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See detailTrophic plasticity of Antarctic echinoids under contrasted environmental conditions
Michel, Loïc ULg; David, Bruno; Dubois, Philippe et al

Poster (2016, February 12)

Echinoids are common members of Antarctic zoobenthos, and different groups can show important trophic diversity. As part of the ANT-XXIX/3 cruise of RV Polarstern, trophic plasticity of sea urchins was ... [more ▼]

Echinoids are common members of Antarctic zoobenthos, and different groups can show important trophic diversity. As part of the ANT-XXIX/3 cruise of RV Polarstern, trophic plasticity of sea urchins was studied in three neighbouring regions (Drake Passage, Bransfield Strait and Weddell Sea) featuring several depth-related habitats offering different trophic environments to benthic consumers. Three families with contrasting feeding habits (Cidaridae, Echinidae and Schizasteridae) were studied. Gut content examination and stable isotopes ratios of C and N suggest that each of the studied families showed a different response to variation in environmental and food conditions. Schizasteridae trophic plasticity was low, and these sea urchins were bulk sediment feeders relying on sediment-associated organic matter in all regions and/or depth-related habitats. Cidaridae consumed the most animal-derived material. Their diet varied according to the considered area, as sea urchins from Bransfield Strait relied mostly on living and/or dead animal material, while specimens from Weddell Sea fed on a mixture of dead animal material and other detritus. Echinidae also showed important trophic plasticity. They fed on various detrital items in Bransfield Strait, and selectivity of ingested material varied across depth-related habitats. In Weddell Sea, stable isotopes revealed that they mostly relied on highly 13C-enriched food items, presumably microbially-reworked benthic detritus. The differences in adaptive strategies could lead to family-specific responses of Antarctic echinoids to environmental and food-related changes. [less ▲]

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See detailMercury and persistent organic pollutant concentrations in free-ranging bottlenose dolphins from Lower Keys and Coastal Everglades (South Florida)
Damseaux, France ULg; Kiszka, Jeremy; Heithaus, Michael et al

Poster (2016, February 12)

The bottlenose dolphin (Tursiops truncatus) is a major apex predator and the most common cetacean species found in nearshore waters of South Florida, including the Lower Florida Keys (LFK) and the Florida ... [more ▼]

The bottlenose dolphin (Tursiops truncatus) is a major apex predator and the most common cetacean species found in nearshore waters of South Florida, including the Lower Florida Keys (LFK) and the Florida Coastal Everglades (FCE). The objective of this study was 1) to assess contamination levels of total mercury (T-Hg) in skin and persistent organic pollutants (PCBs, PBDEs, DDT, HCH, HCB, DLCs and PCDD/Fs) in blubber samples of bottlenose dolphins from the LFK (8 males and 16 females) and from the FCE (13 males and 9 females). Pollutants were analysed by the mean of Direct Mercury analyser (for T-Hg), GC-ECD (POPs) and GC-MS (DLCs and PCDD/Fs). The PCBs were the main compounds found in bottlenose dolphins from the LFK and FCE. The most present congeners where the CB no. 28, 52, 101, 138, 153 and 180 (ΣPCBs LFK males: 13420.5 ng.g-1 lipids, ΣPCBs LFK females: 9683.4 ng.g-1 lipids, ΣPCBs FCE males: 5637.9 ng.g-1 lipids, ΣPCBs FCE females: 1426.9 ng.g-1 lipids). PCBs concentrations were significantly higher in individuals from the LFK than those from the FCE but significantly lower than those from other locations in the south-eastern US. Unlike organic pollutants, T-Hg concentrations were significantly higher in FCE male dolphins (LFK: 2936.0 ng.g-1 dw, FCE: 10048.3 ng.g-1 dw). These high concentrations were the highest recorded in the south-eastern US and are most likely due to the presence of mangrove ecosystems. This study highlights the complexity of contaminant dynamics (inorganic vs. organic), even at small spatial scales. [less ▲]

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See detailNitrous oxide dynamics in sea ice
Kotovitch, Marie ULg; Fripiat, François; Moreau, Sebastien et al

Poster (2016, February 12)

Fluctuations in greenhouse gases (GHGs) concentration alter the energetic budget of the climate system. There is high confidence that natural systems related to snow, ice and frozen ground (including ... [more ▼]

Fluctuations in greenhouse gases (GHGs) concentration alter the energetic budget of the climate system. There is high confidence that natural systems related to snow, ice and frozen ground (including permafrost) are affected. Nitrous oxide (N2O) is one of the potent GHG naturally present in the atmosphere, but witch has seen his concentration growing since industrial era. N2O has a lifetime in the atmosphere of 114 years and a global warming potential (GWP) of 298 to be compared to carbon dioxide that has a GWP of 1. N2O is also describe as the dominant ozone-depleting substance emitted in the 21st Century. Yet, there are still large uncertainties and gaps in the understanding of the cycle of this compound through the ocean and particularly in sea ice. Sources and sinks of N2O are therefore still poorly quantified. The main processes (with the exception of transport processes) involved in the N2O cycle within the aquatic environment are nitrification and denitrification. To date, only one study by Randall et al. present N2O measurements in sea ice. Randall et al. pointed out that sea ice formation and melt has the potential to generate sea-air or air-sea fluxes of N2O, respectively. Study on ammonium oxidation and anaerobic bacterial cultures shows that N2O production can potentially occur in sea ice. Denitrification can act as a sink or a source of N2O. In strictly anaerobic conditions, N2O is removed by denitrification. However, denitrification can also occur in presence of O2 at trace level concentrations (<0.2 mg L-1), and in these conditions there is a large N2O production. Recent observations of significant nitrification in Antarctic sea ice shed a new light on nitrogen cycle within sea ice. It has been suggested that nitrification supplies up to 70% of nitrate assimilated within Antarctic spring sea ice. Corollary, production of N2O, a by-product of nitrification, can potentially be significant. This was recently confirmed in Antarctic land fast ice in McMurdo Sound, where N2O release to the atmosphere was estimated to 4 µmol.m-2.yr-1. This assessment is probably an underestimate since it only accounts for dissolved N2O while a significant amount of N2O is likely to occur in the gaseous form like N2, O2 and Ar. Finally, nitrification produces little N2O in oxygenated waters but the N2O production yield from nitrification strongly increases as O2 levels decrease. Hence, it is not possible to distinguish the sources of N2O solely based on bulk N2O concentrations or environmental conditions, while deepened knowledge of processes is needed to well understand N2O emissions. [less ▲]

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See detailAnnual dynamics of pCO2 within bulk sea ice and related CO2 fluxes at Cape Evans (Antarctica)
Van Der Linden, Fanny ULg; Champenois, Willy ULg; Heinesch, Bernard ULg et al

Poster (2016, February 12)

Sea ice is a biome actively participating in the regional cycling of CO2 as both a source and a sink at different times of the year. In the frame of the YROSIAE project (Year-Round Ocean-Sea-Ice ... [more ▼]

Sea ice is a biome actively participating in the regional cycling of CO2 as both a source and a sink at different times of the year. In the frame of the YROSIAE project (Year-Round Ocean-Sea-Ice-Atmosphere Exchanges), annual dynamics of sea ice pCO2 was compared with CO2 fluxes measured by automated accumulation chambers at Cape Evans (Ross Island, Antarctica). Results confirmed a general trend of brine pCO2 supersaturation with respect to the atmosphere during the late winter (concentration of dissolved inorganic carbon - DIC - in brine and brine expulsion in the brine skim) leading to CO2 degassing, and undersaturation during the spring (carbon-uptake by autotrophs and brine dilution) leading to atmospheric CO2 uptake. Despite high primary production at the bottom of the ice in spring, DIC profiles suggest that sea ice as a whole appears to be net heterotrophic. Still, sea ice absorbs CO2 from the atmosphere, as a result of physical processes. Some variability in the CO2 fluxes (both in magnitude and sign) could not be explained by variability in sea ice pCO2 but rather seemed driven by variability in atmospheric conditions and sea ice surface properties. For instance, in late spring, CO2 fluxes showed a diurnal variability (from CO2 degassing to uptake) related to atmospheric temperature variations. Large and episodic CO2 fluxes were systematically positively correlated with strong wind events, and large CO2 degassing was observed over thin, wet and salty snow cover. [less ▲]

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See detailNew ventures in nuclear emergency planning and response: a governance perspective
Van Oudheusden, Michiel ULg; Rossignol, Nicolas ULg; Turcanu, Catrinel

Poster (2016, February 11)

Emergency and disaster management is structured by the complex interaction of natural, social, and technological factors, and contingent on features of culture and organization. Our research serves to ... [more ▼]

Emergency and disaster management is structured by the complex interaction of natural, social, and technological factors, and contingent on features of culture and organization. Our research serves to highlight how these features come into play and shape emergency planning, anticipation, and response. Based on qualitative and quantitative analyses, we devise more resilient, responsive, and adaptive emergency policies for implicated stakeholders (e.g. policymakers, emergency services, regulators) and society at large. Our research foci include citizen science initiatives and stakeholder forums on contaminated goods in the wake of the 2011 Fukushima accident. Our methods are grounded in vulnerability analysis, which accepts that vulnerability is an inherent trait of contemporary societies. [less ▲]

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See detailScience, technology and society: opening pathways for integrating social sciences and humanities into nuclear research
Turcanu, Catrinel; Meskens, Gaston; Perko, Tanja et al

Poster (2016, February 11)

