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See detailA first approximation for quantization of singular spaces
Poncin, Norbert; Radoux, Fabian ULg; Wolak, Robert

in Journal of Geometry & Physics (2009), 59(4), 503-518

Many mathematical models of physical phenomena that have been proposed in recent years require more general spaces than manifolds. When taking into account the symmetry group of the model, we get a ... [more ▼]

Many mathematical models of physical phenomena that have been proposed in recent years require more general spaces than manifolds. When taking into account the symmetry group of the model, we get a reduced model on the (singular) orbit space of the symmetry group action. We investigate quantization of singular spaces obtained as leaf closure spaces of regular Riemannian foliations on compact manifolds. These contain the orbit spaces of compact group actions and orbifolds. Our method uses foliation theory as a desingularization technique for such singular spaces. A quantization procedure on the orbit space of the symmetry group–that commutes with reduction–can be obtained from constructions which combine different geometries associated with foliations and new techniques originated in Equivariant Quantization. The present paper contains the first of two steps needed to achieve these just detailed goals. [less ▲]

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See detailWorld Street: Internet au coeur de la révolte des investisseurs
Choffray, Jean-Marie ULg

E-print/Working paper (2009)

Cet article évoque la "révolte" des investisseurs; une évolution technologique qui remet en question le mode de fonctionnement des marchés et le rôle exercé depuis toujours par les intermédiaires ... [more ▼]

Cet article évoque la "révolte" des investisseurs; une évolution technologique qui remet en question le mode de fonctionnement des marchés et le rôle exercé depuis toujours par les intermédiaires financiers; une discipline scientifique nouvelle - Internet-Based Global Investing - qui se situe au carrefour de l’informatique, de la statistique, du marketing et de la finance; un écosystème susceptible de contribuer au développement d’innovations majeures dans les domaines de l’information, de l’analyse, de la sélection et du contrôle des investissements; et, enfin, une opportunité exceptionnelle pour les investisseurs, tant individuels qu’institutionnels, qui se retrouvent, dès à présent, au centre de ce nouvel espace de liberté, d'égalité et de responsabilité. [less ▲]

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See detailAnnotation of Ivane Mortelette's "'A Proof that I Did Exist': Janet Frame and Photography"
Tunca, Daria ULg

in Routledge Annotated Bibliography of English Studies (2009)

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See detailSur la consistance du lissage des contraintes par convolution
Debongnie, Jean-François ULg

in Agouzoul, Mohammed (Ed.) Actes du neuvième congrès de mécanique (2009, April)

This paper is devoted to the analysis of a stress-smoothing procedure by convolution. The key result is that any convolution kernel does not generally lead to accurate results, it is to say, a consistency ... [more ▼]

This paper is devoted to the analysis of a stress-smoothing procedure by convolution. The key result is that any convolution kernel does not generally lead to accurate results, it is to say, a consistency condition has to be verified. Consistent kernels are then developed. [less ▲]

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See detailUn menu qui pèse dans la balance climatique
Ozer, Pierre ULg; Perrin, Dominique ULg

Article for general public (2009)

Un menu qui pèse dans la balance climatique Prenons un menu un brin festif: potage, plat, dessert. Calculons : ensemble, les denrées parcourent 218 000 kilomètres avant de tomber dans notre assiette. Et ... [more ▼]

Un menu qui pèse dans la balance climatique Prenons un menu un brin festif: potage, plat, dessert. Calculons : ensemble, les denrées parcourent 218 000 kilomètres avant de tomber dans notre assiette. Et émettent 37,5 kg de CO2. À ce prix, l’avion est-il vraiment inéluctable pour transporter la nourriture? [less ▲]

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See detailThe carriage of larval Echinococcus multilocularis and other cestodes by the musk rat (Ondatra zibethicus) along the Ourthe river and its tributaries (Belgium)
Mathy, Anne ULg; Hanosset, Régis; Adant, S. et al

in Journal of Wildlife Diseases (2009), 45

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See detailYou do not find your own face faster; you just look at it longer
Devue, Christel ULg; Van der Stigchel, Stefan; Brédart, Serge ULg et al

in Cognition (2009), 111(1), 114-122

Previous studies investigating the ability of high priority stimuli to grab attention reached contradictory outcomes. The present study used eye tracking to examine the effect of the presence of the self ... [more ▼]

