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See detailVibrio spp chez l’Homme - Vibrio spp bij de mens
MELIN, Pierrette ULg; SACHELI, Rosalie ULg

in POLET, Marie (Ed.) Vibrio spp dans l’alimentation et chez l’Homme - Formation (2016, December 15)

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See detailA step-by-step recipe of band-spli3ng technique for isola8on of ionospheric signal in L-band InSAR data
Furuya, Masato; Suzuki, Takato; De Rauw, Dominique ULg

Poster (2016, December 15)

Ionospheric signals are widely regarded as nuisance in low- frequency InSAR data, and thus a variety of correction techniques have been proposed. Although band-splitng of range spectrum has been shown to ... [more ▼]

Ionospheric signals are widely regarded as nuisance in low- frequency InSAR data, and thus a variety of correction techniques have been proposed. Although band-splitng of range spectrum has been shown to be effectve (Brcic et al., 2010; Rosen et al., 2010; Gomba et al., 2015), the band- spliting technique seems to have not been widely used. Whereas this would be partly because the impacts of ionosphere on InSAR data are not necessarily serious, we consider that this could be also because the details of the technique have not been reproducibly shown. Here we show our step-by-step recipe of the band-spliting technique, and demonstrate two case studies that reveal the effectiveness of the technique. [less ▲]

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See detailIdentifying stone tool hafting in the archaeological record: interpretative potential and methodology
Rots, Veerle ULg

Scientific conference (2016, December 15)

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See detailThe influence of spatially structured soil properties on tree community assemblages at a landscape scale in the tropical forests of southern Cameroon
Vleminckx, Jason; Doucet, Jean-Louis ULg; Morin, Julie ULg et al

in Journal of Ecology (2016)

Species distribution within plant communities results from both the influence of deterministic processes, related to environmental conditions, and neutral processes related to dispersal limitation and ... [more ▼]

Species distribution within plant communities results from both the influence of deterministic processes, related to environmental conditions, and neutral processes related to dispersal limitation and stochastic events, the relative importance of each factor depending on the observation scale. Assessing the relative contribution of environment necessitates controlling for spatial dependences among data points. Recent methods, combining multiple regression and Moran's eigenvectors maps (MEM), have been proved successful in disentangling the influence of pure spatial processes related to dispersal limitation, pure environmental variables (not spatially structured) and spatially structured environmental properties. However, the latter influence is usually not testable when using advanced spatial models like MEM. To overcome this issue, we propose an original approach, based on torus-translations and Moran spectral randomizations, to test the fraction of species abundance variation that is jointly explained by space and seven soil variables, using three environmental and tree species abundance data sets (consisting of 120, 52 and 34 plots of 0·2 ha each, located along 101-, 66- and 35-km-long transect-like inventories, respectively) collected in tropical moist forests in southern Cameroon. The overall abundance of species represented by ≥30 individuals, and 27% of these species taken individually, were significantly explained by fine-scale (<5 km) and/or broad-scale (5–100 km) spatially structured variations in soil nutrient concentrations (essentially the concentration of available Mn, Mg and Ca) along the 120-plots area. The number of significant tests considerably decreased when investigating the two smaller data sets, which mostly resulted from low statistical power rather than weaker floristic and/or edaphic variation captured among plots. Synthesis. Our results provide evidence that tree species turnovers are partly controlled by spatially structured concentrations in soil nutrients at scales ranging from few hundreds of metres to c. 100 km, a poorly documented subject in Central African forests. We also highlight the usefulness of our testing procedure to correctly interpret the space-soil fraction of variation partitioning analyses (which always accounted here for the most important part of the soil contribution), as this fraction was sometimes relatively high (R2 values up to c. 0·3) but nearly or not significant. [less ▲]

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See detailBIM état de la situation
Boutemadja, Abdelkader ULg

Conference (2016, December 15)

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See detail11 interventions dans la presse écrite et radio au sujet des techno-pédagogies, du 22 mai 2013 jusqu'au 16 janvier 2017
Verpoorten, Dominique ULg

Article for general public (2016)

Ces interventions témoignent du suivi appréciatif et critique des initiatives en matière de techno-pédagogie pour l'enseignement supérieur.

