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See detailAn upper limit for the water outgassing rate of the main-belt comet 176P/LINEAR observed with Herschel/HIFI
de Val-Borro, M.; Rezac, L.; Hartogh, P. et al

in Astronomy and Astrophysics (2012), 546

176P/LINEAR is a member of the new cometary class known as main-belt comets (MBCs). It displayed cometary activity shortly during its 2005 perihelion passage, which may be driven by the sublimation of ... [more ▼]

176P/LINEAR is a member of the new cometary class known as main-belt comets (MBCs). It displayed cometary activity shortly during its 2005 perihelion passage, which may be driven by the sublimation of subsurface ices. We have therefore searched for emission of the H[SUB]2[/SUB]O 1[SUB]10[/SUB]-1[SUB]01[/SUB] ground state rotational line at 557 GHz toward 176P/LINEAR with the Heterodyne Instrument for the Far Infrared (HIFI) onboard the Herschel Space Observatory on UT 8.78 August 2011, about 40 days after its most recent perihelion passage, when the object was at a heliocentric distance of 2.58 AU. No H[SUB]2[/SUB]O line emission was detected in our observations, from which we derive sensitive 3-σ upper limits for the water production rate and column density of <4 × 10[SUP]25[/SUP] mol s[SUP]-1[/SUP] and of <3 × 10[SUP]10[/SUP] cm[SUP]-2[/SUP], respectively. From the peak brightness measured during the object's active period in 2005, this upper limit is lower than predicted by the relation between production rates and visual magnitudes observed for a sample of comets at this heliocentric distance. Thus, 176P/LINEAR was most likely less active at the time of our observation than during its previous perihelion passage. The retrieved upper limit is lower than most values derived for the H[SUB]2[/SUB]O production rate from the spectroscopic search for CN emission in MBCs. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA. [less ▲]

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See detailBrèves considérations relatives à l'intégration européenne : l'Union européenne et le Conseil de l'Europe
Behrendt, Christian ULg; Bouhon, Frédéric ULg

Learning material (2012)

Cette brève contribution dresse un portrait général des deux moteurs de l'intégration européenne : l'Union européenne et le Conseil de l'Europe.

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See detailWASP-36b: A new transiting planet around a metal-poor G-dwarf, and an analysis of correlated noise in transit light curves
Smith, A. M. S.; Anderson, D. R.; Collier Cameron, A. et al

in Astronomical Journal (The) (2012), 143(4), 10

We report the discovery, from WASP and CORALIE, of a transiting exoplanet in a 1.54-d orbit. The host star, WASP-36, is a magnitude 12.7, metal-poor G2 dwarf (Teff = 5881 +/- 137 K), with [Fe/H] = -0.31 ... [more ▼]

We report the discovery, from WASP and CORALIE, of a transiting exoplanet in a 1.54-d orbit. The host star, WASP-36, is a magnitude 12.7, metal-poor G2 dwarf (Teff = 5881 +/- 137 K), with [Fe/H] = -0.31 +/- 0.12. We determine the planet to have mass and radius respectively 2.27 +/- 0.07 and 1.27 +/- 0.03 times that of Jupiter. We have eight partial or complete transit light curves, from four different observatories, which allows us to investigate the extent to which red noise in follow-up light curves affects the fitted system parameters. We find that the solutions obtained by analysing each of these light curves independently are consistent with our global fit to all the data, despite the apparent presence of correlated noise in at least two of the light curves. [less ▲]

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See detailStellar Occultations by Large TNOs on 2012: The February 3rd by (208996) 2003 AZ84, and the February 17th by (50000) Quaoar
Braga Ribas, Felipe; Sicardy, B.; Ortiz, J. L. et al

in AAS/Division for Planetary Sciences Meeting Abstracts (2012, October 01)

On February 2012, two stellar occultation's by large Trans-neptunian Objects (TNO's) were observed by our group. On the 3rd, an event by (208996) 2003 AZ84 was recorded from Mont Abu Observatory and IUCAA ... [more ▼]

