Philippe JEAN-PIERRE

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• Type de publi. : Pré-publication, Document de travail
• Date de publi. : 27/08/2023
• Auteurs : Christian PichotPhilippe ClastreAmélie FioccaMariya Evtimova-GardairBenjamin JailletAytac OzcanFabrice BénédetAlain BouvetPriscilla CaillyFrançois CourbetChristine DeleuzeChristian GinistyBruno HéraultDamien MauriceCéline MeredieuCélia MichoteyWulfran MirlyazChristophe OrazioEric PaillassaCéline PerrierPlinio SistTiffani PozziJean-Pierre RenaudLaurent Saint‐andréS Said
• Organismes : Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement Département écologie et biodiversité des milieux forestiers, prairiaux et aquatiques Ecologie des Forêts Méditerranéennes Ecosystèmes forestiers Biodiversité, Gènes & Communautés Unité Mixte de Recherche d'Épidémiologie des maladies Animales et zoonotiques

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Résumé : Ensemble des documents élaborés dans le cadre du développement du Système d'Information (SI) IN-SYLVA France. Cette publication comporte plusieurs document élaboré au cours du projet. (i) in-sylva_cahier_des_charges: cahier des charges pour le développement du SI (format pdf). (ii) in-sylva_standard:description des champs utilisé pour le standard de métadonnées IN-SYLVA (format pdf). (iii) in-sylva_referentiel_interne: référentiel des termes mobilisés par la communauté IN-SYLVA (format SKOS/RDF). (iv)in-sylva_referentiel_externe: référentiel des termes mobilisés au sein du projet IN-SYLVA mais provenant de sources extérieures (format SKOS/RDF).

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• Type de publi. : Article dans une revue
• Date de publi. : 21/08/2023
• Auteurs : Boris DmitrenkoVincent GatinoisMorgana D’ottaviAhmed El MouataniPauline BouretSégolène DebiesseMichel MondainMohamed AkkariMaxime DallemagneFranck PellestorPhilippe Van de PerreJean-Pierre Moles
• Organismes : Pathogenesis and Control of Chronic and Emerging Infections Pathogenesis and Control of Chronic and Emerging Infections Pathogenesis and Control of Chronic and Emerging Infections Pathogenesis and Control of Chronic and Emerging Infections Pathogenesis and Control of Chronic and Emerging Infections
• Publié dans Cells le 01/11/2020

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Résumé : The factors influencing mother-to-child cell trafficking and persistence over children's lives have yet to be established. The quantification of maternal microchimerism was previously reported through HLA-based approaches, which introduced bias regarding the tolerogenic environment. We aimed to identify cells of maternal origin irrespective of the HLA repertoire and to ascertain the determinants of microchimeric cells. This case-control study enrolled 40 male infants attending pediatric surgery from January 2022 to October 2022. Female cells were quantified in infants' tonsil tissue by using cytogenetic fluorescent in situ hybridization (FISH) coupled with optimized automated microscopy. Out of the 40 infants, half (47.4%) had been breastfed for more than one month, a quarter for less a month, and 10 children (26.3%) were never breastfed. XX cells were observed in male tonsils in two-thirds of participants at a median density of 5 cells per 100,000 cells. In univariate analyses, child age was negatively associated with a high female cell density. In exploratory multivariate analyses, previous breastfeeding is a likely determinant of the persistence of these cells in the host, as well as the rank among siblings. Part of the benefit of breastmilk for child health may therefore be driven by breastfeeding-related microchimerism.

