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Antananarivo, Madagascar

University of Antananarivo is the primary public university of Madagascar, located in the capital Antananarivo.The university traces its founding to 16 December 1955 and the formation of the Institute for Advanced Studies in Antananarivo. It established itself as the main center for higher education in the country, and was renamed the University of Madagascar in 1961. It later opened five more branches in Antsiranana, Fianarantsoa, Toamasina, Toliara, and Mahajanga.In 1988 all branches of the system became independent of each other, and the name University of Madagascar was dropped, with the Antananarivo campus becoming the University of Antananarivo. Wikipedia.

Jugeau F.,Federal University of Rio de Janeiro | Narison S.,French National Center for Scientific Research | Narison S.,Abdus Salam International Center For Theoretical Physics | Ratsimbarison H.,University of Antananarivo
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

Considering the classical two-point correlators built from (axial-) vector, scalar qq and gluonium currents, we confront results obtained using the SVZ⊕1/q2-expansion to the ones from some QCD holographic models in the Euclidean region and with negative dilaton Φi(z)=-|ci2|z2. We conclude that the presence of the 1/q2-term in the SVZ-expansion due to a tachyonic gluon mass appears naturally in the Minimum Soft-Wall (MSW) and the Gauge/String Dual (GSD) models which can also reproduce semi-quantitatively some of the higher dimension condensate contributions appearing in the OPE. The Hard-Wall model shows a large departure from the SVZ⊕1/q2-expansion in the vector, scalar and gluonium channels due to the absence of any power corrections. The equivalence of the MSW and GSD models is manifest in the vector channel through the relation of the dilaton parameter with the tachyonic gluon mass. For approximately reproducing the phenomenological values of the dimension d=4, 6 condensates, the holographic models require a tachyonic gluon mass (αs/π)λ2≈-(0.12-0.14) GeV2, which is about twice the fitted phenomenological value from e+e- data. The relation of the inverse length parameter ci to the tachyonic gluon mass also shows that ci is channel dependent but not universal for a given holographic model. Using the MSW model and Mρ=0.78 GeV as input, we predict a scalar qq mass MS≈(0.95-1.10) GeV and a scalar gluonium mass MG≈(1.1-1.3) GeV. © 2013. Source

Nepomichene T.N.J.J.,Institute Pasteur Of Madagascar | Nepomichene T.N.J.J.,University of Antananarivo | Tata E.,Institute Pasteur Of Madagascar | Boyer S.,Institute Pasteur Of Madagascar
Malaria Journal

Background: Indoor spraying of insecticides and the use of insecticide-treated bed nets are key strategies for national malaria vector control in the central highlands of Madagascar. During the year 2013, malaria outbreaks were reported by the National Malaria Control Programme in the highlands, including the district of Ankazobe. Methods: Entomological trapping was carried out in April and May 2013 and in March 2014, using human landing catches, collection of mosquitoes resting in stables and in houses by oral aspirators, and Centers for Disease Control and Prevention light traps. Detection of Plasmodium in mosquitoes was carried out on head and thorax of anopheline females by ELISA, CSP and PCR (Plasmodium falciparum, Plasmodium malariae, Plasmodium vivax, or Plasmodium ovale). Human biting rate (HBR), sporozoite index and entomological infection rate (EIR) were calculated for Anopheles funestus, Anopheles arabiensis, Anopheles mascarensis, and Anopheles coustani. Results: In Ankazobe district, the presence of malaria vectors such as An. funestus, An. arabiensis and An. mascarensis was confirmed, and a new and abundant potential vector, An. coustani was detected. Indeed, one individual of An. funestus and two An. coustani were detected positive with P. falciparum while one An. mascarensis and four An. coustani were positive with P. vivax. For An. coustani, in March 2014, the EIR varied from 0.01 infectious bites/person/month (ipm) outdoors to 0.11 ipm indoors. For An. funestus, in April 2013, the EIR was 0.13 ipm. The highest HBR value was observed for An. coustani, 86.13 ipm outdoors. The highest sporozoite rate was also for An. coustani, 9.5 % of An. coustani caught in stable was sporozoite positive. Conclusion: The implication of An. coustani in malaria transmission was not previously mentioned in Madagascar. Its very high abundance and the detection of Plasmodium coupled with an opportunistic feeding behaviour in villages with malaria cases supports its role in malaria transmission in Madagascar. © 2015 Nepomichene et al. Source

