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See detailarchiDART: a R package allowing root system architecture analysis using Data Analysis of Root Tracings (DART) output files
Delory, Benjamin ULg; Baudson, Caroline ULg; Brostaux, Yves ULg et al

Poster (2014, February 07)

In 2010, Le Bot et al presented a free and open-access software (Data Analysis of Root Tracings - DART) allowing the analysis of complex root system architectures from captured images, particularly across ... [more ▼]

In 2010, Le Bot et al presented a free and open-access software (Data Analysis of Root Tracings - DART) allowing the analysis of complex root system architectures from captured images, particularly across time series. Using this software, a user has to manually identify roots as a set of links. After vectorization of a root system, three final data sets (RAC, TPS and LIE) can be exported as table files containing several attributes for (a) each individual root (e.g. root length), (b) each observation day or (c) each point used to construct the vectorized root system respectively. These data sets can finally be used either to calculate derived root system architecture (RSA) parameters or to draw the root system architecture at selected observation dates. However when an experiment involves the analysis and comparison of many root systems, the calculation of RSA parameters for each data set and the drawing of the corresponding vectorized root systems become time-consuming. In this context, we developed a R package, called archiDART, allowing both the automatic calculation of common root architecture parameters and the X-Y plotting of vectorized root systems for selected observation dates. [less ▲]

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See detailSimulations of a beta amphiphilic peptide as potential surfactant of membrane proteins
Crowet, Jean-Marc ULg; Dony, Nicolas ULg; Deschamps, Antoine et al

Poster (2014, February 07)

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

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

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

Poster (2014, February 07)

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

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

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

Poster (2014, February 07)

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

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

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See detailInteractions between new phenolic glycolipids and model membrane
Sainvitu, Pauline ULg; Nasir, Mehmet Nail ULg; Crowet, Jean-Marc ULg et al

Poster (2014, February 07)

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

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

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

Poster (2014, February 07)

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

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

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

Poster (2014, February 07)

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

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

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

Poster (2014, February 07)

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

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

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

Poster (2014, February 07)

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

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

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See detailRhizobacterial volatile organic compounds implication in Brachypodium distachyon response to phosphorus deficiency
Baudson, Caroline ULg; Saunier de Cazenave-Mendaluk, Magdalena ULg; du Jardin, Patrick ULg et al

Poster (2014, February 07)

In agriculture, phosphorus (P) is considered as the second most growth-limiting macronutrient after nitrogen. However, P fertilizers are produced from non-renewable resources. In this context, sustainable ... [more ▼]

In agriculture, phosphorus (P) is considered as the second most growth-limiting macronutrient after nitrogen. However, P fertilizers are produced from non-renewable resources. In this context, sustainable production strategies have to be developed to enhance P use efficiency of crops, e.g. based on naturally occurring biotic interactions that limit the negative impacts of P deficiency in soils. Plant growth-promoting rhizobacteria (PGPR) have already revealed their ability to promote plant growth and tolerance to abiotic stresses through many mechanisms. Among them, the bacterial volatile organic compounds-mediated communication between plants and PGPR is still poorly documented. Our research project aims at studying the capacity of a model cereal plant (Brachypodium distachyon (L.) Beauv. Bd21) to face P deficiency in interaction with PGPR. The prerequisite of this project consists in characterizing Bd21 response to P deficiency by measuring plant biomass production and allocation, root system architecture, total phosphorus content, root-secreted and intracellular acid phosphatase activity under various P concentrations. Those results will allow us to define P-limiting conditions, in order to assess PGPR volatiles influence on plant response to P deficiency. This approach will use an ex-vitro co-cultivation system allowing volatiles-mediated interaction and should help us to unravel the ability of rhizobacterial volatiles to enhance plant tolerance to P deficiency. [less ▲]

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

Poster (2014, February 07)

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

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

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

Poster (2014, February 07)

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

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

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

Poster (2014, February 07)

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

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

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

Poster (2014, February 07)

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

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

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

Poster (2014, February 07)

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

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

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See detailAllelopathic potential of sunflower against the great brome
Bouhaouel, Imen ULg; Gfeller, Aurélie; Fauconnier, Marie-Laure ULg et al

Poster (2014, February 06)

Control methods commonly used to suppress the great brome (Bromus diandrus Roth., syn. Bromus rigidus Roth. subsp. gussonii Parl.) in Tunisian cereal crop are essentially chemical, raising both efficacy ... [more ▼]

Control methods commonly used to suppress the great brome (Bromus diandrus Roth., syn. Bromus rigidus Roth. subsp. gussonii Parl.) in Tunisian cereal crop are essentially chemical, raising both efficacy and safety issues. The introduction of allelopathic species into the crop rotation or utilizing allelopathic plants as living/green mulches has been suggested as a cost-effective way to reduce the weed presence. Among these species, the sunflower (Helianthus annuus L.) has shown an allelopathic potential against some troublesome weed species. In this study, we analyzed the biological activities of water extract of different tissues (root, shoot, leaf and flower) of sunflower on the seedling establishment of the great brome. In a second experiment, the allelopathic influence of sunflower residues (leaf or flower) against this weed was also studied under glasshouse conditions at more advanced stages of growth using different concentrations (0, 6, 12 and 18g tissue dry weight / kg of soil). The first experiment showed an effect depending on the parts of the sunflower. Indeed, the roots seem to be the less allelopathic part (22% of root inhibition growth) as compared to the leaves and flowers (82% and 100%, respectively). This potential seems to simultaneously affect the radicle and the coleoptile growth of the great brome. In the second experiment, weed growth was inhibited in a dose-dependent manner, using increasing amounts of sunflower residues. The allelopathic potential of the leaves or flowers reduced both the root or shoot length and biomass accumulation of the weed. These results suggest that the sunflower can be a good previous crop for cereal cultivation by controlling the presence of some weeds, including the great brome. In this perspective, the inhibitory effects of sunflower residues on cultivated cereals in the field need to be assessed. [less ▲]

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See detailPaleoenvironmental record of the Amik Basin (Amuq Plain, Southern Turkey) over the last 4000 years
Hubert, Aurelia ULg; El Ouahabi, Meriam ULg; Lebeau, Hélène ULg et al

Poster (2014, February 04)

Continous human occupation is attested in the Amik Basin since 6000-7000 BC. The low-lying Amuq plain is covered by tell settlements first explored by Robert Braidwood in the 1930s. The Basin also is ... [more ▼]

