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See detailSmall-Angle Scattering in Porous Solids, an overview highlighting data analysis challenges
Gommes, Cédric ULg

Conference (2015, June)

Countless technologies and chemical processes make use of nanoporous materials: heterogeneous catalysis, including electrochemical reactions in fuel-cell electrodes, adsorption separation processes ... [more ▼]

Countless technologies and chemical processes make use of nanoporous materials: heterogeneous catalysis, including electrochemical reactions in fuel-cell electrodes, adsorption separation processes, kinetically selective membrane processes, are but a few examples. Nanopores are also relevant to natural processes as diverse as the weathering of rocks and ion transport through biological membranes.[1] Small-angle scattering of x-rays (SAXS) or neutrons (SANS) is one of the few experimental methods currently available for the in situ analysis of phenomena in this type of materials at the mesoscopic scale.[e.g. 2,3] In this presentation, we briefly review some recent applications of small-angle scattering to the in situ analysis of phenomena inside mesoporous solids. A particular focus is put on the data analysis challenges, whereby the scattered intensity is converted to real-space structures with nanometer resolution. [less ▲]

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See detailThe ICE protocol for ecological continuity: a new tool to evaluate the upstream fish passage success at physical barriers
Ovidio, Michaël ULg; Larinier, Michel; Burgun, Vincent et al

Conference (2015, June)

The recording and classification of obstacles that can interfere with the movements and migrations of fish is critical information to plan river restoration program. To date a major problem is to ... [more ▼]

The recording and classification of obstacles that can interfere with the movements and migrations of fish is critical information to plan river restoration program. To date a major problem is to determine the potential effect of each obstacle and to select the problematic sites that should be improved to restore longitudinal connectivity (construction of fish passage facilities, removal or modification of the obstacles). Fish passage success about an obstacle is complex and depends on the hydraulic conditions over and at the foot of the obstacle in relation to swimming and leaping capabilities of the fish species concerned. This selection and classification is too often biased because managers lack information’s on the fish capabilities to leap physical obstacles. The need for a simple, reliable and standardised assessment method for use by a wide range of environmental stakeholders rapidly became evident. We responded to the challenge and developed the ICE protocol as the basis for the required ecological-continuity assessment method, particularly in the context of the European Water Framework Directive implementation. The ICE protocol coordinated by ONEMA is based on an integration of the topographical and hydraulic characteristics of obstacles with the physical capabilities (swimming, jumping or crawling) of the fish species analysed. It requires the gathering of standardised descriptive variables on each obstacle. The result of the analysis is an indication on the risks of a structure constituting a more or less severe obstacle (5 classes) for a given fish species (n=47) or group of species. Particular attention was paid to the practical aspects of the method (time required and necessary human resources) to facilitate its use in a wide variety of situations and areas. Each procedure is presented as a flow chart to assist in decision-making, thus making the protocol easy to use for a wide range of people. [less ▲]

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See detailAdjusted Equivalent Static Wind Loads for non-Gaussian linear static analysis
Blaise, Nicolas ULg; Denoël, Vincent ULg

Conference (2015, June)

In this paper, we propose a parametric bi-cubic model for the joint probability distribution of wind aerodynamic pressures and structural responses. This non-Gaussian model is a bivariate extension of the ... [more ▼]

In this paper, we propose a parametric bi-cubic model for the joint probability distribution of wind aerodynamic pressures and structural responses. This non-Gaussian model is a bivariate extension of the well-known Hermite polynomial transformation. It offers a new way to determine Equivalent Static Wind Loads, with the embedded feature to –at least partly– capture the non-Gaussianity of the aerodynamic pressures and responses. In a second step, based on the observation that this model as well as the usual LRC method or the conditional sampling technique, fail in reproducing structural responses that do not overestimate the extreme values resulting from a complete structural analysis, we propose a two-step adjustment procedure that restores the non-overestimation condition and the recovery of the considered structural response. With the example of a boundary layer flow around a duo-pitched roof, it is demonstrated that the Equivalent Static Wind Loads, adjusted or not, obtained with the proposed model of non-Gaussian joint probability density function reconstruct the envelope of structural response more efficiently than with the other two techniques. [less ▲]

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See detailModeling inflorescence development in tomato
Périlleux, Claire ULg; Lobet, Guillaume ULg; Tocquin, Pierre ULg

Conference (2015, June)

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See detailThe Social (Re)construction of an Incident Reporting System: Opening-up, Closing-down, Starting over
Rossignol, Nicolas ULg

Conference (2015, June)

The literature on incident reporting generally describes Incident Reporting Systems (IRS) as technological tools aiming at improving safety in organizations by initiating a learning process from previous ... [more ▼]

The literature on incident reporting generally describes Incident Reporting Systems (IRS) as technological tools aiming at improving safety in organizations by initiating a learning process from previous events, in order to prevent future incidents and accidents to occur. In this respect, many studies tend to focus on “barriers to reporting” in order to understand why people report (or not) incidents in the dedicated system. Alternatively, we proposed to study IRS as socio-technical artifacts which are embedded in a specific organizational culture and which are interpreted in different ways, illustrating what has been called “interpretive flexibility”. This communication is divided in two parts. First, relying on the Social Construction Of Technology (SCOT) framework, we present the different practices and meanings attributed to the reporting of incidents within the Belgian Nuclear Research Center (SCK•CEN). We link these to the various modes of learning that they enable. By doing so we participate to the opening-up of the research on Incident Reporting to alternative discourses, practices and meanings, unforeseen situations and uncertainties. Second, we present the preliminary results of creative workshops during which we initiated the participatory re-construction of the IRS within the Center, drawing on and extending the results of the “opening-up” phase. By doing so, we aim at contributing to a transparent realization of the reduction of complexity leading to an informed and collective decision on what could/should be the IRS of the Center. In conclusion, we propose a reflexive analysis of this process, and we formulate tentative future research directions. [less ▲]

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See detailDoes yellow eel prefer old pool and weir or new vertical slot fish pass during their upstream migration?
Nzau Matondo, Billy ULg; Dierckx, Arnaud ULg; Benitez, Jean-Philippe ULg et al

Conference (2015, June)

The hydroelectric dam of Lixhe in the River Meuse, 323km upstream from the North Sea at the entry of Belgium near the frontier with the Netherlands is equipped with two basin fish-passes: – the old pool ... [more ▼]

The hydroelectric dam of Lixhe in the River Meuse, 323km upstream from the North Sea at the entry of Belgium near the frontier with the Netherlands is equipped with two basin fish-passes: – the old pool-and-weir configuration (OFP) operates at low discharge (0.13m3/s) and – the new vertical-slot configuration (NFP) operating at high discharge (1m3/s) with attraction flow (1.5m3/s). However, the utilization rate of these fish-passes by the incoming yellow eels remains unknown, because the trap of NFP is not adapted to retain anguillids and small species. Yet, such knowledge is crucial to improve the inland colonization of the species and to increase our understanding of fish-pass utilization given its particular swimming mode. In season 2013, eels caught two times a week using a cone-trap pool in the OFP and net traps in the NFP, were tagged and released the same day 0.3km downstream (n = 396eels). The utilization of OFP and NFP was studied using automatic RFID transponder detection antennas placed in upstream basins of the fish-passes, during years 2013 and 2014. Results revealed that the OFP was the preferred migration route of eels (eel numbers, OFP:NFP, 2013= 88:51 and 2014= 41:16, χ²-test, p<0.0001), which was also used earlier in season. Eels displayed fidelity to their catch fish-passes (>70% of the detected eels, annually). Detection rate was high in the year of eel tagging (2013: 35.1%) before decreasing in the following year (2014: 14.4%). Eels used these fish-passes the night from 22:00 to 04:00, at 14-26°C, river flow <200m³/s and whenever waxing and waning phases of moonlight. Our results provide insight into the utilization of fish-passes by migrating eels. The study suggests further reflection before removing the old fish-pass in large rivers and to think about the eel attractiveness and comfort when the construction of a new fish pass is planned. [less ▲]

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See detailOccupational physicians managing workers long-term sickness absence : are they willing to cooperate with family and social insurance physicians ?
Mairiaux, Philippe ULg; Vanmeerbeek, Marc ULg; Schippers, Nathalie ULg et al

Conference (2015, June)

Introduction In Belgium, sickness absence (SA) management implies complementary roles for family (FPs), social insurance (SIPs) and occupational physicians (OPs): FPs deliver sick notes, SIPs control SA ... [more ▼]

Introduction In Belgium, sickness absence (SA) management implies complementary roles for family (FPs), social insurance (SIPs) and occupational physicians (OPs): FPs deliver sick notes, SIPs control SA benefits and OPs strive to adapt work environments to workers’ capacities. In practice however, there is little cooperation between the three physicians. This study aimed at identifying FP-OP-SIP cooperation channels in order to prevent long-term work disability. Methods The study involved two phases. (1) Using the nominal group technique, researchers from the three physician groups reached a consensus on 15 proposals to enhance inter-professional cooperation. (2) A Delphi study was conducted to validate these proposals: 61 experts representing professional groups of physicians (FP, SIP, OP), patients, government, employers and labor unions were asked to participate. A 18-items questionnaire (the 15 proposals + 3 open questions) was used in a 2-round Delphi study. Proposals were accepted if 80% of experts agreed. Results Participation rate was 77% in round 1 and 7 out of the 15 proposals were accepted. During round 2, participation rate was 94%; 2 of the remaining proposals reached agreement level. Public authorities were thus advised to invest in a) promotion of pre-return to work visit with the OP for sick-listed patients; b) a website with OPs contact data; c) joint guidelines for return to work guidance; d) joint training of the 3 physician groups; 5) safe electronic information exchange. Several proposals aiming at giving work-related information to FPs and SIPs did not reach agreement within the OPs expert group. OPs expressed concerns about their own workload and FPs or SIPs ability to understand and use those information. Discussion The need for inter-physician cooperation in disability management may exceed individual goodwill and should best be organised by public authorities. This study may be a first step in this process. [less ▲]

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See detailNonlinear model updating by means of identified nonlinear normal modes
Song, Mingming; Renson, Ludovic ULg; Noël, Jean-Philippe ULg et al

Conference (2015, June)

Modal parameters are the most common features used for linear model updating. Although the modal analysis theory does not hold for nonlinear dynamic systems, its popularity encouraged researchers to come ... [more ▼]

Modal parameters are the most common features used for linear model updating. Although the modal analysis theory does not hold for nonlinear dynamic systems, its popularity encouraged researchers to come up with an equivalent version of normal modes for nonlinear systems, i.e., nonlinear normal modes (NNMs). A nonlinear system vibrates in NNMs when all masses have periodic motions of the same period, and at any time, the position of all the masses is uniquely defined by the position of any one of them. This paper investigates the feasibility of nonlinear model updating by minimizing the difference between the model-predicted and measured/identified nonlinear normal modes. A two degree-of-freedom mass-spring system with three linear springs and a cubic nonlinear spring is considered as the case study. The energy-dependent natural frequency and NNM of the first vibration mode of the system are identified at three different levels of energy. The stiffness parameters of the system are estimated by minimizing an objective function which is defined as the discrepancy between model-predicted natural frequency and NNM of the first mode, and their identified counterparts at the three measured energy levels. Performance of the proposed updating approach is evaluated at different levels of noise and different levels of modeling errors (i.e., nonlinear model classes). [less ▲]

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See detailLinking political discourses on science with an evolving and densely populated context: Exploring the prospects of Cultural Political Economy
Charlier, Nathan ULg

Conference (2015, June)

As a PhD student, I investigate the multiple ways science is conceived and valued in a research and innovation (R&I) policy context under seismic shifts (Tyfield, 2012): I aim at analyzing and comparing ... [more ▼]

