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See detailMulti-scale stochastic study of the grain orientation and roughness effects on polycrystalline thin structures
Lucas, Vincent ULg; Wu, Ling ULg; Golinval, Jean-Claude ULg et al

Conference (2016, June 09)

When studying micro-electro-mechanical systems (MEMS) made of poly-crystalline materials, as the size of the device is only one or two orders of magnitude higher than the size of the the grains, the ... [more ▼]

When studying micro-electro-mechanical systems (MEMS) made of poly-crystalline materials, as the size of the device is only one or two orders of magnitude higher than the size of the the grains, the structural properties exhibit a scatter at the macro-scale due to the existing randomness in the grain size, grain orientation, surface roughness... In order to predict the probabilistic behavior at the structural scale, the authors have recently developed a stochastic 3-scale approach [1]. In this method, stochastic volume elements (SVEs) [2] are defined by considering random grain orientations in a tessellation. For each SVE realization, a meso-scopic apparent material tensor can be obtained using the computational homogenization theory. The extracted meso-scopic apparent material tensors can then be used to defined a spatially correlated meso-scale random field, which is in turn used as input for stochastic finite element simulations. In this work we intend to study the effect of different material-related uncertainty sources on the structural behavior of vibrating micro-devices manufactured using low pressure chemical vapor deposition. First, the effect of preferred grain orientation on vibrating micro-structures is assessed. To this end, SVEs are generated so that their grain orientation distributions follow XRD measurements. Second, the effect of the roughness of the vibrating micro-structures is studied. Toward this end, SVEs, whose rough surface statistical properties follow AFM measurements, are generated. A second-order computational homogenization [3] applied on the different SVE realizations allows defining a meso-scale random field of the in-plane and out-of-plane meso-scale shell properties. Stochastic shell finite elements can then be applied to predict the MEMS probabilistic behavior. [1] V. Lucas, et al., Comp. Meth. in Appl. Mech. and Eng., 294, 141-167, 2015 [2] M. Ostoja-Starzewski, X.Wang, Comp. Meth. in Appl. Mech. and Eng., 168, 35–49, 1999 [3] E.W.C. Coenen, V. Kouznetsova, M.G.D. Geers. Int. J. for Numer. Meth. in Eng., 83, 1180–1205, 2010. [less ▲]

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See detailMALDI-imaging guided microproteomics workflow for biomarker discovery of intra-tumor heterogeneity
Alberts, Deborah ULg; Longuespée, Rémi ULg; Smargiasso, Nicolas ULg et al

Poster (2016, June 09)

Introduction A single tumoral tissue can bear phenotypically different cell populations. This phenomenon called intra-tumor heterogeneity can lead to differential behaviors regarding metastasis seeding ... [more ▼]

Introduction A single tumoral tissue can bear phenotypically different cell populations. This phenomenon called intra-tumor heterogeneity can lead to differential behaviors regarding metastasis seeding and therapy resistance [Zardavas et al., Nature Rev. Clin. Onc. 2015]. MALDI imaging has proven its efficiency for revealing hidden molecular features offering an insight into distinct cellular regions based on their molecular content. Further, proteomics applied to these regions could allow depicting the molecular context associated to particular cells groups and enable the collection of qualitative, quantitative and spatial information for each protein. Methods Breast cancer Formalin Fixed and Paraffin Embedded tissues, from patients whose outcome had been recorded over a period of 10 years, were provided by the department of Pathology of University of Liège. After Citric Acid Antigen Retrieval and trypsin digestion, images were obtained by MALDI-TOF/TOF-MS (Bruker, Germany). From the obtained datasets, segmentation and analytical data analysis were applied using SCiLS (Bruker, Germany) and the cloud software Multimaging (ImaBiotech, France). Small tissue areas were obtained by laser microdissection (LEICA LMD 700, Germany), upon which a combination of chemical processes was applied to ensure optimal protein antigen retrieval, extraction and digestion. Finally, the tissue pieces obtained were analyzed by LC-MS/MS using UPLC Waters Nanoacquity and Thermo Q-Exactive instruments. Preliminary data Based on mathematical calculations for the MALDI imaging datasets of the breast cancer FFPE tissues, Regions Of Interest (ROIs) were detected in a single tumor, revealing intra-tumoral heterogeneity, which can be correlated to the level of aggressiveness of the affliction and to the final prognosis of the patient. We aimed to compare the proteomic profiles of each of the small ROIs. Until today, proteomics applied to tissues composed by a restricted number of cells is quite tedious due to possible tissue losses during their handling. Recently, Longuespée [Longuespée et al., Methods 2015] published a method in order to retrieve the identification of 1400 proteins from microdissected tissue pieces containing only 2700 cells. This whole procedure allowed us to identify a panel of protein that characterizes tissue heterogeneity within a single tumor. This proves the applicability of the combination of MALDI imaging for the discovery of intra-tumoral heterogeneity without a priori, on a mathematical basis, and classical proteomics applied on laser-microdissected tissue samples of very restricted areas. This method will now be applied to several MALDI datasets in order to retrieve commune ROIs and to associate their presence with the information of each patient, such as their prognosis. Those ROIs will then be microdissected and subjected to microproteomic methods that will allow us to retrieve the extensive molecular context associated to bad patient prognosis and/or therapy resistance. The possibility to identify protein/peptide markers will have the power to predict the outcome of the breast cancer patient at the beginning of their treatment, and thus, improve the clinical care for the benefit of the patients. Novel aspect The workflow combines the unique advantages of MALDI imaging for de novo molecular features characterization and LMD-based microproteomics. [less ▲]

