROPGRO, has been widely applied by researchers in the area. The development of own models by researchers intensifies the learning process and helps reduce uncertainty. The goal of this work was to generate knowledge about the peanut crop as the water requirement, the development and calibration of simulation models to quantify the agricultural production efficiency in the main producing regions of the São Paulo State. The calibration of the CROPGRO-Peanut model was efficient in simulate the phenology, for the vegetative variables the Wilmott index was satisfactory for LAI (0.88 to 0.90), N° of leaves (0.58 to 0.85), Specific AF (0.82 to 0.98), vegetative mass (0.94 to 0.98) according to the applied water replacement, with r2 values above 0.65. Regarding the productive variables, although the indices d and r2 were satisfactory, the EF was low for both treatments. The simplified agronomic simulator for Arachis hypogaea (SASAH), a model initially proposed in this work, can be considered still in the construction phase and requires additional adjustments in its algorithms, and it is not used in the thesis to simulate the potential and attainable yield of peanuts. The average efficiency of production in the state of São Paulo is 52%, ranging from 33% in Ribeirão Preto to 72% in Marília.

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