References of "Scientific congresses and symposiums"
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See detailControlled DCD donation is part of the solution to liver graft shortage, regardless of donor age
DETRY, Olivier ULg; MEURISSE, Nicolas ULg; DELWAIDE, Jean ULg et al

in Acta Gastro-Enterologica Belgica (2014, March), 77(1), 16

Aim: Results of donation after circulatory death (DCD) liver transplantation (LT) are impaired by ischemic bile duct lesions caused by procurement warm ischemia. Donor age is a risk factor in deceased ... [more ▼]

Aim: Results of donation after circulatory death (DCD) liver transplantation (LT) are impaired by ischemic bile duct lesions caused by procurement warm ischemia. Donor age is a risk factor in deceased donor LT, and particularly in DCD-LT. At the authors institute, age is not an absolute exclusion criterion to discard DCD liver grafts, controlled DCD donors receive comfort therapy before withdrawal, and cold ischemia is minimized. The aim of the present study was to report on the results of the first 10 years of this experience, and particularly on graft survival and the rate of post-transplant biliary complications, according to DCD donor age. 
 Methods: The authors retrospectively studied a consecutive series of 70 DCD-LT performed from 2003 to 2012, with at least one year of follow-up. This series was divided according to donor’s age, including 32 liver grafts from donors <55years, 20 between 56 and 69 years, and 18 from older donors >69 years. The three groups were compared in terms of donor and recipient demographics, procurement and transplantation conditions, peak laboratory values during the first post-transplant 72 hours, and results at one and four years. Median follow-up was 43 months. 
 Results: Overall graft survival was 98.5%, 91.4% and 69.5% at 1 month, 1 year and 4 years, respectively, without graft loss secondary to ischemic bile duct lesions. Cancer was the primary cause of graft loss and patient death. No difference other than age was noted between the three groups in donor and recipient characteristics, and in procurement conditions. There was no primary non-function but one patient needed re-transplantation for artery thrombosis. Biliary complications occurred similarly in the three groups. Graft and patient survival rates were not different at one and four years between the three groups. During the study period, there was an increasing liver procurement and transplantation activity, and in 2012, 30% of performed LT were DCD-LT, allowing a mean LT waiting time of 66 days. 
 Conclusions: This study shows comparable results between controlled DCD-LT from younger and older donors. Donor age >50 years should not be a contraindication to DCD-LT if other donor risk factors (such as warm and cold ischemia time) are minimized. DCD-LT with short cold ischemia may provide a significant source of liver grafts, decreasing waiting time. [less ▲]

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See detailA propos du retard de croissance intra-utérin
Saliba, Mariane ULg; Bourcy, Emilie ULg; Lapotre, Thibaut ULg et al

Poster (2014, March)

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See detailSnow cover and short-term synoptic events drive biogeochemical dynamics in winter Weddell Sea pack ice (AWECS cruise - June to August 2013)
Tison, J.-L.; Delille, Bruno ULg; Dieckmann, G. et al

Conference (2014, March)

This paper presents the preliminary results of an integrated multidisciplinary study of pack ice biogeochemistry in the Weddell Sea during the winter 2013 (June-August). The sea ice biogeochemistry group ... [more ▼]

This paper presents the preliminary results of an integrated multidisciplinary study of pack ice biogeochemistry in the Weddell Sea during the winter 2013 (June-August). The sea ice biogeochemistry group was one of the components of the AWECS (Antarctic Winter Ecosystem and Climate Study) cruise (Polarstern ANTXXIX-6). A total of 12 stations were carried out by the sea ice biogeochemistry group, which collected a suite of variables in the fields of physics, inorganic chemistry, gas content and composition, microbiology, biogeochemistry, trace metals and the carbonate system in order to give the best possible description of the sea ice cover and its interactions at interfaces. Samples were collected in the atmosphere above (gas fluxes), in the snow cover, in the bulk ice (ice cores), in the brines (sackholes) and in the sea water below (0m, 1m, 30 m). Here we present the results of basic physico-chemical (T°, bulk ice salinity, brine volumes, brine salinity, Rayleigh numbers) and biological (Chla) measurements in order to give an overview of the general status of the Weddell Sea winter pack ice encountered, and discuss how it controls climate relevant biogeochemical processes. Our results from the first set of 9 stations, mainly sampled along the Greenwich meridian and the easternmost part of the Weddell Sea definitively refute the view of a biogeochemically “frozen” sea ice during the Winter. This has already been demonstrated for the Spring and Summer, but we now see that sea ice sustains considerable biological stocks and activities throughout the Winter, despite the reduced amount of available PAR radiation. Accretion of the snow cover appears to play an essential role in driving biogeochemical activity, through warming from insulation, thus favouring brine transport, be it through potential convection, surface brine migration (brine tubes) or flooding. This results in a “widening” of the internal autumn layer (quite frequent in this rafting-dominated sea ice cover) and increase of the chla burden with age. Results from the second set of 3 stations in the western branch of the Weddell Sea gyre confirm that it comprises a mixture of older fast/second year ice floes with younger first-year ice floes. The older ice had the highest Chla concentrations of the entire cruise (>200 mgl-1), in an internal community enclosed within desalinized impermeable upper and lower layers. The first-year ice differs from that in the eastern Weddell Sea as it is dominated by columnar ice and (weak) algal communities are only found on the bottom or near the surface (no internal maximum). [less ▲]

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See detailUsing stable isotopes to unravel the role of sea-ice in the methane cycle
Sapart, C.J.; Zhou, Jiayun ULg; Niemann, T et al

Poster (2014, March)

Methane (CH4) plays an important role in the Earth’s climate system. The atmospheric CH4 concentration has increased in concert with the industrialization, but since the mid 80’s the CH4 growth rate ... [more ▼]

Methane (CH4) plays an important role in the Earth’s climate system. The atmospheric CH4 concentration has increased in concert with the industrialization, but since the mid 80’s the CH4 growth rate decreased to reach a near-zero level in 2000 and started to increase again from 2007 on. However, the underlying variations in sources and/or sinks that cause these variations are to date not well understood. To predict future climate, it is essential to unravel the processes controlling the CH4 cycle, especially in the Arctic regions, which are highly vulnerable to climate change and contain large CH4 reservoirs. Recently, an unexpected CH4 excess has been reported above Arctic sea-ice showing that sea-ice might play a significant role in the CH4 cycle. Nonetheless, the nature of the process leading to CH4 production in or nearby sea-ice has not yet been identified. We applied a new multi-proxy approach merging atmospheric chemistry, glaciology and biogeochemistry to understand and quantify the processes responsible for the CH4 excess above sea-ice. We performed CH4 isotope (13C and D) analyses on sea-ice samples, as well as microbial (lipid biomarkers) and geochemical measurements, to determine the possible pathways involved in CH4 production and removal in or nearby sea-ice. We will present results from sea-ice samples drilled above the shallow-shelf in Barrow (Alaska) from January to June 2009 as well as above deep Southern Ocean locations in 2013. Those results allow investigating the seasonality and spatial variability in methane formation and removal pathways associated to the methane enclosed in sea-ice. [less ▲]

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See detailDe rol van de bibliotheek in tijden van information overload
Decoster, Sara ULg

in Cahiers de la Documentation = Bladen voor Documentatie (2014, March), 68(1),

Cet article étudie le rôle que peut jouer la bibliothèque en temps d’information overload et part des deux composantes de base du phénomène de l’infobésité : en premier lieu, un flot de données ... [more ▼]

Cet article étudie le rôle que peut jouer la bibliothèque en temps d’information overload et part des deux composantes de base du phénomène de l’infobésité : en premier lieu, un flot de données objectivement important, et, en second lieu, la manière dont ces données sont traitées par le sujet humain, l’usager. Pour gérer l’afflux de données constant, la bibliothèque offre d’abord un outillage technique. Le développement récent des outils « discovery » peut être resitué dans cette veine. Deuxièmement, c’est en investissant dans les compétences informationnelles des utilisateurs que la bibliothèque peut lutter contre le versant subjectif de l’infobésité. Dans ce processus, la communication joue un rôle primordial. [less ▲]

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See detailTGF-B induced protein IG-H3 is essential for the growth of human liver metastases
Castronovo, Vincenzo ULg; Blomme, Arnaud; Delvenne, Philippe ULg et al

in Acta Gastro-Enterologica Belgica (2014, March), 77(1), 05

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See detailCertificat d’université en tutorat à distance : une approche de formation isomorphique pour acquérir des compétences de e-tuteur
Denis, Brigitte ULg

in Tutorales (2014, March), 12

Depuis plus d'une dizaine d'années, de nombreux auteurs ont décrit les rôles des tuteurs dans les dispositifs de formation en ligne (Depover et al, 2011 ; Salmon, 2000). La "présence" et les interventions ... [more ▼]

Depuis plus d'une dizaine d'années, de nombreux auteurs ont décrit les rôles des tuteurs dans les dispositifs de formation en ligne (Depover et al, 2011 ; Salmon, 2000). La "présence" et les interventions de ces derniers s'avèrent un facteur important dans l'efficacité de tels dispositifs, qu'il s'agisse de maintien de la motivation des apprenants ou du processus d'apprentissage. La variété des méthodologies mises en œuvre dans les scénarios de formation (apprentissage collaboratif, coopératif, individuel...) entraînent des modalités d'interaction différentes entre e-tuteur et apprenants. Se basant sur les étapes de formation au e-tutorat décrites par Denis (2003), un processus original de formation de e-tuteurs est proposé afin de rencontrer la diversité et l'adéquation des profils à adopter selon le contexte considéré. Le scénario de formation au e-tutorat recourt au principe d'isomorphisme en pédagogie (Leclercq, 1998). Outre des apports théoriques relatifs à la problématique traitée et une approche réflexive sur cette dernière, les formés sont amenés à vivre différentes situations d'animation qui pourront (ou non) les inspirer dans leurs futures pratiques de tutorat à distance. Par ailleurs, la formation met l'accent sur le respect d'une triple concordance entre les compétences visées, les activités mises en place et les modalités d'évaluation. [less ▲]

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See detailMatrimonial property and Succession under EU Private International Law : a Happy Marriage?
Wautelet, Patrick ULg

Conference (2014, March)

In this presentation, I attempt to examine the relationship between the Succession Regulation (650/2012) and matrimonial property. I do so by looking at the difficulties which could arise both from a ... [more ▼]

In this presentation, I attempt to examine the relationship between the Succession Regulation (650/2012) and matrimonial property. I do so by looking at the difficulties which could arise both from a practical perspective as well as from a more fundamental angle. Attention is given to the future Matrimonial Property Regulation and the need to coordinate it with the Succession Regulation. [less ▲]

