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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1041

Caractérisation pharmacologique et moléculaire des dyskinésies tardives chez un modèle de primate non humain

Mahmoudi, Souha 08 1900 (has links)
Les dyskinésies tardives (DT) sont des troubles moteurs associés à l’utilisation chronique des antagonistes des récepteurs dopaminergiques D2 tels que les antipsychotiques et le métoclopramide. Ces dyskinésies correspondent à une incoordination motrice portant préférentiellement sur la musculature oro-faciale. La gestion des DT s'est imposée comme défi de santé publique surtout en l’absence d’une alternative thérapeutique efficace et abordable. L’hypothèse classiquement avancée pour expliquer la physiopathologie des DT inhérente au traitement par les antipsychotiques s’articule autour de l’hypersensibilité des récepteurs dopaminergiques D2, cibles principales de ces molécules. Néanmoins, plusieurs données remettent la véracité de cette hypothèse en question. Hypothèse: nous proposons que le blocage chronique des récepteurs dopaminergiques soit effectivement responsable d’un phénomène d’hypersensibilisation mais contrairement à l’hypothèse classique, cette hypersensibilisation porterait sur des paramètres de la transmission dopaminergique autres que les récepteurs D2. De même nous postulons que cette hypersensibilisation se traduirait par des altérations des cascades signalétiques au niveau des cellules du striatum. Ces altérations aboutissent à des changements portant sur le récepteur nucléaire (Nur77), qui est hautement associé au système dopaminergique; l’induction de ces récepteurs déclencherait des cascades associées à la compensation ou à la genèse des DT. Matériels et méthodes: 23 femelles Cebus apella, réparties en 3 groupes: groupe halopéridol, groupe clozapine, et groupe contrôle, ont été exposées aux traitements respectifs pendant 6-36 mois. Après l’analyse comportementale, les animaux ont été décapités et leurs cerveaux isolés pour fin d’analyse. Hybridation in situ: nous avons fait appel à cette technique pour mesurer l’expression de l’ARNm de Nur77 et du neuropeptide enképhaline. Hybridation in situ double: nous avons exploités cette technique pour identifier les populations neuronales exprimant les récepteurs dopaminergiques D3 et localiser leur éventuelle induction. Autoradiographies des récepteurs dopaminergiques D1, D2 et D3 et autoradiographies des récepteurs i glutamatergiques mGluR5. Ces autoradiographies avaient pour objectif d’évaluer l’expression de ces différents récepteurs. Mutagenèse dirigée et transfection cellulaire: nous faisons appel à ces techniques pour reproduire le polymorphisme identifié au niveau de la région 3’UTR de l’ARNm Nur77 et évaluer l’impact que pourrait avoir ce polymorphisme sur la stabilité de l’ARNm Nur77 sinon sur l’expression de la protèine Nur77. Western Blot des kinases ERK 1 et 2: cette technique nous a servi comme moyen pour quantifier l’expression globale de ces kinases. Analyses statistiques: l’expression de l’ARNm Nur77 a été évaluée en utilisant l’analyse de la variance à un seul facteur (One way ANOVA). Nous avons procédé de la même façon pour mesurer l’expression des récepteurs D2, D3 et mGluR5. Résultats: le groupe des animaux traités par l’halopéridol montre une plus forte expression des récepteurs D3 par rapport aux sujets des autres groupes. Cette expression se produit au niveau des neurones de la voie directe. De plus, cette augmentation corrèle positivement avec la sévérité des DT. L’expression des récepteurs D2 et mGluR5 reste relativement inchangée entre les différents groupes, alors qu’un gradient d’expression a été observé pour le récepteur D1. Par ailleurs, Nur77 est induit par l’halopéridol, alors que son expression semble baisser chez les animaux traités