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Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-07-25T23:07:30Z No. of bitstreams: 1 KahenaDeQuevedoFlorentin_DISSERT.pdf: 2361429 bytes, checksum: dc742ce59ccfacea57721d908c3a033e (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-08-04T20:32:42Z (GMT) No. of bitstreams: 1 KahenaDeQuevedoFlorentin_DISSERT.pdf: 2361429 bytes, checksum: dc742ce59ccfacea57721d908c3a033e (MD5) / Made available in DSpace on 2016-08-04T20:32:42Z (GMT). No. of bitstreams: 1 KahenaDeQuevedoFlorentin_DISSERT.pdf: 2361429 bytes, checksum: dc742ce59ccfacea57721d908c3a033e (MD5) Previous issue date: 2015-10-28 / Alginate is a linear polymer compound of D-mannuronic acid(M) linked (1 ? 4) at its epimer in C-5 of L-guluronic acid (G). An alginate was isolated and partially purified from brown seaweed D. delicatula (DYN). DYN was chemically sufated (DYS). DYS showed 22% of sulfation and the rate of total sugars was around 66 and 59% for DYN and DYS respectively. DYN DYS and showed a ratio M G of 0.86 and 1.1, respectively. IR signals at 1221cm-1 confirmed the sulfation of DYS. DYN presented anticoagulant activity about intrinsic coagulation pathway, while DYS did not alter the clotting times for aPTT and PT. DYN and DYS also showed antioxidant properties especially ferric chelation where DYN reached about 97% and the OH sequestration where both averaged 85%. In 3T3 cells, DYN indicated proliferation in 24h and 48h of incubation and no cytotoxicity. For tumor lines HeLa and b16, and DYN and DYS decreased significantly the cell viability, especially after 48 hours (about 71% of inhibition). Given the results obtained in this study, it is clear that the sulfation is not decisive for the activity of D. delicatula alginate. In general, DYS and DYN shown as potential compounds to be used pharmacologically, and also in the food industry for revealing be great antioxidant. / Marine algae are rich sources of various structural compounds which recently has been increasingly studied as a new source of bioactive substances. The alginate, as come as fucans, are considered the main acidic polysaccharides found in brown seaweed. This molecule consists a linear natural polysaccharide, non-sulfated, and presents monosaccharides: acid ?-D-mannuronic (M) and ?-L-guluronic acid (G); in a vast amount compositions and threads. Alginate has been widely applied in food and pharmaceutical industries because of its ability to retain water, forming films and gels as well as thickening, stabilizing and form emulsions. In this work we aimed to extract, structurally characterize, compare and analyze the possible pharmacological activities of native alginate molecule obtained from brown seaweed Dyctiopteris delicatula (DYN), and its chemically sulfated derivative (DYS). The alginate structure and composition molecule can be proven through chemical dosing, that showed low protein contamination and high sugar level, existence and separation of M and G blocks in the descending paper chromatography, infrared spectroscopy and nuclear magnetic resonance. Molecule sulfation was proven with sulphate dosage, resulting in 28.56% sulphate in molecule; electrophoresis, verify metachromasia with toluidine blue; and infrared spectroscopy, that showed a characteristic band at 1221cm-1 corresponding a sulfate group vibration. For the pharmacological activities the tests was: antioxidant activity, changes in cell function (MTT test) and anticoagulant test. In the antioxidant activity we observed that DYN showed better results in the kidnapping of hydroxyl radicals and ferric chelation compared to DYS, this had the best result in the total antioxidant capacity. Both showed similar activity in reducing power and the kidnapping radicals DPPH. In MTT test DYN and DYS had not proliferative and cytotoxic activity in fibroblast cells (3T3) and showed antiproliferative and cytotoxic activity in cancer cell lines HeLa and B16 melanoma. In anticoagulant assay DYN showed good activity in the intrinsic pathway of blood coagulation, and a small activity in the extrinsic pathway, in the other hand DYS showed only a very small activity in the extrinsic pathway, but cannot come to be regarded as an anticoagulant agent. From these results it can be concluded that the alginate was extracted and sulfated, revealing a potential compound to be used in the pharmaceutical industry as an anticoagulant agent, antioxidant and antitumor and the sulfation has not been conclusively important to performance in the tested pharmacological activities

