Dissertations / Theses: 'Complexe EDA'

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Bourbon, Gautier. "Etude mécanistique des réatiοns phοtο-induites par RΜΝ, cοuplée à l'illuminatiοn in situ." Electronic Thesis or Diss., Normandie, 2024. http://www.theses.fr/2024NORMR068.

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Les recherches présentées dans ce manuscrit de thèse se divisent en deux parties. Dans la première partie, nous avons étudié la dégradation photocatalysée du N-méthoxy-N-(triméthylsilylméthyl)benzaldéhyde en présence de rose bengale dans l’acétonitrile. Les expériences de RMN 1D, la RMN 1H photo-CIDNP, ainsi que les analyses 2D 1H-13C HSQC et HMBC, combinées à une illumination in situ et ex situ, ont permis d'élucider la structure de plusieurs intermédiaires et produits formés durant cette réaction. L'illumination ex situ, réalisée à l'aide d'un système de flux continu, a été particulièrement utile pour compléter les résultats obtenus in situ et pour établir des comparaisons avec ceux obtenus par synthèse, soulignant ainsi l'importance de l'illumination ex situ dans l'étude des réactions en photochimie. Par ailleurs, les expériences de RMN 1H photo-CIDNP ont clairement démontré que la dégradation de l'éther de l’hémiaminal en présence de rose bengale passe par la formation d'un radical cation, sans engendrer de formation de 1,3-dipôle.Dans la seconde partie, nous nous sommes intéressés à la mécanistique de la réaction d’alkylation photo-induite via un complexe EDA (sel de Katritzky/DIPEA), en utilisant la RMN couplée à l’illumination in situ. Grâce aux expériences de RMN 1H photo-CIDNP, nous avons mis en évidence la présence de deux complexes EDA distincts dans le milieu réactionnel : un complexe 1:1 et un complexe 1:2 (sel de Katritzky : DIPEA), absorbant respectivement à λ = 450 nm et à λ = 520 nm. Les études de RMN 1D 1H et 1H photo-CIDNP ont révélé l'absence de diffusion du groupe partant du sel de Katritzky, prouvant ainsi que la réaction d’alkylation s'effectue dans la sphère de solvatation du complexe EDA. Ces observations, combinées aux données extraites des expériences de RMN 1H DOSY, ont permis d'identifier la nature des agrégats (complexe EDA/substrat) impliqués dans la réactivité aux deux longueurs d'onde, démontrant clairement le lien étroit entre la proportion de ces agrégats dans le milieu réactionnel et le rendement de la réaction d’alkylation photo-induite
The research presented in this thesis manuscript is organized into two main sections. The first section investigates the photocatalytic degradation of N-methoxy-N-(trimethylsilylmethyl)benzaldehyde in the presence of rose Bengal in acetonitrile. We utilized various techniques, including 1D NMR experiments, 1H photo-CIDNP, and 2D 1H-13C HSQC and HMBC analyses, alongside both in situ and ex situ illumination. These methods enabled us to elucidate the structures of several intermediates and products formed during the reaction. Notably, ex situ illumination, executed through a continuous flow system, proved particularly beneficial for complementing our in situ results and making comparisons with synthesized products, underscoring the significant role of ex situ illumination in the study of photochemical reactions. Moreover, the 1H photo-CIDNP experiments clearly indicated that the degradation of the hemiaminal ether in the presence of rose Bengal occurs via the formation of a cation radical, without the generation of any 1,3-dipole intermediates.In the second section, we shifted our focus to the mechanism of the photo-induced alkylation reaction via an EDA complex (Katritzky salt/DIPEA), employing NMR in conjunction with in situ illumination. 1H photo-CIDNP experiments revealed the presence of two distinct EDA complexes in the reaction medium: a 1:1 complex and a 1:2 complex (Katritzky salt: DIPEA), which absorb at λ = 450 nm and λ = 520 nm, respectively. Additional 1D 1H NMR and 1H photo-CIDNP studies demonstrated the absence of leaving group diffusion from the Katritzky salt, confirming that the alkylation reaction occurs within the solvation sphere of the EDA complex. These findings, along with data obtained from 1H DOSY NMR experiments, allowed us to ascertain the nature of the aggregates (EDA complex/substrate) participating in reactivity at both wavelengths. This clearly illustrates the close relationship between the proportion of these aggregates in the reaction medium and the yield of the photo-induced alkylation reaction

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Azaiez, Asma. "Les singularités en temps fini pour les équations semi-linéaires des ondes." Thesis, Paris 13, 2014. http://www.theses.fr/2014PA132046.

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Cette thèse est dédiée à l’étude du phénomène d’explosion en temps fini pour les équations semi-linéaires des ondes. On traite deux modèles dans ce travail.Dans une première direction, on considère l’équation semi-linéaire des ondes à valeurs complexes avec une nonlinéarité en puissance. On caractérise d’abord toutes les solutions du problème stationnaire comme une famille à deux paramètres.Ensuite, on utilise une approche de système dynamique pour montrer que la solution en transformation auto-similaire s’approche d’une solution stationnaire particulière dans l’espace d’énergie, dans le cas des points non caractéristiques.Ceci donne le profil à l’explosion pour l’équation originale dans le cas non-caractéristique.Dans une seconde direction, on étudie l’exemple de l’équation des ondes avec source exponentielle critique en dimension 1. On généralise les résultats de Godin pour une classe de données initiales beaucoup plus grandes. On prouve des estimations à l’explosion pour tout point de l’espace et on donne une estimation optimale du taux d’explosion pour les points non-caractéristiques
This thesis is devoted to the study of the finite time blow-up phenomena for the semilinear waves equations. We treat two models in this work.In the first part, we consider a complex-valued solution for the semilinear wave equation with power nonlinearity. We first characterize all the solutions of the associated stationary problem as a two-parameter family. Then, weuse a dynamical system formulation to show that the solution in self-similar variables approaches some particular stationary one in the energy norm, in the non-characteristic case. This gives the blow-up profile for the original equation in the non-characteristic case.The second part is dedicated to the study of the semilinear wave equation with exponential nonlinearity in one space dimension. We generalize the results of Godin to a much larger class of initial data. We prove blow-up estimates near any point and give an optimal bound on the blow-up rate near the non characteristic points

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Norén, Katarina. "Coordination Chemistry of Monocarboxylate and Aminocarboxylate Complexes at the Water/Goethite Interface." Doctoral thesis, Umeå University, Chemistry, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1337.

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This thesis is a summary of five papers with focus on adsorption processes of various monocarboxylates and aminocarboxylates at the water/goethite interface. Interaction of organic acids at the water/mineral interfaces are of importance in biogeochemical processes, since such processes have potential to alter mobility and bioavailability of the acids and metal ions.

In order to determine the coordination chemistry of acetate, benzoate, cyclohexanecarboxylate, sarcosine, MIDA (methyliminediacetic acid), EDDA (ethylenediamine-N,N’-diacetic acid) and EDTA (ethylenediamine-N,N’-tetraacetic acid) upon adsorption to the goethite (alpha-FeOOH) surface, a combination of quantitative measurements with attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) was utilized.

Over the pH range studied here (pH 3- 9) all ligands, except for sarcosine, have been found to form surface complexes with goethite. In general, theses were characterized as outer sphere surface complexes i.e. with no direct interaction with surface Fe(III) metal ions. Furthermore, two types of different outer-sphere complexes were identified, the solvent-surface hydration-separated ion pair, and hydration-shared ion pair. For the monocarboxylate surface complexes distinction between these two could be made. At high pH values the solvent-surface hydration-separated ion pair was the predominating complex, while at low pH the surface complex is stabilized through the formation of strong hydrogen bonds with the goethite surface. However, it was not possible to clearly separate between the two outer-sphere complexes for coordination of the aminocarboxylates with the surface of goethite. Additionally, EDDA also formed an inner-sphere surface complex at high pH values. The EDDA molecule was suggested to coordinate to the surface by forming a five membered ring with an iron at the goethite surface, through the amine and carboxylate groups.

Contrary to the other ligands studied, EDTA significantly induced dissolution of goethite. Some of the dissolved iron, in the form of the highly stable FeEDTA- solution complex, was indicated to re-adsorb to the mineral surface as a ternary complex. Similar ternary surface complexes were also found in the Ga(III)EDTA/goethite system, and quantitative and spectroscopic studies on adsorption of Ga(III) in presence and absence of EDTA showed that EDTA considerably effects speciation of gallium at goethite surface.

The collective results in this thesis show that the affinity of these ligands for the surface of goethite is primarily governed by their chemical composition and structure, and especially important are the types, numbers and relative position of functional groups within the molecular structure.

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Sugiharto, Eko. "Complexation de l'ion vanadyle, vo**(2+) par des ligands polycoordinantes ouverts ou macrocycliques : analogies avec l'ion vo::(2)**(+)." Université Louis Pasteur (Strasbourg) (1971-2008), 1988. http://www.theses.fr/1988STR13100.

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Platzer, Edna. "Spatial cognition research the human navigation process and its comparability in complex real and virtual environments /." [S.l.] : [s.n.], 2005. http://137.193.200.177/ediss/platzer-edna/meta.html.

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Fontana, Marcus Vinícius Liessem. "Complexidade e reconhecimento: as dinâmicas do afeto e do conflito na EAD." Universidade Federal de Santa Maria, 2015. http://repositorio.ufsm.br/handle/1/3496.

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In this thesis, I analyze how conflict and affection, as designed by the German philosopher Axel Honneth, especially in his work The Struggle for Recognition: Moral Grammar of Social Conflicts, interfere with the dynamics of a group made up of professors and pre-service teachers in e-learning. From the perspective of Complex Thought of the French sociologist Edgar Morin, I conceive the group as a complex social system. As an exploratory research, I started with the reading of the autobiographical essays wrote by the students who completed the Degree in Spanish in Federal University of Santa Maria in 2013. In those essays, I identified situations around conflicts and affective recognition experienced by the pre-service teachers, and then I selected some informants. These informants participated in narrative interviews, in which they told their respective academic trajectories. Later, I also interviewed the professors, mentioned by them in situations of affective or conflictual interaction. I analyzed all this material from the perspective of Reconstructive Hermeneutics, making the different narratives dialogue to reconstruct the situations experienced by the narrators. From this reconstruction emerges the fact that affectivity is a constant in the relations established in e-learning and we can see it as a facilitator of learning, as well as a cohesive force that tends to keep straight the complex social system. Also, emerge conflict situations. Although the conflict is not seen as something desirable, it shows potential as a maintainer of the complex social system, and it demonstrates power to stimulate new ways of thinking, to create innovative strategies of work and new dynamics of interaction between people. Innovation resulting from the conflict serves as negentropic force, which is opposed to entropy or systemic loss of energy, contributing to the longevity of this system and to obtain positive results in educational terms. I hope these findings tend to contribute to the understanding of the dynamics of relationships in e-learning, allowing its professors understand the importance of human interactions that are revealed behind the computers.
Neste trabalho, analiso de que forma o conflito e a afetividade, conforme concebidos pelo filósofo alemão Axel Honneth, sobretudo em sua obra Luta por Reconhecimento: a gramática moral dos conflitos sociais, interferem na dinâmica de um grupo constituído por professores e professores em formação na modalidade Educação a Distância. Concebo o grupo como um sistema social complexo a partir da perspectiva do Pensamento Complexo do sociólogo francês Edgar Morin. Como fonte de dados, debruço-me, inicialmente, sobre os trabalhos de conclusão de curso, inseridos no gênero memorial de formação, dos alunos que concluíram o Curso de Licenciatura em Espanhol e Literaturas EaD da Universidade Federal de Santa Maria em 2013. A partir de uma pesquisa exploratória, em que foram identificados memoriais narrando situações de conflito e de reconhecimento afetivo vividas pelos professores em formação, selecionei alguns informantes. Esses informantes participaram, então, de entrevistas narrativas, em que contaram suas respectivas trajetórias acadêmicas. Mais tarde, os professores por eles mencionados em situações de interação afetiva ou conflitiva foram também entrevistados. Todo esse material foi analisado a partir da perspectiva da Hermenêutica Reconstrutiva, fazendo dialogar as diferentes narrativas a fim de reconstituir as situações vividas pelos narradores. Dessa reconstrução emerge o fato de que a afetividade é uma constante nas relações estabelecidas em EaD e se mostra como elemento facilitador da aprendizagem, além de uma força de coesão que tende a manter o sistema complexo social em boa marcha. Emergem, também, as situações de conflito. Apesar de o conflito não ser encarado como algo desejável, demonstro seu papel como potencial mantenedor do sistema social complexo, pois tem o poder de estimular novas maneiras de pensar, a criação de estratégias inovadoras de trabalho e de novas dinâmicas de interação entre as pessoas. A inovação decorrente do conflito funciona como força neguentrópica, que se contrapõe à entropia ou perda de energia sistêmica, contribuindo para a longevidade desse sistema e para a obtenção de resultados positivos em termos pedagógicos. Essas conclusões tendem a contribuir com a compreensão sobre as dinâmicas das relações na Educação a Distância, permitindo aos seus professores uma percepção maior sobre a importância das interações humanas que se descortinam por detrás dos computadores.

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Carvalho, Jaqueline Bonfim de. "Equações estruturais aplicadas ao entendimento da dinâmica do carbono do solo em sistemas agroflorestais no cerrado brasileiro /." Ilha Solteira, 2019. http://hdl.handle.net/11449/191122.

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Orientador: Alan Rodrigo Panosso
Resumo: O bioma Cerrado tem sofrido modificações nas últimas décadas, perdendo parte de sua cobertura original para culturas anuais, pastagens e florestas plantadas, tendo diferentes usos da terra. Neste trabalho, foram estudadas as interações entre os diferentes usos da terra em áreas do bioma Cerrado, bem como da dinâmica de carbono no solo e os fatores latentes formados pelos atributos físicos e químicos do solo, por meio de modelos de análise de equações estruturais, com auxílio das técnicas estatísticas multivariadas. Ensaios experimentais foram conduzidos na Fazenda de Ensino, Pesquisa e Extensão (FEPE/UNESP), localizada em Selvíria-MS: Floresta plantada de Eucalipto - Eucalyptus camaldulensis (EU); Floresta plantada de Pinus - Pinus caribaea var. hondurensis (PI); Sistema silvipastoril (SI) com uma área contendo floresta plantada de Aroeira (Myracrodruon urundeuva) e capim Braquiária (Brachiaria decumbens, e Mata Nativa (MN). Foi estudado os efeitos dos atributos físicos: densidade do solo (Ds), macroporosidade (Ma), microporosidade (Mi) e químicos com ênfase especial nas propriedades relacionadas à dinâmica do carbono no solo: matéria orgânica do solo (MO), estoque de carbono do solo (EstC), estoque de nitrogênio do solo (EstN), relação carbono e nitrogênio (C/N) e o grau de humificação da matéria orgânica do solo (HLIFS). A emissão de CO2 do solo (FCO2), umidade e temperatura do solo foram avaliados nas áreas durante três períodos distintos (definidos a partir do regime hídr... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The Cerrado biome has undergone modifications in recent decades, losing part of its original cover to annual crops, pastures and planted forests, having different land uses. In this work, the interactions between the different land uses in areas of the Cerrado biome, as well as the soil carbon dynamics and the latent factors formed by the physical and chemical attributes of the soil through structural equation analysis models were studied. with the aid of multivariate statistical techniques. Experimental tests were performed at the Teaching, Research and Extension Farm (FEPE / UNESP), located in Selvíria-MS: Eucalyptus planted forest Eucalyptus camaldulensis (EU); Planted Pine Forest - Pinus caribaea var. hondurensis (PI); Silvipastoral system (SI) with an area containing Aroeira (Myracrodruon urundeuva) and native grass (Brachiaria decumbens), and Mata Nativa (MN). The effects of physical attributes: soil density (Ds), macroporosity (Ma), microporosity (Mi) and chemicals attributes were studied with special emphasis on properties related to soil carbon dynamics: soil organic matter (MO), soil carbon stock (EstC), soil nitrogen stock (EstN), carbon and nitrogen ratio (C / N), and the degree of soil organic matter (HLIFS). Soil CO2 emission (FCO2), soil moisture and temperature were evaluated in the areas during three distinct periods (defined from the water regime observed in the areas) called P1, P2 and P3, season rainfall, drought and transition, respectively, between March... (Complete abstract click electronic access below)
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Ongoue, Jean-Claude. "Les petites et moyennes entreprises autour des complexes industriels à Edea (Cameroun)." Bordeaux 1, 1994. http://www.theses.fr/1994BOR1A001.

