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How do positive and negative emotions influence children’s and adolescents’ arithmetic performance?
No full textInternational audienceThis study is the first to investigate how negative and positive emotional states influence children’s arithmetic performance and age-related differences therein. Children aged 8–14 ( n = 149) were asked to verify true/false, one-digit addition problems (i.e., 8 + 2 = 10. True? False?) which were superimposed on emotionally negative, positive, or neutral pictures. The main results showed that (a) both positive and negative emotions impaired children’s arithmetic performance, (b) deleterious effects of negative emotions were larger than those of positive emotions, (c) effects of emotions were modulated by the type of (true/false) problems, (d) effects of emotions on current trials were influenced by emotions on immediately preceding trials, and (e) effects of emotions as well as their trial-to-trial modulations changed with children’s age. These findings have important implications for further our understanding of effects of emotions in children’s arithmetic and how these effects change as children grow older
<i>Euclid</i>: Early Release Observations – The intracluster light and intracluster globular clusters of the Perseus cluster
No full textInternational audienceWe study the intracluster light (ICL) and intracluster globular clusters (ICGCs) in the nearby Perseus cluster of galaxies using Euclid's Early Release Observations. By modelling the isophotal and iso-density contours, we mapped the distributions and properties of the ICL and ICGCs out to radii of 200-600 kpc (up to ∼ 1 3 of the virial radius, depending on the parameter) from the brightest cluster galaxy (BCG). We find that the central 500 kpc of the Perseus cluster hosts 70 000 ± 2800 globular clusters, and 1.7 × 10 12 L ⊙ of diffuse light from the BCG+ICL in the near-infrared H E . This accounts for 38 ± 6% of the cluster's total stellar luminosity within this radius. The ICL and ICGCs share a coherent spatial distribution which suggests that they have a common origin or that a common potential governs their distribution. Their contours on the largest scales (>200 kpc) are not centred on the BCG's core, but are instead offset westwards by 60 kpc towards several luminous cluster galaxies. This offset is opposite to the displacement observed in the gaseous intracluster medium. The radial surface brightness profile of the BCG+ICL is best described by a double Sérsic model, with 68 ± 4% of the H E light contained in the extended, outer component. The transition between these components occurs at ≈60 kpc, beyond which the isophotes become increasingly elliptical and off-centred. Furthermore, the radial ICGC number density profile closely follows the profile of the ⋆ This paper is published on behalf of the Euclid Consortium.</div
Introduction
No full textNational audienceLe monde du travail connait d’importantes transformations. En témoignent par exemple, outre la pratique du télétravail, le développement du secteur de l’aide à domicile ou le boom du numérique. Nous assistons à l’émergence d’une structure sociale inédite, obligeant les sciences humaines et sociales à aborder autrement la question du travail.Santé, temporalités, rapport des jeunes au travail, généralisation des outils de gestion, délocalisation, inégalités de genre, etc. : sur toutes ces thématiques, et bien d’autres, cet ouvrage réunit parmi les meilleurs spécialistes. Ensemble, ils et elles donnent à voir les grands défis liés aux transformations du travail et la manière dont la recherche s’en saisit.Ces regards croisés entre disciplines et questions sociétales éclairent en profondeur la diversité des mondes du travail en France.Véritable état des lieux des recherches menées depuis trois décennies, cet ouvrage s’organise en deux parties : il s’intéresse d’abord à un certain nombre d’enjeux contemporains, puis rend compte de la manière dont les disciplines des sciences sociales ont contribué à enrichir nos connaissances sur le travail
Hammond Transfers and Ordinal Inequality Measurement
No full textThis article establishes a direct proof of the equivalence between two incomplete rankings of distributions of an ordinal attribute. The first ranking is the possibility of going from one distribution to another by a finite sequence of Hammond transfers. The second ranking is the intersection of two dominance criteria introduced by Gravel et al. (Economic Theory, 71 (2021), 33-80). The proof constructs an algorithm that provides a series of Hammond transfers, between any two distributions related by the intersection of the two dominances
Smooth sailing or ragged climb? -- Increasing the robustness of power spectrum de-wiggling and ShapeFit parameter compression
No full textInternational audienceThe baryonic features in the galaxy power spectrum offer tight, time-resolved constraints on the expansion history of the Universe but complicate the measurement of the broadband shape of the power spectrum, which also contains precious cosmological information. In this work we compare thirteen methods designed to separate the broadband and oscillating components and examine their performance. The systematic uncertainty between different de-wiggling procedures is at most %, depending on the scale. The ShapeFit parameter compression aims to compute the slope of the power spectrum at large scales, sensitive to matter-radiation equality and the baryonic suppression. We show that the de-wiggling procedures impart large (50%) differences on the obtained slope values, but as long as the theory and data pipelines are set up consistently, this is of no concern for cosmological inference given the precision of existing and on-going surveys. However, it still motivates the search for more robust ways of extracting the slope. We show that post-processing the power spectrum ratio before taking the derivative makes the slope values far more robust. We further investigate eleven ways of extracting the slope and highlight the two most successful ones. We derive a systematic uncertainty on the slope of by studying the behavior of the slopes in different cosmologies within and beyond CDM and the impact in cosmological inference. In cosmologies with a feature in the matter-power spectrum, such as in the early dark energy cosmologies, this systematic uncertainty estimate does not necessarily hold, and further investigation is required
