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Frame of Reference: Addressing the Challenges of Common Ground Representation in Situational Dialogs
No full textThis work was granted access to the HPC resources of IDRIS under the allocation AD011016333 made by GENCI.Common ground plays a critical role in situated spoken dialogs, where interlocutors must establish and maintain shared references to entities, events, and relations to sustain coherent interaction in a shared space and over time. With the increasing presence of embodied conversational agents and social robots, the ability to correctly ground this kind of conversational content in order to refer back later also becomes important for dialog systems. Prior studies have demonstrated that LLMs are capable of performing certain grounding acts like acknowledgments. However, relatively little work has investigated their capacity to leverage the grounded information, like in complex scenarios involving space and time (e.g., "let's go to that café near the park we went to yesterday"). To that end, in this work, we evaluate a model's ability to establish common ground by utilizing these "relational references" in the dynamic and shared environments of situated dialogs. We then test multiple methods for representing common ground and further propose approaches to improve their performance by using reinforcement learning on our synthetically generated dialog data
An Exploration of the Breast Milk Nutriome, Exposome and Microbiome and their Links to Early Growth in Preterm Infants
No full textInternational audienceBackground: Breastfeeding promotes improved growth and development in preterm infants, yet the mechanisms underlying these benefits remain unclear.Objective: This study explored the interplay of breast-milk nutritional, microbiological, and environmental chemical exposure on early preterm infant growth.Methods: In the prospective LACTACOL-cohort, growth was assessed in 137 exclusively breastfed preterm infants (including 40 twins) using Z-scores of discharge weight and fat-free mass (FFM, by air-displacement plethysmography). Breast-milk samples were analyzed for their nutriome (targeted and untargeted metabolomic and lipidomic profiling), exposome (targeting persistent organic pollutants, POPs), and microbiome (16s rRNA-sequencing). Correlation analysis and sequential random forest modelling were applied to integrate multi-omics datasets and identify determinants of discharge weight Z-score (36 observations) and FFM (21 observations).Results: The nutriome emerged as the primary contributor to the postnatal growth in preterm infants. Choline-containing lipids (sphingolipids, phosphatidylcholines and their plasmalogen forms), positively contributed to weight Z-score. Sphingomyelin enriched in nervonic acid supported positively FFM Z-score, whereas oxylipins had a negative effect. The exposome exhibited complex effects: the dioxin-like compound 1,2,3,7,8-PeCDD negatively impacted weight, while the polychlorinated biphenyl 123 positively influenced both weight and lean mass gains. Brominated flame retardants were associated with a lower FFM Z-score. Although the microbiome showed an overall minor impact, it varied with POPs and postnatal growth terciles, highlighting the co-dependencies between milk components.Conclusions: This integrative hypothesis-generating pilot study provides novel evidence on the richness of breast-milk composition and the interplay of nutriome, exposome, microbiome in breast-milk and their joint influence on postnatal growth in preterm infants.Clinical trial registry: LACTACOL, ClinicalTrials.gov ID NCT NCT01493063 https://clinicaltrials.gov/study/NCT01493063
Assessing Graph Neural Networks for latency and power consumption prediction in application mappings on multicore architectures
No full textInternational audienceAccurately estimating the latency and power consumptionof software applications deployed on multicore systems remains a majorchallenge for early-stage optimization, as existing methods typically relyon slow and resource-intensive simulations. This paper explores modelingapplication-to-architecture mappings as heterogeneous graphs and investigatesGraph Neural Networks (GNNs) for predicting their performance.Four GNN models are evaluated across eleven datasets, considering fiveNeural Network-based software applications. The two best models achievemean absolute percentage errors of about 2% for power prediction and 15%for latency, with prediction times of only a few tens of milliseconds. Theseresults indicate the potential of GNN-based prediction as an efficient alternativeto simulation-driven estimation, paving the way for early-stageAI-assisted mapping optimization
Une approche archéologique et géographique du paysage maritime : l'exemple de la baie de Bourgneuf (côte atlantique, Pays de la Loire)
