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International audience; This research is part of the Artificial Intelligence Virtual Trainer (AI-VT) project which aims to create a system that can identify the user's skills from a text by means of machine learning. AI-VT is a case-based reasoning learning support system can generate customized exercise lists that are specially adapted to user needs. To attain this outcome, the relevance of the first proposed exercise must be optimized to assist the system in creating personalized user profiles. To solve this problem, this project was designed to include a preliminary testing phase. As a generic tool, AI-VT was designed to be adapted to any field of learning. The most recent application of AI-VT was in the field of computer science specifically in the context of the fundamentals of algorithmic learning. AI-VT can and will also be useful in other disciplines. Developed in Python with the Keras API and the Tensorflow framework, this artificial intelligence-based tool encompasses a supervised learning environment, multi-label text classification techniques and deep neural networks. This paper presents and compares the performance levels of the different models tested on two different data sets in the context of computer programming and algorithms.

International audience; Determining valuable data among large volumes of data is one of the main challenges in Big Data. We aim to extract knowledge from these sources using a Hierarchical Multi-Label Classification process called Semantic HMC. This process automatically learns a label hierarchy and classifies items from very large data sources. Five steps compose the Semantic HMC process: Indexation, Vectorization, Hierarchization, Resolution and Realization. The first three steps construct automatically the label hierarchy from data sources. The last two steps classify new items according to the label hierarchy. This paper focuses in the last two steps and presents a new highly scalable process to classify items from huge sets of unstructured text by using ontologies and rule-based reasoning. The process is implemented in a scalable and distributed platform to process Big Data and some results are discussed.

International audience; This work experimentally addresses aluminum combustion in steam, pure or mixed with diluents, for aluminum particles in size range 40 ∼80 μm, using an electrodynamic levitator. High-speed videos unveil an unreported and complex mechanism in steam, not observed in other oxidizers. The detached flame is quite faint and very close to the surface. Alumina smoke around the droplet rapidly condenses and coalesces into a large, single orbiting alumina satellite. It eventually collides the main aluminum droplet while generating secondary alumina droplets. A unique feature is the presence of several distinct oxide lobes on the droplet, which merge only at the end of burning and encapsulate the remaining aluminum, possibly promoting an incomplete combustion. The measured burning times in pure water vapor are longer than expected and the efficiency of steam is found to be 30% that of oxygen, lower than the usually accepted value of 60%. A general correlation on burning time, including the major oxidizers, is proposed. Direct numerical simulations are conducted and are in line with experiments, in terms of burning rate or flame stand off ratio. Combustion in steam seems mostly supported by surface reactions, giving a faint flame with low gas temperatures and high hydrogen content. It is speculated that those two specific features could help explain the peculiarity of steam.

National audience; La région de Franche-Comté figure parmi les territoires les plus boisés au niveau national avec un taux de boisement de 46 %, dans un espace européen où la couverture forestière représente plus de 40 % de la surface totale. Les espaces forestiers constituent donc un enjeu important en termes de ressource énergétique et économique, de valeur patrimoniale et de bien-être des populations. C’est dans ce contexte que le chantier Construction Historique des Espaces Forestiers (CHEF) vise à produire une meilleure connaissance des espaces forestiers actuels, avec une perspective de longue durée, de la Protohistoire au XXème siècle. Cette étude, qui offre un recul suffisant, permet d’aborder des questions de gestion durable.Pour mener à bien ce travail, la forêt de Chailluz à Besançon a été choisie comme zone pilote pour plusieurs raisons. Tout d’abord, ce massif forestier communal périurbain est caractérisé par sa multifonctionnalité. Elle a en effet une fonction économique par sa production sylvicole, une fonction écologique car elle comporte une Zone Naturelle d'Intérêt Ecologique Faunistique et Floristique (ZNIEFF) et une fonction sociale car elle est fréquentée comme espace éducatif, de loisirs et de pratique sportive. Chailluz constitue également un cas d’étude intéressant par son ancienneté : dès les années 1180-1190, les Bisontins sont en litige avec l’archevêque pour y obtenir des droits d’usage (Fohlen dir. 1964). De nouveaux conflits en 1232 où le bois est mentionné sous l'appellation "Chaillou" à propos d'un droit de défrichagepuis en 1258 lors d'un droit d'affouage, où le bois est alors appelé "Chalor" montrent que l’archevêque est le seul propriétaire. Mais dès 1290, les Bisontins légifèrent dans la forêt de Chailluz où ils ont désormais des droits. La forêt est alors mentionnée de manière explicite dans un règlement relatif aux coupes en 1309 . Paradoxalement, en dehors de la chapelle St Gengoul, de structures militaires autour du fort de la Dame Blanche, de quelques lavognes pour abreuver du bétail et de quelques découvertes isolées signalées à la carte archéologique, jusqu’en 2009, le patrimoine archéologique de Chailluz restait méconnu et très largement sous-estimé. C’est grâce à une acquisition de données altimétriques par laser aéroportée (LiDAR) que le massif s'est révélé très riche en structures d'habitat, agropastorales, de voirie et de production économique. Ces découvertes ont permis de reconsidérer le massif forestier de Chailluz comme un espace dynamique dont l'usage et le rôle au sein du territoire bisontin a sans doute considérablement varié, à l'instar d'autres forêts anciennes comme le massif de Haye en Lorraine ou du Châtillonnais en Bourgogne (Georges-Leroy et al. 2012, Goguey et al. 2014).Ainsi, il convenait de s'interroger sur les emprises du massif forestier au cours de périodes passées et éventuellement de cerner la zone la plus ancienne. Un second niveau de questions visait à comprendre les rythmes et les modalités de déboisement / reboisement en fonction des activités (agropastorale, charbonnage, extraction...) dont l'existence est prouvée par les vestiges conservés et qui sont parfois attestées plus ou moins directement par les textes. Enfin, un troisième niveau de questions vise à mieux comprendre la forêt dans son état actuel en essayant d'évaluer l'influence des pratiques domestiques, extractive et productive, agropastorales et sylvicoles anciennes sur la structure du boisement et la végétation d'aujourd'hui. Dans cet article, nous nous attacherons à présenter l’apport de la technologie LiDAR pour ce type de problématique et la manière dont elle peut s’intégrer dans une démarche interdisciplinaire et multi-échelle.

National audience; L’analyse des données altimétriques, acquises par télédétection lidar (laser aéroporté), permet de détecter des traces de mise en valeur des zones humides qui remet ces espaces au coeur du système productif des territoires du passé et non pas systématiquement à leur marge. Pour illustrer le potentiel de la technologie lidar pour l’archéologie des paysages, cet article présente deux cas d’étude l’un en Franche-Comté et l’autre en Languedoc oriental.

International audience; N2O contributes to increasing the greenhouse effect and is also involved in stratospheric ozone depletion. In soil and water, N2O reductase catalyses the reduction of N2O into the inert form N2. N2O reductase activity is known to be affected by acidic conditions and the application of liming materials to acidic soils is now proposed as a solution for mitigating soil N2O emissions. During a one-year laboratory experiment, we studied the functioning of N2O reductase after the application of calcium carbonates to an acidic soil with a very low capacity to reduce N2O. The functioning of N2O reductase was characterised through anaerobic incubations using the acetylene inhibition technique combined with a logistic model to determine the main enzyme functioning characteristics (latency, maximal rate). Both changes in soil pH and soil capacity to reduce N2O were rapidly observed after the application of lime materials. The activity of N2O reductase was observed to be efficient throughout the experiment even when the soil had returned to initial acidic conditions, revealing a hysteretic response of N2O reductase to pH variations. Nevertheless, some signs of lower N2O reductase activity over time were observed mainly after 200 days of applying lime materials. Altogether, these results suggest that, in this soil condition, the beneficial impact of the application of liming materials on N2O emissions could last longer than this on soil pH.

