References of "Scientific congresses and symposiums"
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See detailCharacteristics of Saturn's polar atmosphere and auroral electrons derived from HST/STIS, FUSE and Cassini/UVIS spectra
Gustin, Jacques ULg; Pryor, W.; Feldman, P. et al

Poster (2008, December 01)

Ultraviolet spectra of Saturn's aurora obtained with the Hubble Space Telescope Imaging Spectrograph (STIS), the Cassini Ultraviolet Imaging Spectrograph (UVIS) and the Far Ultraviolet Spectroscopic ... [more ▼]

Ultraviolet spectra of Saturn's aurora obtained with the Hubble Space Telescope Imaging Spectrograph (STIS), the Cassini Ultraviolet Imaging Spectrograph (UVIS) and the Far Ultraviolet Spectroscopic Explorer (FUSE) have been compared to synthetic spectra of electron-excited H2 in order to derive various auroral characteristics, such as the energy of the primary precipitating electrons and the H2 temperature at the altitude of the aurora. Two physical processes have been exploited: the absorption by hydrocarbons in the FUV and H2 self-absorption in the EUV. We find energies in the range 10-18 keV, which locates Saturns's aurora between 0.1 and 0.3 μ bar. We also determined that the auroral H2 emission is characterized by a temperature of ~400K, consistent with temperatures measured in the infrared, but much higher than what is expected from equatorial atmospheric models. These new results bring valuable constraints on both polar atmospheric models and theoretical studies of the ionosphere-magnetosphere coupling. [less ▲]

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See detailIntérêt de l'évaluation de l'efficacité d'une prise en charge
Adam, Stéphane ULg

Conference (2008, December 01)

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See detailNeutral Ion Coupling Explorer satellite measurements of thermospheric composition, winds and temperatures.
Mende, S. B.; Immel, T. J.; England, S. et al

Conference (2008, December 01)

A new Small Explorer mission, the Neutral Ion Coupling Explorer (NICE) mission, was selected for study by NASA to specifically address neutral ion coupling in the Earth's atmosphere. The main goal of NICE ... [more ▼]

A new Small Explorer mission, the Neutral Ion Coupling Explorer (NICE) mission, was selected for study by NASA to specifically address neutral ion coupling in the Earth's atmosphere. The main goal of NICE is to study neutral-ion coupling at low latitudes where the densest plasma in geospace is created and where a number of remarkable interactions between the plasma and neutral gas occur even in the relative absence of high-latitude forcing. NICE will study this region from a ~24 degree inclination 550 km circular orbit, residing entirely on closed magnetic field lines. The relatively fast precession of low-inclination orbit is favorable for frequent sampling of all local times for the determination of tidal structures. It is now widely recognized that the neutral thermosphere has a strong influence on the ionosphere and that Earth's ionosphere at quiet times is actually tidally dominated. The NICE concept is unique in simultaneously providing measurements of the parameters relevant to ion production and motion across the entire altitude range of the low-latitude ionosphere. The science payload consists of 3 remote sensing instruments viewing the atmospheric limb (1) a dual Doppler Fabry-Perot Interferometer (FP), scanning in altitude to measure neutral wind vector and temperature altitude profiles in the E- and F-regions, (2) a Far Ultraviolet (FUV) imager to measure daytime neutral composition and image the nighttime F-layer intensity distributions, and (3) an Extreme Ultraviolet (EUV) altitude profiler to retrieve daytime F-layer properties. In addition, an Ion Velocity Meter (IVM) measures the in-situ ion drifts. NICE will take advantage of an elegant choice of orbit and instrument viewing geometries to make coordinated and complementary observations at all local times, with optimal conjunction of measurements occurring near the equator. The observations are accompanied by a suite of advanced numerical models and analysis techniques. [less ▲]

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See detailLong-term Brightness Variations of the Io UV Footprint
Bonfond, Bertrand ULg; Grodent, Denis ULg; Gérard, Jean-Claude ULg et al

Conference (2008, December 01)

Since the finding of the UV Io footprint in 1996, the successive UV instruments on board the Hubble Space Telescope (HST) allowed us to considerably improve the understanding of the Io-Jupiter electro ... [more ▼]

Since the finding of the UV Io footprint in 1996, the successive UV instruments on board the Hubble Space Telescope (HST) allowed us to considerably improve the understanding of the Io-Jupiter electro-magnetic interaction and its auroral counterpart. It has been shown that the Io footprint is generally formed by one bright spot preceded or followed by secondary spots whose relative positions are linked to the location of Io in the plasma torus. We also know that these spots experience brightness variations from minutes to hours. The Io footprint brightness varies over hours with the longitude of Io in the Jovian magnetic field (System III longitude) but until recently, huge gaps existed in the longitude coverage. Part of these gaps has now been filled during the latest HST imaging campaign and a more complete spot brightness versus Io System III longitude diagram emerges. Additionally, we compare spot brightness between images obtained a few minutes apart but from opposite hemispheres. Based on images gathered from 1997 to 2007 with the STIS and the ACS cameras, we also show that the footprint morphology and the spots brightness, including their relative brightness, can vary significantly from one year to another. Finally, we discuss the brightness variations from hours to years in terms of plasma torus density and position of Io in the plasma torus as well as in Jovian magnetic field. [less ▲]

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See detailRecent results from HST and ground-based observations of Saturn's aurora
Grodent, Denis ULg; Stallard, T.; Gérard, Jean-Claude ULg et al

Conference (2008, December 01)

Current observations of Saturn's aurora performed from Earth-orbit with HST and ground based instruments more than complement the in situ measurements obtained by the Cassini spacecraft. These remote ... [more ▼]

Current observations of Saturn's aurora performed from Earth-orbit with HST and ground based instruments more than complement the in situ measurements obtained by the Cassini spacecraft. These remote observations focus on two spectral windows revealing different facets of the same auroral phenomenon. The auroral photons captured in the ultraviolet bandwidth result from direct impact excitation of H and H2 by charged particles accelerated along magnetic field lines, while the thermal infrared emission involves additional steps in order to produce hot H3+ from the auroral energy. Each spectral window presents its own advantages. The high spatial and temporal resolution of the recent UV images obtained with HST make it possible to discriminate auroral sub-structures, such as short lived arcs and spots, and to map them into the magnetosphere where they can be associated with in situ observations. Infrared high resolution spectroscopy and emission-line imaging from ground observatories (IRTF, UKIRT) have more modest spatial resolution; however they recently pinned down emissions barely observed in the UV. Furthermore, they offer a direct measurement of the ion wind velocities in the auroral ionosphere. These ion flow patterns might then be used to untangle the origin of the auroral particles. The complementarity of observations obtained in the UV and IR bandwidths provides a powerful tool to study the auroral mechanisms in the Kronian magnetosphere and the atmospheric response to the auroral input. [less ▲]

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See detailThe variation of different components of Jupiter's auroral emission
Nichols, J.; Clarke, J.; Gérard, Jean-Claude ULg et al

Conference (2008, December 01)

In this paper we use the extensive HST data set obtained over two month-long campaigns in 2007 to determine the long term variability of the different components of Jupiter's auroras. We define three ... [more ▼]

In this paper we use the extensive HST data set obtained over two month-long campaigns in 2007 to determine the long term variability of the different components of Jupiter's auroras. We define three regions on the planet's disc, i.e. the main oval, the low latitude, and high latitude auroras, and extract the UV auroral power emitted therefrom. The high latitude region was also further divided into the polar inner and polar outer regions. We discuss the temporal variation of these parameters with reference to the auroral morphology and estimated solar wind conditions projected to Jupiter's orbit from data obtained at Earth orbit. We show that the auroral morphology was very different between the first and second campaigns. In the first campaign the emitted power originated mainly from the main oval and the high latitude regions, which roughly correlated, and exhibited enhancements that are suggested to be associated with compression regions. In the second campaign the high latitude and main oval auroras were generally dimmer overall and less variable, while the low latitude region was populated with bright, patchy emission. We show that a particular auroral morphology is probably associated specifically with compression regions, i.e. over longitudes greater than approx. 180 degrees the main oval is bright and located approx. 1 degree poleward of its previous location, while over smaller longitudes the main oval is not bright or well defined. Instead there is bright emission originating from the contiguous poleward region in the afternoon/dusk sector where bright, sometimes multiple arcs form. It remains unclear, however, whether this state is a response to the initial shock or some other event within the rapidly-varying compression regions. We also show that the dawn storm events, typically associated with intense dawn side main oval auroras also result in the brightening of the high latitude auroras, even to the very highest latitude components, which presumably map to a very different region of the magnetosphere. However, apart from the dawn storms and bright poleward arcs in the afternoon/dusk sector, the power emitted from the poleward auroras is generally uncorrelated with that of the main oval. [less ▲]

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See detailThe Ultraviolet Spectrograph (UVS) on Juno
Gladstone, G. R.; Persyn, S.; Eterno, J. et al

Conference (2008, December 01)

Juno, a NASA New Frontiers mission, plans for launch in August 2011, a 5-year cruise (including a flyby of Earth in October 2013 for a gravity boost), and 14 months around Jupiter after arriving in August ... [more ▼]

