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See detailOptical Vectorial Vortex Coronagraphs using Liquid Crystal Polymers: theory, manufacturing and laboratory demonstration
Mawet, D.; Serabyn, E.; Liewer, K. et al

in Optics Express (2009), 17

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See detailDust in the inner regions of debris disks around A stars
Akeson, R. L.; Ciardi, D. R.; Millan-Gabet, R. et al

in Astrophysical Journal (2009), 691

We present infrared interferometric observations of the inner regions of two A-star debris disks, beta Leo and zeta Lep, using the FLUOR instrument at the CHARA interferometer on both short (30 m) and ... [more ▼]

We present infrared interferometric observations of the inner regions of two A-star debris disks, beta Leo and zeta Lep, using the FLUOR instrument at the CHARA interferometer on both short (30 m) and long (> 200 m) baselines. For the target stars, the short-baseline visibilities are lower than expected for the stellar photosphere alone, while those of a check star, delta Leo, are not. We interpret this visibility offset of a few percent as a near-infrared (NIR) excess arising from dust grains which, due to the instrumental field of view, must be located within several AU of the central star. For beta Leo, the NIR excess-producing grains are spatially distinct from the dust which produces the previously known mid-infrared (MIR) excess. For zeta Lep, the NIR excess may be spatially associated with the MIR excess-producing material. We present simple geometric models which are consistent with the NIR and MIR excesses and show that for both objects, the NIR-producing material is most consistent with a thin ring of dust near the sublimation radius, with typical grain sizes smaller than the nominal radiation pressure blowout radius. Finally, we discuss possible origins of the NIR-emitting dust in the context of debris disk evolution models. [less ▲]

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See detailGJ 436c? The contribution of transit timings
Demory, B*-O; Gillon, Michaël ULg; Waelkens, C. et al

in IAU Symposium 253: Transiting planets (2009, February 01)

From recent high-accuracy transit timings measurements, we discard the 5 M_earth planet recently proposed by Ribas et al. (2008). Thanks to a combined radial-velocity and transit timings overview we also ... [more ▼]

From recent high-accuracy transit timings measurements, we discard the 5 M_earth planet recently proposed by Ribas et al. (2008). Thanks to a combined radial-velocity and transit timings overview we also define a mass/period domain in which a secondary planet may be found in the system. We also show that timings obtained until now, although not sufficient to remove degeneracies on mass and period, can still restrict the parameter space of the potential secondary planet. [less ▲]

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See detailTransits against Fainter Stars: The Power of Image Deconvolution
Sackett, Penny D; Gillon, Michaël ULg; Bayliss, Daniel D R et al

in IAU Symposium 253: Transiting planets (2009, February 01)

Compared to bright star searches, surveys for transiting planets against fainter (V = 12 18) stars have the advantage of much higher sky densities of dwarf star primaries, which afford easier detection of ... [more ▼]

Compared to bright star searches, surveys for transiting planets against fainter (V = 12 18) stars have the advantage of much higher sky densities of dwarf star primaries, which afford easier detection of small transiting bodies. Furthermore, deep searches are capable of probing a wider range of stellar environments. On the other hand, for a given spatial resolution and transit depth, deep searches are more prone to confusion from blended eclipsing binaries. We present a powerful mitigation strategy for the blending problem that includes the use of image deconvolution and high-resolution imaging. The techniques are illustrated with Lupus-TR-3 and very recent IR imaging with PANIC on Magellan. The results are likely to have implications for the CoRoT and KEPLER missions designed to detect transiting planets of terrestrial size. [less ▲]

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See detailEngagements Pédagogiques Chimie Bac 1 ‘Sciences de la Vie’
Focant, Jean-François ULg

Learning material (2009)

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See detailLe droit de la lutte contre la discrimination dans tous ses états
Wautelet, Patrick ULg

Book published by Anthemis - Collection Commission Université Palais (2009)

This books offers an overview of the scheme put in place with the twin Anti-Discrimination Acts adopted by the Belgian Federal legislator on 10 May 2007. After a general overview of the basic concepts, a ... [more ▼]

This books offers an overview of the scheme put in place with the twin Anti-Discrimination Acts adopted by the Belgian Federal legislator on 10 May 2007. After a general overview of the basic concepts, a detailed analysis of the practical consequences of the antidiscrimination regime is offered in the insurance sector, the housing sector and finally in banking and financial relationships. In a final chapter, some attention is devoted to the specific civil sanctions put in place by the legislator. [less ▲]

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See detailHOW TO MAKE NATURA 2000 WORK PROPERLY? : SOCIO-ECONOMIC, LEGAL AND ECOLOGICAL MANAGEMENT : "SELNAT"
Grogna, Valérie; Mahy, Marie; Meuris, Steve et al

