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See detailDetection of the lensing galaxy for the double QSO HE 1104-1805
Remy, M.; Claeskens, Jean-François ULg; Surdej, Jean ULg et al

in New Astronomy (1998), 3

High angular resolution ground-based direct imaging (V, R, I_c) of the double QSO HE 1104-1805 has been obtained with the NOT and NTT telescopes. Analysis of these data led to the first detection of the ... [more ▼]

High angular resolution ground-based direct imaging (V, R, I_c) of the double QSO HE 1104-1805 has been obtained with the NOT and NTT telescopes. Analysis of these data led to the first detection of the lensing galaxy. Direct imaging of HE 1104-1805 has subsequently been carried out with the Planetary Camera (WFPC2) through the F555W (nearly Johnson V) and F814W (nearly Kron-Cousins I_c) filters onboard HST. These images confirm the presence of the deflector between the two lensed quasar components (A & B). Direct imaging of this system in the near infrared (IR) at 2.2 mu-m (K'), with IRAC-2b at the Cassegrain focus of the ESO/MPI 2.2 m telescope, indicates that the additional component is indeed a very red extended object with magnitude K ~= 16.5. We present deconvolutions of the HST and IR images using the 2-channel PLUCY method. From the HST observations, we also report very accurate relative positions and brightnesses of the QSO components. By comparison between the ground-based and the HST observations, from February-March 1994 to November 1995, we possibly detect the fading of component A by ~ 0.3 magnitudes in the optical and a corresponding fading of B by about half this value. The observed monotonic decrease of the magnitude difference between B and A as a function of wavelength is consistent with a partial amplification of the A component by microlensing. Evolutionary models for galaxies show that, in order to produce the observed colour indices V - I_c > 2 and 4 < I_c - K < 4.5, the galaxy is likely to be of elliptical type with a redshift 0.95 < z < 1.4. This range is consistent with the redshift z=1.32 measured from the absorption lines of metallic species in the spectra of the quasar components. However, other values for the redshift of the lens inside this range cannot be excluded. This galaxy would presently be among the most distant known gravitational lenses. Several theoretical models are found to fit the observations. The simplest one is a singular isothermal sphere (SIS) lens immersed in an external shear with gamma=0.123. The derived mass-to-light ratio (11 h_50 M_Sun/L_Sun) for the galaxy is large but does not imply an excess of dark matter with respect to other well known lensing galaxies. [less ▲]

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See detailDetection of the lensing galaxy in HE 1104-1805
Courbin, F.; Lidman, C.; Magain, Pierre ULg

in Astronomy and Astrophysics (1998), 330

We report on deep IR imaging of the double quasar HE 1104-1805. A new image deconvolution technique has been applied to the data in order to optimally combine the numerous frames obtained. The resulting J ... [more ▼]

We report on deep IR imaging of the double quasar HE 1104-1805. A new image deconvolution technique has been applied to the data in order to optimally combine the numerous frames obtained. The resulting J and K' images allow us to detect and study the lensing galaxy between the two lensed QSO images. The near infrared images not only confirm the lensed nature of this double quasar, but also support the previous redshift estimate of z=1.66 for the lensing galaxy. No obvious overdensity of galaxies is detected in the immediate region surrounding the lens, down to limiting magnitudes of J=22 and K=20. The geometry of the system, together with the time delays expected for this lensed quasar, make HE 1104-1805 a remarkable target for future photometric monitoring programs, for the study of microlensing and for the determination of the cosmological parameters in the IR and optical domains. Based on observations obtained at ESO, La Silla, Chile [less ▲]

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See detailDetection of the Photoactive Protochlorophyllide-Protein Complex in the Light During the Greening of Barley
Franck, Fabrice ULg; Strzalka, K.

in FEBS Letters (1992), 309(1), 73-7

A photoactive protochlorophyllide-protein complex with absorbance and fluorescence maxima at 648 and 653 nm was detected in greening barley leaves without any re-darkening. The variations of the ... [more ▼]

A photoactive protochlorophyllide-protein complex with absorbance and fluorescence maxima at 648 and 653 nm was detected in greening barley leaves without any re-darkening. The variations of the amplitudes of the absorbance and the fluorescence of the photoactive protochlorophyllide with greening time at two different light intensities indicate a close relationship between the rate of chlorophyll synthesis and the amount of the complex during the first hours. The chlorophyllide resulting from photoreduction during greening has an absorbance maximum at 684 nm, which shifts towards a shorter wavelength within a few seconds, indicating rapid liberation of the pigment from the enzyme. We conclude that chlorophyll accumulation proceeds through continuous regeneration and phototransformation of the photoactive complex. [less ▲]