Nitrogen (N) deposition has increased globally over the last 150 years and further increase is predicted for the future. Nitrogen is an important nutrient for lichens, involved in many processes in both photobiont and mycobiont.  However, N can be a stressor, causing many lichens and lichen communities to disappear with increased deposition. The objective of this thesis was to investigate the response of epiphytic lichens to increased N load. This was done by simulating an increased N deposition to lichens in a boreal forest with low background N, including both short term studies with transplanted lichens and long term studies of naturally established lichens. Alectoria sarmentosa was used as a model species for a N-sensitive lichens and Platismatia glauca as a relatively more N-tolerant lichen. Nitrogen deposition was simulated by daily spraying during the growing season with water and isotopically labeled ammonium nitrate (NH4NO3). In Paper I, I found that when N is supplied in realistic doses (equivalent to deposition of 0.6, 6, 12.5, 25 and 50 kg N ha-1), there were no significant differences in uptake of NO3- or NH4+ in either of the lichen species. The results in Paper II indicate that A. samentosa may be limited by phosphorous (P) and not N limited as expected. That study highlights the importance of P, when studying the effects of N deposition, since P can both mitigate and intensify the negative effects of N on epiphytic lichens. Paper III shows that four years of simulated N deposition caused an alteration of the epiphytic lichen community, since A. sarmentosa decreased in the highest N loads (25 and 50 kg ha-1 year-1), Bryoria spp. decreased to 12.5 kg N and higher loads and Hypogymnia physodes decreased over time for all treatments except in 12.5 kg ha-1, where it only decreased during the first treatment year and then increased after 2007.  The abundance of Platismatia glauca increased over time, independent of treatment. As hypothesized, responses to the treatments differed among species, reflecting their different N optima. In paper IV, the effects of N on carbon-based secondary compounds were studied. None of the studied species (P. glauca, A. sarmentosa, Lobaria scrobiculata and Xanthoria aureola) reduced their concentration of secondary compounds during the experimental period, but in P. glauca the concentration of all compounds were significantly lower in N treated thalli compared with control thalli. The results are consistent with a high degree of constitutive defence in three of the four studied lichens, and we conclude that all four studied lichens seem to have a robust chemical defence system despite considerable manipulation of the environmental conditions. However, we don't know if these lichens are able to keep up the high protection level over longer periods comprising a number of years when more new tissue is formed. In conclusion, long term experiments are necessary to understand lichen response to environmental changes.

Alix (ALG-2 Interacting Protein X) est une protéine cytoplasmique impliquée dans divers processus cellulaires allant de l'apoptose à la cytocinèse en passant par le bourgeonnement des virus, la réparation membranaire et la régulation de la voie endosomale. Toutes ces fonctions sont étroitement associées à l'interaction d'Alix avec ses partenaires impliqués dans la déformation des membranes telles que les endophilines A, Tsg-101 et CHMP4B du complexe ESCRT (Endosomal Sorting Complex Required for Transport). Le but de ce projet est de caractériser le phénotype de la souris Alix ko récemment développée au laboratoire, dans l'espoir de mieux comprendre le rôle physiologique d'Alix. Ces souris, viables et fertiles, sont caractérisées par une microcéphalie apparaissant au cours de l'embryogenèse. Ce phénotype est accompagné d'une apoptose massive touchant les progéniteurs neuronaux durant la neurogenèse et d'une altération du développement de l'arborisation dendritique après la naissance. Les souris adultes présentent également des défauts de plasticité synaptique accompagnés d'une altération du recyclage des vésicules synaptiques. L'ensemble de ces processus repose sur la capacité d'Alix à contrôler le remodelage de la membrane plasmique. Au niveau moléculaire, nos travaux sur les neurones en cultures et sur les fibroblastes montrent une régulation de l'endocytose indépendante de la clathrine (CIE) par Alix et les endophilines A qui pourrait être à l'origine du phénotype neuronal de la souris. Cependant, l'association d'Alix avec CHMP4B du complexe ESCRT pourrait également être nécessaire au développement du système nerveux puisque l'interaction Alix-CHMP4B est nécessaire pour le contrôle de la CIE et de la mort neuronale.L'ensemble de ces résultats mets en évidence qu'à travers des mécanismes et des partenaires bien caractérisés, Alix est requise pour de nouvelles fonctions nécessaires au développement et au fonctionnement du système nerveux. / Alix (ALG-2 Interacting Protein X) is a cytoplasmic protein implicated in multiple processes including apoptosis, endosome function, membrane repair, viral budding and cytokinesis. Most of these involve modifications of plasma or endosomal membrane organization. Consistent with this, Alix is known to interact with diverse proteins modulating membrane deformation, such as endophilins or Tsg-101 and CHMP4B of the Endosomal Sorting Complex Required for Transport (ESCRT). By studying the phenotype of Alix ko mice that we recently developed, we aim to better understand the precise role of Alix in vivo. These mice are viable and fertile but develop microcephaly even at embryonic stages. This microcephaly is associated with an increase of apoptosis in neural progenitor cells in embryos and a defect in neurite outgrowth at post-natal stages. Later on, these mice also develop defects in synaptic plasticity related to an alteration of synaptic vesicle recycling. All of these processes are tightly dependent on membrane shaping and remodelling. These features of the phenotype can be related to a new function of Alix with endophilin A in the control of clathrin-independent endocytosis (CIE), as described in Alix ko fibroblasts and cultured neurons. However, these defects might also be related to the well-known Alix partner CHMP4B, since we now know that this interaction is needed for controlling CIE and neuronal cell death.All together, these results shed light on novel functions of Alix in the developing and adult central nervous system, all relying on well-known molecular mechanisms and partners.