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The cosmic web's Lyman- glow at ; varying hydrodynamic models, dust, and wide-field, narrow-band imaging detection
No full textInternational audienceThe diffuse glow of the cosmic web in Lyman- emission has long been predicted, yet remained elusive to direct wide field detection. We present theoretical calculations that, when compared with recent observations made using the Condor Array Telescope in New Mexico reported in Lanzetta et al. 2024, point to its discovery at . Synthetic Lyman- surface brightness maps are constructed from five state-of-the-art hydrodynamic simulations (Illustris-TNG, SIMBA, EAGLE, CROCODILE, and Sherwood), incorporating dust attenuation, star formation, collisional excitation, and recombination physics. Our cosmic web Lyman- surface brightness predictions are consistent with the UV excess detected at high significance in the recent deep, wide field, narrow-band imaging Condor data. The calculations presented here thus demonstrate that diffuse Lyman- emission is observable with current (and next-generation) wide field low surface brightness facilities, opening the path to direct cartographic mapping of the cosmic web. These findings mark a turning point: for the first time, cosmology moves beyond inference from absorption and high-density peaks, into panoramic imaging of the faint intergalactic scaffolding that underpins structure formation in the Universe
Challenges of work in agriculture: a gender-informed analysis through the narratives of new entrants into organic farming
No full textInternational audienceThis article examines work in agriculture by a gender-informed perspective through the narratives of new entrants in organic farming outside the family farming succession. It aims to understand lived work experiences by considering both the daily constraints of the labour and the meanings and values invested in the work. The analysis focuses on the early years of organic farming operations. The research was carried out in Ardèche territory, a département in the Auvergne-Rhône-Alpes region, in southeastern France. We conducted a qualitative study based on semi-structured interviews with 15 new entrants who have established non-family farms and obtained organic certification. After transcription, the interviews were reviewed by using a triple-blind process. Edited transcripts were then uploaded to MaxQDA™ for inductive coding based on emerging themes and contextual analysis. Through the narratives of farmers regarding the constraints of work, we identified gendered effects in the responses concerning the available tools and equipment for agricultural work, the physical strain, strategies for prevention and self-care, balancing personal vs. professional life, and the social division of labor within couples. Unlike other studies, our analysis revealed no essentialist justifications for women's roles on farming. Moreover, our results show that the challenges of work are different for men and women. Men expressed concerns directly linked to working conditions, while women added work-life balance issues, notably linked to motherhood. A gendered perspective helped us to identify emerging work-related challenges faced by new entrants in organic farming, aiming to promote attractiveness and sustainable and inclusive working conditions for all
""Tout plaquer pour te lire". Pierre Seghers poète, éditeur, lecteur" https://www.youtube.com/watch?v=IxsxDOHGe2o
No full textInternational audienceThe lecture examines three business cards by Pierre Seghers to compare three ways of presenting oneself: to Jean Ballard, 1941; to Edmond Humeau [c. 1971]; and to André Frénaud, 1979. The first is actually a postcard that Seghers had made for his publishing house and depicts the village of Les Angles through an engraved woodcut by Jean Angladon, using this nighttime landscape to convey the editorial ethos of the small provincial artisan. The second, of extreme simplicity, devoid of any professional title or address, displays the name “Pierre Seghers” in spaced-out letters on a white background and corresponds to a decade in which Seghers was literally clearing the decks: he had left behind the responsibilities that consumed his time, even though he still felt hounded by parasitic tasks. The third, more elaborate, and featuring a reclaimed address, serves as the medium for a lament by the harried poet, who attempts to withdraw from the crucible of Parisian time, to leave everything behind to read. The story of an ordinary object that, in Pierre Seghers’ case, bears witness to an ability to reinvent himself by fleeing what he has built and which threatens to engulf him.La conférence confronte trois cartes de visite de Pierre Seghers pour comparer trois façons de se représenter : à Jean Ballard,1941 ; à Edmond Humeau [c. 1971] ; à André Frénaud, 1979. La première est en fait une carte postale que Seghers a fait faire pour sa maison d’édition et représente le village des Angles par un bois gravé de Jean Angladon, déployant par ce paysage nocturne l’éthos éditorial du petit artisan provincial. La deuxième, d’une sobriété extrême, dépourvue d’énoncé de la profession comme d’adresse, déploie en lettres espacées le nom de Pierre Seghers sur fond blanc et correspond à une décennie où Seghers fait littéralement le vide : il a quitté les responsabilités qui dévoraient son temps, même s’il se sent encore traqué par des travaux parasites. La troisième, plus ouvragée, et complétée d’une adresse reconquise, est le support d’une complainte du poète pressé, qui tente de s’abstraire de l’éprouvette du temps parisien, de tout plaquer pour lire. Histoire d’un objet ordinaire qui témoigne, dans le cas de Pierre Seghers, d’une capacité à se réinventer en fuyant ce qu’il a construit et qui menace de l’engloutir