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Fichiers liés : cells-12-02116.pdf

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• Type de publi. : Communication dans un congrès
• Date de publi. : 20/08/2023
• Auteurs : Thierry AllarioAlice FourquezMaryline Magnin-RobertAli SiahAlessandra Maia-GrondardMatthieu GaucherMarie-Noëlle BrissetPhilippe HugueneyPhilippe ReignaultRaymonde BaltenweckBéatrice Randoux
• Organismes : Unité de Chimie Environnementale et Interactions sur le Vivant Unité de Chimie Environnementale et Interactions sur le Vivant Unité de Chimie Environnementale et Interactions sur le Vivant BioEcoAgro - UMR transfrontalière INRAE 1158 Institut Jean-Pierre Bourgin - Sciences du végétal Institut de Recherche en Horticulture et Semences Unité de recherche Pathologie végétale et phytobactériologie Santé de la vigne et qualité du vin Unité de Chimie Environnementale et Interactions sur le Vivant Université de Strasbourg Santé de la vigne et qualité du vin Unité de Chimie Environnementale et Interactions sur le Vivant

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Résumé : Blumeria graminis f.sp. tritici (Bgt) is an obligate biotrophic fungal pathogen responsible for powdery mildew in bread wheat (Triticum aestivum L.). During the firststeps of this pathogenic interaction, basal defense mechanisms take place in wheat leaves. We used RT-qPCR and metabolomic approaches to analyze these earlystages of the interaction between Bgt and the moderately susceptible wheat cultivar Pakito. The expression of genes encoding pathogenesis-related (PR) proteins (PR1,PR4, PR5 and PR8), known to target the pathogen, increased during the first 48 hours post-inoculation. Moreover, RT-qPCR and metabolomic analyses pointed out theimportance of the phenylpropanoid pathway in quantitative resistance against Bgt. Among metabolites of this pathway, hydroxycinnamic acid amides containing agmatineand putrescine as amine components accumulated from the second to the fourth day after inoculation. This suggests the involvement of these metabolites in quantitativeresistance via cross-linking processes in cell wall for reinforcement, what is supported by the up-regulation of PAL (phenylalanine ammonia-lyase), PR15 (encoding anoxalate oxidase) and POX (peroxidase) further inoculation. This study increases knowledge on basal resistance in wheat, giving new targets to investigate inducedresistance in wheat towards Bgt.

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• Type de publi. : Communication dans un congrès
• Date de publi. : 20/08/2023
• Auteurs : Matthieu FritzBérénice ReggiardoDenis FillouxLisa ClaudeEmmanuel FernandezFrédéric MahéSimona KrabergerJoy M. CusterPierre BecquartTelstar Ndong MebaleyLinda Bohou KombilaLéadisaelle Hosanna LenguiyaLarson BoundengaIllich Manfred MomboGael D. MagandaFabien Roch NiamaJean-Sylvain KoumbaMylène OgliastroMichel YvonDarren Patrick MartinStéphane BlancArvind VarsaniEric M. LeroyPhilippe Roumagnac
• Organismes : Institut de Recherche pour le Développement Plant Health Institute of Montpellier Plant Health Institute of Montpellier Plant Health Institute of Montpellier Arizona State University [Tempe] Arizona State University [Tempe] Institut de Recherche pour le Développement Centre Interdisciplinaire de Recherches Médicales de Franceville Centre Interdisciplinaire de Recherches Médicales de Franceville Laboratoire national de santé publique Centre Interdisciplinaire de Recherches Médicales de Franceville Centre Interdisciplinaire de Recherches Médicales de Franceville Centre Interdisciplinaire de Recherches Médicales de Franceville Laboratoire national de santé publique Centre Interdisciplinaire de Recherches Médicales de Franceville Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement University of Cape Town Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement Arizona State University [Tempe] Institut de Recherche pour le Développement Plant Health Institute of Montpellier

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Résumé : Plant virus ecology began to be explored at the end of the 19th century. Since then, major advances have revealed complex virus–host–vector interactions in a variety of environments. These advances have been accelerated by development of new technologies for virus detection and characterization, the latest of which being high-throughput sequencing (HTS). HTS technologies have proved to be effective for non-targeted characterization of all or nearly all viruses present in a sample without requiring prior information about virus identity, as would be needed for virus-targeted tests. Plant virus metagenomics studies have thus made important advances, including characterization of the complex interactions between phytovirus dynamics and the structure of multi-species host communities, and documentation of the effects of anthropogenic ecosystem simplification on plant virus emergence and diversity. However, such studies must overcome challenges at every stage, from plant sampling to bioinformatics analysis. Results of two recent studies will be presented. While the first study aimed at systematically evaluate plant-associated viromes across broad agroecological interfaces, the second study aimed at using a predator-enabled metagenomics strategy to sample the virome of a remote and difficult to access densely forested African tropical region.

