Les radars à nuages sont des atouts indéniables pour la Prévision Numérique du Temps (PNT). De par leur petite longueur d’onde, ils possèdent une excellente sensibilité aux particules nuageuses et ils sont facilement déployables à bord de plates-formes mobiles. Cette thèse a permis d’évaluer l’apport des observations de radars à nuages pour la validation et l’initialisation de modèles de PNT à échelle kilométrique. Dans la première partie, un opérateur d’observation pour la réflectivité en bande W a été conçu en cohérence avec le schéma microphysique à un moment d'Arome, le modèle de PNT à échelle kilométrique de Météo-France, mais de façon suffisamment générale pour pouvoir être adapté à un autre modèle de PNT à échelle kilométrique. Il est adaptable pour des radars à visée verticale aéroportés ou au sol. Afin de dissocier les erreurs de positionnement des nuages prévus par Arome, de celles présentes dans l’opérateur d’observation, une nouvelle méthode de validation, appelée "la méthode de la colonne la plus ressemblante (CPR), a été élaborée. Cette méthode a été employée afin de valider et de calibrer l'opérateur d'observation en utilisant les profils de réflectivité collectés par le radar à nuages aéroporté Rasta dans des conditions variées durant la première période d’observations (SOP1) du programme international HyMeX, qui vise à améliorer notre compréhension du cycle de l'eau en méditerranée. La seconde partie s'est intéressée à l'apport respectif de l'assimilation de profils verticaux de réflectivité et de vents horizontaux mesurés par le radar à nuages Rasta dans le système d'assimilation variationnel tridimensionnel (3DVar) d'Arome. Le bénéfice apporté par des conditions thermodynamiques, via l'assimilation de la réflectivité en bande W, et dynamiques, via l'assimilation des profils de vents horizontaux, cohérentes dans l'état initial a également été étudié. Pour assimiler la réflectivité en bande W, la méthode d'assimilation "1D+3DVar", qui est opérationnelle dans Arome pour assimiler les réflectivités des radars de précipitation au sol, a été employée. La méthode de restitution bayésienne 1D de profils d'humidité a été validée avec des mesures d'humidité in situ indépendantes. Puis, les expériences d'assimilation ont été menées sur un événement fortement convectif, ainsi que sur une plus longue période de 45 jours. Les résultats suggèrent notamment que l'assimilation conjointe des profils de réflectivité en bande W et des profils verticaux de vents horizontaux permet d'améliorer les analyses d'humidité, mais suggèrent également une légère amélioration des prévisions des cumuls de précipitation

In field experiments conducted in northern Virginia during 1998, oils reduced photosynthesis, fruit maturity, and crop yield. Three applications of a 1.5% (v/v) oil/water emulsion were made to Chardonnay and Cabernet Sauvignon vine canopies at 6200 L/ha (Chardonnay) and 2440 L/ha (Cabernet Sauvignon). Net assimilation rate (NAR), soluble solids concentration (SSC), and berry size were reduced by oil treatments when compared to an untreated control. Also in 1998, a 1.5% (v/v) oil/water emulsion at 5550 L/ha and 4680 L/ha was applied to 23 wine grape cultivars. Eleven cultivars had significant foliar injury but injury was not related to reductions in fruit maturity. Experiments conducted in 1999 determined if reduced spray volumes or applications to only the fruit zone minimize reductions in NAR and SSC. Chardonnay and Cabernet Sauvignon were treated with JMS Stylet oil (1.5%) using 5600 L/ha or 1870 L/ha applied to the whole canopy or 930 L/ha applied to the fruit zone. The NAR of 5600 L/ha treated Cabernet Sauvignon was significantly lower than the NAR of control and other oil treatments on three measurement dates. The NAR of Chardonnay in the 5600 L/ha treatment was significantly lower than the NAR of control treatments in three measurements. Cabernet Sauvignon SSC was reduced by the 5600 L/ha and 1870 L/ha treatments, relative to the water treated control, on three sample dates but not at harvest. The SSC of Chardonnay in the 5600 L/ha treatment was reduced at harvest as compared to all other treatments. The SSC of Chardonnay in the 1870 and 930 L/ha treatments was reduced relative to the water control. Low volumes of oil caused less reduction in NAR and SSC; however, there are concerns about the efficacy of oils used at low volumes due to poor coverage. / Master of Science

Phytoplankton is at the basis of the marine food chain and therefore play a fundamental role in the ocean ecosystem. However, the large-scale phytoplankton dynamics of the Red Sea are not well understood yet, mainly due to the lack of historical in situ measurements. As a result, our knowledge in this area relies mostly on remotely-sensed observations and large-scale numerical marine ecosystem models. Models are very useful to identify the mechanisms driving the variations in chlorophyll concentration and have practical applications for fisheries operation and harmful algae blooms monitoring. Modelling approaches can be divided between physics- driven (dynamical) approaches, and data-driven (statistical) approaches. Dynamical models are based on a set of differential equations representing the transfer of energy and matter between different subsets of the biota, whereas statistical models identify relationships between variables based on statistical relations within the available data. The goal of this thesis is to develop, implement and test novel dynamical and statistical modelling approaches for studying and forecasting the variability of chlorophyll concentration in the Red Sea. These new models are evaluated in term of their ability to efficiently forecast and explain the regional chlorophyll variability. We also propose innovative synergistic strategies to combine data- and physics-driven approaches to further enhance chlorophyll forecasting capabilities and efficiency.

