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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.
71

Analysis of Angiotensin II Receptor Subtypes in Individual Rat Brain Nuclei

Rowe, B. P., Saylor, D. L., Speth, R. C. 01 January 1992 (has links)
Previous studies have used new angiotensin II (AII) receptor subtype selective compounds to localize AII receptor subtypes within discrete rat brain nuclei. The purpose of this autoradiographic study was to extend these preliminary findings and provide a comprehensive analysis of AII binding sites in 22 rat brain nuclei and the anterior pituitary, to include estimates of the binding affinity for 125I sar1 ile8 AII (125I SIAII) at each nucleus, and determine the fractional distribution of each subtype at each nucleus. Estimates of K(D), in separate experiments revealed that AT1 nuclei had a consistently higher affinity for 125I SIAII than AT2 nuclei (0.66 vs. 2.55 nM). Displacement of subsaturating concentrations of 125I SIAII by 10-8-10-4 M DuP753 (selective for the AT1 subtype) or PD123177 (selective for the AT2 subtype) indicated that approximately half of the brain regions surveyed contained predominantly AT1 sites and half contained predominantly AT2 sites. Binding was partially displaced by both compounds in several regions and two site analyses were performed to estimate the distribution of subtypes within each nucleus. The data were then corrected for differential occupancy by 125I SIAII. Brain nuclei associated with cardiovascular or dipsogenic actions of AII, e.g., subfornical organ, organum vasculosum of the lamina terminalis, median preoptic nucleus, nucleus of the solitary tract and area postrema, contained pure, or almost pure, populations of AT1 receptors. The functions of AII in brain regions containing predominantly AT2 binding sites, e.g., thalamus, colliculi, inferior olive and locus ceruleus, remain undefined. Thus, AII binding sites in the rat brain have been differentiated into two subtypes with similar characteristics to those reported in peripheral tissues. However, the unexpected finding that they can be differentiated on the basis of their affinity for 125I SIAII raises questions concerning their coidentity with peripheral receptor subtypes.
72

Konsekvensanalys av olika förändringar i intäktsrams-regleringen avseende hänsyn till leveranssäkerhet / Analyses of changes in the regulatory framework with respect to security of supply