Continous human occupation is attested in the Amik Basin since 6000-7000 BC. The low-lying Amuq plain is covered by tell settlements first explored by Robert Braidwood in the 1930s. The Basin also is crossed by The Dead Sea Fault (DSF), a major neotectonic structure in the Middle East extending from the Red Sea in the south to Turkey in the north. The study focuses on the sedimentary record of the Amik Lake occupying the central part of the Basin. Our objective is to constrain major paleo-environmental changes in the area over the last 4000 years and assess possible human impact. The lake has been drained and progressively dried up since the mid-50s so that it is not watered during the summer season and constitutes a unique opportunity to collect sediment records. Sediments were collected at 1 cm to 2 cm intervals in a trench and in cores up to a depth of 5 meters in the clay deposits. A diverse array of complementary methods is applied to study the records: magnetic susceptibility, grain size, organic matter and inorganic carbon (L.O.I), XRD mineralogy, XRF geochemistry, carbon geochemistry. The age of the record is constrained combining radionuclide and radiocarbon dating. The record shows two intense phases of soil erosion with enrichments in Chromium and Nickel. The most recent erosion phase might be linked with enhanced development during the Roman and the growth of the Antioch City. The oldest one would occur around 3000 BC. The record also allows reconstructing past lake level variations and discusses the results in comparison with variations of the Dead Sea. [less ▲]

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See detailImportance of recent extreme weather variation in Djibouti and need for impact quantification
Nour Ayeh, Moustapha; Mahamoud, Ayan; Saad, Osman et al

Poster (2014, February)

This analysis shows that the current rainfall deficit is exceptional and historically unique. The significant population migration induced by the drought to Djibouti city must be supervised, especially ... [more ▼]

This analysis shows that the current rainfall deficit is exceptional and historically unique. The significant population migration induced by the drought to Djibouti city must be supervised, especially during their spontaneous settling. This presented example confirms that current rainfall shortages and increasing temperature extremes are impactinglocal people who urgently need adaptation and DRR strategies. It is necessary to reduce exposure to hydrological risks of these affected populations, in order that victims of the drought are not carried away by a rainfall excess. [less ▲]

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See detailExploration on structure activity relation of natural, self-assembling cyclic lipodepsipeptides
Geudens, Niels; Feher, Kristina; De Vleeschouwer, Matthias et al

Poster (2014, February)

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See detailSoil Seed Bank : a poorly know component of forest regeneration
Douh, Chauvelin ULg; Daïnou, Kasso ULg; Fernandez Pierna, Juan-Antonio et al

Poster (2014, February)

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See detailCan a global dynamic vegetation model be used for both grassland and crop modeling at the local scale?
Minet, Julien ULg; Tychon, Bernard ULg; Jacquemin, Ingrid ULg et al

Poster (2014, February)

We report on the use of a dynamic vegetation model, CARAIB, within two modeling exercises in the framework of MACSUR. CARAIB is a physically-based, mechanistic model that calculates the carbon ... [more ▼]

We report on the use of a dynamic vegetation model, CARAIB, within two modeling exercises in the framework of MACSUR. CARAIB is a physically-based, mechanistic model that calculates the carbon assimilation of the vegetation as a function of the soil and climatic conditions. Within MACSUR, it was used in the model intercomparison exercises for grassland and crop modeling, in the LiveM 2.4 and CropM WP4 tasks, respectively. For grassland modeling, blind model runs at 11 locations were performed for various time ranges (few years). For crop modeling, a sensitivity analysis for building impact response surfaces (IRS) was performed, based on a bench of model runs at different levels of perturbation in the temperature and precipitation input data over 30 years. For grassland modeling, specific management functions accounting for the cutting or grazing of the grass were added to the model, in the framework of the MACSUR intercomparison. Initially developed for modeling the carbon dynamics of the natural vegetation, CARAIB was already adapted for crop modeling but further modifications regarding the management, i.e., yearly-dependent sowing dates, were introduced. For grassland modeling, simulation results will be further intercompared with other modeling groups, but preliminary results showed that the model could cope with the introduction of the grass cutting module. For crop modeling, building the IRS over 30 years permitted to assess the sensitivity of the model to temperature and precipitation changes. So far, the participation of CARAIB in the intercomparison exercises within MACSUR resulted in further improvements of the model by introducing new functionalities. [less ▲]

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See detailIMPACT OF COVER CROP MANAGEMENT ON CROP PRODUCTION: A FIELD EXPERIMENT IN WALLONIA CONTEXT
Hiel, Marie-Pierre ULg; Bodson, Bernard ULg

Poster (2014, February)

Minimal soil tillage methods, crop rotation, cover crop and continuous plant residue cover are the main pillars of sustainable agriculture. Lower energy consumption, costs and time are some direct ... [more ▼]

Minimal soil tillage methods, crop rotation, cover crop and continuous plant residue cover are the main pillars of sustainable agriculture. Lower energy consumption, costs and time are some direct benefits in favor to the adaptation of this agriculture. This practices aims also directly at protecting the soil from wind and water erosion by covering the soil. Lower disruption of the soil aims at developping the micro- and macro-fauna activity that increases soil fertility and carbon and nitrogen sequestration in soils. Unfortunately, some of the great constraints to the adaptation of conservation agriculture remain weed management, fungal diseases and pest management, that has been shown to be a problem in non-ploughed fields. The aim of our study is to evaluate, on a same field (Wallonia context), contrasted tillage methods for managing the cover crop and the implantation of the main crop. The following measurements were taken: germination rate, root and shoot biomass development, root notation (size and shape), leaf area index and quality of harvested product. Preliminary results indicate that the different tillage methods did not have a significant impact on crop production or development. However changes in germination dynamics were observed, the reduced tillage inducing slower germination. Regarding weeds populations, some difference were observed in weed occurrences. Since a field exp [less ▲]

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See detailControl of phytoplankton bloom by winter conditions in a Mediterranean coastal area : results from a long–term study (1979–2011)
Goffart, Anne ULg; Hecq, Jean-Henri ULg; Legendre, Louis

Poster (2014, February)

The occurrence of a late-winter (February-March) phytoplankton bloom is one of the most unifying features of Mediterranean pelagic ecosystems. However, very little is known about the mechanisms that ... [more ▼]

The occurrence of a late-winter (February-March) phytoplankton bloom is one of the most unifying features of Mediterranean pelagic ecosystems. However, very little is known about the mechanisms that regulate the interannual variability of this phytoplankton bloom in coastal areas. In the present study, we show how winter physical forcing and environmental drivers control surface phytoplankton bloom dynamics in terms of the onset of the bloom, its duration, and its intensity through the analysis of a long-term time series (1979-2011) at the oligotrophic PhytoCly station (Bay of Calvi, Corsica, northwestern Mediterranean). We define a winter intensity index (WII) that integrates wind forcing and water temperature, and discuss strong correlations between WII and both surface nutrient fertilization and phytoplankton bloom intensity. Our study is consistent with reports that phytoplankton blooms can develop in homogenous water columns, and it does not fit the conventional idea that phytoplankton are blooming in temperate oceans because of warming/stratification of the surface layer. [less ▲]

