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Des discours contradictoires. Le conflit des modèles éducatifs de la parole aux Ve-IVe siècles a.C
No full textInternational audienceThis presentation is concerned as much with the history of representations, linked to oral pedagogical practices, as with the history of mentalities, through the conception of a conflict that is both conceived and theorized. The guiding questions of this presentation are thus as follows: What forms does the pedagogical agonistic dimension take? How does educational conflict allow us to apprehend the transformations of pedagogical conceptions in the fifth and fourth centuries BCE?It therefore appears relevant, for the purposes of this presentation, to adopt a methodology grounded in the examination of the form of the agonistic process at work in the philosophical, sophistic, and comic texts under study: first, through the emphasis placed on the confrontation of two contradictory discourses, and second, through the embodied opposition of conflict as manifested in divisive educational practices.The conflict linked to educational models of speech involves the recognition of an Other. Accordingly, to focus on the elaboration of discourses on conflict entails interrogating ancient cultural productions: the terms agôn and paideia are once again intertwined through the lens of competition and, in this case, of education.Cette communication s’intéresse tout autant à l’histoire des représentations, liée aux pratiques pédagogiques orales, qu’à l’histoire des mentalités avec la conception d’un conflit pensé et théorisé. Les axes de questionnement de la communication sont ainsi les suivants : Quelles formes la dimension agonistique pédagogique prend-elle ? Comment le conflit éducatif permet-il d’appréhender les mutations des conceptions pédagogiques des Ve-IVe siècles ?Il apparait ainsi pertinent pour cette communication de suivre une méthodologie fondée sur l’interrogation de la forme du procédé agonistique à l’œuvre dans les textes philosophiques, sophistiques et comiques à l’étude : dans un premier temps par la mise en valeur qui est faite de deux discours contradictoires puis, dans un second temps, par l’opposition incarnée du conflit à travers des pratiques éducatives clivantes.Le conflit lié aux modèles éducatifs de la parole passe par la reconnaissance d’un Autre. Or, s’intéresser à l’élaboration des discours sur le conflit implique de questionner les productions culturelles antiques : les termes agôn et paideia se trouvent de nouveau liés au prisme du concours et, ici, de l’éducation
Combining mitochondrial morphology and cellular metabolism measurements improves colorectal cancer cell classification
No full textInternational audienceBackground: In many diseases, including cancer, the number, distribution and shape of mitochondria are affected. Under stress conditions and in tumor cells, changes in cellular, nuclear and mitochondrial morphology are frequently observed. Mitochondria are responsible for energy production and metabolic reprogramming is recognized as a hallmark of cancer, including colorectal cancer (CRC), the third most common and second most deadly cancer worldwide. CRC is a heterogeneous disease, with each subtype exhibiting distinct molecular features that lead to diverse clinical outcomes. The relationship between mitochondrial morphology, metabolic status, and CRC progression has not yet been formally investigated. Here, we sought to determine whether quantitative imaging of mitochondrial shapes, in addition to metabolic measurements, could provide useful information for CRC subtyping. Methods: We recently developed a novel wet-and-dry imaging pipeline (MITOMATICS) that enables the quantitative measurement of a wide range of mitochondrial shapes in their native cellular environment using highcontent confocal microscopy screening. This automated pipeline, which includes statistical tests as well as supervised and unsupervised machine learning tools for analysis and visualization, was applied to monitor mitochondrial morphology in a cellular model of colon cancer progression consisting of various CRC cell lines along with paired non-tumoral cell lines. The metabolic phenotype of the multiple cell subsets was also determined in order to draw inter-assay comparisons. Results: We observed that mitochondria in CRC cells were swollen and formed a fragmented network, whereas in their non-tumor counterparts, mitochondria were found to be elongated and organized into a complex branched network. Statistical analysis confirmed a clear separation between normal and CRC cells, as well as among the various CRC subtypes, based on mitochondrial morphology. In addition, our results showed that both glycolysis and OXPHOS increased as a function of CRC progression, with each tumor cell line displaying a specific metabolic signature. Interestingly, combining both types of mito-signatures improved classification accuracy. Conclusion: Integration of mitochondrial shape phenotyping and metabolic profiling improves CRC cancer cell classification and could provide a novel type of biomarker for CRC screening and therapeutic decision-making
