L'instant comme l'instantanéité se confrontent à une ambiguïté temporelle. Ils se heurtent à une fragmentation, à laquelle la photographie ne saurait se résoudre. Elle ne saurait se contraindre à une coupe immobile du temps, car le sens ontologique de l'image photographique contemporaine glisse. Il se dérobe à l'ancrage passé, daté et révolu lié notamment à la pensée barthienne et nécessite une redéfinition détachée de la perception mortifère de La Chambre Claire. Il révèle les carences des outils théoriques susceptibles de saisir l'essence de la création photographique. Il nous engage dans une requalification de son élaboration, de sa substance, comme de son étude. Entre déstructuration et restructuration nous défendons une forme susceptible de repousser les bornes de l’instant vers une densité de temps, de drame. Nous composons une situation photographique dont les perspectives troublent, inquiètent, interrogent. Par une poïétique de la dérive, du manque et de l'incertitude, nous constituons un événement carencé. Nous déterminons une circonstance suffisamment pesante pour laisser planer sur l'instant le poids d'une tension. L'instance puiserait ainsi du manque, du doute, un ressort dramatique comme une hypothèse de recherche tournée vers une appréhension, non sans évoquer l'expérience éprouvante liée au défilement des images. / Instant as immediacy confront them with temporal ambiguity. They come up against a fragmentation in which the photography couldn't be resolved. It couldn't be restrained itself to a stationary cutting time, because the ontological sense of contemporary photography slips. It eludes the past, dated and bygone idea linked to Barthes's thought especially and requires a redefinition detached of the deadly perception of the Camera Lucida. It reveals deficiency of theoretical tools open to capture the essence of creative photography. It commits us to an amendment of its elaboration, its substance and its study as well. Between destructuring and restructuring, we defend a form which is able to push away instant limits towards time and drama density. We compose a photographic situation whose prospects trouble, worry, question. We establish a deficient event, thanks to a poietic of drift, lack and a state of uncertainty. We also determine a sufficiently heavy circumstance to let the weight of a tension hang over the moment. So photographic pending would draw from lack and doubt, a dramatic device as a research hypothesis turned towards an apprehension, not without mentioning the trying experience of scrolling images.

Ces quarante dernières années, Louise Glück a su s’imposer dans le paysage de la poésiecontemporaine américaine sans que l’on ait jamais pu l’assigner à quelque genre que ce soit. Sa poésie déroute car traversée par le féminin, elle s’obstine pourtant à lui résister. Le moi glückien se dissimule derrière des masques plus ou moins opaques : des personae de la mythologie telle Perséphone auxmasques sournoisement transparents du recueil Ararat, sa voix poétique se fait plurielle mais singulière, celle d’un moi qui parle, toujours en proie au désir. Glück édifie dans chacun de ses recueils un réseau de paradigmes où la mémoire coexiste avec l’oubli, où la domesticité s’oppose à l’ailleurs hostile, où le mythe et l’ordinaire se confrontent et se confondent.Louise Glück esquive ces structures paradigmatiques à travers une poétique épurée et une ponctuation qui obscurcissent et diffèrent le sens jusqu’à l’éluder. L’entre-deux que son oeuvre explore forme à la fois un interstice et une béance : ce peut être la fissure d’Averno, la crevasse du deux-points ou le silence de Dieu dans The Wild Iris ; le milieu qui nous sépare de l’autre et de nous-mêmes et qui, simultanément, nous lie inextricablement à eux. Nous appelons ce milieu pluriel le neutre, concept que nous devons à Roland Barthes qui lui a consacré un cours au Collège de France en 1977-1978. Nous nous sommes inspirés de son approche pour lire la poésie de Glück, dont les personae sont habitées par un désir qui est, chez le poète, un désir d’écriture pour surseoir à la mort : un désir de neutre. / For forty years now, Louise Glück has been a major figure in contemporary American poetry, particularly because her poems shun the obvious and the lyric genres as we know them. If her poetry give the feminine to read, her work resists and endures it as a genre. The various masks the poet puts on may often seem transparent, but the poetic voice remains that of a persona, be it Persephone or even the ones in Ararat, her most life-inspired collection. Many and different are the faces to people her work, but behind the mask, Glück’s remains unique: her voice can be described as Dickinsonian in its bareness and subversive imagery: disguised as a desiring I, the impersonal threatens. Throughout her work, Glück has drawn a web of paradigmatic oppositions, only to be ‘baffled’: memory coexists with oblivion, the safe and cozy home is opposed to the dangerous outside world, the mythic and the mundane are intertwined in Meadowlands.Louise Glück evades and outplays the paradigm thanks to a bare language and a choice of punctuation, which darken and delay meaning to the extent of eluding it. Her poems explore an inbetweenness, which assumes the shape of a Freudian rift in Persephone’s soul, or of God’s silence to His creatures’s prayers in The Wild Iris. We are naming such in-betweenness the Neutral, a theory the French literary theorist and semiotician Roland Barthes exposed in a lecture course at the Collège de France in 1977-1978. The Neutral is the desire and its intensity, it is what parts us from the other and from ourselves, what intimately binds us together. Our reading of Louise Glück’s poetry was firstly inspired by Barthes’s theory. We see in her work a desire for the Neutral which translates as a desire for the poet to write, and relentlessly defer the instant of death.