par la clozapine. L’induction de l’expression de Nur77 par l’halopéridol est plus accrue chez les animaux non dyskinétiques. Les animaux traités par la clozapine démontrent une expression amoindrie de l’ARNm de Nur77 qui tend à être plus faible que l’expression de base. D’autre part, la présence du polymorphisme au niveau de la région 3’UTR semble affecter l’expression cellulaire de Nur77. Conclusion: ces résultats confortent notre hypothèse concernant l’existence d’un phénomène d’hypersensibilisation prenant place suite un traitement chronique par les antipsychotiques. Ce phénomène s’est traduit par une augmentation de l’expression des récepteurs D3 sans porter sur les récepteurs D2 tel que prôné classiquement. Cette hypersensibilisation des récepteurs D3 implique également l’existence d’un débalancement des voies striatales pouvant ainsi sous tendre l’apparition des DT. Ces résultats dévoilent ainsi un nouveau mécanisme qui pourrait contribuer à l’apparition des DT et pourraient permettre une meilleure gestion, nous l’espérons, des DT à l’échelle clinique. / Tardive dyskinesia (TD) is a potentially disabling and irreversible motor complication including all persistent, abnormal, involuntary movements, classicaly caused by the chronic therapy with typical antipsychotic drugs (haloperidol, fluphenazine). Atypical antipsychotic drugs like clozapine have been introduced because they showed little potential to induce TD, raising the hope to completely eradicate this complication. However, it has been later shown that these drugs have several serious metabolic side- effects and that some atypical molecules are as responsible as typical drugs for inducing TD. Besides, the typical drugs are still widely prescribed in a large spectrum of disorders. For all these reasons, TD still constitutes a major challenge for psychotic disorders treatments especially that the pathophysiology of TD remains elusive and therapeutics are difficult. Based on rodent experiments, it was proposed that dopamine D2 receptor hypersensitivity could be responsible for TD. However, this hypothesis lacks strong support in humans. We suggest, in this thesis, that TD is associated with the hypersensitivity of other receptors, than D2. To investigate the neurochemical basis of TD, we chronically exposed 23 adult capuchin monkeys to haloperidol (median 18.5 months, N=11) or clozapine (median 6 months, N=6). Six unmedicated animals were used as controls. Five haloperidol-treated animals developed mild TD movements, and no TD was observed in the clozapine group. Using receptor autoradiography, we measured dopamine D1, D2, D3 and mGluR5 receptor levels. We also examined the D3 receptor/preprotachykinin mRNA co-expression, and quantified enkephalin and Nur77 mRNA levels, in striatal sections. Unlike clozapine, haloperidol strongly induced dopamine D3 receptor binding sites in the anterior striatum, particularly in TD animals, and binding levels positively correlated with TD intensity. In contrast, D2 receptor binding was comparable to controls, and dopamine D1 receptor binding reduced in the anterior (haloperidol and clozapine) and posterior (clozapine) putamen. Preprotachykinin mRNA-labeled cell count was unaffected by either haloperidol or clozapine, enkephalin mRNA widely increased in all animals, but to a greater extent in TD-free animals. Nur77 mRNA levels in the caudate-putamen were strongly up regulated iv in animals exposed to haloperidol but were spared following clozapine treatment. Interestingly, within the haloperidol-treated group, TD-free animals showed higher Nur77 expression in putamen sub territories compared with dyskinetic animals. These results corroborate our hypersensitivity hypothesis, and indicate that an imbalance between the striatal pathways could contribute to the pathophysiology of TD.
1042