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See detailAssessment using e-Health technologies in pediatric psychology: Developing an App on iPad for the Quality of Life Systemic Inventory for Children (QLSI-C)
Toucheque, Malorie ULg; Tilkin, Caroline; Dupuis, Gilles et al

Poster (2014, March)

Objective:Integration of e-Health technologies for purposes of both assessment and intervention has recently become an interest area in pediatric psychology. The purpose of this study is to present ... [more ▼]

Objective:Integration of e-Health technologies for purposes of both assessment and intervention has recently become an interest area in pediatric psychology. The purpose of this study is to present psychometric characteristics of a technology-based (i.e., iPad administration) approach for measuring quality of life (QoL) in children. Methods: Sample consisted of 80 children (8-12 years) recruited from elementary schools in Belgium. They completed the Quality of Life Systemic Inventory for Children (QLSI-C) twice over a two-week delay, in a crossover design that used paper and iPad-based modes of administration. QLSI-C takes a unique approach to assessing QoL relative to existing measures. Specifically, it considers QoL to be the difference (gap score) between the present situation (state score) and the child’s expectations (goal), weighted by the importance (rank) assigned for each life domain. Cronbach’s coefficient was computed to assess internal consistency for each of the four global scores (State, Goal, Gap, Rank). ANOVA was used to assess the equivalence of the new iPad and paper formats. Test-retest reliability was assessed using correlational analysis. Results: Alpha coefficients for the global scores were as follows: State (.87), Goal (.94), Gap (.72), and Rank (.79). ANOVA results indicate that main effects for group (p = 0.75) and time (p= 0.31) were not statistically significant, nor was the interaction effect (p = 0.86) for the QoL score (Gap). Correlations for the test-retest reliability of the 4 global scores ranged from .66 to .90. Conclusions: The iPad format of QLSI-C appears valid in comparison to the original paper format and test-retest stability for the iPad format is good. This technology approach to assessment is more attractive for children, decreases time for administration, and enhances the ease of scoring. Thus, these advantages might encourage both clinicians and researchers to consider using e-Health developments in assessment in pediatric psychology. [less ▲]

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See detailInvestigating iron and organic matter incorporation in growing sea ice
Janssens, J.; Delille, Bruno ULg; de Jong et al

Conference (2014, March)

High concentration of exopolysacharides (EPS) and iron have been found in sea ice surrounding the Antarctic continent. However, the mechanisms leading to that enrichment remain unclear. Scavenging of iron ... [more ▼]

High concentration of exopolysacharides (EPS) and iron have been found in sea ice surrounding the Antarctic continent. However, the mechanisms leading to that enrichment remain unclear. Scavenging of iron by organic matter in seawater and entrainment during sea ice formation are thought to be responsible for the accumulation of iron in sea ice. EPS could also play a role in the iron passive chelative scavenging process in sea ice and in the increase of iron bioavailability. Our study investigates the processes responsible for the accumulation of iron (dissolved, particulate and total dissolvable iron), EPS, dissolved and particulate organic matter, macro-nutrients (silicic acid, nitrate and nitrite, phosphoric acid and ammonium), chlorophyll a and sea ice algae in young sea ice during an Australian-lead spring voyage off East Antarctica (SIPEX II September – November 2012) and a German-lead winter voyage to the Weddell Sea (AWECS June – August 2013). We used a combination of field- (“in situ”) and laboratory- based sea ice growth time-series experiments. In addition different types of newly formed sea ice as pancake ice, grey ice, frost flowers and slush were collected during both voyages as a means to compare and validate the experimental data. To our knowledge, this is the first report on the biogeochemical properties of newly formed Antarctic pack ice samples in the winter. Ice temperature, salinity and textures are also presented to support the biogeochemical observations at the onset of sea ice formation. [less ▲]

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See detailOn the use of O2/Ar and O2/N2 to estimate the biological carbon uptake in landfast sea ice
Zhou, Jiayun ULg; Delille, Bruno ULg; Brabant, F. et al

Poster (2014, March)

Sea ice is one of the largest biomes on Earth. The net community production (NCP) of the microorganisms living in sea ice impacts the dynamics of pCO2 in sea ice, and therefore the CO2 exchanges at the ... [more ▼]

Sea ice is one of the largest biomes on Earth. The net community production (NCP) of the microorganisms living in sea ice impacts the dynamics of pCO2 in sea ice, and therefore the CO2 exchanges at the air-ice-sea interfaces. As oxygen O2 and carbon C are both involved in the photosynthetic and respiration processes, one can theoretically assess NCP (in terms of C uptake) from O2 measurements. However, the concentration of O2 in sea ice depends not only on biological processes (i.e., NCP) but also on physical processes. We present a technique for assessing NCP in sea ice, based on the use of the O2/Ar ratio, which should correct for the physical contribution in O2 variations. We also compare the use of O2/Ar and O2/N2 for deriving NCP, and demonstrate that O2/Ar is more suitable, as it is more sensitive and less affected by gas diffusion and gas bubble formation during sea ice growth and decay than O2/N2. Using O2/Ar, we then provide conservative estimates of NCP in landfast sea ice, from ice cores collected in Barrow, from January through June 2009. The minimum estimate of the NCP in the whole ice cover reached 229 mg C.m-².d-1 in late spring. This is about 20 times higher than the atmospheric C uptake at that time identified from CO2 fluxes measurements at the ice-air interface, and therefore indicates that the main source of C used in the NCP was from the under-ice water. [less ▲]

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See detailDo large companies ignore formal sustainability management controls? An exploration amongst corporate practices
Crutzen, Nathalie ULg; Schaltegger, Stefan

in EMAN (Ed.) Proceedings of the 2014 EMAN conference (2014, March)

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See detailBiological and physical controls on DMS,P dynamics in ice-shelf-influenced fast ice
Carnat, G.; Zhou, Jiayun ULg; Papakyriakou, T. et al

Conference (2014, March)

Dimethylsulfide (DMS) is a volatile sulphur compound produced by the degradation of dimethylsulphoniopropionate (DMSP), a metabolite synthesized by microalgae as i.a. cryoprotectant and osmoregulator. It ... [more ▼]

Dimethylsulfide (DMS) is a volatile sulphur compound produced by the degradation of dimethylsulphoniopropionate (DMSP), a metabolite synthesized by microalgae as i.a. cryoprotectant and osmoregulator. It is also an important climate-active gas, being the primary source of marine-derived sulphate aerosols which play an important role in the earth-atmosphere radiation balance. In the last two decades, there has been an increasing interest in the role of the marine cryosphere in the DMS,P cycle, motivated by repeated observations of very high DMS,P concentrations in sea ice. However, our understanding of the factors driving the spatiotemporal variations of these high concentrations, and hence the fate of the sea ice DMS pool, remains limited. To date, studies have essentially focused on biotic factors, attributing the high DMS,P concentrations to the high biomass of the sympagic communities, and to their strong physiological response to the low temperature and high salinity stresses of the brine habitat. We present here an approach integrating both biotic and abiotic factors, as we investigate the influence of sea ice growth processes and brine dynamics on the DMS,P cycle. We focus on a fast ice site (Cape Evans, McMurdo Sound, Antarctica) under the influence of ice-shelf waters, and provide measurements covering a full cycle of ice growth. We show a good correspondence between isolated maxima of DMS,P in interior ice and the occurrence of platelet crystals in the ice texture. We develop the idea that platelet ice formation in May strongly modifies the production of DMS,P by (1) favoring the incorporation of strong DMSP producers and by (2) exposing these producers to stronger environmental stresses. We then show the influence of the development and decline of a strong diatom bloom from October to November on bottom ice DMS,P concentrations. Finally, we show that the increase in brine volume fraction (permeability) on warming in early December triggers (1) an important release of DMS to the ocean through brine convection, and (2) a vertical redistribution of DMSP across the ice. [less ▲]

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See detailContributions to transnational flood risk management in the Meuse basin
Dewals, Benjamin ULg; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in European Symposium on Flood Frequency Estimation and Implications for Risk Management (2014, March)

Experience in transboundary river basins emphasizes the need for more cooperative transnational water management. In this respect, the Interreg IVB project AMICE aims at developing a shared adaptation ... [more ▼]

Experience in transboundary river basins emphasizes the need for more cooperative transnational water management. In this respect, the Interreg IVB project AMICE aims at developing a shared adaptation strategy of the basin of the river Meuse to the hydrological impacts of climate change. The basin covers parts of France, Belgium, Germany and the Netherlands. The project combines scientific research with innovative natural and structural water retention measures, as well as enhanced transnational crisis management. In this framework, common climate and hydrological scenarios were derived for the time horizons 2021-2050 and 2071-2100. A “coordinated” procedure was set up to conduct the first hydraulic modelling of the entire river Meuse, from its spring to its mouth. For the considered climate scenarios, the increases in future flood levels were found about twice higher in the central part of the Meuse basin compared to the upper and lower parts. This distinctive spatial pattern results from the morphology of the valley. The characteristics of the hydraulic models used for this “coordinated” analysis differed significantly from one region to the other (e.g., 1D vs. 2D, steady vs. unsteady). Therefore, a more refined analysis was undertaken on a 100 km long stretch of the Meuse, crossing the border between Belgium and the Netherlands, using very similar (“harmonized”) models for the whole computation (2D unsteady models). As a result, the influence of using different interconnected models could be appreciated. The results of hydraulic modelling were used to conduct damage assessment based on a common methodology throughout the Meuse basin and combined with landuse change scenarios in the floodplains (change in vulnerability of the floodplains). In turn, several adaptation measures were tested, including upstream water retention, dredging as well as upgrade of flood defences and mobile weirs. Hydrological and hydraulic modelling was also performed for a sub-basin of the river Meuse, partly controlled by two large reservoirs. A detailed model of the operation rules of these reservoirs was implemented. This enabled to investigate the impact of the considered climate change scenarios on the performance of these multi-purpose reservoirs as well as to investigate possible enhancements in the operation rules, which may serve as adaptation measures to compensate for the detrimental effects of climate change. [less ▲]

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See detailAdherence to Continuous Positive Airway Pressure (CPAP) Therapy
Deflandre, Eric; Degey, Stéphanie; BONHOMME, Vincent ULg et al

in CHEST Journal (2014, March), 145

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See detailLe schizophrène : du paradoxe évolutionniste à la psychopathologie éthologique
Englebert, Jérôme ULg

Conference (2014, February 28)

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See detailLa Vierge protectrice des villes
Delfosse, Annick ULg

Conference (2014, February 28)

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See detailSCC-Optimiser la pertinence du parcours patient
WANG, François-Charles ULg

Conference (2014, February 28)

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See detailRevisiting Snu spaces with wavelet leaders to detect non concave and non increasing spectra
Esser, Céline ULg

Poster (2014, February 27)

A multifractal formalism is a formula which is expected to yield the spectrum of singularities of a function from quantities which are numerically computable. The most widespread of these formulas is the ... [more ▼]

