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See detailExploring the gravitationally lensed system HE 1104-1805: near-IR spectroscopy
Courbin, F.; Lidman, C.; Meylan, G. et al

in Astronomy and Astrophysics (2000), 360

A new technique for the spatial deconvolution of spectra is applied to near-IR (0.95-2.50 mum) NTT/SOFI spectra of the lensed, radio-quiet quasar HE 1104-1805. The continuum of the lensing galaxy is ... [more ▼]

A new technique for the spatial deconvolution of spectra is applied to near-IR (0.95-2.50 mum) NTT/SOFI spectra of the lensed, radio-quiet quasar HE 1104-1805. The continuum of the lensing galaxy is revealed between 1.5 mum and 2.5 mum. Although the spectrum does not show strong emission features, it is used in combination with previous optical and IR photometry to infer a plausible redshift in the range 0.8 < z < 1.2. Modeling of the system shows that the lens is complex, probably composed of the red galaxy seen between the quasar images and a more extended component associated with a galaxy cluster with fairly low velocity dispersion (~ 575 km s[SUP]-1[/SUP]). Unless more constrains can be put on the mass distribution of the cluster, e.g. from deep X-ray observations, HE 1104-1805 will not be a good system to determine H[SUB]0[/SUB]. We stress that multiply imaged quasars with known time delays may prove more useful as tools for detecting dark mass in distant lenses than for determining cosmological parameters. The spectra of the two lensed images of the source are of great interest. They show no trace of reddening at the redshift of the lens nor at the redshift of the source. This supports the hypothesis of an elliptical lens. Additionally, the difference between the spectrum of the brightest component and that of a scaled version of the faintest component is a featureless continuum. Broad and narrow emission lines, including the FeII features, are perfectly subtracted. The very good quality of our spectrum makes it possible to fit precisely the optical Fe II feature, taking into account the underlying continuum over a wide wavelength range. HE 1104-1805 can be classified as a weak Fe II emitter. Finally, the slope of the continuum in the brightest image is steeper than the continuum in the faintest image and supports the finding by Wisotzki et al. (1993) that the brightest image is microlensed. This is particularly interesting in view of the new source reconstruction methods from multiwavelength photometric monitoring. While HE 1104- 1805 does not seem the best target for determining cosmological parameters, it is probably the second most interesting object after Q 2237+0305 (the Einstein cross), in terms of microlensing. Based on observations collected with the ESO New Technology Telescope (program 61.B-0413) [less ▲]

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See detailExploring the Holocene through fossil cyanobacterial sequences from Antarctic lake sediments.
Fernandez Carazo, Rafael ULg; Waleron, Krzysztof; Hodgson, Dominic et al

Poster (2009, July 27)

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See detailExploring the Interest in and the Usage of the Internet Among Patients Eligible for Osteoporosis Screening.
Slomian, Justine ULg; Reginster, Jean-Yves ULg; Gaspard, Ulysse ULg et al

in Calcified tissue international (2015), 96

The aim of this study was to evaluate the interest in the Internet and its usage for health-related issues among people eligible for osteoporosis screening. Self-administered questionnaires have been ... [more ▼]

The aim of this study was to evaluate the interest in the Internet and its usage for health-related issues among people eligible for osteoporosis screening. Self-administered questionnaires have been distributed to subjects who were screened for osteoporosis and to menopausal women. 177 patients have responded to the survey (64.5 +/- 10.1 years, 88.1 % of women). There are 78.5 % of Internet users. Among them, 67.2 % said searching information about their health and 74.5 % said using the Internet for this purpose. All respondents attributed an average score, out of 10, of 5.7 +/- 2.3 regarding the reliability of information that they could find on the Internet. The use of the Internet differs significantly depending on age: those who use the Internet are younger (62.1 +/- 8.91 years) than those who do not use it (73.3 +/- 9.42 years). The socioeconomic status also has an impact on the Internet use: Internet users have a higher education, are more professionally active and have a higher net monthly household income compared to the group of non-users. Even if age and socioeconomic status appear to be determining factors in the use of the Internet for the search of health information in patients eligible for osteoporosis screening, almost 75 % of the study population use the Internet for this purpose. Action to promote health through an Internet platform must therefore take these parameters into account. [less ▲]

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See detailExploring the L1-L2 Relationship in the L2 Acquisition of Prosody
Rasier, Laurent ULg; Hiligsmann, Philippe

E-print/Working paper (2009)

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See detailExploring the L1-L2 relationship in the L2 acquisition of prosody
Rasier, Laurent ULg; Hiligsmann, Philippe

Conference (2009)

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See detailExploring the magnetic topologies of cool stars
Morin, J.; Donati, J *-F; Petit, P. et al

in IAU Symposium Proceedings (2010, September 01)

Magnetic fields of cool stars can be directly investigated through the study of the Zeeman effect on photospheric spectral lines using several approaches. With spectroscopic measurement in unpolarised ... [more ▼]

