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See detailA near-infrared interferometric survey of debris disk stars. I. Probing the hot dust content around eps Eridani and tau Ceti with CHARA/FLUOR
Di Folco, Emmanuel; Absil, Olivier ULg; Augereau, J.-C. et al

in Astronomy and Astrophysics (2007), 475

Context: The quest for hot dust in the central region of debris disks requires high resolution and high dynamic range imaging. Near-infrared interferometry is a powerful means to directly detect faint ... [more ▼]

Context: The quest for hot dust in the central region of debris disks requires high resolution and high dynamic range imaging. Near-infrared interferometry is a powerful means to directly detect faint emission from hot grains. Aims: We probed the first 3 AU around tau Ceti and eps Eridani with the CHARA array (Mt Wilson, USA) in order to gauge the 2 mum excess flux emanating from possible hot dust grains in the debris disks and to also resolve the stellar photospheres. Methods: High precision visibility amplitude measurements were performed with the FLUOR single mode fiber instrument and telescope pairs on baselines ranging from 22 to 241 m of projected length. The short baseline observations allow us to disentangle the contribution of an extended structure from the photospheric emission, while the long baselines constrain the stellar diameter. Results: We have detected a resolved emission around tau Cet, corresponding to a spatially integrated, fractional excess flux of 0.98±0.21 × 10[SUP]-2[/SUP] with respect to the photospheric flux in the K'-band. Around eps Eri, our measurements can exclude a fractional excess of greater than 0.6× 10[SUP]-2[/SUP] (3sigma). We interpret the photometric excess around tau Cet as a possible signature of hot grains in the inner debris disk and demonstrate that a faint, physical or background, companion can be safely excluded. In addition, we measured both stellar angular diameters with an unprecedented accuracy: Theta_LD(tau Cet)= 2.015 ± 0.011 mas and Theta_LD(eps Eri)=2.126 ± 0.014 mas. [less ▲]

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See detailNear-infrared spectroscopy for analysis of oil content and fatty acid profile in Jatropha curcas L. flour
Terren, Marieke ULg; Lecler, B.; Baeten, V. et al

Poster (2013)

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See detailNear-intrared observations of the HE 0450-2958 system: discovery of a second active galactic nucleus?
Letawe, Géraldine ULg; Magain, Pierre ULg; Chantry, Virginie ULg et al

in Monthly Notices of the Royal Astronomical Society (2009), 396(1), 78-84

The quasi-stellar object (QSO) HE 0450−2958 was brought to the front scene by the non-detection of its host galaxy and strong upper limits on the latter's luminosity. The QSO is also a powerful infrared ... [more ▼]

The quasi-stellar object (QSO) HE 0450−2958 was brought to the front scene by the non-detection of its host galaxy and strong upper limits on the latter's luminosity. The QSO is also a powerful infrared emitter, in gravitational interaction with a strongly distorted ultraluminous infrared companion galaxy. We investigate the properties of the companion galaxy, through new near- and mid-infrared observations of the system obtained with Near Infrared Camera and Multi-Object Spectrometer (NICMOS) onboard Hubble Space Telescope, Infrared Spectrometer and Array Camera (ISAAC) and Very Large Telescope Imager and Spectrometer in the Infrared (VISIR) on the European Southern Observatory Very Large Telescope. The companion galaxy is found to harbour a point source revealed only in the infrared, in what appears as a hole or dark patch in the optical images. Various hypotheses on the nature of this point source are analysed and it is found that the only plausible one is that it is a strongly reddened active galactic nucleus hidden behind a thick dust cloud. The hypothesis that the QSO supermassive black hole might have been ejected from the companion galaxy in the course of a galactic collision involving three-body black holes interaction is also reviewed, on the basis of this new insight on a definitely complex system. [less ▲]

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See detailA Near-IR [Fe II] line imaging survey of supernova remnants in M33
Morel, Thierry ULg; Doyon, R.; St-Louis, N.

in Proceedings 232. WE-Heraeus Seminar (2000, December 01)

