Abstract: Vector-borne diseases account for 17% of the estimated global burden of all infectious diseases [1]. For most of these, vector control remains the sole method to circumvent transmission and eventually epidemics in the absence of vaccine and/or specific arbovirose treatments. Furthermore, the efficacy of existing insecticides is decreasing due to the development of resistances [2, 3]. The situation urges to find novel insecticide or alternative method for controlling mosquito vectors. Taking into account these elements, in a constantly evolving epidemiological and regulatory context, the need to discover alternative, environmentally friendly, and safer biopesticides appears as crucial. Plants are a source of inspiration for new insecticides discovery as coevolution with phytophagous insects promoted the occurrence of a unique chemical diversity devoted to herbivory resistance at least in part [4, 5]. The insecticidal activity of 160 extracts from 87 species collected in French Guiana were evaluated on Ae. aegypti mosquitoes larvae. It was discovered that Maytenus oblongata Reissek (Celastraceae) stem ethyl acetate extract exhibited promising insecticidal properties, i.e., larvicidal and adulticidal activity against Ae. aegypti under laboratory conditions, without ecotoxicity (essay on Chironomus riparius and Daphnia magna) or cytotoxicity (Test on Ae. albopictus C6/36 cells and two human cell lines: KB and MCR5). Four β-dihydroagrofurane sesquiterpene alkaloids (1-4) and one steroid (5) were isolated from this extract. Compounds 2 (1-benzoyl,4-deoxy-alatamine) and 3 (1,2-dibenzoyl,4-deoxy-alatamine) showed LD50 of 7.75 µg/ml (95% confidence interval: 6.46 – 10.00 µg/ml) and 2.38 µg/ml (95% CI: 1.91 – 2.87 µg/ml), respectively, against Ae. aegypti larvae.
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Abstract: The increasing use of composite materials in industry implies an increasing use of automatic processes between which LCM processes take a large place. The improvement of such processes needs an extensive use of numerical simulations for all the stages of the process. In particular, it is necessary to know how the dry reinforcement is shaped. This paper presents a hyperelastic constitutive model for textile composite reinforcement at large strain based on an additive potential representative to tension and in-plane shearing. The proposed potential is a function of the right Cauchy Green and structural tensor invariants whose choice corresponds to textile composite reinforcement mechanical behaviour. The model is implemented in a user subroutine of ABAQUS/Explicit. The accuracy of the model has been checked and some simulations are performed on deep drawing with hemispheric punch. A good agreement is obtained with experimental forming experiments. © 2011 American Institute of Physics.