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See detailÉvaluation de la capacité du Modèle Atmosphérique Régional (MAR) à simuler la saison des pluies en Afrique Intertropicale
Doutreloup, Sébastien ULg; Wyard, Coraline ULg; Belleflamme, Alexandre ULg et al

in Dahech, Salem; Charfi, Sami (Eds.) Actes du XXXe colloque de l'Association Internationale de Climatologie : CLIMAT, VILLE ET ENVIRONNEMENT (2017, July)

In Intertropical Africa, climate is essentially characterized by the amount of precipitation and its annual regime. These precipitations and their evolution during the period 1970-1999 are simulated ... [more ▼]

In Intertropical Africa, climate is essentially characterized by the amount of precipitation and its annual regime. These precipitations and their evolution during the period 1970-1999 are simulated thanks to the Regional Atmospheric Model (MAR), developed at the ULg, and forced by the NCEP1 reanalyses and by the outputs of three global models (GCM) of the CMIP5 database. These MAR simulations are compared to the gridded data of the Climate Research Unit (CRU). It is clear from our investigations that the simulation of the MAR model forced by the NCEP1 reanalyses is better reproducing the quantities as well as the annual rainfall regime in the semi-arid regions than in equatorial regions. On the other hand, simulations of the MAR forced by the outputs of the GCMs are globally unsatisfactory throughout the intertropical domain in terms of quantities as well as the seasonality of precipitation. [less ▲]

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See detailEnhancing erythritol productivity in Yarrowia lipolytica using metabolic engineering
Carly, Frédéric; Vandermies, Marie ULg; Telek, Samuel ULg et al

in Metabolic Engineering (2017), 42

Erythritol (1,2,3,4-butanetetrol) is a four-carbon sugar alcohol with sweetening properties that is used by the agrofood industry as a food additive. In this study, we demonstrated that metabolic ... [more ▼]

Erythritol (1,2,3,4-butanetetrol) is a four-carbon sugar alcohol with sweetening properties that is used by the agrofood industry as a food additive. In this study, we demonstrated that metabolic engineering can be used to improve the production of erythritol from glycerol in the yeast Yarrowia lipolytica. The best results were obtained using a mutant that overexpressed GUT1 and TKL1, which encode a glycerol kinase and a transketolase, respectively, and in which EYK1, which encodes erythrulose kinase, was disrupted; the latter enzyme is involved in an early step of erythritol catabolism. In this strain, erythritol productivity was 75% higher than in the wild type; furthermore, the culturing time needed to achieve maximum concentration was reduced by 40%. An additional advantage is that the strain was unable to consume the erythritol it had created, further increasing the process's efficiency. The erythritol productivity values we obtained here are among the highest reported thus far. [less ▲]

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See detailFaire émerger les problèmes (présentation du dossier)
Gavray, Marc-Antoine ULg

in Diotime. Revue internationale de didactique de la philosophie (2017), 73

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See detailLe recours à l'arbitrage en matière de succession internationale ou la rencontre entre deux mondes qui s'ignorent
Wautelet, Patrick ULg

in Revue du Notariat Belge (2017), 143(3119), 378-405

L'arbitrage est-il possible et, si oui, dans quelle mesure, dans le domaine des successions internationales? Pour répondre à cette question, le texte prend appui sur le Règlement 650/2012. L’arbitrage ... [more ▼]

L'arbitrage est-il possible et, si oui, dans quelle mesure, dans le domaine des successions internationales? Pour répondre à cette question, le texte prend appui sur le Règlement 650/2012. L’arbitrage présente des avantages considérables pour régler les différends issus d’une suc- cession présentant une dimension internationale. Des obstacles importants peuvent néanmoins limiter, voire empêcher le recours à l’arbitrage en matière successorale. Sont abordées successivement dans cette contribution, les questions d'accès à l'arbitrage et de déroulement de l'arbitrage, en particulier sous l'angle du droit applicable à l'arbitrage successoral. Deux difficultés majeures seront examinées au titre des questions relatives à l'accès à l'arbitrage : la première tient à la possibilité pour une juridiction arbitrale de se prononcer sur les droits réservataires dont bénéficient certains proches du défunt, la seconde à la fragilité qui pèse sur le choix par un testateur de confier à une juridiction arbitrale la résolution des différends. [less ▲]

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See detailMIP-based constructive heuristics for the three-dimensional Bin Packing Problem with transportation constraints
Paquay, Célia ULg; Limbourg, Sabine ULg; Schyns, Michael ULg et al

in International Journal of Production Research (2017)

