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See detailEmulation of the MBM-MEDUSA model: exploring the sea level and the basin-to-shelf transfer influence on the system dynamics
Ermakov, Ilya; Munhoven, Guy ULg; Crucifix, Michel

Poster (2013, April 12)

Complex climate models require high computational burden. However, computational limitations may be avoided by using emulators. In this work we present several approaches for dynamical emulation (also ... [more ▼]

Complex climate models require high computational burden. However, computational limitations may be avoided by using emulators. In this work we present several approaches for dynamical emulation (also called metamodelling) of the Multi-Box Model (MBM) coupled to the Model of Early Diagenesis in the Upper Sediment A (MEDUSA) that simulates the carbon cycle of the ocean and atmosphere [1]. We consider two experiments performed on the MBM-MEDUSA that explore the Basin-to-Shelf Transfer (BST) dynamics. In both experiments the sea level is varied according to a paleo sea level reconstruction. Such experiments are interesting because the BST is an important cause of the CO2 variation and the dynamics is potentially nonlinear. The output that we are interested in is the variation of the carbon dioxide partial pressure in the atmosphere over the Pleistocene. The first experiment considers that the BST is fixed constant during the simulation. In the second experiment the BST is interactively adjusted according to the sea level, since the sea level is the primary control of the growth and decay of coral reefs and other shelf carbon reservoirs. The main aim of the present contribution is to create a metamodel of the MBM-MEDUSA using the Dynamic Emulation Modelling methodology [2] and compare the results obtained using linear and non-linear methods. The first step in the emulation methodology used in this work is to identify the structure of the metamodel. In order to select an optimal approach for emulation we compare the results of identification obtained by the simple linear and more complex nonlinear models. In order to identify the metamodel in the first experiment the simple linear regression and the least-squares method is sufficient to obtain a 99,9% fit between the temporal outputs of the model and the metamodel. For the second experiment the MBM’s output is highly nonlinear. In this case we apply nonlinear models, such as, NARX, Hammerstein model, and an ’ad-hoc’ switching model. After the identification we perform the parameter mapping using spline interpolation and validate the emulator on a new set of parameters. [less ▲]

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See detailCharacteristics and age of an uplift signal in the Biga Peninsula (NW Turkey) from a mix of geomorphic indices
Demoulin, Alain ULg; Bayer Altin, Turkan; Beckers, Arnaud ULg

Poster (2013, April 11)

Situated in the area where the western end of the North Anatolian Fault Zone meets the extensional domain of the North Aegean Sea, the Kazdag Mountain range (Biga Peninsula, NW Turkey) is known to have ... [more ▼]

Situated in the area where the western end of the North Anatolian Fault Zone meets the extensional domain of the North Aegean Sea, the Kazdag Mountain range (Biga Peninsula, NW Turkey) is known to have undergone Plio-Quaternary uplift. However, no detailed chronology of this presumably ongoing uplift phase was so far available. In order to obtain a first-order estimate of the time of the last tectonic perturbation (uplift rate change) in the region, we performed a morphometric study of the fluvial landscape at the scale of the Biga Peninsula, coupling the recently developed R/SR analysis of the drainage network with concavity and steepness measures of a set of 29 rivers of all sizes. Defined as the ratio of two-by-two differences between hypsometric integrals describing respectively a catchment’s topography, its drainage network "composite profile" and the trunk stream profile, the R metric is a measure of the catchment’s incision response to a relative base level lowering. The SR index is then simply the slope of the regional relation R = f(ln A), a feature characteristic of the time elapsed since uplift caused an erosion wave to propagate in the drainage system. We obtained a SR value of 0.324±0.035 that, according to the t = f(SR) relation established by Demoulin (2012), yields an age range of 0.54-1.29 Ma and a most probable value of 0.82 Ma for the time of the last uplift signal in the Biga Peninsula. We also carried out an analysis of knickpoint migration in a subset of rivers, modelling their propagation by the stream power law under different assumed ages so as to compare the obtained values of the K coefficient with values mentioned in the literature. The positive results of this analysis, yielding realistic K values for ages around 0.8 Ma, lend independent support to our morphometric estimate of the uplift time, moreover corroborated by published observations suggesting basin inversion of the Bayramiç and Çanakkale depressions at the same epoch. We relate this episode of increased uplift rate to the early-to-mid Pleistocene tectonic transition identified in the Eastern Mediterranean realm by Schattner (2010) and marked by a brief compressional episode. Finally, while the dependence of river profile concavity on basin size confirms that the landscape of the peninsula is still in a transient state, the spatial distribution of profile steepness values characterized by higher values for streams flowing down from the Kazdag massif shows that the latter undergoes higher uplift rates than the rest of the peninsula. This indicates that, after the regional Middle Pleistocene episode of accelerated uplift had come to an end, a local component of uplift persisted associated with either transpressive conditions along SW-trending segments of the North Anatolian Shear Zone or normal faulting along the southern border of the massif. References Demoulin A., 2012. Morphometric dating of the fluvial landscape response to a tectonic perturbation. Geoph. Res. Lett. 39, L15402, doi:10.1029/2012GL052201. Schattner U., 2010. What triggered the early-to-mid Pleistocene tectonic transition across the entire eastern Mediterranean? Earth Planet. Sci. Lett. 289, 539-548. [less ▲]

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See detailValidation of the Structural-Thermal-Model of the Small Earth Observation Satellite Flying Laptop
Steinmetz, Fabian; Lengowski, Michael; Winter, Daniel et al

Poster (2013, April 10)

Thorough thermal design and testing is compulsory for every satellite mission. A well-known thermal behavior of the entire satellite system is therefore indispensable and needs to be verified during the ... [more ▼]

Thorough thermal design and testing is compulsory for every satellite mission. A well-known thermal behavior of the entire satellite system is therefore indispensable and needs to be verified during the spacecraft development. A Structural-Thermal-Model (STM) was constructed for the Flying Laptop, a satellite currently being developed at the Institute of Space Systems (IRS) of the University of Stuttgart, which enables the validation of mechanical and thermal simulations for the satellite’s Flight-Model. The STM was vibration and thermal-vacuum tested at the Centre Spatial Liège (CSL). This paper will de-scribe the design and construction of the STM as well as the facilities and test equipment used for the tests. Conclusions will be drawn from the actual test results. [less ▲]

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See detailEvolution of methanol (CH3OH) above the Jungfraujoch station (46.5°N) : Variability, seasonal modulation and long-term trend.
Bader, Whitney ULg; Mahieu, Emmanuel ULg; Lejeune, Bernard ULg et al

Poster (2013, April 09)

Methanol (CH3OH) is the second most abundant organic compound in the Earth’s atmosphere with concentrations close to a few ppbv, after methane, despite a short lifetime of a few days (Jacob et al., 2005 ... [more ▼]

