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See detailPhoto-crosslinkable hydrogel for guided periodontal tissue regeneration
Chichiricco, Pauline Marie ULg; Riva, Raphaël ULg; Thomassin, Jean-Michel ULg et al

Poster (2017, May 04)

Periodontitis is an inflammatory disease resulting from the presence of oral bacteria biofilm in periodontal tissue, which destroys the tooth-supporting attachment apparatus. Untreated inflammation can ... [more ▼]

Periodontitis is an inflammatory disease resulting from the presence of oral bacteria biofilm in periodontal tissue, which destroys the tooth-supporting attachment apparatus. Untreated inflammation can spread to the gum tissue and lead, ultimately, to the loosening of the supporting tooth bone, with the risk that the tooth eventually falls. Guided Tissue Regeneration is a technique based on the application of a barrier membrane designed to prevent colonization of the wound space by epithelial cells from soft tissues. Indeed, these cells, characterized by a faster migration and proliferation rate compared to bone and periodontal ligament cells, could interfere with the regeneration process. In previously work Struillou et al. demonstrated the benefit effect of silated hydroxypropylmethylcellulose (Si HMPC)-based hydrogel can act as an efficient physical barrier in periodontal defect. Typically, this material is able to form a 3D network through the condensation of silanoate groups at physiological pH. However, a decrease of gelation time is necessary to assure the stability in peripheral part of the wound. In this project, we developed an injectable photo-crosslinkable membrane based on methacrylated carboxymethyl chitosan (CMCs) and Si HPMC that can be applied as a viscous solution and cured in situ in presence of a photoinitiator system made of riboflavin and triethanolamine. A visible light lamp (λ 420-480 nm), already used in dentistry, was preferred over a UV lamp. The addition of methacrylated polymer increase the stability of the material and increase the mass loss, in order to improve the bioresorption of the membrane. The chemical grafting of methacrylated carboxymethyl chitosan was characterized by 1H NMR and Infrared Spectroscopy. The gel point of the solution was determined by rheology and remained compatible with a clinical application. Moreover, the biocompatibility of this biomaterials was tested using murine cells using two assay: Neutral Red assay and MTT Cell Proliferation Assay. The in vitro tests validate the chemical synthesis in a biological point of view. The irradiation on cells and the direct contact with hydrogel doesn’t have an impact on cells viability. The capability of this material to act as a physical barrier was also evaluated using human gingival fibroblast. The cells were isolated from human gum explant before being put in contact with the hydrogel. After four days of contact no cells invasion was observed in the hydrogel using confocal microscopy. These preliminary results are quite promising for the development of novel injectable systems for Guided Periodontal Regeneration. In the future work, in vivo assays will be performed in Periodontal defect in a canine model. [less ▲]

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See detailSynthesis of well-defined polyvinylamine-containing copolymers via organometallic-mediated radical polymerization
Stiernet, Pierre ULg; Demarteau, Jérémy ULg; Jérôme, Christine ULg et al

Poster (2017, May 04)

Polyvinylamine (PVAm) is a useful polymer involved in a large range of applications including paper coating, surface engineering, membrane separation, etc. It is commonly produced via free radical ... [more ▼]

Polyvinylamine (PVAm) is a useful polymer involved in a large range of applications including paper coating, surface engineering, membrane separation, etc. It is commonly produced via free radical polymerization of N-vinylformamide (NVF) or N-vinylacetamide (NVA) followed by hydrolysis of the pendent amides of the resulting polymers. Due to the lack of stabilizing group on the double bond of N-vinylamides, the controlled radical polymerization of these monomers remained a challenge for a long time, preventing the preparation of well-defined PVAms. Recently, our group reported the controlled polymerization of NVA via reversible deactivation of the growing radical chains with cobalt complexes. Moreover, the use of well-defined PVAms as efficient carriers for gene transfection was demonstrated. This communication aims at reporting the synthesis of novel well-defined polyvinylamine-based copolymers. First, we explored the organometallic-mediated radical copolymerization of NVA and vinyl acetate. The optimized polymerization conditions and the comonomer reactivity ratios will be presented. Further conversion of the pendent amides and esters moieties into amino and hydroxy groups, respectively, was also considered for the preparation of unprecedented hydrophilic polyvinylamine-based copolymers. [less ▲]

