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The regular behavior of sound sources helps us to make sense of the auditory environment. Regular patterns may, for instance, convey information on the identity of a sound source (such as the acoustic signature of a train moving on the rails). Yet typically, this signature overlaps in time with signals emitted from other sound sources. It is generally assumed that auditory regularity extraction cannot operate upon this mixture of signals because it only finds regularities between adjacent sounds. In this view, the auditory environment would be grouped into separate entities by means of readily available acoustic cues such as separation in frequency and location. Regularity extraction processes would then operate upon the resulting groups. Our new experimental evidence challenges this view. We presented two interleaved sound sequences which overlapped in frequency range and shared all acoustic parameters. The sequences only differed in their underlying regular patterns. We inserted deviants into one of the sequences to probe whether the regularity was extracted. In the first experiment, we found that these deviants elicited the mismatch negativity (MMN) component. Thus the auditory system was able to find the regularity between the non-adjacent sounds. Regularity extraction was not influenced by sequence cohesiveness as manipulated by the relative duration of tones and silent inter-tone-intervals. In the second experiment, we showed that a regularity connecting non-adjacent sounds was discovered only when the intervening sequence also contained a regular pattern, but not when the intervening sounds were randomly varying. This suggests that separate regular patterns are available to the auditory system as a cue for identifying signals coming from distinct sound sources. Thus auditory regularity extraction is not necessarily confined to a processing stage after initial sound grouping, but may precede grouping when other acoustic cues are unavailable.

Adjacent precast, prestressed box beam bridges have a history of poor performance and have been observed to exhibit common types of deterioration including longitudinal cracking, concrete spalling, and deterioration of the concrete top flange. The nature of these types of deterioration leads to uncertainty of the extent and effect of deterioration on structural behavior. Due to limitations in previous research and understanding of the strength of deteriorated box beam bridges, conservative assumptions are being made for the assessment and load rating of these bridges. Furthermore, the design of new box beam bridges, which can offer an efficient and economical solution, is often discouraged due to poor past performance. Therefore, the objective of this research is to develop improved recommendations for the inspection, load rating, and design of adjacent box beam bridges. Through a series of bridge inspections, deteriorated box beams were identified and acquired for experimental testing. The extent of corrosion was determined through visual inspection, non-destructive evaluation, and destructive evaluation. Non-destructive tests (NDT) included the use of connectionless electrical pulse response analysis (CEPRA), ground penetrating radar (GPR), and half-cell potentials. The deteriorated capacity was determined through structural testing, and an analysis procedure was developed to estimate deteriorated behavior. A rehabilitation procedure was also developed to restore load transfer of adjacent beams in cases where shear key failures are suspected. Based on the understanding of deterioration developed through study of deteriorated adjacent box beam bridges, improved inspection and load rating procedure are provided along with design recommendations for the next generation of box beam bridges.

