Made available in DSpace on 2016-03-15T19:48:58Z (GMT). No. of bitstreams: 1 Olivar Alves Pereira.pdf: 1411844 bytes, checksum: ad21c031f20fb94eb86a9afee2d4135c (MD5) Previous issue date: 2010-02-25 / Discusses Theology of Secularization as proposed by the Baptist theologian Harvey Gallagher Cox Jr., who emerged in the academic and literary scene in the 1960s in full uproar caused by the Radical Theology, popularly known as the Movement of the Death of God. Analyzes five major works of that author who deal directly with the secularization and its implications for Christianity both Catholic and Protestant, and this analysis highlights what Harvey Cox proposes to search for the plausibility of Christianity. Thus, it follows that not all claims that Harvey Cox did in the 1960s about religion were correct, such as those related to the decline of religiosity, however, other claims sound like "prophetic" and have occured accurately. Aditionally, in order to do justice to the thought of that theologian it should not identify him as a "theologian of the death of God", but rather as a "theologian of secularization". Finally, if Christianity, represented by the Church (Catholic and Protestant) wants to be considered relevant during these days and in the future must be engaged in the society and serve it even having to deal with the declared atheism of such society. / Aborda a Teologia da Secularização assim proposta pelo teólogo batista Harvey Gallagher Cox Junior, o qual despontou no cenário acadêmico e literário na década de 1960 em pleno alvoroço causado pela Teologia Radical, popularmente conhecida como o Movimento da Morte de Deus. Analisa as cinco principais obras do referido autor que tratam diretamente da secularização e suas implicações para o Cristianismo tanto o católico como o protestante, e nessa análise destaca-se o que Harvey Cox propõe para a busca da plausibilidade para o Cristianismo. Conclui-se que nem todas as afirmações que Harvey Cox fez na década de 1960 sobre a religião estavam corretas, tais como as que se referiam ao declínio da religiosidade; contudo, outras afirmações deles soam como proféticas e se cumpriram com exatidão. Também que para se fazer justiça ao pensamento desse teólogo não se deve identificá-lo como um teólogo da morte de Deus , mas, sim, como um teólogo da secularização . E por fim, o Cristianismo representado pela Igreja (católica e protestante) se quiser encontrar-se relevante para esses dias e no futuro deverá se engajar na sociedade e servi-la mesmo tendo que lidar com o ateísmo declarado dessa sociedade.

Este trabalho busca compreender as amarras e as potencialidades em torno do uso das mídias digitais por ativistas autônomos anticapitalistas. O objetivo é partir da discussão sobre a potência democratizante que a Internet ativa e chegar à análise de coletivos autônomos que produzem e divulgam no espaço digital um discurso anticapitalista. Embora as novas mídias façam parte da indústria na qual a informação é mercadoria e meio de reprodução da lógica de produção vigente, a existência de grupos que usufruem das mídias digitais para criticar o atual modelo político, econômico e social contribui para o crescimento descentralizado da construção e difusão do pensamento antissistêmico. Portanto, interessa a esta pesquisa refletir sobre as origens desse ativismo e seu potencial de transformação social. A narração de episódios recentes da trajetória do movimento autônomo - o levante zapatista, a Ação Global dos Povos e as ocupações de 2011- vai ajudar na compreensão de elementos encontrados nos protestos de junho de 2013 e na formação de uma rede de coletivos em espaços físicos e virtuais. A coleta de dados de redes sociais e entrevistas com militantes basearão a descrição das ações comunicativas empreendidas por esses ativistas. / This paper seeks to understand the limits and potentialities surrounding the use of digital media by autonome anticapitalist activists. The purpose is to depart from the discussion about the democratizing potency that Internet activates and reach the analysis of autonome movements that produce and publish in the digital environment an anticapitalist speech. Although new media takes part of industry where information is merchandise and way of reproducing the logic of the current production, the existence of groups that take advantage of digital media to criticize the current political, economic and social model contributes to the decentralized growth of construction and dissemination of antisystemic thought. Therefore, this research is interested in reflect on the origins of this activism and its potential for social transformation. The narration of recent episodes of the trajectory of the autonomous movement - the Zapatista insurrection, the People\'s Global Action and occupations in 2011 - will help in the understanding of elements found in the protests of June 2013 and the formation of a network of collectives in physical and virtual spaces. The collection of data from social networks and interviews with militants will base the description of communicative actions undertaken by these activists.

