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Climate Change has already caused large losses on natural occurring ice in the last decades and continues to do so. Antarctica, the largest source of land ice, contains an equivalent of several tens of meters of sea water level rise, which is induced not only by melting but also by out flow into ice shelves, the floating tongues of glaciers. In the last decades with recorded longer melt seasons and warming water in Antarctica, ice shelves are thinning and breaking up. With that, speed up of shelf inflowing glaciers are recorded, highlighting the buttressing force ice shelves have on glaciers and therefore their importance to the Antarctic Ice Sheet.Many factors play a roll in the integrity of ice shelves, besides melting on the surface and from below, waves, tides and pressure imbalances at the calving front (buoyancy force) induce bending moments on short time scales.While ice is mainly studied as purely viscous, elastic or even plastic material. Certain ice shelf behaviour, like the tidal deformation near the grounding line or drainage of melt ponds, can only be sufficiently simulated with an viscoelastic model - representing the viscous thinning of ice as well as short term elastic bending deformations.Viscoelastic studies of ice so far have used commercial proprietary software, which require expensive licences and often lack inside in the used algorithms or flexibility to adapt the code as needed.In this thesis a viscoelastic model was developed in the open source FEM C++ environment Rheolef.; Le changement climatique a engendré des pertes considérables pour les glaces continentales au cours de ces dernières décennies et perdure toujours aujourd'hui. L'Antarctique, la plus grande réserve de glace naturelle recèle à lui seul l'équivalent d'une hausse potentielle du niveau marin mondial de plusieurs dizaines de m, laquelle résulte non seulement de la fonte mais aussi de l'écoulement de la glace au travers les plateformes flottantes des glaciers émissaires, les 'ice shelves'. Depuis les dernières décennies caractérisées par des saisons de fonte plus longues et un océan de plus en plus chaud les 'ice shelves' s'amincissent et se désintégrent plus facilement. Parallèlement, une accélération des glaciers nourrissant ces shelves s'observe, mettant en évidence leur caractère d'arc-boutant sur l'écoulement de la glace vers la mer et leur importance sur la calotte glaciaire Antarctique.De nombreux facteurs participent à la perte de cohésion des ice shelves. En plus de la fonte en surface et à la face inférieure, les vagues, les marrées ainsi que les différences de pression au niveau du front de vêlage induisent des moments de torsion à haute fréquence.La glace est généralement modélisée comme étant soit purement visqueuse, soit élastique voire même plastique, cependant, certains des comportements du shelf comme la déformation liée aux marrées près de la ligne d'échouage ou la purge des lacs de surface ne peuvent être correctement simulés qu'avec un modèle visco-élastique reproduisant à la fois l'amincissement visqueux de la glace et le flambage élastique à court terme de la plaque.Jusqu'à présent, les modélisations visco-élastiques de la glace ont fait appel à des codes commerciaux coûteux aux algorithmes figés et non adaptables aux spécificités du problème. Cette thèse propose le développement d'un modèle visco-élastique de la dynamique des shelves à l'aide de l'environnement 'open 'source' Finite Element Method C++ Rheolef.

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International audience; This paper studies wave influence on two horizontal axis tidal turbines from industrial partners : Sabella and Magallanes. The trials have been performed in a wave and current flume tank where upstream flow conditions have been monitored thanks to Laser Doppler Velocimetry. Mean velocity is computed withrotor disc integration of the velocity profile. Wave amplitude and orbital amplitude are computed thanks to least mean square method.A special attention has been paid to turbine immersion depth. Performance and blade root loads analysis highlight higher fluctuations when the turbine is close to the free surface.When a turbine is close to the free surface, the edgewise moment fluctuations can reach 100 % of the mean effort under combined wave and turbulence loading. Wave is responsible for half part of these fluctuations.; Dans ce papier est étudiée expérimentalement l’influence de la houle et du courant combinés sur le comportement de deux hydroliennes à axe horizontal pré-commerciales. Les essais sont réalisés dans un bassin à houle et courant où les conditions d’essais sont obtenues par vélocimétrie laser. La vitesse moyenne de l’écoulement est calculée par intégration sur le disque rotor. Les amplitudes de houle et les orbitales de vague sont déterminées par méthode des moindre carrés.Une attention particulière est apportée sur l’influence de la profondeur d’immersion des turbines. L’analyse des performances et des efforts sur les pales met en évidence une augmentation des fluctuations d’efforts avec la diminution de la profondeur.Le moment de mise en rotation en pied de pale sur une turbine subit des fluctuations allant jusqu’à 100 % de l’effort moyen sous l’effet de la houle et de la turbulence lorsque la turbine est proche de la surface libre. La houle est responsable de la moitié de cette fluctuation.

In discontinuous Galerkin spectral element methods (DGSEM), the two most common approaches to numerically integrate the terms of the weak form are either using Gauss-Legendre or Gauss-Lobatto quadratures. The former yields more accurate results but at a higher computational cost, so that a priori it is not clear whether one approach is more efficient that the other. In this paper, it is shown (theoretically for a particular case and numerically for the general case) that using Gauss-Lobatto quadrature for the convection matrix actually introduces a negligible error. In contrast, using Gauss-Lobatto quadratures for the evaluation of the jump term in the element faces introduces a sizeable error. This leads to the proposal of a new DG approach, where the convection matrix is evaluated using Gauss-Lobatto quadratures, whereas the face mass matrices are integrated using Gauss-Legendre quadratures. For elements with constant Jacobian and constant coefficients, a formal proof shows that no numerical integration error is actually introduced in the evaluation of the residual, even though both the mass and the convection matrices are not computed exactly with Gauss-Lobatto quadratures. For elements with non-constant Jacobian and/or non-constant coefficients, the impact of numerical integration error on the overall error is evaluated through a series of numerical tests, showing that this is also negligible. In addition, the computational cost associated to the matrix-vector products required to evaluate the residual is evaluated precisely for the different cases considered. The proposed approach is particularly attractive in the most general case, since the use of Gauss-Lobatto quadratures significantly speeds-up the evaluation of the residual.

International audience

International audience; This paper studies wave influence on two horizontal axis tidal turbines developed by industrial partners: Sabella and Magallanes Renovables. The trials are performed in a wave and current flume tank where upstream flow conditions are monitored thanks to Laser Doppler Velocimetry. Wave amplitude and orbital amplitude are computed thanks to least mean square method. The turbulence is analysed through its intensity and a power spectral density point of view. A special attention is paid to turbine immersion depth. Global torque and thrust are analyzed in the frequency domain thanks to power spectral density and magnitude square coherence. Wave generates a strong torque and thrust fluctuation level of the same order as the mean effort level. Both torque and thrust respond to wave at wave and twice the wave frequency for all turbines whatever the immersion.

International audience; Explosive activity preceding the ~40 ka Campanian Ignimbrite (CI) eruption in the Neapolitan volcanic area, Southern Italy, has long been speculated based on the occurrences of widespread tephra layers, with a Campanian geochemical signature, such as the C-22, X-5, and X-6, preserved in Mediterranean Marine Isotope Stage (MIS) 5 sedimentary records. However, previous studies of pre-CI pyroclastic units occurring in close proximity of the Neapolitan volcanoes, including Campi Flegrei, Somma-Vesuvius, Ischia and Procida islands, did not allow a conclusive identification of the near-source equivalents of these tephra markers. Here we present a comprehensive characterization of four pyroclastic units from the Campanian Plain, comprising major and trace element glass compositions, Sr[sbnd]Nd isotopes and 40Ar/39Ar dating. Our data allowed the identification of the medial equivalents of the MIS 5 tephra markers, including the widespread C-22, X-5, and X-6 tephra, and their assignment to previously undocumented Campi Flegrei activity between 109 and 92 ka. In addition to substantially extending Campi Flegrei explosive activity deeper in time, and thus providing the basis for a revaluation of its history, our findings provide new precise radioisotopic dating to better constrain the chronology of the millennial scale climatic oscillations of the MIS 5c-d in the Mediterranean area and possibly on a larger scale.

International audience; Precisely detecting solar Active Regions (AR) from multi-spectral images is a challenging task yet important in understanding solar activity and its influence on space weather. A main challenge comes from each modality capturing a different location of these 3D objects, as opposed to more traditional multi-spectral imaging scenarios where all image bands observe the same scene. We present a multi-task deep learning framework that exploits the dependencies between image bands to produce 3D AR detection where different image bands (and physical locations) each have their own set of results. We compare our detection method against baseline approaches for solar image analysis (multi-channel coronal hole detection, SPOCA for ARs (Verbeeck et al., 2013)) and a state-of-the-art deep learning method (Faster RCNN) and show enhanced performances in detecting ARs jointly from multiple bands.