The PISA programme was initiated in 1999 within the Belgian Nuclear Research Centre SCK•CEN to study the societal, political, cultural and ethical aspects of the development and use of nuclear technology ... [more ▼]

The PISA programme was initiated in 1999 within the Belgian Nuclear Research Centre SCK•CEN to study the societal, political, cultural and ethical aspects of the development and use of nuclear technology and applications of ionising radiation. The programme was launched as the result of an internal reflection acknowledging that insights from social sciences and humanities were required to better explore normative concepts such as precaution and sustainable development, and to understand attitudes towards nuclear technologies and its governance. This presentation elaborates on the objectives of PISA and its main research tracks. It shows that through its multi-disciplinary approach, the PISA programme of the Belgian Nuclear Research Centre SCK•CEN opens pathways towards such integration, and thus contributes to rendering nuclear research more reflective and more responsive towards society. It explicates the interactions between science, technology and society, in general, and the complexity of nuclear technology assessment, in particular. Last, but not least, due do its reflexive character, PISA research creates an epistemologically and socially enriching dynamic in the organisation itself. [less ▲]

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See detailVolatile Organic Compounds:a new tool to control barley pathogens?
Kaddes, Amine ULg; Massart, Sébastien ULg; Fauconnier, Marie-Laure ULg et al

Poster (2016, February 05)

Barley is threatened by various edaphic fungal diseases. In particular, common root rot caused by Fusarium culmorum and Cochliobolus sativus is causing between 9 and 23 % of yield losses. Today, since ... [more ▼]

Barley is threatened by various edaphic fungal diseases. In particular, common root rot caused by Fusarium culmorum and Cochliobolus sativus is causing between 9 and 23 % of yield losses. Today, since most of the chemicals used for crop protection are being forbidden, there is a growing need of sustainable ways to control these diseases. A recent study has shown that barley roots infected by common root rot emitted 23 Volatile Organic Compounds (VOCs) that were not emitted by healthy barley roots. In addition it was shown that the blend of these molecules negatively impacted the growth of the two fungi. The main objective of the present study was to determine which VOCs of the blend were the most efficient in this growth reduction, and to understand their mode of action. We have found that methyl propionate (MP) and methyl acrylate (MA) reduced significantly the development of the two fungi in vitro. We also observed an inhibition of the spores’ germination in the presence of the two esters. The effect of the two molecules on infected barley seeds was also tested. We have observed that the plants coming from the seeds in contact with the VOCs did not develop symptoms of the disease. The antifungal and antibacterial activity of these VOCs on a wider range of fungal and bacterial diseases was also tested in vitro with success The two esters that we have studied could thus be an interesting starting point in the development of a sustainable way to control barley’s diseases. [less ▲]

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See detailIn vitro evaluation of protein precipitation capacity of temperate browse species
Vandermeulen, Sophie ULg; Leblois, Julie ULg; Ramírez-Restrepo, Carlos Alberto et al

Poster (2016, February 05)

European agri-environmental policies are promoting the establishment of shrubs and trees on grasslands. The use of browse as fodder requires knowledge on their nutritive value since intensive production ... [more ▼]

European agri-environmental policies are promoting the establishment of shrubs and trees on grasslands. The use of browse as fodder requires knowledge on their nutritive value since intensive production systems are still relying on expensive and environment-costing protein sources. However, information on the influence of temperate condensed tannins (CT)-containing browse forage on rumen protein metabolism is elusive. The study aimed to assess the protein precipitation capacity (PPC) of 10 temperate browse species and establish the correlation between PPC values and plants CT content. PPC of foliage of 3 individuals per woody plants was measured using 2 model proteins: bovine serum albumin (BSA) and casein. The N content in protein solutions (4.6g/L; pH=6.8) was determined before and after adding each forage sample. Extractable CT concentration was quantified by spectrophotometry. The PPC varied across plant species (P<0.001). Corylus avellana had the highest ability to precipitate casein (52.4%). In contrast, the BSA precipitation (18.3%) of this plant was similar to Cornus sanguinea (12.7%), Quercus robur (12.1%) and Crataegus monogyna (11.0%). CT content ranged from 1.4 in Fraxinus excelsior to 82.7g/kg of depigmented sample in Corylus avellana (P<0.001) and was correlated to BSA (r=0.70; P<0.001) and casein PC (r=0.51; P<0.01). It was concluded that woody species could play a significant role in modifying protein metabolism, but further in vivo trials are required. [less ▲]

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See detailA glance on characterization of almond kernels from five varieties cultivated in eastern Morocco
Houmy, Nadia; Abid, M.; Addi, M. et al

Poster (2016, February 05)

The Green Morocco Plan is established for 2008-2020 to improve productivity in the agriculture sector and to plant more productive perennial tree crops such as almonds that are better suited for Morocco's ... [more ▼]

The Green Morocco Plan is established for 2008-2020 to improve productivity in the agriculture sector and to plant more productive perennial tree crops such as almonds that are better suited for Morocco's climate. Belgian Development Agency support almond orchards extension in eastern Morocco in purpose to achieve socio-economic improvement. This research is part of a local project (PROFAO) for development of almond in eastern Morocco. The present study evaluates some almond oil parameters fiber and protein content of five almond varieties (Beldi, Fournat, Ferraduel/Ferragnes and Marcona). The aim is to classify varieties on the basis of kernels content of oil and their richness of fibers. Significant variations were found among the five almond varieties examined. Almond oil content ranged from 48 % for Fournat to aproximativly 60 % for Marcona & Beldi. Fatty acids (FA) profiles are slightly different. Oleic acid ranged from 58 % for Marcona to 68 % for Beldi; linoleic acid ranged from 20 % for Beldi to 30 % for Marcona. Saturated FA (palmitic and stearic) were found at levels lesser than 10 %. In almond press cake, total protein content varied between 55 % for Beldi and 48 % for Fournat. The highest total fiber content was found for Fournat (25 %), however Beldi present the lowest rate (16 %). We conclude that Marcona & Beldi would be interesting varieties for almond oil; Fournat seems to be interesting for its richness in fiber. [less ▲]

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See detailRecent and rapid radiation of the lichen genus Sticta in the Western Indian Ocean islands
Simon, Antoine ULg; Magain, Nicolas ULg; Goffinet, Bernard et al

Poster (2016, February 05)

In the framework of a global project on the phylogeny of the lichen genus Sticta (Lobariaceae), extensive sampling was performed on the islands of Reunion and Mauritius as well as in several parts of ... [more ▼]

In the framework of a global project on the phylogeny of the lichen genus Sticta (Lobariaceae), extensive sampling was performed on the islands of Reunion and Mauritius as well as in several parts of Madagascar (mainly in two National Parks : Marojejy and Amber Mountain). The aim of this study is to provide the first comprehensive molecular phylogeny of the genus in the Western Indian Ocean islands (and more specifically of a presumably local endemic lineage), and to date its local radiation. DNA sequences were obtained from 69 specimens for four loci and phylogenetic relationships were inferred using maximum likelihood and Bayesian inferences methods. We estimated divergence times using BEAST. Thirty putative species can be recognized, only 5 have a validly published epithet. All these species form a well-supported monophyletic group within the genus Sticta, and display interesting patterns of endemism: a single species is present in all islands, while the others are restricted either to Madagascar, to Reunion and Mauritius, or to Reunion only. The estimated divergence time of the radiation of this clade occurred in the upper Miocene, apparently concurrent with the emergence of Mauritius. The tree topology obtained supports an original diversification of the clade in the Mascarenes archipelago rather than in Madagascar. [less ▲]

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See detailLeachate and leonardite Humic substances effect on in vitro root initiation and elongation of woody species
Tahiri, Abdelghani ULg; Destain, Jacqueline ULg; Thonart, Philippe ULg et al

Poster (2016, February 05)

Arise from the chemical and biological degradation of plant and animal residues and from the synthetic activities of microorganisms in the soil, humic substances (HS) are natural heterogeneous aromatic ... [more ▼]

Arise from the chemical and biological degradation of plant and animal residues and from the synthetic activities of microorganisms in the soil, humic substances (HS) are natural heterogeneous aromatic and organic compounds. These substances are chemically complex with no clearly defined chemical structure, although generalized models have been proposed. Present everywhere in the nature; they take part in basic functionalities in any ecosystems involving soils, sediments, water and landfills. They have long been recognized as plant growth promoting substances, particularly with regard to influencing nutrient uptake, root growth and architecture. They influence plant productivity directly by the stimulation of biochemical and metabolic processes or indirectly through the modification of soil characteristics and microflora activities. All together, these properties mainly affect root architecture by inducing root hairs proliferation, differentiating root cells and enhancing lateral root emergence. Experiments targeting the rooting stages in absence of interferences were conducted in vitro using HS extracted from landfill leachate and a stable commercial formulation (“Humifirst” from TRADECORP company: 12% humic acid and fulvic acid 3%) issued from leonardite. Shoots and leaves explants of silver birch (Betula pendula Roth) and black alder (Alnus glutinosa L. Gaertn) explants were treated with 10 ppm of leachate and leonardite HS for 5 days during the rooting induction/initiation phase or during rooting elongation phase. The results obtained show that treatment with a low concentration (10 ppm) during induction/initiation phase may be slightly unfavorable to the formation of roots in alder but not in birch. While, in root elongation phase, there is an increase in the number of roots per shoot only in birch. The direct effects of leachate and leonardite HS on root development vary from one species to another. [less ▲]

