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See detailGeneric results in Denjoy-Carleman classes
Esser, Céline ULg

Poster (2013, September 09)

Denjoy-Carleman classes are spaces of smooth functions which satisfy growth conditions on their derivatives. We distinguish the class of ultradi fferentiable functions of Roumieu type and the class of ... [more ▼]

Denjoy-Carleman classes are spaces of smooth functions which satisfy growth conditions on their derivatives. We distinguish the class of ultradi fferentiable functions of Roumieu type and the class of ultradi fferentiable functions of Beurling typ. Endowed with its natural topology, the Beurling class is a Fr échet space. In the poster, we give a condition to have the strict inclusion of a Roumieu class into aBeurling class. We obtain then generic results about the set of functions of a Beurling class which are nowhere in a Roumieu class. Those generic results are obtained from three di fferent points of view: using the Baire category theorem, the notion of prevalence and the notion of lineability. We also study the particular case of Gevrey classes. [less ▲]

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See detailFree Group and Recognizability
Raskin, Julien ULg

Poster (2013, September 09)

It is well known that recognizability has many algebraic properties. For example, a subset $L$ of the free monoid $\Sigma^*$ is recognizable if and only if there exists a finite monoid $M$, a subset $P ... [more ▼]

It is well known that recognizability has many algebraic properties. For example, a subset $L$ of the free monoid $\Sigma^*$ is recognizable if and only if there exists a finite monoid $M$, a subset $P$ of $M$ and a morphism $f : \Sigma^* \to M$ such that $L = f^{-1}(P)$. These properties allow us to easily define a concept of recognizability in non-free monoids or even in other algebraic structures, such as groups. Our aim is to study the recognizable subsets of the free group $F_X$ generated by $X$. A classical construction of the latter shows that it can be seen as a subset of the free monoid $(X \cup X')^*$, where $X'$ is a set of formal inverses of elements of $X$, endowed with an ad hoc operation. When $X$ is finite, it appears that $F_X$ is a recognizable language of this monoid. It is then natural to wonder if there is a link between recognizability in $F_X$ and recognizability in $(X \cup X')^*$. We show that every recognizable language of $F_X$ is recognizable in $(X \cup X')^*$, and that we can define a class of automata that recognize the recognizable languages of $F_X$. [less ▲]

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See detailLinear formulation of identifying cdes in graphs
Vandomme, Elise ULg; Gravier, Sylvain; Parreau, Aline ULg

Poster (2013, September 09)

Identifying codes were introduced by Karpovsky, Chakrabarty and Levitin in 1998 and can be applied to locate fire in a building using sensors. Buildings are modelled by graphs with rooms as vertices. The ... [more ▼]

Identifying codes were introduced by Karpovsky, Chakrabarty and Levitin in 1998 and can be applied to locate fire in a building using sensors. Buildings are modelled by graphs with rooms as vertices. The placement of sensors in the rooms corresponds to choosing a subset of vertices. Finding a sensor-placement such that the location of a fire in one room can be precisely determined is equivalent to constructing an identifying code in the graph. These are dominating sets of vertices for which the closed neighbourhood of each vertex (i.e., the vertex and its neighbours) has a unique intersection with the set. The problem of finding an identifying code has been widely studied. Yet its formulation as an integer linear problem hasn't been much considered. Let G be a graph with vertex set V, to an identifying code $C\subseteq V$ of $G$ correspond weights x_u (x_u is 1 if u belongs to C, otherwise x_u is 0) satisfying the following : for all vertices u,v * the sum of the x_w for w in the closed neighbourhood of u is at least 1 * the sum of the x_w for w in the symmetric difference of the closed neighbourhoods of u and v is at least 1. Of course, it is interesting to find an identifying code with the smallest possible cardinality. But in general this is a NP-hard problem. A way to obtain bounds on the minimal cardinality is to consider the associated linear problem where the weights x_u are fractional. In the case of vertex-transitive graphs, the minimal cardinality for the fractional case can only take two values which depend on the number of vertices, the degree of the graph and the smallest symmetric difference between any two closed neighbourhoods. We show that for an infinite family of graphs the bound is tight and for another another the bound is far too be reached. [less ▲]

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See detailSensitivity of the CaCO3 content of marine sediments to the kinetic expression of CaCO3 dissolution
Schneider, Birgit; Munhoven, Guy ULg; Regenberg, Anke

Poster (2013, September 05)

The preservation of calcite in marine sediments depends on the CaCO3 saturation state of the ambient pore waters and - to a lesser degree - of overlying seawater. A simple sensitivity analysis shows that ... [more ▼]

The preservation of calcite in marine sediments depends on the CaCO3 saturation state of the ambient pore waters and - to a lesser degree - of overlying seawater. A simple sensitivity analysis shows that the two common expressions to quantify the saturation of seawater with respect to CaCO3 (ΔCO3 =[CO3 ]-[CO3 ]sat , Ω = [CO3 ]/[CO3 ]sat ), when used for the calculation of the time dependent rate of CaCO3 dissolution either in the water column or in the sediments, yield very different rates of CaCO3 dissolution. With the help of an ocean biogeochemical model it was found that different kinetic expressions for pelagic CaCO3 dissolution in an ocean acidification scenario result in a wide range of surface to mid-depth calcite fluxes in the open ocean, which has strong implications for particle ballasting, the flux of calcite to the sediments and finally the global carbon cycle. In the present study we employ a marine sediment model that is fed by calcite and other biogeochemical fluxes from the ocean biogeochemical model using different realizations of calcite dissolution kinetics under (1) preindustrial and (2) last glacial maximum background climate conditions to assess the model-data agreement of the calcite content of deep sea sediments. A better understanding of the mechanisms driving calcite dissolution in the ocean is important to assess the time scale of calcite compensation, for example during glacial-interglacial cycles, but also in future greenhouse scenarios. [less ▲]

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See detailThe experience of chronic illness and psychoptathology across life stories : the case of haemophilic boys and depressive hospitalized adolescents
Jadin, Aurore ULg; Gauthier, Jean-Marie ULg; Boulard, Aurore ULg

Poster (2013, September 04)

The aim of this study is to examine and compare how hemophilic adolescents and depressive hospitalized adolescents tell their own stories, how they build their identities in spite of the treatment ... [more ▼]

The aim of this study is to examine and compare how hemophilic adolescents and depressive hospitalized adolescents tell their own stories, how they build their identities in spite of the treatment constraints and how they involve themselves in different relationships. During an individual semi-structured interview, based on Mc Adams’ works, each teenager’s narrative was collected. Various measurements were taken. The discursive analysis and software were used to analyze the data base. First results show hemophilic boys speak about their disease spontaneously but they don’t identify only to it while depressive hospitalized adolescents define themselves exclusively by their mental disorder. Another report is that, opposed to depressive hospitalized adolescents, hemophilic boys invest hobbies, relationships with peers’ as much as non depressive adolescents even if those can feel different and sometimes restrained. [less ▲]

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See detailHighly non-classical symmetric states of an N-qubit system
Baguette, Dorian ULg; Martin, John ULg

Poster (2013, September 02)

In this work, we consider two measures of non-classicality for pure symmetric N-qubit states : Wehrl entropy (S) and Wehrl participation ratio (R). Measures of non-classicality help to the understanding ... [more ▼]

In this work, we consider two measures of non-classicality for pure symmetric N-qubit states : Wehrl entropy (S) and Wehrl participation ratio (R). Measures of non-classicality help to the understanding of the mechanisms responsible for the transition from quantum to classical physics and are usefull in the context of information processing and quantum-enhanced measurements. [less ▲]

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See detailInfluence of dipole-dipole interactions on superradiance
Damanet, François ULg; Martin, John ULg

Poster (2013, September 02)

Superradiance, known as the cooperative spontaneous emission of a directional light pulse by excited atoms placed in vacuum, has recently regained attention in the context of photon localization [1] and ... [more ▼]

Superradiance, known as the cooperative spontaneous emission of a directional light pulse by excited atoms placed in vacuum, has recently regained attention in the context of photon localization [1] and single photon cooperative emission [2]. The dissipative dynamics of the atoms is known to depend dramatically on the ratio between the typical inter- atomic distance and the atomic transition wavelength, notably because of dipole-dipole interactions [3]. In this work, we study the effects of these interactions on superradiance as in [4] by solving numerically the corresponding master equation. In particular, by averaging over many realizations of the randomly distributed atomic positions, we show that the decay of the radiated energy pulse height with the intensity of the dipolar coupling follows a power law. [1] E. Ackermans, A. Gero & R. Kaiser, Phys. Rev. Lett. 101, 103602 (2008). [2] R. Friedberg & J. T. Manassah, J. Phys. B 43, 035501 (2010). [3] M. Gross & S. Haroche, Physics reports 93, 301-396 (1982). [4] B. Coffey & R. Friedberg, Phys. Rev. A 17, 1033 (1978). [less ▲]

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See detailHepatitis E virus infection in wild boars and humans in Belgium
Thiry, Damien ULg; Mauroy, Axel ULg; Saegerman, Claude ULg et al

Poster (2013, September)

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See detailOptimal conception of a post-combustion CO2 capture unit with assessment of solvent degradation
Léonard, Grégoire ULg; Toye, Dominique ULg; Heyen, Georges ULg

Poster (2013, September)

Solvent degradation may be a major drawback for the large-scale implementation of post-combustion CO2 capture due to amine consumption and emission of degradation products. A kinetics model describing ... [more ▼]

Solvent degradation may be a major drawback for the large-scale implementation of post-combustion CO2 capture due to amine consumption and emission of degradation products. A kinetics model describing solvent oxidative and thermal degradation has been developed based on experimental results. This model has been included into a global Aspen Plus model of the CO2 capture process, so that optimal operating conditions can be identified to minimize both energy and environmental impacts of the process. [less ▲]

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See detailCattle methane fluxes measurement over an intensively grazed grassland using eddy covariance
Dumortier, Pierre ULg; Aubinet, Marc ULg; Beckers, Yves ULg et al

Poster (2013, September)

Methane emissions account for 8% of the EU-15 GHG emissions and livestock generates approximately half of these emissions (European Commission, 2009). Recent technological advances in spectroscopy now ... [more ▼]

Methane emissions account for 8% of the EU-15 GHG emissions and livestock generates approximately half of these emissions (European Commission, 2009). Recent technological advances in spectroscopy now permit methane flux measurement using eddy covariance. This method has numerous strengths. It can measure fluxes in situ, continuously and across broad areas. This provides information about meadow and cattle emission behaviour throughout the year and across a broad range of climatic conditions. We will present here a one year monitoring of methane exchange between an intensively grazed meadow and the atmosphere obtained using the eddy-covariance method. Methane fluxes exchanged by a grazed meadow were measured continuously since June 2012 at the Dorinne Terrestrial Observatory (50˚ 18’ 44” N; 4˚ 58’ 07” E; 248 m asl.) in Belgium. The site is an intensively pastured meadow of 4.2 ha managed according to the regional common practices where up to 30 Belgian Blue cows are grazing simultaneously. Flux measurements were made with the eddy covariance technique, using a fast CH4 analyzer (Picarro G2311-f) and a sonic anemometer (Campbell Csat3). Carbon dioxide fluxes and various micro-meteorological and soil variables, biomass growth and stocking rate evolution were also measured at the site. Turbulent fluxes were calculated according to standard eddy covariance computation schemes and were filtered for non-stationarity and for low friction velocity (u*) events. During grazing periods, fluxes are dominated by the enteric fermentation source and average 111 nmol m-2 s-1. They are highly variable, probably due to cow movements in and out the measurement footprint and cow digestion rhythm. Despite this spread, a daily emission rhythm is observed with higher emissions during the afternoon. When fluxes are integrated over large periods, methane emissions were found strongly related to cattle stocking rate with a slope of 7.34±0.78 mol CH4 day-1 LSU-1. Further developments are ongoing in order to improve cattle geo-localization through infra-red cameras and individual home-made GPS devices. The two systems will be compared in terms of cost, efficiency and ease of use. During cow-free periods, the methane flux averages 10.5 nmol m-2 s-1 and is highly variable with some production peaks above 100 nmol m-2 s-1. No relation was found between methane fluxes and soil temperature while a weak negative relation was found between methane fluxes and soil humidity. No soil methane absorption has been observed. European Commission. Fifth National Communication from the European Community Under the UN Framework Convention on Climate Change (UNFCCC). Technical Report - 2009 – 038 (2009). [less ▲]