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-10-11T21:36:56Z No. of bitstreams: 1 LenitaDaSilvaLucioFernandes_TESE.pdf: 34327781 bytes, checksum: 331e3980ba66cf852b3fa0cd7970b923 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-10-14T23:06:00Z (GMT) No. of bitstreams: 1 LenitaDaSilvaLucioFernandes_TESE.pdf: 34327781 bytes, checksum: 331e3980ba66cf852b3fa0cd7970b923 (MD5) / Made available in DSpace on 2016-10-14T23:06:00Z (GMT). No. of bitstreams: 1 LenitaDaSilvaLucioFernandes_TESE.pdf: 34327781 bytes, checksum: 331e3980ba66cf852b3fa0cd7970b923 (MD5) Previous issue date: 2016-03-18 / As nanopart?culas s?o de grande interesse cient?fico, devido a uma ampla variedade de potenciais aplica??es nos campos da biomedicina, ?tica e eletr?nica. Muitos estudos t?m sido realizados com o objetivo de produzir part?culas polim?ricas em nano escala. A principal raz?o ? a maior propor??o de ?rea de superf?cie por volume, o que resulta em caracter?sticas espec?ficas. Tais considera??es levaram os pesquisadores a desenvolver t?cnicas para a obten??o de nanopart?culas polim?ricas com propriedades que permitem a aplica??o em diferentes ?reas. No presente trabalho, ? proposto um processo de polimeriza??o por atomiza??o aplicado a sistemas de miniemuls?o e suspens?o para a forma??o de part?culas submicrom?tricas de poli(metacrilato de metila) (PMMA) e poliestireno (PS), sob a forma de homopol?mero e copol?mero. Nesta t?cnica, um dispositivo atomizador ? utilizado como um m?todo alternativo para gerar as got?culas de mon?mero antes da dispers?o no meio reacional. Rea??es usando a t?cnica proposta foram realizadas e as part?culas de PMMA e PS obtidas por polimeriza??es em suspens?o ou miniemuls?o foram analisadas por espalhamento din?mico de luz (DLS), microscopia eletr?nica de varredura (MEV) e microscopia eletr?nica de transmiss?o (MET). Observou-se, atrav?s das an?lises de DLS, que foram obtidas part?culas polim?ricas com tamanho m?dio entre 40 e 1400 nm. J? com as an?lises de MEV e MET, foi poss?vel observar que as part?culas geralmente alcan?aram tamanhos inferiores a 200 nm e com caracter?stica morfol?gica bem definida e esf?rica. Tais resultados foram obtidos at? mesmo nas polimeriza??es em suspens?o, o que n?o ? comum de conseguir com t?cnicas convencionais. Por outro lado, a t?cnica proposta neste estudo tem demonstrado dificuldade em atingir altas concentra??es de s?lidos, sendo o valor m?ximo obtido de 130 g/L. Tal limita??o est? associada ao arraste das got?culas de mon?mero durante a atomiza??o, sendo este efeito mais pronunciado principalmente quando o mon?mero ? mais vol?til. Por esta raz?o, diferentes configura??es do sistema de polimeriza??o foram testadas com o prop?sito de melhoria dos resultados. Al?m de demonstrar que ? capaz de obter part?culas nanom?tricas, a t?cnica proposta neste trabalho parece promissora na obten??o de part?culas carreadoras, sendo, portanto, uma alternativa interessante pela facilidade de adapta??o para larga escala, diferentemente dos m?todos convencionais de produ??o de nanopart?culas polim?ricas.As nanopart?culas s?o de grande interesse cient?fico, devido a uma ampla variedade de potenciais aplica??es nos campos da biomedicina, ?tica e eletr?nica. Muitos estudos t?m sido realizados com o objetivo de produzir part?culas polim?ricas em nano escala. A principal raz?o ? a maior propor??o de ?rea de superf?cie por volume, o que resulta em caracter?sticas espec?ficas. Tais considera??es levaram os pesquisadores a desenvolver t?cnicas para a obten??o de nanopart?culas polim?ricas com As nanopart?culas s?o de grande interesse cient?fico, devido a uma ampla variedade de potenciais aplica??es nos campos da biomedicina, ?tica e eletr?nica. Muitos estudos t?m sido realizados com o objetivo de produzir part?culas polim?ricas em nano escala. A principal raz?o ? a maior propor??o de ?rea de superf?cie por volume, o que resulta em caracter?sticas espec?ficas. Tais considera??es levaram os pesquisadores a desenvolver t?cnicas para a obten??o de nanopart?culas polim?ricas com propriedades que permitem a aplica??o em diferentes ?reas. No presente trabalho, ? proposto um processo de polimeriza??o por atomiza??o aplicado a sistemas de miniemuls?o e suspens?o para a forma??o de part?culas submicrom?tricas de poli(metacrilato de metila) (PMMA) e poliestireno (PS), sob a forma de homopol?mero e copol?mero. Nesta t?cnica, um dispositivo atomizador ? utilizado como um m?todo alternativo para gerar as got?culas de mon?mero antes da dispers?o no meio reacional. Rea??es usando a t?cnica proposta foram realizadas e as part?culas de PMMA e PS obtidas por polimeriza??es em suspens?o ou miniemuls?o foram analisadas por espalhamento din?mico de luz (DLS), microscopia eletr?nica de varredura (MEV) e microscopia eletr?nica de transmiss?o (MET). Observou-se, atrav?s das an?lises de DLS, que foram obtidas part?culas polim?ricas com tamanho m?dio entre 40 e 1400 nm. J? com as an?lises de MEV e MET, foi poss?vel observar que as part?culas geralmente alcan?aram tamanhos inferiores a 200 nm e com caracter?stica morfol?gica bem definida e esf?rica. Tais resultados foram obtidos at? mesmo nas polimeriza??es em suspens?o, o que n?o ? comum de conseguir com t?cnicas convencionais. Por outro lado, a t?cnica proposta neste estudo tem demonstrado dificuldade em atingir altas concentra??es de s?lidos, sendo o valor m?ximo obtido de 130 g/L. Tal limita??o est? associada ao arraste das got?culas de mon?mero durante a atomiza??o, sendo este efeito mais pronunciado principalmente quando o mon?mero ? mais vol?til. Por esta raz?o, diferentes configura??es do sistema de polimeriza??o foram testadas com o prop?sito de melhoria dos resultados. Al?m de demonstrar que ? capaz de obter part?culas nanom?tricas, a t?cnica proposta neste trabalho parece promissora na obten??o de part?culas carreadoras, sendo, portanto, uma alternativa interessante pela facilidade de adapta??o para larga escala, diferentemente dos m?todos convencionais de produ??o de nanopart?culas polim?ricas.propriedades que permitem a aplica??o em diferentes ?reas. No presente trabalho, ? proposto um processo de polimeriza??o por atomiza??o aplicado a sistemas de miniemuls?o e suspens?o para a forma??o de part?culas submicrom?tricas de poli(metacrilato de metila) (PMMA) e poliestireno (PS), sob a forma de homopol?mero e copol?mero. Nesta t?cnica, um dispositivo atomizador ? utilizado como um m?todo alternativo para gerar as got?culas de mon?mero antes da dispers?o no meio reacional. Rea??es usando a t?cnica proposta foram realizadas e as part?culas de PMMA e PS obtidas por polimeriza??es em suspens?o ou miniemuls?o foram analisadas por espalhamento din?mico de luz (DLS), microscopia eletr?nica de varredura (MEV) e microscopia eletr?nica de transmiss?o (MET). Observou-se, atrav?s das an?lises de DLS, que foram obtidas part?culas polim?ricas com tamanho m?dio entre 40 e 1400 nm. J? com as an?lises de MEV e MET, foi poss?vel observar que as part?culas geralmente alcan?aram tamanhos inferiores a 200 nm e com caracter?stica morfol?gica bem definida e esf?rica. Tais resultados foram obtidos at? mesmo nas polimeriza??es em suspens?o, o que n?o ? comum de conseguir com t?cnicas convencionais. Por outro lado, a t?cnica proposta neste estudo tem demonstrado dificuldade em atingir altas concentra??es de s?lidos, sendo o valor m?ximo obtido de 130 g/L. Tal limita??o est? associada ao arraste das got?culas de mon?mero durante a atomiza??o, sendo este efeito mais pronunciado principalmente quando o mon?mero ? mais vol?til. Por esta