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Berhane, Sarah. "The effect of Adenovirus E1A on the human immunoproteasome and MHC complex." Thesis, University of Birmingham, 2012. http://etheses.bham.ac.uk//id/eprint/3369/.

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Adenovirus E1A (AdE1A) is a viral oncoprotein that targets many cellular proteins and pathways, mainly those involved in transcriptional regulation. Proteasomes represent the major non-lysosomal mechanism responsible for protein degradation. Following interferon-γ treatment, three proteasome subunits are replaced by immunosubunits LMP2, LMP7 and MECL-1 producing immunoproteasomes. The proteasome and immunoproteasome generate peptide antigens for MHC class I presentation to cytotoxic T-cells. In this study, the effect of AdE1A on human immunoproteasomes as well as MHC class I and class II cell surface expression was examined. It was found that AdE1A interacts with the immunoproteasome subunit MECL-1 through its N-terminal and CR3 regions. AdE1A also down-regulated all three immunosubunit expressions during adenovirus infection, transformation and AdE1A transfection, with the exception of Ad5-transformed cells where immunosubunit expression remained unchanged. Furthermore, MHC class I expression remained unaffected in the same three backgrounds. However, in the Ad12 transformants MHC class I was generally reduced prior to IFNγ treatment but was expressed after. MHC class II surface expression, in contrast, was down-regulated in all cases, except in Ad5 infected cells. Similarly, AdE1A reduced IFNγ-stimulated STAT1 phosphorylation and transcriptional response to IFNγ. And finally, T-cell recognition of target cells was reduced in the presence of AdE1A. In conclusion, AdE1A targets the human immunoproteasome, both through direct binding and down-regulation of expression. It also targets the expression of MHC class I and class II surface expression.

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Thirouin, Joseph. "Instabilité et croissance des normes de Sobolev pour certaines EDP hamiltoniennes." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS195/document.

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Cette thèse est consacrée à l'étude de solutions globales et régulières de certaines EDP hamiltoniennes, du point de vue de la croissance de leurs normes de Sobolev. Un tel phénomène traduit une modification de la répartition de l'énergie dans l'espace des fréquences, appelée parfois "turbulence faible". On étudie d'abord une équation d'évolution non-linéaire où intervient un laplacien fractionnaire, et l'on prouve des estimées a priori sur la vitesse de croissance des normes de Sobolev. On introduit ensuite une équation où de telles estimées sont optimales : une équation de Szegő, intégrable, avec une non-linéarité quadratique, et où certaines solutions régulières croissent à vitesse exponentielle tout en restant bornées dans l'espace d'énergie. On classifie les ondes progressives de cette équation de Szegő quadratique, et l'on met en évidence l'instabilité d'une partie d'entre elles. Enfin, on exhibe pour cette équation une hiérarchie de lois de conservation, qui permet d'étudier plus précisément les solutions rationnelles turbulentes
In this thesis we study global smooth solutions of certain Hamiltonian PDEs, in order to capture the possible growth of their Sobolev norms. Such a phenomenon is typical for what is sometimes called "weak turbulence" : a change in the distribution of energy between Fourier modes. We first study a nonlinear evolution equation involving a fractional Laplacian, and we prove a priori estimates on the growth of Sobolev norms. We then introduce an equation where these estimates turn out to be optimal : an integrable Szegő equation with a quadratic nonlinearity, which admits exponentially growing smooth solutions that remain bounded in the energy space. We classify the traveling wave solutions of this quadratic Szegő equation, and show that some of them are unstable. Eventually we find a hierarchy of conservation laws for this equation, which leads us into a deeper study of rational turbulent solutions

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Menezes, Sean Christopher. "Examining the effect of CBP on the E2A-PBX1 and HOXB4 interaction." Thesis, Kingston, Ont. : [s.n.], 2008. http://hdl.handle.net/1974/1534.

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Ferracuti, Francesco. "Modeling and Diagnosis of Complex Systems Dynamics by Data-Driven Approaches." Doctoral thesis, Università Politecnica delle Marche, 2014. http://hdl.handle.net/11566/242862.

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I sistemi complessi possono essere rinvenuti in quasi tutti i campi della scienza contemporanea, e possono avere diversa natura: finanziaria, fisica, biologica, informativa, sociale, ecc. I sistemi complessi consistono di un gran numero di componenti che interagiscono non linearmente tra loro e che mostrano un comportamento collettivo non derivante semplicemente dal comportamento delle parti individuali. Sebbene tali sistemi godano di numerose proprietà, le più importanti sono: dimensionalità, incertezza, non linearità e accoppiamento tra i componenti. Le procedure per ottenere modelli analitici di determinati sistemi sono solitamente classificate in modellazione fisica e identificazione. Queste procedure possono essere difficilmente implementabili se applicate a sistemi complessi perché le loro caratteristiche peculiari rendono difficile la modellazione. Poiché un modello matematico è una descrizione del comportamento di un sistema, una modellazione accurata per i sistemi complessi è molto difficile da ottenere in pratica. Per di più, a volte, potrebbe addirittura essere impossibile descrivere il sistema attraverso equazioni analitiche. Alla luce di quanto emerso, la presente trattazione si propone di affrontare due problemi riguardanti la modellazione e la diagnosi dei sistemi complessi: il primo riguarda specificamente la modellazione di un sistema complesso, nel caso in cui il modello analitico non sia ottenibile; il secondo si riferisce alla diagnosi del comportamento del sistema. Quest’ultima attività dovrebbe rilevare se il sistema complesso è normale o se sta avvenendo un cambiamento dovuto a eventi anomali, nonché le cause probabili di tali eventi. La modellazione dei sistemi complessi viene affrontata sviluppando metodi data-driven, che sono capaci di apprendere le dinamiche del sistema complesso direttamente dai dati forniti da sensori installati sul sistema, al fine di monitorarne le variabili fisiche. La diagnosi dei sistemi complessi viene invece affrontata sviluppando metodi di apprendimento automatico in modo da classificare le probabili cause di scostamento da eventi normali del sistema. Nella trattazione ampia attenzione è posta al problema di modellazione e diagnosi di sistemi complessi con riferimento a sistemi reali, presentando diverse applicazioni pratiche e casi di studio. Il primo caso di studio riguarda la modellazione e diagnosi di difetti e guasti di motori elettrici in uno scenario di controllo qualità mentre il secondo si riferisce ad un sistema complesso indusxiii triale, quale quello di una cartiera. Nel terzo caso viene affrontata la questione di stimare la vita utile rimasta di un motore turbofan e l’ultimo tratta il problema di modellare segnali elettroencefalografici attraverso algoritmi basati sui dati. Dato che il problema di modellazione e diagnosi è affrontato attraverso procedure basate sui dati, gli algoritmi sviluppati possono essere applicati ad un’ampia classe di macchine elettriche rotanti e sistemi complessi industriali, e non solo a quelli riportati.
Complex systems are found in almost all field of contemporary science, and are associated with a wide variety of financial, physical, biological, information and social systems. Complex systems consist of a large number of nonlinearly interacting components which display collective behaviour that does not follow trivially from the behaviours of the individual parts. Although complex systems have many different properties, the most important are: dimensionality, uncertainty, nonlinearity and coupling between components. The procedures to obtain analytical models are usually classified into physical modeling and identification. These procedures cannot be implemented easily if applied to complex systems because the properties, which arise from these systems, make difficult the modeling. Since a mathematical model is a description of system behaviour, accurate modeling for a complex system is very difficult to achieve in practice. Furthermore, sometimes, it may even be impossible to describe the system by analytical equations. The present dissertation tries to address two issues regarding the modeling and diagnosis of complex systems. The first one deals with the issue of modeling a complex system, in the case the analytical model is not obtainable. The second one deals with the issue of diagnosing the system behaviour. Diagnosis should detect if the complex system is normal or a change is occurring due to abnormal events and in addition, the probable causes of the abnormal events should be detected by means of the diagnosis. Modeling of complex systems is addressed developing data-driven procedures, which are able to learn the complex system dynamics from data that are provided by installed sensors on the system in order to monitor the physical system variables. Diagnosis of complex systems is addressed developing machine learning procedures in order to classify the probable causes of deviations from system normal events. A large amount of attention is paid to the issue of modeling and diagnosis for complex systems with particular attention to real systems, for this different applications are discussed as many case studies. The first application deals with the issue of modeling and diagnose the defects and faults in a Quality Control scenario for electric motors. The second application deals with the issue of modeling and diagnose a complex industrial system as a paper mill plant. The third application deals with the issue of estimating the residual useful life of a turbofan engine and the last deals with the issue of modeling the Electroencephalography signals by data-driven algorithms in order to diagnose the user intentions. This solution addresses the modeling problem in the Brain Computer Interface context. Since the modeling and diagnosis problem is faced by data-driven procedures, the developed algorithms can be applied to a wide class of rotating electrical machines and complex industrial systems, and not only to those mentioned.

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Corrêa, Ygor. "O agir linguageiro na perspectiva dos sistemas adaptativos complexos em ambiente virtual de aprendizagem em EAD." Universidade do Vale do Rio dos Sinos, 2014. http://www.repositorio.jesuita.org.br/handle/UNISINOS/3850.

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UNISINOS - Universidade do Vale do Rio dos Sinos
O presente estudo concebe o papel central da língua no desenvolvimento humano por meio de um agir linguageiro. Nessa perspectiva, compreende-se que a linguagem se situa em práticas interacionais e está em permanente transformação. Este estudo tem caráter empírico de cunho qualitativo, inserido na plataforma Moodle, investigando a especificidade das interações realizadas em Chats, em uma disciplina de Ensino à Distância (EAD) na perspectiva da Teoria da Complexidade (GLEICK, 1994; JOHNSON 2003; LARSENFREEMAN 1997, 2008, 2009; MORIN 2008) e do Interacionismo Sociodiscursivo - ISD (BRONCKART, 1999, 2008). A compreensão epistemológica deste estudo abarca o agir humano em desenvolvimento caracterizado como um sistema adaptativo complexo. Sendo que, a partir das práticas de nível mais baixo, mas não menos complexas, os comportamentos acabam por emergir. Assim, os interagentes desenvolvem comportamentos observáveis que emergem das condições iniciais, encaminhando-se às manifestações de auto-organização. O agir humano situado na plataforma, assim como as práticas situadas por meio de tipos específicos de discursos (BRONCKART, 1999) estão entendidos como geradores de movimentos de complexidade. As relações discursivas tecnologicamente situadas foram observadas quanto à forma como os interagentes se adaptavam ao contexto discursivo. A partir das interações analisadas, elencaram-se, então, tipos de discurso e foram propostos quatro tipos de Movimentos de Complexidade que emergiram das interações discursivas: Movimento 1 – Dinamicidade discursiva entre interagentes; Movimento 2 – Não-linearidade interacional; Movimento 3 – Adaptação de agentividade (espaço-tempo) e Movimento 4 – Comportamento emergente. A análise do agir linguageiro, situado por meio de tipos de discurso identificados, apresentou baixo índice de variação da escrita em linguagem formal; como era de se esperar, dado o caráter formal da troca entre pares. O estudo permitiu evidenciar que os tipos de discurso se adaptam na medida em que os interagentes passam por mudanças interacionais de fases co-construídas em processo, alternando entre os tipos de discurso relato interativo e relato misto interativo-teórico pela ausência do discurso teórico.
This study conceives the central role of language in the human development through language acting. In this perspective, it is comprehended that language is situated in interactional practices and it is permanently transformed. This study has an empirical character and a qualitative approach, inserted in the Moodle platform, investigating the specificity of the interactions made in Chats in a Distance Learning Environment according to the Complexity Theory perspective (GLEICK, 1989; JOHNSON 2003; LARSEN-FREEMAN 1997, 2008, 2009; MORIN 2008) and the Sociodiscursive Interactionism perspective (BRONCKART, 1999, 2008). The epistemological comprehension of this study considers that the language acting under development is characterized as a complex adaptive system, in which behaviors eventually emerge from practices of lower level, but not less complex. Then, the interactants develop observing behaviors that emerge from the initial conditions, heading towards self-organization manifestations. The situated language acting on the platform, as well as the situated practices through specific types of discourse (BRONCKART, 2008), are understood as generators of complexity movements. The ways interactants adapted themselves to the discursive context were observed as discursive relations technologically situated. From the analyzed interactions, types of discourse were established and four types of complexity movements, which emerged from the discursive interactions, were proposed: Movement 1 – Discursive Dynamics among interactants; Movement 2 – Non-Interactional linearity; Movement 3 – Agentivity Adaptation (space-time); Movement 4 – Emergent Behavior. The analysis of the situated language acting, through identified types of discourse, presented a low rate of variation in formal language use, as it was expected, due to the formal character of the exchange among pairs. The study allowed us to evidence that the types of discourse are adaptable as the interactants go through phases of interactional change coconstructed in process, alternating between interactive-reporting and mixed theoreticalinteractive types of discourse, by the absence of theoretical discourse.

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14

Gati, Yousra. "Analyse mathématique et simulations numériques d'un modèle de fluides complexes." Phd thesis, Ecole des Ponts ParisTech, 2004. http://pastel.archives-ouvertes.fr/pastel-00000883.

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Nous nous intéressons à l'analyse mathématique et aux simulations numériques d'un modèle de fluides non newtoniens. Nous couplons le modèle d'Hébraud et Lequeux décrivant l'écoulement de Couette, plan de suspensions concentrés à l'échelle mésoscopique avec l'équation de conservation de la quantité de mouvement. Outre le couplage multi-échelle, la difficulté principale de ce modèle vient du fait que l'équation mésoscopique est une équation parabolique de type Fokker-Planck non linéaire qui peut dégénérer en une équation hyperbolique. Le but de cette thèse est d'étudier des deux points de vue théorique et numérique le modèle obtenu. Ainsi, dans la première partie, nous démontrons les théorèmes d'existence et d'unicité de solutions dans des espaces fonctionnels appropriés, et dans la seconde partie, nous développons des schémas numériques pour approcher les solutions du problème. Deux méthodes (déterministe et stochastique) ont été implémentées. Des tests de réduction de variance relatifs à la méthode stochastique ont été réalisés. Finalement, le problème de calibrage des paramètres par la méthode de l'adjoint a été abordé.

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15

Benavides, Mario. "Microspherule Protein Msp58 and Ubiquitin Ligase EDD Form a Stable Complex that Regulates Cell Proliferation." Thesis, City University of New York, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3561768.

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A complex molecular network is put into place at specific phases of the cell cycle to prevent unscheduled cell division that could result in malignant cell growth. Emerging evidence shows that still uncharacterized proteins play crucial functions at those cell cycle transition points. Nuclear protein Msp58 and EDD E3 ubiquitin ligase have been implicated in different aspects of cell proliferation and reported to be abnormally expressed in numerous types of cancers. The molecular mechanisms underlying Msp58 and EDD functions, however, are not well understood. The work presented here shows that Msp58 and EDD form a stable protein complex that regulates cell viability and proliferation. Interestingly, knockdown of EDD by RNA interference leads to a significant accumulation of Msp58 protein, which suggests that EDD serves as a negative regulator of Msp58. In addition, our in vivo ubiquitination assays and analyses of various cell lines treated with translational and proteasomal inhibitors demonstrate that Msp58 is regulated post-translationally by the ubiquitin-proteasome pathway. These results imply that EDD ligase activity is involved in this regulatory process. Using flow cytometry analyses and biochemical characterization of Msp58 and/or EDD depleted cells, we show that the Msp58-EDD complex plays important roles in cell cycle progression via the control of cyclin gene expression. In particular, silencing Msp58 and/or EDD alters the protein levels of cyclins B, D and E. Taken together, our data suggest that a set of the biological roles attributed to Msp58 and EDD may be executed in the context of the complex that they form, thereby revealing a novel molecular mechanism for these two proteins to accomplish their functions.

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Yarker, Joanne L. "Chromatin architecture and transcriptional regulation at the Epidermal Differentiation Complex (EDC) locus. The role of epigenetic factors in modulating chromatin structure and tissue-specific gene expression at the murine EDC locus during epidermal differentiation." Thesis, University of Bradford, 2014. http://hdl.handle.net/10454/7267.

