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Coordination Communicative dans les Interactions Enfant-Parent
No full textCommunication is a complex task requiring interlocutors to simultaneously coordinateon multiple levels. This ability to coordinate communication goes hand-in-handwith a child’s ability to acquire language since social interactions play a crucial role inlanguage acquisition. Furthermore, it also plays an important role in the overall sociocognitivewell-being of the child. Research on the development of communicativecoordination in children has been traditionally based on small-scale observationalstudies or on controlled experimental studies in lab environments. We believe that inaddition to these studies, more large-scale quantitative studies based on naturalisticdata are required for amore comprehensive understanding of communicative coordinationin children. We argue that the arrival of the recent “Artificial Intelligence (AI)Spring” has provided us with new and powerfulMachine Learning (ML) models thatcan be leveraged for amore ecologically valid quantitative study of the developmentof communicative coordination in children.To test this theory, in this thesis, we study communicative coordination in childcaregiverinteractions on three different levels, namely: i) turn-taking management,ii) dialog coherence and iii) conversational grounding with the help of ML models.We utilize ML models as a tool to automatically annotate a large corpus for variouscoordinative phenomena thereby allowing us to conduct a large-scale bottom-upstudy of the development of those phenomena in child-caregiver interactions. This approachenabled us to delineate the communicative landscape of early child-caregiverinteractions in terms of their communicative intents and coherence. It also led to thediscovery that caregivers take the opportunity to repair misunderstandings in verylimited cases during child-caregiver interactions. We also found that children understandthe basic notion of turn-taking fairly early in their childhood. We also use MLmodels for computationally modelingmechanisms like turn-taking in child-caregiverinteractions. With this approach we find evidence of adult-like turn-taking behaviorin children in their middle-childhood.The various insights obtained from our studies are the initial exploratory stepstowards showcasing howML can be leveraged for a comprehensive and ecologicallyvalid large-scale study of the development of communicative coordination in children.La communication est une tâche complexe qui exige des interlocuteurs une coordinationsimultanée à plusieurs niveaux. Cette capacité à coordonner la communicationva de pair avec la capacité de l’enfant à acquérir le langage, puisque les interactionssociales jouent un rôle crucial dans l’acquisition du langage. En outre, elle joue unrôle important dans le bien-être socio-cognitif global de l’enfant. La recherche sur ledéveloppement de la coordination communicative chez les enfants est traditionnellementbasée sur des études d’observation à petite échelle ou sur des études expérimentalescontrôlées en laboratoire. Nous pensons qu’en plus de ces travaux, des étudesquantitatives à plus grande échelle basées sur des données naturelles sont nécessairespour une compréhension plus complète de la coordination communicative chez lesenfants. Nous soutenons que l’arrivée du récent "printemps de l’intelligence artificielle"nous a fourni de nouveaux et puissantsmodèles d’apprentissage automatique(ML) qui peuvent être exploités pour une étude quantitative plus écologiquementvalide du développement de la coordination communicative chez les enfants.Pour tester cette théorie, nous étudions dans cette thèse la coordination communicativedans les interactions enfant-parent à trois niveaux différents, à savoir : i) lagestion du tour de rôle, ii) la cohérence du dialogue et iii) l’ancrage conversationnel àl’aide de modèles deML. Nous utilisons les modèles deML comme outil pour annoterautomatiquement un large corpus contenant divers phénomènes de coordination,ce qui nous permet de mener une étude à grande échelle du développement de cesphénomènes dans les interactions enfant-parent. Cette approche nous a permis dedélimiter le paysage communicatif des premières interactions entre l’enfant et leparent, en termes d’intentions communicatives et de cohérence. Elle a égalementconduit à la découverte que les parents saisissent rarement l’occasion de réparerles malentendus lors de ces interactions. Nous avons également constaté que lesenfants comprennent la notion de base du tour de rôle assez tôt dans leur enfance.Nous utilisons également les modèles deML pour modéliser informatiquement desmécanismes tels que le tour de parole dans les interactions enfant-parent. Avec cetteapproche, nous trouvons des indices d’un comportement de prise de tour similaire àcelui des adultes chez les enfants en milieu d’enfance.Les différents résultats issus de nos études constituent des étapes exploratoires initialesvisant à montrer comment l’apprentissage automatique peut être mobilisé pourune étude à grande échelle, complète et écologiquement valide du développement dela coordination communicative chez les enfants