On February 2012, two stellar occultation's by large Trans-neptunian Objects (TNO's) were observed by our group. On the 3rd, an event by (208996) 2003 AZ84 was recorded from Mont Abu Observatory and IUCAA Girawali Observatory in India and from Weizmann Observatory in Israel. On the 17th, a stellar occultation by (50000) Quaoar was observed from south France and Switzerland. Both occultations are the second observed by our group for each object, and will be used to improve the results obtained on the previous events. The occultation by 2003 AZ84 is the first multi-chord event recorded for this object. From the single chord event on January 8th 2011, Braga-Ribas et al. 2011 obtained a lower limit of 573 +/- 21 km. From the 2012 occultation the longest chord has a size of 662 +/- 50 km. The other chords will permit to determine the size and shape of the TNO, and derive other physical parameters, such as the geometric albedo. The Quaoar occultation was observed from south of France (Observatoire de la Côte d'Azur, TAROT telescope and Valensole) and from Gnosca, Switzerland. Unfortunately, all three sites in France are almost at the same Quaoar's latitude, so in practice, we have two chords that can be used to fit Quaoar's limb. The resulting fit will be compared with the results obtained by Braga-Ribas et al. 2011. Braga-Ribas F., Sicardy B., et al. 2011, EPSC-DPS2011, 1060.Ribas F., Sicardy B., et al. 2011, EPSC-DPS2011, 1060. [less ▲]

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See detailSeven transiting hot-Jupiters from WASP-South, Euler and TRAPPIST: WASP-47b, WASP-55b, WASP-61b, WASP-62b, WASP-63b, WASP-66b & WASP-67b
Hellier, Coel; Anderson, D R; Collier Cameron, A et al

in Monthly Notices of the Royal Astronomical Society (2012), 426

We present seven new transiting hot Jupiters from the WASP-South survey. The planets are all typical hot Jupiters orbiting stars from F4 to K0 with magnitudes of V = 10.3 to 12.5. The orbital periods are ... [more ▼]

We present seven new transiting hot Jupiters from the WASP-South survey. The planets are all typical hot Jupiters orbiting stars from F4 to K0 with magnitudes of V = 10.3 to 12.5. The orbital periods are all in the range 3.9--4.6 d, the planetary masses range from 0.4--2.3 Mjup and the radii from 1.1--1.4 Mjup. In line with known hot Jupiters, the planetary densities range from Jupiter-like to inflated (rho = 0.13--1.07 rho_jup). We use the increasing numbers of known hot Jupiters to investigate the distribution of their orbital periods and the 3--4-d "pile-up". [less ▲]

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See detailCharon's Size And Orbit From Double Stellar Occultations
Sicardy, Bruno; Braga-Ribas, F.; Widemann, T. et al

in AAS/Division for Planetary Sciences Meeting Abstracts (2012, October 01)

Stellar occultations of a same star by both Pluto and Charon (double events) yield instantaneous relative positions of the two bodies projected in the plane of the sky, at 10km-level accuracy. Assuming a ... [more ▼]