Os efeitos de ribonucleosídeos de guanina substituídos na posição C-8 na proliferação de linfócitos B estão bem documentados na literatura. Esses compostos são análogos de adutos formados pela adição de radicais livres a ribonucleosídeos e a RNA. Neste trabalho, verificamos as propriedades proliferativas de dois desses adutos, 8-metilguanosina (8-MeGuo) e 8-oxo-7 ,8-di-hidroguanosina (8-OxoGuo) e comparamos com 8-bromoguanosina (8-BrGuo), o composto mais estudado como indutor da proliferação de linfócitos B. 8-MeGuo e 8-OxoGuo foram sintetisados em rendimentos de 28 e 55%, respectivamente, e foram caracterizados por UV, NMR e CG-massa. Seus efeitos sobre a incorporação de timidina radioativa ([3H] TdR) no DNA de células de baço, fibroblasto 3T3(A31) e melanoma B16F10 foram examinados. Os dois adutos foram mitogênicos para células de baço mas foram seletivos quanto as células imortalizadas. 8-MeGuo atuou sobre células 3T3(A31) e 8-OxoGuo sobre as células de melanoma B16F10. O análogo não fisiológico 8-BrGuo foi efetivo em todas as células testadas. Experimentos de contagem de células, citotoxicidade e citometria de fluxo, indicaram que a síntese de DNA induzida pelas guanosinas substituídas na posição C-8 refletia crescimento celular. Foi proposto que os compostos agem de dentro da célula uma vez que seus efeitos são bloqueados em presença de um inibidor de transporte de nucleosídeo, mas não foram inibidos por um antagonista de receptor purinérgico. Os resultados obtidos, junto com os descritos na literatura, sugerem que no caso dos fibroblastos 3T3(A31) e células de baço de camundongo os efeitos proliferativos dos compostos não são dependentes do metabolismo desses compostos via salvação das purinas. No caso das células de melanoma, entretanto, os compostos parecem fazer parte do \"pool\" de nucleosídeos. A demonstração de que adutos produzidos por ataques radicalares em ribonucleosídeos e RNA são capazes de induzir proliferação celular, abre novas perspectivas para a compreensão do papel de radicais livres em processos carcinogênicos. / The ability of CS-substituted guanine ribonucleosides to induce B cell proliferation has been well documented in the literature. These compounds are analogues of adducts formed from free radical attack on ribonucleosides and RNA. Here we examined the proliferative properties of two of these radical adducts, 8-methylguanosine (8-MeGuo) and 8-oxo-7 ,8-dihydroguanosine (8-OxoGuo) and compared them with those of the well studied B cell mitogen, 8-bromoguanosine (8-BrGuo). 8-MeGuo and 8-OxoGuo were synthesized in yields of 28 and 55 %, respectively, and were characterized by UV, NMR and CG-MS. Their effects upon [3H] thymidine uptake by Swiss mice splenocytes, mouse embryo 3T3 (A31) fibroblasts and mouse B16F10 melanocytes were examined. Both guanosine radical adducts were shown to increase [3H] thymidine uptake by mice splenocytes but displayed selectivity in regard to continuous cell lines. 8-MeGuo acted upon 3T3(A31) fibroblasts whereas 8-OxoGuo acted upon B16F10 melanocytes. The non physiological analogue 8-BrGuo acted upon all tested cells. Parallel experiments of cell counting, cytotoxicity, and cell sorting indicated that DNA synthesis induced by the C8-substituted guanosines reflected cell growth. It is proposed that the compounds act intracellularly because their proliferative effects were blocked in the presence of a nucleoside transport inhibitor but were not inhibited by an antagonist of the A2 purine receptor. The obtained results, taken together with data from the literature suggest that in the case of 3T3 (A31) fibroblasts and mice splenocytes the proliferative effects of the compounds are not dependent on metabolism through purine salvage pathways. In the case of melanocytes, however, the compounds are likely to become part of the purine nucleoside pool. The demonstration that adducts produced by free radical attack on ribonucleosides and RNA are able to induce cell proliferation opens new perspectives for the understanding of free radical mediated carcinogenesis.

