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See detailLocal search heuristics for large-scale discrete structural optimization with expensive black-box evaluations
Bay, Maud ULg; Crama, Yves ULg; Rigo, Philippe ULg

Report (2009)

This paper considers large-scale structural optimization problems featuring discrete variables, as well as nonlinear implicit constraints which can only be evaluated through time-expensive computations. A ... [more ▼]

This paper considers large-scale structural optimization problems featuring discrete variables, as well as nonlinear implicit constraints which can only be evaluated through time-expensive computations. A prominent application consists in the preliminary structural design of large ships, where many of the variables take their values in discrete sets which model standard element dimensions to be selected from catalogs, and where the evaluation of the constraints involves a complex structural analysis performed by black-box software. The resulting large-scale nonlinear combinatorial problems are particularly hard, and even nding a discrete feasible solution may prove challenging for some instances. In this paper, we propose two heuristics that combine local search methods and a sequential optimization method based on approximations of the implicit constraints. The heuristics are applied to the structural optimization of several large ships. For these instances, the heuristics provide discrete feasible solutions whose value is close to the optimal value of the continuous relaxation obtained by disregarding the discrete nature of the variables. [less ▲]

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See detailFraming the "Clash of Civilizations" in Europe: Interaction between Political and Media Frames
La Porte, María Teresa; Azpíroz Manero, María Luisa ULg

in Journal of Media and Communication Studies (2009), 1(1), 011-022

The present study reviews the foci, symbols and interpretations that the European media use to formulate and spread the political message about the “clash of civilizations”. This means observing how this ... [more ▼]

The present study reviews the foci, symbols and interpretations that the European media use to formulate and spread the political message about the “clash of civilizations”. This means observing how this cultural clash is articulated in political discourse and how this is then reflected in the leading European media. To carry out this study, we compared the frames found in several significant political discourses (Bush, Ahmadinejad, Sarkozy, Gül) and those encountered in the coverage of these same discourses in the following European newspapers: The Guardian, Le Monde, Frankfürter Allemaigne. Through this specific case, the research also explores what is the process of the frame elaboration and which conditions make political discourse more effective and attractive for the media to assimilate them. [less ▲]

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See detailLes ichthyosaures du sud-­est de la France
Fischer, Valentin ULg

Master's dissertation (2009)

The examination of the ichthyosaur collections housed at the “Réserve géologique de Haute-Provence” (RGHP, High-Provence Alps, South-East France) brings new data on the ecology and diversity of Jurassic ... [more ▼]

The examination of the ichthyosaur collections housed at the “Réserve géologique de Haute-Provence” (RGHP, High-Provence Alps, South-East France) brings new data on the ecology and diversity of Jurassic and Cretaceous ichthyosaurs. The specimens of this collection all come from the Vocontian Trough, a deep Mesozoic basin lying at the North-western border of Tethys, making this area the southernmost European locality where diagnostic ichthyosaurs have been found. However, faunal assemblages found in the Vocontian Basin are identical to other European assemblages, especially during Toarcian (Lower Jurassic). Of particular interest is the presence of the Toarcian genus Suevoleviathan, recorded for the first time outside of the German basins. Every Toarcian ichthyosaur genus is now found in at least two European basins, seriously questioning Toarcian ichthyosaur endemism, at least at the genus level. This specimen has been found along with Eurhinosaurus longirostris and several Thunnosauria indet. aff. Stenopterygius. It is shown that the Toarcian ichthyosaur “endemism” is most probably an effect of preservational biases. Aside from their geographic remoteness compared to the typical ichthyosaur localities, the stratigraphic position of the RGHP specimens is also particularly interesting, especially during the Cretaceous: the first diagnostic ichthyosaur clearly belonging to Valanginian strata is described here. This specimen turned out to be assignable to Aegirosaurus leptospondylus, a species previously known only from the Tithonian lithographic limestones of Bavaria (Bardet & Fernández, 2000). Three Albian specimens are also described. One of them is referable to the cosmopolitan genus Platypterygius, while the two others belong to a new taxon, with tiny pointed teeth. This suggests that new taxon marks the colonization of a new ecological niche during the Albian. This has two major implications: firstly the Vocontian basin can now be regarded as one of the best Cretaceous ichthyosaur-bearing localities of the world in terms of ecologic diversity. Secondly, the effect of the Jurassic-Cretaceous boundary extinction (JCB) on post-liassic ichthyosaurs is weak: their diversity remains nearly constant during JCB and up to the Albian. On the contrary the Cenomanian-Turonian boundary extinction seemed to be far more severe than the simple “knock on the head” of a group on the decline since the Middle Jurassic, as seen in the literature. [less ▲]

