Les skieurs et les skieuses de bosses constituent une communauté d’athlètes talentueux et exceptionnels au sein de la population sportive canadienne : ceux-ci ont remporté quatre médailles aux Jeux olympiques de Sotchi (2014) et leur absence du podium est atypique sur le circuit de la Coupe du monde. Comment ces skieurs et ces skieuses de bosses ont-ils développé une expertise leur permettant d’être parmi les meilleurs, sinon les meilleurs, au monde ? L’atteinte d’un niveau expert est attribuable à la conduite de pratiques délibérées dirigées par un professeur et visant à améliorer des habiletés critiques à la performance (Ericsson, Krampe et Tesch-Römer, 1993). Ces pratiques ont lieu en dehors des cours institutionnels (entraînements avec l’équipe de sport) (Ericsson et al., 1993). Le développement du talent (et de l’expertise) en sport résulterait d’une accumulation de pratiques délibérées et de jeux délibérés menés au cours de 10 années ou 10 000 heures (Memmert, Baker et Bertsch, 2010). Le jeu délibéré est un engagement précoce dans une activité physique intrinsèquement motivante qui procure une gratification immédiate ainsi qu’une expérience de plaisir (Côté et Hay, 2002). En ayant lieu à l’extérieur de l’institution sportive, ces pratiques et ces jeux sont invisibles au public, suggérant que d’autres formes d’activités existent. Dès lors, cette thèse investigue l’ensemble des situations d’apprentissage menées en dehors des équipes de ski de bosses par des skieurs/skieuses expert(e)s et prometteur(e)s canadiens/canadiennes. Cette thèse appliquée approfondit la contribution de ces situations d’apprentissage au développement de l’expertise et du talent au moyen du concept d’Activité privée, un outil conceptuel qui regroupe l’ensemble de ces situations. Notre méthodologie qualitative, rétrospective et ethnographique traduit le point de vue et l’expérience de ces skieurs et de ces skieuses provenant de la culture sportive spécifique (Darbon, 2002) du ski de bosses au Québec et au Canada. La première partie de la thèse met en évidence une variété de catégories d’activités privées qui apparaissent, disparaissent ou se maintiennent au cours du développement sportif. Ces activités privées correspondent non seulement à des pratiques et des jeux identifiés dans la littérature sur le développement de l’expertise et du talent (Côté, Erickson et Abernethy, 2013; Ericsson et al., 1993), mais également à des jeux contribuant au développement cognitif et moteur (Piaget, 1945). Les skieurs évoquent aussi des formes d’activités privées "Autres". La deuxième partie de la thèse montre que le choix et la mise en place des activités privées dépendent de la disponibilité des ressources environnementales (artefacts) et sociales, mais également du contexte spatio-temporel. La mise en place et le déroulement des activités privées sont subordonnés aux processus proximaux (Bronfenbrenner, 1977), c’est-à-dire aux étayages (Bruner, 1983a) de l’entourage (entraîneurs, parents, fratrie et coéquipiers) et aux moyens d’autorégulation (Zimmerman, 2000) de celles-ci. La troisième partie de la thèse démontre que le choix de l’activité privée à mener découle d’un désir (Ross, 1995), orienté vers une fin-en-vue (Dewey, 1938), et d’une valorisation pragmatique. Outre ces constats, le choix, la mise en place et le déroulement des activités privées sont orientés par une sensibilité à (Récopé, Rix-Lièvre, Kellin et Boyer, 2014) et un modèle de performance idéale propre à chaque skieur. La quatrième partie expose les bénéfices retirés des activités privées. Ces bénéfices retirés permettent au skieur de posséder des habiletés critiques (habiletés techniques, physiques, stratégiques, mentales, esthétiques, proprioceptives et visant la performance globale) lui permettant ainsi d’offrir une performance experte et talentueuse en compétition de ski de bosses. [...] / Canadian mogul skiers are a community of talented and exceptional athletes in the Canadian sporting community: they won four medals at the Sochi Olympics (2014) and their absence from the podium is atypical on the world Cup circuit. How did these mogul skiers develop an expertise which classified them among the best, if not the best, in the world? Expert people conduct deliberate practice aimed at improving performance-critical skills and these deliberate practices are supervised by an expert teacher (Ericsson, Krampe and Tesch-Römer, 1993. These practices take place outside of the sport institution (sports team’s training program) (Ericsson et al., 1993). The development of talent (and expertise) in sport would result from an accumulation of deliberate practices and deliberate play conducted over 10 years or 10,000 hours (Memmert, Baker and Bertsch, 2010). Deliberate play is an early commitment to intrinsically motivating physical activity that provides immediate gratification and enjoyment (Côté and Hay, 2002). By taking place outside the sports institution, these practices and plays are invisible to the public, suggesting that other forms of activity exist. Therefore, this thesis investigates all learning situations conducted outside of the mogul teams by experienced