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International audience; Poly(L-Lactide) (PLLA) is a semi-crystalline biopolymer of great interest due to its biosourced, biocompatible and compostable nature. However, its brittleness prevents its use in a wide range of applications. In order to reinforce PLLA, it is often used in polymer blends or in composites. In this contribution, an unprecedented family of PLLA-based / glass fabrics composites with poly(L-lactide-co--caprolactone) statistical copolymers as the matrix is reported. These biocomposites were produced in one step synthesis by in situ copolymerization of L-lactide and -caprolactone in Thermoplastic Resin Transfer Molding (TP-RTM) process. These materials display high matrix/fabrics wettability along with strong rubbery character.

International audience; The recycling of thermoset-based composites is challenging. The replacementof thermosetting resins with thermoplastics is an initial step to address thisissue, together with the use of green reinforcements. Owing to the recentdevelopment of low-viscosity thermoplastic resins, it is possible to producethermoplastic matrix composites using the resin transfer molding (RTM) technique,which was originally conceived for the production of thermosettingmatrix composites. These resins are based on cyclic esters, methyl methacrylate,and cyclic (butylene terephthalate) oligomers. This review presents thestate-of-the-art works reported on the production of thermoplastic matrix compositesvia a thermoplastic RTM (TP-RTM) process, from the in situ polymerizationof the resins through the optimization of the TP-RTM parameters forthe evaluation of the composite properties.

The coexistence of grass and trees that typifies savanna ecosystems is maintained in part by top-down forces including herbivory and fire. Understanding fire-herbivore interactions is an integral step in determining the effect of these forces individually and informs decisions about the use of fire as a livestock management technique. The magnet effect, in which grazers are drawn to an area after it is burned, is one such interaction between fire and herbivores. While the process of the magnet effect has been described, neither its longevity nor the manner through which fire intensity affects its strength is understood. In this study, we explored whether the increase in herbivory pressure predicted by the magnet effect is maintained over long periods after a fire, how fire intensity influences the strength of the magnet effect, and which feeder types are most influenced by the magnet effect. We established five field sites at the Mpala Research Centre in Laikipia, Kenya that ranged in fire intensity and elapsed time since last the burn. We found that the magnet effect is transient on a seven-year scale and affects grazers more than browsers or mixed feeders, though herbivory and grass biomass responses to fire intensity were conflicting. This research clarifies the role of the magnet effect in maintaining savanna ecosystems and can aid agriculturalists seeking to use fire as a management technique by indicating how long after a burn increased palatability of grass can be expected., Consilience, No 14 (2015): Issue Fourteen: 2015

Herbivory is a prominent top-down force shaping the landscape of semi-arid savannas in East Africa. Herbivores participate in seed dispersal both by ingesting and defecating the seeds of endozoochorously-dispersed plants and by translocating the seeds of exozoochorously-dispersed plants. In this study, we sought to determine how the extinction of large mammalian herbivores would affect the abundance of five focal species of plants that use fruiting as theira primary dispersal mechanism. We also examined how the absence of large mammalian herbivores affected seed predation by small mammals. We counted the number of individual plants for each of the five species in three short-term (5 yearr. old) exclusion blocks and one long-term (15 yearr. old) exclusion block. We found that total abundance of fleshy-fruited species increaseds as successive levels of large mammalian herbivores weare excluded and as the duration of herbivore exclusion increaseds. Within species, we found that C. orthacantha and S. campylacanthum increased in the absence of herbivores, while O. stricta decreased in the absence of herbivores. B. aegyptiaca and B. albitrunca did not exhibit differences in abundance between different levels of herbivore exclosure. We found that small mammals demonstrated a preference for B. albitrunca and O. stricta seeds, which were consumed primarily by the fringe-tailed gerbil, Gerbilliscus robustus. Understanding the interactions between herbivores and vegetation is vital to conserving understanding how plant communities as well as understanding how they may change in the future, as well as how to conserve them., Consilience, No 13 (2015): Issue Thirteen: 2015