Detailed reference viewed: 64 (14 ULg)
See detailMultifractality of quantum wave functions
Dubertrand, Rémy; Garcia-Mata, Ignacio; Georgeot, Bertrand et al

Poster (2013, September)

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See detailHETEROGENOUS CLINICAL AND LABORATORY PRESENTATIONS IN MAD DEFICIENCY
BOEMER, François ULg; SCHOOS, Roland ULg; ACQUAVIVA, Cécile et al

Poster (2013, September)

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See detailThe Upper Paleolithic of the Ikh Tulberin Gol (Northern Mongolia): new excavation at the Tolbor 16 site
Zwyns, N.; Gladyshev, S.A.; Gunchinsuren, B. et al

Poster (2013, September)

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See detailDisruption in energy metabolism and mitochondrial function in a cellular model of inflammation-induced acute kidney injury
Quoilin, Caroline ULg; Mouithys-Mickalad, Ange ULg; Lécart, Sandrine et al

Poster (2013, September)

Sepsis is a very complex clinical condition characterized by stimulation of a systemic inflammatory response due to an infection. It has a profound deleterious effect on kidney functions leading to sepsis ... [more ▼]

Sepsis is a very complex clinical condition characterized by stimulation of a systemic inflammatory response due to an infection. It has a profound deleterious effect on kidney functions leading to sepsis-induced acute kidney injury (AKI). This failure seems to occur through complex mechanisms involving the immune system response, inflammatory pathways, cellular dysfunction and hemodynamic instability. To study the role of cellular energetic metabolism dysfunction and mitochondrial impairment in the occurrence of AKI during sepsis, we developed an inflammation-induced in vitro model using proximal tubular epithelial cells (HK-2) exposed to a bacterial endotoxin (lipopolysaccharide, LPS). This investigation has provided key features on the relationship between endotoxic stress and mitochondrial respiratory chain assembly defects. Firstly, we have shown that renal cells subjected to LPS are no longer capable to use adequately the available oxygen to maintain their metabolic functions. One hypothesis of this down-regulation suggests that impairment in mitochondria oxidative phosphorylation could prevent cells from using oxygen for adenosine triphosphate (ATP) production and potentially could cause sepsis-induced organ failure. Our study has then investigated this possible mitochondrial impairment to explain the decreased O2 consumption rate observed in LPS-treated HK-2 cells. After exposure to LPS, functionality of mitochondria was affected without any disturbance in their spatial organization. LPS seemed rather to interrupt mitochondrial oxidative phosphorylation by blocking cytochrome c oxidase activity. As a consequence, disruptions in the electron transport and the proton pumping across the system occurred, leading to a decrease of the mitochondrial membrane potential, an electron leakage as the form of superoxide anion, a release of cytochrome c in the cytosol and a decrease in ATP production. This irreversible defect in the production of cellular energy would support the concept that kidney failure in sepsis may occur on the basis of cytopathic hypoxia. [less ▲]

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See detailX-ray emission of interacting wind binaries in Cyg OB2
Nazé, Yaël ULg; Cazorla, Constantin ULg; Rauw, Grégor ULg

Poster (2013, September)

Cyg OB2 #5, #8A, and #9 are binary or multiple massive stars in the Cyg OB2 association displaying several peculiarities, such as bright X-ray emission and non-thermal radio emission. Our X-ray monitoring ... [more ▼]

Cyg OB2 #5, #8A, and #9 are binary or multiple massive stars in the Cyg OB2 association displaying several peculiarities, such as bright X-ray emission and non-thermal radio emission. Our X-ray monitoring of these stars reveals the details of their behaviours at high energies, which can be directly linked to wind-wind collisions (WWCs). In addition, the X-ray emission of Cyg OB2 #12, an evolved massive star, shows a long-term decrease, which could hint at the presence of a companion (with associated colliding winds) or indicate the return to quiescence of the system following a recent eruption. [less ▲]

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See detailInteractions of two aphid species on the african eggplant, sorrel and amaranth
Bayendi-Loudit, Sandrine ULg; Chevalier Mendes Lopes, Thomas ULg; Francis, Frédéric ULg

Poster (2013, September)

Aphids (Homoptera: Aphididae) are polyphagous insects which can be found on several crops in temperate zones, as well as in the tropics. The multiplication of Aphis gossypii Glover (C9 cucumber, Burk ... [more ▼]

Aphids (Homoptera: Aphididae) are polyphagous insects which can be found on several crops in temperate zones, as well as in the tropics. The multiplication of Aphis gossypii Glover (C9 cucumber, Burk cotton and Pipo pepper strains) and Myzus persicae Sulzer was studied in the laboratory on three plant species: African eggplant, Solanum aethiopicum, sorrel, Hibiscus sabdariffa, and amaranth, Amaranthus spp. Periodic counts were carried out to monitor population growth. The multiplication rate of M. persicae wass higher than that of A. gossypii when these two species were present together on eggplant. Amaranth was less suitable for the development of both species, but Myzus persicae again had a better multiplication rate than Aphis gossypii. This study illustrated the importance of considering not only one pest species, but the whole herbivore guild, especially when biological control is important. [less ▲]

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See detailEvaluation of a new rapid test for the detection of norovirus antigen in comparison with Real Time RT-PCR
HUYNEN, Pascale ULg; Mauroy, Axel ULg; Gérard, Catherine ULg et al

Poster (2013, September)

Diagnosis of NoV infection mainly relies on molecular methods. A detection of viral antigens can also be performed by immunochromatographic assays, and may be useful in outbreak settings. The aim of this ... [more ▼]

Diagnosis of NoV infection mainly relies on molecular methods. A detection of viral antigens can also be performed by immunochromatographic assays, and may be useful in outbreak settings. The aim of this study was to compare the performances of the new RDT ImmunoCardSTAT!®Norovirus (Meridian Bioscience®, Europe) with a real time RT-PCR. [less ▲]

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See detailImplementing river restoration taking into account constraints of water supply protection: the case study of the Bocq River at Spontin
Peeters, Alexandre ULg; De le Court, Bernard; Verniers, Gisèle

Poster (2013, September)

In the Bocq basin, eastern tributary of the Meuse, restoration works consist of making 20 obstacles passable to improve the free movement of fish and sediment. This presentation focuses on a particular ... [more ▼]

In the Bocq basin, eastern tributary of the Meuse, restoration works consist of making 20 obstacles passable to improve the free movement of fish and sediment. This presentation focuses on a particular case study involving river restoration in a groundwater abstraction zone. In the sixties, a reach of more than 600 meters of the Bocq was completely channelized in order to avoid any risk of contamination of the nearby important drinking water well field area. Ecological quality was consequently impoverished due to the loss of natural habitats (streambed and banks made of concrete and masonry). In addition, the hydraulic conditions (high flow, low depth) make it totally insurmountable for fish. The restoration project started with a 3-year period of consultation with the water abstraction owner to finally reach an agreement on a restoration project taking into account the need of protection of the water abstraction. The project consisted on building rock weirs at regular interval in order to create a succession of 23 steps and pools. Furthermore, various habitats schemes were implemented such as fish shelter, rock berms for aquatic vegetation, and spawning gravel introduction. In addition a small dike and an expansion area for flooding have been completed to protect the water abstraction. This project is being monitored on the basis of geomorphological and ecological analysis. Geomorphological monitoring focuses on the bedload transport with an analysis of flood and the clogging of the gravel layer. Ecological monitoring is based on two indicators (macroinvertebrates and fishes) as well as the analysis of microhabitats. The first results show an improvement after 1 year. [less ▲]

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See detailNegative effect of milk production level on reproduction performances. Not a fatality.
Hanzen, Christian ULg; Glorieux, Géry; Chapaux, Philippe

Poster (2013, September)

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See detailTiO2 templated films used as photoelectrode for solid-state DSSC applications: study of the pore filling by Rutherford Backscattering Spectroscopy
Dewalque, Jennifer ULg; Colson, Pierre ULg; Thalluri, Venkata Visveswara Gopala Kris ULg et al

Poster (2013, September)

Liquid-state dye-sensitized solar cells can suffer from electrolyte evaporation and leakage. Therefore solid-state hole transporting materials are investigated as alternative electrolyte materials ... [more ▼]

Liquid-state dye-sensitized solar cells can suffer from electrolyte evaporation and leakage. Therefore solid-state hole transporting materials are investigated as alternative electrolyte materials. However, in solid-state dye-sensitized solar cells, optimal TiO2 films thickness is limited to a few microns allowing the adsorption of only a low quantity of photoactive dye and thus leading to poor light harvesting and low conversion efficiency. In order to overcome this limitation, high surface area templated films are investigated as alternative to nanocrystalline films prepared by doctor-blade or screen-printing. Moreover, templating is expected to improve the pore accessibility what would promote the solid electrolyte penetration inside the porous network, making possible efficient charge transfers. In this study, films prepared from different structuring agents are discussed in terms of microstructural properties (porosity, crystallinity) as well as effect on the dye loading and Spiro-OMeTAD (2,2',7,7'-tetrakis-(N,N-di-p-methoxyphenylamine)9,9'-spirobifluorene) solid electrolyte filling. Different techniques such as transmission electron microscopy (TEM), atmospheric poroellipsometry (AEP) and UV-visible absorption spectroscopy (UV-vis.) have been used to describe the microstructural features of the films. Besides, we have implemented Rutherford backscattering spectrometry (RBS) as an innovative non-destructive tool to characterize the hole transporting materials infiltration. Templated films show dye loading more than two times higher than nanocrystalline films prepared by doctor-blade or screen-printing and solid electrolyte infiltration up to 88%. [less ▲]

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See detailMagnetic hysteresis cycle and remnant field distribution of bulk high temperature superconductor / ferromagnet hybrids
Philippe, Matthieu ULg; Fagnard, Jean-François ULg; Wera, Laurent ULg et al

Poster (2013, September)

Bulk (RE)BCO materials can be used potentially as powerful permanent magnets. The magnetic flux distribution above a bulk HTS magnet, however, is strongly non-uniform (conic profile predicted by the Bean ... [more ▼]

Bulk (RE)BCO materials can be used potentially as powerful permanent magnets. The magnetic flux distribution above a bulk HTS magnet, however, is strongly non-uniform (conic profile predicted by the Bean model) compared to the rather flat distribution above a ferromagnet. In the present work, we study how FeNi soft ferromagnetic alloys of different shapes can be combined with a bulk, large grain (RE)BCO superconductor (RE denotes a rare-earth element) to improve the distribution of trapped field at the surface or its average value through the volume of the sample. A FeNi ferromagnetic alloy was machined into pieces of various shapes (cylinders and rings) and attached to (i) the top surface of the bulk HTS cylinder to form bulk ferromagnet / superconductor (F/S) hybrids and (ii) to the top and bottom surfaces to form bulk F/S/F hybrids. The magnetic properties of each hybrid structure were measured under axial magnetic field at 77 K. Pick-up coils wound around the superconductor were used to measure the average magnetic induction inside the superconductor while the remnant induction distribution near the top and bottom surfaces was determined by miniature Hall probe mapping. The modifications of the hysteresis curves and flux distributions were analyzed by taking into account the ferromagnet intrinsic properties (intrinsic permeability, saturation) and geometrical properties (shape, size and volume). The results show that the effect of the ferromagnet increases with its volume. In presence of a ferromagnet, the superconductor hysteresis curve shows a combination of a diamagnetic and a ferromagnetic behaviour on which it is worth noting that (i) the bulk remnant magnetization increases and (ii) in the magnetic saturation regime of the ferromagnet, the magnetic effects of the superconductor and the ferromagnet are superimposed. The results also give evidence that flux lines curve through the ferromagnetic component, which produces a decrease of the self-demagnetizing field inside the superconductor. [less ▲]

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See detailInsulin Sensitivity during Hypothermia in Critically Ill Patients
Sah Pri, Azurahisham; Chase, J. Geoffrey; Le Compte, Aaron J. et al

Poster (2013, September)

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See detailHow can long-term experimental plots can help us to understand the sustainability of different phosphorus inputs ?
Renneson, Malorie ULg; Dufey, Joseph; Roisin, Christian et al

Poster (2013, September)

