The ignition process is a critical consideration for combustion devices. External energy transfer to the combustor is required for ignition in common combustion systems. There are many ways to deposit energy into the flow but a standard method is a spark discharge because it is simple, compact, and reliable. Sparks can be categorized as either inductive or capacitive sparks that use a coil or an electrical resonance circuit with capacitor, respectively, to amplify the voltage. The creation of a successful ignition event depends on the spark energy deposited into the flow, the initial composition, pressure, temperature, turbulence level of flow etc. The deposited energy by the spark into the flow is critical for estimation of initial energy available for ignition of the mixture. Therefore, the electrical characteristics of the sparks were investigated under various flow conditions. Then measurements of deposited energy into the flow were conducted using a very accurate experimental procedure that was developed in this research. The results showed considerable electric energy losses to the electrodes for the relatively long, inductive sparks. However, the short, capacitive spark deposits electric energy into the flow with minimal loss (above 90% deposition efficiency). In addition, the characteristics of inductive spark are affected by flow velocity and by the existence of a flame. However, variations in the flow conditions do not affect the characteristics of the capacitive spark such as voltage-current time trace and energy deposition efficiency. Two ignition systems using above mentioned two spark types were developed. First, the capacitive spark energy was directly deposited into the premixed flow. Most researchers have not concentrated on the early initiation process but on the flame growth. Therefore, the generated kernel formed by the energy deposition was observed and characterized using optical methods, immediately following the spark. In addition, the mixing effect for this ignition kernel with surrounding gas was simulated using a numerical method. Based on the time trace of the OH* chemiluminescence, the reaction starts with the discharge and it is continuous until combustion begins. This means that in the presence of a high density spark in premixed flow, there exists no traditional delay as defined by other researchers for auto ignition. A simple Radical Jet Generator (RJG) was developed that is able to ignite and stabilize a flame in a high-speed flow. The inductive spark initiates the combustion in the RJG chamber. The RJG then injects the partially-burned products carrying large amounts of heat and radicals into a rapidly moving flammable main stream. Then it ignites and stabilizes a flame. The RJG requires low levels of electrical power as long as the flow velocity is relatively low since most of the radicals are produced by the incomplete combustion in its chamber. The importance of radicals was analyzed by RJG experiments and numerical methods. The reaction zone for RJG using a rich mixture was located both inside and outside of the RJG chamber. Therefore, the RJG using a rich mixture performed better in the ignition and stabilization of combustion in the main flow. According to an analysis using the CHEMKIM simulation software combined with the San Diego chemical mechanism, the RJG jet resulting from a rich mixture contains more radicals and intermediates than that produced by a lean mixture for the same sensible enthalpy. In addition, the burned gas contains less radicals and intermediates than the partially burned gas. If the RJG is operating with a high speed main flow, the flow rate through the RJG chamber must be increased to allow the radical jet to penetrate well into the rapid flow due to their higher injection velocity. Unfortunately, this leads to unsteady combustion in the RJG, which results in the pulsation of the radical jet. This reduces the number of radicals injected into the main flow. To investigate this operating condition, special attention was focused on four possible factors: unburned reactant pockets caused by motion of the spark channel, spark frequency, flame propagation speed and ignition delay. It was shown that the unsteadiness is affected by the flame speed and ignition delay because the frequency of pulsation in the chamber is highly dependent on the equivalence ratio. In addition, the interaction between the RJG operation and the combustion dynamics in the main combustor was documented. The acoustic pressure oscillations in the main combustor were suppressed when the RJG jet was turned on because the reaction region is relocated by the operation of the RJG.

In this study, ethyl methacrylate was polymerized by free radical polymerization at 600C, 700C, 800C at open atmosphere / atom transfer radical polymerization, (ATRP), at 800C in vacuum and in gamma irradiation in vacuum. The polymer obtained was white, hard material. The kinetic curves for free radical polymerization and ATRP by gamma radiation were S-type. However, the curve for polymerization by gamma irradiation raises more smoothly. For ATRP by thermal initiation gives a lineer change of conversion with time. It was observed that the molecular weight can be controlled and low molecular weight polymer could be obtained by ATRP method. The characterization of polymers were made by FTIR, DSC, 1H and 13C NMR techniques.