A multifractal formalism is a formula which is expected to yield the spectrum of singularities of a function from quantities which are numerically computable. The most widespread of these formulas is the so-called thermodynamic mul- tifractal formalism, based on the Frish-Parisi conjecture. It presents two drawbacks: it can hold only for spectra which are concave and it can only yield the increasing part of the spectrum. This first problem can be avoided using Sν spaces. The second one can be taken care using the wavelet leaders method. In this poster, we present a new multifractal formalism based on a generaliza- tion of the Sν spaces using wavelet leaders. It allows to detect non concave and non increasing spectra. We compare this formalism with the Sν method and the wavelet leaders method. It is based on joint works with F. Bastin, S. Jaffard, T. Kleyntssens and S. Nicolay. [less ▲]

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See detailLa jurisprudence européenne de 2013 en matière de fiscalité directe et ses conséquences en Belgique. Morceaux choisix
Richelle, Isabelle ULg; Traversa, Edoardo

Conference (2014, February 27)

Actualité relative aux conventions préventives de la double imposition et à la jurisprudence de la Cour de justice; le point sur les récentes initiatives de l’OCDE et de la Commission européenne en ... [more ▼]

Actualité relative aux conventions préventives de la double imposition et à la jurisprudence de la Cour de justice; le point sur les récentes initiatives de l’OCDE et de la Commission européenne en matière de lutte contre la planification fiscale agressive et contre l’érosion de l’assiette fiscale. [less ▲]

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See detailThe end of roaming in the forest causes a loss of timber resources: the paradox of slash-and-burn agriculture
Morin-Rivat, Julie ULg; Fayolle, Adeline ULg; Favier, Charly et al

Conference (2014, February 27)

Tropical forests are not believed as pristine anymore. Their structure and specific composition are induced by past climatic and human disturbances over years. In the African moist forests, the emergent ... [more ▼]

Tropical forests are not believed as pristine anymore. Their structure and specific composition are induced by past climatic and human disturbances over years. In the African moist forests, the emergent trees are mainly light-demanding. These trees are considered to derive from the recent disturbances of the last centuries. Most of them are exploited for their timber. However, several of these tree species are currently suffering from a lack of regeneration that threatens the specific diversity of the forests and the sustainability of timber exploitation. Through dendrometric and radiocarbon analyses we found that the majority of the trees of the Congo Basin are not older than 160 years. This corresponds to about the year 1850 when the Europeans colonized the inner regions of Central Africa. By reassembling people along the road axes, the colonial administration reduced the forest roaming. Former activities such as slash and burn agriculture created large openings in the canopy that allowed light-demanding tree species to establish. Currently we observed that timber logging does not provide openings large enough for the recruitment of these species. We thus anticipate that adjustments in forest management strategies shall be made to preserve the forest resources, for instance by recreating the conditions of slash and burn agriculture. [less ▲]

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See detailPlants & metals in soil : the concept of phytoremediation
Evlard, Aricia ULg; Colinet, Gilles ULg; Druart, Philippe

Conference (2014, February 26)

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See detail3. Lutte contre les mauvaises herbes
Henriet, François; Jaunard, Delphine; Gilleman, Alice ULg et al

in Bodson, Bernard; Destain, Jean-Pierre (Eds.) Livre Blanc céréales (2014, February 26)

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See detailOn the use of Belgian Soil Map to predict risk of nitrate and pesticide lixiviation
Bah, Boubacar Billo ULg; Vandenberghe, Christophe ULg; Deneufbourg, Mathieu ULg et al

Poster (2014, February 26)

Pollution by nitrate and pesticides has impacts on drinking water reserves and aquatic systems. Nowadays, this problem is the key point of the European Policy with the implementation of the Water ... [more ▼]

Pollution by nitrate and pesticides has impacts on drinking water reserves and aquatic systems. Nowadays, this problem is the key point of the European Policy with the implementation of the Water Framework Directive (Directive 2000/60/EC). According to these legislations, Member States are supposed to take measures to limit environmental and toxicological effects caused by nitrate and pesticides use. This paper presents three different approaches allowing assessment of diffuse (non-point sources) pollution risks of water resources by nitrate and pesticides. The first approach consists on the interpretation of the geomorphopedological information (geologic substratum type, presence of karst phenomena, soil texture, natural drainage, profile development, type and percent of stoniness, soil thickness, …) provided by the Digital Soil Map of Wallonia. Soil physical characteristics are assessed in terms of soil water percolation/infiltration, runoff, pollutants retention, mineralization, and erosion. Second approach consists on the use of spatially distributed mechanistic models. Nitrate lixiviation from agricultural land to groundwater has been simulated from the SWAT model. Pesticide lixiviation from soil to groundwater has been predicted from the one-dimensional, dynamic, multi-layered model named PEARL (Pesticide Emission Assessment at Regional and Local scales). Model input parameters are mainly extracted from the existing soil physical and physico-chemical, crop and pesticides properties databases. Relevant soil parameters not directly available in existing databases, such as bulk density, hydraulic conductivity, potential evapotranspiration… have been derived from pedotransfers functions. Third approach consists on in situ lixiviation studies by the way of lysimeters. Concentrations measured at the bottom (2 m deep) of lysimeters represent a straight “index of risk” for groundwater and, on the other hand, allow the validation of simulation models used to predict nitrate and pesticides lixiviation risk under different scenarios. The Digital Soil Map of Wallonia, one of the core data source, allows the spatialisation of the predicted lixiviation risk at regional level, providing to the local authorities and the decision makers a tool for the identification of the areas at risk of pollution, where specific monitoring actions and prevention measures for the protection of waters can be implemented. [less ▲]

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See detail6. Lutte intégrée contre les maladies
Duvivier, Maxime; Bataille, Charlotte; Mahieu, Olivier et al

in Bodson, Bernard; Destain, Jean-Pierre (Eds.) Livre blanc céréales (2014, February 26)

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See detail10. Perspectives - 2. Perspectives offertes par la culture en association de froment et de pois protéagineux d'hiver
Pierreux, Jérome ULg; Delaplace, Pierre ULg; Roisin, Christian et al

in Bodson, Bernard; Destain, Jean-Pierre (Eds.) Livre Blanc céréales (2014, February 26)

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See detail9. Nutrition azotée de l'épeautre en Ardenne et en région limoneuse
Escarnot, Emmanuelle ULg; Meza Morales, Walter ULg; De Toffoli, Marc et al

in Bodson, Bernard; Destain, Jean-Pierre (Eds.) Livre blanc céréales (2014, February 26)

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See detail2. Implantation des cultures
Eylenbosch, Damien ULg; Hiel, Marie-Pierre ULg; Meza Morales, Walter ULg et al

in Bodson, Bernard; Destain, Jean-Pierre (Eds.) Livre Blanc Céréales (2014, February 26)

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See detail5. Régulateurs de croissande
Meza Morales, Walter ULg; Monfort, Bruno; Mahieu, Olivier et al

in Bodson, Bernard; Destain, Jean-Pierre (Eds.) Livre Blanc Céréales (2014, February 26)

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See detail4. La fumure azotée
Meza Morales, Walter ULg; Monfort, Bruno; Dumont, Benjamin ULg et al

in Bodson, Bernard; Destain, Jean-Pierre (Eds.) Livre Blanc céréales (2014, February 26)

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See detailEffects of Eisenia fetida on metal uptake of heavy metals from polluted soils by Vicia faba and Zea Mays
Lemtiri, Aboulkacem ULg; Liénard, Amandine ULg; Francis, Frédéric ULg et al

Poster (2014, February 26)

Earthworms are known to increase availability of heavy metals in soils and also play an important role in maintaining the structure and quality of soil. The introduction of earthworms into soils ... [more ▼]

Earthworms are known to increase availability of heavy metals in soils and also play an important role in maintaining the structure and quality of soil. The introduction of earthworms into soils contaminated with metals has been suggested as an aid for phytoremediation processes. In Belgium (Wallonia), a century of industrial metallurgic activities produced significant heavy metal soil pollution. A large q u a n t i t y o f s m e l t e r w a s t e c r e a t e d a g r a d i e n t o f zi n c, lead and cadmium c o n c e n t r a t i o n . The objectives of our study were to evaluate : (i) the potential toxicity of heavy metal elements on the epigeic earthworms Eisenia fetida and on two plants Zea mays and Vicia faba and (ii) to determine the effects of the earthworms on the growth and contaminants phytoextraction process. The combination of behavioural factor measurements (survival, growth, reproduction of earthworms), physico-chemical parameters such as metal absorption, bioaccumulation by earthworms, soil physico-chemical changes, and plant responses (root and shoot elongation, dried biomass,…) provided a valuable indication of pollutant bioavailability and ecotoxicity. After 56-days exposure, the results suggest that adult earthworms have a strong tolerance for heavy metals exposure, but the responses depend on metal elements. Earthworms modify the bioavailable heavy metals in root and shoot in the contaminated soils and their activities alter shoot and root biomass of V. faba and Z. mays. The presence of earthworms led to a change in physico-chemical caracteristics in contaminated soils. These results show that the ecological context for phytoremediation should be broadened by considering earthwom – plant – soil interactions as they influence both plant health and absorption of heavy metals. [less ▲]

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See detailDetection of eye movements specific to drowsiness and their relation with subjective assessment of sleepiness in PVT: A cognitive ergonomic approach
Blavier, Adelaïde ULg; Montagnino, Cédric; Wertz, Jérôme ULg et al

Conference (2014, February 24)

Drowsiness is one of the major factors explaining accidents, particularly in traffic accidents but also in work situations with serious consequences (e.g. medicine). The drowsiness may be assessed by ... [more ▼]

Drowsiness is one of the major factors explaining accidents, particularly in traffic accidents but also in work situations with serious consequences (e.g. medicine). The drowsiness may be assessed by diverse measures that vary from physiological and unconscious data (e.g. EEG) to subjective and conscious evaluation. In their daily life, people are used to evaluate their drowsiness by subjective assessment and research observes a great inter-individual variation in this evaluation. Moreover, the subjective evaluation is dependent on the situation and the risk perceived by the person (e.g., new versus usual situations, simple versus complex environments, etc.). In this theoretical context, our purpose was to investigate the links between 1) objective performance (reaction time) measured by a psychomotor vigilance task (PVT), 2) data from eye movements and 3) subjective assessment of drowsiness (measured with Karolinska Sleepiness Scale, KSS). 12 persons, aged from 20 to 56, participated individually. They were asked to respect a 60% sleep deprivation during the night before the experiment and to not drink any energy drinks the day of the experiment. The experiment was conducted between 1 and 3 PM after a heavy lunch in order to increase the circadian effect. Moreover, the temperature of the room was 25° in order to increase drowsiness. Each participant was asked to perform 4 PVT. However, although 100% of participants performed the first two PVT, only 66% were able to perform the third PVT and only 33% of participants performed the fourth and last PVT. Our results showed an effect of time on objective performance, eye movements and subjective assessment of drowsiness in PVT 1 and 2: significant increase of reaction time, increase of eye closure and perclos, reduction of pupil diameter and increase of subjective drowsiness estimation (KSS). Only the frequency and duration of blinks remained constant across time. In PVT 3 and 4, data from eye movements and objective performance (reaction time) did not vary anymore across the time. Only the subjective estimation of drowsiness (KSS) continued to increase. Furthermore, subjective estimation of drowsiness was differently correlated with eye movements and objective performance across the PVT; it was significantly correlated with reaction time (PVT 1,2,3), blink frequency and duration (PVT 1,2,3), perclos (PVT 1,2,3,4), eye closure (PVT 2,3), pupil diameter (PVT 1,2,3,4). These results are discussed and integrated in an ergonomic approach in order to analyze the links between objective performance, eye movements and subjective assessment of drowsiness. [less ▲]

