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See detailInvestigation of SDS, DTAB and CTAB micelle microviscosities by electron spin resonance
Bahri, Mohamed Ali ULg; Hoebeke, Maryse ULg; Grammenos, Angeliki ULg et al

in Colloids and Surfaces A : Physicochemical and Engineering Aspects (2006), 290(1-3), 206-212

Electron spin resonance spectroscopy (ESR) of the nitroxide labelled fatty acid probes (5-, 16-doxyl stearic acid) was used to monitor the micelle microviscosity of three surfactants at various ... [more ▼]

Electron spin resonance spectroscopy (ESR) of the nitroxide labelled fatty acid probes (5-, 16-doxyl stearic acid) was used to monitor the micelle microviscosity of three surfactants at various concentrations in aqueous solution: sodium dodecyl sulphate (SDS), dodecyltrimethylammonium bromide (DTAB) and cetyltrimethylammonium bromide (CTAB). At low surfactant concentration, there is no micelle, the ESR probe is dissolved in water/surfactant homogeneous phase and gives his microviscosity. At higher surfactant concentration, an abrupt increase in microviscosity indicates the apparition of micelles and, the solubilization of the probes in micelles. The microviscosity of the three surfactants, in a large surfactant range, was obtained as well as the critical micelle concentration (CMC). The microviscosity increased slightly with the increase in surfactant concentration. Phosphate buffer lowered the CMC value and generally increased the microviscosity. (c) 2006 Elsevier B.V. All rights reserved. [less ▲]

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See detailA scalable and decentralized fast-rerouting scheme with efficient bandwidth sharing
Balon, Simon ULg; Mélon, Laurent; Leduc, Guy ULg

in Computer Networks (2006), 50(16), 3043-3063

This paper focuses on the protection of virtual circuits (Label Switched Paths, LSPs) in a (G)MPLS (Generalised Multi-Protocol Label Switching) network. The proposed algorithm is designed to protect ... [more ▼]

This paper focuses on the protection of virtual circuits (Label Switched Paths, LSPs) in a (G)MPLS (Generalised Multi-Protocol Label Switching) network. The proposed algorithm is designed to protect traffic with strong delay requirements such as EF (Expedited Forwarding) ordered aggregates in a DiffServ domain. Indeed, for this type of application, we need fast restoration in case of failure. The duplication of all the packets in a 1 + 1 end-to-end restoration scheme consumes a large amount of bandwidth. Furthermore, end-to-end recovery with bandwidth sharing schemes are usually considered to be far too slow. Local fast-rerouting is a solution which can compete with restoration times and bandwidth consumption offered by SONET self-healing rings. Our scheme includes a sophisticated resource aggregation mechanism based on the concepts of "backup-backup aggregation" and "backup-primary aggregation". The path selection algorithm is also designed to efficiently reduce the resource usage. Moreover, when considering LSPs at different preemption levels, our algorithm is able to correctly calculate the amount of bandwidth that can be preempted despite the sharing of resource. We show that our approach, though local, can compete with the state-of-the-art end-to-end recovery schemes in terms of resource consumption. The major contribution of our scheme, the "backup-primary aggregation", was then also used in the context of end-to-end recovery and improved its performance substantially. To be able to save a maximum amount of bandwidth in a decentralised implementation, the nodes that compute backup LSPs need to obtain a certain amount of link-state information. We propose a solution where the nodes learn almost all the information they need with RSVP messages. This drastically reduces the information that needs to be flooded in the whole network and is the first scalable decentralised solution capable of sharing a large amount of bandwidth. (c) 2005 Elsevier B.V. All rights reserved. [less ▲]

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See detailDIVA Graphical User Interface
Troupin, Charles ULg; Sirjacobs, Damien ULg; Beckers, Jean-Marie ULg

Conference (2006, November 13)

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See detailEffect of Ga doping on magneto-transport properties in colossal magnetoresistive La0.7Ca0.3Mn1-xGaxO3 (0 < x < 0.1)
Pekala, M.; Mucha, Jan ULg; Vertruyen, Bénédicte ULg et al

in Journal of Magnetism and Magnetic Materials (2006), 306(2), 181-190

Samples of La0.7Ca0.3Mn1-xGaxO3 with x = 0, 0.025, 0.05 and 0.10 were prepared by standard solid-state reaction. They were first characterized chemically, including the microstructure. The magnetic ... [more ▼]

