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See detailPlanetary transit candidates in CoRoT-LRc01 field
Cabrera, J.; Fridlund, M.; Ollivier, M. et al

in Astronomy and Astrophysics (2009), 506

Aims: We present here the list of planetary transit candidates detected in the first long run observed by CoRoT: LRc01, towards the galactic center in the direction of Aquila, which lasted from May to ... [more ▼]

Aims: We present here the list of planetary transit candidates detected in the first long run observed by CoRoT: LRc01, towards the galactic center in the direction of Aquila, which lasted from May to October 2007. <BR />Methods: we analyzed 3719 (33%) sources in the chromatic bands and 7689 in the monochromatic band. Instrumental noise and the stellar variability were treated with several detrending tools, on which subsequently several transit search algorithms were applied. <BR />Results: Forty two sources were classified as planetary transit candidates and up to now 26 cases have been solved. One planet (CoRoT-2b) and one brown-dwarf (CoRoT-3b) have been the subjects of detailed publications. The CoRoT space mission, launched on December 27 2006, was developed and is operated by CNES, with contributions from Austria, Belgium, Brazil, ESA, Germany and Spain. The first CoRoT data are available to the community from the CoRoT archive: http://idoc-corot.ias.u-psud.fr. [less ▲]

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See detailPost-AGB stars with hot circumstellar dust: binarity of the low-amplitude pulsators
van Winckel, H.; Lloyd Evans, T.; Briquet, Maryline ULg et al

in Astronomy and Astrophysics (2009), 505

Context: The influence of binarity on the late stages of stellar evolution remains an open issue. <BR />Aims: While the first binary post-AGB stars were serendipitously discovered, the distinct ... [more ▼]

Context: The influence of binarity on the late stages of stellar evolution remains an open issue. <BR />Aims: While the first binary post-AGB stars were serendipitously discovered, the distinct characteristics of their spectral energy distribution (SED) allowed us to launch a more systematic search for binaries. We selected post-AGB objects, which exhibit a broad dust excess starting either at H or K, pointing to the presence of a gravitationally bound dusty disc in the system. We initiated an extensive multiwavelength study of those systems and here report on our radial velocity and photometric monitoring results for six stars of early F type, which are pulsators of small amplitude. <BR />Methods: To determine the radial velocity of low signal-to-noise ratio time-series data, we constructed dedicated autocorrelation masks based on high signal-to-noise ratio spectra, used in our published chemical studies. The radial velocity variations were analysed in detail to differentiate between pulsational variability and variability caused by orbital motion. When available, the photometric monitoring data were used to complement the time series of radial velocity data and to establish the nature of the pulsation. Finally, orbital minimalisation was performed to constrain the orbital elements. <BR />Results: All of the six objects are binaries with orbital periods ranging from 120 to 1800 days. Five systems have non-circular orbits. The mass functions range from 0.004 to 0.57 M[SUB]&sun;[/SUB] and the companions are probably unevolved objects of (very) low initial mass. We argue that these binaries must have evolved through a phase of strong binary interaction when the primary was a cool supergiant. Although the origin of the circumstellar disc is not well understood, the disc is generally believed to have formed during this strong interaction phase. The eccentric orbits of these highly evolved objects remain poorly understood. In one object, the line-of-sight grazes the edge of the puffed-up inner rim of the disc. <BR />Conclusions: These results corroborate our earlier statement that evolved objects in binary stars create a Keplerian dusty circumbinary disc. With the measured orbits and mass functions, we conclude that the circumbinary discs seem to have a major impact on the evolution of a significant fraction of binary systems. based on observations collected with the Flemish 1.2 m Mercator telescope at Roque de los Muchachos (Spain), the Swiss 1.2 m Euler telescope at La Silla (Chile) and the 0.5 m and 0.75 m telescopes at SAAO (South-Africa). Tables [see full textsee full text]-[see full textsee full text] are only available in electronic form at http://www.aanda.org Postdoctoral fellow of the Fund for Scientific Research, Flanders. Ph.D. student of the Fund for Scientific Research, Flanders. [less ▲]