Eukaryote‐wide distribution of a family of longin domain‐containing GAP complexes for small GTPases
No full textInternational audienceArf and Rab family small GTPases and their regulators, GTPase‐activating proteins (GAPs) and guanine nucleotide exchange factors (GEFs), play a central role in membrane trafficking. In this study, we focused on a recently reported GAP for Arf (and potentially Rab) proteins, the CSW complex, a part of a small family of longin domain‐containing proteins that form complexes with GAP activity. This family also includes folliculin and GATOR1, which are GAPs for the Rag/Gtr GTPases. All three complexes are associated with lysosomes and play a role in nutrient signaling, the latter two being directly involved in the mTOR pathway. The role of CSW is not clear, but in addition to having GAP activity on Arf proteins in vitro, its mutation causes severe neurodegenerative diseases. Here we update the reported pan‐eukaryotic presence of folliculin and GATOR1, and demonstrate that CSW is also found throughout eukaryotes, though with sporadic distribution. We identify highly conserved motifs in all CSW subunits, some shared with the catalytic subunits of folliculin and GATOR1, that provide new potential avenues for experimental exploration. Remarkably, one such conserved sequence, the “GP” motif, is also found in structurally related longin proteins present in the archaeal ancestor of eukaryotes
Global Warming and the Spread of the Introduced Jellyfish Cassiopea andromeda : Thermal Niche and Habitat Suitability in the Mediterranean Sea
No full textInternational audienceClimate change affects marine ecosystems in multiple ways, including sea warming and changes in biological community structure and diversity. The Mediterranean Sea has emerged as one of the most vulnerable regions, also because of the diverse patterns of introduction of non‐native species. First recorded in the coastal waters of Cyprus in 1903, the Red Sea jellyfish Cassiopea andromeda (Forskål, 1775) is spreading its distribution and local abundance, posing questions on its potential ecological implications. Here we identified the thermal tolerance, habitat suitability, and potential distribution range of the C. andromeda polyps, a key life cycle stage responsible for asexual reproduction and population persistence. By laboratory‐controlled respirometric measurements, we assessed that the polyps of C. andromeda exhibit their optimal metabolic performances at high water temperatures, but they are tolerant to winter conditions across the Mediterranean basin. Combining experimental respiration measurements with modelling approaches enabled the definition of the species' fundamental thermal niche, with an optimal seawater temperature at 35.7°C and critical limits at 6.4°C (minimum) and 39°C (maximum). Trait‐based thermal habitat suitability maps indicated a future increase of favourable habitats for the species under warming conditions according to the Representative Concentration Pathways (RCP 4.5 and 8.5 for 2050) in Mediterranean coastal areas. In the context of climate change scenarios, the rise of seawater temperature may enable polyps to thrive across a wider geographic range, predicting a westward and northward enlargement of C. andromeda populations in the Mediterranean Sea
Exploration du RAG pour la génération de réponses à des questions en contexte éducatif: étude sur les données SCIQ
No full textNational audienceLes systèmes basés sur le RAG (Retrieval-Augmented Generation) sont des systèmes qui optimisent la puissance des grands modèles de langue (LLM, en anglais, Large Language Models) avec une recherche d'information (RI) à partir de sources de connaissances externes, sans avoir besoin de réentraîner le modèle. Ce type d'approche est connu pour améliorer les réponses du LLM, en particulier pour répondre à des questions spécifiques à un domaine, et réduire le phénomène d'hallucination constaté avec ces derniers. Dans cet article, nous explorons l'application d'un tel système dans un contexte pédagogique, en utilisant le jeu de données SCIQ (SCIence Questions), un ensemble de questions scientifiques à choix multiples de niveau scolaire, qui nous permet d'évaluer la capacité des modèles à fournir des réponses précises, pédagogiques et vérifiables. Nous évaluons les performances du système par rapport à un modèle génératif standard (Llama3 8b et Mistral 7b) de réponse aux questions et analysons ses forces et ses limites dans un contexte éducatif. La performance la plus élevée en termes de précision a été enregistrée avec l'approche basée sur le RAG (rag-llama), qui a permis d'atteindre une précision globalement supérieure par rapport aux autres approches testées
Le bateau de Thésée : Comment les professionnels naviguent-ils entre longévité et modernité de la marque ?
