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See detailMicroplastics contamination in two planktivorous and commercial fish species
Collard, France ULg; Parmentier, Eric ULg; Das, Krishna ULg

Poster (2014, May 13)

Plastic pollution is a huge environmental concern and affects each marine ecosystem. Plastics are produced by millions of tonnes each year in the world and finally accumulate in oceans. They adsorb many ... [more ▼]

Plastic pollution is a huge environmental concern and affects each marine ecosystem. Plastics are produced by millions of tonnes each year in the world and finally accumulate in oceans. They adsorb many persistent organic pollutants, cause external and internal wounds and provoke blockage of the digestive tract of marine mammals, birds and turtles. Plastics can also threaten marine organisms of small size class in the same way by fragmenting in smaller parts that result in microplastics of less than five millimetres. These microplastics are of the same order of magnitude than plankton and can thus be ingested by filter-feeders, suspension-filters and planktivorous organisms such as fish. Few studies deal with microplastics ingestion by fish and even less by commercial fish species. The herring (Clupea harengus) and the sardine (Sardina pilchardus) were respectively the third and the eighth most caught fish species in the world in 2009. We focused our research on these two species which are of economic importance. We sampled around thirty individuals of each species in the Channel and in the North Sea in January 2013. The stomach contents were digested by sodium hypochlorite and then analyzed. Microplastics were characterized by size, colour and shape. The results of these analyses will highlight the need for studies about microplastics ingestion by planktivorous species. [less ▲]

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See detailSupercritical CO2 and polycarbonate based nanocomposites: A critical issue for foaming
Monnereau, Laure; Urbanczyk, Laetitia; Thomassin, Jean-Michel ULg et al

in Polymer (2014), 55(10), 2422-2431

Supercritical carbon dioxide readily induced foaming of various polymers. In that context, supercritical CO2 was applied to carbon nanotubes based polycarbonate nanocomposites to ensure their foaming ... [more ▼]

Supercritical carbon dioxide readily induced foaming of various polymers. In that context, supercritical CO2 was applied to carbon nanotubes based polycarbonate nanocomposites to ensure their foaming. Surprisingly, efficient foaming only occurs when low pressure is applied while at high pressure, no expansion of the samples was observed. This is related to the ability of supercritical carbon dioxide to induce crystallization of amorphous polycarbonate. Moreover, this behaviour is amplified by the presence of carbon nanotubes that act as nucleating agents for crystals birth. The thermal behaviour of the composites was analysed by DSC and DMA and was related to the foaming observations. The uniformity of the cellular structure was analysed by scanning electron microscopy (SEM). By saturating the polycarbonate nanocomposites reinforced with 1 wt% of MWNTs at 100 bar and 100 °C during 16 h, microcellular foams were generated, with a density of 0.62, a cell size ranging from 0.6 to 4 μm, and a cellular density of 4.1 × 1011 cells cm−3. The high ability of these polymeric foams to absorb electromagnetic radiation was demonstrated at low MWNT content as the result of the high affinity of the polycarbonate matrix for MWNTs, and therefore to the good MWNTs dispersion. [less ▲]

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See detailLinear amphiphilic diblock copolymers of lactide and 2-dimethylaminoethyl methacrylate using bifunctional-initiator and one-pot approaches
Kryuchkov, Maksym A.; Detrembleur, Christophe ULg; Bazuin, Géraldine

in Polymer (2014), 55(10), 2316-2324

Linear amphiphilic diblock copolymers of polylactide (PLA) and poly(2-dimethylaminoethyl methacrylate) (PDMAEMA) were synthesized by atom transfer radical polymerization (ATRP) of DMAEMA followed by ring ... [more ▼]