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See detailAssigned value determination on soil materials throughout the whole analytical field introducing bias correction from reference materials
Planchon, Viviane; Renneson, Malorie ULg; Goffaux, Marie-Julie et al

Poster (2013, September)

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See detailThe Ganymede aurora …
Gérard, Jean-Claude ULg; Shematovich, Valery; Bisikalo, Dmitry et al

Poster (2013, September)

In this Report we present the Monte Carlo model for calculation of oxygen UV and IR emissions due to the electron precipitation in the Ganymede polar regions. These techniques will provide column ... [more ▼]

In this Report we present the Monte Carlo model for calculation of oxygen UV and IR emissions due to the electron precipitation in the Ganymede polar regions. These techniques will provide column densities of atmospheric species at better than or equal to 1 km spatial resolution, and will constrain the amount of some specific compounds from limb scans and during stellar occultation. This investigation also needs characterization of the vertical temperature profile from ground up to about 400 km altitude with ~5 km vertical resolution as well as mapping of water vapour concentration. This can be performed by multiple water line observations in the 200-600 μm wavelength range. It shall be complemented by ion and neutral mass spectrometry of plasma particles, radio occultations to measure structures of the neutral atmosphere and ionosphere, and plasma wave measurements to constrain plasma density and temperature of the ionosphere. [less ▲]

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See detailPIXE Analysis for the pigment identification in the Nizet manucript (18th century)
Machowski, Mélanie ULg; Calvo Del Castillo, Helena ULg; Oger, Cécile ULg et al

Poster (2013, September)

Written in 1740, the Nizet Manuscript is a heraldry book compiling the genealogy of the Nizet family (Verviers, Belgium). It presents a large number of hand-painted heraldries in traditional heraldic ... [more ▼]

Written in 1740, the Nizet Manuscript is a heraldry book compiling the genealogy of the Nizet family (Verviers, Belgium). It presents a large number of hand-painted heraldries in traditional heraldic colours; the gold- and silver-like colours have undergone alteration and induced the degradation of the paper. The first inspection of the book with a binocular lens and UV-visible spectroscopy has led to the selection of representative points to be studied by PIXE analysis for the different groups of pigments. The PIXE measurements have been conducted with the cyclotron of the Institute of Nuclear and Atomic Physics and of Spectrometry of the University of Liege. Some pigments have been clearly identified, such as vermillion, umber or brass, while the presence of some others needs to be confirmed, for example azurite or lapis-lazuli. In the case of the green pigments and the organic ones (red, pink and black colours), the PIXE results must be completed by a molecular analysis. In order to exactly identify all the pigments, Raman analyses will be done to complete the pigment identification of the Nizet Manuscript. [less ▲]

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See detailErosion littorale et migrations forcées de réfugiés environnementaux. L'exemple de Cotonou, Bénin
Ozer, Pierre ULg; Hountondji, Yvon-Carmen; De Longueville, Florence ULg

Poster (2013, September)

Situé dans le Golfe de Guinée, le littoral béninois est soumis –sur certains tronçons– à une érosion assez rapide ces dernières décennies. Cette érosion côtière est principalement due actuellement aux ... [more ▼]

Situé dans le Golfe de Guinée, le littoral béninois est soumis –sur certains tronçons– à une érosion assez rapide ces dernières décennies. Cette érosion côtière est principalement due actuellement aux activités humaines parmi lesquelles les perturbations sédimentaires occasionnées par la construction de divers barrages dont celui de Nangbéto sur le fleuve Mono ; le blocage du transit littoral par les ouvrages portuaires de Cotonou ; les carrières de sable exploitées à même la plage ; et la diminution d’apports sédimentaires provenant de l’ouest suite à divers travaux de protection des côtes. En utilisant la fonction multi dates disponible dans Google Earth, cet article estime la superficie érodée à Cotonou entre 2002 et 2011 à l’est de l’exutoire du Lac Nokoué. En outre, il évalue le nombre de maisons détruites ainsi que le nombre de personnes contraintes à une migration forcée. Les figures sont importantes puisque de l’ordre de cent mètres de zone côtière ont totalement disparu au cours des dix dernières années sur un tronçon de près de six kilomètres de long en pleine ville ou en proche périphérie. Cette analyse montre qu’actuellement les dommageables modifications géomorphologiques résultent essentiellement de l’addition non envisagée d’activités humaines couplée à l’absence de gouvernance. Par ailleurs, nous sommes en droit de nous interroger sur les risques d’érosion côtière dans les décennies à venir avec l’amplification annoncée de l’augmentation du niveau des océans due au réchauffement climatique. [less ▲]

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See detailImpact of grazing on carbon dioxide flux exchanges in an intensively managed grassland
Jerome, Elisabeth ULg; Beckers, Yves ULg; Bodson, Bernard ULg et al

Poster (2013, September)

To date, there are few studies assessing the impact of specific management events, particularly grazing, on carbon (C) and carbon dioxide (CO2) fluxes in managed grasslands. Grazing effects are indeed ... [more ▼]

To date, there are few studies assessing the impact of specific management events, particularly grazing, on carbon (C) and carbon dioxide (CO2) fluxes in managed grasslands. Grazing effects are indeed difficult to discern. They vary with the stocking rate and the length of the grazing period. Moreover, they are often masked by environmental responses. The aim of the present study was to assess the impact of grazing on the CO2 fluxes of a grassland grazed by the Belgian Blue breed of cattle. The research was run at the Dorinne Terrestrial Observatory (DTO), located in the Belgian Condroz (50° 18’ 44’’ N; 4° 58’ 07’’ E; 248 m asl.). The site is a permanent grassland of ca. 4.2 ha subjected to intensive management. Grassland carbon budget at the system boundaries is calculated from Net Ecosystem Exchange of CO2 measured by eddy covariance by taking imports and exports of organic C and losses of carbon as methane into account. After 2 years of measurements, the site was close to equilibrium. If management practices (harvest, fertilization and imports as supplementary feedings) and climatic conditions had a significant impact on the C balance, the impact of grazing was uncertain, especially on CO2 fluxes. To do this analysis, we distinguished the long term and the short term impacts of grazing on CO2 fluxes. The long term effect results from the biomass consummation by the cattle and from the cattle effluents that modify assimilation and respiration fluxes. This could be quantified only by comparing fluxes before and after grazing periods. The short term impact is due to cattle respiration that is a part of total ecosystem respiration and should be measured in its presence in the field. For the long term effects of grazing on CO2 fluxes, we analyzed the temporal evolution of gross maximal photosynthetic capacity GPPmax and dark respiration normalized at 10°C (Rd,10). Those parameters were deduced from the response of daytime CO2 fluxes to radiation over 5-day windows. We calculated parameters variations between the beginning and the end of grazing and non-grazing periods (∆GPPmax, ∆Rd,10) and analyzed their dependence to stocking rate. We found a significant decreased of ∆GPPmax that allowed us to quantify the assimilation reduction due to grass consumption by cattle. Discrimination of this impact from flux response to climate was possible only after gathering and treating two years of measurements taken under various climatic conditions. At the opposite, no significant evolution of Rd,10 with the average stocking rate was found. The short term impacts were an increase of CO2 fluxes in presence of cattle. It could be distinguished and quantified only thanks to confinement experiments. Each experiment extended over two days: the first day, cattle was confined in the footprint of the eddy covariance set-up (1.76 ha, 27 LU ha-1) and the second day, it was removed from it. We compared filtered half-hourly data made at 24h intervals, in the presence or absence of cattle, considering that environmental conditions were equivalent (air temperature, wind speed, radiation and wind direction). Livestock contribution to CO2 fluxes was estimated to be 2.25 ± 0.68 kg C LU-1 d-1. [less ▲]

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See detailPersistent right aortic arch associated with an aberrant left subclavian artery arising from a patent ductus arteriosus in a puppy
Rizza, Maïlis ULg; Claeys, Stéphanie ULg; Billen, Frédéric ULg et al

Poster (2013, August 31)

PERSISTENT RIGHT AORTIC ARCH ASSOCIATED WITH AN ABERRANT LEFT SUBCLAVIAN ARTERY ARISING FROM A PATENT DUCTUS ARTERIOSUS IN A PUPPY Rizza M.*, Claeys S.**, Billen F.***, Mc Entee K. ***, Bolen G ... [more ▼]

PERSISTENT RIGHT AORTIC ARCH ASSOCIATED WITH AN ABERRANT LEFT SUBCLAVIAN ARTERY ARISING FROM A PATENT DUCTUS ARTERIOSUS IN A PUPPY Rizza M.*, Claeys S.**, Billen F.***, Mc Entee K. ***, Bolen G.* *Diagnostic Imaging Section, **Small Animal Surgery Section, ***Small Animal Internal Medicine Section, Department of Clinical Sciences (Companion Animal and Equides), Faculty of Veterinary Medicine, University of Liege, Belgium. Introduction Vascular anomalies develop during foetal development and single or multiple aberrant vessels can be present. Persistent right aorta arch (PRAA) represents over 90% of described vascular ring anomalies and can be accompanied by a left ligamentum arteriosum or a patent left ductus arteriosus (approximately 10% of patients) that causes oesophageal entrapment and secondary sub-obstruction. Radiography is an effective means of detecting vascular ring anomalies when oesophageal dilation and left-sided tracheal displacement are visible. Computed tomography angiography (CTA) is necessary to confirm the nature and the patency of the vascular anomalies present and to identify which of the identified anomalies is causing the clinical signs. Materials and methods A 3.5-month-old, male French Bulldog was presented for regurgitation and vomiting since weaning. Besides a low body score, physical exam was unremarkable. Hypoglycemia was observed on routine blood analysis. Thoracic radiographs and CTA of the thorax were performed. Results The radiographs revealed severe oesophageal dilation cranial to the base of the heart and a ventral and left-sided tracheal displacement. A congenital oesophageal diverticulum secondary to a vascular anomaly was suspected. CTA showed multiple vascular anomalies. A PRAA was observed. An aberrant right subclavian artery (ARSA) was identified originating from the PRAA next to the brachiocephalic trunk. A patent left-to-right patent ductus arteriosus (PDA) was detected between the aorta and the pulmonary trunk and an aberrant left subclavian artery (ALSA) originated from the PDA. The oesophagus was compressed between the PDA and the trachea and was dilated cranially to this narrowing. Endoscopy revealed severely esophageal distension cranially to an extraluminal stenosis. Surgery was performed to ligate and cut the PDA. Discussion Seven types of vascular ring anomaly are described: types I - III have a PRAA, type IV has a double aortic arch, and types V -VII have a left aortic arch with combinations of persistent right ligamentum arteriosum and right subclavian arteries. In the patient described here, the vascular ring anomalies are a novel variant of the defined types. To the authors’ knowledge, an ALSA originating from a PDA has not been described previously. The severe compression of the oesophagus with severe dilation cranial to the heart was caused by the PDA and was resolved by surgical intervention. In conclusion, CTA is necessary to determine which vascular anomalies are present and to identify which of these anomalies is responsible for the clinical signs. This technique enables accurate pre-operative planning. Pownder S. Scrivani PV. Non-selective computed tomography angiography of a vascular ring anomaly in a dog. J Vet Cardiol. 2008 Dec;10(2):125-8 Henjes CR, Nolte I, Wefstaedt P. Multidetector-row computed tomography of thoracic aortic anomalies in dogs and cats: patent ductus arteriosus and vascular rings. BMC Vet Res. 2011 Sep 23;7:57 [less ▲]

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See detailNi/Al2O3 xerogel catalysts for biogas cleaning
Claude, Vincent ULg; Heinrichs, Benoît ULg; Lambert, Stéphanie ULg

Poster (2013, August 29)

This poster summarize the firsts results of the PhD project started on October 2012 about the catalytic purification of biogas. The aim of this project consists in the development of Ni/Al2O3 catalyst in ... [more ▼]

This poster summarize the firsts results of the PhD project started on October 2012 about the catalytic purification of biogas. The aim of this project consists in the development of Ni/Al2O3 catalyst in order to reform the tars present in the outlet gas of biomass gasifier. In order to obtain catalysts with high performance and lifetime, materials need to have optimized specific surface and metal particle dispersion. This poster investigate the effect of different surfactants (Pluronic P123; F127; stéarique acide, EDAS) on the materials properties. [less ▲]