raz?o, diferentes configura??es do sistema de polimeriza??o foram testadas com o prop?sito de melhoria dos resultados. Al?m de demonstrar que ? capaz de obter part?culas nanom?tricas, a t?cnica proposta neste trabalho parece promissora na obten??o de part?culas carreadoras, sendo, portanto, uma alternativa interessante pela facilidade de adapta??o para larga escala, diferentemente dos m?todos convencionais de produ??o de nanopart?culas polim?ricas. / Nanoparticles are of great scientific interest due to a wide variety of potential applications in biomedicine, optical and electronic fields. Many studies have been carried out in order to produce polymeric particles in nano scale. The main reason for this is the higher ratio of surface area per volume, which results in specific characteristics. Such considerations have driven researchers to develop techniques to obtain polymeric nanoparticles with properties that allow application in different areas. In the present work is proposed a polymerization process by atomization applied to miniemulsion and suspension systems for formation of submicron particles of poly(methyl methacrylate) (PMMA) and polystyrene (PS), in the form of homopolymer and copolymer. In this technique, a simple atomizer device is used as an alternative method to generate the monomer droplets before the dispersion in reaction medium. Reactions using the proposed technique were carried out and the particles of PMMA and PS obtained by suspension or miniemulsion polymerizations were analyzed by dynamic light scattering (DLS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It was observed through DLS analysis that polymeric particles were obtained with average size between 40 and 1400 nm. Concerning the SEM and TEM analysis, it was possible to observe that the particles generally reached sizes below 200 nm and with well-defined and spherical morphological characteristics. Such results were obtained even in the polymerizations using suspension formulations, which is not common of getting with conventional techniques. On the other hand, the proposed technique in this study has demonstrated difficulty in reaching high solid contents, being the maximum value obtained of 130 g/L. Such limitation is associated with the drag of the monomer droplets during atomization, being this effect more particularly pronounced when the monomer is more volatile. For this reason, different configurations of the polymerization system were tested for the purpose of improvement of results. Besides to demonstrate that is able to obtain polymeric nanoparticles, the technique proposed in this work looks promising in obtaining carrier particles, being, therefore, an interesting alternative by the facility of adaptation to large scale, differently of the conventional methods of polymeric nanoparticles production.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-08-10T11:35:30Z No. of bitstreams: 1 MarceloCostaTanaka_TESE.pdf: 3454444 bytes, checksum: edf6af9352bd8f01fdb4c2c515311b0d (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-08-10T16:14:19Z (GMT) No. of bitstreams: 1 MarceloCostaTanaka_TESE.pdf: 3454444 bytes, checksum: edf6af9352bd8f01fdb4c2c515311b0d (MD5) / Made available in DSpace on 2017-08-10T16:14:19Z (GMT). No. of bitstreams: 1 MarceloCostaTanaka_TESE.pdf: 3454444 bytes, checksum: edf6af9352bd8f01fdb4c2c515311b0d (MD5) Previous issue date: 2017-06-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Amortecedores que utilizam fluido magneto reol?gico s?o amplamente utilizados em aplica??es industriais, tais como no controle de vibra??es de m?quinas ferramentas e em constru??es sujeitas a abalos s?smicos, na ind?stria automobil?stica em suspens?es ativa ou semiativa, bem como sistemas de embreagens e freios, e na ?rea de biomec?nica em pr?teses inteligentes e interfaces h?pticas na qual simulam o sensoriamento t?til. Eles apresentam diversas caracter?sticas desej?veis como alta controlabilidade de for?a, baixo consumo energ?tico, estabilidade, ampla faixa operacional de temperatura, tempo de resposta r?pido e tamanho compacto. No entanto, o controle preciso desse dispositivo, devido ? sua inerente caracter?stica n?o linear, n?o pode ser facilmente obtido com os controladores lineares convencionais e at? mesmo por controladores mais robustos na aus?ncia de uma perfeita modelagem do seu comportamento din?mico. Hoje em dia, gra?as ao desenvolvimento da Teoria da Estabilidade, proposta pelo matem?tico russo Lyapunov, e com os avan?os da tecnologia computacional, as t?cnicas de controle n?o linear v?m sendo cada vez mais utilizadas. Quest?es ecol?gicas, social e econ?micas t?m levado a ind?stria automobil?stica a uma crescente demanda por metodologias e tecnologias eficientes no controle de vibra??es em suspens?es semiativas. Desta forma, este trabalho descreve o desenvolvimento de um controlador n?o linear, baseado no m?todo de controle por modos deslizantes com a inclus?o de uma estrat?gia de compensa??o utilizando a l?gica fuzzy, implementada matematicamente na din?mica do modelo de um sistema de amortecimento de um quarto de ve?culo, utilizando amortecedor magneto reol?gico. Resultados num?ricos s?o apresentados para demonstrar o desempenho do sistema de controle. / Magnetorheological (MR) dampers are widely used in industrial applications such as vibration control of machine tools and structures subject to seismic earthquakes; active or semi-active suspensions in the automotive industry, as well as clutch and brake systems; and in the biomechanics area with intelligent protheses and haptic interfaces wich simulate the tactile sensing. MR dampers feature several desirable features such as high power controllability, low power consumption, stability, wide operational temperature range, fast response time and compact size. However, the precise control of this device can not be easily obtained with conventional linear controllers even by more robust controllers in the absence of a perfect modeling of their dynamic behavior due to its inherent nonlinear characteristic. Nowadays, thanks to the development of stability theory, proposed by the Russian mathematician Lyapunov, and with advances in computational technology, nonlinear control techniques have been increasingly used. Ecological, social and economic issues have led the automotive industry to a growing demand for efficient methodologies and technologies in the control of vibrations in semiative suspensions. In this way, this work describes the development of a nonlinear controller based on the sliding mode control method with the inclusion of a fuzzy compensation scheme, mathematically implemented in the dynamics of the model of a one-quarter vehicle damping system using magnetoreological damper.

