Edi C.V.A.,Center Suisse Of Recherches Scientifiques En Cote Divoire |
Koudou B.G.,University dAbobo Adjame
Emerging Infectious Diseases | Year: 2012
control depends on mosquito susceptibility to insecticides. We tested Anopheles gambiae mosquitoes from Côte d'Ivoire for resistance and screened a subset for target site mutations. Mosquitoes were resistant to insecticides of all approved classes. Such complete resistance, which includes exceptionally strong phenotypes, presents a major threat to malaria control.
Hassam S.,CNRS Institute Materials Microelectronics nanosciences of Provence |
Boa D.,University dAbobo Adjame |
Rogez J.,CNRS Institute Materials Microelectronics nanosciences of Provence
Journal of Alloys and Compounds | Year: 2012
The molar enthalpies of mixing of the Au-In, In-Sb and Au-In-Sb alloys have been determined at 973 K using a Calvet high-temperature microcalorimeter by the drop method. Measurements in the ternary system Au-In-Sb were performed along four sections, x Au/x In = 1/3-1/1 and x In/x Sb = 1/1-3/1. The experimental calorimetric data and estimated values with a Redlich-Kister-Muggianu formulation are compared. © 2011 Elsevier B.V. All rights reserved.
Kone W.M.,University dAbobo Adjame |
Vargas M.,Swiss Tropical and Public Health Institute |
Vargas M.,University of Basel |
Keiser J.,Swiss Tropical and Public Health Institute |
Keiser J.,University of Basel
Parasitology Research | Year: 2012
Natural products play an important role in the discovery and development of new pharmaceuticals. In the present study, we assessed the anthelmintic properties of medicinal plants used in Cote d'Ivoire. Ethanolic extracts from 50 medicinal plants were tested in vitro against trematodes (Echinostoma caproni, Schistosoma mansoni) and nematodes (Ancylostoma ceylanicum, Heligmosomoides bakeri, Trichuris muris). Active extracts were evaluated for their cytotoxicity and followed up in vivo in mice harbouring adult S. mansoni, E. caproni and T. muris at single oral doses of 400 or 800 mg/kg. All extracts tested were active against at least one helminths species. Ten of the 65 extracts tested (15.4%) in vitro revealed activity against all helminths tested. Of 65 extracts tested in vitro at a concentration of 2 mg/ml, all caused death of schistosomula and 34.4% and 39.1% were lethal against adult S. mansoni and E. caproni 72 h post-incubation, respectively. The highest activity against A. ceylanicum in vitro was observed with Sclerocarya birrea at 2 mg/ml, which resulted in death of adult worms and inhibition of activity of third-stage larvae (L3). Of the extracts, 41.5% completely inhibited movement of H. bakeri L3 at minimal lethal concentration (MLC) values of 20-200 μg/ml 48 h post-incubation, and 15.4% paralysed adult H. bakeri at 200 μg/ml 72 h after incubation. Of the extracts, 19% resulted in death of adult T. muris at MLC values of 10-100 μg/ml. In vivo, none of the extracts tested revealed activity against E. caproni. Olax subscorpioidea achieved total and female worm burden reductions of 60% and 84%, respectively in S. mansoniinfected mice. Combretum mucronatum was the most active extracts in vivo against T. muris with a worm burden reduction of 85.3%. In conclusion, several of the medicinal plants used in Côte d'Ivoire are active against different helminths, hence might play a role in the treatment of helminthiases. Further studies are necessary to isolate the active components from these extracts. © Springer-Verlag 2011.
Kone Y.J.M.,University of Liège |
Kone Y.J.M.,University dAbobo Adjame |
Abril G.,University of Bordeaux 1 |
Delille B.,University of Liège |
Borges A.V.,University of Liège
Biogeochemistry | Year: 2010
We report a data-set of dissolved methane (CH4) in three rivers (Comoé, Bia and Tanoé) and five lagoons (Grand-Lahou, Ebrié, Potou, Aby and Tendo) of Ivory Coast (West Africa), during the four main climatic seasons (high dry season, high rainy season, low dry season and low rainy season). The surface waters of the three rivers were over-saturated in CH4 with respect to atmospheric equilibrium (2221-38719%), and the seasonal variability of CH4 seemed to be largely controlled by dilution during the flooding period. The strong correlation of CH4 concentrations with the partial pressure of CO2 (pCO2) and dissolved silicate (DSi) confirm the dominance of a continental sources (from soils) for both CO2 and CH4 in these rivers. Diffusive air-water CH4 fluxes ranged between 25 and 1187 μmol m-2 day-1, and annual integrated values were 288 ± 107, 155 ± 38, and 241 ± 91 μmol m-2 day-1 in the Comoé, Bia and Tanoé rivers, respectively. In the five lagoons, surface waters were also over-saturated in CH4 (ranging from 1496 to 51843%). Diffusive air-water CH4 fluxes ranged between 20 and 2403 μmol m-2 day-1, and annual integrated values were 78 ± 34, 338 ± 217, 227 ± 79, 330 ± 153 and 326 ± 181 μmol m-2 day-1 in the Grand-Lahou, Ebrié, Potou, Aby and Tendo lagoons, respectively. The largest CH4 over-saturations were observed in the Tendo and Aby lagoons that are permanently stratified systems (unlike the other three lagoons), leading to anoxic bottom waters favorable for a large CH4 production. In addition, these two stratified lagoons showed low pCO2 values due to high primary production, which suggests an efficient transfer of organic matter across the pycnocline. As a result, the stratified Tendo and Aby lagoons were respectively, a low source of CO2 to the atmosphere and a sink of atmospheric CO2 while the other three well-mixed lagoons were strong sources of CO2 to the atmosphere but less over-saturated in CH4. © 2010 Springer Science+Business Media B.V.