Jacques Derrida est signataire de ce qu’on appelle une "œuvre" : un vaste corpus de textes où d’autres "œuvres", en grand nombre, sont citées, étudiées, analysées ou déconstruites. Souvent, il utilise le mot "œuvre", et plus rarement mais de manière significative, il interroge ce mot ou ce qu'il appelle l'"énigme" du concept d'œuvre. Dans ce qu’il « dit » alors, un double « faire » est impliqué. D’une part, il se demande « Que fait cette œuvre ? », et nous pouvons analyser et commenter ce qu’il dit. Mais d’autre part, nous pouvons aussi nous demander : « Mais que fait Derrida quand il analyse ce que fait cette œuvre ? ». C’est cette deuxième question qui tend à prévaloir dans cette étude. Dans les champs de l'histoire de l'art, de l'esthétique ou de la critique littéraire, il existe une immense littérature autour de la question de l'œuvre. La convoquer, dans le format limité de ce travail, aurait conduit à des simplifications, des approximations ou des omissions. On a donc fait un autre choix : chercher dans le texte derridien lui-même, dans son faire, son auto-hétéro-affection, les éléments qui pourraient conduire à l’élaboration d’un concept d'œuvre spécifique et singulier. Afin de tenir compte de la critique externe et aussi de la longue histoire de la philosophie autour de cette thématique, on a mis à profit la structure d'"invagination" du texte derridien. Dans ce texte même, en prenant appui sur la littérature secondaire, on peut repérer d'autres pensées de l'œuvre, par exemple celles de Lévinas ou d’Heidegger. Cette méthode a conduit aux hypothèses suivantes : 1. Il y a dans l'œuvre derridienne, y compris à travers l’analyse des autres œuvres, la mise en jeu d’un "Il faut", d’une ou de plusieurs inconditionnalité(s), et ce dès les premiers textes. 2. La structure d'auto-immunité, décrite dans l'œuvre, opère dans l'œuvre. "Il faut" se protéger contre quelque chose. Quoi? Notre hypothèse, c'est qu'il s'agit du mal radical. 3. Malgré les apories multiples dont la description occupe une large partie de l'œuvre, le désir de protection, en principe impossible à réaliser, réussit quand même. On peut tenter de démontrer cette réussite, mais on peut aussi, surtout, en témoigner par la lecture : Je dois reconnaître, je dois avouer qu'elle me vaccine. 4. Cette opération, que nous nommons aussi "œuvrance", est performative. Elle passe par cinq principes inconditionnels : laisser l’avenir ouvert, s’adresser à l’autre comme tel, s’aventurer pour plus que la vie, garder le secret, répondre des principes - en ce moment même. 5. Cela conduit à la définition d'un "principe de l'œuvre" spécifique de l’œuvre derridienne dont l'énoncé est le suivant : Ce qui a lieu dans une œuvre s’affirme inconditionnellement, en-dehors de tout calcul, de toute finalité et de toute transaction. / Jacques Derrida signs what is called “une oeuvre” ("a work") : a vast corpus of texts, in which other "works", great in number, are cited, studied, analyzed or deconstructed. He often uses the word "work", and more rarely, but in a significant way, he interrogates this word, or what he calls "the enigma" of the concept of work. In what he "says", then, a double "doing" is implied. On the one hand, he asks himself "What makes this work?", and we can analyze and comment upon what he says. But, on the other hand, we can also ask ourselves : "But what does Derrida do when he analyzes what it is that makes this work?" This second question is the one that tends to prevail in this study. In the fields of art history, esthetics or literary criticism, there exists an enormous litterature around the question of the work. To raise it, in the limited form of this essay, would lead to simplifications, approximations, or omissions. We have therefore made another choice : to seek out, in the derridian text itself, in its "doing", its auto-hetero-affection, the elements that could lead to the elaboration of a specific and singular concept of work. In order to account for external criticism, and also of the long history of philosophy around this thematics, we have privileged the Derridian text's structure of "invagination". In his text itself, drawing on the secondary literature, we can link up other thoughts involving the work, for example those of Levinas or Heidegger. This method has lead to the following hypotheses: 1. In the derridian work, including across the analysis of other works, the setting into play of an "it must", of one or several unconditional(s), and beginning with the first texts. 