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See detailStudy of durability and the physico-mechanical properties of thermally modified wood
Ninane, Maxime; Jourez, Benoît ULg; Hebert, Jacques ULg

Poster (2015, January 30)

Heat-treated wood is a credible alternative for certain kinds of tropical timber. It is also an alternative for certain polluting wood preservatives. This study aims to determine the changes in physico ... [more ▼]

Heat-treated wood is a credible alternative for certain kinds of tropical timber. It is also an alternative for certain polluting wood preservatives. This study aims to determine the changes in physico-mechanical properties and durability of wood that is subjected to heat treatment. For this, we studied five species (oak, ash, natural beech and a variant known as steamed beech, poplar, Douglas-fir). For each species, we had fifteen reference samples and fifteen corresponding treated samples. The results show a decrease in the hygroscopicity and an increase in dimensional stability of heat-treated wood in relation to the degradation of hemicelluloses. The mechanical properties are influence variously, because heat-treated wood is stiffer but also more brittle. The modulus of elasticity increases slightly after treatment. Side hardness and compressive fracture of heat-treated wood may increase up to 30%. On the other hand, the modulus of rupture, the ability to slit and impact may decrease by 50%, 60% and 70%. The durability of heat-treated wood against wood-destroying fungi increases. However, within each species, the durability increase varies greatly. Additional tests conducted to understand this variability, suggests that the heat distribution is not homogeneous within the processing unit. Moreover, our work suggests that durability is related to the fixed carbon content and that this path would be interesting to explore in the future. [less ▲]

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See detailElicitation of the defence mechanisms at plant case of Cucumis melo
Ydjedd, Siham; Kati, D.E.; Fauconnier, Marie-Laure ULg

Poster (2015, January 30)

The judicious use of elicitors could reduce the amount of pesticide necessary to protect crops and preservation of the environment. This strategy frequently called "stimulation of natural defenses ... [more ▼]

The judicious use of elicitors could reduce the amount of pesticide necessary to protect crops and preservation of the environment. This strategy frequently called "stimulation of natural defenses" arouses more and more interest in the phytosanitary field. [less ▲]

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See detailInteractions of natural rhamnolpids produced by Pseudomonas aeruginosa with plant model membranes
Polo Lozano, Damien ULg; Nasir, Mehmet Nail ULg; Deleu, Magali ULg et al

Poster (2015, January 30)

It is well known that chemical pesticides have harmful effects on human health and environment. In this context, the interest for alternative products such as biopesticides is increasing. Among them ... [more ▼]

It is well known that chemical pesticides have harmful effects on human health and environment. In this context, the interest for alternative products such as biopesticides is increasing. Among them, elicitors act on the plants by inducing systemic resistance against diseases caused by fungal, viral, bacterial agents and insects. Rhamnolipids are surface active molecules produced mainly by various strains of the bacterium Pseudomonas aeruginosa. These secondary metabolites are composed of one to three fatty acids with various chain lengths linked through a glycosidic bond to one or two rhamnose moieties. The fatty acids are linked together through an ester bond. These molecules have shown several biological activities including plant defense stimulation. It has been suggested that this elicitor activity could be related to an interaction of rhamnolipids with the lipid bilayer of the plant plasma membrane (PPM) and lead to its destabilization, which can activate the plant defense signaling pathways. In this context, interactions of two rhamnolipids (Rha-C10-C10 and Rha-Rha-C10-C10) with biomimetic membranes of PPM such as Langmuir monolayers and multilayers were investigated using biophysical and in silico approaches. [less ▲]

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See detailL'expérience d'une vie : Sartre, Fanon et nous
Cormann, Grégory ULg

Conference given outside the academic context (2015)