Methanol (CH3OH) is the second most abundant organic compound in the Earth’s atmosphere with concentrations close to a few ppbv, after methane, despite a short lifetime of a few days (Jacob et al., 2005). Natural sources of CH3OH include plant growth, oceans, decomposition of plant matter, oxidation of methane and other VOCs,. . . while anthropogenic sources are from vehicles, industry,. . . biomass burning completes the emission budget. The main sink is the oxidation by hydroxyl radical, leading to the formation of carbon monoxide (CO) and formaldehyde (H2CO). The retrieval of methanol is very challenging due to the presence of strong absorption of ozone and its isotopologues in addition to water vapour and carbon dioxide in the region of the selected strong nu8 band of CH3OH. First retrievals from satellite observations using the Atmospheric Chemistry Experiment infrared Fourier Transform Spectrometer (ACE-FTS) on board the SCISAT satellite have been performed by Dufour et al. (2007 and references therein) using a spectral interval going from 995.5 to 1008.3 cm-1. In 2009, first retrievals from a ground-based FTS, using spectra recorded at Kitt Peak (31.9°N) and a window going from 992 to 999 cm-1 have been reported by Rinsland et al. (2009), followed by Vigouroux et al. (2012 and references therein) who used yet another spectral interval going from 1029 to 1037cm-1. From those former retrieval strategies and also considering the Mahieu et al. (2012) contribution, we redefined our spectral intervals to maximize the information content. Indeed, our first window, starting from 992 to 1008.3 cm-1, is issued from the merge of Rinsland et al. and Dufour et al. windows while our second, going from 1029 to 1037 cm-1, is the one used by Vigouroux et al.With this new combination of windows, we were able to enlarge the range of zenith angles providing robust results while maintaining good correlation between our two windows; this also resulted in an improvement of the fitting residuals and of the information content. We used the 2008 HITRAN compilation (Rothman et al., 2009) for spectroscopic parameters. However, systematic residuals still remain in the 1033 cm-1 region which are attributed to unsatisfactory line parameters for methanol. New cross sections recorded at the Molecular Spectroscopy Facility of the Rutherford Appleton Laboratory (Harrison et al. 2012) and calibrated in intensity by using the reference spectra from the Pacific Northwest National Laboratory (PNNL) IR database will be tested as soon as converted into pseudolines. In this work, we will present the first long-term time series of methanol total columns, resulting from the implementation of our new retrieval strategy. All retrievals have been performed with the SFIT2 algorithm (v 3.91) (Rinsland et al., 1998) using a series of about 7 000 spectra recorded between 1995 and 2012, with zenith angles between 60 and 85°. These solar absorption observations have been recorded with a high-resolution FTIR Bruker 120HR instrument, at the high altitude station of the Jungfraujoch (46.5°N, 8°E, 3580 m asl), within the framework of the Network for the Detection of Atmospheric Composition Change (NDACC, visit http://www.ndacc.org). [less ▲]

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See detailTemporal variability of nitrous oxide fluxes from a fertilized grassland in Belgium: preliminary results from dynamic closed chambers.
Beekkerk van Ruth, Jöran ULg; Moureaux, Christine ULg; Degré, Aurore ULg et al

Poster (2013, April 09)

Presentation of preliminary results from N2O measurements over a grassland using dynamic closed chambers. See attached folders for more detail.

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See detailSoil respiration partitioning and its components in the total agro-ecosystem respiration
Delogu, Emilie; Le Dantec, Valérie; Mordelet, Patrick et al

Poster (2013, April 09)

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See detailTEMPORAL VARIABILITY OF N2O FLUXES FROM A FERTILIZED GRASSLAND: PRELIMINARY RESULTS FROM DYNAMIC CLOSED CHAMBERS
Beekkerk van Ruth, Jöran ULg; Moureaux, Christine ULg; Degré, Aurore ULg et al

Poster (2013, April 09)

This work presents preliminary results of nitrous oxide (N2O) fluxes measured by dynamic closed chambers from a fertilized grassland grazed by the Belgian Blue breed of cattle. It is part of a project ... [more ▼]

This work presents preliminary results of nitrous oxide (N2O) fluxes measured by dynamic closed chambers from a fertilized grassland grazed by the Belgian Blue breed of cattle. It is part of a project funded by the public service of Wallonia (SPW-DGARNE), whose objectives are to make a carbon/CO2 balance of the grassland (Jérôme et al., 2013) and to quantify CH4 (Dumortier et al., 2013) and N2O fluxes. The site is located in Dorinne (Dorinne Terrestrial Observatory), Belgium (50° 18’ 44” N; 4° 58’ 07” E; 248 m al.). It is a permanent grassland of ca. 4.2 ha with a moderate slope of 1 to 2 %. Mineral fertilisation took place in March and May 2012. Two cylindrical chambers of 19,2 cm diameter and 11,5 cm height were placed inside a protected area around a micrometeorological station. An infrared gas analyser (Thermofischer 46i) was used in order to measure the N2O concentrations inside of the chambers, closed by automatically controlled lids and ventilated by a constant air flow of 1liter/min. These devices were completed by adjacent soil humidity and temperature sensors. The first measurement campaign took place during June and July 2012. The chambers were installed in the field and N2O fluxes were followed without manipulation. N2O fluxes were characterised by a background emission (between 2 and 10 ngN.m2s􀀀1) on which intense but time limited peaks (between 50 and 300 ngN.m2s􀀀1) superimposed. Peaks were found to be mainly linked to fertilisation and driven by precipitation. Background fluxes were found to correlate positively with soil temperature. Secondly, a manipulation experiment took place in November 2012: two different fertilizer treatments were applied to the chambers. Doses of respectively 100 and 200 kg N/ha of ammonium nitrate were sprayed in the chambers (equivalent to a 8mmprecipitation). N2O fluxes peaked shortly after fertiliser application (respectively 300 and 550 ngN.m2s􀀀1), as well as after a posterior rain event (respectively 800 and 1500 ngN.m2s􀀀1). The peak dynamics suggests a complex interaction between soil humidity and nitrogen availability, which is under study. Dumortier et al., Geophysical Research Abstracts, Vol. 15, EGU2013-2083-1, 2013 Jérôme et al., Geophysical Research Abstracts Vol. 15, EGU2013-6989, 2013 [less ▲]

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See detailImpact of grazing on carbon balance of an intensively grazed grassland in Belgium
Jerome, Elisabeth ULg; Beckers, Yves ULg; Beekkerk van Ruth, Jöran ULg et al

Poster (2013, April 09)

This work analyzes the impact of grazing on the carbon balance of a grassland grazed by the Belgian Blue breed of cattle. The research was run at the Dorinne terrestrial observatory (DTO). The ... [more ▼]

This work analyzes the impact of grazing on the carbon balance of a grassland grazed by the Belgian Blue breed of cattle. The research was run at the Dorinne terrestrial observatory (DTO). The experimental site is a permanent grassland of ca. 4.2 ha located in the Belgian Condroz (50° 18’ 44’’ N; 4° 58’ 07’’ E; 248 m asl.). Other studies are conducted at the DTO including measurements of methane (CH4) and nitrous oxide fluxes (Dumortier et al., Geophysical Research Abstracts, Vol. 15, EGU2013-2083-1, 2013; Beekkerk van Ruth et al., Geophysical Research Abstracts, Vol. 15, EGU2013-3211, 2013, respectively). Grassland carbon budget (Net Biome Productivity, NBP) was calculated from Net Ecosystem Exchange (NEE) measured by eddy covariance by taking imports and exports of organic C and losses of carbon as CH4 into account (Soussana et al., 2010). After 2 years of measurements (May 2010 - May 2012), the grassland behaved on average as a CO2 source (NEE = 73 ±31 g C m-2 y-1). After inclusion of all the C inputs and outputs the site was closed to equilibrium (NBP = 23 ±34 g C m-2 y-1). To analyze the impact of grazing on CO2 fluxes, we studied the temporal evolution of gross maximal photosynthetic capacity GPPmax and dark respiration Rd (deduced from the response of daytime fluxes to radiation over 5-day windows). We calculated GPPmax and Rd variation between the end and the beginning of grazing or non-grazing periods (∆GPPmax and ∆Rd, respectively). We observed a significant decrease of GPPmax during grazing periods and measured a ∆GPPmax dependence on the average stocking rate. This allows us to quantify the assimilation reduction due to grass consumption by cattle. On the contrary, no Rd decrease was observed during grazing periods. Moreover, we found that cumulated monthly NEE increased significantly with the average stocking rate. In addition, a confinement experiment was carried out in order to analyze livestock contribution to Total Ecosystem Respiration. 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). Results showed that CO2 fluxes were significantly higher when cattle were on the plot. Livestock contribution estimation to CO2 fluxes was on average 6.6 µmol m-2 s-1. [less ▲]

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See detailModeling soil respiration in wheat fields
Delogu, Emilie; Le Dantec, Valérie; Mordelet, Patrick et al

Poster (2013, April 09)