Magnetic fields of cool stars can be directly investigated through the study of the Zeeman effect on photospheric spectral lines using several approaches. With spectroscopic measurement in unpolarised light, the total magnetic flux averaged over the stellar disc can be derived but very little information on the field geometry is available. Spectropolarimetry provides a complementary information on the large-scale component of the magnetic topology. With Zeeman-Doppler Imaging (ZDI), this information can be retrieved to produce a map of the vector magnetic field at the surface of the star, and in particular to assess the relative importance of the poloidal and toroidal components as well as the degree of axisymmetry of the field distribution. The development of high-performance spectropolarimeters associated with multi-lines techniques and ZDI allows us to explore magnetic topologies throughout the Hertzsprung-Russel diagram, on stars spanning a wide range of mass, age and rotation period. These observations bring novel constraints on magnetic field generation by dynamo effect in cool stars. In particular, the study of solar twins brings new insight on the impact of rotation on the solar dynamo, whereas the detection of strong and stable dipolar magnetic fields on fully convective stars questions the precise role of the tachocline in this process. [less ▲]

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See detailExploring the major depletions of conodont diversity during the Triassic
Martínez-Pérez, Carlos; Cascales - Miñana, Borja ULg; Plasencia, Pablo et al

in Historical Biology (2015), 27(5), 503-507

In this paper, we show that the Triassic fossil record reflects just two great depletions of conodont diversity before the Rhaetian, which occurred in the Smithian (Olenekian, Early Triassic) and in the ... [more ▼]

In this paper, we show that the Triassic fossil record reflects just two great depletions of conodont diversity before the Rhaetian, which occurred in the Smithian (Olenekian, Early Triassic) and in the Julian (Carnian, Late Triassic). By exploring this context, our results highlighted that they respond to different origination-extinction dynamics. Thus, while the Smithian diversity depletion can be interpreted as a consequence of elevated extinction, the Julian diversity depletion was triggered by fluctuations in origination regime. This evidence suggests that, despite the role of extinction on diversity losses, conodonts suffered crucial changes on the origination regimes during the Late Triassic which triggered these events. Notwithstanding, our results indicate that the end-Triassic diversity depletion of conodonts was produced by background extinction levels in a context of lower origination. This suggests that several biological factors, rather than a unique, environmental and/or cyclic cause, could have influenced the evolutionary history of conodonts during the Triassic. © 2014 © 2014 Taylor & Francis. [less ▲]

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See detailExploring the night sky with binoculars -- P. Moore
Manfroid, Jean ULg

in Ciel et Terre (1987), 103

Not Available

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See detailExploring the nucleon structure through GPDs and TDAs in hard exclusive processes
Pire, Bernard; Semenov-Tyan-Shanskiy, Kirill ULg; Szymanowski, Lech et al

Conference (2011)

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See detailExploring the origin of magnetic fields in massive stars: II. New magnetic field measurements in cluster and field stars
Hubrig, S.; Schoeller, M.; Ilyin, I. et al

in Astronomy and Astrophysics (2013), 551

Theories on the origin of magnetic fields in massive stars remain poorly developed, because the properties of their magnetic field as function of stellar parameters could not yet be investigated. To ... [more ▼]

Theories on the origin of magnetic fields in massive stars remain poorly developed, because the properties of their magnetic field as function of stellar parameters could not yet be investigated. To investigate whether magnetic fields in massive stars are ubiquitous or appear only in stars with a specific spectral classification, certain ages, or in a special environment, we acquired 67 new spectropolarimetric observations for 30 massive stars. Among the observed sample, roughly one third of the stars are probable members of clusters at different ages, whereas the remaining stars are field stars not known to belong to any cluster or association. Spectropolarimetric observations were obtained during four different nights using the low-resolution spectropolarimetric mode of FORS2 (FOcal Reducer low dispersion Spectrograph) mounted on the 8-m Antu telescope of the VLT. Furthermore, we present a number of follow-up observations carried out with the high-resolution spectropolarimeters SOFIN mounted at the Nordic Optical Telescope (NOT) and HARPS mounted at the ESO 3.6m between 2008 and 2011. To assess the membership in open clusters and associations, we used astrometric catalogues with the highest quality kinematic and photometric data currently available. The presence of a magnetic field is confirmed in nine stars previously observed with FORS1/2: HD36879, HD47839, CPD-282561, CPD-472963, HD93843, HD148937, HD149757, HD328856, and HD164794. New magnetic field detections at a significance level of at least 3sigma were achieved in five stars: HD92206c, HD93521, HD93632, CPD-468221, and HD157857. Among the stars with a detected magnetic field, five stars belong to open clusters with high membership probability. According to previous kinematic studies, five magnetic O-type stars in our sample are candidate runaway stars. [less ▲]

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See detailExploring the plant diversity through time: inference and bias
Cascales - Miñana, Borja ULg; Cleal, Christopher J.