Linear amphiphilic diblock copolymers of polylactide (PLA) and poly(2-dimethylaminoethyl methacrylate) (PDMAEMA) were synthesized by atom transfer radical polymerization (ATRP) of DMAEMA followed by ring-opening polymerization (ROP) of LLA using the bifunctional initiator, 2′-hydroxyethyl 2-bromoisobutyrate. NMR showed that the resulting PLA block was racemic and a quaternization/precipitation technique showed that there were significant amounts of racemic PLA homopolymer. In addition, simultaneous ATRP of DMAEMA and ROP of l-lactide by tin octoate were conducted at varied temperatures, indicating 90 °C as a suitable compromise temperature; this one-pot process also led to racemization and P(L)LA homopolymer. The racemization was attributed to reversible deprotonation of LLA by the N(CH3)2 moiety of (P)DMAEMA and the PLA homopolymer impurity was related to in situ formation of lactoyl lactate (LA–LA) due to nucleophilic ring opening of lactide by the amino moieties of (P)DMAEMA. The methods presented can be useful for the preparation of PDMAEMA–b–PLA/PLA composites in a two-step process or in a single step, one-pot process. [less ▲]

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See detailImpact de la réduction des armes nucléaires américaines en Europe
Dumoulin, André ULg

Scientific conference (2014, May 13)

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See detailRevascularisation en cas d’artériopathie périphérique du membre inférieur – Résumé.
Vlayen, Joan; Holdt Henningsen, Kirsten; d’Archambeau, Olivier, Olivier et al

Report (2014)

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See detailFully implicit integration scheme for the GTN model
Guzmán Inostroza, Carlos Felipe ULg; Habraken, Anne ULg

Poster (2014, May 12)

Fully integration scheme for the GTN model, applied to some shear extensions. The model also comprises Hill type anisotropy and mixed (Isotropic/kinematic) hardening. The consistent tangent matrix is also ... [more ▼]

Fully integration scheme for the GTN model, applied to some shear extensions. The model also comprises Hill type anisotropy and mixed (Isotropic/kinematic) hardening. The consistent tangent matrix is also calculated. [less ▲]

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See detailTrace element bioaccumulation in rope-grown Mytilus galloprovincialis: knowledge update
Richir, Jonathan ULg; Gobert, Sylvie ULg

Poster (2014, May 12)

Numerous trace elements (TEs) can be considered as potential pollutants of the environment, their mining productions and industrial uses increasing worldwide. Their monitoring can be achieved through the ... [more ▼]

Numerous trace elements (TEs) can be considered as potential pollutants of the environment, their mining productions and industrial uses increasing worldwide. Their monitoring can be achieved through the use of bioindicator species, such as the Mediterranean mussel Mytilus galloprovincialis (Lamarck, 1819). That species has been widely used to monitor the chemical pollution of coastal ecosystems by Cr, Ni, Cu, Zn, Cd, Pb, As, Ag and V. Conversely, environmental levels of Be, Al, Fe, Mn, Co, Se, Mo, Sn, Sb and Bi have been little or not monitored so far in mussel watch programs. Bioaccumulation processes of these 19 TEs in rope-grown M. galloprovincialis purchased from a salt pond with good chemical water quality were thus investigated in the present study. Mussels efficiently accumulated the 19 studied TEs. Bioaccumulation processes were driven by numerous mutually dependent biological parameters such as the mussel size and flesh weight, the sex and the reproductive status and the body compartment considered. TE bioaccumulation was a power function of the mussel soft body dry weight; total contents linearly increased with the shell length. Small-size mussels overall concentrated more TEs, with a high interindividual variability, consequently influencing the modelling of their bioaccumulation in the whole rope population. Although a large range of rope-grown M. galloprovincialis sizes can be used for monitoring purposes, one will thus take care not to use extreme size individuals. The influence of gametogenesis in determining female body higher TE concentrations prior to spawning could not be neglected and varied depending on the element. TEs were preferentially accumulated in the hepatopancreas, except for Zn, Se, Cd and Mo, more concentrated in gills. Gametogenesis did not influence TE distribution between body compartments, but likely diluted their concentrations as a direct consequence of massive reproductive tissue production. So, results from the present study underlined the potential use of M. galloprovincialis in the biomonitoring of numerous little studied TEs and gave some insights into the decisive role played by some relevant biological parameters in bioaccumulation processes of the 19 investigated TEs in rope-grown mussels. [less ▲]

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See detailAn Ant Colony System for Responsive Dynamic Vehicle Routing
Schyns, Michael ULg

E-print/Working paper (2014)