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Fichiers liés : 609892.pdf

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• Type de publi. : Ouvrage (y compris édition critique et traduction)
• Date de publi. : 17/08/2023
• Auteurs : Anaïs TibiVincent MartinetAude VialatteAudrey AlignierValérie AngeonDavid A BohanDouadia BougheraraCordeau, S.Pierre CourtoisJean-Philippe DeguineJérôme EnjalbertFrédéric FabreHélène FrévilleBenoît GrimonprezNicolas GrossMourad HannachiMarie LaunayStéphane LemariéGilles MartelMireille NavarreteManuel PlantegenestVirginie RavignéAdrien RuschFrédéric SuffertSophie Thoyer
• Organismes : Direction de l'Expertise scientifique collective, de la Prospective et des Etudes Paris-Saclay Applied Economics Dynamiques et écologie des paysages agriforestiers Biodiversité agroécologie et aménagement du paysage Ecodéveloppement Agroécologie [Dijon] Centre d'Economie de l'Environnement - Montpellier Agroécologie [Dijon] Centre d'Economie de l'Environnement - Montpellier Peuplements végétaux et bioagresseurs en milieu tropical Département Systèmes Biologiques Génétique Quantitative et Evolution - Le Moulon (Génétique Végétale) Santé et agroécologie du vignoble Amélioration génétique et adaptation des plantes méditerranéennes et tropicales Centre d’études et de coopération juridique interdisciplinaire – Université de Poitiers [UR 20418] Unité Mixte de Recherche sur l'Ecosystème Prairial - UMR Sciences pour l'Action et le Développement : Activités, Produits, Territoires Agroclim Laboratoire d'Economie Appliquée de Grenoble Biodiversité agroécologie et aménagement du paysage Ecodéveloppement Institut de Génétique, Environnement et Protection des Plantes Plant Health Institute of Montpellier Département Systèmes Biologiques Santé et agroécologie du vignoble BIOlogie et GEstion des Risques en agriculture Centre d'Economie de l'Environnement - Montpellier

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Résumé : L’avènement des engrais et des pesticides de synthèse a permis aux agriculteurs de s’affranchir des contraintes environnementales limitant les rendements et s’est accompagnée d’une simplification des parcelles et des paysages agricoles. Les impacts environnementaux et sanitaires de ce modèle dominant, ainsi que ses interrelations avec le changement climatique et l’érosion de la biodiversité, sont désormais bien établis par la communauté scientifique. La demande sociétale pour une agriculture répondant aux besoins alimentaires, dans le respect de l’environnement et de la santé humaine, est de plus en plus forte, mais la transition des systèmes de culture est insuffisamment engagée. Le manque d’alternatives efficaces aux pesticides de synthèse pour protéger les cultures est notamment pointé pour justifier cette inertie. Cette expertise scientifique collective dresse un bilan des stratégies de protection des cultures fondées sur la diversification végétale des parcelles et des paysages agricoles, et analyse les freins et les leviers de leur déploiement. Elle s’inscrit dans l’axe « Recherche-Innovation » du plan Écophyto 2+ qui soutient la production des connaissances et outils nécessaires à la réduction de l’utilisation des pesticides de synthèse. Cet ouvrage s’adresse aux enseignants-chercheurs et aux étudiants, ainsi qu’aux acteurs du monde agricole, aux gestionnaires du territoire, organismes et associations environnementales et à tout citoyen intéressé par ces questions.