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See detailMetal Carbodiimides and Metal Cyanamides as Electrode Materials
sougrati, Moulay tahar; Darwiche, Ali; Monconduit, Laure et al

Patent (2016)

(EN)The invention relates to the use of a metal carbodiimide or a metal cyanamide as a new active material for a negative electrode, a negative electrode comprising said metal carbodiimide or metal ... [more ▼]

(EN)The invention relates to the use of a metal carbodiimide or a metal cyanamide as a new active material for a negative electrode, a negative electrode comprising said metal carbodiimide or metal cyanamide, its preparation method, a battery comprising said negative electrode, and a method for the preparation of a composite material. (FR)L'invention concerne l'utilisation d'un carbodiimide métallique ou d'un cyanamide métallique en tant que nouveau matériau actif pour une électrode négative, une électrode négative comprenant ce carbodiimide métallique ou ce cyanamide métallique, son procédé de préparation, une batterie comprenant l'électrode négative, et un procédé pour la préparation d'un matériau composite. [less ▲]

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See detailPréface à l'ouvrage d'Alain Coenen "Les services publics locaux au coeur de l'effervescence sociétale"
Behrendt, Christian ULg

in Coenen, Alain (Ed.) Les services publics locaux au coeur de l'effervescence sociétale (2016)

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See detailIntegrating Non-Collocated Well and Geophysical Data to Capture Lithological Heterogeneity at a Managed Aquifer Recharge and Recovery Site
Gottschalk, Ian; Hermans, Thomas ULg; Caers, Jef et al

Poster (2016, December 15)

Aquifer recharge and recovery (ARR) is the process of enhancing natural groundwater resources and recovering water for later use by constructing engineered conveyances. Insufficient understanding of ... [more ▼]

Aquifer recharge and recovery (ARR) is the process of enhancing natural groundwater resources and recovering water for later use by constructing engineered conveyances. Insufficient understanding of lithological heterogeneity at ARR sites often hinders attempts to predict where and how quickly infiltrating water will flow in the subsurface, which can adversely affect the quality and quantity of available water in the ARR site. In this study, we explored the use of electrical resistivity tomography (ERT) to assist in characterizing lithological heterogeneity at an ARR site, so as to incorporate it into a flow and contaminant transport model. In this case, we had non-collocated well core log data and ERT data from a full-scale ARR basin. We compared three independent methods for producing conditional lithology-resistivity probability distributions: 1) a search template to relate the nearest logged well lithologies with ERT resistivity panels, given search criteria; 2) a maximum likelihood estimation (MLE) to match bimodal normal distributions to the histogram of each ERT line; and 3) variogram-based lithology indicator simulations constrained to well data. Each approach leverages Bayes’ Rule to estimate lithology probability given electrical resistivity. The simplest approach (method 1) yields an erroneous conditional probability function where sand dominates the conditional probability at nearly all resistivities, due in part to the strong presence of sand in the wells nearest the ERT lines. The approaches using MLE and lithology simulations (methods 2 and 3) produce similar, more realistic lithofacies probability functions. The range of resistivities where clay and sand overlap differs between methods 2 and 3: ranging between 100 and 200 ohm-m for method 2, and between 30 and 50 ohm-m for the method 3. These differences affect the posterior lithology distributions in multiple point geostatistical (MPS) simulations, and in turn, predictions of flow from models which integrate these results. To test the models, we can compare measured breakthrough times of recharged water at the site to groundwater flow simulation results using the lithofacies models created by each method. The methods described here can inform the integration of non-collocated geophysical data into a variety of applications. [less ▲]

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See detailIntroduction à la perspective en première personne : le cas de l’anorexie
Englebert, Jérôme ULg

Conference (2016, December 15)

La distinction des perspectives en première et troisième personnes est un apport récent et décisif de la phénoménologie à la psychopathologie (Parnas, Sass & Zahavi, 2012). La perspective en troisième ... [more ▼]