This article is about seeking a good feasible solution in a reasonable amount of computation time to the three-dimensional Multiple Bin Size Bin Packing Problem (MBSBPP). The MBSBPP studied considers ... [more ▼]

This article is about seeking a good feasible solution in a reasonable amount of computation time to the three-dimensional Multiple Bin Size Bin Packing Problem (MBSBPP). The MBSBPP studied considers additional constraints encountered in real world air transportation situations, such as cargo stability and the particular shape of containers. This MBSBPP has already been formulated as a Mixed Integer linear Programming problem, but as yet only poor results have been achieved for even fairly small problem sizes. The goal of the work this paper describes is to develop heuristics that are able to quickly provide good initial feasible solutions for the MBSBPP. Three methodologies are considered, which are based on the decomposition of the original problem into easier subproblems: the matheuristics Relax-and-Fix, Insert-and-Fix and Fractional Relax-and-Fix. They have been parametrised on real data sets and then compared to each other. In particular, two of these techniques show promising results in reasonable computational times. [less ▲]

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See detailViolences conjugales et justice pénale: un couple à problémes ? Introduction au dossier
Glowacz, Fabienne ULg; Vanneste, Charlotte ULg

in Champ Pénal = Penal Field (2017), Vol. XIV | 2017

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See detailImaging of super-fast dynamics and flow instabilities of superconducting vortices
Embon, L.; Anahory, Y.; Jelic, Zeljko ULg et al

in Nature Communications (2017), 8

Quantized magnetic vortices driven by electric current determine key electromagnetic properties of superconductors. While the dynamic behavior of slow vortices has been thoroughly investigated, the ... [more ▼]

Quantized magnetic vortices driven by electric current determine key electromagnetic properties of superconductors. While the dynamic behavior of slow vortices has been thoroughly investigated, the physics of ultrafast vortices under strong currents remains largely unexplored. Here, we use a nanoscale scanning superconducting quantum interference device to image vortices penetrating into a superconducting Pb film at rates of tens of GHz and moving with velocities of up to tens of km/s, which are not only much larger than the speed of sound but also exceed the pair-breaking speed limit of superconducting condensate. These experiments reveal formation of mesoscopic vortex channels which undergo cascades of bifurcations as the current and magnetic field increase. Our numerical simulations predict metamorphosis of fast Abrikosov vortices into mixed Abrikosov-Josephson vortices at even higher velocities. This work offers an insight into the fundamental physics of dynamic vortex states of superconductors at high current densities, crucial for many applications. [less ▲]

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See detailStructural Basis for Plant Plasma Membrane Protein Dynamics and Organization into Functional Nanodomains
Gronnier, Julien; Crowet, Jean-Marc ULg; Habenstein, Birgit et al

in eLife (2017), 6

Plasma Membrane is the primary structure for adjusting to ever changing conditions. PM sub-compartmentalization in domains is thought to orchestrate signalling cascades. Yet, mechanisms governing membrane ... [more ▼]

Plasma Membrane is the primary structure for adjusting to ever changing conditions. PM sub-compartmentalization in domains is thought to orchestrate signalling cascades. Yet, mechanisms governing membrane organization are mostly uncharacterized. The plant-specific proteins REMORINs are factors regulating hormonal crosstalk and host invasion. REMs are the best-characterized PM nanodomain markers targeted to the PM via an uncharacterized moiety called REMORIN C-terminal Anchor. By coupling biophysical methods, super-resolution microscopy and physiology, we decipher an original mechanism regulating the dynamic and organization of nanodomains. We showed that PM targeting is independent of the COP II-dependent secretory pathway and mediated by PI4P and sterol. REM-CA is an unconventional lipid-binding motif that confers nanodomain organization. Analyses of REM-CA mutants by single particle tracking demonstrate that mobility and supramolecular organization are critical for immunity. This study provides a unique mechanistic insight into how the tight control of spatial segregation is critical in the definition of PM domain necessary to support biological function. [less ▲]

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See detailAggregation of flexible domestic heat pumps for the provision of reserve in power systems
Georges, Emeline ULg; Quoilin, Sylvain ULg; Mathieu, Sébastien ULg et al

in Proceedings of the 30th International Conference on Efficiency, Cost, Optimisation, Simulation and Environmental Impact of Energy Systems. (2017, July)

The integration of renewable energy sources in the electricity production mix has an important impact on the management of the electricity grid, due to their intermittency. In particular, there is a ... [more ▼]

