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See detailEpigenetic mechanisms underlying long-term programming effects of prenatal protein undernutrition by albumen removal in the chicken
Willems, E.; Guerrero-Bosagna, C.; Buyse, J. et al

Poster (2014, April)

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See detailEvaluation of the relationships between characteristics of the vertebral column of different cetaceans and their ecology: A preliminary study.
Gillet, Amandine ULg; Ninane, Catherine ULg; Remy, François ULg et al

Poster (2014, April)

Ecomorphology is the study of the relationships between functional design and the environment. One of its aims is to understand how the environmental factors can constraint the performance of an organism ... [more ▼]

Ecomorphology is the study of the relationships between functional design and the environment. One of its aims is to understand how the environmental factors can constraint the performance of an organism or act on its phenotype. Different studies have already showed in different cetaceans that the number and shape of vertebrae can reflect the stiffness of the body and consequently can impact their swimming mode. The aim of this preliminary study is to establish relationships between characteristics of the vertebral column of different cetaceans and their ecology. To this purpose, we have studied meristic and morphometric data on the vertebrae (centrum length, height and width, neural and haemal spine height and the transverse process length) of different species of mysticetes and odontocetes coming from the Aquarium-Museum of Liège and Royal Institute of Natural Sciences of Bruxelles. Preliminary results showed the distinction of three morphotypes: firstly, the active, cruising, fast swimmers with rigid body, secondly, the maneuverers, slow swimmers with flexible body and thirdly, the steady swimmers. [less ▲]

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See detailFLUSHING PORCINE DCD LIVERS WITH CYCLO-DEXTRIN COMPLEXED CURCUMIN DOES NOT REDUCE ISCHEMIA REPERFUSION INJURY
MEURISSE, Nicolas ULg; PARKINNEN, J; CEULEMANS, L et al

Poster (2014, April)

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See detailIn vitro culture of seal muscle-derived satellite cells
Freichels, Astrid ULg; Baise, Etienne ULg; Jauniaux, Thierry ULg et al

Poster (2014, April)

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See detailThe Neural Correlates of Re-cancellation Behaviors in Unilateral Neglect: A Neuropsychological Approach
Wansard, Murielle ULg; Bastin, Christine ULg; Meulemans, Thierry ULg

Poster (2014, April)

The present study focused on re-cancellation behaviors in unilateral neglect (i.e., the tendency to search repeatedly items located on the right side in visual search tasks), and used a neuropsychological ... [more ▼]

The present study focused on re-cancellation behaviors in unilateral neglect (i.e., the tendency to search repeatedly items located on the right side in visual search tasks), and used a neuropsychological approach to identify the cerebral correlates of this deficit. Fourteen patients suffering from left neglect and 14 elderly age-matched controls performed a cancellation task without visual feedback. Neglect patients cancelled fewer targets than controls, and re-cancelled an abnormally high number of targets. Lesion maps were used to compare the location of brain damage in neglect patients with the highest versus the lowest percentage of re-cancellations. Anatomical data revealed that the right insula is commonly damaged in 5 out of 6 patients with the highest re-cancellation percentage, but is spared in the subgroup of patients with the lowest re-cancellation percentage. These results suggest that damage to the right insula may contribute to pathological visual search in spatial neglect, possibly by reducing interaction between the ventral and dorsal attention network (the latter being more directly involved in spatial processes). [less ▲]

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See detailPolyplexes Targeting Angiogenesis in Cancer
Frère, Antoine ULg; Peixoto, Paul ULg; Kawalec, Michal et al

Poster (2014, April)

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See detailWeb-based application for Data INterpolation Empirical Orthogonal Functions (DINEOF) analysis
Tomazic, Igor ULg; Alvera Azcarate, Aïda ULg; Barth, Alexander ULg et al

Poster (2014, April)

DINEOF (Data INterpolating Empirical Orthogonal Functions) is a powerful tool based on EOF decomposition developed at the University of Liege/GHER for the reconstruction of missing data in satellite ... [more ▼]

DINEOF (Data INterpolating Empirical Orthogonal Functions) is a powerful tool based on EOF decomposition developed at the University of Liege/GHER for the reconstruction of missing data in satellite datasets, as well as for the reduction of noise and detection of outliers. DINEOF is openly available as a series of Fortran routines to be compiled by the user, and as binaries (that can be run directly without any compilation) both for Windows and Linux platforms. In order to facilitate the use of DINEOF and increase the number of interested users, we developed a web-based interface for DINEOF with the necessary parameters available to run high-quality DINEOF analysis. This includes choosing variable within selected dataset, defining a domain, time range, filtering criteria based on available variables in the dataset (e.g. quality flag, satellite zenith angle …) and defining necessary DINEOF parameters. Results, including reconstructed data and calculated EOF modes will be disseminated in NetCDF format using OpenDAP and WMS server allowing easy visualisation and analysis. First, we will include several satellite datasets of sea surface temperature and chlorophyll concentration obtained from MyOcean data centre and already remapped to the regular grid (L3C). Later, based on user’s request, we plan to extend number of datasets available for reconstruction. [less ▲]

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See detailvCCL2, the third agonist ligand for the -arrestin-biased chemokine receptor CXCR7
Szpakowska, Martyna ULg; Derj, Anouar ULg; Counson, Manuel et al

Poster (2014, April)

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See detailTRAPPIST monitoring of comet C/2012 F6 (Lemmon)
Opitom, Cyrielle ULg; Jehin, Emmanuel ULg; Manfroid, Jean ULg et al

Poster (2014, April)

C/2012 F6 (Lemmon) is a long period comet discovered by the Mount Lemmon Survey on 2012 March 23 at 5 AU from the sun. C/2012 F6 (Lemmon) reached perihelion on March 23, 2013 at 0.73 AU from the sun. In ... [more ▼]

C/2012 F6 (Lemmon) is a long period comet discovered by the Mount Lemmon Survey on 2012 March 23 at 5 AU from the sun. C/2012 F6 (Lemmon) reached perihelion on March 23, 2013 at 0.73 AU from the sun. In December 2012 the comet was unexpectedly bright, allowing us to make an extensive monitoring during several months with both broadband and narrowband filters to follow the evolution of the comet chemical composition. The monitoring was made with TRAPPIST robotic telescope installed at La Silla observatory [1]. TRAPPIST is a 60-cm telescope dedicated to the study of exoplanets and small bodies in the solar system. The telescope is equipped with a 2Kx2K FLI Proline CCD camera very sensitive in the blue and the red. A set of narrowband cometary filters designed by the NASA for the Hale-Bopp Observing Campaign [2] is permanently mounted on the telescope along with classic Johnson-Cousins B, V, Rc, and Ic filters. We observed the comet from December 11, 2012 to March 4, 2013 (pre-perihelion) and from April 29, 2013 to June 11, 2013 (post-perihelion). At least 2 or 3 observing runs per week were programmed during this period. We collected 1358 images on 52 nights. In January and February the comet visibility allowed us to make several long runs and to detect the comet rotational variability. From the comet images in narrowband filters we studied the gaseous coma chemical composition and activity by deriving OH, NH, CN, C2 and C3 production rates using a classical Haser model [3]. The production and properties of the dust component were studied through the observation of C/2012 F6 (Lemmon) with narrowband continuum filters at 344.2 nm (UC), 444.9 nm (BC), 525.7 nm (GC) and 713.0 nm (RC). We used A(θ)fρ [4] parameter as a proxy for the dust production. [less ▲]