Grâce au développement de la technologie des semi-conducteurs, les ballasts électroniques fonctionnant en haute fréquence offrent des avantages considérables par rapport aux ballasts électromagnétiques conventionnels. Il en résulte une augmentation de la durée de vie de la lampe, une diminution du volume et du poids du système et surtout un meilleur contrôle de son fonctionnement afin de réduire notamment la consommation électrique. Parmi des lampes à décharge, la lampe sodium haute pression a une excellente efficacité lumineuse et une longue durée de vie. Pourtant, quand la lampe fonctionne en haut fréquence, des perturbations de type « résonance acoustique (RA) » peuvent entraîner l’instabilité de la décharge, son extinction ou pire, la destruction de la lampe. Cette thèse, intitulée « Modes d’Alimentation et de Commande des lampes sodium haute pression en vue d’éviter les résonances acoustiques », traite de plusieurs problèmes. Les caractéristiques de la décharge haute pression, le phénomène de RA, ses conditions d’excitation (notamment au travers d’un phénomène d’hystérésis original) et la variation des paramètres électriques due à la présence de résonances acoustiques dans la lampe, ont été étudiés. Les résultats sont issus de travaux de simulation et expérimentaux menés au sein du laboratoire LAPLACE. Grâce à ces acquis fondamentaux, plusieurs nouvelles méthodes d’alimentation par l’injection de signaux à fréquences proches ont été proposées dans nos travaux. Il s’agit d’éviter la résonance acoustique dans la lampe alimentée par un ballast de structure très réduite par rapport aux solutions classiques. Cette méthode est basée sur le choix judicieux des signaux injectés dans la lampe et leur répartition, (alimentation par deux, trois ou cinq signaux, répartition symétrique, asymétrique totale ou partielle). Le résultat est un meilleur étalement du spectre et donc une réduction de puissances harmoniques sélectionnées permettant de s’adapter, à terme aux conditions d’excitation des RA, mais aussi les limitations de ces méthodes compte tenu du facteur crête. Enfin, différents types de commande en boucle fermée sont proposés, ils permettent d’assurer la stabilité de la décharge et le contrôle des puissances imposées dans la lampe. Les études théoriques, en simulation et expérimentales qui ont été conduites nous ont permis d’aboutir à des résultats concluants. / For high pressure sodium (HPS) lamps, the progress of semi-conductor technology has provided considerable advantages in the design of high frequency operated electronic ballasts, compared to conventional electromagnetic ballasts. The advantages deal with lamp lifetime improvement, ballast volume and mass reduction, and particularly with a better control of lamp operation for optimized power consumption. Among discharge lamps, high pressure sodium (HPS) lamp has excellent efficacy and long lifetime. However, when it is operated at high frequency, discharge perturbation namely “acoustic resonances (AR)” can provoke some lamp arc instabilities, extinction or, even worst, lamp destruction. The present thesis, entitled “Supply and control methods for acoustic resonances avoidance in high intensity discharge lamps” deals with several matters.  High intensity discharge (HID) characteristics, AR phenomenon, its excitation conditions (including the original features of AR hysteresis) and lamp electrical parameters variation due to AR presence, will be studied. The obtained results were provided by simulations and experimentations carried out in LAPLACE laboratory. Thanks to the acquired results of previous studies, several novel lamp supply strategies via adjacent frequency signals injection were proposed. The main concepts here consist in the avoidance of AR presented in a lamp supplied by designed electronic ballast with reduced structure, compared to classical solutions. Otherwise, the presented methods are based on pertinent choices of injected signals applied to the lamp and their frequency distributions (two, three or five signals and symmetric, partial asymmetric or total asymmetric signals). The studies actually showed better spreading of signal spectrum and power harmonic amplitudes reduction adapted to AR excitation conditions, while taking into account crest factor limitation. Finally, different control laws (PI, Hysteresis, Self-oscillation, Resonant controllers) were also proposed in order to guarantee lamp discharge stabilization and power controls. The theoretical and experimental studies including simulations were conducted to reach concluding results of our works.