Guei A.M.,University dAbobo Adjame |
Tondoh J.E.,University dAbobo Adjame
Ecological Indicators | Year: 2012
It is widely admitted that earthworms are potential indicators of soil quality. However, very little is known about the preference of species or assemblage of species for a range of ecosystems with respect to soil quality status. This study aimed to find indicator species and species assemblages of earthworms characterizing soil quality measured by soil organic matter (SOM), available P, bulk density (BD) and pH in semi-deciduous forest areas of Ivory Coast. Soil samples along with earthworms were sampled in three sites comprising each one various land-use types (e.g. forests, cocoa plantations, 2 and 5 year-old fallows and mixed-crop fields). Forest conversion into agroecosystems implies marked variations in soil organic carbon, total N, pH and BD, which in turn significantly induced changes in earthworm biomass, species richness and Shannon diversity index. At the end of this study, we came to the conclusion that earthworm species can be used to monitor the status of ecosystems as some species showed preferences to land-use types with different levels of soil quality: (i) Millsonia sp.; a geophageous species associated to forests or SOM-rich sites, (ii) Hyperiodrilus africanus, Dichogaster sp.3 and Millsonia omodeoi indicating mixed crop fields or SOM-poor sites, and (iii) Dichogaster eburnea, Dichogaster saliens, Dichogaster baeri, Dichogaster mamillata, Dichogaster terraenigrae, Sthulmannia zielae, and Scolecillus compositus linked to moderately disturbed systems (cocoa plantations and fallows). The contribution of this species or groups of species to monitor soil health is discussed. © 2012 Elsevier Ltd. All rights reserved.
Ekou T.,French National Center for Scientific Research |
Ekou T.,University dAbobo Adjame |
Especel C.,French National Center for Scientific Research |
Royer S.,French National Center for Scientific Research
Catalysis Today | Year: 2011
Pt/x%Ti-SBA15 catalysts (x corresponding to the wt.% TiO 2 loading in the Ti-SiO 2 composite, in the range 25-60%) were synthesized by titanium precursor grafting in preformed mesoporous silica. Materials were characterized by several techniques, including elemental analysis, XRD, TEM and N 2-sorption isotherms to achieve structural and textural properties description. Different pore sizes were obtained for the SBA-15 materials, by using or not hexane as swelling agent. The catalytic performances of these original materials were evaluated for the selective hydrogenation of citral (α,β-unsaturated aldehyde), and compared with those of Pt/SBA and Pt/TiO 2 P25 reference catalysts. Pt/x%Ti-SBA15 catalysts present high specific surface, with TiO 2 nanoparticles and Pt 0 clusters located inside the hexagonal mesopore structure of silica. During citral hydrogenation, the selectivity towards unsaturated alcohols (nerol and geraniol) varies as a function of the support nature as follows: Pt/x%Ti-SBA15 > Pt/TiO 2 P25 Pt/SBA. The results are discussed in term of variable metal-support interaction (SMSI) generated by the partial reduction of TiO 2 species, this SMSI effect being reported more important over anatase TiO 2 nanoparticles dispersed inside the mesostructure than over large crystals encountered in the classical P25 support. © 2011 Elsevier B.V. All rights reserved.
Nobre T.,Wageningen University |
Kone N.A.,Wageningen University |
Kone N.A.,University dAbobo Adjame |
Konate S.,University dAbobo Adjame |
And 2 more authors.
