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See detailImprints of the quasar structure in time-delay light curves: Microlensing-aided reverberation mapping
Sluse, Dominique ULg; Tewes, M.

in Astronomy and Astrophysics (2014), 571(A60), 10

Owing to the advent of large area photometric surveys, the possibility to use broad band photometric data, instead of spectra, to measure the size of the broad line region of active galactic nuclei, has ... [more ▼]

Owing to the advent of large area photometric surveys, the possibility to use broad band photometric data, instead of spectra, to measure the size of the broad line region of active galactic nuclei, has raised a large interest. We describe here a new method using time-delay lensed quasars where one or several images are affected by microlensing due to stars in the lensing galaxy. Because microlensing decreases (or increases) the flux of the continuum compared to the broad line region, it changes the contrast between these two emission components. We show that this effect can be used to effectively disentangle the intrinsic variability of those two regions, offering the opportunity to perform reverberation mapping based on single band photometric data. Based on simulated light curves generated using a damped random walk model of quasar variability, we show that measurement of the size of the broad line region can be achieved using this method, provided one spectrum has been obtained independently during the monitoring. This method is complementary to photometric reverberation mapping and could also be extended to multi-band data. Because the effect described above produces a variability pattern in difference light curves between pairs of lensed images which is correlated with the time-lagged continuum variability, it can potentially produce systematic errors in measurement of time delays between pairs of lensed images. Simple simulations indicate that time-delay measurement techniques which use a sufficiently flexible model for the extrinsic variability are not affected by this effect and produce accurate time delays. [less ▲]

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See detailComment je traite … Recommandations pour surveiller et optimiser un traitement médicamenteux en cours
SCHEEN, André ULg

in Revue Médicale de Liège (2014), 69(11), 581-585

Any pharmacological treatment should ideally be effective and safe. The supervision of an ongoing therapy should control that individualized goals are reached while tolerance and safety are present. In ... [more ▼]

Any pharmacological treatment should ideally be effective and safe. The supervision of an ongoing therapy should control that individualized goals are reached while tolerance and safety are present. In case of not reaching the predefined objectives, the causes of failure should first be screened (for instance, exclusion of poor patient compliance), and the treatment should be then optimized : dose adjustment, add-on of another drug (if possible synergistic combination) and/or shift to a more effective pharmacological therapy. In some cases, therapeutic monitoring may be useful or even mandatory in order to better adjust drug dosing and thus guarantee both efficacy and safety. [less ▲]

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See detailHighly sophisticated compound droplets on fiber arrays
Weyer, Floriane ULg; Lismont, Marjorie ULg; Dreesen, Laurent ULg et al

Poster (2014, November)

The poster shows a drop of oil containing four soapy water droplets of four different colors : red, orange, green and blue. This sophisticated object is created thanks to a fiber array. Fiber networks ... [more ▼]

The poster shows a drop of oil containing four soapy water droplets of four different colors : red, orange, green and blue. This sophisticated object is created thanks to a fiber array. Fiber networks allow processes such as droplet motion, fragmentation, trapping, releasing, mixing and encapsulation. Therefore, by using a vertical fiber decorated with successive nodes, compound droplets can be created. A soapy water droplet, with a specific color, is placed at each intersection. Then, a silicon oil droplet glides along the vertical fiber, encapsulates and collects the water droplets at each node leading to the formation of a compound droplet with four different components. [less ▲]

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See detailEarly detection of university students in potential difficulty : a case study
Hoffait, Anne-Sophie ULg; Schyns, Michael ULg

Conference (2014, November)

Rate of success in the first year at University in Belgium is very low regarding other foreign universities. The University of Liege, as other Universities, has already taken different initiatives. But by ... [more ▼]

Rate of success in the first year at University in Belgium is very low regarding other foreign universities. The University of Liege, as other Universities, has already taken different initiatives. But by early identifying students who have a high probability to face difficulties if nothing is done, the Universities might develop adapted methods to attack the problem with more emphasis where it is more needed and when it is still possible. Thus we want to develop a decision tool able to identify these students to help them. For that, we consider three standard datamining methods: logistic regression, artificial neural networks and decision trees and focus on early detection, i.e. before starting at the University. Then, we suggest to adapt these three methods as well as the classification framework in order to increase the probability of correct identification of the students. In our approach, we do not restrict the classification to two extreme classes, e.g. failure or success, but we create subcategories for different levels of confidence: high risk of failure, risk of failure, expected success or high probability of success. The algorithms are modified accordingly and to give more weight to the class that really matters. Note that this approach remains valid for any other classification problems for which the focus is on some extreme classes; e.g. fraud detection, credit default... Finally, simulations are conducted to measure the performances of the three methods, with and without the suggested adaptation. We check if the factors of success/failure we can identify are similar to those reported in the literature. We also make a ``what-if sensitivity analysis''. The goal is to measure in more depth the impact of some factors and the impact of some solutions, e.g., a complementary training or a reorientation. [less ▲]