Samples of La0.7Ca0.3Mn1-xGaxO3 with x = 0, 0.025, 0.05 and 0.10 were prepared by standard solid-state reaction. They were first characterized chemically, including the microstructure. The magnetic properties and various transport properties, i.e. the electrical resistivity, magnetoresistivity (for a field below 8 T), thermoelectric power and thermal conductivity measured each time on the same sample, are reported. The markedly different behaviour of the x = 0.1 sample from those with a smaller Ga content, is discussed. The dilution of the Mn3+/Mn4+ interactions with Ga doping considerably reduces the ferromagnetic double exchange interaction within the manganese lattice leading to a decrease of the Curie temperature. The polaron binding energy varies from 224 to 243 meV with increased Ga doping. (C) 2006 Elsevier B.V. All rights reserved. [less ▲]

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See detailEthologie des fourmis Eutetramorium mocquerysi (Emery, 1900) Hymenoptera, Formicidae, en laboratoire
Raharimalala, Fara Nantenaina ULg

Master of advanced studies dissertation (2006)

The laboratory breeding study of Eutetramorium mocquerysi was conducted in an artificial fourmiliere: formicarium. The colonies were nourished with portions of insects (larvae of coleoptera, locusts ... [more ▼]

The laboratory breeding study of Eutetramorium mocquerysi was conducted in an artificial fourmiliere: formicarium. The colonies were nourished with portions of insects (larvae of coleoptera, locusts, cockroaches. ..).All social insects have several morphoanatomic castes (worker dominating, workers of high ranks: being able to become dominating, workers of low ranks: veritable worker,and the ant male). As with all social insects, the life of the colony is regulated by the queen. However, in the species studied no veritable queen exists. This function is fulfilled by a dominating worker, whose dominance is assured partly by constant fights with the young workers and partly by maximum ovarial development. Dominant worker and workers of the high ranks have six (6) ovarioles, while the veritable workers possess just two (2) ovarioles. The presence of a dominant worker in the nest allows the regulation of the laborious life of the colony, the maintenance of inferior workers ranks and the control of male abundance in the colony. [less ▲]

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See detailPour une théorie de l'agir environnemental
Mormont, Marc ULg

Conference (2006, November 09)

The paper proposes a theoretical approach of ecocitizenship that puts the empahasis ont the various was people make trade-off between various value systems.

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See detailGifted children and the physician
Vanmeerbeek, Marc ULg

Scientific conference (2006, November 05)

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See detailThe in situ polymerization of monoethylenically unsaturated monomers with oligomeric or polymeric secondary amines
Detrembleur, Christophe ULg; Rüdiger, Claus; Meyer, Rolf-Volker

Patent (2006)

The present invention relates to a new process for the preparation of well-defined random and block polymers or copolymers using hindered secondary amine-oligomers or polymers.

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See detailThe Seismology Programme of CoRoT
Michel, Eric; Baglin, A.; Auvergne, M. et al

in Proceedings of "The CoRoT Mission Pre-Launch Status - Stellar Seismology and Planet Finding (2006, November 01)

We introduce the main lines and specificities of the CoRoT Seismology Core Programme. The development and consolidation of this programme has been made in the framework of the CoRoT Seismology Working ... [more ▼]

We introduce the main lines and specificities of the CoRoT Seismology Core Programme. The development and consolidation of this programme has been made in the framework of the CoRoT Seismology Working Group. With a few illustrative examples, we show how CoRoT data will help to address various problems associated with present open questions of stellar structure and evolution. [less ▲]

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See detailWhy Bothering to Measure Stellar Rotation with CoRoT?
Goupil, Marie-José; Moya, A.; Suarez, J. C. et al

in ESA Special Publication (2006, November 01)

One important goal of the CoRoT experiment is to obtain information about the internal rotation of stars, in particular the ratio of central to surface rotation rates. This will provide constraints on the ... [more ▼]

One important goal of the CoRoT experiment is to obtain information about the internal rotation of stars, in particular the ratio of central to surface rotation rates. This will provide constraints on the modelling of transport mechanisms of angular momentum acting in radiative (rotationally induced turbulent) and convective zones (plumes, extension beyond convectively instable regions). Relations between the surface rotation period and age, magnetic activity, mass loss and other stellar characteristics can also be studied with a statistically significant set of data as will be provided by Corot. We present various theoretical efforts performed over the past years in order to develope the theoretical tools which will enable us to study rotation with Corot. [less ▲]

