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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.
241

Fixation des dunes dans le Sud-Est du Niger : évaluation de lefficacité de la barrière mécanique, espèces ligneuses adaptées et potentialités dinoculation mycorhizienne

Laminou Manzo, Ousmane 05 January 2010 (has links)
RESUME : Le Sud-Est du Niger est soumis au phénomène dérosion éolienne. Dans la zone de Gouré, les cuvettes oasiennes, principales sources de productions agricoles et de revenus, sont menacées de disparition à cause de lensablement. Des opérations de fixation de dunes sont entreprises pour sauver ce capital productif. Lévaluation de la technique de fixation mécanique des dunes utilisée dans la zone a montré que celle-ci est efficace dans la restauration écologique du milieu. Trois années après la mise en place des palissades anti-érosives, à base des branchages de Leptadenia pyrotechnica, une végétation spontanée, comprenant 58 espèces (20 familles), dont 17 pérennes, sétait installée à lintérieur du clayonnage, soit 42 espèces de plus que dans les zones non traitées. Au fil des ans, la composition floristique sest progressivement stabilisée, témoignant ainsi dune réduction notable des perturbations du milieu engendrées par laction érosive des vents. Dans une expérimentation de fixation biologique de dunes, sept espèces ligneuses, dont cinq autochtones (Acacia senegal, A. tortilis, A. nilotica, Bauhinia rufescens, Balanites aegyptiaca), et deux allochtones (Prosopis juliflora et P. chilensis) ont été testées. En pépinière, les espèces ont subi un stress hydrique par interruption darrosage durant six jours. Les taux dhydratation foliaire ont été déterminés, afin dévaluer leur capacité respective à limiter les pertes deau par transpiration. Dans un essai de terrain, les espèces ont été plantées sur un cordon dunaire, préfixé mécaniquement, en vue de tester leur aptitude à la stabilisation des dunes. Les taux de survie sur trois années ont été calculés et la croissance en hauteur mesurée. Les résultats en pépinière ont montré, quaprès six jours de stress hydrique, Acacia senegal, A. tortilis, Prosopis chilensis et A. nilotica sont les quatre espèces limitant le mieux les pertes en eau. Les résultats sur site ont montré que la meilleure combinaison en matière de fixation de dunes dans cette zone serait dassocier lespèce de Prosopis chilensis (fort taux de survie et croissance rapide) avec A. tortilis et/ou A. nilotica (survie et croissance relativement appréciables et intérêt économique plus important). Dans loptique dun essai dinoculation mycorhizienne, des échantillons de sols de Gouré ont été récoltés sous dix espèces ligneuses locales et exotiques, avec lobjectif didentifier les différents types de champignons mycorhiziens à arbuscules (CMA) et de produire un inoculum indigène par le biais de trois plantes-pièges locales ; le mil, le sorgho et le niébé. Les résultats ont mis en évidence la présence de deux familles de Glomales dans les sols du département de Gouré, Glomaceae (appartenant au genre Glomus) et Gigasporaceae. Avec plus de 56 % des spores, le genre Glomus est le plus abondant des Glomales identifiées et aussi le plus viable (55,80 % des spores vivantes). La croissance en hauteur des parties aériennes du sorgho et du niébé a été significativement stimulée par linoculation. Les trois cultures sont équivalentes dans le piégeage des spores. Un inoculum mycorhizien composite de souches indigènes a été produit à partir de cette culture sporale. Lefficacité de la mycorhization naturelle a été comparée à celles des apports de ce complexe mycorhizien indigène et du Glomus intraradices. Un substrat de culture naturel, non stérilisé, a été inoculé par le complexe mycorhizien de souches indigènes ou par du Glomus intraradices. Les effets de linoculation ont été observés sur cinq espèces ligneuses, dont trois Acacias (A. nilotica, A. tortilis, A. senegal), Bauhinia rufescens et Prosopis chilensis, en pépinière et en sol dunaire. En pépinière, les espèces ont subi un stress hydrique par interruption darrosage durant six jours. Les taux dhydratation foliaire ont été calculés, afin dévaluer les effets de la mycorhization sur la limitation des pertes deau par transpiration. Les différents taux de mycorhization ont été déterminés, ainsi que la croissance des plants et la production de la biomasse totale. Dans un essai de terrain, les espèces inoculées et non inoculées ont été plantées sur un cordon dunaire, préfixé mécaniquement, en vue dévaluer les effets des différents apports mycorhiziens au champ sur la croissance en hauteur des plants. Les résultats en pépinière ont montré que (i) le sol de pépinière non stérilisé contient des CMA (champignon mycorhizien à arbuscules) endogènes aussi infectifs que les souches contrôlées ; (ii) lapport du Glomus intraradices est efficace dans la stimulation de la production de biomasse totale et (iii) la mycorhization naturelle est quasi aussi efficace que les deux apports mycorhiziens dans la stimulation de la croissance en hauteur et dans la limitation de la perte deau des espèces par transpiration. Les résultats sur site confirment lefficacité comparable de la