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See detailInvestigating the Impact of Different Thermal Comfort Models for Zero Energy Buildings in Hot Climates
Attia, Shady ULg; Hensen, JLM

in Proceeding of: Conference on Energy and Indoor Environment for Hot Climates (2014, February 24)

The selection of a thermal comfort model has a major impact on energy consumption of Net Zero Energy Buildings (NZEBs) in hot climates. The objective of this paper is to compare the influence of using ... [more ▼]

The selection of a thermal comfort model has a major impact on energy consumption of Net Zero Energy Buildings (NZEBs) in hot climates. The objective of this paper is to compare the influence of using different comfort models for zero energy buildings in hot climates. The paper compares the impact of applying Givoni’s model, ASHRAE 55 adaptive comfort standard, EN 15251 adaptive comfort standard and EN ISO 7730 on energy consumption and comfort. Using ZEBO and EnergyPlus for energy simulation, an existing prototype of a residential apartment module will be used to evaluate energy performance and thermal comfort in two parametric series. The first one is the result of coupling natural ventilation and mechanical cooling and the second one is guided coupling natural ventilation, mechanical cooling and ceiling fans. Results show a significant difference of cooling loads and total energy generation for the compared comfort models. However, the study remains theoretical and requires post occupancy evaluation for a better reliability of the results. [less ▲]

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See detailAssessing the Thermal Performance of Bedouin Tents in Hot Climates
Attia, Shady ULg

in ASHRAE Energy & Indoor Environment for Hot Climates (2014, February 24)

The aims of this study it to improve conditions inside Bedouin tents shelters and to develop tools to assess shelter quality and comfort. A prototype tent was tested in hot conditions with an internal ... [more ▼]

The aims of this study it to improve conditions inside Bedouin tents shelters and to develop tools to assess shelter quality and comfort. A prototype tent was tested in hot conditions with an internal vapor load. Temperature, humidity measurements and air speed were taken inside the shelter while the external temperature was maintained at 40°C (104°F). Building performance simulation was conducted to produce a simulation model. A model of a tent was constructed using the EnergyPlus simulation software and were calibrated with the test data. The shelter models were simulated in Wadi Rum, Jordan using real data from. The feasibility of heating the tent using only the casual gains from occupants and solar radiation was investigated, although it was found that a tent heated in this way would only be appropriate in spring and autumn. Design issues included coping with stratification of air temperature inside the tent, improving thermal comfort without compromising fabricating the materials cheaply and simply. The validity of the results is limited by the lack of measured data for rates of air infiltration. [less ▲]

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See detailThe Usability of Green Building Rating Systems in Hot Arid Climates
Attia, Shady ULg

in ASHRAE Energy & Indoor Environment for Hot Climates (2014, February 24)

To develop adaptable and context sensitive building rating systems, the present work aimed to evaluate four rating systems that emerged recently in the Middle East. Literature review and cross comparison ... [more ▼]

To develop adaptable and context sensitive building rating systems, the present work aimed to evaluate four rating systems that emerged recently in the Middle East. Literature review and cross comparison analysis showed that the four examined rating systems namely, Green Pyramid Rating System (Egypt), Green Building Standard SI 5281 (Israel), Qatar Sustainability Assessment System (QSAS) and Pearl Building Rating System (UAE) are not enough adopted to local environmental, cultural, historical, societal and economic context. They showed also a comparable similarity since they all imitate the American LEED and British BREEAM rating systems. The paper elaborates on the comparison results and presents recommendations to improve the questioned rating systems and remind designers with the principles and strategies of sustainable design that goes beyond the existing rating systems in hot climate. The evaluation of the four systems might provide a new approach for regional harmonization among the four systems and the development of adaptable and context sensitive rating system. [less ▲]

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See detailStrategic Decision Making For Zero Energy Buildings in Jordan
Attia, Shady ULg; Zawaydeh, Samer

in Proceedings of the 1st International Conference on Energy & Indoor Environment for Hot Climates (2014, February 24)

This paper presents the results of combined economic and computational study of different integrated passive and active design strategies for the Jordanian residential building sector. A representative ... [more ▼]

This paper presents the results of combined economic and computational study of different integrated passive and active design strategies for the Jordanian residential building sector. A representative house prototype, located in Amman is selected as a case study for the zero energy design and performance objective. The aim of the study is to investigate the potential of achieving thermal comfort and delivering thermal and electrical energy demands for existing buildings on site for different Jordanian Cities. Jordan has a semi-arid climate with an annual total irradiation above 2000 bankable kWh/m2 per year with approximately 2000 hours of full sunshine. Therefore, different passive and active design strategies are discussed and compared to reach an annual net zero energy demand for the existing building stock. In order to achieve zero energy buildings certain strategies are examined. For example, internal loads reduction, envelope insulation in addition to the installation of solar water heater and photovoltaic. Based on a month-by–month demand analysis, internal loads and envelope performance are analyzed in order to explore the existing economical potential. Simulation software DesignBuilder is used to examine the strategies proposed to achieve annual net zero energy performance for a prototype. The final result of this study compares the potential and constraints of each strategy and assesses them based on economical feasibility. For the considered location and weather conditions the prototype can provide thermal comfort for occupants and meets the zero energy objectives. The research also proofs that some strategies are cost effective rewarding with a payback period ranging from 3 to 9 years. [less ▲]

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See detailHypoxia and biogeochemical processes concurrently impact acidification in a seasonally stratified coastal marine lake
Hagens, M; Slomp, CP; Meysman, FJR et al

Conference (2014, February 23)

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See detailGradient Boosted Regression Trees in Scikit-Learn
Prettenhofer, Peter; Louppe, Gilles ULg

Conference (2014, February 23)

This talk describes Gradient Boosted Regression Trees (GBRT), a powerful statistical learning technique with applications in a variety of areas, ranging from web page ranking to environmental niche ... [more ▼]

This talk describes Gradient Boosted Regression Trees (GBRT), a powerful statistical learning technique with applications in a variety of areas, ranging from web page ranking to environmental niche modeling. GBRT is a key ingredient of many winning solutions in data-mining competitions such as the Netflix Prize, the GE Flight Quest, or the Heritage Health Price. We give a brief introduction to the GBRT model and regression trees -- focusing on intuition rather than mathematical formulas. The majority of the talk is dedicated to an in depth discussion how to apply GBRT in practice using scikit-learn. We cover important topics such as regularization, model tuning and model interpretation that should significantly improve your score on Kaggle. [less ▲]

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See detailTraitement antihypertenseur : quelles sont les meilleures associations?
Krzesinski, Jean-Marie ULg

Conference (2014, February 22)

Stratégie du traitement de l’HTA en 2014: toujours basée sur le calcul du risque CV. L’HTA, tueur silencieux, est généralement associée à de nombreux autres facteurs de risque CV. Il faut préciser le ... [more ▼]

Stratégie du traitement de l’HTA en 2014: toujours basée sur le calcul du risque CV. L’HTA, tueur silencieux, est généralement associée à de nombreux autres facteurs de risque CV. Il faut préciser le niveau de risque CV en tenant compte de la valeur de PA et des autres F.R. pour décider le moment et le type de traitement ! [less ▲]

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See detailUtilisation d'une application internet pour quantifier la charge de travail chez le rugbyman de haut niveau
Paulus, Julien ULg; Laly, Arnaud; Guns, Sébastien et al

Poster (2014, February 22)

La détection précoce du dépassement (over-reching) (et du syndrôme de surentrainement) est capitale compte-tenu de ses effets négatifs sur la performance. Dans ce processus, le contrôle individuel de la ... [more ▼]

La détection précoce du dépassement (over-reching) (et du syndrôme de surentrainement) est capitale compte-tenu de ses effets négatifs sur la performance. Dans ce processus, le contrôle individuel de la charge d'entrainement du joueur est indispensable. [less ▲]

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See detail1er Colloque Guy Namurois : Livre des résumés
Jidovtseff, Boris ULg; Halleux, Philippe; Lambert, Eric et al

in Jidovtseff, Boris (Ed.) 1er Colloque Guy Namurois : Livre des résumés (2014, February 22)

Colloque multi-disciplinaire en l'honneur de Guy Namurois

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See detailLe contrôle moteur lombopelvien du joueur de footbal élite
GROSDENT, Stéphanie ULg; Demoulin, Christophe ULg; Namurois, Guy et al

in Abstarct Book de la 1ère Journée Guy Namurois (2014, February 22)

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See detailZur Kontinuitätsproblematik in der ostbelgischen Nachkriegszeit
Brüll, Christoph ULg

Conference (2014, February 22)

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See detailPathologies des bétons: causes et effets
Courard, Luc ULg

in Evaluation des structures en béton (2014, February 20)

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See detailDynamics of the aurora at Jupiter
Bonfond, Bertrand ULg; Grodent, Denis ULg; Badman, Sarah et al

Conference (2014, February 19)

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Peer Reviewed
See detailLes herbivores, transformateurs de produits fourragers et de coproduits issus de l'agro-industrie en aliments nobles pour l'homme
Decruyenaere, Virginie; Lessire, Françoise ULg; Beckers, Yves ULg et al

in CRA-W (Ed.) La viande bovine remise en question: De sa production à sa consommation (2014, February 19)

Les prairies recouvrent près de 50% de la surface agricole utile en Wallonie. Dans certaines régions, la prépondérance des prairies dans le paysage wallon se justifie par des contraintes climatiques. Pour ... [more ▼]