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See detailDSC et XRD à température contrôlée: outils indispensables pour l'étude des corps gras
Danthine, Sabine ULg

Scientific conference (2017, May 03)

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See detailMontenegrin ponds and lakes under threat: multiple stressors caused large-scale amphibian decline
Denoël, Mathieu ULg; Kalezić, Miloš; Džukić, Georg et al

Conference (2017, May 03)

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See detailSpray droplet impaction outcomes for different plant species and spray formulations
Massinon, Mathieu ULg; De Cock, Nicolas ULg; Forster, W. Alison et al

in Crop Protection (2017), 99

A track-sprayer combined with a high-speed camera were used to visualize and identify droplet impaction outcomes for three formulations (water, 0.1% LI 700® (lecithin, a mixture of soya oils, propionic ... [more ▼]

A track-sprayer combined with a high-speed camera were used to visualize and identify droplet impaction outcomes for three formulations (water, 0.1% LI 700® (lecithin, a mixture of soya oils, propionic acid and surfactants) in water and 0.1% Pulse® (non-ionic surfactant, trisiloxane ethoxylate) in water) on four plant species (bean (Vicia faba L.), avocado (Persea americana L.), barnyard grass (Echinochloa crus-galli L. P. Beauv.) and cabbage (Brassica oleracea L.)) selected to represent a wide range of leaf surface characters. Droplet sizes and velocities were measured by image analysis and a multiple hypothesis tracking algorithm. Impaction outcomes were categorized into adhesion, bounce, or shatter. The probability of each outcome was estimated from logistic regression models related to the dimensionless Weber number. This approach is in contrast to various deterministic threshold criteria for droplet bounce or shatter that have been used to model droplet impaction events on leaves. It also provides a simple visual and numerical presentation of the complexity of impaction processes, and the relative influence of leaf surface character versus formulation for droplets with different impaction energies. [less ▲]

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See detailOUFTI-2 educational CubeSat project of University of Liège, Belgium
Guillaume, Thibaut; Rikir, Adrien; De Dijcker, Sébastien ULg et al

Scientific conference (2017, May 03)

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See detailChangements climatiques : les causes et les moyens d’atténuation
Beckers, Yves ULg

Scientific conference (2017, May 03)

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See detailModel-based classification of CPT data and automated lithostratigraphic mapping for high-resolution characterization of a heterogeneous sedimentary aquifer
Rogiers, Bart; Mallants, Dirk; Batelaan, Okke et al

in PLoS ONE (2017), 12(5), 0176656

Cone penetration testing (CPT) is one of the most efficient and versatile methods currently available for geotechnical, lithostratigraphic and hydrogeological site characterization. Currently available ... [more ▼]

Cone penetration testing (CPT) is one of the most efficient and versatile methods currently available for geotechnical, lithostratigraphic and hydrogeological site characterization. Currently available methods for soil behaviour type classification (SBT) of CPT data however have severe limitations, often restricting their application to a local scale. For parameterization of regional groundwater flow or geotechnical models, and delineation of regional hydro- or lithostratigraphy, regional SBT classification would be very useful. This paper investigates the use of model-based clustering for SBT classification, and the influence of different clustering approaches on the properties and spatial distribution of the obtained soil classes. We additionally propose a methodology for automated lithostratigraphic mapping of regionally occurring sedimentary units using SBT classification. The methodology is applied to a large CPT dataset, covering a groundwater basin of ~60 km2 with predominantly unconsolidated sandy sediments in northern Belgium. Results show that the model-based approach is superior in detecting the true lithological classes when compared to more frequently applied unsupervised classification approaches or literature classification diagrams. We demonstrate that automated mapping of lithostratigraphic units using advanced SBT classification techniques can provide a large gain in efficiency, compared to more time-consuming manual approaches and yields at least equally accurate results. [less ▲]

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See detailPolyphenolic profile and biological activities of the leaves and aerial parts of Echinocystis lobata (Michx.) Torr. et A.Gray (Cucurbitaceae)
Ielciu, Irina-Ioana ULg; Vlase, Laurian; Frederich, Michel ULg et al

in Farmacia (2017), 65(2), 179-183

The aim of the present study consisted in the quantification of the polyphenols in leaves and aerial parts of Echinocystis lobata (Michx.) Torr. et A.Gray and testing its biological potential. Analysis of ... [more ▼]