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See detailEarly life programming of pigs' intestinal microbiota, intestinal functioning and hepatic metabolism by maternal wheat bran supplementation
Leblois, Julie ULg; Bindelle, Jérôme ULg; Dehareng, Frédéric et al

Poster (2016, February 05)

The gastrointestinal (GI) microbiota plays many roles on the host’s health, acting as a barrier against pathogens and influencing the development and maturation of the mucosa, important for host’s ... [more ▼]

The gastrointestinal (GI) microbiota plays many roles on the host’s health, acting as a barrier against pathogens and influencing the development and maturation of the mucosa, important for host’s immunity. Microbial colonization occurs pre- and postnatally, via maternal transfer i.e. by milk and by the contact with sows faeces. Hence, the early establishment of a beneficial gastrointestinal microbiota in piglets was investigated by supplementing the sows with wheat bran that we consider as a prebiotic (rich in non-starch polysaccharides). Sows were fed either a wheat bran-enriched diet (25% in gestation, 14% in lactation) either a control diet. Piglets were suckling during 4 weeks, receiving a standard creep feed containing no pre- or probiotic from the second week until weaning. The direct effect of wheat bran on the fecal microbial composition of the sow has been analyzed as well as the chemical composition and immunoglobulins content of the colostrum and milk. Sows and piglets growth performances have been recorded at different time points to verify that wheat bran doesn’t impair performances. At weaning, piglets have been euthanized and the impact of the maternal treatment was investigated at different levels: growth performances, ileal and colonic microbiota, intestinal physiology and immunological response and metabolism. A second animal experiment will be performed next year including a metabolic challenge by giving half of the piglets a high-energy diet post-weaning. [less ▲]

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See detailBioncontrol of wheat against Septoria Tritici Blotch: new elicitors
Le Mire, Géraldine ULg; SIAH, Ali; Jijakli, Haissam ULg

Poster (2016, February 05)

Wheat is one of the most cultivated crop plants in the world. However, this plant must constantly face numerous biotic challenges, including major yield losses every year (up to 30-50%) due to a foliar ... [more ▼]

Wheat is one of the most cultivated crop plants in the world. However, this plant must constantly face numerous biotic challenges, including major yield losses every year (up to 30-50%) due to a foliar disease known as Septoria Tritici Blotch (STB). This persistent and harmful disease is caused by the fungus Zymoseptoria tritici. Disease control mainly depends on phytosanitary products. However, conventional agriculture is evolving towards more sustainable practices, out of respect for human health and the environment. Elicitors are considered as promising biological control tools for Integrated Plant Management (IPM) strategies. Contrary to conventional products, these natural compounds do not inhibit directly the pathogen but induce a general and systemic resistance in the plant to a large spectrum of diseases. The natural defense mechanisms of the plant are thus stimulated. Few elicitors have yet been successfully tested and formulated to protect wheat against STB. This study focuses on the screening of ten potential elicitor products of various origins and structures to protect winter wheat against Zymoseptoria tritici. Greenhouse trials were carried out to measure the ability of the different products to reduce disease foliar symptoms (necrosis, chlorosis and pycnidia). In addition, the biocide activity of these products directly towards the pathogen was evaluated under greenhouse and laboratory conditions, respectively. The corresponding results will be presented and discussed with the perspective to choose the best elicitor candidates for field trials and to undertake further investigations on the signaling pathways, and the influence of environmental parameters, on the elicitation capacity. [less ▲]

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See detailMicrodélétions et duplications 22q11.22 distales
PIERQUIN, Geneviève ULg; CABERG, Jean-Hubert ULg; BULK, Saskia ULg

Poster (2016, February 03)

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See detailThe global chemistry climate model ECHAM6-HAMMOZ
Schultz, Martin G.; Franco, Bruno ULg; Kaffashzadeh, Najmeh et al

Poster (2016, February 02)

Atmospheric composition of short-lived gases and aerosols is an important component of the global climate system. Complex processes from emissions, transport, and chemical reactions to heterogeneous loss ... [more ▼]

Atmospheric composition of short-lived gases and aerosols is an important component of the global climate system. Complex processes from emissions, transport, and chemical reactions to heterogeneous loss processes and radiation interactions need to be implemented in climate models to reach an adequate understanding of the role of short-lived climate forcers on the climate system and to allow the assessment of climate impacts on the regional scale. With ECHAM6-HAMMOZ we have developed a comprehensive model of tropospheric and stratospheric aerosols and gas-phase chemistry which is now running successfully on the Jülich supercomputer JURECA. [less ▲]

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See detailOUTDOOR MEASUREMENT OF CATTLE METHANE EMISSIONS USING THE EDDY-COVARIANCE TECHNIQUE IN COMBINATION WITH GEOLOCALIZATION DEVICES
Dumortier, Pierre ULg; Andriamandroso, Andriamasinoro ULg; Aubinet, Marc ULg et al

Poster (2016, February)

Methane emissions account for 8% of the EU-15 GHG emissions and livestock generates approximately half of these emissions [1]. In order to improve emissions reporting and properly test mitigation options ... [more ▼]

Methane emissions account for 8% of the EU-15 GHG emissions and livestock generates approximately half of these emissions [1]. In order to improve emissions reporting and properly test mitigation options, techniques for measuring methane emissions from cattle must be developed and adapted to each management system. Among available micrometeorological methods, the use of eddy-covariance is still in its infancy [2] and its relevance and robustness for cattle flux estimation has still to be proved. On one hand, it is well adapted to seasonal grazing systems, is non-invasive, needs little animal handling and allows detection of daily emission patterns. On the other hand, it has the drawback of requiring cattle geo-localization and long periods of measurements (typically one month). In this study, we combined measured CH4 fluxes with a footprint model [3] and cattle positions (GPS devices) over several one-month campaigns at key periods in the grazing season in order to obtain CH4 emissions per cow at herd scale. Accelerometers were also added to the system for behaviour detection, opening the possibility of linking emissions to feeding behaviour. Measurements were performed and are still ongoing at the Dorinne Terrestrial Observatory in 2014/2015. The first campaign provided a mean emission per cow of 65±6 kg CH4.LSU-1.year-1. Cattle emission pattern was tightly linked with behaviour pattern, emissions being higher during and shortly after grazing (i.e. at dawn and dusk). Uncertainties linked to the method will be discussed and quantified (footprint model validity, geo-localization precision, eddy covariance corrections and filtering specificities linked to CH4 measurements). Compilation of data from multiple campaigns will allow quantification of the effects of forage quality, animal weight and lactating state on emissions per cow. [less ▲]

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See detailNew insights into the fossil record of the mangrove palm Nypa: a taphonomic study from the Iberian Peninsula
Moreno-Dominguez, Rafael; Cascales-Miñana, Borja ULg; Ferrer, Javier et al

Poster (2016, February)

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See detailSciaenops ocellatus: Daily and seasonal sound variation during spawning in aquaculture.
Henry, Séverine ULg; Falguière, Jean Claude; Devillers, Samson et al

Poster (2016, February)

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See detailThe Devonian palynology of the Iberian Península: current state and future goals
Rial, Gonzalo; Diez, José B.; Cascales-Miñana, Borja ULg

Poster (2016, February)

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See detailDiagnosis of sickle cell disease by innovative PCR without DNA extraction
DETEMMERMAN, Liselot; BOEMER, François ULg; OLIVIER, Sabine

Poster (2016, February)

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See detailBibliothEP : a study evaluating the effectiveness of bibliotherapy for
Kempeneers, Philippe ULg; Andrianne, Robert ULg; Bauwens,, Sabrina et al

Poster (2016, February)

Objective. The BibliothEP study aimed to assess the efficacy of a bibliotherapy for premature ejaculation (PE) Design and method. The study was conducted in two phases. First, a sample of 120 participants ... [more ▼]

Objective. The BibliothEP study aimed to assess the efficacy of a bibliotherapy for premature ejaculation (PE) Design and method. The study was conducted in two phases. First, a sample of 120 participants suffering from PE read a concise cognitive behavioural self-help manual for PE (51 A5 pages including illustrations) and were compared after treatment to 66 waiting list controls. Second, 36 subjects received and read the self-help manual and were compared after treatment to 32 subjects having received the same manual plus a complementary brief guidance (45-90 minutes) from a coach not specialised in sex therapy, but who had been specifically trained to support the bibliotherapy intervention (by attending a 5-hour training module). The main outcome measures were selfdetermined latency time to ejaculation, feelings of control, sexual satisfaction, PErelated distress and subjective impression of improvement. Results. At 6-month posttreatment, all participants showed significant improvements as compared to waiting list condition. The improvements were maintained at 12 month. They were slightly greater in the case of complementary therapist support. Improvements were demonstrated for all forms of PE, but the intervention appeared to be slightly more effective when the problem was of moderate severity. In all cases, improvements in sexual functioning were accompanied by improvements in sexual cognitions. Conclusions. The cost-effectiveness of the self-help manual makes it a valuable first-line treatment for any form of PE. Moreover, the outcome of the bibliotherapy process might be increased by coaching from a health worker specifically trained to this aim. [less ▲]

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See detailTwo cases of atypical CALR mutations in MPN patients
SAGOT, Clémence ULg; CHARLIER, Hélène ULg; KOOPMANSCH, Benjamin ULg et al

Poster (2016, January 29)

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See detailSalt but not glucocorticoïds enhances Th17 differentiation from naïve T cells in vitro
Delens, Loïc ULg; SERVAIS, Sophie ULg; Vrancken, Louise et al