Investigation of the biology and cross-breeding of populations of Pareuchaetes insulata (Lepidoptera : Arctiidae) and the implications for the biological control of Chromolaena odorata (Asteraceae) in South Africa.

Dube, Nontembeko. 27 May 2014 (has links)
Larvae of Pareuchaetes insulata were released in South Africa for the biological control of the invasive weed Chromolaena odorata. Pareuchaetes insulata has proved to be a difficult agent to establish in the field in South Africa, for various possible reasons. Populations collected from Florida and Jamaica (their aboriginal home) were released separately at several sites each in South Africa, but only one population (Florida) was definitely established. It is possible that adults from this established population interbred with adults from the Jamaican population released at nearby sites. The aims of this study were to determine whether there were any differences in biology between the two populations and whether hybridization affected the fitness of either. Trials involved: (i) pure-breeding of both Florida (F) and Jamaica (J) populations; (ii) cross-breeding of the two populations and; (iii) back-crossing of the hybrids with the parent populations. The fitness of these populations was determined by measuring adult longevity and fecundity, egg viability, and larval development and survival rates. The F population was superior to the J population in most of parameters measured, including fecundity. Hybridization of these populations reduced the fitness of the F population. It is unknown whether these differences in fitness reflect differences in their native regions, laboratory cultures or response to South African C. odorata. It appears that different populations of P. insulata have different levels of fitness, and that hybridization negatively affects the fitness of stronger populations. The lower fitness of the J population may have reduced its likelihood of establishing successfully, and even reduced the fitness of the established F population where the populations came into contact. These results caution that the possible consequences of mixing different genotypes of a biocontrol agent species should be properly investigated prior to their release in the same country. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.
1043