Les prairies recouvrent près de 50% de la surface agricole utile en Wallonie. Dans certaines régions, la prépondérance des prairies dans le paysage wallon se justifie par des contraintes climatiques. Pour celles-ci bien souvent, les sommes de température et la durée de végétation active sont faibles et limitent considérablement le choix des cultures susceptibles d’atteindre la maturité avant récolte avec certitude. Dans d’autres régions, les prairies s’imposent davantage en raison de contraintes agronomiques : nature du sol, disposition des parcelles, relief du territoire, intérêt dans la rotation pour les prairies temporaires… Ainsi, la grande majorité des prairies de notre Région ne peut pas être remplacée par des cultures ; elles doivent dès lors être perçues comme une bonne alternative à la valorisation du territoire. Grâce à la présence du rumen en amont de l’estomac, les ruminants ont la capacité de transformer des productions non éligibles pour l’homme, tels que les fourrages et les co-produits des industries agro-alimentaires. Ces aliments, de nature essentiellement fibreuse mais pas pour autant pauvres en protéine et en énergie, sont largement fermentés par les micro-organismes du rumen qui les dégradent en composés plus simples, valorisables ensuite par l’animal. Par ce mécanisme, les ruminants contribuent à transformer ces aliments grossiers en produits nobles, tels que le lait et la viande. On comprend dès lors aisément que la présence des ruminants est étroitement liée aux superficies enherbées, elles-mêmes dépendantes des conditions pédo-climatiques d’une région. Malgré des systèmes de production intensifs et l’amélioration continue du potentiel génétique des animaux, les bovins restent peu dépendants des aliments du commerce comparativement aux autres spéculations animales. Ainsi, selon l’APFACA, de l’ordre de 16% des aliments composés produits en Belgique et importés sont utilisés pour les bovins, dont seulement 1/3 est écoulé dans la filière viande bovine. L’herbe, les produits herbagers et les aliments produits sur l’exploitation tels que le maïs restent donc majoritaires dans la ration des bovins élevés pour la production de viande. La valorisation de l’herbe et des produits herbagers dépend fortement des performances zootechniques recherchées. Les objectifs de croissance sont établis, en autre, sur base des prix offerts par la cheville variant avec les catégories d’âge et de poids d’abattage. Ces dernières années, il semble que les animaux abattus un peu plus tardivement soient moins dépréciés qu’auparavant, facilitant la formulation de rations à base de matières premières herbagères. A l’inverse, l’intensification dans le but de produire des animaux abattus plus jeunes ou à un poids supérieur, implique une croissance plus soutenue, et de ce fait la distribution de rations plus denses en énergie. Pour la formulation de telles rations, certains coproduits disposent de valeurs nutritionnelles intéressantes, permettant de satisfaire des besoins nutritionnels élevés, tout en conservant une certaine autonomie alimentaire. Leur valorisation au niveau local représente en outre un intérêt considérable pour la rentabilité des industries agro-alimentaires qui, sans la présence de l’animal, devraient trouver d’autres débouchés pour les coproduits sous peine d’être dans l’obligation de financer leur élimination. Cet exposé a pour objectif d’illustrer les potentiels, mais aussi les limites, des aliments produits localement pour les bovins viande, que ce soit selon leur type (vache de réforme- taurillon…), leur race et leurs performances zootechniques, mais aussi l’intérêt de ces aliments en termes d’efficiences alimentaire et économique. Il analyse les atouts et faiblesses de la spéculation viande bovine en ne se limitant pas à l’échelle de l’animal seul, mais en le replaçant en tant que véritable maillon de la chaîne agro-alimentaire. Ce positionnement permet non seulement de mieux cerner les enjeux de ces élevages au niveau de la production primaire, mais aussi leur importance dans les secteurs amont et aval. [less ▲]

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See detailLes herbivores, transformateurs de produits fourragers et de coproduits issus de l'agro-industrie en aliments nobles pour l'homme
Decruyenaere, Virginie; Lessire, Françoise ULg; Beckers, Yves ULg et al

in CRA-W (Ed.) La viande bovine remise en question: De sa production à sa consommation (2014, February 19)

Les prairies recouvrent près de 50% de la surface agricole utile en Wallonie. Dans certaines régions, la prépondérance des prairies dans le paysage wallon se justifie par des contraintes climatiques. Pour ... [more ▼]

Les prairies recouvrent près de 50% de la surface agricole utile en Wallonie. Dans certaines régions, la prépondérance des prairies dans le paysage wallon se justifie par des contraintes climatiques. Pour celles-ci bien souvent, les sommes de température et la durée de végétation active sont faibles et limitent considérablement le choix des cultures susceptibles d’atteindre la maturité avant récolte avec certitude. Dans d’autres régions, les prairies s’imposent davantage en raison de contraintes agronomiques : nature du sol, disposition des parcelles, relief du territoire, intérêt dans la rotation pour les prairies temporaires… Ainsi, la grande majorité des prairies de notre Région ne peut pas être remplacée par des cultures ; elles doivent dès lors être perçues comme une bonne alternative à la valorisation du territoire. Grâce à la présence du rumen en amont de l’estomac, les ruminants ont la capacité de transformer des productions non éligibles pour l’homme, tels que les fourrages et les co-produits des industries agro-alimentaires. Ces aliments, de nature essentiellement fibreuse mais pas pour autant pauvres en protéine et en énergie, sont largement fermentés par les micro-organismes du rumen qui les dégradent en composés plus simples, valorisables ensuite par l’animal. Par ce mécanisme, les ruminants contribuent à transformer ces aliments grossiers en produits nobles, tels que le lait et la viande. On comprend dès lors aisément que la présence des ruminants est étroitement liée aux superficies enherbées, elles-mêmes dépendantes des conditions pédo-climatiques d’une région. Malgré des systèmes de production intensifs et l’amélioration continue du potentiel génétique des animaux, les bovins restent peu dépendants des aliments du commerce comparativement aux autres spéculations animales. Ainsi, selon l’APFACA, de l’ordre de 16% des aliments composés produits en Belgique et importés sont utilisés pour les bovins, dont seulement 1/3 est écoulé dans la filière viande bovine. L’herbe, les produits herbagers et les aliments produits sur l’exploitation tels que le maïs restent donc majoritaires dans la ration des bovins élevés pour la production de viande. La valorisation de l’herbe et des produits herbagers dépend fortement des performances zootechniques recherchées. Les objectifs de croissance sont établis, en autre, sur base des prix offerts par la cheville variant avec les catégories d’âge et de poids d’abattage. Ces dernières années, il semble que les animaux abattus un peu plus tardivement soient moins dépréciés qu’auparavant, facilitant la formulation de rations à base de matières premières herbagères. A l’inverse, l’intensification dans le but de produire des animaux abattus plus jeunes ou à un poids supérieur, implique une croissance plus soutenue, et de ce fait la distribution de rations plus denses en énergie. Pour la formulation de telles rations, certains coproduits disposent de valeurs nutritionnelles intéressantes, permettant de satisfaire des besoins nutritionnels élevés, tout en conservant une certaine autonomie alimentaire. Leur valorisation au niveau local représente en outre un intérêt considérable pour la rentabilité des industries agro-alimentaires qui, sans la présence de l’animal, devraient trouver d’autres débouchés pour les coproduits sous peine d’être dans l’obligation de financer leur élimination. Cet exposé a pour objectif d’illustrer les potentiels, mais aussi les limites, des aliments produits localement pour les bovins viande, que ce soit selon leur type (vache de réforme- taurillon…), leur race et leurs performances zootechniques, mais aussi l’intérêt de ces aliments en termes d’efficiences alimentaire et économique. Il analyse les atouts et faiblesses de la spéculation viande bovine en ne se limitant pas à l’échelle de l’animal seul, mais en le replaçant en tant que véritable maillon de la chaîne agro-alimentaire. Ce positionnement permet non seulement de mieux cerner les enjeux de ces élevages au niveau de la production primaire, mais aussi leur importance dans les secteurs amont et aval. [less ▲]

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See detailRecent advances and improvements in computerized adaptive testing with the R package catR
Magis, David ULg; Barrada, Juan

Conference (2014, February 14)

The purpose of this talk is to present recent advances and developments of the R package catR. This package allows for random generation of response patterns under computerized adaptive testing (CAT) and ... [more ▼]

The purpose of this talk is to present recent advances and developments of the R package catR. This package allows for random generation of response patterns under computerized adaptive testing (CAT) and holds various options to select the first items, estimate ability, select the next item, stop the test and return final results. Two main improvements were realized. First, several rules for next item selection were added, among others, Kullback- Leibler, progressive and proportional methods. Second, catR was limited to dichotomous IRT models so far. The most recent update allows now for several polytomous IRT models, such as partial and generalized partial credit model, graded and modified graded response models, rating scale model, and nominal response model. All improvements will be shortly presented, both from a theoretical point of view and in terms of practical implementation in catR. If possible, several illustrative examples will be displayed in a short live demonstration of catR. [less ▲]

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See detailDevelopment of educational info capsules proposing instructional strategies aiming to deal with overweight and obese students
Cloes, Marc ULg; LEBRETHON, Marie-Christine ULg; Feron, Isaline

Conference (2014, February 13)

Irwin et al. (2003) pointed out the principles that quality PE teachers should incorporate into their pedagogical practice in order to take into account the increasing number of overweight and obese ... [more ▼]

Irwin et al. (2003) pointed out the principles that quality PE teachers should incorporate into their pedagogical practice in order to take into account the increasing number of overweight and obese students in their classes. Fighting against obesity is so complex that no simple solution can be proposed. It means that the development of specific tools providing PE teachers with new instructional strategies inspired from public health is needed (Prusak et al., 2011). Inclusion of overweight students into PE can be linked with a social ecological model (Li & Rukavina, 2012). Even if PE teachers are able to develop and implement specific instructional strategies, it seems that they need support from health experts (Cloes et al., 2013). Internet, continuing professional development activities, and educational info capsules were identified as the preferred supports to be used by the practitioners (Cloes et al., 2014). The aims of this study were to produce and validate three pedagogical capsules focusing on specific concerns of PE teachers as well as to analyze the procedure of validation. Using an extensive analysis of the literature, the researchers first identified theoretical and practical resources to be mobilized in the understanding and development of solutions for the selected problems: (1) Students’ lack of awareness about the risks of overweight and obesity; (2) Constraints associated with the motor/physical disabling; (3) Parents’ lack of awareness about PA impact on health. The capsules were then submitted to 11 experts (health specialists, health educators, psychologists, PE teachers) who had to analyze the documents. They acknowledged the content and form of the capsules. Minor changes were requested in order to finalize them. The proposed evaluation sheet was also validated but face-to-face assessment was recommended. Dissemination of the existing capsules as well as development of additional ones should be the next steps of this project. [less ▲]

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See detailL'architecture Art nouveau à Liège (1895-1914)
Charlier, Sébastien ULg

Conference (2014, February 13)

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See detailImportance des récentes variations pluviométriques à Djibouti et besoins de quantification de leurs impacts
Mahamoud, Ayan; Nour Ayeh, Moustapha; Saad, Osman et al

