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Vaccination against H5 HP avian influenza virus leads to persistent immune response in wild king penguins
No full textInternational audienceSince 2021, the panzootic nature of high pathogenicity avian influenza (HPAI) represents an increasing threat to wild vertebrate populations. In this context, recent vaccines developed for poultry could provide tools for the conservation of wild endangered birds populations. The king penguin ( Aptenodytes patagonicus ), a long-lived seabird breeding in dense colonies with an extended chick-rearing period, has been identified as a possible surrogate species for a vaccination trial in a sub-Antarctic natural setting. Here we investigate the immune response of king penguin chicks to a self-amplifying mRNA vaccine against a H5 HPAI clade 2.3.4.4b protein. The cohort entails thirty vaccinated chicks (primo- and boost-injections), and 20 unvaccinated controls. Along 250 days of monitoring, the vaccinated chicks show a high and persistent immune response, granting a strong sero-neutralisation capacity against the virus, up to fledging. No adverse effects are observed. Screening for antibodies against unspecific avian influenza viruses suggests that no natural infection has occurred over the entire trial. The emergence of HPAI in the Southern Indian Ocean in October 2024 highlights the timeliness of such experimental tests. Our results thus show the vaccine could provide a potentially powerful tool for mitigation of avian flu outbreaks in the wild
Mitigating structural deterioration via partial substitution with Fe in Mn-based Prussian white cathodes for Na-ion batteries
No full textInternational audiencePrussian white (PW) is a promising cathode material for sodium-ion batteries (SIBs), which offers high theoretical capacity at low cost while being composed of abundant elements. However, Fe-based PW suffers from relatively low average voltage, and while substitution of one Fe with Mn can increase the voltage, it introduces structural instabilities supposedly due to the Jahn–Teller distortion of Mn3+, resulting in poor capacity retention. In this work, we investigate the effect of partial substitution of Mn by Fe in Mn-based PW on electrochemical and structural stability. Two samples, Na1.82Mn[Fe(CN)6]0.96·2.0H2O and Na1.82Mn0.62Fe0.38[Fe(CN)6]0.96·2.1H2O, were synthesized by coprecipitation and characterized via a multimodal approach combining laboratory and synchrotron-based techniques. We demonstrate that partial Mn substitution by Fe does not eliminate Jahn–Teller distortion but mitigates its negative effects by suppressing the distorted phase formation occurring near end of charge, thereby significantly enhancing capacity retention without sacrificing overall capacity. These results provide fundamental insight into the interplay between redox activity and structural stability in mixed-metal PW and establish partial Mn substitution by Fe as an effective strategy to improve long-term cyclability of PW cathodes for SIBs
La pédagogie comme petite source des droits et libertés ? L’éducation aux droits humains comme rempart face aux transformations de l’autorité du DIDH
No full textInternational audienceDrawing on doctoral research devoted to the right to human rights education, this article examines the role of pedagogy in the contemporary making of international human rights law (IHRL). While pedagogy is not recognized as a formal source of international law, it nonetheless operates as a fully-fledged material source, contributing to the dissemination of a human rights culture. By analysing manuals, guidelines and pedagogical tools produced by the Office of the High Commissioner for Human Rights, the article demonstrates that these instruments do not merely transmit existing law, but actively shape it by structuring legitimate forms of knowledge and producing diffuse forms of normativity. This evolution reveals a shift in the authority of IHRL, characterised by processes of de-juridification and ethicalisation of international normativity, giving rise to tensions between emancipatory ambitions and implicit processes of normalisation.