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See detailInference in a stochastic SEIR model using Sequential Monte Carlo methods
Bonou, Wilfried ULg; LAMBERT, Philippe

in The 37th Annual Conference of the International Society for Clinical Biostatistics (ISCB): Book of Abstracts. Birmingham, UK, 21-25 August 2016 (2016, August)

Many biological, physical, chemical, economic, and social phenomena are dynamic and are modeled using (systems of) Ordinary Differential Equations (ODEs). But a more realistic way to describe these ... [more ▼]

Many biological, physical, chemical, economic, and social phenomena are dynamic and are modeled using (systems of) Ordinary Differential Equations (ODEs). But a more realistic way to describe these dynamics relies on Discrete Time Markov Chains (DTMC). There is a growing interest in the development of Bayesian statistical methods to infer on the parameters in such dynamic models, particularly those defining epidemic spread, by combining prior information with experimental or observational data. Our proposal aims to explore the merits of the Bayesian Optimal Filtering technique in the estimation of the parameters of a stochastic SEIR (S = Susceptible, E = Exposed, I = Infectious, R = Removed) epidemic model. State Space Models (SSMs) are used to describe the epidemic dynamic. The unknown static parameters are estimated using a combination of Sequential Monte Carlo techniques with a Markov Chain Monte Carlo algorithm, . . . [less ▲]

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See detailHigh selfing rate, limited pollen dispersal and inbreeding depression in the emblematic African rain forest tree Baillonella toxisperma - Management implications
Duminil, Jérôme; Mendene Abessolo, D. T.; Ndiade Bourobou, D. et al

in Forest Ecology & Management (2016), 379

Mating system and gene flow are major influencing factors of species population dynamics and evolution. These factors are often not characterized in tropical tree species, yet they constitute basic ... [more ▼]

Mating system and gene flow are major influencing factors of species population dynamics and evolution. These factors are often not characterized in tropical tree species, yet they constitute basic information that must be considered to implement sustainable management practices. In particular, as logging implies a reduction of the density of congeneric mates, the connectivity through pollination between individuals has to be well characterized (selfing versus outcrossing rates, distances between mates). We conducted a genetic-based analysis (using 10 nuclear microsatellites) to determine the mating system and gene flow characteristics of an emblematic timber tree species from lowland rain forests of the Congo Basin, Baillonella toxisperma (Sapotaceae). The species, which is frequently exploited for its wood and for a number of non-timber forest products, naturally occurs at low densities (ca. 0.01–0.1 individuals/ha). It is supposedly an entomophilous species whose seeds are probably dispersed by mammals. We have shown that the species presents a mixed-mating system (about 20–40% of selfing depending on analysis method). However, the comparison of inbreeding parameters among cohorts suggests that inbred individuals die between seedling and mature tree stages. The mean pollen dispersal distance was relatively low for such a low-density population species (estimated to be 690 or 777 m depending on analysis method) and, together with a low mean number of pollen donors (NEP = 2.76), it suggests a pattern of nearest-neighbour mating where allo-pollen could be a limiting factor. However, B. toxisperma presents a relatively weak genetic structure (Sp statistic = 0.0095) indicative of long gene dispersal distance (rg = 3–5 km according to the assumed effective population density). Overall, this would indicate that gene flow occurs mainly by extensive seed dispersal in this species. These results suggest that mammals and local populations involved in the dispersal of the species play a key role by lowering biparental inbreeding effects. Sustainable population management might require assisted regeneration using unrelated planting material. [less ▲]

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See detailComputational modelling of local calcium ions release from calcium phosphate-based scaffolds
Manhas, Varun ULg; Guyot, Yann; Kerckhofs, Greet et al

in Biomechanics & Modeling in Mechanobiology (2016)

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See detailEvolution of biological innovations in early complex cells
Javaux, Emmanuelle ULg

Conference (2016, August)

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See detailInfluence of cracks on the stiffness of timber structural elements
Mergny, Elke ULg; Mateo, Raquel; Esteban, Miguel et al

Scientific conference (2016, August)

Cracks in timber structural elements lead users to downgrade them, while their influence on the mechanical properties is globally unknown. They are thus disadvantageous and responsible for an ... [more ▼]

Cracks in timber structural elements lead users to downgrade them, while their influence on the mechanical properties is globally unknown. They are thus disadvantageous and responsible for an underutilization of timber in new constructions. The phenomenon also impacts constructions subjected to transformation or renovation that are most of the time fully replaced, simply because of the ignorance of their bearing capacity. The present paper investigates the influence of cracks on stiffness, by analytical and numerical developments. It proposes a classification of cracks in six types (+ composite types) and models real beams, randomly cracked. It shows that the presence of cracks seems to decrease the stiffness of the beam. However, it is not so obvious to give the most damaging type of crack, among the six proposed. Further investigations will be necessary. [less ▲]

