11 research outputs found
Transiting exoplanets from the CoRoT space mission VIII. CoRoT-7b: the first Super-Earth with measured radius
We report the discovery of very shallow (DF/F = 3.4 10-4), periodic dips in
the light curve of an active V = 11.7 G9V star observed by the CoRoT satellite,
which we interpret as due to the presence of a transiting companion. We
describe the 3-colour CoRoT data and complementary ground-based observations
that support the planetary nature of the companion. Methods. We use CoRoT color
information, good angular resolution ground-based photometric observations in-
and out- of transit, adaptive optics imaging, near-infrared spectroscopy and
preliminary results from Radial Velocity measurements, to test the diluted
eclipsing binary scenarios. The parameters of the host star are derived from
optical spectra, which were then combined with the CoRoT light curve to derive
parameters of the companion. We examine carefully all conceivable cases of
false positives, and all tests performed support the planetary hypothesis.
Blends with separation larger than 0.40 arcsec or triple systems are almost
excluded with a 8 10-4 risk left. We conclude that, as far as we have been
exhaustive, we have discovered a planetary companion, named CoRoT-7b, for which
we derive a period of 0.853 59 +/- 3 10-5 day and a radius of Rp = 1.68 +/-
0.09 REarth. Analysis of preliminary radial velocity data yields an upper limit
of 21 MEarth for the companion mass, supporting the finding.
CoRoT-7b is very likely the first Super-Earth with a measured radius.Comment: Accepted in Astronomy and Astrophysics; typos and language
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Transiting exoplanets from the CoRoT space mission. VIII. CoRoT-7b: the first super-Earth with measured radius
Copyright © The European Southern Observatory (ESO)Aims. We report the discovery of very shallow (ΔF/F ≈ 3.4×10−4), periodic dips in the light curve of an active V = 11.7 G9V star observed by the CoRoT satellite, which we interpret as caused by a transiting companion. We describe the 3-colour CoRoT data and complementary ground-based observations that support the planetary nature of the companion.
Methods. We used CoRoT colours information, good angular resolution ground-based photometric observations in- and out- of transit, adaptive optics imaging, near-infrared spectroscopy, and preliminary results from radial velocity measurements, to test the diluted eclipsing binary scenarios.
The parameters of the host star were derived from optical spectra, which were then combined with the CoRoT light curve to derive parameters of the companion.
Results. We examined all conceivable cases of false positives carefully, and all the tests support the planetary hypothesis. Blends with separation >0.40'' or triple systems are almost excluded with a 8 × 10−4 risk left. We conclude that, inasmuch we have been exhaustive, we have discovered a planetary companion, named CoRoT-7b, for which we derive a period of 0.853 59 ± 3 × 10−5 day and a radius of Rp = 1.68 ± 0.09 REarth. Analysis of preliminary radial velocity data yields an upper limit of 21 MEarth for the companion mass, supporting the finding.
Conclusions. CoRoT-7b is very likely the first Super-Earth with a measured radius. This object illustrates what will probably become a common situation with missions such as Kepler, namely the need to establish the planetary origin of transits in the absence of a firm radial velocity detection and mass measurement. The composition of CoRoT-7b remains loosely constrained without a precise mass. A very high surface temperature on its irradiated face, ≈1800–2600 K at the substellar point, and a very low one, ≈50 K, on its dark face assuming no atmosphere, have been derived
Pediatric intervention study with a polar lipid enriched milk (Inpulse (R)) product on resistance to common infectious diseases and well-being
Impact de la qualité lipidique des formules infantiles sur les fonctions cérébrales dans un modèle d’allaitement artificiel chez le raton : effets des lipides laitiers et de la supplémentation en acides docosahexaénoïque et arachidonique
International audience(A. Deglaire) Introduction et but de l'étude Le lait maternel est l'aliment idéal pour le nouveau-né, particulièrement chez le prématuré (OMS, 2015). Il peut être pas-teurisé pour des raisons sanitaires, ce qui peut notamment modifier les cinétiques globales de protéolyse [1–3]. L'objectif de cette étude était d'évaluer l'impact de la pasteurisation du lait maternel sur les cinétiques de libération des produits intermédiaires de protéolyse, c'est-à-dire les peptides. Matériel et méthodes Douze enfants prématurés hospitalisés (30,0 ± 1,0 semaines d'aménorrhée ; 1,4 ± 0,3 kg), nourris par sonde gastrique, ont participé à cette étude randomisée (NCT02112331). Sur 6 jours consécutifs, chaque enfant recevait le même jour deux repas tests à base de lait maternel cru ou pasteurisé. Les effluents gastriques étaient collectés en double à 35, 60 ou 90 min. Le lait avant digestion et les effluents étaient analysés semi-quantitativement en spec-trométrie de masse tandem, après séparation par nanochromatographie. Après transformation des données et application pour chaque peptide d'un modèle linéaire mixte (facteurs : temps, repas, repas × temps, jour [temps], poids corpo-rel, teneur en protéines du lait et sujet), une classification hiérarchique ascendante était réalisée sur les coefficients d'interaction « repas × temps » et des groupes de peptides étaient ainsi identifiés (logiciel R). Résultats La classification de 1579 peptides (six à 51 acides aminés ; caséine-: 58 %, lactoferrine : 10 %), mettait en évidence cinq groupes, caractérisé
Efficacité d'une eau gélifiée et d'une poudre épaississante destinées aux patients dysphagiques aux liquides : une étude randomisée et en cross over