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See detailDeciphering human-climate interactions in ombrotrophic peat record : REE, Nd and Pb isotope signatures of dust supplies over the last 2500 years (Misten bog, Belgium)
Fagel, Nathalie ULg; Allan, Mouhamd ULg; le roux, Gael et al

Poster (2013, April 08)

A core of 173 cm of ombrotrophic Misten peat bog from the Hautes-Fagnes Plateau in Eastern Belgium provides a record of Rare Earth Elements (REE) deposition allowing to trace dust fluxes in West Europe ... [more ▼]

A core of 173 cm of ombrotrophic Misten peat bog from the Hautes-Fagnes Plateau in Eastern Belgium provides a record of Rare Earth Elements (REE) deposition allowing to trace dust fluxes in West Europe during the historical record (last 2500 years). REE and lithogenic element analyses, as well as the Nd isotopes, were performed by HR-ICP-MS and MC-ICP-MS, respectively in peat layers dated by 210Pb and 14C. The parallel variations of REE concentration with lithogenic conservative elements confirms that REE are immobile in the studied peat bog and can be used as tracers of dust deposition. Dust fluxes show pronounced increase at BC300, AD600, 1000AD,1200AD and from 1700AD, recording either influence of human activities (regional erosion due to forest clearing and soil cultivation activities) or local and regional climate changes. Using Nd isotope allows to decipher between local and distal causes. The ENd variability (-13 to -9) is interpreted by a mixing between dust sources fromlocal soils and desert particles. Three periods characterised by dominant-distal sources (at 320AD, 1000 AD and 1700AD) are consistent with local wetter intervals as indicated by lower humi[U+FB01]cation degree. Local erosion prevails durier drier (higher humification) intervals (-100AD, 600AD). On a global scale more distal supplies are driven during colder periods, in particular Oort and Maunder minima. Combining geochemical elementary content and isotope data in ombrotrophic peat allows to decipher between dust flux changes related to human and climate forcing. [less ▲]

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See detailAmphiphilic structure-surface property relationships of monosaccharide-based surfactants
Razafindralambo, Hary ULg; Nicks, Francois ULg; Richard, Gaetan ULg et al

Poster (2013, April 08)

A set of monosaccharide-based renewable surfactants has been prepared, structurally checked, and systematically screened for different activities and functionalities. These compounds vary in the polar ... [more ▼]

A set of monosaccharide-based renewable surfactants has been prepared, structurally checked, and systematically screened for different activities and functionalities. These compounds vary in the polar head group, linker, and hydrophobic tail. Beyond the goal to find out the most potential valuable surfactants for each measurement, relationships between chemical structure, basic properties, and functionalities have been examined by comparing compounds differing in a single structural variable. In this paper, we show and explain the impact of the anomeric alpha or bêta, neutral or acid sugar derivatives, equatorial or axial position of hydroxyl group, alkyl chain substitute attachment position, number, and length on surface properties of sugar-based surfactants. [less ▲]

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See detailVariability of North Sea pH and CO2 pumping in response to North Atlantic Oscillation forcing
Salt, L; Thomas, H; Prowe, F et al

Poster (2013, April 07)

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See detailFrom a source to a sink: the role of biological activities on atmospheric CO2 exchange along the river-ocean continuum
Gypens, N; Passy, P; Lancelot, C et al

Poster (2013, April 07)

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See detailThe influence of biogeochemical processes on the pH dynamics in the seasonally hypoxic saline Lake Grevelingen
Hagens, M; Slomp, C; Meysman, F et al

Poster (2013, April 07)

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See detailDynamic of seed dispersal by large frugivores in a forest-savanna mosaic subject to anthropic pressure in Western D.R. Congo
Trolliet, Franck ULg; Serckx, Adeline; Huynen, Marie-Claude ULg et al

Poster (2013, April 05)

The Western Congolian forest-savanna mosaic is an ecotone subject to anthropogenic as well as natural fragmentation. Its forests have thus a considerable proportion of edges. This vegetation structure is ... [more ▼]

The Western Congolian forest-savanna mosaic is an ecotone subject to anthropogenic as well as natural fragmentation. Its forests have thus a considerable proportion of edges. This vegetation structure is likely to impact animal and plant communities and its dynamics such as animal mediated seed dispersal. Synergetically, activities such as bush meat hunting deplete large frugivores populations and thus decrease recruitment potential of the plants they disperse. Indeed, zoochory is known to be of great importance for tropical forests and a number of studies proved that large-seeded tree species closely depend on large frugivores for their regeneration. In such a context, we aim to understand how forest edges affect the dynamics of seed dispersal. More precisely, we wonder if the interactions between large seeds and their dispersers and predators are affected when closer to edges and how this can impact plant regeneration capacity. Also, we wonder if the dispersal and regeneration of large-seeded tree species depend on a few disproportionally important frugivores species. Bonobos, Pan paniscus, are among the largest frugivores left in the area and thus likely to be disproportionally important seed dispersers, though, their role as seed dispersers has yet been little investigated. We thus focus on the qualitative role for seed dispersal of the potentially keystone and umbrella ape species, the bonobo. To answer those questions, we study the main steps characteristics of large-seeded tree species regeneration process; namely quantitative seed dispersal, seed deposition pattern, germination capacity after transit in frugivore’s gut and, seed and seedling fate. By studying five different tree species at varying distances from forest edge, we aim to drive an inter-species comparison and to highlight the effect of forest edge on the regeneration process. We first quantify the seed production for each tree species and then evaluate the quantitative capacity of seed dispersal. By combining direct focal observations and camera trapping, we are able to highlight variations in composition of dispersers community and their respective contribution to seed dispersal. A literature review on each disperser species’ seed retention time and habitat use will allow the computation of the seed dispersal kernels. We will also evaluate the effect of seed ingestion by the bonobo on its germination capacity: seeds will be collected from dung to evaluate the effect of seed ingestion on the rate and velocity of germination. Finally, we will study the predation pressure exerted on dispersed and non-dispersed seeds and seedlings by setting up two sets of seeds below the canopy of parent trees and away from any conspecific trees. One set will be dispersed unprotected to seed predators; another one will be enclosed in a cage and permit seeds to germinate, allowing us to evaluate the herbivores pressure on seedlings. [less ▲]

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See detailResearch on durable junction of multimaterials
Lecomte-Beckers, Jacqueline ULg; Lecomte, Jacky; Gerlach, Nathalie ULg et al

Poster (2013, April 04)

This collective project aimed to assess the potential of adhesive bonding in various applications in the field of building construction. This evaluation takes into account technical, economical and ... [more ▼]

This collective project aimed to assess the potential of adhesive bonding in various applications in the field of building construction. This evaluation takes into account technical, economical and ecological aspects and provides a methodology that can be easily transferred to other applications. [less ▲]

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See detailA multiscale model of the influence of oxygen during bone fracture healing.
Carlier, Aurélie ULg; Geris, Liesbet ULg; Van Oosterwyck, Hans

Poster (2013, April 03)

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See detailExtensions of Superalgebras of Krichever-Novikov type
Kreusch, Marie ULg

Poster (2013, April)

An explicit construction of central extensions of Lie superalgebras of Krichever-Novikov type is given. In the case of Jordan superalgebras related to the superalgebras of Krichever-Novikov type we ... [more ▼]

An explicit construction of central extensions of Lie superalgebras of Krichever-Novikov type is given. In the case of Jordan superalgebras related to the superalgebras of Krichever-Novikov type we calculate a 1-cocycle with coefficients in the dual space. [less ▲]

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See detailThermal adaptation of the ribosomal chaperone trigger factor
Godin, Amandine ULg

Poster (2013, April)

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See detailEstimating Antarctic ice sheet surface mass balance contribution to future sea level rise using the regional atmospheric climate model MAR
Agosta, Cécile ULg; Fettweis, Xavier ULg; Gallée, Hubert

Poster (2013, April)