Poster (2014, February 12)

Ces dernières décennies, l’Afrique de l’Est souffre d’une longue et lente détérioration pluviométrique. De 2007 à 2011, la ville de Djibouti a enregistré un déficit de 73% des précipitations moyennes ... [more ▼]

Ces dernières décennies, l’Afrique de l’Est souffre d’une longue et lente détérioration pluviométrique. De 2007 à 2011, la ville de Djibouti a enregistré un déficit de 73% des précipitations moyennes annuelles par rapport à la moyenne de 30 ans (1981-2010). Pour caractériser la sécheresse actuelle, nous analysons une série pluviométrique reconstruite pour Djibouti-Ville de 1901 à 2013, les données de terrain permettant d’illustrer les impacts de ces variations pluviométriques. Les précipitations enregistrées à Djibouti ne présentent aucune tendance sur le long terme (1901-2013). Par contre, ces dernières années montrent une très grande variabilité: le suivi de la moyenne pluviométrique sur 10 ans est à son maximum en 1998 (215 mm) et à son minimum en 2013 (79 mm). Depuis 2007, la pluie totale annuelle ne dépasse plus les 100 mm. C’est cette succession d’années déficitaires qui est problématique. Cette sécheresse sans précédent va mettre de nombreuses familles des zones rurales (de Djibouti, d’Ethiopie et de Somalie) sur la route. Cette migration a pour point de chute la ville de Djibouti où des quartiers neufs se créent, comme Buldhuqo. Totalement inexistant en 2004, il explose après 2009. Les derniers arrivants s’installent dans le fond de l’oued, là même où la zone était inondée en 2004 et 2009 suite à des pluies courtes mais intenses. La prochaine pluie extrême, l’exposition de ces populations précaires aux risques hydrologiques sera maximale. [less ▲]

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See detailNew mass spectrometry based methodology to sequence a whole snake venom
Echterbille, Julien ULg; Boulanger, Madeleine; Degueldre, Michel ULg et al

Poster (2014, February 10)

Animal venoms are complex chemical cocktails, comprising wide ranges of biologically active reticulated peptides that target with high selectivity and efficacy varieties of membrane receptors. Assuming ... [more ▼]

Animal venoms are complex chemical cocktails, comprising wide ranges of biologically active reticulated peptides that target with high selectivity and efficacy varieties of membrane receptors. Assuming the fact that each of the 170,000 venomous species reported can produce more than 250 bioactive toxins, at least 40,000,000 bioactive peptides and proteins may be discovered. Among the four described species of mambas, Eastern Jameson’s mamba (Dendroaspis jamesonii kaimosae) venom is the less characterized since only 9 peptides are referenced in database. This work aims at developing a new strategy devoted to the deep analysis of animal venoms. Our approach consists in a first separation of the venom using cation exchange chromatography. Each primary fraction is then purified a second time by classical RP-HPLC. A total of 328 fractions, containing amongst 1 and 4 toxins, are finally collected. MALDI-MS analysis of each fraction is done in order (1) to obtain information about masses and (2) to obtain sequences of toxins thanks to MALDI-In Source Decay (ISD) dissociation coupled with on MALDI target plate reduction of the peptides. ISD has already been demonstrated efficient for toxin sequencing, and especially when using 1,5-DAN as reducing matrix. ISD yields to sequences that cover more than 50% of peptide sequences by series of singly charged c-type ions. Thanks to this methodology, we were able to obtain 85% of satisfactory results i.e. spectra giving quite long tags of amino acids (up to 20 residues). As a way to validate our method, a tag coming from ISD spectrum interpretation has found a match in database for an Eastern Jameson’s mamba toxin. The global sequence has then been obtained by extrapolation on the ISD spectrum. Since ISD spectra are simpler than classical MS/MS spectra, automation of spectra interpretation, difficult with other fragmentation techniques (CID, ETD…), is implementable. In the near future, sequences obtained with this approach will be used to direct tests of biological activity through sequence homologies with already known ligands for different kinds of membrane receptors. [less ▲]

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See detailMolecular dynamic simulation of the cyclic lipodepsipeptide Pseudodesmin A self-assembly
Crowet, Jean-Marc ULg; Sinnaeve, Davy; Fehér, Krisztina et al

Conference (2014, February 10)

Pseudodesmine A is a cyclic lipodepsipeptide of nine residues which presents a moderate antibacterial activity and whose structure has been resolved by X-ray and NMR1,2. In acetonitrile, Pseudodesmine A ... [more ▼]

Pseudodesmine A is a cyclic lipodepsipeptide of nine residues which presents a moderate antibacterial activity and whose structure has been resolved by X-ray and NMR1,2. In acetonitrile, Pseudodesmine A is monomeric while in chloroform it has the same structure but assemble in a supramolecular complex. This structure could associate with membranes and be responsible of the biological activity of this peptide. Comparison of the NMR data between the two solvents has given indications on the intermolecular contacts that arise in chloroform and a model for the self association was proposed2,3. To study in more details this assembly, molecular dynamics have been carried on. In acetonitrile, the peptide show transient interactions while in chlorofom interactions between monomers was always observed. As stated in Sinnaeve et al. in 2009, these interactions arise mainly between the backbone protons of the LEU1 and the GLN2, the GLN2 sidechain and the loop located on the opposite end of the monomer structure. From 10 simulations of dimerization, hydrogen bonds were followed and specific interaction patterns were identified regarding the hydrogen bonds formed. The peptide interactions are mainly described by 13 interaction patterns; 8 with the peptides in a linear configuration, 1 perpendicular and 4 with peptides side by side. The patterns are characterized by 2 to 4 hydrogen bonds. From the linear dimer, it is possible to reconstruct filaments and, by combining a linear and a lateral dimer, it is possible to build fibrils with multi filaments, as expected in the NMR derived model. Besides, the perpendicular dimer can gives peptide rings that can also explain the potential ability of this peptide to form ion pores in membranes. 1. Sinnaeve, D., Michaux, C., Van hemel, J., Vandenkerckhove, J., Peys, E., Borremans, F. a. M., Sas, B., Wouters, J. and Martins, J. C. Tetrahedron 2009, 65, 4173–4181. 2. Sinnaeve, D., Hendrickx, P. M. S., Van Hemel, J., Peys, E., Kieffer, B. and Martins, J. C. Chemistry (Weinheim an der Bergstrasse, Germany) 2009, 15, 12653–62. 3. Sinnaeve, D., Delsuc, M.-A., Martins, J. C. and Kieffer, B. Chemical Science 2012, 3, 1284. [less ▲]

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See detailConstraints experienced by physical education teachers with overweight and obese students
Cloes, Marc ULg; Feron, Isaline; LEBRETHON, Marie-Christine ULg

Conference (2014, February 10)

Despite ‘antifat’ attitude of some PE teachers (Greenleaf & Weiller, 2005) and the PE public relations problem in regard to how obese students are treated (Irwin et al., 2003), it seems evident that this ... [more ▼]

Despite ‘antifat’ attitude of some PE teachers (Greenleaf & Weiller, 2005) and the PE public relations problem in regard to how obese students are treated (Irwin et al., 2003), it seems evident that this school subject represents a key element in the involvement of the education sector in the fight against the worldwide escalating global epidemic of obesity (Tappe & Burgeson, 2004). In fact, PE teachers consider that they lack of specific knowledge to implement instructional strategies dealing with overweight and obese students (Cloes & Ziant, 2009). Some authors proposed models to illustrate constraints that PE teachers encounter in their classes with obese students and their potential solutions (Cloes et al., 2013; Rukavina et al., 2010). On the other hand, data are missing when identifying those that are considered as their main concerns and the ways that they would prefer to receive some support regarding this specific topic. This study is focused on these two aspects. Five hundred thirteen PE teachers fulfilled an online questionnaire (Lickert scales) in which they had to determine (1) the perceived importance of 20 problems proposed by PE teachers and validated by 8 experts; (2) their relative interest toward the reception of support aiming to deal with those problems; (3) their preference for receiving information about the potential instructional strategies. Based on the answers, the top 3 problems are: (1) Students’ lack of awareness about the risks of overweight and obesity; (2) Constraints associated with the motor/physical disabling; (3) Parents’ lack of awareness about physical activity impact on health. Internet (3.49±.6/4), continuing professional development activities (3.29±.8/4), and educational info capsules (3.07±.8/4) were identified as the main resources that PE teachers would use preferentially. This study provides useful information for PE teachers’ educators who should develop now material to be shared with the practitioners. [less ▲]

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See detailAllo- and autoinhibition in barley and great brome: a laboratory study
Bouhaouel, Imen ULg; Gfeller, Aurélie; Fauconnier, Marie-Laure ULg et al

Conference (2014, February 08)

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See detailRealized niche of eight endemic plant species of Katangan Copperbelt (D.R. Congo): implications for copper species conservation
Boisson, Sylvain ULg; Seleck, Maxime ULg; Lebrun, Julie et al

Poster (2014, February 07)

South of the Katanga province (D.R. Congo), a unique vegetation grows on soils developed on 100 Cu-Co outcrops among the most important in the world (katangan Copperbelt). These outcrops form of isolated ... [more ▼]

South of the Katanga province (D.R. Congo), a unique vegetation grows on soils developed on 100 Cu-Co outcrops among the most important in the world (katangan Copperbelt). These outcrops form of isolated hills in the landscape hosting vegetal communities evolving along the mineralization gradient. More than 600 metallophytes can be found in these communities with some 32 strict endemics solely known from mineralized soils. These species present physiological and biological adaptations allowing them to tolerate toxic levels of metals in soils. The unique characteristics of most endemics are seriously threatened by the intense mining activities in the region thus also threatening the high genetic potential to be used in development of polluted soils’ restoration strategies. In an effort to characterize the ecology of these species, we model ecological niches of eight endemic species along copper-cobalt gradients. For each species, three sites were prospected and transects set. Along these, five plots where the species occurred were selected: at both the extremities of the gradient and at 1st quartile, median and 3rd quartile. In each plot, individuals of the particular species were counted and composite soil samples collected. Available EDTA Cu-Co values were determined and niches modeled for both metals through the kernel density method in R 3.0.1 (package ‘vioplot’). Results show that ecological niches of the selected endemics are distributed between Cu-soil values of 50 and 11 000 mg.kg-1 and between Co values between four and 1500 mg.kg-1. Six species occur in the lower 100 mg.kg-1concentrations of Co. As for the Cu gradient, two species present ecological optimums over 3000 mg.kg-1. This variation of ecological niches along the gradients indicates a need of adequacy between species conservation strategies and soils’ metal contents. Four of the eight studied species should be conserved on soils contaminated with some 500 mg Cu.kg-1 and 30 mg Co.kg-1. For others, precise conservation actions need to be undertaken. [less ▲]