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See detailStatistically Bundled Shewhart Control Charts for Monitoring Delivery Chains Systems
Foster, Earnest; Faraz, Alireza ULg; Heuchenne, Cédric ULg

in European Journal of Industrial Engineering (2016)

Continuous monitoring of Delivery Time variables by means of control charts in a delivery chain is a very recent application of Statistical Process Control (SPC) to the service sector. The aim of the ... [more ▼]

Continuous monitoring of Delivery Time variables by means of control charts in a delivery chain is a very recent application of Statistical Process Control (SPC) to the service sector. The aim of the proposed method is to provide supply chain decision makers with an easy to be managed tool monitoring the current functioning state of the delivery chain. The implementation of SPC control charts makes it possible to limit over-corrections to false alarm conditions and to maintain at an acceptable level the safety stock, with a consequent reduction of the overall management costs of the delivery chain. An illustrative example shows the proposed control chart implementation in a real delivery chain. [less ▲]

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See detailA general methodology for optimal load management with distributed renewable energy generation and storage in residential housing
Georges, Emeline ULg; Braun, James; Lemort, Vincent ULg

in Journal of Building Performance Simulation [=JBPS] (2016)

In the US, buildings represent around 40% of the primary energy consumption and 74% of the electrical energy consumption [U.S. Department of Energy (DOE). 2012. 2011 Buildings Energy Data Book. Energy ... [more ▼]

In the US, buildings represent around 40% of the primary energy consumption and 74% of the electrical energy consumption [U.S. Department of Energy (DOE). 2012. 2011 Buildings Energy Data Book. Energy Efficiency & Renewable Energy]. Incentives to promote the installation of on-site renewable energy sources have emerged in different states, including net metering programmes. The fast spread of such distributed power generation represents additional challenges for the management of the electricity grid and has led to increased interest in smart control of building loads and demand response programmes. This paper presents a general methodology for assessing opportunities associated with optimal load management in response to evolving utility incentives for residential buildings that employ renewable energy sources and energy storage. An optimal control problem is formulated for manipulating thermostatically controlled domestic loads and energy storage in response to the availability of renewable energy generation and utility net metering incentives. The methodology is demonstrated for a typical American house built in the 1990s and equipped with a single-speed air-to-air heat pump, an electric water heater and photovoltaic (PV) collectors. The additional potential associated with utilizing electrical batteries is also considered. Load matching performance for on-site renewable energy generation is characterized in terms of percentage of the electricity production consumed on-site and the proportion of the demand covered. For the purpose of assessing potential, simulations were performed assuming perfect predictions of the electrical load profiles. The method also allows determination of the optimal size of PV systems for a given net metering programme. Results of the case study showed significant benefits associated with control optimization including an increase of load matching between 3% and 28%, with the improvement dependent on the net metering tariff and available storage capacity. The estimated cost savings for the consumer ranged from 6.4% to 27.5% compared to no optimization with a unitary buy-back ratio, depending on the available storage capacity. Related reduction in CO2 emissions were between 11% and 46%. Optimal load management of the home thermal systems allowed an increase in the optimal size of the PV system in the range of 13–21%. [less ▲]

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See detailPEGylation of lipoplexes: The right balance between cytotoxicity and siRNA effectiveness
Lechanteur, Anna ULg; Furst, Tania ULg; Evrard, Brigitte ULg et al

in European Journal of Pharmaceutical Sciences (2016), 93

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See detailLe traumatisme psychologique des anesthésistes suite aux erreurs humaines : Quand les processus de résilience organisationnelle renforcent la résilience individuelle
Blavier, Adelaïde ULg; Nyssen, Anne-Sophie ULg

Conference (2016, August)

Les erreurs médicales provoquent souvent des dommages énormes, pour la victime en premier lieu bien évidemment mais aussi pour le ou les professionnel(s) impliqué(s) dans l’erreur ainsi que pour les ... [more ▼]