We report on the first near-IR [Fe II] line imaging survey of extragalactic SNRs. Observations of a sample of 42 objects drawn from an optically-selected catalogue of SNRs in M33 provide evidence for a ... [more ▼]

We report on the first near-IR [Fe II] line imaging survey of extragalactic SNRs. Observations of a sample of 42 objects drawn from an optically-selected catalogue of SNRs in M33 provide evidence for a wide range in the [Fe II]λ 1.644 micron luminosities. This can be understood as being primarily due to variations in the chemical abundances and density of the local ISM, although shock conditions may also play a significant role. We briefly discuss how these results may be used to better calibrate the supernova rate of star-forming galaxies. [less ▲]

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See detailThe near-IR counterpart to the high-mass X-ray binary X1908+075
Morel, Thierry ULg; Grosdidier, Y.

in The Astronomer's Telegram (2004), 291

<html> We report the near-IR identification of the likely counterpart to X1908+075, a highly-absorbed Galactic X-ray source recently suspected to belong to the rare class of OB supergiant-neutron star ... [more ▼]

<html> We report the near-IR identification of the likely counterpart to X1908+075, a highly-absorbed Galactic X-ray source recently suspected to belong to the rare class of OB supergiant-neutron star binary systems (Wen et al. 2000, ApJ, 532, 1119; Levine et al. 2004, ApJ, submitted, astro-ph/0404428). The <em>Einstein</em> and <em>HEAO 1</em> satellites have localized this X-ray source with an uncertainty of about 50''. [less ▲]

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See detailNear-surface Geophysical Imaging and Detection of Slow Active Faults
Nguyen, Frédéric ULg

Doctoral thesis (2005)

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See detailNear-to-Surface properties affecting bond strength in concrete repair
Courard, Luc ULg; Piotrowski, Tomasz; Garbacz, Andrzej

in Cement and Concrete Composites (2014), 46

One of the main processes for repairing concrete structures is patch repair. Efficiency and durability of a repaired system depends on the bond between concrete substrate and repair material. By ... [more ▼]

One of the main processes for repairing concrete structures is patch repair. Efficiency and durability of a repaired system depends on the bond between concrete substrate and repair material. By increasing the surface roughness, the surface treatment of concrete substrate can promote mechanical interlocking that is one of the basic mechanisms of adhesion. Nevertheless, some problems may arise from “co-lateral” effects of the treatment, especially due to the development of microcracks inside the substrate. In the presented paper, the effect of concrete substrate surface preparation has been characterized by roughness measurement, description of microcracking in the near-to-surface layer and a pull-off cohesion test. After repair, pull-off bond strength has been evaluated. It is concluded that selection of a suitable surface treatment technique should be preceded by the analysis of its aggressiveness in relation to the concrete substrate strength. A procedure for bond strength estimation using multiple regression approach, based on parameters describing surface quality really generated from various roughening techniques, is then proposed. [less ▲]

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See detailNearby Galaxies Atlas -- R. B. Tully et J. R. Fisher
Manfroid, Jean ULg

in Ciel et Terre (1988), 104

Not Available

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See detailNearby galaxies Catalog -- R. B. Tully
Manfroid, Jean ULg

in Ciel et Terre (1988), 104

Not Available

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See detailThe Nebula around the Luminous Blue Variable WRAY 15-751 as seen by Herschel
Vamvatira-Nakou, Chloi ULg; Hutsemekers, Damien ULg; Royer, P. et al

in Massive Stars: From alpha to Omega (2013, June 01)

To understand the evolution of massive stars it is crucial to study the nebulae associated to Luminous Blue Variables which can reveal the star mass-loss history. We obtained far-infrared Herschel PACS ... [more ▼]

To understand the evolution of massive stars it is crucial to study the nebulae associated to Luminous Blue Variables which can reveal the star mass-loss history. We obtained far-infrared Herschel PACS imaging and spectroscopic observations of the nebula associated with the Luminous Blue Variable star WRAY 15-751. These images revealed a second nebula, bigger and cooler, lying in an empty cavity that probably delineates the remnant of the O-star bubble formed when the star was on the Main Sequence. The dust mass and temperature were derived from the modeling of the far-infrared SED. The analysis of the emission line spectrum revealed that the main nebula consists of a region of photoionised gas surrounded by a thin photodissociation region. Both regions are mixed with dust. The calculated C, N, O abundances, together with the estimated mass-loss rate, show that the nebula was ejected from the star during a Red Supergiant phase. This is compatible with the latest evolutionary tracks for a ~40 Mo star with little rotation. [less ▲]