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See detailA Gene Regulatory Network Model to Assess the Stability of the Cartilage Phenotype
Kerkhofs, Johan ULg

Poster (2013, August 29)

Introduction Chondrocyte hypertrophy entails the switching of a genetic program driven by Sox9 to one under control of the osteoblast master regulator Runx2. The switch is a prerequisite step in the bone ... [more ▼]

Introduction Chondrocyte hypertrophy entails the switching of a genetic program driven by Sox9 to one under control of the osteoblast master regulator Runx2. The switch is a prerequisite step in the bone forming process (endochondral ossification) during development and in postnatal fracture repair of larger bone defects. However, this switch can also be detrimental in tissue engineered cartilage constructs and in osteoarthritis development [Saito, 2010]. Therefore, a detailed model of the pathways that can facilitate, or inhibit, this phenotypic switch will lead to a more profound understanding of these processes and provide hints as to how to manipulate them. Methods The model formalism accommodates the qualitative information that is typically available in developmental studies. The literature based network comprises 46 nodes and 161 interactions, shown to be important in endochondral ossification. To simulate network dynamics in discrete time the normalized value of each gene is determined by additive functions where all interactions are assumed to be equally powerful. Furthermore, each species is represented by a fast variable (activity level, as determined by post translation modifications) which is assumed to be in equilibrium with a slow variable (mRNA) at all times. Through a Monte Carlo approach the importance of each node in the stability of chondrocytic phenotypes (proliferating, hypertrophic) is assessed in random initial conditions. A perturbation analysis of the stable states is used to determine the transition likelihood between them as a second measure of stability. Results Both measures of stability indicate that the hypertrophic (Runx2 driven) state is more stable than the proliferating one driven by Sox9. The results for the second measure are given in Fig.1. This higher stability seems to be partly conferred by faster reactions that favour the hypertrophic phenotype. In addition, the results point out that some transcription factors are necessary for the induction of a certain phenotype, whereas other transcription factors are required to maintain the phenotype, but are not necessary capable of inducing it. Discussion These results may relate to the difficulty experienced by researchers in maintaining a stable cartilage phenotype in culture and the occurrence of ectopic hypertrophy in osteoarthritis. By analysing the effect of changes to individual nodes, strategies to stabilise the proliferating phenotype can be developed. Overall, the model allows the importance of several important factors in the fate decision of mesenchymal cells to be quantitatively assessed based mainly on topological information. [less ▲]

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See detailTime-history of the gravel sheet in Ardennian rivers over the last 100,000 years
Houbrechts, Geoffrey ULg; Denis, Anne-Cécile ULg; Juvigné, Etienne ULg et al

Poster (2013, August 27)

It is generally held that, in north-western Europe, the main part of the gravel sheets under river beds were deposited during the Weichselian period in a periglacial environment. However, other parameters ... [more ▼]

It is generally held that, in north-western Europe, the main part of the gravel sheets under river beds were deposited during the Weichselian period in a periglacial environment. However, other parameters such as propagation of knickpoints in fluvial networks may also influence incision or aggradation. However, only few studies have dated the periods of formation of the gravel sheets and have described their properties. The first aim of this research was to determine the thickness of the gravel sheets still remaining under the river beds and to estimate the potential incision of these rivers before reaching the bedrock. Then we tried to answer a number of other questions: When did these thick gravel deposits fill the valley bottom? When were the lowest terraces abandoned? When did the rivers incise the bedrock? What is the morphology of the bedrock under the gravel layer? Numerous boreholes were made by percussion drilling in different floodplains of the Ardenne Massif and core samples were taken, down to the bedrock. Afterwards, different volcanic tephra from the Late Pleistocene were used as stratigraphic markers to date the relative periods of terrace formation and to reconstruct the past evolution of the gravel sheets. Pollen and metallurgic slag were also used to date the periods of bed level evolution. In the Ardennian massif, the thickness of the gravel sheet beneath the river beds is very variable (from 10 m in the downstream part of the Ourthe River to less than 1 m in the upper catchments). In some valleys, weathered bedrock has been observed under the gravel sheet to a thickness of several meters. Different phases of accumulation and incision over the last 100,000 years have been dated. Some evolutions can be clearly linked to climate changes but some modifications of bed levels also occurred during the Weichselian period and could be a response to the propagation of knickpoints in the fluvial networks. [less ▲]

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See detailEstimation of dominance variance with sire-dam subclass effects in a crossbred population of pigs
Dufrasne, Marie ULg; Faux, Pierre ULg; Piedboeuf, Maureen et al

Poster (2013, August 26)

Nonadditive genetic effects may be not negligible but are often ignored in genetic evaluations. The most important nonadditive effect is probably dominance. Prediction of dominance effects should allow a ... [more ▼]

Nonadditive genetic effects may be not negligible but are often ignored in genetic evaluations. The most important nonadditive effect is probably dominance. Prediction of dominance effects should allow a more precise estimation of the total genetic merit, particularly in populations that use specialized sire and dam lines, and with large number of full-sibs, like pigs. Computation of the inverted dominance relationship matrix, D-1, is difficult with large datasets. But, D-1 can be replaced by the inverted sire-dam subclass relationship matrix F-1, which represents the average dominance effect of full-sibs. The aim of this study was to estimate dominance variance for longitudinal measurements of body weight (BW) in a crossbred population of pigs, assuming unrelated sire-dam subclass effects. The edited dataset consisted of 20,120 BW measurements recorded between 50 and 210 d of age on 2,341 crossbred pigs from 89 Piétrain sires and 169 Landrace dams. A random regression model was used to estimate variance components. Fixed effects were sex and date of recording. Random effects were additive genetic, permanent environment, sire-dam subclass and residual. Random effects, except residual, were modeled with linear splines. Only full-sib contributions were considered by using uncorrelated sire-dam classes. Estimated heritability of BW increased with age from 0.40 to 0.60. Inversely, estimated dominance decreased with age, from 0.28 to 0.01. Ratio of dominance relative to additive variance was high at early age (58.3% at 50 d) and decreased with age (2.6% at 200 d). Those results showed that dominance effects might be important for early growth traits in pigs. However, this need to be confirmed and dominance relationships will be included in the next steps. [less ▲]

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See detailHerd-test-day variability of methane emissions predicted from milk MIR spectra in Holstein cows
Vanrobays, Marie-Laure ULg; Kandel, Purna Bhadra ULg; Soyeurt, Hélène ULg et al

Poster (2013, August 26)

The aim of this study was to estimate the herd-test-day (HTD) effect on milk yield, fat and protein content, and methane (CH4) emissions of Walloon Holstein first-parity cows. A total of 412,520 test-day ... [more ▼]

The aim of this study was to estimate the herd-test-day (HTD) effect on milk yield, fat and protein content, and methane (CH4) emissions of Walloon Holstein first-parity cows. A total of 412,520 test-day records and milk mid-infrared (MIR) spectra of 69,223 cows in 1,104 herds were included in the data set. The prediction equation developed by Vanlierde et al. (Abstract submitted to EAAP 2013; R² of cross-validation=0.70) was applied on the recorded spectral data to predict CH4 emissions (g/d). Daily CH4 emissions expressed in g/kg of milk were computed by dividing CH4 emissions (g/d) by daily milk yield of cows. Several bivariate (a CH4 trait with a production trait) random regression test-day models including HTD and classes of days in milk and age at calving as fixed effects and permanent environment and genetic as random effects were used. HTD solutions of studied traits obtained from these models were studied and presented large deviations (CV=17.54%, 8.93%, 4.68%, 15.51%, and 23.18% for milk yield, fat and protein content, MIR CH4 (g/d), and MIR CH4 (g/kg of milk), respectively) indicating differences among herds, especially for milk yield and CH4 traits. HTD means per month of milk yield and fat and protein contents presented similar patterns within year. The maximum of monthly HTD means corresponded to the spring (pastern release) for milk yield and to the winter for fat and protein contents. The minimum corresponded to the month of November for milk yield and to the summer for the other traits. For MIR CH4 (g/d), monthly HTD means showed similar patterns as fat and protein content within year. MIR CH4 (g/kg of milk) presented maximum values of monthly HTD means in November and minimum values in May. Finally, results of this study showed that HTD effects on milk production traits and on MIR CH4 emissions varied through herds and seasons. [less ▲]

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See detailOpal-CT precipitation in a clayey soil explained by geochemical transport model of dissolved Si (Blégny, Belgium)
Ronchi, Benedicta; Barao, A.L.; Vandevenne, F. et al

Poster (2013, August 25)

Opal-CT precipitation controlling dissolved Si export Dissolved Si (DSi) exported by rivers are controlled by geological, hydrological and biological cycle processes [1]. The DSi concentrations measured ... [more ▼]

Opal-CT precipitation controlling dissolved Si export Dissolved Si (DSi) exported by rivers are controlled by geological, hydrological and biological cycle processes [1]. The DSi concentrations measured in a river of an upstream catchment in eastern Belgium (Blégny, Land of Herve) don’t vary seasonally (6.91±0.94mgL-1; n=363). Si concentrations in pore water are often higher and vary more (8.65±3.65mgL-1; n=128). The decrease of DSi along the flowpath of water is due to sink processes, i.e. precipitation, adsorption or uptake by vegetation. As the DSi in the river does not show any seasonal variation, uptake by vegetation can be ruled out [1] whereas precipitation or adsorption can control the DSi drained by the stream water. This hypothesis is confirmed by XRD and DeMaster analysis. At 0.1m depth the soil is constituted of 62% quartz, 7% K-feldspar, 6% plagioclase, 3.2% carbonates, 18.9% Al-clay, 1.47% Kaolinite, 0.63% Chlorite and 0.2% amorphous Si, probably of biogenic origin. At 1.5m depth, the amounts of several minerals (35.8% quartz, 0.6% K-feldspars, 0.9% plagioclase, Al-clay 14.7%) drop drastically. Carbonates, chlorite and kaolinite are absent whereas 40.4% opal-CT appears. The precipitation of opal-CT controls the DSi export of this catchment. Development of geochemical transport model To descripe DSi export from a catchment a geochemical transport model is developped in HP1 which couples the water flux model Hydrus with the geochemical model PHREEQC [2]. Our model is based on the conceptual model developped in [3]. First results show different DSi export dynamics in the unsaturated zone than in the aquifer due to different pCO2 values and varying soil moisture conditions. Further development of the model will help to find out the reason of opal-CT precipitation in this setting. [1]Fulweiler, Nixon (2005) Biogeochemistry 74:115–130. [2] Simunek, Jacques, van Genuchten, Mallants (2006) JAWRA 42:1537-1547. [3] Ronchi et al. (2013). Silicon, 5(1), 115–133. [less ▲]

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See detailDifferences in locomotor activity in two syntopic spadefoot toad species (genus Pelobates)
Székely, Diana; Denoël, Mathieu ULg; Székely, Paul et al

Poster (2013, August 25)

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See detailInfluence of breed and previous storage time on color and lipid stability of beef packaged in high-oxygen atmosphere
Didimo Imazaki, Pedro Henrique ULg; Tahiri, Assia ULg; Thimister, Jacqueline ULg et al

Poster (2013, August 20)

The aim of this study was to compare the effect of two breeds (Belgian Blue vs. Limousin) and previous vacuum storage time on color and lipid stability of meat packaged in high-oxygen atmosphere. Vacuum ... [more ▼]

The aim of this study was to compare the effect of two breeds (Belgian Blue vs. Limousin) and previous vacuum storage time on color and lipid stability of meat packaged in high-oxygen atmosphere. Vacuum packaged striploins from Belgian Blue and Limousin cows were stored at −1 °C and +4 °C for up to 60 days and analyzed. Part of these samples were repackaged under modified atmosphere – 70 % O2/30 % CO2 – at different times, stored 2 days at +4 °C and 5 d at +8 °C, and then analyzed. The following parameters were evaluated: color (CIE L*a*b*), metmyoglobin %, lipid oxidation (TBARS) and fat content. Color measurement and metmyoglobin % determination showed greater pigment stability in Belgian Blue samples than in Limousin. Belgian Blue also presented higher lipid stability (TBARS). A positive correlation between pigment oxidation and lipid oxidation was highlighted. The greater amount of fat in meat of Limousin could partially explain its higher sensitivity to oxidation. Nevertheless, other factors may be involved in oxidative stability such as metmyoglobin reducing activity and antioxidant capacity. An understanding of the oxidative processes and their interaction would provide a basis for explaining quality deterioration in meat and for developing strategies to maintain sensory qualities. [less ▲]