Submitted by Leticia Schettini (leticia@ufrrj.br) on 2016-09-20T12:51:17Z No. of bitstreams: 1 2009 - Maria Beatriz de Oliveira Monteiro.pdf: 6872732 bytes, checksum: c5bedd487727835e97ae3e6b493349b3 (MD5) / Made available in DSpace on 2016-09-20T12:51:17Z (GMT). No. of bitstreams: 1 2009 - Maria Beatriz de Oliveira Monteiro.pdf: 6872732 bytes, checksum: c5bedd487727835e97ae3e6b493349b3 (MD5) Previous issue date: 2009-05-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior-CAPES / In spite of the technological progresses, the understanding of the lignin structural formation is still matter of scientific investigations. This research aimed to utilize Eucalyptus urophylla S.T. Blake callus for lignin production. This callus were obtained from stems segments explants grown in culture medium added with a combination of the cytokine TDZ and the auxins acid indole-3-acetic (IAA), acid ?-naphthaleneacetic (NAA) and acid 2,4-dichlorophenoxyacetic (2,4-D). This growth regulators were utilized either alone or mixtured. For cell suspension production it was utilized callus obtained in medium culture added with 20?M IAA + 3?M TDZ, after 30 days of growth in vitro. Once the cells suspension was obtained, the lignin production was induced by four elicitors: jasmonic acid (JA), NAA, sucrose and control (without elicitor). It was used a completely randomized design with four replications. Each plot consisted of an Erlenmeyer with 125 ml of cells suspension culture. The Wiesner test confirmed the lignin presence in all treatments. In 3 of the 4 replicatons it was performed another evaluation to the production of DHPs (polymers by oxidative dehydrogenation) utilizing suspension filtrate added with H2O2, H2O2 + peroxidase and peroxidase. These new treatments were analyzed through polilignols production utilizing infrared (IR) and nuclear magnetic resonance of the hydrogen (NMR H). The suspension filtrate analysis of the 4th replication through ultraviolet (UV), IR, NMR 13C and NMR H evidenced the production of extra cellular lignin. Of this, the largest content was obtained in presence of sucrose as elicitor, followed by ANA and AJ. The cells in suspension increased the cellular wall lignin content in all treatments in relation to the control and the largest values were with the medium containing sucrose. DHPs were also analyzed utilizing as mattress the MS medium added of the same elicitors tested in the cellular suspension phase. For this, it was utilized as precursors the following alcohols: coniferyl or sinapyl, H2O2 and peroxidase; amd the analyses were done in RMN H and RMN 13C. The results showed DHPs synthesis of both coniferyl alcohol (DHP1c, DHP2c and DHP4c) and sinapyl alcohol (DHP2s). Nevertheless, It was not synthesized DHP in the treatment containing sucrose when the precursor was the coniferyl alcohol. On the other hand, when the sinapyl alcohol was the precursor, DHPs were only synthesized in the presence of ANA as elicitor. It was concluded that sucrose is an appropriate elicitor for the lignin production in cells suspension both at cellular and extra cellular level. However, this result was not observed in relation to DHP production. NAA auxin had a better functionality in the DHP2c and DHP2s formation. These results may be considered a progress in the lignification studies with the use of E. urophylla cell suspension. Once all these questions were answered and solved, it will be possible to develop E.urophylla suitable plants with better quality forest products and able to cause smaller environmental impact in the industrial processes. / Apesar dos avan?os tecnol?gicos, a compreens?o da forma??o estrutural da lignina ainda ? alvo de in?meras investiga??es cient?ficas. Esta pesquisa foi realizada com calos de Eucalyptus urophylla S.T. Blake para a produ??o de lignina. Os calos foram obtidos a partir de explantes de segmentos caulinares desenvolvidos em meios de cultura acrescidos de uma combina??o da citocinina TDZ e das auxinas ?cidos: 3-indolac?tico (AIA), ?-naftalenoac?tico (ANA) e diclorofenoxiac?tico (2,4-D), nas formas isoladas e conjugadas. Para a produ??o de c?lulas em suspens?o foram utilizados os calos formados no tratamento contendo 20?M de AIA + 3?M de TDZ, ap?s 30 dias de cultivo in vitro. Obtidas as c?lulas em suspens?o, a produ??o de lignina foi induzida empregando-se quatro elicitores: ?cido jasm?nico (AJ), ANA, sacarose e testemunha (sem o emprego de elicitores). O delineamento experimental utilizado foi o inteiramente casualizado, 4 repeti??es e um Erlenmeyer contendo 125 ml de cultura de c?lulas em suspens?o. O teste de Wiesner confirmou a presen?a de lignina, em todos os tratamentos testados. Em 3 das 4 repeti??es foram realizados subtratamentos para a produ??o de DHPs (pol?meros por desidrogena??o oxidativa) a partir do filtrado da suspens?o com H2O2, H2O2 + peroxidase e peroxidase. A an?lise desses subtratamentos foi realizada pela detec??o da produ??o de polilign?is atrav?s de raios infravermelho (IV) e resson?ncia magn?tica nuclear do hidrog?nio (RMN H). O filtrado da suspens?o da repeti??o 4 foi analisado por ultravioleta (UV), IV, RMN 13C e RMN H, sendo constatada a presen?a de lignina extracelular, com o maior teor sendo observado na presen?a do elicitor sacarose, seguido do ANA e AJ. As c?lulas em suspens?o apresentaram aumento no teor de lignina na parede celular em todos os tratamentos em rela??o ? testemunha e os maiores valores foram com o meio contendo sacarose. Foram analisadas tamb?m as DHPs tendo como colch?o o meio de cultura MS acrescido dos mesmos elicitores testados na fase de suspens?o celular. Para isto foram utilizados como precursores os ?lcoois conifer?lico ou sinap?lico, H2O2 e peroxidase, com a lignina analisada em RMN H e RMN 13C. Os resultados mostraram que houve s?ntese de DHPs do ?lcool conifer?lico (DHP1c, DHP2c e DHP4c) e do ?lcool sinap?lico (DHP2s). Porem quando se utilizou como precursor o ?lcool conifer?lico n?o foram sintetizadas DHPs no tratamento contendo sacarose como elicitor. E, quando foi utilizado como precursor o ?lcool sinap?lico, somente foram formadas DHPs na presen?a do elicitor ANA. Concluiu-se, ent?o, que a sacarose apresentou-se como um elicitor adequado para a produ??o de lignina nas c?lulas em suspens?o, tanto em n?vel celular quanto extracelular. Entretanto, isto n?o foi observado em rela??o ? produ??o de DHP. A auxina ANA teve funcionalidade maior na forma??o de DHP2c e DHP2s. Estes resultados devem ser considerados como um avan?o nos estudos de lignifica??o com a utiliza??o de c?lulas em suspens?o de E. urophylla. Quando esses questionamentos forem identificados e solucionados ser? poss?vel o desenvolvimento de novos indiv?duos desta esp?cie que conduzam ? produ??o de produtos florestais de melhor qualidade, com menor impacto ambiental nos processos industriais.