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See detailNew alternatives to chemical pesticides: deciphering the action mechanisms of lipid based plant elicitors via complementary biophysical and biological approaches.
Nasir, Mehmet Nail ULg; Polo Lozano, Damien ULg; Luzuriaga Loaiza, Walter ULg et al

Poster (2014, February)

Nowadays, many health and environmental problems are caused by the use of chemical pesticides. In this context, an increasing demand for alternative products such as biopesticides has been observed. Among ... [more ▼]

Nowadays, many health and environmental problems are caused by the use of chemical pesticides. In this context, an increasing demand for alternative products such as biopesticides has been observed. Among biopesticides, elicitor molecules which are able to trigger immune defense responses in plants are one of the most promising options. Although numerous elicitors have been discovered, the mechanisms involved in the perception, by plants, of only a few molecules have been identified. These elicitors usually interact with proteic receptors but we have recently shown that they may also act on the lipid phase of the plasma membrane. This project first aims to improve our understanding of the molecular mechanisms involved in the recognition of specific lipid based elicitors (LBE). On that basis, the FIELD project will contribute to the design and the development of innovative compounds derived natural LBE. A multi-disciplinary approach, based on chemistry, bio-physics, bio-chemistry, and phytopathology will be followed by a consortium of different research groups from Gembloux Agro-Bio Tech in close collaboration with teams from foreign institutions. [less ▲]

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See detailAnthropogenic effects on African Landscapes: Spatial Structure, Typologies, Ecological Impact
Vranken, Isabelle ULg

Poster (2014, February)

The problematique of anthropogenic disturbance on African landscapes is studied within the double framework of DPSIR (Drivers Pressures States Impact Response) and Pattern/Process Paradygm (Landscape ... [more ▼]

The problematique of anthropogenic disturbance on African landscapes is studied within the double framework of DPSIR (Drivers Pressures States Impact Response) and Pattern/Process Paradygm (Landscape Ecology). 20 landscae images from D.R. Congo, Ivory Coast and Benin were studied using indexes of spatial (compositional and configurational) heterogeneity and anthropogenic disturbance in order to highlight the relationship between spatial structure and disturbance intensity. The results show maximal heterogeneity at intermediate anthropogenic disturbances and fasten the triangular relationship between anthropogenic effect, biodiversity and spatial heterogeneity, that had been partially theoretised with the intermidiate disturbance and habitat heterogeneity hypotheses. [less ▲]

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See detailBayesian methods for predicting and modelling winter wheat biomass
Mansouri, Majdi ULg; Dumont, Benjamin ULg; Destain, Marie-France ULg

Poster (2014, February)

The objectives of this paper are threefold. The first objective is to propose to use an Improved Particle Filtering (IPF) based on minimizing Kullback-Leibler divergence for crop models' predictions. The ... [more ▼]

The objectives of this paper are threefold. The first objective is to propose to use an Improved Particle Filtering (IPF) based on minimizing Kullback-Leibler divergence for crop models' predictions. The performances of the proposed technique are compared with those of the conventional Particle Filtering (PF) for improving nonlinear crop model predictions. The main novelty of this task is to develop a Bayesian algorithm for nonlinear and non-Gaussian state and parameter estimation with better proposal distribution. The second objective is to investigate the effects of practical challenges on the performances of state estimation algorithms PF and IPF. Such practical challenges include (i) the effect of measurement noise on the estimation performances and (ii) the number of states and parameters to be estimated. The third objective is to use the state estimation techniques PF and IPF for updating prediction of nonlinear crop model in order to predict winter wheat biomass. PF and IPF are applied at a dynamic crop model with the aim to predict a state variable, namely the winter wheat biomass, and to estimate several model parameters. Furthermore, the effect of measurement noise (e.g., different signal-to-noise ratios) on the performances of PF and IPF is investigated. The results of the comparative studies show that the IPF provides a significant improvement over the PF because, unlike the PF which depends on the choice of sampling distribution used to estimate the posterior distribution, the IPF yields an optimum choice of the sampling distribution, which also accounts for the observed data. [less ▲]

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See detailMicrofluidic on optical fibers: Towards a new kind of fluorescent biosensor
Lismont, Marjorie ULg; Vandewalle, Nicolas ULg; Weyer, Floriane ULg et al

Poster (2014, February)

In recent works, the behavior of droplets moving along vertical treads due to gravity was studied. It appeared that the droplet can be stopped by encountering a horizontal fiber depending on droplet ... [more ▼]

In recent works, the behavior of droplets moving along vertical treads due to gravity was studied. It appeared that the droplet can be stopped by encountering a horizontal fiber depending on droplet volumes and fiber characteristics. On the basis of this behavior and by replacing treads by two crossed optical fibers, it is possible to combine fluidics and optics to develop a new kind of fluorescent sensor. In our work, the intersection between two crossed optical fibers is used as the basic unit of an original optofluidic biosensor. These two optical fibers are used as droplets carriers: one for probe molecules and the other one for target species. The fiber's junction catches the droplets and act as a reaction center. The main advantage of using optical fibers resides in their ability to propagate and collect light to and from the droplet localized at the fiber's crossing. This optical fiber configuration can therefore allow the study of biological interactions using fluorescent labels. This new and versatile detection scheme was validated on a calcium indicator where ions detection is accomplished by using a dye, Oregon green Bapta-2, that has a Ca 2+ recognition group as well as an entity exhibiting fluorescence. A FRET recognition event, between Rh-Con A and FITC-Dextran, was also investigated to detect glucose. Finally, a prototype of a multiplexing device, composed of several juxtaposed fibers' junctions, was developed. [less ▲]

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See detailImmunomodulatory effects of Rapamycin in xenogeneic GVHD
Ehx, Grégory ULg

Poster (2014, January 31)

Graft-versus-host disease (GVHD) remains a major cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (HSCT). Several studies have shown that rapamycin (RAPA), an mTOR ... [more ▼]

