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Towards a Closer Patient-Caregiver Relationship by Wearable and Ambient Assisted Living Design
No full textInternational audienceThe current epidemiology of the global population highlights an increasing number of aged individuals living with decreasing autonomy. Modern societies face the significant challenge of caring for persons with various disabilities, whether in institutions or at home. Health systems are ill-prepared in terms of staffing, economics, and public policies to manage the growing population of elderly individuals. This article discusses how technology can alleviate isolated lives, reduce hazards, and enhance human relationships, particularly the physician-patient relationship. Our interdisciplinary group focuses on developing innovative technologies to be implemented in the coming decades to improve the living conditions of elderly populations
Bioproduction of 2-Phenylethanol by Yarrowia lipolytica on Sugar Beet Molasses as a Low-Cost Substrate
No full textInternational audience2-phenylethanol (2-PE) is a valuable aromatic alcohol with diverse applications in cosmetics, food, beverages, and pharmaceutical industries. Currently, 2-PE is produced either through chemical synthesis or by extraction from plant materials. However, both conventional production methods have their own limitations. Therefore, there is a need for more eco-friendly and cost-effective approaches to produce natural 2-PE. Biotechnological routes, particularly microbial fermentations, hold promise for natural 2-PE production, especially when using low-cost substrates. In this study, 2-PE was produced by de novo synthesis via the shikimate pathway, using the yeast Yarrowia lipolytica in a medium composed of sugar beet molasses (SBM) and yeast extract (YE) as carbon and nitrogen sources, respectively. A genetically engineered strain was generated, in which the SUC2 gene was transformed, expressing the invertase enzyme, enabling Y. lipolytica to efficiently utilize SBM as a cost-effective substrate. A central composite design allowed for the optimization of the concentrations of the carbon and nitrogen sources, resulting in approximately 0.71 g(2-PE)/L(culture medium). The results obtained highlight the potential of utilizing SBM as a low-cost substrate for 2-PE production, advancing biotechnological approaches in fragrance synthesis
Multibody dynamics system with energy dissipation by hardening and softening plasticity
No full textInternational audienceIn this work we present a multibody dynamics system composed of geometrically exact nonlinear beams with inelastic behavior, representing flexible system components. The main focus of the work is to introduce advanced energy dissipation models using hardening and softening plasticity into such beam models and to show how they can also recover a vibration amplitude decay typical of viscous damping. The damping model is represented by the constitutive behavior of the flexible beam element chosen as an elasto-viscoplastic response with linear isotropic hardening and subsequent softening plasticity. The formulation is cast within the mixed variational framework, where the strong embedded discontinuity is introduced into displacement/rotation fields in the softening phase leading to localized plastic deformation. We also aim to ensure model capabilities to deliver results for long-term loading simulations, which is of interest for quantifying the risk of fatigue failure for such flexible system component. The corresponding numerical implementation combines the space discretization based on the finite element method with the Ph.</div
The strong consistency and asymptotic normality of the kernel estimator type in functional single index model in presence of censored data
No full textInternational audienceIn the present study, we address the nonparametric estimation challenge related to the regression function within the Single Functional Index Model in the random censoring framework. The principal achievement of this investigation lies in the establishment of the asymptotic characteristics of the estimator, including rates of almost complete convergence. Moreover, we establish the asymptotic normality of the constructed estimator under mild conditions. Subsequently, we provide the application of our findings towards the construction of confidence intervals. Lastly, we illuminate the finite-sample performance of both the model and the estimation methodology through the analysis of simulated data and a real-world data example
Supercritical fluid technology for the formulation of quercetin with chitosan solid amorphous dispersions
No full textInternational audienc
Partitioned Linear Orders and Belief Revision