Notre thèse vise à montrer que les résistants au changement peuvent être considérés comme des parties prenantes à part entière du processus d’apprentissage organisationnel, notamment lorsqu’on considère les apports pour l’entreprise de leurs réactions de défense de l’identité. Pour atteindre cet objectif, nous suivons une démarche qualitative du type théorisation ancrée-nuancée (Paillé, 1996). Notre recherche associe donc un cadre conceptuel préliminaire à une étude empirique inductive pour élaborer un modèle schématisant les phénomènes associés aux apports des comportements de résistance. Notre revue de littérature permet d’abord d’envisager le changement à travers son impact sur l’identité organisationnelle (Corley et Gioia, 2004). Ensuite, nous prenons en compte les capacités des résistances à transformer significativement l’entreprise dans le temps (Courpasson et al., 2012). Enfin, nous développons une approche cognitive du changement qui nous amène à considérer les résistants pour leur participation à la diversité des points de vue à l’intérieur de l’entreprise. Issues d’un journal de bord, de 42 entretiens semi-directifs et d’une analyse documentaire, nos données permettent de comprendre comment le changement s’enracine progressivement dans l’organisation et comment les résistants participent à ce processus. Ainsi, notre analyse inductive aboutit à un modèle à deux niveaux. Le premier décrit le changement organisationnel radical à travers un cheminement par trois phases d’initiation, d’accentuation et d’enracinement. Nous nous intéressons notamment aux influences de l’identité organisationnelle, de ses dissonances avec des logiques identitaires alternatives et de l’implication des salariés dans l’ajustement du changement pour montrer comment ce cheminement aboutit à l’émergence d’apprentissages individuels et organisationnels associés à une gouvernance cognitive. Le deuxième niveau de modélisation se focalise sur les rôles des résistants dans ce cheminement. Il montre que les résistants sont des parties prenantes des étapes clés du changement et qu’ils permettent à l’entreprise d’évoluer progressivement vers l’idéal-type d’organisation apprenante. Nous proposons également une typologie de résistants (Oubliés, Suiveurs, Salariés émergents, Nouveaux rebelles) qui permet d’aborder la diversité des implications positives des comportements de résistance. / Our thesis aims to demonstrate that resistant individuals can be integrated as real stakeholders of the organizational learning process. This integration is possible when the consequences of their identity defense mechanisms for the organization are taken into account. To achieve this goal, our qualitative study follows a semi-grounded theory approach. This approach combines a preliminary theoretical framework and inductive empirical data to elaborate a model showing some positive contributions of resistance. Our research first addresses change through its impact on organizational identity (Corley & Gioia, 2004). Then, it considers how resisting activities can achieve significant organizational change (Courpasson et al., 2012). Finally, it develops a cognitive approach of change that brings us to consider resisting behaviors for their participation in the diversity of points of view inside the organization. Based on logbook extractions, 42 semi-directive interviews and a documentary analysis, our data provide a better understanding of how change takes root in the organization and how resistant individuals participate in this process. Thus, this inductive study results in a two-level model. The first level shows radical organizational change as a three-steps process: initiation, accentuation and rooting. In particular, we focus on organizational identity, its dissonances with alternative identity-related logics and the employees’ implication in the adjustment of change. This process results in the emergence of individual and organizational learning associated to a cognitive governance. The second level details the roles of the resistant individuals in this process. It shows that they can be real stakeholders of the key stages of change. In so doing, they allow the company to evolve towards the ideal of learning organization. We also propose a typology of resistant individuals (Forgotten, Followers, Emergent, New rebels), which allows us to develop some positive implications of resistance.

This article studies the relationship between trafficking for sexual exploitation and prostitution. The study of this relationship will focus on the positions advocating the criminalization of prostitution and/or conduct consumer / customer. This analysis leads us to analyze, first, the crime of trafficking in persons. In this line, we will discuss the issue on the legal right; and its characteristic as complex crime comprising various means, behaviors and purposes. Second, we will approach the four kinds of legislative policies prostitution: reglamentarism, prohibitionist, abolitionist and regulationism. The critical study of these models will allow us to outline a tentative conclusion on the criminalization of prostitution and consumer behavior / customer. / El presente artículo estudia la relación entre la trata con fines de explotación sexual y la prostitución. El estudio de esta relación se focalizará en las posturas que abogan por la criminalización de la prostitución y/o de la conducta del consumidor/cliente. Dicho análisis nos llevará a analizar, en primer lugar, el tipo penal de trata de personas. En esta línea, expondremos la problemática sobre el bien jurídico; y su característica como delito complejo integrado por distintos medios, comportamientos y fines. En segundo lugar, nos aproximaremos a las cuatro clases de políticas legislativas en materia de prostitución: reglamentarismo, prohibicionismo, abolicionismo y regulacionismo. El estudio crítico de estos modelos nos permitirá esbozar una conclusión provisional sobre la criminalización de la prostitución y de la conducta del consumidor/cliente.