Stellar occultations of a same star by both Pluto and Charon (double events) yield instantaneous relative positions of the two bodies projected in the plane of the sky, at 10km-level accuracy. Assuming a given pole orientation for Charon's orbit, double events provide the satellite plutocentric distance r at a given orbital longitude L (counted from the ascending node on J2000 mean equator), and finally, constraints on its orbit. A double event observed on 22 June 2008 provides r=19,564+/-14 km at L=153.483+/-0.071 deg. (Sicardy et al. 2011), while another double event observed on 4 June 2011 yields: r=19,586+/-15 km at L = 343.211+/-0.072 deg. (all error bars at 1-sigma level). These two positions are consistent with a circular orbit for Charon, with a semi-major axis of a=19,575+\-10 km. This can be compared to the circular orbit found by Buie et al. (2012), based on Hubble Space Telescope data, with a=19,573+/-2 km. The 4 June 2011 stellar occultation provides 3 chords across Charon, from which a radius of Rc= 602.4+/-1.6 km is derived. This value can be compared to that obtained from the 11 July 2005 occultation: Rc= 606.0+/-1.5 km (Person et al. 2006) and Rc= 603.6+/-1.4 km (Sicardy et al. 2006). A third double event, observed on 23 June 2011 is under ongoing analysis, and will be presented. Buie et al. (2012), AJ 144, 15-34 (2012) Person et al, AJ 132, 1575-1580 (2006) Sicardy et al., Nature 439, 52-54 (2006) Sicardy et al., AJ 141, 67-83 (2011) B.S. thanks ANR "Beyond Neptune II". L.A.Y. acknowledges support by NASA, New Horizons and National Geographic grants. We thank B. Barnard, M.J. Brucker, J. Daily, C. Erikson, W. Fukunaga, C. Harlinten, C. Livermore, C. Nance, J.R. Regester, L. Salas, P. Tamblyn, R. Westhoff for help in the observations. [less ▲]

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See detailThe nature of the high Galactic latitude O-star HD 93521: new results from X-ray and optical spectroscopy
Rauw, Grégor ULg; Morel, Thierry ULg; Palate, Matthieu ULg

in Astronomy and Astrophysics (2012), 546

Context. Owing to its unusual location and its isolation, the nature of the high Galactic latitude O9.5 Vp object HD 93521 is still uncertain. <BR /> Aims: We have collected X-ray and optical observations ... [more ▼]

Context. Owing to its unusual location and its isolation, the nature of the high Galactic latitude O9.5 Vp object HD 93521 is still uncertain. <BR /> Aims: We have collected X-ray and optical observations to characterize the star and its surroundings. <BR /> Methods: X-ray images and spectra are analysed to search for traces of a recent star formation event around HD 93521 and to search for the signature of a possible compact companion. Optical echelle spectra are analysed with plane-parallel model atmosphere codes, assuming either a spherical star or a gravity darkened rotationally flattened star, to infer the effective temperature and surface gravity, and to derive the He, C, N and O abundances of HD 93521. <BR /> Results: The X-ray images reveal no traces of a population of young low-mass stars coeval with HD 93521. The X-ray spectrum of HD 93521 is consistent with a normal late O-type star although with subsolar metallicity. No trace of a compact companion is found in the X-ray data. In the optical spectrum, He and N are found to be overabundant, in line with the effect of rotational mixing in this very fast rotator, whilst C and O are subsolar. A critical comparison with the properties of subdwarf OB stars, indicates that, despite some apparent similarities, HD 93521 does not belong to this category. <BR /> Conclusions: Despite some ambiguities on the runaway status of the star, the most likely explanation is that HD 93521 is a Population I massive O-type star that was ejected from the Galactic plane either through dynamical interactions or a result of a supernova event in a binary system. Based on observations collected at the Observatoire de Haute Provence (France) and with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA member states and the USA (NASA).Hα images are only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via <A href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/546/A77">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/546/A77</A> [less ▲]

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See detailISU team project: Space debris mitigation and removal
Adriaensen, Maarten; Rüdiger, Jehn; Gini, Andrea et al

in Proceedings of the 63rd International Astronautical Congress, IAC (2012, October 01)

The space debris problem has been studied for over 30 years. However, we are still far away from implementing an effective approach to solve the problem. A solution will require several aspects to be ... [more ▼]

