Dans cette thèse, nous étudions des problèmes d'identification des sommets dans les graphes. Identifier les sommets d'un graphe consiste à attribuer à chaque sommet un objet qui rend le sommet unique par rapport aux autres. Nous nous intéressons particulièrement aux codes identifiants : sous-ensembles de sommets d'un graphe, dominants, tels que le voisinage fermé de chaque sommet du graphe a une intersection unique avec l'ensemble. Les sommets du code identifiant peuvent être considérés comme des capteurs et chaque sommet du graphe comme un lieu possible pour une défaillance. Nous caractérisons tout d'abord l'ensemble des graphes pour lesquels tous les sommets sauf un sont nécessaires dans tout code identifiant. Le problème consistant à trouver un code identifiant optimal, c'est-'a-dire de taille minimale, étant NP-difficile, nous l'étudions sur quatre classes restreintes de graphes. Suivant les cas, nous pouvons résoudre complètement le problème (pour les graphes de Sierpinski), améliorer les bornes générales (pour les graphes d'intervalles, les graphes adjoints, la grille du roi) ou montrer que le problème reste difficile même restreint (pour les graphes adjoints). Nous considérons ensuite des variations autour des codes identifiants permettant plus de flexibilité pour les capteurs. Nous étudions par exemple des capteurs du plan capables de détecter des défaillances 'a un rayon connu avec une erreur tolérée. Nous donnons des constructions de tels codes et bornons leur taille pour des valeurs de rayons et d'erreurs fixés ou asymptotiques. Nous introduisons enfin la notion de coloration identifiante d'un graphe, permettant d'identifier les sommets d'un graphe avec les couleurs présentes dans son voisinage. Nous comparons cette coloration avec la coloration propre des graphes et donnons des bornes sur le nombre de couleurs nécessaires pour identifier un graphe, pour plusieurs classes de graphes.

La classe des graphes sans P5, c'est-à-dire des graphes ne contenant pas de chaîne induite à cinq sommets, est d'un intérêt particulier en théorie des graphes. Il s'agit en effet de la plus petite classe définie par un seul sous-graphe connexe interdit pour laquelle on ignore encore s'il existe un algorithme polynomial permettant de résoudre le problème du stable maximum. Or ce problème, dont on sait qu'il est difficile en général, est d'une grande importance en pratique (problèmes de planification, d'allocation de registres dans un processeur, biologie moléculaire...). Dans cette thèse, nous commençons par dresser un état de l'art complet des méthodes utilisées pour résoudre le problème dans des sous-classes de graphes sans P5, puis nous étudions et résolvons ce problème dans une sous-classe particulière, la classe des graphes sans P5 3-colorables. Nous apportons également des solutions aux problèmes de la reconnaissance et de la coloration de ces graphes, chaque fois en temps linéaire. Enfin, nous définissons, caractérisons et sommes capables de reconnaître les graphes "chain-probe", qui sont les graphes auxquels il est possible de rajouter des arêtes entre certains sommets de sorte qu'ils soient bipartis et sans P5. Les problèmes de ce type proviennent de la génétique et ont également des applications en intelligence artificielle.

