Les abeilles en libre vol montrent des capacités cognitives visuelles remarquables mais les bases neurales sous-jacentes ne peuvent pas être étudiées chez des insectes en vol. À l'inverse, le cerveau des abeilles immobilisées est accessible mais ne permet pas d'explorer l'apprentissage visuel. Pour dépasser cette limite, notre objectif a été d'établir un dispositif de réalité virtuelle pour pouvoir tester l'apprentissage visuel sur des abeilles attachées. Dans un premier temps, les abeilles ont été testées sur leur capacité à discriminer des couleurs en s'appuyant sur les renforcements positifs ou négatifs qui leur étaient associés. Ces expériences ont permis de mettre en évidence le rôle de la vision active dans la réalité virtuelle et l'importance de la phototaxie dans ce type de système. Grâce à ce dispositif, un apprentissage non élémentaire en réalité virtuelle, le patterning négatif, a été mis en place. Ainsi il a été montré que les abeilles étaient capables de résoudre cette tache en réalité virtuelle malgré sa complexité. Enfin, en s'appuyant sur le protocole de discrimination de couleurs, l'activation du cerveau a été étudiée au cours d'un test de mémoire des couleurs en analysant l'expression de gènes considérés comme des marqueurs de l'activité neurale. Les résultats de cette thèse, fournissant deux protocoles de réalité virtuelle solides pour étudier les apprentissages visuels élémentaires et non élémentaires, constituent une avancée considérable vers la possibilité de comprendre les bases neurales sous-jacentes à ces apprentissages chez l'abeille qu'ils soient simples ou complexes. / Free flying bees are known for their impressive visual cognition abilities, but the neural bases underlying those are poorly studied because of the difficulty to explore the brain in a flying insect. Conversely, it is possible to have access to the brain with tethered bees but, until now, no studies explored visual learning. To bypass this limitation, our aim was to establish a virtual reality device to test visual learning in tethered bees. First, bees were tested for their abilities to learn to discriminate colors according to the reinforcement associated to each of them. These experiments allowed to highlight the role of the active vision in virtual reality and the importance of phototaxis in this kind of device. Driven by these good results, we explored the non- elementary visual learning in bees and, more specifically, the negative patterning. The results suggest that bees were able to resolve this task in virtual reality despite its complexity. Finally, using the protocol of color discrimination, the brain activation has been explored during a color memory recall thanks to a quantification of immediate early genes considered as neural markers. This thesis provides two solid virtual reality protocols to study elementary and non-elementary visual learning in honey bees. This constitutes a huge advance and will allow to go further towards the understanding of the neural bases of simple and complex visual learning.

Made available in DSpace on 2016-03-15T19:31:14Z (GMT). No. of bitstreams: 1 Gerson Luis Russo Moyses.PDF: 1823083 bytes, checksum: e67dbecac4ede2927a680c9325ad2a4e (MD5) Previous issue date: 2007-08-03 / Fundo Mackenzie de Pesquisa / The demand management is an emerging theme in the chain management knowledge field. What is aimed with the demand management is the fast and adequate integration of the needs originated from the market to the suppliers in a way to strategically balance and align the demand with the operacional capacity throught the supply chain and, consequently, the competitive advantage. However, with the market dynamic in which the clients are even more demanding and the commercial exchange regulations are less restrict, the alignment of the demand with the supply chain progressively face progressive difficulties. Because of that, this research had as an objective to verify alignment among the demand management, operational capacity and financial and operational performance variables, in hotel companies of national and international funds, in operation in Brazil. For that, a theoretical model was developed, that considered these variables. The research was achieved in two stages. In the first one, considered exploratory and qualitative, the focus group technic was used to data collection. The data collection was treated by the contend analysis. With the results of this first step a questionnaire was elaborated, which was used in the next stage. In the second stage, through the data collection by means of a structured questionnaire it was intended to characterize the demand management, capacity management and the imediate chain variables in the searched hotels. From the total of sent questionnaires, 121 answers were turned back. The obtained data were treated by the descriptive statistics and by the tests: a) Kolmogorov-Smirnov, to verify the sample normality; b) Spearman s bivariated