Juno, a NASA New Frontiers mission, plans for launch in August 2011, a 5-year cruise (including a flyby of Earth in October 2013 for a gravity boost), and 14 months around Jupiter after arriving in August 2016. The spinning (2 RPM), solar-powered Juno will study Jupiter from a highly elliptical orbit, in which the spacecraft (for about 6 hours once every 11 days) dives down over the north pole, skims the outermost atmosphere, and rises back up over the south pole. This orbit allows Juno avoid most of the intense particle radiation surrounding the planet and provides an excellent platform for investigating Jupiter's polar magnetosphere. Part of the exploration of Jupiter's polar magnetosphere will involve remote sensing of the far-ultraviolet H and H2 auroral emissions, plus gases such as methane and acetylene which add their absorption signature to the H2 emissions. This hydrocarbon absorption can be used to estimate the energy of the precipitating electrons; since more energetic electrons penetrate deeper into the atmosphere and the UV emissions they produce will show more absorption. Juno will carry an Ultraviolet Spectrograph (UVS) to make spectral images of Jupiter's aurora. UVS is a UV imaging spectrograph sensitive to both extreme and far ultraviolet emissions in the 70-205~nm range that will characterize the morphology and spectral nature of Jupiter's auroral emissions. Juno UVS consists of two separate sections: a dedicated telescope/spectrograph assembly and a vault electronics box. The telescope/spectrograph assembly contains a telescope which feeds a 0.15-m Rowland circle spectrograph. The telescope has an input aperture 40à 40~mm2 and uses an off-axis parabolic primary mirror. A flat scan mirror situated at the front end of the telescope (used to target specific auroral features at up to ±30° perpendicular to the Juno spin plane) directs incoming light to the primary. The light is then focused onto the spectrograph entrance slit, which has a 'dog- bone' shape 6° long, in three 2° sections of 0.2°, 0.05°, and 0.2° width (projected onto the sky). Light entering the slit is dispersed by a toroidal grating which focuses the UV bandpass onto a curved microchannel plate (MCP) cross delay line (XDL) detector with a solar blind UV- sensitive CsI photocathode, which makes up the instrument's focal plane. Tantalum shielding surrounds the detector assembly to protect the detector and the adjacent detector electronics from high-energy electrons. The main electronics box is located in the Juno vault. Inside are two redundant high-voltage power supplies (HVPS), two redundant low-voltage power supplies, the command and data handling (C&DH) electronics, heater/actuator activation electronics, scan mirror electronics, and event processing electronics. An overview of the UVS design and scientific performance will be presented. [less ▲]

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See detailSaturn Auroral Movies from Cassini UVIS
Pryor, W. R.; Stewart, I.; Esposito, L. et al

Conference (2008, December 01)

Cassini's Ultraviolet Imaging Spectrograph (UVIS) has completed four years of study of Saturn's atmosphere and auroras. Two long slit spectral channels are used to obtain EUV data from 56.3-118.2 nm and ... [more ▼]

Cassini's Ultraviolet Imaging Spectrograph (UVIS) has completed four years of study of Saturn's atmosphere and auroras. Two long slit spectral channels are used to obtain EUV data from 56.3-118.2 nm and FUV data from 111.5-191.3 nm. 64 spatial pixels along each slit are combined with slit motion to construct spectral images of Saturn. Auroral emissions are seen from electron-excited molecular and atomic hydrogen. In 2008 UVIS obtained data with the spacecraft well out of Saturn's ring plane, permitting UVIS to obtain a number of short movies of the rotating auroral structures. In some movies a cusp-like feature is present near noon inside the oval. One movie from 2008 day 201 shows parallel linear features on the day side almost at right angles to the main auroral oval that appear, then lengthen, separate in the middle, and then fade away. The same movie also shows one bright "polar flare" inside the oval. A few of the most recent images were obtained at sufficiently close range that 2 spacecraft slews were needed to completely cover the oval. These images provide almost 100 pixels of information across the oval and clearly show multiple arcs of emission on the main oval and scattered emissions inside the oval. We will discuss these features, their locations, and possible interpretations. [less ▲]

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See detailThe Degree of Correlation of Jovian and Saturnian Auroral Emissions With Solar Wind Conditions
Clarke, J. T.; Nichols, J.; Gérard, Jean-Claude ULg et al

Conference (2008, December 01)

While the terrestrial aurorae are known to be driven primarily by the interaction of the Earth's magnetosphere with the solar wind, auroral emissions on Jupiter and Saturn are thought to be driven ... [more ▼]

While the terrestrial aurorae are known to be driven primarily by the interaction of the Earth's magnetosphere with the solar wind, auroral emissions on Jupiter and Saturn are thought to be driven primarily by internal processes, with the main energy source being the planets' rapid rotation. Limited evidence has suggested there might be some influence of the solar wind on Jupiter's aurorae, and indicated that auroral storms on Saturn can occur at times of solar wind pressure increases. To investigate in detail the dependence of auroral processes on solar wind conditions, a large campaign of observations of these planets has been undertaken using the Hubble Space Telescope, in association with measurements from planetary spacecraft and solar wind conditions both propagated from one AU and measured near each planet. The data indicate a consistent brightening of both the auroral emissions and Saturn Kilometric Radiation (SKR) at Saturn close in time to the arrival of solar wind shocks and pressure increases, consistent with a direct physical relationship between Saturnian auroral processes and solar wind conditions. This correlation has been strengthened by the final campaign observations in Feb. 2008. At Jupiter the situation is less clear, with increases in total auroral power seen near the arrival of solar wind forward shocks, while little increase has been observed near reverse shocks. In addition, auroral dawn storms have been observed when there was little change in solar wind conditions. The data are consistent with some solar wind influence on some Jovian auroral processes, while the auroral activity also varies independently of the solar wind. This extensive data set will serve to constrain theoretical models for the interaction of the solar wind with the magnetospheres of Jupiter and Saturn. [less ▲]

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See detailCoordinated measurements of auroral processes at Saturn from the Cassini spacecraft and HST
Mitchell, D. G.; Kurth, William; Hospodarsky, G. B. et al

Conference (2008, December 01)

One of the primary Cassini mission objectives at Saturn is to characterize Saturn's aurora-its spatial morphology, associated particle energization, radio wave generation, and magnetospheric currents ... [more ▼]

One of the primary Cassini mission objectives at Saturn is to characterize Saturn's aurora-its spatial morphology, associated particle energization, radio wave generation, and magnetospheric currents, relationship with solar wind pressure and magnetic field, and its large scale mapping to the magnetosphere. By design, the Cassini orbital tour included high inclination and low periapsis orbits late in the prime mission specifically to address many of these topics. In this presentation, we will provide a snapshot of the current state of our investigation into the relationship between magnetospheric measurements of particles and fields, and the aurora. For in situ data, we will show measurements of upward traveling light ion conics (~30 keV to 200 keV), often accompanied by electron beams (<20 keV to ~1 MeV) and enhanced broadband noise (10 Hz to a few kHz), throughout the outer magnetosphere on field lines that nominally map from well into the polar cap (dipole L > 50) to well into the closed field region (dipole L < 10). Sometimes the particle phenomena and the broadband noise occur in pulses of roughly five-minute duration, separated by tens of minutes. At other times they are relatively steady over an hour or more. Magnetic signatures associated with some of the pulsed events are consistent with field aligned current structures. Correlative observations of solar wind (Cassini) and aurora (HST) have established a strong relationship between solar wind pressure and auroral activity (brightness) (Crary et al., Nature, 2005; Clarke et al., JGR, 2008). A similar correspondence between bright auroral arcs and ring current ion acceleration will be shown here. So while some auroral forms seem to be associated with the open/closed field boundary (i.e. in the cusp-Bunce et al., JGR, 2008), we also demonstrate that under some magnetospheric conditions for which protons and oxygen ions are accelerated once per Saturn magnetosphere rotation at a preferred local time between midnight and dawn, simultaneous auroral observations by the HST reveal a close correlation between these dynamical magnetospheric events and dawn-side transient auroral brightenings. Likewise, many of the recurrent energetic neutral atom enhancements coincide closely with bursts of Saturn kilometric radiation, again suggesting a linkage with high latitude auroral processes. Finally, we will show some intriguing results of auroral movie sequences from the Cassini UVIS instrument with corresponding ring current movies from the Magnetospheric Imaging Instrument Ion and Neutral Camera (MIMI/INCA). [less ▲]

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See detailModelling Uncertainties in the Climate of the Last Millennium: the ASTER Project
Loutre, M.; Mouchet, Anne ULg; Fichefet, T. et al

Poster (2008, December 01)

The LOVECLIM model (Driesschaert et al., 2007; Goosse et al., 2007) is used to simulate the climate of the last millennium with several 'climate' parameter sets yielding different sensitivities of the ... [more ▼]