mycorhization naturelle et de celle des apports mycorhiziens. Bien que leffet du G. intraradices apparaisse être bénéfique en certains points chez quelques espèces, les effets observés ne justifient pas doffice de le préférer à linoculum composite de souches indigènes, ni à la mycorhization naturelle dans cette zone. -------------------------------------------------------------------------------- SUMMARY: The Southeastern of Niger Republic is subjected to the phenomenon of wind erosion. In Gouré, the oasis basins, which are the main source of agricultural productions and incomes, are threatened to disappear because of the sand silting up. Operations of sand dunes fixation are taken to save this productive capital. Assessment of the mechanical sand dunes fixation technique, used in this area, showed that this technique is effective in the ecological restoration of the environment. Three years after the implementation of the anti erosive fences, made of Leptadenia pyrotechnica branches, spontaneous floral vegetation, including 58 species (20 families) of which 17 perennials, had settled down inside the fences, owing 42 species more than in the untreated areas. Over the years, the floral composition gradually stabilized proving then a considerable reduction of the environmental disturbances caused by the erosive winds action. In a biological sand dunes fixation experiment, seven woody species, of which five natives (Acacia senegal, A. tortilis, A. nilotica, Bauhinia rufescens and Balanites aegyptiaca) and two exotic (Prosopis juliflora and P. chilensis) have been tested in that zone of the Southeastern of Niger Republic. In nursery, species underwent a water stress by interrupting the watering during six days. Foliar hydration has been determined in order to evaluate their capacity to limit water loss. In a field experiment, species have been planted on a mechanically prefixed sand dune cord in order to test their ability in sand dunes stabilization. Survival rates during the first three years have been calculated and height growth was measured. In nursery, results showed that, after six days of water stress, Acacia senegal, A. tortilis, P. chilensis and A. nilotica are the four species limiting the best the losses in water. Results on site showed that the best combination in sand dunes fixation, in this zone, would be the association of Prosopis chilensis specie (high survival rate and fast growth) with A. tortilis and/or A. nilotica (survival and growth relatively substantial and more important economic interest). In the optics of a further mycorrhizal inoculation essay, soil samples from Gouré department were collected beneath ten mature native and exotic tree species in order to identify the types of associated arbuscular mycorrhizal (AM) fungi and to produce an indigenous inoculum by growing three local trap cultures including millet, sorghum and cowpea. The results highlighted the presence of two families of Glomales in the soils including Glomaceae (belonging to the genus Glomus) and Gigasporaceae. With more than 56 % of spores, the genus Glomus is the most abundant of the identified Glomales and the most viable (55, 80 % of the live spores). The length growth of sorghum and cowpea plants was significantly stimulated by inoculation. The three trap cultures species are equivalent in the spores trapping. An indigenous mycorrhizal complex was produced from this spore culture. Effects of the natural mycorhization were compared with those of the addition of this indigenous mycorrhizal complex and Glomus intraradices. A natural unsterile culture substrate was inoculated with the indigenous inoculum or with G. Intraradices. Inoculation effects were assessed on five woody species, among which three Acacias species (A. nilotica, A. tortilis, A. senegal), Bauhinia rufescens and Prosopis chilensis, in a tree nursery and on a sand dune of Gouré. In the nursery, species underwent a water stress by interrupting the watering during six days. Foliar hydration has been determined in order to evaluate the respective effects of the mycorrhizal inoculation on the water loss limitation. Mycorrhizal root colonization has been determined as well as plant height and total biomass. In a field experiment, inoculated and non inoculated species have been planted on a mechanically prefixed sand dune portion in order to evaluate the effects of mycorrhizal inoculations on growth in the field. Results in nursery showed that (i) the non sterile soil would contain some endogenous AMF (arbuscular mycorrhizal fungi) as infectious as those in soils with mycorrhizal additions; (ii) addition of Glomus intraradices would be efficient to stimulate total biomass and (iii) natural mycorhization would be as efficient as both mycorrhizal addition in growth stimulation and water loss limitation by transpiration. Results on site confirm the comparable effectiveness of the natural mycorhization and mycorrhizal additions. Although the addition of G. intraradices appears to be slightly superior by some aspects on some species, the observed effects do not justify preferring it, when compared to indigenous composite inoculum or to natural mycorhization in this zone.
242