No full textInternational audience- Research objectives: This research aims to understand how marketing and design professionals visually reconcile representations of longevity and modernity when undertaking a packaging redesign. Methodology: The three-phase study adopts a mixed-methods approach, combininginterviews, a questionnaire, and a content analysis of redesign cases. Results: The findings provide a detailed account of designers’ work and illustrate how marketers evaluate and interpret this design work.- Managerial Implications: Conceptual and managerial implications: These results enhance understanding of brand identity management over time and offer managerial recommendations based on concrete visual actions.- Originality: This research draws on the theoretical framework of marketing-as-practice to examine how marketers and designers practically balance perceptions of longevity and modernity during packaging redesign.ObjectifsCette recherche a pour objectif de comprendre comment les professionnels du marketing et du design concilie visuellement les représentations de longévité et modernité lors de la refonte ou redesign du packaging.MéthodologieL’enquête en trois phases suit une approche de méthodes mixtes combinant des entretiens, un questionnaire et une analyse de contenu de cas de redesign.RésultatsLes résultats fournissent un compte rendu détaillé du travail des designers et montrent comment les marketeurs évaluent et interprètent ce travail de design.Implications managérialesCes résultats enrichissent les connaissances sur la gestion de l’identité de marque dans le temps et propose des recommandations managériales basées sur des actions visuelles concrètes.OriginalitéCette recherche s’appuie sur le cadre théorique du « marketing-comme-pratique » pour étudier comment marketeurs et designers équilibrent concrètement les perceptions de longévité et modernité lors du redesign de pack
L'annonce du confinement en mars 2020 dans les discours politiques, médiatiques et citoyens : Genres, dispositifs et positionnements
No full textFrom 2019, covid-19 quickly spread to a large part of the planet. In March 2020, France, Spain and England announced restrictions aimed, among other things, at confining the population. This work is in the field of language sciences, in the field of discourse analysis and using tools such as enunciation and dialogism. The analysis of the political discourse of these three European countries aimed at announcing the lockdown highlights the similarities and specificities of Emmanuel Macron's discourse in order to secondly, to understand the reactions of civil society (media and citizens) to this speech. The media comment on the President's speech but also use his words to pass on the restrictions, combining information and dramatisation. The general convergence of political and journalistic discourse in March 2020 is due to the need to inform, but also to protect and reassure a population shocked by a completely unprecedented situation: a global pandemic and travel restrictions. Citizens, for their part, although sometimes informing each other, are seizing on the discourse to talk about themselves, give their opinion and play down the situation. The day after the announcement of the lockdown in France, we note the almost total alignment of civil society and political staff with government decisions. The limited heterogeneity of citizens' discourses seems to mirror the unidirectional nature of what politicians and the media have to say.Dès 2019 le covid-19 gagne rapidement une bonne partie de la planète. En mars 2020 la France, l’Espagne et l’Angleterre annoncent des mesures de restrictions visant, entre autres, à confiner la population. Ce travail s'inscrit en sciences du langage, dans le champ de l'analyse du discours et mobilise, entre autres, les outils de l’énonciation et du dialogisme. L’analyse dans un premier temps des discours politiques de ces trois pays européens visant à annoncer le confinement met en exergue les similitudes et les spécificités du discours d’Emmanuel Macron afin de comprendre, dans un second temps, les réactions de la société civile (médias et citoyens) à ce discours. Les médias commentent le discours du chef de l’État mais aussi s’appuient sur ses propos pour transmettre les restrictions en associant information et dramatisation. La convergence assez générale des discours politiques et journalistiques de mars 2020 est due à la nécessité d’informer, mais aussi de protéger et de rassurer une population choquée par une situation complètement inédite : la pandémie mondiale et la restriction des déplacements. Les citoyens, quant à eux, bien qu’ils s’informent parfois les uns les autres, s’emparent du discours pour parler d’eux, donner leur avis et dédramatiser la situation. On note ainsi au lendemain de l’annonce du confinement en France l'alignement presque total de la société civile et du personnel politique sur les décisions gouvernementales. La faible hétérogénéité des discours citoyens semble être le miroir de la dimension unidirectionnelle des prises de parole des politiques et des médias