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See detailStructural, functional, and ACE inhibitory properties of water-solublepolysaccharides from chickpea flours
Mokni Ghribi, abir; Sila, Assaâd; Maklouf Gafsi, Ines et al

in International Journal of Biological Macromolecules (2015), 75

tThe present study aimed to characterize and investigate the functional and angiotensin-I convertingenzyme (ACE) inhibition activities of chickpea water-soluble polysaccharides (CPWSP). Physico ... [more ▼]

tThe present study aimed to characterize and investigate the functional and angiotensin-I convertingenzyme (ACE) inhibition activities of chickpea water-soluble polysaccharides (CPWSP). Physico-chemicalcharacteristics were determined by nuclear magnetic resonance spectroscopy (NMR), Fourier transform-infrared spectroscopy (FT-IR) analysis, and X-ray diffractometry (XRD). Functional properties (waterholding capacity: WHC, water solubility index: WSI, swelling capacity: SC, oil holding capacity: OHC,foaming, and emulsion properties) and ACE activities were also investigated using well-established pro-cedures. The FT-IR spectra obtained for the CPWSP revealed two significant peaks, at about 3500 and500 cm−1, which corresponded to the carbohydrate region and were characteristic of polysaccharides.All spectra showed the presence of a broad absorption between 1500 and 670 cm−1, which could beattributed to C−H, C−O, and O−H bands in the polysaccharides. CPWSP had an XRD pattern that wastypical for a semi-crystalline polymer with a major crystalline reflection at 19.6◦C. They also displayedimportant techno-functional properties (SWC, WSI, WHC, and OHC) that can be modulated accordingto temperature. The CPWSP were also noted to display good anti-hypertensive activities. Overall, theresults indicate that CPWSP have attractive chemical, biological, and functional properties that makethem potential promising candidates for application as alternative additives in various food, cosmetic,and pharmaceutical preparations. [less ▲]

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See detailL'arme de la transition énergétique pour combattre les djihadistes
Ernst, Damien ULg; Hermans, Michel ULg

Article for general public (2015)

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See detailBiochemical methane potential of residues of three banana varieties from Cameroon : fresh and dry peduncles
Awedem wobiwo, Florent; Happi Emaga, Thomas; Fokou, Elie et al

Poster (2015, January 30)

In Cameroon , the ratio of energy cost to standard of living for both electric and fuel energy is higher than in USA and EU. The local energy needs could be met by valorizing local wastes in an ... [more ▼]

In Cameroon , the ratio of energy cost to standard of living for both electric and fuel energy is higher than in USA and EU. The local energy needs could be met by valorizing local wastes in an environmentally and economically sustainable way. Banana and plantain plants produce significant quantities of post-harvest biomass wastes such as bulbs, pseudo stems, leaf sheaths, petioles–midribs, leaf blades, peduncles, rachis and blossoms which can be converted to methane-rich biogas by anaerobic digestion (AD). AD is a natural process of degradation of organic materials. [less ▲]

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See detailLangmuir film balance- A technique to study the interaction of β-cyclodextrin with cholesterol in milk fat globule membrane monolayers
Malik, Priyanka ULg; Danthine, Sabine ULg; Paul, Aman ULg et al

Poster (2015, January 30)

Milk is a natural complex system present as oil in water emulsion. The natural organisation of milk fat globules is stabilized by the presence of a natural membrane, called the milk fat globule membrane ... [more ▼]

Milk is a natural complex system present as oil in water emulsion. The natural organisation of milk fat globules is stabilized by the presence of a natural membrane, called the milk fat globule membrane (MFGM). It has tripartite structure consisting of a monolayer facing the inner triacylglycerol core and an external bilayer. This MFGM accounts for 2-6% of fat globule. The MFGM is composed of both polar lipids and proteins. Cholesterol is also present in MFGM and accounts for about 2% of MFGM. Langmuir film balance is a technique to study monolayers and is a useful tool to examine the effect of cholesterol removal on surface properties of MFGM. β-cyclodextrin has no surface activity of its own and is thus a useful tool to study the effect of cholesterol desorption on surface properties in membrane. The removal of monolayer cholesterol to the sub-phase is proportional to the area decrease of the monolayer at a constant surface pressure. Amount of cholesterol removed can also be calculated as a function of mean molecular area at a given pressure, time and temperature. Using the monolayer technique, it is possible to study the interactions between β-cyclodextrin and MFGM film as well as effect of cholesterol removal in altering the surface properties MFGM. [less ▲]