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See detailOld inks: pigments extracted from plants
Despy, Jessica; Wymeersch, Noémie; Bouchat, Isabelle et al

in BOOK OF SHORT ABSTRACTS - POSTER PRESENTATIONS 19TH NATIONAL SYMPOSIUM ON APPLIED BIOLOGICAL SCIENCES (2014, February 07)

Thousands of years ago, natural pigments were discovered and they have been used ever since. Indeed, prehistoric people already used them to paint the walls of the caves in which they were living. A ... [more ▼]

Thousands of years ago, natural pigments were discovered and they have been used ever since. Indeed, prehistoric people already used them to paint the walls of the caves in which they were living. A significant example of this is the Cosquer cave (-19,000 to -27,000 years) located near Marseilles. Pigments and dyes can be classified into two broad categories and five families: natural pigments and dyes and those called artificial. The first one of these five families includes the mineral pigments. Among these we can find the clays (yellow ochre, red ochre, green clay, brown clay) and the stones like lapis lazuli (blue). The second and third families gather the organic dyes and pigments. Those that have vegetal origins like indigo (blue) and madder (red) compose the second family and those that have animal origins like cochineal (red) and kermes dyers (carmine) form the third family. One family includes pigments and dyes stemming from chemical reactions such as verdigris or red lead (family 4) and the other one is made of the miscellaneous inks such as iron-gall type who are vegetal and mineral one (family 5). All these pigments, although they have been used for centuries, have been replaced by synthetic dyes from the oil industry at the end of the 19th century. Indeed, they have the advantage of reproducibility of the properties unlike natural pigments. But the scarcity of oil causes a renewed interest in natural preparations. We report the extraction of pigments from plants. [less ▲]

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See detailImpact of abiotic stresses on volatile organic compound production of field crops and grasslands
Digrado, Anthony ULg; Mozaffar, Ahsan ULg; Bachy, Aurélie ULg et al

Poster (2014, February 07)

Abiotic and biotic stresses are known to alter biogenic volatile organic compound (BVOC) emission from plants. With the climate and global change, BVOC emissions are likely to increase. This increase on ... [more ▼]

Abiotic and biotic stresses are known to alter biogenic volatile organic compound (BVOC) emission from plants. With the climate and global change, BVOC emissions are likely to increase. This increase on BVOC emissions could be driven by many environmental parameters like temperature, ozone and light availability for photosynthesis although it is still difficult to predict the impact of some environmental parameters, environmental controls on BVOC emission being species and BVOC-dependent. These BVOC are involved in a wide range of interactions of plants with their environment and these interactions could be affected by the global change. Moreover, BVOC also play a key role in the atmospheric chemistry and may contribute to ozone formation and an increase in methane lifetime, strengthening the global change. Yet, due to technical limitation, there are few studies examining the impact of multiple co-occurring stresses on BVOC emission at the ecosystem level although stress combination is probably more ecologically realistic in field. In the CROSTVOC (for CROp STress VOC) project, the impact of abiotic stresses (e.g. heat, drought, ozone and grazing) on BVOC emission will be investigated for field crops (maize and wheat) and grassland both at the ecosystem and plant scale. [less ▲]

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See detailA diachronic analysis of the dynamic of two cities: Kisangani and Lubumbashi (Democratic Republic of Congo): How do the extension and/or of the densification of these cities impact the urban internal and peripheral ecosystems?
Andre, Marie ULg; Mahy, Grégory ULg; Lejeune, Philippe ULg et al

Poster (2014, February 07)

The dynamics of two cities between two years (2002 and 2010 for Kisangani; 2002 and 2008 for Lubumbashi, both part of the Democratic Republic of Congo) have been examined in order to estimate how their ... [more ▼]

The dynamics of two cities between two years (2002 and 2010 for Kisangani; 2002 and 2008 for Lubumbashi, both part of the Democratic Republic of Congo) have been examined in order to estimate how their extension and/or of the densification have impacted the urban internal and peripheral ecosystems. This study singularizes itself from the subjective ones by its quantified and objective approach based on landscape ecology. This discipline assumes that the landscape pattern description is important because, according to its central hypothesis called “pattern-process paradigm”, the ecological processes influence landscape structure and vice versa. Composition metrics, which are commonly used in landscape ecology, describe the pattern among other things in quantifying the presence and the number of patches from the various classes within the landscape. For each city two SPOT 5 images were classified with a oriented-object supervised approach; then built area proportion index, a composition landscape metric, has been evaluated in order to 1) identify the extent of each area (urban, suburban, rural) within the urban-rural gradient, 2) quantify the dynamic of the different areas in the urban-rural gradient during the last decade and 3) quantify the effect of a decade of urban and suburban growth on ecosystems. The similarities and differences between these cities, relevance and gaps in the method have then been identified and discussed. [less ▲]

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See detailDevelopment of formulated elicitors to control bioagressors of wheat: which interests?
Le Mire, Géraldine ULg; Deleu, Magali ULg; Ongena, Marc ULg et al

Poster (2014, February 07)

Crop plants are constantly exposed to a wide range of environmental stresses that can cause major productivity loss. Fungicide treatments are the most efficient disease control methods used up to now ... [more ▼]

Crop plants are constantly exposed to a wide range of environmental stresses that can cause major productivity loss. Fungicide treatments are the most efficient disease control methods used up to now. However, the environmental and health issues caused by these chemicals make it urgent to develop safer methods for pathogen control. In the optic of a sustainable agriculture, several biocontrol tools have been developed during the last decades. Elicitors are increasingly subject to research as interesting alternatives to phytosanitary products. Yet, few efficient formulations exist on the market, and no product has been designed specifically to protect wheat crops. This study will thus focus on the the manipulation of host natural defenses through the use of elicitors as a preventive treatment against major wheat diseases such as Septoria tritici, Fusarium graminearum and Fusarium culmorum. [less ▲]

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See detailContribution to the study of alliinase, the active principle of garlic
DETHIER, Bérénice ULg; Ponchaux, Julien; Laloux, Morgan et al

Poster (2014, February 07)

Alliinase is a crucial enzyme in the Allium genus. The conversion of its substrates, cysteine sulfoxides, into volatile thiosulfinates is an important mechanism in the defence of the plant. It also ... [more ▼]

Alliinase is a crucial enzyme in the Allium genus. The conversion of its substrates, cysteine sulfoxides, into volatile thiosulfinates is an important mechanism in the defence of the plant. It also provides the typical pungent flavour of garlic. As a matter of fact, the thiosulfinates decompose in a range of organosulfur compounds (OSC) known for their biological activities (antioxidant, anticancer, anti-diabetes properties, etc.). The environment of the decomposition of the thiosulfinates determines the type and amount of products released. A deeper knowledge of the conditions that form each OSC could help us in the preparation of garlic-based nutraceutics in the perspective of healthier food consumption. This study aims to improve the extraction and purification the enzyme alliinase in order to perform the reaction between the enzyme and its substrates and assess the potentialities of garlic preparations. Three methods have been applied to evaluate the efficiency of the extractions and purifications of the enzyme. A first idea of the purity of the enzyme is given by an electrophoresis separation of each sample on a polyacrylamide gel (SDS-PAGE). The protein content is then measured by UV-vis spectrometry with Lowry-Folin reagent for the coloration and BSA as an external standard. Finally, the specific activity is assessed by an indirect measure of the pyruvate (released as a co-product): the addition of NADH and lactate dehydrogenase turns the pyruvate in lactate, and the disappearance of NADH is measured by UV-vis spectrometry at 340 nm. The extraction of the enzyme from garlic was performed either by PEG 8000 precipitation or by ammonium sulphate precipitation. Two purifications were tested: affinity chromatography (on ConA) and size-exclusion chromatography. The combination of the ammonium sulphate process with the ConA chromatography provided the purest enzyme, with the best activity but a lower yield than the size-exclusion process. Finally the stability of the enzyme has been assessed at 4, -20 and -80 °C, showing that the enzyme could be kept at -80 °C for over 4 months without deterioration, while activity loss was observed at higher temperature. [less ▲]

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See detailEffect of sun-drying on flavonoïd composition and antioxidant activity of three dark fig varieties
Bachir Bey, M.; Richard, Gaetan ULg; Fauconnier, Marie-Laure ULg et al

Poster (2014, February 07)

The aim of the study was to investigate the effect of sun-drying on individual flavonoïd and antioxidant activities of three dark fig varieties (Azenjar, Bouankik, and Aberkane). Flavonoïd compounds were ... [more ▼]

The aim of the study was to investigate the effect of sun-drying on individual flavonoïd and antioxidant activities of three dark fig varieties (Azenjar, Bouankik, and Aberkane). Flavonoïd compounds were identified and quantified using high-performance liquid chromatography. The results showed that all samples significantly differed in their flavonoïd compositions. [less ▲]

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See detailPrerequisites for a Black locust genomic selection program
Verdu, Cindy ULg; Mengal, Coralie ULg; Henrotay, Frédéric ULg et al

Poster (2014, February 07)

The use of renewable resources as an alternative to fossil fuels has become a priority. Efficient use of forest as a resource for energy and green chemistry purposes require the development of suitable ... [more ▼]

The use of renewable resources as an alternative to fossil fuels has become a priority. Efficient use of forest as a resource for energy and green chemistry purposes require the development of suitable selected genotypes that are competitive and ready to meet the challenges of global change. In this context, the black locust, Robinia pseudoacacia L., is a very promising species which has many advantages in the context of current global change: high phenotypic plasticity, drought resistance, high biomass production and fixation of atmospheric nitrogen. The genetic improvement of woody species using traditional methods can take between 20 to 30 years. These times can be greatly reduced with the development of new selection methods such as genomic selection. Before starting a genomic selection program, it is necessary to 1) develop new molecular markers to achieve a very dense genetic map for genomic selection, 2) study the genetic diversity of the species present in Belgium and compare it with that of the native area, 3) study the structure and the relatedness of different populations, 4) establish a core collection gathering the most genetically diverse individuals, and 5) as black locust is an exotic species, verify its invasiveness in Belgium. These 5 steps will be detailed and the first results obtained will be discussed. [less ▲]

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See detailUse of lipases for the kinetic resolution of lactic acid esters in heptane or in a solvent free system
Richard, Gaetan ULg; Nott, Katherine; Nicks, François et al

Poster (2014, February 07)

This poster illustrates the kinetic resolution of lactic acid esters using CAL-B as catalyst. The racemic mixture is resolved in heptane and even in a solvent free system.