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See detailNoise properties of the CoRoT data. A planet-finding perspective
Aigrain, S.; Pont, F.; Fressin, F. et al

in Astronomy and Astrophysics (2009), 506

In this short paper, we study the photometric precision of stellar light curves obtained by the CoRoT satellite in its planet-finding channel, with a particular emphasis on the time scales characteristic ... [more ▼]

In this short paper, we study the photometric precision of stellar light curves obtained by the CoRoT satellite in its planet-finding channel, with a particular emphasis on the time scales characteristic of planetary transits. Together with other articles in the same issue of this journal, it forms an attempt to provide the building blocks for a statistical interpretation of the CoRoT planet and eclipsing binary catch to date. After pre-processing the light curves so as to minimise long-term variations and outliers, we measure the scatter of the light curves in the first three CoRoT runs lasting more than 1 month, using an iterative non-linear filter to isolate signal on the time scales of interest. The behaviour of the noise on 2 h time scales is described well by a power-law with index 0.25 in R-magnitude, ranging from 0.1 mmag at R=11.5 to 1 mmag at R=16, which is close to the pre-launch specification, though still a factor 2-3 above the photon noise due to residual jitter noise and hot pixel events. There is evidence of slight degradation in the performance over time. We find clear evidence of enhanced variability on hour time scales (at the level of 0.5 mmag) in stars identified as likely giants from their R magnitude and B-V colour, which represent approximately 60 and 20% of the observed population in the directions of Aquila and Monoceros, respectively. On the other hand, median correlated noise levels over 2 h for dwarf stars are extremely low, reaching 0.05 mmag at the bright end. The CoRoT space mission, launched on December 27, 2006, has been developed and is operated by the CNES, with the contribution of Austria, Belgium, Brazil, ESA, Germany, and Spain. CoRoT data become publicly available one year after release to the Co-Is of the mission from the CoRoT archive: http://idoc-corot.ias.u-psud.fr/. [less ▲]

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See detailPlanetary transit candidates in Corot-IRa01 field
Carpano, S.; Cabrera, J.; Alonso, R. et al

in Astronomy and Astrophysics (2009), 506

Context: CoRoT is a pioneering space mission devoted to the analysis of stellar variability and the photometric detection of extrasolar planets. <BR />Aims: We present the list of planetary transit ... [more ▼]

Context: CoRoT is a pioneering space mission devoted to the analysis of stellar variability and the photometric detection of extrasolar planets. <BR />Aims: We present the list of planetary transit candidates detected in the first field observed by CoRoT, IRa01, the initial run toward the Galactic anticenter, which lasted for 60 days. <BR />Methods: We analysed 3898 sources in the coloured bands and 5974 in the monochromatic band. Instrumental noise and stellar variability were taken into account using detrending tools before applying various transit search algorithms. <BR />Results: Fifty sources were classified as planetary transit candidates and the most reliable 40 detections were declared targets for follow-up ground-based observations. Two of these targets have so far been confirmed as planets, CoRoT-1b and CoRoT-4b, for which a complete characterization and specific studies were performed. The CoRoTâ space mission, launched on December 27th 2006, has been developed and is operated by CNES, with contributions from Austria, Belgium, Brazil, ESA, Germany, and Spain. Four French laboratories associated with the CNRS (LESIA, LAM, IAS ,OMP) collaborate with CNES on the satellite development. First CoRoT data are available to the public from the CoRoT archive: http://idoc-corot.ias.u-psud.fr. [less ▲]

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See detailThe secondary eclipse of CoRoT-1b
Alonso, R.; Alapini, A.; Aigrain, S. et al

in Astronomy and Astrophysics (2009), 506

The transiting planet CoRoT-1b is thought to belong to the pM-class of planets, in which the thermal emission dominates in the optical wavelengths. We present a detection of its secondary eclipse in the ... [more ▼]