As a PhD student, I investigate the multiple ways science is conceived and valued in a research and innovation (R&I) policy context under seismic shifts (Tyfield, 2012): I aim at analyzing and comparing the various political discourses about R&I in Flanders and Wallonia (the two main regions of Federal Belgium). With regards to that goal, I am currently in the process of analyzing a corpus of 33 semi-structured interviews with principal investigators of two University biotech research centers, with members of two University research management boards, and with representatives of two regional science policy advisory boards. In order to analyze this particular set of discourses, I build on various sensitizing concepts (van den Hoonard 1997) such as policy narratives (Radaelli, 2000), while following the tenets of Grounded Theory (Glaser & Strauss, 1967). However, it is, I believe, necessary to connect the specific discourses I am studying to a broader context made of institutions, of actors engaged in power relationships, of policies and policy reforms, of a specific history, of other discourses, etc. The way one build ties between a particular set of data and broader contextual aspects is key to a fruitful sociological analysis. My proposal is to explore the potentialities offered by Cultural Political Economy (Sum & Jessop, 2013), an approach concerned with “the relation between semiosis and structuration in political economy” (Sum & Jessop, 2013: X), when trying to link discourses on R&I to the context they are part of. Acknowledging the “interdependence and co-evolution of the semiotic and extra-semiotic” (ibid., 23), CPE offers heuristic tools to study the articulation of specific discourses “with technologies and agency” (ibid., 20). My communication will disclose the iterative process of discourse analysis relying on CPE, as well as its results. [less ▲]

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See detailA frequency-domain method for identifying nonlinear vibrating structures
Noël, Jean-Philippe ULg; Dossogne, Tilàn ULg; Kerschen, Gaëtan ULg

Conference (2015, June)

System identification, which refers to the construction of mathematical models from experimental data, plays a key role in the design process of engineering systems. In structural dynamics, the ... [more ▼]

System identification, which refers to the construction of mathematical models from experimental data, plays a key role in the design process of engineering systems. In structural dynamics, the theoretical and experimental aspects of linear system identification have been successfully addressed since the early seventies, and mature analytical, computational and testing tools have emerged. Nonlinear system identification of vibrating structures has also enjoyed significant advances during the past few years. However, the common practice in industry is to ignore nonlinearities, arguably because their analysis is still regarded as impractical. The present work describes a rigorous nonlinear generalisation in the frequency domain of the classical subspace identification algorithms, termed FNSI method. This method is applicable to large-scale systems comprising strong nonlinearities, closely-spaced modes and potentially high, nonproportional damping. Another distinct advantage of the approach is that it offers a convenient way to select an appropriate order for the nonlinear model by means of stabilisation diagrams. The FNSI method is demonstrated in this study using a complete satellite structure with nonsmooth nonlinearities, and a solar panel assembly exhibiting complex nonlinear stiffness and damping mechanisms. [less ▲]

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See detailImportance of the reconciliation method to handle experimental data: application to a reversible heat pump / organic Rankine cycle unit integrated in a positive energy building
Dumont, Olivier ULg; Quoilin, Sylvain ULg; Lemort, Vincent ULg

Conference (2015, June)

Experimental data is often the result of long and costly experimentations. Many times, measurements are used directly without (or with few) analysis and treatment. This paper therefore presents a detailed ... [more ▼]

Experimental data is often the result of long and costly experimentations. Many times, measurements are used directly without (or with few) analysis and treatment. This paper therefore presents a detailed methodology to use steady-state measurements efficiently in the analysis of a thermodynamic cycle. The reconciliation method allows to correct each measurement as little as possible, taking its accuracy into account, in order to satisfy all constraints and to evaluate the most probable physical state. The reconciliation method should be used for multiple reasons. First, this method allows to close energy and mass balances exactly, which is needed for predictive models. Also, it allows determining some unknowns that are not or that cannot be measured precisely. Furthermore, it fully exploits the collected measurements with redundancy and it allows to know which sensor should be checked or replaced if necessary. An application of this method is presented in the case of a reversible HP/ORC unit. This unit is a modified heat pump which is able to work as an organic Rankine cycle by reversing its cycle. Combined with a passive house comprising a solar roof and a ground heat exchanger, it allows to get a plus energy house. In this study case, the oil mass fraction is not measured despite of its strong influence on the results. The reconciliation method allows to evaluate it. The efficiency of this method is proven by comparing the error on the outputs of steady-state models of compressor and exchangers. An example is given with the prediction of the pinch-point of an evaporator. In this case, the normalized root mean square deviation (NRMSD) is decreased from 14.3 % to 4.1 % when using the reconciliation method. This paper proves the efficiency of the method and also that the method should be considered more often when dealing with experimentation. [less ▲]

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See detailHistorical evolution of fish biodiversity and capture periodicity in the River Meuse (Belgium) as revealed by 15 consecutive years of fishpass monitoring
Benitez, Jean-Philippe ULg; Dierckx, Arnaud ULg; Nzau Matondo, Billy ULg et al

Conference (2015, June)

In the River Meuse at 323km upstream from the North Sea, the hydroelectric dam of Lixhe (rated power of 5300KW) is equipped with two fishpasses: one pool and weir fishpass (in operation since 1980; 0.13m³ ... [more ▼]

In the River Meuse at 323km upstream from the North Sea, the hydroelectric dam of Lixhe (rated power of 5300KW) is equipped with two fishpasses: one pool and weir fishpass (in operation since 1980; 0.13m³.s-1 operating flow) and one vertical slot fishpass (in operation since 1998; 1m3.s-1 operating flow). Both fishpasses were scientifically monitored using capture traps during 15 consecutive years (from 1999 to 2014). The objective of the study is to analyse i) the evolution of fish stock and biodiversity over 15 years and ii) the capture periodicity of fish and it’s variation over years. During the considered period, we observed 36 species at adult stage (88597 individuals with 75% of cyprinids) and 13 species at juvenile (0+) stage (335067 individuals with 90% of cyprinids). Global results between 1999 and 2014 showed a drastic reduction in capture per year (>90%) for some species like Anguilla Anguilla, Alburnus alburnus, Blicca bjoerkna, Rutilus rutilus and Tinca tinca. Whereas other species have emerged like Aspius aspius and Silurus glanis. For the 0+, an important interannual variation is observed from few individuals to several tens of thousands per year. The comparison between both fishpasses indicated a greater use (>50%) of the vertical slot fishpass by rheophilic species and species that have good swimming ability. The analysis of capture periodicity for the most abundant species at adult stage demonstrated the presence of stable behaviours between years for the Abramis abrama and B. bjoerkna respectively a Q50 of the capture day of the year from 108th to 144th day at mean=17°C and from 118th to 155th day at mean=18°C. In contrast other species have patterns more variables (Barbus barbus: Q50 from 96th to 266th day; R. rutilus: from 10th and 309th day). Finally the 0+ exhibited a capture periodicity stable in time during the summer. [less ▲]

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See detailFavoriser l'émergence d'innovations institutionnelles dans la gouvernance des universités du Moyen-Orient: retour sur notre rôle de chercheur-intervenant dans un projet de collaboration internationale
Lisein, Olivier ULg; Pichault, François ULg

Conference (2015, June)

Cette communication revient sur un projet de recherche-action – visant à mettre en œuvre de nouveaux modes de gouvernance au sein de cinq universités d’Afrique méditerranéenne et du Moyen-Orient – que ... [more ▼]

Cette communication revient sur un projet de recherche-action – visant à mettre en œuvre de nouveaux modes de gouvernance au sein de cinq universités d’Afrique méditerranéenne et du Moyen-Orient – que nous avons géré pendant trois ans. A partir des enseignements que nous avons retirés de nos responsabilités dans ce projet collaboratif, nous proposons un regard réflexif sur notre position et notre rôle de chercheurs-intervenants invités à gérer un projet de recherche-action dans des contextes culturels auxquels nous n’étions pas habitués, avec des méthodologies implicatives pas nécessairement partagées par toutes les parties. Nous élaborons sur cette base différentes pistes d’explication potentielle aux difficultés méthodologiques que nous avons rencontrées et aux résultats contrastés que nous avons atteints. [less ▲]

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See detailA forecasting method using a wavelet-based mode decomposition and application to the ENSO index
Deliège, Adrien ULg; Nicolay, Samuel ULg; Fettweis, Xavier ULg

Conference (2015, June)

This work consists of a presentation and applications of a forecasting methodology based on a mode decomposition performed through a continuous wavelet transform. The idea is comparable to the Fourier ... [more ▼]

This work consists of a presentation and applications of a forecasting methodology based on a mode decomposition performed through a continuous wavelet transform. The idea is comparable to the Fourier series decomposition but where the amplitudes of the components are not constant anymore: the signal is written as a sum of periodic components with smooth time-varying amplitudes. This leads to a drastic decrease in the number of terms needed to decompose and rebuild the original signal without loss of precision. Once the decomposition is performed, the components are separately extrapolated, which leads to an extrapolation of the reconstructed signal that stands for a forecast of the original one. The quality of the forecast is assessed through a hindcast procedure (running retroactive probing forecasts) and Pearson correlations and root mean square errors are computed as functions of the lead time. This technique is first illustrated in details with a toy example, then with the El Niño Southern Oscillation (ENSO) time series. This signal consists of monthly-sampled sea surface temperature (SST) anomalies in the Eastern Pacific Ocean and is well-known to be one of the most influential climate patterns on the planet, inducing many consequences worldwide (hurricanes, droughts, flooding,…) and affecting human activities. Therefore, short-term predictions are of first importance in order to plan actions before the occurrence of these phenomena. As far as the ENSO time series is concerned, the wavelet-based mode decomposition leads to four components corresponding to periods of about 20, 31, 43 and 61 months respectively and the reconstruction recovers 97% of the El Niño/La Niña events (anomalous warming/cooling of the SST) of the last 65 years. Also, it turns out that more than 78% of these extreme events can be retrieved up to three years in advance. Finally, a forecast of the ENSO index is issued: the next La Niña event should start early in 2018 and should be followed soon after by a strong El Niño event in the second semester of 2019. [less ▲]

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See detailHydrodynamics, mixing and mass transfer in baffled stirred tanks
de Lamotte, Anne ULg; Delafosse, Angélique ULg; Calvo, Sébastien ULg et al

Conference (2015, June)

The present work presents CFD simulations of hydrodynamics, mixing and mass transfer in a surface-aerated baffled stirred tank. The modelling of the multiphase flow is realized via an Euler-Euler approach ... [more ▼]

The present work presents CFD simulations of hydrodynamics, mixing and mass transfer in a surface-aerated baffled stirred tank. The modelling of the multiphase flow is realized via an Euler-Euler approach. Three closure models are tested for the resolution of the RANS equations. When fully-developed flow field is reached, gas-liquid transfer is implemented with a local mass transfer coefficient estimated by the eddy cell model, and the temporal evolution of dissolved gas concentration is predicted.Hydrodynamic and mixing quantities as well as mass transfer parameters for the different turbulence models are compared with experimental data available for the same geometrical and operating features. A critical analysis of the prediction results allow to assess the models capabilities and to highlight the possible critical issues of the simulations. [less ▲]

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See detailGenetic depletion of the dual specificity protein phosphatase DUSP3 promotes LLC Lung tumour metastasis
Vandereyken, Maud ULg; Amand, Mathieu ULg; Van Overmeire, Eva et al

Conference (2015, June)

DUSP3, also called Vaccinia-H1 Related (VHR) is a small dual specificity phosphatase dephosphorylating both tyrosine and serine/threonine phosphorylated residues. DUSP3 plays an important role in cell ... [more ▼]