Submitted by WESLEY JUSTINO MAGNABOSCO null (wesley.urologia@hotmail.com) on 2016-04-25T10:30:06Z No. of bitstreams: 1 Doutorado_versao final.pdf: 1346455 bytes, checksum: 378b7c9054c2630188a3afe44b97b7e6 (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-04-26T13:14:26Z (GMT) No. of bitstreams: 1 magnabosco_wj_dr_bot.pdf: 1346455 bytes, checksum: 378b7c9054c2630188a3afe44b97b7e6 (MD5) / Made available in DSpace on 2016-04-26T13:14:26Z (GMT). No. of bitstreams: 1 magnabosco_wj_dr_bot.pdf: 1346455 bytes, checksum: 378b7c9054c2630188a3afe44b97b7e6 (MD5) Previous issue date: 2016-02-26 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Objetivo: A incontinência urinária é uma complicação importante da prostatectomia radical, causando deterioração na qualidade de vida, inclusive no pós-operatório inicial. O objetivo desse estudo foi identificar fatores preditores do retorno precoce da continência após essa cirurgia. Métodos: Foram avaliados 130 pacientes submetidos a prostatectomia radical por meio de um questionário clínico, o estudo urodinâmico, os instrumentos ICIQ-SF (International Consultation on Incontinence Questionnaire – Short Form) e EISP (Escore Internacional de Sintomas Prostáticos), o teste do absorvente de 1 hora, além da perineometria e da eletromiografia do assoalho pélvico. As avaliações foram realizadas antes e 1 mês após a cirurgia. Resultados: A idade mais avançada (> 60 anos) (OR=1,078 IC: 1,007-1,154, p=0,03) foi um fator de risco para a incontinência urinária precoce após a prostatectomia radical enquanto uma maior força de contração do assoalho pélvico antes da cirurgia foi um fator protetor (OR=0,986 IC: 0,974-0,998, p=0,018). No período pós-operatório, os pacientes incontinentes também apresentavam menor força de contração do assoalho pélvico, além de terem mais queixas miccionais, principalmente relacionadas a urgência, além de estarem menos satisfeitos. As taxas de continência variaram de acordo com o critério de avaliação adotado e apresentaram baixo coeficiente de concordância. A presença de contração involuntária do detrusor antes da cirurgia relacionou-se com uma maior taxa de incontinência urinária e padrão urodinâmico de obstrução infra-vesical pré-operatórios, mas não com a perda de urina após a cirurgia. Conclusão: A idade mais avançada e uma menor força de contração do assoalho pélvico foram fatores de risco para a incontinência urinária precoce após a cirurgia. Pacientes incontinentes no pós-operatório tiveram mais sintomas miccionais e uma pior força de contração do assoalho pélvico. / Objective: Urinary incontinence is a major complication of radical prostatectomy, causing quality of life to become worse, even in the initial post operatory period. This article aims to evaluate prognostic factors for early urinary continence following radical prostatectomy. Methods: 130 patients who underwent radical prostatectomy were assessed. The following tests and instruments were used: clinical data questionnaire, urodynamic study, International Consultation on Incontinence Questionnaire – Short Form (ICIQ-SF), International Prostate Symptom Score (IPSS), 1-hour pad test, and pelvic floor muscles perineometry and electromyography. The assessments were performed before, and 1 month after surgery. Results: Older age (OR=1.078 CI: 1.007-1.154, p=0.03) was a risk factor for early urinary incontinence after radical prostatectomy, whereas a stronger contraction force of the pelvic floor before surgery was considered a protective factor (OR=0.986 CI: 0.974-0998, p=0018). In the post operatory period, incontinent patients also presented worse contraction force of the pelvic floor, had more mictional complaints, especially related to urgency, and were less satisfied. Rates of continence varied according to the adopted criteria, and presented low concordance coefficient. Presence of detrusor instability before surgery related to a higher rate of urinary incontinence and urodynamic pattern of bladder outlet obstruction in the preoperative period, but not to urine loss after surgery. Conclusion: Older age and worse contraction force of the pelvic floor were risk factors for urinary incontinence after the surgery. Incontinent patients in the post operatory period had more mictional symptoms and worse contraction force of the pelvic floor.