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See detailImpact and potential of community scale low-energy retrofit: case study in Cairo
Attia, Shady ULg; De Herde, André

in Proceedings of the 3rd CIB International Conference on Smart and Sustainable Built Environment (2009, June)

There are extraordinary opportunities to reduce the consumption of fossil energy as a result of retrofitting the existing buildings in Egypt. For instance, Cairo falls in the arid climate zone with an ... [more ▼]

There are extraordinary opportunities to reduce the consumption of fossil energy as a result of retrofitting the existing buildings in Egypt. For instance, Cairo falls in the arid climate zone with an annual total radiation above 2409 bankable kWh/m2 per annum with approximately 3300 hours of full sunshine. However, the poorly insulated fabric of most buildings shows relatively high demand for cooling and heating energy. To overcome this problem and to examine these opportunities, this study evaluates the retrofit of a middle-income urban residential case in Cairo. The aim of the study is to investigate the potential and impact of retrofits on two different scales. The first is on the building scale, intending to reach a low-energy performance. The second is on a community scale, intending to increase the dependence on renewable sources. The case study employed TRNSYS to evaluate the performance and energy/carbon emissions savings. The research took in consideration passive and active design strategies such as envelope retrofit, internal loads reduction, and natural ventilation; in addition to domestic water heating, photovoltaic panels and solar thermal air conditioning. The results were evaluated to assess the suitability of each strategy based on energy performance. The final result of this study shows the feasibility of improving the envelope performance and installing solar hot water collectors and solar thermal air conditioning. The low-energy retrofit for old residential buildings leads to significant savings in energy consumption when applied on community scale rather than building scale. However, it is urgent to set energy conservation and code-enforced retrofit measures to start a national retrofit process. [less ▲]

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See detailUniversal solid support synthesis of modified oligonucleotides labeled by click chemistry for PET studies
Flagothier, Jessica ULg; Mercier, Frederic; Kaisin, Geoffroy ULg et al

Poster (2009, May 29)

Introduction: Positron emission tomography (PET) is a high-resolution, sensitive, molecular and functional imaging technique that permits repeated, non invasive assessment and quantification of specific ... [more ▼]

Introduction: Positron emission tomography (PET) is a high-resolution, sensitive, molecular and functional imaging technique that permits repeated, non invasive assessment and quantification of specific biological and pharmacological processes in humans[1]. In regard to its physical and nuclear characteristics, fluorine-18 appears often as the radionuclide of choice for the preparation of short-lived positron-emitter radiotracers[2]. F-18 labelling reaction of biomolecules such as peptides[3], oligosaccharides, and oligonucleotides[4] (ONs) requires very mild reaction conditions. The method of choice for a highly efficient fluorine-18-labelling of ONs is today the conjugation of a prosthetic group, carrying the radioisotope, with a reactive function of the ONs. Methods: For the ligation reaction of the prosthetic group with the ONs, we selected click reaction and more particularly the CuI catalyzed formation of 1,2,3-triazole using Huisgen 1,3-dipolar cycloaddition of terminal alkynes with azides. This reaction is highly regioselective leading to 1,4-disubstituted 1,2,3-triazoles and can be performed in different solvents with very high yield[5-7]. Conjugations with ONs are usually performed at 3’-ends using a well chosen linker in order to limit degradation by exonucleases[8]. Here we report the synthesis of an alkyne-bearing linker which can be attached at 3’-ends to any sequence of ONs. Results: The linker was prepared in two steps by reaction of commercially available (R)-(+)--hydroxy--butyrolactone with propargylamine followed by protection of the primary hydroxyl with the 4,4’-dimethoxytrityl group[9]. The second step is the reaction with succinic anhydride to obtain a carboxylic function which can be attached to the Amino-SynBase CPG. The resin load was 80 µmol/g. Conclusions: We have prepared a new universal linker which allows introducing an alkyne function at the 3’-end of ONs. This alkyne modified ONs can then react under click conditions with an azide function of a prosthetic group carrying the fluorine radioisotope. As prosthetic group, we selected the 1-azido-4-(3-[18F]fluoropropoxy)benzene which is fully automated produce in our lab[10]. The further results of radiosynthesis of this prosthetic group and the results of click reactions will be presented. Acknowledgement: The authors wish to thank Teller N. from Eurogentec (Seraing, Belgium) for oligonucleotide synthesis. The authors wish to acknowledge the financial support from the Oligopet Projet of the Walloon Region. [less ▲]