DUSP3, also called Vaccinia-H1 Related (VHR) is a small dual specificity phosphatase dephosphorylating both tyrosine and serine/threonine phosphorylated residues. DUSP3 plays an important role in cell cycle regulation and is up-regulated in several human cancers. The physiological role of this phosphatase is, however, poorly understood. We have recently generated a DUSP3 knockout mouse by homologous recombination. The obtained mice have no spontaneous phenotype or pathology. However, DUSP3 deficiency prevented neo-vascularization of subcutaneously transplanted Matrigel plugs and Lung Lewis Carcinoma (LLC) tumours, suggesting an involvement of DUSP3 in tumour angiogenesis. Considering the importance of angiogenesis in metastatic formation, our study aimed to investigate the role of DUSP3 in metastatic dissemination. To do so, we used the LLC experimental metastasis model that shortcuts the intravasation/extravasation processes by injecting intravenously the LLC and the B16 (metastatic melanoma cell line) cells. Surprisingly, LLC, but not B16, lung metastasis developed twice faster in DUSP3-KO than WT mice. The enhanced LLC metastatic growth in DUSP3-/- mice was transferable to WT mice via DUSP3-/- bone marrow adoptive transfer, suggesting an involvement of the hematopoietic compartment in the observed phenotype. This was confirmed by a higher infiltration of neutrophils and macrophages in the lungs of DUSP3-KO compared to WT mice after LLC injection. This infiltration was correlated with higher expression of the chemokine receptor CCR2 in LLC-bearing DUSP3-KO lungs macrophages. Interestingly, LLC, but not B16 cells, were found to secrete high level of CCL2/MCP1, the CCR ligand chemokine. In line with this observation, we found that DUSP3-/- bone marrow derived-macrophages have a higher migration potential in response to LLC, but not B16, -conditionned medium. Altogether, our results suggest that DUSP3 plays an important role in metastatic dissemination/growth by a mechanism involving the control of CCR2-CCL2 chemoattraction axis in macrophages. [less ▲]

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See detail“Elements of the Sublime (and the Grotesque) in Crime Fiction”
Dechene, Antoine ULg

Conference (2015, June)

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See detailAuroral Morphologies of Jupiter and Saturn
Grodent, Denis ULg

Conference (2015, May 31)

We review the principal differences and similarities of the morphologies of Jupiter and Saturn's auroral emissions. We then show some examples of UV images that are expected to be acquired with Cassini ... [more ▼]

We review the principal differences and similarities of the morphologies of Jupiter and Saturn's auroral emissions. We then show some examples of UV images that are expected to be acquired with Cassini UVIS at Saturn and Juno UVS at Jupiter. [less ▲]

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See detailComparing central western Europe Mesolithic and Neolithic plant processing microwear on flint tool
Linton, Jimmy ULg; Guéret, Colas; Gassin, Bernard

Conference (2015, May 30)

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See detailQuelles caractéristiques du passage à la retraite ont un impact sur la cognition du sujet âgé ? Résultats de la cohorte AMI
Grotz, Catherine ULg; Matharan, Fanny; Amieva, Hélène et al

Conference (2015, May 29)

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See detailDe l’ordre répressif étatique à celui de la Cour pénale internationale : la sensibilité du juge de Strasbourg à la gravité des faits en cause
Deprez, Christophe ULg

Conference (2015, May 29)

Cette présentation PowerPoint a servi de support à une communication orale dans le cadre de l'édition 2015 de la Conférence des Assistants en droit de Belgique (ACCA), organisée le 29 mai 2015 par l ... [more ▼]

Cette présentation PowerPoint a servi de support à une communication orale dans le cadre de l'édition 2015 de la Conférence des Assistants en droit de Belgique (ACCA), organisée le 29 mai 2015 par l'Université catholique de Louvain. [less ▲]

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See detailToward a more precise terminology for impact damage and an improved understanding of hunting weapons: First results from a large scale systematic experiment
Coppe, Justin ULg; Rots, Veerle ULg

Conference (2015, May 29)

Projectile points have recently taken an important place in debates on the complexity of Palaeolithic human behaviour. While the appearance of hunting weapons in the archaeological record was an important ... [more ▼]

Projectile points have recently taken an important place in debates on the complexity of Palaeolithic human behaviour. While the appearance of hunting weapons in the archaeological record was an important element in the past, current discussions focus a lot on the appearance of particular hunting methods. Distinctions are made between simple and complex weaponry, the latter assumed to be linked with modern humans only. While most of the identifications of hunting weapons in the archaeological record rely on the examination of so-called diagnostic impact damage, no reliable reference yet exist for distinguishing between hunting methods. We present the first results of a large-scale and systematic experiment that intends to address hunting weapons in a systematic way. A thorough survey of the literature has highlighted some existing ambiguity in current terminological frameworks for describing impact fractures. Based on our experiments, we propose some attributes that may be relevant for improving these terminologies. Attention will also be devoted to the design and conceptual framework of our experimental program and to some first results concerning the essential variables influencing damage formation. The overall goal is to improve our understanding of the different fracture phenomena and their variability in order to enhance the reliability of the identification of hunting weapons and perhaps of their projecting mode. [less ▲]

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See detailTowards an experiment based protocol for extracting and identifying residues
Cnuts, Dries ULg; Rots, Veerle ULg

Conference (2015, May 29)

Residue analysis has recently become a widely applied method in reconstructing the lifecycle of prehistoric stone tools. The identification of residues is traditionally based on the distinctive ... [more ▼]

Residue analysis has recently become a widely applied method in reconstructing the lifecycle of prehistoric stone tools. The identification of residues is traditionally based on the distinctive morphologies of the residue fragments by means of light microscopy. The majority of residue fragments, however, tend to have an amorphous structure and are therefore not easy to identify. In addition, some residue categories can only be detected by using transmitted light microscopy, which requires the extraction of residues from the tool’s surface. Yet another challenge is to determine whether the residues were deposited on the tool’s surface as a result of use or due to other processes. Here we present the results of an experimental study that addresses these methodological issues. Stone tools from a new experimental reference collection were used to test 6 different analytical methods: the observation of residues on stone tools with incident light microscopy, dry sampling using tweezers and brushes, wet sampling with micropipettes using distilled water and a tri-mixture of acetonitrile, ethanol and water, and extraction with an ultrasonic scaler or bath. The experiments demonstrate that the choice of a particular extraction procedure may influence the amount and types of residues that are extracted. This implies that the analytical method has an impact on the results of a residue analysis. Building on these data, we designed a new protocol, which was subsequently submitted to blind testing in order to test its accuracy and precision. Certain key attributes were also identified that may prove useful in distinguishing between use-related and natural residues. We discuss the importance of adapting analytical protocols to the research question of the study. [less ▲]

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See detailApproche processuelle de la dépression : Impact de processus psychologiques l'activation ou l'évitement en fonction du sexe
Wagener, Aurélie ULg

Conference (2015, May 29)

La dépression est caractérisée par des symptômes affectifs, cognitifs et somatiques. Elle est également caractérisée par une diminution du niveau d’engagement dans des activités ce qui peut être ... [more ▼]

La dépression est caractérisée par des symptômes affectifs, cognitifs et somatiques. Elle est également caractérisée par une diminution du niveau d’engagement dans des activités ce qui peut être conceptualisé comme de l’évitement comportemental (symptôme comportemental). Il est en effet fréquent que les patients dépressifs s’engagent de moins en moins dans des activités qui leur plaisaient auparavant (voir des amis, etc.) Ce faible niveau d’activités maintient leur humeur dépressive. Cette relation entre dépression et faible niveau d’engagement dans des activités est bien établie dans la littérature scientifique mais les relations entre les processus cognitifs sous-jacents sont encore mal connues. Selon les modèles théoriques de la dépression (Beck, 2008; Lewinsohn, 1985; Watkins, 2009), cinq types de processus psychologiques (PP) sont impliqués dans la symptomatologie dépressive : les pensées négatives répétitives, les stratégies de régulation émotionnelle non-adaptées, un faible niveau de satisfaction environnementale, une image de soi négative et une tendance à l’inhibition. Nous faisons l’hypothèse que ces PP pourraient être les facteurs explicatifs de l’évitement comportemental. Par ailleurs, nous faisons également l’hypothèse que d’autres PP pourraient être considérés comme des facteurs explicatifs de l’activation comportementale : les stratégies de régulation émotionnelle adaptées, un haut niveau de satisfaction environnementale, une image de soi positive, une tendance à l’approche et un concept de soi clair. Ces PP consisteraient en des facteurs protecteurs de la dépression. Dès lors, notre objectif est d’évaluer les liens entre évitement comportemental, activation comportementale et PP. Pour ce faire, en nous basant sur le modèle de Kinderman (2013), nous avons élaboré un modèle conceptualisant l’influence que peuvent avoir les PP précités sur, d’une part, l’évitement comportemental et, d’autre part, l’activation comportementale. De plus, l’étude évalue l’adéquation de ce modèle de façon à comparer les hommes et les femmes. 477 adultes issus de populations cliniques et non-cliniques (119 hommes, 358 femmes, âge moyen = 34,25, ET = 11,85) ont complété une étude en ligne évaluant les PP (pensées négatives répétitives, stratégies de régulation émotionnelles, satisfaction environnementale, image de soi, tendance à l’inhibition/l’approche, clarté du concept de soi), l’évitement comportemental et l’activation comportementale. Différents questionnaires évaluaient chacun de ces PP. Dès lors, des scores factoriels ont été réalisés pour représenter chaque PP. Les résultats préliminaires issus d’analyses factorielles confirmatoires semblent révéler des différences entre les hommes et les femmes. Pour les hommes, une image de soi négative, des stratégies de régulation émotionnelle non-adaptées et un faible niveau de satisfaction environnementale sont liés à l’évitement comportemental alors qu’un haut niveau de satisfaction environnementale et une image de soi positive sont liés à l’activation comportementale. Pour les femmes, un faible niveau de satisfaction environnementale, des stratégies de régulation émotionnelle non-adaptées et des pensées négatives répétitives sont liées à l’évitement comportemental alors qu’un haut niveau de satisfaction environnemental et une image de soi positive sont liées à l’activation comportementale. La collecte des données étant toujours en cours, les résultats globaux seront présentés durant le congrès. Les implications cliniques de ces résultats seront discutées telles que la pertinence de travailler sur le niveau de satisfaction environnementale. [less ▲]

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See detailAntitrust and The challenge of policing « moligopolists »
Petit, Nicolas ULg

Conference (2015, May 29)

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See detailIs Büchi's theorem useful for you?
Rigo, Michel ULg

Conference (2015, May 28)

Almost a century ago, Presburger showed that the first order theory of the natural numbers with addition is decidable. Following the work of Büchi in 1960, this result still holds when adding a function ... [more ▼]

Almost a century ago, Presburger showed that the first order theory of the natural numbers with addition is decidable. Following the work of Büchi in 1960, this result still holds when adding a function $V_k$ to the structure, where $V_k(n)$ is the largest power of $k\ge 2$ diving $n$. In particular, this leads to a logical characterization of the $k$-automatic sequences. During the last few years, many applications of this result have been considered in combinatorics on words, mostly by J. Shallit and his coauthors. In this talk, we will present this theorem of Büchi where decidability relies on finite automata.Then we will review some results about automatic sequences or morphic words that can be proved automatically (i.e., the proof is carried on by an algorithm). Finally, we will sketch the limitation of this technique. With a single line formula, one can prove automatically that the Thue-Morse word has no overlap but, hopefully, not all the combinatorial properties of morphic words can be derived in this way. [less ▲]

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See detailHeterogeneity of multitasking abilities in schizophrenia.
Laloyaux, Julien ULg; Van der Linden, Martial ULg; Laroi, Frank ULg

Conference (2015, May 28)

Difficulties in everyday life activities are core features of persons diagnosed with schizophrenia, and in particular for those activities requiring multitasking capacities. Multitasking refers to ... [more ▼]