Poster (2016, January 29)

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See detailHolocene paleoenvironmental reconstructions from speleothem and peat bog archives
Allan, Mohammed ULg; VERHEYDEN; CRUCIFIX, Michel et al

Poster (2016, January 28)

The geological materials (speleothems and peatbogs) presented in Belgium (Hautes-Fagnes Plateau, Ardennes caves) are interesting archives for atmospheric pollution record and climate variability. Both ... [more ▼]

The geological materials (speleothems and peatbogs) presented in Belgium (Hautes-Fagnes Plateau, Ardennes caves) are interesting archives for atmospheric pollution record and climate variability. Both archives are easily dated (U/Th and counting for laminated speleothems, 210Pb and 14C for peatbogs), have a high temporal resolution (decadal to seasonal), contain multiple measurable parameters (elemental geochemistry, stable isotopes, radiogenic Nd and Pb isotopes, pollens, rates of peat humification, luminescence and thickness of laminated speleothems) and depending on environmental conditions of temperature and / or humidity. The aim of this study is to determine the sensitivity of both archives (speleothems and peatbogs) to human perturbations and climate changes. Our ultimate goal is to contribute to a better understanding of natural interglacial climate variability by generating and confronting high resolution paleoclimate reconstructions from 2 continental archives. [less ▲]

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See detailTreg, Th17 and γδ T cells during normal and abortive pregnancy
Polese, Barbara ULg; Gridelet, Virginie ULg; Munaut, Carine ULg et al

Poster (2016, January 25)

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See detailIdentification of small molecule ligands for the orphan GPCR GPR27
Dupuis, Nadine ULg; Gilissen, Julie; Derj, Anouar ULg et al

Poster (2016, January 25)

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See detailUnravelling the roles of lysine acetylation by Elp3 during inner ear development
Mateo Sanchez, Susana ULg; Delacroix, Laurence ULg; Freeman, Stephen ULg et al

Poster (2016, January 25)

We planned to investigate the role of Elp3 acetyl-transferase, a member of the Elongator complex, in inner ear formation. We first analysed the spatio-temporal pattern of Elp3 mRNA expression and showed ... [more ▼]

We planned to investigate the role of Elp3 acetyl-transferase, a member of the Elongator complex, in inner ear formation. We first analysed the spatio-temporal pattern of Elp3 mRNA expression and showed that it was expressed in the entire early otocyst at E11.5 and persisted later in the sensory epithelium of the cochlea, in the spiral ganglion and in the vestibule. To unravel functions of Elp3, we used conditional knock-out mice in which Elp3 gene is deleted from early otocyst (Elp3cKO). We submitted these mice to a battery of vestibular testing and found significant abnormalities. Besides, the auditory brain stem response of Elp3cKO indicated that these mice are severely deaf. We were also able to demonstrate an increased level of apoptosis in the Elp3cKO spiral ganglion leading to a reduced number of neurons and fibers innervating the sensory cells as well as a reduced number of their synaptic ribbons. Moreover, the remaining spiral ganglion neurons extend processes showing clearly defects regarding sensory cell innervation. In conclusion, our results clearly show a role for Elp3 both in hearing and balance. We plan to go deeper in the mechanisms involved through the identification of the proteins that are targeted for acetylation by Elp3. [less ▲]

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See detailTargeted and random mutagenesis of orphan GPCRs of the SREB family
Laschet, Céline ULg; Dupuis, Nadine ULg; Derj, Anouar ULg et al

Poster (2016, January 25)

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See detailDe novo sequencing using MELD proteolysis coupled to a "sequence assembly" algorithm
Mazzucchelli, Gabriel ULg; Zimmerman, Tyler A; Smargiasso, Nicolas ULg et al

Poster (2016, January 22)

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See detailInsight et expériences anormales du soi dans la schizophrénie : une étude phénoménologique
Englebert, Jérôme ULg; Baillion, Marie

Poster (2016, January 20)

Le terme d'insight désigne la conscience et la compréhension que le malade a de son trouble mental (Raffard, 2007). La prévalence du manque d'insight dans la schizophrénie est élevée puisque 50 à 80% des ... [more ▼]

Le terme d'insight désigne la conscience et la compréhension que le malade a de son trouble mental (Raffard, 2007). La prévalence du manque d'insight dans la schizophrénie est élevée puisque 50 à 80% des patients n'aurait pas conscience de leur maladie (Amador et Gorman, 1998). L'objectif de notre étude est d'investiguer la conscience qu’une personne atteinte de schizophrénie a de ses troubles en utilisant une méthodologie d’inspiration phénoménologique. Pour atteindre notre objectif, nous avons choisi un outil issu des travaux de la psychopathologie phénoménologique. L’échelle EASE [Evaluation des Anomalies de l'Expérience de Soi] (Parnas et al., 2012) permet d'appréhender la conscience des troubles de façon qualitative et selon une perspective en première personne. Nous avons également utilisé le Self-Appraisal of Illness Questionnaire (SAIQ, Marks et al. 2000), permettant l'évaluation de l'insight de manière quantitative. Notre population, composée de sujets schizophrènes, est divisée en deux groupes : ceux ayant un bon insight et ceux ayant un faible (révélés par le SAIQ). Nous avons évalué la conscience des troubles à l'aide de l’EASE chez 14 hommes schizophrènes de 51 ans d’âge moyen. Notre hypothèse était que, plus le sujet peut parler des expériences qu'il vit – donnée qualitative que nous évaluons avec l'échelle EASE qui facilite l'énonciation de ses troubles – plus le sujet a conscience de sa maladie. Les deux tiers de notre échantillon confirment notre hypothèse. Notre étude met en exergue que l’insight est un phénomène difficile à appréhender qui mérite d’être étudié dans une perspective en première personne. Parnas et Henriksen (2014) estiment que l’échec de programmes thérapeutiques et de psychoéducations ainsi que la faible observance de la médication est souvent le résultat d'une compréhension inadéquate de la nature du concept d’insight dans la schizophrénie. [less ▲]

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See detailCorps-pour-autrui et anorexie mentale : une étude étho-phénoménologique
Englebert, Jérôme ULg; Minguet, Eugénie

Poster (2016, January 20)

D’un point de vue phénoménologique, les patientes souffrant d’anorexie mentale semblent confrontées à des perturbations fondamentales au niveau de l’incarnation (embodiment) et de l’intersubjectivité. Par ... [more ▼]

D’un point de vue phénoménologique, les patientes souffrant d’anorexie mentale semblent confrontées à des perturbations fondamentales au niveau de l’incarnation (embodiment) et de l’intersubjectivité. Par conséquent, cette étude évalue les expériences corporelles subjectives de participantes anorexiques à la lumière du concept du corps-pour-autrui de Sartre ainsi que des hypothèses éthologiques de Demaret concernant l’altruisme. Deux hypothèses principales, intrinsèquement liées, structurent cette recherche. La première envisage des difficultés concernant l’intersubjectivité, les patientes anorexiques se définissant davantage à travers le regard des autres et tendant à moins ressentir leur corps de manière sensorielle. La deuxième hypothèse suggère que les anorexiques font preuve de plus d’altruisme, qu’il soit alimentaire ou général. Cet altruisme constituerait un élément central du syndrome anorexique. Pour tester les hypothèses, l’EDI-II (Eating Disorder Inventory), la traduction française du questionnaire IDEA (IDentity and EAting disorder) mesurant le concept du corps-pour-autrui et des questions complémentaires abordant le concept d’altruisme ont été administrées à 67 patientes anorexiques francophones et 246 participantes contrôles ne présentant pas de trouble du comportement alimentaire (TCA). Les résultats des analyses statistiques confirment nettement les deux hypothèses : les patientes anorexiques obtiennent des scores aux questionnaires significativement supérieurs à ceux des participantes contrôles. De façon globale, la psychopathologie anorexique présenterait bien comme signe cardinal des difficultés au niveau de l’incarnation et de l’intersubjectivité. De plus, malgré le fait que les questions relatives à l’altruisme doivent être davantage confirmées et investiguées, les patientes anorexiques se révéleraient nettement plus altruistes que les participantes sans TCA. Nous présenterons également deux brèves analyses de cas qui permettront de mieux comprendre les particularités de l’être-au-monde anorexique. [less ▲]

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See detailAnomalies de l’expérience de soi dans la schizophrénie : Comparaison avec les représentations des proches
Englebert, Jérôme ULg; Lo Presti, Fanny

Poster (2016, January 20)

Notre objectif est de comparer les expériences (inter-)subjectives de personnes souffrant de schizophrénie avec la perception que leurs proches en ont. L'instrument de mesure utilisé est l'échelle EASE ... [more ▼]