Majlund, Åsa January 2018 (has links)
The distribution of electricity is a natural monopoly. The infrastructure of the electricity grid is divided into areas and the distribution system operator (DSO) has concession for the distribution of the defined area. The concession is governed by laws and regulation.The Swedish Energy Markets Inspectorate (Ei) is the national regulatory authority. The continuity of supply of electricity is a part of the regulation. The incentive is given by a revenue cap regulation which may result in a reward or penalty.The performance indicators are a measure of the continuity of supply and used in the calculation of the revenue cap regulation.The Master thesis aims to specify the possible consequences for the electricity distribution system operators and their customers utilizing the electricity grid in case of a change of the current methods used to measure the continuity of supply in Sweden.With the current methods, the Ei regulation for year 2016-2019, is the continuity of supply in the local electrical grid estimated from a view where each disruption is treated equal and therefore is SAIFI and SAIDI used. In the regional electrical grid is another method used to measure the continuity of supply, estimated from a view where the loss of supplied energy is considered, therefore uses PNS and ENS. In the documentation is the term ILE used for ENS and ILEffekt for PNS.The Master thesis is constructed to analyze new performance indicators for the local and regional distribution grid. The new performance indicator is the mathematically instrument to measure the continuity of supply and is supported by analytically advantages and disadvantages.The result shows the choice of performance indicators cause a great impact in the revenue cap regulation. AIT, AIF corresponds to ENS and PNS, respectively, divided by power. The three most important results are given by:1. Mathematical and theoretical results show that ENS, PNS are not good indicators individually or in combination with SAIDI, SAIFI and CEMI4 as power consumption within each customer group varies in the local electrical grid.In the regional electrical grid, power consumption may also vary between the norm period and the supervisory period, which means that ENS, PNS can sometimes be misleading.2. The inclusion of power disruption over 12 hours generate stronger incentives in the regulation. Because it requires long term planning to avoid interruptions exceeding 12 hours. The difference is shown mainly in local electrical grid with the indicators SAIDI, SAIFI and CEMI4 and gives a slight increase in rewards in the regulation. This affects the DSO’s and their customers with a marginal difference.3. In the short term, the introduction of AIT, AIF as quality indicators means that customers who consume more power within their customer group get higher-value interruptions. An interruption of a high-consumption customer would then be prioritized compared to a customer with a lower consumption. One way to counteract this is to use CEMI4, in order to capture these customers' interruptions in the regulation.In the long term, the regulation does not become cyclically sensitive, meaning that reasonable rewards or penalties are made. This should benefit a long-term planning of the electrical grid, as the DSO’s do not have to compensate for this. / Det elektriska distributionsnätet är ett naturligt monopol. Infrastrukturen av nätet är uppdelat i områden och där nätägaren har nätkoncession för området som omfattas. Koncessionen är styrd av lagar och reglering.Energimarknadsinspektionen (Ei) är en tillsynsmyndighet som arbetar med uppdrag från regeringen. En del av tillsyn för energimarknaden, är reglering av leveranssäkerhet i det elektriska distributionsnätet. Incitamentet i regleringen ges av intäktsramens begränsning vilket kan resultera i en ökning eller minskning av intäktsramen.Kvalitetsindikatorer är ett matematiskt verktyg för att mäta leveranssäkerhet och används i regleringen av intäktsramen.Examensarbetet syftar till att synliggöra de möjliga konsekvenserna för nätföretagen respektive deras kunder av olika förändringar av de mätmetoder som används för att uppskatta leveranssäkerhet.De mätmetoder som används styrs av indikatorer. Indikatorer som mäter antal avbrott per totalt antal kunder kallas SAIFI. Indikatorer som mäter tid för dessa avbrott per totalt antal kunder kallas SAIDI. En annan metod är att de ingående indikatorerna ska mäta icke levererad energi eller effekt och då kallas de ILE respektive ILEffekt.Energimarknadsinspektionen har inför reglerperioden år 2016-2019 tillämpat SAIDI och SAIFI för kunder kopplade till lokalnät och ILE och ILEffekt för kunder och gränspunkter inom regionnätetExamensarbetet är utformat för att analysera nya typer av kvalitetsindikatorer i lokalnät och regionnät. De nya kvalitetsindikatorerna är olika matematiska verktyg för att mäta leveranssäkerheten och motiveras med analytiska för- och nackdelar.Resultatet visar att valet av indikator har stor betydelse i intäktsramens reglering. AIT, AIF motsvarar ILE respektive ILEffekt dividerat med effekt. De tre viktigaste resultaten ges av:1. Matematiska och teoretiska resultat visar att ILE, ILEffekt är inte bra indikatorer enskilt eller i kombination med SAIDI, SAIFI och CEMI4 då effektförbrukningen inom varje kundgrupp varierar för lokalnät.I regionnät så kan effektförbrukningen också variera mellan normperiod och tillsynsperiod vilket ger att ILE, ILEffekt ibland kan bli missvisande.2. Avbrott över 12 timmar genererar ett starkare incitament i regleringen. Eftersom det kräver långsiktig planering för att undvika avbrott som överstiger 12 timmar. Skillnaden visas främst i lokalnät med indikatorerna SAIDI, SAIFI och CEMI4 och ger en svag höjning av tillägg i regleringen sett på en systemnivå. Det påverkar nätföretagen och deras kunder med en marginell skillnad.3. På kort sikt innebär införandet av AIT, AIF som kvalitetsindikatorer att de kunder som förbrukar mer inom sin kundgrupp får högre värderade avbrott. Ett avbrott hos en kund med hög förbrukning skulle då prioriteras före en kund med lägre förbrukning. Ett sätt att motverka detta är att använda CEMI4 för att fånga upp dessa kunders avbrott i regleringen.På lång sikt innebär det att regleringen inte blir konjunkturkänslig, vilket innebär att rimliga tillägg eller avdrag görs. Det borde gynna en långsiktig planering av elnätet då elnätsföretagen inte behöver kompensera för detta inom regionnäten och lokalnäten.
73

The Waltz on the Seine

Kang, Jennifer J. 10 November 2000 (has links)
The desire to recognize and celebrate a forgotten artist and her work presents an opportunity for an investigation into the meeting of art and architecture. The dialogue between these two entities highlights the complexity of exhibiting works of art within a space of architectural integrity. The challenge is to successfully address both the art and the architecture in order to achieve a relationship that is mutually beneficial and equally powerful. This thesis investigates the transcendent themes created in such a dialogue. An innovative approach creates opportunities for extraordinary spatial experiences of the architecture and the artwork itself while addressing the challenges proposed by the site, one that has tremendous historical and cultural significance. The ultimate goal is a place where the architectural conditions provide a canvas for the acknowledgment and celebration of the artistic endeavors. / Master of Architecture
74

La " fabrique péri-urbaine ", système d'acteurs et production des ensembles pavillonnaires dans la Grande Couronne francilienne.