Human genetic factors involved in immunity to Plasmodium falciparum infection

Vafa Homann, Manijeh January 2008 (has links)
This study investigated the associations between IL-4 -590 C/T and IL-10 -1087 A/G polymorphisms and malariometric indexes in the Fulani and the Dogon ethnic groups living in sympatry in Mali and differing in susceptibility to malaria. The correlations between antibodies level and parasitological data as well as splenomegaly were assessed. The impact of IL-4 -590 variants on the levels of the studied antibodies was also studied. The allele and genotype frequencies of both studied SNPs differed significantly between the two groups. The Fulani IL-4 T allele carriers had a significantly higher infection prevalence compared with those carrying the CC genotype. No correlation between anti-malarial antibody levels and parasite prevalence was seen in any of the communities. In the Fulani, the increase in total IgE levels was related to the presence of infection. Malaria-specific IgG4 levels were negatively correlated to the number of clones within the Fulani. The Fulani IL-4 T allele carriers had higher total and malaria-specific IgE levels, compared to the CC genotype carriers. These results suggest that the amount of antibodies may not be the key element in the protection against malaria. IgG4 might be involved in protection against malaria. The impact of IL-4 -590 variants on the antibody levels may be affected by other genetic/epigenetic/epistatic or environmental factors. In the study in Senegal, multiplicity of infection (MOI) increased after the transmission season in all subjects, except in α-thalassaemic and in G6PD-mutated children, suggesting that α-thalassaemia may protect against infection by certain parasite strains. G6PD-mutated individuals may resist against increase in MOI after the transmission season due to rapid clearance of infection at an early stage. HbAs and the ABO system do not affect MOI in asymptomatic individuals. MOI was positively correlated to parasitemia, and did not vary over age (in the range of 2 to 10 years). No relation between MOI and clinical attack was noted.
243

Deconstructing ‘Community’ in Community-Based Natural Resource Management (CBNRM): Investigating Traditional Method of Subsistence (TMoS), Traditional Ecological Knowledge (TEK), and Ethnic Diversity for more effective resource management in the Kedougou Region of Senegal