We report future projections of Surface Mass Balance (SMB) over the Antarctic ice sheet obtained with the regional climate model MAR, for different warming scenarios. MAR forcing is carefully selected ... [more ▼]

We report future projections of Surface Mass Balance (SMB) over the Antarctic ice sheet obtained with the regional climate model MAR, for different warming scenarios. MAR forcing is carefully selected among the CMIP5 GCMs panel according to its ability to simulate the current climate over Antarctica. MAR includes blowing snow modeling, an important process in Antarctica. [less ▲]

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See detailThe multiple SEA method: a method to synthesize Pt/carbon xerogel catalysts for Proton Exchange Membrane Fuel Cells (PEMFC)
Zubiaur, Anthony ULg; Chatenet, Marian; Maillard, Frédéric et al

Poster (2013, April)

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See detailOzone tropospheric and stratospheric trends (1995-2012) at six ground-based FTIR stations (28°N to 79°N)
Vigouroux, Corinne; De Mazière, Martine; Demoulin, Philippe ULg et al

Poster (2013, April)

In the frame of the Network for the Detection of Atmospheric Composition Change (NDACC), contributing ground-based stations have joined their efforts to homogenize and optimize the retrievals of ozone ... [more ▼]

In the frame of the Network for the Detection of Atmospheric Composition Change (NDACC), contributing ground-based stations have joined their efforts to homogenize and optimize the retrievals of ozone profiles from FTIR (Fourier transform infrared) solar absorption spectra. Using the optimal estimation method, distinct vertical information can be obtained in four layers: ground-10 km, 10-18 km, 18-27 km, and 27-42 km, in addition to total column amounts. In a previous study, Vigouroux et al. (2008) applied a bootstrap resampling method to determine the trends of the ozone total and four partial columns, over the period 1995-2004 at Western European stations. The updated trends for the period 1995-2009 have been published in the WMO 2010 report. Here, we present the updated trends and their uncertainties, for the 1995-2012 period, for the different altitude ranges, above five European stations (28°N-79°N) and above the station Thule, Greenland (77°N). In this work, the trends have been estimated using a multiple regression model including some explanatory variables responsible for the ozone variability, such as the Quasi Biennial Oscillation (QBO), the solar flux, the Arctic Oscillation (AO) or El Niño-Southern Oscillation (ENSO). A major result is the significant positive trend of ozone in the upper stratosphere, observed at the Jungfraujoch (47°N), which is a typical mid-latitude site, as well as at the high latitude stations. This positive trend in the upper stratosphere at Jungfraujoch provides a sign of ozone recovery at mid-latitudes. [less ▲]

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See detailStables isotopes in the fin whale Balaenoptera physalus from the Mediterranean Sea: implications for management and conservation
Das, Krishna ULg; Lepoint, Gilles ULg; Michel, Loïc ULg et al

Poster (2013, April)

The fin whale (Balaenoptera physalus) is the commonest large whale species in the Mediterranean Sea, found mostly over deep, offshore waters of the western and central portion of the region. This whale is ... [more ▼]

The fin whale (Balaenoptera physalus) is the commonest large whale species in the Mediterranean Sea, found mostly over deep, offshore waters of the western and central portion of the region. This whale is known to feed mainly on krill in contrast to its Atlantic counterpart, displaying a more diversified diet. δ13C and δ15N values were analysed by IR-MS (Isoprime 100) coupled to an N-C-S elemental analyser (Vario MICRO Cube, Elementar) in 113 skin biopsies from Mediterranean fin whales sampled in 2010 and 2011 during WWF campaign at sea. A lipid normalization equation was applied (adapted from Post al. 2007) because the measured C:N ratio was > 3.5. Normalized δ13C and δ15N values ranged from -20.3 to -17.3 ‰ and from 5.9 to 8.9 ‰, respectively. These values are in good agreement with those collected previously on baleen plates from Mediterranean fin whales (Bentaleb et al., 2011). A mean enrichment of 3.4 ‰ was observed between δ15N values measured in fin whale skin biopsies and Mediterranean krill (Meganyctiphanes norvegica) confirming the importance of the krill as a major food source. The narrow width of the isotopic niche of the Mediterranean fin whale (evaluated by SIBER Stable Isotope Bayesian Ellipses) compared to the Atlantic fin whale (Ryan et al. 2012) raises many concerns in the context of global changes and long-term consequences. One could expect that species displaying narrow niches would be more susceptible to ecosystem fragmentation and other anthropogenic impacts. [less ▲]

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See detailAnalytical evaluation of virgin olive oils produced from three varieties Koroneiki , Arbequina and Arbosana grown in east of Morocco
Mansouri, F.; Ben Moumen, A.; Lopez, G. et al

Poster (2013, April)

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See detailComparative study of four safflower oils (Carthamus tinctorius) varieties grown in eastern of Morocco
Ben Moumen, A.; Mansouri, F.; Zraibi, L. et al

Poster (2013, April)

Safflower (Carthamus tinctorius) is an oilseed crop, which, for many years, has been grown on a relatively small scale in parts of North Africa and Middle East (Purdy and al., 1959).

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See detailRelation entre composition floristique et accumulation de biomasse dans deux types de forêts de la Réserve de Biosphère du Dja (Cameroun)
Djuikouo, Marie Noel K.; Doucet, Jean-Louis ULg; Nguembou, Charlemagne K. et al

Poster (2013, April)

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See detailInformal caregiver involvement in innovative home care projects in Belgium
Lopez Hartmann; Van Durme, Thérèse; Maggi, Patrick ULg et al

Poster (2013, April)

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Peer Reviewed
See detailHigh-resolution modelling of the Antarctic surface mass balance, application for the 20th, 21st and 22nd centuries
Agosta, Cécile ULg; Favier, Vincent; Krinner, Gerhard et al

Poster (2013, April)

Although areas below 2000 m above sea level (a.s.l.) cover 40% of the Antarctic grounded ice-sheet, they represent about 75% of the surface mass balance (SMB) of the continent. Because the topography is ... [more ▼]

Although areas below 2000 m above sea level (a.s.l.) cover 40% of the Antarctic grounded ice-sheet, they represent about 75% of the surface mass balance (SMB) of the continent. Because the topography is complex in many of these regions, SMB modelling is highly dependent on resolution, and studying the impact of Antarctica on the fu- ture rise in sea level requires high resolution physical approaches. We have developed a new, low time consuming, physical downscaling model for high-resolution (15 km) long-term SMB projections. Here, we present results of our SMHiL (surface mass balance high-resolution downscaling) model, which was forced with the LMDZ4 atmo- spheric general circulation model to assess SMB variation in the 21st and the 22nd centuries under two different scenarios. The higher resolution of SMHiL reproduces the geographical patterns of SMB better and induces a significantly higher averaged SMB over the grounded ice-sheet for the end of the 20th century. Our comparison of more than 2700 quality-controlled field data showed that LMDZ4 and SMHiL fit the observed values equally well. Never- theless, field data below 2000 m a.s.l. are too scarce to settle SMHiL efficiency. Measuring the SMB in these undocumented areas is a future scientific priority. Our results suggest that running LMDZ4 at a finer resolution may give a future increase in SMB in Antarctica between 15% to 30% higher than its standard resolution. Future changes in the Antarctic SMB at low elevations will result from the conflict between higher snow accumulation and runoff. For this reason, developing a downscaling model was crucial to represent processes in sufficient detail and correctly model the SMB in coastal areas. [less ▲]

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See detailTesting palaeoclimate and palaeovegetation model reconstructions with palaeovegetation data : an application to the Middle Miocene
François, Louis ULg; Utescher, Torsten; Hamon, Noémie et al

Poster (2013, April)

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See detailÉtude de la virulence des sérotypes 4 et 9 du virus de la peste équine dans deux modèles murins
De la Grandière de Noronha Cotta, Maria Ana ULg; Zonta, William ULg; Dal Pozzo, Fabiana ULg et al