International audienc
La chirurgie bariatrique affecte les besoins en protéines liés à l'obésité
FONCTION INTESTINALE ET OBÉSITÉIntroduction et but de l’étude: Après chirurgie bariatrique, un déficit en protéines est fréquemment rapporté chez les patients souffrant d'obésité morbide alors que les besoins en protéines n’ont pas été précisément déterminés dans cette population. L'objectif de cette étude est d'évaluer le besoin protéique moyen (BPM) chez les sujets obèses, avant, 3 mois et 12 mois après la chirurgie bariatrique en utilisant la méthode de bilan azoté.Matériel et méthodes: Une étude longitudinale prospective, incluant 21 patients en obésité morbide (IMC 43,9±1,4 kg/m²) a été mise en place pour évaluer le bilan azoté calculé à partir des mesures des apports alimentaires et des pertes d'azote dans les urines et les selles collectées durant 3 jours avant (M0), 3 mois (M3) et 12 mois (M12) après sleeve gastrectomie ou by-pass gastrique. Une régression linéaire entre les apports en protéines et le bilan azoté a été utilisée pour déterminer la valeur du BPM. Une étude transversale plus large a été réalisée pour valider le BPM chez des patients obèses appariés non opérés (n = 106). Les valeurs de BPM sont exprimées en moyenne [Intervalle de confiance (IC) à 95%] et les autres valeurs en moyenne ± écart-type à la moyenne.Résultats et Analyse statistique : Avant la chirurgie, le BPM des patients obèses était de 0,76 [IC à 95%, 0,66-0,92] g/kg de poids corporel/j dans le groupe expérimental et de 0,74 [0,70-0,80] g/kg/j dans le groupe de validation. Il était de 0,62 [0,51-0,75] g/kg/j à M3 et de 0,87 [0,75-0,98] g/kg/j à M12, sans différence entre les procédures chirurgicales. Les apports spontanés en protéines étaient respectivement de 0,80±0,05; 0,43±0,03; 0,71±0,04 g/kg/j respectivement à M0, M3 et M12.Conclusion: Cette étude indique un changement temporel des besoins en protéines après chirurgie bariatrique quel que soit le type de chirurgie. Les apports spontanés après chirurgie bariatrique ne couvrent pas les besoins en protéines de la plupart des patients, ce qui suggère que des recommandations spécifiques sur les protéines alimentaires doivent être adaptées chez les patients obèses candidats à une chirurgie bariatrique
Weaning of Wild Young-of-the-Year Winter Flounder Pleuronectes americanus (Walbaum) on a Dry Diet: Effects on Growth, Survival, and Feed Efficiency Ratios
Dairy and industrial sources of trans fat do not impair peripheral insulin sensitivity in overweight women
International audienceBackground: The 2 major dietary sources of trans fatty acids (TFAs) are partially hydrogenated oils and ruminant-derived products. Epidemiologic data suggest that chronic consumption of industrial sources of TFAs could be damaging to insulin sensitivity, but intervention studies on this issue have remained inconclusive. Objective: The trial was designed to compare the effects of dairy compared with industrial sources of TFAs on insulin sensitivity in overweight women. Design: Sixty-three healthy women with abdominal obesity [waist circumference > 88 cm and a body mass index (in kg/m(2)) > 28] were recruited. After a run-in period, the volunteers were randomly assigned to consume 1 of 3 four-week diets: 60 g low-TFA lipids/d (0.54 g/d; n = 21), ruminant TFA-rich lipids (4.86 g/d; n = 21), or industrial TFA-rich lipids (5.58 g/d; n = 21). Changes in peripheral insulin sensitivity were assessed by using hyperinsulinemiceuglycemic clamps. Results: After the intervention period, fasting glycemia and insulinemia and insulin sensitivity were not significantly modified in either group (P > 0.05). Conclusions: These data indicate that consumption of dairy- and industrial-source TFAs for 4 wk at nutritional levels do not impair peripheral insulin sensitivity in insulin-resistant women. Our study may not preassess the effects of TFAs in normal insulin-sensitive individuals. This trial was registered at clinicaltrials.gov as NCT00617435. Am J Clin Nutr 2009;90:88-94
The CoRoT satellite in flight: description and performance
International audienceContext. CoRoT is a space telescope dedicated to stellar seismology and the search for extrasolar planets. The mission is led by the CNES in association with French laboratories and has a large international participation. The European Space Agency (ESA), Austria, Belgium, and Germany contribute to the payload, and Spain and Brazil contribute to the ground segment. Development of the spacecraft, which is based on a PROTEUS low earth orbit (LEO) recurrent platform, commenced in October 2000, and the satellite was launched on December 27, 2006. Aims. The instrument and platform characteristics prior to launch have been described in ESA publication (SP-1306). In the present paper we explain the behaviour in flight, based on raw and corrected data. Methods. Five runs have been completed since January 2007. The data used here are essentially those acquired during the commissioning phase and from a long run that lasted 146 days. These enable us to give a complete overview of the instrument and platform behaviour for all environmental conditions. The ground based data processing is not described in detail because the most important method has been published elsewhere. Results. We show that the performance specifications are easily satisfied when the environmental conditions are favourable. Most of the perturbations, hence data corrections, are related to LEO perturbations: high energy particles inside the South Atlantic Anomaly (SAA), eclipses and temperature variations, and line of sight fluctuations due to the attitude control system. Straylight due to the reflected light from the earth, which is controlled by the telescope and baffle design, appears to be negligible