L'UTILISATION DE SOUS-CULTURES PRÉCOCES POUR RÉDUIRE LE TEMPS DE MANIPULATION DE LA CULTUROMIQUE
No full textCulturomics, a high scale culture approach based on the multiplication of culture conditions, coupled with extended incubation times proved effective for discovering unknown microorganisms. While significant efforts were made to reduce the number of conditions, preliminary work suggested that strict anaerobic species do not necessarily require prolonged pre-incubation time. The aim of this study is to apply culturomics to faecal samples with one pre-incubation step, following very early and late subcultures. From the same stool specimen from a healthy donor, we first developed our rapid culturomics method by handling the sample Microbiological Safety Cabinet (MSC) and then validate our approach on the same sample but manipulated in anaerobic chamber. We used a single culture condition consisting of pre-incubation in an anaerobic blood culture bottle containing modified YCFA (Yeast Casitone Fatty Acids Agar), supplemented with blood and rumen fluid, followed by early (H0 -H24) and late (D2 -D30) subcultures. A total of 88 bacterial species were isolated during the initial experiment without anaerobic chamber, including Christensenella and Faecalibacterium species. Subculturing at H0 was the most diverse subculture time, and species considered as fastidious, including Coprococcus comes, Faecalibacterium massiliense and Ruminococcus torques, that were subcultured immediately following pre-incubation. We then reduced the less fertile subculture times by reducing their number from 15 to 8 and validated our protocol on a second aliquot from the same specimen, from which we cultured 103 bacterial species, mostly strict anaerobes. This study demonstrates that strict anaerobes do not require extended pre-incubation times. Even if our data are limited by the analysis of one single stool sample, we propose herein a rapid and effective culturomics protocol targeting anaerobes by combining early and late subculture times from one single culture condition, paving the way for high-scale culturomics studies.</div
Une industrie moustérienne à bifaces et paléolithique supérieur à Escanis, commune d'Aurillac (Cantal)
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Détection de terrasses agricoles à l'aide de l'apprentissage automatique à partir d'orthophotos et d'un modèle numérique de terrain basé sur le LiDAR : une étude de cas dans la vallée de la Roya, dans le sud-est de la France
No full textInternational audienceTerrassen haben seit langem steile Hänge in sanfte Stufen verwandelt, wodurch die Erosion verringert und die Landwirtschaft auf marginalen Flächen ermöglicht wurde. Im französischen Roya-Tal zeigten diese jahrzehntelang vernachlässigten Trockenmauerkonstruktionen während des Sturms Alex im Oktober 2020 eine bemerkenswerte Widerstandsfähigkeit. Dies veranlasste die Zivilgesellschaft und Forscher, Terrassen zu identifizieren, die die Ernährungssicherheit und Agrotourismus-Initiativen unterstützen könnten. Ziel dieser Studie war es, eine halbautomatische Methode zur Erkennung und Kartierung von Terrassenflächen zu entwickeln, die LiDAR- und Orthofotodaten aus französischen Archiven verwendet, mit GIS verarbeitet und mit einem Support-Vektor-Maschinen-Klassifizierungsalgorithmus (SVM) analysiert werden. Das Modell identifizierte 18 Terrassen mit einer Größe von mehr als 1 Hektar in Saorge und 35 in La Brigue. Feldbesuche bestätigten die Verlassenheit mehrerer Gebiete. Genauigkeitstests ergaben eine Benutzergenauigkeit (UA) von 97 % in Saorge und 72 % in La Brigue. Diese Diskrepanz spiegelt standortspezifische Unterschiede wider, darunter die Steilheit des Geländes, die Vegetationsdichte und die Datenauflösung. Diese Ergebnisse unterstreichen den Wert des maschinellen Lernens für die Kartierung von Terrassen und betonen gleichzeitig die Notwendigkeit, lokale geomorphologische Faktoren und Datenqualitätsfaktoren zu berücksichtigen, um die Modellleistung zu verbessern. Eine verbesserte Terrassenerkennung unterstützt eine nachhaltige Landbewirtschaftung, die Wiederbelebung der Landwirtschaft und die Risikominderung in Bergregionen und bietet praktische Instrumente für die zukünftige Landschaftsrestaurierung und die Planung der Ernährungssicherheit.Terraces have long transformed steep slopes into gradual steps, reducing erosion and enabling agriculture on marginal land. In France's Roya Valley, these dry stone structures, neglected for decades, demonstrated remarkable resilience during storm Alex in October 2020. This prompted civil society and researchers to identify terraces that could support food security and agri-tourism initiatives. This study aimed to develop a semi-automatic method for detecting and mapping terraced areas using LiDAR and orthophoto data from French repositories, processed with GIS and analyzed through a Support Vector Machine (SVM) classification algorithm. The model identified 18 