International audience; The purpose of this study was to examine the association between young players’ perception of mother’s and father’s responsiveness with their self-esteem, anxiety (i.e., worry), and thriving (i.e., positive affect, vitality, and life satisfaction). In total, 314 male British rugby players with a mean age of 16.23 years (SD = 0.26) completed the study in two phases: n = 124 (first dataset), and n = 192 (second dataset). Participants trained on average 3.14 times/week (SD = 0.94) and had been involved in rugby for an average of 8.21 years (SD = 2.89). Participants completed questionnaires measuring perceived parental responsiveness (PPR) for their mother and father, self-esteem, worry about sport performance, and thriving indicators (i.e., positive affect, vitality, and life satisfaction). The results consistently indicated that participants’ perceptions of their mother’s and father’s responsiveness positively related to thriving, and negatively related to their worry about sport performance, mediated by their self-esteem. Overall, the study highlights the need for parents to be provided with insights into the value of being responsive to their child and being encouraged to regularly talk with their child regarding their needs and desires, and seeking to understand how their child perceives the support they currently receive.

Monte Carlo simulations are the numerical method of choice for the study of lattice field theories in a non-perturbative framework. Over the years, Monte Carlo methods in Lattice Field Theories have reached a level of maturity such that in several QCD applications they provide the most reliable predictions for the low-energy behaviour of the theory. However, for many interesting theories, a complex-valued action prevents the use of standard sampling techniques. This is generally known as the sign problem and is present if the Boltzmann weight associated with the field configurations is either non-positive or non-real. A class of models exhibiting this property are finite density theories. These are going to be our primary interest.In this work, we shall focus on the density of states approach to the sign problem. This is a numerical technique that enables us to use standard Monte Carlo techniques to evaluate the density of states relating to the imaginary part of the action. By doing this, the sign problem is reduced to a simpler one-dimensional oscillatory integral, amenable to standard deterministic quadrature methods.At the core of our implementation of the density of states method is the LLR algorithm. We will present the general implementation and recent developments regarding on the control of possible sources of bias. Then we will extend the current formulation to allow for the evaluation of generic observables. Both these topics will be supported by results from numerical studies of the relativistic Bose gas at finite density.Lastly, we will discuss the problem of applying this approach to fermionic models where the sign problem is generated by the complex-valued fermionic determinant. As a specific application, we will study the Thirring model in two different representations discussing the related challenges., Les simulations de Monte Carlo sont la méthode numérique de choix pour l'étude des théories des champs sur réseau dans un système non perturbatif. Au fil des ans, les méthodes de Monte Carlo dans les théories de champ sur réseau ont atteint un niveau de maturité tel que dans plusieurs applications QCD, elles fournissent les prédictions les plus fiables pour le comportement à basse énergie de la théorie. Cependant, pour de nombreuses théories intéressantes, une action à valeurs complexes empêche l'utilisation de techniques d'échantillonnage standard. Ceci est généralement connu sous le nom de problème de signe et est présent si le poids de Boltzmann associé aux configurations de champ est non positif ou non réel. Une classe de modèles présentant cette propriété sont les théories de densité finie. Celles-ci seront notre principal intérêt.Dans ce travail, nous nous concentrerons sur l'approche de la densité d'états au problème de signe. Il s'agit d'une technique numérique qui permet d'utiliser les techniques standards de Monte Carlo pour évaluer la densité d'états relatifs à la partie imaginaire de l'action. En faisant cela, le problème du signe est réduit à une intégrale oscillatoire unidimensionnelle plus simple, qui se prête aux méthodes de quadrature déterministes standard.Au cœur de notre implémentation de la méthode de la densité des états se trouve l'algorithme LLR. Nous présenterons la mise en œuvre générale et les développements récents concernant le contrôle des sources possibles de biais. Ensuite, nous étendrons la formulation actuelle pour permettre l'évaluation d'observables génériques. Ces deux sujets seront étayés par les résultats d'études numériques du gaz de Bose relativiste à densité finie.Enfin, nous discuterons du problème de l'application de cette approche aux modèles fermioniques où le problème des signes est généré par le déterminant fermionique à valeurs complexes. En tant qu'application spécifique, nous étudierons le modèle Thirring dans deux représentations différentes abordant les défis associés.

International audience

International audience; Fluoride-Ion Batteries (FIBs) have been recently proposed as a post-lithium-ion battery system. This review article presents recent progress of the synthesis and application aspects of the cathode, electrolyte, and anode materials for fluoride-ion batteries. In this respect, improvements in solid-state electrolytes for FIBs as well as liquid electrolytes will be discussed. Furthermore, the achievements regarding the development of cathode and anode materials will be considered. With the improvements made, the field is currently attracting a steady increase of interest, and we will discuss the potentials of this technology together with necessary future milestones to be achieved in order to develop FIBs for future energy storage.

Precisely localising solar Active Regions (AR) from multi-spectral images is a challenging but important task in understanding solar activity and its influence on space weather. A main challenge comes from each modality capturing a different location of the 3D objects, as opposed to typical multi-spectral imaging scenarios where all image bands observe the same scene. Thus, we refer to this special multi-spectral scenario as multi-layer. We present a multi-task deep learning framework that exploits the dependencies between image bands to produce 3D AR localisation (segmentation and detection) where different image bands (and physical locations) have their own set of results. Furthermore, to address the difficulty of producing dense AR annotations for training supervised machine learning (ML) algorithms, we adapt a training strategy based on weak labels (i.e. bounding boxes) in a recursive manner. We compare our detection and segmentation stages against baseline approaches for solar image analysis (multi-channel coronal hole detection, SPOCA for ARs) and state-of-the-art deep learning methods (Faster RCNN, U-Net). Additionally, both detection and segmentation stages are quantitatively validated on artificially created data of similar spatial configurations made from annotated multi-modal magnetic resonance images. Our framework achieves an average of 0.72 IoU (segmentation) and 0.90 F1 score (detection) across all modalities, comparing to the best performing baseline methods with scores of 0.53 and 0.58, respectively, on the artificial dataset, and 0.84 F1 score in the AR detection task comparing to baseline of 0.82 F1 score. Our segmentation results are qualitatively validated by an expert on real ARs.

International audience; Objective: The purpose of this study was to examine the influence of parental responsive support (observed) and perceived parental responsive support on athletes’ self-perceptions and thriving. Methods: Forty-one French-speaking Belgian individual sport athletes aged 12-15 years (M = 13.13, SD = 0.90) and one of their parent’s spent 10 minutes discussing three important athletes’ sport-related goals for the next season. The discussion was video-taped and coded to identify parents’ responsive support behaviors. After the discussion, athletes responded to a series of questionnaires measuring perceived parental responsiveness, self-efficacy, self-esteem, and thriving indicators (i.e., positive affect, vitality, life satisfaction, and health quality). Results: The results show that observed and perceived parental responsive support contributed to athletes’ proximal perceptions of self-efficacy. Both parental observed responsive support and athletes’ perceived parental responsiveness, mediated by athletes’ self-efficacy, were positively related to athlete’s self-esteem. Further, athletes’ perceived parental responsiveness was positively related with thriving while mediated in series by self-efficacy and self-esteem. Conclusion: Overall, it appears that parents’ responsive support (observed) and athletes’ perception of responsive support are associated with positive self-perceptions and optimal wellbeing in young athletes. This study demonstrates that parents can provide responsive support to their children in the sport context. These results add further weight to suggestions that sport organizations should actively include, rather than exclude, parents in their processes.

International audience; Scanning transmission electron microscopy experiments indicate that face-centered cubic (FCC) is the predominant ordered structure for Ag309 ± 7 nanoclusters, synthesized in vacuum. Historically, experiments do not present a consensus on the morphology at these sizes, whereas theoretical studies find the icosahedral symmetry for Ag309 and the decahedral shape for nearby sizes. We employ density functional theory calculations to rationalize these observations, considering both regular and defective Ag nanoparticles (281–321 atoms). The change of stability induced by the presence of defects, symmetry loss, and change of number of atoms is evaluated by the nanoparticle surface energy, which was measured previously. FCC and decahedral symmetries are found to be more favorable than icosahedral, consistent with our measurements of clusters protected from extended atmospheric exposure. In addition, an energy-free descriptor, surface atomic density, is proposed and qualitatively reproduces the surface energy data. Nonsymmetric and defective structures may be preferred over perfectly regular ones within a given size range.