Self-Portrait of the Focusing Process in Speckle: I. Spatio-Temporal Imaging of Wave Packets in Complex Media
No full textInternational audienceThis is the first article in a series of three dealing with the exploitation of speckle for imaging purposes. Speckle is the complex interference wave-field produced by a random distribution of un-resolved scatterers. In this paper, we show how these scatterers can be used as virtual microphones to monitor the spatio-temporal propagation of a wave-packet inside the medium. To do so, the concept of matrix imaging is particularly useful. It consists in decoupling the location of the transmitted and received focal spots in a standard beamforming process. By scanning the wave-field with the output focal spot that then acts as a virtual transducer, one can image the spatio-temporal evolution of the wave-packet inside the medium. This unique observable will allow us to highlight the imperfections of the focusing process, in particular the defocus and reverberations induced by a strong aberrating layer. As a proof-of-concept, we will consider ultrasound experiments on tissue-mimicking phantoms. In the next two papers, we will show how this observable can be leveraged to compensate for these phenomena that hamper wave focusing and imaging in all fields of wave physics. Our method is indeed broadly applicable to different types of waves beyond ultrasound for which multi-element technology allows a reflection matrix to be measured.A speckle pattern is the result of a random interference between many waves
Mapping the political landscape from data traces: multidimensional opinions of users, politicians and media outlets on X
No full textStudying political activity on social media often requires defining and measuring political stances of users or content. Relevant examples include the study of opinion polarization, or the study of political diversity in online content diets. While many research designs rely on operationalizations best suited for the US setting, few allow addressing more general political systems, in which users and media outlets might exhibit stances on multiple ideology and issue dimensions, going beyond traditional Liberal-Conservative or Left-Right scales. To advance the study of more general online ecosystems, we present a dataset pertaining to a population of X/Twitter users, parliamentarians, and media outlets embedded in a political space spanned by dimensions measuring attitudes towards immigration, the EU, liberal values, elites and institutions, nationalism and the environment, in addition to left-right and liberal-conservative scales. We include indicators of individual activity and popularity: mean number of posts per day, number of followers, and number of followees. We provide several benchmarks validating the positions of these entities and discuss several applications for this dataset
Constraints on gravitational waves from the 2024 Vela pulsar glitch
No full textInternational audienceAmong known neutron stars, the Vela pulsar is one of the best targets for gravitational-wave searches. It is also one of the most prolific in terms of glitches, sudden frequency changes in a pulsar's rotation. Such glitches could cause a variety of transient gravitational-wave signals. Here we search for signals associated with a Vela glitch on 29 April 2024 in data of the two LIGO detectors from the fourth LIGO--Virgo--KAGRA observing run. We search both for seconds-scale burst-like emission, primarily from fundamental (f-)mode oscillations, and for longer quasi-monochromatic transients up to four months in duration, primarily from quasi-static quadrupolar deformations. We find no significant detection candidates, but for the first time we set direct observational upper limits on gravitational strain amplitude that are stricter than what can be indirectly inferred from the overall glitch energy scale. We discuss the short- and long-duration observational constraints in the context of specific emission models. These results demonstrate the potential of gravitational-wave probes of glitching pulsars as detector sensitivity continues to improve
Multi-wavelength Study of A Superflare on RS CVn-type Star HD22468 Triggered at Hard X-ray by SVOM
No full textInternational audienceDetection of stellar flares at hard X-ray is still rare at the current stage. A transient was recently detected by the hard X-ray camera, ECLAIRs onboard the SVOM mission at 11:39:01.2UT on 2025, January 09. Simultaneous monitor in the optical band on the ground by SVOM/GWAC and follow-up spectroscopy enable us to confirm that the transient is caused by a superflare on HD~22468, a RS CVn-type star. The bolometric energy released in the flare is estimated to be . The hard X-ray spectra of the event at the peak can be reproduced by the ``apec'' model of a hot plasma with a temperature of ~MK. In the optical range, the H emission-line profile obtained at hrs after the trigger shows a bulk blueshift of , which can be explained by either a chromospheric evaporation or a prominence eruption. The ejected mass is estimated to be g for the evaporating plasma, and to be for the erupted prominence
