A chemical survey of exoplanets with ARIEL

Thousands of exoplanets have now been discovered with a huge range of masses, sizes and orbits: from rocky Earth-like planets to large gas giants grazing the surface of their host star. However, the essential nature of these exoplanets remains largely mysterious: there is no known, discernible pattern linking the presence, size, or orbital parameters of a planet to the nature of its parent star. We have little idea whether the chemistry of a planet is linked to its formation environment, or whether the type of host star drives the physics and chemistry of the planet’s birth, and evolution. ARIEL was conceived to observe a large number (~1000) of transiting planets for statistical understanding, including gas giants, Neptunes, super-Earths and Earth-size planets around a range of host star types using transit spectroscopy in the 1.25–7.8 μm spectral range and multiple narrow-band photometry in the optical. ARIEL will focus on warm and hot planets to take advantage of their well-mixed atmospheres which should show minimal condensation and sequestration of high-Z materials compared to their colder Solar System siblings. Said warm and hot atmospheres are expected to be more representative of the planetary bulk composition. Observations of these warm/hot exoplanets, and in particular of their elemental composition (especially C, O, N, S, Si), will allow the understanding of the early stages of planetary and atmospheric formation during the nebular phase and the following few million years. ARIEL will thus provide a representative picture of the chemical nature of the exoplanets and relate this directly to the type and chemical environment of the host star. ARIEL is designed as a dedicated survey mission for combined-light spectroscopy, capable of observing a large and well-defined planet sample within its 4-year mission lifetime. Transit, eclipse and phase-curve spectroscopy methods, whereby the signal from the star and planet are differentiated using knowledge of the planetary ephemerides, allow us to measure atmospheric signals from the planet at levels of 10–100 part per million (ppm) relative to the star and, given the bright nature of targets, also allows more sophisticated techniques, such as eclipse mapping, to give a deeper insight into the nature of the atmosphere. These types of observations require a stable payload and satellite platform with broad, instantaneous wavelength coverage to detect many molecular species, probe the thermal structure, identify clouds and monitor the stellar activity. The wavelength range proposed covers all the expected major atmospheric gases from e.g. H2O, CO2, CH4 NH3, HCN, H2S through to the more exotic metallic compounds, such as TiO, VO, and condensed species. Simulations of ARIEL performance in conducting exoplanet surveys have been performed – using conservative estimates of mission performance and a full model of all significant noise sources in the measurement – using a list of potential ARIEL targets that incorporates the latest available exoplanet statistics. The conclusion at the end of the Phase A study, is that ARIEL – in line with the stated mission objectives – will be able to observe about 1000 exoplanets depending on the details of the adopted survey strategy, thus confirming the feasibility of the main science objectives.Peer reviewedFinal Published versio

Figurationen des Porträts

Mit dem Fokus auf Figurationen des Porträts wird ein Spannungsfeld kulturellen Wissens eröffnet, anhand dessen sich der historische Bezugsraum von Artefakten diskutieren lässt. Porträt meint also nicht (nur) die kunsthistorische Gattung, sondern ein Wahrnehmungsmodell, das sich zwischen einmaliger Ausprägung und der Wiedererkennbarkeit der Form entfaltet. Die Studien zielen in einem Bogen vom frühesten (Herrscher-) Porträt aus dem Alten Mesopotamien bis in die Gegenwartskunst hinein auf historisch variable Formen, individuelles Leben als besonders darzustellen. Neben genuin bild- und skulpturorientierten Beiträgen von antiken Centauren-Porträts und Statuenbasen im kaiserzeitlichen Sagalassos über die ›Antike der Fotografie‹ bis hin zu Schwitters’ Merzbild 9b und Twomblys Selbstbildnissen behandeln textorientierte Beiträge Fragen der Lesbarkeit von Porträts, etwa in apokryphen Paulus-Texten, an der Schnittstelle von biographischem Porträt und byzantinischer Philosophie oder anhand von Poes Oval Portrait. Ein eigener Fokus gilt den kulturellen Praktiken der Bedeutungsstiftung, von Stalins Herrscherbildnissen bis hin zur anthropologischen Funktion beispielsweise von Masken

Demographic, clinical and antibody characteristics of patients with digital ulcers in systemic sclerosis: data from the DUO Registry

OBJECTIVES: The Digital Ulcers Outcome (DUO) Registry was designed to describe the clinical and antibody characteristics, disease course and outcomes of patients with digital ulcers associated with systemic sclerosis (SSc). METHODS: The DUO Registry is a European, prospective, multicentre, observational, registry of SSc patients with ongoing digital ulcer disease, irrespective of treatment regimen. Data collected included demographics, SSc duration, SSc subset, internal organ manifestations, autoantibodies, previous and ongoing interventions and complications related to digital ulcers. RESULTS: Up to 19 November 2010 a total of 2439 patients had enrolled into the registry. Most were classified as either limited cutaneous SSc (lcSSc; 52.2%) or diffuse cutaneous SSc (dcSSc; 36.9%). Digital ulcers developed earlier in patients with dcSSc compared with lcSSc. Almost all patients (95.7%) tested positive for antinuclear antibodies, 45.2% for anti-scleroderma-70 and 43.6% for anticentromere antibodies (ACA). The first digital ulcer in the anti-scleroderma-70-positive patient cohort occurred approximately 5 years earlier than the ACA-positive patient group. CONCLUSIONS: This study provides data from a large cohort of SSc patients with a history of digital ulcers. The early occurrence and high frequency of digital ulcer complications are especially seen in patients with dcSSc and/or anti-scleroderma-70 antibodies