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See detailTime and Space. An Introduction (with a special focus on Linguistics and Semantics)
Winand, Jean ULg; Chantrain, Gaëlle

Conference (2016, June 09)

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See detailFingerprinting and validation of a LC-DAD method for the analysis of biflavanones in Garcinia kola-based antimalarial improved traditional medicines
Tshisekedi Tshibangu, Pascal ULg; Mutwale Kapepula, Paulin ULg; Kabongo Kapinga, Marie Josée et al

in Journal of Pharmaceutical and Biomedical Analysis (2016), 128(2016), 382-390

African populations use traditional medicines in their initial attempt to treat a range of diseases. Nevertheless, accurate knowledge of the composition of these drugs remains a challenge in terms of ... [more ▼]

African populations use traditional medicines in their initial attempt to treat a range of diseases. Nevertheless, accurate knowledge of the composition of these drugs remains a challenge in terms of ensuring the health of population and in order to advance towards improved traditional medicines (ITMs). In this paper chromatographic methods were developed for qualitative and quantitative analyses of a per os antimalarial ITM containing Garcinia kola. The identified analytical markers were used to establish TLC and HPLC fingerprints. G. kola seeds were analysed by HPLC to confirm the identity of the extract used by the Congolese manufacturer in the ITM. The main compounds (GB1, GB2, GB-1a and Kolaflavanone) were isolated by preparative TLC and identified by UPLC–MS and NMR. For the quantification of the major compound GB1, a simple and rapid experimental design was applied to develop an LC method, and then its validation was demonstrated using the total error strategy with the accuracy profile as a decision tool. The accurate results were observed within 0.14–0.45 mg/mL range of GB1 expressed as naringenin. The extracts used in several batches of the analysed oral solutions contained GB1 (expressed as naringenin) within 2.04–2.43%. Both the fingerprints and the validated LC-DAD were found suitable for the quality control of G. kolabased raw material and finished products, respectively. [less ▲]

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See detailNouvelles normes sylvicoles pour les peuplements purs équiennes d'épicéa et de douglas
Perin, Jérôme ULg; Hebert, Jacques ULg; Lejeune, Philippe ULg et al

E-print/Working paper (2016)

Ces documents rassemblent les tables de production (version 2016) représentant les nouvelles normes sylvicoles recommandées pour les peuplements purs équiennes d'épicéa commun et de douglas. Un ensemble ... [more ▼]

Ces documents rassemblent les tables de production (version 2016) représentant les nouvelles normes sylvicoles recommandées pour les peuplements purs équiennes d'épicéa commun et de douglas. Un ensemble de 10 tables de production est présentée pour chaque essence, associant deux densités de plantation (2.5 x 2 m et 2 x 2 m) et 5 classes de productivité (0 à IV). [less ▲]

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See detailStimulation économique : promenade dans le champ des possibles pour l'Etat belge
Behrendt, Christian ULg

Conference given outside the academic context (2016)

Conférence prononcée à la Chambre de commerce et d'industrie du Luxembourg belge, Libramont, 9 juin 2016

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See detailFunctional analysis of PEBP genes in root chicory (Cichorium intybus)
Saintmard, Nicolas ULg; Tocquin, Pierre ULg; Périlleux, Claire ULg

Poster (2016, June 09)