Report (2009)

This report includes results obtained from the SELNAT research project, conducted between February 2006 and January 2008, under the auspices of the Belgian Science Policy. The principal subject of this ... [more ▼]

This report includes results obtained from the SELNAT research project, conducted between February 2006 and January 2008, under the auspices of the Belgian Science Policy. The principal subject of this project is the implementation of Natura 2000. The Natura 2000 network of protected areas, made up of sites designated under the Community Birds (BD) and Habitats Directives (HD), is a key pillar of action for the conservation of biodiversity (European Commission, 2008). It is central to achieve the commitment to reverse the decline of biodiversity in the European Union by the year 2010 made at the European Council meeting in Gothenburg in June 2001. It aims at sustainable conservation of habitats and species of community importance, taking into account (i) economic, social and cultural requirements and (ii) regional and local circumstances. Central to the Directives is the creation of a Europe-wide ecological network of protected sites – the Natura 2000 Network – which is destined to conserve over a thousand rare, threatened and endemic species and some 220 Natural habitats listed in their annexes. Around 24,000 sites have been included in the Network so far. (European Commission, 2008) Now that the network set-up is nearing completion, there is a need to increase the focus on the active management of the sites so as to ensure long-term conservation and the achievement of the economic and social objectives of the network (CEE, 2004.) This in turn also raises the question of finding the appropriate management strategy, instruments and sufficient financing (at all levels). The principal question for Member States is how to manage Natura 2000 sites to reach the (juridical fixed) ecological targets in the most cost-efficient way, taking into account economic and social objectives and constraints. Ecologists and nature organisations often start from an techno-ecocentric paradigm: ‘How to conserve and manage species and habitats?’, in order to tackle the question mentioned above. The paradigm starts from the opinion that ‘diversity of species and habitats’ is important as such (while this is believed to be important for several reasons). This approach has been criticised lately for being based on a too narrow set of values. It has not provided enough opportunities for combining nature conservation with other forms of land use such as agriculture, forestry or tourism. In several countries this led to difficulties as regards the co-operation of local stakeholders (Jongman & Kristiansen, 1998). On the other hand, the current biodiversity crisis is a direct result of the way in which society has chosen to interact with its Natural environment. If the causes of the problem are social, it stands to reason that the policies striving to solve the problem will need to be based on a solid understanding of social structures and processes, if they are to have any effect. In this research project we tried to study the management of Natura 2000 sites from a ‘sustainability’ paradigm, instead of from the ecocentric paradigm. The central research question is therefore formulated as ‘How to manage Natura 2000 properly, to contribute to a (local) sustainable society?’ With this research we hope to give decision-makers new insights on the economic, social, and environmental consequences of Natura 2000 management and to guide them in the development of more adequate and sustainable policies for the management of Natura 2000-sites. In the first chapter the general objectives and approach of this project are described. The second chapter gives an overview of some of the current bottlenecks for nature conservation and Natura 2000. The results of the research on the elaboration of strategies for Natura 2000 sites are summarizes in chapter tree. Conclusions and recommendations are presented in the last chapter. More information on the research is documented in the different appendixes. During the research, we benefited from contacts with many persons, and more especially in the scope of a Users’ Committee. Besides the representatives of the Belgian Science Policy, we would like to thank all members of the Users’ Committee, among which those who supported us and/or participated in one or several of the meetings, [less ▲]

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See detailLes strategies juridiques en droit des coordinations entre entreprises Une approche scenarisee
Petit, Nicolas ULg

in Masson, A. (Ed.) Les stratégies juridiques des entreprises (2009)

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See detailCharacterising and Exploiting Workloads of Highly Interactive Video-on-Demand
Brampton, Andrew; MacQuire, Andrew; Fry, Michael et al

in Multimedia Systems (2009)

This paper presents a detailed character- isation of user behaviour for a series of interactive video experiments over a 12 month period, in which we served popular sporting and musical content. In ad ... [more ▼]

This paper presents a detailed character- isation of user behaviour for a series of interactive video experiments over a 12 month period, in which we served popular sporting and musical content. In ad- dition to generic VCR-like features, our custom-built Video-on-Demand application provides advanced inter- activity features such as bookmarking. The dramatic impact of such functionality on how users consume con- tent is studied and analysed. We discuss in detail how this user behaviour can be exploited by content dis- tributors to improve user experience. Speci cally, we study how simple dynamic bookmark placement and interactivity-aware content pre-fetching and replication can reduce the impact of highly interactive media on CDN performance. [less ▲]