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See detailDetection of Thermal Emission from a Super-Earth
Demory, Brice*-Olivier; Gillon, Michaël ULg; Seager, Sara et al

in Astrophysical Journal Letters (2012), 751(2), 28

We report on the detection of infrared light from the super-Earth 55 Cnc e, based on four occultations obtained with Warm Spitzer at 4.5 microns. Our data analysis consists of a two-part process. In a ... [more ▼]

We report on the detection of infrared light from the super-Earth 55 Cnc e, based on four occultations obtained with Warm Spitzer at 4.5 microns. Our data analysis consists of a two-part process. In a first step, we perform individual analyses of each dataset and compare several baseline models to optimally account for the systematics affecting each lightcurve. We apply independent photometric correction techniques, including polynomial detrending and pixel-mapping, that yield consistent results at the 1-sigma level. In a second step, we perform a global MCMC analysis including all four datasets, that yields an occultation depth of 131+-28ppm, translating to a brightness temperature of 2360+-300 K in the IRAC-4.5 micron channel. This occultation depth suggests a low Bond albedo coupled to an inefficient heat transport from the planetary dayside to the nightside, or else possibly that the 4.5-micron observations probe atmospheric layers that are hotter than the maximum equilibrium temperature (i.e., a thermal inversion layer or a deep hot layer). The measured occultation phase and duration are consistent with a circular orbit and improves the 3-sigma upper limit on 55 Cnc e's orbital eccentricity from 0.25 to 0.06. [less ▲]

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See detailDetection of thin layers into concrete with static and CMP measurements
Van der Wielen, Audrey ULg; Courard, Luc ULg; Nguyen, Frédéric ULg

in 2012 14th International Conference on Ground Penetrating Radar (GPR) (2012, June)

Most concrete bridge decks contain a thin waterproofing layer, whose complex GPR signature can affect the detection of disorders or delaminations into the slab. In this study, we characterized the ... [more ▼]

Most concrete bridge decks contain a thin waterproofing layer, whose complex GPR signature can affect the detection of disorders or delaminations into the slab. In this study, we characterized the detection limits of our 2.3 GHz antenna for the detection of thin layers, with static and CMP measurements. In this last configuration, we showed that the radiation pattern and the reflection coefficient estimation are key parameters to use the inversion of the amplitude versus offset (AVO) curves for the estimation of the layer parameters. The theoretical results were compared to the results of FDTD simulations, performed with GprMax2D, and to laboratory measurements, performed on concrete slabs or sand containing thin layers. [less ▲]

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See detailDetection of transits of the nearby hot Neptune GJ 436 b
Gillon, Michaël ULg; Pont, F.; Demory, B*-O et al

in Astronomy and Astrophysics (2007), 472

This Letter reports on the photometric detection of transits of the Neptune-mass planet orbiting the nearby M-dwarf star GJ 436. It is by far the closest, smallest, and least massive transiting planet ... [more ▼]

This Letter reports on the photometric detection of transits of the Neptune-mass planet orbiting the nearby M-dwarf star GJ 436. It is by far the closest, smallest, and least massive transiting planet detected so far. Its mass is slightly larger than Neptune's at M = 22.6 ± 1.9 M_â . The shape and depth of the transit lightcurves show that it is crossing the host star disc near its limb (impact parameter 0.84 ± 0.03) and that the planet size is comparable to that of Uranus and Neptune, R = 25 200 ± 2200 km = 3.95 ± 0.35 R_â . Its main constituant is therefore very likely to be water ice. If the current planet structure models are correct, an outer layer of H/He constituting up to ten percent in mass is probably needed on top of the ice to account for the observed radius. [less ▲]

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See detailDetection of Tryptase in Bovine Mast Cells: Comparison of Enzyme- and Immuno-Histochemistry
Jolly, Sandra ULg; Coignoul, Freddy ULg; Gabriel, Annick ULg et al

in Journal of Comparative Pathology (1999), 120(3), 269-79

Mast cell (MC) phenotypes may vary with respect to tissue site, sensitivity to degranulating agents, dependency on T lymphocytes and, above all, the composition of their granules. Proteinases (either ... [more ▼]

Mast cell (MC) phenotypes may vary with respect to tissue site, sensitivity to degranulating agents, dependency on T lymphocytes and, above all, the composition of their granules. Proteinases (either trypsin-like or chymotrypsin-like) are granule constituents which provide an important means of distinguishing subtypes of MCs in man and rodents. The purpose of this study was to compare the distribution of MC trypsin-like protease (tryptase) in a variety of bovine tissues with the aim of examining MC heterogeneity. Tryptase was found in MCs regardless of their location within tissues. With respect to tryptase content, bovine MC distribution resembled more that of human and canine tissues than that of mice and rats. Comparison of the results yielded by enzyme- and immuno-histochemical staining suggested that a tryptase-negative, dual-specific chymase-positive MC subset occurred, at least in duodenal lamina propria, around bronchioles and within alveolar septa. The study also suggested that monoclonal antibodies raised against human tryptase can be used for quantitation of bovine tryptase in biological fluids; this offers a promising tool for evaluating the role of MC activation in disease. [less ▲]