Manipulating plant architecture is key to increase crop yield. In this perspective, basic knowledge on the molecular mechanisms regulating plant growth and development will be fundamental for the future ... [more ▼]

Manipulating plant architecture is key to increase crop yield. In this perspective, basic knowledge on the molecular mechanisms regulating plant growth and development will be fundamental for the future of agriculture. Recent progress indicates that a family of plant genes, homologous to POSPHADITYLETHANOLAMINE-BINDING PROTEINS (PEBP) in other eukaryotes, plays critical roles in controlling shoot development traits such as branching, flowering, bud dormancy or tuberization. Very little is known however on the functions of these genes in root development. The current research will attempt to answer this question in the case of Cichorium intybus, a biannual plant cultivated for the extraction of inulin (a polymer of fructose) from its root. Functional analyses will include expression kinetics, complementation tests in Arabidopsis mutants and creation of PEBP- overexpressing or silencing chicory plants. The preliminary steps of the project are the identification of PEBP genes in chicory by in silico analyses, the determination of the time of the storage root initiation and the establishment of a regeneration protocol for the genetic transformation. [less ▲]

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See detailPromote physical activity and reduce ageism across generations: effects of an intergenerational program
Mouton, Alexandre ULg; Heldenbergh, Corentin ULg; Flamion, Allison ULg et al

Conference (2016, June 09)

Introduction From early to later age populations, regular physical activity (PA) could be considered as a key behaviour to struggle against the major health, mental, social and economic issues of the 21st ... [more ▼]

Introduction From early to later age populations, regular physical activity (PA) could be considered as a key behaviour to struggle against the major health, mental, social and economic issues of the 21st century (Rippe & Angelopoulos, 2010). Among PA interventions, international scientific statements recommend an emerging approach targeting specific intergenerational dyads, such as grandparent-grandchild pairs (Marcus et al., 2006). Besides, Ory and colleagues (2003) underlined that intergenerational interactions could also combat aging stereotypes across generations. Accordingly, the aim of this study was to examine the effects of an intergenerational PA program on PA behaviours and aging stereotypes of grandparent-grandchild pairs. Methods Intergenerational grandparent-grandchild pairs were recruited in two Belgian municipalities. Those two groups took part in a three-month intergenerational intervention, adapted from a previous intervention (Mouton, Renier & Cloes, 2015) and including one weekly session of PA. Assessments were performed before (T0), during (process analysis) and after the intervention (T1). Grandparents PA was assessed with the QAPPA and the SF-36 questionnaires and with a battery of physical fitness test (SFT). The UCLA loneliness scale was also administrated to seniors. Grandchildren PA was evaluated with a seven items Likert scale. Relationship quality and ageism stereotypes between generations were assessed using a combination of existing validated instruments. Results and conclusions The intergenerational groups were composed of 14 dyads of grandparent (65±3.2 years)-grandchild (8.8±2.3 years) in one municipality and 6 dyads of grandparent (64±4.5 years)-grandchild (7.7±1.3 years) in the second. By its combination of physical and psychosocial objectives, the results of this study are expected to provide a significant and original contribution to the research field. If intergenerational PA has the potential to reduce ageism, it could pave the way to interdisciplinary interventions among physical education professionals. [less ▲]

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See detailPour une architecture durable en République Démocratique du Congo. Animation d'ateliers.
Frankignoulle, Pierre ULg

Scientific conference (2016, June 09)

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See detailThe Liège Game Lab: presentation of a young research center on videogames
Dozo, Björn-Olav ULg; Barnabé, Fanny ULg; Delbouille, Julie ULg et al

Conference (2016, June 09)

The main goals of the paper are, first, to present the Liège Game Lab, the different studies carried out in Liège on videogames and their specificities and, secondly, question our own position in the ... [more ▼]