The space debris problem has been studied for over 30 years. However, we are still far away from implementing an effective approach to solve the problem. A solution will require several aspects to be addressed: technological development, political and legal frameworks, financial and business aspects, and strategies of raising awareness in the general public and political decision makers. Most spacefaring nations appear to be adopting a 'wait-and-see' approach to the problem. All these aspects are investigated with a multidisciplinary approach. The paper addresses debris mitigation and removal from a technical perspective. Then, political, legal, economic and organisational aspects are described, as well as the awareness issue of the problem. Finally a set of recommendations is offered in the frame of a roadmap comprising short-term (2013-2016), mid-term (2016-2020) and long-term (2020-2053). The recommendations will show how to build-up the technological knowledge, and the economic and legal framework to enable, starting in 2020, a sustainable use of space thanks to the full adherence of mitigation guidelines and the active removal of 10 extra-large debris per year managed by a dedicated international organisation supported by adequate funding. This paper is based on the findings of the International Space University Space Studies Programme (ISU SSP) Team Project: Space Debris Mitigation and Removal. The findings are the result of the research of a team consisting of about 40 professionals and students active in the field of space at the ISU SSP. The Programme was organised by ISU in cooperation with Florida Institute of Technology and NASA Kennedy Space Center. [less ▲]

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See detailEvidence for a partial epithelial-mesenchymal transition in rat auditory organ development
Johnen, Nicolas ULg; Francart, Marie-Emilie; Thelen, Nicolas ULg et al

Poster (2012, October 01)

An epithelial-mesenchymal transition is a biological process that allows a polarized epithelial cell to undergo multiple biochemical changes that enable it to assume a mesenchymal cell phenotype. During ... [more ▼]

An epithelial-mesenchymal transition is a biological process that allows a polarized epithelial cell to undergo multiple biochemical changes that enable it to assume a mesenchymal cell phenotype. During this process, epithelial cells loosen cell-cell adhesion, module their polarity and rearrange their cytoskeleton: intermediate filaments typically switch from cytokeratin to vimentin. They also enhance their motility capacity. The epithelial-mesenchymal transition plays key roles in the formation of the body plan and in the differentiation of multiple tissues and organs but it is also involved in tissue repair, tissue homeostasis, fibrosis, and carcinoma progression. Until now, epithelial-mesenchymal transition has been rarely mentioned in the inner ear organogenesis. In chick, epithelial-mesenchymal transition has been reported as a possible mechanism of semicircular canal morphogenesis. More recently, an in vitro study has also indicated that sensory epithelial cells from mouse utricle can undergo an epithelial-mesenchymal transition to become cells expressing features of prosensory cells. By contrast, epithelial-mesenchymal transition has never been observed during auditory organ morphogenesis. The auditory organ, the organ of Corti, is a highly specialized structure composed by specific cellular types. The sensory cells are characterized by stereocilia at their apex and are necessary for the sound perception. Theses cells are supported by supporting cells. Based on their morphology and physiology, at least four types of supporting cells can be identified in the organ of Corti: inner and outer pillar cells, phalangeal cell and Deiter’s cells. The inner pillar cells and outer pillar cells combine to form the tunnel of Corti, a fluid filled triangular space that separates the single row of inner hair cells from the first row of outer hair cells. The Nuel spaces are another interval in the organ of Corti that is situated between the outer pillar cells and the different rows of outer hair cells and Deiters cells. To determine whether an epithelial-mesenchymal transition may play a role in the morphogenesis of the auditory organ, we studied the spatial localization of several epithelial-mesenchymal transition markers, the cell-cell adhesion molecules and intermediate filament cytoskeletal proteins, in epithelium of the dorsal cochlea during development of the rat organ of Corti from 18th embryonic day until 25th postnatal day. We examined by confocal microscopy immunolabelings on cryosections of whole cochleae with antibodies anti-cytokeratins as well as with antibodies anti-vimentin, anti-E-cadherin and anti-beta-catenin.Our results showed a partial loss of E-cadherin and beta-catenin between supporting cells at P8 and P12, respectively, and a temporary appearance of vimentin in pillar cells and Deiters between P8 and P10. Our results show a local loss of adhesion between supporting cells of the OC from P8, an increase expression of cytokeratins in supporting cells around P10 and a temporary appearance of vimentin in supporting cells at P8-10. These observations suggest that a partial epithelial-mesenchymal transition might be involved in the remodeling of the Corti organ during the postnatal stages of development in rat. [less ▲]