Notre objectif est de comparer les expériences (inter-)subjectives de personnes souffrant de schizophrénie avec la perception que leurs proches en ont. L'instrument de mesure utilisé est l'échelle EASE (Évaluation des Anomalies de l’Expérience de Soi) qui permet, dans une orientation phénoménologique, une exploration semi-structurée en première personne des troubles de la conscience de soi. L'échantillon est composé de cinq personnes atteintes de schizophrénie et de cinq proches. Il a été demandé au patient de choisir comme « proche » la personne la plus significative pour lui. L’hypothèse centrale sur laquelle repose notre étude est qu’il existe une différence qualitative entre le discours du patient (perspective en première personne) et les représentations du proche (perspective en troisième personne). Les entrevues semi-structurées se sont déroulées individuellement, d’abord avec le patient, ensuite avec le proche. Les résultats de cette étude qualitative sont nombreux et suggèrent de nombreuses pistes d’analyse. L’une d’elle suggère notamment que les impressions des proches concernant le vécu (inter-)subjectif des patients dépendrait particulièrement de leur connaissance de la maladie de manière générale, de la qualité des échanges avec le patient mais aussi de leur regard/avis concernant la maladie. Nous observons que la communication est nettement plus présente chez les deux binômes de notre échantillon ayant le moins de différence entre les deux discours. De plus, ces deux binômes étaient également composés des deux patients les plus jeunes. Nous pourrions, dès lors, suggérer que les proches seraient plus attentifs au comportement du patient lors des premières phases de la maladie et que leurs démarches pour comprendre cette dernière soient également plus actives. [less ▲]

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See detailRéflexion psychopathologique sur le diagnostic d’héboïdophrénie
Englebert, Jérôme ULg; De Page, Louis

Poster (2016, January 20)

Le concept d’héboïdophrénie a été proposé par Kalhbaum en 1890. S’il parcourt le XXème siècle à travers les grands systèmes nosographiques, il n’obtiendra jamais qu’une place secondaire voire marginale ... [more ▼]

Le concept d’héboïdophrénie a été proposé par Kalhbaum en 1890. S’il parcourt le XXème siècle à travers les grands systèmes nosographiques, il n’obtiendra jamais qu’une place secondaire voire marginale parmi les entités psychopathologiques de référence. Il est d’ailleurs absent des différents DSM (y compris la récente 5ème version). L’on ajoutera que, si elle est née en Allemagne, l’héboïdophrénie a surtout été discutée dans le giron de la psychopathologie française. Cette psychopathologie se caractérise par une symptomatologie psychotique de type schizophrénique et des troubles du comportement de type antisocial. Cette symptomatologie « bicéphale » – d’une part psychotique et d’autre part psychopathique –, a classiquement été associée à la pathogénie de certaines schizophrénies, notamment en incarnant une forme d’entrée typique et précoce dans le trouble. Une hypothèse psychopathologique et compréhensive souvent retenue est que le comportement antisocial pourrait répondre à la gestion difficile de l’angoisse psychotique naissante. L’on peut alors suggérer une interaction et une influence mutuelle entre les pôles antisocial et schizophrénique. La prise en considération de ce diagnostic peut se révéler utile en psychopathologie légale : ces patients interrogent de façon complexe la notion de « responsabilité » et ont souvent, au préalable, échappé aux soins et aux circuits psychiatriques classiques. Nous présenterons plusieurs données cliniques issues de notre pratique, mais également des données empiriques préliminaires. Notre objectif est de montrer qu’une prise en considération de ce diagnostic peut avoir grand intérêt dans le contexte médico-légal dans lequel apparaissent ces patients. C’est, selon nous, grâce à une réflexion psychopathologique approfondie – incluant notamment une analyse des thématiques délirantes, une étude des contextes de formation de ces idées, et sur une prise en considération de l’évolution existentielle du trouble schizophrénique – que les complexes questions de dangerosité et de récidive (le risk), et de thérapeutique, de prise en charge et de réinsertion (le care) pourront être mieux posées. [less ▲]

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See detailÉtude des expériences corporelles anormales dans la schizophrénie
Englebert, Jérôme ULg; Lancellotti, Elisa

Poster (2016, January 20)

L’objectif de notre recherche est l’étude des expériences corporelles anormales (Abnormal Bodily Experiences [ABE]) chez les personnes diagnostiquées schizophrènes. En plus de nous inspirer des résultats ... [more ▼]

L’objectif de notre recherche est l’étude des expériences corporelles anormales (Abnormal Bodily Experiences [ABE]) chez les personnes diagnostiquées schizophrènes. En plus de nous inspirer des résultats de l’étude de Stanghellini et al. (2012), nous nous référerons également au troisième domaine de l’échelle d’Evaluation des Anomalies de l’Expérience de soi [EASE] qui explore spécifiquement les « Expériences corporelles ». Nous suivons une méthode d’analyse dites « empirico-phénoménologique ». Cette dernière est « empirique » car elle se base sur l’analyse des descriptions des expériences et comportements des patients, et « phénoménologique » car l’ensemble des phénomènes décrits est envisagé comme des façons d’entrer en relation avec le monde et autrui. Le questionnaire semi-structuré que nous avons créé est composé de vingt questions comprenant six catégories (seize sous-catégories) : dysmorphies, dépersonnalisation somatique et étrangetés corporelles, objectivations morbides, expériences cénesthésiques, perturbations motrices, expériences mimétiques. Notre échantillon est composé de cinquante sujets schizophrènes hospitalisés. Les entretiens semi-structurés se déroulent en deux parties. Durant la première séance, nous avons administré le questionnaire dont l’ordre varie en fonction des réponses et de l’attitude du patient. Lors de la seconde rencontre, nous faisions un feedback au patient. Cela nous a permis de vérifier la concordance des réponses à travers le temps. À travers l’analyse des résultats, nous observons que les ABE sont des symptômes très présents chez les personnes souffrant de schizophrénie. Nous observons également que toutes les catégories et sous-catégories sont présentent dans notre échantillon. Ces résultats devraient permettre d’affiner et préciser le diagnostic de schizophrénie et d’ouvrir des perspectives concernant la dimension psychothérapeutique. [less ▲]

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See detailComparaison des performances des modèles d'analyse discriminante PLS et SVM
Eylenbosch, Damien ULg; Fernández Pierna, Juan Antonio; Baeten, Vincent et al

Poster (2016, January 19)

Les performances des modèles d’analyses discriminantes PLS (Partial Least Squares) et SVM (Support Vector Machines) ont été comparées dans une étude qui avait pour objectif de discriminer des spectres ... [more ▼]

Les performances des modèles d’analyses discriminantes PLS (Partial Least Squares) et SVM (Support Vector Machines) ont été comparées dans une étude qui avait pour objectif de discriminer des spectres proches infrarouges sur base d'images hyperspectrales de racines et de pailles de froment en vue de les quantifier. [less ▲]

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See detailChemometrics and vibrational spectroscopy for the detection of melamine levels in milk
Fernandez Pierna, Juan; Vincke, Damien; Baeten, Vincent et al

Poster (2016, January 19)

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See detail"Quand voyager mentalement dans le temps est difficile) - Une étude comparative des souvenirs et projections définissant le soi chez des patients dépressifs et des sujets contrôles sains
Wagener, Aurélie ULg; Thirion, Julie; PITCHOT, William ULg et al

Poster (2016, January)

INTRODUCTION. Les patients dépressifs présentent des difficultés à effectuer le voyage mental dans le temps, une des fonctions principales de la mémoire autobiographique, c’est-à-dire à se projeter ... [more ▼]

INTRODUCTION. Les patients dépressifs présentent des difficultés à effectuer le voyage mental dans le temps, une des fonctions principales de la mémoire autobiographique, c’est-à-dire à se projeter mentalement dans le passé et le futur. Cette étude s’intéresse à des événements passés et futurs potentiels particuliers qui sont les souvenirs et les projections futures définissant le soi (SDS et PFDS, respectivement). Les SDS et les PFDS sont des événements autobiographiques particuliers hautement pertinents pour l’identité de l’individu et qui l’aident à se définir. Plus précisément, les SDS sont considérés comme une cristallisation des liens entre mémoire et identité. Le premier objectif de cette étude est d’évaluer les caractéristiques de ces SDS et des PFDS (spécificité, intégration, valence émotionnelle, modification de la valence émotionnelle pour les SDS) chez des patients dépressifs, en comparaison à des sujets contrôles sains. Le second objectif est d’évaluer les liens entre les caractéristiques des SDS et des PFDS avec la clarté du concept de soi. HYPOTHÈSES. Les patients dépressifs rapporteront des SDS et des PFDS moins spécifiques, moins intégrés et plus négatifs que les sujets contrôles sains. Ceci sera en lien avec une faible clarté du concept de soi. MÉTHODE. 19 patients dépressifs et 17 sujets contrôles sains appariés (sexe, âge, niveau d’éducation) ont évoqué des SDS et des PFDS en fonction de domaines de vie (ex. : relations familiales, hobbies, emploi/carrière). RÉSULTATS. La récolte des données est toujours en cours. Les résultats préliminaires mettent en évidence que les patients dépressifs évoquent des SDS et des PFDS moins intégrés que les sujets contrôles. Les patients dépressifs rapportent également davantage de séquence de contamination dans le rappel de SDS (la valence de l’événement lorsqu’il s’est déroulé était positive et devient négative lors de l’évocation du souvenir). DISCUSSION. Les résultats obtenus confirment partiellement nos hypothèses. Ces résultats semblent cohérents avec certains biais préalablement observés dans l’évocation de souvenirs autobiographiques tels que le biais de congruence à l’humeur. Les implications cliniques de ces résultats seront discutées. [less ▲]

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See detailApplication of a standardisation procedure on an international network of MIR instruments for milk analysis
Grelet, Clément ULg; Fernandez Pierna, Juan A.; Dardenne, Pierre et al

Poster (2016, January)

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See detailSingle molecule force spectroscopy on synthetic foldamers
Devaux, Floriane ULg; Li, Xuesong; Ivan, Huc et al

Poster (2016, January)

