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See detailIdentification de sous-groupes de glioblastome sur base de critères cliniques
Lambert, Jérémy ULg; Scholtes, Félix ULg; MARTIN, Didier ULg

Poster (2014, December)

Glioblastoma has terrible outcomes, but the disease evolution varies a lot between patients. We used a sample of 239 patients (EORTC 26981) and a validation sample of 93 patients (CHU Liège) to class ... [more ▼]

Glioblastoma has terrible outcomes, but the disease evolution varies a lot between patients. We used a sample of 239 patients (EORTC 26981) and a validation sample of 93 patients (CHU Liège) to class patients in groups with the same risk of recurrence. 4 distinct subgroups were created using recursive partitioning analysis. In the future, genetic profile will be compared between these groups to find markers of aggressiveness. Moreover, survival after recurrence is closely related to subgroups, and a surgical resection of the recurrence shows positive effect in each subgroup. [less ▲]

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See detailPoster session 5: Friday 5 December 2014, 14:00-18:00Location: Poster area.
Henri, C.; DULGHERU, Raluca Elena ULg; Magne, J. et al

Poster (2014, December)

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See detailMRI myocardial perfusion, a reliable alternative to FFR
GHEKIERE, Olivier; DEWILDE, W; HOA, D et al

Poster (2014, December)

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See detailLate-Holocene moist forests of Central Africa: contribution of charcoal analysis
Morin, Julie ULg; Bremond, Laurent; Gillet, Jean-François et al

Poster (2014, December)

Wood charcoals are often uncovered in the soils of the tropical regions. They remain little studied, however, and this observation is even truer for charcoals coming from the dense humid forests of ... [more ▼]

Wood charcoals are often uncovered in the soils of the tropical regions. They remain little studied, however, and this observation is even truer for charcoals coming from the dense humid forests of Central Africa. Here we aim at showing the interest of the analysis of soil charcoals in this region so as to understand the dynamics of past forest environments during the late-Holocene. Several examples of taxonomical identifications conducted on charcoals sampled in soil pits in Cameroon and in the Republic of the Congo are presented along with radiocarbon dates. These charcoals were hand-split then observed under an incident light microscope. The wood anatomical features that were preserved in charcoals and described according to a standard method were compared to a reference collection of woods. Results demonstrated that past burnings that spanned from 2,500 BP to Recent were human-induced and scattered in the study area. The identified species are still present in the environment today and localized changes in the vegetation occurred over the past two millennia. Charcoal analysis can thus allow a better understanding of the past history of the tropical forests in relationship with the ancient anthropogenic disturbances. [less ▲]

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See detailIN UTERO INFECTION BY SCHMALLENBERG VIRUS INDUCES ARTHROGRYPOSIS MULTIPLEXA CONGENITA IN OVINE FETUSES
Boseret, Geraldine; Claine, Francoise; Coupeau, Damien et al

Poster (2014, December)

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See detailThe influence of bioavailable copper and zinc concentrations on metallothionein levels, DNA damage and gene expression in the polychaete Nereis (Alitta) virens (M. Sars, 1835)
Pini, Jennifer; Richir, Jonathan ULg; Watson, Gordon

Poster (2014, December)

Nereis (Alitta) virens is an ecologically and commercially important polychaete of intertidal soft sediment and an ideal species to investigate long term effects of metals. Using a spike approach, worms ... [more ▼]

Nereis (Alitta) virens is an ecologically and commercially important polychaete of intertidal soft sediment and an ideal species to investigate long term effects of metals. Using a spike approach, worms (1-3 g) were incubated for nine months in sediments spiked at environmentally relevant concentrations of copper, zinc and copper & zinc together: low (copper: 70 mg kg-1, zinc: 200 mg kg-1), medium (copper 120 mg kg-1, zinc: 270 mg kg-1) and high (copper 575 mg kg-1, zinc: 1160 mg kg-1) concentrations. These concentrations were based on an extensive sampling regime of sediment, pore water and worms from seven sites with different levels of contamination across the UK. Worms were fed and maintained under ambient conditions in a flow-through seawater system and sampled at 3, 6 and 9 months. Using BCR sequential extraction, bioavailable metal concentrations in the sediment were assessed in addition to pore water and tissues metal concentrations. The induction of metallothionein (MT) activity, especially at month 6, revealed the detoxification potential of N. virens under metal stress conditions. Significant correlations were obtained between copper bioavailable concentrations in the sediment and MT levels at month 3 and between zinc bioavailable concentrations in the sediment and MT levels at month 6. The highest DNA damage was recorded at month 3 for high copper & zinc combined treatment with 36.44%. Significant correlations were obtained between sediment bioavailable metal concentrations and DNA damage. In addition, the study of metal induced gene expression will reveal for the first time metal regulation process in the polychaete N. virens. This study showed that (1) not only high copper was toxic to N. virens but high copper & zinc combined treatment was the most toxic to the worms and (2) MT and DNA damage were sensitive and reliable endpoints used to evaluate copper and zinc toxicity. [less ▲]

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See detailEcological diversity of damselfishes (Pomacentridae) from Moorea
Gajdzik, Laura ULg; Parmentier, Eric ULg; Lepoint, Gilles ULg et al

Poster (2014, December)

The Pomacentridae (damselfishes) represents the 3rd most species-rich coral reef fish family, including 394 species spread worldwide. Recent studies suggested that damselfishes iteratively evolve along ... [more ▼]

The Pomacentridae (damselfishes) represents the 3rd most species-rich coral reef fish family, including 394 species spread worldwide. Recent studies suggested that damselfishes iteratively evolve along three main trophic guilds: “the pelagic feeders” feeding mainly on zooplankton, “the benthic feeders” grazing filamentous algae or biting coral polyps, and an “intermediate” group with species feeding on zooplankton, small benthic invertebrates and algae in variable proportions. Comparing the ecological diversity of damselfish communities among various geographical regions could assess such an iterative radiation. Within this context, the present study is a first attempt exploring the trophic diversity of damselfish community at Moorea Island (French Polynesia). The relationship between the trophic guilds, their habitat diversity and their behavior is evaluated. Habitat and behaviour of 16 damselfish species were described during transects along which different kinds of data were collected. For examples, the location within the reef (e.g. fringing or barrier reef), the depth, the substrate over which fishes are living or the solitary/gregarious habits were recorded. Diet of individuals was investigated by means of stomach content and stable isotopes analyses. Correlations between the dietary preferences and ecological data (habitat and behaviour) are given and the ecological diversity among trophic groups is compared. [less ▲]

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See detailWhat can we learn from asteroseismology of β Cephei stars through forward approach modelling?
Salmon, Sébastien ULg; Montalban, J.; Miglio, A. et al

Poster (2014, December)

The beta Cephei pulsating stars present a unique opportunity to test and probe our knowledge on the interior of massive stars. The information we can obtain depends on the quality and number of ... [more ▼]