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See detailNebulae around R Coronae Borealis stars - Clues to their evolutionary status?
Pollacco, D. L.; Hill, P. W.; Houziaux, Léo ULg et al

in Monthly Notices of the Royal Astronomical Society (1991), 248

Imaging and spectroscopy are presented of the classical R CrB star UW Cen obtained when the star was in a deep minimum. These show the presence of a faint reflection nebula, the inner parts of which ... [more ▼]

Imaging and spectroscopy are presented of the classical R CrB star UW Cen obtained when the star was in a deep minimum. These show the presence of a faint reflection nebula, the inner parts of which display two sets of symmetrical 'jets' centered on the star. The possibilities of whether the nebular structure can be associated with last thermal pulse evolution, white dwarf merger, or the mechanism causing the characteristic R CrB minima are discussed. [less ▲]

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See detailThe nebular spectra of two slow novae, DQ Herculis and RT Serpentis.
Swings, Polydore ULg; Struve, Otto

in Astrophysical Journal (1940), 92

The spectrum of Nova Herculis has been measured in the region λλ 3200-6700, and many new lines have been identified. The character of the spectrum has not changed greatly since the observations by Adams ... [more ▼]

The spectrum of Nova Herculis has been measured in the region λλ 3200-6700, and many new lines have been identified. The character of the spectrum has not changed greatly since the observations by Adams and Joy in 1935-1936, but the increased separation between the two visual components of the Nova has now made it possible to observe separately the two spectra. The ionization seems to be identically the same in the two objects, but some differences in the structure of the lines was noticed. Spectra taken with the slit along the major axis of the elongated image show a marked depression between the two outside components of the emission lines, while at least the preceding component of the binary shows a fairly strong central component between the two outside components. The observations are sensitive to conditions of seeing, and it is not possible at this stage to unravel the true nature of the spectroscopic structure of the lines. The spectrum of Nova Serpentis, which had an outburst in 1909 and which is known to have developed abnormally slowly, was last described by Joy in 1931. Since that time the spectrum has undergone marked changes: the lines of [Fe III], which were strong in 1931, are very weak on our spectrogram. Instead, [Ne III], [Ne V], and [Fe VI] are strong, in addition to H, He I, He II, and [O III]. [less ▲]

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See detailNebulised salbutamol administered during sputum induction improves bronchoprotection in patients with asthma
Delvaux, Muriel ULg; Henket, Monique ULg; Lau, L. et al

in Thorax (2004), 59(2), 111-115

Background: Inhalation of hypertonic or even isotonic saline during sputum induction may cause bronchospasm in susceptible patients with asthma, despite premedication with 400 mug inhaled salbutamol ... [more ▼]

Background: Inhalation of hypertonic or even isotonic saline during sputum induction may cause bronchospasm in susceptible patients with asthma, despite premedication with 400 mug inhaled salbutamol delivered by pressurised metered dose inhaler (pMDI). The bronchoprotection afforded by additional inhaled salbutamol administered through the ultrasonic nebuliser during sputum induction was investigated. Methods: Twenty patients with moderate to severe asthma underwent sputum induction by inhaling saline 4.5% (or 0.9% if post-bronchodilation forced expiratory volume in 1 second (FEV1) <65% predicted) for 10 minutes according to two protocols given 1 week apart in random order. At visit A the patients received 400 mg salbutamol administered through a pMDI + spacer 20 minutes before induction while at visit B the premedication was supplemented by 1500 mg nebulised salbutamol inhaled throughout the induction procedure. Both the investigator and the patients were blind to the nebulised solution used. FEV1 was recorded during sputum induction at 1, 3, 5, and 10 minutes. Sputum cell counts and histamine, tryptase and albumin levels in the supernatants were determined. Results: The mean (SE) maximal reduction in FEV1 over the 10 minute period of sputum induction was 11.7 (2.8)% at visit A, which was significantly greater than at visit B (2.6 (1.2)%; mean difference 9% (95% CI 2.7 to 15.4), p < 0.01). Total and differential sputum cell counts as well as albumin, tryptase, and histamine levels did not differ between the two visits. Conclusion: The addition of inhaled salbutamol through an ultrasonic nebuliser markedly improves bronchoprotection against saline induced bronchoconstriction in patients with moderate to severe asthma undergoing sputum induction without affecting cell counts and inflammatory markers. [less ▲]