Graft-versus-host disease (GVHD) remains a major cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (HSCT). Several studies have shown that rapamycin (RAPA), an mTOR inhibitor with immunosuppressive properties, may reduce GVHD severity and mortality, notably by favoring regulatory T cells (Tregs) proliferation in vivo and in vitro. However, very few data have been reported about the global impact of this drug on the immune system in the context of GVHD. The present work investigates the cellular mechanisms by which RAPA delays death from xenogeneic GVHD induced by peripheral blood mononuclear cells infusion in NSG mice. Our results show that RAPA injections significantly delay death from xenogeneic GVHD and reduce disease severity. Flow cytometric analyses highlighted a strong reduction of human cells chimerism in mice together with higher CD4+/CD8+ T cells balance due to a lower proliferation of CD8+ T cells. In addition, the frequencies of naive CD4+ and CD8+ T cells were higher and the CD4+ T cells showed a reduced effector phenotype (CD45RO+CD27-). Tregs were positively affected as RAPA up-regulated their expression of Bcl-2 and Ki67 as well as their STAT5 phosphorylation level, leading to higher Treg frequency in treated mice. Altogether these data demonstrate that RAPA delays xenogeneic GVHD by lowering human chimerism and effector CD4+ frequency as well as promoting Tregs. [less ▲]

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See detailL'oxydation des poudres: un défi pour l'avenir
Blecker, Christophe ULg

Poster (2014, January 27)

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See detailScikit-Learn: Machine Learning in the Python ecosystem
Joly, Arnaud ULg; Louppe, Gilles ULg

Poster (2014, January 27)

The scikit-learn project is an increasingly popular machine learning library written in Python. It is designed to be simple and efficient, useful to both experts and non-experts, and reusable in a variety ... [more ▼]

The scikit-learn project is an increasingly popular machine learning library written in Python. It is designed to be simple and efficient, useful to both experts and non-experts, and reusable in a variety of contexts. The primary aim of the project is to provide a compendium of efficient implementations of classic, well-established machine learning algorithms. Among other things, it includes classical supervised and unsupervised learning algorithms, tools for model evaluation and selection, as well as tools for data preprocessing and feature engineering. This presentation will illustrate the use of scikit-learn as a component of the larger scientific Python environment to solve complex data analysis tasks. Examples will include end-to-end workflows based on powerful and popular algorithms in the library. Among others, we will show how to use out-of-core learning with on-the-fly feature extraction to tackle very large natural language processing tasks, how to exploit an IPython cluster for distributed cross-validation, or how to build and use random forests to explore biological data. [less ▲]

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See detailGIGA ANIMAL CARE : Mice & Zebrafish Animal Facility and Transgenesis
Remy, Benoît ULg; Ectors, Fabien ULg; Winandy, Marie ULg et al

Poster (2014, January 27)

In fundamental research, animal models allow to place molecular and cellular observations back into their physiological context. In applied research, these models still remain a mandatory step to evaluate ... [more ▼]

In fundamental research, animal models allow to place molecular and cellular observations back into their physiological context. In applied research, these models still remain a mandatory step to evaluate the efficiency and the toxicity of potential treatments, before going to clinical trials. Mouse and Zebrafish (Danio rerio) are two very interesting models because of a short live cycle and a high prolificacy. They require a limited space. Their genome is well known and shows a high homology with the human. Many tools are available to produce transgenic mice or zebrafishes. Many tests are validated using both these species. [less ▲]

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See detailImmunomodulatory effects of Rapamycin in xenogeneic GVHD
Ehx, Grégory ULg; HANNON, Muriel ULg; DUBOIS, Sophie ULg et al

Poster (2014, January 27)

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See detailCryopreservation of embryos : a way to reduce the number of housed animals and the genetic drift.
Remy, Benoît ULg; Ectors, Fabien ULg; Drion, Pierre ULg

Poster (2014, January 27)

The GIGA Mouse facility platform has recently improved its mouse line cryopreservation technique. The method of embryo cryopreservation by rapid cooling also called aseptic vitrification has been selected ... [more ▼]

The GIGA Mouse facility platform has recently improved its mouse line cryopreservation technique. The method of embryo cryopreservation by rapid cooling also called aseptic vitrification has been selected. Vitrification media, key steps and timing have been optimized and validated. After a first partial exposition of the embryos to cryoprotective solutions, they are immersed in a vitrifying mixture of penetrating and non-penetrating cryoprotectants for a short time. The straw containing the embryos is immediately sealed before to be plunged in LN2, resulting in a brutal solidification in which crystallization does not have time to occur. [less ▲]

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See detailDUSP3/VHR is a pro-angiogenic atypical dual-specificity phosphatase
Amand, Mathieu ULg; Erpicum, Charlotte ULg; BAJOU, Khalid ULg et al

Poster (2014, January 27)

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See detailGenome-wide association interaction analysis for Alzheimer’s disease.
Gusareva, Elena ULg; Bellenguez, C; Cuyvers, E et al

Poster (2014, January 27)

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See detailKisspeptin and neuronal nitric oxide signaling are important in female sexual behavior
Hellier, Vincent ULg; Bakker, Julie

Poster (2014, January 27)

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See detailArt et schizophrénie : étude comparative de biographies d’artistes d’art brut et de sujets schizophrènes peintres
Moffarts, Aloïse; Englebert, Jérôme ULg

Poster (2014, January 22)

La psychopathologie phénoménologique explique la schizophrénie en termes de perte de l'évidence naturelle (Blankenburg, 1991/1971) ou de psychopathologie du sens commun (Stanghellini, 2000, 2004, 2007 ... [more ▼]

La psychopathologie phénoménologique explique la schizophrénie en termes de perte de l'évidence naturelle (Blankenburg, 1991/1971) ou de psychopathologie du sens commun (Stanghellini, 2000, 2004, 2007). Concernant les théories consacrées à l'art et la psychopathologie, nous nous penchons sur la théorie de la Gestaltung de Prinzhorn (1984), sur l’hypothèse de l’« l'art révolutionnaire » de Sass (1992 ; Spaniol, 2001) et analysons la classification de Jádi (Hulak, 1990). Enfin, à partir de ces travaux, nous avons établi trois types d'art qui peuvent se retrouver chez des artistes malades mentaux : art brut, art naïf et art de recherche. Notre méthodologie consiste à analyser la biographie de deux artistes peintres de la famille de « l'art brut » (Aloïse Cobraz et Adolf Wölfli) en les comparant aux biographies et analyses de cas de deux patients schizophrènes se considérant comme artistes peintres. Nous avons élaboré un questionnaire semi-structuré pour questionner les artistes sur leur parcours artistique et leur rapport à l’art. Après nos analyses et le croisement avec les théories existantes, nous émettons comme hypothèse que les schizophrènes artistes se distinguent des autres types d’artistes (pathologiques ou non) dans leur rapport à la créativité. Ceci est congruent avec le concept d’« art révolutionnaire » de Sass (1992). La classification de Jádi nous permet de suggérer qu’il n’est pas cohérent de parler d’un art des malades mentaux et que le trouble psychiatrique ne peut donc pas être considéré comme l’essence de l'art brut. Enfin, nous pouvons émettre l’hypothèse que l'art semble conférer aux schizophrènes artistes une forme d'adaptation sociale eu égard au sens commun « perdu ». [less ▲]