Stirling, Peter Fraser 30 April 2012 (has links)
This thesis seeks to highlight the importance of a geographic and culturally specific knowledge base to guide natural resource management and governance policy, particularly within the West African context. In order to demonstrate the level of complexity that may exist within this realm, the Kedougou region of Senegal is used as a case study. Traditional Method of Subsistence (TMoS), Traditional Ecological Knowledge (TEK), and ethnic diversity are considered in order to validate the need to go beyond a superficial involvement of community within models such as Community-based Natural Resource Management (CBNRM). Focus groups were conducted for this case study in order to identify areas of similarity and difference that exist along ethnic lines. Two areas of concern that all ethnic groups agreed upon was a depletion of water resources and a diminished growing season that leads to an annual food shortage in the region. Three primary areas of difference were found to coincide with traditional ethnic boundaries in the region: traditional religious belief, wealth accumulation and social hierarchy. The findings of this research demonstrate that while areas of cohesive community concern may serve as a focal point for CBNRM programs, it is also important to consider areas of ethnic difference which hold the potential to significantly influence sustainable and equitable resource management. For example, while traction methods for intensified agriculture are identified as important by all ethnic groups represented in this thesis: (A) traditional agricultural ethnic groups already have experience with these methods, and may only need access to assistance such as micro-credit opportunities, (B) the pastoral ethnic groups already have an abundance of traction animals, and so equipment may be what is primarily needed, while (C) the horticultural group may not have access to the land necessary for optimal traction agriculture. It is therefore suggested that CBNRM programs must be structured around community variables found along cultural lines in order to be of value to government and non-government conservation programs and policy formation in the region.
244

Electrifying Development: Identifying Key Policy Tools For Facilitating Rural Electrification in Sub-Saharan Africa

Shimkus, Jacob 01 January 2015 (has links)
Rural electrification is a critical tool for accelerating and enhancing development throughout Sub-Saharan Africa. The challenge for modern policymakers is to identify and implement programs that will effectively facilitate rural electrification. This analysis develops a model for comparing the performance of nations' electrification policies using a fixed effects regression model based on World Bank data from 1990, 2000 and 2010. To identify the key policies for driving rural electrification, this analysis then compares the programs and reforms employed in six nations from Sub-Saharan Africa. As a result, three reform measures are identified that are conditional on outside factors for their contribution to success, and three universal policies are identified that may be broadly applied to improve rural electrification throughout the region.
245

Deconstructing ‘Community’ in Community-Based Natural Resource Management (CBNRM): Investigating Traditional Method of Subsistence (TMoS), Traditional Ecological Knowledge (TEK), and Ethnic Diversity for more effective resource management in the Kedougou Region of Senegal

Stirling, Peter Fraser 30 April 2012 (has links)
This thesis seeks to highlight the importance of a geographic and culturally specific knowledge base to guide natural resource management and governance policy, particularly within the West African context. In order to demonstrate the level of complexity that may exist within this realm, the Kedougou region of Senegal is used as a case study. Traditional Method of Subsistence (TMoS), Traditional Ecological Knowledge (TEK), and ethnic diversity are considered in order to validate the need to go beyond a superficial involvement of community within models such as Community-based Natural Resource Management (CBNRM). Focus groups were conducted for this case study in order to identify areas of similarity and difference that exist along ethnic lines. Two areas of concern that all ethnic groups agreed upon was a depletion of water resources and a diminished growing season that leads to an annual food shortage in the region. Three primary areas of difference were found to coincide with traditional ethnic boundaries in the region: traditional religious belief, wealth accumulation and social hierarchy. The findings of this research demonstrate that while areas of cohesive community concern may serve as a focal point for CBNRM programs, it is also important to consider areas of ethnic difference which hold the potential to significantly influence sustainable and equitable resource management. For example, while traction methods for intensified agriculture are identified as important by all ethnic groups represented in this thesis: (A) traditional agricultural ethnic groups already have experience with these methods, and may only need access to assistance such as micro-credit opportunities, (B) the pastoral ethnic groups already have an abundance of traction animals, and so equipment may be what is primarily needed, while (C) the horticultural group may not have access to the land necessary for optimal traction agriculture. It is therefore suggested that CBNRM programs must be structured around community variables found along cultural lines in order to be of value to government and non-government conservation programs and policy formation in the region.
246