The beta Cephei pulsating stars present a unique opportunity to test and probe our knowledge on the interior of massive stars. The information we can obtain depends on the quality and number of observational constraints, both seismic and classical ones. The asteroseismology of beta Cephei stars proceeds by a forward approach, which often result in multiple solutions, without clear indication on the level of confidence. We seek a method to derive confidence intervals on stellar parameters obtained by forward approach and investigate how these latter behave depending the seismic data accessible to the observer. We realise forward modelling with help of a grid of pre-computed models and use Monte-Carlo simulations to build confidence intervals on the inferred stellar parameters. We apply and test this method in a series of hare and hound exercises on a subset of theoretical models simulating observed stars. Results show that a set of 5 frequencies (with knowledge of their associated angular degree) yields good seismic constraints. In particular, presence of mixed modes provides a strong diagnosis on the evolutionary state of the star. Significant errors on the determinination of the extent of the central mixed region appear when the theoretical models do not present the same chemical mixture as the observed star. [less ▲]

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See detailEffect of tree species mixture on earthworm communities on a continental scale
De Wandeler, Hans; Baeten, Lander; Carnol, Monique ULg et al

Poster (2014, December)

The belowground food web represents a major part of associated biodiversity in forest ecosystems, and plays a significant role in the ecosystem processes of litter decomposition and nutrient turnover ... [more ▼]

The belowground food web represents a major part of associated biodiversity in forest ecosystems, and plays a significant role in the ecosystem processes of litter decomposition and nutrient turnover. Past research has demonstrated overwhelming evidence of strong tree species identity effects on earthworm communities. It has been proposed that increased plant community diversity would be beneficial to the abundance and diversity of the belowground food web, but effects of tree species diversity on earthworm communities have seldom been reported, and are inconclusive. In this study at continental scale we evaluated whether tree species diversity positively affects earthworm biomass and diversity. For this purpose the FunDivEUROPE Exploratory Platform was used with 209 plots in 6 regions well spread over Europe with a low within-region site variability, but a within-region tree species diversity gradient from monocultures to 3 or 4 species plots. In every plot earthworms were sampled using a combined method of mustard extraction and hand sorting of litter and a soil monolith. Data are being analysed with multivariate tools and mixed effects models. First results suggest only limited influence of tree diversity on the biomass of earthworm communities at continental scale. Tree diversity effects are weak, context specific and interacting with tree identity. In nutrient poor soils we found a negative tree diversity effect on earthworm biomass when deciduous monocultures are enriched with coniferous species, while in rich soils we found a positive tree diversity effect which could be related with the food security this provides to the earthworm community. [less ▲]

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See detailTaxonomic sufficiency for soft-bottom macrozoobenthos long term study - A case study in corsica
Donnay, Annick ULg; Pelaprat, Corinne; Lejeune, Pierre et al

Poster (2014, December)

Nowadays, the knowledge of the marine ecological quality status of an environment is essential and soft-bottom macrobenthos is one of the indicators used. Studies of soft-bottom macrobenthos are time ... [more ▼]

Nowadays, the knowledge of the marine ecological quality status of an environment is essential and soft-bottom macrobenthos is one of the indicators used. Studies of soft-bottom macrobenthos are time consuming and need expertise for organisms’ identification. Simplifications of these studies are tried and Taxonomic Sufficiency (TS) proposed by Ellis (1985) is one of research axes. For example, some studies highlight that family level identification could be sufficient to identify perturbed area (e.g: Bacci et al., 2009; De-La-Ossa-Carretero et al., 2012; Forde et al., 2013). Nevertheless, identification at species level could be recommended to have more precise information about the existing situation (Ajmal Khan, 2006) or to complete information from others levels (Conde et al., 2013). In Corsican waters where human impacts are less important than in main land waters, we present TS based on STARESO research studies between 2006 and 2012. This work is within the frameworks of the STARE-CAPMED program dedicated to STAtion of Reference and rEsearch on Change of local and global Anthropogenic Pressures on Mediterranean Ecosystem Drifts. After Permanova analysis and Canonical analysis of principal coordinates, eight habitat types have been identified along Corsican coastal water. Their own reference conditions and ecological class boundaries have been evaluated. Those reference conditions and ecological status have been identified for species, genus and family level. A highly significant correlation of calculated values between species and genus levels (R²=0.93) has been determined and a significant correlation between species and family level (R²=0.75). Genus and family levels have a significant Spearman correlation with species level (p<0.05). An application of these reference conditions on the macrobenthos assemblages sampling on 14 stations in spring 2011 and late summer 2012 in Calvi Bay highlights areas with high, good or moderate ecological status. In conclusion, family level is sufficient to follow spatial and/or temporal ecological status. [less ▲]

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See detailValidation d’un questionnaire d’ergonomie cognitive relatif au travail chez des patients atteints de sclerose en plaques
Blavier, Adelaïde ULg; DELRUE, Gaël ULg; HENNEN, Julie et al

Poster (2014, December)

We present datas validating the use of our QUIPSEP questionnaire among multiple sclerosis patients actually employed.

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See detailMagnetic Reconnection During Major Magnetospheric Storms
Hubert, Benoît ULg; Milan, S.E.; Cowley, S.W.H.

Poster (2014, December)

We combine imaging of the proton aurora from the SI12-IMAGE instrument with ionospheric convection measurement from the SuperDARN radar network to analyze the cycle of magnetic flux opening and closure of ... [more ▼]

We combine imaging of the proton aurora from the SI12-IMAGE instrument with ionospheric convection measurement from the SuperDARN radar network to analyze the cycle of magnetic flux opening and closure of the Earth magnetosphere. Interaction between the solar wind and the Earth geomagnetic environment causes a reconfiguration of the magnetic field that connects the interplanetary magnetic field (IMF) to the geomagnetic field. This reconnection process produces open magnetic field lines (i.e. field lines of the magnetosphere that close through the interplanetary medium) that are dragged to the magnetotail by the solar wind flow, where they eventually reconnect again, back to a closed topology. The SI12 imaging of the Doppler-shifted Lyman-α emission of the proton aurora is used to estimate the location of the boundary separating open and closed field lines at ionospheric altitude. We then estimate the open magnetic flux of the Earth magnetosphere, encircled by this boundary. The rate of reconnection causing a variation of the open magnetic flux can be expressed as a voltage in application of Faraday’s law. This voltage is measured along the open/closed field line boundary determined from the imaging data. The electric field associated with the voltage has two origins: motion of the boundary and the ionospheric field. We use the ionospheric electric field deduced from ionospheric convection measurement from the SuperDARN to estimate the reconnection voltage at the magnetopause (flux opening) and in the magnetotail (flux closure) accounting for the motion of the open/closed field line boundary determined from the SI12 images. The method is applied during several (strong) geomagnetic storms. These intervals are characterized by large values of open flux and reconnection rates, as a result of coupling between the solar wind and the geomagnetic environment. We present these results in terms of a magnetospheric mode that develops under strong coupling with the solar wind, a condition known to be prone to the development of sawtooth events, characterized by overloading of the magnetosphere with open magnetic flux. [less ▲]

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See detailFatigue et auto-évaluation chez des patients atteints de sclérose en plaques
DELRUE, Gaël ULg; Blavier, Adelaïde ULg; HENNEN, Julie et al