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See detailChemical analyses of the seeds from Prunella vulgaris: A chemotaxonomic approach
Paul, Aman ULg; Frederich, Michel ULg; Cieckiewicz, Ewa ULg et al

Poster (2014, April)

Common self-heal (Prunella vulgaris) plants are traditionally sown along the border of crops to enhance the biodiversity. Besides enhancing the biodiversity, they can also be a source of interesting ... [more ▼]

Common self-heal (Prunella vulgaris) plants are traditionally sown along the border of crops to enhance the biodiversity. Besides enhancing the biodiversity, they can also be a source of interesting compounds which could be important for food, pharmaceutical and cosmetic industries. The seeds of Common Yarrow were investigated for proteins, fatty acid compositions and polyphenolic compounds. The protein content was analyzed according to Dumas method, the extraction of oil was done using a cold extraction technique employing 2:1 chloroform/methanol as solvent, the fatty acid composition was determined using the gas chromatography and the amount of polyphenolic compounds were estimated using the method as described in European Pharmacopoeia, 8th edition. Common self-heal seeds can be of great commercial importance. [less ▲]

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See detailEARLY ALLOGRAFT DYSFUNCTION DECREASES PATIENT SURVIVAL AFTER LIVER TRANSPLANTATION
MEURISSE, Nicolas ULg; FIEUWS, S; JOCHMANS, I et al

Poster (2014, April)

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See detailLocal ensemble assimilation scheme with global constraints and conservation
Barth, Alexander ULg; Yan, Yajing ULg; Canter, Martin ULg et al

Poster (2014, April)

Ensemble assimilation schemes applied in their original, global formulation have no problem in respecting linear conservation properties if the ensemble perturbations are setup accordingly. For realistic ... [more ▼]

Ensemble assimilation schemes applied in their original, global formulation have no problem in respecting linear conservation properties if the ensemble perturbations are setup accordingly. For realistic ocean systems, only a relatively small number of ensemble members can be calculated. A localization of the ensemble increment is thus necessary to filter out spurious long-range correlations. However, the conservation of the global property will be lost if the assimilation is performed locally since the conservation requires a coupling between model grid points, which is filtered out by the localization. In the ocean, the distribution of observations is highly inhomogeneous. Systematic errors of the observed parts of the ocean state can lead to spurious systematic adjustments of the non-observed part of the ocean state due to data assimilation. As a result, global properties which should be conserved, increase or decrease in long-term simulations. We propose an assimilation scheme (with stochastic or deterministic analysis steps) which is formulated globally (i.e. for the whole state vector) but where spurious long-range correlations can be filtered out. The scheme can thus be used to enforce global conservation properties and non-local observation operators. Both aspects are indeed linked since one can introduce the global conservation as a weak constraint by using a global observation operator. The conserved property becomes thus an observed value. The proposed scheme is tested with the Kuramoto-Sivashinsky model which is conservative. The benefit compared to the traditional covariance localization scheme (with an ad-hoc step enforcing conservation) where observations are assimilated sequentially is shown. The assimilation scheme is suitable to be implemented on parallel computers where the number of available computing cores is a multiple of the ensemble size. [less ▲]

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See detailModelling the Congo basin ecosystems with a dynamic vegetation model
Dury, Marie ULg; Hambuckers, Alain ULg; Trolliet, Franck ULg et al

Poster (2014, April)

The scarcity of field observations in some parts of the world makes difficult a deep understanding of some ecosystems such as humid tropical forests in Central Africa. Therefore, modelling tools are ... [more ▼]

The scarcity of field observations in some parts of the world makes difficult a deep understanding of some ecosystems such as humid tropical forests in Central Africa. Therefore, modelling tools are interesting alternatives to study those regions even if the lack of data often prevents sharp calibration and validation of the model projections. Dynamic vegetation models (DVMs) are process-based models that simulate shifts in potential vegetation and its associated biogeochemical and hydrological cycles in response to climate. Initially run at the global scale, DVMs can be run at any spatial scale provided that climate and soil data are available. In the framework of the BIOSERF project (“Sustainability of tropical forest biodiversity and services under climate and human pressure”), we use and adapt the CARAIB dynamic vegetation model (Dury et al., iForest - Biogeosciences and Forestry, 4:82-99, 2011) to study the Congo basin vegetation dynamics. The field campaigns have notably allowed the refinement of the vegetation representation from plant functional types (PFTs) to individual species through the collection of parameters such as the specific leaf area or the leaf C:N ratio of common tropical tree species and the location of their present-day occurrences from literature and available database. Here, we test the model ability to reproduce the present spatial and temporal variations of carbon stocks (e.g. biomass, soil carbon) and fluxes (e.g. gross and net primary productivities (GPP and NPP), net ecosystem production (NEP)) as well as the observed distribution of the studied species over the Congo basin. In the lack of abundant and long-term measurements, we compare model results with time series of remote sensing products (e.g. vegetation leaf area index (LAI), GPP and NPP). Several sensitivity tests are presented: we assess consecutively the impacts of the level at which the vegetation is simulated (PFTs or species), the spatial resolution and the initial land cover (potential or human-induced). First, we show simulations over the whole Congo basin at a 0.5◦ spatial resolution. Then, we present high-resolution simulations (1 km) carried out over different areas of the Congo basin, notably the DRC part of the WWF Lake Tele – Lake Tumba Landscape. Studied in the BIOSERF project, this area is characterized by a forest-savannah mosaic but also by swamp and flooded forest. In addition, forward transient projections of the model driven with the outputs of about thirty global cli- mate models (GCMs) from the new Coupled Model Intercomparison Project Phase 5 (CMIP5) will permit to outline the likely response of carbon pools to changing climate over the Congo basin during the 21th century. [less ▲]

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See detailA geochemical and petrological study of the Late Cretaceous banatites from the Apuseni Mountains, Romania
Vander Auwera, Jacqueline ULg; Berza, Tudor; Dupont, Alain et al

Poster (2014, April)

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See detailComplex regulation of the FRD3 gene in Arabidopsis relatives
Charlier, Jean Benoit; Polese, Catherine ULg; Nouet, Cécile ULg et al

Poster (2014, March 31)

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See detailGlioma metastatis : a case series and review
REUTER, Gilles ULg; LOMBARD, Arnaud ULg; SCHOLTES, Félix ULg et al

Poster (2014, March 29)

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See detailBiodiversity and utilizations of pearl millet cultivars in hyper-arid regions of Algeria.
Boudries, Nadia; Sindic, Marianne ULg; Belhaneche-Bensamra, Naima et al

Poster (2014, March 27)

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See detailmaking the most of the LBTI nulling interferometry observations using a statistical data reduction method
Marion, Lindsay ULg; Mennesson, Bertrand; Defrère, Denis et al

Poster (2014, March 20)

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See detailLe suivi des enfants nés prématurés ou avec un très petit poids de naissance : le projet CAP48
Mostaert, Anne; Nassogne, Marie-Cécile; Vermeylen, Danièle et al

Poster (2014, March 20)

This poster describes the cohort of very preterm and very low birth weight newborns recruted in the "CAP48" project and anaylses the main reasons for cessation of follow-up.

