EVALUATION DE LA TOXICITÉ AIGUË DE L’EXTRAIT AQUEUX DES FEUILLES DE THUNBERGIA ATACORENSIS, UNE ESPÈCE NOUVELLE

Thunbergia atacorensis is a new plant species, discovered in gallery forest of Atacora Province in Benin (West Africa). This beautiful shrub can be used as ornamental. Before introducing the plant in human environment, it will be necessary to know its toxicological parameters. This work was aimed to evaluate, in mice, the acute toxicity at different doses of the aqueous decoction of the plant leaves in order to prevent intoxication. The acute toxicity of leaves aqueous decoction from the plant was assessed after a process which consisted in giving orally, to mice, the crude decoction for increasing doses ranging from 900 to 4500 mg/kg of body weight (b.w.). The use of the plant extract, through oral route (or), at different doses, causes some clinical signs (agitations, poor appetite, motor difficulties and dyspnea). The results made it possible to obtain the dose at bordering on solubility which squares with the Letal Dose of 100% or LD100 (4500 mg/kg/b.w./or). The Tolerated Maximal Dose or TMD was evaluated at 900 mg/kg/b.w./or. The plant extract, administered orally, provided slight toxicity, with a LD50 of 1720.25 mg/kg/b.w./or. Thus, the experimentally found Letal Dose of 50% can justify the domestication of the plant as ornamental

Variable selection in multivariate linear regression with random predictors

We propose a method for variable selection in multivariate regression with random predictors. This method is based on a criterion that permits to reduce the variable selection problem to a problem of estimating a suitable set. Then, an estimator for this set is proposed and the resulting method for selecting variables is shown to be consistent. A simulation study that permits to study several properties of the proposed approach and to compare it with existing methods is given

EVALUATION DE LA TOXICITÉ AIGUË DE L’EXTRAIT AQUEUX DES FEUILLES DE THUNBERGIA ATACORENSIS, UNE ESPÈCE NOUVELLE

Thunbergia atacorensis is a new plant species, discovered in gallery forest of Atacora Province in Benin (West Africa). This beautiful shrub can be used as ornamental. Before introducing the plant in human environment, it will be necessary to know its toxicological parameters. This work was aimed to evaluate, in mice, the acute toxicity at different doses of the aqueous decoction of the plant leaves in order to prevent intoxication. The acute toxicity of leaves aqueous decoction from the plant was assessed after a process which consisted in giving orally, to mice, the crude decoction for increasing doses ranging from 900 to 4500 mg/kg of body weight (b.w.). The use of the plant extract, through oral route (or), at different doses, causes some clinical signs (agitations, poor appetite, motor difficulties and dyspnea). The results made it possible to obtain the dose at bordering on solubility which squares with the Letal Dose of 100% or LD100 (4500 mg/kg/b.w./or). The Tolerated Maximal Dose or TMD was evaluated at 900 mg/kg/b.w./or. The plant extract, administered orally, provided slight toxicity, with a LD50 of 1720.25 mg/kg/b.w./or. Thus, the experimentally found Letal Dose of 50% can justify the domestication of the plant as ornamental

Development of an SPME-GC-MS method for the specific quantification of dimethylamine and trimethylamine: use of a new ratio for the freshness monitoring of cod fillets

International audienceBACKGROUND: Fish is a highly perishable food, so it is important to be able to estimate its freshness to ensure optimum quality for consumers. The present study describes the development of an SPME‐GC‐MS technique capable of quantifying both trimethylamine (TMA) and dimethylamine (DMA), components of what has been defined as partial volatile basic nitrogen (PVB‐N). This method was used, together with other reference methods, to monitor the storage of cod fillets (Gadus morhua) conserved under melting ice.RESULTS: Careful optimisation enabled definition of the best parameters for extracting and separating targeted amines and an internal standard. The study of cod spoilage by sensory analysis and TVB‐N assay led to the conclusion that the shelf‐life of cod fillet was between 6 and 7 days. Throughout the study, TMA and DMA were specifically quantified by SPME‐GC‐MS; the first was found to be highly correlated with the values returned by steam distillation assays. Neither TMA‐N nor DMA‐N were able to successfully characterise the decrease in early freshness, unlike dimethylamine/trimethylamine ratio (DTR), whose evolution is closely related to the results of sensory analysis until the stage where fillets need to be rejected.CONCLUSION: DTR was proposed as a reliable indicator for the early decrease of freshness until fish rejection

Impact and cost-effectiveness of a lethal house lure against malaria transmission in central Côte d'Ivoire : a two-arm, cluster-randomised controlled trial

Background: New vector control tools are required to sustain the fight against malaria. Lethal house lures, which target mosquitoes as they attempt to enter houses to blood feed, are one approach. Here we evaluated lethal house lures consisting of In2Care (Wageningen, Netherlands) Eave Tubes, which provide point-source insecticide treatments against host-seeking mosquitoes, in combination with house screening, which aims to reduce mosquito entry. Methods: We did a two-arm, cluster-randomised controlled trial with 40 village-level clusters in central Côte d'Ivoire between Sept 26, 2016, and April 10, 2019. All households received new insecticide-treated nets at universal coverage (one bednet per two people). Suitable households within the clusters assigned to the treatment group were offered screening plus Eave Tubes, with Eave Tubes treated using a 10% wettable powder formulation of the pyrethroid β-cyfluthrin. Because of the nature of the intervention, treatment could not be masked for households and field teams, but all analyses were blinded. The primary endpoint was clinical malaria incidence recorded by active case detection over 2 years in cohorts of children aged 6 months to 10 years. This trial is registered with ISRCTN, ISRCTN18145556. Findings: 3022 houses received screening plus Eave Tubes, with an average coverage of 70% across the intervention clusters. 1300 eligible children were recruited for active case detection in the control group and 1260 in the intervention group. During the 2-year follow-up period, malaria case incidence was 2·29 per child-year (95% CI 1·97–2·61) in the control group and 1·43 per child-year (1·21–1·65) in the intervention group (hazard ratio 0·62, 95% CI 0·51–0·76; p<0·0001). Cost-effectiveness simulations suggested that screening plus Eave Tubes has a 74·0% chance of representing a cost-effective intervention, compared with existing healthcare activities in Côte d'Ivoire, and is similarly cost-effective to other core vector control interventions across sub-Saharan Africa. No serious adverse events associated with the intervention were reported during follow-up. Interpretation: Screening plus Eave Tubes can provide protection against malaria in addition to the effects of insecticide-treated nets, offering potential for a new, cost-effective strategy to supplement existing vector control tools. Additional trials are needed to confirm these initial results and further optimise Eave Tubes and the lethal house lure concept to facilitate adoption. Funding: The Bill & Melinda Gates Foundation

Conception de logiciels destines a des utilisateurs non-informaticiens : cas d'un systeme relationnel de gestion de fichiers

SIGLECNRS T Bordereau / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Sur l'existence de lois orthogonales échangeables ou stationnaires et la loi forte des grands nombres

PARIS13-BU Sciences (930792102) / SudocSudocFranceF