No full textInternational audienceThe Bay of Bourgneuf, an old Bay in Brittany, represents a continuum between land and ocean which is marked by human actions and occupations of this territory from the beginning to nowadays. It also appears as a vast maritime complex combining mooring areas, ports and inland waterways interconnected with former islands that have now disappeared. To understand this complex maritime landscape of the Bay of Bourgneuf, with no break between land and sea, it is necessary to focus on societal and environmental dynamics in the long term. The cross approach between archeology and geography thus allows us to address questions related to the evolution of the coastline, the formation of islands and the different types of human occupation on the coast. This interdisciplinary approach offers a global vision of the transformations, occupations and uses of both coastal areas and the maritime domain. This multidisciplinary study makes it possible to lay the first milestones of a joint work relating to the observation of land/sea interactions on a portion of an oceanic territory in an Atlantic-North context. After a brief introduction, we detail the geo-historical framework of the land under study, the history of research to build a new approach combining maritime archeology and geography, present the documentation and finally the first reflections of this multidisciplinary approach. A diachronic study of this bay, from prehistory to the pre-industrial period, with no break between land and sea, appeared relevant to document both its heritage and a landscape shaped by man and his activity. If studying old maps enables us to trace the evolution of the coastline in detail over the last three hundred years, the technique of sedimentological coring makes it possible to estimate the evolution of the coastal landscape during older periods. It also highlights the major paleo-environmental changes that have occurred over the past millennia. From a series of sedimentological cores, we are therefore trying to detect these marine horizons in the deepest strata of the ground. Once the coring has been carried out, the sedimentological analyzes will permit to finely characterize the origin of all the layers detected in the cores. They highlight the characteristic sea levels likely to testify to the historical evolution of the coastline. These observations are then compared with archaeological data from the Neolithic period to the 1850s, as well as nautical charts and representations of the coast documented since the 16th century. This bay and its surroundings currently form a vast maritime complex combining agricultural and oyster farming areas and protected natural areas. It was in the past a dense navigation area made up of moorings in the open sea, ports and inland waterways thanks to a network of channels and channels interconnected with islands that have now disappeared, because they are attached to the mainland.La baie de Bourgneuf représente un continuum entre la terre et l’océan marqué par la main de l’homme depuis les premières occupations de ce territoire jusqu’à nos jours. Elle apparaît également comme un vaste complexe maritime associant des zones de mouillages, des ports et des voies navigables intérieures interconnectées à d’anciennes îles aujourd’hui disparues. Pour appréhender ce paysage maritime complexe de la baie de Bourgneuf, sans rupture entre la terre et la mer, il est nécessaire de s’intéresser aux dynamiques sociétales et environnementales sur le temps long. L’approche croisée entre archéologie et géographie nous permet d’aborder les questions liées à l’évolution du trait de côte, à la formation des îles et aux formes de l’occupation humaine sur le littoral. Cette interdisciplinarité offre une vision globale des transformations, des occupations et des usages tant des espaces côtiers que du domaine maritime. Cet article permet de poser les premiers jalons d’un travail collectif relatif à l’observation des interactions terre / mer sur une portion d’un territoire océanique en contexte atlantique-nord. Après une brève introduction, nous détaillons le cadre géohistorique du terrain d’étude, l’historique des recherches pour construire une nouvelle approche associant archéologie maritime et géographie, la documentation exploitée et enfin les premières réflexions sur ce travail interdisciplinaire
: Suivi qualitatif du recours au Contrat d’engagement jeune
No full textLe Contrat d’engagement jeune (CEJ), initié en mars 2022, s’adresse aux jeunes de 16 à 25 ans en difficulté d’insertion sociale et professionnelle. Mis en œuvre par les Missions locales et par France Travail, il combine un accompagnement « intensif » par une conseillère et une allocation mensuelle, conditionnés à la réalisation de 15 à 20 heures d’activités hebdomadaires. Il a fait l’objet d’une enquête sociologique, dont les résultats et analyses font l’objet de ce rapport, menée entre octobre 2023 et mai 2025. Elle repose sur 223 entretiens et 74 séquences d’observation dans onze territoires aux caractéristiques variées. Elle explore les usages du CEJ, le travail des conseillères, et les effets du dispositif sur les structures du service public de l’emploi.Succédant à la Garantie jeunes dans un contexte post-Covid marqué par une précarité juvénile et des débats sur l’ouverture du RSA aux moins de 25 ans, le CEJ est présenté comme plus « intensif » que les dispositifs lui préexistant. Il introduit une obligation inédite de « 15 à 20 heures d’activités » hebdomadaires, censée responsabiliser les jeunes et répondre aux critiques d’« assistanat ». Il est mis en œuvre par les Missions locales et France Travail. Son