Callen, Delphine 08 November 2011 (has links) (PDF)
Les périphéries des grandes métropoles présentent des paysages facilement reconnaissables : maisons roses autour de rues en boucle ou en impasse... Ces ensembles pavillonnaires apparaissent comme une "image-type" de l'étalement urbain et sont souvent "accusés" d'uniformiser les paysages, de renforcer l'homogénéisation sociale et la ségrégation spatiale. En Ile-de-France, ces ensembles résultent souvent d'opérations groupées produites par un promoteur immobilier qui en réalise toutes les étapes de façon intégrée. Traditionnellement local, le secteur de la promotion immobilière s'est concentré et internationalisé au cours des vingt dernières années. Nous faisons l'hypothèse que le développement des grands groupes a des conséquences sur l'organisation du système de production des ensembles pavillonnaires, sur les manières de faire des différents acteurs et qu'il a une influence sur la morphologie et, en particulier, sur l'homogénéité de ces ensembles. Ces réflexions s'inscrivent dans un cadre plus large consistant à savoir jusqu'à quel point la mondialisation du secteur immobilier peut conduire à l'uniformisation des villes et des pratiques d'habiter. Nous cherchons à comprendre dans quelle mesure les transformations des différents acteurs de la production, les conditions de la " fabrique " périurbaine, liées au contexte de mondialisation et de métropolisation, ont un rôle sur les types d'espaces produits.
75

Acquisition du kreol mauricien et du français et construction du discours à travers l’analyse de productions orales d’enfants plurilingues mauriciens : la référence aux entités / The acquisition of Mauritian Creole and French and discourse construction through the analysis of oral productions of multilingual Mauritian children : the reference to entities

Florigny, Guilhem 14 December 2010 (has links)
L’Ile Maurice est une société complexe où se côtoient un grand nombre de langues : l’anglais et le français, langues administratives, sont apprises dès la première année du cycle primaire tandis que le kreol mauricien (KM), L1 de plus de 85% de la population, n’y joue aucun rôle à ce jour. C’est dans ce contexte que nous avons choisi d’analyser des productions orales en français et en KM d’enfants de deux groupes d’âge (6-7 ans et 8-9 ans), nos enquêtes ayant été faites dans des zones géographiques présentant des contextes socioculturels et linguistiques différents. Notre corpus est ainsi constitué d’environ 200 récits dans ces deux langues, obtenus à partir de la planche connue comme “Les oisillons”. Nous proposons ainsi une analyse détaillée des moyens mis en œuvre dans la référence aux entités, y compris des constructions possessives. Ceci nous mènera à constater avant tout qu’il existe une grande variabilité dans les productions, autant entre les langues que les zones géographiques. Nous remarquerons que l’acquisition du français est plus aboutie en zone urbaine que rurale tandis que le constat inverse s’appliquera au KM. Cette analyse mettra à jour deux conceptualisations de la tâche à accomplir (description et récit) qui montreront des degrés de variation concernant l’acquisition du genre et du nombre, ainsi que de l’utilisation du démonstratif, des pronoms, des noms nus, des possessifs et des compléments du nom. L’acquisition du français se révèlera alors tributaire d’un manque d’exposition à cette langue, de même qu’à l’influence du KM et de la variété locale de français. / Mauritius is a complex society where a wide range of languages are in compétition : whereas English and French, the administrative languages, are learnt from the first year of primary education, Mauritian Kreol (MK), the L1 of almost 85% of the population, has no part whatsoever to play in the system. Our analysis is focused on oral productions in French and MK from children of two age-groups (6-7 and 8-9 years old), coming from different sociocultural and linguistic backgrounds. 200 oral productions constitute our data, both in French and MK, collected from the task of retelling a story from drawings, known as « Les oisillons ». We have produced a detailed analysis of the means used by these children in the reference to entities including possessive structures. This has brought us to acknowledge that there is a huge variability in the productions, between the two languages as well as between the geographical zones. We have noticed that children in urban context reach a higher level of acquisition in French than those living in rural areas, whereas it is exactly the opposite when it comes to MK. This analysis also shows two conceptualisations of the tasks (description and narrative), which bring to light a high degree of variability as regards to the acquisition of gender and number, as well as that of demonstratives, pronouns, bare names, possessive determiners and constructions. The acquisition of French then appears as highly influenced by a lack of exposure to that language, as well as the influence of MK and the local variety of French.
76

Produção de leite de ovelhas da raça Santa Inês e mestiças F1 e desempenho de suas progênies resultantes do cruzamento com carneiros da raça Dorper / Milk yield of Santa Inês and crossbred ewes and performance of their progeny after mating with Dorper rams