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The epidermal differentiation complex (EDC) encodes co-ordinately regulated genes critically involved in epidermal differentiation, however knowledge of the molecular mechanisms involved in co-ordinating EDC gene expression is limited. Recent findings indicate p63 dependent changes in the nuclear localisation and higher-order chromatin folding the EDC coincide with the onset of epidermal stratification during embryonic development. Here it is demonstrated that a direct transcription target of p63, the chromatin-remodelling enzyme Brg1, modulates the specific nuclear positioning of the EDC and transcription of differentiation-specific gene encoded at the EDC. In addition, the results of high-resolution 5C-based analyses of the spatial chromatin interactome at a 5.3Mb region spanning the murine EDC in epidermal keratinocytes, and the silenced EDC in thymocytes, are presented. Chromatin interactions at the EDC region in keratinocytes include long-range interactions between multiple proximal and distal candidate gene regulatory regions. Many candidate regulatory elements involved in looping chromatin interactions at the EDC region are enriched for both active (H3K4me1, H3K27ac) and repressive (H3K27me3) chromatin marks and are bound by Sin3a and RBP2 co-repressor complexes. The chromatin interactome at the EDC in epidermal progenitor cells is enriched for bound chromatin architectural proteins Satb1, Satb2, and the cohesin subunit Rad21. Further, a substantial degree of co-localisation is observed between these chromatin architectural proteins, transcription factors and co-factors. Findings presented here suggest that a functional chromatin interactome, mediated by Satb proteins and cohesin, acts in conjunction with transcriptional repressor complexes to facilitate co-ordinated gene expression at the EDC in epidermal progenitor cells upon differentiation. These results provide a foundation for further study of the mechanisms controlling EDC gene expression in health and disease.

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Yarker, Joanne Lauren. "Chromatin architecture and transcriptional regulation at the Epidermal Differentiation Complex (EDC) locus : the role of epigenetic factors in modulating chromatin structure and tissue-specific gene expression at the murine EDC locus during epidermal differentiation." Thesis, University of Bradford, 2014. http://hdl.handle.net/10454/7267.

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The epidermal differentiation complex (EDC) encodes co-ordinately regulated genes critically involved in epidermal differentiation, however knowledge of the molecular mechanisms involved in co-ordinating EDC gene expression is limited. Recent findings indicate p63 dependent changes in the nuclear localisation and higher-order chromatin folding the EDC coincide with the onset of epidermal stratification during embryonic development. Here it is demonstrated that a direct transcription target of p63, the chromatin-remodelling enzyme Brg1, modulates the specific nuclear positioning of the EDC and transcription of differentiation-specific gene encoded at the EDC. In addition, the results of high-resolution 5C-based analyses of the spatial chromatin interactome at a 5.3Mb region spanning the murine EDC in epidermal keratinocytes, and the silenced EDC in thymocytes, are presented. Chromatin interactions at the EDC region in keratinocytes include long-range interactions between multiple proximal and distal candidate gene regulatory regions. Many candidate regulatory elements involved in looping chromatin interactions at the EDC region are enriched for both active (H3K4me1, H3K27ac) and repressive (H3K27me3) chromatin marks and are bound by Sin3a and RBP2 co-repressor complexes. The chromatin interactome at the EDC in epidermal progenitor cells is enriched for bound chromatin architectural proteins Satb1, Satb2, and the cohesin subunit Rad21. Further, a substantial degree of co-localisation is observed between these chromatin architectural proteins, transcription factors and co-factors. Findings presented here suggest that a functional chromatin interactome, mediated by Satb proteins and cohesin, acts in conjunction with transcriptional repressor complexes to facilitate co-ordinated gene expression at the EDC in epidermal progenitor cells upon differentiation. These results provide a foundation for further study of the mechanisms controlling EDC gene expression in health and disease.

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McAllister, Donald P. "Shearing Mechanisms and Complex Particle Growth in Nickel Superalloy 718." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1461079188.

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19

Sparrman, Victoria. "Tube-tap or Earliest Due Date : What happens when all jobs cannot be completed?" Thesis, Umeå universitet, Institutionen för datavetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-184627.

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In this thesis the scheduling algorithms Earliest Due Date (EDD) and Tube-tap were compared to each other. They were compared to see which algorithm generated more net profit. They were compared to each other in four different scenarios. In each scenario there were two different machines and five different jobs. Each machine had a cost and a processing rate, and each job had a length, a deadline, and a profit. In every scenario all jobs could not be completed before their deadline. The net profit was calculated by subtracting the gross profit by the machine cost. The results for the Tube-tap and EDD algorithms were almost the same for both algorithms in the different scenarios. There was one scenario where Tube-tap gained 0.5 more in profit. This was because Tube-tap had 0.5 in machine cost for one of the scenarios. The conclusions was that there should be more experimentation to see how more profitable Tube-tap can be. Specifically, there should be testing on scenarios where all jobs cannot be completed before their deadlines, but the number of operations does not exceed the available space before the last deadline.

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Bouchaud, Grégory. "Caractérisation structurale et fonctionnelle du complexe formé entre la chaîne Alpha soluble du Récepteur de l'Interleukine 15 Humaine et l'Interleukine-15 : implication en immuno-cancérologie." Nantes, 2009. https://archive.bu.univ-nantes.fr/pollux/show/show?id=73b03bed-e0da-4f75-a33c-58e52cdf2a1b.

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L'Interleukine-15 (IL-15) est une cytokine qui présente des activités semblables à celles de l'IL-2 in vitro du fait de l'utilisation commune des chaînes réceptrices IL-2Rβ et γc, la spécificité d'action étant conférée par une chaîne réceptrice α. L'IL-15Rα existe sous forme soluble après clivage protéolytique de la forme membranaire. Dans cette étude, nous avons caractérisé les mécanismes moléculaires régulant les activités agonistes et antagonistes des formes solubles de la chaîne IL-15Rα. Nous avons mis en évidence que le domaine du sIL-15Rα codée par l’exon 3 et, située à l'extrémité C-terminale du domaine sushi liant la cytokine, participe à la forte affinité du complexe IL-15/sIL-15Rα et est indispensable à la fonction antagoniste du récepteur soluble. Nous avons également montré le rôle primordial du complexe IL-15/sIL-15Rα dans des pathologies cancéreuses et inflammatoires grâces au pouvoir pro-inflammatoire induit par le sIL-15Rα dans les cancers de la tête et du cou et son implication dans la réponse thérapeutique à l'infliximab (anti-TNF) dans la maladie de Crohn. Ce travail montre que le sIL-15Rα est une composante importante dans la régulation des activités de l'IL-15 et pourrait conduire à différentes applications thérapeutiques
The Interleukin-15 (IL-15) is a cytokine which outlines similar activities as those of IL-2 in vitro because of the common use of IL-2Rβ and γc chains. The specificity of action is conferred by a private α chain (IL-15Rα). The α chain exists in soluble form after proteolytic cleavage of the membrane anchored IL-15Rα. In this study, we characterized the molecular mechanisms regulating the agonistic and antagonistic activities of the soluble forms of IL-15Rα (sIL-15Rα). We highlighted that the exon 3 encoded domain of the sIL-15Rα, located at the C-terminal end of the IL-15 binding domain (sushi) which participates to the high affinity of the IL-15/sIL-15Rα complex and is necessary for the antagonistic function of the soluble receptor. We also showed the vital role of this complex in cancer and inflammatory diseases through the capacity to escape to immunity of tumor with sIL-15Rα in head and neck cancers and it involvement in the therapeutic response to infliximab in Crohn disease. This work shows that the sIL-15Rα is an important component in the regulation of IL-15 and could lead to different therapeutic applications

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21

Alfaris, Anas (Anas Faris). "The Evolutionary Design Model (EDM) for the design of complex engineered systems : Masdar City as a case study." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/58187.

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Thesis (S.M.)--Massachusetts Institute of Technology, Computation for Design and Optimization Program, 2009.
"September 2009." Cataloged from PDF version of thesis.
Includes bibliographical references (p. 150-157).
This thesis develops a framework for constructing an Evolutionary Design Model (EDM) that would enhance the design of complex systems through an efficient process. The framework proposed is generic and suggests a group of systematic methodologies that eventually lead to a fully realized and integrated design model. Within this model, complexities of the design are handled and the uncertainties of the design evolution are managed. Using the framework, vast design spaces can be searched while solutions are intelligently modified, their performance evaluated, and their results aggregated into a compatible set for design decisions. The EDM is composed of several design states as well as design evolving processes. A design state describes a design at a particular point in time and maps the system's object to the system's requirements and identifies its relation to the context in which the system will operate. A design evolving process involves many sub-processes which include formulation, decomposition, modeling, and integration. These sub-processes are not always carried out in a sequential manner, but rather a continuous move back and forth to previous and subsequent stages is expected. The resulting design model is described as an evolutionary model that moves a system's design from simple abstract states to more complex and detailed states throughout its evolution.
(cont.) The framework utilizes system modeling methodologies that include both logical and mathematical modeling methods. The type of model used within the EDM's evolving processes is highly dependent on and driven by design needs of each process. As the design progresses a shift from logical models to mathematical models occurs within the EDM. Finally, a partial EDM is implemented within the context of a computational design system for Masdar city to demonstrate the application of the proposed framework.
By Anas Alfaris.
S.M.

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22

Benchichah, López Noor Yasmina. "La tercera edad dorada de la televisión. Battlestar Galactica y las nuevas formas de pensar, hacer y consumir el drama televisivo norteamericano." Doctoral thesis, Universitat Ramon Llull, 2015. http://hdl.handle.net/10803/285053.

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Aquesta investigació examina el succeit al panorama de les producciones televisives de ficció nortamericanes nascudes al nou segle a través de l’anàlisi en profunditat de l’estat de la ficció actual i l’aplicació d’aquest model a una serie de ciència-ficció paradigmàtica del moment, Battlestar Galactica. Així, intentarem demostrar que existeixen noves formes de pensar, fer i consumir el drama, que el criteri de qualitat ha quedat diluit en el context actual fent necessària una nova aproximació a aquest i que Battlestar Galactica és un producte singular de l’època que ha permès incloure els gèneres marginals als nous discursos de qualitat, per finalment poder legitimar l’existència de la Tercera Edat Daurada de la Televisió.
La presente investigación examina lo ocurrido en el panorama de las producciones televisivas de ficción norteamericanas nacidas en el nuevo siglo a través del análisis en profundidad del estado de la ficción actual y la aplicación de dicho modelo a una serie de ciencia-ficción paradigmática de la época, Battlestar Galactica. Así, intentaremos demostrar que existen nuevas formas de pensar, hacer y consumir el drama, que el criterio de calidad ha quedado diluido en el contexto actual haciendo necesaria una nueva aproximación a éste y que Battlestar Galactica es un producto singular de la época que ha permitido incluir los géneros marginales en los nuevos discursos de calidad, para finalmente poder legitimar la existencia de la Tercera Edad Dorada de la Televisión.
This research examines the changes in the landscape of American fiction television productions born in the new century through the in-depth analysis of the current state of the new drama model and by applying this model to a paradigmatic science-fiction series of the time, Battlestar Galactica. Thus, we will try to demonstrate that there are new ways of thinking, making and consuming the television series, that the quality concept has been diluted by a wide and unifying new approach, and that Battestar Galactica is a unique product of its time that has allowed to bring marginal television genres to the new quality discourses, to finally legitimize the existence of the Third Golden Age of Television.

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23

Antonin, Vanessa da Silva. "Degradação do complexo EDTA-Cu(II) por processos eletroquímicos oxidativos avançados." reponame:Repositório Institucional da UFABC, 2012.

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24

Cissé, Papa Alioune. "Simulation à base d'agents de la propagation de la Schistosomiase : une approche de composition et de déploiement de modèles." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066567/document.

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Nos travaux de thèse portent sur la modélisation et la simulation à base d'agents de systèmes complexes, appliquées au phénomène de propagation de la Schistosomose. Plus particulièrement, nous nous sommes intéressés aux aspects spatiaux et sociaux de la propagation de cette maladie, en utilisant une approche de couplage de modèles à base d'agents. En effet, nous avons initialement étudié la modélisation mathématique de la Schistosomose et la complexité du phénomène de sa propagation. Ce qui nous a permis d'identifier deux dynamiques épidémiologiques (dynamiques spatiale et sociale) sous-jacentes à la propagation de la Schistosomose pour lesquelles, les modèles mathématiques présentent des limites. Cette problématique nous a poussés à étudier isolément ces deux dynamiques et à proposer un modèle multi-agents pour chacune d'elles. Ces deux modèles à base d'agents, représentant deux dynamiques complémentaires d'un même système, ont été implémentés selon des formalismes et des plateformes différentes : un modèle dans GAMA, une plateforme de simulation à base d'agents ; et un autre dans JASON, une plateforme de programmation d'agents BDI (Belief, Desire, Intention). Le modèle GAMA implémente l'aspect comportemental (pour la dynamique spatiale) qui se penche sur la réactivité des individus face à l'environnement physique et le suivi de l'infection. Le modèle JASON implémente l'aspect décisionnel (pour la dynamique sociale) qui introduit la dimension cognitive et mentale des individus en assurant leur capacité de décision et de sélection qui sont déterminées par leur environnement social, culturel, économique, etc. Pour assurer la composition des deux modèles, nous avons proposé une solution de couplage (par Co-simulations) des deux plateformes GAMA et JASON. Nous avons finalement expérimenté le modèle avec un cas de dynamique de propagation de la maladie à Niamey (au Niger) pour lequel les données étaient accessibles
Our thesis work focuses on agent-based modeling and simulation of complex systems, applied to the spread of schistosomiasis. Specially, we were interested in the spatial and social aspects of the spread of the disease, using an agent-based coupling approach of models.Indeed, we initially studied the mathematical modeling of schistosomiasis and the complexity of its propagation, which allowed us to identify two epidemiological dynamics (spatial and social dynamics) underlying the spread of schistosomiasis for which mathematical models have limits. This problematic led us to study separately these two dynamics and propose an agent-based model for each. These two agent-based models, representing two complementary dynamics of a system, were implemented according different formalisms and different platforms: one model on GAMA (an agent-based simulation platform); and another on JASON (a programming platform of BDI agents). The GAMA model implements the behavioral aspect (for the spatial dynamic) that focuses on individuals reactivity with regards to the physical environment, and the monitoring of the infection. The JASON model implements the decisional aspect (for the social dynamic) that introduces the cognitive and mental dimension of individuals, ensuring their decision and selection capacities which are determined by their social, cultural and economic environment. To ensure the composition of the two models, we proposed an agent-based coupling solution (co-simulation) of the two platforms (GAMA and JASON). We finally experienced the model with a case of dynamic spread of the disease in Niamey (Niger) for which data were available

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Benavides, Helbig Jesús. "Para una historia de las sociedades mercantiles catalanas. Estudio completo del Dietari Honzè de la Compañía Torralba (10 de mayo del 1434 – agosto del 1437)." Doctoral thesis, Universitat de Barcelona, 2017. http://hdl.handle.net/10803/462139.

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La tesis se basa, por una parte, en la transcripción completa del llamado “Dietari Honzè” de la Compañía catalana-aragonesa del mercader Johan de Torralba, que abarca del 10 de mayo del 1434 al 12 de agosto del 1437, y por otra, en el desarrollo de algunos de los temas interesantes que surgen con el estudio de la misma. Debido a la enorme cantidad de temas que aparecen, hemos decidido centrar el estudio preferentemente en el análisis de las operaciones mercantiles y financieras apuntadas en el citado dietario, tanto referidas a particulares, como a la deuda pública. En el fondo, lo que nos encontramos al revisar el Manual, es la descripción detallada, de una manera no intencionada ni corregida, de lo que estaba aconteciendo dentro de aquella sociedad de la Barcelona perteneciente al reino catalán aragonés de la primera mitad del siglo XV. Según la transcripción del “dietari honzé”, descubrimos que Johan Torralba, en 1434 era un mercader clásico, que, con el paso del tiempo, supo rentabilizar las vías abiertas por los operadores que le antecedieron, diversificando sus inversiones, interviniendo en el mercado de la deuda pública, concurriendo en el lucrativo negocio del corso, del préstamo y del rescate de cautivos. Fue en definitiva, un hombre del siglo XV, cuyo estudio nos permite poner en valor su época, sus capacidades y las de la sociedad en la que trabaja y defiende.
The thesis is based, on the one side, in the full transcription of the so-called "Dietari Honzé" of a catalan-aragonese Company owned by the merchant Johan de Torralba, who covers from May 10 of the 1434, to August 12 of the 1437, and, on the other side, in the development of some of the issues that come with the study of the manuscript. Due to the enormous amount of themes that appear, we have decided to focus the study on the analysis of the commercial and financial operations that are mentioned in the aforementioned diary, both preferably referred to individuals and public debt. Ultimately, what we got reviewing the Manual, is the detailed description, in a way that is not corrected intentionally, of what was happening within the society of the city of Barcelona, belonging to the catalan - aragonese Kingdom, of the first half of the century XV. According to the transcription of the "dietari honze", we discovered that Johan Torralba, in 1434 was a classic merchant, which, with the passage of time, was able to use the profitable routes opened by the operators who preceded him, diversifying their investments, by intervening in the market of public debt, concurring also in the lucrative business of “corso”, loan, and the rescue of captives. He was certainly a man of the 15th century, whose study allows us to put in value his time, their skills and those of society in which he works and defends.