2. The structure of auto-immunity, described in the work, is operating within the work. "It must" protects itself against something. Against what? It is our hypothesis that this has to do with radical evil. 3. Despite the multiple aporias whose description occupies a large part of his work, the desire for protection, in principle impossible to realize, nonetheless succeeds. We can try to demonstrate this success, but we can also, above all, take note of it by reading : I ought to recognize, I ought to acknowledge that it vaccinates me. 4. This operation, that we also call “œuvrance” (“working”), is performative. It passes through five unconditional principles : leave the future open, address oneself to the other as such, aim for more than life, keep the secret, answer to principles -- in this very moment. 5. This leads to the definition of a "principle of the work": specific to the derridian work whose statement is the following : what takes place in the work, is unconditionally affirmed, beyond all calculation, all finality and all transaction.

O Brasil possui uma imensa diversidade biológica, na qual muitos compostos bioativos podem ser encontrados e utilizados em beneficio à sociedade. No entanto, processos de degradação do ambiente e introdução de espécies exóticas têm contribuído ao conhecimento e uso limitadosde muitas plantas nativas, sendopequena a quantidade de estudos sobre sua composição química e potencial biológico. A prevenção de doenças crônicas constantemente vem sendo associada à atividade antioxidante de metabólitos secundários dos vegetais, principalmente os fenólicos. Assim, o objetivo deste trabalho foi avaliar a atividade antioxidante e composição fenólica de cinco espécies frutíferas nativas do Brasil (G. brasiliensis, E. leitonii, E. involucrata, E. brasiliensis e E. myrcianthes). Os métodos capacidade de redução do Folin-Ciocalteau, autoxidação do sistema ?-caroteno/ácido linoleico, capacidade de absorção de radicais oxigênio (ORAC), sequestro dos radicais livres DPPH e ânion superóxido foram aplicados na determinação da atividade antioxidante dos extratos etanólicos de folha, casca, semente e polpa das espécies selecionadas. As amostras demonstraram significativa atividade antioxidante e, em alguns casos, superior as frutas comumente consumidas pela população brasileira. Em geral, folhas apresentaram as maiores atividades, mas o destaque foi a semente de E. leitonii que exibiu os melhores resultados em quatro dos cinco métodos utilizados: 120,67 mg AG.g-1 na redução do reagente Folin; 7,08 Gmol Trolox.g-1 no ?-caroteno; EC50 de 0,26 mg.mL-1 e 0,07 mg.mL-1 no sequestro do ânion superóxido e DPPH, respectivamente; 514,75 Gmol Trolox.g-1 no ORAC para o qual a folha de E. involucrata obteve o maior valor (1393,3 Gmol Trolox.g-1). Os extratos das espécies nativas também demonstram efeito antioxidante contra radicais de relevância biológica, como peroxila e superóxido. Por meio de CG-EM e CLAE acoplado a arranjo de fotodiodos, os principais compostos fenólicos encontrados nos extratos vegetais foram catequina, epicatequina e ácido gálico. Este trabalho demonstrou o grande potencial antioxidante das frutíferas nativas brasileiras, evidenciando assim possível efeito positivo em sistemas biológicos. / Brazil has a great biodiversity, in which many bioactive compounds can be found and used to benefit the society. However, environmental degradation processes and introduction of exotic species have contributed to limited use and knowledge of many native plants, reflecting in few studies about chemical composition and biological potential. The prevention of chronic diseases has been constantly associated with the antioxidant activity of plants secondary metabolites, mainly the phenolics. The objective of this study was to evaluate the antioxidant activity and the phenolic composition of five Brazilian native fruitful species (G. brasiliensis, E. leitonii, E. involucrata, E. brasiliensis e E. myrcianthes). The methods of Folin-Ciocalteau reducing capacity, co-oxidation of ?