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See detailExperimental and computational micro–mechanical investigations of compressive properties of polypropylene/multi–walled carbon nanotubes nanocomposite foams
Wan, Fangyi; Tran, Minh Phuong; Leblanc, Christophe ULg et al

in Mechanics of Materials (2015), 91(Part 1), 95-118

The compressive behavior of nanocomposite foams is studied by both experimental and computational micro-mechanics approaches with the aim of providing an efficient computational model for this kind of ... [more ▼]

The compressive behavior of nanocomposite foams is studied by both experimental and computational micro-mechanics approaches with the aim of providing an efficient computational model for this kind of material. The nanocomposites based on polypropylene (PP) and different contents of multi-walled carbon nanotubes (CNTs) are prepared by melt mixing method. The nanocomposite samples are foamed using super-critical carbon dioxide (ScCO2) as blowing agent at different soaking temperatures. The influence of this foaming parameter on the morphological characteristics of the foam micro-structure is discussed. Differential Scanning Calorimetry (DSC) measurements are used to quantify the crystallinity degree of both nanocomposites and foams showing that the crystallinity degree is reduced after the foaming process. This modification leads to mechanical properties of the foam cell walls that are different from the raw nanocomposite PP/CNTs material. Three--point bending tests are performed on the latter to measure the flexural modulus in terms of the crystallinity degree. Uniaxial compression tests are then performed on the foamed samples under quasi-static conditions in order to extract the macro-scale compressive response. Next, a two-level multi-scale approach is developed to model the behavior of the foamed nanocomposite material. On the one hand, the micro-mechanical properties of nanocomposite PP/CNTs cell walls are evaluated from a theoretical homogenization model accounting for the micro-structure of the semi-crystalline PP, for the degree of crystallinity, and for the CNT volume fraction. The applicability of this theoretical model is demonstrated via the comparison with experimental data from the described experimental measurements and from literature. On the other hand, the macroscopic behavior of the foamed material is evaluated using a computational micro-mechanics model using tetrakaidecahedron unit cells and periodic boundary conditions to estimate the homogenized properties. The unit cell is combined with several geometrical imperfections in order to capture the elastic collapse of the foamed material. The numerical results are compared to the experimental measurements and it is shown that the proposed unit cell computational micro-mechanics model can be used to estimate the homogenized behavior, including the linear and plateau regimes, of nanocomposite foams. [less ▲]

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See detailTribulations d’une vieille dame : De la « loi relative aux anormaux et délinquants d’habitude » à la « loi relative à l’internement des personnes atteintes d'un trouble mental »
Garcet, Serge ULg

in Revue Médicale de Liège (2015), 70e année

Le système belge de prise en charge des délinquants atteints de troubles mentaux est organisé selon un principe de défense sociale. Il se caractérise par une double attention pour, d’une part, la ... [more ▼]

Le système belge de prise en charge des délinquants atteints de troubles mentaux est organisé selon un principe de défense sociale. Il se caractérise par une double attention pour, d’une part, la protection de la société par une neutralisation du risque et, d’autre part, la nécessité de soins à prodiguer à la personne internée. L’évolution du cadre juridique de la loi de 1930 relative aux anormaux et délinquants d’habitude à la loi relative à l’internement des personnes atteintes d'un trouble mental de 2014 rend compte des vicissitudes nées du tiraillement entre ces deux piliers sécuritaire et thérapeutique. Dans ce difficile rapport de forces, bien que publiée mais pas encore d’application, la version de 2014 de la loi constitue à bien des égards une évolution positive dans la prise en compte des personnes internées et de leurs besoins. [less ▲]

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See detailIs the O2(a1Δg) Venus nightglow emission controlled by solar activity ?
Soret, Lauriane ULg; Gérard, Jean-Claude ULg

in Icarus (2015), 262

Several past studies showed that the O2(a1Δg) Venus nightglow emission at 1.27 μm is highly variable on a timescale of hours. We examine whether the intensity of this emission shows a more global trend ... [more ▼]

Several past studies showed that the O2(a1Δg) Venus nightglow emission at 1.27 μm is highly variable on a timescale of hours. We examine whether the intensity of this emission shows a more global trend linked to solar activity. [less ▲]

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See detailNIK promotes tissue destruction independently of the alternative NF-kappaB pathway through TNFR1/RIP1-induced apoptosis.
Boutaffala, L.; Bertrand, M. J. M.; Remouchamps, Caroline ULg et al

in Cell death and differentiation (2015)