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Nonat, Laure. "Monde funéraire de l'âge du Bronze ancien et moyen de la façade nord de l'Espagne jusqu'au sud-ouest de la France : identités et espaces." Thesis, Pau, 2017. http://www.theses.fr/2017PAUU1036/document.

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Ce travail de doctorat vise à valoriser la pertinence du concept du - complexe culturel atlantique -, pour les périodes du Bronze ancien et du Bronze moyen, à partir de l'analyse des manifestations funéraires documentées de la façade nord de l'Espagne jusqu'au sud-ouest de la France. Nous avons, effectivement, choisi pour cette réflexion, d'étudier les régions les moins visibles de la documentation du domaine atlantique afin, d'une part, de les valoriser individuellement, et d'autre part, de comprendre les relations qu'elles ont entretenues entre elles, mais aussi avec celles du domaine continental Ibérique. Sur cet espace méridional atlantique, les données ont été considérablement renouvelées ces trente dernières années, grâce au développement de l'activité archéologique préventive, et permettent ainsi de contextualiser celles issues des anciennes explorations. Notre objectif consiste à caractériser les solutions funéraires ainsi que les mobiliers qui ont été adoptés sur cet espace afin de définir et de délimiter les groupes culturels en présence. Pour cela, nous avons mis en place une double échelle d'analyse : - une micro-échelle centrée sur la Galice et le bassin de l'Adour, et - une macro-échelle, sur les régions centres et orientales de la façade atlantique Ibérique. La première échelle nous permet d'analyser la documentation de façon exhaustive, en intégrant des données inédites, tandis qu'avec la seconde, globale et synthétique, nous dressons un panorama général et critique sur celle des régions cantabriques et du Pays Basque espagnol. La conjugaison de ces deux approches nous permet d'effectuer des comparaisons variées sur la documentation de ces espaces et d'identifier de nombreuses convergences, en particulier à partir d'aspects de la culture matérielle qui n'avaient pas été abordés lorsque le concept du Bronze Atlantique a été bâti. Elles concernent, notamment, des mobiliers céramiques, mais aussi la réponse unanime de ces régions atlantiques face aux cultures de la Meseta : celle de l'immobilisme. Ces éléments ainsi que les changements funéraires qui se sont opérés entre le Bronze ancien et le Bronze moyen nous permettent de caractériser ce qu'il convient de considérer comme des dynamiques atlantiques communes. Enfin, notre base documentaire, constituée de plus de 260 sites, nous amène, également, à aborder la question des facteurs qui ont été à l'origine de la constitution des groupes culturels, multiples, de cet espace, en valorisant la place des influences extérieures, des substrats locaux ainsi que des obstacles topographiques dominants du paysage
This doctoral work to highlight the relevance of the - atlantic cultural complex - concept, spanning the ancient and middle Bronze age, based on the analysis of funeral manifestations documented throughout Northern Spain and South-Western France. The choice to study regions which remain less visible with respect to the available documentation on the atlantic domain, as a point of reference for this research, was done in order to acknowledge their individual value and to understand the relationships between these regions and with those of the continental iberian domain. Data for the meridional atlantic zone has considerably expanded over the past thirty years, thanks to the development of preventive archaeological activities, thus enabling the contextualisation of data from past explorations. The main objective of this research is to characterise the funeral finalities and furniture used by people in this area, in order to define and delimit different cultural groups. In order to do this we used a double-scale for analysis : a micro-scale centered on Galicia and the Adour basin, and a macro-scale encompassing the central and east-central front of atlantic Iberia. The first scale allowed us to analyse the data in a very exhaustive manner, integrating brand-new data, whereas with the second scale, which is much more global and synthetic, we established a general and critical panorama of the data for the cantabrian and Basque regions of Spain. The combination of these two approaches allows us to establish a variety of comparisons on the documentation about these areas, and to identify many convergences, especially with regards to material culture that had not been addressed when constructing the Atlantic Bronze concept. This includes pottery items, as well as a certain immobilism on behalf of the atlantic regions in response to the Meseta cultures. These elements, along with funeral changes that occurred between the ancient and middle Bronze age allow us to characterise what can be considered as the common atlantic dynamics. Lastly, our database of over 260 sites, raises the question of what factors might have caused the composition of the various different cultural groups in the area, emphasizing the role played by exterior influences, local substrates and topographical obstacles
Ese trabajo de doctorado pretende valorar la pertinencia del concepto del - complejo cultural atlántico -, para los periodos del Bronce antiguo y medio, mediante el análisis de las manifestaciones funerarias documentadas de la fachada norte de España hasta el suroeste de Francia. Hemos elegido para esta reflexión el estudio de las regiones menos visibles de la documentación del ámbito atlántico con el fin, por una parte, de valorar cada una de ellas individualmente, y por otra, de comprender los tipos de relaciones que mantenían entre ellas, pero también, con las del ámbito continental Ibérico. Sobre ese espacio meridional atlántico, los datos se incrementaron de forma significativa estos últimos treinta años, gracias al desarrollo de la actividad arqueológica preventiva, y permiten, por lo tanto, contextualizar las que provienen de las antiguas exploraciones. Nuestro objetivo consiste en caracterizar las soluciones funerarias así como los mobiliarios que han sido adoptados, para definir y delimitar los grupos culturales presentes en ese espacio. Para eso, hemos procesado a una doble escala de análisis: - una micro-escala centrada sobre Galicia y la cuenca del Adour, y una macro-escala, sobre las regiones centrales y orientales de la fachada atlántica Ibérica. La primera escala nos permite analizar la documentación de forma exhaustiva, integrando datos inéditos a nuestro discurso, mientras que, con la segunda, global y sintética, establecemos un panorama general y crítico de Asturias, Cantabria y del País Vasco. La combinación de estos dos tipos de enfoques nos permite efectuar unas variadas comparaciones sobre la documentación de esos espacios e identificar numerosas convergencias, en particular en relación con aspectos de la cultura material que no habían sido tratados cuando el concepto del Bronce Atlántico nació. Estas implican, especialmente, los recipientes cerámicos, pero también la respuesta unánime de las regiones atlánticas hacia las culturas de la Meseta: la del inmovilismo. Esos elementos, así como los cambios funerarios que se operan entre el Bronce antiguo y el Bronce medio, nos permite caracterizar lo que conviene considerar como una dinámica atlántica común. Por fin, nuestra base documental, constituida por más de 260 yacimientos, nos lleva a abordar la cuestión de los factores que han estado en el origen de la constitución de los grupos culturales, múltiples, de este espacio, valorizando el papel de las influencias exteriores, de los substratos locales, así como de los obstáculos topográficos dominantes del paisaje

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Volkart, Priscylla Andrade. "Estudo de ?ons cobre no mecanismo de forma??o de complexo com resveratrol em modelo de c?lulas MCF-7." Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2017. http://tede2.pucrs.br/tede2/handle/tede/7590.

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES
The redox-active chemical properties of trace element copper make it an essential cofactor for several cellular mechanisms, as for ROS production. Polyphenols have been used in the pro-oxidant mechanism of action of interaction with endogenous Cu (II) ions for the production of reactive oxygen species in excess as a treatment for malignancies, leading to apoptosis. This work studied Cu (II) ions in the complex formation mechanism with Resveratrol in MCF-7 cells model. We analyzed the selectivity of Resveratrol in relation to the cupric metal ion using HPLC (High-Performance Liquid Chromatography) and the formation of the compound Resveratrol-Copper through UV-VIS (Ultra-Violet Visible Spectrophotometry). We analyzed the cellular morphology and location of the metal ion by MET-EDS (Electronic Transmission microscopy with Dispersive X-ray Spectroscopy). Cell death by apoptosis and quantification of ROS in said cell line with copper enrichment and treated with Resveratrol was made by flow cytometry. The results show the selectivity of the polyphenol compound by copper ion as well as the formation of the complex Resveratrol-Copper in extracellular conditions, however even with verification of endogenous copper accumulation in physiological conditions in vitro, the formation of that complex did not occur because there was no production of ROS and therefore, no cell death. In short, our research reveals that for in vitro conditions for the MCF-7 line, there's no Resveratrol-Copper complex formation as observed in sub-lethal quantities of chemically enriched cells with CuSO4 and treated with Resveratrol.
As propriedades qu?micas redox-ativas do oligoelemento cobre o tornam cofator essencial para diversos mecanismos celulares como o de produ??o de ROS. Polifen?is v?m sendo utilizados no mecanismo de a??o pr?-oxidante de intera??o com ?ons Cu (II) end?geno para a produ??o dessas esp?cies oxig?nio reativas em excesso como tratamento de malignidades, levando a apoptose. O presente trabalho estudou os ?ons Cu (II) no mecanismo de forma??o do complexo com Resveratrol em modelo de c?lulas MCF-7. Analisamos a seletividade do Resveratrol frente ao ?on met?lico c?prico utilizando CLAE (Cromatografia L?quida de Alta Efici?ncia) e verificou-se a forma??o do complexo Resveratrol-Cobre por meio de UV-VIS (Espectrofotometria de Ultra-Violeta Vis?vel). Analisou-se a morfologia celular e localiza??o do ?on met?lico por MET-EDS (Microscopia de Transmiss?o Eletr?nica com Espectroscopia Dispersiva de Raios-X). Morte celular por apoptose e quantifica??o de ROS na linhagem enriquecida com cobre e tratadas com Resveratrol foi feita por Citometria de Fluxo. Os resultados mostram a seletividade do composto polifen?lico pelo ?on cobre bem como a forma??o do complexo Resveratrol-Cobre em condi??es extracelulares, por?m mesmo com a verifica??o de ac?mulo de cobre end?geno, em condi??es fisiol?gicas in vitro n?o foi constatada a forma??o do referido, pois n?o houve forma??o de ROS e morte celular conseguinte. Em suma, Nossa pesquisa revela que em condi??es in vitro para a linhagem MCF-7, n?o h? forma??o de complexo Resveratrol-Cobre como observado quimicamente em quantidades sub-letais de c?lulas enriquecidas com CuSO4 e tratadas com Resveratrol.

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Huvent, Isabelle. "Oncogénicité des cellules transformées par l'adénovirus 12 : régulation d'un promoteur de classe I du CMH et du domaines des protéines E1A impliqués dans la résistance à la lyse par les cellules NK." Lille 1, 1997. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/1997/50376-1997-67.pdf.

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Tous les stéréotypes d'adénovirus humains (ad) transforment les cellules primaires de rongeurs mais seules les cellules transformées par les adénovirus des sous-groupes a et b sont tumorigenes pour les animaux immunocompetents. Les cellules transformées par ces stéréotypes échappent au contrôle du système immunitaire par deux mécanismes: inhibition de l'expression des antigènes de classe i du cmh et résistance a la lyse par les cellules nk. Ces deux mécanismes sont sous le contrôle de la région e1a et sont mutuellement requis pour conférer aux cellules transformées le phénotype oncogénique. Le domaine de la grande protéine e1a de l'ad12 nécessaire à la résistance à la lyse par les cellules nk s'étend du cr2 au second exon et inclut un domaine riche en alanine présent entre le cr2 et le cr3 des protéines e1a des adénovirus oncogéniques (ad12 et sa7). L'inhibition de l'expression des antigènes de classe i du cmh a lieu au niveau transcriptionnel. De nombreux éléments du promoteur du gène h-2k#b interviennent dans cette régulation. L'activité du promoteur minimal est plus faible dans les cellules transformée par l'ad12. L'enhancer a est actif dans les cellules transformées par l'ad2 mais inactif dans celles qui sont transformées par l'ad12. Par contre, la présence d'une caat box inversée participe à l'activation de la transcription dans ces dernières. De plus, plusieurs éléments interviennent négativement dans la transcription du gène h-2k#b dans les cellules transformées par l'ad2 notamment une structure potentielle en épingle à cheveux.

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Jaisson, Pascal. "Systèmes complexes gouvernés par des flux : schémas de volumes finis hybrides et optimisation numérique." Phd thesis, Ecole Centrale Paris, 2006. http://tel.archives-ouvertes.fr/tel-00468203.

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Cette thèse concerne la modélisation par des EDP et la résolution numérique de problèmes d'optimisation pour les flux d'information et pour le trafic routier. Nous proposons un nouveau type de schémas hybrides. En premier, nous nous intéressons à l'optimisation des temps de service nécessaires à un serveur informatique pour traiter un ou plusieurs types de requêtes, afin de satisfaire une qualité de service imposée. La modélisation choisie fait intervenir un système de lois de conservation proposé par De Vuyst. Les particules sont les requêtes et la variable d'espace représente le taux d'avancement dans le traitement de la requête. Nous exhibons alors les équations différentielles ordinaires permettant de calculer les temps de service. Cela nous permet d'optimiser l'allocation des ressources du serveur suivant le type de requêtes. Nous présentons deux exemples de simulation numérique. Ensuite, nous considérons un problème d'optimisation en trafic routier faisant intervenir le modèle "fluide" aux EDP du second ordre de Aw-Rascle. Les particules sont les véhicules. A partir de données observées, en quantité limitée, sur une portion de route [0;L] et sur un intervalle de temps [0;T], nous voulons prévoir les conditions de circulation après le temps T. Il faut connaître précisément les conditions aux temps T pour les utiliser dans le système de Aw-Rascle comme nouvelles conditions initiales. Nous calculons cette condition initiale en retrouvant par un algorithme d'optimisation la solution de Aw-Rascle qui minimise l'erreur entre les valeurs de cette solution et les données observées. Il s'agit d'un problème d'assimilation de données, que nous résolvons par une méthode adjointe. Deux stratégies distinctes sont possibles : nous prenons comme variables d'optimisation les conditions initiales et les conditions aux bords du domaine [0;L]x [0;T] ou alors nous prenons uniquement comme variables d'optimisation les conditions initiales sur une section plus grande [-L';L]. Nous explorons ces deux stratégies. Enfin, nous nous intéressons aux schémas numériques permettant de trouver les solutions des systèmes de lois de conservation tels que les deux systèmes précédents. Nous présentons alors un nouveau type de schémas hybrides à un paramètre qui permet d'obtenir la propriété TVD et d'être du second ordre en espace et en temps. Le paramètre permet d'interpoler les schémas de Lax-Wendroff et de Lax-Friedrichs. Après cette première phase prédictrice, il est possible de corriger ce paramètre dans les cellules où il y a production d'entropie numérique. Nous obtenons ainsi un schéma qui permet de capturer la solution physique.

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Santos, Raquel La Corte dos. "Sujeito-língua-tecnologia: marcas de uma relação complexa em enunciados produzidos em diferentes práticas de ensino/aprendizagem de Espanhol (EAD e presencial) em meio digital." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/8/8145/tde-23112015-142511/.

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Nesta tese discute-se, a partir de um olhar teórico multidisciplinar, a relação entre sujeito, língua e tecnologias que se manifesta em enunciados produzidos em meio digital, no contexto de práticas pedagógicas de duas modalidades de educação a Educação a Distância (EAD) e a Educação Presencial (EP), em cursos superiores de Letras/Espanhol. Tem como objetivo principal contribuir para uma reflexão crítica sobre o papel exercido por diferentes tecnologias de suporte da escrita, surgidas no cenário da cibercultura, na relação entre sujeitos aprendizes e mediadores e também se propõe a observar de que forma essas tecnologias afetam o processo de ensino e aprendizagem de línguas estrangeiras, neste caso concretamente o espanhol por parte de falantes do português brasileiro. Para tanto, faz uso de uma metodologia qualitativa, com técnicas de observação participante e, nesse campo, de um conjunto de procedimentos de pesquisa, de natureza exploratória, etnográfica, auto-etnográfica e de descrição linguística, sem, no entanto, enveredar no que se conhece como análise de erros. As interpretações foram feitas a partir da análise de enunciados em fóruns digitais da EAD e da descrição de práticas pedagógicas híbridas, incluindo enunciados em meio digital, produzidos nessas práticas. Os resultados apontam para a necessidade de uma maior reflexão sobre enunciados produzidos em meio digital, em processos de ensino e aprendizagem, observando-os como objetos híbridos e complexos, que podem comportar informações sobre a postura do sujeito, tanto na relação com a língua estrangeira e as tecnologias quanto sobre a especificidade da cibercultura, assim como sobre a forma como esta molda novas formas de escrita e novas relações sócio-afetivas e comunicativas.
This thesis discusses, from a multidisciplinary theoretical standpoint, the relationship among individual (understood as a complex subject), language and technologies that manifests itself in utterances produced in digital media, in the context of teaching practices of two kinds - Distance Learning (DL) and Classroom Teaching (CT), in university degrees in Languages (Spanish). The main objective is to contribute to a critical reflection on the role played by different technologies that support writing, which emerged in the scenario of cyberculture, in the relationship involving learners and mediators. The research also intends to observe how these technologies affect the teaching and learning of foreign languages, in this specific case, the Spanish learned by speakers of Brazilian Portuguese. To achieve its objective, a qualitative methodology is used, counting on participant observation techniques, and in this field, making use of a set of research procedures, which take the form of exploratory, ethnographic, auto-ethnographic and linguistic description research. However, error analysis is not used. The interpretations were made from the analysis of utterances set out in digital forums (DL) and from the description of hybrid pedagogical practices, including utterances digitally produced as part of these practices. The results point to the need for further reflection on utterances produced in digital media in teaching and learning processes, watching them as hybrid and complex objects, which can include information about the individuals attitudes. These can be related to the persons relationship with the foreign language and technologies, the specificity of cyberculture, as well as how cyberculture shapes new forms of writing and new socio-affective and communicative relationships.