Meneghini, Rafael Cedric Moller 18 June 2010 (has links)
Dois experimentos foram realizados para avaliar o desempenho de ovelhas Santa Inês e mestiças F1 com machos de raças de corte e de suas crias obtidas do cruzamento com carneiros da raça Dorper. No experimento 1, setenta e cinco borregas ( 15 da raça Santa Inês (SI), 15 ½Dorper + ½SI, 15 ½Ile de France + ½SI, 15 ½Suffolk + ½SI e 15 ½Texel + ½SI foram acasaladas com carneiros da raça Dorper e avaliadas quanto ao seu desempenho na parição e lactação. Foram avaliados o número de crias nascidas/fêmea parida, peso de nascimento, % de desmama, consumo de MS das ovelhas, produção e composição do leite, escore de condição corporal, concentração de ácidos graxos não-esterificados e desempenho das crias. A produção de leite foi estimada semanalmente, da segunda à oitava semana de lactação. Os cordeiros foram separados das mães as quais receberam, via endovenosa, 10 UI de oxitocina para permitir a ejeção do leite que foi removido por ordenha mecânica. Após 3h, o procedimento de ordenha foi repetido e a produção de leite foi registrada e uma amostra coletada para posterior determinação da composição. Ovelhas SI apresentaram maior (P<0,05) CMS relativo ao peso corporal do que ovelhas ½DO, ½IF e ½SK. Ovelhas ½DO produziram mais gordura, sólidos totais (ST) e leite corrigido para gordura (LCG) que ovelhas ½IF. Os teores de gordura e de ST no leite das ovelhas ½DO foram maiores (P<0,05) do que no das ½TX. Ovelhas ½TX desmamaram mais kg de cordeiros do que as SI (27,2 kg vs. 17,3 kg). Cordeiros ¼TX apresentaram GMD maior (P<0,05) que os ¾DO (283 g vs. 229 g). No experimento 2, foram avaliados o desempenho e a carcaça de cordeiros mestiços ½DO + ½SI (½SI), ¾DO + ¼SI (¾DO), ½DO + ¼IF + ¼SI (¼IF), ½DO + ¼SK + ¼SI (¼SK) e ½DO + ¼TX + ¼SI (¼TX) confinados sendo alimentados com ração contendo 90% de concentrado e 10% de feno. Os cordeiros mestiços entraram no confinamento com idade inicial média de 75 dias. Não houve diferença entre as médias de idade ao abate, peso no início do confinamento, peso no abate, consumo de matéria seca, ganho de peso médio diário, eficiência alimentar, peso de carcaça quente, peso de carcaça fria, rendimento de carcaça quente, rendimento de carcaça fria, área de olho de lombo, espessura de gordura subcutânea, alturas torácicas interna e externa, perímetro e comprimento de pernil, espessura de parede corporal, pesos e rendimentos dos cortes cárneos comerciais. Cordeiros do genótipo ¾DO apresentam maior perda por resfriamento de carcaça que os do genótipo ½SI. Cordeiros do genótipo ¼SK apresentam maior comprimento de carcaça que os cordeiros mestiços ¼TX. / Two experiments were performed to evaluate the performance of Santa Inês and F1 crossbred ewes and their lambs obtained by mating the ewes to Dorper rams. In Experiment 1- Seventy-five ewe lambs (15 Santa Inês (SI), 15 ½Dorper+½SI, 15 ½Ile de France+½SI, 15 ½Suffolk+½SI e 15 ½Texel+½SI) were mated to Dorper rams and evaluated during lambing and lactation. Number of lambs born/ewe, birth weight, weaning %, ewess DMI, milk yield, milk composition, body condition score, non- esterified fatty acids and lamb performance were evaluated. Milk production was measured every 7 d, from the second to the eighth week of lactation. Ewes were separated from lambs, oxytocin (10 IU) was infused, i.v., to stimulate milk letdown, and ewes were mechanically milked. After 3 h, the procedure was repeated and milk production was recorded and a sample collected for milk composition analysis. SI ewes showed higher (P<0.05) DMI as % of BW when compared to ½DO, ½IF and ½SK. A higher milk fat, total solids and fat corrected milk was observed for ½DO than ½IF. ½TX ewes produced more kg of weaned lambs than SI (27.2 kg vs. 17.3 kg). ADG for ¼TX lambs was higher (P<0.05) than ¾DO (283 g vs.229 g). In Experiment 2 Forty-eight lambs were used to evaluate the performance and carcass traits. Crossbred lambs were: ½DO + ½SI (½SI), ¾DO + ¼SI (¾DO), ½DO + ¼IF + ¼SI (¼IF), ½DO + ¼SK + ¼SI (¼SK) e ½DO + ¼TX + ¼SI (¼TX) feedloted and fed diets containing 90% concentrate and 10% hay. Lambs were housed individually and the slaughter target weight was 37 kg. Lambs were 75 days old at begining of the feedlot. There was no difference (P>0.05) on slaughter weight and age, starting weight at feedlot, dry matter intake (DMI), average daily gain (ADG), feed efficiency (FE), hot carcass weight, chilled carcass weight, dressing percentage, Longissimus muscle area, back fat, carcass measures and retail cuts yield. Lambs ¾DO had greater chilling losses when compared to ½SI. Lambs ¼SK showed greater carcass lenght when compared to ¼TX. Crossbred lambs evaluated showed similar performance (ADG, DMI, FE) and carcass characteristics except for carcass lenght. Crossbreeding meat type sheep is an interesting strategy to obtain lambs with desirable performance and carcass quality.
77