and promising Canadian male and female skiers. This applied thesis study in depth the contribution of these learning situations to the development of expertise and talent through the concept of Private Activity, a conceptual tool that includes all possible learning situations. Our qualitative, retrospective and ethnographic methodology reflects the point of view and the experience of these skiers coming from the specific sports culture (Darbon, 2002) of mogul skiing in Quebec and Canada. The first part of the thesis highlights a variety of categories of private activities that appear, disappear or is maintain in the course of the skier’s sport development. These private activities not only correspond to practices and plays identified in the literature on the development of expertise and talent (Côté, Erickson and Abernethy, 2013, Ericsson et al., 1993), but also to plays contributing to cognitive and motor development (Piaget, 1945). Skiers also evoke private activities we identified as "Others". The second part of the thesis shows that the choice and the implementation of private activities depend on the availability of environmental (artefacts) and social resources, but also on the spatial-temporal context. The implementation and conduct of private activities are subordinated to the proximal processes (Bronfenbrenner, 1977), that is to say the entourage’s scaffolding (Bruner, 1983a) (coaches, parents, siblings and teammates) and to the self-regulation (Zimmerman, 2000) means. The third part of the thesis demonstrates that the choice of the private activity to be carried out arises from a desire (Ross, 1995), directed towards a end-in-view (Dewey, 1938), and a pragmatic valorization. In addition to these findings, the choice, implementation and conduct of private activities are oriented by a sensibility to (Récopé, Rix-Lièvre, Kellin and Boyer, 2014) and an ideal performance model specific to each skier. The fourth part describes the benefits derived from the private activities. These benefits allow the skier to acquired critical skills (technical, physical, strategic, mental, aesthetic, proprioceptive, and overall performance skills) allowing him to achieve expert and talented performance in mogul skiing competition. A modeling of the concept of Private Activity to study the development of expertise in sport is proposed at the end of the four parts of the thesis. To conclude, the non identical trajectory [...]

Made available in DSpace on 2014-07-29T14:52:08Z (GMT). No. of bitstreams: 1 Tese Sclerotinia_Riccely - pre textual.pdf: 83822 bytes, checksum: 7f0c226c4852681fb38e300f649a6c93 (MD5) Previous issue date: 2012-06-29 / The soybean (Glycine max L. Merril) is the main cultivated species on the country, having an average productivity of 3,106 kg.ha-1 in an area of 24.2 million hectares, giving to Brazil the second place in world production. Among the factors that limit the yield, the profitability and the successful production of this legume, diseases are a highlight. Among them, the white mold, caused by Sclerotinia sclerotiorum (Lib.) of Bary, is gaining importance in the soybean fields on the Brazilian Cerrado . The control of this disease is being considered difficult due to the absence of resistant cultivars, fungus survival in soil during long periods, range of hosts, large number of ascospores produced by apothecium and their fast dissemination on relatively long distances from the source and survival in seeds on mycelial dormant form or sclerotia, contaminating the batches. This work had the aim to study the genetic variability of S. sclerotiorum populations; evaluate the aggressiveness of isolates in soybean culture; evaluate the sensitivity of isolates to fungicides, temperatures and light regime; select an inoculation method of S. sclerotiorum in soybean plants, efficient and practical and; characterize soybean cultivars for reaction to S. sclerotiorum. The experiments were conducted on the Escola de Agronomia e Engenharia de Alimentos da Universidade Federal de Goiás . The collection of isolates was obtained by collecting sclerotia in soybean plants in eight municipalities of the Brazilian Central Region, Silvânia GO, Anápolis GO, São Miguel do Passa Quatro GO, Água Fria GO, Montividiu GO, Chapadão do Sul MS, Uberlândia MG and Patrocínio MG. The tests of mycelial compatibility were performed in MPM (Modified Patterson s Medium) and in PDA (Potato Dextrose Agar) medium, having the mycelial reactions of compatibility and incompatibility evaluated seven days after incubation. Analyzes of mycelial compatibility were performed in each sampled municipality, with a number of 25 isolates, as well as among groups of mycelial compatibility of each municipality, totaling 31 isolates. To evaluation of aggressiveness, 21 isolates representing each group of mycelial compatibility, found in each studied locality, were inoculated by the tip method on the petiole in the cultivars M-SOY 7908 RR and BRSGO 7760 RR. The evaluations of lesion length on stem were made three and seven days after inoculation. The same 21 isolates used on aggressiveness experiments were evaluated for sensibility to