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See detailLe Rorschach selon le Système Intégré et le TCI-R : comparaison et intégration
Rentmeister, Daniel; Englebert, Jérôme ULg; Blavier, Adelaïde ULg

Poster (2014, January 22)

Pour cette étude, un double objectif est recherché. Premièrement, nous comparons statistiquement le test de Rorschach selon le Système Intégré de J.E.Exner et le Temperament and Character Inventory – ... [more ▼]

Pour cette étude, un double objectif est recherché. Premièrement, nous comparons statistiquement le test de Rorschach selon le Système Intégré de J.E.Exner et le Temperament and Character Inventory – Revised de R. Cloninger afin de mettre en évidence leurs divergences et convergences. Deuxièmement, à l’aide de cas cliniques, nous discutons de la pertinence de l’intégration des résultats obtenus par ces deux outils en vue d’établir le profil psychologique complet et cohérent d’un individu. Pour la comparaison statistique, notre échantillon de 27 sujets tout-venant (M = 24,37 ans ; SD = 2,75) a d’abord été soumis au test de Rorschach. Directement après, chaque sujet a complété le TCI-R. Une analyse de corrélation (Rho de Pearson) a été calculée entre les indices et un ajustement de Bonferroni a été effectué. Pour l’analyse de cas, 3 sujets cliniques ont été recrutés. Une anamnèse a été réalisée et le test de Rorschach et TCI-R administré. Nos premiers résultats, qui sont à prendre avec prudence au vu du faible nombre de sujet de l’échantillon, sont à nuancer et discuter. À partir de 2016 comparaisons statistiques, nous sélectionnons les résultats les plus pertinents et discutons des différentes corrélations observées. Les analyses de cas nous montrent une concordance au niveau des relations sociales et de l’impulsivité ; et nous montrent que les informations propres à chaque test permettent de compléter le profil du sujet. Enfin, c’est en abordant les deux épistémologies différentes sur lesquelles reposent ces deux tests que nous pouvons expliquer au mieux les différences psychologiques mises en évidence à propos des mêmes individus. Nous concluons en suggérant que cette différence de résultats doit certainement être comprise selon une logique intégrative et souligne la complémentarité existant entre ces deux épreuves. [less ▲]

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See detailLe problème des protocoles longs au test de Rorschach
Dufour, Cristelle; Englebert, Jérôme ULg

Poster (2014, January 22)

Notre étude s’intéresse aux protocoles exceptionnellement longs (supérieurs à 50 réponses) fournis par cinq sujets au test du Rorschach administré et interprété selon la méthode du Système Intégré (Exner ... [more ▼]

Notre étude s’intéresse aux protocoles exceptionnellement longs (supérieurs à 50 réponses) fournis par cinq sujets au test du Rorschach administré et interprété selon la méthode du Système Intégré (Exner, 2003). Afin de mieux comprendre quelle attitude adopter face à ce type de protocole, nous avons effectué une réduction a posteriori du nombre de réponses en nous basant sur les recommandations d’Exner (1988, 1992, 2003). Nous avons ensuite réalisé une étude comparative entre l’interprétation clinique réalisée avec la totalité des réponses et avec seulement les cinq premières réponses par planche. Nous avons également reproduit cette méthodologie de réduction a posteriori du nombre de réponses avec quatre réponses par planche en nous inspirant des nouvelles recommandations du système R-PAS de Meyer et al. (2009). Selon ces propositions, un protocole de test de Rorschach serait valide lorsque le sujet fournit entre 20 et 40 réponses (entre 2 et 4 par planche). L’échantillon est composé de trois sujets tout-venant et deux sujets psychiatriques. Notre analyse a mis en évidence une stabilité de certaines variables (EB, Lambda, EA) mais d’importantes différences dans le profil psychologique des sujets après réduction. Nous avons observé une clarification des difficultés fondamentales chez les sujets psychiatriques et plutôt une neutralisation de ces difficultés pour les sujets tout-venant, avec notamment des stratégies défensives qui apparaissent plus adaptées. Selon les résultats obtenus à partir de notre échantillon, nous pouvons suggérer que la prise en compte de la totalité des réponses ou seulement du protocole partiel induit une différence dans l’interprétation clinique. En conséquence, toute réduction du nombre de réponses devrait se faire avec grande prudence. Notre étude permet de discuter des pratiques actuelles du test de Rorschach, en faisant dialoguer les contraintes inhérentes à la validité du test et les questions de la réduction de la complexité clinique propres à toute entreprise de standardisation. [less ▲]

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See detail“A QUICK HIGH BEFORE IMMERSION INTO THE DEEP BLUE: THE FALL OF ICARUS REVISED.”
Lopez-Rodrigez, Alicia; BRASSEUR, Edmond ULg; GHUYSEN, Alexandre ULg et al

Poster (2014, January 18)

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See detailDE L’AIR DANS LA VESSIE?
TAMBWE RAMAZANI, Willy ULg; BRASSEUR, Edmond ULg; Johnson, S et al

Poster (2014, January 18)

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See detailAN UNUSUAL CERVICALGY.
PIAZZA, Justine ULg; BRASSEUR, Edmond ULg; Ghuysen, Alexandre ULg et al

Poster (2014, January 18)

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See detailDendroecology and Dendroclimatology of a Tasmanian Bog Forest
Balanzategui, Daniel; Copenheaver, Carolyn; Frank, David et al

Poster (2014, January 14)

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See detailDepression and autobiographical memory: which are the characteristics of depressed patients' self-defining memories?
Wagener, Aurélie ULg; Weigend, Alicia; Boulanger, Marie ULg et al

Poster (2014, January 13)

BACKGROUND. Depressed patients suffer from autobiographical memory deficits. Indeed, depressed patients present an overgeneralization and a mood congruence biases. Moreover, they seem to have difficulties ... [more ▼]