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See detailContribution à l'amélioration de l'accès à une eau potable de qualité pour les populations de la région nord du Burkina Faso
Some, Issam; Guel, Boubié; Hantson, Anne-Lise et al

Poster (2014, March 19)

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See detailGoro Gheri, un secrétaire au service de l'art
Miesse, Hélène ULg

Poster (2014, March 19)

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See detailArtificial Abelian gauge potentials induced by dipole-dipole interactions between Rydberg atoms
Cesa, Alexandre ULg; Martin, John ULg

Poster (2014, March 19)

We analyze the influence of dipole-dipole interactions between Rydberg atoms on the generation of Abelian artificial gauge potentials and fields. When two Rydberg atoms are driven by a uniform laser field ... [more ▼]

We analyze the influence of dipole-dipole interactions between Rydberg atoms on the generation of Abelian artificial gauge potentials and fields. When two Rydberg atoms are driven by a uniform laser field, we show that the combined atom-atom and atom-field interactions give rise to nonuniform, artificial gauge potentials. We identify the mechanism responsible for the emergence of these gauge potentials. Analytical expressions for the latter indicate that the strongest artificial magnetic fields are reached in the regime intermediate between the dipole blockade regime and the regime in which the atoms are sufficiently far apart such that atom-light interaction dominates over atom-atom interactions. We discuss the differences and similarities of artificial gauge fields originating from resonant dipole-dipole and van der Waals interactions. We also give an estimation of experimentally attainable artificial magnetic fields resulting from this mechanism and we discuss their detection through the deflection of the atomic motion. [less ▲]

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See detailInfluence of dipole-dipole interactions decoherence-free states
Damanet, François ULg; Martin, John ULg

Poster (2014, March 18)

Decoherence, known as the consequence of the coupling of any quan- tum system to its environment, causes information loss in the system and represents a major problem in the physical realization of quan ... [more ▼]

Decoherence, known as the consequence of the coupling of any quan- tum system to its environment, causes information loss in the system and represents a major problem in the physical realization of quan- tum computers [1]. Decoherence-Free States (DFS) are considered as a possible solution to this problem. A set of trapped cold atoms placed in a DFS state will be immune against decoherence due to sponta- neous emission. However, because of dipole-dipole interactions between atoms, induced dephasing effects are likely to destroy the coherence and drive the system out of its DFS [1-2]. In this work, we study nu- merically the dynamics of a set of two-level atoms initially in a DFS with respect to dissipative processes by solving the master equation in- cluding both dissipative dynamics and dipole dipole interactions. We focus our attention on the influence of dipolar coupling on the radiated energy rate and coherence of the system as in [3]. In particular, by av- eraging over many realizations of close randomly distributed atomic positions, we show the formation of a superradiant-like pulse and we study its properties as a function of the dipolar coupling strength. [1] D. A. Lidar & K. B. Whaley, Lectures Notes in Phys., Vol. 622, p83-120, Springer (2003). [2] M. Gross & S. Haroche, Physics reports 93, 301-396 (1982). [3] W. Feng, Y. Li & S. -Y. Zhu, arXiv :1302.0957. (2013). [less ▲]

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See detailEnrichir le lait de vache en équol par la consommation de fourrages prairiaux spécifiques
Franckson, Delphine; Daems, Frédéric ULg; Decruyenaere, Virginie et al

Poster (2014, March 16)

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See detailBringing regenerating tissues to life: the importance of angiogenesis in tissue engineering
Carlier, Aurélie ULg; Van Gastel, Nick; Geris, Liesbet ULg et al

Poster (2014, March 11)

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See detailOn the Identication of Symmetric N-qubit Maximally Entangled States
Baguette, Dorian ULg; Bastin, Thierry ULg; Martin, John ULg

Poster (2014, March 11)

Maximally entangled states can serve as a useful resource in many different contexts. It is therefore important to identify those states. Here we are interested in the identification of maximally ... [more ▼]

Maximally entangled states can serve as a useful resource in many different contexts. It is therefore important to identify those states. Here we are interested in the identification of maximally entangled states in the symmetric subspace of an N-qubit system. By maximally entangled states, we refer to symmetric states characterized by a one qubit reduced density matrix proportional to the identity. These states maximise various entanglement measures [1] such as von Neumann and Meyer-Wallach entropy and are unique up to LU in their SLOCC class [2]. We identify and characterize all maximally entangled symmetric states up to 4 qubits. We provide general conditions for a symmetric state with an arbitrary number of qubits to be maximally entangled and identify families of SLOCC classes which do not contain any maximally entangled states. [1] F. Verstraete, J. Dehaene, B. De Moor, Phys. Rev. A 68, 012103 (2003). [2] G. Gour, N. Wallach, N. J. Phys. 13, 073013 (2011) [less ▲]

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See detailCorsican seagrass detritus: An opportune shelter or a copepod Eldorado?
Mascart, Thibaud ULg; Lepoint, Gilles ULg; Remy, François ULg et al

Poster (2014, March 07)

Seagrass ecosystems are extensive beds of marine flowering plants bordering tropical and temperate coastal regions. They play an important role in maintaining biological productivity and bio-geochemical ... [more ▼]

Seagrass ecosystems are extensive beds of marine flowering plants bordering tropical and temperate coastal regions. They play an important role in maintaining biological productivity and bio-geochemical cycles in the sea and support higher diversity and abundance of fauna in comparison to adjacent non-vegetated areas. The seagrass meadow primary production can be directly consumed through herbivory but the majority of the plant material falls on the sea floor during the autumnal leaf senescence. The leaf litter then degrades within the meadow or accumulates with other micro- and macrophytodetritus to form detritus accumulations on the adjacent non-vegetated sand patches. These exported accumulations are quite dynamic in relation to seafloor geomorphology and local hydrodynamics. Thus, the detritus accumulations are an easily disturbed ephemeral environment with one large influx a year. Consequently the physico-chemical characteristics can change very fast and impact the sheltering capacity and food supply present. Nonetheless, fishes, macrofauna and meiofauna are omnipresent throughout the year. In our study site along the shore of N-W Corsica, Posidonia oceanica seagrass meadows are characterised by substantial detritus accumulations. The present study aimed to analyse the biodiversity of the copepod species communities (Crustacea, Copepoda) in those detritus accumulations. The results showed that the copepod detritus community consisted of a mixture of species that are also found in adjacent habitats (seagrass meadow, sediment, epilithic habitats, water column). Each adjacent habitat is characterised by organisms that are morphologically adapted to the specific features of that habitat. The majority of copepods are epiphytic (order Harpacticoida), that occur typically on seagrass leaves and macroalgae. Other species are planktonic (orders Cyclopoida and Calanoida) and some were benthic (order Harpacticoida), known from the nearby sediment. A minority of the copepod community were parasitic on fish or invertebrate (order Siphonostomatoida). In order to clarify their origin, we assume that passive transport by currents plays a significant role next to the active migration from the anoxic sediments under the detritus. For sure they also reproduce within the detritus packages as we found many nauplii, copepodites and gravid females. The above mentioned suggestions cannot explain such high density of copepods by themselves. Other attraction mechanisms are needed to explain the important amount of planktonic and epiphytic species with good swimming ability, such as higher food accessibility. In the detritus no plant-defence mechanisms are present anymore and a lot of micro-organisms and thus potential food sources are present. Furthermore, the dense detritus package provides shelter and protection from potential predators. Subsequently we may consider the detritus accumulations as a copepod species-specific opportune Eldorado for sheltering, nursing and feeding. [less ▲]