In line with the latest innovations in the packaging field, this joint project aims at implementing new and innovative micro- and nanoparticles for the development of active and intelligent packaging solutions dedicated to food and medical packaging applications. More specifically, the project combines two major developments which both falls within the scope of active and intelligent packaging. In this work, a specific focus was given to the development of an antibacterial packaging solution and to the development of smart gas sensors. The antibacterial strategy developed was based on the combination of two active materials - silver nanowires and cellulose nanofibrils - to prepare antibacterial surfaces. The formulation as an ink and the deposition processing has been deeply studied for different surface deposition processes that include coatings or screen-printing. Results showed surfaces that display strong antibacterial activity both against Gram-positive and Gram-negative bacteria, but also interesting properties for active packaging applications such as a highly retained transparency or enhanced barrier properties. Regarding the second strategy, gas sensors have been prepared using a combination of Copper benzene-1,3,5-tricarboxylate Metal Organic Framework and carbon-graphene materials, deposited on flexible screen-printed electrodes. The easy-to-produce and optimized sensors exhibit good performances toward ammonia and toward humidity sensing, proving the versatility and the great potential of such solution to be adapted for different target applications. The results of this project lead to innovative solutions that can meet the challenges raised by the packaging industry., En lien avec les dernières innovations dans le domaine des emballages, ce projet collaboratif a pour but d’implémenter de nouveaux micro- et nanomatériaux innovants pour le développement d’emballages actifs et intelligents dans le domaine alimentaire et médical. Il se focalise en particulier sur deux stratégies : le développement d’emballages antibactériens d’un côté et de capteurs de gaz de l’autre. La première stratégie est donc dédiée à l’utilisation combinée de nanofils d’argent et de nanofibrilles de cellulose pour la production de surfaces antibactériennes. La formulation d’encres ainsi que les paramètres de dépôt ont été optimisés pour différent procédés tels que l’enduction ou l’impression sérigraphique. Une forte activité antibactérienne contre des souches bactériennes Gram-positive mais aussi Gram-négative a été prouvée pour toutes les surfaces préparées. Des propriétés intéressantes relatives au domaine des emballage actifs ont aussi été démontrées telles que la conservation d’une haute transparence et l’amélioration des propriétés barrières. Dans la seconde stratégie, des capteurs de gaz ont été préparés en utilisant un mélange actif composé de Cuivre benzène-1,3,5-tricarboxylate Metal Organic Framework et de carbone-graphène, déposé sur des électrodes flexibles produites par sérigraphie. Les capteurs sont faciles à produire et ont été optimisés pour présenter de bonnes performances à la fois pour détecter et quantifier l’ammoniac gazeux mais aussi servir de capteurs d’humidité, ce qui prouve leur versatilité et leur important potentiel industriel. Ce projet a donc conduit à différentes solutions innovantes qui peuvent relever les défis de l’industrie des emballages.

In line with the latest innovations in the packaging field, this joint project aims at implementing new and innovative micro- and nanoparticles for the development of active and intelligent packaging solutions dedicated to food and medical packaging applications. More specifically, the project combines two major developments which both falls within the scope of active and intelligent packaging. In this work, a specific focus was given to the development of an antibacterial packaging solution and to the development of smart gas sensors. The antibacterial strategy developed was based on the combination of two active materials - silver nanowires and cellulose nanofibrils - to prepare antibacterial surfaces. The formulation as an ink and the deposition processing has been deeply studied for different surface deposition processes that include coatings or screen-printing. Results showed surfaces that display strong antibacterial activity both against Gram-positive and Gram-negative bacteria, but also interesting properties for active packaging applications such as a highly retained transparency or enhanced barrier properties. Regarding the second strategy, gas sensors have been prepared using a combination of Copper benzene-1,3,5-tricarboxylate Metal Organic Framework and carbon-graphene materials, deposited on flexible screen-printed electrodes. The easy-to-produce and optimized sensors exhibit good performances toward ammonia and toward humidity sensing, proving the versatility and the great potential of such solution to be adapted for different target applications. The results of this project lead to innovative solutions that can meet the challenges raised by the packaging industry.; En lien avec les dernières innovations dans le domaine des emballages, ce projet collaboratif a pour but d’implémenter de nouveaux micro- et nanomatériaux innovants pour le développement d’emballages actifs et intelligents dans le domaine alimentaire et médical. Il se focalise en particulier sur deux stratégies : le développement d’emballages antibactériens d’un côté et de capteurs de gaz de l’autre. La première stratégie est donc dédiée à l’utilisation combinée de nanofils d’argent et de nanofibrilles de cellulose pour la production de surfaces antibactériennes. La formulation d’encres ainsi que les paramètres de dépôt ont été optimisés pour différent procédés tels que l’enduction ou l’impression sérigraphique. Une forte activité antibactérienne contre des souches bactériennes Gram-positive mais aussi Gram-négative a été prouvée pour toutes les surfaces préparées. Des propriétés intéressantes relatives au domaine des emballage actifs ont aussi été démontrées telles que la conservation d’une haute transparence et l’amélioration des propriétés barrières. Dans la seconde stratégie, des capteurs de gaz ont été préparés en utilisant un mélange actif composé de Cuivre benzène-1,3,5-tricarboxylate Metal Organic Framework et de carbone-graphène, déposé sur des électrodes flexibles produites par sérigraphie. Les capteurs sont faciles à produire et ont été optimisés pour présenter de bonnes performances à la fois pour détecter et quantifier l’ammoniac gazeux mais aussi servir de capteurs d’humidité, ce qui prouve leur versatilité et leur important potentiel industriel. Ce projet a donc conduit à différentes solutions innovantes qui peuvent relever les défis de l’industrie des emballages.

International audience; This experimental study investigates blade root load fluctuations for a single turbine immersed in a regular current flow with different ambient turbulence conditions. Two scaled models of industrial prototypes were tested: a 1:28 scale model of the three-bladed horizontal axis turbine of Magallanes Renovables and a 1:20 scale model of the five-bladed horizontal axis turbine of Sabella. The rotor loads were directly measured on the rotation axis with a thrust and torque sensor. The blade roots were equipped with a load-cell measuring two forces and three moments. The variations of the rotor loads (thrust and torque) and the blade root loads (edgewise bending moments and streamwise forces) are compared and the impact of the blade angular position is investigated. A comparison of both scaled models results with those of the IFREMER generic turbine is also presented. The results are anonymised in order to ensure confidentiality.

International audience; High Entropy Alloys (HEA) can be classified in three domains according to their e/a and r values, with e/a, the number of itinerant valence electrons and r the average radius for a 12 nearest atoms neighborhood. The phase composition, thermal stability and possible phase transformations of a series of HEA alloys, CoCrzFeNi-XY (with X and Y = Al, Cu, Pd, Ru, Ti and z=0 or 1), selected according to their e/a ratio were investigated in cast conditions (T0), after 3 hours homogenization at 1100°C (T1) and after 3 hours annealing at 700°C (T3). It is observed that for the alloys from domain I which contains fcc structures, the microstructure transforms from multi-to almost single-phase under homogenization (T1). In domain III alloys contains cubic (bcc and/or B2) structures very small multi-structural changes are observed. Alloys in domain II have mixed structure, i.e. several different structures in the diffraction pattern, which changes during heat treatments.

International audience; High dose selenium acts as a cytotoxic agent, with potential applications in cancer treatment. However, clinical trials have failed to show any chemotherapeutic value of selenium at safe and tolerated doses (

International audience; The seismoelectric method holds great promise in the delineation and hydraulic characterization of thin subglacial layers of deformable sediments, subglacial water bodies, and deeper groundwater and heat‐bearing rocks. Of particular value are subglacial interfacial conversions and, potentially, evanescent electromagnetic waves converted at shallow englacial interfaces. We present three case studies that examine the seismoelectric direct field in wet snow, coseismic responses of wet glacier ice and till substrate, and interfacial conversions in a dry glacier and bedrock substrate, having amplitudes on respective orders of ~10^1–10^2, 10^0–10^1, and 10^{−3} mV. The electrokinetically controlled direct field and coseismic responses are large and consistent with strong electrical streaming potential amplitudes in wet snow and wet glacier ice, probably because electrical conductivities of meltwaters are commonly very low (~10^{−4}–10^{−6} S/m). Interfacial conversions in the wet glacier case may likewise have been amplified, but could not be unequivocally identified here due to a lack of diagnostic move‐out information. In the dry glacier case, direct field and coseismic effects were negligible and interfacial responses readily detected despite their small amplitudes. Vast swathes of continental ice sheets and glaciers reside in electromagnetically quiet environments, and have dry upper ice, firn, and snow layers as well as substrates saturated with low‐conductivity meltwaters. They should therefore provide favorable environments for the measurement and physical evaluation of interfacial conversions from either wet or dry basal environments, with crucial implications for the dynamics, hydrology, microbiology, and thermal budget of and methane deposits beneath the world's ice sheets and glaciers.