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See detailNouveaux outils de diagnostic in-vitro des allergies
Gadisseur, Romy ULg; Chapelle, Jean-Paul ULg; Cavalier, Etienne ULg

Conference (2009, May 29)

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See detailGBS Training Course Specimen collection and culture procedure
Melin, Pierrette ULg

Scientific conference (2009, May 29)

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See detailLe travail peut-il rendre malade?
Triffaux, Jean-Marc ULg

Conference given outside the academic context (2009)

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See detailVaricella vaccination in Europe – taking the practical approach
Bonanni, Paolo; Breuer, Judith; Gershon, Anne A. et al

in BMC Medicine (2009), 7(26), 1-38

Varicella is a common viral disease affecting almost the entire birth cohort. Although usually self-limiting, some cases of varicella can be serious, with 2 to 6% of cases attending a general practice ... [more ▼]

Varicella is a common viral disease affecting almost the entire birth cohort. Although usually self-limiting, some cases of varicella can be serious, with 2 to 6% of cases attending a general practice resulting in complications. The hospitalisation rate for varicella in Europe ranges from 1.3 to 4.5 per 100,000 population/year and up to 10.1% of hospitalised patients report permanent or possible permanent sequelae (for example, scarring or ataxia). However, in many countries the epidemiology of varicella remains largely unknown or incomplete. In countries where routine childhood vaccination against varicella has been implemented, it has had a positive effect on disease prevention and control. Furthermore, mathematical models indicate that this intervention strategy may provide economic benefits for the individual and society. Despite this evidence and recommendations for varicella vaccination by official bodies such as the World Health Organization, and scientific experts in the field, the majority of European countries (with the exception of Germany and Greece) have delayed decisions on implementation of routine childhood varicella vaccination, choosing instead to vaccinate high-risk groups or not to vaccinate at all. In this paper, members of the Working Against Varicella in Europe group consider the practicalities of introducing routine childhood varicella vaccination in Europe, discussing the benefits and challenges of different vaccination options (vaccination vs. no vaccination, routine vaccination of infants vs. vaccination of susceptible adolescents or adults, two doses vs. one dose of varicella vaccine, monovalent varicella vaccines vs. tetravalent measles, mumps, rubella and varicella vaccines, as well as the optimal interval between two doses of measles, mumps, rubella and varicella vaccines). Assessment of the epidemiology of varicella in Europe and evidence for the effectiveness of varicella vaccination provides support for routine childhood programmes in Europe. Although European countries are faced with challenges or uncertainties that may have delayed implementation of a childhood vaccination programme, many of these concerns remain hypothetical and with new opportunities offered by combined measles, mumps, rubella and varicella vaccines, reassessment may be timely. In countries where routine childhood vaccination against varicella has been implemented, it has had a positive effect on disease prevention and control. Furthermore, mathematical models indicate that this intervention strategy may provide economic benefits for the individual and society. Despite this evidence and recommendations for varicella vaccination by official bodies such as the World Health Organization, and scientific experts in the field, the majority of European countries (with the exception of Germany and Greece) have delayed decisions on implementation of routine childhood varicella vaccination, choosing instead to vaccinate high-risk groups or not to vaccinate at all. In this paper, members of the Working Against Varicella in Europe group consider the practicalities of introducing routine childhood varicella vaccination in Europe, discussing the benefits and challenges of different vaccination options (vaccination vs. no vaccination, routine vaccination of infants vs. vaccination of susceptible adolescents or adults, two doses vs. one dose of varicella vaccine, monovalent varicella vaccines vs. tetravalent measles, mumps, rubella and varicella [MMRV] vaccines, as well as the optimal interval between two doses of MMRV vaccines). Assessment of the epidemiology of varicella in Europe and evidence for the effectiveness of varicella vaccination provides support for routine childhood programmes in Europe. Although European countries are faced with challenges or uncertainties that may have delayed implementation of a childhood vaccination programme, many of these concerns remain hypothetical and with new opportunities offered by combined MMRV vaccines, reassessment may be timely. [less ▲]