La clé des champs : enclavement et immunité territoriale de l'exploitation pétrolière en Afrique centrale (Tchad, Guinée Équatoriale, São Tomé et Príncipe) / Enclosing and territorial immunity of oil production areas in central Africa (Chad, Equatorial Guinea, São Tomé and Príncipe)

Donner, Nicolas 01 December 2014 (has links)
La présente thèse propose de réfléchir au « statut territorial » des espaces de la production pétrolière en Afrique centrale. Et ce en explorant d’abord – derrière les évidences d’un « enclavement » ordinairement admis de ces espaces (mais sans que celui-ci soit véritablement réfléchi) – leurs modes de production architecturaux : à la fois ceux des « enclaves pétrolières » en tant que telles, que l’on proposera de théoriser en tant qu’« îles artificielles » en les réfléchissant au vaste miroir des constructions techniques humaines, et ceux des systèmes spatiaux qui les portent : architectures internationales dont les « enclaves » apparaissent comme autant de clés de voûte – signalant alors cette croissante tension qu’aiguise le monde contemporain entre le développement d’interdépendances et de compénétrations territoriales de plus en plus vitales, et la persistance et la continuation – également fondamentale – du découpage de la scène internationale en unités territoriales souveraines. L’exploitation pétrolière – paradoxe dont on traquera la vérité – apparaissant autant comme un puissant facteur de construction de frontières internationales (dont on exposera quelques dynamiques en cours dans le golfe de Guinée) et comme une activité induisant et produisant différentes formes de découplages entre territoires étatiques et souverainetés, auxquelles l’exploitation et les investissements qui la sous-tendent supportent mal d’être assujettis. Ainsi explorerons-nous, au travers de l’étude des relations contractuelles nouées entre industriels et souverains, ainsi qu’au travers des techniques de financement telles que mobilisées dans le projet Tchad-Cameroun, comment l’exploitation pétrolière, parce qu’elle réclame une conséquente immunité à l’égard des risques qui pèsent sur elle (et au premier rang desquels figure le risque souverain), tend à produire des modes d’enclavement des territoires de l’exploitation. Car c’est ce que tend à démontrer cette thèse : que ces enclaves sont bel et bien des territoires, lesquels réclament toutefois d’être conceptualisés de façon à pouvoir concilier leurs dimensions « extraterritoriales » et leur toujours nécessaire ancrage dans la souveraineté territoriale étatique. / This thesis aims to conceptualize the oil production areas’ territorial status in central Africa. It first proposes to explore – behind the false evidence of an “enclave status” which is commonly accepted without being theorized – their architectural patterns: both those of the “oil enclaves” as such – which will be conceptualized as “artificial islands” by mirroring them with the vast domain of human technical constructions –, and those of the international spatial systems without which they could not exist – oil production spaces appearing as keystones of such systems. They thus highlight one of the contemporary world’s greatest tensions, which stand between the increasingly vital nature of international interdependences and territorial permeations, and the persistence and continuation – as well fundamental – of the territorial and sovereign partition of our world. Oil production – and we will inquire about the truth that hides such a paradox – concurrently appearing as a powerful factor in building international borders (which we will be discuss some current dynamics in the gulf of Guinea) and as creating various ways of unbundling territories and sovereignties, given that nor the activity nor its financial investors easily bear being at sovereign powers’ mercy. We will thus explore – through the contractual relations that intimately tie oil companies and sovereign powers, and through financing techniques such as those Exxon called up in the Chad-Cameroon project – how oil production – because it requires being consequently immunized against political and sovereigns' risks – tends to create various ways of territorial enclaving. And here is what this thesis seeks to demonstrate: that oil enclaves are territories – territories which claim to be conceptualized so as to reconcile their “extraterritorial” extent and their still crucial implant in the sovereign territory.
78

Étude histo-pathologique et moléculaire de la résistance des vanilliers (Vanilla spp., Orchidaceae) à Fusarium oxysporum f.sp. radicis-vanillae, agent de la pourriture des racines et des tiges / Histological and molecular approaches for resistance to Fusarium oxysporum f.sp. radicis-vanillae, causal agent of root and stem rot in Vanilla spp. (Orchidaceae)