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-09-12T17:27:40Z No. of bitstreams: 1 2009 - Maria Beatriz de Oliveira Monteiro.pdf: 6859044 bytes, checksum: 68c2b98ad22b807fdd1e5779b401a4aa (MD5) / Made available in DSpace on 2017-09-12T17:27:40Z (GMT). No. of bitstreams: 1 2009 - Maria Beatriz de Oliveira Monteiro.pdf: 6859044 bytes, checksum: 68c2b98ad22b807fdd1e5779b401a4aa (MD5) Previous issue date: 2009-05-29 / CAPES / In spite of the technological progresses, the understanding of the lignin structural formation is still matter of scientific investigations. This research aimed to utilize Eucalyptus urophylla S.T. Blake callus for lignin production. This callus were obtained from stems segments explants grown in culture medium added with a combination of the cytokine TDZ and the auxins acid indole-3-acetic (IAA), acid ?-naphthaleneacetic (NAA) and acid 2,4-dichlorophenoxyacetic (2,4-D). This growth regulators were utilized either alone or mixtured. For cell suspension production it was utilized callus obtained in medium culture added with 20?M IAA + 3?M TDZ, after 30 days of growth in vitro. Once the cells suspension was obtained, the lignin production was induced by four elicitors: jasmonic acid (JA), NAA, sucrose and control (without elicitor). It was used a completely randomized design with four replications. Each plot consisted of an Erlenmeyer with 125 ml of cells suspension culture. The Wiesner test confirmed the lignin presence in all treatments. In 3 of the 4 replicatons it was performed another evaluation to the production of DHPs (polymers by oxidative dehydrogenation) utilizing suspension filtrate added with H2O2, H2O2 + peroxidase and peroxidase. These new treatments were analyzed through polilignols production utilizing infrared (IR) and nuclear magnetic resonance of the hydrogen (NMR H). The suspension filtrate analysis of the 4th replication through ultraviolet (UV), IR, NMR 13C and NMR H evidenced the production of extra cellular lignin. Of this, the largest content was obtained in presence of sucrose as elicitor, followed by ANA and AJ. The cells in suspension increased the cellular wall lignin content in all treatments in relation to the control and the largest values were with the medium containing sucrose. DHPs were also analyzed utilizing as mattress the MS medium added of the same elicitors tested in the cellular suspension phase. For this, it was utilized as precursors the following alcohols: coniferyl or sinapyl, H2O2 and peroxidase; amd the analyses were done in RMN H and RMN 13C. The results showed DHPs synthesis of both coniferyl alcohol (DHP1c, DHP2c and DHP4c) and sinapyl alcohol (DHP2s). Nevertheless, It was not synthesized DHP in the treatment containing sucrose when the precursor was the coniferyl alcohol. On the other hand, when the sinapyl alcohol was the precursor, DHPs were only synthesized in the presence of ANA as elicitor. It was concluded that sucrose is an appropriate elicitor for the lignin production in cells suspension both at cellular and extra cellular level. However, this result was not observed in relation to DHP production. NAA auxin had a better functionality in the DHP2c and DHP2s formation. These results may be considered a progress in the lignification studies with the use of E. urophylla cell suspension. Once all these questions were answered and solved, it will be possible to develop E.urophylla suitable plants with better quality forest products and able to cause smaller environmental impact in the industrial processes. / Apesar dos avan?os tecnol?gicos, a compreens?o da forma??o estrutural da lignina ainda ? alvo de in?meras investiga??es cient?ficas. Esta pesquisa foi realizada com calos de Eucalyptus urophylla S.T. Blake para a produ??o de lignina. Os calos foram obtidos a partir de explantes de segmentos caulinares desenvolvidos em meios de cultura acrescidos de uma combina??o da citocinina TDZ e das auxinas ?cidos: 3-indolac?tico (AIA), ?-naftalenoac?tico (ANA) e diclorofenoxiac?tico (2,4-D), nas formas isoladas e conjugadas. Para a produ??o de c?lulas em suspens?o foram utilizados os calos formados no tratamento contendo 20?M de AIA + 3?M de TDZ, ap?s 30 dias de cultivo in vitro. Obtidas as c?lulas em suspens?o, a produ??o de lignina foi induzida empregando-se quatro elicitores: ?cido jasm?nico (AJ), ANA, sacarose e testemunha (sem o emprego de elicitores). O delineamento experimental utilizado foi o inteiramente casualizado, 4 repeti??es e um Erlenmeyer contendo 125 ml de cultura de c?lulas em suspens?o. O teste de Wiesner confirmou a presen?a de lignina, em todos os tratamentos testados. Em 3 das 4 repeti??es foram realizados subtratamentos para a produ??o de DHPs (pol?meros por desidrogena??o oxidativa) a partir do filtrado da suspens?o com H2O2, H2O2 + peroxidase e peroxidase. A an?lise desses subtratamentos foi realizada pela detec??o da produ??o de polilign?is atrav?s de raios infravermelho (IV) e resson?ncia magn?tica nuclear do hidrog?nio (RMN H). O filtrado da suspens?o da repeti??o 4 foi analisado por ultravioleta (UV), IV, RMN 13C e RMN H, sendo constatada a presen?a de lignina extracelular, com o maior teor sendo observado na presen?a do elicitor sacarose, seguido do ANA e AJ. As c?lulas em suspens?o apresentaram aumento no teor de lignina na parede celular em todos os tratamentos em rela??o ? testemunha e os maiores valores foram com o meio contendo sacarose. Foram analisadas tamb?m as DHPs tendo como colch?o o meio de cultura MS acrescido dos mesmos elicitores testados na fase de suspens?o celular. Para isto foram utilizados como precursores os ?lcoois conifer?lico ou sinap?lico, H2O2 e peroxidase, com a lignina analisada em RMN H e RMN 13C. Os resultados mostraram que houve s?ntese de DHPs do ?lcool conifer?lico (DHP1c, DHP2c e DHP4c) e do ?lcool sinap?lico (DHP2s). Porem quando se utilizou como precursor o ?lcool conifer?lico n?o foram sintetizadas DHPs no tratamento contendo sacarose como elicitor. E, quando foi utilizado como precursor o ?lcool sinap?lico, somente foram formadas DHPs na presen?a do elicitor ANA. Concluiu-se, ent?o, que a sacarose apresentou-se como um elicitor adequado para a produ??o de lignina nas c?lulas em suspens?o, tanto em n?vel celular quanto extracelular. Entretanto, isto n?o foi observado em rela??o ? produ??o de DHP. A auxina ANA teve funcionalidade maior na forma??o de DHP2c e DHP2s. Estes resultados devem ser considerados como um avan?o nos estudos de lignifica??o com a utiliza??o de c?lulas em suspens?o de E. urophylla. Quando esses questionamentos forem identificados e solucionados ser? poss?vel o desenvolvimento de novos indiv?duos desta esp?cie que conduzam ? produ??o de produtos florestais de melhor qualidade, com menor impacto ambiental nos processos industriais.

