Hybrid client-server and P2P network for web-based collaborative 3D design

National audienceOur proposed research project is to enable 3D distributed visualization and manipulation involving collaborative effort through the use of web-based technologies. Our project resulted from a wide collaborative application research fields: Computer Aided Design (CAD), Building Information Modeling (BIM) or Product Life Cycle Management (PLM) where design tasks are often performed in teams and need a fluent communication system. The system allows distributed remote assembling in 3D scenes with real-time updates for the users. This paper covers this feature using hybrid networking solution: a client-server architecture (REST) for 3D rendering (WebGL) and data persistence (NoSQL) associated to an automatically built peer-to-peer (P2P) mesh for real-time communication between the clients (WebRTC). The approach is demonstrated through the development of a web-platform prototype focusing on the easy manipulation, fine rendering and light update messages for all participating users. We provide an architecture and a prototype to enable users to design in 3D together in real time with the benefits of web based online collaboration

Saladin d’Anglure Bernard, Être et renaître inuit. Homme, femme ou chamane (préface de Claude Lévi-Strauss), Gallimard, coll. « Le langage des contes », Paris, 2006, 429 p. + 8 p. de pl. N&B, bibl., gloss., ill.

Après cinquante années de recherches dans l’Arctique canadien, Bernard Saladin d’Anglure offre à ses proches, à ses informateurs disparus ou vivants, mais aussi au grand public, un premier ouvrage sur les mythes d’origine de la vie humaine chez les Inuit, sur les mythes de différentiation des sexes ou encore sur la relation entre humains et monde animal. Grande synthèse de la kyrielle d’articles scientifiques rédigés au cours de sa carrière, cet ouvrage est un bouquet de mythes et de récits m..

"On ne fait que s'entraider" : dynamique des relations de pouvoir et construction de la figure du leader chez les Inuit du Nunavik (XXe siècle-2011)

Cette thèse est construite sur deux mouvements qui s’entrecroisent : une analyse de la nature des relations de pouvoir et une étude de la construction de la figure du leader chez les Inuit du Nunavik. Elle propose ainsi de déconstruire la catégorie de leader en montrant sa nature endogène, mais réappropriée, tout en offrant une nouvelle perspective analytique sur la question des formes de pouvoir. Outillée par l’anthropologie réflexive, cette recherche doctorale met en évidence la prééminence de la coopération dans le Nunavik contemporain. Au sein même des relations d’entraide, qui dépassent de loin le cadre des échanges alimentaires et matériels pour toucher des dimensions sociales et immatérielles, se manifestent clairement les rapports de pouvoir. Les figures de pouvoir sont des personnes possédant des biens dont d’autres sont dépourvus et dans l’obligation de les partager. Dans le sillage des travaux menés sur les sociétés dites égalitaristes et sur les sociétés dites sans État, cette thèse montre ainsi que la source du pouvoir chez les Inuit est externe. Sa légitimité est conférée par le groupe et il se manifeste dans la contrainte sociale de redistribuer. Le groupe l’institue en décidant, librement, de suivre certaines personnes. Ce schème éclaire sous un nouveau jour la nature du lien tissé entre les Nunavimmiut et les Qallunaat tout au long du XXe siècle. La pression constante que le groupe exerce sur les figures de pouvoir s’étend en effet aux missionnaires ou aux commerçants venant s’installer dans l’Arctique québécois. Alors que ces derniers tentent d’imposer leurs conceptions et d’établir de nouvelles positions de pouvoir, ils sont dans le même temps considérés comme des pourvoyeurs devant partager leur richesse. Il en est de même pour les gouvernements qui s’implantent progressivement dans la région à partir des années 1950. Ceux-ci voient alors s’enliser leur politique paternaliste. Les critiques adressées au projet de gouvernement régional au Nunavik portent elles aussi ces marques. Pour les Nunavimmiut, un gouvernement autonome doit être, avant tout, au service des habitants de la région. Mots clés : Inuit, Nunavik, anthropologie politique, coopération, pouvoir, gouvernement, gouvernance, Canada, anthropologie réflexive.This dissertation describes power relationships among the Nunavik Inuit by addressing two interrelated themes. On the one hand, the nature of power and the role of authority figures are analyzed. On the other, the concept of leader is deconstructed by showing its endogenous nature and the way it is appropriated by Inuit. Through reflexive fieldwork, this research points to a high prevalence of cooperation practices among the Nunavik Inuit. These practices, which are structured by power relationships and various inequalities, cover a wide range of social and material goods and go far beyond food sharing and equipment lending. Such pooling of resources is driven by authority figures who possess what others lack and, as such, are obliged to give back and share their wealth. In line with previous research on egalitarian groups and stateless societies, this research shows that Inuit individuals gain power through exogenous factors, i.e., what others within the group think of them, and not through endogenous ones, i.e., their personal ambitions. In other words, a group creates its leader by deciding to follow him or her. This finding sheds new light on the history of Inuit and Qallunaat relations during the 20th century. Each Inuit group continually exerted pressure to control authority figures, and this pressure extended to missionaries and traders as well. Despite efforts to impose their own power structures by creating new positions of authority in the Arctic, missionaries and traders were nevertheless considered to be wealthy people who had an obligation to share. Governments likewise felt the same pressures, which in time subverted their paternalistic policies. The same applies today to the Nunavik regional government, which recognizes this reality and is seeking to develop a very advanced form of participatory democracy. Keywords: Inuit, Nunavik, Canada, political anthropology, cooperation, power, government, governance, reflexive anthropology