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See detailLa bibliothèque ouverte : hommage à Christine Pagnoulle
Decoster, Sara ULg

in Culture, le Magazine Culturel de l'Université de Liège (2014), hors série

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See detailMapping the electron energy in Jupiter’s aurora: Hubble spectral observations
Gérard, Jean-Claude ULg; Bonfond, Bertrand ULg; Grodent, Denis ULg et al

in Journal of Geophysical Research. Space Physics (2014), 119

Far ultraviolet spectral observations have been made with the Hubble Space Telescope in the time-tag mode using the Space Telescope Imaging Spectrograph (STIS) long slit. The telescope was slewed in such ... [more ▼]

Far ultraviolet spectral observations have been made with the Hubble Space Telescope in the time-tag mode using the Space Telescope Imaging Spectrograph (STIS) long slit. The telescope was slewed in such a way that the slit projection scanned from above the polar limb down to midlatitudes, allowing us to build up the first spectral maps of the FUV Jovian aurora. The shorter wavelengths are partly absorbed by the methane layer overlying part of the auroral emission layer. The long-wavelength intensity directly reflects the precipitated energy flux carried by the auroral electrons. Maps of the intensity ratio of the two spectral regions have been obtained by combining spectral emissions in two wavelength ranges. They show that the amount of absorption by methane varies significantly between the different components of the aurora and inside the main emission region. Some of the polar emissions are associated with the hardest precipitation, although the auroral regions of strong electron precipitation do not necessarily coincide with the highest electron energies. Outputs from an electron transport model are used to create maps of the distribution of the characteristic electron energies. Using model atmospheres adapted to auroral conditions, we conclude that electron energies range between a few tens to several hundred keV. Comparisons of derived energies are in general agreement with those calculated from magnetosphere-ionosphere coupling models, with values locally exceeding the standard model predictions. These results will provide useful input for three-dimensional modeling of the distribution of particle heat sources into the high-latitude Jovian upper atmosphere. [less ▲]

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See detailLa dépression à l'adolescence: Quels signes ? Quand s'inquiéter ?
Boulard, Aurore ULg

in Eduquer : Tribune Laïque (2014), 109

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See detailThe role of olfaction in wireworms: a review on foraging behavior and sensory apparatus
Barsics, Fanny ULg; Haubruge, Eric ULg; Francis, Frédéric ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2014), 18(4), 524-535

Introduction Integrated management of wireworms (Coleoptera: Elateridae) depends upon approaches applied both above- and belowground, and over several spatial scales. While foraging, these soil pests use ... [more ▼]

Introduction Integrated management of wireworms (Coleoptera: Elateridae) depends upon approaches applied both above- and belowground, and over several spatial scales. While foraging, these soil pests use biotic and abiotic signals to orientate towards target plant organs. Development of efficient techniques for implementation in integrated strategies relies upon improved knowledge of this process. In particular, an important step consists of elucidating the role of volatile organic compounds (VOC), emitted by belowground plant organs, in wireworm chemical ecology. This would have a positive impact on push-pull strategies and varietal selection developed against these insects. Literature In this work, we summarized the available data regarding wireworm foraging behavior as well as variables that should be considered when studying the potential role of plant-produced volatile semiochemicals. This includes CO2 gradients and other host-related cues, temperature, relative humidity and soil moisture, and wireworm physiological stage. We also review what is known of the sensory apparatus of wireworms, since this is involved in every step of the foraging process. Conclusion Some baseline data for studying VOC related wireworm foraging behavior exists. Using it as a tool in applied entomology should result in discovery of the semiochemicals that underpin trophic interactions involving these pests. However, most of the key pest species are not fully described with regards to the parameters detailed here. Obtaining accurate information to fill the current knowledge gaps will be needed in order to devise new integrated management strategies. [less ▲]

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See detailLa sociologie implicite de la littérature
Ledent, David ULg

in Narrative Knowing / Récit et savoir (2014, November)

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See detailReference values for the craniocervical flexion test in healthy volunteers
Demoulin, Christophe ULg; Hody, Stéphanie ULg; GROSDENT, Stéphanie ULg et al

in Abstract Book of 7th Biennial Congress of The Belgian Back Society (2014, November)

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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 detailLe numerique dans l'aide multilatérale en matière de culture
Vlassis, Antonios ULg

Article for general public (2014)

En premier lieu, le numéro de novembre traite de la place du numérique dans l’aide multilatérale en matière d’industries culturelles, se penchant sur le programme ACPCultures+ financé par l’Union ... [more ▼]

En premier lieu, le numéro de novembre traite de la place du numérique dans l’aide multilatérale en matière d’industries culturelles, se penchant sur le programme ACPCultures+ financé par l’Union européenne (UE) et géré par le Secrétariat du Groupe des pays ACP (Afrique, Caraïbes, Pacifique). En deuxième lieu, nous traitons de l’évolution récente des négociations commerciales, et surtout du mandat du Conseil européen ‐ rendu public au début d’octobre ‐ pour les négociations pour un partenariat transatlantique entre l’UE et les États‐Unis. En troisième lieu, nous mettons l’accent sur un grand nombre de questions centrales de la gouvernance mondiale de la culture, telles que la Déclaration de Florence sur le lien entre le développement et la culture, le rapport de la Motion Picture Association of America (MPAA) au sujet des marchés notoires en termes de piratage numérique et physique, le rapport sur l’égalité des genres et le secteur culturel, ainsi que le rapport sur la contribution des industries créatives dans l’économie européenne. [less ▲]