The main goals of the paper are, first, to present the Liège Game Lab, the different studies carried out in Liège on videogames and their specificities and, secondly, question our own position in the research field. To do so, we will situate ourselves in relation to the main paradigms of game studies dominated in France by social sciences and in the world by English-speakers, with a particular attention to the domination’s concerns of a peripheral position. This paper will focus on presentation and discussion of the videogames’ study in a midsized French speaking University. The aim is, first and foremost, to question the domination’s issues related to a triple peripheral position: geographic, methodological and linguistic. - The University of Liège is indeed peripheral in Belgium, in comparison to the centrality, geographically speaking, of the Universities of Brussels and Leuven. - The main group working on videogames, in French speaking Belgium, is the LabJMV (the “Games and Virtual Worlds” Laboratory), where the anthropological and sociological perspectives are dominant, while in Liège we developed more a communicative and literary outlook. - The OMNSH (the main association about game studies in France), which could be our “natural” link to the field because of the sharing language, is also dominated by social sciences and separated by a political frontier which could be seen as a boundary. - The DIGRA (the Digital Games Research Association), at the opposite, is geographically close to us (given that they are present as a chapter in Flanders), but disconnected owing to the difference of language (they publish mainly in English, we publish mainly in French). Despite of this peripheral position and making of it a strategic observatory of the tendencies of game studies, an original research hub emerged in Liège for two years. We chose to work on objects and/or with methodological perspectives which diverge of mainstream game studies: amateur game making, videogame press, Belgian players’ uses and poetical perspective on gaming practices. Various contingencies brought together at the University of Liège several researchers working more or less directly on videogames: students’ demands to write master’s thesis on videogames, the rise of grants from funding agencies like FNRS to study this medium and the development of Digital Humanities in the University of Liège. It is time, now, to question ourselves about the situation of the game studies in the University of Liège, but also the place of this University in the international field of this discipline. In first approximation, we can postulate that this gathering of researchers generated a shared research process, whose specificities stem particularly from the triple peripheral position (geographic, methodological and linguistic) of the University of Liège in the game studies field – as explained earlier. However, we would like to discuss this hypothesis not only on our own,but publicly, in the context of an international conference. Consequently, with this paper, we aim to present our group questioning our shared position and, at the same time, to expose a comparison of our five perspectives on videogames in order to understand in what ways they match each other and in what ways they create fruitful opposition. Björn-Olav Dozo and Boris Krywicky are interested in French speaking videogame press with book history’s methods. Pierre-Yves Hurel examines amateur game design with sociological tools (the dominant methodology in French speaking game studies), but these are serving communication and political investigations. Fanny Barnabé studies the same kind of objects (players’ creative practices of “misappropriation”), but through a formal and poetic approach (she analyzes the works so produced and not the players’ activities). Julie Delbouille, at the opposite, adopted a sociological and quantitative methodology, but investigated a restricted category of gaming practices: the French speaking Belgian players. [less ▲]

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See detailTwo novel ways to impose free-slip boundary conditions in fluid-structure interaction problems using the Particle Finite Element Method
Cerquaglia, Marco Lucio ULg; Deliège, Geoffrey ULg; Boman, Romain ULg et al

Conference (2016, June 09)

As well known, the imposition of boundary conditions is, in many cases, the trickiest part in solving differential problems, both from a physical and numerical standpoint. This work focuses on the way ... [more ▼]

As well known, the imposition of boundary conditions is, in many cases, the trickiest part in solving differential problems, both from a physical and numerical standpoint. This work focuses on the way boundary conditions are accounted for in the solution of fluid-structure interaction problems using the Particle Finite Element Method (PFEM). In particular, the PFEM traditionally employs no-slip conditions on the fluid-solid interfaces. Our aim is twofold. On the one hand, we demonstrate that, in the framework of the PFEM, the no-slip hypothesis is too strong in some cases, leading to erroneous physical results, and that a free-slip condition is to be preferred instead; we therefore propose two novel ways to impose free-slip conditions, devoting special attention to generality, simplicity and robustness. On the other hand, we show how the use of free-slip boundary conditions can also be beneficial with regards to two major problems arising from the remeshing procedure employed by the PFEM: the violation of the mass conservation principle and the introduction of spurious pressure oscillations. [less ▲]

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See detailComplete coding sequence of one H9 and three H7 low pathogenic influenza viruses circulating in wild birds in Belgium, 2009-2012
Van Borm, Steven; Rosseel, Toon; Marché, Sylvie et al

in Genome Announcements (2016), 4(3),

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See detailStability in Hybrid Fire Testing
Sauca, Ana ULg; Gernay, Thomas ULg; Robert, Fabienne et al

in Garlock, Maria; Kodur, Venkatesh (Eds.) Structures in Fire (Proceedings of the Ninth International Conference) (2016, June 09)

Hybrid testing is an appealing technique to observe the behavior of an element in an experimental test while taking into account the interaction with the rest of the structure which is modelled ... [more ▼]