Poster (2014, December)

Different fatigue scales specific for multiple sclerosis patients correlate quite differently with other psychological measures which gives rise to a necessary reflexion about the tools used in clinical ... [more ▼]

Different fatigue scales specific for multiple sclerosis patients correlate quite differently with other psychological measures which gives rise to a necessary reflexion about the tools used in clinical practice and their meanings. [less ▲]

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See detailPoster session 6: Saturday 6 December 2014, 08:30-12:30Location: Poster area.
Henri, C.; DULGHERU, Raluca Elena ULg; Magne, J. et al

Poster (2014, December)

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See detailIntentions d'implémentation et procrastination chez les étudiants.
Stassart, Céline ULg; Potdevin, Benoit; Etienne, Anne-Marie ULg

Poster (2014, December)

Introduction : La procrastination est définie comme une tendance à reporter ce qui est nécessaire pour atteindre un objectif. Ainsi, la procrastination concerne une intention qui ne se traduit pas en ... [more ▼]

Introduction : La procrastination est définie comme une tendance à reporter ce qui est nécessaire pour atteindre un objectif. Ainsi, la procrastination concerne une intention qui ne se traduit pas en action. L’intention d’implémentation se définit notamment à travers le désengagement face au problème, l’orientation vers les buts, et l’activation des ressources et cette étude examine la part explicative de ces trois dimensions dans le processus de procrastination. Méthodologie : Un échantillon de 197 étudiants ont complété les versions françaises du Solution Focused Inventory (SFI), et du Procrastination Assessment Scale for Students (PASS). Résultats : L’intention d’implémentation intervient dans 32% de la variance de la procrastination. Le désengagement face au problème et l’orientation vers les buts expliquent de manière significative la fréquence de procrastination.  Conclusion : Le processus de procrastination pourrait en partie être expliqué par manque d’intentions d’implémentation, plus particulièrement par une difficulté à se désengager du problème (tendance à être bloqué dans sa réflexion en se focalisant davantage sur les problèmes) et à s’orienter vers les buts (présenter des difficultés à mettre au point des plans d’action efficaces). [less ▲]

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See detailThe effects of Triclosan on the metabolism of developing Sheepshead minnow (Cyprinodon variegatus) larvae
Lallemand, Lise; Voisin, Anne-Sophie; Darchambeau, François ULg et al

Poster (2014, December)

The aquatic environment represents the final sink for many chemicals, including bactericidal agents. Among them Triclosan (TCS) has been shown to affect the thyroid system of teleost. Thyroid hormones are ... [more ▼]

The aquatic environment represents the final sink for many chemicals, including bactericidal agents. Among them Triclosan (TCS) has been shown to affect the thyroid system of teleost. Thyroid hormones are involved in the control of metabolism, so changes in hormone levels induced by triclosan may affect respiratory rates and antioxidant stress in exposed fish. Couples of three females and two males were placed in breeding chambers designed for this experiment. Eggs were collected and maintained in seawater. Embryos were selected under a dissection microscope, randomly assigned to each of five treatment groups: Control, DMSO control, 20 μg/L TCS, 50 μg/L TCS and 100 μg/L TCS and placed in incubation dishes (50 per dish) at 25°C. On day 6, embryos hatched and larvae were transferred to 1L dishes. The larvae were fed on artemias and on flaked fish food till day 15 and 30 post hatching when the fish were analyzed. Respiratory rate measurements were carried out by respirometry and assays of antioxidant enzymes, Glutathionreductase (GR), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) were conducted to determine the presence of oxidative stress. Respirometry showed that TCS exposed fish exhibited decreased the metabolism at 15 dph, whereas no differences in respiration rate could be observed between control and exposed larvae at 30 dph. At 15 dph no difference was observed for any of the antioxidant enzymes, whereas at 30 dph a sharp increase in the activity of GR was observed between the control and TCS exposed fish. The activity of GST and Gpx remained stable. Thyroid hormones are major factors controlling the metabolic rate related to respiration and oxidative stress. TCS reduced the metabolism at 15 dph that corresponds to the moment where larvae to juvenile transition of Sheepshead minnows occur. Previous experiments showed that TCS induces an increase in thyroid hormone concentrations and hyperthyroidism induces oxidative stress. So our observed increase of antioxidant protection mechanisms could be a way to compensate oxidative stress. On the other hand, the changes in GR activity observed at 30 dph, may also be related to the reduced metabolism at 15 dph. [less ▲]

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See detailClub 35 Poster session 2: Thursday 4 December 2014, 08:30-18:00Location: Poster area.
Voilliot, D.; Magne, Jm; DULGHERU, Raluca Elena ULg et al

Poster (2014, December)

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See detailPoster session 4: Friday 5 December 2014, 08:30-12:30Location: Poster area.
Uejima, T.; Itatani, K.; Nakatani, S. et al

Poster (2014, December)

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See detailTrace element kinetics in caged Mytilus galloprovincialis
Richir, Jonathan ULg; Lepoint, Gilles ULg; Donnay, Annick et al

Poster (2014, December)

Trace elements (TEs) remain contaminants of concern because of their persistence, ability to concentrate in organisms and toxicity. The Mediterranean mussel Mytilus galloprovincialis Lamarck, 1819 is a ... [more ▼]

Trace elements (TEs) remain contaminants of concern because of their persistence, ability to concentrate in organisms and toxicity. The Mediterranean mussel Mytilus galloprovincialis Lamarck, 1819 is a relevant bioindicator of TE coastal contamination. However, little research has studied the combined influence of environmental condition changes and physiological processes on their kinetics in that species. Caged M. galloprovincialis were thus immerged in 2 contrasted pristine Corsican (France) coastal environments, the semi-enclosed Diane salty pond and the open Calvi Bay, from February to June 2011. Mussels were regularly sampled to study the kinetics of 19 TEs in their flesh; dissolved and particulate TEs were also monitored. The primary production and the water physico-chemical variables were measured, and meteorological data were purchased from Météo-France. TE kinetics in mussels differed between sites. Mussel spawning, a temperature and saline-induced physiological process that occurred about 10 days later in the Diane pond, was followed by a short time increase of TE levels in the mussel flesh. Mussel contamination also evolved according to changes of their respective environmental TE levels. Raining events temporary led, in the Diane pond, to the water enrichment with TEs, nutrients and detrital material, to peaks of primary production and to the increase of TE concentrations in the mussel flesh. This step by step evolution of TE levels in the environment and mussels was afterwards followed by a rapid return to initial conditions. In the open Calvi Bay, these fast and balanced kinetics were not so obvious, because of the rapid dilution of environmental constrain effects in the Bay. Mussels are often used as bioindicator in estuaries and coastal enclosed meadows with rapidly changing environmental conditions. In such conditions, the influence of the environment on TE kinetics in mussels must be considered, in addition to physiological processes, when monitoring the TE coastal contamination. [less ▲]