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Araújo, Maurício Viana de. "O ensino-aprendizagem de produção textual no ensino a distância em uma perspectiva complexa e transdisciplinar." Pontifícia Universidade Católica de São Paulo, 2015. https://tede2.pucsp.br/handle/handle/13733.

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This study aimed to describe and interpret the teaching-learning process of textual production, as a phenomenon of human experience, in a distance course designed to undergraduate students, from a complex and transdisciplinary perspective. The students and teacher s experiences were researched on when the teaching-learning space was shared by them in the virtual Moodle environment, seeking to gather subsidies to develop future online writing courses and/or online teacher education programs. The research is theoretically founded on complexity theory (MORIN, 2003, 2008, 2013), with relevance in its recursive, dialogic and hologramatic principles; and on transdisciplinarity (NICOLESCU, 2001,2008), by focusing on levels of reality and the included third logic. This study was methodologically grounded on the hermeneutic-phenomenological approach (FREIRE, 2007, 2010, 2012; van MANEN 1990), a methodology that aims at describing and interpreting human experience phenomena to search for their essences. To identify the hermeneutic-phenomenological themes, the interpretation procedures were undertaken through textualization, thematization (which was operationalized by means of refinement and remeaning), and validating cicle. In this research, the phenomenon interpretation revealed six hermeneutic-phenomenological themes: concern, flaming, time, fear, difficulty and recognition
O objetivo deste trabalho foi descrever e interpretar o ensino-aprendizagem da produção textual, como fenômeno da experiência humana, num curso de língua materna a distância para graduandos, em uma perspectiva complexa e transdisciplinar. Foram investigadas as vivências e experiências dos alunos e do professor, ao compartilharmos um espaço de ensinoaprendizagem textual no ambiente virtual Moodle, buscando obter subsídios para a elaboração de futuros programas de cursos de produção textual a distância e para a formação de professores para essa modalidade de ensino-aprendizagem. O trabalho foi fundamentado teoricamente na complexidade (MORIN, 2003, 2008, 2013), tendo como referência os seus princípios recursivo, dialógico e hologramático, e na transdisciplinaridade (NICOLESCU, 2001,2008), tendo em vista os níveis de realidade e a lógica do terceiro incluído. A metodologia de pesquisa adotada foi a abordagem hermenêutico-fenomenológica (FREIRE, 2007, 2010, 2012; van MANEN 1990), uma metodologia qualitativa de pesquisa, cujo objetivo é descrever e interpretar fenômenos da experiência humana, em busca de suas essências. Os procedimentos interpretativos, com vistas à identificação dos temas hermenêutico-fenomenológicos, são realizados por meio da textualização das experiências, de sua tematização (operacionalizada pelos movimentos de refinamento e ressignificação) e do ciclo de validação. Nesta pesquisa, a interpretação do fenômeno revelou seis temas hermenêutico-fenomenológicos - preocupação, flaming, tempo, medo, dificuldade e reconhecimento como constituintes do fenômeno em estudo

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Garnier, Aurélie. "Dynamiques neuro-gliales locales et réseaux complexes pour l'étude de la relation entre structure et fonction cérébrales." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066562/document.

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L'un des enjeux majeurs actuellement en neurosciences est l'élaboration de modèles computationnels capables de reproduire les données obtenues expérimentalement par des méthodes d'imagerie et permettant l'étude de la relation structure-fonction dans le cerveau. Les travaux de modélisation dans cette thèse se situent à deux échelles et l'analyse des modèles a nécessité le développement d'outils théoriques et numériques dédiés. À l'échelle locale, nous avons proposé un nouveau modèle d'équations différentielles ordinaires générant des activités neuronales, caractérisé et classifié l'ensemble des comportements générés, comparé les sorties du modèle avec des données expérimentales et identifié les structures dynamiques sous-tendant la génération de comportements pathologiques. Ce modèle a ensuite été couplé bilatéralement à un nouveau compartiment modélisant les dynamiques de neuromédiateurs et leurs rétroactions sur l'activité neuronale. La caractérisation théorique de l'impact de ces rétroactions sur l'excitabilité a été obtenue en formalisant l'étude des variations d'une valeur de bifurcation en un problème d'optimisation sous contrainte. Nous avons enfin proposé un modèle de réseau, pour lequel la dynamique des noeuds est fondée sur le modèle local, incorporant deux couplages: neuronal et astrocytaire. Nous avons observé la propagation d'informations différentiellement selon ces deux couplages et leurs influences cumulées, révélé les différences qualitatives des profils d'activité neuronale et gliale de chaque noeud, et interprété les transitions entre comportements au cours du temps grâce aux structures dynamiques identifiées dans les modèles locaux
A current issue in neuroscience is to elaborate computational models that are able to reproduce experimental data recorded with various imaging methods, and allowing us to study the relationship between structure and function in the human brain. The modeling objectives of this work are two scales and the model analysis need the development of specific theoretical and numerical tools. At the local scale, we propose a new ordinary differential equations model generating neuronal activities. We characterize and classify the behaviors the model can generate, we compare the model outputs to experimental data and we identify the dynamical structures of the neural compartment underlying the generation of pathological patterns. We then extend this approach to a new neuro-glial mass model: a bilateral coupling between the neural compartment and a new one modeling the impact of astrocytes on neurotransmitter concentrations and the feedback of these concentrations on neural activity is developed. We obtain a theoretical characterization of these feedbacks impact on neuronal excitability by formalizing the variation of a bifurcation value as a problem of optimization under constraint. Finally, we propose a network model, which node dynamics are based on the local neuro-glial mass model, embedding a neuronal coupling and a glial one. We numerically observe the differential propagations of information according to each of these coupling types and their cumulated impact, we highlight qualitatively distinct patterns of neural and glial activities of each node, and link the transitions between behaviors with the dynamical structures identified in the local models

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Vital, Ang?lica Belchior. "S?ntese e caracteriza??o de rutenato de b?rio." Universidade Federal do Rio Grande do Norte, 2015. http://repositorio.ufrn.br/handle/123456789/20238.

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)
Compostos contendo rut?nio possuem vasta aplica??o em processos catal?ticos. Muitas vezes esse metal ? utilizado em ?xidos porosos , suporte, com alta estabilidade t?rmica. Os ?xidos mistos do tip o perovskita (ABO 3 ) apresentam boa dispers?o met?lica , elevada estabilidade t?rmica e qu?mica, sendo empregados em processos oxidativos . Em vista disso, este trabalho teve como objetivo principal sintetizar e caracterizar o catalisador de rutenato de b?rio (BaRuO 3 ) com estrutura do tipo perovskita. Para isso, foram utilizadas duas metodolog ias de s?ntese de BaRuO 3 , a complexa??o combinada EDTA - Citrato e a coprecipita??o em meio oxalato. BaRuO 3 produzido passou por tratamentos t?rmicos a 950?C por 5, 10 e 15 horas. O precursor foi utilizado na an?lise termogravim?trica (TG) para avaliar a estabilidade t?rmica, e os p?s cer?micos calcinados foram caracterizados por: difra??o de raios X (DRX) para identifica??o das fases formadas , an?lise estrutural e avalia?? o do tamanho m?dio de cristalitos; microscopia eletr?nica de varredura (MEV) para observa??o da morfologia; espectroscopia de energia dispersiva (EDS) para determina??o da composi??o qu?mica local. Observou - se que pela metodologia EDTA - Citrato o BaRuO 3 apr esentou estrutura rombo?drica com o grupo espacial R - 3mH (ICSD: 10253) com morfologia heterog?ne a e com larga distribui??o de tamanho de cristais. Por outro lado, o ?xido sintetizado pelo m?todo de coprecipita??o apresentou dois polimorfos, um com estrutura hexagonal com o grupo e spacial P63/mmc (ICSD:84652) e outro rombo?drico (ICSD:10253), com morfologia homog?nea e maior controle de distribui??o de cristais.
Ruthenium compounds are widely use d in catalytic processes. Often this metal is supported on porous oxides having high thermal stability. Perovskite - type o xides (ABO 3 ) have good metal dispersion , high thermal and chemical s tability, it are used in oxidative processes . T his study aimed to synthesize and characterize barium ruthenate (BaRuO 3 ) with perovskite - type structure. For this, two methods for BaRuO 3 synthesis have been used , combined complexation EDTA - Citrate and oxalat e coprecipitation. BaRuO 3 produced underwent heat treatment at 950 ? C for 5, 10 and 15 hours. The precursor was used in thermogravimetric analysis (TG) to evaluate thermal stability , ceramic powders obtained were characterized by X - ray diffraction (XRD) t o identify the phases, structural analysis and assessment of the average size of crystallites; scanning electron microscopy (SEM) to observe the morphology; energy dispersive spectroscopy (EDS) to determine local chemical composition. It was observed that BaRuO 3 for EDTA - citrate methodology presented rhombohedral structure with space group R - 3mH ( ICSD : 10253) heterogeneous morphology with a broad distribution and crystal size. thereby , the oxide synthesized by oxalate coprecipitation method presented two po lymorphs, with hexagonal structure with space group P63/ mmc ( ICSD : 84652) and a rhombohedral ( ICSD : 10253) with homogeneous morphology and crystals distribution control.

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Medeiros, Indira Aritana Fernandes de. "Obten??o de ferrita de cobalto atrav?s de dois m?todos de s?ntese: m?todo de complexa??o combinando EDTA/Citrato e m?todo hidrot?rmico." Universidade Federal do Rio Grande do Norte, 2013. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15848.

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
In this work it was synthesized and characterized the cobalt ferrite (CoFe2O4) by two methods: complexation combining EDTA/Citrate and hydrothermal investigating the influence of the synthesis conditions on phase formation and on the crystallite size. The powders were mainly characterized by x-ray diffraction. In specific cases, it was also used scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), x-ray fluorescence (XRF) and isotherms of adsorption and desorption of nitrogen (BET method). The study of the crystallite size was based on the interpretation of x-ray diffractograms obtained and estimated by the method of Halder-Wagner-Scherrer and Langford. An experimental design was made in order to assist in quantifying the influence of synthesis conditions on the response variables. The synthesis parameters evaluated in this study were: pH of the reaction medium (8, 9 and 10), the calcination temperature (combined complexation method EDTA/Citrate 600?C, 800?C and 1000?C), synthesis temperature (hydrothermal method 120?C, 140?C and 160?C), calcination time (combined complexation method EDTA/Citrate - 2, 4 and 6 hours) and time of synthesis (hydrothermal method 6, 15 and 24 hours). By the hydrothermal method was possible to produce mesoporous powders with high purity, with an average crystallite size up to 7 nm, with a surface area of 113.44 m?/g in the form of pellets with irregular morphology. By using the method of combined complexation EDTA/Citrate, mesoporous powders were produced with greater purity, crystallite size up to 22nm and 27.95 m?/g of surface area in the form of pellets with a regular morphology of plaques. In the experimental design was found that the hydrothermal method to all the studied parameters (pH, temperature and time) have significant effect on the crystallite size, while to the combined complexation method EDTA/Citrate, only temperature and time were significant
Neste trabalho foi sintetizada e caracterizada a ferrita de cobalto (CoFe2O4) atrav?s dos m?todos complexa??o combinada EDTA/Citrato e hidrot?rmico, investigando a influ?ncia das condi??es de s?ntese na forma??o da fase e no tamanho m?dio de cristalito. Os p?s foram caracterizados principalmente por difra??o de raios-x. Em casos espec?ficos, tamb?m foi utilizado microscopia eletr?nica de varredura (MEV), espectroscopia de energia dispersiva (EDS), fluoresc?ncia de raios-x (FRX) e isotermas de adsor??o e dessor??o de nitrog?nio (M?todo BET). O estudo do tamanho de cristalito foi baseado na interpreta??o dos difratogramas de raios-x obtidos e estimado atrav?s do m?todo de Halder-Wagner-Langford (HWL) e de Scherrer. Um planejamento experimental foi realizado com a finalidade de auxiliar na quantifica??o da influ?ncia das condi??es de s?ntese nas vari?veis-resposta. Os par?metros de s?ntese avaliados neste trabalho foram: pH do meio reacional (8, 9 e 10), temperatura de calcina??o (m?todo de complexa??o combinando EDTA/Citrato 600?C, 800?C e 1000?C), temperatura de s?ntese (m?todo hidrot?rmico 120?C, 140?C e 160?C), tempo de calcina??o (m?todo de complexa??o combinando EDTA/Citrato 2, 4 e 6 hrs) e tempo de s?ntese (m?todo hidrot?rmico 6, 15 e 24 hrs). Pelo m?todo hidrot?rmico foi poss?vel produzir p?s mesoporosos com elevado grau de pureza, com tamanho m?dio de cristalito de at? 7nm, com ?rea superficial de 113,44m?/g e na forma de aglomerados com morfologia irregular. Ao se utilizar o m?todo de complexa??o combinando EDTA/Citrato foram produzidos p?s mesoporosos com maior pureza, cristalitos com at? 22nm de tamanho, 27,95m?/g de ?rea superficial e na forma de aglomerados com morfologia regular de placas. No planejamento experimental foi constatado que no caso do m?todo hidrot?rmico todos os par?metros estudados (pH, Temperatura e tempo) apresentam efeito significativo no tamanho de cristalito, enquanto que, para o m?todo de complexa??o combinando EDTA/Citrato, apenas a temperatura e o tempo foram significativos
2020-01-01

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Cavalini, Eliseu Antonio [UNESP]. "Filmes nanométricos obtidos a plasma da mistura ácido cítrico-etilenoglicol-metal complexador." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/147126.

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Plasmas de gases e / ou vapores orgânicos produzem filmes finos ou pós apresentando características poliméricas, especialmente quando os plasmas são derivados de monômeros das famílias dos hidrocarbonetos alcoóis, siloxanos, silazanos, e outro. Neste trabalho, os filmes finos foram obtidos a partir da mistura de ácido cítrico-etilenoglicol-metal complexador depositado a plasma, com 13,56 MHz de radiofrequência na potência de 10 a 50 W e pressão fixada a 10 Pa. Os resultados da análise de espectroscopia de infravermelho FTIR mostrou que os grupos vibracionais dos filmes estavam preservados, mas com modificações em suas estruturas moleculares. Foram observados nos resultados obtidos por espectroscopia fotoelétrica de raios-X modificações na composição química da ligação oxigênio-carbono e oxigênio-hidrogênio com variação da potência de 10 a 50 W. A taxa de deposição dos filmes finos diminuiu de 0,10 a 0,08 nm/minuto com o aumento da potência de 10 a 50 W. As propriedades óticas das amostras como o índice de refração, coeficiente de absorção, gap ótico foram investigados por espectroscopia UV- visível. Destas análises foram possíveis obter valores n de 1,54 a 1,50 e energia do gap entre 4,75 e 4,85 eV. A técnica de ângulos de contato e foi utilizada para investigar a molhabilidade das amostras, que apresentaram caráter hidrofílico em todas as condições de deposição dos filmes. A técnica de EDS foi usada para investigar as composições químicas das amostras. Além disso, os filmes obtidos apresentaram valores de condutividade elétrica superior a 10-8 (Ωcm)-1 e constantes dielétricas entre 2,4 e 2,7.
Plasmas from gases and / or organic vapors produce thin films or powders presenting polymeric characteristics, especially when the plasmas are derived from monomers of the families of hydrocarbons, alcohols, siloxanes, silazanes, and others. In this work, thin films were obtained by citric acid / ethylene glycol / complex metal deposited by 13.56 MHz RF plasma at 10 and 50 W fixed pressure 10 Pa. FTIR spectroscopy showed that the main vibrational groups of the films were preserved, but with modifications in their molecular structures. It was observed by X –ray photoelectron spectroscopy chemical composition modifications in oxygen – carbon and oxygen – hydrogen bond while the deposition power changed from 10 to 50 W. The deposition rate of the samples decreased from 0.10 to 0.08 nm / minute while the RF power increases from 10 to 50 W. The samples optical properties as refractive index n, absorption coefficient, optical gap Eg were investigated by UV – Visible spectroscopy. From these analysis were possible to obtain values of n from 1.54 to 1.50 and Eg between 4.75 and 4.85 eV. Contact angle and surface energy measurements were used to investigate the wettability of composite Polymer films, for all depositions conditions the films presented hydrophilic character. EDS was used investigate components of the samples. Moreover, the film showed electrical conductivity values greater than 10-8(Ωcm)-1 and dielectric constant between 2.2 and 2.7.