NF-kappaB-inducing kinase (NIK) is well-known for its role in promoting p100/NF-kappaB2 processing into p52, a process defined as the alternative, or non-canonical, NF-kappaB pathway. Here we reveal an ... [more ▼]

NF-kappaB-inducing kinase (NIK) is well-known for its role in promoting p100/NF-kappaB2 processing into p52, a process defined as the alternative, or non-canonical, NF-kappaB pathway. Here we reveal an unexpected new role of NIK in TNFR1-mediated RIP1-dependent apoptosis, a consequence of TNFR1 activation observed in c-IAP1/2-depleted conditions. We show that NIK stabilization, obtained by activation of the non-death TNFRs Fn14 or LTbetaR, is required for TNFalpha-mediated apoptosis. These apoptotic stimuli trigger the depletion of c-IAP1/2, the phosphorylation of RIP1 and the RIP1 kinase-dependent assembly of the RIP1/FADD/caspase-8 complex. In the absence of NIK, the phosphorylation of RIP1 and the formation of RIP1/FADD/caspase-8 complex are compromised while c-IAP1/2 depletion is unaffected. In vitro kinase assays revealed that recombinant RIP1 is a bona fide substrate of NIK. In vivo, we demonstrated the requirement of NIK pro-death function, but not the processing of its substrate p100 into p52, in a mouse model of TNFR1/LTbetaR-induced thymus involution. In addition, we also highlight a role for NIK in hepatocyte apoptosis in a mouse model of virus-induced TNFR1/RIP1-dependent liver damage. We conclude that NIK not only contributes to lymphoid organogenesis, inflammation and cell survival but also to TNFR1/RIP1-dependent cell death independently of the alternative NF-kappaB pathway.Cell Death and Differentiation advance online publication, 5 June 2015; doi:10.1038/cdd.2015.69. [less ▲]

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See detailHow to Discount Deep Reinforcement Learning: Towards New Dynamic Strategies
François-Lavet, Vincent ULg; Fonteneau, Raphaël ULg; Ernst, Damien ULg

in NIPS 2015 Workshop on Deep Reinforcement Learning (2015, December)

Using deep neural nets as function approximator for reinforcement learning tasks have recently been shown to be very powerful for solving problems approaching real-world complexity. Using these results as ... [more ▼]

Using deep neural nets as function approximator for reinforcement learning tasks have recently been shown to be very powerful for solving problems approaching real-world complexity. Using these results as a benchmark, we discuss the role that the discount factor may play in the quality of the learning process of a deep Q-network (DQN). When the discount factor progressively increases up to its final value, we empirically show that it is possible to significantly reduce the number of learning steps. When used in conjunction with a varying learning rate, we empirically show that it outperforms original DQN on several experiments. We relate this phenomenon with the instabilities of neural networks when they are used in an approximate Dynamic Programming setting. We also describe the possibility to fall within a local optimum during the learning process, thus connecting our discussion with the exploration/exploitation dilemma. [less ▲]

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See detailAccompagner l'implantation de l'approche par compétences en histoire : avec quels moyens d'enseignement ?
Jadoulle, Jean-Louis ULg

in Didactica historica. Revue suisse pour l'enseignement de l'histoire (2015), 1

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See detailEFHC1/Myoclonin-1 modulates the post-translational modification of microtubules
Medard, Laurie ULg; Godin, Juliette; Coumans, Bernard ULg et al

Poster (2015, December)

Rationale: Juvenile myoclonic epilepsies (JME) are one of the most common forms of genetic generalized epilepsy. Genetic studies have shown that heterozygous mutations in EFHC1/Myoclonin1 are responsible ... [more ▼]

Rationale: Juvenile myoclonic epilepsies (JME) are one of the most common forms of genetic generalized epilepsy. Genetic studies have shown that heterozygous mutations in EFHC1/Myoclonin1 are responsible for 3-22% of JME cases worldwide. The Myoclonin1 protein contains three DM10 domains of unknown function and an EF-hand domain. We have previously demonstrated that Myoclonin1 is a microtubule-associated protein involved in cell division and radial migration during neocortex development. In cells, this protein co-localized with specific structures rich in microtubules (MTs) such as the centrosome, the poles of the mitotic spindle or the motile cilia but not with cytoplasmic MTs. This suggests post-translational modifications (PTM) of MTs may be important for the interaction between Myoclonin1 and MTs Methods: We co-expressed the different enzymes catalyzing PTM of MTs with Myoclonin1 in U2OS cell line, and then performed immunocytochemistry and western blot analysis. We next performed pulldown and luciferase complementation assays to test protein interaction Results: With one of these enzymes, we observed a strong increase in PTM in the presence of Myoclonin- 1.Interestingly, the effect is observed even when a DM10 domain alone is co-expressed with the enzyme, suggesting for the first time a role for this domain. This suggests that Myoclonin1 may interact with and modulate the activity of this enzyme. By using luciferase complementation assay and pull down experiments, we could demonstrate that both proteins interact. Conclusions: Our data suggest Myoclonin-1 modulates specific PTM of MTs. This is of prime importance for microtubule dynamic and notably for neuroblast precursor migration during neocortex development. This could be the mechanism that explains why pathological forms of myoclonin-1 may affect brain development. [less ▲]