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See detailCytoskeletal changes in supporting cells of the auditory organ during development in rodents: the appearance of 15-protofilament microtubules and β5-tubulin isoform.
Renauld, Justine ULg; Thelen, Nicolas ULg; Johnen, Nicolas et al

Poster (2014, December)

A feature of the supporting cells of the organ of Corti is the presence of an abundant cytoskeleton which is mainly composed of microtubules. These supporting cells have also been shown to contain a minor ... [more ▼]

A feature of the supporting cells of the organ of Corti is the presence of an abundant cytoskeleton which is mainly composed of microtubules. These supporting cells have also been shown to contain a minor mammalian tubulin, the β5-tubulin [1], recently reported to be a biomarker for cancer outcome [2] and cell proliferation [3]. It was shown that a β-tubulin isoform can specify the microtubule architecture, as seen with the expression of the Moth β2 tubulin in the Drosophila testes which imposes the 16-protofilament (16pf) structure on the corresponding subset of Drosophila microtubules, which normally contain 13pf [4]. Moreover, supporting cell microtubules are formed by 15pf instead of the canonical 13, a unique fact among vertebrates [5]. Such a protofilament configuration has been observed in C. elegans’ neurons which are responsible for the mechanosensory sense of touch [6]. It was also shown that these 15pf microtubules were essential to the proper functioning of these mechanosensory neurons [6]. To determine the role of this particular tubulin in the auditory organ and its possible involvement in the formation of the unusual 15pf microtubules of supporting cells, we studied the spatiotemporal localization of β5-tubulin during development in rats from embryonic day 18 until P25 (25th postnatal day). Then we examined the fine structure of microtubules at the transmission electron microscope level. Our results showed that β5-tubulin, contrary to other β-tubulins, had a unique distribution in the cochlea. This β-tubulin appeared at a postnatal stage, before the opening of the Corti’s tunnel and are restricted to supporting cells, especially in pillar and Deiters’ cells. Electron microscopy further indicated that pillar and Deiters cells were composed by 13pf microtubules at P2, but by 15pf microtubules at P25. In conclusion, the architecture of microtubules seems to evolve during the development of the organ of Corti. Furthermore, β5-tubulin has the same localization than this structure and could be an interesting target. [less ▲]

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See detailOn Damage Characterization of a Steel Sheet
Guzmán Inostroza, Carlos Felipe ULg; Habraken, Anne ULg

Poster (2014, December)

Ductile damage is a physical phenomena which involves progressive deterioration of mechanical properties of metals, when undergoing high deformations. Compared to plasticity, the physical mechanisms ... [more ▼]

Ductile damage is a physical phenomena which involves progressive deterioration of mechanical properties of metals, when undergoing high deformations. Compared to plasticity, the physical mechanisms behind damage are more complex and the microscale is not longer negligible. In mathematical damage models, founding an optimal set of material parameters can be a hard task due to the strong coupling and non-linearity of the equations. An identification strategy is then crucial to arrive to a general set of parameters. Therefore, we address the fully characterization of a ferritic steel sheet, involving the elasto-plastic and damage parameters. This poster presents an hybrid experimental-numerical procedure, coupling numerical simulations, optimization algorithms and digital image correlation measurements, over a set of representative experimental and numerical results of tensile, shear and plane strain tests in different material directions. Due to the small thickness of the sheet, the constitutive model is very prone to localization into a shear band difficulting the damage parameters identification. It is found that a porosity induced inhomogeneity plus a mixed hardening can delay localization and represent the entire deformation range of the tests, leading to acceptable results. Different set of parameters are also obtained and then validated with experimental results. This localization phenomena should be carefully considered in applications involving complex strain paths. [less ▲]

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See detailPerceptions culturelles dans un contexte de néoplasme pédiatrique: Considérations transculturelles entre l’Occident et le Japon
Vander Haegen, Marie ULg; Roskam, Isabelle

Poster (2014, November 29)

INTRODUCTION Toute société humaine construit son héritage collectif sur la transmission de valeurs et de rites permettant aux descendants de réguler leurs schèmes comportementaux, affectifs, sociaux et ... [more ▼]

INTRODUCTION Toute société humaine construit son héritage collectif sur la transmission de valeurs et de rites permettant aux descendants de réguler leurs schèmes comportementaux, affectifs, sociaux et moraux sur base des repères culturels alloués depuis des décennies. Investiguer les balises culturelles et l’appréhension sociétale du néoplasme pédiatrique reste peu développé dans la littérature. Ce champ « anthropo-clinique » prend initialement son essor dans la clinique oncologique adulte où des résultats significatifs montrent un lien entre la culture et la perception du cancer. OBJECTIFS Les objectifs de cette étude sont multiples: (a) étudier l’effet de la culture dans la représentation de la maladie cancéreuse de l’enfant, (b) analyser transculturellement les similitudes et les dissimilitudes entre la culture japonaise et occidentale, et (c) mettre en exergue les diverses implications cliniques pour les professionnels de la santé. METHODE Une revue de littérature est conduite afin de dégager les tendances culturelles dans la politique sanitaire, le service hospitalier, la relation médecin-malade, le concept de douleur, l’environnement familial et la perception de la mort au Japon et en Occident. Le choix s’est porté sur ce pays asiatique par la présence de certains repères culturels intéressants dans le domaine de l’oncologie pédiatrique. RESULTATS (a) Etudier l’effet de la culture dans la représentation de la maladie cancéreuse de l’enfant Les correspondances effectuées ont permis d’entrevoir la situation onco-pédiatrique comme relevant de faits biologiques et de faits culturels. Les paramètres culturels interviennent au sein des nombreuses conceptions et représentations sociales de la maladie cancéreuse d’un enfant. L’ensemble de ces perceptions sociales étant notamment influencées par les valeurs et les truismes véhiculés dans la culture. (b) Analyser transculturellement les similitudes et les dissimilitudes entre la culture japonaise et occidentale. Eléments de similitudes : Il a été noté l’universalité des mécanismes pathogéniques du cancer chez l’enfant et le développement de politiques sanitaires dans la lutte contre le cancer. Eléments de dissimilitudes : A. Le Japon Le système familial japonais et son organisation des soins en cancérologie de l’enfant varient et se teintent de nombreuses coutumes shintoïstes et bouddhistes. Il a été identifié le chaos régnant dans ses familles où des attitudes désengagées existent. L’organisation hospitalière japonaise est décrite comme carencée en réseaux de soutien psychologique pour la mère, très souvent seule face à la maladie de son enfant. Des risques majeurs de dépression, de traits anxieux et d’un stress post-traumatique sont observés. Le médecin japonais dispose d’un pouvoir de décision médicale et sociale, se manifestant notamment par un degré de variabilité dans la communication diagnostique et pronostique envers la famille et l’école d’origine. La situation de soin est variable avec l’inclusion en premier lieu d’une pharmacopée naturelle afin de traiter le cancer et ses effets iatrogènes. Enfin, il subsiste une inhibition du partage social des émotions où, des attitudes de retenue et de silence chez les parents se manifestent durant tout le processus thérapeutique mais aussi en cas de décès de l’enfant. B. L’Occident Les pays occidentaux présentent une appréhension sociale et médicale singulière du cancer pédiatrique. La variabilité observée concerne l’organisation hospitalière et la communication médicale. Le praticien occidental établit une communication médicale ouverte avec l’enfant et sa famille et ce, dès le départ du processus thérapeutique. Le contexte curatif est caractérisé par une forte médication d’opioïdes afin de pallier aux nombreuses douleurs et effets des traitements. L’aménagement hospitalier permet la création de réseaux de soutien psychologique pour l’enfant et sa famille et l’établissement d’activités ludiques.(c) Mettre en exergue les diverses implications cliniques pour les professionnels de la santé L’intention de cette étude est de sensibiliser les professionnels de la santé à la pléiade de facteurs psycho-sociaux intervenant dans un contexte de maladie néoplasique. Éléments qui doivent requérir d’une bienveillance clinique où tant l’enfant traité que son entourage familial, doivent être entendus dans toute leur spécificité d’être humain. DISCUSSION Une stratégie d’action intéressante concernerait une grille de lecture culturelle du patient et de sa famille. Cette grille peut offrir un entendement de la diversité culturelle en psycho-oncologie et peut permettre au professionnel de réajuster finement son travail clinique dans un contexte quotidien de multiculturalité. Cette grille de lecture doit rester simple et proposer un petit nombre de « repères culturels » (items culturels) pour professionnels, leurs permettant d’ajuster certains paramètres cliniques (communication médicale, gestion des émotions, rapport à la mort, etc.). Cette considération ethnologique du patient doit supposer au préalable une formation de compétences dans le domaine de la culture et de la santé/maladie. [less ▲]