Made available in DSpace on 2016-06-02T20:30:08Z (GMT). No. of bitstreams: 1 5550.pdf: 829503 bytes, checksum: 5da600d47e06b675663a17677f9bfdc6 (MD5) Previous issue date: 2013-08-30 / Financiadora de Estudos e Projetos / The theory of natural selection as one of the causal processes of Darwin s theory of evolution has impacted on fields of knowledge far beyond natural sciences. This extension the employment of the logic of selection in psychology and philosophy, as can be found in Popper and Skinner is usually defined as ultra-Darwinism. Darwin s ideas and their impact following the publication of The Origin of Species were approached through Ernst Mayr interpretation. The objectives of this study were: (1) to show Darwin s influence on the works of Popper and Skinner; and (2) to present a brief comparison between Popper and Skinner s points of view concerning with the fate of societies. The method employed was an aporetic one. The main results were: (1) The logic of selection makes it possible to find common epistemological features in the works of Popper and Skinner; (2) both authors hold that scientific knowledge is a means for the investigation of culture and cultural planning; (3) both authors agree that essentialistic theoretical beliefs are an obstacle for technological advances and cause of delay in the development of civilization; (4) they are contemporary with events of worldwide impact brought about by mankind throughout the twentieth century that had a great impact on their works. / A teoria da seleção natural como um dos processos causais da teoria da evolução de Darwin atingiu áreas de conhecimento bem além das ciências naturais. Essa expansão o emprego da lógica selecionista na psicologia e na filosofia, que encontramos em autores como Popper e Skinner é o que usualmente se define como ultradarwinismo. As idéias de Darwin, assim como seus efeitos após a publicação de A Origem das Espécies, foram abordadas a partir da interpretação fornecida por Ernst Mayr. O presente trabalho teve como objetivos: (1) Demonstrar a influência do autor inglês nos textos de Popper e Skinner, e (2) Apresentar breves comparações do que produziu Popper com a visão de Skinner como autores preocupados com o destino das sociedades. O método utilizado foi o aporético. Os principais resultados encontrados foram: (1) a lógica selecionista permite evidenciar elementos epistemológicos comuns nos trabalhos de Popper e de Skinner; (2) ambos os autores apontam o conhecimento científico como via de investigação e planejamento cultural; (3) ambos entendem que posições teóricas essencialistas funcionam como obstáculo para o avanço tecnológico e como causa de atraso no desenvolvimento das civilizações; (4) eles são contemporâneos de eventos de impacto mundial promovidos pelo homem no séc. XX, os quais influenciaram as teorias produzidas por ambos.

Este trabalho consistiu de estudos da viabilidade da geração e identificação de radicais livres envolvidos em processos oxidativos avançados por via eletroquímica. Para a geração e identificação de radicais livres em eletrodos modificados com organotióis via eletroquímica, escolheu-se uma técnica pouco aplicada para este fim; a espectroscopia de impedância eletroquímica, e o ajuste dos dados experimentais pela proposta de modelos de circuitos equivalentes. O eletrodo de trabalho utilizado (Au) foi caracterizado em meio ácido e básico e diversas monocamadas auto-organizadas conhecidas foram adsorvidas sobre o mesmo e também caracterizadas por esta técnica. Parâmetros importantes como constante dielétrica, capacitância de uma monocamada livre de defeitos e grau de recobrimento foram determinados com êxito. Também foram empregadas moléculas menos utilizadas como modificadoras de eletrodos (fenotiazinas e derivados). As mesmas foram caracterizadas no sistema Au/adsorvente/NaOH, pois, o pH alto garante a formação do radical superóxido e do ânion hidroperóxido. Os mesmos modelos de circuitos equivalentes puderam ser empregados na obtenção dos parâmetros físicos