Dans cette thèse nous étudions trois jeux à objectif compétitif sur les graphes. Les jeux à objectif compétitif proposent une approche dynamique des problèmes d'optimisation discrètes. L'idée générale consiste à associer à un problème d'optimisation (coloration, domination, etc.) un jeu combinatoire partisan de la façon suivante. Deux joueurs construisent tour à tour la structure reliée au problème d'optimisation. L'un d'eux cherche à ce que cette structure soit le plus optimale possible, tandis que l'autre essaye de l'en empêcher. Sous l'hypothèse que les deux joueurs jouent optimalement, la taille de la structure obtenue définit un invariant ludique.Nous commençons par étudier une variante 1-impropre du jeu de coloration, qui est le premier et le plus étudié des jeux à objectif compétitif. Dans ce jeu, les joueurs colorient les sommets d'un graphe de sorte que deux sommets adjacents ne partagent jamais la même couleur. Dans la version 1-impropre, un sommet peut avoir au plus un voisin ayant la même couleur que lui. Nous considérons ensuite le jeu de domination, dans lequel les deux joueurs doivent construire un ensemble dominant, c'est-à-dire un ensemble de sommets du graphe tel que tout autre sommet est adjacent à l'un des membres de cet ensemble. Finalement, nous définissons un nouveau jeu à objectif compétitif, relié au problème de coloration distinguante. Dans ce jeu, il s'agit de construire une coloration qui n'est invariante par aucun des automorphismes du graphe. Nous soulevons plusieurs interrogations stimulantes concernant ce nouveau jeu, notamment sur la caractérisation des graphes ayant un invariant ludique infini, par l'existence d'automorphismes d'ordre deux. / In this thesis, we study three competitive optimization graph games. These games allow a dynamic approach to discrete optimization problems, which is an advantageous alternative way to consider these questions. The global idea consists in defining a combinatorial partisan game, associated to the original optimization problem, like coloring, domination, etc. Two players alternatively build the structure related to the optimization problem. One of them tries to obtain a structure as optimal as possible, whereas his opponent wants to prevent him from doing it. Under the hypothesis that both players play optimally, the size of the obtained structure defines a game invariant of the graph.We start by studying a 1-improper variation of the coloring game, which is the first and the most studied competitive optimization graph game. In this game, the players colors the vertices of a graph, such that two adjacent vertices do not share the same color. In the 1-improper version, we allow a vertex to have at most one neighbor with the same color as it. Then, we study the domination game, in which the players have to build a domination set, that is a sub-set of vertices such that any other vertex is adjacent to one of the vertex in this set. Finally, we define a new game, related to the distinguishing coloring problem. This game is about building a vertex-coloring which is preserved by none of the graph automorphisms. We raise some challenging open questions about this new game, especially concerning the characterization of graphs with infinite game invariant, by the existence of order two automorphisms.

So far, nobody examined a human reaction on aposematic signals. I used red firebug's coloration and its modifications in color and pattern for testing the human reactions. People showed refusing reaction on white color and on some types of eye spots. There is a big difference between reactions on red color and black color in different human groups. This needs further research.

So far, nobody examined a human reaction on aposematic signals. I used red firebug's coloration and its modifications in color and pattern for testing the human reactions. People showed refusing reaction on white color and on some types of eye spots. There is a big difference between reactions on red color and black color in different human groups. This needs further research.

The presence of ultraviolet patterns on body, as well as perception of ultraviolet spectrum by special photoreceptors, is part of sensory ecology of many animal species, including reptiles. Most current research discusses the importance of ultraviolet signs in coloration of diurnal species. The aim of our study was to find out what character have the reflective signs in ultraviolet spectrum in overall coloration of common leopard gecko (Eubplepharis macularius) through a digital photography. The reflective pattern is present in both adults and juveniles and passes as well as the rest of the coloration by significant ontogenetic changes. Another aim was to evaluate the role of ultraviolet reflecting signs in the biology of this crepuscular-nocturnal species. We expect that the pattern contributes to their antipredatory strategies during their first few months of life, and also a white reflecting surface is preserved in adulthood, especially on their tail, which is differently coloured than the rest of the body.