Les erreurs médicales provoquent souvent des dommages énormes, pour la victime en premier lieu bien évidemment mais aussi pour le ou les professionnel(s) impliqué(s) dans l’erreur ainsi que pour les institutions hospitalières. L’objectif de cette communication est d’analyser le vécu post-erreur humaine chez des anesthésistes en étudiant l’impact de l’événement sur ces médecins. Nous avons récolté 217 incidents/accidents qui se sont produits en anesthésie en milieu hospitalier avec une analyse complète de l’événement, son origine et ses conséquences pour le patient et l’anesthésiste. Nos résultats montrent que les dommages à court terme pour le patient influencent significativement le sentiment de colère contre soi-même chez l’anesthésiste. Les dommages à long terme pour le patient provoquent de la colère contre soi-même, des troubles de l’appétit et de la perte de plaisir. Plus les dommages pour le patient sont graves, plus ils provoquent de troubles chez l’anesthésiste, particulièrement quand le patient décède suite à l’erreur. En outre, les anesthésistes développent plus de ruminations, de sentiments de culpabilité et de pensées intrusives quand l'accident était considéré comme évitable. Enfin, nous notons l’importance pour les anesthésistes de pouvoir parler de l’événement dans un cadre bienveillant avec pour effet de diminuer les reviviscences et ruminations personnelles, de faire taire les rumeurs, et d’améliorer la qualité des relations entre collègues. Ainsi la gestion institutionnelle des erreurs humaines dans une perspective constructive et bienveillante est génératrice de résilience en permettant aux médecins d’apprendre de leurs erreurs et d’améliorer leur expertise professionnelle au lieu de développer une psychopathologie posttraumatique [less ▲]

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See detailHeart Team Session
PIERARD, Luc ULg; LANCELLOTTI, Patrizio ULg; PETERMANS, Jean ULg et al

Conference (2016, August)

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See detailEntretien avec Céline Letawe - ULg
Letawe, Céline ULg

in Chambre Belge des Traducteurs et Interprètes (Ed.) Le Linguiste (2016)

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See detailImpact of vertical and horizontal advection on nutrient distribution in the southeast Pacific
Barceló-Llull, Barbara; Mason, Evan; Capet, Arthur ULg et al

in Ocean Science (2016), 12(4), 1003-1011

An innovative approach is used to analyze the impact of vertical velocities associated with quasi-geostrophic (QG) dynamics on the redistribution and uptake of nitrate in the southeast Pacific (SEP). A ... [more ▼]

An innovative approach is used to analyze the impact of vertical velocities associated with quasi-geostrophic (QG) dynamics on the redistribution and uptake of nitrate in the southeast Pacific (SEP). A total of 12 years of vertical and horizontal currents are derived from an observation based estimate of the ocean state. Horizontal velocities are obtained through the application of thermal wind balance to weekly temperature and salinity fields. Vertical velocities are estimated by integration of the QG omega equation. Seasonal variability of the synthetic vertical velocity and kinetic energy associated with the horizontal currents is coincident, with peaks in austral summer (November–December) in accord with published observations. The impact of vertical velocity on SEP nitrate uptake rates is assessed by using two Lagrangian particle tracking experiments that differ according to vertical forcing (ω = ωQG vs. ω = 0). From identical initial distributions of nitrate-tagged particles, the Lagrangian results show that vertical motions induce local increases in nitrate uptake reaching up to 30 %. Such increases occur in low uptake regions with high mesoscale activity. Despite being weaker than horizontal currents by a factor of up to 10−4, vertical velocity associated with mesoscale activity is demonstrated to make an important contribution to nitrate uptake, hence productivity, in low uptake regions. [less ▲]

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See detailConference on Exploring the stakeholders’ dynamics of “Smart City” projects: the case of Belgium
Desdemoustier, Jonathan ULg; Crutzen, Nathalie ULg

Scientific conference (2016, August)

This presentation proposes to explore the stakeholders’ dynamics in Belgium thanks to a multiple-case study. The research conducted is thus qualitative in nature: eleven “Smart City” projects were studied ... [more ▼]

This presentation proposes to explore the stakeholders’ dynamics in Belgium thanks to a multiple-case study. The research conducted is thus qualitative in nature: eleven “Smart City” projects were studied in Belgium. The goal is to highlight problematics inside the interplay and communication between stakeholders of Smart City projects and to furnish concrete practical recommendations for key stakeholders in smart city initiatives (local governments, multinational/local businesses, citizens, etc.). Even if the 11 projects are very different in their nature, the research proposes some keys scientific findings regarding stakeholders’ dynamics in this kind of projects. [less ▲]

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See detailThe future impacts on downstream communities: A case study of the multipurpose Nam Mang 3 hydropower Project in Lao PDR
Kouangpalath, Phimthong ULg; Lebailly, Philippe ULg; Ducourtieux, Olivier

in Sky Journal of Agricultural Research (2016), 5(6), 105-128

Considering future projects, this paper examines the effects of hydropower dam projects on downstream communities. This study was conducted in the multi-purpose hydropower and irrigated areas of the Nam ... [more ▼]

Considering future projects, this paper examines the effects of hydropower dam projects on downstream communities. This study was conducted in the multi-purpose hydropower and irrigated areas of the Nam Mang 3 hydropower. Using a survey study with various stakeholders, household survey, several interviews were held with key informants in addition to field work observation. It was determined that this project has caused a number of negative impacts on farmers, especially those in downstream areas, directly concerned water releases from dam and affecting the benefits from irrigation. The main findings show that farmers are able to grow a second season of rice crops, but the electricity generated in the rainy season from the dam leads to the rice fields flooding along the downstream areas. [less ▲]

