Culture areas of Nigeria, by Wilfrid D. Hambly -- Frederick H. Rawson-Field Museum Ethnological Expedition to West Africa, 1929-30. 68 plates in photogravure and 1 map.

v.21:no.3(1935)

Review on the Molecular Tools for the Understanding of the Epidemiology of Animal Trypanosomosis in West Africa

The epidemiology of animal trypanosomosis around Bobo-Dioulasso (Burkina Faso, West Africa) benefited a lot in the last years from the progress of molecular tools. The two most used molecular techniques were the polymerase chain reaction for the diagnosis of the disease in cattle and the characterization of the trypanosomes in the host and the vector on one hand, and the microsatellite DNA polymorphism in tsetse flies to study the intraspecific genetic variability of the vector on the other hand. The results obtained in the Sideradougou area during a recent two year survey with these techniques, associated with many other georeferenced informations concerning vector and cattle distribution, natural environment, landuse, ground occupation, livestock management, were combined in a Geographical Information System. This new approach of a complex pathogenic system led to a better evaluation of the risk of trypanosome transmission.

Mosquito fauna on the Cape Verde Islands (West Africa): an update on species distribution and a new finding

To evaluate the risk of transmission of vector-borne diseases, regular updates of the geographic distribution of insect vectors are required. In the archipelago of Cape Verde, nine mosquito species have been reported. Of these, four are major vectors of diseases that have been present in the archipelago: yellow fever, lymphatic filariasis, malaria and, currently, an outbreak of dengue. In order to assess variation in mosquito biodiversity, we have carried out an update on the distribution of the mosquito species in Cape Verde, based on an enquiry of 26 unpublished technical reports (1983-2006) and on the results of an entomological survey carried out in 2007. Overall, there seems to be a general trend for an expansion of biological diversity in the islands. Mosquito species richness was negatively correlated with the distance of the islands from the mainland but not with the size of the islands. Human- and/or sporadic climatic-mediated events of dispersal may have contributed to a homogenization of species richness regardless of island size but other ecological factors may also have affected the mosquito biogeography in the archipelago. An additional species, Culex perexiguus, was collected for the first time in the archipelago during the 2007 survey.

Tornabenea ribeirensis (Apiaceaeb a new species from São Nicolau, Cape Verde Islands (West Africa)

Many species of Apiaceae are found in the Macaronesien Region. Several have been introduccd by human activities, but a number of taxa is endemic to the different archipelagos or even rrstrictcd to a single island. The following enumeration is based mainly on HANSEN & SUNDING ( 1993). In the Arores 28 different taxa of Apiaceae occur; among them four endemic species [AUIMI; hrrrrii WATSON, A. trifoliatum (WATSON) TKEL., Clrtrc~,y~l~~ll~r~~~ cl:oricrm TREL.. SOErich trwrictr GUTIINICK ex SEUB.]. In Madeira the Apiaceae are very diverse and consist ol’ 29 species and subspecies. From the archipelago two monotypic genera, rC/c/trtio. velitru~rr t/ccipicvr.s (SCHRAD. & J. C. WENDL.) Ho~+hl. md kJorli:ia edu[is LOWE and ~hrcc cndcmic species [Oemmrlre diwricore (R. BR.) MABB.. I/nperrr/orio lotvei COSS. and Burrirr~r hre~$~lirrnr LOWE] are described. The Canary Islands have the highest numbcr of plant-species and a high level of endemism. 5-l taxa of Apiaceae are recorded including three endemic genera (Rtrrheopsis A. HANSEX & KUNKEL, Todm-oa PARL. and Tiqyrmm PARL.) and further I5 endemic taxa. The Apiaceae are represented in the Cape Verde Islands by I2 species. Most of the taxa have been introduced by human activities (LOBIN & ZIZKA 1957) like Amvhm grm’eo- 1efr.s L., Apirm grmvolerrs L, Foerricrrhrr urlgore MILL.. Corimrtlru~t~ srrtirvrrrr L. or Petrosilerrm crisprrm (FRILL.) A.W.HILL. These species are cultivated and some of them later became \\esdy. Other species like Ciclosper- UWL /e/~fo/~/l~ll~rrtr (PER%) SPRAGUE (= Apimr leproplr~llrr~rr) are weeds of cultivated grounds or wasted lands. All these species are today widespread in temperate. subtropical or tropical regions all over the world. The only native species are to be found in the endemic genus To~wI~~I~~~ PARL.