Previous studies investigating the ability of high priority stimuli to grab attention reached contradictory outcomes. The present study used eye tracking to examine the effect of the presence of the self-face among other faces in a visual search task in which the face identity was task-irrelevant. We assessed whether the self-face (1) received prioritized selection (2) caused a difficulty to disengage attention, and (3) whether its status as target or distractor had a differential effect. We included another highly familiar face to control whether possible effects were self-face specific or could be explained by high familiarity. We found that the self-face interfered with the search task. This was not due to a prioritized processing but rather to a difficulty to disengage attention. Crucially, this effect seemed due to the self-face’s familiarity, as similar results were obtained with the other familiar face, and was modulated by the status of the face since it was stronger for targets than for distractors. [less ▲]

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See detailSurvival of Freeze-dried Leuconostoc mesenteroides and Lactobacillus plantarum Related to Their Cellular Fatty Acids Composition during Storage
Coulibaly, Ibourahema ULg; Yao, Amenan Anastasie ULg; Lognay, Georges ULg et al

in Applied Biochemistry and Biotechnology (2009), 157(1), 70-84

Lactic acid bacteria strains Lactobacillus plantarum CWBI-B534 and Leuconostoc ssp. mesenteroïdes (L. mesenteroïdes) Kenya MRog2 were produced in bioreactor, concentrated, with or without cryoprotectants ... [more ▼]

Lactic acid bacteria strains Lactobacillus plantarum CWBI-B534 and Leuconostoc ssp. mesenteroïdes (L. mesenteroïdes) Kenya MRog2 were produced in bioreactor, concentrated, with or without cryoprotectants. In general, viable population did not change significantly after freeze-drying (p>0.05). In most cases, viable population for cells added with cryoprotectants was significantly lower than those without (p<0.05). Cellular fatty acids (CFAs) from the two strains in this study were analyzed before and after freeze-drying. Six CFAs were identified, namely, palmitic (C16:0), palmitoleic (C16:1), stearic (C18:0), oleic (C18:1), linoleic (C18:2), and linolenic (C18:3) acids were identified. Four of them, C16:0, C16:1, C18:0, and C18:1, make up more than 94% or 93% of the fatty acids in L. mesenteroides and L. plantarum, respectively, with another one, namely, C18:3, making a smaller (on average 5–6%, respectively) contribution. The C18:2 contributed very small percentages (on average≤1%) to the total in each strain. C16:0 had the highest proportion at most points relative to other fatty acids. Moisture content and water activity (a w) increased significantly during the storage period. It was observed that C16:1/C16:0, C18:0/C16:0 and C18:1/C16:0 ratios for freeze-dried L. mesenteroides or L. plantarum, with or without cryoprotectants, did not change significantly during the storage period. According to the packaging mode and storage temperatures, C18:2/C16:0 and C18:3/C16:0 ratios for freeze-dried L. mesenteroides and L. plantarum with or without cryoprotectants decreased as the storage time increased. However, a higher C18:2/C16:0 or C18:3/C16:0 ratio for L. mesenteroides and L. plantarum was noted in the freeze-dried powder held at 4 °C or under vacuum and in dark than at 20 °C or in the presence of oxygen and light [less ▲]

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See detailBGP-aware IGP Link Weight Optimization in Presence of Route Reflectors
Balon, Simon ULg; Leduc, Guy ULg

in IEEE INFOCOM 2009 (2009, April)

The first generation of IGP Link Weight Optimizers (LWOs) was based on presumably invariant intra-domain traffic matrices only, ignoring the fact that updating link weights had a side effect on these ... [more ▼]

The first generation of IGP Link Weight Optimizers (LWOs) was based on presumably invariant intra-domain traffic matrices only, ignoring the fact that updating link weights had a side effect on these traffic matrices due to hot-potato routing, thus result- ing in suboptimal link weight settings, and sometimes to very bad performance. The second generation of IGP LWOs, referred to as BGP-aware LWOs, has been able to optimize link weights while taking hot-potato effects into account. However, these tools relied on the complete visibility assumption fulfilled by e.g. a full-mesh iBGP configu- ration. This paper proposes a third generation LWO, still BGP-aware, but also able to work with iBGP con- figurations based on route reflectors, which usually hide some reachability information from routers. This partial visibility may cause various problems, including path deflections (i.e., the actual egress router is not the expected one), which may in turn create forwarding loops. Our LWO embeds a BGP routing solver which can always predict the actual egress router, even when route reflectors are used. It can also forbid solutions leading to path deflection. Its efficiency is evaluated on a real dataset, and compared to other LWOs. [less ▲]