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See detailDélires et Hallucinations : Echelle transdiagnostique d’auto-évaluation.
Beaupain, Margaux; Thirion, Julie; Wagener, Aurélie ULg et al

Poster (2014, November 29)

Introduction : Les délires et les hallucinations sont des symptômes majeurs présents chez 80% des personnes souffrant d’un trouble psychotique (e.g., bipolaire, schizophrène). Cependant, ces phénomènes ... [more ▼]

Introduction : Les délires et les hallucinations sont des symptômes majeurs présents chez 80% des personnes souffrant d’un trouble psychotique (e.g., bipolaire, schizophrène). Cependant, ces phénomènes sont également présents dans d’autres troubles psychiatriques (e.g., troubles anxieux, dépression) et chez 8% des individus tout venants (Linscott & Van Os, 2012) suggérant l’importance de les évaluer. D’après la littérature, les populations cliniques et non-cliniques se distinguent d’avantage à travers différentes dimensions telles que la détresse, la conviction et le contenu que par la fréquence (Lincoln, 2007). Cependant, les évaluations existantes se centrent principalement sur la fréquence des phénomènes, ce qui laisse beaucoup d’informations cliniques de côté. De plus, elles ne sont que rarement basées sur une approche en continuum permettant d’appréhender la complexité et l’hétérogénéité des phénomènes (allant des perceptions aberrantes jusqu’aux délires et hallucinations). Enfin, ce sont souvent des hétéroévaluations qui sont chronophages et requièrent du personnel qualifié alors que certaines études suggèrent une bonne validité des autoévaluations de ces phénomènes (Se Hyun et al., 2010). Afin de pallier ces limites, nous avons développé une échelle transdiagnostique d’auto-évaluation des idées délirantes et hallucinations en se basant sur une approche en continuum. Méthode : Une revue de la littérature sur les caractéristiques et outils d’évaluations des idées délirantes et des hallucinations a été réalisée. Vingt-quatre items parmi les plus discriminants ont été sélectionnés et adaptés. Pour chaque item, huit dimensions ont été sélectionnées : fréquence, détresse, interférence, conviction, état de conscience, contenu positif VS négatif, agréabilité et attribution interne VS externe. Les individus répondent d’abord à la fréquence sur une échelle de type Likert en 5 points (« Oui, ça m’arrive souvent » à « Non, ça ne m’est jamais arrivé »). Si la réponse est positive, les sept autres dimensions sont évaluées via une échelle visuelle analogique de 0 à 10. Perspectives: L’échelle est actuellement en cours de validation. Elle sera pré-testée auprès d’étudiants avant d’être validée auprès de populations cliniques et non-cliniques. A long terme, cette échelle transdiagnostique d’auto-évaluation pourrait être utilisée en clinique comme un outil favorisant une meilleure prise en charge de ces symptômes et comme un nouvel outil de recherche. [less ▲]

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See detailTracking stressed blood volume during vascular filling experiments
Pironet, Antoine ULg; Dauby, Pierre ULg; Chase, J. Geoffrey et al

Poster (2014, November 28)

A three-chamber cardiovascular system model is used to compute stressed blood volume from filling experiments. As previously observed, stressed blood volume is a good predictor of the change in cardiac ... [more ▼]

A three-chamber cardiovascular system model is used to compute stressed blood volume from filling experiments. As previously observed, stressed blood volume is a good predictor of the change in cardiac output after fluid infusion. [less ▲]

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See detailFunctional analysis of FRD3 in Arabidopsis relatives
Scheepers, Maxime ULg; Charlier, Jean-Benoit ULg; Motte, Patrick ULg et al

Poster (2014, November 28)

Transcriptomic studies identified genes which are constitutively over-expressed in A. halleri compared to A. thaliana and which may have a role in metal tolerance or accumulation (1-3). A candidate gene ... [more ▼]

Transcriptomic studies identified genes which are constitutively over-expressed in A. halleri compared to A. thaliana and which may have a role in metal tolerance or accumulation (1-3). A candidate gene encodes FRD3, a member of the MATE family of membrane transporters (56 members in A. thaliana). It is a citrate transporter involved in iron homeostasis (4-6) and playing a role in zinc tolerance in A. thaliana (7). We are aiming to analyse the FRD3 high expression in A. halleri and the FRD3 function in zinc and iron homeostasis in A. thaliana. [less ▲]

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See detailEstimating Ventricular Stroke Work from Aortic Pressure Waveform
Kamoi, Shun; Pretty, Christopher; Chiew, Yeong Shiong et al

Poster (2014, November 28)

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See detailCréation d'un stage obligatoire de médecine générale, pour tous les étudiants de 6e année en médecine
Dumont, Virginie ULg; Burette, Philippe ULg; MASSART, Valérie ULg et al

Poster (2014, November 27)

Introduction : Depuis 2013, un stage obligatoire d'un mois de Médecine générale (MG) a été accepté par la faculté, pour tous les étudiants de 6ème année. Il vient compléter un court stage de découverte de ... [more ▼]