The LOVECLIM model (Driesschaert et al., 2007; Goosse et al., 2007) is used to simulate the climate of the last millennium with several 'climate' parameter sets yielding different sensitivities of the climate and the carbon cycle model. The purpose of these simulations is twofold. We intend to assess first the role of the carbon cycle on the climate, and second, the ability of the different selected parameter sets to drive the model within the range of the observed climate, and further to assess the uncertainty related to these parameters. The high frequency variability of the forcings is taken into account. For each set of parameters, LOVECLIM is driven by the natural evolution of insolation, solar irradiance and stratospheric aerosol concentrations due to volcanic activity as well as by changes caused by human activities such as deforestation, CO2 emission or concentration changes, changes in concentrations of greenhouse gases other than CO2 (including ozone) and in sulphate aerosol load. Several transient experiments are conducted for each parameter set. A first transient simulation (CONC) is forced with reconstructed atmospheric CO2 concentration. In the next two simulations, the emissions of carbon are taken into account, the model computing the corresponding atmospheric CO2 concentration. First (EMIS), the emissions due both to the land use changes and the fossil fuel burning are provided. Second (EFOR), only the emissions from fossil fuel burning are provided in addition to the vegetation change related to deforestation. The Northern Hemisphere annual mean temperatures simulated by the model according to the different parameter sets and carbon cycle sensitivities do not show striking differences. The general pattern shows slightly warmer conditions in the early part of the simulation and cooler ones during the Little Ice Age. At last, the global warming of the last century is also clearly simulated. The response of the carbon cycle to the evolution of forcings over the last millennium does not differ much among experiments although there is a much larger spread when considering different emission scenarios (e.g. EFOR and EMIS). Sensitivity tests to the amplitude of the variation of the total solar irradiance (TSI) are performed; a very first quick look at the simulations does not show significant differences in the pattern of the simulated climate in response to modification in the TSI amplitude. Further analysis must be conducted. Climate response to different schemes of deforestation will also be presented. Driesschaert E., Fichefet T., Goosse H., Huybrechts P., Janssens I., Mouchet A., Munhoven G., Brovkin V., and Weber S. L., 2007. Modelling the influence of Greenland ice sheet melting on the Atlantic meridional overturning circulation during the next millennia. Geophys. Res. Lett., 34:L1070, 2007. Goosse H., Driesschaert E., Fichefet T., and Loutre M.F., 2007. Information on the early Holocene climate constrains the summer sea ice projections for the 21st century Clim. Past 3, 683-692. [less ▲]

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See detailElaboration of Magnetic Nanodots by Nanosphere Lithography : a Computerized Method for Order Quantification
Colson, Pierre ULg; Cloots, Rudi ULg; Henrist, Catherine ULg

Conference (2008, December 01)

Nanosphere lithography (NSL) is an ideal inexpensive fabrication tool for producing regular, nearly homogenous arrays of nanoparticules with different sizes. There are many different methods for the ... [more ▼]

Nanosphere lithography (NSL) is an ideal inexpensive fabrication tool for producing regular, nearly homogenous arrays of nanoparticules with different sizes. There are many different methods for the fabrication of the latex monolayer based on electrophoresis, the controlled evaporation of a solvent from the suspension containing latex particles, spincoating etc… We focused our work on this last method. The main problem with formation of 2D latex monolayers is that there are always a high number of different structural defects such as: point defects (vacancies), line defects (dislocations) and also many disordered areas. The influence of the different spincoating parameters on the amount of defects was determined by image analysis of SEM micrographies from the different samples. FePt and Co films were deposited onto quartz substrates through the polystryrene monolayers by magnetron sputtering. The nanopsheres were removed by sonication in toluene. Post-deposition annealing treatment was performed under reductive atmosphere for the FePt nanodots in order to transform the as-deposited chemically disoredered face-centered cubic (fcc) structure into the chemically ordered face-centered tetragonal (fct) phase (L10-phase). DRX , SEM and MFM analysis were performed on the different samples. [less ▲]

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See detailL'audit social. Evaluez les risques sociaux de votre entreprise !
Robert, Frédéric; Maréchal, Benoît ULg

Conference (2008, December 01)

This seminar introduce to the practice of the social audit with regard to compagnies. On basis of a list of social risks with regard to labour law and social security law, the Authors illustrated how ... [more ▼]

This seminar introduce to the practice of the social audit with regard to compagnies. On basis of a list of social risks with regard to labour law and social security law, the Authors illustrated how these risks could be examined and evaluated in the case of a social audit of the company. [less ▲]

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See detailImpact of medication non-compliance and non-persistence on pharmacoeconomic evaluations in osteoporosis
Hiligsmann, Mickaël ULg; Rabenda, Véronique ULg; Gathon, Henry-Jean ULg et al

in Osteoporosis International (2008, December), 19(S2), 282

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See detailSignes de conflit d’intentions dans un syndrome de déconnexion calleuse : cas J.B.
VINCENT, Eric ULg; DELRUE, Gaël ULg; SALMON, Eric ULg et al

Poster (2008, December)

Presentation of a patient showing multiple symptoms of a callosal disconnection.

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See detailLindane et goudron dans les shampoings: quelle toxicité ?
Theunis, Laetitia ULg

Conference (2008, December)

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See detailPerturbation finite element method for the analysis of earthing systems with vertical and horizontal rods
V Sabariego, Ruth ULg; Ferreira da Luz, Mauricio V.; Nzuru Nsekere, Jean-Pierre et al

in Proceedings of the 6ème Conférence Européenne sur les Méthodes Numériques en Electromagnétisme (NUMELEC2008) (2008, December)

This paper deals with the electrokinetic modeling of earthing systems by means of a sub-domain perturbation finite element technique. An axisymmetric problem is solved for each single grounding rod or ... [more ▼]

This paper deals with the electrokinetic modeling of earthing systems by means of a sub-domain perturbation finite element technique. An axisymmetric problem is solved for each single grounding rod or cable. Its solution must then be corrected by taking into account the influence of the other rods and cables. The electric scalar potential is transferred from one problem to the other through projections between meshes. An inherently 3D problem can thus be solved as a succession of 2D sub-problems, which significantly speeds up the solution and enables to tackle complicated grounding systems. [less ▲]

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See detailLBG-SQUARE - Fault Tolerant, Locality-Aware Co-allocation in P2P Grids
Dethier, Gérard ULg; Briquet, Cyril ULg; Marchot, Pierre ULg et al

in Huang, Zhiyi; Xu, Zhiwei; Rountree, Nathan (Eds.) et al Ninth International Conference On Parallel And Distributed Computing, Applications And Technologies : PDCAT 2008 (2008, December)

In this paper, the deployment and execution of Iterative Stencil applications on a P2P Grid middleware are investigated. So-called Iterative Stencil applications are composed of sets of heavily ... [more ▼]

In this paper, the deployment and execution of Iterative Stencil applications on a P2P Grid middleware are investigated. So-called Iterative Stencil applications are composed of sets of heavily-communicating, long-running Tasks. They thus require co-allocation of multiple reliable resources for extended periods of time. P2P Grids are totally decentralized and provide on-demand, transparent access to edge resources, e.g. Internet-connected, non-dedicated desktop computers. A P2P Grid has the potential to provide access to a large number of resources at the fraction of the cost of a dedicated cluster. However, edge resources are heterogeneous in performance and intrinsically unreliable: Task execution failures are common due to resource preemption or resource failure. Furthermore, P2P Grid schedulers usually target sets of independent computational Tasks, i.e. so-called Bags of Tasks applications. It is therefore not trivial to deploy and run an Iterative Stencil application on a P2P Grid. Checkpointing is a common fault-tolerance mechanism in High Performance Distributed Computing, often based on a centralized architecture. Locality-aware co-allocation in P2P Grids has been recently investigated. Checkpointing and locality-aware co-allocation yet have to be integrated in P2P Grids. We propose to provide co-allocation through an existing middleware-level Bag of Tasks scheduling mechanism. We also introduce a layer of fault-tolerance for the Iterative Stencils that relies on a scalable, application-level, P2P checkpointing mechanism. Finally, LBG-SQUARE is described. This software results from the combination of a specific Iterative Stencil application (a Computational Fluid Dynamics simulation software called LaBoGrid) with a P2P Grid middleware (Lightweight Bartering Grid). [less ▲]

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See detailCost-utility of calcium and vitamin D supplementation in the treatment of postmenopausal osteoporotic women
Hiligsmann, Mickaël ULg; Bruyère, Olivier ULg; Ethgen, Olivier ULg et al

in Osteoporosis International (2008, December), 19(S2), 363

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See detailModélisation numérique des courants et tensions de contact dans des habitations
Lorphèvre, Raoul; Dular, Patrick ULg; V Sabariego, Ruth ULg et al

in Actes de 6ème conférence européenne sur les méthodes numériques en électromagnétisme (NUMELEC 2008) (2008, December)

Un modèle d’installation électrique d’habitation avec une ligne à haute tension est développé avec la méthode "Partial Element Equivalent" (PEEC). Cette étude a pour but de déterminer l’existence des ... [more ▼]

Un modèle d’installation électrique d’habitation avec une ligne à haute tension est développé avec la méthode "Partial Element Equivalent" (PEEC). Cette étude a pour but de déterminer l’existence des courants et tensions induits dans une maison et d’évaluer leur amplitude. Ensuite, nous caractérisons l’influence d’un réseau d’habitations et du type de prise de terre sur ceux-ci. Cette partie du travail nous permet d’obtenir un ensemble de facteurs influençant le niveau des courants induits. Ce papier montre qu’il est possible de déterminer des configurations pour minimiser ces courants dans un réseau d’habitations. [less ▲]

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See detailLake Hazar: a potential high-resolution 150 ka record of climate and tectonic interactions in Anatolia.
Boes, Xavier; Garcia, D; Avsar, U et al

in EOS : Transactions, American Geophysical Union (2008, December), 89(53)(Fall Meet. Suppl.), 21-1942