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See detailPHC: Why now more than ever?
Porignon, Denis ULg

Conference given outside the academic context (2009)

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See detailImportance of pigtailed macaques (Macaca nemestrina leonina) in seed dispersal and impact on the ecological balance of the tropical rainforest at Khao Yai National Park, Thailand
Albert, Aurélie ULg; Huynen, Marie-Claude ULg

Poster (2009, February)

The tropical rain forest is maintained thanks to a precarious balance placed under the yoke of interactions between the various animal and plant species which compose it. Among them we can find those ... [more ▼]

The tropical rain forest is maintained thanks to a precarious balance placed under the yoke of interactions between the various animal and plant species which compose it. Among them we can find those implying plants and frugivores. Although its diet is largely frugivorous, the pigtailed macaques (Macaca nemestrina leonina) have often been categorized as seed predators. However their morphology, behaviour and ecology suggest they could actually be a key-species in the dispersion of many plant species. A preliminary study by Latinne & al (2007) supported this hypothesis. The study we are planning now in continuity of Latinne’s study will take place in the Khao Yai National Park, Thailand, for three years and will focus on a troop habituated to humans. In order to establish the importance of the pigtailed macaques in the maintenance and the regeneration of the tropical rain forest, we will try to evaluate their capacity of being good seed dispersers. To do so, we will study: 1) the spatiotemporal distribution, the productivity and the characteristics of the plant species present on the home range of the studied troop, 2) the ranging patterns of the macaques within their home range, 3) their feeding behaviour, notably the fruit selection and the various modes of processing seeds, and finally 4) their impact on the viability and the germination potential of seeds. This study will require both direct observations of the macaques and semi-experimental procedures in the field, as well as laboratory control of some seed parameters. We hope the clarification of the macaques’ seed dispersal behaviour would help to re-evaluate their conservation status by recognizing them a paramount role in the maintenance of the tropical rainforest. [less ▲]

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See detailLe cas clinique du mois. Transplantation hépatique pour un hémangio-endothéliome épithélioïde du foie
Tonglet, M.; Delfosse, V.; Detry, Olivier ULg et al

in Revue Médicale de Liège (2009), 64(2), 68-70

L’hémangioendothéliome épithélioïde est une affection maligne rare qui peut survenir dans le foie. Lorsque la forme est multifocale et bilobaire, la transplantation hépatique constitue le traitement ... [more ▼]

L’hémangioendothéliome épithélioïde est une affection maligne rare qui peut survenir dans le foie. Lorsque la forme est multifocale et bilobaire, la transplantation hépatique constitue le traitement curateur de cette affection. Dans cet article, les auteurs décrivent le diagnostic et le traitement d’une femme de 52 ans souffrant d’un hémangioendothéliome épithélioïde hépatique traitée par transplantation du foie. [less ▲]

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See detailDashboard aimed at decision-makers and citizens in place managmenent, within SD principles
De Graef, Sarai; Dalimier, Isabelle; Ericx, Michel et al

Report (2009)

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See detailLe cahier de santé de votre enfant
Battisti, Oreste ULg

Learning material (2009)

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See detailA multiwavelength investigation of the massive eclipsing binary Cyg OB2 #5
Linder, Natacha ULg; Rauw, Grégor ULg; Manfroid, Jean ULg et al

in Astronomy and Astrophysics (2009), 495

Context. The properties of the early-type binary Cyg OB2 #5 have been debated for many years and spectroscopic and photometric investigations yielded conflicting results. Aims. We have attempted to ... [more ▼]

Context. The properties of the early-type binary Cyg OB2 #5 have been debated for many years and spectroscopic and photometric investigations yielded conflicting results. Aims. We have attempted to constrain the physical properties of the binary by collecting new optical and X-ray observations. Methods. The optical light curves obtained with narrow-band continuum and line-bearing filters are analysed and compared. Optical spectra are used to map the location of the He II $\lambda $ 4686 and H$\alpha $ line-emission regions in velocity space. New XMM-Newton as well as archive X-ray spectra are analysed to search for variability and constrain the properties of the hot plasma in this system. Results. We find that the orbital period of the system slowly changes though we are unable to discriminate between several possible explanations of this trend. The best fit solution of the continuum light curve reveals a contact configuration with the secondary star being significantly brighter and hotter on its leading side facing the primary. The mean temperature of the secondary star turns out to be only slightly lower than that of the primary, whilst the bolometric luminosity ratio is found to be 3.1. The solution of the light curve yields a distance of $925 \pm 25$ pc much lower than the usually assumed distance of the Cyg OB2 association. Whilst we confirm the existence of episodes of higher X-ray fluxes, the data reveal no phase-locked modulation with the 6.6 day period of the eclipsing binary nor any clear relation between the X-ray flux and the 6.7 yr radio cycle. Conclusions. The bright region of the secondary star is probably heated by energy transfer in a common envelope in this contact binary system as well as by the collision with the primary's wind. The existence of a common photosphere probably also explains the odd mass-luminosity relation of the stars in this system. Most of the X-ray, non-thermal radio, and possibly $\gamma$-ray emission of Cyg OB2 #5 is likely to arise from the interaction of the combined wind of the eclipsing binary with at least one additional star of this multiple system. [less ▲]