Difficulties in everyday life activities are core features of persons diagnosed with schizophrenia, and in particular for those activities requiring multitasking capacities. Multitasking refers to activities (e.g. preparing a meal) where the person has to: (a) carry out and alternate between different tasks that vary in terms of priority, difficulty and duration; (b) define the tasks’ targets; (c) and face unexpected problems during the realization of these tasks. Moreover, schizophrenia is characterized by a great heterogeneity in regard to their everyday life difficulties and cognitive functioning. At present, patients’ multitasking capacities have not been adequately examined in the literature due to an absence of suitable assessment strategies. We thus recently developed a computerized real-life activity task designed to take into account the complex and multitasking nature of certain everyday life activities where participants are required to prepare a room for a meeting (i.e. the Computerized Meeting Preparation Task, CMPT). The aim of this study was to examine the multitasking abilities in persons diagnosed with schizophrenia and in particular the existence of subgroups of patients in regard to their performances on cognitive measures and on the CMPT. Sixty-two patients diagnosed with schizophrenia and 39 paired healthy controls completed the CMPT and a cognitive battery. The results reveal that the CMPT possesses good sensitivity and suggest three underlying constructs of multitasking (Memory, Planning and Intent), which were found to be underpinned by several cognitive functions and multitasking aspects. Moreover, cluster analyses revealed subgroups of patients differing in terms of their cognitive and CMPT performances. Taken together, these results show the need for a cognitive model of multitasking abilities in persons diagnosed with schiozphrenia. Taken together, this cognitive model and the CMPT, could be a good basis for cognitive interventions of multitasking abilities in schizophrenia. Finally, the results underline the heterogeneity of schizophrenia. [less ▲]

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See detailThe hot Jupiter WASP-­121 b: A planet heading towards its doom
Delrez, Laetitia ULg

Conference (2015, May 28)

We present here the discovery by the WASP-South survey, in close collaboration with the Euler and TRAPPIST telescopes, of WASP-121 b, a new remarkable short-period transiting hot Jupiter. WASP-121 b is a ... [more ▼]

We present here the discovery by the WASP-South survey, in close collaboration with the Euler and TRAPPIST telescopes, of WASP-121 b, a new remarkable short-period transiting hot Jupiter. WASP-121 b is a very inflated (1.86 Rjup) Jupiter-mass (1.18 Mjup) planet that transits every 1.27 days a bright active F6V star. A notable property of WASP-121b is that its orbital semi-major axis is only 15% larger than its Roche limit, which suggests that the planet might be close to tidal disruption. Furthermore, its large size and extreme irradiation (7.1 10^9 erg s^-1 cm^-2) make it an excellent target for atmospheric studies via secondary eclipse observations. Using the TRAPPIST robotic telescope, we indeed detect its thermal emission in the z’-band at better than ~4sigma, the measured occultation depth being 603+-130 ppm. This measurement is a first for a ground-based 60cm telescope. Finally, from a measurement of the Rossiter-McLaughlin effect with the CORALIE spectrograph, we infer a sky-projected spin-orbit angle of 257.8+-6 deg. This result indicates a significant misalignment between the spin axis of the host star and the orbital plane of the planet, the planet being in a nearly polar orbit. [less ▲]

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See detailLe donné phénoménal de Tim Crane
Gauvry, Charlotte ULg

Conference (2015, May 28)

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See detailThe more you know...........various approaches in the analysis of tools from Liang Bua, Flores Indonesia
Lentfer, Carol ULg; Stephenson, Birgitta; Cnuts, Dries ULg et al

Conference (2015, May 28)

Chipped stone flakes from sedimentary deposits from the Liang Bua site, Flores, Indonesia have been found in association with faunal remains and skeletal remains identified as Homo floresiensis. Use-wear ... [more ▼]

Chipped stone flakes from sedimentary deposits from the Liang Bua site, Flores, Indonesia have been found in association with faunal remains and skeletal remains identified as Homo floresiensis. Use-wear and well-preserved organic residues on these flakes provide an opportunity to understand subsistence and behaviour of Homo floresiensis by determining how they were manipulated and what they were used for. This paper describes the analytical techniques including various microscope and staining methodologies used in residue analyses. It compares the efficacy and describes the outcome of these techniques in relation to the functional analysis of the Liang Bua lithic assemblage. [less ▲]

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See detailStone tool hafting and use in the European Upper Palaeolithic: the first results of the analysis of Gravettian tools from Hohle Fels
Taipale, Noora ULg; Rots, Veerle ULg

Conference (2015, May 28)

European Upper Palaeolithic lithic assemblages have been so far defined largely on a typological or technological basis, while extensive studies that would utilise the full potential of microwear analysis ... [more ▼]

European Upper Palaeolithic lithic assemblages have been so far defined largely on a typological or technological basis, while extensive studies that would utilise the full potential of microwear analysis have been few. This contribution presents the first results of an ongoing PhD project dedicated to the variability in stone tool use and hafting in the Upper Palaeolithic of Central and Western Europe. The aim of the project is to understand the development as well as regional patterns in tool hafting and use in the Gravettian and Magdalenian, and thus better explain the observed morphological and technological shifts. For this purpose, samples of tools from five European key sites with well-dated sequences (Hohle Fels, Geißenklösterle, Vogelherd, Maisières-Canal, and Abri Pataud) will be analysed giving a special emphasis on hafting traces. The study wishes to promote functional analysis as an integral part of technological studies, not as a mere side note. The German cave site Hohle Fels is used here as a case study to illustrate the potential of this kind of approach. The first results of the analysis of the site’s Gravettian material will be put into a wider context of earlier published results as well as preliminary observations made on the other assemblages included in the present study. Building on these results, the impact of tool hafting and use on the morphology of Gravettian lithic implements will be discussed. [less ▲]

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See detailFully automated electrophoretically mediated microanalysis system for CYP1A1 activity monitoring
Farcas, Elena ULg; Servais, Anne-Catherine ULg; Lamalle, Caroline ULg et al

Conference (2015, May 28)

In order to evaluate the potentiality of capillary electrophoresis for CYP1A1 activity monitoring, an in-line method was developed with the well-known 7-ethoxycoumarin substrate. The electrophoretically ... [more ▼]

In order to evaluate the potentiality of capillary electrophoresis for CYP1A1 activity monitoring, an in-line method was developed with the well-known 7-ethoxycoumarin substrate. The electrophoretically mediated microanalysis approach was used with CYP1A1 supersomes to provide a rapid and fully automated method. The in-line homogenous enzyme assay was performed in physiological conditions (pH 7.4), whereas a MEKC buffer was used as background electrolyte. In order to reduce the analysis time, the short end injection was performed. Firstly a plug containing CYP1A1 supersomes was hydrodynamically injected into a fused silica capillary, followed by a plug of co-factor (NADPH) and substrate (7-ethoxycoumarin) and finally another plug of CYP1A1 (sandwich mode). The experimental conditions were finely investigated and tuned by design of experiment methodology. The metabolization rate measured in the optimized conditions was comparable with the one obtained after off-line metabolization. Finally, inhibition studies were conducted and a significant decrease of 7-hydroxycoumarin formation was observed using apigenin as CYP1A1 potent inhibitor. [less ▲]

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See detailAn ALE meta-analysis on the neural correlates of personal goal processing during episodic future thoughts and mind-wandering
Stawarczyk, David ULg; D'Argembeau, Arnaud ULg

Conference (2015, May 28)

The ability to project oneself into the future is a multi-determined mental faculty that depends on various cognitive processes supported by an extended set of brain regions. The aim of the present study ... [more ▼]

The ability to project oneself into the future is a multi-determined mental faculty that depends on various cognitive processes supported by an extended set of brain regions. The aim of the present study was to examine a crucial component of future thinking—personal goal processing—and to determine its neural correlates during both experimentally directed mental time travel towards the future and mind-wandering, a form of spontaneous thoughts characterized by a prospective bias towards upcoming events. To address this question, we performed three distinct ALE meta-analyses of brain imaging studies on episodic future thinking, mind-wandering, and personal goal processing. We then examined the commonalities and differences in brain activity between these three areas of research. The results showed that the three domains activated a common set of brain regions within the default network including the posterior inferior parietal cortex, posterior cingulate cortex, lateral temporal lobe, and, most notably, the medial prefrontal cortex. Differences in activation were also observed, and the medial prefrontal cortex was more activated during personal goal processing than the other two domains. These findings suggest that the medial prefrontal cortex mediates the processing of personal goals during both episodic future thinking and mind-wandering. [less ▲]

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See detailTool use and hafting in the Middle Palaeolithic of Northern Africa An on-going use-wear analysis on the Mousterian/Aterian assemblages of Ifri n’Ammar (Morocco)
Tomasso, Sonja ULg; Rots, Veerle ULg

Conference (2015, May 28)

The so-called “Aterian Culture” has received attention since the early days of prehistoric archaeology in Northern Africa. Several definitions were proposed, which triggered a debate around this cultural ... [more ▼]

The so-called “Aterian Culture” has received attention since the early days of prehistoric archaeology in Northern Africa. Several definitions were proposed, which triggered a debate around this cultural concept. In particular the presence of the tanged tools was a crucial element in these debates and the tangs were considered to potentially represent the earliest indications of hafting, or at least of intentional morphological adaptations in view of hafting. In contrast to numerous typological and technological studies of Aterian and Mousterian assemblages, use-wear analyses have been scarce up until today. However, for a better understanding of several aspects of these Middle Palaeolithic “cultures”, functional data needs to be taken into consideration. Given the issue of tanged pieces, the potential of such detailed studies on production, hafting and use is high. In this paper, the first results will be presented of an on-going use-wear analysis on tools from the Aterian/Mousterian assemblages of Ifri n’Ammar. This rock shelter presents an ideal case thanks to its particularly rich and well preserved stratigraphy. Around 200 artefacts have been selected up to now, based on their degree of preservation and without restrictions on the level of the tool types. Artefacts were examined macroscopically and microscopically in a search for evidence of their production, hafting and use and an experimental program was set up. Archaeological interpretations are based on new experiments, as well as on the existing large experimental reference collection available at TraceoLab at the University of Liège. The long-term goal of the study is to use a functional approach to answer questions related to lithic assemblage variability. At Ifri n’Ammar, it is clear that the tangs occur on a variety of tools. Due to the presence of tangs in the Aterian and their absence in the Mousterian, it can be hypothesized that there was a shift in hafting techniques between the two cultures/periods. In order to understand whether this change was triggered by functional, cultural, or environmental factors, more functional data is clearly needed. [less ▲]

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See detailQuelle place accorder aux écritures de la réception dans le contexte de la formation initiale? Du comportement des futurs enseignants face à des médiations de la lecture à l'élaboration de dispositifs de formation
De Croix, Séverine ULg; Ledur, Dominique

Conference (2015, May 28)

L’exploitation des écritures de la réception en formation initiale des enseignants fait aujourd’hui l’objet d’un large consensus (Joole, 2013 ; Chabanne & Dufays, 2011; Mazauric, Fourtanier & Langlade ... [more ▼]

L’exploitation des écritures de la réception en formation initiale des enseignants fait aujourd’hui l’objet d’un large consensus (Joole, 2013 ; Chabanne & Dufays, 2011; Mazauric, Fourtanier & Langlade, 2011 ; Vanhulle & Schillings, 2004). Nous souhaitons nous interroger sur les moyens, les objectifs et les effets attendus de cette exploitation (axe 4 de l’appel à communications). Le présent projet porte, dans un premier temps, sur l’observation des réactions d’une centaine de futurs enseignants de français du secondaire, tous niveaux confondus, face à un corpus de médiations écrites de la lecture, produites par des élèves de 12 à 18 ans, lecteurs experts et en difficulté. Ces écrits relèvent de genres diversifiés (journaux de lecture, notes critiques, traces collectées à l’occasion d’un dévoilement progressif, réponses à des questions, etc.) et de statuts différents (écrits de travail ou productions finales susceptibles d’être évaluées). Les consignes d’analyse devaient conduire les étudiants à repérer les éventuelles difficultés des lecteurs (ou leurs réussites), à reconstruire les tâches, à relever différents positionnements face aux textes, etc. Nos constats mettent notamment en évidence une tendance à investir ces écrits de façon normative (prédominance des difficultés du lecteur, notamment linguistiques, au détriment d’une prise en compte des difficultés générées par les textes et/ou les tâches scolaires) et une faible conscience de la complexité de l’activité de compréhension/interprétation. L’analyse des données collectées à l’occasion de ce travail incite, dans un deuxième temps, à privilégier quatre directions pour apprendre aux futurs maitres de lecture à lire des écrits de la réception et pour les amener par ce biais à développer des compétences et gestes professionnels en didactique de la lecture littéraire : modéliser l’activité de compréhension/interprétation, identifier les éventuelles difficultés de lecture, sélectionner des textes pour la classe et les associer à des médiations adaptées, percevoir les caractéristiques et les visées des tâches (y compris anticiper les éventuels malentendus générés par celles-ci et organiser leur progression). Ces axes d’intervention seront illustrés par quelques exemples de dispositifs de formation. [less ▲]