relativos a essas moléculas no sistema eletroquímico utilizado. Em uma etapa subsequente obteve-se a valiosa informação, se as moléculas adsorvidas sobre Au poderiam ser usadas para a geração de superóxido e outros radicais. As monocamadas de tióis, quando utilizadas para gerar radicais livres, se mostraram aptas a gerar superóxido em meio alcalino saturado com oxigênio molecular. Como se demonstrou na etapa de caracterização, as SAM-3 e SAM-6 não formaram um empacotamento totalmente hidrofóbico. Por este motivo, mesmo que superóxido tenha sido gerado, não pôde ser detectado. Já para a fenotiazina e seu metil-derivado, a cinética de adsorção e a utilização de soluções aquosas impediram a formação de um filme completo e homogêneo, imprescindível para a constituição de uma interface hidrofóbica e isolante. Além disso, possíveis reações de complexação entre as moléculas e superóxido, reações entre a fenotiazina cátion-radical e superóxido fazem necessários mais estudos acerca da natureza eletroquímica do sistema, que já é bastante conhecido fotoquimicamente. Posterior a modificação, todos os eletrodos se mostraram ser bastante sensíveis ao pH e aos eletrólitos utlizados, alterando-se a estrutura interna muito facilmente, o qual implica uma limitação no tempo de uso e reprodutibilidade quando da geração de um radical tão reativo quanto superóxido. / This work consisted in testing the viability of investigations into the electrochemical generation and identification of free radicals involved in advanced oxidative processes. In these studies, a technique which is rarely used for the electrochemical generation and identification of free radicals at organothiole-modified electrodes, electrochemical impedancy spectroscopy, was chosen and the experimental data obtained were fitted by equivalent circuit models. A working electrode (Au) was characterized in both acidic and basic media and several known self-assembled monolayers were adsorbed over this electrode and also characterized using this technique. Important parameters such as dielectric constants, capacitance of the monolayers free of defects and coverage were determined with success. Other lesser-known molecules such as phenothiazines and their derivatives were also used .The modified electrodes were characterized in NaOH solution, since the high pH assures the production of superoxide radicals and hydroperoxylate anions. The equivalent circuit model was employed to obtain physical parameters for these molecules in the electrochemical systems studied. In a subsequent step, a valuable piece of information was obtained; it was noted that the molecules adsorbed over Au could be used in order to generate superoxide and other radicals. The ability of thiol monolayers used in the generation of free radicals, to produce superoxides in alkaline media saturated with molecular oxygen was demonstrated. However, characterization of the self-assembled monolayers, SAM-3 and SAM-6, revealed that these were not able to pack in a completely hydrophobic manner. This may account for the fact that the superoxide could not be detected even when it was believed to have formed. For the phenothiazine-modified electrodes, the adsorption kinetics and the utilization of aqueous solutions prevented the formation of an intact and homogeneous film, which is essential in establishing a hydrophobic and isolating interface. Furthermore, possible complexation reactions between the molecules and the superoxide and reactions between the phenothiazine cation-radical and superoxide, point to the need for further studies regarding the electrochemical nature of this system, whose photochemical properties are very well known. Following modification, all the electrodes were shown to be too sensitive to pH and to the electrolytes used, since the inner structure was easily modified, which implies that they would have a limited time of use and in addition that the reproducibility of the rate of generation of reactive radical species such as superoxides could be compromised.