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-03-17T19:02:40Z No. of bitstreams: 1 ClaudioAndresCallejasOlguin_TESE.pdf: 2208703 bytes, checksum: 0e72fd38176ce63ab4ad6ea3333dc84c (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-17T20:07:54Z (GMT) No. of bitstreams: 1 ClaudioAndresCallejasOlguin_TESE.pdf: 2208703 bytes, checksum: 0e72fd38176ce63ab4ad6ea3333dc84c (MD5) / Made available in DSpace on 2017-03-17T20:07:55Z (GMT). No. of bitstreams: 1 ClaudioAndresCallejasOlguin_TESE.pdf: 2208703 bytes, checksum: 0e72fd38176ce63ab4ad6ea3333dc84c (MD5) Previous issue date: 2016-07-29 / O conjunto de fun??es totais comput?veis somente tem sido estudado topologicamente como um subespa?o de um espa?o de Baire. Onde a topologia deste espa?o de Baire ? a topologia induzida de uma topologia de Scott para as fun??es parciais (n?o necessariamente comput?veis). Nesta tese constr?i-se uma topologia original no conjunto de ?ndices das fun??es totais comput?veis e demonstra-se que ela n?o ? homeomorfa com o subespa?o do espa?o de Baire que foi mencionado. H? um subconjunto indecid?vel importante no conjunto de fun??es totais comput?veis chamado ?o conjunto de fun??es comput?veis regulares?, que recebe aten??o especial nesta tese. Com a finalidade de fazer um estudo topol?gico deste conjunto constr?i-se todo um aparato te?rico. Ap?s apresentar o estado da arte da teoria dos dom?nios generalizada introduz-se uma generaliza??o original dos dom?nios alg?bricos nomeados como ?quase dom?nios alg?bricos?. Com uma ordem parcial adequada, constr?i-se um quase-dom?nio alg?brico para o conjunto de fun??es comput?veis totais. Por meio da topologia de Scott associada a esse quase-dom?nio alg?brico, obt?m-se uma condi??o necess?ria para as fun??es comput?veis regulares. Fica provado que esta ?ltima topologia n?o ? homeomorfa com o subespa?o previamente mencionado do espa?o de Baire apresentado. Como subproduto, introduz-se uma topologia de Scott para o conjunto de fun??es totais (n?o necessariamente comput?veis). Fica provado que esta ?ltima topologia n?o ? homeomorfa com o espa?o de Baire apresentado. Fica tamb?m provado que as topologias de Scott no conjunto de fun??es totais e no subconjunto de fun??es totais comput?veis t?m o conjunto de fun??es totais com suporte finito como conjunto denso comum. Analogamente, fica provado que a topologia no conjunto ?ndice do conjunto de fun??es totais comput?veis tem como conjunto denso os ?ndices correspondentes a uma enumera??o comput?vel sem repeti??o do conjunto de fun??es totais com suporte infinito. / Topologically the set of total computable functions has been studied only as a subspace of a Baire space. Where the topology of this Baire space is the induced topology of a Scott topology for the partial functions (not necessarily computable). In this thesis a novel topology on the index set of the set of total computable functions is built and proved that it is not homeomorphic to the aforementioned subspace of the presented Baire space. There is an important undecidable subset of the set of total computable functions called the set of regular computable functions that receives particular attention in this thesis. In order to make a topological study of this set a whole theoretical apparatus is constructed. After presenting the state of the art of generalised domain theory, a novel generalisation of algebraic domains coined as algebraic quasidomains is introduced. With a suited partial-order an algebraic quasi-domain is built for the set of total computable functions. Through the Scott topology associated with this algebraic quasi-domain a necessary condition for the regular computable functions is obtained. It is proved that this later topology is not homeomorphic to the previously mentioned subspace of the presented Baire space. As a byproduct a Scott topology for the set of total functions (not necessarily computable) is introduced. It is proved that this later topology is not homeomorphic to the presented Baire space. It is also proved that the Scott topologies in the set of total functions and in the subset of total computable functions have the set of total functions with finite support as a common dense set. Analogously it is proved that the topology in the index set of the set of total computable functions has as a dense set the indexes corresponding to a computable enumeration without repetition of the set of total functions with finite support.