No full textInternational audienceDespite their expressive power in representing alternatives or beliefs tainted by incomparabilities, it is often difficult to use generic partial orders. Hence, various structures have been historically studied in the literature, such as weak orders, semiorders or interval orders, each capturing a different fragment of partial orders. In this article, we propose and study in detail a fragment rich enough to represent some highly intuitive patterns involving incomparable elements that cannot be captured by the aforementioned fragments: partitioned linear orders (PLOs). These structures can be viewed as split independent linear orders, each one of them representing a local totally ranked situation. Then, we show how they can be used in Katsuno-Mendelzon-style belief revision. We propose a set of postulates, a representation theorem and a family of concrete operators
Towards a Multi-Agent Deep ReinforcementLearning Approach for End-to-End LatencyMinimization in Complex CommunicationNetworks
No full textInternational audienceModern communication networks like 5G and 6G are characterized by unpredictable traffic patterns and dynamic communicationnetwork characteristics. This makes network management a particularlychallenging task. To address this problem, various Machine Learningapproaches have been investigated. Moreover, with the increasing integration of Distributed Machine Learning solutions for the emerging mobile communication networks to achieve fast decision-making operations,network management services are accommodating this paradigm shift toensure decentralized management operations. In this paper, we addressthe problem of end-to-end latency minimization in complex communication networks like 5G and future 6G networks. To achieve this goal, wepropose a Multi-Agent Deep Reinforcement Learning approach to minimize end-to-end latency by adopting a reward-based dynamic multi-pathrouting strategy. The preliminary evaluation results show that our solution presents a good performance compared to a naive approach (i.e;ML-free routing) when considering different traffic patterns
TOOTHMIMIC : minéralisation assistée par enzyme pour la conception d'émail biomimétique
No full textBiomineralization is the intricately-regulated process by which living organisms form hierarchically ordered mineralized materials. In the human body, the hard tissues are formed of calcium phosphate mineral composites with unique architectures that provide unparalleledmaterial properties. While most of the mineralized tissues, such as bone, dentin, and cementum, can be biologically reformed when damaged, the most extensively mineralized tissue, enamel, cannot. This work investigates the utility of alkaline phosphatase, one of the enzymes known to be an important biochemical regulator of mineralization kinetics in vivo, in biomimetic mineralization strategies for the design of biomineral materials with multi-order control. These enzyme-assisted mineralization strategies are combined with ionic substitution and surface science techniques to achieve localized, controlled mineralization with compositional and structural similarity to native tissues, particularly human dental enamel. The effect of ionic substitution with species such as fluoride and carbonate on the structure and morphology of crystalline hydroxyapatites synthesized by homogeneous phase enzymatic catalysis. Specifically, refinement of X-ray diffraction data and complementary characterization techniques shed light on how the mineralization solution environment may tune ionic substitution in an enzymatic system. Thorough investigation of the surface of enzymatically mineralized solids by X-ray photoelectron spectroscopy yielded important insights on how to best approach the compositional analysis of biomineral solids. Results for different series of enzymatically mineralized substituted hydroxyapatites revealed that quantification of XPS data can be heavily complicated by the non-specific adsorption of protein, adventitious contamination, and experimental design, and led to the development of best practices for approaching such experiments. With improved understanding of biomimetic enzyme-assisted mineralization for the synthesis of substituted hydroxyapatites in the homogeneous phase, surface-localized mineralization was explored by immobilizing ALP in enzyme/polyelectrolyte multilayers via layer-by-layer assembly. Fresh, catalytically active enzyme/polyelectrolyte multilayers were even built up on previously mineralized surfaces and subsequently mineralized in an iterative repetitive synthetic process. This strategy of mineralized layer seriation enabled the design of macroscale mineralized materials with molecular-scale control. Strategic modulation of the mineralization