La distinction des perspectives en première et troisième personnes est un apport récent et décisif de la phénoménologie à la psychopathologie (Parnas, Sass & Zahavi, 2012). La perspective en troisième personne, campée par les dernières versions du DSM ou par l’evidence based medicine, consiste en l’attribution depuis une position externe de signes cliniques repérés indépendamment du ressenti exprimé par le patient. L’exemple typique de ces signes est le délire et l’hallucination du schizophrène. Ces symptômes cristallisent les difficultés qu’éprouve le sujet à se reconnaitre affecté du trouble (l’anosognosie), et ce point est considéré par les modèles dominants comme une cible thérapeutique prioritaire. La visée de ces techniques, orthopédiques et psycho-éducatives, est que le patient parvienne à « reconnaitre » sa maladie. Selon cette perspective en troisième personne, il est attendu qu’il adopte, intègre la position propre à son évaluateur, et externe à sa subjectivité intrinsèque. La démarche opposée, celle de la prise en considération d’une perspective en première personne, interroge, considère et concentre son attention sur l’expérience subjective exprimée par le patient. Si l’on reprend l’exemple princeps de la schizophrénie, ce sont la « perte de l’évidence naturelle » des choses, un « trouble du sens commun » ou un « sentiment de diminution du soi » que verbalisent les patients. Ces signes cliniques, révélant l’expérience du soi, deviennent l’élément psychopathologique structurant et mettent en évidence une manière d’être-au-monde, ici schizophrénique. Le pari de cette journée d’étude consacrée à l’anorexie est de chercher à appliquer ce passage vers une perspective compréhensive en première personne pour les sujets affectés de ce trouble. Des travaux pionniers en la matière, bien que ne se réclamant pas de la phénoménologie, sont certainement ceux du psychiatre éthologue liégeois Albert Demaret (1979). Celui-ci, suggère, de façon quelque peu déconcertante, de ne plus focaliser l’attention prioritairement sur l’aspect purement médical relatif à la perte de poids et au refus alimentaire. Le comportement qui retient particulièrement son attention est l’altruisme (souvent alimentaire), qu’il considère comme « la composante la plus fondamentale du syndrome » (p. 152). Outre le fait de révéler les composantes adaptatives du trouble, son étonnant modèle permet d’entrer en consonance avec le discours des patients anorexiques qui, bien souvent, ne perçoivent pas leur minceur (mécanisme de déni) ou expriment que leur problématique ne se situe pas, selon eux, dans leur sous-alimentation. L’anosognosie anorexique et cet effroyable tendance à se priver d’alimentation au risque de mettre sa vie en danger, si l’on ouvre la porte à la perspective en première personne – si on laisse la parole au sujet –, laissent la place à un besoin (dont l’excessivité peut être reconnue) de s’occuper des autres, de les nourrir, mais aussi une hyper-attention au regard qu’on leur porte. L’investissement émotionnel et corporel des relations est souvent présenté comme étant insatisfaisant, voire comme étant l’élément moteur de leur mal-être. Ce pas de côté de la vision omnisciente du médical, assumant une remise en cause du pouvoir de domination qu’entraine la perspective en troisième personne, se révèle être un outil psychothérapeutique tout à fait pertinent. Il désacralise le problème de l’anosognosie, remet en cause le déni (ce mécanisme devient également celui de l’entourage de l’anorexique qui ne peut percevoir le surinvestissement altruiste), et ouvre la voie à une perspective intersubjective, co-construite. Cette journée d’étude a pour ambition de mettre en lumière cette préoccupation pour l’éprouvé anorexique, évoquer les modes de communication de ces patients et laisser place au discours qu’ils ont souvent du mal à livrer. Il se révèle que les apports de disciplines comme la philosophie ou l’anthropologie, ainsi que ceux de la pratique clinique sont des détours essentiels à ce programme d’étude. Nous discuterons également du symptôme anorexique lorsqu’il est secondaire à un psychotraumatisme (quelle place cette tendance à la restriction vient combler dans l’expérience de vie du sujet traumatisé). Cette journée est ouverte tant aux praticiens de terrain et personnes intéressées par les matières cliniques qu’aux chercheurs universitaires en sciences humaines. [less ▲]