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See detailDetection of Usutu virus in a bullfinch (Pyrrhula pyrrhula) and a great spotted woodpecker (Dendrocopos major) in north-west Europe
Garigliany, Mutien-Marie ULg; Marlier, Didier ULg; Tenner-Racz, Klara et al

in Veterinary Journal (2014), 199

In October 2012, a 3-year-old bullfinch (Pyrrhula pyrrhula) held in captivity for its entire lifespan and a wild adult great spotted woodpecker (Dendrocopos major), both with neurological signs, were ... [more ▼]

In October 2012, a 3-year-old bullfinch (Pyrrhula pyrrhula) held in captivity for its entire lifespan and a wild adult great spotted woodpecker (Dendrocopos major), both with neurological signs, were found 4 km from each other and 5 days apart in the Meuse Valley, Belgium. Non-suppurative encephalitis and mild degeneration and necrosis were identified in the brain and cerebellum, and Usutu virus antigen and RNA were detected by immunohistochemistry and real-time reverse transcriptase PCR, respectively. The two cases reported here represent the most western distribution of clinical disease in birds due to Usutu virus. [less ▲]

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See detailDetection of Vibrio cholerae, V. parahaemolyticus and V. vulnificus in seafood using real time PCR.
Lemaire, Cédric; Darcy; China, Bernard et al

Poster (2007, June)

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See detailDetection of viral genomes of caprine arthritis-encephalitis virus (CAEV) in semen and in genital tract tissues of male goat
Ali Al Ahmad, M. Z.; Fieni, F.; Pellerin, J. L. et al

in Theriogenology (2008)

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See detailDetection of visual pursuit in patients in minimally conscious state: a matter of stimuli and visual plane?
Thonnard, Marie; Wannez, Sarah ULg; Keen, Shannan et al

in Brain injury (2014), 28(9), 1164-70

OBJECTIVES: The aim of this study was to determine whether the assessment of pursuit eye movements in patients in minimally conscious state (MCS) is influenced by the choice of the visual stimulus (study ... [more ▼]

OBJECTIVES: The aim of this study was to determine whether the assessment of pursuit eye movements in patients in minimally conscious state (MCS) is influenced by the choice of the visual stimulus (study 1) and by the moving plane (study 2). METHODS: Patients with MCS (MCS- and MCS+) in the acute (<1 month post-injury) or chronic (>1 month) setting were assessed. The Coma Recovery Scale-Revised (CRS-R) procedure was used to test visual pursuit of a moving mirror, object and person (study 1, n = 88) and to test vertical and horizontal visual tracking (study 2, n = 94). RESULTS: Study 1: Patients with visual pursuit tracked preferentially the moving mirror over the moving person or object. Study 2: Patients displaying visual pursuit, especially in MCS- and in chronic setting, preferentially tracked on the horizontal rather than the vertical plane. CONCLUSION: The findings confirm the importance of using a mirror to assess visual pursuit in patients in MCS and of initiating testing using the horizontal plane, specifically in patients in MCS- and those in chronic setting. Assessment should then be done on the vertical plane if visual pursuit is not detected on the horizontal plane. [less ▲]

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See detailDetection of wheat root and straw in soil by use of Near Infrared hyperspectral imaging system and Partial Least Square discriminant analysis
Eylenbosch, Damien ULg; Fernández Pierna, Juan Antonio; Baeten, Vincent et al

Poster (2014, August 26)

Monitoring of root systems development and crop residues decomposition is only possible if these constituents can be discriminated from soil and quantified. In this work, Near Infrared (NIR) combined with ... [more ▼]

Monitoring of root systems development and crop residues decomposition is only possible if these constituents can be discriminated from soil and quantified. In this work, Near Infrared (NIR) combined with Hyperspectral Imaging (HSI) and Partial Least Square Discriminant Analysis (PLS-DA) is proposed as a new rapid and reliable method to discriminate soil, roots and straws. NIR-HSI provides simultaneously spectral and spatial information and PLS-DA allows discrimination between classes based on spectra of each pixel linked to chemical nature of sample constituents on the image. [less ▲]

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See detailDetection of wheat root and straw in soil by use of NIR hyperspectral imaging spectroscopy and Partial Least Square discriminant analysis
Eylenbosch, Damien ULg; Fernández Pierna, Juan Antonio; Baeten, Vincent et al

in Szilvássy, Zoltán; Pepó, Péter; Csajbók, József (Eds.) Book of Abstracts, ESA XIIIth Congress : ESA, Debrecen 25-29 August 2014 (2014, August)