Farmer-Managed Natural Regeneration Enhances Rural Livelihoods in Dryland West Africa

Declining agricultural productivity, land clearance and climate change are compounding the vulnerability of already marginal rural populations in West Africa. 'Farmer-Managed Natural Regeneration' (FMNR) is an approach to arable land restoration and reforestation that seeks to reconcile sustained food production, conservation of soils and protection of biodiversity. It involves selecting and protecting the most vigorous stems regrowing from live stumps of felled trees, pruning off all other stems, and pollarding the chosen stems to grow into straight trunks. Despite widespread enthusiasm and application of FMNR by environmental management and development projects, to date, no research has provided a measure of the aggregate livelihood impact of community adoption of FMNR. This paper places FMNR in the context of other agroforestry initiatives, then seeks to quantify the value of livelihood outcomes of FMNR. We review published and unpublished evidence about the impacts of FMNR, and present a new case study that addresses gaps in the evidence base. The case study focuses on a FMNR project in the district of Talensi in the semi-arid Upper East Region in Ghana. The case study employs a Social Return on Investment (SROI) analysis, which identifies proxy financial values for non-economic as well as economic benefits. The results demonstrate income and agricultural benefits, but also show that asset creation, increased consumption of wild resources, health improvements and psycho-social benefits created more value in FMNR-adopting households during the period of the study than increases in income and agricultural yields.

A new climatic periodisation of the Gold and Guinea Coasts in West Africa, 1750-1798 : a reconstruction of the climate during the slave trade era, including an analysis of the climatically facilitated Trans-Atlantic slave trade

Avsikten med studien är att producera den första rekonstruktionen av det västafrikanska klimatet mellan 1750 och 1798. Kunskapen om det västafrikanska klimatet före 1800-talet är till dags dato bristfällig, vilket gör det svårare att förstå framtida klimatvariationer. Det är bristen på instrumentell meteorologisk data (temperatur, regnmängd, och lufttryck), vilket i princip bara täcker det senaste århundradet, som är orsaken till att tidigare klimat är bristfälligt kartlagda. Klimatet och miljön är även sådana att proxydata från ’naturens arkiv’ (såsom t.ex. trädringar) har begränsad användning. Således är historiska dokument, främst från gästande kulturer/nationer/intressenter, innehållande deskriptiv information om vädret och klimatet, klimatforskarens viktigaste källa. Genom att använda tidigare, för det här syftet, oanvända källor påvisade den här undersökningen att klimatet i västra Afrika och Guldkusten (Ghana) har ändrats sedan 1700-talet. Monsunregnen var svagare och kortvarigare, speciellt den sekundära regnperioden under hösten var betydligt svagare än idag. Det förekom kraftiga årliga variationer i monsunregnen, men sett ur längre tidsperspektiv utmärktes torrare och blötare perioder. Studien kunde också visa en viss korrelation mellan det globala väderfenomenet El Niño och regnperiodens intensitet längs med kusten. Flera torrperioder sammanföll med tidigare registrerade El Niño sekvenser. Speciellt slutet av 1760-talet påverkades kraftigt av El Niño och även det globala klimatet verkar ha genomgått graftiga förändringar just dessa år. På basis av den nya klimatrekonstruktionen genomfördes också en jämförelse av klimatets inverkan på den transatlantiska slavhandeln från 1750 till 1798, en fråga som historikerna gjort anspelningar på i över 30 år. Utförseln av slavar från västra Afrika var som kraftigast under 1700-talets andra hälft. Analysen visade att slavhandeln delvis tilltog i samband med klimatanomalierna.