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• Type de publi. : Article dans une revue
• Date de publi. : 17/08/2023
• Auteurs : Jean-Baptiste ChansonFrançoise BouhourAnne-Catherine Aubé-NathierMartial MallaretChristophe VialAurélien HacquardPhilippe PetiotMarco SpinazziAleksandra Nadaj-PaklezaAndoni Echaniz-Laguna
• Organismes : Centre Hospitalier Universitaire [Strasbourg] Hôpital de Hautepierre [Strasbourg] Hospices Civils de Lyon Hôpital neurologique et neurochirurgical Pierre Wertheimer [CHU - HCL] Centre Hospitalier Universitaire d'Angers [GIN] Grenoble Institut des Neurosciences Hospices Civils de Lyon Hôpital neurologique et neurochirurgical Pierre Wertheimer [CHU - HCL] Cabinet de Neurologie Service d'Electroneuromyographie et Service de Neurologie C [Hôpital Pierre Wertheimer - HCL] Service de neurologie [Angers] Hôpitaux Universitaires de Strasbourg Université de Strasbourg Hôpital Bicêtre [GHU AP-HP. Université Paris-Saclay, Le Kremlin-Bicêtre] French National Reference Center for Rare Neuropathies Maladies et hormones du système nerveux
• Publié dans Journal of Neurology le 01/11/2020

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Résumé : Background: Myasthenia gravis (MG) is an autoimmune disease treated with acetylcholinesterase inhibitors and immunosuppressant/immunomodulatory drugs. MG is frequently diagnosed in elderly patients, a fragile population in which treatment adverse effects (TAE) have not been evaluated until now. Methods: We retrospectively analysed the files of all MG patients with disease onset after age 70 years in four French University Hospitals, including clinical, electrophysiological, biological, and treatment data, with an emphasis on TAE. MG outcomes were assessed using the Myasthenia Gravis Foundation of America (MGFA) status scale. Results: We included 138 patients (59% of men) with a mean follow-up of 4.5 years (range 1-19). Mean age at diagnosis was 78 years (70-93). Anti-acetylcholine receptor antibodies were found in 87% of cases, electrophysiological abnormalities in 82%, and thymoma in 10%. MG outcome was good in a majority of cases, with 76% of treated patients presenting with alleviated symptoms at follow-up. TAE were observed in 41% of patients, including severe TAE in 14% of cases. Seven patients (5.1%) died, including four (2.9%) from MG-related respiratory failure, and three (2.2%) from MG treatment-related complications, i.e., sepsis in 2 cases and brain toxoplasmosis in 1 case. TAE were observed in 53% of patients treated with azathioprine, 23% of patients treated with corticosteroids, and 15% of patients treated with mycophenolate mofetil. Conclusions: This retrospective study demonstrates MG in the elderly presents with a significant iatrogenic risk, including fatal immunosuppressant-related infections.

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• Type de publi. : Article dans une revue
• Date de publi. : 17/08/2023
• Auteurs : Anaïs MennecierBeauty MatokaMaria Melany Wilfred-TongaCatherine Chunda-LiyokaMwiya MwiyaNicolas NagotJean-Pierre MolèsPhilippe Van de PerreChipepo KankasaRachel King
• Organismes : Pathogenesis and Control of Chronic and Emerging Infections Pathogenesis and Control of Chronic and Emerging Infections Pathogenesis and Control of Chronic and Emerging Infections Pathogenesis and Control of Chronic and Emerging Infections Pathogenesis and Control of Chronic and Emerging Infections
• Publié dans Frontiers in Public Health le 21/10/2020