The aim of the present study consisted in the quantification of the polyphenols in leaves and aerial parts of Echinocystis lobata (Michx.) Torr. et A.Gray and testing its biological potential. Analysis of polyphenols was performed by a HPLC-MS method. Antioxidant activity of the extracts was tested by DPPH, CUPRAC, FRAP, TEAC, EPR and SNPAC assays. Cytotoxic activity was assessed on cancerous and healthy cell lines. Anti-plasmodial tests were performed on two strains of Plasmodium falciparum. Ethanolic extracts of E. lobata contain mainly p-coumaric acid, isoquercitrin, rutin, quercitrin and kaempferol. Biological assays showed a significant antioxidant effect and no cytotoxic and anti-plasmodial activity. These results offer a new perspective on E. lobata, proving it as an important source of antioxidant compounds. [less ▲]

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See detailLe renseignement dans le champ d'expertise de la science politique
Leroy, Patrick ULg

Speech/Talk (2017)

L’objectif de notre contribution est de promouvoir l’étude du renseignement comme domaine d’expertise de la science politique. En observant les domaines traditionnels d’études de la science politique en ... [more ▼]

L’objectif de notre contribution est de promouvoir l’étude du renseignement comme domaine d’expertise de la science politique. En observant les domaines traditionnels d’études de la science politique en effet, on constate que le renseignement, dans ses diverses déclinaisons, s’inscrit transversalement dans nombre d’entre eux (relations internationales, diplomatie, administrations publiques, politiques publiques belges et européennes, gouvernance, sécurité/paix/conflits), bien qu’il conserve sa multidisciplinarité (droit, histoire, criminologie, science de gestion, …). [less ▲]

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See detailOPTIBRI Opening and Project Overview
Habraken, Anne ULg; Duchene, Laurent ULg; Bouffioux, Chantal ULg et al

Conference (2017, May 03)

presentation of genesis of the project, his goal and objectives, the partnership, the task flowchart and main achievements

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See detailPenser l’anticipation par le discours social. Variations sur le radium
Stienon, Valérie ULg

Conference (2017, May 03)

Une véritable fureur du radium s’empare du premier tiers du XXe siècle, sur une période allant de la découverte des rayons X par Röntgen en 1895, de la radioactivité par Becquerel en 1896 puis du radium ... [more ▼]

Une véritable fureur du radium s’empare du premier tiers du XXe siècle, sur une période allant de la découverte des rayons X par Röntgen en 1895, de la radioactivité par Becquerel en 1896 puis du radium par le couple Curie en 1898, jusqu’à la mort de Marie Curie en 1934. Le radium constitue un cas intéressant pour interroger les possibles de la science, l’extension de l’imaginaire social par ses applications au quotidien et ses modalités de mise en récit entre réalité, croyance et fiction. À travers un large corpus d'articles de presse (articles scientifiques, romans-feuilletons, publicités, petites annonces, blagues illustrées) et de romans (aventure, fantastique, espionnage), la communication propose une approche contextuelle et médiatique du récit d'anticipation. La réflexion doit permettre de réévaluer des cadres de réception de l'anticipation souvent limités à l’alternative entre prophétisme du texte supposé visionnaire et obsolescence de la thématique non advenue ou passée de mode. [less ▲]

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See detailApproche par compétences - Impact sur les pratiques pédagogiques et l'offre de formation
Georges, François ULg

Scientific conference (2017, May 02)

Intervention réalisée à l’occasion de la présentation des démarches menées dans le cadre du projet Tempus « Apprentissage à Distance et innovation pédagogique -ADIP ». Dans cette présentation sont passés ... [more ▼]

Intervention réalisée à l’occasion de la présentation des démarches menées dans le cadre du projet Tempus « Apprentissage à Distance et innovation pédagogique -ADIP ». Dans cette présentation sont passés en revue les différentes acceptions du terme compétence, les éléments à prendre en considération pour construire un référentiel, ses traductions possibles dans un programme sur base de six principes, les changements qu’il entraîne au niveau des cours et les conditions de son déploiement. La majorité des illustrations est extraite des expériences menées dans le cadre du projet ADIP au Liban et en Égypte. [less ▲]