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See detailRotational Splittings with CoRoT, Expected Number of Detections and Measurement Accuracy
Goupil, M. J.; Lochard, J.; Samadi, R. et al

in ESA Special Publication (2006, November 01)

One of the main goal of the CoRoT experiment is to determine the internal rotation of stars. A seismic measure of rotation requires the detection and an accurate measurement of rotational splittings. Our ... [more ▼]

One of the main goal of the CoRoT experiment is to determine the internal rotation of stars. A seismic measure of rotation requires the detection and an accurate measurement of rotational splittings. Our ability to achieve this goal with CoRoT observations depends on the properties of the target star (in short: spectral type and distance) and will be discussed. [less ▲]

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See detailL'astronomie dans le monde
Manfroid, Jean ULg

Article for general public (2006)

Glace et éclairs; Astéroïdes; Pluton; Avatars et avanie d'une petite planète (Xena, Eris); Nuage d'éthane sur Titan; Lacs de Titan; La NASA scrute Mars; Les express Mars et Venus; Cydonia, le visage sur ... [more ▼]

Glace et éclairs; Astéroïdes; Pluton; Avatars et avanie d'une petite planète (Xena, Eris); Nuage d'éthane sur Titan; Lacs de Titan; La NASA scrute Mars; Les express Mars et Venus; Cydonia, le visage sur Mars; Transit d'Ariel; Lune; Gonflée, la planète; Terres, terres!; Une planète extrasolaire aurait abrité de l'eau liquide; Des planètes au centre de la Voie Lactée; Anatomie d'un disque protoplanétaire; CHRX73 et pseudo-planète; Systèmes étranges; Premières galaxies; Voie Lactée; Neutrinos; RCW 86 [less ▲]

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See detailHigh accuracy transit photometry of the planet OGLE-TR-113b with a new deconvolution-based method
Gillon, Michaël ULg; Pont, F.; Moutou, C. et al

in Astronomy and Astrophysics (2006), 459

A high accuracy photometry algorithm is needed to take full advantage of the potential of the transit method for the characterization of exoplanets, especially in deep crowded fields. It has to reduce to ... [more ▼]

A high accuracy photometry algorithm is needed to take full advantage of the potential of the transit method for the characterization of exoplanets, especially in deep crowded fields. It has to reduce to the lowest possible level the negative influence of systematic effects on the photometric accuracy. It should also be able to cope with a high level of crowding and with large-scale variations of the spatial resolution from one image to another. A recent deconvolution-based photometry algorithm fulfills all these requirements, and it also increases the resolution of astronomical images, which is an important advantage for the detection of blends and the discrimination of false positives in transit photometry. We made some changes to this algorithm to optimize it for transit photometry and used it to reduce NTT/SUSI2 observations of two transits of OGLE-TR-113b. This reduction has led to two very high precision transit light curves with a low level of systematic residuals, used together with former photometric and spectroscopic measurements to derive new stellar and planetary parameters in excellent agreement with previous ones, but significantly more precise. [less ▲]

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See detailAn asteroseismic study of the β Cephei star β Canis Majoris
Mazumdar, A.; Briquet, Maryline ULg; Desmet, M. et al

in Astronomy and Astrophysics (2006), 459

Aims.We present the results of a detailed analysis of 452 ground-based, high-resolution high S/N spectroscopic measurements spread over 4.5 years for β Canis Majoris with the aim of determining the ... [more ▼]

Aims.We present the results of a detailed analysis of 452 ground-based, high-resolution high S/N spectroscopic measurements spread over 4.5 years for β Canis Majoris with the aim of determining the pulsational characteristics of this star, and then using them to derive seismic constraints on the stellar parameters.<BR /> Methods: .We determined pulsation frequencies in the Si III 4553 Å line with Fourier methods. We identified the m-value of the modes by taking the photometric identifications of the degrees ℓ into account. To this end we used the moment method together with the amplitude and phase variations across the line profile. The frequencies of the identified modes were used for a seismic interpretation of the structure of the star.<BR /> Results: .We confirm the presence of the three pulsation frequencies already detected in previous photometric datasets: f[SUB]1[/SUB] = 3.9793~c d[SUP]-1[/SUP] (46.057~μHz), f[SUB]2[/SUB] = 3.9995~c d[SUP]-1[/SUP] (46.291~μHz), and f[SUB]3[/SUB] = 4.1832~c d[SUP]-1[/SUP] (48.417~μHz). For the two modes with the highest amplitudes, we unambiguously identify (ℓ_1,m_1) = (2,2) and (ℓ_2,m_2) = (0,0). We cannot conclude anything for the third mode identification, except that m[SUB]3[/SUB] > 0. We also deduce an equatorial rotational velocity of 31 ± 5~km s[SUP]-1[/SUP] for the star. We show that the mode f[SUB]1[/SUB] must be close to an avoided crossing. Constraints on the mass (13.5 ± 0.5~μHz), age (12.4 ± 0.7 Myr), and core overshoot (0.20 ± 0.05 H_P) of β CMa are obtained from seismic modelling using f[SUB]1[/SUB] and f_2.<BR /> [less ▲]