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See detailUsing features of mercury and methylmercury to discriminate contamination profiles between sea bass, Dicentrarchus labrax, populations
Cransveld, Alice ULg; Amouroux, David; Koutrakis, Emmanuil et al

Poster (2014, March 07)

Despite many efforts consented in the last decades, Mercury (Hg) emissions have kept rising worldwide. Currently, anthropogenic inputs dominate Hg emissions to the atmosphere by far, natural releases ... [more ▼]

Despite many efforts consented in the last decades, Mercury (Hg) emissions have kept rising worldwide. Currently, anthropogenic inputs dominate Hg emissions to the atmosphere by far, natural releases accounting only for a 4th of the total. Because Hg has a stable gaseous form (Hg0) with a long residence time in the atmosphere (~1year), both natural and industrially produced Hg can be transported far from point sources. Therefore, many uncertainties remain in our knowledge about Hg biogeochemistry. Our study aims at identifying the different Hg forms found in marine predators in order to discriminate different polluted areas and potential pollution sources. More specifically, we seek to discriminate contaminations of local origins versus contamination of global origins. To achieve this, we are currently studying different sea bass, Dicentrarchus labrax, populations from the Atlantic Ocean and Mediterranean. In muscle, liver, kidney and brain tissues, we analyze total Mercury (THg) and methylmercury (MeHg). We are also testing the discrimination power of Hg's stable isotopes (199Hg, 201Hg and 202Hg). Indeed, recent findings show that Hg isotopes can exhibit both mass-dependent (MDF) and mass-independent fractionation (MIF). This means that Hg isotopes provide two different types of information at once, both on biological cycling of Hg, including bioaccumulation (MDF), and on chemical pathways such as photochemical transformations (MIF). Eventually, we are planning to extend our results with compound specific isotope analysis (CSIA) on the carbon of methylmercury. Preliminary analysis performed on 14 juvenile specimens from the North Sea and the Aegean Sea indicate that THg concentrations are higher in individuals from the North Sea than from Greece. The lack of correlation with size and weight indicate that it is likely linked to a difference in contamination levels between the two areas. MeHg is the predominant form of Hg in muscle, while the same cannot be asserted for liver. Mass dependent isotopic values (δ202Hg), were always higher in muscle than in liver and, for each tissue, values were similar between the two areas. This is probably related to the species distribution and to some internal Hg metabolism. For mass independent isotopic signature (MIF), sea bass from the Aegean Sea had a systematically higher Δ201Hg value than individuals from the North Sea. Thus, mass independent values seem definitely site dependent and might be in agreement with differences in both mercury sources and cycling in the North and Aegean Seas. These preliminary results consequently indicate that Hg isotopes may help to discriminate fish from different areas. This promising outcome must be further confirmed by extending our sampling and will be coupled to other results obtained through CSIA. [less ▲]

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See detailChemical Hydrolysis of Fagus sylvatica Wood: Dilute Acid vs. Alkaline Treatment
Miazek, Krystian ULg; Goffin, Dorothée ULg; Richel, Aurore ULg

Poster (2014, March 05)

Lignocellulosic biomass, found in a large variety of plants such as coniferous trees (Softwood), broad leaved trees (Hardwood), grasses and agricultural or food residues, is the most abundant source of ... [more ▼]

Lignocellulosic biomass, found in a large variety of plants such as coniferous trees (Softwood), broad leaved trees (Hardwood), grasses and agricultural or food residues, is the most abundant source of molecules required for production of biofuels and high value - added products. Lignocellulose is composed of three polymers: cellulose, hemicellulose and lignin. Cellulose is a non-branched polymer consisting of glucoses (hexoses). Hemicellulose is a complex carbohydrate containing pentoses (mainly xyloses in the case of Hardwood, grasses and agricultural wastes) or hexoses (usually mannoses in the case of Softwood) as the main sugars. Lignin is a biopolymer with aromatic alcohols as basic monomeric units. Cellulose chains are arranged in bundles and interlinked with hemicellulose. Lignin is cross-linked with hemicellulose and occupies space between cellulose bundles. Due to complex polymeric structure, lignocellulosic materials are resistant to hydrolysis. A number of treatment methods (mechanical, chemical, biochemical) is implemented to successfully hydrolyse lignocellulose. Amongst chemical methods harnessed to break lignocellulose structure, dilute acid and alkaline treatments are commonly mentioned, as the most efficient ones. The objective of this study was to evaluate the effect of dilute acid and alkaline treatment on hydrolysis rate of polymeric components in Fagus sylvatica wood. Fagus sylvatica also known as common beech is a broad leaved, deciduous tree that belongs to the family of Fagaceae, widely spread in Europe. Beech wood was determined to contain 48 % glucose, 18 % xylose and 20 % Klason lignin in its dry material. Results of this study showed that 1 h hydrolysis at 100 °C with the use of 3 % H2SO4 resulted in 71 % removal of xylose and 4 % removal of glucose with Klason lignin remained intact. Additionally, the presence of sugar degradation products: 2 - furfural and hydroxymethylfurfural was detected in dilute acid hydrolysate. Release of 2 - furfural and hydroxymethylfurfural from beech wood was determined as 0.03 % and 0.1 %, respectively. On the other hand, 1 h hydrolysis at 100 °C with the use of 7 % NaOH caused 59 % xylose removal and 11 % removal of Klason lignin with no effect on glucose. Dilute acid hydrolysis proved to be more efficient in removing xylose, but alkaline hydrolysis additionally showed to remove Klason lignin. [less ▲]

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See detailWildflower strips: a help for crop protection ?
Hatt, Séverin ULg; Uyttenbroeck, Roel ULg; Bodson, Bernard ULg et al

Poster (2014, March 05)

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See detailSome Interesting Sources of Plant Seed Oil
Paul, Aman ULg; Danthine, Sabine ULg; Blecker, Christophe ULg et al

Poster (2014, March 05)

There is a growing realization worldwide that biodiversity is fundamental to agricultural production and food security, as well as a valuable ingredient of environmental conservation. Flowering strips ... [more ▼]