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See detailDevice-based controlled local delivery for the treatment of peritoneal pathologies
Riva, Raphaël ULg; Krier, Fabrice; Defrère, Sylvie et al

Poster (2013, August 18)

This contribution aims at reporting the developpment of a controlled drug delivery system (DDS) dedicated to the treatment of intra-peritoneal pathologies, especially endometriosis. At present time ... [more ▼]

This contribution aims at reporting the developpment of a controlled drug delivery system (DDS) dedicated to the treatment of intra-peritoneal pathologies, especially endometriosis. At present time, endometriosis is generally treated by daily oral absorption of drug with the purpose to improve the life quality of patients by the reduction of the pain caused by endometrial lesions. Nevertheless, deleterious side-effects, mainly infertility, are observed as a consequence of the important amount of absorbed active principle. One main advantage of controlled drug delivery devices, e.g. polymer implants, is to maintain sustained drug release over a prolonged period of time thereby eliminating fluctuations in the drug plasma concentration. Moreover, DDS allows a local release of the drug at a specific area, which significantly decreases the active principle concentration in the body and limits side-effects. The peritoneal cavity is a convenient site for the implantation of a DDS against endometriosis because large parts of lesion are localized in this region. At our knowledge, no application of an implant dedicated to the treatment of endometriosis is reported in the literature, whereas the local controlled release of an active principle presents several advantages compared to systemic administration. In this study, anastrozole (2,2’-[5-1H-1,2,4-triazole-1-yl-methyl)-1,3-phenylene]bis(2-methylpropiononitrile)), a well-known aromatase-inhibiting drug, was selected as active molecule. Typically, two non-biodegradable polymers were tested for the elaboration of an anastrozole loaded intra-peritoneal implant, namely polydimethylsiloxane (PDMS) and poly(ethylene-co-vinyl acetate) (EVA). As preliminary research, the ‘in vivo’ biocompatibility of PDMS and EVA in the intra-peritoneal cavity was confirmed by implantation of PDMS and EVA rod-shaped implants in rats. The kinetic of release was determined ‘in vitro’ and confirmed ‘in vivo’. Besides, the efficiency of the implants was improved by the addition of a polymer membrane, which allowed a controlled release of anastrozole over a period of 400 days. [less ▲]

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See detailStudy of photosynthesis of Chlamydomonas reinhardtii under High and Low CO2 conditions.
de Marchin, Thomas ULg; Ghysels, Bart ULg; Franck, Fabrice ULg

Poster (2013, August 12)

In photoautotophically air-grown microalgae, CO2 availability is usually limited. The unicellular green algae Chlamydomonas reinhardtii can adapt to low CO2 concentration with the inorganic carbon ... [more ▼]

In photoautotophically air-grown microalgae, CO2 availability is usually limited. The unicellular green algae Chlamydomonas reinhardtii can adapt to low CO2 concentration with the inorganic carbon concentration mechanism (CCM). This has been extensively studied in the past but functional adaptation of the photosynthetic apparatus has been less studied. Photosynthetic organisms can cope with CO2 limitation by dissipating excess absorbed energy with the help of different energy dissipating mechanisms like energy-dependent non-photochemical quenching (NPQ). In Chlamydomonas reinhardtii, this process only seems to develop to high levels in extreme conditions combining high light and strong CO2 limitation. Under moderate CO2 limitation, absence of important energy-dependent NPQ suggests the development of another energy dissipating mechanism. We compared the growth and functional adaptations of the photosynthetic apparatus of the wild-type strain 1690 grown in photobioreactor under low and high CO2 bubbling, 0.039% and 10%, respectively. Under low CO2, where growth was 2 to 4 times slower than under high CO2, the non-linear relationship between electron transport rate (derived from PAM fluorescence measurements) and gross oxygen evolution rate suggested that a significant portion of the electron flux is directed to oxygen at light intensities approaching photosynthetic saturation (either at PSI or at PTOX). The use of the mutant strain PTOX2 indicated that O2 reduction occurs mainly at PSI and not at PTOX. Low temperature fluorescence emission spectra indicated no significant difference in excitation energy distribution between PSI and PSII. Western blot analysis showed no major differences in abundance of Rubisco or of photosystem subunits between the two conditions. In contrast, cytochrome f abundance was lower in high CO2 condition. Although energy-dependent NPQ remained weak, low CO2 cells were characterized by a higher xanthophyll deepoxydation index which usually indicates more dissipation as heat, as also suggested by increased Lhcsr3 expression. Despite a higher ATP requirement of the CCM mechanism in low CO2 condition, only minor difference in cyclic electron transport could be found if compared to high CO2 condition (as determined by P700 spectroscopic measurements). In Chlamydomonas, conflicting views were expressed in earlier studies on the amplitude and role of Mehler-type O2-uptake at steady state. Our analysis of oxygen evolution, electron transport and NPQ after growth under different combinations of light intensities and CO2 supply rates allows us to define Mehler-type alternative electron transport as an important and flexible response to photosynthetic electron transport saturation in Chlamydomonas. [less ▲]

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See detailInteractions with musical long-term memory are a critical component of musical working memory
Gorin, Simon ULg; Majerus, Steve ULg

Poster (2013, August 10)

The nature and mechanisms of working memory (WM) for musical information remain poorly understood. The aim of this study is to show that musical WM strongly depends upon long-term memory (LTM) mechanisms ... [more ▼]

The nature and mechanisms of working memory (WM) for musical information remain poorly understood. The aim of this study is to show that musical WM strongly depends upon long-term memory (LTM) mechanisms and requires access to the long-term musical knowledge base. Two groups of participants (musicians and non-musicians) participated first in an implicit learning task during which they heard for about 30 minutes a continuous sequence of tones governed by a new musical grammar. Then, they performed an immediate serial recall task of musical sequences of increasing length; half of the sequences were constructed in accordance to the rules of the new grammar presented during the implicit learning task. Participants have to reproduce the sequences by humming and their performances were calculated on the basis of the deviation between their production and the stimulus needed to be reproduced. The results showed a significant advantage for the lists governed by the grammar previously learned. Overall, this study shows that performance on a musical WM task is enhanced by musical knowledge stored in LTM. This study is the first to demonstrate the dependency of musical WM on musical LTM knowledge, implying that existing models of musical WM need to be extended to account for this WM-LTM interaction. [less ▲]

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See detailProfitability of using warning system for foliar disease of wheat in the Grand-Duchy of Luxembourg.
El Jarroudi, Moussa ULg; Kouadio, Louis; Beyer, Marco et al

Poster (2013, August 10)

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See detailFacile Encapsulation of Sn nanocrystals in GeS2 Matrix for High-Performance Lithium-ion Battery Anodes
Singh, Ajay; Krins, Natacha ULg; Milliron, Delia J.

Poster (2013, August 05)

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See detailWarming promotes cheatgrass invasion in mixed-grass prairie
Blumenthal, Dana; Kray, Julie; Morgan, Jack et al

Poster (2013, August 04)

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See detailEstimation of genetic parameters of racing traits of Arabian horses in Algeria
Tennah, Safia ULg; Kafidi, Nacereddine; Antoine-Moussiaux, Nicolas ULg et al

Poster (2013, August)

The results of the flat races organized in Algeria from 1995 to 2007 by the Algerian Horse Racing Society, were used to estimate genetic parameters of racing performances of Arabian horses. The data ... [more ▼]

The results of the flat races organized in Algeria from 1995 to 2007 by the Algerian Horse Racing Society, were used to estimate genetic parameters of racing performances of Arabian horses. The data consist of 36 492 race records, obtained from 913 horses. The pedigree file of the horses includes 1812 animals from 166 stallions and 392 mares. The analysis was performed on two traits: the logarithm of average annual virtual earnings per start (LAEV/S) and a normalized ranking (PERF). To identify the fixed effects to be included in the genetic model, a preliminary analysis was conducted using the General Linear Models (GLM) procedure from SAS software. The effects of age (3 to 8 years and older), sex (male or female), year (1995 to 2007) and the interaction between year of the race and age and between sex and age were included in the model for both traits. In addition, two random effects, a direct genetic effect of the animal and a permanent environmental effect were included in the mixed model. The variance components and genetic parameters were estimated by the restricted maximum likelihood (REML), procedure using the MTDFREML program. The analysis, using a repeatable animal model, led to the following estimation of genetic parameters: for LAEV/S, heritability was 0.23 (±0.04), while estimate of repeatability was 0.34 (±0.04). The heritability for the normalized ranking was higher, 0.37 (±0.05), indicating that this trait might be more appropriate for breeding programs of Arabian horses in Algeria. The repeatability estimate for the normalized ranking was 0.59 (±0.04) and the genetic correlation between this trait and LAEV/S was 0.79. [less ▲]

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See detailModelization of photosynthetic and respiratory maximal activities as a function of culture parameters in Chlamydomonas reinhardtii using design of experiment and data analysis by JMP (SAS Institute)
Gerin, Stéphanie ULg; Mathy, Grégory; Franck, Fabrice ULg

Poster (2013, August)

We aimed to modelize the dependence of photosynthetic as well as cytochromial and alternative respiratory maximal activities upon different culture parameters, i.e. light intensity and acetate, carbon ... [more ▼]

We aimed to modelize the dependence of photosynthetic as well as cytochromial and alternative respiratory maximal activities upon different culture parameters, i.e. light intensity and acetate, carbon dioxide, nitrate and ammonium concentrations, in the model unicellular green alga Chlamydomonas reinhardtii. Culture parameters were submitted to a dedicated statistical software (JMP 10.0, SAS Institute) for the generation of a design of experiment. Measurements of oxygen concentrations were carried out to quantify maximal activities. JMP was further used to detect culture parameters exerting a statistically significant effect on maximal activities and to modelize the dependence of maximal activities upon these culture parameters of interest. [less ▲]

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See detailPhosphorus availability in agricultural soils of Wallonia (Belgium) - A modeling approach
Cobert, Florian ULg; Pourret, Olivier; Renneson, Malorie ULg et al

Poster (2013, August)

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See detailAn exclosure experiment to assess the impact of ungulates on plant diversity in Belgium
VANDENSCHRICK, François; Lehaire, François ULg; Licoppe, Alain ULg et al

Poster (2013, August)

The erosion of biodiversity is caused by many factors. Large ungulates, which occupy a large part of the Walloon forests, can also influence the distribution and dynamics of plant species. Therefore, they ... [more ▼]

The erosion of biodiversity is caused by many factors. Large ungulates, which occupy a large part of the Walloon forests, can also influence the distribution and dynamics of plant species. Therefore, they impact the biodiversity of our temperate forests. The aim of the present study is to identify changes in forest understory vegetation due to the pressure exerted by wild ungulates thanks to an exclosure-enclosure experiment. This study was conducted on a high plateau of the Ardenne, in the forest of St Michel Freyr (South Belgium). The forested area is dominated by beech and spruce where red deer, wild boar and roe deer are living in sympatry. 150 sampling plots were established in 2000. Each plot consisted of two closed enclosures of 4 m² each and one exclosure of 4 m² as control under pressure of ungulates. Sampling was carried out systematically by a 500m-square mesh. The cover rate and height of some easily identifiable species were measured regularly since 2000 (2001, 2002, 2003, 2004, 2007, 2011-2012). In addition, we identified each herbaceous species in 2011-2012 to analyze the species richness after more than 10 years exclosure. Ligneous species showed an increase of developpement in the fenced area. These species are more impacted when they are not much represented in the study site.Species richness and diversity are higher in areas impacted by herbivory. Monocotyledons are mainly favorised while tree seedlings are unfavorised. Browsing on the trees keeps the area free from high vegetation and allows light to reach the ground. In the same time, herbaceous species have a lower cover rate in the enclosure because of the competitive exclusion induced by shrub and tree seedlings layer. If the apparition of most species is favorised by ungulates, they induce a lag of gowth on dicotyledons which have a higher palatability than monocotyledons. Ungulates have the ability to impact the distribution of vegetal species by the modification of the competitive interaction. By their pressure on tree and shrub species, they induce a higher diversity of the ground flora. However, this change in vegetation composition is slow and requires a long-term studie, specially in areas of low biomass productivity like the St-Hubert forest. [less ▲]