Introduction : Depuis 2013, un stage obligatoire d'un mois de Médecine générale (MG) a été accepté par la faculté, pour tous les étudiants de 6ème année. Il vient compléter un court stage de découverte de la MG, programmé depuis 10 ans en 4ème année. Les objectifs sont de permettre à tous étudiants, quelle que soit leur future spécialité, de comprendre le rôle du généraliste auprès des patients et dans le système de santé, d'acquérir des habilités professionnelles utiles à tous et de susciter de l'intérêt pour la MG. Objectif : Sur base de ces objectifs, les généralistes enseignants ont élaboré des activités programmées en stage et à l'université. Ensuite, ce dispositif a été soumis à des étudiants sortant de 6ème année: leurs besoins de formation ressentis ont donc été pris en compte dans la structure finale. Les maitres de stage (MDS) ont été formés spécifiquement à ce nouveau dispositif. Méthode et moyens : Le stage est organisé mensuellement pour un groupe de 15 étudiants. Un carnet de stage commun aux stagiaires et MDS, décrit les activités obligatoires et facultatives à réaliser. Les étudiants participent activement à la vie professionnelle de leur MDS en première ligne, et reviennent pour 3 demi-journées à l'université. Des ateliers y sont programmés : recueil des représentations de la MG et besoins des étudiants, examen clinique, apprentissage à l'entrevue médicale font partie des modalités proposées lors de ces demi-journées. Les étudiants sont également invités à échanger sur leur vécu et apprentissage lors de ce stage. Résultats attendus : Le département a investi des moyens humains importants dans un suivi rapproché des étudiants et des MDS. Il en attend une amélioration des aptitudes cliniques de base et une meilleure visibilité de la MG en formation initiale. [less ▲]

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See detailRole of the polyQ length and non-polyQ regions during the aggregation process into amyloid fibrils of model polyQ proteins
Huynen, Céline ULg; Willet, Nicolas ULg; Buell, Alexander K et al

Poster (2014, November 26)

Nine neurodegenerative disorders, referred to as polyglutamine diseases and including Huntington’s disease, are associated with the abnormal expansion of a polyglutamine tract inside nine unrelated ... [more ▼]

Nine neurodegenerative disorders, referred to as polyglutamine diseases and including Huntington’s disease, are associated with the abnormal expansion of a polyglutamine tract inside nine unrelated proteins. This polyQ expansion is thought to be the major determinant in the development of neurotoxicity, triggering protein aggregation into amyloid fibrils. A large body of evidence however suggests that non-polyQ regions modulate the aggregation process triggered by polyQ expansions. The interplay between the polyQ tract and non-polyQ regions is complex and still not fully understood. In order to better understand it, we previously designed and characterized model polyQ proteins made of the beta-lactamase BlaP with 23, 30, 55 and 79Q inserted at position 197 or 216. Our first results had indicated that our model is relevant to study polyQ aggregation since it recapitulates the aggregation properties of polyQ disease-associated proteins: there is a Q-threshold for the spontaneous formation of amyloid fibrils in solution, and above the threshold, the longer the polyQ, the faster the aggregation. Moreover, the structure of BlaP and the position of insertion of the polyQ tract influence their aggregation properties in solution. This work aims to better understand, at the molecular level, (i) the precise role of the polyQ length (23, 30, 55, 61, 67, 73 and 79Q), (ii) the conformation of the host protein (native or unfolded BlaP), (iii) the location of the polyQ tract within BlaP (197 or 216), (iv) the flexibility of the polyQ flanking sequences, and (v) the origin of constraints applied by BlaP to the inserted polyQ tract (at its N- or C-terminal end) on the structural, thermodynamic and aggregation properties of BlaP-polyQ chimeras, using a wide range of biophysical techniques (e.g., spectroscopy methods, quartz crystal microbalance, atomic force microscopy and dynamic light scattering). The effect on the aggregation properties will be determined on the spontaneous aggregation into amyloid fibrils in solution, and on the nucleation and on the elongation steps of amyloid fibril formation. For this purpose, new chimeras containing 61, 67 and 73Q at position 197, or 55Q inserted at position 197 in between two different protease’s cleavage sites, that are relatively flexible, will be moreover created. Our results first demonstrate that the spontaneous aggregation into amyloid fibrils in solution is correlated to the polyQ length with an exponential growth function, and that the elongation rate is linearly correlated to the polyQ length, independently of the protein context (i.e., conformation of BlaP, and/or location of the polyQ tract, and/or polyQ peptides inserted or not within BlaP). However, the location of the polyQ tract inside BlaP, and/or its conformational state, and/or the flexibility of polyQ flanking sequences, and/or the origin of constraints applied to the polyQ tract drastically influence the ability of a polyQ tract to trigger the nucleation and/or the elongation step of amyloid fibrils (variation in the Q-threshold and in the absolute rate of both steps). Altogether, our results suggest that non-polyQ regions constitute an additional potential therapeutic target, more specific than drugs targeting the polyQ sequence, to interfere with the nucleation and/or the elongation of amyloid fibrils, associated to neurotoxicity. A possible drug could be constituted by a ligand specific to non-polyQ regions of disease-associated proteins, which further increases the constraints applied to the polyQ expansion to prevent the disease onset and/or progression. [less ▲]

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See detailUse of 13C-NMR in structural elucidation of polysaccharides: case of locust bean gum
Gillet, Sébastien ULg; Aguedo, Mario ULg; Blecker, Christophe ULg et al

Poster (2014, November 25)

Locust bean gum (LBG) galactomannans are polysaccharides consisting of a β-(1→4) D-mannopyranosyl backbone substituted to varying degrees in α-(1→6) with single D-galactopyranosyl residues. This basic ... [more ▼]

Locust bean gum (LBG) galactomannans are polysaccharides consisting of a β-(1→4) D-mannopyranosyl backbone substituted to varying degrees in α-(1→6) with single D-galactopyranosyl residues. This basic structure is the same for all galactomannans (Fig. 2). However, when locust bean gum is extracted at different temperatures, the generated fractions exhibit different properties in aqueous solution (viscosity, viscoelasticity, gel formation, thermohydrolysis resistance, etc.). This means that there are differences within the fine structure of the polymers (although the basic structure is the same). Analysis of [13C]-NMR spectra of galactomannans, in combination with other techniques, can provide capital information about fine structural elucidation of the polymers. The method specifies the distribution of lateral galactosyls along the main chain of mannans. Two fractions extracted from locust bean gum at 25 and 80 °C (respectively GM25 and GM80) were comparatively studied by [13C]-NMR. Mannosyls/Galactosyls (M/G) ratios can be determined by considering the intensities of C-1 mannose and galactose signals in [13C]-NMR spectra. This method provides results relatively close to those obtained by GC-MS analysis. Spectra also showed that resonance from C4 of D-mannose residues were split, in evident dependence upon the nearest-neighbor probabilities (“diad frequencies”) of D-galactosyl groups along the mannan chains (Fig. 2). Diad frequencies were obtained by integrating C4(Man) peak areas. F11, F21/F12 and F22 gave respectively the di-, mono- or non-substituted mannose pairs proportions. High percentages of F11 and F22 therefore indicate a more non-homogeneous distribution of lateral galactosyls along the polysaccharide backbone as observed for GM80. The percentages of total lateral substituents obtained by C4(Man) peak analysis [F11 + (F21 or F12)/2] were fairly well correlated with M/G ratios. Splitting of the C-6 substituted D-mannose resonance provides, therefore the basis for determining the next-nearest-neighbor probabilities (triad frequencies) (Fig. 2). However, the spectrum is often not sufficiently resolved to accurately quantify and interpret the results. [less ▲]