There is a growing realization worldwide that biodiversity is fundamental to agricultural production and food security, as well as a valuable ingredient of environmental conservation. Flowering strips around the border of the crops serves as an important function to improve the biodiversity, besides this they play a major role in the ruminant nutrition and serve as a source of numerous beneficial compounds. It is well known that seeds store their food reserves for next generation mainly in the form of lipids; some of the seeds from these flowering strips could be an interesting source of lipids. These seed oils could play important role in food, pharmaceutical, cosmetics and other industries. The extraction of seed oil from four such plant species in Belgium namely Oregano (Origanum vulgare), Yellow Bedstraw (Galium verum), Common Self-heal (Prunella vulgaris) & Purple loosestrife (Lythrum salicaria) was carried out. Extraction was done by a cold extraction technique using chloroform/methanol in 2:1 ratio as solvent. Amount of oil extracted from Oregano, Yellow Bedstraw, Common Self-heal and Purple loosestrife was 22.58±0.03 %, 3.28±0.01 %, 14.84±0.12 % & 20.32±0.15 %. The fatty acid profiles of these four species were determined by gas chromatography (using methyl esters of their fatty acids); Oleic acid and Linoleic acid were found in all the four species, Gamma-linolenic acid was found in Purple loosestrife & Alpha-linolenic acid was found in Oregano and Common Self-heal plant species. Thermal behaviour of these four plant seed oils were analyzed using Differential Scanning Calorimetry (DSC), while some other physicochemical properties of the seed oils were also analyzed. These plant seed oils can be of great commercial importance. [less ▲]

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See detailUsing active and passive acoustics to assess O2 production of a Posidonia oceanica meadow
Felisberto, P; Zabel, F; Rodriguez, O et al

Poster (2014, March 04)

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See detailL'-band AGPM vector vortex coronagraph's first light on LBTI/LMIRCAM
Defrere, D.; Absil, Olivier ULg; Hinz, P. et al

Poster (2014, March)

We present the first science observations obtained with the L'-band AGPM coronagraph recently installed on LBTI/LMIRCAM. The AGPM (Annular Groove Phase Mask) is a vector vortex coronagraph made from ... [more ▼]

We present the first science observations obtained with the L'-band AGPM coronagraph recently installed on LBTI/LMIRCAM. The AGPM (Annular Groove Phase Mask) is a vector vortex coronagraph made from diamond sub-wavelength gratings tuned to the L'-band. It is designed to improve the sensitivity and dynamic range of high-resolution imaging at very small inner working a [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 detailShergottites: Partial Melts of a Depleted Martian Mantle
Médard, Etienne; Collinet, Max ULg

Poster (2014, March)

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See detailModeling reaction-limited Ostwald ripening of supported Ni catalysts in presence of CO: the role of particle size distribution
Gommes, Cédric ULg; Munnik, Peter; de Jongh, Petra et al

Poster (2014, March)

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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 detailAlkaline Primary Melts from the Primitive Mantle of Mars
Collinet, Max ULg; Médard, Etienne; Vander Auwera, Jacqueline ULg et al

Poster (2014, March)

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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 detailReliability and validity of the Quality of Life Systemic Inventory for Children (QLSI-C): Preliminary result of a modular assessment tool of quality of life using e-Health technologies
Toucheque, Malorie ULg; Etienne, Anne-Marie ULg

Poster (2014, March)

Objective: Use of generic versus specific tools in psychological assessment is a controversial issue. Generic instruments can be used to measure QOL for numerous chronic illnesses; however, they may not ... [more ▼]

Objective: Use of generic versus specific tools in psychological assessment is a controversial issue. Generic instruments can be used to measure QOL for numerous chronic illnesses; however, they may not be sensitive to particular aspects of the disease. Unfortunately, disease-specific measures cannot be used to compare results across diseases or conditions. The QLSI-C is an assessment tool that uses a modular approach developed to overcome these shortcomings. QLSI-C was devised as a generic scale to be integrated with disease specific modules. The purpose of this study is to report on reliability and validity of the QLSI-C generic scale and the cystic fibrosis (CF)-specific module. Methods: QLSI-C was administered to 20 children with CF and 20 healthy children (ages 8-12 years) in Belgium. Internal consistency was assessed using Cronbach’s coefficient. Validity of the QLSI-C was measured using the known-groups method, i.e., analysis of variance (ANOVA) to distinguish between healthy children and children with CF. To examine the validity of the QLSI-C, correlations were calculated between the generic scale and CF-specific module. Results: Internal consistency for the QLSI-C generic scale with the CF-specific module was good ( =.82). ANOVA results revealed a significant difference between CF and healthy children for the QOL score (p=.005), with higher average scores (i.e., lower QoL) for CF children (M=4.35) than healthy children (M=1.25). Correlations between QoL scores on the generic scale and CF-specific module demonstrated medium effect size (r=0.47; p=.04). Conclusions: To date, three specific modules are available for the QLSI-C: (1) cancer; (2) asthma; (3) cystic fibrosis. Originality of this tool is strengthened by use of e-Health technologies (i.e., iPad app for administering the QLSI-C). Satisfactory psychometric properties and state-of-the-art use of technology suggests that the QLSI-C has potential utility for use in clinical trials, research, and clinical practice. [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 detailLearning to learn: Assessment of metacognitive competencies
Frenkel, Stéphanie ULg; Nobile, Debora ULg

Poster (2014, March)

Numerous students are having school difficulties linked to the way they learn. Some authors speak of a “metacognitive deficit”. We refer to a “sleeping potential” instead (Frenkel, 2013, in press; Frenkel ... [more ▼]

Numerous students are having school difficulties linked to the way they learn. Some authors speak of a “metacognitive deficit”. We refer to a “sleeping potential” instead (Frenkel, 2013, in press; Frenkel & Deforge, in press; Frenkel & Nobile, 2013). Be it psychologists, teachers or parents, all wish to develop their skills in order to help these students. This is the case in primary and secondary school. Metacognitive abilities play a central role in learning (e.g., Frenkel & Deforge, in press; Giasson, 2001; Grangeat, 1997; Hessels & Hessels-Schlatter, 2010b; Lumbelli, 2003; Poissant, Poëllhuber & Falardeau, 1994; Rozencwajg, 2003; Veenman, Kok & Blöte, 2005) and thus in successful school learning (Büchel, 2013a, 2013b; Van der Stel & Veenman, 2010; Wang, Haertel & Walberg, 1994). However, studying them requires that we clarify what is meant by “metacognition” and “metacognitive abilities”. In this framework, we developed the EDUCA + project which is intended to provide possible solutions. EDUCA + is based on wide field experience. Its theoretical background is based on a substantial review of the literature. Its objective is to increase the expertise of “front line” field workers by developing specific products such as tools, training courses, services, and a website (Frenkel, in press). This will notably enable them to develop their expertise, detect « sleeping » potential, diagnose, give advice when necessary, intervene (prevention and remediation) and use the tools efficiently. Two types of tools are being designed. On the one hand, assessment tools (tests allowing to put forward the learner’s strengths and weaknesses as well as the scope of his/her “sleeping potential”). On the other hand, intervention tools (short prevention vs. remediation programs). This also includes training courses and services. The creation of a website also aims to reinforce the actions of EDUCA + (personalized access depending on the internaut’s profile: students, parents, professionals). The aim of this paper is to present this research project and its main theoretical background. Keywords: Metacognition, School, Student, Potential, Dynamic Assessment. [less ▲]

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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 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 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 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 detailEffect of encapsulated nanoparticles on thermophillic anaerobic digestion
Al-Ahmad, Alaa Eddin ULg; Hiligsmann, Serge ULg; Lambert, Stéphanie ULg et al