L’éthique et poétique de l’évolution qui est au centre de cette recherche, s’impose comme une loi native du processus de la création artistique. Elle est en effet, une « origine obligée » pour les justes survie et évolution de la voix poétique. Cette loi se fonde sur le « Rien » (qui est le savoir initiatique commun de la certitude de l’ignorance et de la vérité de la limite et de l’illimité que l’homme doit nécessairement attester dans l’instant central de l’évolution de l’esprit, afin de maintenir la survie et l’évolution de sa quête du savoir. Philippe Jaccottet définit d’emblée ce Rien comme étant le point de départ imposé de sa voix poétique dans son expérience du savoir et de la connaissance qui se mène aussi nécessairement par l’outil de recherche natif du doute et de l’incertitude : « L’incertitude est le moteur » La constante restitution du Rien se définit donc ainsi comme une nécessité vitale aux justes survie et évolution de l’oeuvre et comme une éthique de l’activité poétique et de recherche : « c’était pourtant comme la lampe sur la table avec le pain »L’expérience du savoir, en tant qu’activité vitale, détermine donc d’emblée le juste statut de -témoin de ce savoir- du poète et de l’homme. Le processus ou procès de la recherche se définissent donc ainsi en essence comme une affaire de justesse de témoignage et de justice à rendre au savoir. En effet, le lecteur en quête du savoir se retrouve face à différents témoignages véridiques et mensongers de ce savoir et face à la nécessaire activité d’épuration du paysage artistique de tout ce qui est nuisible à ses justes survie et évolution : « La difficulté n’est pas d’écrire, mais de vivre de telle manière que l’écrit naisse naturellement […] Poésie comme épanouissement, floraison, ou rien. Tout l’art du monde ne saurait dissimuler ce rien » Afin d’être un lecteur averti, le « Laveur de vaisselle » doit constamment faire sa propre expérience du savoir, ce qui est pour son esprit l’unique garant de sa juste survie et évolution et de son existence: « Je marche faute de lieu, je parle faute de savoir, preuve que je ne suis pas encore mort […] Toute poésie est la voix donnée à la mort » / [néant]

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-05-31T20:39:36Z No. of bitstreams: 1 IrisUcellaDeMedeiros_TESE.pdf: 1627038 bytes, checksum: abacbae1a6fa2f0ce88c897b540dedc4 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-06-03T00:28:56Z (GMT) No. of bitstreams: 1 IrisUcellaDeMedeiros_TESE.pdf: 1627038 bytes, checksum: abacbae1a6fa2f0ce88c897b540dedc4 (MD5) / Made available in DSpace on 2016-06-03T00:28:56Z (GMT). No. of bitstreams: 1 IrisUcellaDeMedeiros_TESE.pdf: 1627038 bytes, checksum: abacbae1a6fa2f0ce88c897b540dedc4 (MD5) Previous issue date: 2015-08-14 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Durante as ?ltimas d?cadas t?m sido demonstrado que existe uma rela??o entre a depress?o maior e a ativa??o do sistema imunol?gico. Nociceptina/orfanina FQ (N/OFQ) ? o ligante natural do receptor acoplado ? prote?na Gi chamado NOP, ambos constituem um sistema pept?dico que est? envolvido na regula??o do humor e de respostas inflamat?rias. Considerando essas a??es, a presente tese teve como objetivo investigar as consequ?ncias do bloqueio da sinaliza??o do receptor NOP nos comportamentos doentio e do tipo depressivo induzidos pela administra??o de lipopolissacar?deo (LPS) em camundongos. A administra??o sist?mica de doses de LPS, que n?o causam sepse, induzem altera??es nos comportamentos de camundongos relacionadas com a atividade das citocinas pr?-inflamat?rias fator de necrose tumoral-? (TNF-?) e interleucinas 6 (IL-6) e 1? (IL- 1 ?). Ap?s 2 a 6 h e 24 h da inje??o intraperitoneal, camundongos tratados com LPS apresentam, respectivamente, o comportamento doentio e o comportamento do tipo depressivo. No presente trabalho, a administra??o de LPS (0,8 mg/kg, ip) induziu sinais de doen?a em camundongos Swiss e CD-1, como perda de peso, redu??o transit?ria da temperatura retal e diminui??o da ingest?o de ra??o e ?gua. Al?m disso, nas 24 h ap?s a inje??o de LPS, essas mesmas linhagens de camundongos mostraram aumento no tempo de imobilidade durante os 6 min que foram submetidos ao teste de suspens?o pela cauda (TSC). O tratamento com nortriptilina (30 mg/kg, ip, 60 minutos antes do TSC) reduziu o tempo de imobilidade dos camundongos controle e tratados com LPS, e foi utilizado como antidepressivo padr?o. A administra??o pr?via ao LPS do antagonista do receptor NOP SB-612111 (10 mg/kg, ip), n?o alterou os comportamento doentio e do tipo depressivo induzidos pelatoxina. No entanto, quando injetado 24 h ap?s o tratamento com LPS, SB-612111 (ip, 30 minutos antes do TSC), como tamb?m o antagonista pept?dico do receptor NOP UFP-101 (10 nmol/2ul, icv, 5 min antes do TSC), inverteram significativamente os efeitos da toxina. O protocolo de indu??o do comportamento do tipo depressivo pela administra??o intraperitoneal de LPS tamb?m foi testado em camundongos nocautes para o receptor NOP (NOP(-/-)) e seus respectivos wild types (NOP(+/+)). O tratamento com LPS provocou altera??es significativas, como a redu??o tempor?ria da temperatura retal nos camundongos NOP(-/-) e perda de peso corporal e redu??o no consumo de ra??o e ?gua em ambos os camundongos NOP(+/+) e NOP(-/-). O consumo de ?gua foi significativamente diferente entre os gen?tipos. A inje??o de LPS induziu altera??es transit?rias nas citocinas pr?-inflamat?rias. Nas 6 horas ap?s o tratamento com LPS, os n?veis s?ricos de TNF-? mostraram-se aumentados significativamente nos camundongos NOP (+/+) e NOP (-/-), j? os n?veis de IL-6 mostraram-se significativamente aumentados apenas no soro dos camundongos NOP (+/+). Nas 24 horas ap?s a inje??o de LPS, os n?veis s?ricos das citocinas pr?-inflamat?rias retornaram ? linha de base. O tratamento com LPS provocou efeitos de tipo depressivo nos camundongos NOP (+/+), mas foi ineficaz nos camundongos NOP (-/-). Os dados obtidos nesta tese mostram que o bloqueio farmacol?gico e gen?tico da sinaliza??o mediada pelo receptor NOP n?o previne os comportamentos doentio e do tipo depressivo induzidos por LPS, no entanto revertem o comportamento do tipo depressivo. Em conclus?o, esses resultados evidenciam o envolvimento do sistema pept?dico N/OFQ - receptor NOP na modula??o dos comportamentos relacionados ao humor e ? ativa??o do sistema imunol?gico. / During the last decades, it has been established that there is a relationship between major depression and activation of immune system. Nociceptin/orphanin FQ (N/OFQ) is the natural ligand of a Gi-protein coupled receptor named NOP, both compose the peptidergic system wich is involved in the regulation of mood states and inflammatory responses. Considering these actions, the present thesis aimed to investigate the consequences of blocking NOP signaling in lipopolysaccharide (LPS)-induced sickness and depressive-like behaviors in mice. Systemic administration of LPS doses, that do not cause sepsis in mice, induce changes in their behaviors related with activity of pro-inflammatory cytokines tumor necrosis factor-? (TNF-?) and interleukins 6 (IL-6) and 1? (IL-1 ?). At the time points of 2 to 6 h and 24 h after intraperitoneal injection, mice treated with LPS displayed, respectively, sickness and depressive-like behaviors. In the present work the administration of LPS 0.8 mg/kg (ip) significantly induced sickness signs in Swiss and CD-1 mice, such as weight loss, transient reduction in rectal temperature and decrease of food