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See detailNebulized Anti-IL-13 Monoclonal Antibody Fab' Fragment Reduces Allergen-Induced Asthma
Hacha, Jonathan ULg; Tomlinson, K; Maertens, Ludovic ULg et al

in American Journal of Respiratory Cell and Molecular Biology (2012), sous presse

Rationale: Interleukin-13 (IL-13) is a prototypic Th2 cytokine and a central mediator of the complex cascade of events leading to asthmatic phenotype. Indeed, IL-13 plays key roles in IgE synthesis ... [more ▼]

Rationale: Interleukin-13 (IL-13) is a prototypic Th2 cytokine and a central mediator of the complex cascade of events leading to asthmatic phenotype. Indeed, IL-13 plays key roles in IgE synthesis, bronchial hyperresponsiveness, mucus hypersecretion, subepithelial fibrosis and eosinophil infiltration. Objectives: We assessed the potential efficacy of inhaled anti-IL-13 monoclonal antibody Fab' fragment on allergen-induced airway inflammation, hyperresponsiveness and remodeling in an experimental model of allergic asthma. Anti-IL-13 Fab' was administered to mice as a liquid aerosol generated by inExpose® inhalation system in a tower allowing a nose-only exposure. Methods: BALB/c mice were treated by PBS, anti-IL-13 Fab' or A33 Fab' fragment and subjected to ovalbumin (OVA) exposure for 1 and 5 weeks (short term (ST) and long term (LT) protocols). Measurements and Main Results: Our data demonstrate a significant anti-asthma effect following nebulization of anti-IL-13 Fab' in a model of asthma driven by allergen exposure as compared to saline and non-immune Fab fragments. In short and long terms protocols, administration of the anti-IL-13 Fab' by inhalation significantly decreased bronchial responsiveness to methacholine, BALF eosinophilia, inflammatory cell infiltration in lung tissue, and many features of airway remodeling. Levels of pro-inflammatory mediators and matrix metalloprotease levels were significantly lower in lung parenchyma of mice treated with anti-IL-13 Fab'. Conclusions: These data demonstrate that an inhaled anti-IL-13 Fab' significantly reduces airway inflammation, hyperresponsiveness and remodeling. Specific neutralization of IL-13 in the lungs using an inhaled anti-IL-13 Fab' could represent a novel and effective therapy for the treatment of asthma. [less ▲]

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See detailUne nécessaire formation des enseignants-chercheurs ?
Poumay, Marianne ULg

Scientific conference (2011, March 21)

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See detailLa nécessité d'un inventaire du patrimoine culturel immatériel
Lempereur, Françoise ULg

in Géants d'ici et d'ailleurs (2012, January), (6-7), 24-30

Destinée essentiellement aux institutions et groupements qui ont en charge la sauvegarde du patrimoine culturel immatériel, cette présentation rapide justifie l'inventorisation de ce patrimoine, en ... [more ▼]

Destinée essentiellement aux institutions et groupements qui ont en charge la sauvegarde du patrimoine culturel immatériel, cette présentation rapide justifie l'inventorisation de ce patrimoine, en définit les responsabilités et propose une méthodologie de collectage et de mise à disposition publique des contenus [less ▲]

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See detailNécessité de nouveaux critères de remboursement pour traiter l'ostéoporose en Belgique
Bruyère, Olivier ULg; Bergmann, Pierre; Body, Jean-Jacques et al

in Ortho-Rhumato (2012), 10(5), 3

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