International audience; Aluminum particles are widely used as an additive to increase energetic performances. Recently, Aluminum has also received a growing interest as a source of hydrogen for fuel cell applications, or in novel power generation concepts as it provides a carbon-free energy that meets current policies for reducing emissions of greenhouse gases. Our recent studies focused on the description of the combustion process varying ambient conditions (pressure and oxidizer). Only the second stage of the combustion process, after the establishment of a steady state, was scrutinized. The proposed work sheds light more specifically to the initial stages where the particle is warmed up from the initial state to a thermal runaway condition. Indeed, the question arises at what temperature do these condensed fuels burst into flames, knowing that the presence of a passive coat greatly influences the process.For this study, a dedicated set-up has been improved. It consists of an electrodynamic levitator in which a single particle, trapped by electrostatic forces, burns in a controlled atmosphere. A two-color ratio pyrometer has been specifically assembled with photomultipliers (PM) to obtain the time evolution of mean surface temperature. The PM signals are synchronised witha particle visualization device that is composed of a high-speed camera combined with a long-distance microscope. Subsequently, the temperature measurement of high temporal resolution can then be associated for the first time at a rate of 250 000 fps with the fast-apparent phenomenology of the pre-ignition processes. In addition, the spatial resolution of the visualization (1.92 μm/pix) allows the interpretation of the PM signals to be commented.

International audience; Shoreline position varies over a wide range of temporal and spatial scales in response to a variety of processes. The monitoring of its position changes requires availability of high-frequency observations over a long period. In this study, the low-cost crowd-sourced system CoastSnap (Harley et al., 2019) is used to investigate the shoreline dynamics at the embayed beach of Lafitenia over a 9months period. After the validation of CoastSnap images rectification thanks to in situ surveyed data, a quantitative analyse of cross-shore position changes is undertaken using high tide waterline. The obtained results show apparent short time scale beach rotation for the first time at Lafitenia. This new shoreline mapping approach offers new perspectives to study short time coastal processes over long periods.

Ce texte constitue le prologue du numéro 11 du Journal on Interdisciplinary Methodologies and Issues in Science : Penser l'interdisciplinarité en pratique. L'ensemble des 10 contributions est brièvement présenté à partir des fondements qui font l'interdisciplinarité en pratique : les dispositions des chercheurs, leur posture indisciplinaire et le contexte complexe dans lequel s'opère l'interdisciplinarité.

International audience; The olfactory mucosa (OM) and olfactory bulb (OB) are neuronal tissues that contribute to the early processing of olfactory information. They contain significant amounts of n-3 and n-6 polyunsaturated fatty acids (PUFAs), which are crucial for neuronal tissue development. In this study, we evaluated the impact of feeding mice diets that are either deficient in α-linolenic acid (ALA) or supplemented with n-3 long-chain PUFAs from gestation to adolescence on the phospholipid and ganglioside composition of these tissues. Both diets modified the levels of some phospholipid classes, notably the phosphatidylserine and phosphatidylethanolamine levels. In addition, the low-ALA diet enriched n-6 PUFAs in the main phospholipid classes of both tissues, while the diet supplemented with n-3 PUFAs enhanced the n-3 PUFA-containing phospholipid species level, mainly in OM. The diets also modulated the levels and profiles of several ganglioside classes in OM and OB. These modifications may have repercussions on the olfactory sensitivity.

International audience; Aluminum particles are widely used as an additive to increase energetic performances. Recently, Aluminum has also received a growing interest as a source of hydrogen for fuel cell applications, or in novel power generation concepts as it provides a carbon-free energy that meets current policies for reducing emissions of greenhouse gases. Our recent studies focused on the description of the combustion process varying ambient conditions (pressure and oxidizer). Only the second stage of the combustion process, after the establishment of a steady state, was scrutinized. The proposed work sheds light more specifically to the initial stages where the particle is warmed up from the initial state to a thermal runaway condition. Indeed, the question arises at what temperature do these condensed fuels burst into flames, knowing that the presence of a passive coat greatly influences the process.For this study, a dedicated set-up has been improved. It consists of an electrodynamic levitator in which a single particle, trapped by electrostatic forces, burns in a controlled atmosphere. A two-color ratio pyrometer has been specifically assembled with photomultipliers (PM) to obtain the time evolution of mean surface temperature. The PM signals are synchronised witha particle visualization device that is composed of a high-speed camera combined with a long-distance microscope. Subsequently, the temperature measurement of high temporal resolution can then be associated for the first time at a rate of 250 000 fps with the fast-apparent phenomenology of the pre-ignition processes. In addition, the spatial resolution of the visualization (1.92 μm/pix) allows the interpretation of the PM signals to be commented.

International audience; Evaluating lipid profiles in human tissues and biofluids is critical in identifying lipid metabolites in dysregulated metabolic pathways. Due to various chemical characteristics, single-run lipid analysis has not yet been documented. Such approach is essential for analysing pathology-related lipid metabolites. Age-Related Macular Degeneration (AMD), the leading cause of vision loss in western countries, is emblematic of this limitation. Several studies have identified alterations in individual lipids, but the majority are based on targeted approaches. In this study, we analyzed and identified approximately 500 lipid species in human biofluids (plasma and erythrocytes) and ocular tissues (retina and retinal pigment epithelium) using the complementarity of hydrophilic interaction liquid chromatography (HILIC) and reversed-phase chromatography (RPC), coupled to high-resolution mass spectrometry (HRMS). For that, lipids were extracted from human eyeglobes and blood from 10 subjects and lipidomic analysis was carried out through analysis in HILIC and RPC, alternately. Furthermore, we illustrate the advantages and disadvantages of both techniques for lipid characterization. RPC showed greater sensitivity in hydrophobicity-based lipid separation, detecting diglycerides (DAG), triglycerides (TAG), cholesterol (Chol), and cholesterol esters (CEs), whereas no signal of these molecules was obtained in HILIC. However, due to coelution, RPC was less effective in separating polar lipids like phospholipids, which were separated effectively in HILIC in both ionization modes. The complementary nature of these analytical approaches was essential for the detection and identification of lipid classes/subclasses, which can then provide distinct insights into lipid metabolism, a determinant of the pathophysiology of several diseases involving lipids, notably AMD.

International audience; The functioning of the nitrous oxide (N2O) reductase enzyme involved in the last step of denitrification is pH sensitive, with an optimum of 6.8. A solution to mitigate N2O emissions would be to bring soil pH close to neutrality by adding agricultural liming products (aglime). Nevertheless, the influence of aglime on the soil greenhouse gas (GHG) balance (CO2–N2O) is a subject of debate, particularly when considering the fate of the carbon (C) derived from carbonates. Our objective was to investigate the results of the effect of calcium carbonate (CaCO3) aglime on the CO2–N2O balance. Sixteen cylinders of undisturbed acidic soil were taken from a sandy loam profile and incubated at 20°C for 107 days in anaerobic conditions (water-filled pore space >60%). Eight limed treatment cylinders received 1.45 g of aglime on the soil surface (2 t NV ha−1) and 0.08 g of N (100 kg of N ha−1). Eight control treatment cylinders received only 0.08 g of N. N2O and CO2 fluxes were measured and converted into CO2 equivalents to perform a GHG balance calculation. Furthermore, soil and leachate properties were measured. Aglime application triggered a reduction of N2O emissions, probably due to an increase in soil pH at the beginning of the experiment, which would have led to the N2O reductase activation. High NO3--N content in the soil may inhibit the high N2O reduction potential in the limed treatment. CO2 emissions were unexpectedly lower in the limed treatment. Aglime addition did not enhance C mineralisation, which may be explained by the possible stabilisation of soil organic carbon. A significant 11.3% reduction of GHG emissions was observed in the limed treatment. Overall, our results show that a strategy of liming acidic agricultural soil could be implemented for its potential in GHG mitigation. Nevertheless, future in-depth research is necessary to better understand the fate of the C brought about by aglime.