fungicides fluopyram, boscalid, thiophanate methyl, carbedanzim, dimoxystrobin + boscalid, procymidone and fluazinam. Those isolates were also evaluated for sensibility on temperatures 10oC, 15oC, 20oC, 25oC and 30oC, in light regime conditions of 12 hours and continuous darkness. For selection of a inoculation method both efficient and practical, four inoculation methods were used in soybean cultivars M-SOY 7908 RR and BRS 7760 RR using only one isolate. The characterization of soybean cultivars regarding reaction to S. sclerotiorum was made by means of an aggressive isolate, selected on aggressiveness experiments, and by the tip method. In this experiment forty cultivars were evaluated in totally randomized design with 3 repetitions. In intrapopulation analysis, was verified that the genetic variability in S. sclerotiorum was low, while in interpopulation analysis, eight compatibility groups were found, one of the groups more aggressive than the other ones. There was significant difference among isolates for the aggressiveness in the two cultivars, being the M-SOY 7908 RR cultivar the most susceptible. The isolates were highly sensible to fungicides boscalid, carbendazim, dimoxystrobin + boscalid, procymidone, fluopyram and fluazinam, only the isolate SSUB 18 was moderately sensible to the fungicide fluopyram. Most of isolates had insensibility to the fungicide thiophanate methyl. The best temperature for mycelial growth of isolates was 25oC, regardless the light regime. The tip method of inoculation in petiole was efficient and practical for characterization of soybean cultivars for their reaction to S. sclerotiorum. There is varietal difference among soybean cultivars for resistance to white mold, being cultivars BRSGO 8460RR, BRSGO Ipameri and P98Y11 the most resistant ones, on the present study conditions. / A soja (Glycine max L. Merril) é a principal espécie cultivada no país, tendo produtividade média de 3.106 kg.ha-1 em uma área de 24,2 milhões de hectares, conferindo ao Brasil o segundo lugar na produção mundial. Dentre os fatores que limitam o rendimento, a lucratividade e o sucesso de produção desta leguminosa destacam-se as doenças. Dentre elas, o mofo branco, causado por Sclerotinia sclerotiorum (Lib.) de Bary, tem assumido importância nos campos de cultivo de soja no Cerrado brasileiro. O controle dessa doença tem sido considerado difícil em função da ausência de cultivares resistentes, sobrevivência do fungo no solo por longos períodos, ampla gama de hospedeiros, grande número de ascósporos produzidos por apotécio e sua rápida disseminação a distâncias relativamente longas a partir da fonte produtora e sobrevivência em sementes na forma de micélio dormente ou escleródios contaminando os lotes. Este trabalho teve como objetivo estudar a variabilidade genética de populações de S. sclerotiorum; avaliar a agressividade de isolados em plantas de soja; avaliar a sensibilidade de isolados à fungicidas, temperaturas e regime de luz; selecionar um método de inoculação de S. sclerotiorum em plantas de soja, eficiente e prático e; caracterizar cultivares de soja quanto à reação à S. sclerotiorum. Os experimentos foram conduzidos na Escola de Agronomia e Engenharia de Alimentos da Universidade Federal de Goiás. A coleção de isolados foi obtida por meio de coleta de escleródios em plantas de soja de oito municípios da região Central do Brasil, Silvânia GO, Anápolis GO, São Miguel do Passa Quatro GO, Água Fria GO, Montividiu GO, Chapadão do Sul MS, Uberlândia MG e Patrocínio MG. Os testes de compatibilidade micelial foram realizados em meio de cultura MPM (meio modificado de Patterson s) e meio de cultura BDA (Batata Dextrose Ágar), sendo as reações miceliais de compatibilidade e incompatibilidade avaliadas aos sete dias após a incubação. As análises de compatibilidade micelial foram realizadas dentro de cada município amostrado, com um número de 25 isolados, bem como entre os grupos de compatibilidade micelial de cada município, totalizando 31 isolados. Para avaliação de agressividade, 21 isolados representando cada grupo de compatibilidade micelial, encontrado em cada localidade estudada, foram inoculados pelo método da ponteira no pecíolo nas cultivares M-SOY 7908 RR e BRSGO 7760 RR. As avaliações do comprimento de lesão na haste foram realizadas aos três e sete dias após a inoculação. Os mesmos 21 isolados utilizados nos experimentos de agressividade foram avaliados quanto à sensibilidade aos fungicidas fluopyram, boscalid, tiofanato metílico, carbedazim, dimoxystrobina+boscalid, procimidone e fluazinam. Estes isolados também foram avaliados quanto à sensibilidade as temperaturas de 10oC, 15oC, 20oC, 25oC e 30oC, em condições de fotoperíodo por 12 horas e escuro contínuo. Para seleção de um método de inoculação eficiente e prático, quatro métodos de inoculação foram utilizados nas cultivares de soja M-SOY 7908 RR e BRS 7760 RR, utilizando-se apenas um isolado. A caracterização de cultivares de soja quanto à reação a S. sclerotiorum foi realizada por meio de um isolado agressivo, selecionado nos experimentos de agressividade, e pelo método de inoculação da ponteira. Neste experimento