Poster (2014, February 07)

Recently, enormous interest has been focused on biological applications of metal nanoparticles NPs due to their small size, high specified surface and their great potential in application to many science ... [more ▼]

Recently, enormous interest has been focused on biological applications of metal nanoparticles NPs due to their small size, high specified surface and their great potential in application to many science fields. The most studied process concerns zero valent palladium and iron NPs improving anaerobic biodegradation of chlorinated hydrocarbons (Windt et al., 2005). Moreover, investigation carried out in our lab showed that iron NPs encapsulated in silicate matrix may enhance hydrogen production by Clostridium butyricum (Beckers et al., 2013). Nevertheless the influences of metal NPs on methane producing anaerobic digestion have seldom been investigated. The present work investigates the enhancement effect of seven different metal NPs on methane production during the thermophilic anaerobic digestion. NPs of Cu, Pd, Pt, Ni, Co, Ag and Fe encapsulated in porous silica (SiO2) to prevent their coagulation and agglomeration, were added at concentration of 10-5mol/L in batch test (125ml serum bottles containing 70mL culture medium with 5g/L acetate monohydrate as the sole carbon substrate). Nickel, cobalt and iron NPs improved methane production from acetate. To confirm the previous results, the NPs were tested at different concentrations (10-4, 10-5, and 10-6 mol/L) with starch and glucose substrates. The results show that the impact increases with the increase of NPs concentrations up to 10-4 mol/L. The modified Gompertz equation was applied to describe the effect of NPs on anaerobic digestion. According to this model, the kinetic of methane production was particularly affected by nanoparticles addition. The values of the maximum methane production rate MPR (ml/day) was significantly higher 72.5% with nickel NPs at a concentration of 10-4 mol/L than the control without NPs. [less ▲]

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See detailBiofilter in aquaponics
Delaide, Boris ULg; Lambrechts, Paul Emile ULg; Willaert, Jean-François ULg et al

Poster (2014, February 07)

Aquaponics is a combination of aquaculture (fish farming) and hydroponics (horticulture). In this concept, the fish faeces and excreted ammonia are partially transformed into soluble nutrients which then ... [more ▼]

Aquaponics is a combination of aquaculture (fish farming) and hydroponics (horticulture). In this concept, the fish faeces and excreted ammonia are partially transformed into soluble nutrients which then are available for plants. Wastewater from aquaculture is filtrated by plants and return to the fish tank in a loop cycle. This strongly reduces the use of water and increases the economic efficiency with an additional production of plant, e.g. vegetables. From the hydroponics view, this combination allows important decreases in chemical nutrients use for plant grow. A central part of this system is the biofilter. The microorganisms that colonize it are essential to process the fish waste into soluble nutrients easily assimilated by plants. During this process, nitrifying bacteria convert free ammonia into nitrite and then nitrate. The first objective of this research will concern the identification and isolation of the main microorganism species involved by the dilution plating and metagenomics technics. The optimal conditions to process the fish waste will be determined for such microorganism. The efficiency of nitrite and nitrate production by these micro-organisms will be tested in different conditions (T°, pH, O2, water flow, support, etc..) in vitro at the lab scale and in aquaponics prototypes. [less ▲]

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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)

Detailed reference viewed: 38 (2 ULg)
See detailSimulations of a beta amphiphilic peptide as potential surfactant of membrane proteins
Crowet, Jean-Marc ULg; Dony, Nicolas ULg; Deschamps, Antoine et al

Poster (2014, February 07)

The peptide studied here was designed to form beta amphiphilic films with the aim to stabilize purified membrane proteins. This interaction has notably been followed by FRET. Hydrophobic and hydrophilic ... [more ▼]

The peptide studied here was designed to form beta amphiphilic films with the aim to stabilize purified membrane proteins. This interaction has notably been followed by FRET. Hydrophobic and hydrophilic residues are alternate and positively and negatively charged residues place respectively at the start end the end of the peptide. The peptide has been studied by atomistic and coarse grained molecular dynamics in water, chloroform and mixed solutions. The peptide was observed to spontaniously form beta films at the chloroform water interface. Moreover, when we simulate the interaction of this peptide with a membrane protein and with a membrane protein in a micelle of dodecylphosphocholine. The peptide was observed to form beta films at the membrane protein surface and even remove surfactants from the membrane protein surface. The simulations confirms the behaviour of this peptide observed in vitro and shows that it could be used instead of detergents. [less ▲]

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See detailProfiles of the volatile organic compounds emitted by the masses of Abies nordmanniana somatic embryos at maintenance and maturation stages
Druart, Philippe; Michels, Franck ULg; Misson, Jean-Pierre et al

Poster (2014, February 07)

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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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Peer Reviewed
See detailInteractions of a potential plant elicitor mannolipid with plant model membranes
Polo Lozano, Damien ULg; Lins, Laurence ULg; Ongena, Marc ULg et al

Poster (2014, February 07)

The use of chemical pesticides causes problems for human health and environment. In this context, there is an increasing interest for alternative products such as biopesticides. Among them, elicitors act ... [more ▼]

The use of chemical pesticides causes problems for human health and environment. In this context, there is an increasing interest for alternative products such as biopesticides. Among them, elicitors act on the plants by inducing systemic resistance against diseases caused by fungal, viral, bacterial agents and insects. The target of the elicitors is supposed to be the plant plasma membranes (PPM). The main mechanisms of interaction of many elicitors involve proteic receptors but lipid-based elicitors (LBE) may preferably interact with the lipidic fractions of PPM. However there is no detailed information at the molecular level on the PPM-LBE interactions. Our work is focused on a original synthetic LBE composed of a mannoside linked to a myristic acid. It has potential elicitor activities as shown by the assays on tobacco root cells. These activities could be related to its interaction with the lipidic phase of PPM. Since PPM are complex entities, the analyses of the PPM- molecule interactions are quite difficult. In this context, these interactions were carried out using biomimetic membranes of PPM such as Langmuir monolayers and multilayers. The effects of our molecule on these membranar systems were investigated by biophysical and in silico approaches. [less ▲]

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See detailRobot weed killers - no pain more gain
Krishna Moorthy Parvathi, Sruthi Moorthy ULg; Mercatoris, Benoît ULg; Boigelot, Bernard ULg

Poster (2014, February 07)

Weed destruction plays a significant role in crop production, and its automation has both economic and environmental benefits by minimizing the usage of chemicals in the fields. Our aim is to design a ... [more ▼]

Weed destruction plays a significant role in crop production, and its automation has both economic and environmental benefits by minimizing the usage of chemicals in the fields. Our aim is to design a small low-cost versatile robot allowing the destruction of weeds that lie between the crop rows by navigating in the field autonomously. Major challenges foreseen are: mapping the unknown geometry of the field, high-level planning of efficient and complete coverage of the field, and controlling the low-level operations of the robot. Traditionally, sensors like odometer have been used for localisation of robots but without much success in real-world scenarios. Specialized sensors like cameras will therefore be investigated and the plethora of image recognition algorithms will be explored and fine-tuned to enable Simultaneous Localisation And Mapping (SLAM) even on resource constrained robotic platforms. Vision-based localisation is not always viable because of the varying weather conditions of the environment and to overcome that, intelligent stochastic data fusion and machine learning algorithms will be utilized to combine data from heterogenous sensor. The image sensors for localisation will be re-used to differentiate crop rows from the weeds, which are cut when they grow. Finally, logics and reinforcement learning techniques will be explored, to exploit the generated map of the field and other sensorial information, to efficiently plan and execute weed elimination. [less ▲]