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See detailFine-scale analysis of ungulate-vehicle collisions in Southern Belgium
maron, Julie; Lehaire, François ULg; Morelle, Kevin ULg et al

Poster (2013, August)

Ungulate-vehicle collisions (UVC) are an increasing phenomenon in many European countries. These road accidents are a threat to wildlife populations but also to human safety and generate high economic ... [more ▼]

Ungulate-vehicle collisions (UVC) are an increasing phenomenon in many European countries. These road accidents are a threat to wildlife populations but also to human safety and generate high economic costs. Wallonia, the Southern part of Belgium, is also affected by the UVC problem and offers an interesting study area because of its very dense road network and increasing big game populations. The aim of our study was to determine where and when UVC hotspots occurred along highways in Wallonia, in order to provide recommendations regarding the location and design of mitigation measures. The study site is located in Wallonia (Southern Belgium) in the provinces of Liege and Namur (5,875 km²). Ungulates species present in this area are wild boar, roe deer and red deer. The UVC data were collected by the police and covered the period between 2008 and 2011 (n= 2,704). We analyzed the landscape and road-related variables of sections with high UVC risk in contrast with section of low risk. The landscape and road-related variables related to the location of UVC were highlighted using a generalized linear model (GLM) with simulated pseudo-absences. Concerning traffic accidents, the most involved game species are wild boar (37% of all casualties). That’s why the amount of data on wild boar was higher than for the other species. The results of the spatial and temporal analysis of wild boar-vehicle collisions (WVC) are therefore more accurate than for the other species. Consequently we decided to focused on the wild boar in the present poster. Temporal analysis showed strong variations in the WVC frequency over time, on the daily and seasonal scale. These critical periods correspond to the activity periods of the species (more UVC at night and during autumn and winter). The study also points out a negative correlation between the occurrence of UVC and the traffic volume (R² = 9.79%). This result doesn’t match with the literature but can be explained if we assume that when traffic increase, the road represents a more impassable barrier for animal species. As expected we also noticed a positive correlation between game density and UVC risk. These results indicate clear spatial and temporal clustering of WVC. Identification of hotspots enables us to identify the priority areas where mitigation measures must be considered. For further research, the accuracy of the police data should be improved in order to predict more exactly the risk of UVC. This would also make the mitigation measures more cost-effective. [less ▲]

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See detailUse of visible-near infrared spectroscopy to determine cheese properties
Troch, Thibault ULg; Vanden Bossche, Sandrine; De Bisschop, Céline et al

Poster (2013, August)

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See detailAssessment and monitoring of forest-game balance: an exclosure experiment
Lehaire, François ULg; Licoppe, Alain ULg; Lejeune, Philippe ULg

Poster (2013, August)

During the last decades, populations of large ungulates have largely increased, strengthening the pressure exerted by these species on forest vegetation. Therefore, monitoring this pressure has become ... [more ▼]

During the last decades, populations of large ungulates have largely increased, strengthening the pressure exerted by these species on forest vegetation. Therefore, monitoring this pressure has become unavoidable for sustainable forest management. Such monitoring requires a rigorous approach in order to evaluate objectively the balance between game population and forestry. The use of exclosure experiment offers an interesting solution to observe the effects of game populations on forest ecosystem. When objectives expected from forest management are clearly defined, exclosure experiments can effectively be used as a monitoring tool, to allow detecting unbalanced situations, for example, herbivore pressure threatening forest regeneration. The monitoring tool combines on one side an exclosure, defined as "the real environment", fully accessible to herbivores and, on the other side an enclosure, which is the "control treatment", fenced and therefore unavailable to any large ungulates. Our main aim was to compute a set of indicators characterizing the ecological changes due to large herbivores pressure on forest ecosystems. We identified 2 categories of ecological indicators: the short-term and the medium-term indicators. Short-term indicators require only two-year of monitoring to correctly quantify herbivore pressure whereas medium-term indicators require at least 4 years of monitoring. The study site is located in Southern Belgium (Wallonia), in mixed beech and oak forests. The predominant vegetation type is the "Luzulo-Fagetum", typically found in acidophileous beech forests. The ungulate species of interest are red deer, roe deer, wild boar and mouflon. In 2006, enclosures and exclosures (4 x 4 m) were installed in 17 sites scattered in two zones with contrasted deer densities to assess indicators efficiency. Between 2006 and 2012, we performed floristic surveys and we recorded the height, density and cover of the understory vegetation of every plot. [less ▲]

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See detailGetting insights on bovine mastitis treatment efficacy based on tissular indicators with an integrated udder health management file: Project LAECEA.
Theron, Léonard ULg; Reding, Edouard; Rao, Anne-Sophie ULg et al

Poster (2013, August)

Mastitis is the most “antibiotic consuming” pathology in dairy medicine. Though antibiotics and antibiograms are known to vets since the early fifties, our practices did not evolved a lot from empiric ... [more ▼]

Mastitis is the most “antibiotic consuming” pathology in dairy medicine. Though antibiotics and antibiograms are known to vets since the early fifties, our practices did not evolved a lot from empiric antibiotic therapy. Indeed, the need for a treatment, the cost and the delay for an antibiogram are most of the time incoherent with a routine practice. Nevertheless, there is a surge for rational use of antibiotics. Our study was based on 1100 mastitis events from 30 Belgian farms collected between January 2011 and June 2012. We chose to compare tissular cure (TC) based on the threshold of 200.000 somatic cells/ml in milk at milk control at least 60 days after the clinical mastitis event. Regarding the mastitis event, severity (according 3 grades: alteration of milk as grade 1, alteration of quarter as grade 2 and alteration of general state as grade 3), quarter, treatments were recorded. We also assessed a chronicity status based on previous somatic cell count (SCC) of the cow. It was considered a new case a cow which at least 15 days before had an SCC <200.000 cells/ml, other were marked as chronic cases. In our distribution, we see a seasonal rise of incidence between January and May. This period would represent twice as many mastitis as the summer period. Overall TC reaches 46% of all mastitis events, which is quite poor. Rear quarters had significantly lower TC (p<0,05%). Grade 3 mastitis had lower TC, 42,6% (p<0.05%) versus 48,9 % for grade 2 and 44,2% for grade 1. Almost 49% of all mastitis was considered as chronic cases, which TC was 33% on average, whereas new cases reached 55,3% TC. Study of treatment was frustrating given the high number of different combinations of treatments. It was underlined that 4th generation cephalosporins (C4G) were the most used in our cohort, followed by aminopenicillin/methicillin association (PENA/PENM) and 1st generation cephalosporins/aminoglycosids (C1G/AG) association. Of these intramammary treatments, 20% of the cases were submitted to a second intramammary drug, mostly C1G or C1G/AG. One third of the cases were treated parenterally with antimicrobials, mostly macrolids, fluoroquinolones and penethacillin. Finally, 10% of mastitis was treated with anti-inflammatory drugs, mostly tolfenamic acid and flunixin-meglumin. Comparing mastitis without use of a secondary intramammary drug, only PENA and C1G/AG reached more than 60% TC. Considering new cases, then C1G/AG, PENA/PENM and Prednisolone containing specialties were above 60% TC. Use of a parenteral injections increased TC only on new cases (+12%), but not on chronic cases. Refining by severity, TC improved with a parenteral on new cases, mainly in grade 1 (+20%). Regarding associated factors, TC was negatively affected by chronicity, parity and lactation stage. Indeed, TC was lower on cases from more than 4 month in milk, third lactation (OR = 2.8 for no cure) compared with previous, and chronic cases (OR=2,6). Seemingly, chronicity was positively associated with parity and season. The 3rd parity cases had higher chances to be chronic ones (OR = 1,7), as well as cases from April to September (OR = 1,6). This evaluation of cure is rather simple and has a good variability which allows several questions about the real match between antimicrobial treatment for mastitis and the udder inflammation. Based on our epidemiological data, we can modify routine management of mastitis, as some cases might not worth the antimicrobial treatment. [less ▲]

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See detailBioindicators for measurement of red deer pressure on understory vegetation in temperate deciduous forests
Lehaire, François ULg; Morelle, Kevin ULg; Ligot, Gauthier ULg et al

Poster (2013, August)

During the last decades, populations of large herbivores have largely increased. Consequently, their pressure on forest vegetation has been exacerbated, reaching in some cases levels that reduced the ... [more ▼]

During the last decades, populations of large herbivores have largely increased. Consequently, their pressure on forest vegetation has been exacerbated, reaching in some cases levels that reduced the diversity of forest ecosystem services. Assessing the balance between timber production and hunting activities remains a crucial question for forest managers who hence need reliable tools such as ecological indicators. Our aim was to review ecological indicators that characterize the pressure of red deer (Cervus elaphus L.) on understory vegetation in temperate deciduous forest ecosystem. The choice of plants on which the variables are measured is crucial to accurately characterize the deer pressure. This choice must take into account the feeding behavior of red deer, silvicultural objectives, ease of the measurement and the occurrence of these plants within the studied habitat. Generally, it is more appropriate to use common species with a wide ecological amplitude. The choice of indicator plants must take into account plant abundance and palatability, as they both affects considerably the performance of the ecological indicator. The variability of indicators generally increases with the scarcity of the chosen indicator plant. Therefore, choosing abundant plant species appear often the best solution as the resulting have a lower variability and hence enable better to detect changes of deer pressure. At low herbivore pressure, palatable species to offer quick response to the pressure variations. Palatable species are therefore reliable plant indicator especially if these is a good balance between game population and forestry. At excessive herbivore pressure, non-palatable species are preferred. In this case, the variability of ecological indicator is smaller with non palatable plant than with palatable plant. Ecological indicators of deer pressure help to understand the relationships between biodiversity, carrying capacity and deer populations. They are intended to forest managers that would like to monitor red deer pressure in regards to forest management goals and forest sustainability. [less ▲]

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See detailA study about the effects of affective valence on a source-monitoring error: cryptomnesia
Beaufort, Aline ULg; Brédart, Serge ULg; Perfect, Timothy J. et al

Poster (2013, August)

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See detailMetabolic diversity and microbial biomass in forest soils across climatic and tree species diversity gradients
Carnol, Monique ULg; Bosman, Bernard ULg; Vanoppen, Astrid et al

Poster (2013, August)

The biogeochemical cycling in forest ecosystems is highly dependent on the interactions between plants and soil. Tree species affect element cycling through deposition in throughfall, litterfall ... [more ▼]

The biogeochemical cycling in forest ecosystems is highly dependent on the interactions between plants and soil. Tree species affect element cycling through deposition in throughfall, litterfall, microbial activities in soil and rhizosphere processes. Tree species diversification has been suggested for maintaining forest ecosystem services and combining provisioning and supporting services within multifunctional and sustainable forestry. However, the understanding of the role of biodiversity in forests is unclear, in particular concerning the microbial diversity and activity in soils. Here we synthesize results from measurements of bacterial metabolic diversity and microbial biomass in soils sampled in the 209 plots of the Exploratory Platform of the FunDivEUROPE project (http://www.fundiveurope.eu/). This Exploratory Platform is a network of comparative plots of 1-5 tree species established in existing mature forest in 6 countries. These six focal regions represent important European forest types along the gradient from boreal forest to Mediterranean forest. We analysed the impact of tree species richness and the role of other controlling factors on the metabolic diversity of soil bacteria and on microbial biomass. [less ▲]

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See detailThe influence of subjective factors on the evaluation of singing voice accuracy
Larrouy, Pauline ULg; Morsomme, Dominique ULg

Poster (2013, August)

A previous study highlighted the objectivity of music experts when rating the vocal accuracy of sung performances (Larrouy-Maestri, Lévêque, Schön, Giovanni, & Morsomme, 2013). However, in an ecological ... [more ▼]