Conception et évaluation de systèmes de culture mobilisant les leviers préventifs de la gestion des adventices – Cas du groupe de développement de Brienne

National audienc

Combining expert knowledge and models in participatory workshops with farmers to design sustainable weed management strategies

International audienceIn order to design cropping systems reconciling cropproduction, biodiversity and reduced herbicide use, weorganized participatory workshops with farmers in theChampagne region (North-Eastern France). Methodscombined cropping-system prototyping by farmers, expertopinion and models. In a first meeting, farmers determinedtheir objectives and constraints, and chose areference system existing in one of their farms (oilseedrape/winter wheat/winter wheat/spring barley heavilyinfested by autumnal grass weeds). In a secondmeeting, two sets of prototypes were designed by twoseparate groups, using the Mission Ecophyt’eau® tool(https://ecophytopic.fr/pour-aller-plus-loin/outil-mission-ecophyteaur) as support.The reference and the prototypes were evaluated interms of (1) technical feasability from farmers’ andscientists’ expertise, (2) weed harmfulness for cropproduction and weed contribution to biodiversity withFlorSys which simulates crop and weed growth and reproductionin cropping systems at a daily time step overseveral years (Colbach et al., Weed Res 2014), and (3)economic, social and environmental sustainability withthe DEXiPM (Pelzer et al, Ecol Indicators 2012) model.Steps 2 and 3 were carried out after the meeting. Ata third meeting, these results were presented to thefarmers who continued improving the prototypes, usingthe DeciFlorSys model which includes decision treesto guide farmers during cropping-system design and afast calculator estimating weed harmfulness and biodiversityof cropping system prototyes (Colas et al., Eur JAgron 2020). Both prototypes presented increased cropdiversification, introducing legumes and other broadleavedcrops, crop mixtures and cover crops. PrototypeA was based on reduced tillage and annual crops only.Prototype B also included multi-annual lucerne andoptimised both tillage and mechanical weeding. Bothprototypes reduced weed harmfulness for crop production(yield loss, harvest contamination, field infestation)and herbicide use intensity (approx. -60%) comparedto the reference system. Prototype B also improvedweed-based trophic resources for carabids and pollinators.The best solution was a suboption of prototypeB replacing most of the herbicides by mechanicalweeding, dividing yield loss by nearly two comparedto the reference and improving biodiversity by 5-10%.The workshop participants appreciated the knowledgeon agroecosystem functioning and the complementarityof models: DeciFlorSys allowed a direct evaluationduring workshops, FlorSys produced a detailed diagnosisof the technical and meteorological causes of thecropping systems’ performance and DEXiPM assessedworking times and economic viability of the prototypes.Following the workshops, some participants investedin new implements for mechanical weeding and introducedmore spring crops into their rotations

Le développement du modèle intégré des hydrosystèmes Eau-dyssée : Rapport PIREN SEINE

L’étude des scénarios d’évolution de la ressource en eau (des points de vue qualitatif et quantitatif) selon les différentes contraintes climatiques, économiques ou technologiques passe de plus en plus par la modélisation intégrée des hydrosystèmes. Le projet Eau-dyssée vise au développement d’un tel outil, en s’appuyant sur des modèles disciplinaires et sur l’utilisation du coupleur externe Palm (Piacentini et al, 2003). On se base dans un premier temps sur 4 modèles disciplinaires qui sont en cours d’intégration : le modèle hydrologique MODCOU, le modèle agronomique Stics, le modèle d’offre agronomique AROPA-j, et le schéma de surface atmosphérique Surfex (précédemment ISBA). Ces différents modèles ont déjà fait l’objet de couplages partiels (AROPA-j Stics, ISBA-MODCOU, ISBAStics, Stics-MODCOU). Cependant, ces couplages étaient peu interactifs (il s’agissait bien souvent d’un simple forçage, sans rétroaction possible) et souvent peu évolutifs du fait des modifications insérées pour réaliser ces forçages. Eau-dyssée vise donc au développement d’un couplage interactif, évolutif et modulaire entre modèles experts. Une première phase dans la construction d’Eau-dyssée a consisté à restructurer MODCOU pour le rendre plus modulaire et lui permettre de gérer de multiples interactions (Habets et al., 2008). Une deuxième phase qui vient juste de commencer consiste à réaliser le couplage entre MODCOU et les 3 autres modèles experts au sein d’Eau-dyssée. Cela passe d’abord par la prise en main de ces modèles experts, et par des tests de sensibilités avant d’en arriver au couplage. Ce rapport fait donc le point sur l’état du développement d’Eau-dyssée, avec tout d’abord, les modifications introduites dans le modèle hydrologique MODCOU, puis, le point sur les couplages avec les autres modèles experts