International audience; Lidar, a remote sensing technique, is used by archaeologists to detect and map sites and analyze past landscapes. This paper is addressed to archaeologists and remote sensing specialists processing or analyzing lidar data, or using it within an archaeological research or heritage management project. This article presents the entire process, from acquisition to data interpretation, with a focus on the steps that influence the quality of results. The case studies presented focus on applications in forested environments.; Technique de télédétection laser, le lidar est utilisé en archéologie pour détecter, cartographier les sites et analyser les paysages anciens. Cet article s'adresse aux archéologues et aux géomaticiens chargés de monter un projet ou de traiter et analyser des données lidar. Il présente tout le processus, de l'acquisition à l'interprétation des données, avec un focus sur les étapes pouvant influencer la qualité des résultats et une approche centrée sur l'étude des milieux forestiers pour la recherche et la protection du patrimoine.

International audience; The integration of Airborne Laser Scanning (ALS) survey into archaeological research and cultural heritage management has substantially added to our knowledge of archaeological remains in forested areas, and is changing our understanding of how these landscapes functioned in the past. Further, the results of ALS-based surveys of woodlands can now potentially be incorporated into micro-regional and landscape scale studies which rely on survey data, making an important contribution to our understanding of settlement patterns and land use - but doing so requires us to recognize and manage a host of biases inherent in ALS-based survey data. While many types of archaeological remains manifest as micro-topography, several important classes of features commonly appear as standing remains. The identification of these remains is important for archaeological prospection surveys based on ALS data. Standing structures in mixed scenes with vegetation are not well addressed by standard classification approaches. In this paper we propose an approach to the identification of these structures in the point cloud based on multi-scale measures of roughness, and measures of local density and normal orientation. We demonstrate this approach using discrete-return ALS data collected in the Franche-Comté region of France.

Omega-3 (n-3) polyunsaturated fatty acids (PUFAs), particularly docosahexaenoic acid (DHA), are required for the structure and function of the retina. They could also help to prevent or delay the development of retinopathies. Given the accumulating evidence showing the role of gut microbiota in regulating retinal physiology and host lipid metabolism, we evaluated the potential of long-term dietary supplementation with the Gram-positive bacterium Lacticaseibacillus helveticus strain VEL12193 to modulate the retinal n-3 PUFA content. A set of complementary approaches was used to study the impact of such a supplementation on the gut microbiota and host lipid/fatty acid (FA) metabolism. L. helveticus-supplementation was associated with a decrease in retinal saturated FAs (SFAs) and monounsaturated FAs (MUFAs) as well as an increase in retinal n-3 and omega-6 (n-6) PUFAs. Interestingly, supplementation with L. helveticus enriched the retina in C22:5n-3 (docosapentaenoic acid, DPA), C22:6n-3 (DHA), C18:2n-6 (linoleic acid, LA) and C20:3n-6 (dihomo gamma-linolenic acid, DGLA). Long-term consumption of L. helveticus also modulated gut microbiota composition and some changes in OTUs abundance correlated with the retinal FA content. This study provides a proof of concept that targeting the gut microbiota could be an effective strategy to modulate the retinal FA content, including that of protective n-3 PUFAs, thus opening paths for the design of novel preventive and/or therapeutical strategies for retinopathies.

International audience; Iron oxide nanoparticles (IONPs) are a promising material for the remediation of trace elements which are a significant source of soil pollution. Thus, as part of improving phytoremediation processes, the addition of IONPs to soil was tested in this study. A long-term experiment was performed in pot to assess the potential of magnetite (Fe3O4) nanoparticles (NPsMagn) to modify lead (Pb) availability to sunflower (Helianthus annuus) and its behavior in a water-soil-plant system under repeated water-deficiency stress. Plants were grown either in control soil, Pb polluted soil (final added lead 375 mg kg-1), Pb polluted soil containing 1 % dry weight NPsMagn or Pb polluted soil containing 1 % dry weight micro-sized magnetite for 90 days. Pb polluted soil and Pb treated soil containing NPsMagn do not affect plant growth but NPsMagn allow reduced oxidative impact as a decrease in lipid peroxidation was observed in their presence. Magnetic susceptibility measurements and Fe content in sunflower plants and leachates suggest that NPsMagn penetrate the roots but are not dispersed in soil solution. In addition, Pb content increased by 102 % and 22 % respectively in leaves and stems of plants treated with NPsMagn. Based on Pb content in soil solutions, NPsMagn decrease Pb in leachate by 50 %. During water stress periods, NPsMagn significantly improve water retention in soil and relative water content in plants. As a result of this, NPsMagn improve Pb availability and accumulation in sunflower plants in TEs contaminated soils unfavorable to plant growth. This study also highlights favorable effects of NPsMagn on Pb stabilization into soil, reducing their loss in leachates and on plant tolerance during water stress periods.

This article presents the measurement and analysis of the influence of velocity on the quasi-static deflections of industrial manipulators of three different manufacturers. Quasi-static deflection refers to the deflection of the end effector position of articulated robots during movement at low velocity along a predefined trajectory. Based on earlier reported observations by the authors, there exists a difference in the static and quasi-static deflections considering the same points along a trajectory. This work investigates this difference to assess the applicability of robotic compliance calibration at low velocities. For this assessment, the deflections of three industrial articulated robots were measured at different speeds and loads. Considering the similarity among the robot models used in this investigation, this work also elaborates on the potential influence of the measurement procedure on the measured deflections and its implications for the compliance calibration of articulated robots. For all industrial articulated robots in this investigation, the quasi-static deflections are significantly larger than the static ones but similar in trend. Additionally, the magnitude of the quasi-static deflections presents a proportional relationship to the Cartesian velocity.

International audience; The Okavango Delta in North Botswana is a hot-spot of biodiversity within the semi-arid central part of the South African plateau. This endorheic ecosystem is highly dependent on the annual flood that brings freshwater from the highlands of Angola to the North. However, in many places, the groundwater of the Delta is saline and contains very high concentrations of metal and metalloid elements, making it toxic to the flora and fauna. These saline waters have been largely studied and their formation is generally explained through evaporation and evapotranspiration processes. However, no studies have investigated the geochemical composition of the sediments that host the aquifers. Here, we provide a complete sedimentological and geochemical investigation (major, traces and rare earth elements, carbon and oxygen stable isotopes ratios, Sr and Nd isotope ratios) of the various geomorphological and ecological compartments that form the landscape of the SW Okavango Delta. We demonstrate that the non-connected underground aquifer is capped by a clay layer corresponding to a major event of dust deposition from the Makgadikgadi pan. We suggest that this aquifer may extend outside the island, below the floodplain and that the hydrological structure of the Nxaraga area is indeed composed of two non-connected aquifers of different origins. Challenging the model based on evaporation and evapotranspiration, we propose that the composition of that allochtonous clay and the in situ reactions between sediment, water and organic matter in a confined aquifer explain the geochemical enrichment of the water.

International audience; Emission of colloids from treatment wetlands solid deposit (SD) may affect the speciation, toxicity and transfer of organic and inorganic pollutants, thereby controlling the associated environmental risks. This study investigated the nature of the colloids and their influence on the leaching of major and trace elements over a wide range of pH between 2 and 12. Results evidenced the mobilization of high quantity of organic carbon leached from the SD and Al-Fe colloidal minerals embedded by large organic molecules. Based on their varying affinity for the different colloidal phases, three groups of chemical species were established: (i) elements with low affinity for colloidal phases, mainly released in truly dissolved fraction (30 kDa), preferentially associated to organic colloids (Li, Ca, Mg, Sr, Ba, Mn, Zn) or to mineral colloids (Pb, Cr, Sc, Y); and (iii) element with high affinity for large and truly dissolved organic molecules (Cu, Co, Cd, Ni). Differences observed in the partitioning of elements can be attributed to variations in the pH/Eh of the solutions, the nature of the colloidal phases, and the ionic properties of the considered elements. Small pH variations were found to modify drastically the speciation of the elements solubilized with potential effect on their (bio)availability. Results obtained on this study can be used to enhance wastewater treatment through constructed wetland process and improve recovery technics applied on solid deposits (agriculture, compounds extraction…).