Made available in DSpace on 2016-01-26T12:51:47Z (GMT). No. of bitstreams: 1 fernandofilipe_dissert.pdf: 443784 bytes, checksum: bb6328cd8296f1c4b222d0c43cdafda1 (MD5) Previous issue date: 2006-02-13 / Adjacent segment disease is defined as an abnormal process developing in the adjacent level above and/or bellow the arthrodesis of the segment. It is considered a late complication of lumbar spine arthrodesis. It has been very important due to the procedures in the last years. Objective: To evaluate the risk factors associated with the disease at adjacent level as well as its relationship with the natural history of degenerative disease of the lumbar spine. Material and Methods: This was a retrospective study, from January 2000 to December 2002.Thirty-eight patients undergoing arthrodesis in the lumbosacral spine using the pedicle screw fixation participated in the study. Results: These patients had a mean follow-up of 30 months; 10 patients presented adjacent segment disease, 7 disc degeneration, 2 spinal stenosis and one discal spine hernia. The patients´ mean age was 48.5 years; female sex was the majority. Degeneration occurred in 4 patients with stenosis; 4 with spondylolisthesis, and 1 with post disc hernia; all these had been submitted to arthrodesis of lumbosacral spine. The majority was asymptomatic, after being treated by arthrodesis in multiple levels. There was no statistical difference when the above factors were related. Conclusion: Adjacent segment disease is a late complication in the arthrodesis of lumbosacral spine with no relationship of risk factors presented in this study. Therefore, its origin could be related with the natural history of the degenerative disease of lumbar spine. / A doença do nível adjacente é definida como um processo anormal que se desenvolve no nível adjacente, acima e/ou abaixo do segmento artrodesado. Considerada como uma complicação tardia da artrodese da coluna vertebral, tem-se tornado muito importante em decorrência do aumento dos procedimentos nos últimos anos. Objetivo: Avaliar os fatores de risco associados à ocorrência da doença do nível adjacente e sua relação com a história natural da doença degenerativa da coluna vertebral. Material e métodos: Análise retrospectiva de janeiro de 2000 a dezembro de 2002, realizada em 38 pacientes submetidos a artrodese de coluna lombosacra com a utilização de parafuso pedicular. Resultado: Os pacientes analisados apresentavam follow up médio de 30 meses, com a presença de 10 pacientes com doença do nível adjacente; sendo 7 com degeneração discal, 2 com estenose de canal vertebral e 1 com hérnia de disco. A idade média dos pacientes foi 48,5 anos, com predomínio no sexo feminino. A degeneração ocorreu em 4 pacientes com estenose de canal, em 4 pacientes com espondilolistese, em 1 paciente com escoliose e em 1 paciente pós hérnia de disco, os quais tinham sido submetidos a artrodese da coluna lombosacra. A maioria dos pacientes foram submetidos a artrodese em múltiplos níveis e apresentavam-se assintomáticos. Nenhuma diferença estatística foi evidenciada quando relacionados os fatores acima. Conclusão: A doença do nível adjacente é uma complicação tardia existente na artrodese de coluna lombosacra, não relacionada aos fatores de risco apresentados; portanto o seu aparecimento estaria relacionado à história natural da doença degenerativa da coluna lombar.

L'adenocarcinoma ductal de pàncrees és un càncer molt agressiu que actualment representa la quarta causa de mort per càncer als països occidentals. Les teràpies clàssiques, basades en la resecció quirúrgica, la radioteràpia i el tractament amb quimioteràpics com la gemcitabina, no són efectives en la gran majoria del pacients. En aquests darrers anys s'està estudiant l'aplicació de la teràpia gènica com a teràpia alternativa o adjuvant per al tractament d'aquesta neoplàsia. Una aproximació important és la que es basa en la transferència del gen de la timidina quinasa del virus Herpes simplex tipus 1 (TK) i l'administració de la pro-droga ganciclovir (GCV). Un dels atractius que presenta aquest sistema TK/GCV és que disposa d'un mecanisme amplificador de la mort cel·lular, que va més enllà d'eliminar la cèl·lula tumoral modificada genèticament amb el gen TK i que es coneix com l'efecte adjacent. S'ha proposat, que aquest efecte podria ser degut al trànsit dels metabòlits tòxics del GCV a través dels canals intercel·lulars que formen les unions gap.En aquesta tesi hem realitzat una caracterització de l'expressió de les molécules constitutives de les unions gap, les connexines, en l'adenocarcinoma de pàncrees; i hem estudiat el seu paper en l'eficàcia de dues estratègies terapèutiques basades en l'administració de compostos anàlegs de nucleòsids: el sistema suïcida TK/GCV i el quimioteràpic gemcitabina. S'ha estudiat també la possible contribució de l'E-cadherina, element clau de les unions adherents epitelials, en l'efecte citotòxic d'aquestes teràpies i amb especial èmfasi en el sistema TK/GCV.