foram avaliadas quarenta cultivares em delineamento inteiramente casualizado com 3 repetições. Em análise intrapopulacional, verificou-se que a variabilidade genética em S. sclerotiorum foi baixa, enquanto que em análise interpopulacional, oito grupos de compatibilidade foram encontrados, sendo um grupo mais predominante do que os demais. Houve diferença significativa entre os isolados quanto à agressividade nas duas cultivares, sendo a cultivar M-SOY 7908 RR a mais suscetível. Os isolados foram altamente sensíveis aos fungicidas boscalid, carbendazim, dimoxystrobina+boscalid, procimidone, fluopyram e fluazinam, somente o isolado SSUB 18 que foi moderamente sensível ao fungicida fluopyram. A maioria dos isolados apresentou insensibilidade ao fungicida tiofanato metílico. A melhor temperatura para o crescimento micelial dos isolados foi 25oC, independentemente do regime de luz. O método de inoculação da ponteira no pecíolo foi eficiente e prático para caracterização de cultivares de soja quanto à reação a S. sclerotiorum. Existe diferença varietal entre as cultivares de soja quanto à resistência ao mofo branco, sendo que as cultivares BRSGO 8460RR, BRSGO Ipameri e P98Y11 foram as mais resistentes, nas condições do presente estudo.

Les biocapteurs sont utilisés quotidiennement pour déterminer la présence de molécules biologiques dans une matrice complexe, comme l’urine pour les tests de grossesses ou le sang pour les glucomètres. Les techniques courantes pour la détection des autres maladies nécessitent fréquemment le marquage de l’analyte avec une autre molécule, ce qui est à éviter pour fin de simplicité d’analyse. Ces travaux ont pour but la maximisation de la sensibilité d’une surface d’or ou d’argent nanotrouée, afin de permettre la détection de la liaison de molécules biologiques par résonance des plasmons de surface localisés (LSPR), en utilisant la spectroscopie de transmission. Un biocapteur portable, rapide et sans marquage pour quantifier des analytes d’intérêt médical ou environnemental pourrait être construit à partir de ces travaux. Dans l’objectif d’étudier de nombreuses configurations pour maximiser la sensibilité, le temps et le coût des méthodes de fabrication de nanostructures habituelles auraient limité le nombre de surfaces nanotrouées pouvant être étudiées. Un autre objectif du projet consiste donc au développement d’une technique de fabrication rapide de réseaux de nanotrous, et à moindres coûts, basée sur la lithographie de nanosphères (NSL) et sur la gravure au plasma à l’oxygène (RIE). La sensibilité à la variation d’indice de réfraction associée aux liaisons de molécules sur la surface du métal noble et la longueur d’onde d’excitation du plasmon de surface sont influencées par les caractéristiques des réseaux de nanotrous. Dans les travaux rapportés ici, la nature du métal utilisé, le diamètre ainsi que la périodicité des trous sont variés pour étudier leur influence sur les bandes LSPR du spectre en transmission pour maximiser cette sensibilité, visant la fabrication d’un biocapteur. Les surfaces d’argent, ayant un diamètre de nanotrous inférieur à 200 nm pour une périodicité de 450 nm et les nanotrous d’une périodicité de 650 nm démontre un potentiel de sensibilité supérieur. / Biosensors are used daily to determine the presence of biomolecules in a complex matrix, like urine for pregnancy test or blood with a glucometer. The usual biodetection methods require the addition of a tag on the analyte, which is to be avoided to design a simple analytical method. The objective of this work is to maximize the sensitivity of a gold or silver nanohole arrays to detect the biomolecules liaisons close to the metal surface by localized surface plasmon resonance (LSPR) in transmission spectroscopy. A portable and effective biosensor to quantify analytes could be built based on this work, without a tagging step. To achieve the objective of evaluating numerous configurations for maximal sensitivity, the time and cost of the usual nanostructures fabrication methods would have limited the number of nanohole arrays in metal surface that could have been studied in this project. This fact motivated another objective of this project, the development of a fast and low cost fabrication method for nanohole arrays using nanospheres lithography (NSL) followed by reactive ions etching (RIE). The plasmon sensitivity and wavelength excitation are influenced by the nanohole arrays characteristics. In the work presented here, the chemical composition of the metal surface, the diameter and the periodicity of the nanohole arrays are shown to the influence the LSPR bands. The transmission maximum and minimum position of some LSPR bands are sensitive to refractive index change, which can be exploited in a biosensor format to detect biomolecules. The optimization of these nanohole arrays characteristics allows the maximization of this sensitivity to build a biosensor. The best index refraction sensitive results were with silver surfaces, with nanohole diameters smaller than 200 nm for a periodicity of 450 nm and the nanoholes with a periodicity of 650 nm show a potential for an increased sensitivity.