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See detailTowards an Improved Single-Frequency Ionospheric Correction: Focus on Mid-Latitudes
Bidaine, Benoît ULg; Warnant, René ULg

in 4th ESA Workshop on Satellite Navigation User Equipment Technologies NAVITEC (2008, December)

The modelling of the Total Electron Content (TEC) plays an important role in global satellite navigation systems (GNSS) accuracy, especially for single frequency receivers, the most common ones ... [more ▼]

The modelling of the Total Electron Content (TEC) plays an important role in global satellite navigation systems (GNSS) accuracy, especially for single frequency receivers, the most common ones constituting the mass market. For the latter and in the framework of Galileo, the NeQuick model has been chosen for correcting the ionospheric error contribution. It has been designed to calculate the electron density at a given point of the ionosphere according to the time conditions and the solar activity. This electron density can be integrated along the path from the receiver to the considered satellite to provide the TEC. For Galileo, a parameter Az (“effective ionisation level”) will be provided to the model as solar activity information and will be daily updated by the ground stations. In order to reach the ionosphere error correction level objective (70% or 20 TECu whichever is larger), the model itself as well as its use for Galileo are investigated. Different situations have to be considered: different latitude regions (space conditions), different hours, seasons and years (time conditions) and specific phenomena appearance (magnetic storms, Travelling Ionospheric Disturbances – TIDs). In addition the results can be compared to different data sets among which GPS slant or vertical TEC (sTEC or vTEC) measurements, Global Ionospheric Maps, ionosonde profiles, topside soundings but also other ionosphere models results such as IRI. In our comparison process, we take benefit of various ionosphere data from several European stations (Chilton in UK, Dourbes in Belgium, El Arenosillo and Roquetes in Spain, Pruhonice in Czech Republic) where ionosonde and GPS TEC data are available for different solar activity levels. These data allow us to study NeQuick representation of the ionosphere at mid-latitudes. We investigate the difference between GPS-derived vTEC and corresponding values from NeQuick for the latest years (between solar maximum in 2000 and minimum in 2007) in order to observe the temporal dependencies towards Universal Time, season and solar activity. On the one hand, we use ionosonde data to constrain the model so that we can concentrate on its formulation of the profile only. We especially highlight the improvements from the latest (second) version of NeQuick and show the critical importance of the topside formulation. On the other hand, we analyse the model residual errors for the same situations computing vTEC through the Galileo algorithm. [less ▲]

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See detailInternal dynamics from asteroseismology for two sdB pulsators in close binary systems
Van Grootel, Valérie ULg; Charpinet, Stéphane; Fontaine, Gilles et al

in Communications in Asteroseismology (2008, December), 157

Since their discovery eleven years ago, short-period pulsating sdB stars have proved their potential for quantitative asteroseismological studies. We have recently updated our astero- seismic diagnostic ... [more ▼]

Since their discovery eleven years ago, short-period pulsating sdB stars have proved their potential for quantitative asteroseismological studies. We have recently updated our astero- seismic diagnostic tools in order to incorporate the effects of stellar rotation on pulsations, assuming various internal rotation laws. It is possible, with these new tools, to determine the internal rotation profile of two short-period pulsating sdB stars residing in close binary systems, namely Feige 48 and PG 1336 -018. They exhibit orbital periods of 9.024 h and 2.424 h respectively, as measured from spectroscopy. For the two stars, we show that spin-orbit synchronism is reached from the surface down to ˜ 0.22 R∗ and 0.55 RxE2x88x97 , respectively. The rotation of deeper layers cannot be inferred with the type of modes p-modes observed in short-period pulsating sdB stars. These results can potentially provide new elements to test tidal friction theories, particularly the angular momentum transport, in close binary systems. [less ▲]

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See detailA Self-Organized clustering scheme for overlay networks
Cantin, François ULg; Gueye, Cheikh Ahmadou Bamba ULg; Kaafar, Mohamed Ali ULg et al

in Lecture Notes in Computer Science (2008, December), 5343

Hierarchical approaches, where nodes are clustered based on their network distances, have been shown to allow for robust and scalable topology-aware overlays. Moreover, recent research works have shown ... [more ▼]

Hierarchical approaches, where nodes are clustered based on their network distances, have been shown to allow for robust and scalable topology-aware overlays. Moreover, recent research works have shown that cluster-based deployments of Internet Coordinates Systems (ICS), where nodes estimate both intra-cluster and inter-cluster distances, do mitigate the impact of Triangle Inequality Violations (TIVs) on the distance predictions, and hence offer more accurate internet latency estimations. To allow the construction of such useful clusters we propose a self-organized distributed clustering scheme. For better scalability and efficiency, our algorithm uses the coordinates of a subset of nodes, known by running an ICS system, as first approximations of node positions. We designed and evaluated two variants of this algorithm. The first one, based on some cooperation among nodes, aims at reducing the expected time to construct clusters. The second variant, where nodes are selfish, aims at reducing the induced communication overhead. [less ▲]

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See detailDefining additional stratigraphy in paleosismic trenches by 2D logging of magnetic susceptibility. A paleoseismic investigation near Lake Ladik, North Anatolian Fault, Turkey.
Fraser, J; Hubert, Aurelia ULg; Vanneste, K. et al

in EOS : Transactions, American Geophysical Union (2008, December), 89(53)(Fall Meet. Suppl.), 21-1942

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See detailEnjeux et conditions de l'enseignement des langues dans les universités
Defays, Jean-Marc ULg

Conference (2008, December)

Detailed reference viewed: 11 (2 ULg)
See detailDevelopment of products for GNSS users at the Belgian Solar-Terrestrial Centre of Excellence
Warnant, René ULg; Lejeune, Sandrine; Stankov, Stanimir et al

Conference (2008, December)

Detailed reference viewed: 121 (22 ULg)
See detailIsothermal titration calorimetry as a tool for improving enzymatic lignocellulose hydrolysis
Razafindralambo, Hary ULg; Boquel, Pascal; Jacquet, Nicolas ULg et al

Conference (2008, December)

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See detailMode identification in rapidly pulsating subdwarf B stars from monochromatic amplitude- and phase variations
Randall, Suzanna K.; Van Grootel, Valérie ULg; Fontaine, Gilles et al

in Communications in Asteroseismology (2008, December), 157

We present a mid-term report on a project aimed at partially identifying the main modes of pulsation in the rapidly pulsating subdwarf B star PG 1047+003. Using the unique HIT-MS mode on FORS2 at the VLT ... [more ▼]

We present a mid-term report on a project aimed at partially identifying the main modes of pulsation in the rapidly pulsating subdwarf B star PG 1047+003. Using the unique HIT-MS mode on FORS2 at the VLT we obtained ˜3000 spectra spread over 4 consecutive half-nights with a typical sampling rate of 20 s. These will be used to extract monochromatic pulsation amplitudes and phases that can be fit to model predictions in order to determine the degree ℓ of the mode in question. [less ▲]

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See detailCoordination on Lie groups
Sarlette, Alain ULg; Bonnabel, Silvère; Sepulchre, Rodolphe ULg

in Proceedings of the 47th IEEE Conference on Decision and Control (2008, December)

This paper studies the coordinated motion of a group of agents evolving on a Lie group. Left- or right-invariance with respect to the absolute position on the group lead to two different characterizations ... [more ▼]

This paper studies the coordinated motion of a group of agents evolving on a Lie group. Left- or right-invariance with respect to the absolute position on the group lead to two different characterizations of relative positions and two associated definitions of coordination (fixed relative positions). Conditions for each type of coordination are derived in the associated Lie algebra. This allows to formulate the coordination problem on Lie groups as consensus in a vector space. Total coordination occurs when both types of coordination hold simultaneously. The discussion in this paper provides a common geometric framework for previously published coordination control laws on SO(3), SE(2) and SE(3). The theory is illustrated on the group of planar rigid motion SE(2). [less ▲]

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See detailDéveloppement d’un outil de prédiction de la probabilité de réussite à l’insémination chez la vache laitière à partir des données du Contrôle Laitier
Laloux, Laurent; Bastin, Catherine ULg; Glorieux, Géry et al

in 15ème Rencontres Recherches Ruminants, Paris, les 3 et 4 décembre 2008 (2008, December)

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See detailOverlay Routing using Coordinate Systems
Cantin, François ULg; Gueye, Cheikh Ahmadou Bamba ULg; Kaafar, Mohamed Ali ULg et al

Poster (2008, December)

We address the problem of finding indirect overlay paths that reduce the latency between pairs of nodes in an overlay. To this end we propose to rely on an Internet Coordinate System (ICS), namely Vivaldi ... [more ▼]

We address the problem of finding indirect overlay paths that reduce the latency between pairs of nodes in an overlay. To this end we propose to rely on an Internet Coordinate System (ICS), namely Vivaldi, to estimate RTTs and help find these interesting detours. We define two initial criteria to illustrate our approach and assess their true/false positive rates. [less ▲]

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See detailCarbon Cycle and Climate Sensitivity in an Earth System Model
Mouchet, Anne ULg; Loutre, M.; Fichefet, T. et al

Poster (2008, December)

The sensitivity of the potential feedbacks between climate and biogeochemical cycles (BGC) is adressed with the help of LOVECLIM, a global three-dimensional Earth system model of intermediate complexity ... [more ▼]