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Garnier, Aurélie. "Dynamiques neuro-gliales locales et réseaux complexes pour l'étude de la relation entre structure et fonction cérébrales." Electronic Thesis or Diss., Paris 6, 2015. http://www.theses.fr/2015PA066562.

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L'un des enjeux majeurs actuellement en neurosciences est l'élaboration de modèles computationnels capables de reproduire les données obtenues expérimentalement par des méthodes d'imagerie et permettant l'étude de la relation structure-fonction dans le cerveau. Les travaux de modélisation dans cette thèse se situent à deux échelles et l'analyse des modèles a nécessité le développement d'outils théoriques et numériques dédiés. À l'échelle locale, nous avons proposé un nouveau modèle d'équations différentielles ordinaires générant des activités neuronales, caractérisé et classifié l'ensemble des comportements générés, comparé les sorties du modèle avec des données expérimentales et identifié les structures dynamiques sous-tendant la génération de comportements pathologiques. Ce modèle a ensuite été couplé bilatéralement à un nouveau compartiment modélisant les dynamiques de neuromédiateurs et leurs rétroactions sur l'activité neuronale. La caractérisation théorique de l'impact de ces rétroactions sur l'excitabilité a été obtenue en formalisant l'étude des variations d'une valeur de bifurcation en un problème d'optimisation sous contrainte. Nous avons enfin proposé un modèle de réseau, pour lequel la dynamique des noeuds est fondée sur le modèle local, incorporant deux couplages: neuronal et astrocytaire. Nous avons observé la propagation d'informations différentiellement selon ces deux couplages et leurs influences cumulées, révélé les différences qualitatives des profils d'activité neuronale et gliale de chaque noeud, et interprété les transitions entre comportements au cours du temps grâce aux structures dynamiques identifiées dans les modèles locaux
A current issue in neuroscience is to elaborate computational models that are able to reproduce experimental data recorded with various imaging methods, and allowing us to study the relationship between structure and function in the human brain. The modeling objectives of this work are two scales and the model analysis need the development of specific theoretical and numerical tools. At the local scale, we propose a new ordinary differential equations model generating neuronal activities. We characterize and classify the behaviors the model can generate, we compare the model outputs to experimental data and we identify the dynamical structures of the neural compartment underlying the generation of pathological patterns. We then extend this approach to a new neuro-glial mass model: a bilateral coupling between the neural compartment and a new one modeling the impact of astrocytes on neurotransmitter concentrations and the feedback of these concentrations on neural activity is developed. We obtain a theoretical characterization of these feedbacks impact on neuronal excitability by formalizing the variation of a bifurcation value as a problem of optimization under constraint. Finally, we propose a network model, which node dynamics are based on the local neuro-glial mass model, embedding a neuronal coupling and a glial one. We numerically observe the differential propagations of information according to each of these coupling types and their cumulated impact, we highlight qualitatively distinct patterns of neural and glial activities of each node, and link the transitions between behaviors with the dynamical structures identified in the local models

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Chatelin, Robin. "Méthodes numériques pour l'écoulement de Stokes 3D : fluides à viscosité variable en géométrie complexe mobile : application aux fluides biologiques." Phd thesis, Université Paul Sabatier - Toulouse III, 2013. http://tel.archives-ouvertes.fr/tel-00946993.

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Ce travail propose des méthodes numériques pour la résolution du problème de Stokes en géométrie complexe pour des fluides non homogènes. Ce modèle décrit l'écoulement d'un fluide très visqueux, incompressible, dont la viscosité n'est pas uniforme mais dépend de la concentration d'un certain agent. D'un point de vue mathématique, il s'agit de résoudre un problème elliptique couplé à une équation de convection-diffusion, qui génèrent une dynamique non linéaire. L'algorithme de résolution est basé sur une discrétisation hybride utilisant une grille et des particules. Des algorithmes à pas fractionnaires permettent de séparer la résolution des différents phénomènes pour profiter des avantages spécifiques à ces discrétisations: méthodes lagrangiennes adaptées à la convection et méthodes eulériennes pour la diffusion. Une méthode de pénalisation permet de gérer efficacement l'interaction entre le fluide et la géométrie mobile du domaine. Une méthode de projection itérative est développée pour ce problème quasi-statique, cela permet d'utiliser des solveurs rapides propices aux calculs en grande dimension. Plusieurs cas tests viennent valider la convergence, la conservation et les performances de l'algorithme en 3D. Ce travail s'inscrit dans le contexte de l'étude de l'écoulement du mucus pulmonaire autour des cellules épithéliales ciliées tapissant les bronches. L'efficacité du transport du mucus, assurant la capture et l'expectoration des agents pathogènes, est étudiée en fonction des paramètres biologiques. D'autres simulations d'un micro-nageur et d'écoulements en milieux poreux complètent cette étude.

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Cornejo, Stewart Josefina. "El caso Netflix 2012-2015. Nuevas formas de pensar la producción, distribución y consumo de series dramáticas." Doctoral thesis, Universitat Ramon Llull, 2016. http://hdl.handle.net/10803/386244.

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Aquesta investigació explora el panorama de sèries dramàtiques nord-americanes que ha arribat amb el nou segle, a partir d'un estudi en profunditat d'aquest nou model serial que inclou diferents categories d'anàlisi i que es reconeix com la Tercera Edat d'Or de la Televisió. Així, es relacionarà el model que introdueix aquesta etapa amb els continguts originals de Netflix com la companyia pionera en la producció de sèries dramàtiques per streaming , deixant al descobert que la Tercera Edat d'Or de la Televisió transcendeix a l'aparell televisiu i les característiques que havien imperat en el seu model. D'aquesta manera, s'estudiarà el cas de Netflix i la seva producció de sèries dramàtiques (2012-2015) posant especial atenció a tres casos paradigmàtics -House of Cards, Orange is the New Black i The Killing-, per tal d'indagar sobre les novetats que introdueix la companyia al moment de pensar la producció, distribució i consum de sèries dramàtiques.
Esta investigación explora el panorama de series dramáticas estadounidenses que ha llegado con el nuevo siglo, a partir de un estudio en profundidad de este nuevo modelo serial que incluye diferentes categorías de análisis y, que se reconoce como la Tercera Edad de Oro de la Televisión. Así, se relacionará el modelo que introduce esta etapa con los contenidos originales de Netflix como compañía pionera en la producción de series dramáticas para streaming, dejando al descubierto que la Tercera Edad de Oro de la Televisión trasciende al aparato televisivo y las características que habían imperado en su modelo. De esta forma, se estudiará el caso de Netflix y su producción de series dramáticas (2012-2015) prestando especial atención a tres casos paradigmáticos -House of Cards, Orange is the New Black y The Killing-, con el fin de indagar sobre las novedades que introduce la compañía al momento de pensar la producción, distribución y consumo de series dramáticas.
This research explores the landscape of American dramatic series born in the new century trough an in depth analysis of the new model of series that includes different categories and is recognized as the Third Golden Age of Television. Thus, it will be relate this new model with Netflix originals content, as a company pioneer in the production of dramatic series for streaming, letting uncovered that the Third Golden Age of Television transcends the TV device and the characteristics of its model. Therefore, we will study the Netflix case and its production of dramatic series (2012-2015) given special consideration to three pragmatic cases –House of Cards, Orange is the New Black and The Killing-, with the aim to examine the innovations that the company introduces when it comes to production, distribution and consumption of dramatic series.

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Furtado, Valéria de Almeida. "A formação em serviço do tutor de educação a distância sob a ótica do pensamento complexo: a construção de uma identidade." Pontifícia Universidade Católica de São Paulo, 2009. https://tede2.pucsp.br/handle/handle/10178.

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In 2002, the Secretary of Education for the State of Minas Gerais began implementation of the Teaching College Course, in the distance learning modality, which was denominated Veredas. The goal was to offer a university level course for professionals who work as teachers at the earliest grades of primary school. The analysis of the results, at the end of the course, showed that the objectives proposed were successfully achieved, considering that, of the 14,136 (fourteen thousand, one hundred and thirty-six) effectively enrolled teachers, 13,749 (thirteen thousand, seven hundred and forty-nine) acting teachers were trained at the higher education level. Eighteen (18) Educational Agencies or AFORs were created and the work in the Varginha (MG) Agency gave rise to the research that culminated in this thesis; it was connected to the University Center of Minas Gerais (UNIS). This research had two general objectives: to understand in-service training of optimized Distance Learning tutors through the reflection promoted, through the act of writing and by attainment of auto-heteroevaluative practice and to show the viability of the guiding principles proposed by the Complex Thought in education for in-service training of Distance Learning tutors and the signs of permanence of the transformations which have taken place in the period of this in-service training. The specific objectives were: survey bibliography in relation to the education of Distance Learning tutors; identify the existing relationships between Complex Thought, writing, assessment and education in in-service training of Distance Learning tutors in the Veredas Project of the AFOR/Varginha; show that the in-service training for Distance Learning tutors was focused on encouraging the auto-heteroevaluative process promoted through writing and the practice of the guiding principles of Complex Thought; and verify whether or not the changes that took place in the educational praxis, throughout the training of Distance Learning educational tutors, during the development of the Veredas Project in the AFOR/Varginha, remained after this program ended, using the reports that the tutors drafted during and following the end of this in-service training for this purpose. Considering that, according to the proposals of Complex Thought, the theory and method are two sides of the same movement and have a symbiotic relationship, transmuting without losing their specificity, the methodology used followed these steps: bibliographic survey aimed at a more profound study on the process of professional Distance Learning service education; detecting the existing relationships between the guiding principles-writing-assessment articulated in the formation of the tutoreducator s identity; and requesting that the 56 (fifty-six) tutor-educators who experienced the process of implementation and development of the Veredas Project (2002 to 2005) in the AFOR/Varginha, register their experiences as tutors for the Higher Learning Teacher Education Course Veredas, in the distance learning modality, in writing, focusing on vital aspects of the personal and professional dynamic. From these reports, 10 categories were chosen: learning; assessment; coordination; team experiences; growth; emotion; study; renewal; transformation; and life. Based upon these results it is possible to state that the triad of guiding principles of Complex Thought, the act of writing and the practice of auto-heteroevaluation constitute the cornerstones of the formation of the Distance Learning tutoreducator s identity in service. It is suggested that other studies be done with the goal of increasing the knowledge that has been crystallized here, as well as holding other teacher training courses, using the Veredas model
No ano de 2002, a Secretaria de Estado da Educação de Minas Gerais deu início à implantação do Curso Normal Superior, na modalidade de educação a distância, denominado Veredas. Teve, como objetivo, graduar em nível universitário profissionais que exerciam a docência nas séries iniciais do ensino fundamental. A análise dos resultados, ao final do curso, constatou que os objetivos propostos foram alcançados com êxito, considerando que, dos 14.136 (quatorze mil, cento e trinta e seis) professores efetivamente matriculados, 13.749 (treze mil, setecentos e quarenta e nove) professores em exercício foram habilitados em nível superior. Foram criadas 18 (dezoito) Agências de Formação AFOR e o trabalho da que se situava em Varginha (MG) deu origem à pesquisa que culminou nesta tese; ela estava vinculada ao Centro Universitário de Minas Gerais (UNIS). Foram dois os objetivos gerais desta pesquisa: compreender a formação em serviço do tutor de EaD otimizada pela reflexão promovida, através do ato de escrever e pela consecução da prática auto-heteroavaliativa e mostrar a viabilidade da aplicação dos princípios-guias propostos pelo Pensamento Complexo na formação em serviço do tutoreducador de EaD e os indícios de permanência das transformações ocorridas no período dessa formação em serviço. Os objetivos específicos foram: levantar bibliografia referente à formação do tutor de EaD; Identificar as relações existentes entre o Pensamento Complexo, escrita, avaliação e formação em serviço de tutoreseducadores de EaD no Projeto Veredas da AFOR/Varginha; mostrar que a formação em serviço do tutor de EaD teve como foco o estímulo ao processo auto-heteroavaliativo promovido através da escrita e da prática dos princípios-guias do Pensamento Complexo e verificar se as mudanças ocorridas na práxis pedagógica, ao longo da formação em serviço do tutoreducador de EaD, durante o desenvolvimento do Projeto Veredas na AFOR/Varginha, permaneceram após o término dessa formação, utilizando, para esse fim, os relatos que os tutores elaboraram durante e após o término dessa formação em serviço . Considerando, segundo as propostas do Pensamento Complexo que teoria e método são duas faces de um mesmo movimento, mantendo-se em simbiose, transmutando-se sem, no entanto, perderem sua especificidade, a metodologia utilizada seguiu os seguintes passos: pesquisa bibliográfica com o objetivo de aprofundar os estudos sobre o processo de formação do profissional de EaD em serviço; detectar as relações existentes entre princípios-guiasÛescritaÛavaliação articuladas na formação da identidade do tutoreducador e para tanto, solicitou-se aos 56 (cinquenta e seis) tutoreseducadores que viveram o processo de implantação e desenvolvimento do Projeto Veredas (2002 a 2005) na AFOR/Varginha, que registrassem através da elaboração de um relato escrito, sua experiência como tutor(a) do Curso Superior de Formação de Professores Veredas, na modalidade a distância, enfocando aspectos vitais da dinâmica pessoal e profissional. Dos relatos foram selecionadas 10 categorias: aprendizagem; avaliação; coordenação; convivência em equipe; crescimento; emoção; estudo; renovação; transformação e vida. É possível afirmar que a tríade princípios-guias do Pensamento Complexo, ato de escrever e a prática da auto-heteroavaliação constitui os pilares sustentadores da formação da identidade do tutoreducador de EaD em serviço. Fica a sugestão de que outros estudos sejam feitos com o objetivo de ampliar os conhecimentos que foram aqui cristalizados, bem como a realização de outros cursos de formação de professores, nos moldes do Veredas

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Rouquier, Jean-Baptiste. "Robustesse et émergence dans les systèmes complexes : le modèle des automates cellulaires." Phd thesis, Ecole normale supérieure de lyon - ENS LYON, 2008. http://tel.archives-ouvertes.fr/tel-00354042.

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L'objet de ce travail est de mieux comprendre ce qui se produit lorsque l'on perturbe un système complexe, en utilisant les automates cellulaires comme modèle. Nous nous intéressons principalement à deux perturbations. La première concerne l'écoulement du temps : contrairement au modèle habituel, nous utilisons des mises à jour asynchrones, c'est-à-dire que, à chaque étape, seulement une partie des cellules sont mises à jour. L'autre perturbation concerne la topologie, c'est-à-dire le graphe d'interaction entre les cellules.
Une première partie étudie expérimentalement l'apparition de la percolation dirigée dans les automates cellulaires, notamment dans le cadre du "damage spreading". Le dernier chapitre de cette partie prouve une équivalence entre une classe d'automates cellulaires probabilistes et les automates cellulaires asynchrones.
La seconde partie étudie dans un premier chapitre l'interaction des deux perturbations évoquées: asynchronisme et topologie. Alors que le modèle habituel utilise une grille Zd, nous étudions une grille où certains liens sont temporairement coupés. Puis un second chapitre démontre des propriétés théoriques sur la règles minorité lorsque la topologie est un arbre.
Nous avons dans cette thèse mené à la fois des études expérimentales et des études théoriques. Une préoccupation transversale est la simulation formelle entre modèles. L'enjeu de ces travaux est, à terme, de savoir comment obtenir des systèmes ayant un comportement global prédéfini, ou bien comment rendre robuste à certaines perturbations un système complexe donné.