The transiting planet CoRoT-1b is thought to belong to the pM-class of planets, in which the thermal emission dominates in the optical wavelengths. We present a detection of its secondary eclipse in the CoRoT white channel data, whose response function goes from ~400 to ~1000 nm. We used two different filtering approaches, and several methods to evaluate the significance of a detection of the secondary eclipse. We detect a secondary eclipse centered within 20 min at the expected times for a circular orbit, with a depth of 0.016 ± 0.006%. The center of the eclipse is translated in a 1-Ï upper limit to the planet's eccentricity of e cosÏ < 0.014. Under the assumption of a zero Bond Albedo and blackbody emission from the planet, it corresponds to a T_CoRoT = 2330[SUP]+120[/SUP][SUB]-140[/SUB] K. We provide the equilibrium temperatures of the planet as a function of the amount of reflected light. If the planet is in thermal equilibrium with the incident flux from the star, our results imply an inefficient transport mechanism of the flux from the day to the night sides. Based on observations obtained with CoRoT, a space project operated by the French Space Agency, CNES, with participation of the Science Programme of ESA, ESTEC/RSSD, Austria, Belgium, Brazil, Germany and Spain. [less ▲]

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See detailUn phénomène de double négation : οὐ μή suivis du futur ou du subjonctif
Denizot, Camille ULg

in Syntaktika (2009), 38

La double négation οὐ μή s’emploie devant un subjonctif pour une forte dénégation et devant un futur, dans une interrogation, pour une prohibition. Les éditions hésitent parfois entre les deux expressions ... [more ▼]

La double négation οὐ μή s’emploie devant un subjonctif pour une forte dénégation et devant un futur, dans une interrogation, pour une prohibition. Les éditions hésitent parfois entre les deux expressions, notamment en raison de la proximité morphologique du subjonctif et du futur. À partir d’un examen exhaustif des occurrences chez les trois Tragiques, Aristophane et Platon, on peut montrer que les deux tournures sont sémantiquement et syntaxiquement différentes, particulièrement en ce qui concerne le fonctionnement et la portée des deux négations dans ces deux expressions. [less ▲]

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See detailVariations in sound production in <i>Dascyllus flavicaudus<i>
Kever, Loïc ULg; Lecchini, David; Parmentier, Eric ULg

Poster (2009, October)

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See detailComparaison de 5 techniques de prération du PRP (Platelet-Rich Plasma ou plasma)
Kaux, Jean-François ULg; Le Goff, Caroline ULg; Seidel, Laurence ULg et al

in Annales de Réadaptation et de Médecine Physique (2009, October), 52(Sup. 1), 109

Introduction : Depuis une vingtaine d’années, le développement des activités sportives s’accompagne d’une incidence accrue de diverses tendinopathies, souvent rebelles aux traitements conservateurs ... [more ▼]

Introduction : Depuis une vingtaine d’années, le développement des activités sportives s’accompagne d’une incidence accrue de diverses tendinopathies, souvent rebelles aux traitements conservateurs classiques (anti-inflammatoires non stéroïdiens, orthèses, kinésithérapie, infiltrations…). De nouvelles thérapeutiques, dont l’injection de concentrés plaquettaires (plasma riche en plaquettes ou PRP), sont actuellement en cours d’évaluation clinique. Objectifs : L’injection de PRP fait actuellement l’objet de recherche comme thérapeutique des tendinopathies chroniques. L’injection intra-tendineuse nécessite idéalement un volume minimal afin de diminuer la pression lors de l’injection et minimiser les douleurs, mais il doit également présenter une concentration plaquettaire élevée ; par ailleurs, la quantité de facteurs de croissance libérés pourrait être liée au système de préparation. Méthodes : Après avoir prélevés divers échantillons de sang veineux chez 5 patients, nous avons comparé 5 techniques de préparation du PRP : celle du Service d’Hématologie Biologique du CHU de Liège, le PRP Kit de Curasan®, les techniques Plateltex®, GPS®II et RegenLab®. Résultats : Les différentes techniques permettent d’obtenir des concentrations plaquettaires plus importantes que dans le sang avec des volumes variables (de 0,3 mL à 6 mL) et un nombre de globules rouges et globules blancs limité (sauf pour GPS® II). Le nombre de plaquettes/µL apparaît plus élevé avec la technique Plateltex® et obtient le plus petit volume à injecter. Les autres techniques permettent également d’obtenir de petits volumes sauf avec le GPS®II. Le nombre de plaquettes collectées dans le PRP apparaît donc plus élevé avec cette technique mais avec une concentration faible. Discussion – Conclusion : La technique décrite par Plateltex® permet de recueillir le PRP le plus concentré dans le volume le plus faible. [less ▲]