and water intake. Moreover at 24 h after LPS injection these same mice strains displayed significantly increased immobility time on the tail suspension test (TST) when compared with control mice, this alteration was not related with possible locomotion impairments as verified on the open field test. Treatment with Nortriptyline 30 mg/kg (ip, 60 min prior the TST) reduced the immobility time of control and LPS-treated mice and was used as standard antidepressant. The NOP receptor antagonist SB-612111 (10 mg/kg, ip), 30 min prior LPS, did not modify LPS-induced sickness signs and depressive-like behavior. However, when injected 24 h after LPS treatment, SB-612111 (ip, 30 min prior the TST) as well as the peptidergic NOP receptor antagonist UFP-101 (10 nmol/2?L, icv, 5 min prior the TST) significantly reversed the toxin effects. The protocol of LPS-induced depressive-like states was also tested in NOP receptor knockout mice (NOP(-/-)) and their respective wild types (NOP(+/+)). LPS evoked transient rectal temperature reduction in NOP(-/-) mice and loss of body weight, food and water intake reduction in both NOP(+/+) and NOP(-/-) mice. The consumption of water was significantly different due to the genotype. LPS injection induced transient changes in pro-inflammatory cytokines. At 6 h after LPS injection, serum levels of TNF-? were significantly increased in NOP(+/+) and NOP(-/-) mice, as the IL-6 levels were significantly increased just in NOP(+/+) serum. At 24 h after LPS treatment the pro-inflammatory cytokines had returned to the baseline levels in both genotypes. LPS treatment elicited depressive-like effects in NOP(+/+) but not in NOP(-/-) mice. The data obtained during the execution of this doctoral thesis reveal that pharmacological and genetic blockade of NOP signaling does not affect LPS evoked sickness signs while reversing depressive-like behavior. In conclusion, these results highlight the involvement of the peptidergic system N/OFQ - NOP receptor in the modulation of behaviors related to mood and activation of the immune system.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-03-17T19:34:43Z No. of bitstreams: 1 SaidGoncalvesDaCruzFonseca_TESE.pdf: 3943199 bytes, checksum: b6604feae27ec3db3b6955b193bae174 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-18T00:21:30Z (GMT) No. of bitstreams: 1 SaidGoncalvesDaCruzFonseca_TESE.pdf: 3943199 bytes, checksum: b6604feae27ec3db3b6955b193bae174 (MD5) / Made available in DSpace on 2017-03-18T00:21:30Z (GMT). No. of bitstreams: 1 SaidGoncalvesDaCruzFonseca_TESE.pdf: 3943199 bytes, checksum: b6604feae27ec3db3b6955b193bae174 (MD5) Previous issue date: 2015-12-07 / A disponibilidade de formula??o pedi?trica para tratamento de tuberculose ? uma realidade para os pa?ses da ?sia e da ?frica, mas ainda n?o ocorre em outros pa?ses que apresentam consider?vel incid?ncia dessa enfermidade. Considerando a situa??o da necessidade global por medicamentos para uso em pediatria e especificamente por este tipo de produto para o tratamento da tuberculose, cuja associa??o de ativos representa um grande desafio, esse trabalho teve como objetivo o desenvolvimento de formula??es orais contendo rifampicina, isoniazida e pirazinamida em dose fixa combinada para uso em pediatria. Iniciouse com a caracteriza??o f?sico-qu?mica dos insumos ativos (identifica??o por IV, UV e CLAE, determina??o do teor por CLAE e UV, densidade aparente e ?ngulo de repouso). Em seguida foi realizada a avalia??o da compatibilidade t?rmica dos insumos ativos com diferentes excipientes (DSC e TG); o desenvolvimento de ve?culo voltado para o emprego como carreador de f?rmacos para uso oral em pediatria com o m?nimo de componentes, em baixas concentra??es, selecionando-os dentre os insumos considerados seguros para crian?as (avaliando viscosidade, pH, palatabilidade, estabilidade f?sica e microbiol?gica). Foi desenvolvida e validada metodologia anal?tica espectrofotom?trica para uso no doseamento e perfil de dissolu??o concomitante dos tr?s f?rmacos nos produtos desenvolvidos, al?m de estudos de pr?-formula??o atrav?s da densidade aparente e ?ngulo de repouso dos f?rmacos isolados e das suas misturas com aerosil, granula??o com diferentes pol?meros e seu efeito na libera??o da rifampicina, estabilidade da rifampicina em fun??o do pH, revestimento e microencapsula??o da rifampicina com quitosana, at? finalmente o desenvolvimento das formula??es s?lidas orais sob a forma de p? para reconstitui??o e comprimido dispers?vel contendo dose fixa combinada dos f?rmacos supra-citados. Foram avaliados a viscosidade, pH, teor dos f?rmacos e estabilidade das prepara??es reconstitu?das, bem como peso m?dio, dureza, tempo de desintegra??o, perfil de dissolu??o e friabilidade dos comprimidos. O m?todo de Ozawa foi empregado em estudos cin?ticos de DSC para estimar o fator de frequ?ncia, a energia de ativa??o e a ordem das rea??es que levam ? degrada??o das formas farmac?uticas s?lidas. As duas formas farmac?uticas s?lidas quando dispersas em ?gua, resultaram em suspens?o pseudo-pl?stica f?cil de ser manuseada, medida e administrada, e que podem ser utilizadas por at? 12 horas ap?s a reconstitui??o. / The availability of pediatric formulation for treating tuberculosis is a reality for the countries of Asia and Africa, but not in other countries that have considerable incidence of this disease. Considering the situation of the global need for medicines for pediatric use and specifically for this type of product for the treatment of tuberculosis, whose drugs association represents a major challenge, this study aimed to develop oral formulations containing rifampicin, isoniazid and pyrazinamide in fixed-dose combination for pediatric use. It began with the physico-chemical characterization of active ingredients (identification by IR, UV and HPLC, determination of content by HPLC and UV, bulk density and angle of repose). It then carried the evaluation of thermal compatibility of active ingredients with different excipients (DSC and TG); the vehicle development for use as a carrier of oral drugs in children with minimal components, at low concentrations, selecting them from the inputs considered safe for children (evaluating viscosity, pH, palatability, physical and microbiological stability). It was developed and validated spectrophotometric analytical methodology for use in the assay and dissolution profile of three drugs in the developed products, in addition to pre-formulation studies by apparent density and angle of repose of the individual drugs and their mixtures with aerosil, granulation with different polymers and their effect on the release of rifampicin, rifampicin stability in function of pH, coating and microencapsulation of rifampicin with chitosan, and finally the development of solid oral formulations in the form of powder for reconstitution and dispersible tablet containing a fixed-dose combination of rifampicin, isoniazid and pyrazinamide. We evaluated the viscosity, pH, content of drug and stability of the reconstituted preparations, as well as average weight, hardness, disintegration time, dissolution profile and friability of the tablets. The Ozawa method was used for DSC studies kinetic to estimate the frequency factor, the activation energy and the order of reactions that lead to degradation of solid dosage forms. The two solid dosage forms when dispersed in water, resulting in pseudo-plastic suspension easy to be handled, measured and administered, and can be used for up to 12 hours after reconstitution.