Travailler avec le son en anthropologie : Un entretien avec Christine Guillebaud
No full textInternational audienceChristine Guillebaud, ethnomusicologue travaillant sur l'Asie du Sud, explicite dans cet entretien réalisé par Tristan Bruslé et Anne Castaing comment son parcours anthropologique fut nuancé et enrichi par son travail sur le son : que peut apporter le son à l'anthropologie, et quelle est sa place dans la discipline ? Comment l'enseigner ? Comment transmettre et conserver les travaux menés sur le son en anthropologie ? Cet entretien est la restitution, retravaillée en concertation avec Christine Guillebaud, d'une table-ronde sur les écritures alternatives tenue lors des Assises de la Recherche sur l'Asie le 18 septembre 2024
Uncovering genetic population structure in the Endangered northern rockhopper penguin (Eudyptes moseleyi) across islands in the Southern Atlantic and Indian oceans
No full textInternational audienceBackground: The northern rockhopper penguin (Eudyptes moseleyi) is a threatened species, listed as Endangered globally by the IUCN owing to rapid population decreases in the past, combined with a limited distributional range. Their breeding is confined to five islands in the central South Atlantic Ocean (Gough, Nightingale, Inaccessible, Alex (= Middle), and Tristan da Cunha) and two islands in the southern Indian Ocean (Amsterdam and Saint Paul). Nonbreeding birds forage widely in these oceans and vagrant individuals have been recorded in the Falkland Islands/ Malvinas, South Africa, Kerguelen Archipelago, Australia, and New Zealand. The origins of these vagrant birds are largely unknown, and it remains unclear to what extent northern rockhopper penguins move between islands and oceans. Understanding connectivity between populations is essential for developing appropriate conservation strategies, especially as some populations may be at greater extinction risk than others.Results: Northern rockhopper penguins from the two oceanic basins are genetically distinct, with minimal evidence of migration between ocean basins. No substructure was detected within ocean island groups and although low, the level of migration between islands was sufficient to prevent genetic differentiation. Differential signatures of genetic diversity and inbreeding may also suggest some island populations are at higher risk of inbreeding depression. Conclusions: This study provides the first comprehensive genetic population structure analysis of the entire breeding range of the Endangered northern rockhopper penguin. This gives an unparalleled understanding of the connectivity within and between populations breeding in the Atlantic and Indian oceans, and highlights areas for further investigation. Knowledge of genetic structure and population dynamics can inform effective conservation management by predicting a species’ ability to adapt and remain resilient to local or global threats, including the increasing impacts of climate-driven changes in marine environments. Our results suggest that northern rockhopper penguins should be managed as two conservation management units to maximise the conservation of genetic diversity within the species and allow strategies to be developed that consider the different pressures affecting the populations in each ocean basin
Évaluation de l’impact du projet PILAEP 2 dans les quartiers périphériques de Kinshasa (RDC)
No full textIn the Democratic Republic of Congo (DRC), only a third of the population has basic access to drinking water. The lack of access to drinking water is particularly marked in urban areas, especially in the capital city of Kinshasa and its outlying districts. This results in poor hygiene and sanitation conditions and in large amounts of time spent every day for collecting water. To improve this situation, AFD initiated the PILAEP "Promotion de modalités Innovantes pour L'Accès à I'Eau Potable" (2008-2012) and PILAEP2 (2017-2021) projects, which involve setting up autonomous drinking water distribution networks for people living in the outlying districts of Kinshasa and Bas Congo who are not served by the national water distribution company (REGIDESO). Each network is managed by a Users' Association (ASUREP) and comprises a borehole, a reservoir, a distribution network and a system of standpipes, capable of supplying 1,000 inhabitants with drinking water. This report presents the impact assessment of the PILAEP2 project. The first section describes the evaluation protocol and the survey methods used to measure the project's impact. The second section presents descriptive