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Résumé : Background Infant post-natal prophylaxis (PNP) is used to prevent HIV transmission through breastfeeding. The WHO edited recommendations but so far there is no consensus on the duration of prophylaxis and the type of drug used depends on national guidelines. In Zambia, the national recommendations include a three-drug prophylaxis, composed of a dispersible combined tablet of zidovudine (AZT) and lamivudine (3TC) and an oral suspension of nevirapine (NVP) for 12 weeks or until the mother’s viral load is <1,000 cp/mL. The PROMISE-EPI study, modified the PNP regimen to lamivudine only, initiated at 6 weeks and continued until 12 months to all HIV exposed uninfected infants of virally unsuppressed mothers. Our aim in this analysis was to identify barriers and facilitators to this extended PNP, the keystone toward an effective prevention. Methods Individual interviews and focus group discussion (FGD) were conducted with PROMISE-EPI participants who had received prophylaxis for their children from the national program up to 6 weeks and then lamivudine oral solution in PROMISE-EPI study. Health care providers and PROMISE-EPI staff were also interviewed. Sessions were recorded, transcribed verbatim and translated from local languages into English. An initial code-book was designed and then adapted on the basis of the emerging themes, to allow a descriptive thematic analysis. Results More barriers to PNP adherence were identified with triple drug prophylaxis than with lamivudine. These barriers were related to the formulation and bitter taste of AZT/3TC tablets. The ready to use formulation and sweet taste of lamivudine syrup were appreciated by mothers. Extended PNP proposed in the PROMISE-EPI study was globally well accepted and strategies were found to increase adherence. Adherence to lamivudine appeared to be better than the mothers’ adherence to their own antiretroviral therapy. Conclusion Accompanying mothers living with HIV and giving them the choice of the PNP to prevent transmission via breastfeeding (type of PNP regimen and extended PNP in non-adherent mothers), may be one of the keys to reducing the burden of pediatric HIV acquisition in low and middle income countries.

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Fichiers liés : fpubh-11-1242904.pdf

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• Type de publi. : Article dans une revue
• Date de publi. : 15/08/2023
• Auteurs : Brigitte RanqueMor DiawAbdoul Karim DembeleClaudine LapoumeroulieLucile OffredoOumar TessougueSerigne Mourtalla GueyeDapa DialloSaliou DiopYves Colin‐aronoviczXavier JouvenOlivier Blanc‐brudePierre‐louis TharauxSylvain Le JeunePhilippe ConnesMarc RomanaCaroline Le van Kim
• Organismes : Université Paris Cité Unité Mixte Internationale "Environnement Santé Sociétés" Biologie Intégrée du Globule Rouge Laboratoire d'Excellence : Biogenèse et pathologies du globule rouge Centre National de Référence pour les Groupes Sanguins Biologie Intégrée du Globule Rouge Paris-Centre de Recherche Cardiovasculaire Centre de recherche et de lutte contre la drépanocytose Université Cheikh Anta Diop de Dakar [Sénégal] Paris-Centre de Recherche Cardiovasculaire Epidémiologie intégrative des maladies cardiovasculaires = Integrative epidemiology of cardiovascular diseases Paris-Centre de Recherche Cardiovasculaire Université Paris Cité Paris-Centre de Recherche Cardiovasculaire Université Paris Cité Paris-Centre de Recherche Cardiovasculaire Hôpital Avicenne [AP-HP] Laboratoire Interuniversitaire de Biologie de la Motricité Laboratoire d'Excellence : Biogenèse et pathologies du globule rouge Biologie Intégrée du Globule Rouge Biologie Intégrée du Globule Rouge
• Publié dans British Journal of Haematology le 29/10/2020