In insects such as Drosophila melanogaster, flight guidance is based upon converging sensory information provided by several modalities including chemoperception. Drosophila flies are particularly attracted by complex odours combining volatile molecules from yeast, pheromones and microbe-metabolized food. Based on a recent study revealing that adult male courtship behaviour can be affected by early preimaginal exposure to maternally-transmitted egg factors, we wondered whether a similar exposure could affect free-flight odour tracking in flies of both sexes? Our main experiment consisted to test, in a wind tunnel, flies differently conditioned during preimaginal development. Each fly was presented to a dual choice of food labelled by groups of D. melanogaster or D. simulans flies of each sex. The combined effect of food with the cis-vaccenyl acetate pheromone (cVA), involved in aggregation behaviour, was also measured. In parallel, using the head-space method, we determined the "odorant" identity of the different labelled food tested. We also measured the antennal electrophysiological response to cVA in females and males resulting of the different preimaginal conditioning procedures. Our data indicate that flies differently modulated their flight response (take off, flight duration, food landing and preference), according to sex, conditioning and food choice. Our head-space analysis revealed that many food-derived volatile molecules diverged between sexes and species. Antennal responses to cVA showed a clear sex specific variation for conditioned flies, but not for control flies. In summary, our study indicates that preimaginal conditioning can affect Drosophila free flight behaviour in a sex specific manner.

International audience; New services with low-latency (LL) requirements are one of the major challenges for the envisioned Internet. Many optimizations targeting the latency reduction have been proposed, and among them, jointly rearchitecting congestion control and active queue management (AQM) has been particularly considered. In this effort, the L4S (Low Latency, Low Loss and Scalable Throughput) proposal aims at allowing both Classic and LL traffic to cohabit within a single node architecture. Although this architecture sounds promising for latency improvement, it can be exploited by an attacker to perform malicious actions whose purposes are to defeat its LL feature and consequently make their supported applications unusable. In this paper, we exploit different vulnerabilities of L4S which are the root of possible attacks and we show that application-layer protocols such as QUIC can easily be hacked in order to exploit the over-sensitivity of those new services to network variations. By implementing such undesirable flows in a real testbed and characterizing how they impact the proper delivery of LL flows, we demonstrate their reality and give insights for research directions on their detection.; De nouveaux services avec des exigences de faible latence constituent un des défis majeurs de l'Internet envisagé pour le futur. Beaucoup d'optimisations ciblant la latence ont été proposés, et parmi elles, la ré-architecture conjointe du contrôle de congestion avec la gestion active des files d'attentes a été particulièrement considéré. Dans cette optique, la proposition L4S (Low Latency, Low Loss and Scalable Throughput) vise à permettre la coexistence entre du trafic classique et du trafic faible latence au sein du même noeud réseau. Bien que cette architecture semble prometteuse pour l'amélioration de la latence, elle peut être exploitée par un attaquant réalisant des actions malicieuses ayant pour but de déjouer la garantie de faible latence, rendant de fait les services associés instables.Dans cet article, nous exploitons différentes vulnérabilités de L4S qui sont au coeur des attaques possibles et nous montrons que des protocoles de niveau applicatif tel que QUIC peuvent être facilement détournés dans le but d'exploiter l'hypersensibilité de ces nouveaux services aux variations réseaux. En implémentant de tels flux indésirables dans un banc de tests réaliste, et en caractérisant de quelle manière ils impactent la cadence de livraison des paquets des flux faibles latence, nous démontrons leur réalité et donnons des pistes de recherche pour leur détection.

International audience; Archaeologists have long considered intervisibility essential to understanding settlement patterns and landscape structure. The idea of intervisibility as a driver stems from the premise that, across epochs and cultures, (in)visibility is manipulated for communication, control and sometimes defense. For these reasons a broad suite of viewshed analyses were explored by archaeologists, primarily using GIS, from the 1980s.Many of these studies suggest that vegetation plays an important role in blocking, altering, and framing sightlines, but these suggestions remain relatively unexplored. The increasing availability of airborne laser scanning (ALS) datasets invites us to revisit these propositions. ALS data allows us to consider -with relative ease- multiple vegetation scenarios in which we vary spatial distributions and canopy structure to understand potential impacts on specific visual networks.The approach illustrated in this paper employs ‘rapid initial visual assessment’ of the elements of intervisibility analyses. Multiple 3D scenes are built using sightline vectors, DTMs, and vegetation models. These scenes allow us to immediately understand the impact of terrain and different vegetation states. This rapid exploratory protocol lets us establish a generalized chronology of the changes in extents of woodlands based on presumed or known visual networks. Because calculations are not computationally expensive, quickly modeling many scenarios is practical- opening the possibility of new approaches to visual networks.In this paper our approach is demonstrated use the ‘ceinture de fortifications’ constructed around Besançon in 19th century. Because the state of forest at the time of construction, and the intentions of the architects to create a visual network are well documented, the ceinture provides an ideal case study. We then consider the visual dynamics of two castles and a citadel, constructed and active in the Medieval and Early Modern periods, with reference to historical evidence for competition and cooperation between their respective communities.

International audience; Bimetallic layered double oxide (LDO) NiM (M = Cr, Fe) catalysts with nominal compositions of Ni/M = 2 or 3 were tailored from layered double hydroxides (LDH) using a coprecipitation method to investigate the effects of the trivalent metal (Cr or Fe) and the amount of Ni species on the structural, textural, reducibility, and catalytic properties for CH4/CO2 reforming. The solids before (LDH) and after (LDO) thermal treatment at 500 °C were characterized using TGA-TD-SM, HT-XRD, XRD, Raman, and IR-ATR spectroscopies; N2 physical adsorption; XPS; and H2-TPR. According to the XRD and Raman analysis, a hydrotalcite structure was present at room temperature and stable up to 250 °C. The interlayer space decreased when the temperature increased, with a lattice parameter and interlayer space of 3.018 Å and 7.017 Å, respectively. The solids fully decomposed into oxide after calcination at 500 °C. NiO and spinel phases (NiM2O4, M = Cr or Fe) were observed in the NiM (M = Cr, Fe) catalysts, and Cr2O3 was detected in the case of NiCr. The NiFe catalysts show low activity and selectivity for DRM in the temperature range explored. In contrast, the chromium compound demonstrated interesting CH4 and CO2 conversions and generally excellent H2 selectivity at low reaction temperatures. CH4 and CO2 conversions of 18–20% with H2/CO of approx. 0.7 could be reached at temperatures as low as 500 °C, but transient behavior and deactivation were observed at higher temperatures or long reaction times. The excellent activity observed during this transient sequence was attributed to the stabilization of the metallic Ni particles formed during the reduction of the NiO phase due to the presence of NiCr2O4, opening the path for the use of these materials in periodic or looping processes for methane reforming at low temperature.; Des catalyseurs bimétalliques oxyde double lamellaire (LDO) NiM (M = Cr, Fe) avec des compositions nominales de Ni/M = 2 ou 3 ont été fabriqués à partir d'hydroxydes doubles lamellaires (LDH) en utilisant une méthode de coprécipitation pour étudier les effets du métal trivalent (Cr ou Fe) et de la quantité d'espèces de Ni sur la structure, la texture, la réductibilité et les propriétés catalytiques pour le reformage de CH4/CO2. Les solides avant (LDH) et après (LDO) traitement thermique à 500 °C ont été caractérisés par des spectroscopies TGA-TD-SM, HT-XRD, XRD, Raman, et IR-ATR ; adsorption physique de N2 ; XPS ; et H2-TPR. Selon l'analyse XRD et Raman, une structure hydrotalcite était présente à la température ambiante et stable jusqu'à 250 °C. L'espace intercouche diminue lorsque la température augmente, avec un paramètre de réseau et un espace intercouche de 3,018 Å et 7,017 Å, respectivement. Les solides se sont entièrement décomposés en oxyde après calcination à 500 °C. Des phases NiO et spinelles (NiM2O4, M = Cr ou Fe) ont été observées dans les catalyseurs NiM (M = Cr, Fe), et Cr2O3 a été détecté dans le cas de NiCr. Les catalyseurs NiFe présentent une faible activité et sélectivité pour le DRM dans la gamme de température explorée. En revanche, le composé de chrome a montré des conversions intéressantes de CH4 et de CO2 et une sélectivité généralement excellente pour H2 à des températures de réaction basses. Des conversions de CH4 et de CO2 de 18 à 20 % avec H2/CO d'environ 0,7 ont pu être atteintes à des températures aussi basses que 500 °C, mais un comportement transitoire et une désactivation ont été observés à des températures plus élevées ou à des temps de réaction longs. L'excellente activité observée pendant cette séquence transitoire a été attribuée à la stabilisation des particules métalliques de Ni formées pendant la réduction de la phase NiO en raison de la présence de NiCr2O4, ouvrant la voie à l'utilisation de ces matériaux dans des processus périodiques ou en boucle pour le reformage du méthane à basse température.