Made available in DSpace on 2014-12-17T15:47:03Z (GMT). No. of bitstreams: 1 SilviaMDMM_TESE.pdf: 3010194 bytes, checksum: 43610ec3f0a30c2e5ef7fb5c0b2dc5b0 (MD5) Previous issue date: 2013-12-16 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The Quadratic Minimum Spanning Tree Problem (QMST) is a version of the Minimum Spanning Tree Problem in which, besides the traditional linear costs, there is a quadratic structure of costs. This quadratic structure models interaction effects between pairs of edges. Linear and quadratic costs are added up to constitute the total cost of the spanning tree, which must be minimized. When these interactions are restricted to adjacent edges, the problem is named Adjacent Only Quadratic Minimum Spanning Tree (AQMST). AQMST and QMST are NP-hard problems that model several problems of transport and distribution networks design. In general, AQMST arises as a more suitable model for real problems. Although, in literature, linear and quadratic costs are added, in real applications, they may be conflicting. In this case, it may be interesting to consider these costs separately. In this sense, Multiobjective Optimization provides a more realistic model for QMST and AQMST. A review of the state-of-the-art, so far, was not able to find papers regarding these problems under a biobjective point of view. Thus, the objective of this Thesis is the development of exact and heuristic algorithms for the Biobjective Adjacent Only Quadratic Spanning Tree Problem (bi-AQST). In order to do so, as theoretical foundation, other NP-hard problems directly related to bi-AQST are discussed: the QMST and AQMST problems. Bracktracking and branch-and-bound exact algorithms are proposed to the target problem of this investigation. The heuristic algorithms developed are: Pareto Local Search, Tabu Search with ejection chain, Transgenetic Algorithm, NSGA-II and a hybridization of the two last-mentioned proposals called NSTA. The proposed algorithms are compared to each other through performance analysis regarding computational experiments with instances adapted from the QMST literature. With regard to exact algorithms, the analysis considers, in particular, the execution time. In case of the heuristic algorithms, besides execution time, the quality of the generated approximation sets is evaluated. Quality indicators are used to assess such information. Appropriate statistical tools are used to measure the performance of exact and heuristic algorithms. Considering the set of instances adopted as well as the criteria of execution time and quality of the generated approximation set, the experiments showed that the Tabu Search with ejection chain approach obtained the best results and the transgenetic algorithm ranked second. The PLS algorithm obtained good quality solutions, but at a very high computational time compared to the other (meta)heuristics, getting the third place. NSTA and NSGA-II algorithms got the last positions / O problema da ?rvore Geradora M?nima Quadr?tica (AGMQ) ? uma vers?o do problema da ?rvore Geradora M?nima na qual se considera, al?m dos custos lineares tradicionais, uma estrutura de custos quadr?tica. Tal estrutura quadr?tica modela efeitos de intera??o entre pares de arestas. Os custos lineares e quadr?ticos s?o somados para compor o custo total da ?rvore geradora, que deve ser minimizado. Quando as intera??es s?o restritas ?s arestas adjacentes, o problema ? denominado ?rvore Geradora M?nima Quadr?tica em Adjac?ncia de Arestas (AGMQA). A AGMQA e a AGMQ s?o problemas NP-dif?ceis que modelam diversos problemas de projeto de redes de transporte e distribui??o. Em geral, a AGMQA emerge como um modelo mais apropriado para a modelagem de problemas reais. Embora, na literatura, os custos lineares e quadr?ticos sejam somados, em aplica??es reais, os custos linear e quadr?tico podem ser conflitantes. Neste caso, seria mais interessante considerar os custos separadamente. Neste sentido, a Otimiza??o Multiobjetivo prov? uma modelagem mais realista para os problemas da AGMQ e da AGMQA. Uma revis?o do estado da arte, at? o momento, n?o foi capaz de encontrar qualquer trabalho que investigue esses problemas sob um ponto de vista biobjetivo. O objetivo desta Tese ?, pois, o desenvolvimento de algoritmos exatos e heur?sticos para o Problema Biobjetivo da ?rvore Geradora Quadr?tica em Adjac?ncia de Arestas (AGQA-bi). Para tanto, como fundamenta??o te?rica, discutem-se outros problemas NP-dif?ceis diretamente relacionados ? AGQA-bi, a saber: AGMQ e AGMQA. Algoritmos exatos