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Résumé : Summary Sickle cell anaemia (SCA) is a monogenic disease with a highly variable clinical course. We aimed to investigate associations between microvascular function, haemolysis markers, blood viscosity and various types of SCA‐related organ damage in a multicentric sub‐Saharan African cohort of patients with SCA. In a cross‐sectional study, we selected seven groups of adult patients with SS phenotype in Dakar and Bamako based on the following complications: leg ulcer, priapism, osteonecrosis, retinopathy, high tricuspid regurgitant jet velocity (TRV), macro‐albuminuria or none. Clinical assessment, echocardiography, peripheral arterial tonometry, laboratory tests and blood viscosity measurement were performed. We explored statistical associations between the biological parameters and the six studied complications. Among 235 patients, 58 had high TRV, 46 osteonecrosis, 43 priapism, 33 leg ulcers, 31 retinopathy and 22 macroalbuminuria, whereas 36 had none of these complications. Multiple correspondence analysis revealed no cluster of complications. Lactate dehydrogenase levels were associated with high TRV, and blood viscosity was associated with retinopathy and the absence of macroalbuminuria. Despite extensive phenotyping of patients, no specific pattern of SCA‐related complications was identified. New biomarkers are needed to predict SCA clinical expression to adapt patient management, especially in Africa, where healthcare resources are scarce.

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Fichiers liés : SCD study BioCadre - Association of haemolysis markers blood viscosity & microcirculation function with organ damage -2023 BJH.pdf

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• Type de publi. : Article dans une revue
• Date de publi. : 14/08/2023
• Auteurs : Laurence FaivreJean‐charles CrépinManon RédaDaphné LehalleVirginie CarmignacCaroline AbadieTristan MiraultCécile Faure‐conterJuliette Mazereeuw‐hautierAude MazaEve PuzenatMarie‐agnès Collonge‐rameAnne‐claire BursztejnChristophe PhilippeChristel Thauvin‐robinetMartin ChevarinClaire Abasq‐thomasJeanne AmielStéphanie ArpinSébastien BarbarotGeneviève BaujatDidier BessisEmmanuelle BourratOdile BouteNicolas ChassaingChristine CoubesBénédicte DemeerPatrick EderySalima El ChehadehAlice GoldenbergSmail Hadj‐rabiaDamien HayeBertrand IsidorMarie‐line JacquemontPhilippe KHAU VAN KIENDidier LacombeDaphné LehalleLaetitia LambertLudovic MartinA MaruaniFanny Morice‐picardFlorence PetitAlice PhanLucile PinsonMassimiliano RossiRenaud TouraineClémence VanlerbergheMarie VincentCatherine Vincent‐delormeSandra WhalenMarjolaine WillemsNathalie MarleVirginie VerkarreChristine DevallandMojgan Devouassoux‐shisheboranMarine AbadNathalie Rioux‐leclercqBertille BonniaudYannis DuffourdJehanne MartelC BinquetPaul KuentzPierre Vabres
• Organismes : Centre de génétique - Centre de référence des maladies rares, anomalies du développement et syndromes malformatifs (CHU de Dijon) Centre Hospitalier Universitaire de Dijon - Hôpital François Mitterrand Lipides - Nutrition - Cancer [Dijon - U1231] Centre Hospitalier Universitaire de Rennes [CHU Rennes] = Rennes University Hospital [Pontchaillou] Université Paris Cité École Doctorale Bio Sorbonne Paris Cité [Paris] GHU AP-HP Centre Université Paris Cité Hôpital Européen Georges Pompidou [APHP] Service de médecine vasculaire et hypertension artérielle [CHU HEGP] Filière de santé maladies rares : maladies vasculaires rares avec atteinte multisystémique [CHU Paris Nord-Val de Seine] Centre de Référence des Maladies Vasculaires Rares [HEGP, APHP] Paris-Centre de Recherche Cardiovasculaire CHU Montpellier = Montpellier University Hospital Centre Hospitalier Universitaire de Toulouse Centre de référence des maladies rares de la peau et des muqueuses d’origine génétique [CHU Toulouse] Département de dermatologie Centre Hospitalier Régional Universitaire de Nancy Equipe GAD (LNC - U1231) FHU TRANSLAD (CHU de Dijon) Laboratoire sur les interactions Epithéliums Neurones Imagine - Institut des maladies génétiques (IHU) Hôpital Necker - Enfants Malades [AP-HP] Service de génétique [CHRU Tours] Physiopathologie des Adaptations Nutritionnelles Institut Necker Enfants-Malades CHU Amiens-Picardie CHirurgie, IMagerie et REgénération tissulaire de l’extrémité céphalique - Caractérisation morphologique et fonctionnelle - UR UPJV 7516 Institut des Biomolécules Max Mousseron [Pôle Chimie Balard] Laboratoire de Cytologie Clinique et de Cytogénétique [CHU Nîmes] Hospices Civils de Lyon Service de Génétique [HCL, Lyon]
• Publié dans Clinical Genetics le 30/10/2020