Exploiting a school corpus of collaborative writing: methodological questions: Exploiting a school corpus of collaborative writing: methodological questions
No full textInternational audienceThis article analyzes the methodological choices made to exploit a subcorpus of collaborative school writings from a protocol of accompaniment to scriptural autonomy. Based on the successive versions produced by a group of students and the recording of their interactions, the aim is to understand the fragile dynamics of collaborative writing in a school context. The study articulates three types of data: the design of the writing device, its effective implementation in the classroom, and the complementary traces of the students' activity, in particular the pre-texts and oral interactions. The analysis is based on studies about oralographic situations, which makes it possible to observe the operations of textual elaboration "in progress". The article shows that interactions between students reveal negotiations, repetitions-modifications and adjustments that generate the putting into words, but also phenomena of regulation and conversation specific to the school context. These categories, specific to a captive audience and novice collaborative writing, require the adaptation of analytical tools from conversational adult writing. The study thus highlights the complex entanglement between preparation, formulation, comments and regulations, and proposes observables allowing a textometric analysis of such corpora.Cet article analyse les choix méthodologiques effectués pour exploiter un sous corpus d’écrits scolaires collaboratifs issus du protocole d’accompagnement à l’autonomie scripturale. À partir des versions successives produites par un groupe d’élèves et de l’enregistrement de leurs interactions, il s’agit de comprendre la dynamique fragile de l’écriture collaborative en contexte scolaire. L’étude articule trois types de données : la conception du dispositif d’écriture, sa mise en œuvre effective en classe, et les traces complémentaires de l’activité des élèves, notamment les avant textes et les échanges oraux. L’analyse s’appuie sur les travaux sur les situations oralographiques, qui permettent d’observer les opérations d’élaboration textuelle « en train de se faire ». L’article montre que les interactions entre élèves révèlent des négociations, des reprises-modifications et des ajustements qui génèrent la mise en mots, mais aussi des phénomènes de régulation et de conversation propres au contexte scolaire. Ces catégories, spécifiques à un public captif et à une écriture collaborative novice, nécessitent d’adapter les outils d’analyse issus des rédactions conversationnelles d’adultes. L’étude met ainsi en évidence l’intrication complexe entre préparation, formulation, commentaires et régulations, et propose des observables permettant une analyse textométrique de tels corpus
Cadichon, Black Beauty et Kholstomer : des individualités animales
No full textInternational audienceMémoires d’un âne by the Comtesse de Ségur (1860), Black Beauty by Anna Sewell (1877) and Kholstomer by Leo Tolstoy (1886) are three representative examples of fictional animal autobiographies from the second half of the 19th century. The closeness between humans and equines in contemporary society made these narratives ideal vehicles for allegorically denouncing the oppressed, such as workers in Victorian England, serfs in Tsarist Russia or, in children’s literature, children themselves. However, these fictional works also reflect, albeit only occasionally, a concern to represent animals for their own sake. The choice of autobiographical writing is certainly a convention, but it also facilitates an exploration of language and achieves the effect of defamiliarization, calling the boundary between humans and non-humans into question.Mémoires d’un âne de la Comtesse de Ségur (1860), Black Beauty d’Anna Sewell (1877) et Kholstomer de Léon Tolstoï (1886) sont trois récits représentatifs des autobiographies animales fictives de la seconde moitié du XIXe siècle. La proximité entre humains et équidés, dans la société contemporaine, fait de ces derniers des supports privilégiés pour dénoncer, de manière allégorique, les dominés que sont les travailleurs de l’Angleterre victorienne, les serfs de la Russie tsariste ou encore, dans les romans pour la jeunesse, les enfants eux-mêmes. Toutefois, les récits étudiés manifestent également, ne serait-ce que ponctuellement, le souci de représenter les animaux pour eux-mêmes. Le choix de l’écriture de type autobiographique est certes une convention,mais il permet également de déployer une interrogation sur le langage et de produire des effets de défamiliarisation qui mettent en question la frontière entre humains et non-humains.L'article est disponible sur Cairn : https://shs.cairn.info/revue-romantisme-2026-1-page-88?lang=f
Évaluer l’inclusivité d’un dispositif numérique dans l’éducation : enjeux et méthodologie (GTnum #EvalNumInclus)
No full textBulletin de veille réalisé dans le cadre du GTnum #EvalNumInclusDans le cadre du GTnum #EvalNumInclus, sont analysés les enjeux socioscolaires de l’évaluation de l’inclusivitéd’un dispositif numérique. En effet, le recours privilégié, dans le contexte actuel, aux aides techniques et artefacts numériques dans le champ du handicap ou des troubles des apprentissages, pourrait conduire à une approche restrictive de l’analyse de la plus-value inclusive des outils numériques. Il s’avère en conséquence essentiel d’examinerl’importance relative et la répartition des travaux scientifiques centrés, d’un côté, sur la logique interne des outils (l’intentionnalité de leur conception), souvent orientée vers la compensation d’un trouble ou d’une pathologie, et, de l’autre, sur leur usage dans un contexte pédagogique situé didactiquement par rapport à un ou plusieurs objectifs d’apprentissage clairement identifiés