International audience; Type II solar radio bursts have proven to be a useful tool for gaining insights into the behaviour of complex solar events and for forecasting and mitigating their damages on Earth. In this work, we detect and segment the occurrence of type II bursts in solar radio spectrograms, thereby facilitating the extraction of parameters needed to gain insight into solar events. We utilise prior knowledge of how type II bursts drift through frequencies over time to assist with these tasks of detection and segmentation. A new adaptive Region of Interest (ROI) is proposed, to constrain the search to regions that follow the burst curvature at a given frequency. It comes with an implicit data normalisation that reduces the variance of burst appearance in the data, hence simplifying the learning process from small datasets. We demonstrate the effectiveness of our methodology using a simple and popular HOG and logistic regression detector and basic segmentation based on voting and background subtraction. On a custom dataset representative of different levels of solar activity, at a wavelength range where no other detection algorithm currently operates, our adaptive ROI significantly improves over traditional sliding windows. In future work, it may be applied to other, state-of-the-art, machine learning algorithms.

International audience; Silicone polymers have enormous applications, especially in the areas of biomedical engineering. Ecoflex, a commercially available room temperature cured silicone polymer, has attracted considerable attention due to its wide range of applications as medical-grade silicones and as matrix materials in producing nano-filled stretchable sensors and dielectric elastomers for soft robotics. In this contribution, we have conducted a wide range of experiments under thermo-mechanical loadings. These experiments consist of loading-unloading cyclic tests, single-step relaxation tests, Mullins effects tests at different strain rates and stretches, stress recovery tests at different rest time etc. In order to assess the temperature influences on Ecoflex, a number of viscoelastic tests are performed in a thermal chamber with temperature ranging from-40 • C to 140 • C. Extensive experimental findings illustrate that Ecoflex experiences a significant stress softening in the first cycles and such a softening recovers gradually with respect to time. It also shows a significant amount of cyclic dissipation at various stretch levels as well as a considerable stress relaxation only for virgin samples. Cyclic dissipations and stress relaxation almost disappear for the case of pre-stretched samples. Furthermore, the material is more or less sensitive under a wide range of temperature differences.

The liver is the largest internal organ and plays an important part in maintaining the homeostatic balance in the body. It is also one of the primary sites of nanoparticle accumulation. HepG2 spheroids were used as an in vitro model to assess iron oxide (magnetite, Fe3O4 and maghemite, γ-Fe2O3) nanoparticle (NP) toxicity. The development of HepG2 spheroids by the hanging drop method was illustrated through cell viability and tissue morphology assessment of spheroids generated from 1000, 5000, and 10,000 cells per drop. The spheroids generated from 5000 cells per drop had the most optimal configuration. Liver function was assessed by albumin, urea and aspartate transaminase which were expressed in physiologically relevant concentrations by the HepG2 spheroid.Synchrotron X-ray fluorescence (SXRF) was used to assess NP distribution and metal homeostasis. The SXRF studies showed a dose-dependent accumulation of NPs inHepG2 spheroid transverse tissue sections. This accumulation also affected ironhomeostasis by significantly increasing intracellular copper levels. The elemental distribution of calcium and selenium also increased upon challenge with NPs, whichmay be involved in the removal of reactive oxygen species (ROS). Glucose metabolism shifted towards anaerobic respiration in presence NPs, exhibiting the Warburg effect. Transmission electron microscopy also shows intracellular localisation of the iron oxide NPs. Cytokinesis block micronucleus (CBMN) and single-cell gel electrophoresis (comet) assays were used to assess genotoxicity. Both NPs induced a significant increase in micronuclei frequency. Pan-centromeric staining further indicated that the primary mode of action of DNA damage caused by iron oxide NPs was clastogenic. Comet scores showed no significant increases in tail intensities percentages. In conclusion, the HepG2 spheroid model is representative of an in vivo liver due to its ability to mimic glucose metabolism, liver functionality and metal homeostasis responses. Iron oxide NPs cause the HepG2 spheroids to respire anaerobically and disrupt iron homeostasis which can potentially lead to the generation of ROS resulting in the DNA damage., Le foie est le plus grand organe interne et joue un rôle important dans le maintien de l'équilibre homéostatique dans le corps. C'est également l'un des principaux sites d'accumulation de nanoparticules. Les sphéroïdes HepG2 ont été utilisés comme modèle in vitro pour évaluer la toxicité des nanoparticules (NP) d'oxyde de fer (magnétite, Fe3O4 et maghémite, γ-Fe2O3). Le développement des sphéroïdes HepG2 par la méthode des gouttes suspendues a été quantifié par l’évaluation de la viabilité cellulaire et de la morphologie des tissus des sphéroïdes générés à partir de 1000, 5000 et 10 000 cellules par goutte. Les sphéroïdes générés à partir de 5000 cellules par goutte avaient la configuration la plus optimale. La fonction hépatique a été évaluée par l'albumine, l'urée et l'aspartate transaminase, qui ont été exprimées à des concentrations physiologiquement pertinentes par le sphéroïde HepG2.La fluorescence des rayons X synchrotron (SXRF) a été utilisée pour évaluer la distribution des NP et l'homéostasie des métaux. Les études SXRF montrent une accumulation dépendante de la dose de NP dans les coupes transversales de tissu sphéroïde HepG2. Cette accumulation a également affecté l'homéostasie du fer en augmentant de manière significative les niveaux de cuivre intracellulaire. Lesconcentrations du calcium et du sélénium ont également augmenté en présence desNP, ces deux éléments pouvant être impliquées dans l'élimination des espèces réactives de l'oxygène (ROS). Le métabolisme du glucose s'est déplacé vers la respiration anaérobie en présence de NP, montrant l'effet Warburg. La microscopie électronique à transmission montre également la localisation intracellulaire des NP d'oxyde de fer. L'analyse des micronoyaux par blocage de la cytokinèse (CBMN) et l'électrophorèse en gel unicellulaire (comet) ont été utilisées pour évaluer la génotoxicité. Les deux NP ont induit une augmentation significative de la fréquence des micronoyaux. La coloration pan-centromérique a en outre indiqué que le principal mode d'action des dommages à l'ADN causés par les NP d'oxyde de fer était le clastogène. Les résultats comet n'ont montré aucune augmentation significative des pourcentages d'intensité de la queue.En conclusion, le modèle sphéroïde HepG2 est représentatif d'un foie in vivo en raison de sa capacité à imiter le métabolisme du glucose, la fonctionnalité du foie et les réponses à l'homéostasie des métaux. Les NP d'oxyde de fer amènent un métabolismedes sphéroïdes HepG2 anaérobie et perturbent l'homéostasie du fer, ce qui peut potentiellement générer la génération de ROS entraînant des lésions de l'ADN.

International audience; According to a recent Hume-Rothery approach, the electron concentration, e/a, and the average radius can be used to identify the domain of stability of HEAs and to estimate the phases that may occur in the alloy. The present study investigates the influence of the electronic polymorphism of nickel on the efficiency of the classification and on the design of HEAs for magnetic applications. Many different compositions were used, based on 4 to 7 elements out of a total 13 different elements (Co, Cr, Fe, Ni, Al, Cu, Pd, Ti, Mn, V, Nb, Sn, Ru). Phases have been determined by X-ray and neutron diffraction as well as in some cases high energy X-ray diffraction. The e/a for the constituent elements is calculated according to Massalski. The two polymorphic electronic structure of nickel, namely (e/a) Ni ¼ 1 or (e/a) Ni ¼ 2 are considered. The average e/a for the alloy is calculated assuming a solid solution case. The electronic structure [Ar] 3d 9 4s 1 seems to be more appropriate for the classification of HEAs. Based on a Self-organising Map predictions are made for the average magnetic moment at saturation for this electronic structure of Ni. Non-saturated values and data from the literature are compared with the predictions. The consequences of such results when modelling the structure and properties of Ni containing HEAs are presented, in particular the consideration of the shape and transformation of the Brillouin zone.