Combination of non-thermal plasma and hetergeneous catalysis for paracetamol degradation in water

International audienceMany researches for the abatement of aqueous pharmaceutical pollutants in water by Advanced Oxidation Processes (AOPs), including electrical discharge plasmas, have been performed in the last decade. In the present study, non-thermal plasma coupled to catalyst was used for the degradation of paracetamol in water. The plasma was produced in a reactor consisting in a multiple needle-to-plate DBD discharge configuration, while catalyst is a metal oxide based catalyst. In order to investigate the influence of the oxide nature, various home-made catalysts (iron or manganese-based), prepared by wet impregnating method, were tested. Comparisons of the results with or without catalyst on the paracetamol degradation and the physico-chemistry of the treated liquids were done, and they showed that the iron-based catalyst presented better results in terms of conversion and mineralization. Concretely, coupling this catalyst to non-thermal plasma, after 30 min of treatment, the paracetamol conversion is 78 % with 45 % mineralization, against 51% and 3% respectively with plasma alone. The paracetamol degradation as a function of the treatment duration was investigated with this catalyst

Regards croisés sur l'étude archéologique des paysages anciens: Nouvelles recherches dans le bassin méditerranéen, en Asie Centrale et au Proche et au Moyen-Orient

International audienceCette publication rassemble la majeure partie des communications présentées dans le cadre ducolloque BH2. Ces contributions reflètent une grande diversité d’approche dans l’étude des paysages anciens,au travers de plusieurs thématiques qui structurent ainsi l’ouvrage. En même temps, elles démontrent ledynamisme de ces jeunes chercheurs dans leur regard sur les paysages d’une même région, sous des anglesparfois bien différents (aménagement du territoire ; interaction Homme / milieu ; méthodes).Les ressources du milieu et notamment leurs stratégies d’exploitation par les sociétés humainessont traitées ici transversalement. Cependant, les communications sont organisées selon cinq thèmesplus spécifiques, miroirs des interactions Homme / milieu. Le premier thème, « Ressources naturelles etacquisition », regroupe des contributions centrées sur la description des ressources disponibles (eau etgisements de silex) et l’acquisition de ressources spécifiques (silex et matériaux destinés à la fabricationde la parure). Ensuite sont abordées les « S tratégies d’implantation et d’aménagements des territoires »,notamment des aménagements hydrauliques de l’âge du Fer du Néguev central aux tours de surveillanceromaines et byzantines du Faynan en Jordanie. Plusieurs communications retracent ensuite l’« Évolutiondiachronique de schémas d’occupation » de la région de Diyala en Iraq et du Leja en Syrie, ainsi quel’expansion des communautés halafiennes en Syrie. Un quatrième thème aborde les « Impacts réciproquesHomme / milieu et leurs conséquences sur l’évolution des paysages » notamment au travers des causesdu déclin des villes de la vallée yéménite du Jawf et de la « crise » du IIIe millénaire. Enfin, le dernierthème, « Approches spécialisées de la restitution des paysages », regroupe des recherches spécifiques telles que l’utilisation des méthodes de prospections géophysiques, les analyses isotopiques des os d’animauxnéolithiques, les études des listes lexicales des vocabulaires sumériens et akkadiens, reflets de la variété desdisciplines qui contribuent à la restitution des paysages anciens

Impact of seasonal and Organ-Related Fluctuations on the anthelmintic properties and chemical profile of Cladium mariscus (L.) Pohl Extracts

The use of plants and their metabolites stands as a promising option to tackle parasitic infections by gastrointestinal nematodes (GIN) in integrated control strategies. Still, the influence of environmental and phenological factors, and their interactions, in the wild on the metabolomics and biological properties of target plant species, is often disregarded. In this work, we hypothesized that variations in the anthelmintic (AH) properties and chemical composition of extracts from the salt tolerant species Cladium mariscus L. Pohl (sawgrass) may be influenced by seasonal factors and organ-parts. To test this hypothesis, acetone/water extracts were prepared from dried biomass obtained from aerial organs collected from sawgrass in consecutive seasons and tested against Haemonchus contortus and Trichostrongylus colubriformis by the larval exsheathment inhibition assay (LEIA) and egg hatching inhibition assay (EHIA). To ascertain the role of plant organ, the activity of leaves and inflorescences extracts from summer samples was compared. The role of polyphenols in the anthelmintic activity depending on GINs and fluctuations across seasons and plant organs was assessed using polyvinylpolypyrrolidone (PVPP), coupled with an in-depth chemical profiling analysis using high-performance liquid chromatography completed with electrospray ionization mass spectrometric detection (HPLC-ESI-MSn). Main differences in anthelmintic activities were observed for summer and autumn samples, for both assays. Moreover, inflorescences' extracts were significantly more active than those from leaves against both parasite species on EHIA and against H. contortus on LEIA. Application of PVPP totally inhibit the AH effects based on EHIA and only partly for LEIA. Non-treated PVPP extracts were predominantly composed of flavan-3-ols, proanthocyanidins, luteolin and glycosylated flavonoids, while two flavonoid glycosides were quantified in all PVPP-treated samples. Thus, the activity of such compounds should be further explored, although some unknown metabolites remain to be identified. This study reinforces the hypothesis of the AH potential of sawgrass and of its polyphenolic metabolites uses as nutraceutical and/or phytotherapeutic drugs.info:eu-repo/semantics/publishedVersio