Les biocapteurs sont utilisés quotidiennement pour déterminer la présence de molécules biologiques dans une matrice complexe, comme l’urine pour les tests de grossesses ou le sang pour les glucomètres. Les techniques courantes pour la détection des autres maladies nécessitent fréquemment le marquage de l’analyte avec une autre molécule, ce qui est à éviter pour fin de simplicité d’analyse. Ces travaux ont pour but la maximisation de la sensibilité d’une surface d’or ou d’argent nanotrouée, afin de permettre la détection de la liaison de molécules biologiques par résonance des plasmons de surface localisés (LSPR), en utilisant la spectroscopie de transmission. Un biocapteur portable, rapide et sans marquage pour quantifier des analytes d’intérêt médical ou environnemental pourrait être construit à partir de ces travaux. Dans l’objectif d’étudier de nombreuses configurations pour maximiser la sensibilité, le temps et le coût des méthodes de fabrication de nanostructures habituelles auraient limité le nombre de surfaces nanotrouées pouvant être étudiées. Un autre objectif du projet consiste donc au développement d’une technique de fabrication rapide de réseaux de nanotrous, et à moindres coûts, basée sur la lithographie de nanosphères (NSL) et sur la gravure au plasma à l’oxygène (RIE). La sensibilité à la variation d’indice de réfraction associée aux liaisons de molécules sur la surface du métal noble et la longueur d’onde d’excitation du plasmon de surface sont influencées par les caractéristiques des réseaux de nanotrous. Dans les travaux rapportés ici, la nature du métal utilisé, le diamètre ainsi que la périodicité des trous sont variés pour étudier leur influence sur les bandes LSPR du spectre en transmission pour maximiser cette sensibilité, visant la fabrication d’un biocapteur. Les surfaces d’argent, ayant un diamètre de nanotrous inférieur à 200 nm pour une périodicité de 450 nm et les nanotrous d’une périodicité de 650 nm démontre un potentiel de sensibilité supérieur. / Biosensors are used daily to determine the presence of biomolecules in a complex matrix, like urine for pregnancy test or blood with a glucometer. The usual biodetection methods require the addition of a tag on the analyte, which is to be avoided to design a simple analytical method. The objective of this work is to maximize the sensitivity of a gold or silver nanohole arrays to detect the biomolecules liaisons close to the metal surface by localized surface plasmon resonance (LSPR) in transmission spectroscopy. A portable and effective biosensor to quantify analytes could be built based on this work, without a tagging step. To achieve the objective of evaluating numerous configurations for maximal sensitivity, the time and cost of the usual nanostructures fabrication methods would have limited the number of nanohole arrays in metal surface that could have been studied in this project. This fact motivated another objective of this project, the development of a fast and low cost fabrication method for nanohole arrays using nanospheres lithography (NSL) followed by reactive ions etching (RIE). The plasmon sensitivity and wavelength excitation are influenced by the nanohole arrays characteristics. In the work presented here, the chemical composition of the metal surface, the diameter and the periodicity of the nanohole arrays are shown to the influence the LSPR bands. The transmission maximum and minimum position of some LSPR bands are sensitive to refractive index change, which can be exploited in a biosensor format to detect biomolecules. The optimization of these nanohole arrays characteristics allows the maximization of this sensitivity to build a biosensor. The best index refraction sensitive results were with silver surfaces, with nanohole diameters smaller than 200 nm for a periodicity of 450 nm and the nanoholes with a periodicity of 650 nm show a potential for an increased sensitivity.