Inspired by the many folded conformations of the molecular machineries responsible for chemical reactions and mechanical tasks in nature, such as enzyme catalysis and duplication in nucleic acids ... [more ▼]

Inspired by the many folded conformations of the molecular machineries responsible for chemical reactions and mechanical tasks in nature, such as enzyme catalysis and duplication in nucleic acids, chemists have been developing the syntheses of artificial folded molecular architectures, namely foldamers (Guichard and Huc, 2011). The investigation of these molecules using AFM-based Single Molecule Force Spectrosocopy (SMFS) allows the elucidation of both mechanochemical properties and conformational dynamics on the unimolecular scale in solution. The stepwise synthesis of aromatic oligoamide-based foldamers was designed (Jiang et al., 2003; Huc, 2004) to produce well-defined helically-folded molecular architectures. A poly(ethylene oxide) PEO tether was coupled to one end of the foldamer. This tether design enables the coupling with the AFM tip and increases the number of potentially accessible physicochemical parameters through SMFS experiments. SMFS pulling experiments on this system yielded specific and reproducible force-extension patterns characteristic of single foldamers. Those patterns were further analyzed to determine unfolding forces and dynamics as well as to propose mechanistics hypotheses of the unfolding process. Several helical foldamers presenting variable lengths were considered. Experiments in multiple solvents pointed out a variation in the foldamer stability, leading to different average forces values. This last study enabled us to modulate the intramolecular interactions responsible for the folding and to evaluate the mechanochemical properties of the helix. The force values measured for those foldamers are higher than those previously measured in natural biopolymers (Clausen-Schaumann et al., 2000; Janshoff et al., 2000), showing a high stability under a load and a propensity for the development of emergent properties. In addition, the increased stability of these aromatic oligoamide foldamers was confirmed by the observation of almost instantaneous reversibility of the unfolding under load. [less ▲]

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See detailImplications of spatial and temporal variation in point technology in KwaZulu-Natal during the MSA
Bader, Gregor; Porraz, Guillaume; Rots, Veerle ULg et al

Poster (2016)

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See detailCarbon balance of an intensively grazed grassland in southern Belgium
Gourlez de la Motte, Louis ULg; Jérôme, Elisabeth; Mamadou, Ossénatou ULg et al

Poster (2016)

Grasslands are an important component of the global carbon balance but their carbon storage potential is still highly uncertain. Especially, the impact of weather variability and management practices on ... [more ▼]

Grasslands are an important component of the global carbon balance but their carbon storage potential is still highly uncertain. Especially, the impact of weather variability and management practices on grassland carbon budgets need to be assessed. This study investigates the carbon balance of an intensively managed permanent grassland in southern Belgium and its uncertainties by combining 5-years of eddy covariance measurements and other organic carbon exchanges estimates. The specificities of this study lie in: (i) the age of the pasture, which has probably been established since more than one century; (ii) the intensive character of the management with a mean grazing pressure larger than 2 livestock unit ha-1 and stocking cycle including stocking and rest periods, (iii) the livestock production system, typical of Wallonia, farming intensively Belgian Blue breed of cattle in order to produce meat. The results showed that, despite the high stocking rate and the old age of the pasture and the high stocking rate, the site acted as a relatively stable carbon sink from year to year with a 5-year average Net Biome Productivity of ‒173 [‒128 ‒203] g C m-2 yr-1. The carbon sink behavior of the pasture was directly increased by management practices through food complementation and organic fertilization and indirectly by mineral fertilization. The relatively low carbon budget inter-annual variability could be explained both by: (i) grazing management of the farmer that regulated Growth Primary Productivity by adapting the stocking rate to the Leaf Area Index which itself depends on weather conditions, (ii) carbon imports through food complements only when grass regrowth was not sufficient to feed the cattle. An exception occurred when low temperatures at the beginning of the year and a prolonged snow period provoked a delay in grass growth and therefore Growth Primary Productivity that could not be completely offset during the rest of the year. The results suggest that management practices that tend to optimize forage availability for meat production could contribute to maintaining a carbon sink. [less ▲]

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See detailSleep deprivation affects brain global cortical responsiveness
Gaggioni, Giulia ULg; Chellappa; Ly et al

Poster (2016)

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See detailStudy of cell growth on/in modified polymer matrices as scaffolds for tissue engineering
Markvicheva, E.; Drozdova, M.; Demina, T. et al

Poster (2016)

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See detailUnexpected sensitivity of the annual net ecosystem exchange to the high frequency loss corrections in a grazed grassland site in Belgium
Mamadou, Ossénatou ULg; Gourlez de la Motte, Louis ULg; De Ligne, Anne ULg et al

Poster (2016)

The eddy covariance technique is widely used to measure CO2 and other gas fluxes. However, eddy covariance fluxes are affected by systematic errors that must be corrected. Among them, high frequency loss ... [more ▼]

The eddy covariance technique is widely used to measure CO2 and other gas fluxes. However, eddy covariance fluxes are affected by systematic errors that must be corrected. Among them, high frequency loss corrections are particularly important in this regard, especially when using a closed-path infrared gas analyzer. In this study, we compared three approaches to do these corrections for CO2 fluxes and evaluated their impact on the carbon balance an intensively grazed grassland site in Belgium . In the first approach, the computation of correction factors was based on the measured sensible heat cospectra (‘local’ cospectra), whereas the other two were based on theoretical models (Kaimal et al., 1972). The correction approaches were validated by comparing the nighttime eddy covariance CO2 fluxes corrected with each approach and in situ soil respiration measurements. We found that the local cospectra differed from the Kaimal theoretical shape, although the site could not be considered ‘difficult’ (i.e., fairly flat, homogeneous, low vegetation, sufficient measurement height), appearing less peaked in the inertial subrange. This difference greatly affected the correction factor, especially for night fluxes. Night fluxes measured by eddy covariance were found to be in good accord with in situ soil respiration measurements when corrected with local cospectra and to be overestimated when corrected with Kaimal cospectra. As the difference between correction factors was larger in stable than unstable conditions, this acts as a selective systematic error and has an important impact on annual fluxes. On the basis of a 4-year average, at DTO the errors reach 71-150 g C m-2 y-1 for net ecosystem exchange (NEE), 280-562 g C m-2 y-1 for total ecosystem respiration (TER) and 209-412 g C m-2 y-1 for gross primary productivity (GPP), depending on the approach used. We finally encourage site PIs to check the cospectrum shape at their sites and, if necessary, compute frequency correction factors on the basis of local cospectra rather than on Kaimal cospectra. [less ▲]

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See detailResting-state test-retest reliability over different preprocessing steps
Varikuti, Deepthi; Hoffstaedter, Felix; Genon, Sarah ULg et al

Poster (2016)

Introduction: Resting-state (RS) functional connectivity (FC) analysis has become a widely used method for the investigation of human brain connectivity and pathology. While most of the current ... [more ▼]

Introduction: Resting-state (RS) functional connectivity (FC) analysis has become a widely used method for the investigation of human brain connectivity and pathology. While most of the current applications are based on data-driven analyses, the use of functionally specific, a priori defined networks provided by neuroimaging meta-analyses represent an important alternative to these, as they allow the standardized assessment of connectivity patterns. Neuronal activity as measured by functional MRI is influenced by various nuisance signals including system noise, thermal noise, and noise induced by physiological processes of the participant. The presence of these confounds in turn have an impact on the estimation of functional connectivity. Several methods exist to deal with this predicament, but little consensus has yet been reached on the most appropriate approach. Given the crucial importance of reliability for the development of clinical applications, we investigated the test-retest reliability of FC analyses in meta-analytically defined networks after removing confounding noise regressors. Methods: RS-fMRI data of 42 healthy subjects with an average age of 42 ± 20 years were obtained in two sessions with an average time interval of 175 ± 75 days. A seed-based FC analysis was conducted after spatial preprocessing, approach specific confound-regression, and band-pass filtering [0.01-0.08 Hz]. We focused on the effects of various commonly used confound removals in the resting state studies such as PCA de-noising, global mean signal regression, and removal of tissue-class specific mean signals (in particular, white matter (WM) + cerebrospinal fluid (CSF) and WM + CSF + grey matter (GM)) [2,3,4,5,7]. Additionally, we examined GM specific time-series extraction from seed regions. In order to compute the seed based FC, a priori defined networks were analyzed (extended socio-affective default mode [1] and working-memory [6]). Both networks show robust within network resting state connectivity as well as anti-correlation between each other. The reliability of FC was measured using two different measures Spearman correlations and the absolute differences of functional connectivity scores. The different approaches defined by the combination of different masking / confound removal approaches were compared using a non-parametric Friedman ANOVA. Results: The summary ranking across both indices of reliability (Spearman correlations and absolute differences) reflects the major patterns noted in the individual analyses (Fig.1). GM masking, in particular using the group-mean segmentation, improves reliability. PCA denoising in turn reduces it. Within-network connections are most reliably estimated when not using any global or tissue-class specific signal regression, with removing the global WM and CSF signals representing the next-best approach. In contrast, between-network connections are most reliably measured by linear and second order removal of global signals of all three-tissue classes. Conclusion: Our results show that GM masking of the seed regions based on the group-average GM probabilities is advisable when investigating meta-analytically defined networks. In turn, PCA de-noising reduces the reliability of connectivity estimates. Finally, with respect to global signal regression, we observe that refraining from this approach enhances reliability, but comes at the expense of potentially poorer biological validity, indicated by missing anti-correlations between what has been previously described as antagonistic networks. Here, removal of global WM and CSF signals seems to provide a good compromise, as this approach yielded reliable and meaningful estimates of within and between-network connections (Fig.2). We noted that reliability is proportional to the retained variance, presumably including structured noise. Consequently, we would argue that compromises are needed between maximizing reliability and removing variance that may be attributable to non-neuronal sources. [less ▲]