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See detailRelease of cardiac biomarkers during a cycling race
LE GOFF, Caroline ULg; Kaux, Jean-François ULg; D'OTREPPE DE BOUVETTE, Stéphanie ULg et al

in World Journal of Cardiovascular Diseases (2016), 6(8), 285-294

Objectives: Over the past two decades, a large interest in cardiac marker elevations has developed in endurance sports events. The intense effort is not without risk. We aim to see if the relatively ... [more ▼]

Objectives: Over the past two decades, a large interest in cardiac marker elevations has developed in endurance sports events. The intense effort is not without risk. We aim to see if the relatively cardiospecific biomarkers could show the damage on cardiac muscle cells. Methods: Fourteen cyclists were recruited for an international race (177km). We studied the release of injury related cardiac markers, risk related cardiac markers, renal function markers and blood cytology. The subjects were submitted to three blood test: one before (T0), one just after (T1) and the last one 3 hours after the race (T3). Results: Blood cytology markers, namely erythrocytes, hemoglobin, hematocrit, and average hemoglobin concentration, were found to evolve in a similar way. Renal function markers, such as creatinin, cystatin C and uric acid, showed a post effort increase that might be related to renal blood flow depletion during exercise. Cardiac and muscular markers were all increased at T1. Conclusions: Physiological stress induced by an international cycling race certainly has consequences on cardiac muscle cells. Fortunately, those blood concentration variations are more representative of a transitional state, due to an imbalance created by an intense aerobic effort maintained during several hours, rather than an irreversible injury. [less ▲]

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See detailPhonological acquisition in CLIL- and non-CLIL education
Rasier, Laurent ULg

Conference (2016, August)

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See detailDu côté de chez...Godefroid Kurth. Réflexions personnelles
Genin, Vincent ULg

in Bulletin Trimestriel de l'Institut Archéologique du Luxembourg Arlon (2016), 92(3/4), 99-107

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See detailMicroorganisms and semiochemicals to manipulate aphidophagous predators
Verheggen, François ULg

Conference (2016, August)

Semiochemicals provide a powerful way for organisms to communicate and coordinate their behaviors. But they also represent opportunities for other organisms to intercept and exploit such signals. There ... [more ▼]

Semiochemicals provide a powerful way for organisms to communicate and coordinate their behaviors. But they also represent opportunities for other organisms to intercept and exploit such signals. There are now numerous examples of natural enemies eavesdropping the intraspecific communication of their prey to better locate them. Aphid natural enemies, including predators and parasitoids, frequently exhibit innate responses to chemical cues reliably associated with aphids, and there is also abundant evidence that learning of profitable chemical cues frequently occurs. Thenceforth, the efficiency of aphid natural enemies to locate their prey is mainly based on their ability to perceive and orientate toward aphid-associated semiochemicals. Aphid predators were shown to respond to different groups of aphid-related semiochemicals, including aphid-induced plant volatiles; aphid pheromones and the more recently identified bacteria-produced honeydew volatiles. These laboratory studies suggest potentially promising avenues for the deployment of aphid-associated semiochemicals for the management of these pest species. While laboratory experiments are invaluable tools for revealing mechanisms, additional field studies are however needed to test ecological relevance of the observed effects. Although it is now possible to attract naturally occurring aphid predators in a crop field using semiochemicals, future work should more fully explore the broader ecological context in which signaling occurs. The information gained from a deeper understanding of the chemical ecology of aphid-natural enemy interaction will enhance our understanding of the chemical biology and ecology of aphids, and may facilitate the design of novel control strategies. [less ▲]

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See detailNdBaScO4 : aristotype of a new family of geometric ferroelectrics?
Cochrane, Amber K.; Telfer, Michael; Dixon, Charlotte A. L. et al

in Chemical Communications (2016), 52

NdBaScO4 represents the aristotype structure of a new series of <110>-cut layered perovskites; it is suggested that compositional fine-tuning is likely to produce a family of new geometric ferro ... [more ▼]

NdBaScO4 represents the aristotype structure of a new series of <110>-cut layered perovskites; it is suggested that compositional fine-tuning is likely to produce a family of new geometric ferro- electrics, driven primarily by octahedral tilting. [less ▲]

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See detailLa légation des Pays-Bas en cour de Rome au temps de l’agent Laurent du Blioul (1573-1598): Une légation au cœur des réseaux de la monarchie de Philippe II
Regibeau, Julien ULg

in Actes du neuvième congrès de l'Association des Cercles francophones d'Histoire et d'Archéologie de Belgique (2016, August)

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