Poster (2013, April)

Objectifs Le virus de la peste équine (African horse sickness virus ; AHSV) est un virus segmenté à ARN double brin, appartenant à la famille des Reoviridae et au genre Orbivirus. L’AHSV se différencie en ... [more ▼]

Objectifs Le virus de la peste équine (African horse sickness virus ; AHSV) est un virus segmenté à ARN double brin, appartenant à la famille des Reoviridae et au genre Orbivirus. L’AHSV se différencie en 9 sérotypes distincts et est transmis par la piqûre d’un vecteur, principalement Culicoides imicola. L’AHSV cause une sévère morbidité et un taux de mortalité qui peut atteindre 95 % chez les chevaux avec de lourdes conséquences économiques. L’établissement d’un modèle d’étude en souris est nécessaire pour plusieurs applications, comme l’investigation de la pathogénie de ce virus, l’étude de la virulence, l’étude d’efficacité de nouveaux vaccins. Méthodes Deux modèles murins, soit une lignée de souris déficientes en récepteur à l’interféron α (A129 KO ou IFNAR -/-), et une lignée immunocompétente (A 129 WT) ont été testées. Les virus de sérotypes 4 et 9 de l’AHSV ont été utilisés pour les inoculations des souris ; ces deux sérotypes ont été à l’origine des épidémies observées en Espagne en 1969 et à la fin des années 80 en Espagne et au Portugal. Le virus a été inoculé par voie sous-cutanée (SC) et/ou par voie intra-nasale (IN) et un groupe de souris témoin (mock-infected) a été utilisé pour les deux modèles testés. Des échantillons de sang ont été prélevés de chaque souris infectée et témoin à intervalles réguliers. Les organes (foie, rate, reins, poumon et cerveau) ont été prélevés à la fin de l’expérience pour la plupart des souris ou lors de l’euthanasie des souris qui présentaient des signes cliniques très prononcés. Tous les échantillons, sang et organes, ont été analysés par qRT-PCR avec comme cible le segment 7 codant la protéine VP7 de l’AHSV qui est la protéine de structure la plus conservée entre les différents sérotypes. Résultats Les deux sérotypes de l’AHSV ont été détectés par qRT-PCR jusqu’à 3 semaines post-infection (ce qui correspond à la fin de l’expérience) dans le sang des souris IFNAR -/- et A129 WT infectées par la voie SC. Le virus de sérotype 4 atteint des niveaux de virémie légèrement plus élevés par rapport au virus de sérotype 9. Les souris A129 WT infectées par la voie intra-nasale ne montrent à aucun moment de l’expérience de virémie détectable par la qRT-PCR. Le pic de virémie a été mesuré entre le jour 2 et le jour 4 post-infection pour les deux lignées de souris. Au pic de virémie, la quantité de ADNc correspondant au segment-7 viral, après quantification par qRT-PCR, était plus élevée chez les souris IFNAR -/-. Conclusions Les souris immunodéficientes (IFNAR -/-) présentent des caractéristiques cliniques et biologiques permettant l’établissement d’un modèle in vivo pertinent. Selon les premiers résultats obtenus, il semble que la voie sous-cutanée soit la voie à privilégier pour les expériences in vivo futures. La mise au point de ce modèle sur souris permet de disposer d’un outil efficace et nécessaire pour l’étude in vivo de l’AHSV, afin de caractériser in vivo la virulence de ce virus et de suivre l’évolution des populations virales pendant la multiplication virale in vivo. Remerciements Recherche financée par le service Recherche Contractuelle, Service Public Fédérale, Santé Publique, Sécurité de la Chaîne alimentaire et Environnement (RT 12/6262 INDEVIREQ 2.0) [less ▲]

Detailed reference viewed: 32 (12 ULg)
See detailGlioblastoma metastases:case report and literature review
REUTER, Gilles ULg; Lombard, Arnaud ULg; SCHOLTES, Félix ULg et al

Poster (2013, March 30)

Detailed reference viewed: 33 (12 ULg)
Peer Reviewed
See detailPB15’s discrimination in oil paintings by non-destructive methods
Defeyt, Catherine ULg; Vandenabeele, Peter; Van Pevenage, Jolien et al

Poster (2013, March 29)

Detailed reference viewed: 12 (0 ULg)
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See detailEffects of climate change on the river Meuse: Hydraulic 2D modeling from Amspin to Maaseik (and beyond)
Huismans, Ymkje; Dewals, Benjamin ULg; van der Mark, Rolien et al

Poster (2013, March 22)

Detailed reference viewed: 19 (6 ULg)
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See detailLaser Cooling of Iron Atoms
Huet, Nicolas ULg; Krins, Stéphanie ULg; Bastin, Thierry ULg

Poster (2013, March 21)

We report on the first laser cooling of Iron atoms. Our laser cooling setup makes use of 2 UV laser radiations sent colinearly in a 0.8 m Zeeman slower. One laser is meant for optical pumping of the Iron ... [more ▼]

We report on the first laser cooling of Iron atoms. Our laser cooling setup makes use of 2 UV laser radiations sent colinearly in a 0.8 m Zeeman slower. One laser is meant for optical pumping of the Iron atoms from the ground state to the lowest energy metastable state. The second laser cools down the atoms using a quasi-perfect closed transition from the optically pumped metastable state. The velocity distribution at the exit of the Zeeman slower is obtained from a probe laser crossing the atomic beam at an angle of 50 degrees. The fluorescence light is detected using a photomultiplier tube coupled with a boxcar analyzer. The Iron atom beam is produced with a commercial effusion cell working at around 1600°C. Our laser radiations are stabilized using standard saturated-absorption signals in both an Iron hollow cathode absorption cell and an Iodine cell. [less ▲]

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See detailMultifractality of quantum wave functions
Martin, John ULg; Garcia-Mata, Ignacio; Giraud, Olivier et al

Poster (2013, March 19)

We study the multifractality of individual wave packets in a periodically kicked system through a combination of numerical and analytical works. We consider a version of the mathematical Ruijsenaars ... [more ▼]

We study the multifractality of individual wave packets in a periodically kicked system through a combination of numerical and analytical works. We consider a version of the mathematical Ruijsenaars-Schneider model and reinterpreted it physically in order to describe the spreading with time of quantum wave packets in a system where multifractality can be tuned by varying a parameter [1]. We compare different methods to measure the multifractality of wave packets and identify the best one. We find the multifractality to decrease with time until it reaches an asymptotic limit, which is different from the multifractality of eigenvectors but related to it, as is the rate of the decrease. Our results could guide the study of experimental situations where multifractality is present in quantum systems. [less ▲]

Detailed reference viewed: 23 (4 ULg)
See detailHighly non-classical symmetric states of an N-qubit system
Baguette, Dorian ULg; Martin, John ULg

Poster (2013, March 19)

Detailed reference viewed: 22 (8 ULg)
Peer Reviewed
See detailInhibition of Fusarium culmorum and Cochliobolus sativus growth
Kaddes, Amine ULg

Poster (2013, March 19)

Detailed reference viewed: 33 (9 ULg)
See detailWeakening of superradiance due to dipole-dipole interactions
Damanet, François ULg; Martin, John ULg

Poster (2013, March 19)

Detailed reference viewed: 26 (13 ULg)
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See detailSelf-Defining Memories and Identity in Schizophrenia: Preliminary Results.
Boulanger, Marie ULg; Marchal Laurie; Blairy, Sylvie ULg

Poster (2013, March 18)

The reciprocal relationship between autobiographical memory (AM) and identity is well known. In schizophrenia, there is evidence that both identity and AM are impaired. Indeed, identity has been described ... [more ▼]