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See detailLe sociologue dans l'action collective face au risque
Mormont, Marc ULg

in Développement Durable et Territoires [= DDT] (2009)

Modern societies have organised complex systems to tackle with them. Environmental problems progressively reveal new risks that are said modern risks because they can be dealt with through usual systems ... [more ▼]

Modern societies have organised complex systems to tackle with them. Environmental problems progressively reveal new risks that are said modern risks because they can be dealt with through usual systems of risk assessment and management. If some authorities still deny these risks, it is important to observe new dynamics that are here described as capture of fear and that are giving strong power to those who are able to propose control systems. These systems can be destructive of many original and creative practices. Sociologist can not be confined in analysis of risk perception, he has to be involved in collective action that try to deal with risks by confronting different collectives and by reorganising them while preserving autonomy. [less ▲]

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See detailElectrostatic hierarchical co-assembly in aqueous solutions of two oppositevely charged double hydrophilic diblock copolymers
Voets, Ilja K.; de Keizer, Arie; Leermakers, Frans A. M. et al

in European Polymer Journal (2009), 45(10), 2913-2925

The formation of spherical micelles in aqueous solutions of poly(N-methyl-2-vinyl pyridinium iodide)-block-poly(ethylene oxide), P2MVP-b-PEO and poly(acrylic acid)-block-poly(vinyl alcohol), PAA-b-PVOH ... [more ▼]

The formation of spherical micelles in aqueous solutions of poly(N-methyl-2-vinyl pyridinium iodide)-block-poly(ethylene oxide), P2MVP-b-PEO and poly(acrylic acid)-block-poly(vinyl alcohol), PAA-b-PVOH has been investigated with light scattering-titrations, dynamic and static light scattering, and 1H 2D Nuclear Overhauser Effect Spectroscopy. Complex coacervate core micelles, also called PIC micelles, block ionomer complexes, and interpolyelectrolyte complexes, are formed in thermodynamic equilibrium under charge neutral conditions (pH 8, 1 mM NaNO3, T = 25 °C) through electrostatic interaction between the core-forming P2MVP and PAA blocks. 2D 1H NOESY NMR experiments show no cross-correlations between PEO and PVOH blocks, indicating their segregation in the micellar corona. Self-consistent field calculations support the conclusion that these C3Ms are likely to resemble a ‘patched micelle’; that is, micelles featuring a ‘spheres-on-sphere’ morphology. [less ▲]

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See detailIonosphere Modelling Based on the NeQuick Model and GNSS Data Ingestion
Bidaine, Benoît ULg; Warnant, René ULg

in Second International Colloquium - Scientific and Fundamental Aspects of the Galileo Programme (2009, October)

As for other GNSS, the ionospheric effect remains one of the main factors limiting Galileo accuracy. For single frequency users, this contribution to the error budget will be mitigated by a global ... [more ▼]