conditions to favor ionic substitution was then combined with seriation for the design of biomineral materials with structure and composition resembling native tissue, such as human dental enamel. These findings present an exciting path forward for the biomimetic design and improved characterization of biomineral surfaces and materials.La biominéralisation est le processus complexe par lequel les organismes vivants forment des matériaux minéralisés hiérarchiquement organisés. Dans le corps humain, les tissus durs sont formés de composites minéraux de phosphate de calcium avec des architectures uniques qui fournissent des propriétés matérielles inégalées. Si la plupart des tissus minéralisés, tels que l'os, la dentine et le cément, peuvent être biologiquement reformés lorsqu'ils sont endommagés, ce n'est pas le cas du tissu le plus minéralisé, l'émail dentaire. Ce travail étudie l'utilité de la phosphatase alcaline, l'une des enzymes connues pour être un régulateur biochimique important en contrôlant de la sursaturation locale d'ions de phosphate et donc la cinétique de minéralisation in vivo, dans les stratégies de minéralisation biomimétique pour la conception de matériaux biominéraux avec un contrôle d'ordre sur une gamme d'échelles. Ces stratégies de minéralisation enzymatique sont combinées à des techniques de substitution ionique et de science des surfaces afin d'obtenir une minéralisation localisée et contrôlée dont la composition et la structure sont similaires à celles des tissus natifs, en particulier l'émail dentaire humain. L'effet de la substitution ionique avec des espèces telles que le fluorure et le carbonate sur la structure et la morphologie des hydroxyapatites cristallines synthétisées par catalyse enzymatique en phase homogène. En particulier, l'affinement des données de diffraction des rayons X et les techniques de caractérisation complémentaires permettent de comprendre comment l'environnement de la solution de minéralisation peut régler la substitution ionique dans un système enzymatique. L'étude approfondie de la surface des solides minéralisés par voie enzymatique au moyen de la spectroscopie photoélectronique à rayons X a donné des indications importantes sur la meilleure façon d'analyser de la composition des solides biominéraux. Les résultats obtenus pour différentes séries d'hydroxyapatites substituées par minéralisation enzymatique ont révélé que la quantification des données XPS peut être fortement compliquée par l'adsorption non spécifique de protéines, la contamination expérimentale, et ont incité l'élaboration de meilleures pratiques pour comment approcher de telles expériences. Grâce à une meilleure compréhension de la minéralisation enzymatique pour la synthèse d'hydroxyapatites substituées en phase homogène, la minéralisation localisée en surface a été explorée en immobilisant l'ALP dans des multicouches enzyme/polyelectrolyte via un assemblage couche par couche. Des multicouches enzyme/polyelectrolyte catalytiquement actives ont même été construites sur des surfaces précédemment minéralisées et minéralisées par la suite dans le cadre d'un processus synthétique itératif et répétitif. Cette stratégie de sériation des couches minéralisées a permis de concevoir des matériaux minéralisés à grande échelle avec un contrôle à l'échelle moléculaire. La modulation stratégique des conditions de minéralisation pour favoriser la substitution ionique a ensuite été combinée à la sériation pour la conception de matériaux biominéraux dont la structure et la composition ressemblent aux tissus natifs, tels que l'émail dentaire humain. Ces résultats ouvrent la voie à la synthèse biomimétique et à la caractérisation améliorée des surfaces et des matériaux biominéraux
Influence of biochar properties on the catalytic cracking of toluene
No full textInternational audienceBiochars appear to have excellent catalytic potential for cracking tar molecules. The textural properties of biochars, such as specific surface area and pore size distribution, play a major role in the catalytic potential of these materials. The aim of this study is firstly to produce biochars with different properties using physical activation methods, and then to test these biochars in order to study the effect of their properties on toluene cracking.</div
Le numérique comme objet, le numérique comme système
No full textEn prenant le sens objectif du génitif, l’intelligibilité du numérique renvoie à la capacité d’en rendre raison, de le comprendre et de le mettre en perspective. Le génitif subjectif renverrait plutôt à ce que le numérique permet de construire ou de constituer quant à l’intelligibilité, ce qu’il permet de comprendre. Comprendre le numérique, comprendre par le numérique, constituent les deux clés d’entrée de ce numéro