We present an algorithm based on an Ant Colony System to deal with a broad range of Dynamic Capacitated Vehicle Routing Problems with Time Windows, (partial) Split Delivery and Heterogeneous fleets ... [more ▼]

We present an algorithm based on an Ant Colony System to deal with a broad range of Dynamic Capacitated Vehicle Routing Problems with Time Windows, (partial) Split Delivery and Heterogeneous fleets (DVRPTWSD). Besides the traditional distance criterion, we address the important case of responsiveness. Responsiveness is defined here as completing a delivery as soon as possible, within the time window, such that the client or the truck may restart its activities. This is crucial for many production or service activities in different fields: express parcel deliveries, taxi services, Just in Time production, express repair services, medical care, petrol station replenishment, etc. We develop an interactive web-based solution to allow dispatchers to take new information into account in real-time. The algorithm and its parametrization were tested on real and artificial instances. We first illustrate our approach with a problem submitted by Liege Airport, the 8th biggest cargo airport in Europe. The goal is to develop a decision system to optimize the journey of the refueling trucks. We then consider some classical VRP benchmarks with extensions for more complex problems. [less ▲]

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See detailModeling using the SWAT model of water flow and transport in suspension in the watershed of the valley of Wadi El-Hachem
Tadrist, Nassima ULg; DEBAUCHE, OLIVIER ULg; Degré, Aurore ULg et al

Poster (2014, May 12)

In the Maghreb, dams regularly suffer from excessive siltation due to erosion problems present in the catchment areas. The origins of this erosion are multiple: land use, deforestation, land affectation ... [more ▼]

In the Maghreb, dams regularly suffer from excessive siltation due to erosion problems present in the catchment areas. The origins of this erosion are multiple: land use, deforestation, land affectation , ... Hydrology coupled with geographic information systems allows using distributed and physically based models to predict the evolution of siltation of dams. The application of these models in Algeria will finally predict the impact of anti-erosion measures, land use patterns on the siltation of dams accurately estimating the amount of sediment produced by erosion runoff and the degree of filling. A methodology based on the map data (digital terrain model, map soil science, geology map and mapping of land use) and daily meteorological data (temperature, relative humidity, wind speed, solar radiation) is being development and testing of the dam Bourkourdane. The SWAT model is used to predict the amount of sediment accumulating in the dam, the water flow rate inbound, outbound, and the volumes of water and sediment stored in the dam. Adequate management of releases, coupled with better management of erosion upstream of the dam will extend the life of dams Algerians. Especially for Boukourdane, improved management of releases is paramount to improve groundwater recharge, fight against the intrusion of marine waters and prevent the accumulation of fine particles that reduce soil permeability. [less ▲]

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See detailThe small Heat Shock Proteins (sHSPs) response following eccentric exercise
Hody, Stéphanie ULg

Conference (2014, May 12)

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See detailModeling of a glass mineral wool process in view of Life Cycle Analysis
Gerbinet, Saïcha ULg; Léonard, Angélique ULg; Briard, Vincent

Poster (2014, May 12)

In line with the growing concern about the environmental impact of materials in the building sector, Knauf Insulation, a glass wool producer, is performing environmental impact assessment of its products ... [more ▼]

In line with the growing concern about the environmental impact of materials in the building sector, Knauf Insulation, a glass wool producer, is performing environmental impact assessment of its products through LCA. Knauf Insulation has several glass wool factories in Europe that produce various products, and for a specific market, the same product can be produced in several factories. As the plants that produce glass wool work with similar pathways, a generic model for LCA usable for every plant and every glass wool product has been designed. Moreover, combination of different factories is also possible. The general principle of glass wool production is the following: the raw materials, sand, limestone, soda ash, borax, sodium carbonate, as well as recycled off-cuts from the production process, are weighed and mixed. Knauf Insulation also uses a large amount of recycled glass (cullet). The mix is sent to a furnace at high temperature (1350°C). The melted material is then fiberized and the binder is added, a process called forming. Knauf Insulation uses a special binder with ECOSE Technology, a new and formaldehyde-free binder. The wool fibers are collected, by suction, on a conveyor belt, and the mattress then goes through the curing oven. For some product a facing is added. Finally the product is compressed and packed. The model, implemented in GaBi 6, is made as generic as possible by including, for each step, all the raw materials that can be used in one of the factories as well as all the energy sources. Parameters allow to define the amount of each raw material consumed, therefore the model can be adapted to any factory simply by setting these parameters accordingly. This also simplifies the data collection, since the template is the same for all the factories, it can be supported by data collection tools already existing. A part of the model is dedicated to weighting between factories, so a combination of factories can also be studied. The model can also be adapted to almost all Knauf Insulation products by using parameters where necessary: for example, several products have different binder contents, so a parameter defines the amount of binder. As some materials can be recycled between several parts of the process, special attention has been paid to recycling loops inside the model. The model is flexible enough to be used for Environmental Product Declaration (EPD) as well as for Eco-Design purposes. [less ▲]