backtracking e branch-and-bound s?o propostos para o problema-alvo desta investiga??o. Os algoritmos heur?sticos desenvolvidos s?o: busca local Pareto Local Search, Busca Tabu com ejection chain, Algoritmo Transgen?tico, NSGA-II e uma hibridiza??o das duas ?ltimas propostas mencionadas denominada NSTA. Os algoritmos propostos s?o comparados entre si por meio da an?lise de seus desempenhos em experimentos computacionais com casos de teste adaptados da literatura da AGMQ. No que se refere aos algoritmos exatos, a an?lise considera, em especial, o tempo de execu??o. No caso dos algoritmos heur?sticos, al?m do tempo de execu??o, a qualidade do conjunto de aproxima??o gerado ? avaliada. Indicadores de qualidade s?o empregados para aferir tal informa??o. Ferramentas estat?sticas apropriadas s?o usadas na an?lise de desempenho dos algoritmos exatos e heur?sticos. Para o conjunto de inst?ncias utilizado e considerando os crit?rios de qualidade dos conjuntos de aproxima??o gerados e tempo de execu??o dos algoritmos, os experimentos mostraram que o algoritmo de Busca Tabu com ejection chain obteve melhores resultados e que o algoritmo transgen?tico ficou em segundo lugar. A busca local PLS obteve solu??es de qualidade, mas a um tempo computacional muito alto se comparado ?s outras (meta)heur?sticas. Nesse sentido, ocupa a terceira coloca??o. Por fim, ficaram os algoritmos NSTA e NSGAII

Promouvoir le service de contrôle biologique des bio-agresseurs des cultures nécessite de comprendre le fonctionnement des populations d’ennemis naturels dans des mosaïques agricoles qui sont hétérogènes et dynamiques. Cette thèse porte sur l’étude des déterminants de l’abondance des carabes impliqués dans la régulation des adventices via la consommation de leurs graines. L’analyse des variations d’abondance des espèces à une échelle nationale nous a permis d’évaluer le rôle relatif des facteurs locaux et paysagers et de mettre en évidence le rôle important de la proportion de colza et de prairie dans le paysage sur l’abondance de carabes consommateurs de graines dans les parcelles cultivées. Le suivi expérimental de la composition des communautés de carabes ainsi que du statut nutritionnel et des mouvements de plusieurs espèces dans des dispositifs colza/blé et colza/bordure pérenne sur l’ensemble de la période d’activité des carabes nous a permis de mettre en évidence que (i) les carabes répondent l’hétérogénéité de cette mosaïque agricole (type de culture, qualité de l’habitat au sein d’un même type de culture), avec des réponses souvent spécifiques (ii) que le colza d’hiver joue un rôle important dans le fonctionnement des populations de carabes consommateurs de graines du fait de sa haute qualité d’habitat pour ces espèces, (iii) que la variation de la qualité d’habitat peut jouer sur le mouvement des carabes vers l’habitat adjacent et (iv) que la présence d’une bordure pérenne au voisinage d’une culture favorise le maintien et le fonctionnement de plusieurs espèces consommatrices de graines d’adventices dans la mosaïque agricole. / Promoting biological pest control in crops requires to understand the functioning of natural enemies in heterogeneous and dynamic agricultural mosaics. This thesis focuses on the study of the determinants that influence the abundance of ground beetles involved in the regulation of weeds via the consumption of their seeds. In an analysis of the variations of species abundance at a national scale we identified the respective role of local and landscape factors and showed that oilseed rape and grassland proportions in the landscape were key determinants of the abundance of carabid species in cultivated fields. We then studied carabid communities through combined measured of their abundance, nutritional status and between-habitat movements, during an entire cropping season, in pairs of habitats consisting in winter oilseed rape fields with either a crop (winter cereal fields) or a semi-natural habitat (grassy field margins) as adjacent habitat. We demonstrated that (i) ground beetles respond to the heterogeneity of arable mosaic (crop type, habitat quality within the same crop type), often with specific responses, (ii) winter oilseed rape plays an important role in the functioning of weed seed-eating carabid species due to its high habitat quality, (iii) variations in habitat quality can influence the movement of beetles to the adjacent habitat and (iv) the presence of a grassy field margin in the vicinity of a crop promotes the maintenance and functioning of several species in arable mosaics.