Workshop, Due to the COVID-19 pandemic, the event has been cancelled.; International audience; Art and design are essential aspects of our culture and how we interact with the world. Artists and designers use a wide selection of tools, whose impact is rapidly growing with the progression of digital technologies. This change has opened up new opportunities for the CHI community to build creative supportive tools. The digital switch has come with many benefits such as lowering barriers, mobile work environments and mass production for distribution of work. Along with these benefits we also see challenges for art and design work and its future perception in society. As technology takes a more significant role in supporting art and design what will this mean for the individual artist or designer? The focus of this workshop is to bring together researchers and practitioners to explore what the future of digital art and design will hold. The exploration will centre around synthesizing key challenges and questions, along with ideas for future interaction technologies that consider mobile and tangible aspects of digital art.

It is evidently not trivial to analytically solve practical engineering problems due to their inherent (geometrical and/or material) nonlinearities. Moreover, experimental testing can be extremely costly, time-consuming and even dangerous, in some cases. In the past few decades, therefore, numerical techniques have been progressively developed and utilised in order to investigate complex engineering applications through computer simulations, in a cost-effective manner.An important feature of a numerical methodology is how to approximate a physical domain into a computational domain and that, typically, can be carried out via mesh-based and particle-based approximations, either of which manifest with a different range of capabilities. Due to the geometrical complexity of many industrial applications (e.g. biomechanics, shape casting, metal forming, additive manufactur-ing, crash simulations), a growing attraction has been received by tetrahedral mesh generation, thanks to Delaunay and advancing front techniques [1, 2]. Alternatively, particle-based methods can be used as they offer the possibility of tackling specific applications in which mesh-based techniques may not be efficient (e.g. hyper velocity impact, astrophysics, failure simulations, blast).In the context of fast thermo-elastodynamics, modern commercial packages are typically developed on the basis of second order displacement-based finite element formulations and, unfortunately, that introduces a series of numerical shortcomings such as reduced order of convergence for strains and stresses in comparison with displacements and the possible onset of numerical instabilities (e.g. detrimental locking, hour-glass modes, spurious pressure oscillations).To rectify these drawbacks, a mixed-based set of first order hyperbolic conservation laws for isothermal elastodynamics was presented in [3–6], in terms of the linear momentum p per unit undeformed volume and the minors of the deformation, namely, the deformation gradient F , its co-factor H and its Jacobian J. Taking inspiration of these works [4, 7] and in order to account for irreversible processes, the balance of total energy (also known as the first law of thermodynamics) is incorporated to the set of physical laws used to describe the deformation process. This, in general, can be expressed in terms of the entropy density η or total energy density E by which the Total Lagrangian entropy-based and total energy-based formulations {p, F , H, J, η or E} are established, respectively. Interestingly, taking advantage of the conservation formulation framework, it is possible to bridge the gap between solid dynamics and Computational Fluid Dynamics (CFD) by exploiting available CFD techniques in the context of solid dynamics.From a computational standpoint, two distinct and extremely competitive spatial discretisations are employed, namely, mesh-based Vertex-Centred Finite Volume Method (VCFVM) and meshless Smooth Particle Hydrodynamics (SPH). A linear reconstruction procedure together with a slope limiter is employed in order to ensure second order accuracy in space whilst avoiding numerical oscillations in the vicinity of sharp gradients, respectively. Crucially, the discontinuous solution for the conservation variables across (dual) control volume interfaces or between any pair of particles is approximated via an acoustic Riemann solver. In addition, a tailor-made artificial compressibility algorithm and an angular momentum preservation scheme are also incorporated in order to assess same limiting scenarios.The semi-discrete system of equations is then temporally discretised using a one-step two-stage Total Variation Diminishing (TVD) Runge-Kutta time integrator, providing second order accuracy in time. The geometry is also monolithically updated to be only used for post-processing purposes.Finally, a wide spectrum of challenging examples is presented in order to assess both the performance and applicability of the proposed schemes. The new formulation is proven to be very efficient in nearly incompressible thermo-elasticity in comparison with classical finite element displacement-based approaches. The proposed computational framework provides a good balance between accuracy and speed of computation.

International audience; While cryptosporidiosis is recognized as being among the most common causes of human parasitic diarrhea in the world, there is currently limited knowledge on Cryptosporidium infection mechanisms, incomplete codification of diagnostic methods, and a need for additional therapeutic options. In response, the Seventh International Giardia and Cryptosporidium Conference (IGCC 2019) was hosted from 23 to 26 June 2019, at the Rouen Normandy University, France. This trusted event brought together an international delegation of researchers to synthesize recent advances and identify key research questions and knowledge gaps. The program of the interdisciplinary conference included all aspects of host-parasite relationships from basic research to applications to human and veterinary medicine, and environmental issues associated with waterborne parasites and their epidemiological consequences. In relation to Cryptosporidium and cryptosporidiosis, the primary research areas for which novel findings and the most impressive communications were presented and discussed included: Cryptosporidium in environmental waters, seafood, and fresh produce; Animal epidemiology; Human cryptosporidiosis and epidemiology; Genomes and genomic evolution encompassing: Comparative genomics of Cryptosporidium spp., Genomic insights into biology, Acquiring and utilizing genome sequences, Genetic manipulation; Host-parasite interaction (immunology, microbiome); and Diagnosis and treatment. High quality presentations discussed at the conference reflected decisive progress and identified new opportunities that will engage investigators and funding agencies to spur future research in a "one health" approach to improve basic knowledge and the clinical and public health management of zoonotic cryptosporidiosis.; Bien que la cryptosporidiose soit reconnue comme l’une des premières causes de diarrhée parasitaire humaine dans le monde, la connaissance des mécanismes de l’infection par Cryptosporidium est limitée, la codification des méthodes diagnostiques est incomplète et des options thérapeutiques supplémentaires sont requises. En réponse à cette situation, la Septième Conférence Internationale sur Giardia and Cryptosporidium (IGCC 2019) s’est tenue du 23 au 26 juin 2019, à l’Université de Rouen-Normandie, France. Cet événement renommé a rassemblé une délégation internationale de chercheurs pour faire la synthèse des avancées récentes et identifier les principaux thèmes de recherche et les lacunes dans les connaissances. Le programme de cette conférence interdisciplinaire comprenait tous les aspects des relations hôte-parasite, de la recherche fondamentale aux applications à la médecine humaine et vétérinaire, ainsi que les questions environnementales liées aux parasites d’origine hydrique et leurs conséquences épidémiologiques. En ce qui concerne Cryptosporidium et la cryptosporidiose, les principaux domaines de recherche pour lesquels de nouvelles découvertes et les communications les plus impressionnantes ont été présentées et discutées comprenaient : Cryptosporidium dans les eaux environnementales, les fruits de mer et les produits frais ; Épidémiologie animale ; Cryptosporidiose et épidémiologie humaine ; Génomes et évolution génomique englobant : Génomique comparative des Cryptosporidium spp., Perspectives génomiques en biologie, Acquisition et utilisation des séquences du génome, Manipulation génétique ; Interaction hôte-parasite (immunologie, microbiome) ; Diagnostic et traitement. Les présentations de grande qualité discutées à la conférence ont fait état de progrès décisifs et ont permis de cerner de nouvelles possibilités qui inciteront les chercheurs et les organismes de financement à stimuler la recherche future dans une approche « une seule santé » afin d’améliorer les connaissances de base et la gestion clinique et de santé publique de la cryptosporidiose zoonotique.

International audience; Turbulence is a crucial flow phenomenon for tidal energy converters (TECs), as it influences both the peak loads they experience and their fatigue life. To best mitigate its effects we must understand both turbulence itself and how it induces loads on TECs. To that end, this paper presents the results of blade element momentum theory (BEMT) simulations of flume-scale TEC models subjected to synthetic turbulent flows. Synthetic turbulence methods produce three-dimensional flowfields from limited data, without solving the equations governing fluid motion. These flowfields are non-physical, but match key statistical properties of real turbulence and are much quicker and computationally cheaper to produce. This study employs two synthetic turbulence generation methods: the synthetic eddy method and the spectral Sandia method. The response of the TECs to the synthetic turbulence is predicted using a robust BEMT model, modified from the classical formulation of BEMT. We show that, for the cases investigated, TEC load variability is lower in stall operation than at higher tip speed ratios. The variability of turbine loads has a straightforward relationship to the turbulence intensity of the inflow. Spectral properties of the velocity field are not fully reflected in the spectra of TEC loads.