Phylogenetic Analysis of Subtribe Alopecurinae (Poaceae)

Boudko, Ekaterina 12 March 2014 (has links)
Subtribe Alopecurinae (Poeae, Poaceae) sensu lato‘s seven genera share interesting morphological similarities (dense spicate panicles and one-flowered spikelets) that were widely thought to have a common origin. However, recent molecular evidence for three of the genera has suggested that the subtribe may be polyphyletic. To test this, five DNA regions were sequenced and analyzed using phylogenetic methods. Results confirm that Alopecurinae s.l. as presently treated is polyphyletic and should be dissolved. Additionally, the genus Cornucopiae may be just another Alopecurus. Limnas and Pseudophleum are not closely allied to Alopecurus or each other, and are even further from Phleum. Phleum is a distinct lineage that is not closely allied to any other included Alopecurinae genus. Evidence for revising infrageneric classifications of Alopecurus and Phleum is presented, as is evidence for separating A. magellanicus into two or more subspecies.
1044

Elektrochemisch gestützte Immobilisierung bioaktiver Moleküle an Titanoberflächen / Electrochemically Assisted Immobilization of Bioactive Molecules on Titanium Surfaces

Beutner, René 16 February 2012 (has links) (PDF)
Ein Schlüsselfeld der gegenwärtigen Biomaterialforschung ist die Modifizierung von Oberflächen mit Bestandteilen der extrazellulären Matrix (EZM) oder Molekülen, die bestimmte Funktionen nachahmen. Trotz einer Reihe positiver Ergebnisse in vitro und in vivo ist es mit den gegenwärtig zur Verfügung stehenden Immobilisierungsmethoden nicht möglich, unterschiedliche Komponenten in einem Prozessschritt zu immobilisieren, definierte Freisetzungscharakteristika für gleiche und/oder unterschiedliche Moleküle zu realisieren und die Beschichtung der Oberflächen nach Sterilisation der Implantate vorzunehmen, um empfindliche bioaktive Substanzen, wie Proteine, vor Schädigung zu bewahren. An diesem Punkt setzt die vorliegende Arbeit mit dem Ziel an, ein nukleinsäurebasiertes Immobilisierungssystem für Titanwerkstoffe zu entwickeln. Es wird zunächst am Beispiel eines Peptids mit der Aminosäuresequenz Arginin–Glyzin–Asparaginsäure (RGD) nachgewiesen, dass an der Grenzfläche Passivschicht/Elektrolyt von Titanwerkstoffen vorliegende Moleküle in durch anodische Polarisation verdickte Oxidschichten partiell eingebaut werden können und dabei ihre Funktionalität erhalten bleibt. Diese Immobilisierungsmethode wird zum Immobilisierungssystem erweitert, indem Nukleinsäureeinzelstränge mit der beschriebenen Methode als Ankerstränge (AS) in anodisch formierte Oxidschichten fixiert und in einem zweiten Prozessschritt mit komplementären Gegensträngen (GS) hybridisiert werden. In der Arbeit wird gezeigt, dass das Peptid in einem weiten Parameterbereich der elektrochemischen Bedingungen immobilisiert werden kann. Demgegenüber führen im Falle des nukleinsäurebasierten Immobilisierungssystems die Bildung reaktiver Sauerstoffspezies, die Photoaktivität der Oxidschicht sowie mehrfache Trocknungen und Wiederbenetzungen zu einer Schädigung gebundener AS bis hin zu einem vollständigen Verlust der Hybridisierbarkeit. Durch Zugabe von Ethanol in hoher Konzentration während des Immobilisierungsschritts, Arbeit unter Lichtausschluss sowie Vermeidung mehrerer Trocknungen und Wiederbenetzungen können die Nebenwirkungen soweit eingeschränkt werden, dass alle immobilisierten AS hybridisierbar sind. Nach dessen Etablierung im Rahmen dieser Arbeit ist es in nachfolgenden Projekten möglich, das nukleinsäurebasierte Immboilisierungssystem zu einem modularen, nukleinsäurebasierten Immobilisierungssystem zu erweitern, um die eingangs beschriebenen Grenzen etablierter Methoden zu umgehen. Dazu müssen im zweiten Prozessschritt Konjugate aus GS und bioaktiven Molekülen, wie z. B. Peptide oder Wachstumsfaktoren, eingesetzt werden. Weiterhin können durch die Nutzung verschiedener Längen und Basensequenzen die Hybridstabilität und damit die Freisetzungskinetik beeinflusst werden. / Surface functionalization with bioactive molecules is a main field in current biomaterial research. However, in vitro and in vivo results are heterogeneous. This may be at least partially attributed to the limits of the applied immobilization methods. With established immobilization methods possibilities are limited to immobilize different molecules in one step, to implement defined release kinetics for similar and/or different substances, or to carry out the immobilization after sterilization of the implant to save sensitive molecules from damage. Therefore in this thesis a nucleic acid based immobilization system for bioactive molecules is developed for titanium based materials. Using a peptide with the amino acid sequence arginine–glycine–aspartic acid (RGD) it is demonstrated at first, that small molecules, being present at the interface electrolyte/passive layer, can be immobilized by their partial incorporation in anodically formed oxide layers. The immobilization can be carried out in a wide range of electrochemical parameters and the peptide preserves its biological function under all conditions. This immobilization method is enhanced by utilizing single-stranded nucleic acids as anchor strands (AS), which can be hybridized by complementary strands (CS) in a second step. Contrary to the peptide, bound AS are damaged by the formation of reactive oxygen species during anodic polarization of the substrate, the photoyctivity of the titanium oxide layer and multiple drying and wetting cycles. These side effects must be constrained by adding ethanol in a high concentration to the electrolyte during the immobilization procedure, excluding light during preparation and avoiding multiple drying and wetting cycles. Applying these conutermeasures, a 100% hybridization of immobilized AS can be achieved. After establishing the nucleic acid based immobilization system it can be developed further to a modular, nucleic acid based immobilization system to overcome limitations of established immobilization methods. At first, conjugates of CS and bioactive molecules, such as peptides or growth factors, should be used in the hybridization step for a true functionalization of the surface. Furthermore, hybrid stability and thus release kinetics can be adjusted by using CS of different length and base sequences.
1045