Cette thèse se propose de relire l’œuvre de J. D. Salinger à la lumière de l'usage que fait l'écrivain des motifs du détour et du suspens, tous deux caractérisés par un fonctionnement ambivalent. L'écriture de Salinger, fondamentalement introspective, prend par bien des aspects des allures de quête, à la fois identitaire et littéraire. L'exploration de l'identité qu'elle met en scène implique notamment un détour par l'altérité, auteur et personnages revêtant un certain nombre de masques, au risque parfois de refuser de s'en défaire ensuite. L'auteur se devine également derrière ses pratiques d'écriture, dont la dimension obsessionnelle révèle un profond désir de maîtrise de son travail, qui l'amène parfois à se perdre dans ses textes et s'apparente finalement davantage à une attitude de fuite qu'à la recherche d'un idéal littéraire. Dans l’œuvre salingerienne, le détour participe d'une réflexion sur les concepts de norme et de déviance, ainsi que sur le thème de l'errance. D'abord perçu comme néfaste, il apparaît à terme comme un moyen privilégié d'accéder à des révélations insoupçonnées. L’éloge de l'écart que l'on observe sur le plan thématique trouve un écho dans l'utilisation par les personnages-narrateurs de stratégies narratives louant les mérites du détour. La digression, le fragment, le renvoi aux marges du texte ainsi que l'intertextualité – autant d'outils interrogeant la distinction généralement établie entre le centre et la périphérie, entre l'accessoire et l'essentiel – révèlent toute leur efficacité lorsqu'ils sont employés pour aborder des sujets qui échappent aux cadres traditionnels. Le décentrement du texte passe également dans certains cas par un recours à la métatextualité qui permet notamment à l'écrivain de prolonger et de mettre en scène la réflexion qu'il mène sur son écriture. Les encarts métatextuels, parce qu'ils viennent interrompre temporairement la narration, peuvent aussi être considérés comme des manifestations du suspens dans le texte, suspens d'abord employé par Salinger pour interroger les notions de progression et de stase. Son œuvre présente simultanément une réflexion sur la résistance au passage du temps et la notion d'entre-deux, l'auteur affectionnant particulièrement la représentation de périodes liminales, à la fois lieux du mouvement et lieux hors du temps. Par ailleurs, l'écrivain s'attache par diverses stratégies narratives déployées dans ses textes à suspendre l’interprétation du sens, qui se révèle mouvant, différé, voire tout simplement retenu, lorsqu'il ne s'abîme pas dans l'absurde ou le non-sens. Ce faisant, Salinger interroge la validité de toute interprétation, plaidant pour une approche plus intuitive de l'art, et s'efforce du même geste de repousser indéfiniment l'achèvement de son œuvre, trahissant par là l'urgence éprouvée de mettre à distance l'angoisse mortifère qui l'obsède. / The aim of this PhD research is to try to shed new light on J. D. Salinger's work by focusing on the writer's use of two inherently ambivalent motifs, namely detour and suspension. Salinger's writing, partly because of its introspective nature, often takes on the appearance of a quest, both personal and artistic. It stages the author's exploration of his own identity, which implies exploring otherness through the use of masks worn by both characters and writer, who sometimes refuse to later put them down. The study of Salinger's writing practices shows an obsessional dimension indicative of his powerful desire to control every aspect of his work, sometimes leading him to fully immerse himself in the world of fiction – an attitude in the end more evocative of evasion than of a search for literary perfection. In Salinger's work, the representation of detours is the starting point of a reflection on the concepts of norm and deviance, as well as on the theme of wandering. While it first appears as harmful, the detour motif eventually shows its potential for the revelation of unsuspected truths. Deviation is thus presented in a positive light, and its effectiveness as a writing strategy is repeatedly praised. Such stylistic devices as digression, fragmentation, or intertextuality are called upon to question the classical distinction between center and margins, between what is essential and what is incidental. Those devices are most effective when it comes to dealing with topics unfit for traditional approaches. The author’s will to decenter the text also involves the use of metatextuality, which serves the writer's exploration of his own writing and its staging for the reader's benefit. Metatextual passages, as they temporarily bring the narration to a halt, may also be seen as manifestations of suspension. In his work, Salinger first uses suspension to question the notions of progress and stasis. His texts invite the reader to engage in a reflection on the characters' resistance to the passing of time as well as the notion of in-betweenness. Indeed, the author has specialized in the depiction of those liminal periods in the lives of individuals, which are characterized by change and an out-of-time quality. Moreover, the writer makes use of different stylistic devices to suspend the reader’s access to the meaning of his stories. In most of them meaning remains unstable and unsure, whether elucidation is deferred or simply refused to the reader, who is also confronted to manifestations of the absurd or even utter nonsense. Salinger thus challenges the value of interpretation, pleading for a more intuitive approach to art, and makes sure he indefinitely postpones the completion of his own work, in the same way that his characters develop strategies to postpone their confrontation with death.