correlation analysis, in order to verify the alignment among the variables and; c) Mann-Whitney, to find if the variables that pertained to groups of hotels were distinct. The data which was submitted to the statistic treatment showed the following results: 1) when it was used the descriptive statistics, the luxury group hotels presented a higher frequency of answers, in the agreeable side of the scale and superior financial and operational performance if compared to the economic group hotels; 2) when it was used the bivariated correlation, the luxury group hotels showed a higher number of demand management, operational capacity and financial and operational performance variables, correlated, and financial and operational performance which was superior to the economic group hotels; 3) when it was used the added scale, the luxury group hotels superiority prevailed again, not only in management variables but also in achievement in relation to the economic group and; 4) besides, it was evidenced that 46,4% from the total of analyzed variables differed a group from the other. Considering these results, it can be concluded that there is evidence that the luxury hotels predominance offers a better feed back to the investors, demanding a more efficient management. At last, given the hospitality market dynamicity, it is suggested, to the continuity of this study, the deepening in the variable measures research that compound the demand management, operational capacity immediate supply chain and performance, in order to know exactly the hospitality service nuances, in the different categories. / A gestão da demanda é um tema emergente no campo de conhecimento da gestão da cadeia de suprimentos. O que se busca com a gestão da demanda é a rápida e adequada integração das necessidades originadas do mercado na direção dos fornecedores, de modo a balancear e alinhar estrategicamente a demanda com a capacidade operacional ao longo da cadeia de suprimentos e, por conseqüência, a vantagem competitiva. Não obstante, com a dinâmica dos mercados em que os clientes estão cada vez mais exigentes e as regulamentações das trocas comerciais menos restritivas, o alinhamento da demanda com a cadeia de suprimentos enfrentam dificuldades progressivas. Por conta disso, essa pesquisa teve por objetivo verificar o alinhamento entre as variáveis da gestão da demanda, capacidade operacional, cadeia de suprimentos imediata e desempenho financeiro e operacional em empresas hoteleiras de capital nacional e internacional, em operação no Brasil. Para tanto, foi desenvolvido um modelo teórico em que se considerou essas variáveis. A pesquisa foi realizada em duas etapas. Na primeira etapa, considerada exploratória e qualitativa, foi utilizada a técnica do grupo focal para a coleta de dados. Os dados coletados foram tratados pela análise de conteúdo. Com os resultados desta primeira etapa elaborou-se o questionário, utilizado na etapa seguinte. Na segunda etapa, mediante a coleta de dados por meio de questionário estruturado, procurou-se caracterizar as variáveis da gestão da demanda, capacidade operacional e da cadeia imediata nos hotéis pesquisados. Do total de questionários enviados aos gestores de hotéis, retornaram 121 respostas. Os dados coletados foram tratados pela estatística descritiva e pelos testes: a) Kolmogorov-Smirnov para verificar a normalidade da amostra; b) análise de correlação bivariada de Spearman para verificar o alinhamento entre as variáveis e; c) Mann-Whitney para verificar se as variáveis pertenciam a grupos de hotéis eram distintas. Os dados submetidos aos tratamentos estatísticos revelaram os seguintes resultados: 1) quando se utilizou da estatística descritiva, os hotéis do grupo luxo apresentaram maior freqüência de respostas, no lado concordante da escala e desempenho financeiro e operacional superior aos hotéis do grupo econômico ; 2) quando se utilizou da correlação bivariada, os hotéis do grupo luxo que apresentaram maior número de variáveis da gestão da demanda, capacidade operacional e imediata, correlacionadas e desempenho financeiro e operacional superior aos hotéis do grupo econômico ; 3) quando se utilizou da escala somada, novamente prevaleceu a superioridade dos hotéis do grupo luxo , tanto em variáveis de gestão como de desempenho em relação ao grupo econômico e; 4) além disso, foram evidenciados que 46,4% do total de variáveis analisadas diferenciavam um grupo de hotéis do outro. Por conta desses resultados pode-se concluir que existe evidência de que o predomínio de investimentos dos hotéis de luxo oferece maior retorno aos investidores, demandando uma administração mais eficiente. Por fim, dada a dinamicidade do mercado hoteleiro, sugere-se para a continuidade desse estudo, o aprofundamento na pesquisa das medidas das variáveis que compõem a gestão da demanda, capacidade operacional, cadeia de suprimento imediato e desempenho, para se conhecer exatamente as nuances do serviço hoteleiro, nas diferentes categorias.