BACKGROUND. Depressed patients suffer from autobiographical memory deficits. Indeed, depressed patients present an overgeneralization and a mood congruence biases. Moreover, they seem to have difficulties to recall positive memories. Our aim is to focus on a specific kind of memories called “self-defining memories” (SDM) which are highly pertinent for self-building. Their characteristics (e.g. specificity, meaning making) were assessed and compared to those of healthy subjects. HYPOTHESES. Depressed patients relate less specific and meaning making events than control group. A mood congruence bias is observed. METHOD. 17 depressed patients and 18 healthy subjects fulfilled SDM exercises: subjects were asked to relate six important events that happened in their life. These SDM were assessed on several variables: specificity, impact, meaning making, contain. Moreover, subjects were assessed on depression severity and self-esteem (explicit and implicit). RESULTS. No difference between depressed patients and healthy subjects has been found for specificity. A marginal effect appeared for meaning making: control group seemed to relate more meaning making events than depressed patients. Depressed patients related more negative events than control group: this negative emotional valence was positively correlated with higher depression severity. Depressed subjects presented a lower explicit self-esteem than healthy subjects but no difference has been found for implicit self-esteem. Higher explicit self-esteem was positively correlated with positive emotional valence of SDM. DISCUSSION. Results partially support our hypotheses. Experimental and clinical implications of our results will be discussed. [less ▲]

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See detailSelves Impairment in Bipolar Disorder through Self-Concept Clarity, Self-Defining Memories and Self-Esteem
Wagener, Aurélie ULg; Boulanger, Marie ULg; Van Limbergen, Coralie et al

Poster (2014, January 13)

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See detailFunctional traits and speciation of tropical African species: the case of genus Guibourtia Benn
Tosso, Dji-ndé Félicien ULg; Daïnou, Kasso ULg; Hardy, J. Olivier et al

Poster (2014, January 07)

Nowadays, comparative ecology approach is widely used to understand mechanisms of speciation. In evolutionary biology, few studies take into account the importance of physiological traits as criteria for ... [more ▼]

Nowadays, comparative ecology approach is widely used to understand mechanisms of speciation. In evolutionary biology, few studies take into account the importance of physiological traits as criteria for interspecific differentiation, although such an approach is particularly suited to infer the adaptive capacities of taxa. The genus Guibourtia Benn (Fabaceae / Caesalpinioideae), composed of 13 species in Africa, seems an ideal candidate for this study. As a matter of fact, this model includes not only species of different vegetation ecosystems (forest and savanna) but also morphologically very similar species found in various areas with different climates and soils (sandy, clayloam, limestone, hydromorph). Addressing speciation issues, our study seeks to test the hypothesis that populations of closely related species should be studied in terms of both functional traits and phylogeny. In this research, two questions are asked: (i) what are the phylogenetic differences within the genus Guibourtia? (ii) To what extent phylogeny, functional traits and bioclimatic envelope are linked? The results of the study will help to realize the distribution modeling of different evolutionary units of Guibourtia using a dynamic vegetation model (CARAIB) in order to propose strategies for conservation and sustainable management in the context of Central African forests. [less ▲]

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See detailPromotor specific regulation of NF-kappaB mediated transcription by the phosphorylation of p65 on Ser547.
Trussart, Charlotte; Orban, Tanguy; Sabatel, Hélène ULg et al

Poster (2014, January)

NF-kappaB (p50/p65) is an important regulator of gene transcription as it controls the expression of hundred of genes involved in inflammatory and innate responses, proliferation, survival, cancer ... [more ▼]

NF-kappaB (p50/p65) is an important regulator of gene transcription as it controls the expression of hundred of genes involved in inflammatory and innate responses, proliferation, survival, cancer initiation and progression. Several modes of NF-kappaB activation are known among which the classical pathway induced by pro-inflammatory cytokines and a complex atypical pathway induced by DNA damage. Both pathways converge on the IKK activation. The stimulidependent p65 phosphorylation on several serine can control its transcriptional potential either globally or often in a gene specific manner. Lately, we have reported a direct interaction between p65 and ATM and the in vitro phosphorylation of Ser547 by this kinase. A comparative transcriptomic analysis performed in HEK-293 cells expressing either p65WT or p65S547A identified several differentially transcribed genes (IL8, A20, SELE…) after an Etoposide treatment. Substitution of Ser547 to Ala does not affect p65 binding on the kappaB site of the IL8 promoter but it reduces p65 interaction with HDAC1 leading to a higher level of histone H3 acetylated on Lys9 and therefore a higher gene induction. These data indicate that ATM regulates a sub-set of NF-kappaB dependent genes after a genotoxic stress by direct phosphorylation of p65 (1). We are now investigating the impact of the S547A mutation in the context of an inflammatory response. Mefs p65KO expressing recombinant p65WT or p65S547A were treated with TNFalpha. No differences were observed in the kinetic of degradation of IkBa or the nuclear translocation of p65. The level of transcription of a few selected genes is presently under investigation. Contrary to another study, we did not observed any role of ATM in NF-kappaB activation by TNFalpha [less ▲]

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See detailMelanoma AntiGEn D2 (MAGED2) a new partner of the DNA damage response?
Pirlot, Céline ULg; Piette, Jacques ULg; Habraken, Yvette ULg

Poster (2014, January)

MAGED2 belongs to the Melanoma AntiGEn (MAGE) family of proteins. It is ubiquitously expressed and its overexpression in many cancers could make it a potential biomarker of tumor development and ... [more ▼]

MAGED2 belongs to the Melanoma AntiGEn (MAGE) family of proteins. It is ubiquitously expressed and its overexpression in many cancers could make it a potential biomarker of tumor development and metastasis formation. Actually, the only known function of this protein is its involvement in the p53 pathways. Indeed, MAGED2 could be a negative regulator of p53 and it increases apoptosis induced by TRAIL in a p53 dependent manner. Moreover, a phosphoproteomic experiment has shown that this protein is likely phosphorylated by ATM, ATR or DNA-PK after exposition to ionizing irradiation. These three kinases are implicated in the DNA damage response (DDR). Our lab showed by yeast two hybrids an interaction between MAGED2 and ATM. Thus, the aims of the project are to confirm and to find the function of this interaction in a DDR context. Current avenues of investigations include determining the impact of MAGED2 depletion and overexpression in the p53, NF-kappaB and cell cycle regulation following double strand break induced by etoposide treatment. Though this study we plan to confirm a new partner of ATM in the DDR pathway, which could be targeted to limit cancer progression and improve the chemotherapy relying on DNA damaging compounds. [less ▲]

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See detailSeasonal variation in human executive brain responses
Meyer, Christelle ULg; Jaspar, Mathieu ULg; Muto, Vincenzo ULg et al

Poster (2014)