A reatividade das lupulonas, terpenos, flavonoides prenilados e compostos contendo grupos tióis livre foi avaliada frente ao radical 1-hidroxietila (HER) para melhor conhecer o balanço redox da cerveja. As constantes de velocidade aparentes (kap) para a reação entre HER e os substratos supracitados foram obtidas via cinética de competição utilizando a armadilha química 4-POBN como competidor e monitorando-se o aduto radical formado por RPE. A partir dos valores obtidos de kap (108 L mol-1 s-1 para as lupulonas, 105 a 107 L mol-1 s-1 para terpenos, 109 L mol-1 s-1 para os flavonoides prenilados, e 108 a 109 L mol-1 s-1 para tióis) e pelas concentrações médias destes compostos na cerveja, pôde-se inferir que a extensão da degradação térmica destes compostos na bebida aumenta na ordem: lupulonas > tióis > flavonoides prenilados > terpenos. Os produtos de reação foram identificados por espectrometria de massas, e através de investigações eletroquímicas e cálculos ab initio empregando-se DFT se propôs um mecanismo de reação. Os produtos de degradação pela reação com HER foram: derivados hidroxilados e compostos de adição do radical HER para as lupulonas; derivados hidroxilados para os terpenos; derivados de adição do radical HER para os flavonoides prenilados; e dissulfetos para os tióis. Em experimento similar foram determinadas as kap para a reação entre metil ésteres derivados de ácidos graxos insaturados e esteróis com o HER, cujos valores de kap variaram de (2,7 ± 0,1) x 107 até (5,2 ± 0,1) x 107 L mol-1 s-1 para o metil docosahexanoato e ergosterol, respectivamente. Os dados cinéticos aqui obtidos contribuem para um melhor conhecimento da degradação térmica oxidativa da cerveja, bem como sugerem que os polifenóis prenilados podem conferir um significativo efeito antioxidante ao organismo humano quando do seu consumo e absorção. / The reactivity of lupulones, terpenes, prenilated flavonoids and thiol-containing compounds was evaluated towards the 1-hydroxyethyl radical (HER) to provide a better knowledge of the redox balance of beer. The apparent rate constants (kap) for the reaction between HER and the substrates were obtained through a competitive kinetic approach using the spin-trap 4-POBN as a competitor and by monitoring the radical adduct by EPR. From the obtained values of kap (108 L mol-1 s-1 for lupulones, from 105 to 107 L mol-1 s-1 for terpenes, 109 L mol-1 s-1 for prenylated flavonoids, and from 108 to 109 L mol-1 s-1 thiol compounds) and the average concentrations of these compounds in beer, it is possible to infer that the extension of the thermal degradation on the beverage is enhanced according to: lupulones > thiol compounds > prenylated flavonoids > terpenes. The reaction products were identified by mass spectrometry, and by electrochemical investigations and ab initio (DFT) calculation, a reaction mechanism has been proposed. The degradation products for the reaction with HER were: hydroxide derivatives and HER addition products for the lupulones; hydroxide derivatives for terpenes; HER addition derivatives for prenylated flavonoids; and disulfides for thiol cmpounds. In similar experiments it was determined the kap for the reaction among methyl ester derivatives of unsaturated fatty acids and sterols with HER, with kap values ranging from (2.7 ± 0.1) x 107 to (5.2 ± 0.1) x 107 L mol-1 s-1 for the methyl docosahexanoate and ergosterol, respectively. The obtained kinetic data may contribute for a better knowledge of the thermal oxidative degradation of beer, as well as may suggest that prenylated polyphenols could present a significant antioxidant effect in the human body through its consumption and absorption.

Made available in DSpace on 2015-05-07T15:09:13Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 12565097 bytes, checksum: ef1d94b51a832f975313347e08b4dd18 (MD5) Previous issue date: 2014-02-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This thesis proposes an investigation of citizenship education in Brazil, taking as a reference the relationship between citizenship and the educational process that takes place at secondary school in the country, particularly in the scope of the school subject Sociology. The research focuses on the comparative analysis of the meanings of citizenship identified in students discourse by reference to their curricular experiences, especially in the field of Sociology, the conceptions of citizenship articulated in the discourse of curriculum guidelines for the teaching of Sociology at secondary school level and the considerations about citizenship education that emerge in the discourse of the Sociology teachers of the participating students. Students discourse was observed through the analysis of mind maps on the theme of citizenship constructed by 21 students from a local secondary school, and it was related to the analysis of specific curriculum guidelines for the teaching of Sociology at secondary school (the National Prescribed Outcomes, the National Guidelines and the local State Guidelines) and to the investigation of the teachers discourse, articulated through interviews. It is a case study, and the methodology used for analyzing data was anchored on the theoreticalepistemological framework and on categories of Discourse Theory proposed by Ernesto Laclau and Chantal Mouffe, among which we highlight: discourse, hegemony, the axes of equivalence and difference, floating signifier, articulation, antagonism and dislocation. The study of the distinct discursive formations