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See detailImpact of steam explosion treatment on chemical configuration of Tall Fescue lignin : structural elucidation using NMR spectroscopy
Maniet, Guillaume ULg; Jacquet, Nicolas ULg; Gillet, Sébastien ULg et al

Poster (2014, November 24)

In the economic and energy context of our society, it is universally recognized that alternatives to petrochemicals products must be found. To overcome this problem, renewable lignocellulosic biomass ... [more ▼]

In the economic and energy context of our society, it is universally recognized that alternatives to petrochemicals products must be found. To overcome this problem, renewable lignocellulosic biomass could be used to produce high value products. To achieve this objective, pretreatment processes are required to allow the breakdown of lignocellulosic structure and increase accessibility of the material. In this way, steam explosion is a thermo-mechano-chemical pretreatment which allows the opening of lignocellulosic material structural components and includes modifications of the physical properties of the material, hydrolysis of hemicellulosic components and modification of the chemical structure of lignin [1]. This study is focused on the impact of various steam explosion treatments on the chemical configuration of tall fescue lignin. NMR analyses perform on the Festuca L. pretreated samples show variations of links with treatment intensity. Observations show double phenomen :re-polymerization and depolymerization of the lignin structure during steam explosion process [2]. In parallel, HPSEC analyses show modifications in the molecular weight of the lignin obtained after the steam explosion treatment. [less ▲]

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See detailIdentification, Design and Evaluation of Pharmacological tools for the orphan GPCR GPR22
Geubelle, Pierre ULg; Gilissen, Julie ULg; Dupuis, Nadine ULg et al

Poster (2014, November 21)

GPCRs are the largest family of membrane receptors and are characterized by seven transmembrane domains. This family of receptors is currently the most successfully targeted protein for therapeutic ... [more ▼]

GPCRs are the largest family of membrane receptors and are characterized by seven transmembrane domains. This family of receptors is currently the most successfully targeted protein for therapeutic purposes. GPR22 is a GPCR that was discovered in 1997. It has no known endogenous ligand and is thus considered "orphan". Its presence situated at the heart and brain levels makes it a potential target for new therapeutic pathways. The only information about its signaling channel could be its coupling with G proteins. This study consist in the identification of a synthetic ligand of GPR22 receptor to use it as a pharmacological tool in the study of the signaling channels of GPR22 in order to understand its role and to validate it as a new therapeutic target. The initial hypothesis was that GPR22 is coupled to the Gαi protein. [less ▲]

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See detailLes habitudes de sommeil chez l'enfant: indices de psychopathologie?
SCHOLL, Jean-Marc ULg; PHILIPPE, Paule ULg; Magis, David ULg

Poster (2014, November 21)

Objectif : investiguer chez l’enfant les habitudes d’endormissement en fonction de l’âge et de la présence ou non de psychopathologie(s) pour tester 2 hypothèses : 1) L’évolution développementale des ... [more ▼]

Objectif : investiguer chez l’enfant les habitudes d’endormissement en fonction de l’âge et de la présence ou non de psychopathologie(s) pour tester 2 hypothèses : 1) L’évolution développementale des habitudes de sommeil est différente et plus lente chez les enfants présentant une psychopathologie par rapport aux enfants « typiques ». 2) Les difficultés à l’endormissement sont plus fréquentes chez les enfants présentant une psychopathologie Méthodes : 15 questions simples concernant des habitudes de sommeil ont été posées aux parents de 2 groupes d’enfants âgés de 2.6 à 13 ans: 827 enfants « typiques » et 298 enfants « atypiques » suivis dans des consultations psychologiques ambulatoires. Le traitement statistique des données permet une étude développementale qui compare les habitudes de sommeil entre les 2 groupes ainsi que leur évolution en fonction de l’âge de l’enfant dans chaque groupe. Des courbes de percentiles pour chaque réponse nominale (toujours, souvent, parfois, rarement, jamais) ont été calculées en fonction de l’âge et du groupe. Résultats : Les analyses des réponses aux 15 questions: - 14 montrent des différences statistiquement significatives entre les 2 groupes (couche-tard/ durée d’endormissement/ appelle, sort de sa chambre, recherche de la compagnie/ s’occupe avec des jeux dans sa chambre avant de dormir/ exprime le souhait de s’endormir avec un frère, une sœur, un parent…) ; - 12 montrent des variations significatives des réponses avec l’âge de l’enfant ; - Pour 5 questions, les résultats montrent que l’effet de l’âge est différent suivant les groupes alors qu’inversement, pour 2 questions, l’effet de l’âge est identique dans les 2 groupes. Conclusion : Les résultats obtenus valident de façon très significative nos 2 hypothèses : 1) L’évolution développementale des habitudes de sommeil est différente et plus lente chez les enfants avec psychopathologie. 2) Les difficultés à l’endormissement sont plus fréquentes dans ce même groupe d’enfants. Nous pouvons en conclure qu’investiguer les habitudes de sommeil chez l’enfant grâce à des questions simples peut fournir des indices de psychopathologie et se révèle d’un très grand intérêt dans la clinique pédopsychiatrique. [less ▲]

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See detailCaractérisation préliminaire de quelques variétés d’amande cultivées dans la région orientale du Maroc
Houmy, Nadia; Elmoudden, S.; Boujnah, M. et al

Poster (2014, November 21)

L’amande est un fruit sec riche en huile, protéines, glucides et vitamines. Il est consommé tel quel (séché, grillé) ou transformé sous d’autres formes tel que la pâte d’amande. L’huile d’amande est très ... [more ▼]

L’amande est un fruit sec riche en huile, protéines, glucides et vitamines. Il est consommé tel quel (séché, grillé) ou transformé sous d’autres formes tel que la pâte d’amande. L’huile d’amande est très utilisée en dermatologie pour ses propriétés cosmétiques, adoucissantes et hydratantes. Ce travail de recherche appliquée est mené en collaboration avec la DRA-oriental et la DPA d’Oujda. Il s’agit d’une contribution au développement la filière amandier dans la région qui porte sur la valorisation de l’amande et ces dérivées principalement l’huile et le tourteau d’amandes. Dans cette étude préliminaire les huiles et tourteaux de 5 variétés cultivées dans la région orientale (Marcona, Ferragnes-Ferraduel, Fournat et Beldi) ont été analysées. Les amandes ont été fournis par la coopérative Sidi Bouhria-Oujda et l’extraction mécanique d’huiles d’amandes des 5 principales variétés (Marcona, Ferragnes-Ferraduel, Fournat et Beldi), cultivées dans la région orientale a été réalisée par une presse à huile au niveau de la société PRODIGIA (Casablanca). Dans ce cas et selon la variété, les rendements en huile varient entre 46 et 60% MS. Le rendement en huiles par extraction chimique diffère de celui réalisé par presse mécanique. La différence est nette dans le cas de variété Marcona connue pour sa richesse en fibres. Les analyses chimique portent sur l’acidité des huiles d’amandes qui se situe entre 0,0197 et 0,0491%, Indice de Peroxyde se varie entre 6,43 et 16,4 (meq./kg) et la détermination des profils des acides gras (AG). A ce propos les profils d’acides gras des cinq variétés montrent trois AG majoritaires qui sont par ordre d’importance l’acide oléique (C18 :1), acide linoléique (C18 :2) et l’acide palmitique (C16) et dont les teneurs se situent respectivement entre 63,54-72,87% pour C18 :1, 17,84- 25,45% pour C18 :2 et 6,53 et 7,91% pour C16. La comparaison quantitative d’acides gras majoritaires montre une différence significative entre les variétés analysées. Le tourteau comme sous-produits de trituration mécanique contient toujours une quantité résiduelle d’huile, leurs teneurs en protéines totaux se situent entre 47 et 49 % MS et leurs teneurs en sucre totaux se situe entre 12,6 à 14%.MS. Il s’agit là d’un coproduits de trituration qui est également riche en fibres et qui mérite d’être valorisé par voie de technologie alimentaire. [less ▲]