Adjusting socially and emotionally to a new cultural environment can be challenging for immigrants. Yet, the academic and behavioral performance of immigrant children can be enhanced when acculturative strategies are implemented in schools to address their unique cultural differences and needs. However, a scarcity of information exists pertaining to educational strategies to support acculturation of Haitian students, particularly those with disabilities. A qualitative case study was conducted to explore strategies that support acculturation of Haitian students with disabilities and the link between the use of acculturation strategies and student achievement from the perspectives of 3 regular education educators, 2 special education educators, 2 transition specialists, a school counselor, and a school psychologist at a high school in the northeastern United States. The bidimensional theory of acculturation provided the conceptual framework for this study. Qualitative data were collected by conducting semi-structured interviews with 9 secondary school educators. Purposeful sampling was used in this study as part of the qualitative approach. Data from interviews were coded and themes were developed consistent with the conceptual framework. Results were that most participants felt positively about cultural maintenance but expressed concern with their ability to meet the acculturative needs of Haitian students with disabilities. In addition, most participants were unable to identify specific acculturation strategies that they used to support Haitian students with disabilities beyond language acquisition resources. The findings of this study may be instrumental in the creation of school-based systems of support for educators and students to increase the social integration and academic achievement of immigrant children with and without disabilities.

京都大学 / 0048 / 新制・論文博士 / 博士(理学) / 乙第12830号 / 論理博第1541号 / 新制||理||1578(附属図書館) / 31368 / (主査)教授 余田 成男, 教授 石川 裕彦, 教授 向川 均 / 学位規則第4条第2項該当 / Doctor of Science / Kyoto University / DGAM

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<p> The experiments described in this thesis were performed to investigate the: 1. Role of nitrate in the growth of maize seedling and 2. Role of amino acids in the assimilation of nitrate by the growing embryo.</p> <p> Nitrate stimulated the germination of Zea mays L. seeds by 10 to 15 percent. Further growth of the embryo axis, up to 6 days, however, was not affected by nitrate. During the early growth of the seedling, endosperm nitrogen was able to support the requirements of the embryo for 6 to 8 days. After a lag of 2 days, the protein content of the embryo increased linearly up to 6 days at a rate of 597 μ g a day. Some increase was observed between 6 and 8 days also. After 8 days, the protein level of embryo plateaued. Addition of 10 mM nitrate caused an increase in the protein and total nitrogen of the embryo only after 6 days. The endosperm mutant of maize, opaque-2, also responded to the nitrate in the same way.</p> <p> The protein content of the primary leaves increased linearly between 5 and 7 days. After 7 days, there is no increase in the leaf protein. Nitrate increased the protein level of primary leaves by 25 percent after 7 days. It protected against the further loss of protein in mature leaf. These results suggest that the primary role of nitrate in the growth of maize seedlings is to prevent protein loss.</p> <p> Out of 8 amino acids tested individually, only lysine and to a lesser extent arginine, inhibited the induction of nitrate reductase in the maize root tips. Different ammonium salts had no effect on the induction of nitrate reductase. The initial rate of induction in opaque-2 mutant (high lysine) was lower than the wild type, W64A (low lysine). From a comparison of the rate of induction of nitrate reductase between young and mature leaf, it was suggested that the amino acid supply from the endosperm may inhibit the induction of nitrate reductase. In the young maize seedling, this effect of amino acids may be more effective in vivo and in this way the assimilation of exogenous nitrate could be restricted, when the endosperm amino acids are supporting the growth of the embryo.</p> / Thesis / Master of Science (MSc)

En stark politisk självständighet på kommunal nivå i Sverige kan innebära skillnader i målsättningar och förutsättningar för integration under olika mandatperioder och koalitioner. Denna uppsats undersöker integrationspolitikens strategier och vill således undersöka och jämföra hur partiernas årsplaner förhåller sig till det som i forskning definieras som integration. vi vill exemplifiera hur kommunala politiker i den valda kommunen arbetar med sin integrationspolitik, vilka likheter och skillnader finns det mellan olika majoritetsstyren i dess årsplaner? Strävar majoriteterna efter multikulturell politik, segregerad politik eller assimilerings politik? Materialet i studien som har analyserats är Eskilstuna kommuns majoritetspartiers årsplaner som ligger till grund för studien. I dessa årsplaner har vi fokuserat på att ta ut väsentliga delar som kan kopplas till integrationspolitik. Vi har utgått från Hermansson (1984) idékomplex “varat, ”börat” och görat” Begreppens utformning utgör majoriteternas likheter, skillnader och åtgärder för problemet. I vårt fall utgår vi från hur majoriteternas idéer kring integration formuleras. Vi kommer även att utgå från tre dimensioner, där vi vill diskutera hur årsplanerna förhåller sig i verkligheten till dessa dimensioner av integrationspolitik. Grunden för dimensionerna bygger på Carl Dahlströms integrationsmodeller som delas upp i tre komponenter assimilering, mångkulturalism samt segregationEn slutsats vi har kommit fram till i studien är att alla årsplaner ser en verklighetsbild som bygger på ett samhälle som är segregerat. Alla majoriteter är överens om att det finns ojämlikheter och skillnader i samhället som gör att olika individer inte har samma rättigheter, möjligheter och skyldigheter att delta i samhället. Vi ser även att alla partimajoriteter är överens om att man vill minska på dessa skillnader och vidta åtgärder för att detta ska ske. I detta steg börjar årsplanerna skilja sig åt där de strategiska målen och åtgärderna riktar sig åt olika håll.

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