It is well established that cognition shows daily fluctuations with changes in circadian phase and sleep pressure. The physiological impact of season changes, which is well characterized in animals ... [more ▼]

It is well established that cognition shows daily fluctuations with changes in circadian phase and sleep pressure. The physiological impact of season changes, which is well characterized in animals, remains largely unexplored in human. Here we investigated the impact of seasonal variation on human cognitive brain function. This cross-sectional study,conducted in Liège (Belgium),spanned from May 2010 to October 2011. Following 8h in-lab baseline night of sleep, 30 volunteers (age 20.9+1.5; 15F)spent 42h awake under constant routine conditions(<5lux, semi-recumbent position, no time-cues). After12h recovery night, they underwent15minfMRI recording while performing a working memory 3-back task (3b) and a letter detection 0-back task (0b). Thus, fMRI data were acquired when volunteers had been in isolation under controlled conditionsfor 63h. Executive brain responses were isolated by subtracting 0b activity from 3b responses (3b>0b).Analysis tested seasonal influence on executive brain responses at the random effects level, using a phasoranalysis across the year.Inferences were conducted at p<0.05, after correction for multiple comparisons over a priori small volume of interest. Significanteffects of season on executive responses were detected inmiddle frontal and frontopolarregions, insula, and thalamus, with a maximum response at the end of summer and a minimum response at the end of winter.These brain areas are key regions for executive control and alertness. These results constitute the first demonstration that seasonality directly impacts on human cognitive brain functions. [less ▲]

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See detailOptimization of cricket breeding production system for human food in Ratanakiri province (Cambodia)
Caparros Megido, Rudy ULg; Alabi, Taofic ULg; Nieus, Clément et al

Poster (2014)

Despite many natural resources, Cambodia is considered as a relatively poor country with a Gross National Income per capita averaging about 880 USD in 2012. Annâdya project in the Ratanakiri province ... [more ▼]

Despite many natural resources, Cambodia is considered as a relatively poor country with a Gross National Income per capita averaging about 880 USD in 2012. Annâdya project in the Ratanakiri province (Cambodia) aims to improve the food security and nutrition of smallholder households by introducing and facilitating the adoption of productive and environmentally sustainable agricultural technologies. The main purpose of this work was to optimize a cheap cricket breeding production system for local farmers to contribute to the reduction of protein deficiency and to create new source of incomes. Cricket development, Teleogryllus testaceus (Walker), was compared between seven diets composed of different ratio of aerial parts of taro, young cassava leaves, young cashew leaves, brown rice flour (with or without the addition of banana slices) and between the traditionally used chicken feed diet. Cricket mortality was relatively low on all diets (<10 %) excepted on the two cashew-based diets where mortality achieves 90 %. Mean adult body mass of the cricket was significantly higher on control diet (chicken feed) and on the two cassava-based diet (80% of cassava leave flour, 20% of brown rice with or without banana slices) than on the other diets (F = 20.87, P<0.001). The nutritional analyzes of the seven diets shows that the ideal diet should contain 19% protein, 5-6% fat, and a percentage of carbohydrates as high as possible. While the cricket mass body gain seems to be proportional to the carbohydrate content of the diet, the use of older cassava leaves, more rich in carbohydrates than the younger ones, is an interesting solution to substitute relatively expensive brown rice and banana slices also consumed by local population. In the future, consideration should be given to the adjustment of cassava leave maturity in function of the cricket growth stage as it is already done with chicken feed in Thai cricket farms. [less ▲]

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See detailSituation and perspective of entomophagy in Kinshasa
Nsevolo, Papy; Caparros Megido, Rudy ULg; Blecker, Christophe ULg et al

Poster (2014)

Eating edible insects in Republic Democratic of Congo is a tradition for centuries but a lack of knowledge remains about an actualized inventory of species consumed in the country. Moreover, a rigorous ... [more ▼]

Eating edible insects in Republic Democratic of Congo is a tradition for centuries but a lack of knowledge remains about an actualized inventory of species consumed in the country. Moreover, a rigorous taxonomic matching of the used vernacular name of edible insects and a precise characterization of the sector of entomophagy are still needed. According to our studies focused on the city of Kinshasa, 14 edible species were inventoried as regularly consumed. They belong respectively and by degree of importance to the Lepidoptera (46.7%), Isoptera (18.6%), Orthoptera (17.6%), Coleoptera (9.7%) and Hymenoptera (3.7%) orders. Generally 80.0% of the Kinshasa population consumes at least one species of insects 5 days per month. The key peoples in the edible insect sector are mostly women. The incomes generated by this activity contribute to the well being of households, to reduce poverty and food insecurity in the capital Kinshasa. Future studies should focus on sustainable ways of harvesting wild populations, the use of improved conservation practices, the enhancement of cottage industries for farming insects and the development of economically feasible ways of mass-rearing edible species. [less ▲]

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See detailWhen children’s metamemory knowledge and strategic time monitoring predict prospective memory performance
Geurten, Marie ULg; Lejeune, Caroline ULg; Leriche, Charline et al

Poster (2014)

Objective: This study examines the effect of metamemory knowledge, strategic time monitoring, and ongoing task difficulty on children’s prospective memory (PM). Method: Children (aged of 4, 6, and 9) were ... [more ▼]

Objective: This study examines the effect of metamemory knowledge, strategic time monitoring, and ongoing task difficulty on children’s prospective memory (PM). Method: Children (aged of 4, 6, and 9) were given a task inspired by the mirror training paradigm while they performed a time-based memory task. Half of the participants (expert group) were trained to the ongoing activity before the PM test. Results: PM was shown to be predicted by strategic time monitoring. Influence of metamemory knowledge on children’s strategic time monitoring was demonstrated in the expert group. Non-experts’ strategic time monitoring was shown to be predicted only by their ongoing task performance. Conclusion: The implication of metacognitive processes in PM is discussed in the context of the multiprocess framework. [less ▲]

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See detailModelling Farmers Credit Allocation Decisions and Impacts on Farms Technical Efficiency in Benin, West Africa
Sossou, Comlan ULg; Noma, Freddy; Yabi, Jacob

Poster (2014)

This paper models farmers credit allocation behaviours in schemes and analyses effects of the schemes on farms technical efficiency. Data were collected from 476 farmers using the multistage sampling ... [more ▼]