The reciprocal relationship between autobiographical memory (AM) and identity is well known. In schizophrenia, there is evidence that both identity and AM are impaired. Indeed, identity has been described as fragmented, instable or still discontinuous in these patients (Boulanger et al., submitted; deBonis et al., 1995; Nieznanski, 2004). Further, schizophrenia patients’ (SCh) AM impairments were described as difficulties to retrieve specific memories (Cuervo-Lombard et al., 2007; D’argembeau et al., 2008; Neumann et al., 2007; Wood et al., 2006). SCh have specificity impairment for mill run autobiographical memories (AMs) and also, for AMs particularly important for construction and continuity to identity as self-defining memories (SDMs; Benounna-Greene, 2001; Raffard et al., 2009, 2010; Robinson and Taylor, 1998). SDMs have been particularly relevant in understanding the relationship between the identity and AM. Identity emerges during late adolescence and early adulthood period called “remimiscence bump period” because, it is characterized by a profusion of recalled memories in comparison to others periods of life span. Possibly, many memories from this period are of SDMs (Singer & Salovey, 1993) and have a powerful effect in binding the identity to a specific reality. Consequently, we supposed that identity impairments showed by SCch are related to SDMs deficits. 19 SCh and 19 healthy controls paired participated to this study. They were asked to give ten enduring “I am” statements that they felt “defined their identity.” Then, they selected the three statements among the ten, which are the “most personally significant to their sense of identity”. They were asked to recall three SDMs by each of three statements selected. Afterwards, they were asked to give: (1) their age for each statement when they felt it was a significant part of their identity, (2) their age at the time that the remembered event occurred. In parallel, the participants were completed neuropsychological measures, BDI-II, PANSS and, an identity stability measure. The results are discussed on the light of previous research [less ▲]

Detailed reference viewed: 54 (4 ULg)
See detailUse of supercritical carbon dioxide to elaborate drug-loaded polymeric implants
Champeau, Mathilde; Thomassin, Jean-Michel ULg; Jérôme, Christine ULg et al

Poster (2013, March 17)

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See detailPILOT PROJECT « WALPHY »: WALLOON EXPERIMENTATION OF RIVER RESTORATION
Peeters, Alexandre ULg; Verniers, Gisèle; de le Court, Bernard et al

Poster (2013, March 13)

Detailed reference viewed: 34 (3 ULg)
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See detailSearching for water in the atmosphere of the hot Saturn WASP-49b
Delrez, Laetitia ULg; Lendl, M.; Gillon, Michaël ULg et al

Poster (2013, March 11)

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 present here ... [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 present here some preliminary results of our VLT program that consisted in monitoring three transits of the new 'hot Saturn' WASP-49b (Lendl et al. 2012) with the FORS instrument in Multi-Object Spectroscopic mode (MXU). [less ▲]

Detailed reference viewed: 14 (0 ULg)
See detailPrecisely controlled mesoporous films to assess the role of architecture in nanocrystal-.based electrodes for Li-ion batteries
Krins, Natacha ULg; Buonsanti, Raffaella; Shukla, Alpesh K. et al

Poster (2013, March 04)

Detailed reference viewed: 12 (1 ULg)
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See detailThiamine and thiazolium binding proteome includes DJ-1, amyloid beta and several membrane proteins
Bunik; Parkhomenko, Y; Kaehne, T et al

Poster (2013, March)

Detailed reference viewed: 34 (3 ULg)
Peer Reviewed
See detailPhotocatalytic TiO2 Macroscopic Fibers Obtained Through Integrative Chemistry
Kinadjian, Natacha ULg; Le Bechec, Mickael; Pigot, Thierry et al

Poster (2013, March)

The photocatalytic properties of titanium dioxide depend not only on its electronic properties, but also on the material size and shape, which can increase interactions between the reactants and catalyst ... [more ▼]

The photocatalytic properties of titanium dioxide depend not only on its electronic properties, but also on the material size and shape, which can increase interactions between the reactants and catalyst. Most studies to date show that reducing the particle size down to the nanoscale increases photocatalytic efficiency, as a result of a higher surface to volume ratio and because a larger proportion of the material is actually irradiated by light. We demonstrate that a multiscale shape design, which integrates surface roughness, particle shape, and 1D material processing and orientation, can favor photocatalytic properties in the solidgas regime, especially mineralization (conversion into CO2), when the hierarchical 1D orientation of the material is combined with unidirectional gas flow. Several materials with hierarchical structure were prepared and characterized. They have been tested for the photocatalytic mineralization of gaseous acetone and compared with commercial catalysts. Our study reveals that a suitable combination of multiscale design and optimization of the material orientation and gas flow favors high mineralization. [less ▲]

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See detailLong term stability of TiO2 templated multilayer films used as high efficiency photoelectrode in liquid DSSCs
Dewalque, Jennifer ULg; Nguyen, Ngoc Duy ULg; Henrist, Catherine ULg et al

Poster (2013, March)

To our knowledge, the stability results reported in the literature only concern cells made from classical doctor-bladed or screen-printed nanoparticles films. This study focuses on the comparison of the ... [more ▼]

To our knowledge, the stability results reported in the literature only concern cells made from classical doctor-bladed or screen-printed nanoparticles films. This study focuses on the comparison of the long-term stability of these cells with DSSCs working with templated mesoporous films. Indeed, the increased surface area of templated films could lead to a faster degradation of the resulting cells. In accordance with IEC:1646:1996 standard tests, light soaking test at 45°C has been applied to determine the cells stability under prolonged illumination. Moreover, thermal stress in the dark has been applied. Unfortunately, due to the sealing material heat resistance, thermal stress test was only performed at 45°C. [less ▲]

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See detailTools for surveillance system evaluation: Reviewing the need for participatory approaches
Calba, Clémentine; Grobois, Vladimir; Peyre, Marisa et al

Poster (2013, March)

While the need for effective animal health surveillance is widely recognised for diseases management, most veterinary services are facing significant budget constraints. There is a real need to develop ... [more ▼]

While the need for effective animal health surveillance is widely recognised for diseases management, most veterinary services are facing significant budget constraints. There is a real need to develop cost-effective surveillance systems. To ensure quality of these systems, there is a further need to design comprehensive, timely, effective and affordable evaluation frameworks. Depending on epidemiological, sociological and economic factors, animal diseases surveillance systems can be complex, likewise the choice of attributes to describe them and therefore the choice of methods and tools to evaluate them. Participatory approaches could provide the framework needed to tackle that complexity with sufficient flexibility. [less ▲]

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See detailRelevance of pedotopographical indicators in the assessment of spatial distributions of soil depth and soil water resources under forest stands : General Methodology
Ridremont, François ULg; Deraedt, Deborah ULg; Robert, Tanguy et al

Poster (2013, March)

Water resources constitute one of the most decisive factors of the adaptation of forest ecosystems facing climate changes. The assessment of soil water resources should lead a better understanding of ... [more ▼]

Water resources constitute one of the most decisive factors of the adaptation of forest ecosystems facing climate changes. The assessment of soil water resources should lead a better understanding of forest sites vulnerability to water stress and provide appropriate management recommendations for the choice of trees species and sylvicutlural techniques. This study aims to assess the relevance of pedotopographical indicators in the assessment of spatial distributions of soil depth and soil water resources under forest stands. The study area is located in the shale-slate stones pedological context of the Belgian Ardenne ecoregion. It falls within the constrasted relief of the Houille watershed and is 90% covered by forests. The estimation of spatial and profile distributions of water resources will be based on a multi-year monitoring of real time soil moisture content using TDR technology : subsurface (15 cm) on systematic sampling and profile (. 70 cm) on 32 local sites equipped with TDR pvc tubes. Additional laboratory analysis will be conducted to determine soil properties influencing soil water content (texture, organic matter content...). Directly impacting soil water content, soil depth and stoniness will be investigated in contrasting topographic conditions by (i) two traditional and destructive methods : 32 soil pits & 160 holes with auger soil; and (ii) an electromagnetic and non intrusive method : 5120m of Ground Penetrating Radar traces with 200 and 500 MHz antennas. The identification of soil and terrain attributes, able to explain distribution of soil water content and soil depth, will be done by digital cartographic resources exploitation : (i) Digital Elevation Model with different spatial resolutions (Lidar, 1 m2; Erruissol DEM, 100 m2; Aster DEM, 9.103m2) and (ii) Digital Soil Map of Wallonia. It is expected that the results could lead to the development of operational tools to ensure the forest site . tree species adequacy in order to increase resilience of forest ecosystems to ecological drifts. [less ▲]