Hybrid testing is an appealing technique to observe the behavior of an element in an experimental test while taking into account the interaction with the rest of the structure which is modelled numerically. Being widely used in the seismic field, this technique has been recently proposed in the fire field. The purpose of this paper is to demonstrate that the loading control process may be unstable during the hybrid testing when using the methodology applied in former tests presented in the literature. The stability in the latter method depends on the stiffness ratio between the two substructures. For the purpose of discussion, a one degree-of-freedom elastic system is studied. To overcome the stability issues, a new method is presented, independent on the stiffness ratio. Finally, the hybrid testing of a 2D beam being part of a moment resisting frame is analyzed in a virtual environment (both parts being modeled numerically) using the “first generation method” and the new proposed method. [less ▲]

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See detailNégociations et positions des intermédiaires sur le marché du travail non qualifié : une introduction
Orianne, Jean-François ULg

Conference (2016, June 09)

Comment le travail non qualifié fait-il l’objet d’échanges ? Comment s’effectuent les rencontres et les évaluations sur ce marché ? En s’intéressant aux intermédiaires du MT, l’objectif est de rendre ... [more ▼]

Comment le travail non qualifié fait-il l’objet d’échanges ? Comment s’effectuent les rencontres et les évaluations sur ce marché ? En s’intéressant aux intermédiaires du MT, l’objectif est de rendre compte du travail d’organisation, de médiation, de mise en valeur et d’évaluation effectué sur ce marché. [less ▲]

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See detailDescription of a laboratory's carrot
Vangeebergen, Thomas ULg

Scientific conference (2016, June 08)

Participation to a workshop on specific issues in ethnography: how to describe accurately and efficiently the objects present on the fieldwork? Each participant brings a short text with a depiction of a ... [more ▼]

Participation to a workshop on specific issues in ethnography: how to describe accurately and efficiently the objects present on the fieldwork? Each participant brings a short text with a depiction of a particular object (tool, organization, vehicle, apparatus, document, etc.), and try to show how it feeds the thin understanding of the situation, and allows a certain theoretical analysis. All participants comment the other texts and propose solutions to improve the quality of texts [less ▲]

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See detailBrexit et défense européenne. Décryptage
Dumoulin, André ULg

in e-Note (2016), 20

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See detailImpurity scattering effects on the superconducting properties and the tetragonal-to-orthorhombic phase transition in FeSe
Abdel-Hafiez, Mahmoud; Pu, Y. J.; Brisbois, Jérémy ULg et al

in Physical Review B (2016), 93

A comprehensive study of the doping dependence of the phase diagram of FeSe-based superconductors is still required due to the lack of a clean and systematic means of doping control. Here, we report on ... [more ▼]

A comprehensive study of the doping dependence of the phase diagram of FeSe-based superconductors is still required due to the lack of a clean and systematic means of doping control. Here, we report on the magneto-optical imaging, thermodynamic and transport properties, as well as in situ angle-resolved photoemission spectroscopy (ARPES) studies, on the impurity scattering in stoichiometric FeSe single crystals. Co doping at the Fe site is found to decrease the superconducting transition temperature. The upper critical field and specific heat all indicate a possible multiband superconductivity with strong coupling in the Co-doped system. A remarkable feature in FeSe is that its temperature dependent resistivity exhibits a wide hump at high temperatures, a signature of a crossover from a semiconductinglike behavior to metallic behavior. A structural tetragonal-to-orthorhombic phase transition Ts (a consequence of the electronic nematicity) is suppressed by either physical or chemical pressures. Due to the reconstruction of the Fermi surface at Ts, specific heat anomalies at Ts present ΔCp/Ts≈γn, the Sommerfield coefficient at low temperature. This reflects additional electronic instability in the FeSe(1−x)Sx system. ARPES data between 180 and 282 K indicates the existence of a chemical potential shift with increasing thermal excitations, resulting in a change of the Fermi-surface topology and exhibiting a semimetal behavior. We found that the temperature-induced Lifshitz transition is much higher than the temperature for the nematic order. [less ▲]

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See detailThe MAR model performances over Belgium
Wyard, Coraline ULg; Fettweis, Xavier ULg

Conference (2016, June 08)

This presentation deals with the set-up of the regional climate model MAR over Belgium. It also presents the performances of MAR to simulate the present-day climate following three reanalysis used as ... [more ▼]

This presentation deals with the set-up of the regional climate model MAR over Belgium. It also presents the performances of MAR to simulate the present-day climate following three reanalysis used as forcing of the model (ERA-Interim, ERA-20C and NCEP/NCAR-v1). [less ▲]

Detailed reference viewed: 35 (2 ULg)