Thiele D.,Johannes Gutenberg University Mainz | Razafimahatratra E.,University of Antananarivo | Hapke A.,Johannes Gutenberg University Mainz
Molecular Phylogenetics and Evolution

Unequal degrees of taxonomic subdivision can pose problems for research that relies on cross-taxon comparisons of biogeographic patterns. Numerous species of lemurs have been described in recent years. These descriptions were unevenly distributed over the genera of lemurs as exemplified by the closely related mouse lemurs (. Microcebus spp.) and dwarf lemurs (. Cheirogaleus spp.). According to previous studies, these genera display striking differences such as many versus few species, small versus large distributions, and small versus large mitochondrial divergence within and between species. We questioned if these differences reflect the biological reality or a biased taxonomic subdivision, which might be partially due to relatively small amounts of available genetic data from dwarf lemurs. We complemented existing datasets with genetic data from 51 dwarf lemurs from nine sites in southern Madagascar. We analyzed the mitochondrial cytb gene and the nuclear loci adora3, fiba, and vWF. Based on a comparison of mitochondrial genetic data from both genera, we delineated eight hypothetical subgroups within two recognized Cheirogaleus species. We used mitochondrial and nuclear data to reconstruct species trees and to estimate divergence times between Microcebus species and Cheirogaleus subgroups. We further performed Bayesian species delimitations based on nuclear sequence data from Cheirogaleus subgroups. Strong signals in mitochondrial and nuclear data indicate the existence of deeply divergent, distinct groups within recognized Cheirogaleus species. Based on several lines of evidence, we conclude that the species diversity in Cheirogaleus has been underestimated so far. We delineate six species among the eight subgroups and provide a formal description for one new Cheirogaleus species. © 2013 Elsevier Inc. Source

Dewar R.E.,Yale University | Radimilahy C.,University of Antananarivo | Wright H.T.,University of Michigan | Wright H.T.,Santa Fe Institute | And 3 more authors.
Proceedings of the National Academy of Sciences of the United States of America

Past research on Madagascar indicates that village communities were established about AD 500 by people of both Indonesian and East African heritage. Evidence of earlier visits is scattered and contentious. Recent archaeological excavations in northern Madagascar provide evidence of occupational sites with microlithic stone technologies related to foraging for forest and coastal resources. A forager occupation of one site dates to earlier than 2000 B.C., doubling the length of Madagascar's known occupational history, and thus the time duringwhich people exploited Madagascar's environments. We detail stratigraphy, chronology, and artifacts from two rock shelters. Ambohiposa near Iharana (Vohémar) on the northeast coast, yielded a stratified assemblage with small flakes, microblades, and retouched crescentic and trapezoidal tools, probably projectile elements, made on cherts and obsidian, some brought more that 200 km. 14C dates are contemporary with the earliest villages. No food remains are preserved. Lakaton'i Anja near Antsiranana in the north yielded several stratified assemblages. The latest assemblage is well dated to A.D. 1050-1350, by 14C and optically stimulated luminescence dating and pottery imported from the Near East and China. Below is a series of stratified assemblages similar to Ambohiposa. 14C and optically stimulated luminescence dates indicate occupation from at least 2000 B.C. Faunal remains indicate a foraging pattern. Our evidence shows that foragers with a microlithic technology were active in Madagascar long before the arrival of farmers and herders and before many Late Holocene faunal extinctions. The differing effects of historically distinct economies must be identified and understood to reconstruct Holocene histories of human environmental impact. © PNAS 2013. Source

Rakotondralambo J.,University of Antananarivo
Physics Letters, Section A: General, Atomic and Solid State Physics

We introduce the notion of integrating factor for a 1-form which is an inner product of a vector fields and a 2-form, and the notion of weakly bi-Hamiltonian field also, which is locally quasi-bi-Hamiltonian. A cohomological class in some first cohomology space is associated to such vector fields when this is weakly bi-Hamiltonian and defined relatively to the above 1-form. This class is a cohomological obstruction to the existence of a global integrating factor for the 1-form. © 2011 Elsevier B.V. All rights reserved. Source

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