As for other GNSS, the ionospheric effect remains one of the main factors limiting Galileo accuracy. For single frequency users, this contribution to the error budget will be mitigated by a global algorithm based on the NeQuick model. This quick-run empirical model provides flexible solutions for combining ionospheric information obtained from various systems, from GNSS to ionosondes and topside sounders thanks to which NeQuick has been designed. Hence it constitutes an interesting simulation tool not only serving Galileo needs for mitigation of the ionospheric effect but also widening the use of new data available thanks to the future European system. NeQuick provides the electron density as a function of location, time and solar activity. Thanks to numerical integration, the total content in free electrons of the ionosphere (Total Electron Content, TEC) can be deduced as well as the ionospheric propagation delay depending linearly on TEC on satellite-to-receiver path. The model is particularly suited to be used within an optimization procedure called ingestion. In this framework, an “effective ionization level” Az plays the role of the solar activity input in order to fit a specific dataset. For Galileo single frequency operation, daily Az values will be computed from slant TEC measurements performed within the ground segment. In this study, we perform slant TEC ingestion for a dozen of locations around the world where both an ionosonde and a GPS receiver are installed. These collocated instruments allow us to compare measured and modelled vertical TEC in different ways showing for example global statistics or dependence towards latitude. We analyze such results for the year 2002 (high solar activity level) giving an interesting insight in the situation we could observe when Galileo reach its Full Operation Capability, during the next solar maximum. [less ▲]

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See detailUn centième Esperluète
Habrand, Tanguy ULg

Article for general public (2009)

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See detailChemical Imaging on Liver Steatosis Using Synchrotron Infrared and ToF-SIMS Microspectroscopies
Le Naour, François; Bralet, Marie-Pierre; Debois, Delphine ULg et al

in PLoS ONE (2009), 4(10), 7408

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See detailLeadership et genre : un regard croisé avec la psychanalyse
Cornet, Annie ULg; Cadalen, Sophie

Article for general public (2009)

La féminisation croissante des différents niveaux du management et l’augmentation du nombre de femmes occupant d e s p o s t e s à responsabilité ont s u s c i t é différentes recherches comparatives sur ... [more ▼]

La féminisation croissante des différents niveaux du management et l’augmentation du nombre de femmes occupant d e s p o s t e s à responsabilité ont s u s c i t é différentes recherches comparatives sur les styles de leadership mobilisés par les hommes et les femmes. Malgré les nombreuses études réalisées sur le sujet, on est très loin du consensus d’une part, sur l’existence ou non de différences dans le leadership féminin et masculin et d’autre part, sur les explications formulées pour avancer ces résultats. [less ▲]

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See detailLe PRP (Platelet-Rich Plasma) peut-il favoriser la régénération tendineuse ?
Kaux, Jean-François ULg; Drion, Pierre ULg; Pascon, Frédéric ULg et al

in Annales de Réadaptation et de Médecine Physique (2009, October), 52(Sup. 1), 109-110

Introduction : Certaines tendinopathies (l’épicondylite, la tendinopathie rotulienne supérieure ou encore la tendinopathie d’Achille) demeurent rebelles malgré un traitement « classique » bien conduit ... [more ▼]

Introduction : Certaines tendinopathies (l’épicondylite, la tendinopathie rotulienne supérieure ou encore la tendinopathie d’Achille) demeurent rebelles malgré un traitement « classique » bien conduit : repos, orthèse, AINS, électrothérapie, kinésithérapie, infiltrations de corticoïdes, ondes de choc... Certains travaux, essentiellement in vitro, soulignent les potentialités réparatrices des plaquettes qui présentent la capacité d’accélérer la cicatrisation de différents tissus : os, muscles et tendons. Objectifs : Le but de notre étude préliminaire est d’objectiver l’effet « accélérateur » sur la réparation tendineuse suite à l’emploi d’injection de plasma enrichi en plaquettes (platelet-rich plasma ou PRP) car cette technique pourrait représenter une thérapeutique d’avenir en médecine physique et en traumatologie du sport. Méthodes : Nous avons sectionné et réalisé un défect de 5mm dans le tendon d’Achille de rats (N = 12). Quatre rats ont bénéficié d’une injection in loco de PRP et remis en liberté comme les autres dans leur cage. Trois rats (2 sans PRP et 1 avec PRP) sont euthanasiés à J5, J10, J20 et J30 et le tendon d’Achille en cours de régénération est disséqué et prélevé. Une étude biomécanique de traction jusqu’à rupture est réalisé à l’aide de « Cryo-jaw ». Résultats : L’analyse des résultats montre que la force développée pour obtenir la rupture tendineuse doit être plus importante pour les tendons ayant bénéficié d’une injection de PRP et ce dès J5. Discussion – Conclusion : Cette série préliminaire permet de montrer que les injections de PRP permettent une accélération de la cicatrisation tendineuse et une augmentation des valeurs de résistances à la traction. Une étude avec un plus grand nombre de sujets est en cours. [less ▲]