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See detailLutte biologique contre les maladies de post-récolte des pommes: sélection des antagonistes de Penicillium expansum et de Botrytis cinerea
Achbani, E. H.; Mounir, R.; El Jaafari, S. et al

in Proceeding : 6ème congrés de l'Association Marocaine de Protection des plantes (2006)

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See detailPrédiction de mobilité par le mobile ou par le point d'accès: comparaison sur base de traces réelles
François, Jean-Marc; Leduc, Guy ULg

in CFIP'2006 (2006, November)

Le problème de la prédiction de mobilité se définit comme le fait de deviner quel sera le prochain point d'accès rencontré par un terminal mobile lors de son déplacement dans un réseau sans fil. Les ... [more ▼]

Le problème de la prédiction de mobilité se définit comme le fait de deviner quel sera le prochain point d'accès rencontré par un terminal mobile lors de son déplacement dans un réseau sans fil. Les prédictions faites permettent d'améliorer la qualité de service fournie par le réseau en lui permettant de prendre des mesures pro-actives (telles des réservations de ressources). Les agents de prédiction se classent principalement en deux catégories: les agents liés à un mobile particulier (responsables d'anticiper les déplacements de celui-ci) et ceux liés à un point d'accès (prédisant le prochain point d'attache de tous les terminaux y étant connectés). Cet article vise à comparer les deux méthodes à l'aide de traces réelles tirées d'un réseau WiFi de grande taille. Il montre que certains postulats souvent admis (comme le fait que les habitudes de mouvement du week-end sont différentes de celles du reste de la semaine) doivent être revus. [less ▲]

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See detailConception d'un protocole de contrôle de topologie pour les overlays construits sur des réseaux ad hoc
Calomme, Sandrine; Leduc, Guy ULg

in CFIP'2006 (2006, November)

Nous présentons un algorithme de création d'une structure overlay efficace pour l'inondation de messages entre un sous-ensemble donné de nœuds ad hoc. Nous exposons les similarités que ce problème ... [more ▼]

Nous présentons un algorithme de création d'une structure overlay efficace pour l'inondation de messages entre un sous-ensemble donné de nœuds ad hoc. Nous exposons les similarités que ce problème présente avec celui du contrôle de topologie et soulignons ses particularités. NBO (Neighbour-Based Overlay topology control protocol), emploie uniquement des informations faciles à obtenir : la distance, exprimée en hops, entre chaque paire de nœuds et leur identifiant. Nous avons estimé la qualité de la structure obtenue sur base de la bande passante consommée par inondation, de la charge des nœuds overlay lors d'une inondation, et du temps nécessaire à la réception d'un message par tous les membres de l'overlay. NBO est plus performant que le meilleur protocole de contrôle de topologie overlay homogène possible. [less ▲]

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See detailLa duloxetine (Cymbalta)
Pitchot, William ULg

in Revue Médicale de Liège (2006), 61(11), 787-90

Duloxetine (Cymbalta is an antidepressant of the class of serotonin noradrenaline reuptake inhibitors. The efficacy of duloxetine 60 mg/day has been well demonstrated in the acute and long term treatment ... [more ▼]

Duloxetine (Cymbalta is an antidepressant of the class of serotonin noradrenaline reuptake inhibitors. The efficacy of duloxetine 60 mg/day has been well demonstrated in the acute and long term treatment of major depression. The level of effectiveness of duloxetine is particularly high and associated with a shorter latency of action. Duloxetine also exhibits antinociceptive properties independently of the antidepressant effect. The side-effect profile of duloxetine is particularly good and similar to selective serotonin reuptake inhibitors with mainly nausea. In total, duloxetine represents a real progress in the pharmacological treatment of major depression. [less ▲]

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