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Urine flow cytometry in older adults urinary tract infection diagnosis: is it time to reevaluate thresholds for men and women?
No full textInternational audienc
Optimization and Multi-Model Approaches for Maximizing Ship Decarbonization
No full textInternational audienceAligned with the International Maritime Organization's (IMO) aim to lower greenhouse gas emissions, the use of Wind-Assisted Ship Propulsion (WASP) in maritime transport is gaining increased attention. The study and optimization of WASP remain challenging due to complex physics and the high number of parameters involved. This includes interactions between aerodynamics, hydrodynamics, and structural dynamics, which require advanced multi-physics modeling. Additionally, numerous factors must be optimized, from design and control parameters to route selection, all within the variable maritime environment. Addressing these challenges demands multi-model approaches and multi-criteria optimization methods to maximize energy efficiency effectively. In this context, the laboratories of Ecole Navale, IFREMER, ENSM, and ENSTA Bretagne are collaborating on several research projects, with a selection of two thematic studies presented here.The first study is carried out as part of the SHIVA and SAWASP projects, jointly led by Ecole Navale, IFREMER and ENSTA Bretagne. The goal of these projects is to optimize the hydrodynamic performance of innovative, fully electric, Vertical-Axis Propellers (VAPs) and their optimal use in conjunction with a wind-assisted ships. To achieve this, the SHIVA project implements a multi-criteria optimization of the propeller blade-pitching laws, utilizing multi-fidelity numerical and experimental surrogate models. These optimizations enable the determination of a set of optimal pitch laws for different operating points of the propeller. In the SAWASP project, a 6-meter wind-assisted ship equipped with VAPs is developed to study the optimal aerodynamic-hydrodynamic coupling. In particular, the energy gains from using VAPs as the main propulsion system, generating a lateral anti-drift force, are studied. The use of Reinforcement Learning (RL) methods to maintain optimal ship operation performance at sea, as an uncertain environment, is also part of this project.The second study is conducted within the framework of the SOMOS project, jointly managed by ENSM and ENSTA Bretagne. The project's goal is to create and validate a set of numerical tools, that allow for rapid and precise assessment of the energy efficiency of wind-assisted ships. For the purposes of this study, a modular and comprehensive ship motion solver is formulated as an optimal control optimization problem, to evaluate, compare, and optimize energy performance. Such an approach is very complex to implement and, depending on the fidelity-level used, may require very high modeling costs. This is why most research efforts focus on specific aspects of the broader problem, often overlooking the coupling of maritime routing, ship motion analysis, and the optimization of control parameters along the planned sea route. The present work provides an innovative approach for the calculation of optimized trajectories for wind-assisted ship, by both considering the ship's maneuvering capabilities and the optimization of ship control and/or design parameters. In contrast to conventional routing methods, the proposed approach achieves high computational efficiency and relies on direct multiple shooting methods to determine optimal ship control parameters (RPM, rudder angle, etc.) and design variables (rotor Flettner or sail positioning, rudder area, etc.) along the sea route, satisfying the constraints of complying with the ship's equations of motion
Beyond capstone: toward a new strategy for appraising and selecting emails to transfer to archives within French public agencies
No full textInternational audienceThis article introduces two new approaches to email archiving within French public agencies undertaken between 2020 and 2023 at the University of Angers (France). It shows how a qualitative survey of producers’ practices and an NLP-based tool might provide the basis for new strategies for the appraisal and selection of email boxes and messages to be transferred to archives. The initial impetus was to overcome difficulties faced by French administrative records managers and archivists in locally implementing the appraisal framework known as the “Capstone” approach, which recommends gathering emails as electronic records and preserving for the long term only specific mailboxes selected in light of the function or position of the email account owner. While Capstone was adopted at the national scale in the French administration, major archival issues remain. Does an approach that focuses on the mailboxes of individuals holding strategic job positions correspond to the reality of bureaucratic work in France? And how should one define accountable criteria for identifying and appraising emails or mailboxes to be preserved on the basis of their enduring value? To address this, we combined two sociological methods, interviews and observation, and developed an interface for classifying messages using NLP. The combination of these two yielded some crucial elements to help archivists shift from the level of a single mailbox to that of a network: a better understanding of the practices of email producers, new criteria for selecting relevant mailboxes, and a new tool for archivists to appraise email archives
Un dysfonctionnement managérial peut être constitutif de faits de harcèlement moral justifiant l'octroi de la protection fonctionnelle
No full textInternational audienceNote sous CAA Paris, 5 décembre 2024, nos 23PA00138, 23PA00139, Commune de La Courneuv
La transposition de la directive de 2005 relative aux pratiques commerciales déloyales