International audience; This report focuses particularly on liquid crystals display (LCD) panels because they represent a significant amount of all WEEE collected. Technologies involving liquid crystals (LCs) have enjoyed considerable success since the 1970s in all fields of LC displays (LCDs). This currently provokes the problem of waste generated by such equipment. Based on current statistical data, the LC amount represents approximately 1.3 g for a 35-inch diameter LCD panel unit possessing a total weight of 15 kg. In France, a recent study revealed LCD waste to represent an average of 5.6 panels per household. This represents an important quantity of LCs, which are generally destroyed by incineration or washed out with detergents during the recycling processes of end-of-life (EOL) LCDs. Hence, the aim of this study is to show that it is possible to remove LC molecules from EOL-LCD panels with the goal of valorizing them in new sectors. EOL-LCD panels have undergone various stages of dismantling, chemical treatments and characterization. The first stage of manual dismantling enables the elimination of the remaining physical components of the panels to process LC molecules only, sandwiched between the two glass plates. Mechanical treatment by scraping allows us to obtain a concentrate of LCs. The results obtained from chemical and physical techniques show that these molecules retain the characteristics essential for their operation in the field of optical and electro-optical devices. As the use of LCD surfaces continues to rise significantly, the amounts and economic stakes are huge, fully justifying the development of an LC recovery process for used panels. Many potential uses have been identified for these LC molecules: in new flat LCD panels after purification of the LCs concentrate, in PDLC systems, as lubricants or in thermal applications.; Ce rapport se concentre particulièrement sur les écrans à cristaux liquides (LCD) car ils représentent une quantité importante de tous les DEEE collectés. Les technologies impliquant des cristaux liquides (LC) ont connu un succès considérable depuis les années 1970 dans tous les domaines des écrans LC (LCD). Ceci pose actuellement le problème des déchets générés par de tels équipements. Sur la base des données statistiques actuelles, la quantité de LC représente environ 1,3 g pour une unité de panneau LCD de 35 pouces de diamètre possédant un poids total de 15 kg. En France, une étude récente révèle que les déchets LCD représentent en moyenne 5,6 panneaux par foyer. Cela représente une quantité importante de LCD, qui sont généralement détruits par incinération ou lavés avec des détergents lors des processus de recyclage des LCD en fin de vie (EOL). Ainsi, le but de cette étude est de montrer qu'il est possible de retirer des molécules LC des panneaux EOL-LCD dans le but de les valoriser dans de nouveaux secteurs. Les panneaux EOL-LCD ont subi différentes étapes de démantèlement, de traitements chimiques et de caractérisation. La première étape de démontage manuel permet d'éliminer les composants physiques restants des panneaux pour ne traiter que les molécules LC, prises en sandwich entre les deux plaques de verre. Le traitement mécanique par grattage permet d'obtenir un concentré de CL. Les résultats obtenus à partir de techniques chimiques et physiques montrent que ces molécules conservent les caractéristiques essentielles à leur fonctionnement dans le domaine des dispositifs optiques et électro-optiques. Alors que l'utilisation des surfaces LCD ne cesse d'augmenter de manière significative, les montants et les enjeux économiques sont énormes, justifiant pleinement le développement d'un procédé de valorisation LC des dalles usagées. De nombreuses utilisations potentielles ont été identifiées pour ces molécules LC : dans de nouveaux écrans LCD plats après purification du concentré de LC, dans des systèmes PDLC, comme lubrifiants ou dans des applications thermiques.

International audience; "Mafate Micro Grid" is a research project funded by the European Regional Development Fund and held by a partnership between the PIMENT Laboratory of the Reunion Island University and the SIDELEC Reunion. The main purpose of the project is to develop and improve smart grid concept in Reunion Island. Mafate is a landlocked area non-connected to the main electrical grid. A major stake for local authorities is to electrify about 300 homes by means of solar microgrid installations. Our case study provides an actual Energy Management System application for 3 homes in Mafate, aiming to maximize the use of photovoltaic energy and to prolong battery life. The project is carried out closely with three Mafate homes, as a human-machine interface is installed in each house. This work is a preliminary approach to evaluate theoretically the effectiveness of a Demand Side Management process depending on the users' acceptability. Results show the Energy Management System reduces energy wastes and increases the solar energy effectively used, provided users follow the given advice.

Doctoral

International audience; Performative speech synthesis is a new avenue for expressive speech and singing analysis andsynthesis. At the confluence between new interfaces for musical expression, voice signal processingand acoustic phonetics, two vocal instruments are presented. Cantor Digitalis, a formant synthesizerusing a spectral glottal model, is controlled using bimanual gestures on a graphic tablet. Voks is basedon sampling and vocoding. It is controlled by bimanual gestures (graphic tablet or theremin) andbiphasic syllabic sequencing. Prosodic units and their organization for vocal instruments are discussedalong three lines: chironomic stylization of intonation and vocal effort, biphasic syllabic rhythmcontrol. Musical, pedagogical and clinical applications of this new organology of voice are discussed.; La synthèse vocale performative offre une nouvelle approche pour l’analyse et la synthèse de la paroleexpressive et du chant. Deux instruments vocaux, à la confluence entre nouvelles interfaces pourl’expression musicale, traitement du signal vocal et phonétique acoustique, sont présentés. CantorDigitalis est un synthétiseur à formants muni d’un modèle spectral de la source glottique, piloté pardes gestes bimanuels sur une surface tactile et un stylet. Voks est un vocodeur piloté par des gestesbimanuels, sur une surface tactile et un stylet, ou par un thérémine, augmenté d’un contrôle biphasiquedu séquencement syllabique. Les unités prosodiques, leur organisation et leur contrôle pour laconstruction des instruments vocaux sont discutés suivant trois lignes : la stylisation chironomique del’intonation et de l’effort vocal, le contrôle biphasique du rythme syllabique. La conclusion évoqueles applications musicales, pédagogiques, voire cliniques de cette nouvelle organologie de la voix.

Anopheles darlingi is a major vector of both Plasmodium falciparum and Plasmodium vivax in South and Central America. However, vector competence and physiology of this mosquito species have been scarcely studied due to difficulties in rearing it in the laboratory. Here, we report the successful establishment of a robust colony, from mosquito collection in French Guiana. We describe our mosquito colonization procedure with relevant information on environmental conditions, mating ability, larval development and survival, recorded over the first six critical generations. Experimental infection showed that our An. darlingi colony has a moderate permissiveness to in vitro produced gametocytes of the P. falciparum NF54 strain originating from Africa. This colony, that has reached its 20th generation, will allow further characterization of An. darlingi life-history traits and of Plasmodium-mosquito interactions with South American malaria parasites.

