Submitted by Filipe dos Santos (fsantos@pucsp.br) on 2016-09-01T14:33:58Z No. of bitstreams: 1 Lígia Baruch de Figueiredo.pdf: 1298049 bytes, checksum: 781f6aa407bcee4b9c0d711e3eacf7ef (MD5) / Made available in DSpace on 2016-09-01T14:33:58Z (GMT). No. of bitstreams: 1 Lígia Baruch de Figueiredo.pdf: 1298049 bytes, checksum: 781f6aa407bcee4b9c0d711e3eacf7ef (MD5) Previous issue date: 2016-04-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The overall objective of this Thesis was to understand the use unmarried adult women (single, widowed or separated) are doing of partner search applications. The theoretical contributions were the critical studies of gender and the theory of romantic attachment. The method was qualitative and the instrument used was the interview. Semi-directed interviews were conducted with five women over 35 years of urban middle class with high educational levels and adepts of new technologies, which reported their experiences of the use and their perceptions about the impact of applications of meetings in the contemporary relationships. The results led to the formulation of a proposal for three styles of usage of applications partner search: the curious use, recreational use and rational use. As for the impact on the formation of romantic relationships we observed that these widen the possibilities for meetings for different purposes. Applications for meetings also highlighted some aspects of contemporary romantic relationships, such as greater exposure, quantity and speed interactions, persistent romantic ideas updated through adaptations, and belief in technology, rationality and self-knowledge for a better partner selection. The dating applications are valid resources and increasingly popular in searching loving partnership. In general its uses reflect the typified behaviors of gender of our society, but also they facilitate the emergence of more recreational female sexual behaviors, which can contribute for greater equality between genders / O objetivo geral desta Tese foi compreender o uso que mulheres adultas não casadas (solteiras, viúvas ou separadas) estão fazendo de aplicativos de busca de parceiros. Os aportes teóricos foram os estudos críticos de gênero e a teoria do apego romântico. O método foi qualitativo e o instrumento utilizado foi a entrevista. Foram realizadas entrevistas semi-dirigidas com cinco mulheres acima dos 35 anos das camadas médias urbanas, com altos níveis educacionais e adeptas das novas tecnologias, que relataram suas experiências de uso e suas percepções a respeito do impacto dos aplicativos para encontros nos relacionamentos contemporâneos. Os resultados levaram à formulação de uma proposta de três estilos de uso dos aplicativos para busca de parceiros: o uso curioso, o uso recreativo e o uso racional. Quanto ao impacto na formação dos relacionamentos amorosos observamos que os aplicativos ampliam as possibilidades de encontros para diferentes propósitos. Os aplicativos para encontros também colocam em destaque alguns aspectos dos relacionamentos amorosos contemporâneos, tais como: maior exposição, quantidade e velocidade nas interações, ideias românticas persistentes e atualizadas por meio de adaptações e crença na tecnologia, na racionalidade e no autoconhecimento para uma melhor seleção de parceiro. Os aplicativos de encontros são recursos válidos e cada vez mais populares para a busca de parceria amorosa. De maneira geral seus usos refletem os comportamentos tipificados de gênero da nossa sociedade, mas também facilitam a emergência de comportamentos sexuais femininos mais recreativos, o que pode contribuir para uma maior equidade entre os gêneros

L’oxydase de l’acide 1-AminoCyclopropane Carboxylique (ACC Oxydase, ACCO) catalyse la formation de l’éthylène, hormone essentielle à la vie des plantes. L’ACCO catalyse l’oxydation de l’ACC en éthylène en présence de dioxygène et de deux électrons (fournis in vitro par l’ascorbate). L'activité de l'enzyme requière également, pour des raisons encore incomprises, la présence de CO2 sous la forme d'ions bicarbonates. Il s’agit d’une enzyme qui contient un ion fer(II) dans un environnement non-hémique au site actif. Etant donné l’importance de l’éthylène chez les plantes, l’ACCO, ainsi que les autres enzymes impliquées dans sa biosynthèse, ont été très étudiées durant les vingt dernières années. Cependant, peu d’études ont porté sur le rôle de l’ion métallique et le mécanisme d’action ou sur les surprenants processus d’inactivation subis par l’enzyme. L’ACCO est en effet une enzyme connue pour son instabilité. Nous avons tout d’abord entrepris une caractérisation physicochimique et biochimique de l’enzyme. Le matériel protéique utilisé a tout d’abord été analysé une coupure entre les résidus Ala 290 et Gly 291 a été observée au cours de la purification de l'enzyme. Puis, grâce à l'utilisation de techniques spectroscopiques, nous avons cherché à obtenir plus d'informations sur la fixation des substrats/cofacteurs au site actif. Enfin l’étude des mutants et des complexes modèles de l’ACCO a été réalisée afin de mieux comprendre le mécanisme catalytique et de rechercher de nouvelles activités. Nous nous sommes aussi intéressés aux mécanismes d’inactivation de l’ACCO. En présence des effecteurs en excès, cette inactivation se traduit par une fragmentation et une modification de charge. Lorsque la concentration en fer est limitée, aucune modification physique de l’enzyme inactive n’est observée et l'enzyme garde un contenu global en aminoacide et une conformation tridimensionnelle intègres. Des processus oxydatifs se déroulant directement au site actif de l’enzyme sont susceptibles d’engendrer une telle perte d’activité par l'oxydation d'un nombre limité d'acides aminés. Des études en spectrométrie de masse ont été entreprises et sont toujours en cours afin d'identifier les modifications responsables de la perte d'activité de l'enzyme.Enfin nous avons recherché d’éventuelles partenaires protéiques qui pourraient conférer à l’ACCO une meilleure stabilité. Des études préliminaires ont été entreprises et des données de microscopie suggèrent que l'ACCO est localisée près des membranes de la vacuole. / The 1-AminoCyclopropane Carboxylic acid oxidase (ACC Oxidase, ACCO) catalyzes the last step of the biosynthesis of the plant hormone, ethylene. ACCO catalyzes the oxidation of ACC into ethylene in the presence of dioxygen and two electrons (provided in vitro by ascorbate). Carbon dioxide (or bicarbonate ions) are also required for optimum activity. ACCO is an non-heme iron(II) containing enzyme. Given the importance of ethylene in plants, studies on ACCO, as well as on the other enzymes involved in its biosynthesis, have attracted much attention in the past two decades. However, few studies focus on the role of the metal ion and on the catalytic mechanism or the intriguing inactivation processes. ACCO is indeed known for its instability. We first purified and characterised the enzyme. During the purification, a cleavage between residues Ala 290 and Gly 291 was observed. Then, using spectroscopic techniques, we intended to get more information on cofactor's binding in the active site. Finally studies of mutants and model complexes of ACCO were performed in order to get a better understanding of the catalytic mechanism and to look for new activities.We were also interested in the inactivation processes of ACCO. In the presence of an excess of effectors, this inactivation resulted in fragmentation and in pI modification. When the concentration of iron is limited, no modifications of the inactive enzyme were observed. The inactive enzyme maintained its amino acid content and three-dimensional conformation. The loss of activity is therefore likely to derive from oxidative processes directly at the active site. Mass spectrometry experiments were initiated and are still under progress. Finally we were interested in identifying possible protein partners of ACCO that could provide a better stability. Preliminary studies were thus initiated and from microscopy results, ACCO was found located close to the vacuole membrane.