À partir d’une recherche doctorale consacrée au droit à l’éducation aux droits humains, cet article analyse le rôle de la pédagogie dans la fabrique contemporaine du droit international des droits de l’Homme (DIDH). S’il est admis que la pédagogie ne constitue pas une source formelle du droit international, elle apparaît néanmoins comme une source matérielle à part entière, participant à la diffusion d’une culture des droits humains. En examinant les manuels, guides et outils pédagogiques produits par le Haut-Commissariat aux droits de l’homme, l’article montre que ces dispositifs ne se limitent pas à transmettre le droit existant, mais contribuent à le modéliser, à orienter les savoirs légitimes et à produire une normativité diffuse. Cette évolution révèle un déplacement de l’autorité du DIDH, marqué par une déjuridictionnalisation et une éthicisation de la normativité internationale, soulevant des tensions entre visée émancipatrice et processus de normalisation implicite
When inflationary perturbations refuse to classicalise: the role of non-Gaussianity in Wigner negativity
No full textInternational audienceInflationary perturbations are quantum in origin. Yet, when computing cosmological observables, they are often treated as classical stochastic fields. Do they nevertheless retain quantum birthmarks? A hallmark of genuinely quantum behaviour is quantum interferences, arising from phase coherence between distinct branches of the wavefunction. Such interference is diagnosed by the non-positivity of the Wigner function, and according to Hudson's theorem, the only pure states with positive Wigner functions are Gaussian states. Consequently, any departure from Gaussianity necessarily implies a non-positive Wigner function, precluding a description in terms of a classical distribution. This motivates us to compute the Wigner function of curvature perturbations, accounting for primordial non-Gaussianities, using the EFT of inflation. We find that the Wigner function develops pronounced interference fringes on super-Hubble scales, and in particular, its negativity grows as in ultra-slow-roll backgrounds. These results demonstrate that quantum effects can remain significant at late times, and that squeezing alone does not ensure classicality, contrary to standard lore. This suggests that the prospects for detecting genuinely quantum signatures of the universe's origins in cosmological observables may be less bleak than previously thought
Le pouvoir discrétionnaire de l'administration à l'épreuve de l'intégration des IA
No full textRepenser le management à l'ère de l'IA.Face à l’avènement de l’intelligence artificielle générative, le monde du management est à un tournant. Doit-il être repensé ?Comment cette technologie redéfinit-elle les règles du jeu ?Quels sont les enjeux pour l’enseignement, l’entreprise et les services publics ?Cet ouvrage novateur propose une analyse multidimensionnelle et approfondie de l’impact de l’IA générative sur le management.Trois angles sont abordés :• L’enseignement du management : la transformation des compétences managériales, les modes d’apprentissage et les rôles futurs des formateurs et des étudiants.• Les performances des organisations : l’influence de l’IA sur la stratégie d’entreprise, le marketing, la logistique, l’entrepreneuriat, les gains d’efficacité et d’innovation.• Le management public : les défis éthiques, organisationnels et de responsabilité que l’IA soulève pour les institutions de l’État.Fruit des travaux de recherche d’enseignants-chercheurs du Laboratoire de recherche en sciences de gestion de l’Université Paris Panthéon-Assas (LARGEPA), ce livre offre une perspective éclairée pour tous les professionnels, chercheurs et étudiants désireux de comprendre les implications profondes de l’IA générative sur le management d’aujourd’hui et de demain
Scattering angle at 3PM in scalar-tensor theories using the PM-EFT formalism
No full textInternational audienceIn this work, we derive the conservative dynamics of non-spinning binaries in the massless scalar-tensor theories using the post-Minkowskian Effective Field Theory (EFT) approach. Our main result is an analytic expression of the scattering angle, computed up to third Post-Minkowskian order via two-loop Feynman diagrams. Our results are in perfect agreement with previous literature, in particular within the post-Newtonian limit
2025, une année d’audace et de reconnaissance multiple pour la revue de l’organisation responsable