International audience; Parent-athlete relationships are central to athletes' optimal well-being and experiences in sport. Nonetheless, despite being considered within numerous theories and models, parentathlete relationships are often only studied implicitly. Thus, the purpose of this review is to critically examine theory and research pertaining to parent-athlete relationships in youth sport and provide suggestions regarding how to move this area of research forwards. Specifically, a review of the family-systems theory, the bioecological model, competence motivation theory, expectancy-value theory, self-determination theory, achievement goal theory, parenting styles, and attachment theory is provided. Subsequently, arguments for the potential benefit of utilising Reis at al's (2004) construct of responsiveness (i.e., how people in a relationship attend and support each other's needs and goals) to improve understanding of parent-athlete relationships are presented. Finally, a model for studying parent-athlete relationships based on Feeney and Collins' (2015) thriving through relationships is suggested. We believe that this model may be useful for integrating key elements of existing theories as they pertain to parent-athlete relationships while also provide fruitful avenues for more in-depth and explicit examinations of parent-athlete relationships within youth sport.

The liver is the largest internal organ and plays an important part in maintaining the homeostatic balance in the body. It is also one of the primary sites of nanoparticle accumulation. HepG2 spheroids were used as an in vitro model to assess iron oxide (magnetite, Fe3O4 and maghemite, γ-Fe2O3) nanoparticle (NP) toxicity. The development of HepG2 spheroids by the hanging drop method was illustrated through cell viability and tissue morphology assessment of spheroids generated from 1000, 5000, and 10,000 cells per drop. The spheroids generated from 5000 cells per drop had the most optimal configuration. Liver function was assessed by albumin, urea and aspartate transaminase which were expressed in physiologically relevant concentrations by the HepG2 spheroid.Synchrotron X-ray fluorescence (SXRF) was used to assess NP distribution and metal homeostasis. The SXRF studies showed a dose-dependent accumulation of NPs inHepG2 spheroid transverse tissue sections. This accumulation also affected ironhomeostasis by significantly increasing intracellular copper levels. The elemental distribution of calcium and selenium also increased upon challenge with NPs, whichmay be involved in the removal of reactive oxygen species (ROS). Glucose metabolism shifted towards anaerobic respiration in presence NPs, exhibiting the Warburg effect. Transmission electron microscopy also shows intracellular localisation of the iron oxide NPs. Cytokinesis block micronucleus (CBMN) and single-cell gel electrophoresis (comet) assays were used to assess genotoxicity. Both NPs induced a significant increase in micronuclei frequency. Pan-centromeric staining further indicated that the primary mode of action of DNA damage caused by iron oxide NPs was clastogenic. Comet scores showed no significant increases in tail intensities percentages. In conclusion, the HepG2 spheroid model is representative of an in vivo liver due to its ability to mimic glucose metabolism, liver functionality and metal homeostasis responses. Iron oxide NPs cause the HepG2 spheroids to respire anaerobically and disrupt iron homeostasis which can potentially lead to the generation of ROS resulting in the DNA damage., Le foie est le plus grand organe interne et joue un rôle important dans le maintien de l'équilibre homéostatique dans le corps. C'est également l'un des principaux sites d'accumulation de nanoparticules. Les sphéroïdes HepG2 ont été utilisés comme modèle in vitro pour évaluer la toxicité des nanoparticules (NP) d'oxyde de fer (magnétite, Fe3O4 et maghémite, γ-Fe2O3). Le développement des sphéroïdes HepG2 par la méthode des gouttes suspendues a été quantifié par l’évaluation de la viabilité cellulaire et de la morphologie des tissus des sphéroïdes générés à partir de 1000, 5000 et 10 000 cellules par goutte. Les sphéroïdes générés à partir de 5000 cellules par goutte avaient la configuration la plus optimale. La fonction hépatique a été évaluée par l'albumine, l'urée et l'aspartate transaminase, qui ont été exprimées à des concentrations physiologiquement pertinentes par le sphéroïde HepG2.La fluorescence des rayons X synchrotron (SXRF) a été utilisée pour évaluer la distribution des NP et l'homéostasie des métaux. Les études SXRF montrent une accumulation dépendante de la dose de NP dans les coupes transversales de tissu sphéroïde HepG2. Cette accumulation a également affecté l'homéostasie du fer en augmentant de manière significative les niveaux de cuivre intracellulaire. Lesconcentrations du calcium et du sélénium ont également augmenté en présence desNP, ces deux éléments pouvant être impliquées dans l'élimination des espèces réactives de l'oxygène (ROS). Le métabolisme du glucose s'est déplacé vers la respiration anaérobie en présence de NP, montrant l'effet Warburg. La microscopie électronique à transmission montre également la localisation intracellulaire des NP d'oxyde de fer. L'analyse des micronoyaux par blocage de la cytokinèse (CBMN) et l'électrophorèse en gel unicellulaire (comet) ont été utilisées pour évaluer la génotoxicité. Les deux NP ont induit une augmentation significative de la fréquence des micronoyaux. La coloration pan-centromérique a en outre indiqué que le principal mode d'action des dommages à l'ADN causés par les NP d'oxyde de fer était le clastogène. Les résultats comet n'ont montré aucune augmentation significative des pourcentages d'intensité de la queue.En conclusion, le modèle sphéroïde HepG2 est représentatif d'un foie in vivo en raison de sa capacité à imiter le métabolisme du glucose, la fonctionnalité du foie et les réponses à l'homéostasie des métaux. Les NP d'oxyde de fer amènent un métabolismedes sphéroïdes HepG2 anaérobie et perturbent l'homéostasie du fer, ce qui peut potentiellement générer la génération de ROS entraînant des lésions de l'ADN.

Ovarian cancer is the seventh most common cancer in women with five-year survival rates of less than 45%, and only 20% of cases are detected at early stages of the disease. Major challenges still exist to treat this lethal disease.The development of new drugs that target better cancer cells and reduce side effects is highly needed. Selenium at high doses has been shown to act as a cytotoxic agent, with potential applications in cancer treatment. However, clinical trials have failed to show any chemotherapeutic value of selenium at safe and tolerated doses (, Le cancer des ovaires est le septième cancer le plus commun chez les femmes dont le taux de survie à 5 ans est en deçà de 45% et dont le taux de détection des premiers stades de développement est inférieur à 20%. Avant d’arriver à un traitement, de nombreux défis restent à relever.Le développement de nouveaux traitements ciblant spécifiquement les cellules cancéreuses en réduisant les effets secondaires liés au traitement est nécessaire. Pour cela, le Sélénium a été étudié et a démontré à forte doses d’être efficace contre les cellules cancéreuses in vitro. De plus, les essais cliniques ont montré que l’utilisation de doses tolérables de sélénium (

International audience; Cost, driven mostly by planned and unplanned maintenance, is the most significant barrier limiting widespread adoption of TECs. Accurate numerical models can be used to predict the structural loads on TECs and help improve their reliability. BEMT offers an efficient method for predicting the performance of TECs. A robust but unoptimized BEMT code, implemented in MATLAB, has been developed at Swansea University. Previous versions of the BEMT code only allowed for inputs of constant blade profile and Reynolds Number which contributed to the inaccuracies of the BEMT model in predicting experimental results. We present a faster and more accurate C++ implementation of the BEMT code. The error between the coefficient of power from the BEMT code and results of laboratory testing at optimum TSR was reduced by 13%. This should in turn improve the design of TEC, reducing their cost and increase their adoption as generators of low carbon energy.

