LONG-RUN STRIGA CONTROL BY SUBSISTENCE FARMERS IN MALI

A dynamic programming model is developed to identify barriers to the adoption of long-run control programs for the parasitic weed Striga. The model is applied to Sirakorola in northwestern Mali. The ability of national and village-level institutions to overcome the barriers to adoption is explored.Community/Rural/Urban Development, Research and Development/Tech Change/Emerging Technologies,

Genetic Diversity of Selected Upland Rice Genotypes (Oryza sativa L.) for Grain Yield and Related Traits

Seventy-seven upland rice genotypes including popular cultivars in Nigeria and introduced varieties selected from across rice-growing regions of the world were evaluated under optimal upland ecology. These genotypes were characterised for 10 traits and the quantitative data subjected to Pearson correlation matrix, Principal Component Analysis and cluster analysis to determine the level of diversity and degree of association existing between grain yield and its related component traits. Yield and most related component traits exhibited higher PCV compared to growth parameters. Yield had the highest PCV (41.72%) while all other parameters had low to moderate GCV. Genetic Advance (GA) ranged from 9.88% for plant height at maturity to 41.08% for yield. High heritability estimates were recorded for 1000 grain weight (88.71%), days to 50% flowering (86.67%) and days to 85% maturity (71.98%). Furthermore, grain yield showed significant positive correlation with days to 50% flowering and number of panicles m-2. Three cluster groups were obtained based on the UPGMA and the first three principal components explained about 64.55% of the total variation among the 10 characters. The PCA results suggests that characters such as grain yield, days to flowering, leaf area and plant height at maturity were the principal discriminatory traits for this rice germplasm indicating that selection in favour of these traits might be effective in this population and environment

Gestion des forlts inondées dans le Delta Interieur du Niger, Mali; management of flood forests in the Inner Niger Delta, Mali

Flood forests of Acacia kirkii in the Inner Niger Delta, Mali, host large mixed colonies of waterbirds and play a key role in the production of fish fry and the fertilization of surrounding fields. These forests were managed in a sustainable way by local people, until many were destroyed during the drought periods in the 1970s and 1980s. Local populations wish to regenerate these forests, but without outside assistance they fail to do so, due to conflicts of interest

Utilisation de la PCR-RFLP sur de l'ADN chloro-plastique pour l'étude des relations phylogénétiques au sein du genre Phaseolus

Phylogenetic relationships among 74 accessions belonging to six species of Phaseolus are investigated using variation in chloroplast DNA assessed according to a PCR-RFLP protocol. Three fragments of chloroplast DNA are amplified using universal primers, and then digested with 10 restriction enzymes. Thirty-six haplotypes are identified on the basis of the polymorphism in fragment number and size. Three main phylogenetic groups, strongly supported through bootstrap analysis, are identified: (1) accessions from Phaseolus lunatus and Phaseolus xolocotzii; (2) accessions from Phaseolus glabellus; (3) accessions from Phaseolus vulgaris, Phaseolus polyanthus and Phaseolus coccineus. Within the third group, accessions of Phaseolus coccineus are scattered along the phylogenetic tree, which provides some evidence that coccineus accessions are paraphyletic with respect to Phaseolus vulgaris and Phaseolus polyanthus. An analysis of molecular variance applied on four species show that they are significantly differentiated with 79% of molecular variance among species and 21% within species. The results agree with previous investigations on chloroplast DNA variation in the genus Phaseolus, and suggest that PCRRFLP methods, which are technically less labour-intensive than previous methods, are of great value for phylogenetic investigations at the generic level

Synthesis of Perfectly Oriented MAPb0.93Cr0.07Br3 Perovskite Crystals for Thin-Film Photovoltaic Applications