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See detailUse of GC-MS in SIM-Scan mode for a selective quantification of polluting volatile organic compounds (VOC) in food industries
Eloundou Mballa, Pierre ULg; DETHIER, Bérénice ULg; Fauconnier, Marie-Laure ULg

Poster (2014, February 07)

The control of atmospheric emission discharges by food industries is classically achieved in two phases. The first one consists of sampling the target atmosphere followed by concentrating the volatile ... [more ▼]

The control of atmospheric emission discharges by food industries is classically achieved in two phases. The first one consists of sampling the target atmosphere followed by concentrating the volatile organic compounds (VOC) contained in a defined volume of this atmosphere on an adsorbing agent. These compounds are then thermally desorbed (TD) or desorbed with a solvent. In the second phase, the gas phase chromatogram (GC) will be coupled with mass spectrometry (MS) or flame ionization detector (FID) for compounds analysis. Quantitative analysis are usually achieved with solvent desorption followed by GC-FID. However, this mode imposes the dilution of the sample by a solvent and consequently may cause high detection thresholds as well as important matrix effect and possible interferences due to chemical reactions between analytes and the solvent. Besides, a preliminary qualitative analysis (GC-MS identification) is necessary. Combining TD-GC-MS allows very low detection thresholds to be reached, and the matrix effect and the interferences caused by products of the reactions between analytes and the solvent to be eliminated. The use of this combination in selected ion monitoring (SIM) mode allows targeting analytes via their characteristic ions, increasing their sensitivity and repeatability insuring more accuracy for simultaneous qualitative and quantitative analysis. This technique was experimented for seeking VOC in the atmosphere around food industries. [less ▲]

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See detailUse of on-line flow cytometry for the characterization of microbial stress dynamics during the bioprocess
Brognaux, Alison ULg; Han, Shanshan; Sorensen, Soren et al

Poster (2014, February 07)

Detailed reference viewed: 13 (1 ULg)
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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 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 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 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 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 detailInteractions between new phenolic glycolipids and model membrane
Sainvitu, Pauline ULg; Nasir, Mehmet Nail ULg; Crowet, Jean-Marc ULg et al

Poster (2014, February 07)

Model membrane based on phospholipids (PL) layers are useful to mimic properties of plasma membranes. The interactions between new synthesized phenolic glycolipids (PGL) and biological membrane are ... [more ▼]

Model membrane based on phospholipids (PL) layers are useful to mimic properties of plasma membranes. The interactions between new synthesized phenolic glycolipids (PGL) and biological membrane are crucial to determine their potential as drug candidates and their cytotoxicity . [less ▲]

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See detailThree aspects, One concept: Agroecology. Agroecological practices and human interactions for a new approach for science. An example at the Univeristy of Liege.
Hatt, Séverin ULg; Artru, Sidonie ULg; Boeraeve, Fanny ULg et al

Poster (2014, February 07)

Critics are raising about conventional farming and its consequences on biodiversity, human health and society. As alternatives, novel models for agriculture are proposed, and among them Agroecology. Quite ... [more ▼]

Critics are raising about conventional farming and its consequences on biodiversity, human health and society. As alternatives, novel models for agriculture are proposed, and among them Agroecology. Quite often, Agroecology is seen as the application of ecological knowledge to the agricultural production. Indeed, this helps to develop more ecological farming practices favoring biodiversity to provide ecosystem services at multiple scales. Agroecology goes further in considering that the agricultural production is integrated in a food system guided by human interactions. This latter one takes into account socio-economic and political dimensions to develop new production systems. Doing so, it assures food security worldwide while preserving resources for future generations. Facing these ambitious objectives, academics are invited to elaborate a new approach for science in developing participatory and action-oriented approaches as well as multidisciplinarity. AgricultureIsLife is a research platform built up at the University of Liège (ULg). In 2013, 40 researchers (including 18 young researchers) from 16 research units of ULg were working in a multidisciplinary approach. About twenty research topics have been divided in four research axes of which objectives are to develop a more sustainable agriculture. The platform has the ambition to discuss its results to a large comity gathering the actors of the agricultural development. The aim of our work is firstly to present Agrocology as a concept made of three interrelated aspects. To illustrate it, the organization and objectives of the research platform AgricultureIsLife will be discussed in a second part. [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 detailQuantitative gas chromatography - mass spectrometry profiling of volatile organic compounds produced by barley (Hordeum distichon L.) roots according to plant age
Delory, Benjamin ULg; Delaplace, Pierre ULg; du Jardin, Patrick ULg et al

Poster (2014, February 07)

In chemical ecology, the roles played by root-emitted volatile organic compounds (VOCs) in biotic interactions and the quantitative analysis of such chemicals in root tissues remain poorly documented. In ... [more ▼]

In chemical ecology, the roles played by root-emitted volatile organic compounds (VOCs) in biotic interactions and the quantitative analysis of such chemicals in root tissues remain poorly documented. In this context, this study aims at developing a fully automated analytical methodology allowing both identification and accurate quantification of VOCs produced by roots of a monocotyledon plant species. Briefly, VOC emitted by crushed barley roots are successively trapped by dynamic headspace sampling on Tenax TA adsorbents, thermally desorbed and cryofocused, separated by gas chromatography (GC) and finally analysed by mass spectrometry (MS) in both SCAN and selected ion monitoring modes. Results show that barley roots mainly produce four volatile aldehydes, namely hexanal, (E)-hex-2-enal, (E)-non-2-enal and (E,Z)-nona-2,6-dienal. These molecules are well-known linoleic (C18:2) and linolenic (C18:3) acid derivatives produced via the lipoxygenase and the hydroperoxide lyase pathways of higher plants. Our findings contrast with analyses documented on aboveground barley tissues that mainly emit C6 aldehydes, alcohols and their derivative esters. Moreover, preliminary results indicate quantitative changes in the volatile profile contained in barley roots according to plant age. Multivariate statistical analyses are currently underway to quantitatively assess these changes using plants at five selected developmental stages ranging from germination to the end of tillering. [less ▲]

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See detailScreening of two agricultural genomic DNA libraries to seek new glycoside hydrolases
Stroobants, Aurore ULg; Portetelle, Daniel ULg; Vandenbol, Micheline ULg

Poster (2014, February 07)

Soils are very rich environments where the diversity of microorganisms is very high. These microorganisms play an important role in the degradation of organic matter with enzymes able to degrade it. This ... [more ▼]