Monitoring of root systems development and crop residues decomposition is only possible if these constituents can be discriminated from soil and quantified. In this work, Near Infrared (NIR) combined with ... [more ▼]

Monitoring of root systems development and crop residues decomposition is only possible if these constituents can be discriminated from soil and quantified. In this work, Near Infrared (NIR) combined with Hyperspectral Imaging (HSI) and Partial Least Square Discriminant Analysis (PLS-DA) is proposed as a new rapid and reliable method to discriminate soil, roots and straws. NIR-HSI provides simultaneously spectral and spatial information and PLS-DA allows discrimination between classes based on spectra of each pixel linked to chemical nature of sample constituents on the image. [less ▲]

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See detailDetection of wrong analysis with Diva
Troupin, Charles ULg

Report (2011)

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See detailDétection précoce de l'hyperparathyroïdie secondaire : impact de l'établissement des valeurs de références de la parathormone
Cavalier, Etienne ULg; Delanaye, Pierre ULg; Beckers, Albert ULg

in 27ème Congrès de la Société Française d'Endocrinologie - Deauville, 29 septembre - 2 octobre 2010 (2010, September)

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See detailLa détection précoce de la maladie d'Alzheimer
Bastin, Christine ULg

Conference (2015, November 17)

Lorsque le diagnostic de maladie d’Alzheimer est posé, les atteintes au niveau du cerveau et l’ampleur des difficultés dans la vie quotidienne ont atteint un seuil critique. Actuellement, les chercheurs ... [more ▼]

Lorsque le diagnostic de maladie d’Alzheimer est posé, les atteintes au niveau du cerveau et l’ampleur des difficultés dans la vie quotidienne ont atteint un seuil critique. Actuellement, les chercheurs et les cliniciens pensent que pour tenter de retarder l’apparition d’une démence, voire même l’empêcher, il faut agir bien avant que les premiers symptômes majeurs apparaissent. Le défi actuel est de trouver les meilleurs outils permettant de détecter le plus tôt possible les premiers signes de la maladie. Etant donné que des changements cognitifs peuvent être détectés très tôt, les neuropsychologues tentent d’identifier parmi les tests qui forment le bilan neuropsychologique ceux qui permettent de prédire au mieux le développement futur d’une maladie d’Alzheimer. Les recherches ont suggéré que les mesures ayant le meilleur pouvoir de prédiction semblent être celles de mémoire épisodique (qui est la capacité à se souvenir d’événements vécus dans un contexte bien précis) et les mesures de fluence verbale (qui est la capacité à citer un grand nombre de mots appartenant à une catégorie ou commençant par une lettre donnée). Le groupe Vieillissement et Mémoire, au sein du Centre de Recherches du Cyclotron (Université de Liège), poursuit actuellement deux lignes de recherche en lien avec la question de la détection précoce de la maladie d’Alzheimer : Premièrement, nous tentons de déterminer si nous pouvons encore mieux détecter les personnes à risque de développer une maladie d’Alzheimer en affinant les mesures de la mémoire. Le point de départ de cette recherche doit être une compréhension approfondie des mécanismes qui régissent le fonctionnement de la mémoire ainsi que de leurs bases cérébrales. Nos premiers résultats ont montré une perte précoce de la capacité à réactiver tous les détails d’un épisode vécu, associée à une déconnexion entre les régions d’un réseau cérébral incluant le cortex cingulaire postérieur et l’hippocampe. Deuxièmement, nous étudions les facteurs protecteurs qui permettent à certaines personnes de mieux résister que d’autres aux effets négatifs du vieillissement et de la pathologie cérébrale. Une étude non encore publiée menée auprès de personnes âgées sans trouble cognitif a montré que plus les personnes avaient étudié longtemps et avaient pratiqué une activité physique au cours de leur vie, meilleure était leur capacité à se souvenir des détails des événements vécus. Enfin, une approche idéale pour Identifier le plus tôt possible qui risque de développer des symptômes de déclin cognitif est l’approche multidisciplinaire. Plutôt que d’évaluer l’intérêt d’une mesure seule, nous proposons de tenir compte de manière combinée des différents éléments qui semblent contribuer à la détection précoce de la maladie d’Alzheimer : modifications neuropathologiques, mesures neuropsychologiques, mesures de la structure et du fonctionnement cérébral, habitudes de vie, changements physiologiques et modification du sommeil. [less ▲]

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See detailDétection précoce de la souffrance psychique chez l’adolescent
Malchair, Alain ULg

Scientific conference (2014, October 03)

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