analyses of the study districts, their demographic dynamics and changes in water supply and demand over the study period. The third section presents the results of the evaluation of the impact of the PILAEP 2 project on the populations targeted by the project, focusing on five groups of indicators: water supply, physical and mental health, education, employment and governance.En République Démocratique du Congo (RDC), seul un tiers de la population bénéficie d'un accès basique à l'eau potable. Le manque d’accès à l’eau potable est particulièrement criant en ville, et notamment dans la capitale Kinshasa et ses quartiers périphériques, ce qui se traduit par des conditions d'hygiène et d'assainissement fortement dégradées, auxquelles s'ajoute le poids de la corvée d'eau. Afin d’améliorer cette situation, l’AFD a été à l’initiative des projets PILAEP « Promotion de modalités Innovantes pour L'Accès à I’Eau Potable » (2008-2012) et PILAEP2 (2017-2021) consistant en la mise en place de réseaux autonomes de distribution d’eau potable à destination des populations des quartiers périurbains de Kinshasa et du Bas Congo non desservis par la régie nationale de distribution d’eau (REGIDESO). Chaque réseau est géré par une Association d’Usagers (ASUREP) et se compose d’un forage, d’un réservoir, d’un réseau de distribution et d'un dispositif de bornes-fontaines, susceptibles de pouvoir alimenter en eau potable (payante) 1000 habitants. Le présent rapport restitue le travail d’évaluation de l’impact du projet PILAEP2. La première section décrit le protocole d’évaluation et les dispositifs d’enquête mis en œuvre pour mesurer l’impact du projet. La deuxième section présente des analyses descriptives sur les quartiers de la zone d’étude, leurs dynamiques démographiques et l’évolution de l’offre et de la demande en eau au cours de la période d’étude. La troisième section présente les résultats de l’évaluation de l’impact du projet PILAEP 2 sur les populations ciblées par le projet, en se concentrant sur cinq groupes d’indicateurs : l’approvisionnement en eau, la santé physique et mentale, l’éducation, l’emploi et la gouvernance
Phylogeny, systematics and evolution of mimicry patterns in Neotropical limenitidine butterflies
No full textDATA AVAILABILITY STATEMENT: The data that support the findings of this study are openly available in the Dryad repository at https://doi.org/10.5061/dryad.7h44j104b (Pàez et al, 2025). Newly generated sequences were deposited in GenBank at https://www.ncbi.nlm.nih.gov and are registered with the following accession numbers: PX243222–PX243274, PX244453–PX244551 (COI); PX114826–PX114854 (EF1a); PX172283–PX172334 (GAPDH); PX172335, PX254824–PX254850 (IDH); PX254786–PX254823 (RpS5); PX207538–PX207552 (ArgKin); PX172259–PX172282 (CAD); PX207522–PX207537 (CycY); PX172235–PX172258 (DDC); PX270910–PX270945 (Exp1); PX172202–PX172234 (Nex9); PX114965–PX115012 (PolII); PX114932–PX114964 (ProSup); PX114890–PX114931 (PSb); PX114855–PX114889 (RpS2); PX207556–PX207592 (UDPG6DH) (see Table S1 for details).International audienceThe Neotropical butterfly genus Adelpha Hübner exhibits remarkable species diversity and striking convergence in wing colour patterns potentially explained by mimicry, making it an exceptional model for exploring trait evolution and its relationship with speciation. To date, unresolved phylogenetic relationships hinder a comprehensive understanding of the evolutionary biology of the genus. Using a novel multi‐marker dataset combining one mitochondrial and 15 nuclear gene fragments, we generate the most comprehensive phylogeny of the genus Adelpha to revisit its systematics and investigate the evolution of mimicry colour patterns. Our dataset encompasses 83 of the 87 known extant species and six Limenitis species that were recently excluded from Adelpha (134 of c . 160 subspecies in total), collectively displaying 14 distinct mimicry patterns. We provide conclusive evidence that corroborates previous work on the polyphyly of Adelpha as historically conceived and describe the genus Adelphina Páez & Willmott n. gen . to stabilise the nomenclature. The comprehensive phylogeny provided in this study lays a solid foundation for future research into the processes driving diversification within these species interacting through mimicry. Ancestral character state reconstruction reveals the gradual evolution of mimicry patterns. The more common mimicry pattern IPHICLUS (forewing with orange subapical spot and white band) is inferred as ancestral, but repeated convergent evolution is also recovered. Evolutionary convergence is also observed for the second most abundant mimicry pattern, COCALA (orange‐white banded). Increased rates of mimicry pattern evolution are also found towards the equator. These results underscore the complexity of mimicry evolution in the Neotropical limenitidines, i.e., Adelpha and Adelphina n. gen. , emphasising the need to explore its interplay with other biotic and abiotic factors