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See detailTesting of Expanded Metal Sheets under Cyclic Shear Loadings
Phung Ngoc, Dung ULg; Degée, Hervé ULg; Plumier, André ULg

in National Conference of Theoretical and Applied Mechanics (2009)

Abstract: With the aims at determining the mechanical properties of Expanded Metal Sheet under seismic excitations, the research on Expanded Metal Sheet has been implementing at University of Liege ... [more ▼]

Abstract: With the aims at determining the mechanical properties of Expanded Metal Sheet under seismic excitations, the research on Expanded Metal Sheet has been implementing at University of Liege. Firstly, the square and rectangular sheets worked in monotonic shear loading was thoroughly studied by E.Pecquet[1]. In his study, there are three approaches used to determine the mechanic behavior of expanded metal sheets monotonically loaded in shear, that is, analytical models, numerical simulations and experimental investigations were performed and compared simultaneously. Secondly, the same dimensions of the sheets will be studied under cyclic shear loading. In this research, non-linear numerical stimulations and experimental investigation will be used to determine the properties of expanded metal sheets under cyclic shear loads. The analytical models will be proposed with the aims at modeling the sheets in Reinforced Concrete Frames, the next step of this study. Numerical stimulations are implemented with FINELG, a non linear finite element code. Expanded Metal Sheet Experiments under reverse loading are to be carried out at Laboratory of University of Liege. Experimental Investigations will be compared with numerical stimulations to propose an analytical model, hysteric loop for this type of material under cyclic loading. [less ▲]

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See detailUne approche reposante (RESTful) des aspects opérationnels de la rétroconversion du Französisches Etymologisches Wörterbuch (FEW)
Briquet, Cyril; Renders, Pascale ULg

Conference (2009, May 28)

Les articles du Französisches Etymologisches Wörterbuch (FEW) seront bientôt enrichis d'un balisage (XML) sémantique par une séquence d'algorithmes. Nous proposons un modèle éditorial distribué (“à la ... [more ▼]

Les articles du Französisches Etymologisches Wörterbuch (FEW) seront bientôt enrichis d'un balisage (XML) sémantique par une séquence d'algorithmes. Nous proposons un modèle éditorial distribué (“à la Wikipedia”) des corrections manuelles à apporter aux articles qui ne peuvent être automatiquement balisés. En outre, de manière à rendre totalement transparent pour les contributeurs le maintien de la consistance et de la synchronisation des trois quarts de million de documents considérés, nous proposons une plate-forme web de rétroconversion basée sur une architecture logicielle reposante (RESTful, cf. article Wikipedia sur REST). [less ▲]

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See detailConception d'algorithmes de rétroconversion
Renders, Pascale ULg; Briquet, Cyril

Conference (2009, May 28)

Rétroconvertir un ouvrage imprimé consiste à le transformer, de la manière la plus automatisée possible, en un ouvrage informatisé. Dans le cas d'un dictionnaire tel que le Französisches Etymologisches ... [more ▼]

Rétroconvertir un ouvrage imprimé consiste à le transformer, de la manière la plus automatisée possible, en un ouvrage informatisé. Dans le cas d'un dictionnaire tel que le Französisches Etymologisches Wörterbuch (FEW), il s'agit en outre de l'enrichir d'un balisage XML qui permette des consultations ciblées. Le noyau de l'opération est constitué de 37 algorithmes dits "de rétroconversion" qui balisent chacun un type d'information "cible" du dictionnaire. Cet article présente, en guise d'exemple, la mise au point de l'algorithme qui reconnaît et balise le(s) signataire(s) d'un article du FEW. [less ▲]

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See detailContribution à l’étude de l’activité antivirale et du mécanisme moléculaire de la MX1 bovine
Baise, Etienne ULg

Doctoral thesis (2009)

Summary Type I interferons (IFNs a/b) induce the synthesis of many factors belonging to the innate immune system which is known to play an essential role as the first defence line against the viral ... [more ▼]