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See detailUtility of removing cholesterol from an industrial by-product- Buttermilk powder
Malik, Priyanka ULg; Danthine, Sabine ULg; Paul, Aman ULg et al

Poster (2015, January 30)

Almost 16% of milk produced in European Union is being converted to butter. Buttermilk, is a low cost by-product from butter manufacture and available in large quantities but has been considered ... [more ▼]

Almost 16% of milk produced in European Union is being converted to butter. Buttermilk, is a low cost by-product from butter manufacture and available in large quantities but has been considered invaluable for many years. When cream is churned to butter the stable oil in water emulsion is destabilized and milk fat globule membrane (MFGM) is disrupted which is released in buttermilk. Thus, over the last two decades it has gained considerable attention due to its specific composition (proteins and polar lipids) attributed towards the MFGM. In account to this composition of buttermilk powder, it finds application in food industry as a natural stabilizing and emulsifying agent. It also finds application as a source of total solids and is commercially being added upto 10% in many food products. However, it has limitation in such applications due to the presence of cholesterol (approx. 80mg/100g). Cholesterol is also an integral part of MFGM and is released into buttermilk with MFGM. The most suitable techniques to remove cholesterol from buttermilk powder are using β-cyclodextrin and cholesterol oxidase enzyme. To valorize this abundantly produced industrial by-product of butter industry and increase its application in health food industry, as well as extend its application in pharmaceutical industry and preparation of liposomes, it is important to remove cholesterol from buttermilk. [less ▲]

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See detailNitrous oxide flux measurement with a closed chamber system : data treatment
Regaert, Donat ULg; Moureaux, Christine ULg; Heinesch, Bernard ULg et al

Poster (2015, January 30)

Nitrous oxide flux estimation from concentration measurements with a closed chamber system. Statistical data treatment to sort between relevant/irrelevant fluxes.

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See detailWildflower strips for crop protection: What do we know ? What should we know ?
Hatt, Séverin ULg; Uyttenbroeck, Roel ULg; Bodson, Bernard ULg et al

Poster (2015, January 30)

Wildflower strips (WFS) are known to support the conservation of a large diversity of insects and thus natural enemies (i.e. predators and parasitoids) that can control pests. However, the conclusions of ... [more ▼]

Wildflower strips (WFS) are known to support the conservation of a large diversity of insects and thus natural enemies (i.e. predators and parasitoids) that can control pests. However, the conclusions of studies looking at the efficiency of WFS to control pests are not unanimous. Indeed, the enhancement of pest control seems to depend on (1) the ability of flowers to attract the natural enemies at the right moment and (2) the capacity of natural enemies to migrate into the adjacent crops to attack pests. Therefore, constituting appropriate flower mixes may be an essential lever to enhance the efficiency of pest control. In this context, using functional diversity is promising. To our knowledge, few studies have tested the impact of the functional diversity of a flower mix on insect abundance and diversity and the control of pests. Through this contribution, the insect diversity and abundance found to be associated with the different kinds of WFS and management applied will be discussed, as well as the further research needed. [less ▲]

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See detailLinking bees and flowers: mutualistic interaction networks to study ecosystem functioning
Uyttenbroeck, Roel ULg; Monty, Arnaud ULg

Poster (2015, January 30)

In recent years, much attention is going to pollinators, as they are important for the increasing food production while being threatened by agricultural intensification and other environmental drivers ... [more ▼]

In recent years, much attention is going to pollinators, as they are important for the increasing food production while being threatened by agricultural intensification and other environmental drivers. While honeybees (Apis mellifera L.) are generalist according to their flower preferences, wild pollinators’ flower preferences can go from generalist to very specialist. The same goes for plant species, which can be generalist or specialist in the pollinator species they need to get pollinated. The combination of a set of generalist and specialist plant species with a pollinator community consisting of generalists and specialists in a certain habitat, results in an interaction network between pollinators and the visited plant flowers. Studying this mutualistic interaction network is a time-consuming method, but can provide valuable data to calculate indicators of ecosystem functioning. One of the important conclusions that came already out of studies applying this method is that pollination systems are often more generalized than thought based on pollination syndromes. This poster will explore the method of studying mutualistic interaction networks with a focus on the sampling protocol, the indicators that can be derived from the data and their meaning. [less ▲]