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See detailControl of nuclear sample polarization using optical pumping and radio-frequency methods
Lenaers, Florence ULg; Glover, Rohan ULg; Bastin, Thierry ULg

Conference (2015, May 27)

Laser-cooled and trapped radioactive isotopes are now being used to probe the properties of the weak interaction in nuclear beta decay. In this context, it is essential that one be able to control the ... [more ▼]

Laser-cooled and trapped radioactive isotopes are now being used to probe the properties of the weak interaction in nuclear beta decay. In this context, it is essential that one be able to control the nuclear polarization of the atomic samples. We present two polarization/depolarization schemes for argon-35, whose mirror transition to chlorine-35 is a particularly sensitive candidate for precision measurements in nuclear beta decay. [less ▲]

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See detailApplication du plan d’expérience de Box-Behnken et de la méthodologie des surfaces de réponses pour optimiser une méthode de quantification de phyto-œstrogènes dans les fourrages
Daems, Frédéric ULg; Lognay, Georges ULg; Romnee, Jean-Michel et al

Conference (2015, May 27)

Dans le cadre d’un projet de valorisation des prairies, intitulé « PhytoHealth », une méthode d’analyse quantitative constituée d’une étape d’extraction à l’aide d’un bain à ultrasons, suivi d’une ... [more ▼]

Dans le cadre d’un projet de valorisation des prairies, intitulé « PhytoHealth », une méthode d’analyse quantitative constituée d’une étape d’extraction à l’aide d’un bain à ultrasons, suivi d’une hydrolyse enzymatique et d’une analyse par UPLC®-MS/MS a été développée pour assurer le dosage de phyto-œstrogènes dans les fourrages. Pour alléger l’optimisation de la préparation des échantillons, la méthodologie des surfaces de réponses a été utilisée. Un plan d’expérience de Box-Behnken a été appliqué aux étapes d’extraction et d’hydrolyse. Parmi les différents facteurs pris en compte, les impacts de la nature du solvant utilisé lors de l’extraction ainsi que la température et le pH lors de l’hydrolyse, ont clairement pu être mis en évidence. L’ensemble des données générées a également permis de définir des conditions optimales d’extraction et d’hydrolyse pour chacun des composés. Ces conditions n’étant pas identiques pour chacun d’entre eux, un compromis a été trouvé afin de pouvoir analyser l’ensemble de ces composés simultanément. L’ensemble de la méthode a ensuite été validée selon les recommandations de l’EMA/CVMP/VICH/463202/2009, pour confirmer sa fiabilité et robustesse. Cette dernière, combinée au model d’ensilage en sacs sous vide, a permis pour la première fois de suivre la cinétique d’évolution de 4 phyto-œstrogènes (daidzéine, génistéine, formononétine et biochanin A) durant une période d’ensilage. [less ▲]

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See detailTel Quel, Change et Poétique en 1970 : "l'affaire de Lausanne"
Lorent, Fanny ULg

Conference (2015, May 27)

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See detailValidation d'une méthode d'analyse quantitative de l'équol par UPLC®-MS/MS dans le lait de vache - Application aux laits commercialisés en Wallonie (Belgique)
Daems, Frédéric ULg; Lognay, Georges ULg; Romne, Jean-Michel et al

Conference (2015, May 27)

Dans le cadre d’un projet intitulé «PhytoHealth », une méthode d’analyse quantitative de l’équol dans le lait a été développée et validée selon les recommandations de l’EMA/CVMP/VICH/463202/2009. Celle-ci ... [more ▼]

Dans le cadre d’un projet intitulé «PhytoHealth », une méthode d’analyse quantitative de l’équol dans le lait a été développée et validée selon les recommandations de l’EMA/CVMP/VICH/463202/2009. Celle-ci est constituée d’une étape d’hydrolyse enzymatique, suivie d’une double extraction liquide/liquide et d’une analyse par chromatographie liquide ultra performante couplé à un spectromètre de masse en tandem (UPLC®-MS/MS). Une fois les différents paramètres tels que la fiabilité, sensibilité et/ou robustesse de la méthode confirmées, celle-ci a permis, pour la première fois, d’estimer la teneur en équol d’ échantillons de laits commercialisés en Wallonie. Une Cinquantaine de laits ont été prélevés aléatoirement dans les commerces durant une période définie. Tous les échantillons possédaient une teneur en équol ≥ 10ng.mL-1. En comparant les valeurs moyennes, on a constaté qu’il n’y avait pas de différence entre les 4 catégories de laits analysés (entier, demi-écrémé, écrémé et cru). Par contre, une différence hautement significative a pu être observée entre les laits provenant de la filière biologique et ceux de la filière conventionnelle. Dans le premier cas, les teneurs varient entre 10 et 50 ng.mL-1 par contre, dans le second, elles varient entre 70 et 130 ng.mL-1. Cet impact de la filière biologique sur la teneur en équol dans les laits a pu être confronté à d’autres études européennes et confirmé. [less ▲]

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See detailDense-lineability in classes of ultradifferentiable functions
Esser, Céline ULg

Conference (2015, May 27)

The Denjoy-Carleman classes are spaces of smooth functions which satisfy growth conditions on their derivatives defined through weight sequences. In this talk, given a Denjoy-Carleman class E of Beurling ... [more ▼]

The Denjoy-Carleman classes are spaces of smooth functions which satisfy growth conditions on their derivatives defined through weight sequences. In this talk, given a Denjoy-Carleman class E of Beurling type that strictly contains another non-quasianalytic class F of Roumieu type, we handle the question of knowing how large the set of functions in E that are nowhere in the class $F$ is. In particular, we prove the dense-lineability of the set of functions of $E$ which are nowhere in F. Consequences for the Gevrey classes are also given. We extend then these results to the case of classes of ultradifferentiable functions defined imposing conditions on their Fourier Laplace transform using weight functions. [less ▲]

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See detailA stochastic multiscale analysis for MEMS stiction failure
Hoang Truong, Vinh ULg; Wu, Ling ULg; Golinval, Jean-Claude ULg et al

Conference (2015, May 26)

Stiction is a major failure in microelectromechanical system (MEMS) devices in which two contacting surfaces can remain stuck together because of the adhesive forces, such as van der Waals forces and ... [more ▼]

Stiction is a major failure in microelectromechanical system (MEMS) devices in which two contacting surfaces can remain stuck together because of the adhesive forces, such as van der Waals forces and capillary forces. Stiction is a multiscale problem which is characterized by three different lengths: the MEMS device characteristic length, the roughness of the contacting surfaces, and the distance range of the adhesive forces. Because MEMS surfaces roughness and adhesive force distances are of comparable scales, the randomness in the contacting surfaces can result in important uncertainties on the interacting forces, and in turn lead to a scatter in the MEMS structural behavior. The purpose of this work is to quantify the uncertainties on the macro stiction behavior of a MEMS structure due to the randomness in its contacting surfaces. A full analysis, such as the combination of a Monte-Carlo simulation to generate random surfaces combined with finite element (FE) analyses to model the stiction behavior, is expensive in terms of the computational cost due to the difference in the scales between the macro characteristic length and the distance range of the adhesive forces. Thus, in this work, we develop a stochastic multiscale analysis. At the micro scale, the uncertainties in the interacting forces between two rough surfaces are investigated. The power spectral density function of the surface is characterized from experimental topology measurements, and interacting surfaces are then generated as Gaussian random surfaces. For each generated random surface, the interacting adhesive forces are calculated by using a modified Dejarguin-Muller-Toporov (DMT) model. The resulting adhesive contact forces can be integrated using the finite element method at the structural scale by associating to each discretized contacting point a sampled surface. We then use the Monte-Carlo method to quantify the uncertainties in the stiction behavior of the MEMS device. [less ▲]

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See detailVenus nightglow intensity and solar activity: any correlation?
Soret, Lauriane ULg; Gérard, Jean-Claude ULg

Conference (2015, May 26)

We examine if any correlation is observed between the brightness of the O2 nightside airglow and the EUV solar irradiance using the full database of VIRTIS IR images. We conclude that, as was the case for ... [more ▼]

We examine if any correlation is observed between the brightness of the O2 nightside airglow and the EUV solar irradiance using the full database of VIRTIS IR images. We conclude that, as was the case for the NO airglow observed during the Pioneer Venus mission, no response to solar activity is observed. [less ▲]

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See detailPropagation of uncertainties in the modelling of MEMS resonators (using a 3-scale probabilistic approach)
Lucas, Vincent ULg; Wu, Ling ULg; Golinval, Jean-Claude ULg et al

Conference (2015, May 26)

In order to ensure the accuracy of MEMS vibrometers, the first resonance frequency should be predicted at the design phase. However, this prediction is subjected to randomness: there is a scatter in the ... [more ▼]

In order to ensure the accuracy of MEMS vibrometers, the first resonance frequency should be predicted at the design phase. However, this prediction is subjected to randomness: there is a scatter in the reached value resulting from the uncertainties involved in the manufacturing process. The purpose of this work is to take into account these uncertainties of the microstructure. The objective is a non-deterministic model that can be used since the design stage. The material is the source of uncertainties: the beam resonator is made of a polycrystalline material in which each grain has a random orientation. Solving the problem with a full direct numerical simulation combined to a Monte-Carlo method allows the probability density function of the resonance frequency to be computed. However this methodology is computationally expensive due to the number of degrees of freedom required to study one sample, motivating the development of a computationally efficient method. Towards this end a 3-scales stochastic model for predicting the resonance frequency of a micro-beam made of a polycrystalline linear anisotropic material is described. At the lower scale, we model the micro-structure with micro-volume elements. Due to the small-scale involved, the representativity of these micro-volume elements is not achieved and thus Statistical Volume Elements (SVE) are considered. These SVEs are generated under the form of a Voronoï tessellation, each grain being assigned a random orientation. Computational homogenization is applied over the SVEs, along with a Monte-Carlo procedure, to obtain a stochastic characterization of the elasticity tensor at the second scale of interest, the meso-scale. The spatial correlation between SVEs is also estimated. A generator based on spectral methods is implemented. Afterwards, using a stochastic finite element method, these meso-scale uncertainties are propagated by taking account of the spatial correlation up to the higher scale to predict the probabilistic behavior of the MEMS resonator. [less ▲]

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See detailDe la spécification à la création de nouvelles catégorisations sociales: Le cas de francophones vivant en Flandre et de néerlandophones vivant en Wallonie
Dassargues, Alix ULg

Conference (2015, May 26)

Nos recherches doctorales visent à étudier la manière dont des individus en situation d’allophonie « illégitime » se catégorisent socialement. Puisqu’aucune catégorie identitaire légitime (c.-à-d ... [more ▼]