A Robust Framework for Integrating Supply Chain Network Design and Assembly Line Balancing Under Uncertainty
No full textInternational audienceThis paper presents a mixed-integer linear programming model, integration of designing supply chain network with assembly line balancing. The model simultaneously addresses strategic and tactical decision-making, optimizing supply chain performance while managing costs and risks. It incorporates Conditional Value at Risk to account for demand uncertainties, ensuring resilience against worst-case scenarios. The supply chain configuration includes suppliers, manufacturers, assemblers, and collection centers, with tasks assigned to straight assembly lines, respecting precedence relationships and capacity constraints. Computational results demonstrate the model’s effectiveness in minimizing total costs and achieving robust performance across multiple demand scenarios. Sensitivity analyses highlight the tradeoffs between cost efficiency and risk aversion, providing decision-makers with valuable insights into balancing resilience and operational efficiency
Modèle de rapport, Modèle préparatoire aux Assemblées de la Terre, Destiné à être communiqué aux autres Assemblées de la Terre nationales
No full textInvestigation of the influence of manganese on the dynamic strain ageing of ferritic steels – Part II: Industrial alloy
No full textInternational audienceDynamic strain aging (DSA) was studied in an as-welded C-Mn steel at multiple scales, using macroscopic tensile tests, in-situ TEM tensile tests and atom probe tomography (APT). At the macroscopic scale, DSA is related to an increase in Ultimate Tensile Strength (UTS) between 423 K and 623 K, compared to room temperature. PLC serrations are observed in a limited temperature range, 423 K and 473 K. At the nano-scale, DSA manifests as a change in dislocation dynamics, namely the occurrence of dislocation bursts. Interestingly, high-temperature diffusion-controlled (HTDC) Peierls glide suppresses PLC serrations, and its velocity controls the end of DSA. Moreover, the occurrence of HTDC-Peierls glide suggests that interstitial atoms control DSA in the C-Mn weld, that being confirmed by the extracted activation energy for HTDC-Peierls glide and by APT characterizations showing the absence of Mn on dislocations. Contrary to what was observed in the Fe-3Mn-C model in the first part of this study, Mn does not influence DSA in this industrial C-Mn weld. We propose that the reduced Mn content does not lead to a sufficient anchoring of mixed dislocations, thus allowing for the occurrence of HTDC-Peierls glide. Consequently, screw dislocations, which do not attract Mn atoms, become prominent as deformation proceeds, therefore suppressing the Mn-controlled DSA. Based on these findings, we discuss previously published results regarding the manifestations of DSA in steels as a function of their chemical composition.</div
Analysis of preparatory directional solidification experiments for a new X-ray facility for the International Space Station
No full textInternational audienceIn the last decade, the use of X-ray radiography has been adapted to the study of solidification aboard microgravity platforms such as sounding rockets and parabolic flights. However, the limited microgravity duration accessible via these platforms is not sufficient to reach steady-state conditions. The European Space Agency (ESA) is currently developing a facility for the International Space Station (ISS) to overcome this limitation. Unlike the other microgravity platforms, XRF (X-Ray Facility) will enable multiple experiments so that statistical variations can be studied, and the principal parameters varied by design. The present contribution reports recent experimental investigations carried out on Earth using the "Experiment Unit 1" (EU-1) dedicated to the study of the directional solidification of aluminium alloys. While the objective of these activities was to validate the technical performance of the set-up, preliminary scientific insights were also gained. Information on the temperature field and grain structure formation is derived from analyses of image sequences and the possibilities offered by this new device are presented and discussed.</div