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of the corresponding conference paper, Funding also obtained by the French Ministry of Agriculture under grant agreement C-2015-09 n°2101755701

Objective: Malaria is a major public health problem in Ghana and many indigenes, especially those in rural areas, resort to the use of medicinal plants to treat the disease. The plants: Persea americana Mill. (Lauraceae), Theobroma cacao L. (Malvaceae) and Tridax procumbens (L.) L. (Compositae) are used solely or in combination with other medicinal plants to manage malaria and its associated conditions. The leaves of the plants which are normally the main parts employed, were studied for their phytochemistry and antiplasmodial activity to establish their chemical profile and verify the antimalarial claim. Methods: Plant materials were subjected to basic phytochemical screening to identify the major secondary metabolites. The aqueous extracts were evaluated against chloroquine-sensitive 3D7 P. falciparum and chloroquine-resistant W2 P. falciparum strains, using the fluorescence-based SYBR® green I method to determine their antiplasmodial activity. Results: Basic phytochemical screening of the leaves revealed the presence of tannins, flavonoids and alkaloids in all three plant materials. T. cacao and P. americana, in addition, contained purine base alkaloids, triterpenoids including saponins. The aqueous extracts of the leaves showed antiplasmodial activity against the chloroquine-sensitive 3D7 P. falciparum (9.50 ± 1.38 ≤ IC50 ≤ 10.15 ± 0.45 µg/mL) and against chloroquine-resistant W2 P. falciparum strains (6.40 ± 1.94 ≤ IC50 ≤ 44.94 ± 1.12 µg/mL). The aqueous extract of T. cacao was the most active and was more active against W2 than 3D7 P. falciparum. Only T. procumbens displayed cytotoxicity (CC50

International audience; Our research deals with the development of a new type of game‐based learning environment: (M)MORPG based on mixed reality, applied in the archaeological domain. In this paper, we propose a learning scenario that enhances players' motivation thanks to individual, collaborative and social activities and that offers a continuous experience between the virtual environment and real places (archaeological sites, museum). After describing the challenge to a rich multidisciplinary approach involving both computer scientists and archaeologists, we present two types of game: multiplayer online role‐playing games and mixed reality games. We build on the specificities of these games to make the design choices described in the paper. The proposed approach aims at raising awareness among people on the scientific approach in Archaeology, by providing them information in the virtual environment and encouraging them to go on real sites. We finally discuss the issues raised by this work, such as the tensions between the perceived individual, team and community utilities, as well as the choice of the entering point in the learning scenario (real or virtual) for the players' involvement in the game.

L'étude morphologique des plantes issues de graines, de l'Igname du complexe #Dioscorea cayenensi - D. rotundata$, a été réalisée par examen en microscopie optique de leur développement, depuis l'embryon dans la graine jusqu'à la jeune plante âgée de deux mois. Au cours du premier mois après le semis des graines, les organes liés étroitement avec la partie basale axiale de la jeune plante s'initient et/ou se développent ; ce sont le cotylédon, les trois premières feuilles, le système racinaire et le tubercule. La première feuille, présente dans l'embryon, est particulière parce qu'elle ne possède pas de bourgeon axillaire. La deuxième feuille devient une écaille à l'aisselle de laquelle se développe un système axillaire important. L'entrenoeud sous-jacent à la troisième feuille est le premier allongement de la tige. Des racines adventives naissent dans la partie axiale basale ; Dès le quinzième jour après le semis, la formation du tubercule est initiée par des divisions anticlines et périclines dans le parenchyme de la région axiale située entre la racine principale et le cotylédon, et enfermée à ce stade dans la gaine cotylédonaire. Deux mois après le semis, le très jeune tubercule s'est structuré avec un apex à vaste méristème couvrant du parenchyme et des faisceaux provasculaires. (Résumé d'auteur)