-carotene/linoleic acid system, oxygen radical absorbance capacity (ORAC), DPPH and superoxide free radical scavenging were used to determine the antioxidant activity of ethanolic extracts of leaf, peel, seed and pulp of the selected species. The samples showed significant antioxidant activity and, in some cases, it was superior to fruits commonly consumed by Brazilian population. In general, leaves presented the highest activities, but the seed of E. Leitonii stood out exhibiting the best results in four of the five methods: 120.67 mg GA.g-1 in the Folin reducing; 7.08 Gmol Trolox.g-1 in the ?-carotene; EC50 of 0.26 mg.mL-1 and 0.07 mg.mL-1 in the superoxide and DPPH scavenging, respectively; 514.75 Gmol Trolox.g-1 in the ORAC, for which the E. Involucrata leaf had the highest value (1393.3 GmolTrolox.g-1). The extracts of native species also demonstrate antioxidant effect against radicals of biological relevance, such as peroxyl and superoxide. By GC-MS and HPLC coupled to a photodiode array, the major phenolic compounds found in the plant extracts were catechin, epicatechin and gallic acid. In this study, Brazilian native fruitful presented high antioxidant potential, showing a possible positive effect on biological systems.

Un des problèmes majeurs en enzymologie est la fonctionnalisation de liaisons C-H peu réactives. Ces réactions nécessitent des cofacteurs spécialisés tels que l'hème, des Fer-oxo ou encore la vitamine B12. En 2001, il a été montré que des centres Fe-S particuliers liant la S-Adénosyle méthionine (SAM) pouvaient activer des liaisons C-H non réactives. Les enzymes utilisant ce cofacteur constituent une super-famille appelée « Radical SAM ». Les thiométhyltransférases (MTTases) sont des enzymes « Radical SAM » qui catalysent l'insertion d'un groupe thiométhyle (-SCH3) dans des liaisons C-H non réactives. Par des expériences in vivo et in vitro, nous avons montré qu'on pouvait les regrouper en trois classes. La première classe (RimO) catalyse la formation du β-thiométhylaspartate 89 sur la protéine ribosomale S12 (β-ms-D89-S12) alors que les deux dernières (MiaB et MtaB/eMtaB) catalysent respectivement la thiométhylation des nucléosides 2-methylthio-N6-isopentenyladenosine 37 (ms2i6A-37) et 2-methylthio-N6-threoninecarbamoyl adenosine 37 (ms2t6A-37) de certains ARNts. L'étude in vitro du mécanisme de ces enzymes a permis de démontrer que les MTTases catalysent l'insertion d'un groupement -SCH3 de façon catalytique invalidant l'hypothèse généralement retenue dans la littérature que le soufre inséré dérive de la destruction d'un centre Fe-S. / One of the chemically most challenging problems in enzymology is the functionalization of non-reactive C–H bonds. Such reactions require specialized cofactors as heme, Fe-µ-oxo or vitamin B12. In 2001, special Fe-S centers able to bind S-Adenosylmethionine (SAM) have been shown to activate non-reactive C-H bonds toward subsequent functionalization. Enzymes containing this new cofactor constitute a super-family called “Radical SAM”. Methylthiotransferases (MTTases) belong to the “Radical SAM” super-family and catalyse the insertion of a methylthio group (-SCH3) in C-H bonds. By doing in vitro and in vivo experiments, we were able to classify them into three groups. The first class, (RimO) catalyses the formation of β-methylthio-aspartate 89 on the ribosomal protein S12 (β-ms-D89-S12) whereas the two others (MiaB and MtaB/eMtaB) respectively catalyse the thiomethylation of the nucleosides 2-methylthio-N6-isopentenyladenosine 37 (ms2i6A-37) and 2-methylthio-N6-threoninecarbamoyl adenosine 37 (ms2t6A-37) present in some tRNA. Our studies have shown that, in vitro, MTTases catalyse the insertion of a SCH3 group in a catalytic way suggesting entirely new radical sulfur insertion mechanisms.