The integration of renewable energy sources in the electricity production mix has an important impact on the management of the electricity grid, due to their intermittency. In particular, there is a rising need for flexibility, both on the supply and demand sides. This paper assesses the amount of flexibility that could be reserved from a set of flexible residential heat pumps in a given geographical area. It addresses the problem of a load aggregator controlling a set of heat pumps used to provide both space-heating and domestic hot water. The flexibility of the heat pumps is unlocked in order to reduce electricity procurement costs in the day-ahead electricity market, while ensuring the provision of a predefined amount of reserve for real-time grid management. The objective of the paper is two-fold. On the one hand, an aggregation method of large sets of heat pumps based on physics-based models and random sampling techniques is proposed. On the other hand, a combined optimization problem is formulated to determine both the optimal electricity demand profile to be bought on the day-ahead market and the cost associated to the reservation of a defined amount of power. The method is applied to a set of 40000 residential heat pumps in Belgian houses. Results show that these houses can provide up to 100MW of upward reserve for 50% of the current costs. The provision of downward reserve at competitive cost is hampered by significant overconsumption. [less ▲]

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See detailIdentification and management of patients at increased risk of osteoporotic fracture: outcomes of an ESCEO expert consensus meeting.
Kanis, J.A.; Cooper, C.; Rizzoli, R. et al

in Osteoporosis International (2017), 28(7), 2023-2034

Summary: Osteoporosis represents a significant and increasing healthcare burden in Europe, but most patients at increased risk of fracture do not receive medication, resulting in a large treatment gap ... [more ▼]

Summary: Osteoporosis represents a significant and increasing healthcare burden in Europe, but most patients at increased risk of fracture do not receive medication, resulting in a large treatment gap. Identification of patients who are at particularly high risk will help clinicians target appropriate treatment more precisely and cost-effectively, and should be the focus of future research. Introduction: The purpose of the study was to review data on the identification and treatment of patients with osteoporosis at increased risk of fracture. Methods: Aworking group convened by the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis met to review current data on the epidemiology and burden of osteoporosis and the patterns of medical management throughout Europe. [less ▲]

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See detailMapping degenerate vortex states in a kagomé lattice of elongated antidots via scanning Hall probe microscopy
Xue, Cun; Ge, Jun-Yi; He, An et al

in Physical Review. B : Condensed Matter (2017), 96

We investigate the degeneracy of the superconducting vortex matter ground state by directly visualizing the vortex con gurations in a kagomé lattice of elongated antidots via scanning Hall probe ... [more ▼]

We investigate the degeneracy of the superconducting vortex matter ground state by directly visualizing the vortex con gurations in a kagomé lattice of elongated antidots via scanning Hall probe microscopy (SHPM). The observed vortex patterns, at specifi c applied magnetic fi elds, are in good agreement with the confi gurations obtained using time-dependent Ginzburg-Landau (TDGL) simulation. Both results indicate that the long range interaction in this nano-structured superconductor is unable to lift degeneracy between different vortex states and the pattern formation is mainly ruled by the nearest neighbour interaction. This simpli cation allows the identi cation of a set of simple rules characterizing the vortex con gurations. We demonstrated that these rules can explain both the observed vortex distributions and the magnetic fi eld dependent degree of degeneracy. [less ▲]

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See detailFish learned movements in a large regulated river
Capra, Hervé; Pella, Hervé; Ovidio, Michaël ULg et al

Conference (2017, July)

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See detailA field quantification of all inclusive fish-pass efficiency using a combined telemetry system
Ovidio, Michaël ULg; Sonny, Damien; Dierckx, Arnaud ULg et al

Conference (2017, July)

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See detailFish habitat selection in a large hydropeaking river: strong individual and temporal variations revealed by telemetry
Plichard, Laura; Capra, Hervé; Pella, Hervé et al

Conference (2017, July)

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See detailConsistency of spatiotemporal sound features supports the use of passive acoustics for long-term monitoring
Parmentier, Eric ULg; Di Iorio, Lucia; Picciulin, Marta et al

in Animal Conservation (2017)

Many studies stress the usefulness of fish calls as effective indicators of distinct species occurrence. However, most of these studies have been undertaken in a given area and during restricted periods ... [more ▼]