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See detailTime series of 12CO and 13CO at northern mid-latitudes: Determination of Partial Column and δ13C seasonal and interannual variations
Mahieu, Emmanuel ULg; Duchatelet, Pierre ULg; Rinsland, C. P. et al

in Geophysical Research Abstracts (2009, April), 11(EGU2009-10017-1),

Carbon monoxide (CO) is an important reactive gas in the troposphere. It is emitted at the ground level by fossil fuel combustion and biomass burning. Biogenic sources and oceans as well as oxidation of ... [more ▼]

Carbon monoxide (CO) is an important reactive gas in the troposphere. It is emitted at the ground level by fossil fuel combustion and biomass burning. Biogenic sources and oceans as well as oxidation of methane and nonmethane hydrocarbons complete the emissions budget. Large uncertainties still affect the relative contributions of the identified anthropogenic and natural sources. Destruction by the hydroxyl radical (OH) is the main removal process for CO in both the troposphere and the stratosphere. The resulting average tropospheric lifetime of CO varies from several weeks to a few months. Two approaches have been developed and optimized to independently retrieve abundances of 12CO and 13CO from high-resolution ground-based infrared solar spectra, using sets of carefully selected lines and the SFIT-2 (v3.91) algorithm which implements the optimal estimation method. The corresponding products will be described and characterized in terms of error budget and information content. These strategies have allowed us to produce partial column time series of 12CO and 13CO, using spectra recorded on a regular basis at the Jungfraujoch station (46.5ºN, 8.0ºE, 3580 m asl, Swiss Alps), a site of the Network for the Detection of Atmospheric Composition Change (NDACC). The seasonal and interannual changes observed in the 12CO,13CO and δ13C (13C/12C) data sets will be presented and discussed. Complementary zonal mean time series derived from occultation measurements collected by the ACE-FTS instrument onboard the Canadian SCISAT-1 platform since 2004 will also be included and analyzed, focusing on the upper troposphere-lower stratosphere region of the atmosphere. Finally, we will use GEOS-Chem 3-D chemistry transport model results to help in the interpretation of the short and long-term variations characterizing the ground-based and satellite data sets, focusing on the factors influencing the partitioning between the two CO isotopologues. [less ▲]

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See detailGreenland ice sheet projections from IPCC AR4 global models
Franco, Bruno ULg; Fettweis, Xavier ULg; Erpicum, Michel ULg et al

Poster (2009, April)

The atmosphere-ocean general circulation models (AOGCMs) used for the IPCC 4th Assessment Report (IPCC AR4) are evaluated for the Greenland ice sheet (GrIS) current climate modelling. The most efficient ... [more ▼]

The atmosphere-ocean general circulation models (AOGCMs) used for the IPCC 4th Assessment Report (IPCC AR4) are evaluated for the Greenland ice sheet (GrIS) current climate modelling. The most efficient AOGCMs are chosen by comparison between the 1970-1999 outputs of the Climate of the twentieth Century experiment (20C3M) and reanalyses (ECMWF, NCEP/NCAR). This comparison reveals that surface parameters such as temperature and precipitation are highly correlated to the atmospheric circulation (500 hPa geopotential height) and its interannual variability (North Atlantic oscillation). The outputs of the three most efficient AOGCMs are then used to assess the changes planned by three IPCC greenhouse gas emissions scenarios (SRES) for the 2070-2099 period. Future atmospheric circulation changes should dampen the west-to-east circulation (zonal flow) and should enhance the Meridional Overturning Circulation (MOC). As a consequence, this provides more heat and moisture to the GrIS, increasing temperature on the whole ice sheet and precipitation on the north-eastern region. It is also shown that the GrIS surface mass balance (SMB) anomalies from the SRES A1B scenario are about -300 km³/yr with respect to the 1970-1999 period, leading to 5 cm of global sea-level rise (SLR) for the end of the 21st century. This work helps to choose the boundaries conditions for AOGCMs downscaled future projections. [less ▲]