A previous study highlighted the objectivity of music experts when rating the vocal accuracy of sung performances (Larrouy-Maestri, Lévêque, Schön, Giovanni, & Morsomme, 2013). However, in an ecological context, numerous factors can influence the judges’ assessment of a music performance. This preliminary study aims to examine the effect of the music level of the performers on the evaluation of singing voice accuracy and to explore subjective factors which could influence the assessment. The same sung melody, performed by first and second year students of music conservatory (N = 31), was recorded in the context of their solfeggio examination. The jury, constituted of four music experts, was asked to rate the global pitch accuracy of each student. Two criteria (pitch interval deviation and tonal center deviation) were objectively measured and subjective data about the feeling of the students during the performance (e.g. anxiety level, enjoyment of singing) were collected through questionnaires. The results showed that the criteria used by the jury differed according to the music level of the students. Indeed, while the score of the jury correlated significantly with the vocal accuracy of the second year students, their assessment seemed more subjective concerning the first year students. Interestingly, the score of the jury was significantly correlated with the enjoyment of singing of the first year students and not with the objective measurements (pitch interval deviation and tonal center deviation) anymore. This preliminary work shows the effect of the music level of the performers on the evaluation of singing voice accuracy. Besides the educational implications of these findings, this study describes a promising method for the investigation of subjective factors, which influence the vocal assessment in an ecological context. [less ▲]

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See detailGrowth of Chlorella in vanillin enriched medium
Miazek, Krystian ULg; Goffin, Dorothée ULg; Richel, Aurore ULg

Poster (2013, August)

In this work the effect of different concentration of vanillin on the growth of Chlorella culture was evaluated. Two concentrations of vanillin: 60 mg/L and 300 mg/L in Bold Basal Medium (BBM) were tested ... [more ▼]

In this work the effect of different concentration of vanillin on the growth of Chlorella culture was evaluated. Two concentrations of vanillin: 60 mg/L and 300 mg/L in Bold Basal Medium (BBM) were tested and an inoculum from a two month Chlorella sp. (CCBA) culture was used. Vanillin at concentration of 60 mg/L showed to possess stimulating effect on Chlorella growth during 11 days of cultivation. Stimulation of Chlorella started on 3rd day of growth and was accompanied by 87% decrease of vanillin concentration within first 3 days of cultivation and its complete removal from growth media after 7 days. The acceleration of Chlorella growth in vanillin containing medium was detected due to biomass density, up to 1.2 times bigger than in the control culture, but also by measurement of chlorophyll content. Increased amount of chlorophyll content, up to 1.35 times higher than in control, was found between 4th and 11th day of cultivation. The response of Chlorella towards higher concentration of vanillin (300 mg/L) was different when compared to experiments where only 60 mg/L was used. During first 4 days of cultivation, strong inhibition of Chlorella exposed to 300 mg/L vanillin was observed and vanillin concentration maintained at the same initial concentration. During next days, a recovery effect occurred as biomass density and chlorophyll content gradually increased in comparison to the onset of growth and vanillin concentration decreased to 2 % of its initial value. Biomass density measured in Chlorella culture on 11th day was much higher than at the beginning of cultivation but still by 40% smaller than in control and by 50% smaller than in the culture growing in medium with 60 mg/L of vanillin. Chlorophyll content at the end of cultivation constituted 50% of control value and 35% of chlorophyll culture with 60 mg/L vanillin in medium. [less ▲]

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See detailSpatial analysis of bark-stripping damage by red deer in irregular hardwood forest
Lehaire, François ULg; Mercier, Grégoire; Lejeune, Philippe ULg

Poster (2013, August)

Over the past years, the population size of red deer (Cervus elaphus L.) is following an upward trend in Wallonia. This has led to an increased pressure on vegetation as well as to forest damages of ... [more ▼]

Over the past years, the population size of red deer (Cervus elaphus L.) is following an upward trend in Wallonia. This has led to an increased pressure on vegetation as well as to forest damages of greater frequency and intensity. Among these damages, bark-stripping can be especially harmful to the timber quality due to the development of rot. The impact of these populations may thus lead to a reduction in forest productivity and to economic losses. Nevertheless, these damages doesn’t depend only on the density of red deer but also on the environmental characteristics of their habitats. The main objective of this study is to perform a spatial analysis of the occurrence of bark stripping in order to identify the environmental factor that affect the occurrence of the damages in hardwood forests. The bark-stripping damages in coniferous stands are well-known due to the fact that they are relatively frequent. Such information is however unavailable for hardwood stands. The study site (6500 hectares) is located in the Ardennes in Southern Belgium (Wallonia) and is mainly composed of beech stands. We used data of inventory campaigns that were carried out for management purposes. In each sampling unit (total of 321 units), we measured different stand characteristics and, during a second phase, the bark-stripping damages. These latter measurements concerned the presence or absence of bark-stripping on each recorded stem and damage age (presence or not of a healing roll). Only trees with dbh greater than 5 cm were taken into account. All the data were collected in hardwood stands. To perform the spatial analysis, a set of environmental variables, including landscape (distances to the natural or artificial feeding points, to watering-place, to the different types of road and to the forest paths, to refuge areas for deer and to forest edges, etc.) and tree dimension variables, have been collected. The estimated red deer density was also took into account. All these variables have been included in a fixed linear model using stepwise regression. An angular transformation was applied in order to guarantee appropriate conditions of application of the linear regressions. Over one hundred variables were tested but only six of them have a significant impact on the bark-stripping rate. This model explains only 10,2% of the bark-stripping rate. Tree dimension variables explain most of the bark-stripping rate. Thus, forest structure has an important impact on the bark-stripping probability. The roads and the human activities in general can have an impact on the bark-stripping rate. These activities can disturb the red deer feeding periods during the day and lead to important bark-stripping damages. We expected to observe other variables contributing to the model such as red deer density and altitude. The absence of effect of altitude can be explained by the fact that bark-stripping of beech trees occurs mainly in summer. The scale of the study can explain the absence of red deer density. [less ▲]

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See detailWild boar movement ecology: what do we (don’t) know ?
Morelle, Kevin ULg; Prévot, Céline; Lehaire, François ULg et al

Poster (2013, August)

Although subject of many researches since decades, movement studies have been recently enhanced by the emergence of the movement ecology paradigm (Nathan 2008). Under this paradigm, Nathan et al. (2008 ... [more ▼]

Although subject of many researches since decades, movement studies have been recently enhanced by the emergence of the movement ecology paradigm (Nathan 2008). Under this paradigm, Nathan et al. (2008) proposed to break down movement of animal into four basic mechanistic components: i) internal states (motivation, physiology, why to move ?), ii) motion capacities (how to move ?), iii) navigation capacities and (when and where to move ?) and iv) external factors (physical environment and living organisms – conspecifics or not). Considering these four components of an individual’s movement, we reviewed literature dealing with wild boar (Sus scrofa L.), a species of important ecological and socio-economic concern, and tried to identify the key processes influencing this species’ movement. We conclude this review of the literature by highlighting the gaps in movement ecology of wild boar and suggesting further research directions under the light of the most recent used techniques. [less ▲]

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See detailMental Time Travel in First Degree Relatives of Schizophrenia Patients
Boulanger, Marie ULg; Wagener, Aurélie ULg; Duke, Géraldine et al

Poster (2013, July 23)

Introduction. Genetic and environmental factors are important to explain the causation of schizophrenia. The families’ studies can help us to better understand the genetic influence. Indeed, the cognitive ... [more ▼]

Introduction. Genetic and environmental factors are important to explain the causation of schizophrenia. The families’ studies can help us to better understand the genetic influence. Indeed, the cognitive deficits found in the unaffected biological relatives of schizophrenia patients parallel the deficits found in patients. These deficits might be putative endophenotypic markers of schizophrenia, ie. characteristics that mark the presence of a genetic predisposition to a certain disease or disability, in this case, the schizophrenia (Sitskoorn et al., 2004). In this way, previous studies reported that compared to healthy controls (HC), the relatives show cognitive impairments that are similar but milder degree than those of schizophrenia patients (SCh). The deficits affect cognitive functions such as verbal memory, attention and executive function; hence the interests to take into account the endophenotypic markers. To our knowledge, no study has yet assessed the abilities to mental time travel in the relatives despite that this cognitive function is impairment in SCh (Cuervo-Lombard et al., 2007; D’argembeau et al., 2008; Wood and Brewin, 2006). The mental time travel allows individuals both to retrieve past personal autobiographical information and to project into future personal events. Further, it is related to the continuity and the stability of identity, which has also been described as fragmented instable or discontinuous in SCh (Boulanger et al., submitted; deBonis et al., 1995; Nieznanski, 2004). Consequently, the ability to mental time travel could be a relevant endophenotypic marker. Method. 31 SCh, 33 relatives and 31 HC generated both ten past memories and ten future events in response to cue words from TeMA (a French version of AMT). In parallel, they completed cognitive tests, such as the Stroop Color-Word Test, the Trail Making Test, the Digit Span Backward and Forward Test (WAIS-III) and questionnaires which evaluated mood disturbances such as BDI-II and STAI-Y. Finally, participants were asked to respond to a short version of LABEL, which measured identity stability. Results. SCh showed deficits on all measures in comparison to HC. However no significant differences emerged between relatives and HC on measures of time travel. Nevertheless, differences were found for interference score (Stroop-Color-Words Test) and score on part B from TMT, as well as relatives and SCh. Discussion. Despite the fact that the majority of the relatives’ scores on different measures are not significant in comparison to HC and SCh, their results situated between the results of both groups. These results are discussed in the light of previous research. [less ▲]

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See detailDemographic trends and Streptococcus outbreaks in a synanthropic population of macaques (Macaca fascicularis), Bali (Indonesia)
Brotcorne, Fany ULg; Wandia, I. Nengah; Beudels-Jamar, Roseline et al

Poster (2013, July 22)

The sympatric relationship between humans and primates is a contemporary widespread phenomenon. Several primate species are capable for exploiting human-modified habitats in association with people, but ... [more ▼]

The sympatric relationship between humans and primates is a contemporary widespread phenomenon. Several primate species are capable for exploiting human-modified habitats in association with people, but the most successful species in South-east Asia is probably the long-tailed macaque (M. fascicularis). The low predation pressures in zones of interface and the inclusion of human food in macaques’ diet can lead to local overpopulations. On the other hand, the risk of epidemic disease is simultaneously increased by the high primate density and the proximity with human vectors. Data presented here represent 25 years-population dynamics of a long term commensal-living population of macaques in Ubud Monkey Forest (Indonesia). This population experienced a dramatic growth with an 11% annual increase rate. In June 2012, we counted 615 individuals divided in 5 groups with a very high density of 61 macaques per hectare. However, two Streptococcus outbreaks have also been reported over the same 25 years period, temporarily limiting the steep positive demographic trend of this population. The last epidemic event in July 2012 resulted in a 14% mortality affecting 3 out of 5 groups of the population. Besides the anthropic factors promoting population growth, epidemic diseases play a significant role in shaping the dynamics of this synanthropic population and could have important implications in the future both in terms of local management and local conservation status. [less ▲]

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See detailRole of non-polyQ regions on the aggregation of polyQ proteins into amyloid fibrils triggered by polyQ expansions
Huynen, Céline ULg

Poster (2013, July 22)

Ten neurodegenerative diseases, referred to as polyglutamine (polyQ) diseases, are associated with the aggregation into amyloid fibrils of ten different proteins containing a polyQ expansion higher than a ... [more ▼]

Ten neurodegenerative diseases, referred to as polyglutamine (polyQ) diseases, are associated with the aggregation into amyloid fibrils of ten different proteins containing a polyQ expansion higher than a pathological threshold comprised between 35 to 45Q (1, 2). A large body of evidence indicate that the polyQ expansion is the critical determinant for the aggregation of these polyQ proteins. The aggregation process of polyQ proteins is, however, still not well understood. To better understand this mechanism at a molecular level, we have characterized model polyQ proteins made of the β-lactamase BlaP from Bacillus licheniformis 749/C and a polyQ tract of 0 to 79Q inserted either at position 197 or position 216 of BlaP. Those chimeras recapitulate the same aggregation behaviours than that of disease-associated polyQ proteins: there is a glutamine threshold for the aggregation into amyloid fibrils and the anticipation phenomenon. Most importantly, the threshold critically depends on the structural integrity of BlaP (3) which would impose some conformational and/or sterical constraints to the polyQ tract. Moreover the position of the polyQ insertion into BlaP modifies the aggregation propensity of BlaP chimeras. The present work aims to further investigate (i) how the protein context affects the different phases of the aggregation phenomenon (i.e. the nucleation and elongation phases) and (ii) the role of the oligomers formed during the early time of the aggregation process. The techniques used are mainly (1) quartz crystal microbalance (QCM) and atomic force microscopy (AFM) to study the elongation step of amyloid fibril formation and (2) dynamic light scattering (DLS) to study the evolution of the different populations formed during the aggregation time course. The results of these experiments indicate that the native conformation of BlaP197(Gln)55 interferes mainly with the nucleation but not with the elongation step of amyloid fibril formation. Moreover, these results demonstrate that the sequences flanking the polyQ tract significantly influence its propensity to elongate amyloid fibrils. Finally, they clearly indicate that the oligomers of BlaP197(Gln)79 observed at the early stage of the aggregation process are on the pathway of amyloid fibril formation, and likely constitute the aggregation nucleus. [less ▲]