Français et italien, langues de l'immigration sénégalaise à Brescia ( Italie) : enquête sociolinguistique / French and italian languages of the senegalese immigration in Brescia (Italy) : a sociolinguistic survey

Verrecchia, Elisa 18 April 2012 (has links)
La thèse présente une analyse sociolinguistique du rôle des langues français et italien dans le cadre migratoire, notamment auprès de la communauté sénégalaise immigrée à Brescia (Italie). Dans la première partie, le premier chapitre est dédié au Sénégal, qui est décrit dans ses traits historiques, culturels, ethniques et religieux, et dont on examine la situation linguistique et sociolinguistique actuelle par rapport aux langues française, wolof et d’autres langues locales. On y décrit également la diaspora sénégalaise en Europe et en Italie dans ses différentes étapes. Le deuxième chapitre se focalise sur Brescia, ville d’élection des migrants sénégalais en Italie, à cause de ses caractéristiques socioéconomiques qui la rendent un territoire particulièrement favorable à la création de réseaux de solidarité entre Sénégalais et autochtones. La deuxième partie est entièrement dédiée à l’analyse sociolinguistique des langues en jeu dans ce contexte, notamment le wolof ainsi que d’autres langues nationales du Sénégal, le français et l’italien. L’enquête se base sur vingt interviews faites à un échantillon de Sénégalais résidents à Brescia, desquelles émergent les pratiques et les représentations linguistiques des sujets par rapport aux langues connues et parlées. Pour amplifier l’éventail de l’enquête on a choisi d’inclure également un échantillon de Sénégalais immigrés à Milan, dont les réponses ont été insérées dans l’analyse générale des pratiques et des représentations linguistiques en question. Les conclusions de la thèse consistent dans un bilan d’ensemble de la recherche et dans une relecture de la méthode adoptée pour l’enquête. / This thesis presents a sociolinguistic analysis of the role of French and Italian language in the migration context, notably in the community of Senegalese immigrants in Brescia (Italy). In the first part, the first chapter is dedicated to Senegal, which is described in its historical, cultural, ethnic and religious features and depicted as far as its current linguistic and sociolinguistic situation is concerned, referring to French, Wolof and other local languages. The evolution of the Senegalese diaspora in Europe and Italy, in its different stages, is treated as well. The second chapter focuses on Brescia, elective hometown of the Senegalese in Italy, because of its socio-economic features which make it a territory particularly favorable to the creation of solidarity networks between Senegalese and Italian people. The second part is entirely dedicated to the sociolinguistic analysis of the languages involved in this context, notably Wolof, along with other national languages of Senegal, French and Italian. The survey is based on twenty interviews made with a sample of Senegalese immigrants in Brescia, from which the linguistic practices and representations of the subjects, about the languages known and spoken, emerge. To expand the scope of the survey, a sample of Senegalese immigrated in Milan has been included as well, and their interviews have been inserted in the general analysis of the linguistic practices and representations under focus. In the conclusions of the thesis, a global view on the research carried out and on the method adopted for the survey will be given.
247

Écologie et taxonomie intégrative des moucherons piqueurs du genre Culicoides Latreille (Diptera Ceratopogonidae) en région Afrotropicale. / Ecology and integrative taxonomy of biting midges of the genus Culicoides Latreille (Diptera Ceratopogonidae) in the Afrotropical region.