International audience; Background and aims: Smoking may lead to premature ageing, but the impact on the cardiovascular system and circulating proteins needs further investigation. In the present study, we aim to understand the impact of smoking on heart and vessels and circulating biomarkers of multiple domains including cardiovascular damage, premature ageing and cancer-related pathways.Methods: The STANISLAS Cohort is a longitudinal familial cohort with detailed cardiovascular examination and biomarker assessment. This study included all the participants enrolled in the fourth visit of the STANISLAS Cohort for whom information on smoking habits was available (n = 1696). We assessed pulse wave velocity, intima-media thickness, echocardiographic parameters and a total of 460 proteins to study the association of circulating plasma proteins with smoking status (never vs. past vs. current smoking) while adjusting for potential confounders.Results: Current smokers were approximately 18 years younger but had higher left ventricular mass index (LVMi) and similar pulse wave velocity (PWV), carotid intima media thickness (cIMT), frequency of hypertension, diabetes and carotid plaques compared to the much older never smokers. After multivariate selection, 25 proteins were independently associated with current or past smoking. Current smoking was strongly associated with higher levels of EDIL-3, CCL11, TNFSF13B, KIT, and lower levels of IL-12B and PLTP (p < 0.0001) while past smoking was associated with FGF-21, CHIT1, and lower levels of CXCL10, IL1RL2 and RAGE (p < 0.01).Conclusions: Current smoking is associated with signs of early onset of cardiovascular ageing and protein biomarkers that regulate inflammation, endothelial function, metabolism, oncological processes and apoptosis.

International audience; Size-effect in concrete and other quasi-brittle materials defines the relation between the nominal strength and structural size when material fractures. The main cause of size-effect is the so-called energetic size-effect which results from the release of the stored energy in the structure into the fracture front. In quasi-brittle materials and in contrast to brittle materials, the size of the fracture process zone is non-negligible compared to the structural size. As a consequence, the resulting size-effect law is non-linear and deviates from the response predicted by linear elastic fracture mechanics. In order to simulate the size-effect, one needs to rely on numerical modeling to describe the formation, development and propagation of the fracture process zone. Although a number of models have been proposed over the years, it transpires that a correct description of the fracture and size-effect which accounts for boundary effects and varying structural geometry remains challenging. In this study, the Lattice Discrete Particle Model (LDPM) is proposed to investigate the effects of structural dimension and geometry on the nominal strength and fracturing process in concrete. LDPM simulates concrete at the aggregate level and has shown superior capabilities in simulating complex cracking mechanisms thanks to the inherent discrete nature of the model. In order to evaluate concrete size-effect and provide a solid validation of LDPM, one of the most complete experimental data set available in the literature was considered and includes three-point bending tests on notched and unnotched beams. The model parameters were first calibrated on a single size notched beam under three-point bending and on the mechanical response under unconfined compression. LDPM was then used to perform blind predictions on the load-crack mouth opening displacement curves of different beam sizes and notch lengths. Splitting test results on cylinders were also predicted. The results show a very good agreement with the experimental data. The quality of the predictions was quantitatively assessed. In addition, a discussion on the fracturing process and dissipated energy is provided. Last but not least, the Universal Size-Effect Law proposed by Bažant and coworkers was used to estimate concrete fracture parameters based on experimental and numerical data.

National audience

International audience; Multimaterial optical fibers combining tellurite with chalcogenide glasses and featuring thin polymer structures are fabricated via the thermal drawing process. It is demonstrated that micrometric polyethersulfone films can be embedded within larger elongated tellurite/chalcogenide glass architectures. Taking advantage of the strong chemical reactivity contrasts which exist in the considered fiber geometries, a quasi-exposed-core waveguide is obtained by selective etching of the glass cladding. The potential of the postprocessed fiber structure is then assessed through evanescent-wave probing of liquids and numerical investigations are carried out to establish the device performances as function of selected optogeometric parameters. Those results open the way for the development of evolutive photonic objects benefiting from postdrawing processing of multimaterial fibers.

International audience; In this study, water vapor sorption, desorption properties and tensile mechanical properties of four cellulosic fibers, cotton (C), flax (F), viscose (V) and cellulose acetate (CA), were determined. The sorption and desorption isotherms were modeled using the Park model, which allowed an accurate fitting on the whole range of water activity. This model corresponds to a multi-sorption mode dividing in three sorption modes: Langmuir sorption, Henry’s law and water clustering. Park’s parameters were compared for the sorption and desorption isotherms for each fiber. Regardless of the fiber, differences between sorption and desorption were obtained only for the Henry sorption. The obtained sorption properties were correlated to the accessibility and the amount of sorption sites and also to the crystallinity level of the fibers. It was found that V exhibited the highest water sorption capacity due to a higher hydroxyl groups accessibility and a low amorphous fraction, followed by F, C and CA. Results from tensile tests demonstrated that F and C fibers were more rigid, more resistant and less ductile than CA and V fibers due to a difference of microstructure of the fibers. Finally, the presence of water-sorbed molecules led to a decrease in tensile modulus due to plasticization phenomenon.

International audience

National audience; Monde marin d’une grande diversité, la « Réserve de biosphère des îles et de la mer d’Iroise » se caractérise par la densité de ses habitats naturels et la productivité exceptionnelle de ses eaux. Balayée par la houle et les courants, elle constitue une zone refuge pour les espèces animales et végétales, dont les plus rares ou menacées sont désormais protégées. Tirant profit de ces richesses environnementales, l’Homme a marqué de son empreinte les paysages de l’Iroise. Tandis que de profondes mutations affectent aujourd’hui les populations insulaires, les pressions qui pèsent sur la biodiversité imposent d’adopter un nouveau rapport à l’environnement. Tel est l’objectif que poursuivent le Parc naturel régional d’Armorique et le Parc naturel marin d’Iroise depuis leur création. Cette bonne cohabitation de l’Homme et de ses ressources a élevé ce territoire au rang de « réserve de biosphère » par l’Unesco dès 1988. Pour les chercheurs, il est aussi un laboratoire à ciel ouvert. Etudier son « socio-écosystème » permet d’en dessiner la trajectoire et de proposer les solutions de demain dans un contexte de changement global.Travail collectif, cet atlas abondamment illustré fait un état des savoirs sur le sujet et invite à une découverte passionnante. Il montre combien la diversité est constitutive du vivant et pourquoi sa conservation est si importante pour les communautés humaines.

International audience; For several decades, plastic has been a global threat in terms of pollution. Plastic polymers, when introduce in the aquatic environment, are exposed to fragmentation processes into microplastics (MPs) and nanoplastics (NPs) which could potentially interact with living organisms. The objective of this work was to study the effects of plastic particles representative of those found in the environment, on the marine mussels Mytilus edulis, under two exposure scenarii: in vivo and in vitro. Whole mussels or cultured hemocytes were exposed for 24 hours to NPs and MPs generated from macro-sized plastics collected in the field, but also to reference NPs, at concentrations found in the environment: 0.08, 10 μg and 100 μg.L-1. Results showed that immune response was only activated when mussels were exposed in vivo. However, cytotoxicity (hemocyte mortality) and genotoxicity (DNA damage) parameters were induced after both types of exposure, but in a dose-dependent manner after in vitro hemocyte exposure to all tested plastic conditions. These results indicate that in vitro approaches could be considered as potential predictors of in vivo exposures.