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See detailPrise en charge de l'insuffisance rénale chronique à l’occasion de la journée Mondiale du rein Jeudi 13 mars 2008
Krzesinski, Jean-Marie ULg

in Revue Médicale de Liège (2009), 64(2), 71-72

Chronic kidney disease is a worldwide growing problem, especially due to three factors very often encountered together (old age, diabetes mellitus and arterial hypertension). A multidisciplinary approach ... [more ▼]

Chronic kidney disease is a worldwide growing problem, especially due to three factors very often encountered together (old age, diabetes mellitus and arterial hypertension). A multidisciplinary approach is needed to reduce this epidemic that has important health implications.This needs of course well trained health partners. On the occasion of the world kidney day on March 2008, four lectures were given, which gave an updated overview of the management of chronic kidney insufficiency, a serious problem of public health. [less ▲]

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See detailPluridisciplinarité, continuité et qualité des soins en 1ère ligne : quelles attentes des professionnels ?
Vanmeerbeek, Marc ULg; Duchesnes, Christiane ULg; Massart, Valérie ULg et al

Report (2009)

Le GLS souhaite établir son plan d’action pour les années à venir à la lumière de l’opinion des professionnels des soins à domicile. La présente étude du Département de Médecine Générale de l’Université ... [more ▼]

Le GLS souhaite établir son plan d’action pour les années à venir à la lumière de l’opinion des professionnels des soins à domicile. La présente étude du Département de Médecine Générale de l’Université de Liège a permis de donner la parole à une centaine d’acteurs de la première ligne, répartis au sein de six professions différentes. Les deux outils de recueils de données que sont les Groupes focalisés et les Groupes nominaux donnent logiquement des informations de natures différentes. Les usages concrets qui peuvent en être faits sont également différents. Il existe naturellement de très larges superpositions qui font que les discours entendus sont cohérents. Les FG ont exploré de manière très détaillée les ressentis, les représentations et les attentes individuels de professionnels des soins à domicile vis-à-vis des missions attribuées aux Services Intégrés de Soins à Domicile. Globalement, c’est l’état d’esprit des professionnels qui a été visité dans les deux domaines importants que sont la qualité des soins et le travail collaboratif. Il en ressort de grandes tendances qu’il peut être utile d’identifier pour une structure comme le GLS. Les réalités des soins à domicile sont analysées de manière assez homogène ; la complexité médicosociale de certaines situations est évidente aux yeux de tous et la plus-value apportée par l’action pluridisciplinaire dans de telles circonstances est spontanément évoquée par tous. Les différentes disciplines tiennent un discours assez unanime sur la nécessité de centrer son attention sur le patient qui doit devenir un acteur de ses propres soins. Un changement de modèle qui fait passer le patient d’une situation passive à une position active est en train de s’opérer. La culture pluridisciplinaire fait son chemin, elle progresse malgré des obstacles bien reconnus par les prestataires des différentes disciplines. En définitive, la prise en charge de soins à domicile suscite un riche questionnement éthique où se mêlent des interrogations sur la place du patient, sur la pluridisciplinarité et le partage des informations professionnelles, sur la gestion des situations complexes, sur le développement professionnel et personnel des soignants, sur la place des soins à domicile dans notre système de santé. La contribution des SISD peut être importante dans ces vastes domaines de réflexion : on peut penser à des colloques, des formations, des rencontres pluridisciplinaires,… Plus spécifiquement, les FG ont permis d’identifier des préoccupations plus particulières qui interpellent toutes les disciplines et qui pourraient déboucher sur des actions concrètes. On peut ainsi épingler, dans le désordre, le besoin de soutien au bien-être des soignants, la demande de programmes de formation pluridisciplinaire, le souhait implicite d’outils novateurs en matière d’échanges d’informations, l’intérêt exprimé pour toute initiative locale favorisant les contacts pluridisciplinaires et la connaissance des autres disciplines. Le discours des soignants permet également de relever des carences qui ne sont pas spontanément exprimées : méconnaissance des dispositifs sociaux améliorant l’accessibilité aux soins et leur coût, de la législation relative à la concertation multidisciplinaire, du rôle des centres de coordination et des coordinatrices de soins. Ici encore des actions d’information peuvent être initiées ou poursuivies. Les GN nous apportent un éclairage plus concret sur les actions qui peuvent être menées pour favoriser le développement du travail collaboratif et améliorer l’action pluridisciplinaire. En outre, cette méthode permet une hiérarchisation des propositions tout en autorisant que soient révélées des sensibilités propres à chaque discipline. De grands domaines d’actions prioritaires, identifiés par toutes les disciplines, peuvent se dégager : les rencontres entre professionnels, les moyens de communication interdisciplinaires et l’organisation concrète de l’action pluridisciplinaire locale. Les indices de priorité et de popularité permettent d’approcher, pour chaque action envisageable, l’importance que les professionnels lui accordent ainsi que le nombre de ceux qui pourraient être intéressés. Au départ des grandes catégories ou sous-catégories d’actions, la méthode des GN a l’avantage de permettre de retourner aux propositions précises, telles qu’exprimées et validées par les professionnels. [less ▲]