Dans cette thèse, nous étudions des problèmes d'identification des sommets dans les graphes. Identifier les sommets d'un graphe consiste à attribuer à chaque sommet un objet qui rend le sommet unique par rapport aux autres. Nous nous intéressons particulièrement aux codes identifiants : sous-ensembles de sommets d'un graphe, dominants, tels que le voisinage fermé de chaque sommet du graphe a une intersection unique avec l'ensemble. Les sommets du code identifiant peuvent être considérés comme des capteurs et chaque sommet du graphe comme un lieu possible pour une défaillance. Nous caractérisons tout d'abord l'ensemble des graphes pour lesquels tous les sommets sauf un sont nécessaires dans tout code identifiant. Le problème consistant à trouver un code identifiant optimal, c'est-`a-dire de taille minimale, étant NP-difficile, nous l'étudions sur quatre classes restreintes de graphes. Suivant les cas, nous pouvons résoudre complètement le problème (pour les graphes de Sierpinski), améliorer les bornes générales (pour les graphes d'intervalles, les graphes adjoints, la grille du roi) ou montrer que le problème reste difficile même restreint (pour les graphes adjoints). Nous considérons ensuite des variations autour des codes identifiants permettant plus de flexibilité pour les capteurs. Nous étudions par exemple des capteurs du plan capables de détecter des défaillances `a un rayon connu avec une erreur tolérée. Nous donnons des constructions de tels codes et bornons leur taille pour des valeurs de rayons et d'erreurs fixés ou asymptotiques. Nous introduisons enfin la notion de coloration identifiante d'un graphe, permettant d'identifier les sommets d'un graphe avec les couleurs présentes dans son voisinage. Nous comparons cette coloration avec la coloration propre des graphes et donnons des bornes sur le nombre de couleurs nécessaires pour identifier un graphe, pour plusieurs classes de graphes. / In this thesis, we study problems on vertices identification of graphs. To identify the vertices of a graph consists in giving to each vertex of the graph an object that makes it unique. We are specially interested in the problem of identifying codes : dominating sets of vertices for which the closed neighborhood of each vertex has a unique intersection with the set. The vertices of the identifying code can be seen as sensors and each vertex of the graph as the location of a potential fault. We first classify all finite graphs for which all but one of the vertices are needed in any identifying code. Finding an optimal identifying code, i.e, an identifying code of minimum size, is a $NP$-hard problem. Therefore, we study this problem in some restricted classes of graphes. Depending on the class considered, we are able to solve this problem (for Sierpi`nski graphs), to give better bounds on the size of an identifying code than the general one (for interval graphs, line graphs and the king grid) or to prove that the problem remains NP-hard even in the restricted class (for line graphs). Then, we consider some variations of identifing codes that give flexibility to the sensors. For example, we study codes sensors able to detect faults within a radius around a fixed value. We give constructions of such codes and bounds on their size for general and asymptotic values of the radius and the tolerance on it. Finally, we introduce identifying colourings of graphs; verex-colouring of graph such that each vertex is identified by the set of colours in its closed neighbourhood. We compare this colouring of graphs with proper vertex-coloring and give bounds on the number of colours required to identify a graph, for several class of graphs.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The study was conducted at the experimental aviary of broiler chickens in the Poultry Laboratory (LAVIC) at the Federal University of Santa Maria (UFSM), Brazil. The objective of the study was to evaluate the effect of Canthaxanthin associated with 25-hydroxycholecalciferol (25-OH-D3) in the feed of broilers. The research was divided into two experiments, one with males and the other with females. In the first experiment were used in 1500 one-day-old Cobb-500TM males were distributed in a completely randomized design, totaling two treatments with fifteen replicates of 50 birds each. In the second experiment were used in 1680 one-day-old Cobb-500TM females were distributed in a completely randomized design, totaling two treatments with fifteen replicates of 56 birds each. For both experiments the treatments were: Treatment one (control diet) and Treatment two (control diet + Canthaxanthin associated with 25-OH-D3 added in diet up to 21 days of age). The experimental phase comprised a continuous period of 42 days for the experiment with males and 43 days for the experiment with females, after the birds were slaughtered for performing laboratory tests. The parameters measured were, production performance (weight gain, feed intake, feed conversion and carcass yield and cuts), physicochemical characteristics of carcass (pH, color, water-holding capacity, shear force, cooking