Expressão diferencial de genes induzidos por antracnose em feijoeiro em resposta à indução da resistência por silício / Differential expression of genes activated by anthracnose in response to silicon induced resistance

Ana Luiza Ahern Beraldo 08 August 2012 (has links)
O feijão é importante fonte carboidratos, vitaminas, minerais e fibras. No Brasil, a produtividade desta leguminosa é baixa e um dos fatores é a ocorrência de doenças como a antracnose causada pelo Colletothrichum lindemuthianum, que gera perdas de até 100% da produção. Plantas possuem diversos mecanismos de defesa contra patógenos e relatos apontam que o silício é capaz não só de promover mudanças morfológicas nas folhas, mas também de ativar os genes de resistência. O presente trabalho foi dividido em três estudos que tinham como objetivo: (1) entender a resposta de três cultivares de feijoeiro ao silício disponível na solução nutritiva; (2) identificar a contribuição do Si na expressão de genes relacionados à infecção pelo fungo através da construção de duas bibliotecas subtrativas por supressão (SSH), visando selecionar genes diferencialmente representados durante a infecção da planta com a raça 65 de C. lindemuthianum (a) e durante a infeção da planta na presença de uma maior dose silicato de potássio (75 ppm) no substrato (b); (3) identificar a resposta de dez transcritos selecionados no Estudo 2 para tentar entender a resposta dos mesmos em diferentes períodos (0; 6; 42; 72 h) após a inoculação, com ou sem suplemento de Si. Como resultados, foi observado que para as três cultivares avaliadas o Si começa a ser absorvido 14 dias após o transplante. Também foi identificado por de microscopia de varredura (MEV) que não há diferença significativa entre o número de tricomas e cada cultivar, mas que para o número de estômatos a cultivar IAC-Harmonia destacou-se das demais. Além disso, quando as três cultivares foram suplementadas com Si, houve a formação de uma cera epicuticular descrita como mecanismo de defesa da planta contra fungos; e que através de EDX (Energy-dispersive X-ray spectroscopy) foi possível constatar que plantas tratadas com Si apresentam maior teor deste elemento nas folhas. Através de inoculações com a raça 65 do patógeno verificou-se o efeito do mineral na redução da severidade da doença nas cultivares IAC-Harmonia e Pérola. No segundo estudo, duas bibliotecas de hibridização subtrativa por supressão (SSH), foram construídas visando selecionar os genes diferencialmente expressos entre plantas inoculadas e não-inoculadas (A) e entre plantas inoculadas e tratadas ou não com 75 ppm de Si (B). Foram geradas 991 sequências únicas, anotadas através do GeneOntolgy. Quinze genes de cada biblioteca foram selecionados para os experimentos de validação por RT-qPCR. Para a Biblioteca A, 11/15 genes foram positivamente regulados, e em B, 14/15. No terceiro estudo ficou evidenciado que a inoculação com o patógeno alterou positivamente a expressão de sete genes, enquanto que o tratamento com 75 ppm de Si alterou a expressão de oito genes, em pelo menos um dos tempos avaliados / Beans are an important source of carbohydrates, vitamins, minerals and fibers. In Brazil, this legume still has low productivity and one of the factors involved is the occurrence of diseases such as anthracnose, caused by the fungus Colletothrichum lindemuthianum, which causes losses in production of up to 100%. Plants present several defense mechanisms against pathogens and the reports indicate that silicon does not only promote morphological changes in leaves, but also activates resistance genes. This work was divided into three studies aiming: (1) to understand the response of three bean cultivars to a silicon source in a nutrient solution, (2) to identify the contribution of Si in the expression of genes related to the infection by the fungus by constructing two subtractive suppression libraries (SSH), to select genes differentially represented during infection of the plant with race 65 of C. lindemuthianum (a) and during infection of the plant in the presence of higher dose of potassium silicate (75 ppm) in the substrate (b), (3) to identify the response of ten selected transcripts in Study 2 in various periods (0, 6, 42, 72 h) after inoculation, with or without supplemental Si. As a result, it was observed that for all three cultivars Si begins to be absorbed 14 days after transplantation. Was also identified by microscopy (SEM) that there is no significant difference between the number of trichomes among cultivars, but that the number of stomata for the IAC-Harmonia stood out from the rest. Moreover, when the three cultivars were supplemented with Si, thus forming an epicuticular wax described as a defense mechanism against plant fungi, and that by EDX (Energy-dispersive X-ray spectroscopy) it was found that plants treated with Si have higher content of this element in leaves. Through inoculations with race 65 of the pathogen it was verified the effect of the mineral in reducing disease severity in IAC-Pérola and IAC - Harmonia. In the second study, two libraries from suppression subtractive hybridization (SSH) were constructed in order to select the differentially expressed genes between inoculated and non-inoculated (A) and between plants inoculated and treated or not with 75 ppm of Si (B). In total, 991 unique sequences were generated, those recorded by GeneOntolgy. Fifteen genes from each library were selected for the validation experiments by RT-qPCR. For library A, 11/15 genes were positively regulated, and in B, 14/15. In the third study it is showed that inoculation with the pathogen positively altered expression of seven genes, whereas treatment with 75 ppm of Si changed the expression of eight genes, in at least one of the times analyzed
1046

Invasion, démographie et évolution : le cas de l'hybridation / Invasion, demography and evolution : the case of hybridization