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See detailMieux Traiter le diabète permet-il de vivre plus longtemps?
Scheen, André ULg; Philips, Jean-Christophe ULg

in Médecine Clinique Endocrinologie & Diabète (2009), hors série(avril 2009), 2-7

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See detailCombinaison fixe perindopril-amlodipine (Coveram®) dans le traitement de l'hypertension artérielle et de l'insuffisance coronaire.
Scheen, André ULg; Krzesinski, Jean-Marie ULg

in Revue Médicale de Liège (2009), 64(4), 223-227

Coveram® is a new fixed combination of an angiotensin converting enzyme inhibitor, perindopril, and a calcium antagonist, amlodipine. This new medication is indicated for the treatment of arterial ... [more ▼]

Coveram® is a new fixed combination of an angiotensin converting enzyme inhibitor, perindopril, and a calcium antagonist, amlodipine. This new medication is indicated for the treatment of arterial hypertension and/or stable coronary heart disease. Such fixed combination of two molecules that have been extensively evaluated according to evidence-based medicine offers the advantage of an excellent efficacy, associated with a good tolerance profile, and favours patient’s compliance. The marketing of different formulations of Coveram® combining various dosages allows easy adjustment and titration of each of the components according to the individual patient’s characteristics. [less ▲]

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See detailLayer-by-layer self-assembled chitosan coating on electrospun nanofibers
Croisier, Florence ULg; Aqil, Abdelhafid ULg; Detrembleur, Christophe ULg et al

Poster (2009, April)

By combining electrospinning technique and layer-by-layer deposition, we produced a new material made of multilayered, chitosan-based nanofibers. Layer-by-layer (LBL) is a well-known method for surface ... [more ▼]

By combining electrospinning technique and layer-by-layer deposition, we produced a new material made of multilayered, chitosan-based nanofibers. Layer-by-layer (LBL) is a well-known method for surface coating, based on electrostatic interactions. It enables the controllable deposition of a variety of polyions including synthetic and natural materials, with designable layer structure, defined wall thickness and size. Electrospinning (ESP) technique allows the fabrication of polymer fibers ranging from nanometers to a few microns in diameter, depending on the polymer characteristics (a.o. molecular weight, solution viscosity and conductivity) and processing conditions (electric potential, distance between syringe-capillary and collection plate, concentration, flow rate). Mats of nanofibers produced by ESP display a very large surface area-to-volume ratio and high porosity with very small pore size. The nanometric scale of electrospun fibers also proves a positive effect on cellular growth, as fibers mats mimic extracellular matrix structure. The association of these two techniques with the use of biocompatible and biodegradable polymers such as chitosan, gives outstanding prospects in the field of biomedical applications, especially for the preparation of wound dressings, artificial skin or tissue engineering scaffolds. In the present study, a charged copolymer, poly(methylmethacrylate-block-methacrylic acid), was added to a poly(ε-caprolactone) or poly(D,L-lactide) solution before electrospinning in order to obtain charges on fibers surface. Oppositely charged polyelectrolytes – chitosan and poly(styrene sulfonate) or hyaluronic acid – were then alternately deposited on these aliphatic polyester fiber “cores” using LBL method. The aliphatic polyester core was also removed selectively to confirm the existence of a multilayered shell, obtaining hollow fibers. [less ▲]

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See detailCycles in the Temperature Data Are Induced by the Sun
Nicolay, Samuel ULg; Mabille, Georges ULg; Fettweis, Xavier ULg et al

Poster (2009, April)

The presence of two cycles of period of 30 and 42 months approximatively has been observed in temperature records and climatic indices. Moreover, it has been shown that these cycles are statistically ... [more ▼]

The presence of two cycles of period of 30 and 42 months approximatively has been observed in temperature records and climatic indices. Moreover, it has been shown that these cycles are statistically significant. Here we outline the role played by the Sun in the presence of these cycles, observed in time series. To do so, we use IPCC AR4 climatic models, sunspot number data and the Morlet wavelet method. [less ▲]

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