loss, lipid oxidation of meat at different shelf times 0, 30, 60 and 90 days "post-mortem" and paw pigmentation), bone characteristics (Black Bone Syndrome, Gait Score, tibial rupture strength and percentage of calcium, phosphorus, and ashes of the tibia). For both experiments the data were submitted to analysis of variance using the statistical program SAS. For the experiment with males, significant results were found for dietary supplementation with Canthaxanthin + 25-OH-D3, where they presented better (P<0.05) body weight gain in the periods of 1-14 and of 1-21 days of age. Besides that, at 42 days of age presented higher (P<0.05) content of yellow in the breast meat, greater (P<0.05) paw pigmentation and greater (P<0.05) tibial rupture strength when supplemented with Canthaxanthin + 25-OH-D3 in the diet. For the experiment with females significant results were found for the variables of carcass coloration, where females supplemented with Canthaxanthin + 25-OH-D3 in the diet in the period of 1-21 days of age presented a higher (P<0.05) red (a*) and yellow (b*) content in the breast meat when slaughtered at 28 days of age. When they were slaughtered at 43 days of age, they presented only higher (P<0.05) breast yield in relation to the control group. It was concluded that males supplemented with Canthaxanthin + 25-OH-D3 in the diet of 1-21 days of age, presented better body weight gain in the initial production period, better breast color and paw pigmentation at 42 days of age and greater rupture force of the tibia. Females supplemented with Canthaxanthin + 25-OH-D3 in the diet of 1-21 days of age presented better breast coloration when slaughtered at 28 days of age, and when slaughtered at 43 days of age presented only higher breast yield. / O estudo foi realizado no aviário experimental de frangos de corte do Laboratório de Avicultura (LAVIC) da Universidade Federal de Santa Maria (UFSM), Brasil. O objetivo principal do estudo foi avaliar o efeito da Cantaxantina associada ao 25-hidroxicolecalciferol (25-OH-D3) na alimentação de frangos de corte. A pesquisa foi dividida em dois experimentos sendo, Experimento I com machos e Experimento II com fêmeas. No Experimento I foram utilizados 1500 machos Cobb-500® de um dia de idade, distribuídos em um delineamento inteiramente casualisado (DIC), totalizando dois tratamentos com quinze repetições de 50 aves cada. No segundo experimento foram utilizadas 1680 fêmeas Cobb-500® de um dia de idade, distribuídas em um delineamento inteiramente casualisado (DIC), totalizando dois tratamentos com quinze repetições de 56 aves cada. Para ambos experimentos os tratamentos foram: Tratamento 1 (dieta controle) e Tratamento 2 (dieta controle + Cantaxantina associada a 25-OH-D3 adicionado na dieta até 21 dias de idade). A fase experimental compreendeu um período continuo de 42 dias para o experimento com machos e de 43 dias para o experimento com fêmeas, após foi realizado o abate das aves, para realização das análises laboratoriais. Os parâmetros mensurados, foram, desempenho zootécnico (ganho de peso, consumo de ração, conversão alimentar e rendimento de carcaça e cortes), características físico-químicas da carcaça (pH, coloração, capacidade de retenção de água, força de cisalhamento, perda por cocção, oxidação lipídica da carne nos diferentes tempos de prateleira 0, 30, 60 e 90 dias “post-mortem” e pigmentação da pata), características ósseas (Black Bone Syndrome, Gait Score, força de ruptura da tíbia e percentual de cálcio, fósforo e cinzas da tíbia). Para ambos os experimentos os dados foram submetidos à análise de variância, através do programa estatístico SAS. Para o experimento com machos foram encontrados resultados significativos para a suplementação com Cantaxantina + 25-OH-D3 na dieta, onde estes apresentaram maior (P<0,05) ganho de peso corporal nos períodos de 1-14 e de 1-21 dias de idade. Além disso, aos 42 dias de idade apresentaram maior (P<0,05) teor de amarelo (b*) na carne de peito, maior (P<0,05) pigmentação da pata e maior (P<0,05) força de ruptura da tíbia quando suplementados com Cantaxantina + 25-OH-D3 na dieta. Já para o experimento com fêmeas foram encontrados resultados significativos, para as variáveis de coloração da carcaça, onde fêmeas suplementadas com Cantaxantina + 25-OH-D3 na dieta no período de 1-21 dias de idade, apresentaram maior (P<0,05) teor de vermelho (a*) e amarelo (b*) na carne de peito quando abatidas aos 28 dias de idade. Quando abatidas aos 43 dias de idade apresentaram somente maior (P<0,05) rendimento de peito em relação ao grupo controle. Concluiu-se que machos de corte suplementados com Cantaxantina + 25-OH-D3 na dieta de 1-21 dias de idade, apresentaram melhor ganho de peso corporal no período inicial de produção, melhor coloração de peito e pata aos 42 dias de idade e maior força de ruptura da tíbia. Já fêmeas de corte suplementadas com Cantaxantina + 25-OH-D3 na dieta de 1-21 dias de idade, apresentaram melhor coloração de peito quando abatidas aos 28 dias de idade, e quando abatidas aos 43 dias de idade, apresentaram somente maior rendimento de peito.