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See detailTracking the growth of Trichoderma reesei during HFBII production - CO2 -HFBII foam
Khalesi, Mohammadreza; Riveros-Galan, David; Deckers, Sylvie et al

Poster (2013, July 21)

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See detailModelling climate change impacts on key tree species used by lion tamarins in the Brazilian Atlantic Forest
Raghunathan, Poornima ULg

Poster (2013, July 21)

We used 3 IPCC climate change scenarios (A1B, A2, B1) in a dynamic vegetation model (CARAIB), to determine the potential future distribution of biomes and 75 species of trees used as food sources or ... [more ▼]

We used 3 IPCC climate change scenarios (A1B, A2, B1) in a dynamic vegetation model (CARAIB), to determine the potential future distribution of biomes and 75 species of trees used as food sources or sleeping sites by endemic primates, the golden lion tamarin (Leontopithecus rosalia) and the golden-headed lion tamarin (L. chrysomelas), in the Brazilian Atlantic Forest (BAF). Habitat conservation is a vital part of strategies to protect endangered species, and this is an approach to understand how key plant species needed for faunal survival might be affected by climate change and what changes to their distribution are likely. CARAIB computes the main physiological reaction of plants, e.g. water absorption or photosynthesis, as a response to temperature, precipitation, or CO2 partial pressure. The model accurately predicted the current distribution of BAF vegetation types and for 66% of the individual tree species with 70% agreement obtained for presence. In the simulation experiments for the future, 72 out of 75 tree species maintained more than 95% of the original distribution and all species showed a range expansion. The results suggested that the trees may benefit from an increase in temperature, if and only if soil water availability is not altered significantly, as was the case with climate simulations that were used. However, the results must be coupled with current and planned land-uses to maximise the usefulness to conservation, as the BAF is subject to many threats. [less ▲]

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See detailThe Anxiety Sensitivity in Children: Developmental Perspective
Stassart, Céline ULg; Etienne, Anne-Marie ULg

Poster (2013, July 19)

Introduction. Anxiety sensitivity (AS) is the fear of anxiety-related sensations due to beliefs that these sensations will lead to physical illness, social embarrassment, loss of control and mental ... [more ▼]

Introduction. Anxiety sensitivity (AS) is the fear of anxiety-related sensations due to beliefs that these sensations will lead to physical illness, social embarrassment, loss of control and mental incapacitation. AS plays a central role in the etiology and maintaining of fear and anxiety. This work examines the gender and age effect on the AS scores. Method. Two hundred children aged 9 to 13 years completed the Childhood Anxiety Sensitivity Index (CASI). Results. Hierarchical multiple regression analyses showed that the sex and the interaction Sex*Age explain significantly the CASI scores. The interaction indicated that girls have higher AS than boys at the age of 9, 10 and 11 but not to 12 and 13 years. Discussion. Consistent with several studies, girls have higher CASI scores than boys. However, this difference disappears at the entrance of adolescence. This developmental observation is important in a prevention perspective of AS. [less ▲]

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See detailDevelopment of Purkinje cells in the ovine brain
Salouci, Moustafa ULg; Engelen, Virginie; Gyan, Mathilda et al

Poster (2013, July 18)

Purkinje cells are involved in many vital functions within the body. Twenty ovine fetuses ranging from 2 to 5 months of gestation, two lambs in the first week after birth and three adult sheep were ... [more ▼]

Purkinje cells are involved in many vital functions within the body. Twenty ovine fetuses ranging from 2 to 5 months of gestation, two lambs in the first week after birth and three adult sheep were studied. Sections of the cerebellum were stained with haematoxylin and eosin, cresyl violet and Klu¨ver–Barrera. This study indicates that Purkinje cells began to appear after the 15th week of gestation. There were varying degrees of development of Purkinje cells in different zones of the cerebellum. Our findings in sheep fetuses suggest that the maturation of Purkinje cells starts in the caudal regions of the cerebellum and that the process begins in the vermis before it does in the cerebellar hemispheres. The alignment of Purkinje cells was found to be very regular in the caudal regions of the cerebellum. A partial absence of Purkinje cells in the rostral regions of the cerebellum was observed in both sheep fetuses and adult sheep. In the first post-natal week, some ectopic Purkinje cells were found in the white matter of the cerebellum. [less ▲]

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See detailGovernance in Japan and Belgium: Building on Experiments with Technology Assessment and TA-like Activities
Van Oudheusden, Michiel ULg; Yoshizawa, Go

Poster (2013, July 15)

This poster presents a bilateral Belgian-Japanese research study that probes the direction and quality of science and technology governance within the context of new knowledge production and responsible ... [more ▼]

This poster presents a bilateral Belgian-Japanese research study that probes the direction and quality of science and technology governance within the context of new knowledge production and responsible innovation. Drawing on recent experiences with technology assessment (TA) and TA-like activities in the regions of Flanders and Wallonia (Belgium) and the country of Japan, it asks how future-oriented science and technology governance processes are locally enacted and how they compare. Four research objectives are discerned: 1. To describe how TA concepts and practices, as well as related TA activities, have emerged in Japan, Wallonia, and Flanders since the 1960s-70s, and in what particular forms. 2. To describe how TA has evolved with, sustained, and/or countered, science, technology, and innovation policies on the regional, national, and international level. 3. To compare and contrast how TA is, or is not, institutionalized in the countries and regions, notably by taking into account initiatives to initiate or abolish parliamentary TA forms. 4. To situate the processes that are discerned through empirical analysis within a broader theory of, and movement towards anticipatory governance, and to assess the potential of TA of enhancing novel governance forms. The poster situates science, technology, and innovation policies in Japan and Belgium within the global shift towards a knowledge-based economy and the emergence of new science policy regimes, such as “strategic science” (Rip, 2002). Building on several TA case examples, it explains how the need for TA in science and technology emerges and is developed within distinctly different innovation contexts. The poster describes the project’s methodologies, working plan, and expected results, and provides suggestions for rendering comparative TA analysis useful to science policymakers and innovation actors, as well as to science and technology studies scholars. [less ▲]

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See detailTowards the first transmission spectrum of a gas giant transiting an M-dwarf
Delrez, Laetitia ULg; Gillon, Michaël ULg; Lendl, M. et al

Poster (2013, July 15)

At the forefront of comparative exoplanetology, the atmospheric characterization of transiting exoplanets is revealing the intimate nature of these new worlds. In this exciting context, we are currently ... [more ▼]

At the forefront of comparative exoplanetology, the atmospheric characterization of transiting exoplanets is revealing the intimate nature of these new worlds. In this exciting context, we are currently conducting a VLT observing campaign on a rare exoplanet specimen, WASP-80b, a gas giant in close orbit around a bright nearby M-dwarf. Even if this planet belongs to the hot-Jupiter population, it is actually more ‘warm’ than ‘hot’ with an estimated equilibrium temperature of only 800K. We present here some preliminary results of this program which consists in monitoring four transits of WASP-80b with the FORS2 instrument in multi-object spectroscopic mode in ESO phase 91. Through this approach, our goal is to precisely measure the transmission spectrum of the planet between 740 and 1070 nm in order to constrain the thermal structure and scacering properties of the planetary atmosphere. Furthermore, we will use the water features located around 950 nm to constrain the water mixing ratio in the atmosphere of this peculiar hot Jupiter. [less ▲]

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See detailConcomitant inhibition of class I HDAC and COX-2 exerts a antitumor effect in a human pancreatic cancer model
Gonzalez, Arnaud ULg; Peixoto, Paul ULg; Turtoi, Andrei ULg et al

Poster (2013, July 11)

- Introduction : Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer death in developed countries. Early-stage pancreatic cancer is usually clinically silent, and disease only ... [more ▼]

- Introduction : Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer death in developed countries. Early-stage pancreatic cancer is usually clinically silent, and disease only becomes apparent after the tumor invades surrounding tissues or metastatises to distant organs. Moreover, the current chemotherapeutic treatments have no or few effects on this type of cancer, increasing only slightly the median survival of the patients. The survival rate at 5-years is only 3%. There is a need to develop new effective therapies for PDAC patients together with a robust and fast in vivo model allowing drug screening. In this study, We tested whether the combined inhibition of cyclooxygenase-2 (COX-2) and class I histone deacetylase (HDAC) may result in a better control of PDAC. We improved the formation of pancreatic tumor on Chorioallantoic membrane (CAM), an alternative to murine model. - Methods : The impact of the concomitant HDAC and COX-2 inhibition on cell growth, apoptosis and cell cycle was assessed in vitro on human pancreas BxPC-3 cells treated with chemical inhibitors (SAHA, MS-275 and celecoxib) or HDAC1/3/7 siRNA. To test the potential antitumoral activity of this combination in vivo, we improved, characterized and used model of pancreas tumors growing on chick chorioallantoic membrane. - Results : The inhibition of HDAC1/3 by SiRNA or MS-275 treatment reduced significantly the growth of BxPC-3 cells in vitro. Furthermore, we showed by QPCR and immunoblotting that both HDAC1 and HDAC3 inhibition induced the expression of COX-2 at least via the NF-kB pathway. Based on this observation, we decided to test the effect of MS-275 combined with celecoxib a COX-2 inhibitor. This combination was more effective then either drug used alone to reduce the growth of BxPC-3 cells. By FACS analysis we showed that MS-275/celecoxib combination decreased significantly the proportion of cells in S phase and increased significantly and drastically the proportion in G0/G1 at 24, 48 and 72h. By immunobloting this GO/G1 arrest was confirmed by accumulation of cell cycle repressors (P21, P27) and disappearance of hyper phosphorylated form of RB protein. Following a procedure development, we produced on CAM 60 mm3 functionally vascularized tumors mimicking human pancreatic tumors on CAM model. The clinical relevance of this model is supported by the CK7+/CK19+/CK20-/CEA+/Ki67+/CD56- immunolabeling. Recently we have discovered several novel biomarkers of human PDAC: MYOF, TGFBI, LTBP2. These antigens were expressed in tumors grown on CAM, reaffirming its clinical relevance. The concept of the co-treatment by MS-275 and celecoxib was validated using this model. We showed that celecoxib alone did not significantly reduce tumor growth. MS-275 alone decreased tumor growth by 50% and combination of celecoxib and MS-275 stalled entirely the tumor growth. - Conclusions : Our data demonstrate a significant synergic anti-tumoral action of HDAC and COX-2 inhibitors, which set a basis for the development of potentially effective new combinatory therapies for PDAC patients. [less ▲]

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See detailGenetic analysis of longitudinal measurements of feed intake in Piétrain sire lines
Dufrasne, Marie ULg; Jaspart, Véronique; Wavreille, José et al

Poster (2013, July 10)

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See detailMetallo-supramolecular micellar gels: a structural study
Mugemana, Clément; Joset, Arnaud ULg; Guillet, Pierre et al

Poster (2013, July 10)

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See detailFirst spike latency sensitivity of spiking neuron models
Trotta, Laura ULg; Franci, Alessio ULg; Sepulchre, Rodolphe ULg

Poster (2013, July 08)

First spike latency is the long-lasting period preceding the first spike of a neuron submitted to a super-threshold stimulus. It has been suggested that this latency could code for stimulus recognition in ... [more ▼]

First spike latency is the long-lasting period preceding the first spike of a neuron submitted to a super-threshold stimulus. It has been suggested that this latency could code for stimulus recognition in several sensory systems. To encode information reliably, first spike latency should be sensitive to sensory inputs but robust to external perturbations. This paper studies the robustness of the first spike latency in spiking neuron models. We show the interplay between bistability, first spike latency and a type of neuronal excitability called regenerative excitability. [less ▲]

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