Nos recherches doctorales visent à étudier la manière dont des individus en situation d’allophonie « illégitime » se catégorisent socialement. Puisqu’aucune catégorie identitaire légitime (c.-à-d. institutionnalisée par les dictionnaires, les médias, les politiciens ou autres instances légitimatrices (Bourdieu 1982)) ne rend compte de la situation de francophones vivant en Flandre (région belge unilingue néerlandophone) et de néerlandophones vivant en Wallonie (région belge unilingue francophone excepté une petite communauté germanophone institutionnellement reconnue et territorialisée), ces individus conceptualisent le champ social de façon originale afin qu’il corresponde à leurs propres expériences de vie (Harder 2010 : 18). En se basant sur des principes tels que la légitimité d’un lexème dans l’espace discursif ou encore le caractère idiolectal ou non d’une catégorisation, nous nous proposons d’observer les modes de conceptualisation de l’identité par des locuteurs particulièrement aptes à formuler des catégorisations originales du champ social puisque leurs expériences de vie ne font pas l’objet de catégorisations légitimes. À partir de transcriptions d’entretiens semi-directifs, nous avons examiné le discours de témoins afin d’analyser leurs conceptualisations du champ social à travers les catégorisations qu’ils emploient. Nous prenons en compte les catégories légitimes et illégitimes citées dans les témoignages selon leur institutionnalisation (présence ou non dans les dictionnaires et dans les discours médiatiques) et la manière dont elles sont considérées par les locuteurs (catégorie considérée comme légitime ou non par les locuteurs). De la sorte, une typologie de nouvelles catégorisations identitaires a pu être établie sur la base d’une analyse linguistique : spécification d’un lexème légitime par une proposition relative , spécification d’un signifié par un redoublement de certains signifiants légitimes , spécification d’un signifié par l’instauration d’une gradation dans l’adéquation avec une catégorie légitime (stéréotype institutionnalisé) , modifications de signifiés dans des catégorisations légitimes , création de nouvelles catégorisations à partir d’adjectifs et de lexèmes légitimes , création de métaphores en transposant l’expérience d’un domaine conceptuel des catégories sociales (cf. Lakoff & Johnson 1980). Cette recherche interdisciplinaire suggère que la construction de sens s’établit à partir d’autres connaissances déjà organisées entre elles (Harder 2010:113) et partagées par une communauté d’individus. En choisissant le thème ambitieux de l’identification (ou la catégorisation) de soi et des autres, cette recherche permet également de transposer les connaissances de la linguistique cognitive au domaine social. Ainsi, elle confirme notamment que le modèle sémantique basé sur un prototype (Rosch 1978; Lakoff 1987) est adéquat pour rendre compte de la construction individuelle du sens dans le champ social. [less ▲]

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See detailProcess-based method for groundwater resource vulnerability mapping with regards to solute contamination at the surface
Popescu, Cristina; Brouyère, Serge ULg; Orban, Philippe ULg et al

Conference (2015, May 26)

Numerous groundwater vulnerability methods have been developed taking into consideration a variable number of factors. The most common techniques are based on calculation of an index expressing the ... [more ▼]

Numerous groundwater vulnerability methods have been developed taking into consideration a variable number of factors. The most common techniques are based on calculation of an index expressing the protective effect of underground formations overlying the groundwater resource. However, it has been shown that different overlay and index methods applied to the same system can yield dramatically dissimilar results (among others, Gogu et al., 2003). The limitation of most of these methods is related to their use of a qualitative definition of groundwater vulnerability, as opposed to a definition based on a quantitative description of contaminant migration. A process-based point of view is proposed and based on three factors describing a pollution event (Brouyère et al., 2001): (1) the transit time from the source to the target, (2) the duration of the contamination breakthrough at the target, (3) the ratio between the maximum concentration at the target to the released concentration at the contamination source. The assessment can then be based on the impulse response at the ‘target’ to a Dirac-type solicitation (point, unit mass, instantaneous source of pollution), considering only physical hydrodispersive processes for intrinsic vulnerability and both physical and biochemical processes for specific vulnerability. The breakthrough curve obtained after a vertical transfer through the overlying layers can be computed pixel by pixel. Automatically processing the columns with identical characteristics, 1D partially saturated flow and solute transport computations are performed. Different maps are obtained for the three above mentioned factors. On the basis of these results, different vulnerability maps can be built according to the weighting coefficients agreed by the local community or decision makers. This concept allows a clear distinction between conventional aspects and process-based results in the building of a final vulnerability indicator. This methodology has the further advantage to consider the possible impact of runoff conditions occurring at the land surface and possibly leading to lateral contamination of groundwater through downstream preferential infiltration features. To solve this problem, Popescu et al. (2004 & 2008) and Dassargues et al. (2009) proposed a method for quantifying a lateral “dangerosity” coefficient using runoff coefficients based on land use, slopes, and soil properties. A test application is illustrated on a case-study located in a limestone basin in Belgium. [less ▲]

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See detailSensitivity and vulnerability to groundwater overexploitation by a ‘pressure state impact’ and process based approach
Beaujean, Jean; Lemieux, Jean-Michel; Therrien, René et al

Conference (2015, May 26)

A methodology is developed for proposing a groundwater vulnerability assessment in a Pressure-State-Impact causal chain that is familiar to decision makers. The ‘Driver Pressure State Impact Response’ ... [more ▼]

A methodology is developed for proposing a groundwater vulnerability assessment in a Pressure-State-Impact causal chain that is familiar to decision makers. The ‘Driver Pressure State Impact Response’ (DPSIR) framework, for describing interactions between society and the environment, defines a chain of Drivers that exert Pressures on the State of a given resource, such as groundwater, which then generates an Impact that will require an appropriate Response (Kristensen, 2004). The method is here based on the calculation of sensitivity coefficients for a user-defined groundwater state for which several physically-based indicators are proposed. These sensitivity coefficients reflect the easiness with which the groundwater state transmits pressures into impacts. They are grouped into a vulnerability matrix of pressures and impacts that quantify vulnerability for every combination of causal links identified in the DPSIR chain. For that reason, the sensitivity coefficients are converted to vulnerability, using the concept of ‘transgressing a given threshold’, which is commonly used in socioeconomic sciences (Luers et al. 2003). The concept of ‘rising above a given concentration threshold’ can be used for groundwater quality issues. The concept of ‘falling below a given piezometric head threshold’ can be used for groundwater quantity issues as aquifer overexploitation problems. Outside the careful selection of the sensitivity analysis method that can significantly influence the computational effort (Beaujean et al., 2013), emphasis is given to the illustration of the general methodology on a simple groundwater quantity case (of an alluvial aquifer with concerns related to water supply) demonstrating the potential use of this general and physically based vulnerability assessment method. While the methodology is general, the choice of causal chains has to be made prior to the calculation. The vulnerability is also related to a damaged state and is related to the ‘distance’ between the current state and a given threshold. This choice is arbitrary such that the vulnerability is sensitive to the choice of the threshold. [less ▲]

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See detailAbout the Regularity of Cantor's Bijection
Simons, Laurent ULg; Nicolay, Samuel ULg

Conference (2015, May 25)

In 1878, Cantor proved that there exists a one-to-one correspondence between the points of the unit line segment [0,1] and the points of the unit square [0,1]². Since this application is defined via ... [more ▼]

In 1878, Cantor proved that there exists a one-to-one correspondence between the points of the unit line segment [0,1] and the points of the unit square [0,1]². Since this application is defined via continued fractions, it is very hard to have any intuition about its smoothness. In this talk, we explore the regularity and the fractal nature of Cantor's bijection, using some notions concerning the metric theory and the ergodic theory of continued fractions. This talk is based on a joint work with S. Nicolay. [less ▲]

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See detailGestion des déchets nucléaires en France et en Belgique: Quelle place pour la critique ?
Parotte, Céline ULg

Conference (2015, May 25)

Depuis les années 1970, avec la multiplication des controverses scientifiques (Callon, Lascoumes et Barthe 2001), souvent liées à des mouvements pacifistes en environnementalistes ; nous assistons à la ... [more ▼]

Depuis les années 1970, avec la multiplication des controverses scientifiques (Callon, Lascoumes et Barthe 2001), souvent liées à des mouvements pacifistes en environnementalistes ; nous assistons à la naissance d’un flux d’incertitude et de critique politico-sociale, dirigée principalement vers le monde scientifique, sa production et ses hésitations. Il est malaisé de prévoir si cela mènera à une réelle désolidarisation des notions de science, technologie et progrès, mais il reste à supposer que cette critique permettra une gestion plus réflexive des effets majeurs du développement scientifique et technologique (Schot et Rip 2009). En d’autres termes, bien que les liens entre les idéologies du progrès et de la technologie restent très souvent puissants et non remis en question, on assiste au même moment à une critique sociale des conséquences sur le processus de gestion des choix technologiques qui s’y rapportent. Cette contribution propose de s’attarder sur le cas de la gouvernance socio technique de la gestion des déchets hautement radioactifs depuis le « tournant participatif » opéré dans les années 90 en France et en Belgique. Il s’agit de poser un regard critique sur l’apparition d’un nouveau mode de gouvernance plus participatif (au travers de l’inclusion de nouveaux acteurs) et ses conséquences. Dans quelle mesure ceux-ci redéfinissent-ils les positionnements du monde scientifique au sein du processus décisionnel ? Comment le monde scientifique reçoit-il les critiques qui lui sont adressées ? Plutôt que des tendances globales, cette contestation témoigne le plus souvent d’une mosaïque d’activités critiques dynamiques, concurrentes ou complémentaires dont les effets semblent faire vaciller — ou à tout le moins mettre sous tension — l’organisation, les routines et les institutions des sociétés modernes (Delvenne 2011). Cette mosaïque reflète le dynamisme des acteurs sociaux qui propagent leurs agendas et défendent leurs intérêts à travers la négociation de concessions, l’enchevêtrement de décisions et la cristallisation de rapports de force. En d’autres termes, les avancées d’un projet comme la gestion des déchets nucléaires ne sont pas la progression inéluctable d’un processus uniformément accepté par toutes les tendances de la société. En réalité, il existe une multitude d’acteurs qui influencent sans cesse la nature de ses contours. Ces acteurs sociaux bénéficient d’espaces politiques et institutionnels divers pour exprimer leurs préférences et tenter de transformer durablement les critiques qu’ils formulent en actions politiques qui trouvent un écho plus large au sein de la société. [less ▲]

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See detailCharles Juliet : Du portrait a-posteriori à l’écriture de soi L’adresse à la mère comme tentative de désenfouissement dans Lambeaux
Vandormael, Thomas ULg

Conference (2015, May 25)

Lambeaux propose un diptyque de portraits. Dans la première partie, celui de la mère biologique. Dans la seconde, celui de l’auteur lui-même et au sein de celui-ci, enfin, le portrait de la mère adoptive ... [more ▼]

Lambeaux propose un diptyque de portraits. Dans la première partie, celui de la mère biologique. Dans la seconde, celui de l’auteur lui-même et au sein de celui-ci, enfin, le portrait de la mère adoptive. La dimension vocative explicite de la narration en constitue à la fois l’originalité et le paradoxe. Le recours au « Tu » dans l’ensemble du texte fait advenir une poétique de l’adresse en laquelle se cristallise la spécificité du récit de filiation propre à l’autofiction de la littérature contemporaine : différent du simple devoir de mémoire ou encore de la - très en vogue - commémoration, il se situe plutôt du côté de la restitution, à laquelle il y a deux sens à donner : à la fois reconstituer ce qui fut et s’est défait, et rendre leur existence à ceux qui s’en sont trouvés dépouillés en faisant apparaître ce qui demeure enfoui et dont on n’a pu hériter. Pour répondre au silence d’une mère qu’il n’a pas connue et qui elle-même n’a pas pu s’exprimer, faute d’accès au langage ou d’une présence pour l’écouter, Juliet choisit l’instantané et l’immédiateté d’un discours d’interpellation au présent et la forme du dialogue avec les morts, forcément toujours en partie déjà voué à l’échec. Dès lors, notre propos souhaite interroger comment le choix du vocatif permet un dédoublement fécond du sujet,faisant advenir une relation de soi à soi qui déjoue les processus classiques de l'autobiographie. [less ▲]