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See detailThe Day George Avellis Met Miller Fisher – About the Unsual Presentation of an Anti-GQ1b IgG Antibody Syndrome
PHAN BA, Remy ULg; Parmentier, Eric ULg; LIEVENS, Isabelle ULg et al

Poster (2013, March)

Objective: OBJECTIVE: To describe the clinical, laboratory and electrophysiological features of a patient who presented an Avellis syndrome as the initial feature of Miller Fisher syndrome (MFS ... [more ▼]

Objective: OBJECTIVE: To describe the clinical, laboratory and electrophysiological features of a patient who presented an Avellis syndrome as the initial feature of Miller Fisher syndrome (MFS). Background: BACKGROUND: Anti-GQ1b Ig antibodies are associated with an increasing spectrum of neurological disorders, including MFS and Guillain-Barre syndrome (GBS). Design/Methods: DESIGN/METHODS: Clinical case description. Results: RESULTS: A 67-year old woman was seen for subacute dysphagia and dysphonia, preceded by rapidly worsening paresthesia of the extremities and face, with a history of upper respiratory tract infection two weeks before admission. Nasotracheal examination showed a left velopalatine and left vocal cord paresis. Twelve hours later, sensory ataxia appeared and deep tendon reflexes weakened. Diffuse paresis affecting predominantly the axial muscles developped. Oculomotricity was preserved. Brain MRI was normal, while EMG suggested a mild sensory neuropathy. Within hours, dysphagia worsened and dyspnea appeared, prompting ICU admission for airway support. She developed a proximal paresis and dysautonomia, global areflexia. CSF findings were unremarkable. IVIg were administered at a dose of 0.2g/kg per day during five days. Control EMG showed signs of polyradiculoneuropathy. She gradually recovered and was discharged at home after 32 days, with only a slight velopalatal paresis and a mild fatigue. Anti-ganglioside antibodies screen was positive for IgG-GM3, GD1b, GD3, GQ1b, GT1a and GT1b. In front of this clinical and biological picture, the diagnosis of atypical MFS was retained. Thirty day after discharge, both clinical and electrophysiological parameters were normalised. Conclusions: CONCLUSIONS: This case highlights that (i) MFS can show atypical presentation (here a pure Avellis syndrome, never reported in the context of the anti-GQ1b syndrome to our knowledge) and should be considered in front of an isolated impaired cranial nerve function, even in the absence of the classical triad of ophtalmoplegia, areflexia and ataxia, and (ii) that the boundaries between MFS and GBS are usually neater in textbooks than in real life. [less ▲]

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See detailHierarchical Porous TiO2 thin films by soft and dual templating: A quantitative approach of specific surface and porosity
Henrist, Catherine ULg; Cloots, Rudi ULg; Colson, Pierre ULg et al

Poster (2013, March)

Hierarchical porous structures, with different pore sizes, constitute an important field of research for many applications. However, increasing the pore size results in the decrease of specific surface ... [more ▼]

Hierarchical porous structures, with different pore sizes, constitute an important field of research for many applications. However, increasing the pore size results in the decrease of specific surface. There is a need to quantify and predict the resulting porosity and specific surface. We have prepared hierarchical porous TiO2 thin films either by surfactant templating (soft) or dual surfactant/microspheres templating (soft/hard). They all show narrow, bimodal distribution of pores. Soft templating route leads to very thin films showing high specific surface and bimodal porosity with diameters of 10 nm and 54 nm. Dual templating route combines a Pluronic surfactant-based precursor solution with polystyrene (PS) microspheres (diam. 250 nm) in a one-pot simple process. This gives thicker films with a bimodal distribution of pores (8 nm and 165-200 nm). The dye loading of hierarchical films is compared to pure Pluronic-templated TiO2 films and shows a relative decrease of 29% for Single Templating (ST) and 43% for Dual Templating (DT-250). Finally, a geometrical model is proposed and validated for each system, based on the agreement between calculated specific surfaces and experimental dye loading with N719 dye. [less ▲]

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See detailLes représentations d’attachement chez les enfants de 5 à 8 ans placés en institution
Degraux, Christine ULg; Deschênes, Marie; Cyr, Chantal et al

Poster (2013, March)

A ce jour aucune étude n’a investigué la qualité d’attachement d’enfants hébergés en institution suite à de la maltraitance ou des négligences sévères. Or les recherches menées auprès de populations ... [more ▼]

A ce jour aucune étude n’a investigué la qualité d’attachement d’enfants hébergés en institution suite à de la maltraitance ou des négligences sévères. Or les recherches menées auprès de populations maltraitées indiquent de graves conséquences sur leur patron d’attachement ((Cyr et al., 2010) et de plus en plus de recherches soulignent les effets d’un attachement insécurisé sur le développement, surtout s’il est de type désorganisé (Lyons-Ruth & Jacobvitz, 2008). C’est pourtant ce type d’attachement qui est observé auprès d’environ la moitié des adolescents hébergés ou des adultes ayant été hébergés (Nowacki & Schoelmerich, 2010; Wallis & Steele, 2001; Webster et al., 2009). Cette étude a pour objectif d’évaluer la prévalence des modes d’attachement dans un échantillon d’enfants hébergés âgés entre 5 et 8 ans (N=73). L’évaluation de l’attachement a porté non pas sur les comportements d’attachement mais sur les modèles relationnels que les enfants ont intériorisés suite aux expériences vécues auprès de leur(s) figure(s) d’attachement. La procédure des histoires à compléter a été utilisée, filmée et codée en Q-sort via les cartes pour le complément d’histoires (C.C.H.) développé par Miljkovitch et collaborateurs (2003). Les résultats indiquent que 22% des enfants présentent un attachement de type sécure, 37% de désorganisé, 31% d’évitant et 10% d’ambivalent. Ceux-ci soulignent qu’à cet âge aussi, la désorganisation est observée dans de nombreux cas et nous constatons également qu’un nombre élevé d’enfants présentent des stratégies d’évitement qui risquent de leur causer de nombreuses difficultés relationnelles. Etant donné l’importance d’une prise en charge précoce des troubles d’attachement, il est primordial de s’interroger sur les interventions à proposer dans un cadre institutionnel face aux besoins spécifiques de ces enfants. [less ▲]

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See detailEverolimus Plus Exemestane Versus Everolimus or Capecitabine Monotherapy in Breast Cancer : BOLERO-6
Ejlertsen, Bent; JERUSALEM, Guy ULg; Hurvitz, Sara et al

Poster (2013, March)

The data from this trial will provide insight into the safety and efficacy of the combination of EVE and EXE versus EVE or capecitabine monotherapy in women with ER+, HER2- ABC progressing on/after prior ... [more ▼]

The data from this trial will provide insight into the safety and efficacy of the combination of EVE and EXE versus EVE or capecitabine monotherapy in women with ER+, HER2- ABC progressing on/after prior LET or ANA. [less ▲]

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See detailCharacterization of monoclonal antibodies against Hemolysin Alpha of Staphylococcus aureus
Crasson, Oscar ULg; Rhazi, Noureddine; Kinet, Marie et al

Poster (2013, February 26)

In this study, vaccine-based targeting of Hemolysin Alpha (HLA) provides protection against lethal staphylococcal infection in a murine model system, suggesting that a monoclonal antibody-based therapy ... [more ▼]