The sensitivity of the potential feedbacks between climate and biogeochemical cycles (BGC) is adressed with the help of LOVECLIM, a global three-dimensional Earth system model of intermediate complexity. Key physical or biogeochemical parameters of LOVECLIM are varied within their range of uncertainty in order to provide an ensemble of parameter sets resulting in contrasted climate and global carbon cycle sensitivities. The selected climate parameter sets lead to a climate sensitivity ranging from 2 to 4°C and a reduction of the Atlantic meridional overturning circulation (MOC) ranging from 20 to 60% after 1 kyr in response to identical external forcings. The key parameters for the carbon cycle were chosen among those with the largest impact on the marine biogeochemical cycle and on the response of atmospheric CO2 to emission scenario. We then analyze the results of freshwater hosing experiments in which both the climate parameters and the BGC parameters are modified. These experiments allow to examine the impact of changes in climate sensitivity and of MOC reduction over the biogeochemical cycles as well as to assess the potential feedback from the carbon cycle onto the climate. A decreasing MOC directly impacts the ocean biogeochemistry. Most of the model setups show a decline in export production although some parameter sets yield reorganisation of the large scale ocean circulation, which leads to different behaviour of the ocean biogeochemistry. The atmospheric carbon is also affected by a decrease of the MOC. While most parameter sets cause a modest increase in atmospheric CO2, consecutive to the decrease of the continental vegetation, some model versions exhibit an amplification of the atmospheric CO2 response to the forcing. The mechanisms leading to the different responses for the different parameter sets are examined and discussed. [less ▲]

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See detailSedimentological fingerprints of recent earthquakes in lake sediments: A case study on the North Anatolian Fault (NAF), Turkey
Avsar, Ulas; Boes, X; Hubert, Aurelia ULg et al

in EOS : Transactions, American Geophysical Union (2008, December), 89(53)(Fall Meet. Suppl.), 21-1919

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See detailLes cultes isiaques à Argos. Du mythe à l'archéologie
Veymiers, Richard ULg

Conference (2008, November 29)

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See detailCe que les NAC nous apprennent sur la médecine factuelle
Vandeweerd, Jean-Michel; Vandenput, Sandrina ULg

Conference (2008, November 28)

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See detailMonitoring the motion of a macrocycle in a bistable molecular shuttles
Lussis, Perrine ULg; Fustin, Charles-André; Bertocco, Andrea et al

Poster (2008, November 28)

In recent years it has been proved possible to design synthetic molecular systems in which positional displacements of sub-molecular components occur upon the application of external stimuli.[1-4] Through ... [more ▼]

In recent years it has been proved possible to design synthetic molecular systems in which positional displacements of sub-molecular components occur upon the application of external stimuli.[1-4] Through the pioneering work of Stoddart, Sauvage and others[1-3] it has become clear that the remarkable ability of rotaxanes to change the relative positions of their interlocked components in response to various external stimuli (light, electrons, heat, pH, nature of the environment) should one day find practical uses. However, truly functional systems based on synthetic molecular machines are still to be produced. Some key questions remain unanswered: What are the structural features necessary for molecules to convert this controlled motion into useful function? At what level (single molecule, nanoscopic, microscopic, macroscopic) can this be done? Can we address and utilize the induced-motion in a single molecular machine? To answer those questions we are advocating the use of molecular machines coupled to a polymeric scaffold. We are convinced that this is an efficient route to translate the sub-molecular motion into a useful response that can be exploited to perform physical tasks. Molecular machines with mechanically interlocked architectures are particularly suited for these sorts of applications because, they permit the controlled, large amplitude, movement and positioning of one mechanically interlocked component with respect to another. Among these architectures, rotaxanes -i.e. molecules consisting of a macrocycle threaded on a linear molecule capped with bulky end stoppers- are a particularly promising kind of synthetic molecular 'shuttles'. Our objective is to demonstrate the feasibility of transducing the controlled translational motion of the ring in a rotaxane into mechanical work using AFM-based single molecule force spectroscopy as a mechanical device.[5] For that purpose, a bistable hydrogen-bonded rotaxane with one fumaramide and one succinic amide ester station was synthesized. The equilibrium distribution of the ring between the two stations is in favour of the fumaramide station (>95%).[6] We have attached a poly-ethylene oxide (PEO) chain to the ring by 'click chemistry' and the resulting rotaxane-polymer compound was grafted onto gold substrates. We then fished the PEO chain with an AFM tip. The applied force exerted on the ring when pulling on the polymer chain causes the H bonds linking the ring to the fumaramide station to break, but when trying to move away the ring, it shuttles back to its station in the opposite direction of the pulling force. We estimated that the work done by the ring against the pulling force was about 3 kcal mole-1. This result is in good agreement with the theoretical value predicted by Altieri et. al.[6] [1] Special Issue on Molecular Machines, Acc. Chem. Res. 2001, 34, p. 409-522. [2] V. Balzani, A. Credi, M. Venturi, Molecular Devices and Machines – A Journey into the Nano World, Wiley-VCH, Weinheim, Germany, 2003. [3] E R Kay, D A Leigh and F Zerbetto, Angew. Chem. Int. Ed. 2007, 46, 72. [4] a) V Bermudez, N Capron, T Gase, F G Gatti, F Kajzar, D A Leigh, F Zerbetto and S Zhang, Nature, 2000, 406, 608. b) A M Brouwer, C Frochot, F G Gatti, D A Leigh, L Mottier, F Paolucci, S Roffia, G W H Wurpel, Science , 2001, 291, 2124. c) D A Leigh, J K Y Wong, F Dehez and F Zerbetto, Nature, 2003, 424, 174. d) J V Hernandez, E R Kay and D A Leigh, Science, 2004, 306, 153. e) E R Kay and D A Leigh, Nature, 2006, 440, 286. f) V Serreli, C-F Lee, E R Kay and D A Leigh, Nature, 2007, 445, 523. [5] T. Hugel, N. B. Holland, A. Cattani, L. Moroder, M. Seitz, H. E. Gaub, Science 2002, 296, 1103. [6] A. Altieri, G. Bottari, F. Dehez, D A Leigh, J.K.Y Wong, F Zerbetto, Angew. Chem. Int. Ed. 2003, 42, 2296. [less ▲]

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See detailPreparation and characterization of thermoresponsive iron nanoparticles for biomedical applications
Sibret, Pierre ULg; Aqil, Abdelhafid ULg; Gohy, Jean-François et al

Poster (2008, November 28)

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See detailElectrografting of thermo-responsive polymer films on conducting surfaces
Gabriel, Sabine; Stach, M.; Confortini, O. et al

Poster (2008, November 28)

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See detailLe Childhood Anxiety Sensitivity Index-Revised (CASI-R) : Etude de validation.
Stassart, Céline ULg; Depauw, Brigitte; Delvaux, Muriel ULg et al

Poster (2008, November 28)

La sensibilité à l'anxiété est la peur des sensations corporelles liées à l’anxiété, qui proviendrait de croyances que ces sensations ont des conséquences somatiques, psychologiques ou sociales néfastes ... [more ▼]

La sensibilité à l'anxiété est la peur des sensations corporelles liées à l’anxiété, qui proviendrait de croyances que ces sensations ont des conséquences somatiques, psychologiques ou sociales néfastes. Ce concept a été très peu exploré dans le contexte infantile. L’AS étant considérée comme un facteur de risque dans le développement et le maintien des troubles anxieux, ceci montre l’intérêt de s’intéresser davantage à l’outil d’évaluation de l’AS dans le contexte infantile, le Childhood Anxiety Sensitivity Index revised. L'objectif de cette étude est de d'évaluer les propriétés psychométriques de la version française de la CASI-R auprès d'un échantillon de 60 enfants âgés de 10 à 11 ans. En ce qui concerne les résultats, la confrontation de la CASI-R aux qualités psychométriques nous fournit des premiers éléments en faveur de l’intérêt clinique et de la pertinence théorique de cet outil dans le contexte infantile. En ce sens, la poursuite de son développement paraît constituer une perspective intéressante. [less ▲]

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See detailDesign of thermoresponsive inorganic nanoparticles
Aqil, Abdelhafid ULg; Jérôme, Christine ULg

Conference (2008, November 28)

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See detailSummary of aim and achievements in Work Package 7 "Functional Coatings"
Jérôme, Christine ULg

Conference (2008, November 28)

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See detailDesign of perfluorinated macroligand for the implementation of atom transfer radical polymerization in supercritical carbon dioxide
Grignard, Bruno ULg; Jérôme, Christine ULg; Calberg, Cédric ULg et al

Conference (2008, November 28)

Due to an increasing need for polymers with well-defined architecture (diblock-, graft-, star-shaped copolymers), molecular weight and/or functional end-groups, the use of controlled radical ... [more ▼]