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See detailThe complex behavior of the satellite footprints at Jupiter: the result of universal processes?
Bonfond, Bertrand ULg; Grodent, Denis ULg; Badman, Sarah V. et al

Poster (2016, December 14)

At Jupiter, some auroral emissions are directly related to the electromagnetic interaction between the moons Io, Europa and Ganymede on one hand and the rapidly rotating magnetospheric plasma on the other ... [more ▼]

At Jupiter, some auroral emissions are directly related to the electromagnetic interaction between the moons Io, Europa and Ganymede on one hand and the rapidly rotating magnetospheric plasma on the other hand. Out of the three, the Io footprint is the brightest and the most studied. Present in each hemisphere, it is made of at least three different spots and an extended trailing tail. The variability of the brightness of the spots as well as their relative location has been tentatively explained with a combination of Alfvén waves’ partial reflections on density gradients and bi-directional electron acceleration at high latitude. Should this scenario be correct, then the other footprints should also show the same behavior. Here we show that all footprints are, at least occasionally, made of several spots and they all display a tail. We also show that these spots share many characteristics with those of the Io footprint (i.e. some significant variability on timescales of 2-3 minutes). Additionally, we present some Monte-Carlo simulations indicating that the tails are also due to Alfvén waves electron acceleration rather than quasi-static electron acceleration. Even if some details still need clarification, these observations strengthen the scenario proposed for the Io footprint and thus indicate that these processes are universal. In addition, we will present some early results from Juno-UVS concerning the location and morphology of the footprints during the first low-altitude observations of the polar aurorae. These observations, carried out in previously unexplored longitude ranges, should either confirm or contradict our understanding of the footprints. [less ▲]

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See detailPsychologie clinique et suicide
Englebert, Jérôme ULg

Scientific conference (2016, December 14)

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See detailHow tree architecture varies across coexisting tropical tree species and relate to ecological strategies?
Loubota Panzou, Grâce Jopaul ULg; Ligot, Gauthier ULg; Loumeto, Jean-Joël et al

Conference (2016, December 14)

Architecture refers to the overall shape of a tree and the spatial position of its components. Tree height determines the position in the forest canopy and access to light, while the amount and spatial ... [more ▼]

Architecture refers to the overall shape of a tree and the spatial position of its components. Tree height determines the position in the forest canopy and access to light, while the amount and spatial distribution of the foliage depend on the depth and the width of the crown. The aim of this study is to understand how tree architecture varies across coexisting tropical tree species and relates to ecological strategies. Forty five coexisting tree species were sampled in the semi-deciduous forests of Northern Congo. Species were classified according to ecological strategies, specifically regeneration guilds: shade bearers (27 species), non-pioneers light demanding (14 species) and pioneers (4 species). For each species, 14–72 trees (968 trees in total) were measured over a large range of diameter (10–162 cm). At the tree level, we measured the diameter (D in cm), height (H in m), crown radius (Cr in m) and crown depth (Cd in m) and crown exposure index (CEI) was visually estimated. At species level, architectural traits were estimated at juvenile tree with diameter of 10 cm (H10, Cr10 and Cd10) and at adult stature with maximum diameter (Hmax, Crmax and Cdmax), life history traits (dispersal mode, phenology and regeneration guild) and functional traits (wood density and light requirement) were obtained. Our results showed a significant variation in tree allometry between coexisting species. The interspecific variation was related to light requirement (H-D allometry), dispersal mode (Cr-D allometry) and liana infestation (Cd-D allometry). Large-statured tree species were light demanding, deciduous and wind dispersed, while small-statured tree species were evergreen, dense wooded, and animal dispersed. Architectural traits strongly differed between regeneration guilds. [less ▲]

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See detailDEVELOPMENT OF A DISCRETE EVENT SIMULATION BASED TOOL FOR OFFSHORE LOGISTICS IN WIND FARM INSTALLATION
Muhabie, Yohannes Tekle ULg

Doctoral thesis (2016)