Bermond, Gérald 16 December 2013 (has links)
Cette thèse s’inscrit dans le contexte de la biologie de l’invasion de la chrysomèle des racines du maïs, Diabrotica virgifera virgifera (Dvv), en Europe. Les introductions multiples de cette peste sur le vieux continent à partir des années 1990 et en provenance des États-Unis ont conduit à la formation de plusieurs foyers envahissants dont deux principaux, différenciés génétiquement et situés en Italie du Nord-Ouest (Italie NO) et en Europe Centrale et du Sud-Est (Europe CSE). Ces deux foyers sont entrés en contact en 2008, en Italie du Nord, dans la région de la Vénétie. L’objectif principal de ces trois années de recherche était de détecter, d’étudier et de documenter un cas précis d’hybridation au cours d’une invasion biologique. Dans un premier temps, j'ai montré que la zone de contact détectée en Vénétie résultait bien en une zone hybride. Pour cela plusieurs types d’analyses de génétique des populations ont été réalisés à l’aide de marqueurs micro-satellites. Dans un second temps, j'ai exploité cette zone hybride et utilisé la théorie des clines neutres et le déséquilibre de liaison pour estimer la dispersion (σ) de Dvv en Italie du Nord aux alentours de 20 km.génération−1/2. Enfin j'ai montré l’absence d'impact de l’hybridation au cours de l’invasion européenne de Dvv in natura, en mesurant sur des génotypes hybrides et parentaux, de nombreux traits phénotypiques positivement liés à la fitness des individus. Ainsi, une sélection ou contre sélection des hybrides est à exclure dans ce cas précis d’hybridation et la dynamique de l’invasion de cette peste en Europe ne devrait être affectée en aucune façon. / This thesis deals with the invasion biology of the western corn rootworm, (WCR) in Europe. Multiple introductions of this pest in Europe from the United States and the 90’s, led to the formation of two main invasive outbreaks, genetically differentiated and located in Northwest Italy (NW Italy) and in Central and South-Eastern Europe (CSE Europe). Both outbreaks converged towards each other and came into contact in 2008, in the region of Veneto (Northern Italy). The main objective of these three years of research was to detect study and document a precise case of hybridization during a biological invasion. First of all, I showed that the contact zone detected in Veneto results in a hybrid zone. For that, several types of population genetics analyses were performed using microsatellite markers. In a second time, I exploited this hybrid zone and used the theory of neutral clines and the linkage disequilibrium to estimate dispersal (σ) of WCR in Northern Italy around 20 km.generation-1/2. Finally I showed the absence of impact of hybridization in the european invasion of WCR in natura, by measuring on hybrid and parental genotypes, numerous phenotypic traits positively associated to the fitness of individuals. Thus, a selection or a selection against hybrids is excluded in this particular case of hybridization and the invasion dynamics of WCR in Europe should not be affected in any way.
1047

Contribution à la conception des filtres bidimensionnels non récursifs en utilisant les techniques de l’intelligence artificielle : application au traitement d’images / Contribution to the design of two-dimensional non-recursive filters using artificial intelligence techniques : application to image processing

Boudjelaba, Kamal 11 June 2014 (has links)
La conception des filtres a réponse impulsionnelle finie (RIF) peut être formulée comme un problème d'optimisation non linéaire réputé pour être difficile sa résolution par les approches conventionnelles. Afin d'optimiser la conception des filtres RIF, nous explorons plusieurs méthodes stochastiques capables de traiter de grands espaces. Nous proposons un nouvel algorithme génétique dans lequel certains concepts innovants sont introduits pour améliorer la convergence et rendre son utilisation plus facile pour les praticiens. Le point clé de notre approche découle de la capacité de l'algorithme génétique (AG) pour adapter les opérateurs génétiques au cours de la vie génétique tout en restant simple et facile à mettre en oeuvre. Ensuite, l’optimisation par essaim de particules (PSO) est proposée pour la conception de filtres RIF. Finalement, un algorithme génétique hybride (HGA) est proposé pour la conception de filtres numériques. L'algorithme est composé d'un processus génétique pur et d’une approche locale dédiée. Notre contribution vise à relever le défi actuel de démocratisation de l'utilisation des AG’s pour les problèmes d’optimisation. Les expériences réalisées avec différents types de filtres mettent en évidence la contribution récurrente de l'hybridation dans l'amélioration des performances et montrent également les avantages de notre proposition par rapport à d'autres approches classiques de conception de filtres et d’autres AG’s de référence dans ce domaine d'application. / The design of finite impulse response (FIR) filters can be formulated as a non-linear optimization problem reputed to be difficult for conventional approaches. In order to optimize the design of FIR filters, we explore several stochastic methodologies capable of handling large spaces. We propose a new genetic algorithm in which some innovative concepts are introduced to improve the convergence and make its use easier for practitioners. The key point of our approach stems from the capacity of the genetic algorithm (GA) to adapt the genetic operators during the genetic life while remaining simple and easy to implement. Then, the Particle Swarm Optimization (PSO) is proposed for FIR filter design. Finally, a hybrid genetic algorithm (HGA) is proposed for the design of digital filters. The algorithm is composed of a pure genetic process and a dedicated local approach. Our contribution seeks to address the current challenge of democratizing the use of GAs for real optimization problems. Experiments performed with various types of filters highlight the recurrent contribution of hybridization in improving performance. The experiments also reveal the advantages of our proposal compared to more conventional filter design approaches and some reference GAs in this field of application.
1048