Les Suds dans la gouvernance économique: Comment les Suds pèsent-ils dans des instances où ils ont une voix minoritaire ? Le cas des relations entre la CNUCED et le FMI (1961-1976)
No full textInternational audienceAprès les décolonisations, les pays des Suds se constituent en groupe politique pour transformer le système économique international via les Nations unies. La Conférence des Nations Unies sur le Commerce et le Développement (CNUCED) est créée en 1964 dans cette optique. Parallèlement, l’économie mondiale connaît un bouleversement majeur : l’affaiblissement puis la chute du système de Bretton Woods durant les années 1970. L’historiographie estimait jusqu’ici qu’un cercle restreint de pays occidentaux avait seul mené les négociations monétaires et financières de cette période. Cette thèse adopte une perspective opposée. Elle révèle la présence insoupçonnée de la CNUCED dans les débats monétaires et financiers multilatéraux, en coopération avec le FMI. À travers les échanges CNUCED-FMI, ces recherches mettent en lumière la participation des diplomates, banquiers centraux et économistes d’Amérique latine, d’Asie et d’Afrique à la gouvernance monétaire mondiale des années 1960-1970. Ces acteurs ont joué un rôle méconnu mais important, poussant le FMI à adapter ses politiques aux besoins des pays en développement, alors que le Fonds cherchait une nouvelle raison d’être. Malgré l’indépendance formelle et l’opposition intellectuelle entre FMI et ONU, le Fonds participa au tournant des Nations unies vers le développement
Structure from rank: Rank-order coding as a bridge from sequence to structure
No full textInternational audienceUnderstanding how structured sequence information can be represented and generalized in neural systems is key to modeling the transition from acoustic input to emergent structure. In this study, we propose a rank-order based neural network inspired by the STG-LIFG-PMC pathway, modeling the bottom-up transition from acoustic input to abstract rank representation and the top-down generation from that representation to motor execution. Building on previous work in rank coding, we first demonstrate that this model efficiently compresses input while retaining the capacity to reconstruct full utterances from partial cues, revealing emergent structure-sensitive generation process that reflects context-general representations of sensorimotor states, which are later shaped into context-specific motor plans during speech planning. We then show that the network exhibits global-level novelty detection similar to the P3B novelty wave, replicating the global-sequence-sensitive mechanism. As a supplement, we also compare the model’s behavior under local (index-level) and global (rank-level) perturbations, revealing robustness to superficial variation and sensitivity to abstract structural violation, key features associated with hierarchical generalization. These results suggest that rank-order coding not only serves as a compact encoding scheme but also captures hierarchical structure in acoustic sequences
Is non-local communication really impossible?
No full textThis paper shows the possibility of non-local communication between two entangled, spacelike separated sub-systems. More specifically, it is shown that if there exist (at least) two non-commuting observables respectively defined on these two sub-systems then, for some entangled state of the global system, the probability distribution of the outcomes of measurements performed in one of its parts is changed by the actions that have been performed in the other one. This causal dependency, which includes that of the settings, makes possible a nonlocal exchange of information between the parties
Evidence for seawater Mg/Ca and dietary control on Mg incorporation in oyster shells
No full textInternational audienceThe Mg/Ca ratio in bivalve shells has been investigated as a promising proxy for temperature reconstruction of the seawater. However, important discrepancies exist among the Mg/Ca-temperature calibrations reported for bivalves in the literature. These discrepancies currently limit the use of Mg/Ca for paleoclimate reconstructions based on bivalves and suggest that factors beyond temperature influence Mg incorporation in the shell. In particular, several studies have highlighted empirical differences in the seasonal amplitudes of shell Mg/Ca between two types of environments: river-influenced coastal settings and open marine systems. In this study, we investigate several environmental parameters that may account for these differences, using rearing experiments of oysters in both natural and artificial seawater. First, we tested the influence of Mg speciation in seawater on shell Mg/Ca and showed that Mg is incorporated in the shell regardless of its form (free or complexed with organics). Second, we investigated the sensitivity of shell Mg/Ca to seawater Mg/Ca by artificially increasing the Mg concentration in seawater. We observed an increase in shell Mg/Ca concomitant with the rise in seawater Mg/Ca, confirming the dependance of shell Mg/Ca on seawater Mg content. Finally, we show that a change in diet induces a significant difference in shell Mg/Ca, and that shell Mg/Ca is positively correlated with the Mg/Ca of the diet. Overall, our results suggest that, in addition to temperature, both seawater and dietary Mg/Ca ratios control shell Mg/Ca. These parameters could be responsible for the discrepancy between Mg/Ca-temperature models published in the literature, and should be carefully considered in future aquarium-based and in situ calibration studies, as well as paleoenvironmental reconstructions