Pas-kaarte van de zuyd-west-kust van Africa : van Cabo Negro tot beoosten Cabo de Bona Esperanca

Julkaisussa: L'Atlas de la mer, ou monde aquaticque

Pas-kaarte van de zuyd-west-kust van Africa : van Cabo Negro tot beoosten Cabo de Bona Esperanca

Julkaisussa: L'Atlas de la mer, ou monde aquaticque

Genomic architecture of sickle cell disease clinical variation in children from West Africa : a case-control study design

Contexte : L’anémie falciforme ou drépanocytose est un problème de santé important, particulièrement pour les patients d’origine africaine. La variation phénotypique de l’anémie falciforme est problématique pour le suivi et le traitement des patients. L’architecture génomique responsable de cette variabilité est peu connue. Principe : Mieux saisir la contribution génétique de la variation clinique de cette maladie facilitera l’identification des patients à risque de développer des phénotypes sévères, ainsi que l’adaptation des soins. Objectifs : L’objectif général de cette thèse est de combler les lacunes relatives aux connaissances sur l’épidémiologie génomique de l’anémie falciforme à l’aide d’une cohorte issue au Bénin. Les objectifs spécifiques sont les suivants : 1) caractériser les profils d’expressions génomiques associés à la sévérité de l’anémie falciforme ; 2) identifier des biomarqueurs de la sévérité de l’anémie falciforme ; 3) identifier la régulation génétique des variations transcriptionelles ; 4) identifier des interactions statistiques entre le génotype et le niveau de sévérité associé à l’expression ; 5) identifier des cibles de médicaments pour améliorer l’état des patients atteints d’anémie falciforme. Méthode : Une étude cas-témoins de 250 patients et 61 frères et soeurs non-atteints a été menée au Centre de Prise en charge Médical Intégré du Nourrisson et de la Femme Enceinte atteints de Drépanocytose, au Bénin entre février et décembre 2010. Résultats : Notre analyse a montré que des profils d’expressions sont associés avec la sévérité de l’anémie falciforme. Ces profils sont enrichis de génes des voies biologiques qui contribuent à la progression de la maladie : l’activation plaquettaire, les lymphocytes B, le stress, l’inflammation et la prolifération cellulaire. Des biomarqueurs transcriptionnels ont permis de distinguer les patients ayant des niveaux de sévérité clinique différents. La régulation génétique de la variation de l’expression des gènes a été démontrée et des interactions ont été identifiées. Sur la base de ces résultats génétiques, des cibles de médicaments sont proposées. Conclusion: Ce travail de thèse permet de mieux comprendre l’impact de la génomique sur la sévérité de l’anémie falciforme et ouvre des perspectives de développement de traitements ciblés pour améliorer les soins offerts aux patients.

Root-induced increases in soil pH and nutrient availability to field-grown cereals and legumes on acid sandy soils of Sudano-Sahelian West Africa

A field experiment with millet (Pennisetum glaucum L.), sorghum [Sorghum bicolor (L.) Moench], cowpea (Vigna unguiculata L.) and groundnut (Arachnis hypogeae L.) was conducted on severely P-deficient acid sandy soils of Niger, Mali and Burkina Faso to measure changes in pH and nutrient availability as affected by distance from the root surface and by mineral fertiliser application. Treatments included three rates of phosphorus (P) and four levels of nitrogen (N) application. Bulk, rhizosphere and rhizoplane soils were sampled at 35, 45 and 75 DAS in 1997 and at 55 and 65 DAS in 1998. Regardless of the cropping system and level of mineral fertiliser applied, soil pH consistently increased between 0.7 and two units from the bulk soil to the rhizoplane of millet. Similar pH gradients were observed in cowpea, but pH changes were much smaller in sorghum with a difference of only 0.3 units. Shifts in pH led to large increases in nutrient availability close to the roots. Compared with the bulk soil, available P in the rhizoplane was between 190 and 270% higher for P-Bray and between 360 and 600% higher for P-water. Exchangeable calcium (Ca) and magnesium (Mg) levels were also higher in the millet rhizoplane than in the bulk soil, whereas exchangeable aluminium (Al) levels decreased with increasing pH close to the root surface. The results suggest an important role of root-induced pH increases for crops to cope with acidity-induced nutrient deficiency and Al stress of soils in the Sudano-Sahelian zone of West Africa.