Dans cette thèse, nous nous intéressons à différentes notions de colorations sous contraintes. Nous nous intéressons plus spécialement à la coloration acyclique, à la coloration forte d'arêtes et à la coloration d'arêtes sommets adjacents distinguants.Dans le Chapitre 2, nous avons étudié la coloration acyclique. Tout d'abord nous avons cherché à borner le nombre chromatique acyclique pour la classe des graphes de degré maximum borné. Ensuite nous nous sommes attardés sur la coloration acyclique par listes. La notion de coloration acyclique par liste des graphes planaires a été introduite par Borodin, Fon-Der Flaass, Kostochka, Raspaud et Sopena. Ils ont conjecturé que tout graphe planaire est acycliquement 5-liste coloriable. De notre côté, nous avons proposé des conditions suffisantes de 3-liste coloration acyclique des graphes planaires. Dans le Chapitre 3, nous avons étudié la coloration forte d'arêtes des graphes subcubiques en majorant l'indice chromatique fort en fonction du degré moyen maximum. Nous nous sommes également intéressés à la coloration forte d'arêtes des graphes subcubiques sans cycles de longueurs données et nous avons également obtenu une majoration optimale de l'indice chromatique fort pour la famille des graphes planaires extérieurs. Nous avons aussi présenté différents résultats de complexité pour la classe des graphes planaires subcubiques. Enfin, au Chapitre 4, nous avons abordé la coloration d'arêtes sommets adjacents distinguants en déterminant les majorations de l'indice avd-chromatique en fonction du degré moyen maximum. Notre travail s'inscrit dans la continuité de celui effectué par Wang et Wang en 2010. Plus précisément, nous nous sommes focalisés sur la famille des graphes de degré maximum au moins 5. / In this thesis, we are interested in various coloring of graphs under constraints. We study acyclic coloring, strong edge coloring and adjacent vertex-distinguishing edge coloring.In Chapter 2, we consider acyclic coloring and we bound the acyclic chromatic number by a function of the maximum degree of the graph. We also study acyclic list coloring. The notion of acyclic list coloring of planar graphs was introduced by Borodin, Fon-Der Flaass, Kostochka, Raspaud, and Sopena. They conjectured that every planar graph is acyclically 5-choosable. We obtain some sufficient conditions for planar graphs to be acyclically 3-choosable.In Chapter 3, we study strong edge coloring of graphs. We prove some upper bounds of the strong chromatic index of subcubic graphs as a function of the maximum average degree. We also obtain a tight upper bound for the minimum number of colors in a strong edge coloring of outerplanar graphs as a function of the maximum degree. We also prove that the strong edge k-colouring problem, when k=4,5,6, is NP-complete for subcubic planar bipartite graphs with some girth condition. Finally, in Chapter 4, we focus on adjacent vertex-distinguishing edge coloring, or avd-coloring, of graphs. We bound the avd-chromatic number of graphs by a function of the maximum average degree. This work completes a result of Wang and Wang in 2010.