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In urban Sub-Saharan Africa, the collection and transport of faecal sludge (FS) typically ends up with FS directly dumped into the urban environment, as safe treatment and disposal options are too expensive or non-existent. Resource recovery from FS treatment, such as dried FS as an industrial fuel, could provide a financial incentive to increase access to FS management services. In Dakar, Senegal, enhanced drying to reduce the footprint of drying beds for fuel production was evaluated.Greenhouses did not increase drying rates over uncovered beds, however, daily mixing of FS on the surface of the beds resulted in a 6 day reduction to achieve 90% total solids (TS). FS was dried to 90%

Isoniazid (INH), recommended by WHO (World Health Organization) in the treatment of tuberculosis (TB), is metabolized primarily by the genetically polymorphic N-acetyltransferase 2 (NAT2) enzyme. The human population is divided into three different phenotypic groups according to acetylation rate: slow, intermediate, and fast acetylators. The objective of this study was to explore the relationship between NAT2 genotypes and the serum concentrations of INH. Blood samples from 96 patients with TB were taken for the analysis. NAT2 polymorphisms on coding region were examined by polymerase chain reaction (PCR) direct sequencing; the acetylation status was obtained by measuring isoniazid (INH) and its metabolite, acetylisoniazid (AcINH) in plasma was obtained by using the liquid chromatography coupled to mass spectrometry. TB patients were distributed into two groups of fast and slow acetylators according to the acetylation index calculated based on the plasma concentration of INH in the 3rd hour (T3) after an oral dose. Our PCR analysis identified several alleles, where NAT2*4, NAT2*5A, NAT2*6A, and NAT2*13A were the most important. The concentrations of INH varied between 1.10 mg/L and 13.10 mg/L at the 3rd hour and between 0.1 and 9.5 mg/L at the 6th hour. The use of the acetylating index I3 allowed the classification of tested patients into two phenotypic groups: slow acetylators (44.3% of TB patients), and rapid acetylators (55.7%). Patient’s acetylation profile provides valuable information on their therapeutic, pharmacological, and toxicological responses.

The chemical and sorption properties of clay minerals from the Mako area, Senegal, were investigated using FTIR spectroscopy, X-ray diffraction, scanning electron microscopy equipped with an X-ray energy dispersion spectrometer, thermal analysis and chemical analysis. The clay sample is essentially dominated by kaolinite and quartz as also shown by treatment with ethylene glycol and dimethylsulfoxide (DMSO). The clay fraction of this natural clay was organically modified by grafting with 3-aminopropyltriethoxysilane (APTES) in order to improve significantly its retention ability of heavy metals. The silane groups of the APTES reagent were partly grafted on the surface of platy kaolinite particles and the remaining ethoxy groups could be hydrolysed by aqueous treatment. The natural clay, its clay fraction and the organo-functionalized clay (with APTES) were investigated as adsorbents for the removal of Pb(II) from aqueous solutions. Evidence for an organic grafting has been demonstrated by comparing the spectroscopic characteristics of the natural clay and those of its chemically modified derivatives. The effects of different parameters (i.e. initial Pb(II) concentration and contact time) on the adsorption efficiency were studied. For an initial concentration of 10 mg L−1Pb(II), the adsorption was maximized after 30 min contact time both for the raw material and its clay fraction and after 90 min for the APTES grafted clay. Although the maximum of sorption for the APTES grafted clay is reached with slower kinetics, this maximum amount of Pb(II) uptake at room temperature (Xmax) is significantly higher since it is 0.99 mg g−1for the raw clay, 1.46 mg g−1for its clay fraction and 3.02 mg g−1for the organically modified clay, i.e. three times greater than the raw clay.

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RésuméLa conformité des variations climatiques récentes observées au Sénégal avec les projections du GIEC est le principal objectif de cet article. Les précipitations et les températures ont été analysées a n de montrer leurs variations en rapport avec les projections du GIEC. Malgré la rupture de 1968, qui marque le début de la baisse de la pluviométrie, nous avons noté une amélioration de celle-ci à partir de 1999. Cela se traduit par l'apparition d'années excédentaires, contrairement à la période 1976-1998. Cette irrégularité de la pluviométrie est en phase avec les projections du GIEC qui décrivent aussi bien des hausses que des baisses pour l' Afrique de l'Ouest, sans pour autant qu'il y ait une raréfaction des événements pluviométriques extrêmes (fortes pluies de 2012 et sécheresse de 2014). L'évolution des températures montre une conformité avec les scénarios du GIEC. En effet, il y a une augmentation des températures de la saison fraîche avec une forte variation interannuelle (-1,8 °C à 1,7 °C). Cette élévation de température est aussi observée pour la saison chaude avec une moindre amplitude (-1,7 °C à 1 °C). La tendance générale à l'échelle annuelle con rme une hausse de la température dont le début correspond avec l'avènement de la sécheresse. Face à cette situation, le Sénégal a entrepris une politique volontariste en matière d'adaptation et d'atténuation, conforme aux engagements internationaux. Mots-clésclimat, variations, Sénégal, scénarios GIEC. AbstractThe conformity of recent climatic variations observed in Senegal with IPCC projections is the main objective of this article. Precipitations and temperatures were analysed to show their variations with respect to IPCC projections. Despite the 1968 rupture which marks the onset of the drop in rainfall, we have noticed an improvement since 1999. That improvement results in the appearance of wet years, contrary to the period 1976-1998. That rainfall irregularity is in phase with IPCC projections which describe increases and decreases as well for West Africa with extreme rainfall events (2012 heavy rains and 2014 drought). Temperatures variation is in conformity with IPCC scenarios. Indeed, there is an increase in temperatures during cool season with signi cant inter annual variation (-1.8°C to 1.7°C). That increase is also observed during the warm season with a lesser extent (-1.7°C to 1°C). The general trend of yearly mean temperatures con rms a rise whose start coincide with the onset of the drought. With such situation, Senegal has initiated a willing policy on adaptation and mitigation matters in conformity with the international engagements. Keywords

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