Selective oxidation of hydrocarbons in a catalytic dense membrane reactor: Catalytic properties of BIMEVOX (Me = Ta)

Used as dense membranes in a catalytic dense membrane reactor, Bi2V0.8Ta0.2O5.5 (BITAVOX) is more or less active in the oxidation of propane, ethane and propene according to its surface roughness. When the surface roughness is low, membranes are poorly active in the oxidation of propane (Conversion < 2%). CO and propene are the main products and the stability is high over long experimental periods. BITAVOX membranes with increased surface roughness exhibit high conversions in the oxidation of propane, ethane and propene. Activities and selectivities evolve with time. In a first short period (<250s), products are similar to those of polished samples, then mainly H2 and CO are produced and subsequently H2 and coke. These evolutions are probably related to surface and sub-surface restructuring due to an insufficient oxygen supply through the membrane to face the high catalytic activity induced by the increase in surface area. The results suggest that the O2- diffusion is limited by the low electronic conductivity of BIMEVOX materials. Nevertheless the membrane is not reduced irreversibly, even in coking conditions. This is confirmed by ex-situ characterisations carried out on the materials (XRD, SEM, XPS). An improvement of the electronic conductivity of this material is necessary in order to stabilize the intermediate catalytic behaviour which is interesting for syngas or H2 production from light hydrocarbons

Persistent paléosurfaces in the basement of French Massif Central: geodynamic implications.

National audienceThe siderolithic paleoweathering surfaces of the French Central Massif have been dated to the Late Jurassic/Early Cretaceous, contrasting with previously accepted Tertiary age and implying that the Massif has never hosted a thick sedimentary cover. This contradicts with former thermochronological results. Herein, we expose the arguments for and against the proposed geodynamic evolution of the French Massif Central constrained by paleomagnetic age determinations

Bi2V1-xMexO5.5-y (Me = Ta, Ni) Membranes for Selective Oxidation of C1-C3 Alkanes in a Catalytic Dense Membrane Reactor

Pure and Me-doped Bi2V1-xMexO5.5-y (BIMEVOX) (Me = Ta, Ni) materials exhibit a transient behaviour during the oxidation of C1-C3 alkanes when shaped as dense membranes separating two compartments fed with diluted hydrocarbon and with air, respectively (catalytic dense membrane reactor). Alkenes are first produced at low conversion and CO and H2 follow at higher conversion. The H2/CO ratio increases up to values close to the stoichiometric ones and continues to increase after a peak of activity during which coke builds up. The same transient phenomena as initially observed happen after burning the coke by replacing diluted hydrocarbon by air. This in situ regeneration of the membrane means that the structure and integrity of the membranes have not been modified, as indeed shown by physicochemical analyses (XRD, SEM, XPS). The catalytic properties are mainly related to the presence of ME which affects the electronic conductivity of the materials. At variance with quite neutral BITAVOX, the behaviour of BINIVOX is close to that of BICOVOX which is also a p-type semiconductor. Only BINIVOX is able to oxidise methane (conversion ca. 22-25 mol%) to syngas at low temperature (650°C) in a quite steady manner

Catalytic dense membranes of doped Bi4V2O11 (BIMEVOX) for selective partial oxidation: chemistry of defects versus catalysis

A catalytic dense membrane reactor (CDMR) is used to physically separate the reaction step from the reoxidation of the catalyst. By decoupling the redox mechanism prevailing in mild oxidation of hydrocarbons, the operating conditions may be optimized resulting in an increase of selectivity. The membranes are made up of BIMEVOX oxides, obtained by partial substitution of V in Γ-Bi4V2O11 by ME (Co, Cu, Ta). Experiments performed on BIMEVOX dense membranes using propene and propane are described in terms of, (i) active sites on polished or unpolished surfaces, (ii) operating conditions (T, pO2 in the high oxygen partial pressure compartment), which determine the selectivity, either to mild oxidation products (acrolein, hexadiene, CO), or to partial oxidation products (CO, H2), and, (iii) nature of ME cations and relative properties. The discussion deals with the respective role of electronic vs. oxide ion conductivities which depend on defects in the structure as well as on the redox properties of cations