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See detailLessons from the field: Negotiating Transnational Gender, Class and Race Positions as a Researcher Working on Andean Domestic Workers in Brussels
Vivas Romero, Maria ULg

Scientific conference (2015, January 30)

This paper shows the links between migrant transnationalism and the methodological debates concerning the researcher’s positionality and self-reflexivity, which have not been systematically considered in ... [more ▼]

This paper shows the links between migrant transnationalism and the methodological debates concerning the researcher’s positionality and self-reflexivity, which have not been systematically considered in transnational studies. Drawing from my experiences as a transnational female migrant conducting fieldwork among Andean domestic workers in the city of Brussels; I intent to contribute to the conceptualization of positionality by reflecting on the effect of the researcher’s transnational gender, class and race positions in qualitative migration research. Firstly, I address the conflicts that arose from my positioning as an “insider” that initially granted me a social proximity with my participants but later raised awareness on the existent social boundaries between us and temporarily blocked my access to the field. Secondly, I will highlight the methodological strategies through, which I worked around the existent boundaries of power relations and eventually gained access to the field, meaning: A- Constantly, engaging in self-reflexivity and questioning my “insider/outsider positioning, B- Consciously and unconsciously negotiating my class, gender and race positioning’s in order to re-draw the boundaries in the relationship between the participants and the researcher, C- Relying on my experiences as a transnational migrant in order to grasp the meaning of their practices, which guided me to avoid my spontaneous interpretations and reconsider those that my participants gave me . Finally, I will argue that both mobilizing one’s personal background and negotiating our intersecting transnational positionalities during fieldwork constitute valuable methodological resources that might lead us to do research that is produced through more symmetrical power relations. [less ▲]

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See detailEvaluation et gamification - Transformer un quiz de chimie en un mini-jeu
le Maire, Nathalie ULg; Fauconnier, Marie-Laure ULg; Colaux, Catherine ULg et al

Conference (2015, January 30)

Le recours à des questionnaires à choix multiples pour l’évaluation des étudiants est une pratique courante à l’université. Cette communication décrit et analyse une expérimentation contrôlée visant à ... [more ▼]

Le recours à des questionnaires à choix multiples pour l’évaluation des étudiants est une pratique courante à l’université. Cette communication décrit et analyse une expérimentation contrôlée visant à explorer les effets de la présentation d’un QCM formatif sous la forme d’un jeu. L’étude s’inscrit ainsi dans les recherches actuelles sur les avantages et les limites pédagogiques de la « gamification », à savoir la transposition des principes issus de l’univers du jeu au domaine de l’éducation (Johnson, Adams Becker, Estrada, & Freeman, 2014). La présente recherche est effectuée dans le cadre d’un doctorat dédié spécifiquement à la gamification d’évaluations formatives. L’étude repose sur la mise à disposition de plusieurs versions d’un quiz portant sur un chapitre d’un cours de chimie générale en première année d’université. Le dispositif expérimental prévoit un enrichissement graduel de la gamification selon quatre prototypes conçus après identification et extraction de schèmes visant à stimuler et maintenir la motivation et la performance dans des jeux actuels et populaires tels que Candy Crush, Angry Birds ou Hay Day. Située à l’entrée du doctorat, cette étude vise, outre la collecte de données quant à l’utilisabilité du mini-jeu proposé, à mettre en lumière ses effets sur l’état de flow dans le contexte des edugames et contribuera à la validation de la traduction française de l’échelle d’EGameFlow (Fu, Su, & Yu, 2009). [less ▲]

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See detailInfluence of cover crop management on sugar beet production
Hiel, Marie-Pierre ULg; Bodson, Bernard ULg

Poster (2015, January 30)

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See detailActivation of the calcium-sensing receptor before renal ischemia/reperfusion exacerbates kidney injury
WEEKERS, Laurent ULg; De Tullio, Pascal ULg; BOVY, Christophe ULg et al

in American Journal of Translational Research (2015), 7(1), 128-138

Activation of the calcium-sensing receptor (CaSR) by ischemia/reperfusion (I/R) favours apoptosis in cardiomyocytes, hepatocytes and neurons. Its role in renal I/R is unknown. We investigated the impact ... [more ▼]

