Ould Bilal B.,Center International Of Formation Et Of Recherche En Energie Solaire Cifres |
Sambou V.,Center International Of Formation Et Of Recherche En Energie Solaire Cifres |
Ndiaye P.A.,Center International Of Formation Et Of Recherche En Energie Solaire Cifres |
Kebe C.M.F.,Center International Of Formation Et Of Recherche En Energie Solaire Cifres |
Ndongo M.,University of Nouakchott
Renewable Energy | Year: 2010
Potou is an isolated site, located in the northern coast of Senegal. The populations living in this area have no easy access to electricity supply. The use of renewable energies can contribute to the improvement of the living conditions of these populations. The methodology used in this paper consists in Sizing a hybrid solar-wind-battery system optimized through multi-objective genetic algorithm for this site and the influence of the load profiles on the optimal configuration. The two principal aims are: the minimization of the annualized cost system and the minimization of the loss of power supply probability (LPSP).To study the load profile influence, three load profiles with the same energy (94 kW h/day) have been used.The achieved results show that the cost of the optimal configuration strongly depends on the load profile. For example, the cost of the optimal configuration decreases by 7% and 5% going from profile 1 to 2 and for those ones going from 1 to 3. © 2010 Elsevier Ltd.
Houmeida A.,University of Nouakchott |
Heeley D.H.,Memorial University of Newfoundland |
Belknap B.,Eastern Virginia Medical School |
White H.D.,Eastern Virginia Medical School
Journal of Biological Chemistry | Year: 2010
We have studied the mechanism of activation of native cardiac thin filaments by calcium and rigor myosin. The acceleration of the rate of 2′-deoxy-3′-O-(N-methylanthraniloyl)ADP (mdADP) dissociation from cardiac myosin-S1-mdADP-Pi and cardiac myosin-S1-mdADP by native cardiac muscle thin filaments was measured using double mixing stopped-flow fluorescence. Relative to inhibited thin filaments (no bound calcium or rigor S1), fully activated thin filaments (with both calcium and rigor-S1 bound) increase the rate of product dissociation from the physiologically important pre-power stroke myosin-mdADP-Pi by a factor of ∼75. This can be compared with only an ∼6-fold increase in the rate of nucleotide diphosphate dissociation from nonphysiological myosin-mdADP by the fully activated thin filaments relative to the fully inhibited thin filaments. These results show that physiological levels of regulation are not only dependent on the state of the thin filament but also on the conformation of the myosin. Less than 2-fold regulation is due to a change in affinity of myosin-ADP-Pi for thin filaments such as would be expected by a simple "steric blocking" of the myosin-binding site of the thin filament by tropomyosin. Although maximal activation requires both calcium and rigor myosin-S1 bound to the cardiac filament, association with a single ligand produces ∼70% maximal activation. This can be contrasted with skeletal thin filaments in which calcium alone only activated the rate of product dissociation ∼20% of maximum, and rigor myosin produces ∼30% maximal activation. © 2010 by The American Society for Biochemistry and Molecular Biology, Inc.
Barry A.H.,University of Paris 13 |
Barry A.H.,University of Nouakchott |
Dirras G.,University of Paris 13 |
Schoenstein F.,University of Paris 13 |
And 2 more authors.
Materials Characterization | Year: 2014
Nanostructured cobalt powders with an average particle size of 50 nm were synthesized using a polyol method and subsequently consolidated by spark plasma sintering (SPS). SPS experiments performed at 650 C with sintering times ranging from 5 to 45 min under a pressure of 100 MPa, yielded to dense bulk nanostructured cobalt (relative density greater than 97%). X-ray diffraction patterns of the as-prepared powders showed only a face centered cubic (fcc) crystalline phase, whereas the consolidated samples exhibited a mixture of both fcc and hexagonal close packed (hcp) phases. Transmission electron microscopy observations revealed a lamellar substructure with a high density of nanotwins and stacking faults in every grain of the sintered samples. Room temperature compression tests, carried out at a strain rate of 10- 3 s - 1, yielded to highest strain to fracture values of up to 5% for sample of holding time of 15 min, which exhibited a yield strength of 1440 MPa, an ultimate strength as high as 1740 MPa and a Young's modulus of 205 GPa. The modulus of elasticity obtained from the nanoindentation tests, ranges from 181 to 218 GPa. The lowest modulus value of 181 GPa was obtained for the sample with the highest sintering time (45 min), which could be related to mass density loss as a consequence of trapped gases releasing. © 2014 Elsevier Inc.
Ould Ahmedou Salem M.S.,University of Nouakchott |
Mint Lekweiry K.,University of Nouakchott |
Mint Deida J.,University of Nouakchott |
Ould Emouh A.,Teyarett Health Center |
And 3 more authors.
American Journal of Tropical Medicine and Hygiene | Year: 2015
The occurrence of Plasmodium vivax malaria was reported in Nouakchott, Mauritania in the 1990s. Several studies have suggested the frequent occurrence of P. vivax malaria among Nouakchott residents, including those without recent travel history to the southern part of the country where malaria is known to be endemic. To further consolidate the evidence for P. vivax endemicity and the extent of malaria burden in one district in the city of Nouakchott, febrile illnesses were monitored in 2012-2013 in the Teyarett health center. The number of laboratory-confirmed P. vivax cases has attained more than 2,000 cases in 2013. Malaria transmission occurs locally, and P. vivax is diagnosed throughout the year. Plasmodium vivax malaria is endemic in Nouakchott and largely predominates over Plasmodium falciparum. Copyright © 2015 by The American Society of Tropical Medicine and Hygiene.
Lekweiry K.M.,University of Nouakchott |
Salem M.S.O.A.,University of Nouakchott |
Basco L.K.,Institute Of Recherche Biomedicale Des Armees |
Basco L.K.,Aix - Marseille University |
And 3 more authors.
Malaria Journal | Year: 2015
Malaria has become a major public health problem in Mauritania since the 1990s, with an average of 181,000 cases per year and 2,233,066 persons at risk during 1995-2012. This paper provides the first publicly available overview of malaria incidence and distribution in Mauritania. Information on the burden and malaria species distribution is critical for guiding national efforts in malaria control. As the incidence of malaria changes over time, regular updates of epidemiological data are necessary. © 2015 Mint Lekweiry et al.; licensee BioMed Central.