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See detailUse of Near Infrared Hyperspectral Imaging (NIR-HSI) and chemometric tools to dicriminate wheat roots and straws in soil
Eylenbosch, Damien ULg; Fernandez Pierna, Juan Antonio; Baeten, Vincent et al

Poster (2014, February 07)

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See detailAnalyzing relationships between cattle grazing behavior and pasture attributes using the inertial measurement unit of a mobile phone.
Andriamandroso, Andriamasinoro ULg; Lebeau, Frédéric ULg; Bindelle, Jérôme ULg

Poster (2014, February 07)

The recent technological developments are boosting the opportunities of accurate method to monitor resource use efficiency in agriculture and in their wake, precision livestock farming (PLF) has ... [more ▼]

The recent technological developments are boosting the opportunities of accurate method to monitor resource use efficiency in agriculture and in their wake, precision livestock farming (PLF) has experienced huge developments over the past decade. These developments focus on the optimization of individual performances of farm animals as opposed to herd management. The aim of this paper is to explore a method to detect accurately and to analyze changes in cattle's behaviors on pasture during grazing time using signals from the inertial measurement unit (IMU) of mobile devices as a possible tool to manage individual grazing behavior. Commercial iPhones or iPods, which include a 3-axis accelerometer, a gyroscope and a GPS sensor, are fitted on a halter and placed on the neck of grazing cows. The acquired IMU data are recovered using an open source application (Sensor Data, Wavefrontlabs) and analyzed in a “white-box” model of the cows’ movements. First results using time-domain analysis allowed the detection of grazing behaviors showed accuracies ranging between 84% and 96%, attesting the relevancy of the method. Refined signal processing method will improve the detection but will also inform more about the relative link between the behaviors and the pasture attributes such as sward height, composition and nutritive value. [less ▲]

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See detailAnd the winner is ... When =f and pAj=f play hide-and-seek
Winand, Jean ULg

Conference (2014, February 07)

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See detailEfficient computation of genomically-enhanced inbreeding coefficients
Faux, Pierre ULg; Gengler, Nicolas ULg

Poster (2014, February 07)

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See detailBiofilms from entomopathogenic fungi in mosquito control
Bawin, Thomas ULg; Boukraa, Slimane; Seye, Fawrou et al

Poster (2014, February 07)

Mosquitoes (Diptera: Culicidae) are zoonotic vectors of medical and veterinary importance. As part of an integrated vector control, metabolites secreted by entomopathogenic fungi could be developed as ... [more ▼]

Mosquitoes (Diptera: Culicidae) are zoonotic vectors of medical and veterinary importance. As part of an integrated vector control, metabolites secreted by entomopathogenic fungi could be developed as biopesticides. In this context, filamentous microorganisms growing on a support as biofilm in a liquid medium would offer several advantages in bioreactor regarding performances and metabolites recovery. The production of toxic metabolites by an entomopathogenic fungus Aspergillus flavus in such conditions was assessed. Three initial inoculum levels, i.e. 10^1, 10^3 and 10^6 spores/ml of PYG medium, have been tested in shake flask with or without support. Toxicity tests were performed on Culex quinquefasciatus larvae using dilutions of 1, 2, 4, 6, 8 and 10% of liquid cultures. The results indicated that A. flavus tends to form pellets in submerged culture; the size and the amount of pellets was affected by the initial inoculum level of spores. Under similar conditions, the filaments fixed on a support and didn’t appear in free form in the liquid. Toxicity tests revealed differences between both free and fixed forms. All combined conditions, LC50s ranging up to dilutions of 2.2 and 4.8% were observed within 48 hours. Secretomes could be compared between these culture conditions by proteomic and metabolomic approaches. [less ▲]

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See detailField bordering flower strips as source of lipids
Paul, Aman ULg; Danthine, Sabine ULg; Stephanie, Heuskin et al

Poster (2014, February 07)

Field bordering flower strips not just only improves the biodiversity but also serves as a source of beneficial compounds. Some of the plants in these strips can be really interesting source of lipids ... [more ▼]

Field bordering flower strips not just only improves the biodiversity but also serves as a source of beneficial compounds. Some of the plants in these strips can be really interesting source of lipids, the oils extracted from their seeds can be important for food, pharmaceutical and cosmetics industries. Six species of plants from flowering strips in Belgium were investigated for their seed oil content. The oil from seeds was extracted by cold extraction technique using chloroform/methanol in 2:1 ratio as solvent. Oil extraction from seeds of Red Clover (Trifolium pratense), Rough Hawkbit (Leontodon hispidus), Cow Parsley (Anthriscus sylvestris), St John’s Wort (Hypericum perforatum), Common Yarrow (Achillea millefollium) and Birdsfoot Trefoil (Lotus corniculatus) plant species was done on wet weight which came out to be 7.89±0.11%, 11.86±0.07%, 14.78±0.31%, 24.20±0.02%, 20.08±0.15% and 7.04±0.12% respectively. The physicochemical properties of the extracted oils were analyzed. Some of these oils can be of great commercial value. [less ▲]

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See detailCan phytoestrogen-rich plants restore the image of livestock in terms of human health? Do they promise a differentiated quality products chain?
Daems, Frédéric ULg; Jasselette, Christophe; Lognay, Georges ULg et al

Poster (2014, February 07)

In a project named PhytoHealth, the development of analytical methods for studying the impact of phytoestrogens rich diet on the «health value» of animal products is in progress. Despite the ambiguous ... [more ▼]

In a project named PhytoHealth, the development of analytical methods for studying the impact of phytoestrogens rich diet on the «health value» of animal products is in progress. Despite the ambiguous image that have phytoestrogens, some of their metabolites seemed to have potentially beneficial effects to human health. In a first time, a microbial metabolite (equol) was selected and its metabolism in dairy cow is studied. A first method using the UPLC®-MS/MS technology has been validated and has achieved a screening of equol content in milk consumed in Wallonia. Equol was found in all milk samples analyzed and a significant difference between farming methods has been highlighted. A second analytical method to quantify the equol precursors was then developed and a study of forage plants consumed by Belgian dairy cows will be conducted to select the richest fodder varieties. Other methods will be developed to better understand the metabolism in the cow and estimate the impact of enriched milk on human health. An original approach involving the use of minipigs will be considered. In the end, creating of a differentiated quality animal products chain could be interesting for the consumer, but also recoverable for the producer. [less ▲]

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See detailFrom wood charcoals to trees: pitfalls and successes of the taxonomic identification in tropical contexts
Morin-Rivat, Julie ULg; De Weerdt, Joëlle; Hubau, Wannes et al

Poster (2014, February 07)

So as to document the past history of tropical forests, several palaeoenvironmental proxies have been used. For instance, charcoals from soil deposits provide a local signal of the evolution of the ... [more ▼]

So as to document the past history of tropical forests, several palaeoenvironmental proxies have been used. For instance, charcoals from soil deposits provide a local signal of the evolution of the vegetation together with snapshots of human interactions with the environment. As charcoal analyses are rare in tropical contexts, here we aim at presenting the different aspects of charcoal studies through their pitfalls and successes as well as the needs for further research. Charcoal analysis (anthracology) is a discipline initially from archaeobotany that consists in the analysis of pieces of charred wood primarily found in archaeological contexts but also in natural soil layers. Its goal is to identified the species that burnt during the past through the observation of the charred wood structure. Indeed carbonization, as the incomplete combustion of the ligneous material, preserves the wood structure. The identifications obtained through microscopic observations allow assessing past uses of wood and human impacts on the forest landscape. However, issues typically tropical exist: difficulties related to fieldwork accessibility, to sampling, to soil processing so as to collect the charcoals, difficulties related to the taxonomic identification because of the huge number of species and of the limited number of anatomical descriptions. New developments are nonetheless emerging for Central Africa with original anatomical descriptions, identification protocols and visual keys. [less ▲]

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See detailPaints based on renewable materials
Olive, Gilles ULg; Richel, Aurore ULg

in BOOK OF SHORT ABSTRACTS - POSTER PRESENTATIONS 19TH NATIONAL SYMPOSIUM ON APPLIED BIOLOGICAL SCIENCES (2014, February 07)

Paints, at the coating meaning, are known since a long time. Typically, paint is a dispersion of one or more powders (pigments and fillers) in a macromolecular substance ("resin"), called film-forming ... [more ▼]

Paints, at the coating meaning, are known since a long time. Typically, paint is a dispersion of one or more powders (pigments and fillers) in a macromolecular substance ("resin"), called film-forming material, diluted in solvents. Pigments are solid particles, used to give opacity and/or color. Today almost all pigments have a synthetic origin. The fillers are often natural compounds. Unlike pigments, fillers have low opacity and are colorless. These very cheap products achieve the required solid content under satisfactory economic conditions. Resins used in paints have the property of forming a continuous solid (hard or flexible) film under specific conditions. They are often called “resins”. They can be solid or liquid at room temperature. The solvents are used to control the viscosity of the paint in order to facilitate its production and application. The solvents used are volatile compounds. Additives are minor compounds (a few percent), whose function is to either promote or prevent some developments of the product. For example, surfactants improve the homogeneity of the dispersion. Some additives protect the film against mold or ultraviolet radiation, or against the formation of free radicals under the action of sunlight. Since the end of the 18th century most of those paints are petroleum-based. But the near disappearance of the petroleum causes a renewed interest in bio-based preparations. In this communication, we present an overview of bio-based alternatives. [less ▲]

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See detailPhysico-chemical properties and aroma profile of Acacia Honey produced in Romania
Madas, Mariana-Niculina ULg; Francis, Frédéric ULg; Marghitas, L.A. et al

in Communications in Agricultural and Applied Biological Sciences (2014, February 07), 79(1), 133-135

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See detailBiodiversity and ecosystem services: think functional!
Uyttenbroeck, Roel ULg; Hatt, Séverin ULg; Paul, Aman ULg et al

Poster (2014, February 07)

During the last years, several studies and reviews have considered the relation between biodiversity and ecosystem functioning or the provision of ecosystem services. Many studies found that plant ... [more ▼]

During the last years, several studies and reviews have considered the relation between biodiversity and ecosystem functioning or the provision of ecosystem services. Many studies found that plant functional traits and plant functional diversity (FD) are key drivers in this relation in terrestrial ecosystems. Researchers used different methods to obtain a gradient in plant FD to examine the effect on ecosystem services, going from observational studies of natural communities to synthetic assemblages. Furthermore, different methods exist to quantify plant FD going from simple functional trait richness to indices, distance-based frameworks and the division into FD components. In the AgricultureIsLife project, we set up a field experiment aiming to examine the biodiversity – ecosystem service relation in agricultural context. The experiment consists of perennial wildflower strips with different plant functional diversities in an arable field with conventional crop production. The wildflower strips were sown as synthetic assemblages but are subject to natural succession during the following years. We monitor the evolution of FD from the sowing to the establishment of a typical wildflower strip using Rhao’s quadratic entropy index to quantify FD. In addition, the flower strips will be monitored for four ecosystem services they are expected to provide: pollination, pest control, biodiversity support and provision of valuable compounds. [less ▲]

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