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See detailFrom Sputnik to Beanie Babies & CubeSats to OUFTI
Verly, Jacques ULg

Conference given outside the academic context (2014)

Detailed reference viewed: 11 (3 ULg)
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See detailConcept et agencement de la lutte contre la "fraude sociale"
Kéfer, Fabienne ULg

in Vermeulen, Geert; Masset, Adrien; Flore, Daniel (Eds.) Comment s'en prendre à la fraude sociale, l'exploitation au travail et la traite des êtres humains : défis et solutions aux niveaux national et européen (2014, May 11)

Detailed reference viewed: 16 (1 ULg)
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See detailA clinical lab experience with an automated HIV Antigen/Antibody (Ag/Ab) combined assay
HUYNEN, Pascale ULg; TOUSSAINT, Françoise ULg; GERARD, Christiane ULg et al

Poster (2014, May 11)

OBJECTIVES: To describe the diagnostic performance of a new fourth-generation HIV Ag/Ab chemiluminescent immunoassay, available on the new LIAISON® XL analyser, in a clinical setting. METHODS: Through ... [more ▼]

OBJECTIVES: To describe the diagnostic performance of a new fourth-generation HIV Ag/Ab chemiluminescent immunoassay, available on the new LIAISON® XL analyser, in a clinical setting. METHODS: Through February 2012-October 2013, 12,438 samples of serum, received at our laboratory for screening for HIV infection were routinely tested with LIAISON® XL Murex HIV Ab/Ag assay (HIV-XL), which employs HIV-1, HIV-1 group O, and HIV-2 antigens and anti-p24 monoclonal antibodies in two coupled reagent cartridges, providing information of the overall Ab/Ag reactivity and detail of the specific reactivity for anti-HIV/HIV p24 antigen. Each serum with positive result or with negative result displaying a value close to the cut-off were sent to the regional AIDS-Reference Laboratory (RefLab) to perform confirmatory assays (PCR, Immunoblot). A previous verification of the HIV-XL demonstrated 100% sensitivity with a challenge panel of hundred positive sera provided by the RefLab. Performed external quality control was from United-Kingdom National External Quality Assessment Service (NEQAS). RESULTS: Out of the clinical samples, 12,312 non-reactive samples (including 6 negative results displaying a value close to the cut-off further confirmed true HIV negative), 64 Ab HIV reactive samples (all confirmed HIV-1 positive by immunoblot), including 4 samples reactive also for Ag HIV (confirmed positive by Ag assay/PCR), 42 Ab HIV reactive samples tested negative by immunoblot, and 20 Ag HIV reactive samples tested negative by the kit used for the Ag p24 detection in our HIV Reference Lab, have been found. All the 43 NEQAS specimens tested, 16 reactive and 27 non-reactive, were correctly classified. These results, considered all together, provide a calculated positive predictive value of 57.5% with an estimated specificity of 99.5% (with 95% confidence interval of 99.36-99.62%), and a calculated negative predictive value of 100% with an estimated sensitivity of 100.0% (with 95% confidence interval of 95.49-100%). CONCLUSIONS: In our experience HIV-XL showed excellent performance associated to all the advantages of a fully automated/random access instrument. [less ▲]

Detailed reference viewed: 40 (15 ULg)