déploiement contribue aussi à réorganiser les politiques d’insertion : les Missions locales, historiquement en charge de ce public, l’ont perçu comme une mise en concurrence avec France Travail.Le CEJ a accéléré des transformations déjà engagées dans les Missions locales : intensification des tâches administratives, montée en puissance du management, rationalisation et division horizontale du travail. Les conseillères, majoritairement des femmes issues des classes populaires ou moyennes, revendiquent une « fibre sociale », et investissent l’écoute et le soutien relationnel dans leur relation avec les jeunes. Elles valorisent le lien de confiance qu’elles nouent avec eux et elles, et dénoncent la surcharge administrative et parfois les tensions liées au contrôle des activités. Elles jugent le CEJ de manière ambivalente en ce que d’une part, il permet de renforcer le travail relationnel, en raison de l’intensité des rencontres qu’il suppose et de sa logique contractuelle, mais que d’autre part, il génère une surcharge de travail administrative décrite comme un facteur majeur d’empêchement du travail.Les bénéficiaires du CEJ sont majoritairement issu·es des classes populaires précarisées, cumulant souvent instabilité économique, sociale, scolaire et psychique. Ils décrivent un rapport à l’école et au marché du travail marqué par des orientations subies, des emplois précaires et des expériences dévalorisantes. Au regard de leurs conditions de vie et de leurs projets, le CEJ est un soutien important, traduit par une aide financière et l’accompagnement d’une conseillère, mais il reste temporaire et apporte rarement une réponse structurelle à leurs difficultés.Enfin, le CEJ poursuit une logique d’adaptation des jeunes aux opportunités locales de travail ou de formation. L’exigence des « 15 à 20 heures d’activités » est son innovation majeure, mais son interprétation varie selon les territoires et les conseillères, alimentant des jugements normatifs sur la légitimité des activités. L’allocation, à la fois ressource vitale et objet de contrôle moral, cristallise les tensions entre aide sociale et contrepartie. Le CEJ semble ainsi illustrer une tendance au renforcement du contrôle et de la responsabilisation, déséquilibrant le principe des droits et devoirs dans les politiques d’insertion
Les troubles du comportement possiblement causés par une thérapie : quel traitement contentieux ?
No full textInternational audienceDopaminergic medications can cause perceptual and behavioral disorders. Although the medical literature took some time to fully acknowledge this issue, it is now clearly established. In 2025, one might expect that over two decades of medical knowledge would have mitigated the risk—prompting healthcare professionals to exercise particular vigilance and enabling patients to anticipate it effectively. Yet, the press still frequently reports on such problems. Consistently, a review of legal cases shows that these matters are still being brought before the courts. The initial challenge of having this side effect recognized has now given way to a new difficulty: patients must fight to have their status as victims acknowledged and to receive compensation—even when they were informed of the risks.Les médicaments dopaminergiques peuvent causer des troubles de perception et de comportement. Même si la littérature médicale a mis un certain temps à intégrer cet enjeu, elle est à présent tout à fait explicite. En 2025, on pourrait songer que plus de vingt ans de connaissance médicale auraient réduit le risque, en conduisant les professionnels de santé à une vigilance particulière et en permettant aux patients de bien l’anticiper. Or, la presse relaie encore largement ce type de problème. De manière convergente, la consultation du contentieux montre qu’il donne encore lieu aujourd’hui à saisine des juges. A la difficulté de voir reconnaître cet effet, succède à présent la difficulté pour les patients de faire admettre qu’ils sont victimes et devraient pouvoir être indemnisés, même lorsqu’ils ont été informés
Porous NaTi<sub>2</sub>(PO<sub>4</sub>)<sub>3</sub>-PVDF Composite Granules as Negolyte Boosters for Sodium-Based Redox-Targeting Flow Batteries
No full textInternational audienceRedox-Targeting Flow Batteries (RTFBs) are promising alternatives to classical vanadium-based batteries for large-scale and stationary energy storage. Typically, RTFBs are marked by higher energy densities thanks to the addition of solid boosters within aqueous systems, taking care to limit the use of critical raw materials. This work subsequently investigates the case of sodium titanium phosphate (NTP, NaTi2(PO4)3, 132.8 mAh/g) as a potential booster material for the negolyte side of aqueous RTFBs. Pure NTP and carbon-coated NTP (C-NTP) particles were synthesized and characterized by various techniques (X-ray, TEM, TGA, Raman). So-obtained NTP and C-NTP particles were found to be suitable for creating innovative porous composite boosters formed as centimeter-sized granules by dry processing. Porous composite granules with an open porosity of 65% and 50 wt % of immobilized NTP or C-NTP were successfully produced by an extrusion–dissolution process using a regular PVDF binder and PEO as a porogen agent. Subsequently, intensive electrochemical tests were performed using an innovative dual-mediator reaction system (Fe-Tiron and 2,7-AQDS). High NTP reactivity, with booster utilization rates of up to 84% of its theoretical capacity, can be achieved under flow conditions, with an increase in volumetric capacity by a factor of 1.5, from 4 Ah L–1 to 6 Ah L–1. The mediator concentration (10 – 100 mM) and the mediator/booster ratio (0.5 – 1) play key roles in NTP reactivity. The fundamental work also highlights the benefit of C-NTP, allowing higher reactivity at low mediator concentrations. The study consequently validates the potential of NTP as an interesting booster material in future RTFB applications, with its scalable extrusion–dissolution technique to create innovative porous booster granules