Soils are very rich environments where the diversity of microorganisms is very high. These microorganisms play an important role in the degradation of organic matter with enzymes able to degrade it. This work aims to discover, by functional screening, new microbial glycoside hydrolases from soils collected in winter and spring in a winter wheat crop. The genomic DNA was extracted from both soils to construct two libraries in Escherichia coli. These libraries were then screened for beta-glucosidase activities on 2YT agar media containing 0.5% esculin and 0.1% ammonium iron (III) citrate. At this time, about 250.000 clones from each library have been screened. Two beta-glucosidases have already been found in the winter library while five beta-glucosidases and two glycosyltransferases were identified in the spring library. Sequence analyses with the BLASTX program revealed putative enzymes showing between 25% and 72% sequence identity with known enzymes and belonging to three glycoside hydrolase families (GH1, GH3 and GH20) and to two probably new glycosyltransferase families. Biochemical characterisation of the candidates at several pH values and temperatures, and with four substrates, is in progress. [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 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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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 detailIntegrated farming systems in Kinshasa (DRC) Diversity of agricultural practices
Mafwila Kinkela, Patrick ULg; Bindelle, Jérôme ULg; WILLEMS, E, Emilie et al

Poster (2014, February 07)

In Kinshasa in the Democratic Republic of Congo, integrated farming of livestock and fish farming is little documented while it is an interesting way of ecological intensification systems. After ... [more ▼]

In Kinshasa in the Democratic Republic of Congo, integrated farming of livestock and fish farming is little documented while it is an interesting way of ecological intensification systems. After identifying the density of fish ponds in the territory of the city using satellite images, about 200 farms with at least one pond and located in 2 in peri-urban and rural areas were surveyed to characterize the practical integration of the agricultural system. The preliminary results in one of the valleys indicate that the practice of agriculture in synergy with the pig and fish farming is a common practice although flow of components are still insufficiently integrated and some of them are not optimized . The fish - pig farming associations with or without vegetable production are 44 % of the sample. The identification of flow on farms showed that the manure of pigs is mainly used for crops (51%) or sold (28%), while a small part is used to fertilize the ponds. This may be explained by the predominant share of income (67%) devoted to vegetable production while sludge of ponds is rarely used to fertilize area of vegetable production. Residues of vegetable crops are rarely used to feed pigs and fish because of their limited availability. Feeding pigs and fish is based primarily on agro-industrial by-products such as wheat bran (81%) and the spent brewery grains (62%) and forages (62%). The presentation will analyze the results obtained in the three sites visited and outline opportunities for improvement. [less ▲]

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See detailEstimating daily yield and content of major fatty acids from single milking
Arnould, Valérie ULg; Reding, Romain; Delvaux, Charles et al

Poster (2014, February 07)

Reducing the frequency of milk recording and the number of recorded samples per test-day could be a solution in order to reduce costs of official milk recording. However, fewer samples lead to a decrease ... [more ▼]

Reducing the frequency of milk recording and the number of recorded samples per test-day could be a solution in order to reduce costs of official milk recording. However, fewer samples lead to a decrease in the accuracy of predicted daily yields. Unfortunately, the current published equations use the milking interval that is often not available and/or reliable in practice. The first objective of this study was to propose models using easily available traits. Therefore the milking interval was replaced by a combination of data easily recorded by milk recording. The second objective of this study was to enlarge the previous investigations to milk fatty acids (FA) in order to propose a practical method for estimating accurate daily milk, fat and major FA yields from single milking. The fit goodness of proposed models was evaluated based on the correlation values between the estimated and observed daily yields in addition to the calculation of the mean square error. Obtained results are promising. Correlation values were comprised between 96.4% and 97.6% when daily yield were estimated from morning milking, and from 96.9% to 98.3% when daily yield were estimated from evening milking. The combination of records related to lactation stage, month of test, milk yield, and fat could replace the milking interval effect. Because of their simplicity, proposed models would be easy to implement. [less ▲]

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See detailIs the noxious Ambrosia artemisiifolia L. going to invade Belgium?
Ortmans, William ULg; Chauvel, Bruno; Mahy, Grégory ULg et al

Poster (2014, February 07)

Ambrosia artemisiifolia L. is an invasive species from North America, causing a health crisis in Europe due to its highly allergenic pollen. In France, there is a zone where the A. artemisiifolia ... [more ▼]

Ambrosia artemisiifolia L. is an invasive species from North America, causing a health crisis in Europe due to its highly allergenic pollen. In France, there is a zone where the A. artemisiifolia populations are naturalized and invasive. Outside this area, populations are more rare and do not seem to expand. We tested if the performances of A. artemisiifolia are varying with competition level, and among geographical zones. The results show that populations from Belgium and Netherlands are not less efficient than invasive populations for the measured traits. [less ▲]

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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 detailIs the behaviour of grazing cattle influenced by the presence of a hedge in the pasture?
Vandermeulen, Sophie ULg; Yando, Emile; Marche, Christian et al

Poster (2014, February 07)

The interest in using shrubs and trees as forage for cattle is raising in temperate regions, along with the environmental measures promoting hedges along pasture. This study aimed at determining the ... [more ▼]

The interest in using shrubs and trees as forage for cattle is raising in temperate regions, along with the environmental measures promoting hedges along pasture. This study aimed at determining the influence of the presence of a woody hedge on grazing cattle behavior as well as the evolution of this behavior during the grazing season. Twelve heifers were set to graze a standard ryegrass and clover meadow during the grazing season of 2013. The animals were divided in 2 groups : one with a free access to a hedge composed by 10 temperate shrub and tree species, the other with no access to a hedge (control). Their behavior (grazing, browsing and other activities) was monitored during 14h d-1 replicated 3d week-1 during 3 periods (May, July and September). Results suggest that both season and presence of a hedge have an influence on the behavior of heifers. Grazing, resting and rumination varied between the two groups in each period (P<0.05). The time spent browsing was influenced by the season (P<0.001); the heifers with an access to the hedge could browse 19.3% of the total time in May against 5.9 and 5.4% in July and September. Both control and experimental heifers grazed more with the progressing season, but the animals without the hedge grazed always more than the heifers that could graze and browse (49.6 vs 43.0%). In conclusion, browsing woody species represents a significant part of the time spent for forage ingestion, and variation in this behavior over the whole grazing season requires to investigate the influence of both pasture and browse availability and composition. [less ▲]

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See detailIncrease in Soil Macroporosity managed with Winter Ploughing - a preliminary results
Parvin, Nargish ULg; Chelin, Marie ULg; Hiel, Marie-Pierre ULg et al

Poster (2014, February 07)

Measurement of soil water retention capacity by the conventional pressure plate technique always gives a substantial view of soil porosity distribution. The structural orientation is observed in the ... [more ▼]

Measurement of soil water retention capacity by the conventional pressure plate technique always gives a substantial view of soil porosity distribution. The structural orientation is observed in the beginning (higher water retention at 9.8 to 98 hPa water head pressure indicates greater proportion of macroporosity) of the soil moisture characteristic curve obtained from the water retention measurement. Since, tillage practices generally increase soil porosity, the correlation between soil hydraulics and porosity distribution would expect to be different for different tillage systems. In general, macroporosity increase with the adoption of conservative tillage or no tillage system but the changes can be varied with the seasonal variation. In our study, winter ploughing retains more water at the range of 9.8 to 98 hPa than Strip tillage, No-till residues in and No-till residues out. So, we can conclude that there is certainly increase in macroporosity in ploughing than other conservation practices of reduced tillage and no tillage. [less ▲]

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