The o shore wind energy development has shown a progress in the last ten years. Distance from the coast and the depth of the water are increasing continuously. The transport and installation of o -shore ... [more ▼]

The o shore wind energy development has shown a progress in the last ten years. Distance from the coast and the depth of the water are increasing continuously. The transport and installation of o -shore wind turbines is highly dependent on weather condition at sea. Delaying an activity in the logistics chain could have a signi cant impact on overall project completion. Hence there is a need to have a well-organized and thoroughly analyzed planning of the overall processes starting from the producers sites until the o shore site where the turbines will be installed. The weather conditions and the installation strategies are the major limit factors in uencing the o shore wind farm installations. In this thesis a Discrete Event Simulation (DES) based tool has been developed for o shore logistics in wind farm installation. It takes into account the weather restriction limits (wind speed and wave height), distance matrix, vessel characteristics and installation strategies. The logistics model maps out the activities of the o shore wind farm installations. Both historical and probabilistic weather data approaches have been implemented, analyzed and compared. The results indicated that the probabilistic approach is highly a ected by the random seed numbers used to set up the stochastic behavior of the input variable. Application of the developed tools to real O shore Wind Farm (OWF) con guration illustrated that there is a good agreement between the results obtained from the two approaches. However, it has been identi ed that the probabilistic approach may slightly underestimate the project lead time compared to the results obtained using historical data. Furthermore, weather downtime and sensitivity analysis have been carried out for di erent weather scenarios in order to identify the parameters that a ect the logistic chain signi cantly during the o shore wind farm installation. In this context, it is indicated that the lifting operation (limited by wind speed) causes the highest down time compared to other activities and improving the lifting operations could result in a signi cant reduction (10-15 %) in the overall project completion time. In conclusion, overall analysis indicated that the application of a DES tool improves the decision support system including the planning and control of the logistics processes of the o shore wind farm installation, reducing the associated risks. [less ▲]

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Peer Reviewed
See detailElectrical Resistivity Monitoring of Heat Tracer to Characterize Lab-Scale Hydraulic Conductivity Distributions
Adetokunbo, Peter; Hermans, Thomas ULg; Oware, Erasmus

Poster (2016, December 14)

Knowledge of the spatial variations of hydraulic conductivity (K) is crucial to almost every hydrogeological investigation. The representative scale of K estimates from traditional slug and pumping tests ... [more ▼]

Knowledge of the spatial variations of hydraulic conductivity (K) is crucial to almost every hydrogeological investigation. The representative scale of K estimates from traditional slug and pumping tests are, however, inadequate to accurately predict hydrogeological processes. There is increasing interest in the application of electrical resistivity tomography (ERT) to quantify spatially continuous K variations. ERT estimation of high-resolution K distributions, however, requires continuous injection of saline tracer (ST) into an aquifer over an extended period, which is feasible but impractical. Here, we present electrical resistivity thermography (ERTh) to evaluate the potential application of time-lapse ER monitoring of heat tracer (HT) to characterize high-resolution K architectures. Unlike ST, long term HT experiments are comparatively easier to manage and repeatable with minimal environmental impact. We estimate K variations via petrophysical coupling of flow and heat transport with joint time-lapse ER and discrete multi-level temperature breakthrough curves. We illustrate the strategy with a 2-D lab-scale sandbox experiment. To construct the heterogeneous field, three lenses with high-K properties with each consisting of gravel, coarse sand, and a mixture of coarse and fine sand, were created within a background of comparatively low-K fine sand. The experiment involved continuous injection and extraction of heat, respectively, at the left and right boundaries of the lab-scale aquifer. We simultaneously performed time lapse ER monitoring of the heat transport and temperature measurements at four discrete multi-levels near the heat extraction well. Results of the coupled inversions demonstrate that ER monitoring of heat tracer provides a unique opportunity to characterize high-resolution spatially continuous K variations, which seems more practical for field applications in contrast to that of the traditional ST. [less ▲]

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See detailValorisation des variétés de dattes secondaires tunisiennes par l’application de traitement hydrothermique
Mrabet, Abdessalem ULg