Using numerical simulations of lattice QCD with physical quark masses, we reveal the influence of magnetic-field background on chiral and deconfinement crossovers in finite-temperature QCD at low baryonic density. In the absence of thermodynamic singularity, we identify these transitions with inflection points of the approximate order parameters: normalized light-quark condensate and renormalized Polyakov loop, respectively. We show that the quadratic curvature of the chiral transition temperature in the ``temperature--chemical potential'' plane depends rather weakly on the strength of the background magnetic field. At weak magnetic fields, the thermal width of the chiral crossover gets narrower as the density of the baryon matter increases, possibly indicating a proximity to a real thermodynamic phase transition. Remarkably, the curvature of the chiral thermal width flips its sign at $eB_{\mathrm{fl}} \simeq 0.6\,\mathrm{GeV}^2$, so that above the flipping point $B > B_{\mathrm{fl}}$, the chiral width gets wider as the baryon density increases. Approximately at the same strength of magnetic field, the chiral and deconfining crossovers merge together at $T \approx 140\,\mathrm{MeV}$. The phase diagram in the parameter space ``temperature-chemical potential-magnetic field'' is outlined, and single-quark entropy and single-quark magnetization are explored. The curvature of the chiral thermal width allows us to estimate an approximate position of the chiral critical endpoint at zero magnetic field: $(T_c^{\text{CEP}}, ��_B^{\text{CEP}})= (100(25)\, \text{MeV},\ 800(140)\,\text{MeV})$., 22 pages, 17 figures; a video file revealing the evolution of the phase diagram is attached

Wide bandgap semiconductor materials are able to withstand harsh environments and operate over a wide range of temperatures. These make them ideal for many applications such as sensors, high-power and radio-frequencies to name a few.However, more novel materials are required to achieve significant power efficiency of various applications or to develop new applications to complement current wide bandgap semiconductors such as GaN and SiC.In this dissertation, three different methods are used to study one of these novelmaterials, aluminium silicon carbide (Al4SiC4): (1) ensemble Monte Carlo simulationsin order to study the electron transport properties of the novel ternary carbide, (2)experimental studies to determine its material properties, and (3) device simulationsof a heterostructure device made possible by this ternary carbide. All these methodsinterlink with each other. Data from each of them can feed into the other to acquire newresults or refine obtained results thus leading way to attractive electrical properties such as a bandgap of 2.78 eV or a peak drift velocity of 1.35×10 cm s .Ensemble Monte Carlo toolbox, developed in-house for simulations of Si, Ge, GaAs,AlxGa1−xAs, AlAs, and InSb; is adopted for simulations of the ternary carbide by adding anew valley transformation to account for the hexagonal structure of Al4SiC4. We predicta peak electron drift velocity of 1.35×107 cms−1 at electric field of 1400 kVcm−1 and a maximum electron mobility of 82.9 cm V s . We have seen a diffusion constant of 2.14 cm2s−1 at a low electric field and of 0.25 cm2s−1 at a high electric field. Finally, weshow that Al4SiC4 has a critical field of 1831 kVcmsemiconductor crystals are used that had previously been grown at IMGP, one by solution grown and the other by crucible melt. Three different experiments are performed on them; (1) UV, IR and Vis Spectroscopy, (2) X-ray Photo Spectroscopy, and (3) Two- and four-probe measurements where metal contact are grown on the crystals. Here we have found a bandgap of 2.78 ± 0.02 eV UV, IR and Vis Spectroscopy and a thick oxide layer on the samples using XPS. Unfortunately the Two- and four-probe measurements failed to give any results other than noise, most likely due to the thick oxide layer that was found on the samples.In the device simulations, a commercial software Atlas by Silvaco is utilized to predict performance of heterostructure devices, with gates lengths of 5 μm, 2 μm and 1 μm, made possible by the ternary carbide in a combination with SiC. The 5 μm gate length SiC/Al4SiC4 heterostructure transistor delivers a maximum drain current of 1.68×10−4 A/μm, which increases to 2.44×10−4 A/μm and 3.50×10−4 A/μm for gate lengths of 2 μm and 1 μm, respectively. The device breakdown voltage is 59.0 V which reduces to 31.0 V and to 18.0 V for the scaled 2 μm and the 1 μm gate length transistors. The scaled down 1 μm gate length device switches faster because of the higher transconductance of6.51×10−5 S/μmcomparedtoonly1.69×10−6 S/μmforthelargestdevice.Finally,a sub-threshold slope of the scaled devices is 197.3 mV/dec, 97.6 mV/dec, and 96.1 mV/dec for gate lengths of 5 μm, 2 μm, and 1 μm, respectively., Les matériaux semi-conducteurs à large bande interdite sont capables de résister aux environnements difficiles et de fonctionner dans une large plage de températures. Celles-ci sont idéales pour de nombreuses applications telles que les capteurs, la haute puissance et les radiofréquences.Cependant, des matériaux plus nouveaux sont nécessaires pour atteindre une efficacité énergétique significative dans diverses applications ou pour développer de nouvelles applications destinées à compléter les semi-conducteurs à bande interdite tels que le GaN et le SiC.Dans cette thèse, trois méthodes différentes sont utilisées pour étudier l’un de ces nouveauxmatériaux, carbure d'aluminium et de silicium (Al4SiC4): (1) simulations d'ensemble de Monte Carloafin d'étudier les propriétés de transport d'électrons du nouveau carbure ternaire, (2)études expérimentales pour déterminer ses propriétés matérielles et (3) simulations de dispositifsd'un dispositif à hétérostructure rendu possible par ce carbure ternaire. Toutes ces méthodesinterconnecter les uns avec les autres. Les données de chacun d’eux peuvent alimenter l’autre pour acquérir de nouvelles connaissances.résultats ou affiner les résultats obtenus conduisant ainsi à des propriétés électriques attrayantes telles qu’une bande interdite de 2,78 eV ou une vitesse de dérive maximale de 1,35 × 10 cm s.Ensemble Monte Carlo, développé en interne pour les simulations de Si, Ge, GaAs,AlxGa1-xAs, AlAs et InSb; est adopté pour les simulations du carbure ternaire en ajoutant untransformation de la nouvelle vallée pour tenir compte de la structure hexagonale de Al4SiC4. Nous prédisonsune vitesse maximale de dérive des électrons de 1,35 × 107 cm-1 à un champ électrique de 1400 kVcm-1 et une mobilité maximale des électrons de 82,9 cm V s. Nous avons vu une constante de diffusion de 2,14 cm2s-1 à un champ électrique faible et de 0,25 cm2s-1 à un champ électrique élevé. Enfin nousmontrer que Al4SiC4 a un champ critique de 1831 kVcmOn utilise des cristaux semi-conducteurs qui avaient été cultivés auparavant à l’IMGP, l’un par la croissance en solution et l’autre par la fusion en creuset. Trois expériences différentes sont effectuées sur eux; (1) spectroscopie UV, IR et visuelle, (2) spectroscopie photographique à rayons X, et (3) mesures à deux et à quatre sondes dans lesquelles un contact métallique est formé sur les cristaux. Nous avons trouvé ici une bande interdite de spectroscopie UV, IR et Vis de 2,78 ± 0,02 eV et une couche d’oxyde épaisse sur les échantillons en utilisant du XPS. Malheureusement, les mesures à deux et à quatre sondes n'ont donné aucun résultat autre que le bruit, probablement en raison de l'épaisse couche d'oxyde trouvée sur les échantillons.Dans les simulations de dispositifs, le logiciel commercial Atlas de Silvaco est utilisé pour prédire les performances des dispositifs à hétérostructure, avec des longueurs de grille de 5, 2 et 1 µm, rendues possibles par le carbure ternaire en combinaison avec du SiC. Le transistor à hétérostructure SiC / Al4SiC4 d'une longueur de grille de 5 µm délivre un courant de drain maximal de 1,68 × 10−4 A / µm, qui passe à 2,44 × 10−4 A / µm et à 3,50 × 10−4 A / µm pour des longueurs de grille de 2 µm et 1 µm, respectivement. La tension de claquage de l'appareil est de 59,0 V, ce qui réduit à 31,0 V et à 18,0 V les transistors mis à l'échelle des longueurs de grille de 2 µm et de 1 µm. Le dispositif à longueur de grille réduite de 1 μm bascule plus rapidement en raison de la transconductance supérieure de6,51 × 10−5 S / μm par rapport à une fois par an1,69 × 10−6 S / μm pour le plus grand périphérique.Enfin, une pente inférieure au seuil des dispositifs mis à l'échelle est égale à 197,3 mV / dec, 97,6 mV / dec et 96,1 mV / dec pour des longueurs de grille de 5 µm, 2 µm et 1 µm, respectivement.