Koyyappurath, Sayuj 08 July 2015 (has links)
La production de vanille (Vanilla planifolia, Orchidaceae) est limitée par la pourriture des racines et des tiges (PRT) provoquée par des champignons telluriques du genre Fusarium contre lesquels la lutte chimique ou prophylactique est inefficace. Ce travail décrit finement l'interaction entre les vanilliers et les Fusarium dans le but de développer la lutte génétique. L'analyse moléculaire (gène EF1α et IGS) et la détermination du pouvoir pathogène de 365 souches de Fusarium isolées de vanilliers à La Réunion et à Madagascar ont démontré que les souches pathogènes sur vanillier appartiennent presque toutes au complexe d'espèce F. oxysporum et ont une origine polyphylétique. Les observations en microscopie à champ large et multi-photons démontrent que la colonisation des racines débute au niveau des poils absorbants puis gagne le cortex, mais que le système vasculaire est épargné. Cela conduit à renommer l'agent pathogène en F. oxysporum f. sp. radicis-vanillae (Forv). Dans les interactions incompatibles (souche pathogène et vanillier résistant), l'épaississement et la lignification des parois de l'hypoderme, constitutive et induite par le champignon, joue un rôle significatif dans le blocage de l'invasion mycélienne. Le rôle important des composés phénoliques dans la résistance des vanilliers a été confirmé par les analyses d'expression différentielle de transcrits obtenus de novo par RNA-seq Illumina. Enfin, un test robuste de détermination in-vitro de la résistance à Forv a été validé et de nouvelles sources de résistance génétique à la PRT ont été identifiées. Nos résultats ouvrent des perspectives prometteuses pour la sélection de variétés améliorées de vanilliers. / Vanilla is a high value cash crop that is continuously demanded by the agri-food and cosmetics industries for its incomparable flavor. Most of vanilla comes from the cured fruits of V. planifolia G. Jackson, a hemi-epiphytic climbing orchid cultivated in the humid tropics. In all the countries were it is cultivated, the vanilla vines suffer from a root and stem rot (RSR) caused by the soil borne fungus Fusarium oxysporum which dramatically reduces plant production and the durability of plantations. No efficient control method is currently available for this disease. Sources of genetic resistance to RSR exist in few vanilla relatives, but so far no commercial resistant variety has been produced. The purpose of this thesis was to better describe the diversity and histopathology of the causal agent of RSR and to evaluate the potential sources of genetic resistance that could be used in breeding programs. In a first step, a collection of 377 single-spored Fusarium isolates recovered from rotten roots and stems during surveys conducted in 52 vanilla plots from Reunion Island, Madagascar and French Polynesia were characterised. Representative subsets of isolates were genotyped using the Elongation Factor 1α and Intergenic Spacer gene sequences. Their pathogenicity was assayed by root dip inoculation on the susceptible V. planifolia accession pla0001. Results showed that F. oxysporum was the principal species responsible for the disease in the field, although a few F. solani isolates showing slight pathogenicity were also isolated. Fusarium oxysporum isolates were highly polyphyletic regardless of geographic origin or pathogenicity. Remarkably, their pathogenicity varied in gradient between non- pathogenic (about 42% of isolates) to highly pathogenic (14%). In a second step, 254 vanilla accessions comprising 18 species and six types of hybrids were assessed for resistance to RSR in the field (natural inoculum) and in the lab (in-vitro plants inoculated with Fo072). The strong resistance to RSR of all V. pompona accessions and hybrids of V. planifolia X V. pompona or V. phaeantha, were confirmed, and novel sources of resistance to RSR were added including, V. bahiana, V. costariciensis and V. crenulata. Most of the V. planifolia accessions, V. ×tahitensis and V. odorata were susceptible to RSR. However, three inbreeds of V. planifolia showed a high level of resistance to Forv. To our knowledge this is the first report of resistance to RSR in V. planifolia accessions. For the 26 accessions evaluated in both conditions, a strong correlation was observed between long term (9 years) evaluation in the field and ratings on in-vitro plants at 15dpi. Thirdly, we monitored by wide field and multiphoton microscopy the root infection process and the responses of one susceptible accession (V. planifolia pla0001) and two resistant accessions (V. planifolia pla0020 and V. pompona pom0018) to challenge inoculation with the severe isolate Fo072. In the compatible interaction (Fo072 – pla0001) invasion started from penetration of hyphae emitted from germinated conidia in the hairy region of root rapidly colonizing the cortex but never expanded to the vascular bundles up to the 9th dpi. It was therefore suggested to prefix the forma specialis name of the causal agent of RSR with radicis to point out its non-vascular pathogenicity in vanilla. In the two incompatible interactions, the important role played by hypodermis cells for impeding the invasion of the cortex by Fo072 was demonstrated by specific staining and spectral analysis of lignin precursors. Both constitutive and pathogen induced defense mechanism were described in pla0020 and pom0018. The mechanisms included the deposition of lignin in the hypodermal cell wall, entrapment of hyphae in specific hypodemal cells and polyphenolics secretion in intercellular spaces. Further, a de novo transcriptome analysis was experimentedon 8 pooled samples.
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La géopolitique de la République de Maurice / The Geopolitics of the Republic of Mauritius