Scientific conference (2014, November)

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See detailExploring the potential of crop specific green area index time series to improve yield estimation at regional scale
Duveiller, Gregory; de Wit, Allard; Kouadio, Amani Louis ULg et al

in Sobrino, J. A. (Ed.) Proceedings of the 3rd International Symposium on Recent Advances in Quantitative Remote Sensing (RAQRS'III) (2010)

Crop status, such as the Green Area Index (GAI), can be retrieved from satellite observations by modelling and inverting the radiative transfer within the canopy. Providing such information along the ... [more ▼]

Crop status, such as the Green Area Index (GAI), can be retrieved from satellite observations by modelling and inverting the radiative transfer within the canopy. Providing such information along the growing season can potentially improve crop growth modelling and yield estimation. However, such approaches have proven difficult to apply on coarse resolution satellite data due to the fragmented land cover in many parts of the World. Advances in operational crop mapping will sooner or later allow the production of crop maps relatively early in the crop growth season, thereby providing an opportunity to sample pixels from medium/coarse spatial resolution data with relatively high cover fraction of a particular crop type to derive crop specific GAI time series. This research explores how to use such time series derived from MODIS to produce indicators of crop yield using two approaches over part of Belgium. The first method consists in looking at metrics of the decreasing part of the GAI curves when senescence occurs. Such metrics, like the position of the inflexion point, have been shown to be significantly correlated to yield. The second approach is to optimize the WOFOST model used in the European Crop Growth Monitoring System (CGMS) based on the GAI time series. Results show that, although the optimized model shows considerably better performance than the model running on the default parameter, the model is sometimes outperformed by the simpler metric approach. In all cases, indicators including remote sensing information provide better estimates that the average yield of previous years. [less ▲]

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See detailExploring the relationship between new word learning and short-term memory for serial order recall, item recall, and item recognition
Majerus, Steve ULg; Poncelet, Martine ULg; Elsen, B. et al

in European Journal of Cognitive Psychology (2006), 18(6), 848-873

We reexplored the relationship between new word learning and verbal short-term memory (STM) capacities, by distinguishing STM for serial order information, item recall, and item recognition. STM ... [more ▼]

We reexplored the relationship between new word learning and verbal short-term memory (STM) capacities, by distinguishing STM for serial order information, item recall, and item recognition. STM capacities for order information were estimated via a serial order reconstruction task. A rhyme probe recognition task assessed STM for item recognition. Item recall capacities were derived from the proportion of item errors in an immediate serial recall task. In Experiment 1, strong correlations were observed between item recall and item recognition, but not between the item STM tasks and the serial order task, supporting recent theoretical positions that consider that STM for item and serial order rely on distinct capacities. Experiment 2 showed that only the serial order reconstruction task predicted independent variance in a paired associate word - nonword learning task. Our results suggest that STM capacities for serial order play a specific and causal role in learning new phonological information. [less ▲]

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See detailExploring the risk factors for Salmonella in the ten biggest Belgian pig slaughterhouses.
Delhalle, Laurent ULg; Desadeleer, L.; Bollaerts, K. et al

Poster (2007, May)

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See detailExploring the role of base words and suffixes in word and pseudoword processing: Evidence from young French readers
Quemart, Pauline ULg; Casalis, Séverine; Duncan, Lynne

in Scientific Studies of Reading (2012), (5), 424-442

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See detailExploring the schizophrenic hyperreflexivity on the Rorschach test
Englebert, Jérôme ULg; Bataille, Jennifer; Mormont, Christian ULg et al

Poster (2015, August 28)

L’hyper-réflexivité schizophrénique peut être définie comme une attitude particulière de la conscience consistant à interroger de façon explicite et réflexive des phénomènes généralement implicites et ... [more ▼]

L’hyper-réflexivité schizophrénique peut être définie comme une attitude particulière de la conscience consistant à interroger de façon explicite et réflexive des phénomènes généralement implicites et préréflexifs (Sass, 2014). Notre hypothèse est que ce mécanisme se manifeste dans les protocoles du test de Rorschach des sujets schizophrènes (Englebert, 2013). Pour l’éprouver, nous avons administré le test à douze sujets schizophrènes. L’originalité de cette recherche repose sur une seconde présentation des planches (trois jours plus tard) qui a permis d’évoquer avec les sujets la permanence de leurs perceptions et de discuter de l’acception commune de celles-ci (pensez-vous que la plupart des autres personnes pourrait voir ce que vous voyez ?). Les résultats confirment notre hypothèse, tant au niveau quantitatif (les marqueurs de l’hyper-réflexivité que nous avions identifiés se retrouvent dans la majorité des protocoles) que qualitatif (phrases suggérant une interrogation épistémologique du test, par exemple). Enfin, nous remarquerons que l’attitude schizophrénique envers le test de Rorschach est assez subtile puisqu’elle identifie le fondement épistémologique du test reposant sur la nécessité d’une fausse perception – une « violation de la réalité » selon Exner (2003). Les sujets schizophrènes mettent en évidence la règle implicite sur laquelle repose le test qui consiste à ne pas donner la seule véritable bonne réponse (systématique) au test qui est « une tache ». [less ▲]

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See detailExploring the sky
Nazé, Yaël ULg

Poster (2013)

Detailed reference viewed: 12 (0 ULg)