The first project in this dissertation describes the use of microwave-promoted iminyl radical fragmentations to form functionalized nitriles. Nitrogen-centered radical chemistry is a useful tool to construct valuable C-N bonds commonly found in pharmaceuticals and biologically active molecules. Classically, these reactions require the use of toxic initiators and propagators. Iminyl radical chemistry has been gaining momentum as a means of avoiding these harsh conditions. This project utilizes the fragmentation of cyclic iminyl radicals via irradiation of O-phenyl oxime ethers to produce a synthetically useful nitrile tethered to an alkyl radical in the absence of metal catalysts and redox chemistry. The efficacy of this synthetic method was demonstrated by the diverse functionalization of estrone. We believe this useful chemistry can be a powerful tool when applied to both early and late-stage synthetic endeavors. The latter half of this dissertation focuses on the total synthesis of yaku'amide A, a natural product isolated from a marine sponge. This peptide contains potent anticancer activity and exhibits a novel, unique mode of action. Due to its scarcity in nature, comprehensive biological studies have remained elusive. The structure of yaku'amide A contains complex, unsymmetrical bulky dehydroamino acids such as E- and Z- dehydroisoleucine which pose a synthetic challenge. Despite the efficient strategy developed in our lab, the synthesis remains lengthy. Simpler symmetrical dehydroamino acids dehydrovaline and dehydroethylnorvaline were substituted in place to prepare two analogues of yaku'amide A that closely resemble the conformation of the natural peptide. Activity profile of the simplified analogues showed comparable potency to that of yaku'amide A.

Orientador: Juarez Tadeu de Paula Xavier / Resumo: Esta dissertação apresenta uma análise da cobertura da eleição presidencial de 2018 realizada pela Agência Pública. O objetivo da pesquisa é questionar por meio de um Estudo de Caso, de que maneira, este veículo de mídia radical contribuiu para o debate democrático na cobertura da eleição presidencial. Foram analisadas 21 reportagens publicadas online entre agosto e dezembro de 2018. A seleção do corpus de análise foi realizada por meio de buscas pelas palavras-chave “Eleições 2018 e Bolsonaro”, depois de selecionado o material foi analisado em três aspectos: temáticas, abordagens e fontes. O trabalho também propõe no referencial teórico uma abordagem reflexiva sobre jornalismo e democracia, crise de credibilidade no jornalismo e como a tecnologia viabilizou a atuação e disseminação das mídias radicais que apresentam propostas disruptivas aos modelos hegemônicos de produção informativa. Com base nas análises das temáticas, abordagens e fontes utilizadas nas reportagens, a pesquisa aponta que a Agência Pública propôs o debate de assuntos relevantes para a população durante o processo eleitoral, atuando na ampliação do debate democrático e no combate à desinformação. / Abstract: This study brings an analysis of the Public Agency news coverage of 2018 presidential elections. By means of a case study, the aim of this work is questioning how this radical media press contributed to a democratic debate on the coverage of presidential elections. There were analyzed 21 media reports published online between August and December 2018. The corpus selection for the analysis was done by researching for the keywords “2018 Elections” and “Bolsonaro”. After that, the features were analyzed by three aspects: subject, approach and sources. Also, the work suggest in the theoretical standard a reflexive approach about journalism and democracy, credibility crisis in journalism and how technology enable the radical medias acts and dissemination, which offer disruptive proposes to the hegemonic roles of informative production. Based on the analysis of the subjects, approaches and sources used in these reports, the research points out Public Agency suggest a debate of relevant topics for the population during electoral process, acting to widen up the democratic debate and the fight against misinformation. / Mestre