Molecular Ecology | Year: 2011
The mutualistic symbiosis between fungus-growing termites and Termitomyces fungi originated in Africa and shows a moderate degree of interaction specificity. Here we estimate the age of the mutualism and test the hypothesis that the major splits have occurred simultaneously in the host and in the symbiont. We present a scenario where fungus-growing termites originated in the African rainforest just before the expansion of the savanna, about 31 Ma (19-49 Ma). Whereas rough age correspondence is observed for the four main clades of host and symbiont, the analysis reveals several recent events of host switching followed by dispersal of the symbiont throughout large areas and throughout different host genera. The most spectacular of these is a group of closely related fungi (the maximum age of which is estimated to be 2.4 Ma), shared between the divergent genera Microtermes, Ancistrotermes, Acanthotermes and Synacanthotermes (which diverged at least 16.7 Ma), and found throughout the African continent and on Madagascar. The lack of geographical differentiation of fungal symbionts shows that continuous exchange has occurred between regions and across host species. © 2011 Blackwell Publishing Ltd.
Agency: European Commission | Branch: FP7 | Program: CSA-CA | Phase: ENV.2009.3.1.3.1 | Award Amount: 1.25M | Year: 2010
Most of African countries are struggling towards development and improving their living conditions. An appropriate waste management structure at a national and regional level is a milestone that must be achieved in order to improve living standards, health and environment. The situation in many countries is that the obvious lack of a functional waste management system brings perennial garbage problems such as inefficient garbage collection, poor public compliance to waste segregation, uncontrolled open burning, and tolerated presence of open dumpsites. Furthermore valuable resources are lost due to inefficient or non-existing recycling systems. The establishment of an efficient waste management and recycling system contributes to enhancing the resource efficiency of these countries and thus supports a sustainable development in the long-term. The present Coordination Action will seek the establishment of Integrated Solid Waste Management systems (ISWM) in Western Africa. ISWM systems combine waste streams, waste collection, treatment and disposal methods, with the objective of achieving environmental benefits, economic optimization and societal acceptability. For the achievement of the project objectives, a solid waste management expert and research co-ordination platform will analyze the current situation in the targeted countries (Ghana, Nigeria, Senegal and Ivory Coast), identifying main gaps and constraints of any type (technological, sociological, organisational, etc.) and selecting suitable management systems. According to the results obtained, including inputs from authorities and policy makers in participatory workshops, the consortium will provide valuable guidelines and recommendations to be used in the future implementation of developed strategies such as National and Regional Action Plans on solid waste management. The project will also build local capacities through workshops and seminars where relevant stakeholders must be involved.
Agency: European Commission | Branch: H2020 | Program: CSA | Phase: WASTE-4b-2014 | Award Amount: 1.64M | Year: 2015
Urbanization is on the rise in Africa and this trend is expected to continue in the future. The fast growing use of technology is creating a rising e-waste stream, for which there is limited recycling capacity. Waste management infrastructures and public awareness of the health issues is largely non-existent. Basic environmental precautions are almost absent and health and safety regulations are loosely enforced. Improvements are therefore urgently needed to combat related health issues, alleviate poverty and develop the local recycling sector. EWIT projects aim is to address these challenges, assisting African municipalities in the implementation of effective e-waste management systems for their communities. The project will develop a comprehensive mapping of the baseline data of African metropolitan areas related to e-waste management, analyzing the most relevant experiences, processes and legal tools available. It will then deliver a dynamic and easy to use information and service portal to offer guidance and practical support for the design and development of e-waste collection and recycling systems. EWIT will generate the expected impacts through 5 coordinated work packages. The working model is based on two different set of workshops, one led by Cities and the other by Experts. Tools, implementation models, policies and procedures will feed a dedicated information and service platform called E-waste implementation toolkit. This dynamic and easy to use internet portal will be a strategic source of knowledge for decision makers at industry and local government level. Dissemination will play a key role to assure that the projects deliverables are well understood and ready to be applied. EWIT will define the conditions and actions necessary to implement effective waste recycling systems in metropolitan areas, increasing recycling opportunities for entrepreneurs, generating new jobs and improving environment and health protection of local communities.
Kone W.M.,University dAbobo Adjame
African journal of traditional, complementary, and alternative medicines : AJTCAM / African Networks on Ethnomedicines | Year: 2012
Medicinal plants have been a source of succour in the control of many diseases in developing countries and anaemia is no exception. In this study, ethnomedical survey was carried out for recording medicinal plants used in Northern and South-Eastern Côte d'Ivoire against anaemia. Also iron content was determined for some of the recorded plants using phenanthroline method. Thirty (30) medicinal plants, covering 28 genera and 22 families were recorded. These plants were used to prepare 30 receipts for the treatment of anaemia and aggravating factors such as malaria and gastro-intestinal helminthes. Eleven (11) of these medicinal plants showed presence of iron in various quantities. The most promising were Tectona grandis, Amaranthus spinosus and Stylosanthes erecta which contained the highest iron contents viz; 266.6, 236.6 and 206.6 mg/100 g respectively. They were followed by Hoslundia opposita, Imperata cylindrica, Cajanus cajan, Thalia geniculata and Milicia excelsa. These results lend credence to the traditional use of these plants in Cote d'Ivoire's ethnomedicine for the treatment of anaemia.