No full textInternational audienceLe droit de la consommation fait l’objet de nombreuses interventions par le droit de l’Union européenne. Depuis les années 2000, il le fait au moyen de la méthode de l’harmonisation totale, méthode tendant à l’uniformité des droits nationaux. La directive de 2005 relative aux pratiques commerciales déloyales est la première à prévoir expressément que toutes ses dispositions sont d’harmonisation totale. En partant du constat du défaut de transposition conforme de ce texte, l’étude nous conduit à nous intéresser aux raisons de cette défaillance et à rechercher les moyens d’y remédier. Elle permet également de discuter de la pertinence du recours aux directives d’harmonisation totale
LIMIT THEOREMS FOR BIRKHOFF SUMS AND LOCAL TIMES OF THE PERIODIC LORENTZ GAS WITH INFINITE HORIZON
No full textThis work is a contribution to the study of the ergodic and stochastic properties of Z d-periodic dynamical systems preserving an infinite measure. We establish functional limit theorems for natural Birkhoff sums related to local times of the Z d-periodic Lorentz gas with infinite horizon, for both the collision map and the flow. In particular, our results apply to the difference between the numbers of collisions in two different cells. Because of the Z d-periodicity of the model we are interested in, these Birkhoff sums can be rewritten as additive functionals of a Birkhoff sum of the Sinai billiard. Our proofs rely on a general argument valid in a general framework. For completness and in view of future studies, we state a general result of convergence of additive functionals of Birkhoff sums of chaotic probability preserving dynamical systems under general assumptions
Few-Shot Domain Adaptation for Named-Entity Recognition via Joint Constrained k-Means and Subspace Selection
No full textInternational audienceNamed-entity recognition (NER) is a task that typically requires large annotated datasets, which limits its applicability across domains with varying entity definitions. This paper addresses few-shot NER, aiming to transfer knowledge to new domains with minimal supervision. Unlike previous approaches that rely solely on limited annotated data, we propose a weakly supervised algorithm that combines small labeled datasets with large amounts of unlabeled data. Our method extends the kmeans algorithm with label supervision, cluster size constraints and domain-specific discriminative subspace selection. This unified framework achieves state-of-the-art results in fewshot NER on several English datasets
« Verre. Des religieuses en vitrine »
No full textInternational audienceIl n’existe pas d’instruction pour la fabrication des cellules ou maquettes de religieuses. Les savoir-faire se transmettent par imitation et des modèles circulent au sein des ordres. L’observation permet de repérer des usages, codifiés et constants. L’identification des éléments en verre est essentielle pour comprendre à qui s’adressent ces scènes de clôture et comment les regards sont dirigés sur l’objet. La sœur qui confectionne la boîte recherche un réalisme édifiant, prenant des libertés avec l’architecture conventuelle. L'observation fine des éléments en verre dans les cellules miniatures met en lumière les deux facettes de la cellule de religieuse, à la fois miroir de l'intériorité ascétique et séduisante vitrine publicitaire
Giant Chemo-Resistive Response of POSS Nano-Spacers in PS- and PMMA-Based Quantum Resistive Vapour Sensors (vQRS) Used for Cancer Biomarker Analysis
No full textInternational audienceThe detection of volatile organic compound (VOC) biomarkers from the volatolome for the anticipated diagnosis of severe diseases such as cancers is made difficult due to the presence of high quantities of H2O in the collected samples. It has been shown that water molecules tend to compete or combine themselves with analytes, which requires either their removal or the development of more sensitive and discriminant sensors. In this later prospect, a positive effect of poly(hedral oligomeric silsesquioxanes) (POSS) is sought out to enhance the sensitivity of carbon nanotube-based quantum resistive vapour sensors (vQRS). POSS, once copolymerized with methyl methacrylate or styrene, can be used as nano-spacers amplifying the disconnection of the nano-junctions due to swelling of the polymer upon the diffusion of VOC. The amplitude of this phenomenon, which is at the origin of the chemo-resistive behaviour of vQRS, was compared with that of homologue transducers made of poly(styrene) (PS) and poly(methyl methacrylate) (PMMA)-coated carbon nanotube (CNT) random networks. The presence of POSS in PS-based sensors has enhanced their sensitivity by 213 times for toluene, by 268 times for acetone, by 4 times for ethanol, and by 187 times for cyclohexane. Similarly, the presence of POSS in PMMA chains increases the sensitivity of sensors to cyclohexane by 10 times, to ethanol by 45 times, to toluene by 244 times, and to acetone and butanone by 4 times. All transducers were made by spray layer by layer (sLbL) to obtain a hierarchically structured conducting architecture. The transducers’ surface was characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM) to observe the CNT coating and dispersion level in the matrix. All sensors were tested with twenty-one VOC part of lung and skin cancer biomarkers by using a dynamic vapour analysis (DVA). The vQRS based on POSS copolymers demonstrated much larger chemo-resistive responses (AR) than the sensors based only on pure polymers and were found to be very selective towards cyclohexane and hexene-1. The PMMA-co-POSS/CNT sensor was able to detect down to 12 ppm of VOC with a very high signal-to-noise ratio (SNR) and to discriminate six VOC among them all with a PCA (principal component analysis) projection
Plastics used in agriculture and for food: uses, properties and impacts. Extended report of the collective scientific assessment
No full textThis document is the report of the collective scientific assessment (CSA) requested and funded by theFrench Agency for ecological transition (ADEME), the French Ministry of agriculture and foodsovereignty, and the French Ministry for the ecological transition, biodiversity, forests, marine affairs andfisheries. The report of the CSA was conducted by a group of scientific experts without prior approvalby the funders, INRAE or the CNRS