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See detailLa prise en charge de l'insuffisance rénale chronique avant la dialyse
Smelten, Nicole; Krzesinski, Jean-Marie ULg

in Revue Médicale de Liège (2009), 64(2), 79-85

Chronic renal failure is usually a silent disease until its late stage, especially in elderly people. Screening for such disease is particularly useful in hypertensive diabetic patients above 50 years ... [more ▼]

Chronic renal failure is usually a silent disease until its late stage, especially in elderly people. Screening for such disease is particularly useful in hypertensive diabetic patients above 50 years. The causes are indeed often vascular or metabolic (directly or not directly linked to diabetes mellitus). Other less frequent causes are yet possible. The search for the right diagnosis of renal insufficiency is always requested to apply the appropriate treatment, combined with medical measures for secondary and tertiary prevention. This review will give general advices to avoid the development of renal disease (stages 3 and 4) or its progression, and also insist on the potential nephrotoxic effects of some drugs. [less ▲]

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See detailAutonomous rigid body attitude synchronization
Sarlette, Alain ULg; Sepulchre, Rodolphe ULg; Leonard, Naomi

in Automatica (2009), 45(2), 572-577

Control laws to synchronize attitudes in a swarm of fully actuated rigid bodies, in the absence of a common reference attitude or hierarchy in the swarm, are proposed in [Smith, T. R., Hanssmann, H ... [more ▼]

Control laws to synchronize attitudes in a swarm of fully actuated rigid bodies, in the absence of a common reference attitude or hierarchy in the swarm, are proposed in [Smith, T. R., Hanssmann, H., & Leonard, N.E. (2001). "Orientation control of multiple underwater vehicles with symmetry-breaking potentials". In Proc. 40th IEEE conf. decision and control (pp. 4598–4603); Nair, S., Leonard, N. E. (2007). "Stable synchronization of rigid body networks". In Networks and Heterogeneous Media, 2(4), 595–624]. The present paper studies two separate extensions with the same energy shaping approach: (i) locally synchronizing the rigid bodies’ attitudes, but without restricting their final motion and (ii) relaxing the communication topology from undirected, fixed and connected to directed, varying and uniformly connected. The specific strategies that must be developed for these extensions illustrate the limitations of attitude control with reduced information. [less ▲]

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See detailL’étude ACCOMPLISH : remise en question des choix médicamenteux chez les patients hypertendus systoliques à haut risque cardio-vasculaire
Krzesinski, Jean-Marie ULg; Scheen, André ULg

in Revue Médicale de Liège (2009), 64(2), 103-108

Arterial hypertension is an important cardiovascular risk factor. The benefit drawn from decreasing and normalizing the blood pressure level is indisputable. The ACCOMPLISH study performed in patients ... [more ▼]

Arterial hypertension is an important cardiovascular risk factor. The benefit drawn from decreasing and normalizing the blood pressure level is indisputable. The ACCOMPLISH study performed in patients older than 65 with systolic hypertension and a high cardiovascular risk pointed out the interest of well choosing the antihypertensive combination to reduce this risk beyond the decrease of blood pressure. The association of benazepril (an angiotensin converting enzyme inhibitor or ACEI) and amlodipine (a calcium antagonist) has shown significant early cardiovascular protection in such patients as compared to the classic association including the same ACEI and hydrochlorothiazide, in spite of the same target blood pressure reached. This important finding does not contest the interest of a well controlled blood pressure in hypertension, but probably will modify our first antihypertensive combination choice in the future in patients with such cardiovascular profile. [less ▲]

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