This thesis forms a report including human security and economic aspect experienced by three groups that are Radical right, Radical left, and the refugees. The examined theory is based on the securitisation of the EU sphere since the 2014/2015 refugee crisis and the Eurozone crisis. Economic perspective has a place in the public discourse inside the EU sphere, presenting moral dilemmas and political obligations of aiding the refugees in ethical scrutiny of human rights and human security.However, the de-radicalisation of the EU sphere deserves pointing attention to radicalised individuals and the reasons supporting both radicalisation and isolation. Therefore, human security assessment is made in three different groups to prioritise all the groups in the research: The refugees have participated with the presentatives of Radical right and Radical left ideology in the interviews. Data collected from the interviews and literature review include background information on the causes of the refugee movement, the EU-sphere migration process, and the organisations related to administrating and supporting the refugees and asylum-seeking process. The data of the research could be used by report makers, educators, and scholars.

Le but de cette proposition est d'explorer un nouveau concept de matériaux moléculaires sensibles à l'oxydoréduction. Les architectures commutables électron-sensibles ont longtemps été reconnues comme le choix le plus simple et le plus viable pour produire des dispositifs pratiques, mais la conception efficace de tels systèmes à l'échelle moléculaire reste un défi. L'approche développée dans ce projet repose sur la production électrochimiquement déclenchée de radicaux pi à partir de dérivés de viologène, l'objectif étant d'induire la formation d'une liaison non-covalente et réversible entre ces radicaux pi pour contrôler la conformation des échafaudages supramoléculaires. Les nanomatériaux comprendront des fils moléculaires provenant de polymères de coordination et des fils moléculaires produits par des interactions π le long de l'axe du fil, mis en œuvre par des interactions faibles périphériques telles que l'agrégation des chaînes latérales lipophiles ou la liaison H. Les efforts initiaux se concentreront sur l'optimisation de la formation de π-dimères et de pimer, avec ou sans assistance d'interactions secondaires. Après avoir déterminé les paramètres qui produisent l'auto-assemblage dirigé π le plus efficace, des motifs basés sur les viologènes appropriés seront introduits dans des blocs de construction plus sophistiqués. Tout au long de la synthèse des assemblages, la π-dimérisation utilisée comme force motrice principale pour l'auto-assemblage des nanomatériaux peut être consolidée par un blocage covalent des structures. En fin de compte, l'électrostimulation des systèmes π fournira des assemblages moléculaires dynamiques dans lesquels la morphologie sera sensible aux stimuli redox. / The aim of this proposal is to explore a new concept of redox-responsive molecular materials. Electron-responsive switchable architectures have long been recognized as the most straightforward and viable choice to produce practical devices but efficiently designing such systems on the molecular scale still remains a challenge. The approach developed in this project relies on the electrochemically triggered production of pi-radicals from viologen derivatives, the objective being to induce the formation of non-covalent and reversible binding between these pi-radicals to control the conformation of supramolecular scaffolds. The nanomaterials will comprise molecular wires arising from coordination polymers and molecular wires produced by π-interactions along the wire's axis implemented by peripheral weak interactions such as lipophilic side chain aggregation or H-bonding. The initial efforts will focus on the optimization of π-dimer and pimer formation, with or without assistance of secondary interactions. After determining the parameters that yield the most efficient π directed self-assembly, suitable viologen based motifs will be introduced in more sophisticated building blocks. Throughout the synthesis of the assemblies, π-dimerization that is used as the primary driving force for the self-assembly of nanomaterials may be consolidated by covalent locking of the structures. In the end, the electro-stimulation of π systems will provide dynamic molecular assemblies in which the morphology will be responsive to redox stimuli.