Doctoral thesis (2016)

The fruit of the date palm (Phoenix dactylifera L.) is one of the most abundant fruits in the world. Nearly 2,000 cultivars of date palm are known, but only some of them are evaluated for their ... [more ▼]

The fruit of the date palm (Phoenix dactylifera L.) is one of the most abundant fruits in the world. Nearly 2,000 cultivars of date palm are known, but only some of them are evaluated for their performance and their fruit quality. This work is a contribution to give value addition to date palm fruit (flesh and seed), from Tunisian secondary varieties, by studying physico-chemical and techno-functional properties of their heir solid fraction rich in fiber and their fraction liquid and rich in phenol and sugar, obtained after pretreatment. Date fleshes contained essentially 60 % total carbohydrates, 23-27 % lignin and 5-4 % dietary fibers. The rest of the components were lower than 4%, with remarkably low amounts of fat (0.3-0.5%) and phenols (0.04-0.07%). In contrast, the percentage of fat (13-17%) and phenols (1-5%) present in date seeds were of great interest. Due to these amounts of phenols, the antiradical activity of seeds was much higher (131-400 mmol TE/Kg dry weight) than that of the flesh (32-47 mmol TE/Kg dry weight). A pretreatment was tested for the total utilization of these dates. After applying several steam treatments condition, valuable dietary fiber concentrates have been obtained. Their recoveries were very similar for the different assays. Only its granulometry showed differences, increasing the fraction with size lower than 4 mm in more intense treatments. DFC had also a good nutritional quality, with high phenol (4-8%), cellulose (12-20%), hemicellulose (5-22%), protein (9-14%), fat (5-11%) and lignin (44-71%). Treatment conditions had higher influence than date variety in the chemical composition. Study of functional properties of these DFC revealed good water and oil retention capacities (5,37-8.50 g water/g DFC and 7,03-8.74 g oil/g DFC, respectively). Furthermore, DFC had also very high antiradical activity (230-580 mmols Trolox/ Kg FC). Thus, these DFC could be considered as a valuable source of antioxidant dietary fiber. The study of physicochemical characteristics showed that DFC had the highest potential to be used as a food ingredient. As an application, the DFC were incorporated in muffin formulations at levels of 2,5 and 5 %. The addition of DFC slightly influenced the technological characteristics of dough and increased their antioxidant properties compared to control. Study of sensory characteristics revealed that there are no significant differences between control and the muffin with DFC. The only concern about the use of this DFC is that its ratio between insoluble and soluble fiber (IF/SF) is very high, around 19, but the best physiological effects are obtained with ratios 1-2.3. For this reason an enzymatic digestion has been assayed in order to decrease this ratio. The different results have shown that, the amount of SF increased from 1.8% to 6.3%, and the ratio IF/SF changed from 19 to 2-3. Moreover, in addition to an increase in the antiradical activity the SF, gluco-, manno-, and xylo-oligosaccharides were identified, oligosaccharides which has been postulated as prebiotics. The study of the liquid phase, rich in soluble antioxidant (phenols), and sugars, was also necessary for the total utilization of the thermally treated dates. The obtained liquid fractions were characterized and their antioxidant capacity determined. The concentration of total phenols increased, by treatments up to 5311 mg/kg of fresh dates, and their antioxidant activity up to 62.5 mmol Trolox/kg of fresh date. Different phenolic extracts have been obtained from the liquid phase in order to used as a antioxidant in food or nutraceutical formulation. The date phenolic extract were fractionated chromatographically using adsorbent or ionic resins to determine the most active fractions. The phenolic profiles were determined for each fraction, yielding fractions with interesting antioxidant activities with EC50 values of up to 0.08 mg/L or values of TEAC of 0.67 mmol Trolox®/g of extract. In addition, the antioxidant properties on lipophilic matrix of the organic extracts of date were also determined, using vegetable and fish oils, as well as the antimicrobial activity. The result showed a remarkable protection against lipid oxidation in oils, increasing the stability of sunflower oil by Rancimat method by four-fold. In addition, some extracts with interesting antimicrobial effects. [less ▲]

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