This paper models farmers credit allocation behaviours in schemes and analyses effects of the schemes on farms technical efficiency. Data were collected from 476 farmers using the multistage sampling procedure. The stochastic frontier truncated-normal with conditional mean model was used to assess allocation schemes effects on farms technical efficiency. A Tobit model reveals the impact of farmers' socio-demographic characteristics on efficiency scores. Results revealed that the revenue 2,262,566 Fcfa is positively correlated with acreage, quantity of labour and costs of fertilisers, insecticides, fertilisers. The average technical efficiency score is 0.675 (±0.137). The scores are diversely distributed across farms, with a median score equals to 0.713. Farmers behaviours respond to six credit investments schemes, which are categorised in two allocation contexts: in-farm and out-farm allocations. In the latter credit is invested towards social needs (weddings, traditional festivals, etc.) and household needs (health, education, housing etc.). Credit in-farm allocations are towards production inputs (land, labour, capital). The model showed that only one scheme impacted positively farms technical efficiency: scheme (e). It is the decision to invest the credit to purchase better quality of pesticides, herbicides, fertilisers, etc. The positive effect of the scheme (c) may be significant under conditions of farmers' education level improvement. Then, scheme (e) is a better investment for all farmers; either they have a high or low level of education. But the credit allocation to buy agricultural materials is positive only for the educated farmers; who are 53.53% of the surveyed farmers. The scores of efficiency are reduced by household size and gender of the household head. Therefore, households with less than 10 members, an educated man as head; are likely to improve their farms technical efficiency through two credit investments schemes: Credit×Capital and Credit×Intermediary-inputs. [less ▲]

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See detailDevelopment of alumina xerogel catalysts for biogas cleaning
Claude, Vincent ULg; Heinrichs, Benoît ULg; Toye, Dominique ULg et al

Poster (2014)

This poster resume the synthesis and characterizations of Ni/y-Al2O3 catalysts for the reforming of tars during the bio-syngas purification. The effect of an additionnal organosilane (EDAS) and a ... [more ▼]

This poster resume the synthesis and characterizations of Ni/y-Al2O3 catalysts for the reforming of tars during the bio-syngas purification. The effect of an additionnal organosilane (EDAS) and a surfactant (stearic acid) on the size,the dispersion and the sinterability of the nickel nanoparticles have been investigated. [less ▲]

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See detailMechanoreceptors in the anterior horn of the equine medial meniscus: an immunohistochemical approach.
Nemery, Elodie ULg; Gabriel, Annick ULg; Grulke, Sigrid ULg et al

Poster (2014)

Mechanoreceptors are “encapsulated sensory end-organs” involved in proprioceptive function. Given the high incidence of meniscal injuries in horses, the clinical interest in these mechanoreceptors ... [more ▼]

Mechanoreceptors are “encapsulated sensory end-organs” involved in proprioceptive function. Given the high incidence of meniscal injuries in horses, the clinical interest in these mechanoreceptors, particularly in the meniscus, and the lack of information concerning them in equine menisci, our objective was to study these corpuscles in the anterior horn of the equine medial meniscus, which is the most common localization reported for equine meniscal injuries. An immunohistochemical approach to detect Schwann cells and nerve fibres allowed us to localize and identify these corpuscles within the meniscus. Three types of mechanoreceptors were identified and localized between the abaxial quarter and the abaxial third of the meniscus: the Ruffini, Pacini and Golgi corpuscles. In conclusion, from a purely fundamental point of view, our work highlights for the first time the presence of MCR at the level of the anterior horn of the equine medial meniscus and proposes a classification based on specific immunocytochemical techniques. This morphological approach could serve as a basis for clinical studies, in order to evaluate the impact of these corpuscles on the poor sportive prognosis in equine meniscal tears. [less ▲]

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See detailMulti-scale model of the cardiovascular system
Kosta, Sarah ULg; Pironet, Antoine ULg; Negroni, Jorge et al

Poster (2014)

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See detailEfficient method for a controlled deposition of Pd nanoparticles on a glassy carbon electrode
Olu, Pierre-Yves; Chatenet, Marian; Job, Nathalie ULg

Poster (2014)

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See detailSteroid-like activity of migration products from non polycarbonate plastic baby bottles.
Simon, Coraline ULg; Onghena, Matthias; Covaci, Adrian et al

Poster (2014)

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See detailPréservation de la thymopïèse dans le grand âge
RICOUR, Céline ULg; de saint hubert, Marie; Martens, Henri ULg et al

Poster (2014)

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See detailEtude de la durabilité des hydrofuges de surface pour la conservation du patrimoine en béton
Lucquiaud, Vincent ULg; Courard, Luc ULg

Poster (2014)

La protection du patrimoine historique en béton est un challenge pour les années futures. Un traitement hydrofuge retarde l’apparition de pathologies du béton et apporte une protection contre la ... [more ▼]

La protection du patrimoine historique en béton est un challenge pour les années futures. Un traitement hydrofuge retarde l’apparition de pathologies du béton et apporte une protection contre la pénétration de l’eau. Les produits existants - essentiellement du silane et siloxane base - ont été soumis à différents processus de vieillissement, tels que la carbonatation accélérée, des rayons UV, des cycles d'humidification, des chocs thermiques, et des cycles de gel-dégel. Leur efficacité a été évaluée suivant la mesure de l’angle de contact, leur perméabilité à la vapeur d’eau et aux chlorures et leur absorption capillaire. Les résultats de l’étude montre un bon comportement de ces produits aux les principaux vieillissements étudiés. [less ▲]

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See detailNon-adiabatic study of the Kepler subgiant KIC 6442183
Grosjean, Mathieu ULg; Dupret, Marc-Antoine ULg; Belkacem, Kevin et al

Poster (2014)

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See detailMartian thermosphere scale height from SPICAM dayglow measurements
Stiepen, Arnaud ULg; Gérard, Jean-Claude; Bougher, Steve et al

Poster (2014)

We analyze the ultraviolet dayglow in the atmosphere of Mars through CO2+ and CO Cameron emissions. These emissions are accumulated on a large dataset of dayside grazing limb performed by the Spectroscopy ... [more ▼]

We analyze the ultraviolet dayglow in the atmosphere of Mars through CO2+ and CO Cameron emissions. These emissions are accumulated on a large dataset of dayside grazing limb performed by the Spectroscopy for Investigation of Characteristics of the Atmosphere of Mars (SPICAM) instrument on board the Mars Express spacecraft. The temperature of the Martian upper atmosphere can be retrieved from these limb emission profiles. We present discussion on the validity domain for such retrieval. We also show evidence for local (spatial and temporal) variability in the scale height of the atmosphere at the altitude of these emissions. [less ▲]

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See detailAcar'up, a new trapping device for house dust mites
Mailleux, Anne-Catherine; Deneubourg, Jean-Louis; Detrain, Claire et al

Poster (2014)

Detailed reference viewed: 22 (3 ULg)