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See detailCombining Color, Depth, and Motion for Video Segmentation
Leens, Jérôme ULg; Pierard, Sébastien ULg; Barnich, Olivier et al

in Computer Vision Systems (2009)

This paper presents an innovative method to interpret the content of a video scene using a depth camera. Cameras that provide distance instead of color information are part of a promising young technology ... [more ▼]

This paper presents an innovative method to interpret the content of a video scene using a depth camera. Cameras that provide distance instead of color information are part of a promising young technology but they come with many diff culties: noisy signals, small resolution, and ambiguities, to cite a few. By taking advantage of the robustness to noise of a recent background subtraction algorithm, our method is able to extract useful information from the depth signals. We further enhance the robustness of the algorithm by combining this information with that of an RGB camera. In our experiments, we demonstrate this increased robustness and conclude by showing a practical example of an immersive application taking advantage of our algorithm. [less ▲]

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See detailImproved Forwarding Architecture and Resource Management for Multi-Core Software Routers
Egi, Norbert; Greenhalgh, Adam; Handley, Mark et al

in NPC 2009 Proceedings (2009, October)

Recent technological advances in commodity server architectures, with multiple multi-core CPUs, integrated memory controllers, high-speed interconnects and enhanced network interface cards, provide ... [more ▼]

Recent technological advances in commodity server architectures, with multiple multi-core CPUs, integrated memory controllers, high-speed interconnects and enhanced network interface cards, provide substantial computational capacity and thus an attractive platform for packet forwarding. However, to exploit this available capacity, we need a suitable software platform that allows effective parallel packet processing and resource management. In this paper, we at first introduce an improved forwarding architecture for software routers that enhances parallelism by exploiting hardware classification and multi-queue support, already available in recent commodity network interface cards. After evaluating the original scheduling algorithm of the widely-used Click modular router, we propose solutions for extending this scheduler for improved fairness, throughput and more precise resource management. To illustrate the potential benefits of our proposal, we implement and evaluate a few key elements of our overall design. [less ▲]

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See detailExtending Routers Utilisability and Life Cycle through Automated Configuration Management
Rodriguez, Francisco; Hoerdt, Mickael; Mathy, Laurent ULg

in IPOM '09 Proceedings (2009, October)

We present the design of a distributed router platform aimed at consolidating multiple hardware routers. The goal of the approach is twofold: firstly decouple the logical routing and forwarding ... [more ▼]

We present the design of a distributed router platform aimed at consolidating multiple hardware routers. The goal of the approach is twofold: firstly decouple the logical routing and forwarding functionality from the limitations of the hardware that runs it, through automated configuration management only; and secondly, give component routers a longer lease of life, as constituting parts of a larger router system. We focus on the logical intra-domain routing function provided by routers, and show the need for a centralized intra-domain route server. [less ▲]

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See detailL'évaluation fonctionnelle et musculaire de l'épaule pathologique
Forthomme, Bénédicte ULg

in Livre des résumés du 1er Congrès de la Société Scientifique de Kinésithérapie : "Les outils d'évaluation Peut-on encore les ignorer ?" (2009, October)

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See detailLa visio conférence pour combattre le cancer
Coucke, Philippe ULg

Article for general public (2009)

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