Due to an increasing need for polymers with well-defined architecture (diblock-, graft-, star-shaped copolymers), molecular weight and/or functional end-groups, the use of controlled radical polymerization (CRP) in scCO2 has started to gain attention. Among all the controlled processes, Atom Transfer Radical Polymerization has emerged as a robust tool for the preparation of polymers with well-defined molecular weight, architecture and chain-end functionality. The goal of the research relies on the development of ATRP of vinyl monomers in scCO2. Perfluorinated polymethacrylate, i.e. poly2,2,2-trifluoroethyl methacrylate (PFMA), was successfully prepared by homogenous ATRP using a polymeric ligand in order to complex the copper catalyst. CO2-soluble poly(2,2,2-trifluoroethylmethacrylate) was also prepared in supercritical CO2 by supported ATRP using a “pseudo-homogeneous” catalyst consisting of copper (I) ligated by macroligand immobilized onto an inorganic support, that results in polymers with well defined molecular weight and low polydispersity. The first efficient dispersion ATRP of methyl methacrylate (MMA) in scCO2 using a fluorinated polymeric ligand that had a dual role, i.e., the complexation of the copper salt and the stabilization of PMMA growing particles was also reported and the concept of dispersion ATRP was extended to the dispersion ATRP of styrene, to the synthesis of diblock copolymers beads using PMMA beads as macroinitiators, leading to (co)polymers with predictable molecular weight and narrow polydispersity. Finally, because both ATRP and alkyne-azide Huisgen’s 1,3-dipolar cycloaddition relies on the use of a Cu(I) catalyst, synthesis of pyrene end-functionalized polymers by simultaneous dispersion ATRP and click reaction was also investigated in supercritical carbon dioxide, leading to the formation of PMMA of well defined characteristics that was collected as fluorescent micropheres. [less ▲]

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See detailTowards Another Summer
Delrez, Marc ULg

Conference (2008, November 28)

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See detailPolymer membrane by electrospinning
Aqil, Abdelhafid ULg; Grignard, Bruno ULg; Croisier, Florence ULg et al

Poster (2008, November 28)

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See detailStimuli responsive nanogels for targeted drug delivery
Jérôme, Christine ULg

Conference (2008, November 28)

Detailed reference viewed: 19 (4 ULg)
See detailNew strategies to prepare melt processable polymer-grafted gold nanoparticles
Alexandre, Michaël ULg; Abetz, Volker; Boschetti-de-Fierro, A. et al

Poster (2008, November 28)

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See detailA Lilliputian lignophyte from the Lower Devonian?
Gerrienne, Philippe ULg; Strullu-Derrien, C.; Steemans, Philippe ULg

Conference (2008, November 27)

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See detailLa figure de la femme dans les opéras de Wolfgang Amadeus Mozart (1756-1791) et de Giuseppe Verdi (1813-1901)
Corswarem, Emilie ULg; Onkelinx, Jean-Marc

Conference (2008, November 26)

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Peer Reviewed
See detailNon rigid stabilization of the spine.
Martin, Didier ULg

Conference (2008, November 21)

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See detailL’enfance comme champ d’intervention politique au Burkina Faso
Wouango, Joséphine ULg

Conference (2008, November 21)

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See detailVenture Creation Intentions and Midlife Crisis
Heuer, Annamaria ULg; Surlemont, Bernard ULg

Conference (2008, November 21)

Aim of the paper This paper aims to analyse the relationship between life stages and the drivers of venture creation intention and, hence, the venture creation. The objective is to analyse the extent to ... [more ▼]

Aim of the paper This paper aims to analyse the relationship between life stages and the drivers of venture creation intention and, hence, the venture creation. The objective is to analyse the extent to which the single-minded focus of most policy measures on early adult population to spur intention is not understating the importance of adapting the approach to specific life stages of the target population. Using different conceptualisations of age biological, psychological, organisational and life span related , we will take here a closer look at the midlife age cluster, centred around the 35th year. Contribution to the literature Numerous studies have applied models based on cognition research to understand entrepreneurial intentions and the factors that impact them (e.g. Autio et al., 2001; Kolvereid, 1996; Krueger, Reilly and Carsrud, 2000; Kristiansen and Indarti, 2004). However, besides a few exceptions, such as Douglas and Shepherd (2002) or Davidsson (1995), most scholars have conducted their studies on university students, due to their advantages as sample, like easier information access and homogeneity of population. Not much attention has been paid to the potential influence of the life-stage factor and its potential impact on policy formulation. Taking a chronological age perspective, Levinson (1986) proposed that there is an “underlying order in human life course”, no matter what occupation or background people have. He conceived life as a sequence of eras, each of them with a specific biopsychosocial character and each of them contributing to the whole life cycle. Major changes of life characteristics occur in the cross-era transition, but also within a life stage. According to this approach, every life stage has tasks to be accomplished (Levinson et al., 1978). From an entrepreneurship perspective, it is especially interesting to introduce this model by taking a closer look at stages of “Early adulthood” (age c. 20-40). “Early adult transition” (age c. 17-22) for instance is characterised by reflections about one’s own place in the world independent from the institutions of youth (parents, school…). It is also about testing one’s initial choices about preferences for the adult life. This is in line with the “impressionable years” hypothesis, which is based on the notion that key attitudes, beliefs, and values are of great plasticity during the early adult years (Sears, 1975; Visser et al., 1998), while suggesting that susceptibility to change in attitude falls sharply after early adult years and stays on a low level for the rest of the life cycle. These attitudes, beliefs and values build an essential pillar of intentions, and are thus relevant for the study of entrepreneurial intentions. A vast quantity of policies trying to foster entrepreneurship usually target the “Early adult transition” cluster, arguing that entrepreneurial intention is created at this stage, even though, it is rather the entrepreneurial attitude that comes into existence at this point. Another remarkable and relevant milestone of Levinson’s life stage development model is linked to the age of c. 29 to 33, called “Thirties transition”, and which is dealing with the evaluation of the accomplishments of the twenties and the adjustments to the adopted life structure. It is a time characterised by instability and change, in which it is to be expected that commitment and satisfaction will remain low: for instance, individuals at this era will express greater intentions to leave their company (Ornstein et al., 1989), and possibly, to create one. This may provide another explanation to why it is observed that the age for new venture creation is around 35 years. Given that entrepreneurial activity does not only depend on the desirability and feasibility of entrepreneurship, but also upon the desirability and feasibility of employment (Kolvereid, 1996b), this could help to explain the increased levels of early-stage entrepreneurship in this age-cluster, and is leading to the following questions: (i) If potential entrepreneurs in their thirties are much more susceptible to change, and considering the aging population and the expected increase of retirement age in the western world the economic importance of “older” entrepreneur’s is likely to increase (Weber, 2004), why then not stimulate them more? (ii) If attitude gets more rigid with age, is applying the same policy strategies to “younger” and “older” potential entrepreneurs really the most efficient approach, or are, this way, policy-makers failing to stimulate a part of the population? (iii) If policy-making is about trying to sell an idea and make the population buy it, why are we then ignoring basic marketing segmentation strategies? In order to provide to our knowledge the first more holistic picture of possible adult development related impacts on entrepreneurial intention, we will proceed in a rather systematic way by choosing different perspectives of aging such as chronological, psychological and organisational, focusing on and around the “midlife” age cluster. Methodology This paper is conceptual in nature, transferring important ideas from adult-development studies to the domain of entrepreneurship. Through our argumentation we will show that an in-depth analysis, in form of comparative studies, of aging-related changes of the factors determining intention is timely. Results To date, there has been only sporadic, short argumentation for aging-related changes of intentional antecedents, such as “organisational age” impacting perceived behavioural control or life-span age impacting how to bear the uncertainty of income from self-employment activity (Shane, 2003). We will provide a more rigorous review of this problematic, and by that hope to contribute to a better understanding of sometimes ambiguous details of study outcomes. Bibliography Aution, E., Keeley, R. H. (2001), ”Entreprenerial intent among students in Scandinavia and in the USA”, Entreprise and Innovation Management Studies, Vol. 2, No. 2, pp.145-160 Davidsson, P. (1995), ”Determinants of entrepreneurial intentions”, Paper prepared for RENT IX Workshop, Piacenza, Italy Douglas, E. J., Dean, A. S. (2002), ”Self-employment as a Career Choice: Attitudes, Entrepreneurial Intentions, and Utility Maximization”, Entrepreneurship: Theory & Practice, Vol. 26, Issue 3, pp. 81-90 Kolvereid, L. (1996), ”Organizational employment versus self-employment: reasons for career choice intentions”, Entrepreneurship: Theory & Practice, Vol. 20, Issue 3, pp. 23-31 Kolvereid, L. (1996b), ”Prediction of Employment Status Choice Intentions”, Entrepreneurship: Theory & Practice, Vol. 21, Issue 1, pp. 47-57 Kristiansen, S., Indarti, N. (2004), ”Entrepreneurial intention among Indonesian and Norwegian students”, Journal of Entreprising Culture, Vol. 12, No. 1, pp. 55-78 Krueger, N. F., Reilly, M. D., Carsrud, A. L. (2000), ”Competing models of entrepreneurial intentions”, Journal of Business Venturing, Vol. 15, Issue 5/6, pp. 411-432 Levinson, D. J., Darrow, C. N., Klein, E. B., Levinson, M. H. and McKee; B. (1978), ”The seasons of a Man’s Life”, Alfred A. Knopf, New York Levinson, D. J. (1986), ”A Conception of Adult Development”, American Psychologist, Vol. 41, No. 1, pp. 3-13 Ornstein, S., Cron, W. L., Slocum, J. W. Jr. (1989), ”Life stage versus career stage: A comparative test of theories of Levinson and Super”, Journal of organizational behaviour, Vol. 10, pp. 117-133 Sears, D. O. (1975), ”Political socialization”, In F.I. Greenstein and N. W. Polsby (Eds.), Handbook of political science, MA: Addison-Wesley Shane, S. (2003), ”A General Theory of Entrepreneurship – The Individual-Opportunity Nexus”, Edward Elgar Publishing, Cheltenham Visser, P. S., Krosnick, J. A. (1998), ”Development of Attitude Strength Over the Life Cycle: Surge and Decline”, Journal of Personality and Social Psychology, Vol. 75, No. 6, pp. 1389-1410 Weber, P., Schaper, M. (2004), ”Understanding the grey entrepreneur”, Journal of Entreprising Culture, Vol. 12, No. 2, pp. 147-164 [less ▲]

