Mve-Ondo B.,Center International Of Recherches Medicales Of Franceville Cirmf |
Mve-Ondo B.,British Petroleum |
Nkoghe D.,Center International Of Recherches Medicales Of Franceville Cirmf |
Nkoghe D.,British Petroleum |
And 19 more authors.
Malaria Journal | Year: 2015
Background: There have been many reports on the population genetic structure of Plasmodium falciparum from different endemic regions especially sub-Saharan Africa. However, few studies have been performed on neglected populations, such as the Pygmy populations. In this study, the population genetic structure of P. falciparum was investigated in the Baka Pygmies of Gabon and compared to that observed in neighboring villages composed mostly of Bantu farmers. Methods: A total of 342 blood samples were collected from 170 Baka Pygmies and 172 Bantus in the north of Gabon (Woleu Ntem Province). Plasmodium infections were characterized by sequencing a portion of the parasite cytochrome b gene. Population genetic structure of P. falciparum in the different villages was analysed using microsatellite markers and genes coding for antigenic proteins (MSP1, MSP2, GLURP, and EBA-175). Results: Overall, prevalence of P. falciparum was around 57 % and no significant difference of prevalence was observed between Pygmies and Bantus. No significant differences of population genetic structure of P. falciparum was found between Pygmy and Bantu people except for one antigen-coding gene, glurp, for which genetic data suggested the existence of a potentially disruptive selection acting on this gene in the two types of populations. The genetic structure of P. falciparum followed a pattern of isolation by distance at the scale of the study. Conclusion: The prevalence and genetic diversity of P. falciparum observed in Baka demonstrates a significant transmission of the parasite in this population, and some exchanges of parasites with Bantu neighbours. Despite that, some antigen-coding genes seem to have had a particular evolutionary trajectory in certain Pygmy populations due to specific local human and/or mosquito characteristics. © 2015 Mvé-Ondo et al. Source
Muspratt A.M.,Waste Enterprisers Ltd |
Nakato T.,Makerere University |
Niwagaba C.,Makerere University |
Dione H.,University Cheikh Antadiop Of Dakar |
And 5 more authors.
Journal of Water Sanitation and Hygiene for Development | Year: 2014
This research tested the viability of using faecal sludge (FS) as solid fuel - an end use that could unlock an environmentally and financially beneficial replacement for disposal-oriented FS management, while replacing fossil energy. FS samples were collected from pit latrines, septic tanks, drying beds and stabilization ponds in three cities, Kumasi, Dakar and Kampala. For each sample, the average calorific value, solids and water content, and their variation with source and age were determined. The average calorific value of untreated FS across the three cities was 17.3 MJ/kg total solids (TS), which compares well with other biomass fuels. The age of FS did not affect its calorific value, nor did the reduction in chemical oxygen demand (COD) that occurred while it was in drying beds. The TS content of FS depended on its source but ranged from 1 to 6% for sludge from septic tanks and pit latrines, respectively. Harnessing net energy from FS requires partial drying. The results indicate that sufficient drying occurs within two weeks in open-air drying beds, or in a matter of days with simple drying bed innovations. Source
Faye I.G.,University Cheikh Antadiop Of Dakar |
Diallo S.,University Cheikh Antadiop Of Dakar |
Tall M.S.,University Cheikh Antadiop Of Dakar |
Diedhiou I.,University Cheikh Antadiop Of Dakar |
And 2 more authors.
Physica Scripta | Year: 2011
The influence of an electric microfield distribution function (EMDF) on line shapes and on Stark broadening parameters is studied. For this purpose, we use different EMDFs obtained by theoretical calculations and computer simulation methods to calculate the allowed 4471 neutral helium line and its forbidden 4470 component. Correlation effects are shown by considering different categories of plasmas, weakly coupled plasmas and strongly coupled plasmas, with large gaps of temperature and density. © 2011 The Royal Swedish Academy of Sciences. Source
Ould El Moujtaba M.A.,University Cheikh Antadiop Of Dakar |
Ndiaye M.,University Cheikh Antadiop Of Dakar |
Diao A.,University Cheikh Antadiop Of Dakar |
Thiame M.,University Cheikh Antadiop Of Dakar |
And 2 more authors.
Research Journal of Applied Sciences, Engineering and Technology | Year: 2012
This study aims to demonstrate the effects of particles irradiation on the silicon solar cell properties. A theoretical study of a silicon solar cell under multispectral illumination and particles (electrons, protons...) irradiationis presented. The relative density is presented and we show that the space charge region width depend on the irradiation parameters (energy and nature especially). We also pointed out the influence of the irradiation on the following parameters: the photocurrent density, the open circuit voltage, the fill factor, the conversion efficiency, the shunt and series resistances and the diffusion capacitance of the solar cell. © Maxwell Scientific Organization, 2012. Source