International audience; ncreasing concerns over water eutrophication due to agricultural phosphorus (P) loss have led to the development of indicators to assess the risk of P release from agricultural soils. Recently, a logarithmic equation linking the degree of phosphorus saturation (DPS) to the simple water-soluble P (WSP) content of soils has been proposed as a universal method to assess this risk based, however, mainly on the analysis of well-drained soils. Here, we studied the P sorption properties and DPS values of 69 hydromorphic soils from cultivated and uncultivated wetland zones located in Brittany, Western France, to test whether the method could also apply to poorly-drained soils. The bulk soil analysis showed that P contents of the studied hydromorphic soils were 30 to 80% higher than P contents normally found in Brittany soils, evidencing a possible P enrichment process. Adsorption isotherms revealed a surprisingly high variability in the P sorption properties as a function of the location of the soil (maximum P adsorption capacity ranging from 500 to 1850 mg kg-1), which is caused by variations in the phases controlling P sorption in soil (from clay to organic matter and/or iron and aluminum oxides, depending on the soil location). Distinct relationships between DPS and WSP values were also obtained depending on the location of the soils. The obtained DPS vs. WSP relationships showed that the P saturation threshold above which the risk of dissolved P release increases markedly is 30% lower on average for hydromorphic soils than for well-drained soils. Hydromorphic soils appear to be more at risk of releasing dissolved P at the same DPS values than well-drained soils. The present study indicates an underestimation of the P release risk from hydromorphic soils by the existing method developed for well-drained soils and calls for the development of specific risk assessment tools for hydromorphic soils, especially given on the strong spatial heterogeneity of their P sorption properties

Obtaining accurate droplet temperature is essential to study heat and mass transfers in a wide range of spray applications such as spray cooling and spray combustion. A novel measurement technique based on the fluorescence lifetime is developed to tackle the challenge of measuring the droplet temperature in sprays. Similarly, to the intensity of the fluorescence signal, the fluorescence lifetime can vary with the temperature for some specific organic dyes, such as rhodamine B and kiton red. In the past, applications of laser-induced fluorescence (LIF) to the measurement of the temperature in sprays have been based exclusively on the fluorescence intensity by using intensity ratios of the signal detected by two or three photodetectors (PMTs, Cameras) operating at different spectral regions. Nonetheless, this approach is not straightforward, and corrections are usually required in dense sprays to mitigate some biases, which are arising in particular from the out-of-field fluorescence and multiple light scattering by the droplets. In contrast, measuring the fluorescence lifetime makes use of only a single detection spectral band and provides an absolute measurement unlike intensity-based measurements, which are always relative. In the present study, the time-correlated single-photon counting (TCSPC) is applied for the first time to measure the lifetime of the fluorescence emitted by droplets in a spray. The measurement technique provides the mean temperature of the liquid phase. No evidence of measurement biases could be pointed out during the tests performed at different injection conditions. Besides, a very high signal-to-noise ratio could be achieved even at a relatively far distance from the injection nozzle, resulting in an absolute error on the measured temperature that typically does not exceed ± 1 °C.

International audience; The very rapid development of vertical flow constructed wetlands (VFCW) in Europe and throughout the world has induced a growing concern on the conditions of management of their surface sludge deposits (SD). The leaching of organic components from SD was explored in this study with respect to their potential impact on biochemical oxygen demand (BOD) and their role as complexing agents in the release of trace contaminants. The aromaticity and molecular size of leached organic compounds was investigated over a large range of pHs. Experimental results showed that the pH of the leaching aqueous solution influenced the concentration and characteristics of leached OC. Around the natural pH of SD aqueous suspensions (6 to 8), truly dissolved organics (8), large organic colloids (>30 kDa) were found predominant, exhibiting a low aromaticity growing with pH. Under acidic conditions (pH

International audience; Cadmium (Cd) isotopes are known to fractionate during complexation with various environmentally relevant surfaces and ligands. Our results, which were obtained using (i) batch experiments at different Cd concentrations, ionic strengths, and pH values, (ii) modeling, and (iii) infrared and X-ray absorption spectroscopies, highlight the preferential enrichment of light Cd isotopes bound to humic acid (HA), leaving the heavier Cd pool preferentially in the solution (Δ114/110CdHA-Cd(aq) of -0.15 ± 0.01‰). At high ionic strengths, Cd isotope fractionation mainly depends on its complexation with carboxylic sites. Outer-sphere complexation occurs at equilibrium together with inner-sphere complexation as well as with the change of the first Cd coordination and its hydration complexes in solution. At low ionic strengths, non-specific Cd binding induced by electrostatic attractions plays a dominant role and promotes Cd isotope fractionation during complexation. This significant outcome elucidates the mechanisms involved in HA-Cd interactions. The results can be used during (i) fingerprinting the available Cd in soil solution after its complexation with solid or soluble natural organic matter and (ii) evaluate the contribution of Cd complexation with organic ligands and phytoplankton-derived debris vs. Cd assimilation by phytoplankton in seawater.

International audience; In the fight against climate change, the energy consuming building sector must also be taken into account to solve this problem. In this case thermal insulation of buildings using bio-based materials is an interesting solution. Therefore, the thermal performance of some materials of this type has been studied. The advantages of these natural materials of plant origin are multiple, biodegradable, low economic cost, renewable and readily available. The use of biobased materials is widespread in the building sector in order to replace conventional insulation materials with natural materials. Vegetable fibers are very important because they have good thermal behaviour and good insulating properties. The aim of using bio-sourced materials is in line with the logic of energy control and environmental protection, the approach is to make the inhabitants of the houses comfortable and reduce their energy consumption (energy efficiency). In this research we will present the results of studies carried out on the thermal conductivity of banana leaves, latan leaves, vetivers fibers, palm kernel fibers, sargassum, coconut leaves, sawdust and bulk sugarcane leaves. The study on thermal conductivity was carried out in two ways, on the one hand using the flash method, and on the other hand a so-called hot box experiment was carried out. We will discuss and highlight a number of influential factors such as moisture and air pockets present in the samples on the thermophysical properties of these materials, in particular thermal conductivity. Finally, the result of a thermal performance test of banana leaves on a roof in Haiti will also be presented in this work.

International audience; In this paper we study the generation and behavior of subharmonics in a bubbly liquid confined in an acoustic resonator, through numerical simulations carried out at finite-amplitude acoustic pressure. Several configurations in terms of resonator length and driving frequency are considered here. Our results show that these frequency components, created from a higher-frequency signal at the source (ultrasound), are due to the nonlinearity of the medium at high acoustic-pressure amplitude and to the configuration of the resonator (geometry and boundaries). We also show that they have an amplitude-threshold dependence, which is in concordance with the literature. The response of these subharmonics to different sequences of pressure amplitudes also reveals the hysteretic nature of the bubbly liquid.

International audience; Magnetite nanoparticles, commonly found in subsurface environments, are extensively used in various applications such as environmental remediation, catalysis, electronics and medicine. However, the oxidative transformation of magnetite (mixed-valent Fe-oxide) into maghemite (Fe(III)-oxide) that drastically affects magnetic, catalytic and redox properties of the mineral, is still poorly understood. In the present study, a thorough characterization of both particle core and surface of magnetite was performed to accurately assess the relationship between mineral composition and reactivity within the magnetite/maghemite core-shell structure. Previous work showed that X-ray absorption spectra (XAS) and X-ray magnetic circular dichroism (XMCD) can provide key insights into magnetite stoichiometry (R = Fe(II)/Fe(III)) of 10 nm sized particles, as compared to wet chemistry and X-ray diffraction (XRD). In the present study, XMCD signals have been used to further characterize the complex reactions involved in the magnetite/maghemite system upon oxidation and recharge processes, e.g. decreasing R from 0.5 to 0.1 using H2O2 or increasing from 0.1 to 0.5 through dissolved Fe2+ amendment. Indeed, surface recrystallization processes, induced by oxidation as well as Fe2+ diffusion into the solid phase and/or redistribution of electron equivalents between the aqueous solution and the magnetite bulk, led to decreased spin canting effects, altering XMCD signals. This study provides a fundamental understanding of the processes occurring in the magnetite/maghemite system upon the alteration of the redox conditions and offers a more accurate method for the determination of magnetite stoichiometry by XMCD.