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See detailAn Improved On-line Contingency Screening for Power System Transient Stability Assessment
Weckesser, Johannes ULg; Jóhannsson, Hjörtur; Glavic, Mevludin ULg et al

in Electric Power Components & Systems (2017)

This paper presents a contingency screening method and a framework for its on-line implementation. The proposed method carries out contingency screening and on-line stability assessment with respect to ... [more ▼]

This paper presents a contingency screening method and a framework for its on-line implementation. The proposed method carries out contingency screening and on-line stability assessment with respect to first-swing transient stability. For that purpose, it utilizes the single machine equivalent method and aims at improving the prior developed contingency screening approaches. In order to determine vulnerability of the system with respect to a particular contingency, only one time-domain simulation needs to be performed. An early stop criteria is proposed so that in a majority of the cases the simulation can be terminated after a few hundred milliseconds of simulated system response. The method’s outcome is an assessment of the system’s stability and a classification of each considered contingency. The contingencies are categorized by exploiting parameters of an equivalent one machine infinite bus system. A novel island detection approach, appropriate for an on-line application since it utilizes efficient algorithms from graph theory and enables stability assessment of individual islands, is also introduced. The New England and New York system as well as the large-scale model of the Continental-European interconnected system are used to test the proposed method with respect to assessment accuracy and computation time. [less ▲]

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See detailSAFIR: a software for modeling structures in fire
Franssen, Jean-Marc ULg; Gernay, Thomas ULg

Poster (2017, May 02)

SAFIR is a computer program developed at University of Liege to model the behavior of building structures subjected to fire.

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See detailHybrid Fire Testing: A new approach for fire labs
Sauca, Ana ULg; Gernay, Thomas ULg; Mergny, Elke ULg et al

Poster (2017, May 02)

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See detailWal-e-Cities
Schelings, Clémentine ULg; Reiter, Sigrid ULg; Teller, Jacques ULg et al

Poster (2017, May 02)

L’objectif du portefeuille FEDER Wal-e-Cities est le développement de villes intelligentes («Smart Cities») au sein d’un territoire wallon interconnecté. La technologie, vue ici comme un outil au service ... [more ▼]

L’objectif du portefeuille FEDER Wal-e-Cities est le développement de villes intelligentes («Smart Cities») au sein d’un territoire wallon interconnecté. La technologie, vue ici comme un outil au service de la Smart Région Wallonne et de ses citoyens, permettra de répondre à cinq défis principaux identifiés: connectivité, mobilité, énergie et environnement, gouvernance et enfin bien-être en environnement urbain. Les partenaires de ce portefeuille (Universités et Centres de Recherche), et parmi eux l’UR Urban & Environmental Engineering de l'Ulg, oeuvreront au déploiement de solutions dédiées en regard des besoins spécifiques (géographiques, démographiques, socio-économiques et culturels) de chaque ville pilote partenaire. [less ▲]

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See detailSurrogate Generation and Evaluation for Biodiesel and Its Mixtures with Fossil Diesel
Reiter, Anton M.; Schubert, Nikolai; Pfennig, Andreas ULg et al

in Energy & Fuels (2017), 31

In this paper a precedently developed surrogate optimization algorithm for fossil fuels, which originally allowed simultaneous fitting of the true boiling point (TBP) curve, the liquid density at 15 °C ... [more ▼]

In this paper a precedently developed surrogate optimization algorithm for fossil fuels, which originally allowed simultaneous fitting of the true boiling point (TBP) curve, the liquid density at 15 °C, and the cetane number, is refined toward its application to biodiesel and its mixtures with fossil diesel. For this purpose, the algorithm is extended (1) to also include fitting of the kinematic viscosity at 40 °C and (2) to account for peculiarities of biodiesel concerning its narrow boiling range and compensation of systematic errors of measured boiling curves. To illustrate these improvements, first, the algorithm is applied to property estimation and surrogate optimization of three different biodiesel fuels, for which surrogates consisting of one to three components are proposed. Second, a surrogate for a commercial European fossil diesel is calculated and produced in lab-scale. Finally, the algorithm is used for surrogate optimization and property estimation of mixtures of biodiesel and fossil diesel, considering fractions of biodiesel of 7% and 20% per volume. It is shown that the improved algorithm is capable of reliably optimizing surrogates for fuels containing both biogenic and fossil components. [less ▲]

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