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See detailMethodology manual for European Association for Cardio-Thoracic Surgery (EACTS) clinical guidelines.
Sousa-Uva, Miguel; Head, Stuart J.; Thielmann, Matthias et al

in European journal of cardio-thoracic surgery : official journal of the European Association for Cardio-thoracic Surgery (2015), 48(6), 809-16

The goal of all clinical guidelines is to assist patients and practitioners in making healthcare decisions. However, clinical guidelines have been questioned about their quality, transparency and ... [more ▼]

The goal of all clinical guidelines is to assist patients and practitioners in making healthcare decisions. However, clinical guidelines have been questioned about their quality, transparency and independence. Based on the revision of manuals by other scientific cardiothoracic organizations, this document provides instructions for the development of European Association for Cardio-Thoracic Surgery (EACTS) clinical guidelines and other types of evidence-based documents. Four key areas have been addressed: (i) selection of taskforce members and transparency of relations with the industry, (ii) methods for critical appraisal of medical evidence, (iii) rules for writing recommendations and (iv) review process. It is hoped that, by adopting this methodology, clinical guidelines produced by the EACTS will be well balanced, objective and, importantly, trusted by physicians and patients who benefit from their implementation. [less ▲]

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See detailSwitch from Hashimoto Thyroiditis (HT) to Graves Basedow (GB) disease : a controlled study in a series of 15 patients
Maiga, I; BETEA, Daniela ULg; Geenen, Vincent ULg et al

in Abstract book - 20th Annual Congress of the Belgian Society of Internal Medicine (2015, December)

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See detailFamilial thyrogastric autoimmune syndrome : a study of 22 kindreds
Sid, Sélim ULg; LUTTERI, Laurence ULg; BEGUIN, Yves ULg et al

in Abstract book - 20th Annual Congress of the Belgian Society of Internal Medicine (2015, December)

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See detailSarcopenia as a public health problem
Bruyère, Olivier ULg; Beaudart, Charlotte ULg; Locquet, Médéa ULg et al

in European Geriatric Medicine (2015)

The importance of a health problem is based on its current and expected prevalence, its clinical and economic consequences, the social status of people affected by the problem and the availability of an ... [more ▼]

The importance of a health problem is based on its current and expected prevalence, its clinical and economic consequences, the social status of people affected by the problem and the availability of an effective treatment. In this paper, we review the main current literature on sarcopenia in order to assess whether this geriatric syndrome could be considered as a major public health problem. Our review highlights that based on its prevalence, its clinical consequences, the limitations of the current available treatments as well as on the fact that many frail patients are affected by this geriatric syndrome, sarcopenia should be considered as a health priority by all interested parties in order to reduce its burden. [less ▲]

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See detailAssessment of muscle mass, muscle strength and physical performance in clinical practice: An international survey
Bruyère, Olivier ULg; Beaudart, Charlotte ULg; Reginster, Jean-Yves ULg et al

in European Geriatric Medicine (2015)

Introduction: Several tools are available for the assessment of muscle mass, muscle strength and physical performance in clinical research. However, few data are available on the usage of these tools in ... [more ▼]

Introduction: Several tools are available for the assessment of muscle mass, muscle strength and physical performance in clinical research. However, few data are available on the usage of these tools in clinical practice. Methods: This study aimed to assess their usage by means of a large online international survey. Since sarcopenia is a specific condition where the assessment of muscle mass, muscle strength and physical performance is important, the survey also assessed the tools used for the diagnosis of this geriatric syndrome. Results: The survey was completed by 255 clinicians from 55 countries across 5 continents. Among these clinicians with geriatrics, rheumatology and endocrinology as major fields of interest, 53.3% assess muscle mass in daily practice, 54.5% muscle strength and 71.4% physical performance. However, the tools used are very different and no single tool is used by all clinicians. The tools and the cut-off values used by clinicians to diagnose sarcopenia are also heterogeneous. Conclusion: Because some tools used for the assessment of muscle mass, muscle strength or physical performance in daily practice are less validated than others, a greater awareness from the clinicians of the importance of using appropriate tools is needed [less ▲]