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See detailModelling children’s mobility and school commuting: a review and key challenges for further research
Marique, Anne-Françoise ULg; Teller, Jacques ULg; Cools, Mario ULg

Poster (2016)

Children’s mobility and school travelling are relatively underdeveloped in transport research, especially when compared with commuting to work. Despite it is often argued that a profound analysis of ... [more ▼]

Children’s mobility and school travelling are relatively underdeveloped in transport research, especially when compared with commuting to work. Despite it is often argued that a profound analysis of school-travel patterns has the potential to generate many important insights that may impact transport-system policy and management, the modelling of children mobility, is still in an early stage of development and children are often only considered as constraints to adults’ mobility. In this paper, we argue that innovative modelling frameworks that were recently developed in the field of transportation could be adapted and applied to the mobility of children in order to develop both novel scientific insights and inform the development of policies aiming at increasing active and independent mobility of children, in a broader vision of sustainability. [less ▲]

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See detailMultimodal evidence of a rostro-caudal and ventro-dorsal organization in the dorsal premotor cortex
Genon, Sarah ULg; Li, Hai; Fan, Lingzhong et al

Poster (2016)

Introduction Different methods for in-vivo characterization have resulted in different maps of the human dorsal premotor cortex (PMd): Task-based functional studies suggested a rostro-caudal gradient ... [more ▼]

Introduction Different methods for in-vivo characterization have resulted in different maps of the human dorsal premotor cortex (PMd): Task-based functional studies suggested a rostro-caudal gradient corresponding to a cognitive-motor gradient1,2 and mapping based on resting-state functional connectivity (RSFC) likewise suggested a subdivision along the rostro-caudal axis3. In contrast, mapping based on structural connectivity as assessed by probabilistic diffusion tractography (PDT) provided evidence that the dorsal part of the precentral gyrus (PG) is organized along a ventro-dorsal axis4. However, there is currently no multimodal mapping of a broadly defined PMd. The present study used a multimodal approach to (1) identify a robust topographical organization of the right PMd by using connectivity-based parcellation (CBP) applied to a meta-analytic approach of task-related coactivation data (i.e. meta-analytic connectivity modeling, MACM5,6), and (2) examine whether the thus obtained parcellation pattern would be reproduced by CBP based on two other connectivity modalities: unconstrained functional (as reflected by RSFC) and structural as measured by PDT based on diffusion-weighted imaging (DWI). Methods A volume of interest (VOI) was defined by merging PMd activation sites from several meta-analyses serving as robust functional localizers of the PMd while excluding primary sensorimotor areas. MACM-CBP6 was performed using Brainmap database. RSFC-CBP and PDT-CBP were performed on distinct datasets to ensure independent parcellation7. RSFC-CBP was computed on RS data of 124 healthy subjects (age: 39.5 ± 11.5 yrs., 66 males) from the 1000BRAINS project8. The voxels’ time series (TS) were first cleaned from confounding effects using PCA denoising and global signal regression. RSFC was then computed by Pearson correlations between the TS of the VOI voxels and those of the rest of the brain. PDT-CBP9 was performed on DWI data of 20 healthy subjects (age: 18.5 ± .76, 10 males) using FSL. Several cluster solutions (k solution) were examined with k-means for MACM- and RSFC-CBP and spectral clustering for PDT-CBP. The choice of the k solution was driven by task-based functional data (MACM) based on three criteria: variation of information, percentage of deviants, and silhouette value6. Results The selected criteria jointly identified the 5-cluster (5k) solution as optimal across the range of functional studies from Brainmap database (Figure 1). Examination of stability across subjects following PDT-CBP further suggested that k=5 may be considered a local optimum within 2 ≤ k ≤ 6. This solution revealed a similar pattern of topographical organization across modalities (Figure 2) with a subdivision along both rostro-caudal and ventro-dorsal axes, including a rostral cluster lying mainly anteriorly to the PG, a central one at the intersection of the precentral sulcus and the superior frontal gyrus, a caudal one in the posterior part of the PG, a ventral one adjacent to ventral PM, and a dorsal one adjacent to the inter-hemispheric premotor areas. Discussion For the first time our study revealed that the PMd could be divided along two axes: rostro-caudal and ventro-dorsal. This is consistent with previous functional2 and microstructure studies10 in humans and non-human primates suggesting a rostro-caudal distinction and with a previous PDT-CBP of the (dorsal) precentral gyrus4 showing that it could be subdivided in the ventro-dorsal direction. Importantly, this topographical organization was found in the independent analysis of three different connectivity aspects: task functional, unconstrained functional and structural, each based on different datasets. In sum, different modalities consistently show that the PMd can be subdivided into 5 subregions organized along both rostro-caudal and ventro-dorsal axes, comprehensively integrating patterns previously revealed by different methods. [less ▲]

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See detailImpact of estetrol on breast cancer development, metastatic dissemination and angiogenesis
Gallez, Anne ULg; Gérard, Céline ULg; BLACHER, Silvia ULg et al

Poster (2016)

The increased risk of breast cancer and thromboembolism in women who take Hormone Replacement Therapy (HRT) currently is a major public health problem. The discovery of novel molecules with better safety ... [more ▼]

The increased risk of breast cancer and thromboembolism in women who take Hormone Replacement Therapy (HRT) currently is a major public health problem. The discovery of novel molecules with better safety profile would provide useful advances for patient care. Estretrol (E4) appears as a promising candidate for HRT. Indeed, in contrast to current treatment containing ethinyl estradiol or estradiol (E2), E4 has a minimal impact on liver cells activity supporting a decreased incidence on thromboembolic events. In preclinical studies, E4 has been effective against the main symptoms of menopause such as hot flushes, vaginal atrophy, and osteoporosis, from a starting dose of 0.3 mg/kg/day. The aim of this study was to define the impact of E4 on breast cancer development when it is used at concentrations effective for menopause symptom relief. Treatment of estrogen receptor (ER)-positive breast cancer-developing mice (MMTV-PyMT) with several concentrations of E4 has shown that 0.3 mg/kg/day E4 did not increase tumor development and metastasis dissemination. However, at 3mg/kg/day, E4 increased the growth of hormone-dependent tumors and their metastatic dissemination in ovariectomized and intact mice. This effect was similar to the one observed with E2 used at 0.08 mg/kg/day. In an in vivo model of ER-negative tumors, we observed that 3mg/kg/day E4 improved tumor growth by increasing angiogenesis, and subsequently decreasing necrosis and tumor hypoxia. In contrast, 0.3 mg/kg/day E4 did not induce any of these effects on ER-negative tumors and tumor microenvironment. In conclusion, we have shown that 0.3 mg/kg/day E4, already reported to prevent menopause symptoms, does not increase breast tumor growth, metastasis dissemination, and angiogenesis. However, similarly to E2, higher concentrations of E4 are pro-tumorous. These results support that E4, if it is used in strictly controlled clinical applications, could have no or only limited impact on breast cancer. [less ▲]

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See detailCystatin C standardization decreases assay variation and improves assessment of GFR
Ebert, N; DELANAYE, Pierre ULg; Shlipak, M et al

Poster (2016)

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See detailComparison of commercial membranes tailored as 3D in vitro cell models
Romano, Ilaria ULg; Tilkin, Rémi ULg; Hubaux, Roland et al

Poster (2016)

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See detailChanges in the structure and the composition of microtubules within supporting cells of the organ of hearing during development.
Renauld, Justine ULg; Freeman, Stephen ULg; Thelen, Nicolas ULg et al

Poster (2016)

The auditory organ is a highly specialized structure composed by specific cellular types. The sensory cells are characterized by stereocilia at their apex and are necessary for the sound perception. These ... [more ▼]

The auditory organ is a highly specialized structure composed by specific cellular types. The sensory cells are characterized by stereocilia at their apex and are necessary for the sound perception. These cells are supported by supporting cells which contain up to 3000 microtubules and are formed by 15protofilaments (15pf) instead of the canonical 13, a unique fact among vertebrates. It was shown that a β-tubulin isoform can specify the microtubule architecture, such as the expression of the Moth β2 in the Drosophila testes imposed the 16pf structure on the corresponding subset of Drosophila microtubules, which normally contain 13pf. To determine the role of these tubulins in the auditory organ and their possible involvement in the formation of the unusual 15pf microtubules of supporting cells, we studied the spatiotemporal localization of five -tubulin isotypes (β1 to 5) as well as acetyl-α-tubulin within the hearing organ during development in rodents. By using confocal microscopy, we showed that with the exception of the β3-tubulin isoform that was specific to nerve fibres, all the different β-tubulin isoforms and acetyl-α-tubulin were mainly present in the supporting cells. Contrary to β1-4-tubulins, we also found that the β5-tubulin isoform appeared only at a key stage of the postnatal development. By using transmission electron microscopy, we examined the fine structure of microtubules at an early and a late postnatal stage. Our TEM study indicated that these cells are composed by 13pf microtubules at P2, but by 15pf microtubules at P25. We revealed further that this developmental stage coincide with the formation of two separate bundles of microtubules from a unique one in these supporting cells. In conclusion, the architecture and composition of microtubules present in the supporting cells change during development of the organ of Corti. Further experiments are now required to determine if these changes are related to the appearance of β5-tubulin. [less ▲]