In this study, vaccine-based targeting of Hemolysin Alpha (HLA) provides protection against lethal staphylococcal infection in a murine model system, suggesting that a monoclonal antibody-based therapy may likewise prove to be efficacious for prevention and treatment of this infection. We report the generation of four distinct anti-α-hemolysin monoclonal antibodies (MAbs) that antagonize toxin activity in vitro and protecting experimental animals against lethal S. aureus infection. [less ▲]

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See detailSAHBEN, an accessible surface-based elastic network to insert a protein in a complex lipid membrane
Dony, Nicolas ULg; Crowet, Jean-Marc ULg; Joris, Bernard ULg et al

Poster (2013, February 26)

Study of membrane proteins have become one of the most challenging fields in biology. Solving their structure is one important step toward the understanding of their physiological activity but despite the ... [more ▼]

Study of membrane proteins have become one of the most challenging fields in biology. Solving their structure is one important step toward the understanding of their physiological activity but despite the recent advances in membrane protein crystallization, it represents less than 1 % of the entries in the Protein Data Bank. Therefore, calculation methods to study membrane proteins are helpful to complement experimental studies and fill the gap between the information obtained from the sequence and/or structure, the experimental results and the biological activity. Molecular Dynamics (MD) is a method of choice for membrane simulations and the rising of coarse-grained forcefields has opened the way to longer simulations with reduced calculations times. However, these approaches have two main drawbacks, the preparation of the membrane system and the preservation of the 3D protein structure, which is not trivial in CG approach. To circumvent these problems, we propose to use a modified version of the Gromacs tool genbox to easily insert lipids and a network based on hydrogen bonds and accessible surface to maintain the protein 3D structure. This protocol is available through a website (gcgs.gembloux.ulg.ac.be). [less ▲]

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See detailBiochemical and Structural studies of the type I tagatose bisphosphate aldolases
Freichels, Régine ULg; Guarino, Carla; Delmarcelle, Michaël ULg et al

Poster (2013, February 26)

Detailed reference viewed: 64 (18 ULg)
See detailPrediction of membrane protein structures and TM interactions Rosetta and molecular dynamic studies
Crowet, Jean-Marc ULg; Dony, Nicolas ULg; Joris, Bernard ULg et al

Poster (2013, February 26)

The structures of membrane domains of the Divisome proteins and BlaR are not known and there is no homolog proteins of known structure to build homolgy models. Although the structure prediction of ... [more ▼]

The structures of membrane domains of the Divisome proteins and BlaR are not known and there is no homolog proteins of known structure to build homolgy models. Although the structure prediction of membrane proteins seems easier than for globular proteins, their ab initio prediction remains a difficult task. Only few methods have been used and validated on experimental pdb structures. By using the MARTINI or Bond coarse grain representation, the multimerization of transmembrane helices has been carried out by molecular dynamics, and the structure of several membrane proteins has been predicted by a tool of the Rosetta package. These methods are used here to predict the structure of the membrane embedded part of the politopic proteins from the divisome (FtsW, FtsK, FtsX and MraY) and BlaR. In a following part the MARTINI force field can be used to predict the TM helices interactions between the Divisome protein members. [less ▲]

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

Poster (2013, February 26)

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See detailTreasures from the cave – mining for actinomycetes diversity
Maciejewska, Marta ULg

Poster (2013, February 26)

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See detailIn silico study of antimicrobial cyclic peptides Sequence analysis, molecular modelling and multi-scale molecular dynamics
Crowet, Jean-Marc ULg; Soumillion, Patrice; Brasseur, Robert ULg et al

Poster (2013, February 26)

The selection and use of antimicrobial cyclic peptides is an active way of research. These peptides are naturally produced by several microorganisms et libraries of biosynthetic peptides are actually ... [more ▼]

The selection and use of antimicrobial cyclic peptides is an active way of research. These peptides are naturally produced by several microorganisms et libraries of biosynthetic peptides are actually build to find new antibiotics candidats. However, the mecanism of action of these peptides is not well known and it exists several hypothesis for their interactions with membrane. These peptides are causing broad perturbations to lipidic membranes and it has been shown that they can form disordered toroidal pores or self assemble as amphipathic nanotubes leading to lipid extrusion. Through the analysis of several peptides from the libraries of Pr Soumillion with increasing activity it will be possible to study the relation between the sequence/structure and the membrane activity of these peptides. This will help to decipher between preferential modes of action and the parameters important for the activity. [less ▲]

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See detailAn occupational therapist as a new professional at home: which profiles of clients are reached ?
Maggi, Patrick ULg; de Almeida Mello, Johanna; Delye, Samuel ULg et al

Poster (2013, February 22)

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See detailCase management projects enabling frail older people to stay in their own home a nested analysis within the framework of the evaluation of Protocol 3 projects
Van Durme, Thérèse; Macq, Jean; Lopez Hartmann, Maja et al

Poster (2013, February 22)

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See detailCHARACTERIZATION OF AGRICULTURAL SPRAY BY DIGITAL ANALYSIS OF SHADOWGRAPHY IMAGES
De Cock, Nicolas; Massinon, Mathieu ULg; Lebeau, Frédéric ULg

Poster (2013, February 08)

Agricultural sprays are among the most common two-phase flows studied because their characteristics determine the efficiency of treatment as well as environmental contamination. At present, the relevance ... [more ▼]

Agricultural sprays are among the most common two-phase flows studied because their characteristics determine the efficiency of treatment as well as environmental contamination. At present, the relevance of different characterization techniques of the highly polydispersed sprays used in this application remains controversial. Digital analysis of shadowgraphy images presents an attractive option for the characterization of both velocity and size of droplets present in the spray. This study presents an overview of the contrast problems inherent in the use of backlighted images and propose appropriate solution to ensure the quality of measurements. Generally, background light presents heterogeneities associated with light sources and optical arrangement. These can be solved by substracting from each images a composite background. An other particular focus is given to one major drawback of volumetric lighting, the presence of out focus droplets. These droplets have to be removed during the image analysis process because the measurement of their diameters can't be done accuratly. The rejection of these out of focus objects is based on a quantitative parameter which was calibrated with a obliquely shot monodispersed spray. The final step of the image processing is determining velocity of the droplet by tracking a same droplet on two successive images. The tracking algorithm is based on the size of the droplet, its more probable displacement and its direction. [less ▲]

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See detailIs ultra-short cold ischemia the key to IBDL avoidance in DCD-LT?
DETRY, Olivier ULg; DE ROOVER, Arnaud ULg; Ledinh, Hieu et al

Poster (2013, February 08)

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See detailInfluence of rhizobacterial volatile compounds on growth and root system architecture of Brachypodium distachyon (L.) Beauv.
Mendaluk, Magdalena ULg; Varin, Sébastien; Baudson, Caroline ULg et al

Poster (2013, February 08)

Many rhizobacterial strains are classified as plant growth-promoting rhizobacteria (PGPR) and are potentially useful to enhance plant fitness and productivity. Among the mechanisms by which PGPR improve ... [more ▼]

Many rhizobacterial strains are classified as plant growth-promoting rhizobacteria (PGPR) and are potentially useful to enhance plant fitness and productivity. Among the mechanisms by which PGPR improve plant growth, the emission of volatile organic compounds (VOCs) and their biological impacts on plants remain little documented. The aim of this work is to evaluate the growth promotion ability of 19 bacterial strains on the model grass Brachypodium distachyon Bd21 (Bd21), with a focus on this peculiar mode of interaction. A collection of 19 strains was selected for their known growth promotion potential. The impact of the rhizobacteria on the model grass was studied using an in vitro cocultivation system allowing interactions through VOCs without physical contact between plants and bacteria. The results show that the VOCs of several strains promote total biomass production, modulate biomass partitioning and affect shoot and root architecture of Bd21. The effects of the PGPR strains emitting different volatile blends were investigated via principal component analysis coupled to clustering and univariate analysis to unravel their biological effects. On the basis of volatile emissions and of their effects on plant growth, two strains have been selected in order to evaluate such interactions using an ex vitro system. The set-up of this system is in progress. [less ▲]

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