Nowdays, when we are running out of public IPv4 addresses, we rely on techniques that at least postpone their complete exhaustion. One of these techniques is a network address translation (NAT). Internet providers require the highest possible bandwidth from devices that perform this task. This thesis compares NAT DPDK, built on top of DPDK framework, with freely available alternatives. This work also extends NAT DPDK with Application-Level Gateway support.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-03-02T23:39:14Z No. of bitstreams: 1 ThiagoNascimentoDaSilva_DISSERT.pdf: 675458 bytes, checksum: 9123812e69a846020d3cd6346e530e1e (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-03-13T18:55:45Z (GMT) No. of bitstreams: 1 ThiagoNascimentoDaSilva_DISSERT.pdf: 675458 bytes, checksum: 9123812e69a846020d3cd6346e530e1e (MD5) / Made available in DSpace on 2018-03-13T18:55:45Z (GMT). No. of bitstreams: 1 ThiagoNascimentoDaSilva_DISSERT.pdf: 675458 bytes, checksum: 9123812e69a846020d3cd6346e530e1e (MD5) Previous issue date: 2018-01-25 / Al?m da mais conhecida l?gica de Nelson (?3) e da l?gica paraconsistente de Nelson (?4), David Nelson introduziu no artigo de 1959 "Negation and separation of concepts in constructive systems", com motiva??es de aritm?tica e construtividade, a l?gica que ele chamou de "?". Naquele trabalho, a l?gica ? definida por meio de um c?lculo (que carece crucialmente da regra de contra??o) tendo infinitos esquemas de regras, e nenhuma sem?ntica ? fornecida. Neste trabalho n?s tomamos o fragmento proposicional de ?, mostrando que ele ? algebriz?vel (de fato, implicativo) no sentido de Blok & Pigozzi com respeito a uma classe de reticulados residuados involutivos. Assim, fornecemos a primeira sem?ntica para ? (que chamamos de ?-?lgebras), bem como um c?lculo estilo Hilbert finito equivalente ? apresenta??o de Nelson. Fornecemos um algoritmo para construir ?-?lgebras a partir de ?-?lgebras ou reticulados implicativos e demonstramos alguns resultados sobre a classe de ?lgebras que introduzimos. N?s tamb?m comparamos ? com outras l?gicas da fam?lia de Nelson, a saber, ?3 e ?4. / Besides the better-known Nelson logic (?3) and paraconsistent Nelson logic (?4), in Negation and separation of concepts in constructive systems (1959) David Nelson introduced a logic that he called ?, with motivations of arithmetic and constructibility. The logic was defined by means of a calculus (crucially lacking the contraction rule) having infinitely many rule schemata, and no semantics was provided for it. We look in the present dissertation at the propositional fragment of ?, showing that it is algebraizable (in fact, implicative) in the sense of Blok and Pigozzi with respect to a class of involutive residuated lattices. We thus provide the first known algebraic semantics for ?(we call them of ?-algebras) as well as a finite Hilbert-style calculus equivalent to Nelson?s presentation. We provide an algorithm to make ?-algebras from ?-algebras or implicative lattices and we prove some results about the class of algebras which we have introduced. We also compare ? with other logics of the Nelson family, that is, ?3 and ?4.