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41

Ahmad, Shah Masood. "Filling the Structure-Reactivity Gap: in silico approaches to rationalize the design of molecular catalysts." Doctoral thesis, Università degli studi di Padova, 2019. http://hdl.handle.net/11577/3422346.

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The design of molecular catalysts is an ambitious task implying the fundamental issue of relating the molecular structure to the reactivity, i.e., to the catalytic activity. The rationalization of the experimental data is often not straightforward and mechanistic schemes are not transferrable when the conditions of the process are changed or the catalyst is modified even slightly. Computer-aided investigations proved to be a more and more valid support in the last decade, but in most of the cases the aim is limited to investigate in detail the catalytic mechanism of a specific reaction and no general conclusions are drawn that can be used as a guide for designing novel catalysts for the same or analogous processes. In this Project, a computational approach has been set up to investigate the family of organometallic complexes displaying catalytic activity toward [2+2+2] cycloadditions of unsaturated molecules. In a recent book (Transition-metal-mediated aromatic ring construction, John Wiley & Sons, 2013, Chapter 4), Ken Tanaka describes Rhodium mediated [2+2+2] cycloadditions and writes ‘…Although mechanistic aspects of these reactions attract interest, only a few studies have been reported in specific catalysts and substrates…’. Thus this project, abbreviated with the acronym of STREGA (Filling the Structure-Reactivity Gap: in silico approaches to rationalize the design of molecular catalysts), aims at filling the gap between the goldmine of experimental data on this class of very important reactions and their mechanistic rationalization with the purpose of outlining the essential electronic and structural features of the catalyst leading to optimal performance, selectivity, and product yield. In particular, the roles of different metal, different ancillary ligands, different aromatic ligands, and substrates have been accurately investigated; existing data from the literature were also employed for this analysis. Larger polycyclic ligands can in principle host more than a metal center; for example, Cr can be coordinated to the benzene moiety of a rhodium indenyl complex. This might lead to interesting inter metal cooperative effects which might enhance or inhibit the catalytic activity; thus bimetallic catalysts have been considered. The effect of different cooperative metal nuclei was explored changing from Cr to Mo and W, which all belong to Group 6. Finally, the role of the polycyclic aromatic ligand was investigated and found that indeed it is an important factor since it influences rhodium hapticity and consequently its reactivity. All these results allowed to establish a solid structure-activity relationship which is of general validity for rhodium half-sandwich catalysts towards alkyne [2+2+2] cycloadditions and likely is transferrable to analogous Co, Ru, and Ir based fragments.

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42

Belhachmi, Ayoub. "Une méthode implicite pour la construction des modèles géologiques complexes via une interpolation à l'aide des splines et une régularisation basée sur les équations aux dérivées partielles." Electronic Thesis or Diss., Université Côte d'Azur, 2024. http://www.theses.fr/2024COAZ5000.

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La construction d'un géomodèle numérique est une étape clé dans l'étude et l'exploration du sous-sol. Ces modèles sont construits à partir de données sismiques ou de puits, qui forment un ensemble de points de données associés à des valeurs correspondant à leurs âges géologiques. Cette tâche consiste à construire une fonction implicite, également appelée fonction stratigraphique, qui interpole cet ensemble de points de données. Souvent, les données disponibles sont rares et bruitées, ce qui rend cette tâche difficile, principalement pour les réservoirs où les structures géologiques sont complexes avec plusieurs discontinuités. Pour résoudre ce problème, le problème d'interpolation est généralement complété par un terme de régularisation qui impose un comportement régulier de la fonction implicite. Dans cette thèse, nous proposons une nouvelle méthode pour calculer la fonction stratigraphique qui représente les couches géologiques dans des contextes arbitraires. Dans cette méthode, les données sont interpolées par des splines Powell-Sabin C^1 quadratiques par morceaux et la fonction peut être régularisée via de nombreuses énergies de régularisation. La méthode est discrétisée en éléments finis sur un maillage triangulaire conforme aux failles géologiques. Par rapport aux méthodes d'interpolation classiques, l'utilisation de splines quadratiques par morceaux présente deux avantages majeurs. Premièrement, une meilleure approximation des surfaces stratigraphiques présentant de fortes courbures. Deuxièmement, une réduction de la résolution du maillage, tout en générant des surfaces plus lisses et plus régulières.La régularisation de la fonction est la composante la plus difficile de toute approche de modélisation implicite. Souvent, les méthodes classiques produisent des modèles géologiques incohérents, en particulier pour les données présentant de fortes variations d'épaisseur, et des effets de bulles sont généralement observés. Pour résoudre ce problème, nous introduisons deux nouvelles énergies de régularisation liées à deux EDPs fondamentales, sous leur forme générale avec des coefficients variants spatialement. Ces EDPs sont l'équation de diffusion anisotrope et l'équation de flexion d'une plaque mince anisotrope. Dans la première approche, le tenseur de diffusion est introduit et adapté de manière itérative aux variations et à l'anisotropie des données. Dans la seconde, le tenseur de rigidité est adapté de manière itérative aux variations et à l'anisotropie des données. Nous démontrons l'efficacité des méthodes proposées en 2D, spécifiquement sur des coupes transversales de modèles géologiques avec des réseaux de failles complexes et des couches géologiques présentant des variations d'épaisseur
The construction of a geological numerical model is a key step in the study and exploration of the subsurface. These models are constructed from seismic or well data, which consist of data points associated with values corresponding to their geological ages. This task involves constructing an implicit function, known also as stratigraphic function, which interpolates this set of data points. Often the available data are sparse and noisy, which makes this task difficult, mainly for reservoirs where the geological structures are complex with distinct discontinuities and unconformities. To address this, the interpolation problem is typically supplemented with a regularization term that enforces a regular behaviour of the implicit function. In this thesis, we propose a new method to compute the stratigraphic function that represents geological layers in arbitrary settings. In this method, the data are interpolated by piecewise quadratic C^1 Powell-Sabin splines and the function can be regularized via many regularization energies. The method is discretized in finite elements on a triangular mesh conforming to the geological faults. Compared to classical interpolation methods, the use of piecewise quadratic splines has two major advantages. First, a better handling of stratigraphic surfaces with strong curvatures. Second, a reduction in mesh resolution, while generating surfaces of higher smoothness and regularity.The regularization of the function is the most difficult component of any implicit modeling approach. Often, classical methods produce inconsistent geological models, in particular for data with high thickness variation, and bubble effects are generally observed. To handle this problem, we introduce two new regularization energies that are linked to two fundamental PDEs, in their general form with spatially varying coefficients. These PDEs are the anisotropic diffusion equation and the equation that describes the bending of an anisotropic thin plate. In the first approach, the diffusion tensor is introduced and iteratively adapted to the variations and anisotropy of the data. In the second, the rigidity tensor is iteratively adapted to the variations and anisotropy in the data. We demonstrate the effectiveness of the proposed methods in 2D, specifically on cross-sections of geological models with complex fault networks and thickness variations in the layers

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43

Silva, Mait? Medeiros de Santana e. "S?ntese e caracteriza??o do Molibdato de Estr?ncio obtido a partir do m?todo de complexa??o combinado EDTA/Citrato para degrada??o fotocatal?tica de corante da ind?stria t?xtil." PROGRAMA DE P?S-GRADUA??O EM ENGENHARIA QU?MICA, 2016. https://repositorio.ufrn.br/jspui/handle/123456789/21877.

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)
Este trabalho descreve o planejamento experimental 2? com triplicata no ponto central para produ??o do molibdato de estr?ncio (SrMoO4) atrav?s do m?todo de complexa??o combinado EDTA/Citrato onde investigou-se a influ?ncia do pH (6, 7,5 e 9), tempo de calcina??o (3, 4 e 5h) e taxa de aquecimento (5, 7 e 10?C.min-1) em alguns de seus par?metros qu?micos e f?sicos. Com base na curva de termogravim?trica os p?s de SrMoO4 foram calcinados a 650?C.Os materiais sintetizados foram caracterizados por TG/DSC, DRX, EDX, MEV e ERD. Os par?metros de rede da estrutura cristalina foram obtidos com base no m?todo de refinamento Rietveld. Todos os padr?es de DRX foram indexados segundo a ficha JCPDS 01-085-0586, com estrutura tetragonal e grupo espacial I41/a e o par?metro residual do refinamento da estrutura variou entre 1,035 a 1,292, n?o sendo identificadas fases secund?rias e impurezas. Constatou-se a exist?ncia de diferen?as entre as intensidades relativas m?dias dos picos de difra??o de raios-x. Atrav?s de ferramentas estat?sticas, concluiu-se que a taxa de aquecimento foi a vari?vel independente que demonstrou maior influ?ncia nessa diferen?a. As analises de EDX mostraram a presen?a de desvios entre a composi??o te?rica e experimental para os elementos estr?ncio e molibd?nio; o desvio percentual variou de 0,027 a 3,67% em fun??o das condi??es de s?ntese. De acordo com as micrografias obtidas por MEV, os p?s sintetizados s?o compostos de aglomerados de part?culas, com morfologia esf?ricas irregulares e bipiramidais. De acordo com a an?lise do planejamento experimental, tendo como vari?vel dependente a energia de bandgap, os menores valores obtidos (4,18 e 4,17 eV para pH 6 e 9, respectivamente) foram as amostras calcinadas por 3h com taxa de aquecimento igual a 10?C.min-1 em compara??o aos materiais calcinados nas demais condi??es de s?nteses e os modelos estat?sticos gerados se mostraram capazes de descrever os fen?menos observados. Testes explorat?rios na fotodegrada??o da solu??o sint?tica do corante azul de metileno utilizando o material com Egap de 4,17 eV indicam que o p? testado apresenta influ?ncia na diminui??o da concentra??o do corante para os testes realizados em pH 2 e 5 obtendo aproximadamente 95% e 24% de convers?o respectivamente, e para os teste em pH 9 observou-se que a fot?lise direta ? mais efetiva na redu??o da concentra??o do corante alcan?ando em torno 67% de convers?o, por?m o processo reacional necessita ser mais estudado para melhor compreens?o dos resultados.
This work describes the 2? experimental design with center point in triplicate for the production of strontium molybdate (SrMoO4) through complexation combined Citrate/EDTA method where investigated the influence of pH (6, 7,5 and 9), time calcination (3, 4 and 5 h) and heating rate (5, 7 and 10?C min-1) in some of its chemical and physical parameters. Based on thermogravimetric curve of SrMoO4 powders were calcined at 650?C. The synthesized materials were characterized by TG/DSC, XRD, EDX, SEM and ERD. The lattice parameters of the crystal structure were obtained from the Rietveld refinement method. All the XRD patterns were indexed according to JCPDS 01-085-0586 record with tetragonal structure and space group I41/a and the residual parameter structure refinement ranged from 1.035 to 1.292, secondary phases and impurities not being identified. It was found that there are differences between the average relative intensities of the diffraction peaks of X-rays. Using statistical tools, it was found that the rate of heating was the independent variable showed the greatest influence on this difference. The EDX analysis showed the presence of deviations between the theoretical and experimental composition for strontium and molybdenum components; the percentage deviation ranged from 0.027 to 3.67% depending on the conditions of synthesis. According to the SEM micrographs, the synthesized powders are composed of agglomerates of particles with irregular and spherical morphology bipiramidal. According to the analysis of the experimental design, with the dependent variable bandgap energy, the lowest values (4.18 and 4.17 eV to pH 6 and 9, respectively) were the samples calcined for 3 hours at the same heating rate 10 C min-1 compared to the calcined material in other conditions of synthesis and the statistical models generated have been shown to describe the observed phenomena. Exploratory testing photodegradation of the synthetic solution of methylene blue dye using the material bandgap of 4.17 eV indicate that the tested powder has influence on the reduction of dye concentration for tests carried out in pH 2 and 5 getting approximately 95% and 24 % conversion respectively, and the test at pH 9 it was noted that direct photolysis is more effective in reducing the dye concentration reached around 67% conversion, but the reaction process needs more study to better understand the results.

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44

Nagy, Péter. "Formation and Decomposition of Platinum–Thallium Bond, Kinetics and Mechanism. Structural Characterization of Some Metal Cyanides in the Solid State." Doctoral thesis, KTH, Chemistry, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3803.

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The kinetic and mechanistic features of a new series ofplatinum-thallium cyano compounds containing a direct andunsupported by ligands metal-metal bond have been studied insolution, using standard mixandmeasurespectrophotometric technique and stoppedflow method.These reactions are interpreted as oxidative addition of the cspecies to the square planar Pt(CN)₄^2-complex. Each of these processes was found to befirst-order in Pt(CN)₄^2-, the corresponding TI^IIIcomplex and a cyanide ion donating species whichacts as a catalyst. Both di- and trinuclear complexes werestudied, and the kinetically significant thallium complexes intheir formation and the catalytically active cyanide sourcesare as follows: [(CN)₅PtTl(CN)₃]^3-: Tl(CN)₄(alkaline region), Tl(CN)₃(slightly acidic region) and CN; [(CN)₅PtTl(CN)]: Tl(CN)₂⁺and Tl(CN)₂⁺; [(CN)₅PtTlPt(CN)₅]^3-: [(CN)₅PtTl(CN)]and HCN. Appropriatemechanisms were postulated for the overall reactions in allcases, which include i) metalmetal bond formation stepand ii) coordination of an axial cyanide ion to the platinumcenter. Two experimentally indistinguishable kinetic modelswere proposed for the formation of the dinuclear complexeswhich are different in the sequence of the two steps. In thecase of the trinuclear complex, experimental evidence isavailable to exclude one of the alternative reaction paths, andit was proven that the metalmetal bond formation precedesthe axial cyanide coordination.

The cyanide ligands coordinated to TI^IIIin the PtTl complexes could be replacedsuccessfully with aminopolycarboxylates e.g.: mimda^2-, nta^3-, edta^4-. The [(CN)₅PtTl(edta)]^4-complex, with a direct metalmetal bond hasbeen prepared in solution by two different reactions: a)dissolution of [(CN)₅PtTl](s) in an aqueous solution of edta, b)directly from Pt(CN)₄^2-and Tl(edta)(CN)^2-. The decomposition reaction is greatlyaccelerated by cyanide and significantly inhibited by edta. Itproceeds through the [(CN)₅PtTl(CN)₃]^3-intermediate. The formation of [(CN)₅PtTl(edta)]^4-can proceed via two different pathways dependingon the ratio of the cyanide to the edta ligand concentrations.Thedirect pathat excess of edta means theformation of intermediate[(CN)4Pt···Tl(CN)(edta)]^4-, followed by a release of the cyanide from theTlcentre followed by coordination of a cyanide from thebulk to the Ptcentre of the intermediate. Theindirect pathdominates in the absence of extraedta and the formation of the PtTl bond occours betweenPt(CN)₄^2-and Tl(CN)4.

Homoligand MTl(CN)₄(M = Tl^I, K, Na) and, for the first time, Tl(CN)₃species have been synthesized in the solid stateand their structures solved by single crystal Xraydiffraction method. Interesting redox processes have been foundbetween TI^IIIand CNin nonaqueous solution and in Tl₂O₃-CNaqueous suspension. In the crystal structureof Tl(CN)₃·H₂O, the thallium(III) ion has a trigonal bypiramidalcoordination geometry with three cyanides in the trigonalplane, while an oxygen atom of the water molecule and anitrogen atom from a cyanide ligand attached to a neighboringthallium complex, form a linear OTlN fragment.Cyanide ligand bridges thallium units forming an infinitezigzag chain structure. Among the thallium(III) tetracyanocompounds, the isostructural M[Tl(CN)₄](M = Tl and K) and Na[Tl(CN)₄]·3H₂O crystallize in different crystal systems, but thethallium(III) ion has in all cases the same tetrahedralgeometry in the [Tl(CN)₄]unit.

Three adducts of mercury(II) (isoelectronic with TI^III) (K₂PtHg(CN)₆·2H₂O, Na₂PdHg(CN)₆·2H₂O and K₂NiHg(CN)₆·2H₂O) have been prepared from Hg(CN)₂and square planar transition metal cyanides M^II(CN)₄^2-and their structure have been studied by singlecrystal Xray diffraction, XPS and Raman spectroscopy inthe solid state. The structure of (K₂PtHg(CN)₆·2H₂O consists of strictly linear one dimensional wireswith Pt^IIand Hg^IIcenters located alternately, d_HgPt= 3.460 Å. The structure of Na₂PdHg(CN)₆·2H₂O and K₂NiHg(CN)₆·2H₂O can be considered as double salts, the lack ofheterometallophilic interaction between both the Hg^IIand Pd^IIatoms, d_HgPd= 4.92 Å, and Hg^IIand Ni^IIatoms, d_NiPd= 4.60 Å, seems obvious. Electronbinding energy values of the metallic centers measured by XPSshow that there is no electron transfer between the metal ionsin all three adducts. In solution, experimental findingsclearly indicate the lack of metalmetal bond formation inall studied Hg^IICN^-M^II(CN)4^2-systems (M = Pt, Pd and Ni). It is in contrary tothe platinumthallium bonded cyanides.