Osman, Shafick 06 November 2013 (has links)
Il s’agit d’une « photographie » géopolitique de la République de Maurice avec deux axes très précis : la géopolitique interne et la géopolitique externe du pays. L’analyse est faite à partir de faits essentiellement rapportés dans la presse mauricienne, si riche en diversité et commentaires. Puisant dans la profondeur historique pour essayer d’expliquer le présent, c’est le premier travail d’analyse et de réflexion sur la géopolitique de la jeune république mauricienne. La complexité des rapports entre les différents territoires (Rodrigues et Agaléga) avec l’île Maurice est expliquée, de même que les relations et positions d’ambiguïté avec la Grande-Bretagne (et les Etats-Unis) et la France sur les « contentieux » au sujet de l’archipel des Chagos et de Tromelin respectivement. Les rapports tendus entre les différentes communautés présentes à Maurice sont exposés, de même que la problématique de conversion de terres, souvent agricoles, en résidences de luxe pour étrangers fortunés et projets immobiliers d’envergure. La politique étrangère « neutre », propre à Maurice, est aussi examinée dans le cadre de sa géopolitique externe, de même que sa multiple appartenance aux organismes régionaux indianocéaniques et africains. De par sa « réussite économique » connue de l’étranger, Maurice ambitionne de devenir le centre de toutes choses dans la région et elle se propose d’être la passerelle financière entre l’Afrique et l’Asie. Ayant des liens « ombilicaux » avec l’Inde, Maurice est restée cependant pro-occidentale avec une nette poussée de la francophonie et un déclin de l’influence britannique. Africaine politiquement, Maurice s’oriente économiquement vers l’Asie. / The work is a ‘snapshot’ of the geopolitics of the Republic of Mauritius with a two-pronged approach: The Internal Geopolitics and the External Geopolitics of the country. The analysis made is from facts mainly reported in the Mauritian press, so rich in diversity and comments. Going down the historical depth to try to explain the present, it is the first work of analysis and reflection on the geopolitics of the young Mauritian republic.The complexity of the relationships between the different territories (Rodrigues and Agalega) with Mauritius Island is explained, as well as the relationships and ambiguous positions with Great Britain (and the United States) and France on the issues of the Chagos Archipelago and Tromelin respectively. The tense relationships between the different communities present in Mauritius are exposed, as well as the controversial issue of land conversion -often agricultural land- to luxury residences for wealthy foreigners and ambitious real estate projects. The ‘neutral’ foreign policy of Mauritius, so unique, is also examined in the context of its External Geopolitics, as well as its multiple belongings to regional organisations in the Indian Ocean and in Africa. Known abroad for its ‘economic success’, Mauritius aspires to become the regional hub of all possible things and it has positioned itself to be the financial gateway between Africa and Asia. Having ‘umbilical’ links with India, Mauritius has remained however pro-western with an impressive Francophone boost and a decline of the British influence. Politically African, Mauritius is now economically oriented towards Asia.
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Produção de leite de ovelhas da raça Santa Inês e mestiças F1 e desempenho de suas progênies resultantes do cruzamento com carneiros da raça Dorper / Milk yield of Santa Inês and crossbred ewes and performance of their progeny after mating with Dorper rams