terraces larger than 1 hectare in Saorge and 35 in La Brigue. Field visits confirmed evidence of abandonment in several areas. Accuracy tests showed a user accuracy (UA) of 97% in Saorge and 72% in La Brigue. This disparity reflects site-specific differences, including terrain steepness, vegetation density, and data resolution. These results highlight the value of machine learning for terrace mapping while emphasizing the need to account for local geomorphological and data-quality factors to improve model performance. Enhanced terrace detection supports sustainable land management, agricultural revitalization, and risk mitigation in mountainous regions, offering practical tools for future landscape restoration and food resilience planning.Les terrasses ont depuis longtemps transformé les pentes abruptes en gradins progressifs, réduisant ainsi l'érosion et permettant l'agriculture sur des terres marginales. Dans la vallée de la Roya, en France, ces structures en pierre sèche, négligées pendant des décennies, ont fait preuve d'une résilience remarquable lors de la tempête Alex en octobre 2020. Cela a incité la société civile et les chercheurs à identifier les terrasses susceptibles de soutenir la sécurité alimentaire et les initiatives d'agrotourisme. Cette étude visait à développer une méthode semi-automatique de détection et de cartographie des zones en terrasses à l'aide de données LiDAR et d'orthophotos provenant de référentiels français, traitées avec un SIG et analysées à l'aide d'un algorithme de classification par machine à vecteurs de support (SVM). Le modèle a identifié 18 terrasses de plus d'un hectare à Saorge et 35 à La Brigue. Des visites sur le terrain ont confirmé l'abandon de plusieurs zones. Les tests de précision ont montré une précision utilisateur (UA) de 97 % à Saorge et de 72 % à La Brigue. Cette disparité reflète les différences spécifiques au site, notamment la pente du terrain, la densité de la végétation et la résolution des données. Ces résultats soulignent l'intérêt de l'apprentissage automatique pour la cartographie des terrasses, tout en soulignant la nécessité de tenir compte des facteurs géomorphologiques locaux et de la qualité des données afin d'améliorer les performances du modèle. Une meilleure détection des terrasses favorise la gestion durable des terres, la revitalisation agricole et l'atténuation des risques dans les régions montagneuses, offrant des outils pratiques pour la restauration future des paysages et la planification de la résilience alimentaire
La communication interpersonnelle, source de bien-être dans les jeux vidéo multijoueurs en ligne : une étude empirique
No full textInternational audienceRecent research has established positive links between digital uses and well-being. In this context, and using semi-structured interviews with 17 gamers, this present study investigates the previously unexplored links between interpersonal oral communication in online multiplayer video games and players’ well-being, particularly in its social component. The results reveal, firstly that interpersonal oral communication in video games contributes to players’ social well-being by fostering closeness and intimacy in interpersonal relationships, thereby enhancing dimensions of social acceptance and integration. Secondly, the results also shed light on why interpersonal oral communication also improves well-being in its hedonic and psychological components.De récents travaux ont établi des liens positifs entre usages numériques et bien-être. Dans ce contexte et à l'aide d’entretiens semi-directifs menés sur 17 joueurs, la présente étude s’est intéressée aux liens, jusqu’à présent mal connus, entre la communication orale interpersonnelle dans les jeux vidéo multijoueurs en ligne et le bien-être des joueurs, notamment dans sa composante sociale. Les résultats montrent, premièrement, que la communication orale interpersonnelle dans les jeux vidéo contribue au bien-être social des joueurs en favorisant la proximité et l’intimité des relations interpersonnelles, contribuant ainsi à améliorer les dimensions d’acceptation et d’intégration sociales. Deuxièmement, les résultats permettent également de mieux comprendre pourquoi la communication orale interpersonnelle améliore également le bien-être dans ses composantes hédonique et psychologique
Iron-rich microband formation in marine sediments by hydrothermal iron cycling bacteria at Lucky Strike
No full textInternational audienceModels describing banded iron formation deposition beneath oxygenated Paleoproterozoic marine shelf waters assume that microaerophilic iron-oxidizing microorganisms were significant contributors. However, direct evidence for this mechanism is lacking, and it remains unclear how associated primary organic biomass and biogenic iron oxyhydroxides transformed into organic carbon-poor iron oxide/ carbonate-rich bands in banded iron formations. Here we explore in situ modern Zetaproteobacterial iron-oxidizing mats thriving in the Lucky Strike hydrothermal vent field to develop an empirical model that explains the potential contribution of iron-based metabolisms to deposition of rocks resembling banded iron formations. Petrographic, mineralogical, and geochemical data suggest that abundant production of Zetaproteobacterial stalks nucleates and drives spontaneous biotic/abiotic ferrihydrite precipitation in the mats. Subsequent early diagenetic anaerobic microbial oxidation of dead biomass as the mats aged, coupled to microbial reduction of iron oxyhydroxides/oxides, generates ferrous carbonates and mixed valence magnetite. Collectively, this forms crystalline iron-rich organic carbonlean 13C-depleted layers reminiscent of Precambrian banded iron formation microbands