Le design critique et les nouveaux enjeux de conception : un territoire historico-géopolitique de 1960 à nos jours / Critical design and new challenges of conception : a historico-geopolitical domain from 1960 up to the present day

Bertrand, Gwenaëlle 07 November 2016 (has links)
Ce travail de recherche contribue au questionnement sur les nouveaux enjeux de conception soulevés par le design critique. À plusieurs égards, le corpus de cette thèse repose sur une histoire de la contre-histoire. Une manière de faire et de penser dont l’historicité la plus évidente se situe à la fin des années 1960, lorsque certains designers ont souhaité porter le projet vers la mise en œuvre d’un écart afin d’interroger la société par les moyens du design. Une attitude qui instaure la conception à l’instar d’une logique de la désadaptation des habitudes et des manières conventionnelles de penser. La notion de critique, du grec krinein, qui signifie «séparer», «distinguer», prend ici tout son sens en instaurant, non pas une rupture, mais un déplacement, qui aménage des entre-deux et ménage des porosités de la pensée et de la conception. De l’individu augmenté à l’individu modifié, cette thèse révèle de surcroît, l’inquiétude d’une mainmise au delà de l’invention de l’artificiel et aux abords du biologique. Au gré d’un épuisement de la question du critique en design, nous décelons des moyens de déconstruire les systèmes de la discipline et ses réinventions. / This research work aims to contribute to the study of the new challenges of conception raised by critical design. In several respects the corpus of this thesis is based on a history of coun¬ter history, a way of doing and thinking whose conspicuous historicity takes place in the late sixties when a few designers decided to reconsider the notion of project and stray from the straight and narrow in order to question society through the means of design. The notion of criticism - from the Greek krinein meaning «separate», «discriminate» - takes on its full meaning by introducing a shift (not a break) which makes room for inter¬vals and allows sensitive thinking and conception. From human enhancement to human modification, this thesis also reveals a number of concerns which go beyond the invention of artificial means and touch upon biological aspects. Considering that the critical dimen¬sion in the field of design has been exhausted, this research highlights a few ways to deconstruct the operating principles of this discipline as well as its reinventions.
1049

Analýza karyotypu vakonošů (Psychidae, Lepidoptera) metodami klasické a molekulární cytogenetiky

FLEGROVÁ, Martina January 2017 (has links)
Due to their phylogenetic position, Psychidae play an important role in the investigation of the W chromosome origin in Lepidoptera. Several species of Psychidae were tested for the presence of sex-chromatin and investigated via comparative genomic hybridization. Furthermore, odd chromosome numbers and a Z univalent were observed in females. Overall, this study brings tangible evidence for the absence of the W chromosome in Psychidae, thus contributes to complex knowledge of the W chromosome evolution. In addition, karyotypes of the given species were analyzed using 18S rDNA and histone H3 probes. The results indicate relative stability of their karyotypes.
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Hibridação, performance e utopia nas canções de rap / Hybridization, performance and utopia in rap songs

Cortez, Marcia Felix da Silva 23 April 2010 (has links)
The present work has as object of investigation the understanding of rap songs as voco-hybrid musical expressions in the Northeast, bring the dialogue between the African-American oral sources and the Northeast. The result of this meeting is built by the analyses of the eighteen songs from Northeastern, and included groups from the design of the poet zumthoriana voice. The identity mapping of MC/a listener of rap has made it possible to deepen looks that were conducted by hybridization, performance considerations, and utopia and, in turn, subsidized a broad approach on textual complexity of rap songs. / Fundação de Amparo a Pesquisa do Estado de Alagoas / O presente trabalho tem por objeto de investigação a compreensão das canções de rap como expressões voco-musicais híbridas que, no nordeste, trazem o diálogo entre as fontes orais afro-americanas e a cantoria nordestina. O resultado deste encontro é construído pelas análises das dezoito canções, oriundas de grupos nordestinos, e compreendidas a partir da concepção de poeta da voz zumthoriana. O mapeamento identitário do/a MC e do/a ouvinte de rap tornou possível aprofundar olhares que foram conduzidos pelas considerações sobre hibridação, performance e utopia e, por sua vez, subsidiaram uma abordagem ampla sobre a complexidade textual das canções de rap.

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