Rodents of Senegal and their role as intermediate hosts of Hydatigera spp. (Cestoda: Taeniidae)

Hydatigera (Cestoda: Taeniidae) is a recently resurrected genus including species seldom investigated in sub-Saharan Africa. We surveyed wild small mammal populations in the areas of Richard Toll and Lake Guiers, Senegal, with the objective to evaluate their potential role as intermediate hosts of larval taeniid stages (i.e. metacestodes). Based on genetic sequences of a segment of the mitochondrial DNA gene cytochrome c oxidase subunit 1 (COI), we identified Hydatigera parva metacestodes in 19 out of 172 (11.0%) Hubert's multimammate mice (Mastomys huberti) and one out of six (16.7%) gerbils (Taterillus sp.) and Hydatigera taeniaeformis sensu stricto metacestodes in one out of 215 (0.5%) Nile rats (Arvicanthis niloticus). This study reports epidemiological and molecular information on H. parva and H. taeniaeformis in West African rodents, further supporting the phylogeographic hypothesis on the African origin of H. parva. Our findings may indicate significant trophic interactions contributing to the local transmission of Hydatigera spp. and other parasites with similar life-cycle mechanisms. We therefore propose that further field investigations of rodent population dynamics and rodent-borne infectious organisms are necessary to improve our understanding of host–parasite associations driving the transmission risks of rodent parasites in West Africa

Analyse automatique des sucres en milieux complexes. Nouvelles methodologies d'analyse des sucres en chromatographie liquide haute performance et chromatographie en phase supercritique et contribution a l'etude des mecanismes de retention

SIGLEAvailable from INIST (FR), Document Supply Service, under shelf-number : T 82370 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Extraction et analyse de traces d'oligo- et polysaccharides - (application au contrôle qualité des miels)

La lutte contre la fraude dans le domaine agroalimentaire est un souci permanent pour garantir aux consommateurs des produits de qualité. La production limitée et le prix élevé du miel amènent parfois des pratiques de falsification difficiles à déceler tant au niveau de son origine (appellation) que de sa composition (par l ajout délibéré de sirop de sucre bon marché). L analyse des sucres, constituants majoritaires du miel, est l une des méthodes les plus utilisées pour mettre en évidence ces techniques de fraude. Afin de rendre plus efficace les méthodes actuellement utilisées pour l authentification et le contrôle de la qualité des miels, la recherche de nouveaux marqueurs a été entreprise par extraction sur phase solide et chromatographie des oligo- et polysaccharides. Malgré la variabilité des compositions rencontrées dans ces produits naturels, des profils chromatographiques ont permis de caractériser certaines variétés de miel et de détecter des adultérations dès l ajout de 1 % de sirop de sucre. Cette approche amène de nouvelles solutions et perspectives pour certifier l appellation d un miel et contrer les techniques de falsification qui existent sur le marchéThe fight against the fraud in the agro-alimentary field is a permanent problem to warrant quality products to the consumers. The limited production and the high price of honey provoke falsification practices which are difficult to detect on its origin (appellation) and its composition (by the deliberated addition of cheap sugar syrup). The analysis of sugars, major : In order to improve the current methods for the authentification and the quality control of honeys, the search of new probes was undertaken by solid phase extraction and chromatography of oligo- and polysaccharides. In spite of the great variability of the compositions in these natural products, chromatographic fingerprints allowed to discriminate some varieties of honey and to detect adulterations from an addition of 1 % of sugar syrup. This approach leads new solutions and perspectives to certify a variety of honey and to fight against the falsification techniques which exist on the marketLYON1-BU.Sciences (692662101) / SudocSudocFranceF

Experimental study of a VAN network in the French Alps.

International audienc

Hybrid acceleration using real vector automata

Abstract. This paper addresses the problem of computing an exact and effective representation of the set of reachable configurations of a linear hybrid automaton. Our solution is based on accelerating the state-space exploration by computing symbolically the repeated effect of control cycles. The computed sets of configurations are represented by Real Vector Automata (RVA), the expressive power of which is beyond that of the first-order additive theory of reals and integers. This approach makes it possible to compute in finite time sets of configurations that cannot be expressed as finite unions of convex sets. The main technical contributions of the paper consist in a powerful sufficient criterion for checking whether a hybrid transformation (i.e., with both discrete and continuous features) can be accelerated, as well as an algorithm for applying such an accelerated transformation on RVA. Our results have been implemented and successfully applied to several case studies, including the well-known leaking gas burner, and a simple communication protocol with timers.

Photochemical behaviour of propranolol in environmental waters: the hydroxylated photoproducts

International audienceThe UV irradiation of propranolol, one of the beta-blockers currently used in cardiac medicine, was studied. During irradiation, the samples were analysed by LC/MS/MS, using a Waters Symmetry C-18 (3.5 mu m 150 x 2.1 mm) column. The main photoproducts were identified from mono-, di- and tri-hydroxylation of the propranolol naphthalenic skeleton. Hydroxyl group positions were predicted by means of theoretical calculations. Partial charge calculations of the propranolol atoms predicted the formation of four mono-hydroxylated compounds, two of them being the most probable. From these two compounds, three di-hydroxylated compounds were predicted. Then the calculations from the two most probable di-hydroxylated compounds were used to propose three tri-hydroxylated propranolol compounds. It was found that the same hydroxylated photoproducts are formed in pure water and in treatment plant waste water

Polydimethylsiloxane Rods for the Passive Sampling of Pesticides in Surface Waters

In this work, the low cost synthesis of polydimethylsiloxane (PDMS) rods is described, and the performances of this new passive sampling device (in laboratory and in situ) are compared to the passive stir bar sorptive extraction (SBSE) for the monitoring of pesticides from different classes (herbicides, insecticides and fungicides) in surface waters. The influence of synthesis parameters of PDMS rods (i.e., heating temperature, heating time and relative amount of curing agent) were assessed regarding their efficiency for the extraction of the target pesticides through a Hadamard’s experimental design. This allowed the determination of the effect of the three parameters on the sorption of pesticides within four experiments. Thus, specific conditions were selected for the synthesis of the PDMS rods (heating at 80 °C for 2 h with 10% of curing agent). Laboratory experiments led to similar to lower extraction recovery in the PDMS rods in comparison with passive SBSE, depending on the pesticide. The in situ application demonstrated the efficiency of the PDMS rods for the passive sampling of the target pesticides in river water, although lower amounts of pesticides were recovered in comparison with passive SBSE. So, these very low cost PDMS rods could be used as an alternative to passive SBSE for large-scale monitoring campaigns