Many studies stress the usefulness of fish calls as effective indicators of distinct species occurrence. However, most of these studies have been undertaken in a given area and during restricted periods of time. There is a need to show passive acoustic monitoring is a reliable method to study vocal species over space and time. This study aims to use passive acoustic methods to follow the brown meagre Sciaena umbra at relevant temporal and spatial scales. Specimens of S. umbra were recorded in both aquarium and in the field. In situ recordings were made at two regions (Corsica and Sardinia) during four summers (2008–2012–2013–2015). Temporal and frequency parameters of the fish calls were collected by different teams and compared to test the ability to unequivocally identify the fish sound. The comparison between our data and the bibliography highlights the capability to identify S. umbra during a period of 17 years in different Mediterranean regions, clearly supporting the usefulness of acoustic monitoring to discover and protect aggregation sites of this endangered species. The sound producing mechanism in S. umbra consists of high-speed sonic muscles surrounding dorsally the posterior end of the swim bladder, which can explain the low acoustic variability that helps in the species identification. Similar mechanisms are found in other Sciaenidae, suggesting that a similar conclusion can be drawn for many other adult sciaenids that could be used as sentinel species. This study should be of high interest to policymakers and scientists because it shows passive acoustic can be confidently used in resource management. [less ▲]

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See detailViolences au sein des relations amoureuses des adolescents et jeunes adultes : une réalité à ne pas négliger
Glowacz, Fabienne ULg; Courtain, Audrey ULg

in Champ Pénal = Penal Field (2017), XIV

Au cours des dernières décennies, la violence conjugale a fait l’objet d’un intérêt majeur par la science et la société, donnant lieu à l’élaboration de textes légaux et à des stratégies judiciaires ... [more ▼]

Au cours des dernières décennies, la violence conjugale a fait l’objet d’un intérêt majeur par la science et la société, donnant lieu à l’élaboration de textes légaux et à des stratégies judiciaires, psycho-sociales et préventives spécifiques. Ces avancées ont été initiées par la mobilisation des mouvements féministes qui ont sensibilisé la société aux violences faites aux femmes, tout particulièrement la violence physique, pour ensuite également considérer différentes formes de violences. Ainsi, les recherches scientifiques et les politiques publiques se sont concentrées principalement sur les violences dans les couples entre partenaires adultes. La violence dans les relations amoureuses des adolescents et des jeunes adultes est peu envisagée à un niveau sociétal, alors que la recherche montre que différentes formes de violences sont présentes au sein de ces relations. Dans le cadre de cette contribution, nous proposons de développer sur base d’une revue de la littérature et de données d’enquêtes menées auprès d’adolescents et de jeunes adultes, les spécificités des violences au sein des relations amoureuses durant cette période de développement, leurs prévalences et les dynamiques en cours, ainsi que les iens entre attitudes et violences agies et subies dans les relations amoureuses. Les questions relatives à la bidirectionnalité et à la symétrie de la violence, débattues pour la violence conjugale, seront également discutées à la lumière des éléments émanant des recherches menées au niveau international et d’une enquête menée en Belgique. [less ▲]

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See detailHydro-mechanical modelling of a coalbed methane production well via a dual-porosity approach
Bertrand, François ULg; Buzzi, Olivier; Collin, Frédéric ULg

in Book of Abstracts: 6th International Conference on Coupled THMC Processes in Geosystems (2017, July)

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See detailBeta Cell Regeneration in Zebrafish : Investigating the Ductal Contribution
Bergemann, David ULg; Massoz, Laura; Bourdouxhe, Jordane ULg et al

Poster (2017, July)

Diabetes is characterized by the loss of insulin producing beta cells. Although different therapeutic strategies do exist, they lack precise and dynamic control of glycemia as carried out by endogenous ... [more ▼]

Diabetes is characterized by the loss of insulin producing beta cells. Although different therapeutic strategies do exist, they lack precise and dynamic control of glycemia as carried out by endogenous beta cells. One promising alternative is to replenish the pancreas with bona fide functional beta cells by triggering regeneration mechanisms. Previous studies have shown beta cell neogenesis originating from different pancreatic cell types (alpha, delta, acinar and ductal cells), depending on the used model. The ductal origin is supported by the fact that the embryonic duct epithelium gives rise to the endocrine lineage, and that in healthy and diabetic human adults, insulin positive cells could be found next to or in pancreatic ducts. Despite these observations, mammals show very limited regenerative capabilities, making it difficult to investigate those mechanisms. In contrast, zebrafish are extensively used for regeneration studies. The ability of adult zebrafish to regenerate its beta cells and restore normoglycemia after massive beta cell ablation has already been shown. We, and other groups, have previously shown that adult pancreatic duct cells act as progenitors, giving rise to beta cells in physiological and induced diabetic condition in vivo. To get insight into this process, we conducted comparative RNA-seq experiments on pancreatic duct cells from adult zebrafish. By this means, we identified regulated gene expression that can be linked to specific processes/pathways such as cell cycling and Notch. In order to confirm the involvement of identified candidate genes/pathways, we are setting up a screening method using chemical activators and inhibitors in old larvae, by looking at their ability to modify proliferation/differentiation of duct cells after beta cell ablation. In addition, we are also investigating the effect of mutations, generated by the CRISPR/Cas9 system within candidate genes, on the regeneration capabilities. Together, these strategies should provide new clues about regenerative processes triggered in duct cells that might be applied to overcome the poor regenerative capabilities of mammals. [less ▲]