[EN] Wide band gap methylammonium lead halide perovskites (CH3NH3PbX3, X=halogen; CH3NH3: MA) are interesting materials for photovoltaic applications. They have recently gained substantial attention because of their high efficiency, low cost, superior optical properties. The most attractive and representative perovskites are methylammonium lead halides (CH3NH3PbX3,) denoted as MAPbX3, X = Br, Cl, I. usually the optical and structural properties of CH3NH3PbBr3 can be adjusted by introducing other extrinsic ions such as chloride and bromide. In this work, instead of replacing the halogens I or Cl with bromine (Br) as usual, we preferred to act on the post-transition metal (Pb). To this end, we replaced lead with chromium (Cr) which is a transition metal and may have the same oxidation state (+2) as lead. MAPb0.93Cr0.07Br3 thin films were deposited on ITO substrate by the spin coating process. X-ray diffraction analyses indicated the formation of a cubic perovskite with space group Pm3 m. The structural analysis reveals films with (110) and (220) as main peaks. Deposited films showed a strong absorbance in the UV¿vis range. The band gap values were estimated from absorbance measurements. It was found between 1.60 and 1.80 eV. SEM analysis shows a morphology with good coverage and no apparent crystal orientation.Soro, D.; Sidibé, M.; Fassinou, W.; Marí, B.; Sall, T.; Fofana, B.; Boko, A.... (2017). Synthesis of Perfectly Oriented MAPb0.93Cr0.07Br3 Perovskite Crystals for Thin-Film Photovoltaic Applications. International Journal of Innovative Research in Science, Engineering and Technology. IJIRSET (Online). 6(6):10170-10176. doi:10.15680/IJIRSET.2017.0606007S10170101766

Hepatitis C virus cell-cell transmission and resistance to direct-acting antiviral agents

Hepatitis C virus (HCV) is transmitted between hepatocytes via classical cell entry but also uses direct cell-cell transfer to infect neighboring hepatocytes. Viral cell-cell transmission has been shown to play an important role in viral persistence allowing evasion from neutralizing antibodies. In contrast, the role of HCV cell-cell transmission for antiviral resistance is unknown. Aiming to address this question we investigated the phenotype of HCV strains exhibiting resistance to direct-acting antivirals (DAAs) in state-of-the-art model systems for cell-cell transmission and spread. Using HCV genotype 2 as a model virus, we show that cell-cell transmission is the main route of viral spread of DAA-resistant HCV. Cell-cell transmission of DAA-resistant viruses results in viral persistence and thus hampers viral eradication. We also show that blocking cell-cell transmission using host-targeting entry inhibitors (HTEIs) was highly effective in inhibiting viral dissemination of resistant genotype 2 viruses. Combining HTEIs with DAAs prevented antiviral resistance and led to rapid elimination of the virus in cell culture model. In conclusion, our work provides evidence that cell-cell transmission plays an important role in dissemination and maintenance of resistant variants in cell culture models. Blocking virus cell-cell transmission prevents emergence of drug resistance in persistent viral infection including resistance to HCV DAAs

L’apport de l’imagerie dans le diagnostic de la tuberculose uro-génitale (TUG): Une analyse de 4 observations et revue de la littérature

La tuberculose uro-génitale (TUG) est une localisation secondaire de la maladie. Son diagnostic est bactériologique, mais la probabilité de mettre en évidence le bacille de Koch (BK) dans les urines est faible. D’où le concours de l’imagerie dans le diagnostic et la mise en route du traitement médical. Nous rapportons 4 observations de patients atteints de TUG, dont les images radiologiques associées aux contextes clinique et épidémiologique ont fait évoquer une tuberculose urinaire et génitale. Dans un cas seulement l’uroculture s’est révélée positive au BK. Chez les trois autres patients où la culture urinaire a été négative, les résultats anatomopathologiques des pièces opératoires ont été en faveur d’une lésion tuberculeuse. D’où l’intérêt de la radiologie dans le diagnostic précoce et la prise en charge de la TUG.Mots clés : Tuberculose uro-génitale, bacille de Koch, imageri