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See detailL’architecture des couvents des Annonciades célestes en Belgique et projet de recherche doctoral
Piront, Julie ULg

Conference (2008, November 20)

Cette intervention a livré d'une part les sources, la méthodologie et les résultats de mon mémoire de licence sur l'étude architecturale des couvents "belges" des annonciades célestes et présente d'autre ... [more ▼]

Cette intervention a livré d'une part les sources, la méthodologie et les résultats de mon mémoire de licence sur l'étude architecturale des couvents "belges" des annonciades célestes et présente d'autre part le projet de recherche de ma thèse de doctorat qui envisage l'architecture de l'ensemble des couvents de cet ordre religieux fondés en Europe avant 1800. [less ▲]

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See detailL'office de la Trinité. Liège, Metz, Mayence, Saint-Gall
Close, Florence ULg

Conference (2008, November 20)

L’histoire de l'office de la Trinité a déjà fait couler beaucoup d’encre. Les philologues se sont intéressés à la place du formulaire dans l’histoire des offices versifiés du haut moyen âge, aux sources ... [more ▼]

L’histoire de l'office de la Trinité a déjà fait couler beaucoup d’encre. Les philologues se sont intéressés à la place du formulaire dans l’histoire des offices versifiés du haut moyen âge, aux sources d’inspiration des textes, au principe et à la stratégie d’inspiration ; les musicologues au mode de composition musicale comme au rapport entre les textes chantés et la musique. Par contre, peu a été dit sur la transmission du formulaire – texte et musique confondus – dans l’Eglise occidentale . Cette communication entendait proposer un hypothétique schéma de propagation du formulaire dans la partie orientale de l’ancien empire carolingien, inséré dans une plus large réflexion en cours sur les motifs extra-liturgiques du succès de la première fête votive de l’histoire de la liturgie dans l’Eglise catholique d’Occident. [less ▲]

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See detailDrying of wastewater sludge’s, common practice and challenges
Crine, Michel ULg; Léonard, Angélique ULg

Conference (2008, November 20)

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See detailModelling the Ionosphere over Europe: Investigation of NeQuick Formulation
Bidaine, Benoît ULg; Warnant, René ULg

Poster (2008, November 18)

The modelling of the Total Electron Content (TEC) plays an important role in global satellite navigation systems (GNSS) accuracy, especially for single-frequency receivers, the most common ones ... [more ▼]

The modelling of the Total Electron Content (TEC) plays an important role in global satellite navigation systems (GNSS) accuracy, especially for single-frequency receivers, the most common ones constituting the mass market. For the latter and in the framework of Galileo, the NeQuick model has been chosen for correcting the ionospheric error contribution. It has been designed to calculate the electron density at a given point of the ionosphere according to the time conditions and the solar activity. This electron density can be integrated along the path from the receiver to the considered satellite to provide the TEC. For Galileo, a parameter Az (“effective ionisation level”) will be provided to the model as solar activity information and will be daily updated by the ground stations. Since NeQuick was chosen for Galileo purpose, a new version of the model has been released. It involves simplifications in the representation of the bottomside as well as a unique formula for a key parameter of the topside formulation previously defined through two equations, each one used for six months of the year. Hence we decided to investigate consecutive improvements and remaining weaknesses of this new formulation. To this extent, we take benefit of various ionosphere data from several European stations (Chilton in UK, Dourbes in Belgium, El Arenosillo and Roquetes in Spain, Pruhonice in Czech Republic) where ionosonde and GPS TEC data are available for different solar activity levels. These data allow us to study NeQuick representation of the ionosphere at mid-latitudes. We investigate the difference between GPS-derived vTEC and corresponding values from NeQuick for the latest years (between solar maximum in 2000 and minimum in 2007) in order to observe the temporal dependencies towards Universal Time, season and solar activity. We use ionosonde data to constrain the model so that we can concentrate on its formulation of the profile only. We especially highlight the improvements from the second version of NeQuick and show the critical importance of the topside formulation. [less ▲]

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See detailModelling the Ionosphere over Europe: Investigation of NeQuick Formulation
Bidaine, Benoît ULg; Warnant, René ULg

Conference (2008, November 18)

The modelling of the Total Electron Content (TEC) plays an important role in global satellite navigation systems (GNSS) accuracy, especially for single-frequency receivers, the most common ones ... [more ▼]

The modelling of the Total Electron Content (TEC) plays an important role in global satellite navigation systems (GNSS) accuracy, especially for single-frequency receivers, the most common ones constituting the mass market. For the latter and in the framework of Galileo, the NeQuick model has been chosen for correcting the ionospheric error contribution. It has been designed to calculate the electron density at a given point of the ionosphere according to the time conditions and the solar activity. This electron density can be integrated along the path from the receiver to the considered satellite to provide the TEC. For Galileo, a parameter Az (“effective ionisation level”) will be provided to the model as solar activity information and will be daily updated by the ground stations. Since NeQuick was chosen for Galileo purpose, a new version of the model has been released. It involves simplifications in the representation of the bottomside as well as a unique formula for a key parameter of the topside formulation previously defined through two equations, each one used for six months of the year. Hence we decided to investigate consecutive improvements and remaining weaknesses of this new formulation. To this extent, we take benefit of various ionosphere data from several European stations (Chilton in UK, Dourbes in Belgium, El Arenosillo and Roquetes in Spain, Pruhonice in Czech Republic) where ionosonde and GPS TEC data are available for different solar activity levels. These data allow us to study NeQuick representation of the ionosphere at mid-latitudes. We investigate the difference between GPS-derived vTEC and corresponding values from NeQuick for the latest years (between solar maximum in 2000 and minimum in 2007) in order to observe the temporal dependencies towards Universal Time, season and solar activity. We use ionosonde data to constrain the model so that we can concentrate on its formulation of the profile only. We especially highlight the improvements from the second version of NeQuick and show the critical importance of the topside formulation. [less ▲]

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See detailHypertension artérielle et sport
Krzesinski, Jean-Marie ULg

Conference (2008, November 18)

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See detailIonospheric variability which degrades the precision of real time GNSS applications
Wautelet, Gilles ULg; Lejeune, Sandrine; Warnant, René ULg

Poster (2008, November 18)

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See detailDirect block of SK2 and SK3 current by the sigma agonist 1,3-di-(2-tolyl)guanidine
Lamy, Cédric; Moreau, Jacqueline ULg; Dilly, Sébastien ULg et al

Poster (2008, November 17)

Sigma receptors are widely distributed in the central nervous system where they modulate neurotransmitter release, receptor function, ionic channel activity and calcium homeostasis. Two subtypes of sigma ... [more ▼]

Sigma receptors are widely distributed in the central nervous system where they modulate neurotransmitter release, receptor function, ionic channel activity and calcium homeostasis. Two subtypes of sigma receptors have been identified (sigma-1 and sigma-2) with different pharmacological profiles, anatomical distribution and physiological functions. 1,3-Di-(2-tolyl)guanidine (DTG) is a sigma-1 and sigma-2 agonist which is widely used to probe the function of these receptors. It has recently been shown that sigma-1 receptor activation reduces the opening of SK channels in the hippocampus. We have observed that DTG (100 µM) reduces the apamin-sensitive afterhyperpolarization (AHP) of dopaminergic neurons within a slice preparation by ~60%, an effect not observed with other sigma agonists. In addition, neither the selective sigma-1 antagonist BD 1047 (30 µM) nor haloperidol (1 µM) blocked the effect of DTG, which suggested that the inhibition of the AHP might result from a direct block of the underlying SK channels. Whole-cell recordings were made from HEK293 cells transiently transfected with rSK2 or hSK3 cDNA in symmetrical K+ conditions with currents activated by a [Cai] of 1 µM. Expressed SK2 and SK3 channels displayed a classical pharmacology, being blocked by apamin with mean IC50’s of 100 pM and 4 nM, respectively. In contrast, both channel subtypes were blocked with equal sensitivity by N-methyl-laudanosine (NML). DTG inhibited both SK2 and SK3 currents with the same potency (IC50’s were ~30 µM). A mutation that rendered both SK2 and SK3 insensitive to apamin and NML produced a current that was still sensitive to DTG. This direct block of SK channels may be important to consider in relation to the pharmacological effects of this compound. [less ▲]

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See detailModelling soil heterotrophic respiration in an agricultural soil: Model structure and first comparison with experimental data.
Buysse, Pauline ULg; Le Dantec, Valérie; Sagnier, Charlotte et al

Poster (2008, November 17)

Ce travail visait à adapter un modèle de respiration hétérotrophe du sol à un site agricole situé en Hesbaye (Belgique) et cultivé avec une rotation betterave sucrière / blé d’hiver / pomme de terre / blé ... [more ▼]