No full textInternational audienceAlzheimer's disease (AD) is a neurodegenerative disorder for which no effective preventative or curative treatment has yet been identified. Due to the multifactorial nature and complex pathophysiology of the disease, we developed a multi-target ligand that both inhibits human butyrylcholinesterase (hBChE), a key enzyme linked to β-amyloid plaque formation, andactivates the sigma-1 receptor (S1R), which modulates neuroinflammatory and protective pathways. To this end, a series of isoindolines were designed and synthesized, and their biological activity was evaluated. The most promising compound, 7c, exhibited significant dual activity, achieving nanomolar IC50 values against hBChE and potent S1R activation. Subsequent in vivo studies in an Aβ25-35 mouse model revealed an improvement in cognitive deficits in both short- and long-term memory at an effective dose of 0.01 mg/kg in WT Swiss-OF1 mice. This dose is 10-fold lower compared to single-target compounds 7a and 7b of this isoindoline series. The lack of neuroprotective effects in BChE knock-out (KO) mice confirmed the involvement of BChE inhibition for compounds 7c effects in WT mice. Further combinatorial studies employing a two-drug combination demonstrated synergy in the neuroprotective effect of the two targets
Lightcurves, Rotation Periods, and Colors for Vera C. Rubin Observatory’s First Asteroid Discoveries
No full textInternational audienceWe present lightcurves, rotation periods, and colors for the first asteroid discoveries made with the NSF-DOE Vera C. Rubin Observatory. These are the first science results derived from the 2103 asteroid discoveries released as part of the Rubin First Look (RFL) media event on 2025 June 23, in which the first LSST Camera commissioning images were released. The ∼340,000 observations in which the discoveries were made span nine nights between 2025 April 21 and May 5. With a limiting single-epoch 5σ depth of ∼23–25 mag and dense temporal sampling under an irregular, commissioning-driven cadence, the RFL observations provide an ideal test bed for determination of rotation periods, including sensitivity to rapid rotation. We model lightcurves and derive rotation periods and colors for the ∼2000 objects. We find 75 main-belt asteroids (MBAs) and one near-Earth object (NEO) with reliable rotation periods spanning 0.031–21.3 hr and a photometric precision in the range of 0.05–0.15 mag. We find 19 superfast rotators with periods shorter than the 2.2 hr spin barrier. Rubin-discovered MBA 2025 MN is the fastest-rotating d > 0.5 km known asteroid with a rotation period of 1.9 minutes; along with NEO 2025 MJ (1.9 minutes) and Rubin-discovered MBAs 2025 MK (3.8 minutes), 2025 MV (13 minutes), and 2025 MG (16 minutes), these five super- to ultrafast rotators join a couple of NEOs as the fastest-spinning subkilometer asteroids known. As this study demonstrates, even in early commissioning, Rubin is successfully probing a previously sparsely sampled region of the subkilometer size−spin rate regime for MBAs
Fallow land simulations to fight against soil degradation: Engaging stakeholders with model exploration
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/616636/) * Autres projets (id;sigle;titre): AF 1802-001;DSCATT;(FRA) Dynamics of Soil Carbon Sequestration in Tropical and Temperate Agricultural systems//International audienceThis methodological paper forms part of a modelling approach conducted in the Senegalese groundnut basin. It addresses two key aspects: (1) the process of co-constructing the model with local stakeholders; and (2) the use of calibration to account for non-measurable elements, which stakeholders needed to describe and evaluate their system effectively. Thematically, the study examines the relationship between social solidarity and agro-pastoral systems in Diohine, a Senegalese village where communal fallow lands are a vital indicator of socio-ecological resilience. Using the co-constructed, agent-based "Me re Diam" model, we examine the dynamics of soil fertility, population growth and agricultural yields over a 25-year period, integrating local knowledge and ecological data. Our findings emphasise the pivotal role of social solidarity mechanisms, such as parcel lending and food sharing, in stabilising agro-pastoral systems amidst resource scarcity. Calibrating the model demonstrates its ability to reproduce historical dynamics and test alternative practices. Without these mechanisms, the system collapses, revealing their indispensable nature for long-term sustainability. This work emphasises the importance of collaborative modelling in bridging the gap between empirical data and local practices, providing actionable insights for addressing soil degradation and demographic pressures