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Résumé :

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Fichiers liés : Faivre et al. 2022.pdf

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• Type de publi. : Article dans une revue
• Date de publi. : 10/08/2023
• Auteurs : Louis-Philippe CoulombeBjörn BennekeRyan ChallenerAnjali PietteLindsey WiserMegan MansfieldRyan MacdonaldHayley BeltzAdina FeinsteinMichael RadicaArjun SavelLeonardo dos SantosJacob BeanVivien ParmentierIan WongEmily RauscherThaddeus KomacekEliza M.-R. KemptonXianyu TanMark HammondNeil LewisMichael LineElspeth LeeHinna ShivkumarIan CrossfieldMatthew NixonBenjamin RackhamHannah WakefordLuis WelbanksXi ZhangNatalie BatalhaZachory Berta-ThompsonQuentin ChangeatJean-Michel DésertNéstor EspinozaJayesh GoyalJoseph HarringtonHeather KnutsonLaura KreidbergMercedes López-MoralesAvi ShporerDavid SingKevin StevensonKeshav AggarwalEva-Maria AhrerMunazza AlamTaylor BellJasmina BlecicClaudio CaceresAarynn CarterSarah CasewellNicolas CrouzetPatricio CubillosLeen DecinJonathan FortneyNeale GibsonKevin HengThomas HenningNicolas IroSarah KendrewPierre-Olivier LagageJérémy LeconteMonika LendlJoshua LothringerLuigi ManciniThomas Mikal-EvansKaran MolaverdikhaniNikolay NikolovKazumasa OhnoEnric PalleCaroline PiauletSeth RedfieldPierre-Alexis RoyShang-Min TsaiOlivia VenotPeter Wheatley
• Organismes : Laboratoire Interuniversitaire des Systèmes Atmosphériques
• Publié dans Nature le 29/10/2020

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Résumé : Abstract Close-in giant exoplanets with temperatures greater than 2,000 K (‘ultra-hot Jupiters’) have been the subject of extensive efforts to determine their atmospheric properties using thermal emission measurements from the Hubble Space Telescope (HST) and Spitzer Space Telescope 1–3 . However, previous studies have yielded inconsistent results because the small sizes of the spectral features and the limited information content of the data resulted in high sensitivity to the varying assumptions made in the treatment of instrument systematics and the atmospheric retrieval analysis 3–12 . Here we present a dayside thermal emission spectrum of the ultra-hot Jupiter WASP-18b obtained with the NIRISS 13 instrument on the JWST. The data span 0.85 to 2.85 μm in wavelength at an average resolving power of 400 and exhibit minimal systematics. The spectrum shows three water emission features (at >6 σ confidence) and evidence for optical opacity, possibly attributable to H − , TiO and VO (combined significance of 3.8 σ ). Models that fit the data require a thermal inversion, molecular dissociation as predicted by chemical equilibrium, a solar heavy-element abundance (‘metallicity’, $${\rm{M/H}}=1.0{3}_{-0.51}^{+1.11}$$ M/H = 1.0 3 − 0.51 + 1.11 times solar) and a carbon-to-oxygen (C/O) ratio less than unity. The data also yield a dayside brightness temperature map, which shows a peak in temperature near the substellar point that decreases steeply and symmetrically with longitude towards the terminators.

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Fichiers liés : 2301.08192.pdf

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