Activation of the calcium-sensing receptor (CaSR) by ischemia/reperfusion (I/R) favours apoptosis in cardiomyocytes, hepatocytes and neurons. Its role in renal I/R is unknown. We investigated the impact of pharmacological preactivation of the CaSR on kidney structure and function in a murine model of bilateral renal 30-min ischemia and 48-hour reperfusion, and in a 6-year cohort of kidney transplant recipients (KTR). C57BL/6J mice were administered daily with CaSR agonist, R-568, or with vehicle for 48 hours. Evaluation of serum urea and creatinine levels, renal histology and urine metabolome by nuclear magnetic resonance showed that R-568 was not nephrotoxic per se. Following I/R, serum urea and creatinine levels increased higher in R-568-treated animals than in controls. Jablonski’s score was significantly greater in R-568-treated kidneys, which showed a higher rate of cell proliferation and apoptosis in comparison to controls. Next, we retrospectively identified 36 patients (10.7% of our cohort) who were treated by CaSR agonist, cinacalcet, at the time of kidney transplantation (KTx). After matching these to 61 KTR upon type of donor, cold ischemic time, residual diuresis, and donor age, we observed that delayed graft function, i.e. need for dialysis in the first week after KTx, occurred in 42 and 23% of cinacalcet-treated and control groups, respectively (p≤0.05). These data suggest that pharmacological preactivation of the CaSR before renal I/R exacerbates kidney injury. [less ▲]

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See detailInvestigating the Effects of Plant Root Exudates on PAHs Bioavailability to Soil Microorganisms in Contaminated Brownfields : Research Methodology.
Davin, Marie ULg; Lognay, Georges ULg; Fauconnier, Marie-Laure ULg et al

Poster (2015, January 30)

As a result of heavy industrial past activities, an estimated 6,000 brownfields require remediation in Wallonia. This number rises to over 3.5 million in Europe. Polycyclic Aromatic Hydrocarbons (PAHs ... [more ▼]

As a result of heavy industrial past activities, an estimated 6,000 brownfields require remediation in Wallonia. This number rises to over 3.5 million in Europe. Polycyclic Aromatic Hydrocarbons (PAHs) represent 17% of treated pollutants in Wallonia (Aldric et al., 2011). Current remediation techniques are rather expensive and technically demanding (Megharaj et al., 2011). Based on the observation that PAHs soil content decreases in the presence of plants (Cheema et al., 2010), the PhD aims at developing alternative PAHs remediation techniques in brownfields. It is articulated around three research axes. The first axis focusses on plant exudates and how they may improve PAHs bioavailability to soil microorganisms and enhance their degradation. This will be investigated by (i) characterizing several contaminated soils (physico-chemical parameters) and PAH content and factors of bioavailability, (ii) selecting a plant model and collecting root exudates, and (iii) evaluating the effects of exudates on PAHs bioavailability. The objective of the second axis is to evaluate the effects of plant exudates on PAHs degrading microorganisms by (i) comparing PAHs biodegradation in the presence/absence of exudates and (ii) assessing the potential toxic effects of exudate compounds on the microbial communities. The aim of the third axis is to study plant-pollutants interactions by (i) establishing the plant tolerance to several contamination levels and (ii) following PAHs bioavailability when facing real exudation rates, on the field. [less ▲]

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See detailLa participation : pour quoi faire ?
Mormont, Marc ULg

Conference given outside the academic context (2015)

La participation du public aux politiques environnementales peut prendre de multiples formes. Mais elle relève aussi de justifications différentes qui correspondent à des formes d'engagement très ... [more ▼]

La participation du public aux politiques environnementales peut prendre de multiples formes. Mais elle relève aussi de justifications différentes qui correspondent à des formes d'engagement très différentes. La contribution de la participation est légitime au plan légal et politique, mais son instrumentation est faible. L'auteur insiste sur deux critères cruciaux d'évaluation ; la délibération et les niveaux d'engagement des publics. [less ▲]

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