above-mentioned was aimed at analyzing which conceptions of citizenship appear as hegemonic in the educational arena, considering the dynamics of interdiscursivity and the intertwining of citizenship conceptions and the dimensions of agency, experience and identification. Citizenship education was discussed taking as a reference three analytical perspectives: a developmental perspective or of social responsibility, a critical or justice-oriented perspective and a perspective of everyday practice and process. In the end, we suggested some implications of the meanings of citizenship identified as hegemonic in the educational discourses observed. Those implications affect curriculum development and the pedagogical process in specific ways, enabling those aspects to contribute (or not) to the emergence of participatory citizens, not only from a social, but also from a political point of view, and facilitating (or not) the strengthening of radical and plural forms of democracy. / Essa pesquisa se dirige a investigar aspectos da educação para a cidadania no Brasil, tomando como referência a relação entre a cidadania e o processo educacional que ocorre no espaço escolar do ensino médio, sobretudo no âmbito da disciplina Sociologia. O foco da pesquisa é a comparação dos sentidos de cidadania identificados nos discursos de alunos, a partir de suas vivências curriculares de Sociologia, com os significados presentes nos discursos dos documentos curriculares para o ensino dessa disciplina no nível médio, e também cotejando tais sentidos com as considerações sobre as abordagens de educação para a cidadania que transparecem no discurso dos professores de Sociologia dos alunos participantes. O discurso dos alunos foi observado a partir de mapas mentais com foco na cidadania construídos por 21 estudantes de uma escola secundária da cidade de João Pessoa, e foi relacionado à análise de documentos curriculares para o ensino de Sociologia no nível médio (PCN, OCEM e Referenciais para o Ensino Médio da Paraíba), e ao discurso dos professores, observado a partir de entrevistas. Trata-se de um estudo de caso, e a metodologia de análise utilizada se apoiou em pressupostos teórico-epistemológicos e em categorias da Teoria do Discurso de Ernesto Laclau e Chantal Mouffe, dentre as quais destacamos: discurso, hegemonia, eixos da equivalência e diferença, significante flutuante, articulação, antagonismo e deslocamento. O estudo das diferentes formações discursivas mencionadas se voltou para analisar que concepções de cidadania são hegemonizadas no campo educacional, observando as dinâmicas de interdiscursividade e o imbricamento dessas concepções com as dimensões de agência, experiência e identificação. A educação para a cidadania foi discutida tendo por base três perspectivas de análise: uma perspectiva desenvolvimentista ou de responsabilidade social, uma perspectiva crítica ou voltada para a justiça social, e uma perspectiva de processo e prática do cotidiano. Ao final da pesquisa, sugerimos algumas implicações dos sentidos de cidadania priorizados nos campos educacionais observados. Tais implicações repercutem no desenvolvimento de um trabalho pedagógico e curricular de maneiras específicas, que podem contribuir (ou não) para a emergência de cidadãos participativos não só do ponto de vista social, mas também político, e que podem ser relevantes (ou não) para o fortalecimento de formas radicais e plurais de democracia.

Cette thèse présente des travaux de méthodologie de synthèse et des études mécanistiques. Une approche complémentaire est utilisée, avec des résultats expérimentaux et des résultats théoriques issus de calculs DFT. Trois réactions ont été étudiées. La première réaction est l’alpha-arylation de cétones énolisables en l’absence de métal de transition. Elle se déroule en présence de DMF et de tBuOK. L’étude mécanistique met en évidence la formation d’une espèce riche en électrons par déprotonation du solvant. La deuxième réaction étudiée est la N-arylation de pyrazoles via la formation d’aryldiazoniums in situ. Cette réaction est catalysée au cuivre. Une évaluation de la méthode DFT la plus adaptée est présentée. Un double cycle catalytique est proposé, faisant intervenir le complexe de cuivre et l’acide acétique. La dernière réaction étudiée est la formation stéréoselective d’alkényl thioethers fluorés trisubstitués par catalyse au cuivre. La méthodologie de synthèse est présentée, suivie d’une étude mécanistique. Celle-ci révèle un mécanisme radicalaire qui peut être généralisé à d’autres substrats. / In this thesis, synthetic methodology development and mechanistic studies are presented. A complementary approach, using both experiments and theoretical outcomes from DFT, is used. Three reactions were studied. The first reaction is the transition-metal free alpha-arylation of enolizable ketones. It proceeds using DMF and tBuOK. The mechanistic study reveals the formation of an electron-rich species by deprotonation of the solvent. The second reaction studied is the copper-catalyzed N-arylation of pyrazoles with arenediazonium salts generated in situ. A benchmark is performed to evaluate the best DFT methodology. A double catalytic cycle is proposed, involving copper and acetic acid. The last reaction studied is the copper-catalyzed stereoselective access to trisubstituted fluorinated alkenyl thioethers. The development of the methodology is presented. Then a mechanistic study reveals a radical mechanism that can be generalized to other substrates.