S4 modal sequent calculus as intermediate logic and intermediate language
No full textInternational audienceIn this short paper, we advocate for the idea that continuation-based intermediate languages correspondto intermediate logics. The goal of intermediate languages is to serve as a basis for compiler intermediaterepresentations, allowing to represent expressive program transformations for optimisation and compilation,while preserving the properties that make programs compilable efficiently in the first place, such as the“stackability” of continuations. Intermediate logics are logics between intuitionistic and classical logic in termsof provability.Second-class continuations used in CPS-based intermediate languages correspond to a classical modal logicS4 with the added restriction that implications may only return modal types. This indeed corresponds to anintermediate logic, owing to the Gödel-McKinsey-Tarski theorem which states the intuitionistic nature of themodal fragment of S4.We introduce a three-kinded polarised sequent calculus for S4, together with an operational machinemodel that separates a heap from a stack. With this model we study a stackability property for the modalfragment of S4
Bronze Age copper supply in Mediterranean France: first results from lead isotope and chemical analyses of hoarded metalwork
No full textInternational audienceCopper supply networks in southern France are analysed on the basis of a study of five hoards of metal objects dating from the end of the Early Bronze Age (c. 17th-16th BCE) to the end of the Late Bronze Age (c. 9th BCE). A total of 73 inductively coupled plasma-optical emission spectroscopy elemental analyses were performed and 48 objects belonging to the different groups that could be identified from the elemental compositions were targeted for lead isotope analysis (multicollector-inductively coupled plasma mass spectrometry). The results clearly show that the same source was used for the various objects in each hoard, but that copper from different origins was used depending on the period. This reveals evolving supply networks that can be linked to the cultural interactions observed during this period. Towards the end of the Early Bronze Age or the beginning of the Middle Bronze Age (c. 17th-16th BCE), axe-ingots were imported into southern France along the Rhone corridor. The origin of the copper from which they are made could potentially be the Vosges massif. On the other hand, one of the major contributions of this study is to have demonstrated the use of copper originating from the Southeastern Alps during a late phase of the Middle Bronze Age and up to the Late Bronze Age (c. 14th-11th BCE). A form of packaging for this Alpine copper was as pick-ingots, and it was probably in this form that it arrived in southern France. This network was interrupted around the 9th century BCE and the populations of southern France returned to the exploitation of local minerals (Cabrières-Péret district). This research highlights the link between trade networks and cultural dynamics, showing that the circulation of raw materials also helps strengthen relations between communities
Kinematic modeling and task-based design of a URRR-URR parallel mechanism for percutaneous interventions
No full textInternational audiencePercutaneous interventions, including biopsies, thermal ablations, and regional anesthesia, involve the insertion of an instrument into the patient's body to remove tissue or manage pain. In this context, the use of a robotic assistant is suitable to guide the medical gestures, leading to a more time effective intervention and better patient care. For this purpose, this paper introduces a novel URRR-URR parallel mechanism. The constraint and mobility analysis of the mechanism is performed using screw theory. A methodology for determining the solution to its Direct and Inverse Geometric Models is presented. The forward and inverse kinematic Jacobian matrices of the mechanism are then expressed. Some singularities of the mechanism are identified and illustrated. Additionally, the design problem of the parallel manipulator (PM) under study is formulated as a bi-objective optimization problem. The first objective function is expressed in terms of the condition number of the forward and inverse Jacobian matrices. The second objective function deals with the mechanism size. Lastly, the non-dominated Pareto-optimal solutions are obtained and three Pareto-optimal solutions are detailed