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See detailUsage, Usability, and Utility of 3D City models
Leduc, Thomas; Moreau, Guillaume; Billen, Roland ULg

Book published by edp Sciences (2012)

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See detailMolecular analysis of the interfacial and membrane-interacting properties of D-xylose-based bolaforms
Nasir, Mehmet Nail ULg; Legrand, Vincent; Gatard, Sylvain et al

Poster (2012, October)

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See detailDosimetry for 6-[18F]Fluoro-L-DOPA in Humans Based on Biodistribution in Mice
Bretin, Florian ULg; Warnock, Geoffrey ULg; Bahri, Mohamed Ali ULg et al

Poster (2012, October)

Aim. The objective of this work was to estimate human dosimetry for 6-[18F]Fluoro-L-DOPA (F-DOPA) from biodistribution in mice, obtained from organ harvesting at different time points and from a hybrid ... [more ▼]

Aim. The objective of this work was to estimate human dosimetry for 6-[18F]Fluoro-L-DOPA (F-DOPA) from biodistribution in mice, obtained from organ harvesting at different time points and from a hybrid method combining dynamic PET followed by organ harvesting. Materials and methods. The tissue distribution of F-DOPA over time was determined in isoflurane-anaesthetized mice. Radioassay was performed on harvested organs at 2, 5, 10, 30, 60 and 120 minutes post administration (n = 5 at each time point). Dynamic PET images were acquired in list-mode with a Siemens FOCUS 120 microPET for 120 minutes after injection and followed by radioassay of harvested organs (n = 4). List-mode data were histogrammed in 6*5s, 6*10s, 3*20s, 5*30s, 5*60s, 8*150s, 6*300s, 6*600s 3D sinograms. Final images were obtained using filtered backprojection with correction for all physical effects except for scatter. Attenuation correction resulted from a pre-injection transmission scan with a cobalt-57 point source. Organs were manually delineated. The organ time-activity-curves (TACs) from both methods were extrapolated from a simulated 35 g standard mouse to a 70 kg standard male human using a technique based on organ to bodyweight ratios. A bladder voiding scenario was used to simulate excretion every 2 h. The absorbed doses in major human organs were calculated using the extrapolated TACs with the commercially available software OLINDA/EXM (Version 1.1). Results. The extrapolated organ activity curves obtained using the harvesting and imaging methods showed a high correlation (r = 0.94 ± 0.05, p < 0.001). However, TACs from PET alone under- or overestimated the activity in individual organs in contrast to TACs obtained using the cross-calibration of the PET data with the activity in post-scan dissected organs. Those organs in the excretion pathways, comprising bladder wall, kidneys and liver, received the highest organ doses. The total body absorbed dose was 0.0118 mGy/MBq for both the imaging based and harvesting based methods. The effective dose was 0.0193 mSv/MBq for the hybrid imaging-harvesting technique and 0.0189 mSv/MBq for the pure harvesting technique. Conclusion. The doses obtained agreed well with the few results available in the literature. The hybrid technique combining dynamic PET scanning followed by organ harvesting appeared to be a good alternative to the gold standard ex vivo radioassay method. It is much faster and minimizes the effect of some weakness of the pure imaging technique, such as partial volume effect. [less ▲]

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See detailA comparative study of sexual product quality in F1 hybrids of the bream Abramis brama X the silver bream Blicca bjoerkna
Nzau Matondo, Billy ULg; Ovidio, Michaël ULg; Philippart, Jean-Claude ULg et al

in Fisheries Science (2012), 78

The gonadosomatic index at spawning, absolute fecundity, and egg size for the female sexual products as well as the density and consistency of semen for the male sexual products were examined in cultured ... [more ▼]