Bakhoum, Mame Thierno 05 September 2017 (has links)
Dans un contexte d’émergence ou de réémergence des maladies à transmission vectorielle, certaines espèces de Culicoides (Diptera : Ceratopogonidae) sont impliquées dans la transmission de certains virus (Reoviridae : Orbivirus) et de nématodes (Onchocercidae : Mansonella) en région Afrotropicale. Cependant, le schéma systématique et taxonomique ainsi que la bio-écologie des espèces d’intérêt vétérinaire restent à explorer. Ce travail de taxonomie intégrative a pour objectifs de réaliser (i) une révision systématique et taxonomique des espèces appartenant à des sous-genres et des groupes d’intérêt à partir de phylogénie moléculaire multi-marqueur et de délimitation d’espèces, et (ii) de développer des outils moléculaires pour l’étude de la bio-écologie des espèces d’intérêt vétérinaire et de la dynamique de leurs populations d’immatures. Nos résultats mettent en évidence (i) la présence de trois clades monophylétiques le groupe d’espèces Imicola, le groupe d’espèces Milnei et le sous-genre Remmia, (ii) une nouvelle espèce pour la science nommée C. sp. #22 et affiliée au sous-genre Avaritia, groupe Imicola, (iii) la présence d’une nouvelle espèce non-décrite nommée C. sp. #54 appartenant au groupe d’espèces Dasyops, sous-genre Avaritia, (iii) d’affilier les groupes d’espèces Similis et Neavei au sous-genre Synhelea et, (iv) de poser l’hypothèse d’une présence d’espèces cryptiques au sein de C. oxystoma (sous-genre Remmia). D’un point de vue bio-écologique, le travail réalisé combinant suivi entomologique et identification moléculaire avec une librairie de séquences barcodes a permis de décrire le comportement trophique de C. imicola, C. kingi et C. oxystoma ainsi que leurs habitats larvaires dans des environnements équins de la zone des Niayes au Sénégal. L’ensemble de ce travail permet de compléter le corpus de connaissances sur le genre Culicoides en région Afrotropicale afin d’améliorer la compréhension de l’épidémiologie des pathogènes transmis et proposer des pistes de recherches pour mieux contrôler les populations immatures et adultes des espèces vectrices afin de mieux anticiper et prévenir des évènements sanitaires. / In a context of emergence or re-emergence of vector-borne diseases, certain species of Culicoides (Diptera: Ceratopogonidae) are involved in the transmission of certain viruses (Reoviridae: Orbivirus) and nematodes (Onchocercidae: Mansonella) in the Afrotropical region. However, the systematic and taxonomic schemes as well as the bio-ecology of species of veterinary interest remain to be explored. This work of integrative taxonomy aims to achieve (i) a systematic and taxonomic revision of species belonging to subgenera and groups of veterinary interest using a multi-marker molecular phylogeny and species delineation, and (ii) to develop molecular tools for studying the bioecology of species of veterinary interest and dynamics of their immature populations. Our results show (i) the presence of three monophyletic clades, the Imicola group, the Milnei group and the subgenus Remmia, (ii) a new species for science named C. sp. # 22 and affiliated into the subgenus Avaritia, Imicola group, (iii) the presence of a new undescribed species named C. sp. # 54 belonging to the Dasyops group, subgenus Avaritia, (iii) affiliating the Similis and Neavei species groups to the subgenus Synhelea, and (iv) cryptic species within C. oxystoma (subgenus Remmia). From a bioecological point of view, this work combining entomological follow-up and molecular identification with a library of barcode sequences allowed to describe the trophic behavior of C. imicola, C. kingi and C. oxystoma as well as their larval habitats in equine environments of the Niayes area in Senegal. This work completes the corpus of knowledge about the genus Culicoides in the Afrotropical region to improve our knowledge on the epidemiology of the transmitted pathogens and to propose research tracks to better control the immature and adult populations of the vector species in order to better anticipate and prevent Culicoides-borne diseases outbreaks.
248

Le sud du Sénégal à l'heure de la culture irriguée de la banane : innovations agricoles et dynamiques territoriales / Southern Senegal at the time of irragated banana farming : agricultural innovations and territorial dynamics