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See detailElectric current crowding in nanostructured conductors
Silhanek, Alejandro ULg

Conference (2015, May 24)

When current stream lines are forced to depart from their rectilinear trajectory due to the presence of an obstacle, they conglomerate at the sharp bends encountered on their paths. The consequent current ... [more ▼]

When current stream lines are forced to depart from their rectilinear trajectory due to the presence of an obstacle, they conglomerate at the sharp bends encountered on their paths. The consequent current crowding is present in normal metals as well as in superconductors and has been, since long ago, identified as a key player in electromigration phenomena leading to failure in integrated circuit interconnects while might also be at the origin of local ablation in planar plasmonic structures. More recently, current crowding has been recognized as an important factor limiting the performance of superconducting single-photon detectors, leading to flux quanta motion rectification, or being a source of unwanted ratchet signal and depletion of surface barriers for magnetic flux penetration. In this talk, we will also show that in nanostructured superconductors at low temperatures, current crowding can trigger abrupt flux avalanches developing well defined geometrical patterns. Our experimental findings are backed up to the finest details, by simulations based on a phenomenological thermomagnetic model which, in turn, can be used to predict such complex structures and, given its reliability, allows one to estimate physical variables of more difficult experimental access, such as the local values of temperature and electric field. [less ▲]

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See detailDo large scale restoration projects reduce within-species traits variability?
Harzé, Mélanie ULg; Monty, Arnaud ULg; Mahy, Grégory ULg

Conference (2015, May 23)

Dry calcareous grasslands represent local biodiversity hotspots of European temperate regions. They have suffered intensive fragmentations due to due to the abandonment of traditional agropastoral systems ... [more ▼]

Dry calcareous grasslands represent local biodiversity hotspots of European temperate regions. They have suffered intensive fragmentations due to due to the abandonment of traditional agropastoral systems and the resulting encroachment, reforestation, urbanization or transformation into arable lands. In order to preserve and enhance their ecological value, a series of ecological restoration projects have been implemented throughout Europe (LIFE+). As habitats restoration costs can be prohibitive, actions should demonstrate their success. In the face of environmental changes, restored populations should possess attributes necessary for adaptive evolutionary changes allowing them to persist over the long term. Intra-population functional variability expresses the range of possible trait values of a species living in a heterogeneous environment. It results notably from genetic diversity and phenotypic plasticity and enables species survival, growth and reproduction under various environmental conditions. In Belgium, three European LIFE projects have taken place between 2000 and 2009, restoring more than 400 hectares of calcareous grasslands. Restorations have mainly been evaluated in terms of plant species diversity and community composition. Though it is expected to be of crucial importance for species evolutionary potential, the restoration of the entire range of environmental heterogeneity and the resulting intra-population functional variability of restored population have so far not been assessed. We compared the intra-population variability of functional traits (specific leaf area (SLA) and maximum vegetative height) of 10 restored and 10 reference populations of Potentilla neumanniana (30 individuals per populations). We characterized abiotic and biotic conditions by measuring soil depth, sun exposure, bare ground cover and mean vegetation height around each sampled individual. Our main results showed that the range of within-species functional variability was restored in our study area. We will conclude with implications for the evolutionary potential of restored populations and for future ecological restoration projects. [less ▲]

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See detailModulatory effects of Ruthenium (II)-based complexes on oxidative stress induced by activated HL60 cells and Neutrophils
Mouithys-Mickalad, Ange ULg; Collienne, Simon ULg; Franck, Thierry ULg et al

Conference (2015, May 22)

There is a growing interest on the use of metal-based chemotherapeutic agents to fight different types of cancers [1]. The most used family of the organometallic compounds is platinum derivatives whose ... [more ▼]

There is a growing interest on the use of metal-based chemotherapeutic agents to fight different types of cancers [1]. The most used family of the organometallic compounds is platinum derivatives whose Cisplatin (CisPt) is the lead compound used for the treatment of various cancers including lung, testis, gastric, breast, etc. Nevertheless, beside its recognized therapeutic effects, side effects such as gastric toxicity and acute kidney failure were observed during the treatment, limiting its clinical use. Other compounds are currently studied and among them, Ruthenium (Ru) complexes have gained more importance for their less toxicity and lower aggressive effect on healthy tissues than CisPt. Ru-complexes are also more resorbed and excreted [2]. Numerous studies focused on the mechanisms of action of Ruthenium compounds to fight cancer, including antioxidant or pro-oxidant activity. During inflammation, activation and infiltration of neutrophils contribute to oxidant stress playing a crucial role in tumor development. Likewise, the degranulation of neutrophil causes the release of myeloperoxidase (MPO) which reacts with H2O2 to catalyze redox reactions. A therapeutic target to control inflammation is the modulation of oxidant enzymes and cells involved in radical species production and redox reactions. Because Ruthenium compounds can easily enter into cancer cells, a series of Ru(II)-complexes newly synthesized were used for this purpose. They were first tested for their radical scavenging activities using ABTS and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays. Amongst them, compound 1 (LD0436) and compound 2 (LD04037) were then studied for their ability to modulate the reactive oxygen species (ROS) production by inflammatory cells like human promyelocytic leukemia cell line (HL 60) and neutrophils (PMN) using fluorescence, chemiluminescence (CL) and electron spin resonance ESR techniques. The toxicity of those Ru-complexes against HL-60 and neutrophils was checked using Trypan blue exclusion assay. Altogether, CL and ESR findings indicate that both complexes 1 (LD0436) and 2 (LD0437) exhibit a dose-dependent inhibitory activity compared to CisPt, gallic acid, curcumin and quercetin, which were taken as reference molecules in the different systems investigated. Similarly, the tested complexes also display an antioxidant profile on the substrate oxidation catalyzed by peroxidase such as MPO mainly involved in acute and chronic inflammatory situations. 1: (RuCl(p-Cymen)(S2C.IDip)]+(PF6)-], 2: (RuCl(p-Cymen)(S2C.Icy)]+(PF6)-] References: 1. Ceresa C, Brawin A, Cavaletti G, Trinidad A et al., (2014) Current Medicinal Chemistry 20(21), 2237-2265. 2. Liu, Y, Zhang X, Zhang R, et al., (2011) European Journal of Inorganic Chemistry. 1974-1980. [less ▲]

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See detailEffect of inulin and wheat bran in the creep feed of neonatal piglets
Li, Bing ULg; Leblois, Julie ULg; Bindelle, Jérôme ULg et al

Conference (2015, May 22)

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See detailAlain Robbe-Grillet face à l'entretien journalistique : paradoxes
Lorent, Fanny ULg

Conference (2015, May 22)

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See detailExploration de facteurs cognitifs et thymiques en lien avec les symptômes psychotiques : Analyses en clusters.
Laloyaux, Julien ULg; Laroi, Frank ULg; Nuyens, Filip et al

Conference (2015, May 22)

Introduction Il est maintenant reconnu qu’il existe différentes trajectoires possibles au développement et au maintien des symptômes psychotiques tels que les hallucinations et les idées délirantes. Ces ... [more ▼]

Introduction Il est maintenant reconnu qu’il existe différentes trajectoires possibles au développement et au maintien des symptômes psychotiques tels que les hallucinations et les idées délirantes. Ces phénomènes sont également en lien avec différents mécanismes cognitifs (e.g. style d’encodage, impulsivité) et facteurs thymiques (e.g. anxiété, dépression). Cependant, le poids de ces facteurs peut certainement varier en fonction des différentes trajectoires. Objectifs L’objectif de cette étude est d’explorer l’impact de différents facteurs cognitifs et thymiques sur les symptômes psychotiques dans un large échantillon issu de la population normale afin d’essayer d’en faire ressortir des profils différents avec l’aide d’analyses en clusters. Les mesures suivantes ont été incluses : Launay-Slade Hallucinations Scale, Schizotypal Personality Questionnaire-Brief, Peters et al. Delusions Inventory, UPPS Impulsive Behavior Scale, Beck Depression Inventory, State-Trait Anxiety Inventory (trait). [less ▲]

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See detailBifurcation Analysis of Large-Scale Dynamical Systems Using the Harmonic Balance Method
Detroux, Thibaut ULg; Renson, Ludovic ULg; Masset, Luc ULg et al

Conference (2015, May 22)

The harmonic balance (HB) method has been widely used in the past few years, as a numerical tool for the study of nonlinear industrial models. However, in its classical formulation the HB method is ... [more ▼]

The harmonic balance (HB) method has been widely used in the past few years, as a numerical tool for the study of nonlinear industrial models. However, in its classical formulation the HB method is limited to the approximation of periodic solutions. The present paper proposes to extend the method to the detection and tracking of codimension-1 bifurcations in the system parameters space. As an application, the frequency response of a spacecraft and its bifurcations are studied, together with two nonlinear phenomena, namely quasiperiodic oscillations and detached resonance curves. [less ▲]

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See detailMake the ureter your friend
Bonnet, Pierre ULg

Conference (2015, May 22)

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See detailQuels profils caractérisés par l'humeur, l'activation comportementale et les stratégies de régulation émotionnelle pouvons-nous identifier dans une population adulte ?
Wagener, Aurélie ULg

Conference (2015, May 22)

The behavioural model of depression put forward that the level of activities in depressed patients decreases which maintains their low mood. Depressed patients are also known to use non-adaptive cognitive ... [more ▼]

The behavioural model of depression put forward that the level of activities in depressed patients decreases which maintains their low mood. Depressed patients are also known to use non-adaptive cognitive coping strategies (e.g. rumination, catastrophizing). Previous research underlined that cognitive coping strategies predict the level of activation (non-adaptive cognitive coping strategies predict a low level of activation). According to the dimensional approach of psychopathology, we hypothesised that sub-groups of depressed and non-depressed adults could be identified depending on their level of activation and the kind of cognitive coping strategies they use. In order to test this hypothesis, we investigated the relationships between the level of activation, the cognitive coping strategies, anxiety and depression with a cluster-analysis approach. 762 adults (530 women, 232 men; mean age= 31.54, SD= 12.08) completed an online survey assessing the above-mentioned variables with self-reports measures (BADS-SF, CERQ, BDI-II, STAI-Y B). Results identified four clusters that differed according to the level of activation, the cognitive coping strategies, the anxiety and the depression. For instance, one of the four classes highlighted that non-active depressed adults used catastrophizing and rumination contrary to another classes of active non-depressed ones. These results, providing interesting guidelines for psychological interventions, will be discussed further during the congress. [less ▲]

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See detailAssessing employees propensity to engage in OCB: incremental validity of SJT beyond personality.
Lothe, Benoit ULg; Hansez, Isabelle ULg; Scius, Anthony et al

Conference (2015, May 21)

This study presents the validation results of a SJT developed in collaboration with a Belgian french speaking mutual insurance company for the assessment of employees OCB. The purpose is to provide ... [more ▼]

This study presents the validation results of a SJT developed in collaboration with a Belgian french speaking mutual insurance company for the assessment of employees OCB. The purpose is to provide empirical evidence concerning the validity of using the SJT by examining the issues of OCB criterion validity, incremental validity beyond a personality inventory, applicant perception and SJT transparency level. The SJT was developed in-house and following relevant literature recommendations (Weekley, Ployhart & Holtz, 2006). Data were collected on 117 white-collar employees. Three other measurements were concurrently collected: OCB using Williams & Anderson (1991) self-reported scales, personality using the Gosling, Rentfrow & Swann (2003) ten item inventory (TIPI) and applicant perception using SPJS (Bauer, & al., 2001). An open-ended question was used to access the extent to which applicants are able to identify the SJT criteria. Results indicated that the SJT is a relevant predictor of OCB (r = .42; p<.001). The SJT also provides incremental explanation of the OCB criteria beyond the personality inventory (∆R² = .11; p<.001). There was in average an agreement about the acceptability of the SJT in terms of perceived procedural justice. No relationships were found between applicant ability to correctly identify the SJT criteria and SJT score or OCB self-rating. This study is to our knowledge among the first attempt to develop and validate a tool to fill the gap on how to predict employees OCB (Organ, Podsakoff & Podsakoff, 2010). Implications for the personnel selection and current limitations will be discussed. [less ▲]

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See detailInvestigation of the consistency of the recent CH4 increase derived from NDACC-FTIR, ACE-FTS and GEOS-Chem
Bader, Whitney ULg; Conway, Stephanie; Strong, Kim et al

Conference (2015, May 21)

We present an update on the status of the recent methane increase study based on six FTIR ground-based sites, ACE-FTS satellite occultations and GEOS-Chem simulation.