Ce travail visait à adapter un modèle de respiration hétérotrophe du sol à un site agricole situé en Hesbaye (Belgique) et cultivé avec une rotation betterave sucrière / blé d’hiver / pomme de terre / blé d’hiver. A long terme, ce modèle fera partie intégrante d’un modèle plus important qui décrira la respiration totale du sol et l’évolution du contenu en carbone du sol dans les cultures. Le modèle utilisé dans ce travail est dérivé du modèle Century, possède un pas de temps journalier et couvre une échelle spatiale de l’ordre de l’écosystème. La paramétrisation du modèle a été réalisée sur base d’une recherche bibliographique et de données collectées sur le site Carbo-Europe de Lonzée. Les caractéristiques du sol sont issues d’analyses réalisées sur des sols limoneux, typiques de la région de Hesbaye. Les variables conductrices (variables météorologiques et apports de litière) furent obtenues suite à une campagne de mesures de 4 ans réalisée sur le site expérimental de Lonzée. Les paramètres biochimiques du blé, de la pomme de terre et de la betterave furent tirés de la littérature. Une analyse de sensibilité fut réalisée en vue de classer les différents paramètres par rapport à leur impact sur le taux de respiration et les contenus en carbone de chaque pool. Les paramètres les plus importants étaient ceux contrôlant la réponse à la température, l’apport de litière et les teneurs en lignine et en azote. Des différences d’impact à court et long terme ont aussi été mises en évidence, notamment à cause de la dynamique de stabilisation des pools et des types de résidus de culture. Finalement, cette analyse nous a permis de définir de futures expériences qui seraient nécessaires pour améliorer l’ajustement du modèle sur des données expérimentales. [less ▲]

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See detailDétection de cavités et de racines d’altération par tomographie électrique
Robert, Tanguy ULg

Conference (2008, November 15)

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See detailCocaïne: Détermination du délai entre le prélèvement et la consommation
De Backer, Benjamin ULg

Conference (2008, November 14)

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See detailLa perception sociale des risques: étude de cas sur les champs électromagnétiques en Belgique
Brunet, Sébastien ULg; Delvenne, Pierre ULg; Fallon, Catherine ULg

Conference (2008, November 14)

Dans le cadre de cette étude, nous avons voulu mesurer la perception sociale du risque relatif à l’exposition aux champs électromagnétiques. Notre objectif était d’identifier les modes de connaissances ... [more ▼]

Dans le cadre de cette étude, nous avons voulu mesurer la perception sociale du risque relatif à l’exposition aux champs électromagnétiques. Notre objectif était d’identifier les modes de connaissances auxquels se référent des individus qui font face à un risque empreint d’un niveau élevé d’incertitude scientifique. Comment ce public, mobilisé autour d’une problématique complexe, acquiert-il un niveau d’expertise suffisant pour comprendre les enjeux multiples (sociaux, économiques, éthiques, politiques et environnementaux) d’une technologie sur la société et ses modes d’organisation ? Quelle vision a-t-il des acteurs politiques et subpolitiques (Beck, 2001) qui prennent part aux débats ? Quel niveau de confiance accorde-t-il à un monde politique qui, en cas de risque majeur, pourrait invoquer une démarche précautionneuse et récupérer une partie du pouvoir décisionnel qui semblait lui échapper (Brunet, Delvenne & Joris, 2007) ? En situation de haute incertitude scientifique, qui sont les experts ? Quelle relation entretiennent les différents stakeholders 1 avec les autorités publiques? Le risque électromagnétique constitue un exemple éclairant de nouveau risque technologique, qui suscite une mobilisation sociale particulière et met en évidence les défis technologiques, sociaux, éthiques et politiques que nos sociétés occidentales doivent affronter à l’aube du XXIe siècle. [less ▲]

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Peer Reviewed
See detailO-ARM Symposium
Martin, Didier ULg

Conference (2008, November 14)

Detailed reference viewed: 31 (2 ULg)
See detailJules Claskin: l'homme
Baiwir, Esther ULg

Conference (2008, November 13)

Detailed reference viewed: 20 (2 ULg)
See detailLes instruments de la fiscalité environnementale
Bourgeois, Marc ULg

Conference (2008, November 13)

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See detailNatural equivariant quantizations
Radoux, Fabian ULg

Conference (2008, November 12)

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Peer Reviewed
See detailRobust detection of outlying serum protein electrophoretic profiles in External Quality Assessment schemes
Zhang, Lixin ULg

Conference (2008, November 12)

External Quality Assessment (EQA) schemes are national programmes to ensure that results obtained on a particular specimen in a given clinical laboratory are compatible with those obtained by other ... [more ▼]

External Quality Assessment (EQA) schemes are national programmes to ensure that results obtained on a particular specimen in a given clinical laboratory are compatible with those obtained by other laboratories on the same specimen. EQA schemes are traditionally facing the problem of outlier detection of single analytes, e.g., glucose or cholesterol. Recently, serum protein electrophoresis was tested to be subsequently implemented on a regular basis in EQA programmes. This is a laboratory test which consists of five fractions (albumin, α1, α2, β and γ globulins) and the sum of them is equal to 100% of total proteins. So far, in EQA the five fractions have been analyzed separately as for the univariate analytes, without considering the correlation and the linear relationship between them. The minimum covariance determinant (MCD) estimator (Rousseeuw and van Driessen 1999) provides an interesting robust approach to analyze EQA electrophoresis results from a global standpoint. This talk focuses on comparing the results obtained by the traditional univariate approach and the robust MCD approach (Zhang et al. 2008). As illustrated on electrophoretic data from the Belgian EQA scheme, the MCD approach improves the detection of poor performing laboratories. Simple graphical representation of the outliers will be demonstrated at the end of the talk. [less ▲]

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See detailEffect of climate change on flood risk along river Ourthe
Dewals, Benjamin ULg; Ernst, Julien ULg; Pirotton, Michel ULg

Conference (2008, November 12)

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See detailEffect of climate change on flood risk along river Ourthe
Dewals, Benjamin ULg; Ernst, Julien ULg

Conference (2008, November 12)

Detailed reference viewed: 13 (2 ULg)
See detailPharmacology of tiludronate in horses
Delguste, Catherine ULg

Conference (2008, November 08)

Detailed reference viewed: 17 (1 ULg)
Peer Reviewed
See detailCognitive and affective mechanisms involved in hallucination-proneness
Laroi, Frank ULg

Conference (2008, November 08)

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See detailWortlaut et remplissement
Gyemant, Maria ULg

in Marthelot, Perrine (Ed.) S’orienter dans le langage : l’indexicalité (2008, November 08)

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See detailFollow-up on EUCAST
MELIN, Pierrette ULg

Conference (2008, November 06)

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Peer Reviewed
See detailVenture Creation Intentions and the Seasons of Adult Development
Heuer, Annamaria ULg; Surlemont, Bernard ULg

Conference (2008, November 06)

Objectives: The objective of the paper is to identify the potential impact of different forms of aging (e.g. biological, psychological and psychosocial aging) on entrepreneurial intention. Thus, the key ... [more ▼]

Objectives: The objective of the paper is to identify the potential impact of different forms of aging (e.g. biological, psychological and psychosocial aging) on entrepreneurial intention. Thus, the key focus will be on aging-related changes of attitudes, subjective norms and feasibility perceptions and their influence on intention. Prior work: Numerous studies have applied cognition research-based models to understand the factors that impact entrepreneurial intentions (e.g. Davidsson, 1995; Kolvereid, 1996; Krueger, Reilly and Carsrud, 2000; Autio et al., 2001; Douglas and Shepherd, 2002; Kristiansen and Indarti, 2004). Most scholars, however, have conducted their studies on university students (e.g. Van Gelderen et al., 2006). This choice is mostly motivated by an easier access to data. As a consequence, this may have introduced a bias that underestimates the potential influence of life-stage-related differences on entrepreneurial intention. Approach: The paper will present a literature review of the theories that look at the impact of aging on career intentions (for instance, Lévesque and Minniti, 2006; Ornstein et al., 1989). The approach is to start on the structure of the intentions model (Ajzens’ Theory of Planned Behaviour) as a framework to integrate these pieces of research. Results: This paper is conceptual in nature, transferring important ideas of adult-development to the domain of entrepreneurship. The argumentation will show the differences in perceived desirability and feasibility are related to aging, such as high plasticity of attitude in early adulthood (e.g. Visser et al., 1998), higher change susceptibility in mid-age (Levinson, 1986; Lévesque and Minniti, 2006), and dominant self-limiting roles and decreasing willingness to bear uncertainty in the later eras (Greller, 1995; Shane, 2003). Ultimately, the paper will contribute to formulate hypotheses relating aging stages and possible drivers of entrepreneurial intention. Implications: If the drivers of entrepreneurial intention change according to age, then programmes to stimulate entrepreneurship may have to be adapted according to the target audience. If potential entrepreneurs at later stages such as the “thirties transition” are more susceptible to change, and considering that due to population aging and increasing retirement age in the western world the economic importance of “older” entrepreneur’s is likely to increase, why not stimulate them more? Value: To date, there have only been sporadic, short argumentations for aging-related changes of intentional antecedents. We fill this gap and provide a more rigorous review of this problematic. [less ▲]

Detailed reference viewed: 66 (6 ULg)