Badji, Seydou 09 December 2017 (has links)
Cette thèse étudie les dynamiques territoriales induites par le développement de la culture irriguée de la banane dessert, dans le sud du Sénégal, dans un contexte de systèmes de production profondément pluviaux et de marginalisation des grandes dynamiques de développement nationales. En tant que culture intensive et marchande, cette innovation agricole pose la question de son adoption, mais surtout de sa rentabilité économique face à l'enclavement et de ses interactions avec les dynamiques locales de développement. Pour répondre à cette question, la thèse s'est appuyée sur des enquêtes qualitatives auprès de divers acteurs de la filière banane (producteurs, commerçants, encadreurs, intermédiaires, etc.) et d'une lecture attentive des mutations en cours au sud du Sénégal. La thèse s'organise ainsi autour de trois parties. La première montre que c'est dans le caractère marginal des régions sud du Sénégal que réside les facteurs naturels et socio­économiques d'émergence de la culture irriguée de la banane. La seconde partie analyse le processus de son intégration dans les stratégies productives des paysans en insistant sur l'organisation de la production et les dynamiques de sa commercialisation. La troisième partie interroge les effets socio-économiques et géographiques de la dynamique de développement de l'innovation bananière dans le sud du Sénégal, en la replaçant au centre des recompositions socio-économiques et environnementales en cours aux niveaux local et régional. Cette thèse est ainsi une contribution à l'étude des «opérations de développement» en milieu rural africain et des possibilités de développement des régions marginalisées en Afrique de l'ouest. / This thesis examines dessert banana cropping development induced territorial dynamics in the southern Senegal region, characterized by highly rained-dependent production systems and by a marginalization of the major national development dynamics. As an intensive and market-oriented crop, this agricultural innovation raises the question of its adoption in rain-fed systems, and above all its economic profitability in an isolation context and its interactions with local development dynamics. To answer this question, this thesis was based on data obtained from qualitative surveys of various banana sector stakeholders (producers, traders, supervisors, intermediaries, etc.) and a careful analysis of the ongoing changes in southern Senegal. The thesis is thus articulated on three axes. The first axis shows that the natural and socioeconomic factors that led to the event of irrigated banana cropping stems from the marginal nature of the southern regions of Senegal. The second part analyzes its integration process into farmers' the productive strategies while emphasizing on produces' organizations, banana production practices and marketing dynamics. Finally, an analysis of the socio-economic and geographical effects of banana cropping innovation dynamic development in southern Senegal, substituting banana innovation at the center of the ongoing socio-economic and environmental reorganizations bath at the local and regional levels. This thesis is thus a contribution to the study of "development operations" in rural Africa and the development opportunities of marginalized areas in West Africa.
249

Français Tirailleur : - A Corpus Study

Skirgård, Hedvig January 2013 (has links)
Français Tirailleur (FT) är ett pidginspråk som talades av västafrikanska soldateroch deras vita officerare i den franska kolonialarmen cirka 1857-1954. Den häruppsatser beskriver denna språkvatietet utifrån ett korpus som består av de dokumenteradeyttranden som hittills hittats. Studien visar bland annat att standardnegation uttrycks med en pre-verbal partikel (pas), ja/nej-frågor uttryckts främstgenom intonation, genussystemet är inte produktivt, det finns ingen skillnad mellansubjekt och objekt i pronomensystemet och attributiv ägande uttrycks med possessivapronomen, juxtaposition eller prepositioner. Den standardiserade type-token-rationär 26%, vidare forskning om ordförråd i pidginspråk och jämförelser med talat språkbehövs. Det finns två former som är väldigt frekventa och som anses vara mycketkarakteristiska för FT: ya och yena. Dessa former har tidigare beskrivits som stativaverb, relativmarkörer och finithetsmarkörer. De förekommer i majoriteten av alladokument i korpuset. De fungerar som stativa verb, kopula eller kopulalika markörer,samt potentiellt även som predikatsmarkörer. Frågan om huruvida adjektiv är enrelevant språklig kategori i denna pidgin diskuteras också i denna uppsats. / Français Tirailleur (FT) is a pidgin language that was spoken by West Africansoldiers and their white officers in the French colonial army approximately 1857-1954.The aim of this study is to investigate a corpus of previously unanalyzed utterancesof FT in order to discern linguistic structures and test previous statements about thenature of FT. Much of previous literature on FT is based on an anonymous manualpublished by the French military in 1916, this thesis aims to provide new informationto our understanding of this pidgin. These are some of the findings: standardnegation is expressed by means of a preverbal particle (pas), polar interrogation byintonation, grammatical gender is not a productive category and attributive possessionis expressed by possessive pronouns, juxtaposition (possessum - possessor) andprepositional constructions. The standardized type-token-ratio of this corpus, 26%,suggests that the lexicon of pidgins needs to be further studied. Comparisons withcorpuses of spoken language are needed. There are two very frequent pre-predicatemarkers that are considered characteristic of FT: ya and yena. These two markershave previously been described as stative verbs, relativizers and markers of finiteness.The two markers are very frequent in a majority of the sources and are highly polysemous,functioning as stative verbs, copula or copula-like markers and possibly alsopredicate markers. The status of adjectives as a part-of-speech in FT is also discussed.
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Répertoire des bactéries identifiées par Maldi-Tof en Afrique de l'Ouest / Repertory of bacteria identified in West Africa by Maldi-Tof