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See detailAnatomy of the pelvis re-designed
Bonnet, Pierre ULg

Conference (2015, May 21)

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See detailLes circuits-courts en alimentation comme réponse au défi climatique
Ozer, Pierre ULg

Conference (2015, May 20)

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See detailStructural properties of densified GexSe1-x glasses
Yildirim, Can ULg; Micoulaut, Matthieu; Raty, Jean-Yves ULg

Conference (2015, May 20)

The evolution in structural properties of liquid and densified glassy GexSe1-x is investigated by use of First Principles Molecular Dynamics (FPMD) combined with X-ray absorption (XAS) experiments for the ... [more ▼]

The evolution in structural properties of liquid and densified glassy GexSe1-x is investigated by use of First Principles Molecular Dynamics (FPMD) combined with X-ray absorption (XAS) experiments for the glassy state. Four different compositions (x=10%, 16%, 18% and 33%) representing the flexible and stressed rigid sides of the reversibility window are the focus of the study. The target systems were studied at pressures up to ~ 11 GPa under both annealed and cold compression conditions. We examine the structure factors, pair distribution functions, bond angle distributions, coordination numbers and neighbor distributions. The results show that the real and reciprocal space properties are in very good agreement with the experimental findings. The structural evolution during densification reveals the edge sharing tetrahedra is maintained upon compression whereas Ge-Ge homopolar bonds tend to increase in number. Ge-Se-Ge bond angular distributions show a transformation from tetrahedral octahedral geometry. We discuss the effect of thermal history on structural properties during densification. [less ▲]

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See detailLa coopération Sud-Sud au sein des BRICS ; un nouveau paradigme d’aide au développement? Le cas du Brésil en Mozambique
Cusson, Gabrielle ULg

Conference (2015, May 20)

L’émergence et l’affirmation de nouvelles puissances dites du « Sud », dont celles des BRICS, ont donné un nouveau souffle à la coopération Sud-Sud (CSS), et ce spécialement en Afrique. Ces émergents ... [more ▼]

L’émergence et l’affirmation de nouvelles puissances dites du « Sud », dont celles des BRICS, ont donné un nouveau souffle à la coopération Sud-Sud (CSS), et ce spécialement en Afrique. Ces émergents jouissent d’une marge de manœuvre politique et économique grandissante qui leur permet de multiplier les partenariats Sud-Sud, de contribuer financièrement à la coopération au développement et d’instaurer de nouvelles structures d’institutionnalisation de CSS. La stratégie de CSS des BRICS se veut différente du modèle traditionnel de coopération Nord-Sud (CNS) ; elle s’appuie sur des principes de solidarité, offre une aide sans condition, se base sur des relations horizontales permettant des bénéfices mutuels pour les partenaires. Cependant, la CSS engagée par les BRICS n’est pas exempte de retombées politiques, diplomatiques ou commerciales à leur égard. Dans ce contexte, il est valable de se questionner à savoir si une politique de coopération au développement déployée par une puissance émergente peut être désintéressée et s’il est possible d’établir des relations d’égal à égal alors qu’elle se développe dans un cadre de rapports entre un donateur et un récepteur ? Cette présentation tentera de déterminer si le modèle de CSS soutenu par les BRICS s’inscrit dans un nouveau paradigme pour repenser l’efficacité de l’aide au développement en Afrique ou s’il reproduit la structure d’aide traditionnelle du modèle de CNS. Pour ce faire, nous étudierons le cas de la pénétration brésilienne au Mozambique, soit son implication technique et financière au développement de l’exploitation de certaines cultures à des fins de production de biocarburants. [less ▲]

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See detailCritical analysis and alternative treatment of Type Ia Supernovae data
Hauret, Clémentine ULg

Conference (2015, May 20)

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See detailChanges of macrofauna stable isotope compositions in a very inconstant seagrass detritic habitat: actual diet modification or baseline shift?
Remy, François ULg; Mascart, Thibaud ULg; Dauby, Patrick ULg et al

Conference (2015, May 20)

Decayed leaves of the Neptune grass Posidonia oceanica, detached and then exported during storms, constitute an important compartment in terms of organic matter transfer from the seagrass bed to the other ... [more ▼]

Decayed leaves of the Neptune grass Posidonia oceanica, detached and then exported during storms, constitute an important compartment in terms of organic matter transfer from the seagrass bed to the other habitats, particularly coastal habitats. These exported litter accumulations (ELA) support a diverse (more than 130 species) and abundant (up to 4900 id.m-2) vagile macrofauna (invertebrates > 500µm) assemblage which may play a key role in the degradation, enrichment and carbon transfer from P. oceanica dead material to coastal food chains. Indeed, preliminary results of vagile invertebrates gut content observations show that even if only a few of these species ingest a large proportion of P.oceanica dead leaves fragments, most of the others ingest a small but non-negligible part, suggesting a potential role of the whole community in the mechanical fragmentation of the dead leaves. ELA are very dynamic habitats with highly variable food availability, quality, and composition. Such an inconstant habitat may result in drastic modifications of the invertebrate community but also of its trophic structure and ecology. To test this hypothesis of influence of pulsed availability, quality and composition of food sources on the vagile macrofauna diet, we took seasonal samples in Calvi Bay (Corsica, 8°45’E; 42°35’N), at two sites between August 2011 and May 2012. Stable isotopes analysis (C&N) were conducted at an individual level on dominant macrofauna species and mixing and isotopic niche model packages in R were used. Bayesian inference “SIBER” package highlighted significant seasonal and spatial differences of diet at the community, specific and even intraspecific level. Data confirm the potential transfer of seagrass material to animal tissues but in various proportions depending of the species and the season. But one question remained: are these variations reflection a true diet change, or only a spatiotemporal baseline variation of the food sources isotopic composition? “SIAR” Bayesian mixing model showed that it depends on the species and that the two responses co-occur. We emphasized the need to work at the specific level but also with an adequate temporal resolution for sampling to encompass diet and baseline variability. [less ▲]

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See detailQuelles stratégies africaines face aux émergents?
Mputu Ingole, Jean-Claude ULg

Conference (2015, May 20)

Le rapprochement entre l’Afrique et les pays émergents pose toute une série des questions. Dans cet article, nous voulons nous interroger sur la position africaine face à ces nouveaux acteurs. Le ... [more ▼]

Le rapprochement entre l’Afrique et les pays émergents pose toute une série des questions. Dans cet article, nous voulons nous interroger sur la position africaine face à ces nouveaux acteurs. Le continent africain est-il un acteur conscient des enjeux en cours avec ces nouveaux « partenaires », pour reprendre les termes de l’Union Africaine, ou comme le suggère certains auteurs, elle serait entrain de subir une fois de plus la volonté des acteurs extérieurs ? Car si l’on constate que l’ensemble des pays émergents ont mis en place des nouvelles stratégies africaines, le contraire ne paraît pas évident. Ce papier se propose donc de voir s’il existe une ou plusieurs stratégies africaines vis-à-vis des émergents et si oui, de les analyser dans le contexte d’un monde en pleine mutation avec des nouveaux enjeux. Comment l’Union Africaine fait face aux nouvelles sollicitations des Etats émergents ? Compte-t-elle en tirer profit pour sa propre affirmation comme une actrice qui compte ou bien est-elle marginalisée par les Etats africains qui chacun, en ce qui le concerne, recherche ses propres intérêts. A-t-elle mis en place des nouveaux instruments pour gérer, selon ses intérêts cet accroissement de coopération avec les pays émergents. Quels rôles jouent les organisations régionales et/ou le NEPAD dans le développement de ces nouvelles coopérations ? Car au moment où la croissance africaine est l’une des plus fortes au monde et que le nombre de ses partenaires ne cesse d’augmenter, il est dès lors question de savoir comment l’Afrique se prépare à saisir ces nouvelles opportunités pour renforcer sa présence sur le monde avec ou sans les émergents. [less ▲]

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See detailL’influence normative de la Chine en Amérique latine, un défi stratégique pour l’Union européenne ?
Wintgens, Sophie ULg; Dabène, Olivier

Conference (2015, May 20)

La Chine est aujourd’hui devenue un partenaire commercial incontournable, un important pourvoyeur d’investissements directs étrangers et un grand fournisseur de prêts financiers pour un nombre croissant ... [more ▼]

La Chine est aujourd’hui devenue un partenaire commercial incontournable, un important pourvoyeur d’investissements directs étrangers et un grand fournisseur de prêts financiers pour un nombre croissant de pays d’Amérique latine. L’accroissement de ses échanges économiques et commerciaux avec ce sous-continent va de pair avec l’imposition des normes économiques et politiques dont sa politique commerciale internationale est porteuse. Cet article pose dès lors la question du défi que représente cette influence normative chinoise pour la stratégie déployée par l’Union européenne envers l’Amérique latine. [less ▲]

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See detailSimulations numériques sur des solides plongés, dans un contexte X-FEM
Duboeuf, Frédéric ULg; Béchet, Eric ULg

Conference (2015, May 20)

Ce travail traite des différents enjeux pour conserver toutes les capacités des calculs par éléments finis, en s’affranchissant des maillages conformes à la géométrie. La représentation de la géométrie ... [more ▼]

Ce travail traite des différents enjeux pour conserver toutes les capacités des calculs par éléments finis, en s’affranchissant des maillages conformes à la géométrie. La représentation de la géométrie, la construction d’un espace fonctionnel adapté et l’imposition des conditions aux limites sont abordées dans le contexte de la méthode des éléments finis étendus, tout particulièrement en présence de solides plongés dans un espace de dimension supérieure. L’approche proposée permet de traiter tout type de plongement, c.-à-d. des problèmes 1, 2, et/ou 3D plongés dans des maillages 2 ou 3D. [less ▲]

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See detailFrom the Hubble Space Telescope to Juno, unraveling the secrets of Jupiter's UV aurorae
Bonfond, Bertrand ULg

Conference (2015, May 19)

The successive generations of instruments on board the Hubble Space Telescope (HST) have revealed an increasing amount of details concerning the aurorae of Jupiter. Among the most striking results is the ... [more ▼]

The successive generations of instruments on board the Hubble Space Telescope (HST) have revealed an increasing amount of details concerning the aurorae of Jupiter. Among the most striking results is the finding that these aurorae are actually made of a multitude of components arising from a variety of processes, ranging from the local interaction of the Jovian moons with the magnetospheric plasma to solar-wind induced compression of the whole magnetosphere. In this presentation, I will review a few recent results obtained from Hubble Space Telescope observations. First, I will show how the morphology and the dynamics of the Ganymede footprint, i.e. the aurora on Jupiter created by the electromagnetic interaction between Ganymede and Jupiter, allowed us to infer the processes at play. Then, I will present results on the vertical profile of the auroral emissions and what they tell us about the acceleration of the electrons causing the auroral emissions. Furthermore, I will describe some of the short-timescale dynamics of the polar-most emissions, including their quasi-periodic nature. Finally, I will conclude with a short description of the expected outcome of the Juno mission, which will provide its first scientific results in fall 2016. [less ▲]

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