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See detailOptimising workforce and energy costs by exploiting production flexibility
Cuvelier, Thibaut ULg; Louveaux, Quentin ULg

Conference (2017, July)

In a world where the electricity prices become more and more volatile, notably due to renewable energies, the industry is suffering from cost variations never seen before, especially when electro ... [more ▼]

In a world where the electricity prices become more and more volatile, notably due to renewable energies, the industry is suffering from cost variations never seen before, especially when electro-intensive. Nevertheless, the plants can significantly reduce this impact: some electro-intensive factories could shift their production to time periods where the electricity is cheaper, resulting in large savings. At the same time, the grid operator can remunerate this consumption adaptation as a flexibility service. Our research goal is to optimise the operations of a factory around this flexibility. We compute a production plan that adapts to price forecasts, but also flexibility levers that adjust this plan to react to unexpected price changes. We propose the unifying concept of reservoir to provide sufficiently good models for the plant's processes. Nevertheless, this methodology implies to have frequent production plan changes, which directly impacts the workers, as they may be asked to follow barely predictable schedules. This has a significant detrimental effect on their quality of life. As a consequence, the human aspect of flexibility must also be considered: we seek for production plans that consider both workforce and energy costs, and we then assign workers to work shifts while ensuring their well-being. This HR orientation is the most innovative contribution of this research project. [less ▲]

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See detailThe question of the methane increase through the retrieval of its isotopologues from FTIR ground-based observations
Bader, Whitney ULg; Strong, Kimberley; Walker, Kaley

Poster (2017, July)

Methane (CH4) is the second most important greenhouse gas emitted by human activities in the Earth’s atmosphere. Although it is roughly 200 times less abundant than carbon dioxide, it is a 28 times more ... [more ▼]

Methane (CH4) is the second most important greenhouse gas emitted by human activities in the Earth’s atmosphere. Although it is roughly 200 times less abundant than carbon dioxide, it is a 28 times more potent greenhouse gas. Approximately one fifth of the changes in the Earth’s balance energy caused by human-linked greenhouse gases since the beginning of industrialization (~1750) is due to methane. Methane is emitted by both natural sources and human activities. Indeed, methane can be emitted to the atmosphere through coal mining, oil and gas exploitation, rice cultures, domestic ruminant animals, biomass burning, waste management, wetlands, termites, methane hydrates and ocean. Since the beginning of the industrialization, atmospheric methane concentrations have increased by 260% to reach 1824 pbb in 2013. From the 1980s until the beginning of the 1990s, atmospheric methane was significantly on the rise, then stabilized during 1999-2006 to rise again afterwards. To this day, the source or sink responsible of this latter increase remains unexplained. Through each emission process, heavy molecules of methane (with one additional neutron either on a carbon or on one hydrogen atom) are emitted along methane (12CH4). The main heavy molecules of methane, called isotopologues (13CH4 and CH3D), are respectively ~110 and ~60 000 times less abundant than methane. Despite their small abundances, they give crucial information on the concentration of methane in the atmosphere and its evolution. Indeed, both isotopologues are emitted with specific emission ratio depending on the emission sources. Determining isotopic ratio of atmospheric methane is therefore a unique tracer of its budget. While the non-monotonous trend of methane is subject of an extensive number of studies, to our knowledge, no study of the isotopic ratio of methane derived from ground-based solar observations has been published to date. Measurements of heavy methane from Fourier Transform InfraRed spectra recorded with state of the art spectrometers installed at Eureka [Arctic, Canada] and Toronto [Ontario, Canada] will help fill this gap. Indeed, the produced time series will ease data interpretation and contribute to a global view of the question of isotopologues. [less ▲]

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