Philosophiae Doctor - PhD / In this work we primarily set out to investigate the technique of Aqueous Chemical Growth as a means of producing WO3 thin films that find applications in gas sensing and electrochromism. For the first time we demonstrated in this work, the heterogenous nucleation and growth of WO3 thin films on plain glass substrates and F-doped SnO2-glass substrates. This was achieved without the use of surfactants and template directing methods, using as a precursor solution Peroxotungstic Acid generated from the action of 30% H2O2 on pure W powder. The substrates used needed no surface-modification. On the plain glass substrates (soda lime silicates) a variety of micronanostructures could be observed prime of which were nanoplatelets that acted as a basic building block for the self-assembly of more hierarchical 3-d microspheres and thin films. On FTO a wide variety of micro-/nanostructures were observed dominant amongst which were urchin-like microspheres. The dominant crystallographic structure observed (through X-ray diffraction analysis, SAED, HRTEM) for the WO3 thin films on both substrate types post-annealing at 500 ˚C for a period of 1 - 2 h, was hexagonal-WO3. Next was monoclinic WO3. On rarer occasions the formation of triclinic and cubic WO3 was observed. The thin films produced showed a fairly high degree of porosity and had thicknesses in the range of 900 nm - 3.5 μm. I-V characterisation measurements using a 4-point collinear probe Keithley source alongside photoluminescence was used to establish the insulating nature of some of the films as well as their sub-stoichiometric nature. X-ray Photoelectron Spectroscopy was used to confirm the substoichiometric nature of some of the films.

Nos estudos sobre a teoria da Seleção Sexual, as libélulas têm sido amplamente estudadas devido à grande variedade de padrões comportamentais, de coloração e táticas reprodutivas. Como forma de demonstrar táticas reprodutivas adotadas por duas espécies de libélulas, esta dissertação teve como objetivos principais: i) investigar o papel de traços secundários como a coloração corporal na competição intra-sexual de uma espécie territorial e ii) analisar se os traços corporais como tamanho e morfologia das asas predizem a tática de acasalamento adotada por machos de uma espécie nãoterritorial. Sugere-se que a coloração corporal pode predizer o resultado de lutas e também se correlacionar positivamente com a condição física dos machos territoriais de Tigriagrion aurantinigrum. Ademais, traços corporais como o tamanho e a morfologia das asas influenciam na tática reprodutiva utilizada por machos não-territoriais de Epipleoneura williamsoni. Portanto, com os resultados obtidos, conclui-se que a variação nos sinais visuais exerce um papel essencial na comunicação animal e na resolução de conflitos, indicando ainda que pode haver uma sinalização da condição física dos machos. Além disso, os resultados mostraram evidências em como diferentes táticas reprodutivas se relacionam com traços corporais como agilidade e tamanho corporal, os quais podem influenciar no sucesso reprodutivo dos indivíduos. / In studies concerning Sexual Selection theory, dragonflies and damselflies have been well studied due to their wide range of behavioral, color and reproductive tactics patterns. To demonstrate reproductive tactics adopted by two damselfly species, this study aimed to: i) investigate the role of secondary traits such as body coloration in intrasexual competition of a territorial species and ii) analyze if body traits such as size and wing morphology predicts the adopted tactic by non-territorial males. It is suggested that body coloration can predict the fight outcome and also positively correlates with males physical condition in territorial males of Tigriagrion aurantinigrum and body traits such as body size and wing morphology influence the reproductive tactic adopted by non-territorial males of Epipleoneura williamsoni. Therefore, with these results, it is concluded that the visual signalling variation plays an important role on the animal comunication and conflict resolution, which also may indicate that there is a signalling on the males physical condition. Furthermore, the results showed evidence in how different reproductive tactics are related to body traits such as agility and size, which can influence on individuals reproductive success.