Summary Type I interferons (IFNs a/b) induce the synthesis of many factors belonging to the innate immune system which is known to play an essential role as the first defence line against the viral infection. Among these contributors, the MX protein (a member of the large GTPase family) along with the double stranded (ds) RNA dependent protein kinase R (PKR) and the 2’5’ oligoadenylate synthetase/Rnase L system, has been shown to be one of the most efficient among the murine and the human species. The bovine counterpart of the MX system was, at the beginning of this work, described at the sole gene level (the CDS sequence) but its functional capacity was still totally unexplored. Accordingly, our first aim was to assess the ability of the bovine GTPase we called boMX1 to inhibit viruses infecting cattle. A Vero cell line (V103) conditionally expressing the boMX1 was established. To proof the concept, we firstly tested the inhibition of a canonical virus on this field, the vesicular stomatitis virus (VSV) which was confirmed to be as sensitive to boMX1 as previously shown to MXA (Homo sapiens). In a second step, we focused our investigation on the activity of boMX1 against two Paramyxoviridae viruses, the boRSV and the boPI3, both of these being sensitive to IFNs as reported in the literature and furthermore confirmed by our previous in vitro experiments. Although boMX1 was expected to be the most important factor of the type I interferon resistance recorded against boPI3 and boRSV, our study has shown that the bovine protein was not able to block these viruses belonging to the Respirovirus genus. Conversely, the famous Orthomyxoviridae virus member, Influenza A was shown to be almost completely inhibited in cells expressing boMX1. The inhibitory potential of boMX1 was so strong it could only be measured upon the replacement of the low pathogenic H1N1 strain used in the first assays by the hypervirulent H7N7 one. In this case, the protection rate was as high as 108. Typically, the value found for the human counterpart MXA is in the range of 103 – 104 and according to our knowledge, none of the MX proteins investigated so far have never been shown to be so effective against Influenza A. In the wave of these results, the well-known avian H5N1 Influenza A strain has been tested in vitro and in vivo. All the data reinforced the concept of a very high anti-Influenza A activity for BoMX1. A such important antiviral effect appeared as an opportunity to initiate an experimental approach of the largely unknown underlying mechanism(s) of the MX antiviral activity. Our first objective was to identify the “primum movens” of the inhibition mechanism. Therefore, we followed the kinetic of the infection in V103 expressing or not the boMX1 during one single cycle. The evidence of an important activity of the bovine GTPase in the first hours post-infection led us to identify at the RNA level which replication step was the first to be blocked. Following the collected results, we adapted a primer extension method to quantify the genomic viral RNA (vRNA) early entry in the induced and non induced cell cultures. Finally, we tested a first interaction hypothesis between the boMX1 and a potential interacting protein sister. [less ▲]

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See detailLimits imported from economics
Sibony, Anne-Lise ULg

Conference (2009, May 28)

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See detailRegulatory T cells in Wiskott-Aldrich syndrome and after allogeneic transplantation with nonmyeloablative conditioning
Humblet-Baron, Stéphanie ULg

Doctoral thesis (2009)

Etude des Treg dans la physiopathologie du syndrome de Wiskott-Aldrich et étude de la reconstitution des Treg dans les greffes de cellules souches hématopoïétiques après un conditionnement ... [more ▼]

Etude des Treg dans la physiopathologie du syndrome de Wiskott-Aldrich et étude de la reconstitution des Treg dans les greffes de cellules souches hématopoïétiques après un conditionnement nonmyéloablateur. [less ▲]

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See detailQuantum Computers: A Brief Overview
Merciadri, Luca ULg

E-print/Working paper (2009)

A promising technology is the “quantum computers,” and this paper gives a general overview about this subject.

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See detailLa justice réparatrice en milieu carcéral : plasticité d’une fonction et malléabilité d’un concept criminologique
Dubois, Christophe ULg

Doctoral thesis (2009)

Although it is recognized as being inhuman by some people and inefficient by others, prison only seldomly serves as a gathering political objective. The ministerial circular of 4 October 2000, which is ... [more ▼]

Although it is recognized as being inhuman by some people and inefficient by others, prison only seldomly serves as a gathering political objective. The ministerial circular of 4 October 2000, which is implementing « restorative justice » in Belgian prisons, seems however to be an outstanding case in this matter as it includes prison in the political program. The new “restorative” discourse carried out by this circular creates a new role of “restorative justice consultant” and plans to assign one in each prison. The purpose of this book is to describe, analyze and account for the concrete practices through which this political discourse tends to take some social forms. Through an ethnographic work, the new “restorative” practices will be depicted and replaced in a policy and organizational analysis based on four case studies. [less ▲]

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