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See detailPrincipes pratiques de l'animatique des groupes. Stratégies d'animation en vue d'un apprentissage expérientiel
Faulx, Daniel ULg; Danse, Cédric ULg

in Cahiers Internationaux de Psychologie Sociale (2015), 4

he paradigm of the face-to-face group dynamics encloses the postulates, intentions and principles underlying group’s process. It formates the methodology of their conduct. Fourteen components of this ... [more ▼]

he paradigm of the face-to-face group dynamics encloses the postulates, intentions and principles underlying group’s process. It formates the methodology of their conduct. Fourteen components of this paradigm are here listed, to help the trainers, from the angle to apply it in their practical experience in leading groups. They make a consistent whole and guide the trainer in its using of the methodology of structured experiences. [less ▲]

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See detailExploring the bacterial diversity of Belgian steak tartare using metagenetics and qPCR analysis
Delhalle, Laurent ULg; Korsak Koulagenko, Nicolas ULg; Taminiau, Bernard ULg et al

in Journal of Food Protection (2015), 79(2), 200-229

Steak tartare is a popular meat dish in Belgium. It is prepared with raw ground minced beef and eaten with sauce, vegetables, and spiced. Since it contains raw meat, steak tartare is highly prone to ... [more ▼]

Steak tartare is a popular meat dish in Belgium. It is prepared with raw ground minced beef and eaten with sauce, vegetables, and spiced. Since it contains raw meat, steak tartare is highly prone to bacterial spoilage. The objective of this study was to explore the bacterial flora diversity in steak tartare in Belgium according to the source and to determine which bacteria are able to grow during the shelf life. A total of 58 samples from butchers’ shops, restaurants, sandwich shops and supermarkets were collected. These samples were analyzed using 16S rDNA metagenetics, a classical microbiological technique, and quantitative real-time PCR (qPCR) targeting the Lactobacillus genus. Samples were analyzed at the beginning and at the end of their shelf life, except for those from restaurants and sandwich shops analyzed only at the purchase date. Metagenetic analysis identified up to 180 bacterial species and 90 genera in some samples. But only seven bacterial species were predominant in the samples, depending on the source: Brochothrix thermosphacta, Lactobacillus algidus, Lactococcus piscium, Leuconostoc gelidum, Photobacterium kishitani, Pseudomonas spp. and Xanthomonas oryzae. With this work, an alternative method is proposed to evaluate the total flora in food samples based on the number of reads from metagenetic analysis and the results of qPCR. The degree of underestimation of aerobic plate counts (APCs) at 30°C estimated with the classical microbiology method was demonstrated in comparison with the proposed culture independent method. Compared to culture-based methods, metagenetic analysis combined with qPCR targeting Lactobacillus provides valuable information for characterizing the bacterial flora of raw meat. [less ▲]

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See detail“Public-based-Learning”: The Place of Publics in Exploring Environmental Controversies for Pedagogical Purposes
Melard, François ULg; Denayer, Dorothée ULg; Semal, Nathalie ULg

in International journal of environmental and Science Education (2015), 10(6), 905-920

This article examines a 15 year-old master level seminar dedicated to the exploration of local and complex environmental issues marked by scientific or technological uncertainties. Following a pragmatic ... [more ▼]

This article examines a 15 year-old master level seminar dedicated to the exploration of local and complex environmental issues marked by scientific or technological uncertainties. Following a pragmatic learning approach, we focus our discussion on a triadic relationship between supervisors, students and various concerned publics. A local flood management controversy in Belgium will help to illustrate our approach and point to some learning outcomes. On the basis of this pedagogical experience, we propose to shift from Problem-based-learning towards Public-based-learning that rests on the comparison of the various ways a problem is defined by publics. This comparative approach allows us to deduce a plurality of modes of involvement mobilized in the management of the environmental problems. [less ▲]

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See detailLe concept de réserve cognitive
Grotz, Catherine ULg; Adam, Stéphane ULg

Conference (2015, November 30)

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See detailLes insectes dans l'agriculture
Hatt, Séverin ULg; Francis, Frédéric ULg

Conference given outside the academic context (2015)

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