During the process of wave slamming on a structure with sharp corners, the wave receding after wave impingement can induce strong negative pressure (relative to the atmospheric pressure) at the bottom of the structure, which is called the suction effect. From the practical point of view, the suction force induced by the negative pressure, coinciding with the gravity force, pulls the structure down and hence increases the risk of structural damage. In this work, the smoothed particle hydrodynamics (SPH) method, more specifically the δ+SPH model, is adopted to simulate the freak wave slamming on a fixed platform with the consideration of the suction effect, i.e., negative pressure, which is a challenging issue because it can cause the so-called tensile instability in SPH simulations. The key to overcome the numerical issue is to use a numerical technique named tensile instability control (TIC). Comparative studies using SPH models with and without TIC will show the importance of this technique in capturing the negative pressure. It is also found that using a two-phase simulation that takes the air phase into account is essential for an SPH model to accurately predict the impact pressure during the initial slamming stage. The freak wave impacts with different water depths are studied. All the multiphase SPH results are validated by our experimental data. The wave kinematics/dynamics and wave impact features in the wave-structure interacting process are discussed, and the mechanism of the suction effect characterized by the negative pressure is carefully analyzed.

Part 1: E-Business; International audience; Despite the rapid growth in mobile stores (e.g., Apple Store, Google Play), scholarly research in this area is still in the early stages. In particular, there is a need for more empirical analysis of how the main features of these new systems shape the customer experience. This study aims to empirically identify and validate the key factors shaping users’ satisfaction toward mobile stores. The conceptual model was proposed based on a group of the main factors from the extended Unified Theory of Acceptance and Use of Technology (UTAUT2), mobile interactivity, and perceived security and privacy. The empirical analysis was conducted in Jordan by collecting data from a convenience sample of users of mobile stores. Structural equation modelling was applied to test the current study’s model. The results support the significant impact of performance expectancy, price value, hedonic motivation, personalization, responsiveness, and perceived security and privacy on user satisfaction. Discussion of the main limitations and future research directions are also provided.

Part 12: Digital Innovation and Business Transformation; International audience; Open innovation ecosystems rely upon inter-organisational knowledge transfer to support co-creation. Despite the significance of this process, and an abundance of open innovation research, empirical investigation and discussion of diverse knowledge transfer conditions across open innovation ecosystems remains unaddressed within existing literature. Using a mixed-method approach, this study investigates how knowledge, firm, and partner-relationship characteristics affect the successful exchange of knowledge between ecosystem partners. Interpretive Structural Modelling was employed to ascertain expert opinions regarding the interrelations between the transfer conditions. The combinatory nature of these conditions, and their integration into solutions for success, was further explored utilizing fuzzy-set Qualitative Comparative Analysis. Results indicate that conditions for knowledge transfer success are highly interrelated and co-dependent. Limitations and implications are discussed.

Part 6: Social Media and Analytics; International audience; Ever since demonetization happened in India on November 8, 2016, there has been a steady improvement in the use of digital payments. The usage trend has become exponential in the last 15 months across the digital payment methods (DPMs) in India. Government of India is promoting this landmark change of Indian financial system through Digital India initiative. Both national and international corporates, established as well as startups are investing heavily in DPMs to promote their products and services among Indian consumers. The promotion of DPMs also includes the use of social media marketing. Social media (especially Twitter) is being extensively used by companies to make the consumer aware about their services and promote themselves. The consumers do get motivated to try and use their services but they also share their grudges on Twitter. This paper aims to analyze DPMs adoption in India using Twitter as a tool. This study collected 172996 tweets over a period of four months and analyzed using a mix of conventional as well novel social media analytics techniques. Our analysis highlights the critical factors that drive and inhibit the use of DPMs in India. Further, our state wise analysis clearly differentiates about DPM adoption rate from high to low in all states of India.

Part 6: Social Media and Analytics; International audience; Social media platforms are an inexpensive communication medium help to reach other users very quickly. The same benefit is also utilized by some mischievous users to post objectionable images and symbols to certain groups of people. This types of posts include cyber-aggression, cyberbullying, offensive content, and hate speech. In this work, we analyze images posted on online social media sites to hurt online users. In this research, we designed a deep learning based system to classify aggressive post from a non-aggressive post containing symbolic images. To show the effectiveness of our model, we created a dataset crawling images from Google search to query aggressive images. The validation shows promising results.

Part 6: Social Media and Analytics; International audience; Social media plays an important role in the digital transformation of businesses. This research provides a comprehensive analysis of the use of social media by b2b companies. The current study focuses on a number of aspects of social media such as: the effect of social media; social media tools; social media use; adoption of social media use and its barriers; social media strategies; and measuring the effectiveness of the use of social media. This research provides a valuable synthesis of the relevant literature on social media in the b2b context by analysing and discussing the key findings from existing research on social media. The findings of this study can be used as an informative framework on social media for both academics and practitioners.

International audience

Part 1: Technology Adoption, Diffusion and Ubiquitous Computing; International audience; The use of smartphones has become more prevalent in light of the boom in Internet services and Web 2.0 applications. Mobile stores (e.g., Apple’s App Store and Google Play) have been increasingly used by mobile users worldwide to download or purchase different kinds of applications. This has prompted mobile app practitioners to reconsider their mobile app stores in terms of design, features and functions in order to maintain their customers’ loyalty. Due to the lack of research on this context, this study aims to identify factors that may affect users’ satisfaction and continued intention toward using mobile stores. The proposed model includes various factors derived from information systems literature (i.e., usefulness, ease of use, perceived cost, privacy and security concerns) in addition to the dimensions of mobile interactivity (i.e. active control, mobility, and responsiveness). The study sets out 13 hypotheses that include mediating relationships (e.g., perceived usefulness mediates the influence of ease of use, active control, responsiveness and mobility; perceived ease of use mediates the influence of active control). As well as outlining the proposed research method, the research contributions, limitations and future research recommendations are also addressed.

Touchscreens are the predominant medium for interactions with digital services; however, their current fixed form factor narrows the scope for rich physical interactions by limiting interaction possibilities to a single, planar surface. In this paper we introduce the concept of PickCells, a fully reconfigurable device concept composed of cells, that breaks the mould of rigid screens and explores a modular system that affords rich sets of tangible interactions and novel across-device relationships. Through a series of co-design activities – involving HCI experts and potential end-users of such systems – we synthesised a design space aimed at inspiring future research, giving researchers and designers a framework in which to explore modular screen interactions. The design space we propose unifies existing works on modular touch surfaces under a general framework and broadens horizons by opening up unexplored spaces providing new interaction possibilities. In this paper, we present the PickCells concept, a design space of modular touch surfaces, and propose a toolkit for quick scenario prototyping.

Low threshold coherent emission at 1.5 &micro, m is achieved using Er3+-doped dielectric 1D microcavities fabricated with a Radio Frequency-sputtering technique. The microcavities are composed of a half-wavelength Er3+-doped SiO2 active layer inserted between two Bragg reflectors consisting of ten, five, and seven pairs of SiO2/TiO2 layers, also doped with Er3+ ions. The morphology of the structure is inspected using scanning electron microscopy. Transmission measurements show the third and first order cavity resonance at 530 nm and 1.5 &micro, m, respectively. The photoluminescence measurements are obtained using the optical excitation at the third order cavity resonance using a 514.5 nm Ar+ laser or Xe excitation lamp at 514.5 nm, with an excitation angle of 30&deg, The full width at half maximum of the emission peak at 1535 nm decreased with the pump power until the spectral resolution of the detection system was 2.7 nm. Moreover, the emission intensity presents a non-linear behavior with the pump power and a threshold at about 4 &micro, W.

International audience; The notion of multi-layer networks introduces a general framework and common vocabulary for existing ideas in complex network theory. In doing so, it is possible to understand and compare these dierent ideas in a new and more fruitful manner. However, to make this operationalizable to the visualization and visual analytics community, we need more clarity. For example: What is a layer? What are the semantics of interlayer edges, and specifically, identity links between layers? Can dierent multilayered networks be expressed or implemented in the same way? And vice versa, can one multilayered network be expressed or implemented in dierent ways?

International audience; All Er3+ doped dielectric 1-D microcavity was fabricated by rf sputtering technique. The microcavity was constituted by half wave Er3+ doped SiO2 active layer inserted between two Bragg reflectors consists of ten pairs of SiO2/TiO2 layers also doped with Er3+ ions. The scanning electron microscopy was used to check the morphology of the structure. Transmission measurements confirm the third and first order cavity resonance at 530 nm and 1560 nm, respectively. The photoluminescence measurements were obtained by optically exciting at the third order cavity resonance using 514.5 nm Ar+ laser with an excitation angle of 30°. The Full Width at Half Maximum of the emission peak at 1560 nm decrease with the pump power until the spectral resolution of the detection system of ∼1.0 nm. Moreover, the emission intensity presents a non-linear behavior with the pump power and a threshold at about 24 mW was observed with saturation of the signal at above 185 mW of pump power.