Rafael Cedric Moller Meneghini 18 June 2010 (has links)
Dois experimentos foram realizados para avaliar o desempenho de ovelhas Santa Inês e mestiças F1 com machos de raças de corte e de suas crias obtidas do cruzamento com carneiros da raça Dorper. No experimento 1, setenta e cinco borregas ( 15 da raça Santa Inês (SI), 15 ½Dorper + ½SI, 15 ½Ile de France + ½SI, 15 ½Suffolk + ½SI e 15 ½Texel + ½SI foram acasaladas com carneiros da raça Dorper e avaliadas quanto ao seu desempenho na parição e lactação. Foram avaliados o número de crias nascidas/fêmea parida, peso de nascimento, % de desmama, consumo de MS das ovelhas, produção e composição do leite, escore de condição corporal, concentração de ácidos graxos não-esterificados e desempenho das crias. A produção de leite foi estimada semanalmente, da segunda à oitava semana de lactação. Os cordeiros foram separados das mães as quais receberam, via endovenosa, 10 UI de oxitocina para permitir a ejeção do leite que foi removido por ordenha mecânica. Após 3h, o procedimento de ordenha foi repetido e a produção de leite foi registrada e uma amostra coletada para posterior determinação da composição. Ovelhas SI apresentaram maior (P<0,05) CMS relativo ao peso corporal do que ovelhas ½DO, ½IF e ½SK. Ovelhas ½DO produziram mais gordura, sólidos totais (ST) e leite corrigido para gordura (LCG) que ovelhas ½IF. Os teores de gordura e de ST no leite das ovelhas ½DO foram maiores (P<0,05) do que no das ½TX. Ovelhas ½TX desmamaram mais kg de cordeiros do que as SI (27,2 kg vs. 17,3 kg). Cordeiros ¼TX apresentaram GMD maior (P<0,05) que os ¾DO (283 g vs. 229 g). No experimento 2, foram avaliados o desempenho e a carcaça de cordeiros mestiços ½DO + ½SI (½SI), ¾DO + ¼SI (¾DO), ½DO + ¼IF + ¼SI (¼IF), ½DO + ¼SK + ¼SI (¼SK) e ½DO + ¼TX + ¼SI (¼TX) confinados sendo alimentados com ração contendo 90% de concentrado e 10% de feno. Os cordeiros mestiços entraram no confinamento com idade inicial média de 75 dias. Não houve diferença entre as médias de idade ao abate, peso no início do confinamento, peso no abate, consumo de matéria seca, ganho de peso médio diário, eficiência alimentar, peso de carcaça quente, peso de carcaça fria, rendimento de carcaça quente, rendimento de carcaça fria, área de olho de lombo, espessura de gordura subcutânea, alturas torácicas interna e externa, perímetro e comprimento de pernil, espessura de parede corporal, pesos e rendimentos dos cortes cárneos comerciais. Cordeiros do genótipo ¾DO apresentam maior perda por resfriamento de carcaça que os do genótipo ½SI. Cordeiros do genótipo ¼SK apresentam maior comprimento de carcaça que os cordeiros mestiços ¼TX. / Two experiments were performed to evaluate the performance of Santa Inês and F1 crossbred ewes and their lambs obtained by mating the ewes to Dorper rams. In Experiment 1- Seventy-five ewe lambs (15 Santa Inês (SI), 15 ½Dorper+½SI, 15 ½Ile de France+½SI, 15 ½Suffolk+½SI e 15 ½Texel+½SI) were mated to Dorper rams and evaluated during lambing and lactation. Number of lambs born/ewe, birth weight, weaning %, ewess DMI, milk yield, milk composition, body condition score, non- esterified fatty acids and lamb performance were evaluated. Milk production was measured every 7 d, from the second to the eighth week of lactation. Ewes were separated from lambs, oxytocin (10 IU) was infused, i.v., to stimulate milk letdown, and ewes were mechanically milked. After 3 h, the procedure was repeated and milk production was recorded and a sample collected for milk composition analysis. SI ewes showed higher (P<0.05) DMI as % of BW when compared to ½DO, ½IF and ½SK. A higher milk fat, total solids and fat corrected milk was observed for ½DO than ½IF. ½TX ewes produced more kg of weaned lambs than SI (27.2 kg vs. 17.3 kg). ADG for ¼TX lambs was higher (P<0.05) than ¾DO (283 g vs.229 g). In Experiment 2 Forty-eight lambs were used to evaluate the performance and carcass traits. Crossbred lambs were: ½DO + ½SI (½SI), ¾DO + ¼SI (¾DO), ½DO + ¼IF + ¼SI (¼IF), ½DO + ¼SK + ¼SI (¼SK) e ½DO + ¼TX + ¼SI (¼TX) feedloted and fed diets containing 90% concentrate and 10% hay. Lambs were housed individually and the slaughter target weight was 37 kg. Lambs were 75 days old at begining of the feedlot. There was no difference (P>0.05) on slaughter weight and age, starting weight at feedlot, dry matter intake (DMI), average daily gain (ADG), feed efficiency (FE), hot carcass weight, chilled carcass weight, dressing percentage, Longissimus muscle area, back fat, carcass measures and retail cuts yield. Lambs ¾DO had greater chilling losses when compared to ½SI. Lambs ¼SK showed greater carcass lenght when compared to ¼TX. Crossbred lambs evaluated showed similar performance (ADG, DMI, FE) and carcass characteristics except for carcass lenght. Crossbreeding meat type sheep is an interesting strategy to obtain lambs with desirable performance and carcass quality.

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