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See detailCharacterisation of a secondary carotenoid producer microalga of the genus Coelastrella
Corato, Amélie ULg

Poster (2016)

Some green microalgae synthesize secondary carotenoids as protecting agents under stress. These pigments have high value as feed supplement for aquaculture and as health products. The most promising ... [more ▼]

Some green microalgae synthesize secondary carotenoids as protecting agents under stress. These pigments have high value as feed supplement for aquaculture and as health products. The most promising pigment is astaxanthin, because of its antioxidant, antitumoral and anti-inflamatory properties. The most used natural source of this pigment is the microalga Haematococcus pluvialis. However this species grows slowly and lacks robustness for easy cultivation. Therefore, other species are investigated for astaxanthin production. Here, we identified a locally isolated strain as Coelastrella sp. that is a secondary carotenoid producer. [1] A known typical feature of this genus, that we could observed in the strain by scanning electron microcopy, is the presence of meridional ribs. [2] We analyzed the culture conditions and concluded that this strain grows both autotrophically and heterotrophically and is able of fast change in pigment composition under controlled stress conditions. Thanks to HPLC analyses, we determined that the strain accumulates a variety of secondary carotenoids, among which: astaxanthin, cantaxanthin and echinenone. Unidentified compounds will be further analyzed by mass spectrometry. [less ▲]

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See detailThe effect of aging on associative memory for semantically-related word pairs
Folville, Adrien; Delhaye, Emma ULg; Bastin, Christine ULg

Poster (2016)

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See detailIngénierie des ambiances urbaines: développement d'un dispositif pédagogique mixant approche numérique et créativité
Nguyen, Ngoc Luan ULg; Reiter, Sigrid ULg

Poster (2016)

Le présent poster décrit le dispositif pédagogique mis en œuvre pour accompagner les étudiants dans la conception et l’évaluation d’ambiances urbaines grâce à la combinaison d’un apprentissage par projet ... [more ▼]

Le présent poster décrit le dispositif pédagogique mis en œuvre pour accompagner les étudiants dans la conception et l’évaluation d’ambiances urbaines grâce à la combinaison d’un apprentissage par projet et de la modélisation numérique des projets développés à l’échelle du quartier. Cette activité de formation répond aux sept critères essentiels d’une situation-problème en apprentissage par projet. Ce poster résume l’expérience accumulée dans l’application de ce dispositif pédagogique innovant. [less ▲]

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See detailProteomic landscapes of Pachycondila villosa ant venom by nano-scale chromatography and high resolution mass spectrometry
Cologna Takeno, Camila; Degueldre, Michel; Shibao, Priscilla et al

Poster (2016)

Introduction: It is estimated that the total number of molecules present in animal venoms is a collection of 40 million different compounds and, despite the efforts made, less than 0,01% of those ... [more ▼]

Introduction: It is estimated that the total number of molecules present in animal venoms is a collection of 40 million different compounds and, despite the efforts made, less than 0,01% of those compounds was identified and characterized to date. However, recent progresses in proteomic, in parallel with the advances of mass spectrometry have contributed to the study of those bio-libraries. The sensitivity improvement of these instruments allows the study of minimal amounts of sample still yielding a wealth of information. The present work aimed to perform a deep proteomic analysis of the venom from the ant Pachycondilyla villosa focusing on the de novo sequencing and the characterization of post translational modifications using high resolution mass spectrometers. Methods: The crude venom (0,5 ug) of P. villosa ants collected on Panga Natural Reserve (Uberlandia-Minas Gerais- Brazil) was diluted in 0,2% of formic acid and injected into a nanoACQUITY ULPC equipped with a monolithic PepSwift Capillary column 100µm x 25, hyphened to a Q Exactive Orbitrap mass spectrometer. The elution of the compounds was performed with a gradient of 3 to 50% of solution B in 80 minutes (A: H2O/FA 0.1%; B: ACN) at flow rate of 1 µL/min. All mass spectrometry analyses were performed in data dependent analysis (DDA) mode that automatically triggers the MS/MS experiments. The top 10 most intense peaks of each MS scan was fragmented by high-energy dissociation (HCD) and their corresponding MS/MS spectra were acquired. Preliminary data: Animal venoms are considered a rich source of biologically active compounds, which has been constantly selected and refined by the processes of natural evolution, in which each molecule is endowed with pharmacological properties highly valuable for scientific purposes. Despite the commitment, the exploration of these bio-libraries remains limited which might be related to the technological limitations that prevent full-scale investigation of these venoms. In addition, the conventional methods used to explore animal venoms are still time-consuming and require large amounts of samples, which restrict the studies for a few species. Unquestionably, the advances of proteomics and mass spectrometry instrumentations benefited a great deal the research on hymenoptera venom. Mostly due to their small size and therefore scarcely collected venom, this order has always been neglected and considered unfeasible to be studied through the known strategies. The present work represents the first report concerning the venom composition of P. villosa ant. The preliminary results already highlight the complexity of this venom, which showed to be composed by over 5000 different molecules. Most of those components fall into the 800- 4000 Da range, which is in agreement with other studies regarding ant´s venom composition. Most of the proteomics studies concerning ant venoms already revealed the presence of linear peptides below 5000 Da as major components. Those small peptides usually display antimicrobial activity and some of them hold additional insecticidal activity. Novel aspect: The results obtained already point out the biotechnological potential of P. villosa venom and highlight’s its complexity [less ▲]

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See detailThe Influence of the Perceived School Climate on Adolescents' Academic Achievement: Testing the Mediating Role of Intrinsic School Motivation
Vaillancourt, Marie-Claire; Blanchette-Luong, Vanessa; Véronneau, Marie-Hélène et al

Poster (2016)

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See detailImpacts of wheel traffic on the physical properties of a Luvisol under reduced and conventional tillage
Saur, Marie-Laure ULg; Destain, Marie-France ULg; Roisin, Christian et al

Poster (2016)

Soil compaction is a complex mechanism which results in a decrease of soil porosity and an increase of soil strength. Such effects may reduce crop yield since they are harmful for root growth, germination ... [more ▼]

Soil compaction is a complex mechanism which results in a decrease of soil porosity and an increase of soil strength. Such effects may reduce crop yield since they are harmful for root growth, germination, mesofauna and bacterial life. Soil compaction may also reduce hydraulic conductivity which increases the risk of runoff, contamination of surface water, erosion and emission of greenhouse gases due to anaerobic processes. In the context of sustainable agriculture, it is crucial to characterise the impact of the agricultural techniques on the compaction state in the arable layer due to machine traffic. For this purpose, Soil samples were taken in a Luvisol at different depths, on plots under longterm reduced tillage (RT) and conventional tillage (CT). The impact of wheel traffic on the physical properties of the soils was also studied. The experimental approach consists in measuring traditional macroscopic soil properties such as bulk density and precompression stress, and combining them with pore size distribution obtained by mercury intrusion porosimetry. Automatic cone index measurements were initially performed to map the soil resistance and easily identify the sampling depths. The measurements revealed a plough pan at 30-cm depth under both CT and RT. Nevertheless, the subsoil under RT showed pieces of evidence of a natural regeneration process of the microporosity. The impact of wheel traffic was studied in RT and CT plots. It was shown that the passage of heavy machine such as beet harvester coupled to water content close to the optimum proctor is clearly unfavourable in terms of compaction. The measurements revealed large modifications of soil structure in the topsoil of CT, whereas the soil structure slightly changes through depth. However, the latter remains the more problematic case since the soil will not be loosened by tillage anymore, resulting in strongly compacted soil years after years. In addition to the experimental approach, numerical modelling was used in order to predict the soil compaction. A finite element method was used and the soil behaviour was modelled by an elastoplastic law (modified Cam-Clay model). The model parameters were calibrated from the experimental measurements. The simulations allowed to compare the porosity and the surface deformation after wheel traffic with the experiments. The variations of machine weight and tyre pressure were numerically studied and it was showed that the machine weight has an influence in the topsoil and the subsoil, whereas the tyre pressure affects only the topsoil. [less ▲]

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See detailThe Fractal Nature of Mars Topography Analyzed via the Wavelet Leaders Method
Kleyntssens, Thomas ULg; Deliège, Adrien ULg; Nicolay, Samuel ULg

Poster (2016)

This work studies the scaling properties of Mars topography based on Mars Orbiter Laser Altimeter (MOLA) data through the wavelet leaders method (WLM). This approach shows a scale break at 15 km. At small ... [more ▼]

This work studies the scaling properties of Mars topography based on Mars Orbiter Laser Altimeter (MOLA) data through the wavelet leaders method (WLM). This approach shows a scale break at 15 km. At small scales, these topographic profiles display a monofractal behavior while a multifractal nature is observed at large scales. The scaling exponents are greater at small scales. They also seem to be influenced by latitude and may indicate a slight anisotropy in topography. [less ▲]

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See detailGalectin-1 is involved in osteoclast biology
Muller, Joséphine ULg; Binsfeld, Marilène; DUBOIS, Sophie ULg et al

Poster (2016)

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See detailSemantic relatedness of the memoranda prevents older adults from benefitting from unitization
Delhaye, Emma ULg; Tibon, Roni; Gronau, Nurit et al

Poster (2016)

Detailed reference viewed: 44 (4 ULg)