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See detailLa strega, la contessa, il ragno. Sciascia e i differenziali della storia
Fichera, Gabriele ULg

in Todo modo. Rivista internazionale di studi sciasciani (2014), Anno IV

Analysing 1912 + 1, this essay sets out to demonstrate the ways in which Sciascia’s blending of fiction and history addresses the contentious issue of identifying truth. It examines the intricate ... [more ▼]

Analysing 1912 + 1, this essay sets out to demonstrate the ways in which Sciascia’s blending of fiction and history addresses the contentious issue of identifying truth. It examines the intricate philosophical links between freedom and necessity, and compares Sciascia’s writing with that of authors who were dear to him, such as Diderot, Manzoni, Tolstoj and Savinio. [less ▲]

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See detailSpasticity in disorders of consciousness: a behavioral study
Thibaut, Aurore ULg; Chatelle, Camille ULg; Wannez, Sarah ULg et al

in European Journal of Physical Medicine & Rehabilitation (2014)

Background: Spasticity is a frequent complication after severe brain injury, which may impede the rehabilitation process and diminish the patients’ quality of life. Aim: We here investigate the presence ... [more ▼]

Background: Spasticity is a frequent complication after severe brain injury, which may impede the rehabilitation process and diminish the patients’ quality of life. Aim: We here investigate the presence of spasticity in a population of non-communicative patients with disorders of consciousness. We also evaluate the correlation between spasticity and potential factors of co-morbidity, frequency of physical therapy, time since insult presence of pain, presence of tendon retraction, etiology and diagnosis. Design: Cross sectional study. Setting: University Hospital of Liège, Belgium. Population: 65 patients with chronic (>3 months post insult) disorders of consciousness were included (22 women; mean age: 44±14y; 40 with traumatic etiology; 40 in a minimally conscious state; time since insult: 39±37months). Methods: Spasticity was measured with the Modified Ashworth Scale (MAS) and pain was assessed using the Nociception Coma Scale-Revised (NCS-R). Results: Out of 65 patients, 58 demonstrated signs of spasticity (89%; MAS ≥ 1), including 39 who showed severe spasticity (60%; MAS ≥ 3). Patients with spasticity receiving anti-spastic medication were more spastic than unmedicated patients. A negative correlation was observed between the severity of spasticity and the frequency of physical therapy. MAS scores correlated positively with time since injury and NCS-R scores. We did not observe a difference of spasticity between the diagnostic. Conclusion: A large proportion of patients with disorders of consciousness develop severe spasticity, possibly affecting their functional recovery and their quality of life. The observed correlation between degrees of spasticity and pain scores highlights the importance of pain management in these patients with altered states of consciousness. Finally, the relationship between spasticity and treatment (i.e., pharmacological and physical therapy) should be further investigated in order to improve clinical care. Clinical Rehabilitation Impact: Managing spasticity at first signs could improve rehabilitation of patients with disorders of consciousness and maximize their chances of recovery. In addition, decreasing this trouble could allow a better quality of life for these non-communicative patients. [less ▲]

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See detailThe effect of sampling effort on mammalian paleodiversity: the fossil record of large and small mammals compared
Santaella, Beatriz; Figueirido, Borja; Cascales - Miñana, Borja ULg et al

in Journal of Vertebrate Paleontology, Program and Abstracts, 2014 (2014, November)

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See detailIl faut agir sur les structures et les pratiques
Lafontaine, Dominique ULg

in Wallonie : Revue du Conseil Economique et Social de la Région Wallonne (2014), (124), 16-19

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See detailSpace Weather at Saturn - Auroral observations
Radioti, Aikaterini ULg; Grodent, Denis ULg; Gérard, Jean-Claude ULg et al

Conference (2014, November)

Unlike to Earth, Saturn is a fast rotator and its magnetosphere is dominated by fast planetary rotation and internally driven processes. However, the interaction of the solar wind with Saturn’s ... [more ▼]

Unlike to Earth, Saturn is a fast rotator and its magnetosphere is dominated by fast planetary rotation and internally driven processes. However, the interaction of the solar wind with Saturn’s magnetosphere is not negligible and it is manifested among others in the auroral region. The interplanetary magnetic field reconnects with the dayside magnetopause at Saturn and results in enhancements in the auroral emission accompanied by entry of significant amount of open flux in the magnetosphere. The solar wind affects also the nightside magnetosphere. Dramatic enhancements of the nightside-dawn auroral emissions have been attributed to solar wind-induced auroral storms. Additionally, recent auroral observations revealed the presence of a transpolar arc at Saturn, one of the most spectacular auroral features at Earth, which could be possibly related to solar wind driven tail reconnection. Finally, there is evidence of viscous interaction of the solar wind with Saturn’s magnetosphere, which involves magnetic reconnection on a small scale. [less ▲]

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