KEYWORDS:metalmetal bond, platinum, thallium,kinetics, mechanism, stopped flow, oxidative addition, cyanocomplexes, edta, redox reaction, metal cyanides, Xraydiffraction, Raman, NMR, mercury, palladium, nickel, onedimensional wire

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45

Shi, Dingding. "Defining the Roles of p300/CBP (CREB Binding Protein) and S5a in p53 Polyubiquitination, Degradation and DNA Damage Responses: A Dissertation." eScholarship@UMMS, 2010. https://escholarship.umassmed.edu/gsbs_diss/452.

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p53, known as the “guardian of the genome”, is the most well-characterized tumor suppressor gene. The central role of p53 is to prevent genome instability. p53 is the central node in an incredibly elaborate genome defense network for receiving various input stress signals and controlling diverse cellular responses. The final output of this network is determined not only by the p53 protein itself, but also by other p53 cooperating proteins. p300 and CBP (CREB-Binding Protein) act as multifunctional regulators of p53 via acetylase and ubiquitin ligase activities. Prior work in vitro has shown that the N-terminal 595 aa of p300 encode both generic ubiquitin ligase (E3) and p53-directed E4 functions. Analysis of p300 or CBP-deficient cells revealed that both coactivators were required for endogenous p53 polyubiquitination and the normally rapid turnover of p53 in unstressed cells. Unexpectedly, p300/CBP ubiquitin ligase activities were absent in nuclear extracts and exclusively cytoplasmic. In the nucleus, CBP and p300 exhibited differential regulation of p53 gene target expression, C-terminal acetylation, and biologic response after DNA damage. p300 activated, and CBP repressed, PUMA expression, correlating with activating acetylation of p53 C-terminal lysines by p300, and a repressive acetylation of p53 lysine-320 induced by CBP. Consistent with their gene expression effects, CBP deficiency augmented, and p300 deficiency blocked, apoptosis after doxorubicin treatment. Subcellular compartmentalization of p300/CBP’s ubiquitination and transcription activities reconciles seemingly opposed functions—cytoplasmic p300/CBP E4 activities ubiquitinate and destabilize p53, while nuclear p300/CBP direct p53 acetylation, target gene activation, and biological outcome after genotoxic stress. p53 is a prominent tumor suppressor gene and it is mutated in more than 50% of human tumors. Reactivation of endogenous p53 is one therapeutic avenue to stop cancer cell growth. In this thesis, we have identified S5as a critical regulator of p53 degradation and activity. S5a is a non-ATPase subunit in the 19S regulatory particle of the 26S proteasome. Our preliminary data indicates that S5a is required for p53 instability and is a negative regulator of p53 tranactivation. As a negative regulator of p53, S5a may therefore also represent a new target for cancer drug development against tumors that specifically maintain wild type p53.

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46

Ghosh, Sampa. "Quadratic Optical Nonlinearity And Geometry Of 1:1 Electron Donor Acceptor Complexes In Solution." Thesis, 2008. https://etd.iisc.ac.in/handle/2005/711.

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The knowledge of geometry of molecular complexes formed via molecular association in solution through weak interactions is always important to understand the origin of stability and function of an array of molecules, supramolecular assemblies, and macromolecular networks. Simple 1:1 molecular complexes are very useful in this regard as they provide a model to understand both the nature of these interactions and their structural implications. Several weak noncovalent forces from long range (van der Waal’s, electrostatic, induction, dispersion) to short range (charge transfer) govern the geometry, that is, relative orientation of the two molecules in such a complex. On one hand, we find 1:1 electron donor acceptor (EDA) complexes such as naphthalene-tetracyanobenzene, hexamethylbenzene-chloranil etc. which stack parallel or in slipped parallel geometry in their crystals. On the other, benzene dimer has been found to stabilize in T shaped geometry in all its three physical states. In this thesis, I focus on 1:1 EDA complexes in solution. A good volume of literature is available which deals with the optical studies on the formation of such complexes. It has been suggested that the nature of the intermolecular interactions stabilizing these complexes in the gas phase or in their crystals is modified by the presence of solvent-solute interactions in solution thus bringing in difference in the solution geometry. However, the existing experimental techniques, both optical and magnetic, are unable to determine the exact geometries of 1:1 EDA complexes in solution. This opens an opportunity to probe their geometry in solution. The quadratic nonlinearity or first hyperpolarizability (β) of a molecule is a measure of the change in dipole moment (or polarization) in the second order of the applied electrical field and thus has a purely electronic origin. It is a tensorial property and can be resolved in components along the three dimensions. The number of β components and the nonlinear optical anisotropies in a typical donor-acceptor type dipolar molecule, defined as (equation) (where1, 2, 3 axes define the molecular frame, 1 being the direction along the principal axis of symmetry and pointing from the acceptor toward the donor), are determined by the symmetry /structure of the molecule. It has been shown theoretically that the 1:1 EDA complexes possess large hyperpolarizabilities. In the case of pNA dimers calculation revealed that the geometry of the dimer and its symmetry is important for obtaining the correct estimate of β from its tensorial components. Therefore, it should be possible to use the values of tensorial β components to construct the unknown geometry of such complexes. Experimentally macroscopic depolarization ratios (D and D′) in the laboratory fixed frame (XYZ, X being the direction of polarization and Z the direction of propagation of the incident light), are measured from the polarization resolved intensities of second harmonic scattering from molecules in solution using the hyper-Rayleigh scattering technique. The depolarization ratios are correlated to the anisotropy parameters, u and v through a co-ordinate transformation. In this thesis I, have first, characterized the quadratic nonlinear optical property of a variety of 1:1 electron donor acceptor complexes and used the values of u and v obtained from depolarized hyper-Rayleigh scattering to deduce their geometry in solution. Chapter 1 provides an introduction to the 1:1 electron donor acceptor complexes, their relevance to chemistry and biology. It also contains an introduction to nonlinear optical processes in molecules. The objective of the present work and scope of the investigation carried out in this thesis is presented in this chapter. Chapter 2 describes the details of the experimental polarization resolved HRS technique. The geometrical model adopted for the analysis of the HRS data has also been introduced and the method of analysis has been described in detail in this chapter. Chapter 3 presents the measurement of β values of two series of 1:1 EDA complexes of variously substituted methylbenzenes donors with tetrachloro-p-benzoquinone (CHL) and dicyanodichloro-p-benzoquinone (DDQ) acceptors at 1064 nm. In agreement with recent theoretical results we find large first hyperpolarizabilities for these complexes. The β values are greater than that of the typical push-pull molecule p-nitroaniline (pNA). We also find that in general β decreases with decrease in the donor strength. Chapter 4 presents the β values for the two series of EDA complexes of CHL and DDQ acceptors at 1907 nm. The values of β are less in magnitude at 1907 nm than that at 1064 nm which is due to the dispersion effect in β. In Chapter 5 and 6, it is described how depolarized hyper-Rayleigh scattering can be utilized to probe geometries of 1:1 complexes in solution. Chapter 5 concentrates mainly on 1:1 EDA complexes of CHL and DDQ and TCNB (tetracyanobenzene), while chapter 6 contains examples of other 1:1 molecular complexes where the noncovalent interactions are much weaker, such as in benzene-naphthalene, benzene-methoxybenzene, benzene-hexafluorobenzene and benzene-chlorobenzene pairs. We find the geometry of 1:1 EDA complexes in solution in terms of tilt angle (θ) and twist angle (ϕ) between the donor and acceptor pairs. The angle θ varies from 29°-47° for different pairs of EDA complexes, while ϕ varies within 34° and 38°. We find that the geometry of 1:1 EDA complexes in solution is different (twisted and tilted cofacial and twisted ‘V’) from those in the crystalline or gaseous states (cofacial), if known. We find that both benzene-naphthalene and benzene-chlorobenzene pairs assume twisted ‘T’ shape geometry with θ = 82° and 85°, respectively, and φ = 38°, while benzene-hexafluorobenzene assumes a twisted ‘V’ shape. A strong solvent effect is seen in the geometry of the benzene- methoxybenzene complex. The tilt angle is 55° when chloroform is used as a solvent and it is 82° without chloroform. Chapter 7 is the concluding chapter where the main work done in this thesis is summarized and future directions are presented.

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47

Ghosh, Sampa. "Quadratic Optical Nonlinearity And Geometry Of 1:1 Electron Donor Acceptor Complexes In Solution." Thesis, 2008. http://hdl.handle.net/2005/711.

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Abstract:

The knowledge of geometry of molecular complexes formed via molecular association in solution through weak interactions is always important to understand the origin of stability and function of an array of molecules, supramolecular assemblies, and macromolecular networks. Simple 1:1 molecular complexes are very useful in this regard as they provide a model to understand both the nature of these interactions and their structural implications. Several weak noncovalent forces from long range (van der Waal’s, electrostatic, induction, dispersion) to short range (charge transfer) govern the geometry, that is, relative orientation of the two molecules in such a complex. On one hand, we find 1:1 electron donor acceptor (EDA) complexes such as naphthalene-tetracyanobenzene, hexamethylbenzene-chloranil etc. which stack parallel or in slipped parallel geometry in their crystals. On the other, benzene dimer has been found to stabilize in T shaped geometry in all its three physical states. In this thesis, I focus on 1:1 EDA complexes in solution. A good volume of literature is available which deals with the optical studies on the formation of such complexes. It has been suggested that the nature of the intermolecular interactions stabilizing these complexes in the gas phase or in their crystals is modified by the presence of solvent-solute interactions in solution thus bringing in difference in the solution geometry. However, the existing experimental techniques, both optical and magnetic, are unable to determine the exact geometries of 1:1 EDA complexes in solution. This opens an opportunity to probe their geometry in solution. The quadratic nonlinearity or first hyperpolarizability (β) of a molecule is a measure of the change in dipole moment (or polarization) in the second order of the applied electrical field and thus has a purely electronic origin. It is a tensorial property and can be resolved in components along the three dimensions. The number of β components and the nonlinear optical anisotropies in a typical donor-acceptor type dipolar molecule, defined as (equation) (where1, 2, 3 axes define the molecular frame, 1 being the direction along the principal axis of symmetry and pointing from the acceptor toward the donor), are determined by the symmetry /structure of the molecule. It has been shown theoretically that the 1:1 EDA complexes possess large hyperpolarizabilities. In the case of pNA dimers calculation revealed that the geometry of the dimer and its symmetry is important for obtaining the correct estimate of β from its tensorial components. Therefore, it should be possible to use the values of tensorial β components to construct the unknown geometry of such complexes. Experimentally macroscopic depolarization ratios (D and D′) in the laboratory fixed frame (XYZ, X being the direction of polarization and Z the direction of propagation of the incident light), are measured from the polarization resolved intensities of second harmonic scattering from molecules in solution using the hyper-Rayleigh scattering technique. The depolarization ratios are correlated to the anisotropy parameters, u and v through a co-ordinate transformation. In this thesis I, have first, characterized the quadratic nonlinear optical property of a variety of 1:1 electron donor acceptor complexes and used the values of u and v obtained from depolarized hyper-Rayleigh scattering to deduce their geometry in solution. Chapter 1 provides an introduction to the 1:1 electron donor acceptor complexes, their relevance to chemistry and biology. It also contains an introduction to nonlinear optical processes in molecules. The objective of the present work and scope of the investigation carried out in this thesis is presented in this chapter. Chapter 2 describes the details of the experimental polarization resolved HRS technique. The geometrical model adopted for the analysis of the HRS data has also been introduced and the method of analysis has been described in detail in this chapter. Chapter 3 presents the measurement of β values of two series of 1:1 EDA complexes of variously substituted methylbenzenes donors with tetrachloro-p-benzoquinone (CHL) and dicyanodichloro-p-benzoquinone (DDQ) acceptors at 1064 nm. In agreement with recent theoretical results we find large first hyperpolarizabilities for these complexes. The β values are greater than that of the typical push-pull molecule p-nitroaniline (pNA). We also find that in general β decreases with decrease in the donor strength. Chapter 4 presents the β values for the two series of EDA complexes of CHL and DDQ acceptors at 1907 nm. The values of β are less in magnitude at 1907 nm than that at 1064 nm which is due to the dispersion effect in β. In Chapter 5 and 6, it is described how depolarized hyper-Rayleigh scattering can be utilized to probe geometries of 1:1 complexes in solution. Chapter 5 concentrates mainly on 1:1 EDA complexes of CHL and DDQ and TCNB (tetracyanobenzene), while chapter 6 contains examples of other 1:1 molecular complexes where the noncovalent interactions are much weaker, such as in benzene-naphthalene, benzene-methoxybenzene, benzene-hexafluorobenzene and benzene-chlorobenzene pairs. We find the geometry of 1:1 EDA complexes in solution in terms of tilt angle (θ) and twist angle (ϕ) between the donor and acceptor pairs. The angle θ varies from 29°-47° for different pairs of EDA complexes, while ϕ varies within 34° and 38°. We find that the geometry of 1:1 EDA complexes in solution is different (twisted and tilted cofacial and twisted ‘V’) from those in the crystalline or gaseous states (cofacial), if known. We find that both benzene-naphthalene and benzene-chlorobenzene pairs assume twisted ‘T’ shape geometry with θ = 82° and 85°, respectively, and φ = 38°, while benzene-hexafluorobenzene assumes a twisted ‘V’ shape. A strong solvent effect is seen in the geometry of the benzene- methoxybenzene complex. The tilt angle is 55° when chloroform is used as a solvent and it is 82° without chloroform. Chapter 7 is the concluding chapter where the main work done in this thesis is summarized and future directions are presented.

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48

Li, JUN. "A SENSOR-BASED APPROACH TO MONITORING WEB SERVICE." Thesis, 2008. http://hdl.handle.net/1974/1581.

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Abstract:

As the use of Web expands, Web Service is gradually becoming the basic system infrastructure. However, as it matures and a large number of Web Service becomes available, the focus will shift from service development to service management. One key component in management systems is monitoring. The growing complexity of Web Service platforms and their dynamically varying workloads make manually monitoring them a demanding task. Therefore monitoring tools are required to support the management efforts. Our approach, Web Service Monitoring System (WSMS), utilizes Autonomic Computing technology to monitor Web Service for an automated manager. WSMS correlates lower level events into a meaningful diagnosed symptom which provides higher level information for problem determination. It also gains the ability to take autonomic actions and solve the original problem using corrective actions. In this thesis, a complete design of WSMS is presented along with a practical implementation showing viability and proof of concept of WSMS.
Thesis (Master, Computing) -- Queen's University, 2008-11-12 16:20:13.738

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49

PALI, Nefton. "Structures différentielles en géométrie complexe et presque complexe." Phd thesis, 2004. http://tel.archives-ouvertes.fr/tel-00007104.

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Abstract:

Nous généralisons au contexte des faisceaux analytiques cohérents un résultat classique de Koszul-Malgrange concernant l'intégrabilité des connexions de type $(0,1)$ sur un fibré vectoriel complexe $(\cal C)^(\infty)$ au dessus d'une variété complexe. En introduisant la notion de faisceau $\bar(\partial)$-cohérent, qui est une notion qui vit dans le contexte $(\cal C)^(\infty)$, nous montrons l'existence d'une équivalence (exacte) entre la catégorie des faisceaux analytiques cohérents et la catégorie des faisceaux $\bar(\partial)$-cohérents. L'application principale de cette caractérisation est une méthode (la $\bar(\partial)$-stabilité) qui permet de trouver des structures analytiques lesquelles sont obtenues par déformation $\ci$ d'autres structures analytiques. En suite nous conjecturons, comme dans le cas analytique complexe, que la notion de plurisousharmonicité pour une fonction $u$ sur une variété presque complexe est équivalente à la positivité du $(1,1)$-courant $i\partial\bar(\partial)u$. Nous montrons la nécessité de la positivité de ce courant. Nous montrons aussi la suffisance de la positivité dans le cas particulier d'une fonction semi-continue supérieurement et continue en dehors du lieu ou elle vaut $-\infty$.

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50

Kulesza, Caroline Ann. "Adenovirus E1A requires the yeast SAGA histone acetyltransferase complex and associates with SAGA component Tra1 in vivo /." 2001. http://wwwlib.umi.com/dissertations/fullcit/3003890.

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Dissertations / Theses on the topic 'Complexe EDA'

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