The gonadosomatic index at spawning, absolute fecundity, and egg size for the female sexual products as well as the density and consistency of semen for the male sexual products were examined in cultured Abramis brama 9 Blicca bjoerkna F1 hybrids and compared with the parental species at their first sexual maturity. Females ovulated under environmental conditions, and their eggs were weighed, counted and measured. Semen of males was macroscopically examined and spermatozoa counted using a hemocytometer. Results revealed that hybridization affected the quality of female and male gametes but with an overlap between hybrids and parents. The gonadosomatic index and fecundity were significantly lower than those of parental species. Egg sizes in hybrids showed a parental effect but to the benefit of hybrids. Semen of hybrids was more diluted which was classified into two groups: the white semen overlapping slightly with parents and the aqueous without any overlap with parents. Overlapped areas between hybrids and parents in term of quality of sexual products could translate that females and males of these hybrids have the biological capacity to produce high quality gametes and thus, a greater chance to produce F2 and backcross generations in rivers. [less ▲]

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See detailMaths & Manips pour le primaire. Favoriser l'apprentissage des grandeurs par des manipulations
Guissard, Marie-France; Henry, Valérie ULg; Vansimpsen, Sylvie et al

Conference (2012, October)

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See detailLes spécificités de la gestion d'une maison de luxe : vers une modélisation atemporelle de la performance
Riguelle, France ULg; Van Caillie, Didier ULg

in AIREPME (Ed.) Actes du CIFEPME 2012 (2012, October)

Le but ultime de la présente recherche est de modéliser la performance des maisons de luxe de manière transversale (nous décidons de ne pas privilégier l’approche marketing comme une grande partie de la ... [more ▼]

Le but ultime de la présente recherche est de modéliser la performance des maisons de luxe de manière transversale (nous décidons de ne pas privilégier l’approche marketing comme une grande partie de la littérature dédiée à la gestion des métiers du luxe) et atemporelle. Nous proposons d’organiser, au travers du Prime de la Performance (Neely, Adams et Kennerley, 2002), les FCS dont la mise en œuvre permet d’atteindre la performance globale. Cette recherche constitue donc un premier pas vers une modélisation de la performance de la maison de luxe. [less ▲]

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See detailOptimization of POP analysis in small sample amounts.
L'Homme, Benjamin ULg; Focant, Jean-François ULg

Conference (2012, October)

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See detailL’affaire du voile en Belgique : la vision médiatique de la femme arabo-musulmane réduite à son voile
Luceno Moreno, Marta ULg

Conference (2012, October)

Cela fait maintenant plus de 20 ans que l’affaire du voile a éclaté en Belgique pour la première fois, contaminée par le débat public ouvert en France après l’exclusion du lycée de Creil de trois jeunes ... [more ▼]

Cela fait maintenant plus de 20 ans que l’affaire du voile a éclaté en Belgique pour la première fois, contaminée par le débat public ouvert en France après l’exclusion du lycée de Creil de trois jeunes qui portaient le hijab. Comme en France, depuis 1989 la question du hijab apparaît et disparaît de la scène médiatique belge par intermittence. À la différence de la France, qui en 2004 se penche sur la question afin de trouver une solution juridique fermant définitivement la controverse, la question du hijab à l’école va rester perpétuellement dans le débat belge par manque de solutions politiques. Toutefois, si dans un premier temps la question du hijab se posait uniquement dans les écoles, à partir de 2004 le débat s'élargit et concerne peu à peu les administrations publiques, les salles de justice ou le Parlement, avant d’occuper la totalité de l’espace public avec la question de la burqa. [less ▲]

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See detailIntroduction générale : les organisations régionales dans les relations internationales
Santander, Sébastian ULg

in Santander, Sébastian (Ed.) Relations internationales et régionalisme. Entre dynamiques internes et projections mondiales (2012)

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