International audience; Background and aims: Apolipoprotein (apo) C1 is a 6.6 kDa protein associated with HDL and VLDL. ApoC1 alters triglyceride clearance, and it also favors cholesterol accumulation in HDL, especially by inhibiting CETP in human plasma. Apart from studies in mice, which lack CETP, the impact of apoC1 on atherosclerosis in animal models expressing CETP, like in humans, is not known. This study aimed at determining the net effect of human apoC1 on atherosclerosis in rabbits, a species with naturally high CETP activity but with endogenous apoC1 without CETP inhibitory potential.Methods: Rabbits expressing a human apoC1 transgene (HuApoC1Tg) were generated and displayed significant amounts of human apoC1 in plasma.Results: After cholesterol feeding, atherosclerosis lesions were significantly less extensive (-22%, p < 0.05) and HDL displayed a reduced ability to serve as CETP substrates (-25%, p < 0.05) in HuApoC1Tg rabbits than in WT littermates. It was associated with rises in plasma HDL cholesterol level and PON-1 activity, and a decrease in the plasma level of the lipid oxidation markers 12(S)-HODE and 8(S)HETE. In chow-fed animals, the level of HDL-cholesterol was also significantly higher in HuApoC1Tg than in WT animals (0.83 ± 0.11 versus 0.73 ± 0.11 mmol/L, respectively, p < 0.05), and it was associated with significantly lower CETP activity (cholesteryl ester transfer rate, -10%, p < 0.05; specific CETP activity, -14%, p < 0.05).Conclusions: Constitutive expression of fully functional human apoC1 in transgenic rabbit attenuates atherosclerosis. It was found to relate, at least in part, to the inhibition of plasma CETP activity and to alterations in plasma HDL.

International audience; Context Nitrogen (N) and phosphorus (P) exports from rural landscapes can cause eutrophication of inland and coastal waters. Few studies have investigated the influence of the spatial configuration of nutrient sources-i.e. the spatial arrangement of agricultural fields in headwater catchments-on N and P exports. Objectives This study aimed to (1) assess the influence of the spatial configuration of nutrient sources on nitrate (NO3-) and total phosphorus (TP) exports at the catchment scale, and (2) investigate how relationships between landscape composition (% agricultural land-use) and landscape configuration vary depending on catchment size. Methods We analysed NO3- and TP in 19 headwaters (1-14 km(2), Western France) every two weeks for 17 months. The headwater catchments had similar soil types, climate, and farming systems but differed in landscape composition and spatial configuration. We developed a landscape configuration index (LCI) describing the spatial organisation of nutrient sources as a function of their hydrological distance to streams and flow accumulation zones. We calibrated the LCI's two parameters to maximise the rank correlation with median concentrations of TP and NO3-. Results We found that landscape composition controlled NO3- exports, whereas landscape configuration controlled TP exports. For a given landscape composition, landscape spatial configuration was highly heterogeneous at small scales (< 10 km(2)) but became homogeneous at larger scales (> 50 km(2)). Conclusions The spatial configuration of nutrient sources influences TP but not NO3- exports. An ideal placement of mitigation measures to limit diffuse TP export should consider both the hydrological distance to streams and flow accumulation zones.

The exosporium is the outermost spore layer of some Bacillus and Clostridium species and related organisms. It mediates interactions of spores with their environment, modulates spore adhesion and germination and could be implicated in pathogenesis. The exosporium is composed of a crystalline basal layer, formed mainly by the two cysteine-rich proteins CotY and ExsY, and surrounded by a glycoprotein hairy nap. The morphogenetic protein CotE is necessary for Bacillus cereus exosporium integrity, but how CotE directs exosporium assembly remains unknown. Here, we followed the localization of SNAP-tagged CotE, -CotY and -ExsY during B. cereus sporulation, using super-resolution fluorescence microscopy and evidenced interactions among these proteins. CotE, CotY and ExsY are present as complexes at all sporulation stages and follow a similar localization pattern during endospore formation that is reminiscent of the localization of Bacillus subtilis CotE. We show that B. cereus CotE drives the formation of one cap at both forespore poles by positioning CotY and then guides forespore encasement by ExsY, thereby promoting exosporium elongation. By these two actions, CotE ensures the formation of a complete exosporium. Importantly, we demonstrate that the assembly of the exosporium is not a unidirectional process as previously proposed but it is performed through the formation of two caps, as observed during B. subtilis coat morphogenesis. It appears that a general principle governs the assembly of the spore surface layers of Bacillaceae.IMPORTANCESpores of Bacillaceae are enveloped in a glycoprotein outermost layer. In the B. cereus group, encompassing the B. anthracis and B. cereus pathogens, this layer is easily recognizable by a characteristic balloon-like appearance separated from the underlying coat by an interspace. In spite of its importance for the environmental interactions of spores, including those with host cells, the mechanism of assembly of the exosporium is poorly understood. We used super-resolution fluorescence microscopy to directly visualize formation of the exosporium during sporulation of B. cereus and we studied the localization and interactions of proteins essential for exosporium morphogenesis. We discovered that these proteins form a morphogenetic scaf-fold, before a complete exosporium or coat are detectable. We describe how the different proteins localize to the scaffold and how they subsequently assemble around the spore and we present a model for the assembly of the exosporium.

This paper discusses the dynamic between digital tools and the actor’s ability to listen. It presents the results of the workshop Voices on Stage: An Approach to Ancient Greek Tragedy in the Digital Era (Athens, 2018) which confronts the actor to different layers of voice (direct, amplified, and synthetic). Through those experiments and their analysis, one will demonstrate how listening to synthetic voices can reinforce the actor’s sensibility to voice, stimulate his/her’s other senses and transform the act of listening into a tactile and visual experience., L'acteur et l'écoute augmentée: tissage sonore de voix autour des Bacchantes d'Euripide En s'appuyant sur une expérience pédagogique basée sur la confrontation des voix nonmédiatisée, amplifiée et synthétisée, lors du workshop Voices On Stage : An Approach to Ancient Greek Tragedy in the Digital Era (Athènes, 2018), cet article propose une réflexion sur la relation entre les technologies digitales et l'écoute de l'acteur. Il s'agit de démontrer que l'écoute de voix de synthèse-souvent mise en opposition aux voix "naturelles" ou "organiques"-peut paradoxalement constituer pour l'acteur une façon de renforcer son rapport sensible à la voix et de stimuler ses sens autrement., O ator e a escuta aumentada: tecido de vozes em As Bacantes de Eurípides Partindo de uma experiência artística e pedagógica baseada no encontro de vozes não midiatizadas, vozes amplificadas e vozes sintetizadas durante o workshop Voices on Stage: An Approach to Ancient Greek Tragedy in the Digital Era (Atenas, 2018), este artigo discute a relação entre as tecnologias digitais e a escuta do ator. O objetivo é demonstrar que as vozes sintetizadas-geralmente consideradas como o extremo oposto das vozes ditas "naturais" e "orgânicas"-pode paradoxalmente reforçar a relação sensível do ator com sua própria voz e estimular outros sentidos, tornando a escuta tátil e visual.

International audience; Amerindian and Maroon populations of French Guiana have been living in isolation for generations and sexual networks remained mostly endogamous. The present study aimed to describe the phylogeny of E6 and E7 sequences of the most common high-risk HPV genotypes in these regions, to ascertain the diversity of intra-type variants and describe evolutionary relationships. There were 106 women with at least one of HPV16, 18, 31, 52, 58, and 68 genotypes. The most clear-cut phylogenetic pattern was obtained for HPV18 and HPV58 for which the major branches were crisply divided between Amerindian villages on the Oyapock and Maroon villages on the Maroni. Such clustering was less clear for HPV31 and 52. For HPV16, there was also some evidence of clustering on the Oyapock with type A European viruses and on the Maroni with type B and C African viruses among Maroon women. HPV68 showed the largest sequence heterogeneity of the six genotypes at both nucleotide and amino acid levels and was restricted to Maroon women. The present results show that there were significant geographically based differences of E6 and E7 oncogenes. These differences were compatible with different ancestral virus populations and local virus evolution in a context of prolonged population isolation.