Lo, Cheikh Ibrahima 07 December 2015 (has links)
Le répertoire des bactéries est mal connu en Afrique du fait des méthodes d’étude essentiellement basées sur des techniques de culture sur milieux simples associées à des tests biochimiques, ce qui ne permet pas son exploration. Il a néanmoins été récemment bouleversé par l’usage systématique de la spectrométrie de masse de type MALDI-TOF MS.Au cours de nos travaux de thèse de doctorat, nous avons utilisé deux types de spectromètres de masse: le MALDI-TOF Vitek MS, nouvellement installé à Dakar; le MALDI-TOF Microflex LT, installé à Marseille. Les résultats que nous avons obtenus ont montré, pour la première fois, que la technique du MALDI-TOF est efficace et tout à fait adaptée en Afrique pour le diagnostic spécifique de routine. Cette performance a conduit le laboratoire clinique de l’HPD à opter pour son utilisation à la place des traditionnelles techniques d’identification phénotypique telles que les galeries API. Nous avons également confirmé que le MALDI-TOF est un puissant outil d’identification des espèces bactériennes rarement impliquées dans les maladies infectieuses humaines. De plus, cet outil nous a permis de détecter sept nouvelles espèces de bactéries isolées pour la première fois chez l’homme. En Afrique, il faudrait donc multiplier l’installation de spectromètre de masse MALDI-TOF, ou mettre en place des réseaux autour de plateformes MALDI-TOF sous-régionales partagées entre plusieurs structures sanitaires et/ou de recherche. / The Africa bacteria repertory is unfamiliar because the available tools in this region are not allowed its best knowledge. In fact, bacteria are most often identified using culture techniques on simple media and biochemical tests which enable the identification of some common characters. These methods do not facilitate an exhaustive knowledge of the bacterial repertory; consequently they have recently been revolutionized by the systematic use of MALDI-TOF mass spectrometry (MS).In our thesis we used two mass spectrometers, respectively, MALDI-TOF Vitek MS currently installed at Dakar (Senegal) and MALDI-TOF Microflex LT installed in Marseille (France). In addition we have also confirmed that MALDI-TOF is a powerful tool for identifying bacterial species rarely involved in human infectious diseases. Thus in adopting the MALDI-TOF as a first-line tool in bacterial identification before Gram staining or other techniques of phenotypic identifications based on chemical characteristics, we discovered seven new species of bacteria isolated for first time in humans. Microbial identification using MALDI-TOF MS is currently feasible in Africa. Its performance and effectiveness in routine diagnosis of clinical microbiology laboratories have been proven. It is necessary either to increase the installation of MALDI-TOF, or establishing a network around a shared MALDI-TOF platform between several structures located in the same area, especially in the underdeveloped countries of Africa amortization of investment costs of the device, because it allowed reducing the time of reporting results and indirectly facilitating better care for patients.

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