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See detailIn vitro study toward the endocrine activity and the genotoxic potential of migration products from plastic baby bottles
Simon, Coraline ULg; Onghena, M.; Covaci, A. et al

Poster (2014, November 20)

Bisphenol A (BPA) is used since 1960 as a primary raw material for the production of polycarbonate (PC) plastic and epoxy resin, widely used in a variety of common products including digital media (e.g ... [more ▼]

Bisphenol A (BPA) is used since 1960 as a primary raw material for the production of polycarbonate (PC) plastic and epoxy resin, widely used in a variety of common products including digital media (e.g., CDs, DVDs), electrical and electronic equipment, automobiles, sports safety equipment, reusable food and drink containers , as well as baby bottle. During the last decades, in several studies, the migration of BPA is documented to be a well-known source of food contamination. Some studies have shown that BPA, which is able to mimic the action of and hormone and to disrupt normal endocrine function, may be associated to several health problems and diseases. Recently, the European Union took a series of measures, including a ban for the import and sale PC baby bottles to reduce BPA exposure to infants. Plastic alternatives to polycarbonate have massively appeared on Belgium market. Although there are several studies on BPA migration from polycarbonate into foodstuff under a variety of conditions, there is a small amount of information about consequences on human health of the potential exposure to chemicals migrating from PC alternatives, including bottles commonly labelled “free BPA”. In a recent opinion (No. 8697, 11.03.2010), the Belgium Superior Health Council's issued its concern regarding the currently used alternatives to PC. Furthermore, they asked to investigate the possible risks associated with the use of these alternatives. In order to evaluate the safety of these alternatives, the genotoxicity and the activity on several receptors of chemical compounds migrating from PC alternatives, identified by Simoneau & al, 2012 , were evaluated using reporter gene assays. Receptor agonistic and antagonistic activities of 39 pure compounds were measured. After the first screening, certain substances clearly showed an activity on several receptors such as BPA, and Bisphenol S, while only a few substances showed no reaction on the different receptor. None of the 39 components was genotoxic as identified in the Vitotox test. However, further experiments will be performed to characterize their activity and confirm the result for the genotoxicity. [less ▲]

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See detailMultiqubit symmetric states with maximally mixed one-qubit reductions
Baguette, Dorian ULg; Bastin, Thierry ULg; Martin, John ULg

Poster (2014, November 18)

We present a comprehensive study on the remarquable properties shared by maximally entangled symmetric states of arbitrary numbers of qubits in the sense of the maximal mixedness of the one-qubit reduced ... [more ▼]

We present a comprehensive study on the remarquable properties shared by maximally entangled symmetric states of arbitrary numbers of qubits in the sense of the maximal mixedness of the one-qubit reduced density operator. Such states are of great interest in quantum information as they maximize several measures of entanglement, such as Meyer-Wallach entropy [1] and any entanglement monotone based on linear homogenous positive functions of pure state within their SLOCC classes of states [2, 3]. When they exist, they are unique up to local unitaries within their SLOCC classes [3, 4]. They play a specific role in the determination of the local unitary equivalence of multiqubit states [5]. Moreover, they are maximally fragile (in the sense that they are the states which are the most sensitive to noise) and have therefore been proposed as ideal candidates for ultrasensitive sensors [6]. They appear in the litterature under various names : maximally entangled states [6], 1-uniform states [7], normal forms [3, 4] and nongeneric states [5]. We present a general criterion to easily identify whether given symmetric states are maximally entangled or not [9]. We show that these maximally entangled symmetric (MES) states are the only symmetric states for which the expectation value of the associated collective spin S of the system vanishes, which coincides with the definition of anticoherence to order one of spin states. This definition also coincides with the cancellation of the dipole moment of the Husimi function of the state. We then generalize these properties and show that a state is anticoherent to order t, <(S.n)^k> is independent of n for k = 1, . . . , t, where n is a unit vector, iff it has maximally mixed t-qubit reductions or iff all moments up to order 2t of its Husimi function vanish. We also establish the equivalence between anticoherent states to order t and unpolarized light states to order t [8], thereby encompassing various state characterizations under the same banner [9, 10]. We provide a nonexistence criterion allowing us to know immediately whether SLOCC classes of symmetric states can contain MES states or not. We show in particular that the symmetric Dicke state SLOCC classes never contain such MES states, with the only exception of the balanced Dicke state class for even numbers of qubits. We analyze the 4-qubit system exhaustively and identify and characterize all MES states of this system as well as the only 4-qubit state anticoherent to order 2. Finally, we analyze the entanglement content of MES states with respect to the geometric [11] and barycentric [12] measures of entanglement. [1] D. A. Meyer and N. R. Wallach, J. Math. Phys. 43, 4273 (2002). [2] Classes of states equivalent through stochastic local operations with classical communication. [3] F. Verstraete, J. Dehaene, and B. De Moor, Phys. Rev. A 68, 012103 (2003). [4] G. Gour and N. Wallach, N. J. Phys. 13, 073013 (2011). [5] B. Kraus, Phys. Rev. Lett. 104, 020504 (2010). [6] N. Gisin and H. Bechmann-Pasquinucci, Phys. Lett. A 246, 1 (1998). [7] A. J. Scott, Phys. Rev. A 69, 052330 (2004). [8] L. L. Sánchez-Soto, A. B. Klimov, P. de la Hoz, and G. Leuchs J. Phys. B : At. Mol. Opt. Phys. 46, 104011 (2013). [9] D. Baguette, T. Bastin, and J. Martin, Phys. Rev. A 90, 032314 (2014). [10] O. Giraud, D. Braun, D. Baguette, T. Bastin, and J. Martin, arXiv :1409.1106. [11] T.-C. Wei and P. M. Goldbart, Phys. Rev. A 68, 042307 (2003). [12] W. Ganczarek, M. Kus, and K. Zyczkowski, Phys. Rev. A 85, 032314 (2012). [less ▲]

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See detailPRESPHOTO – a project to improve the preservation of cyanobacteria and diatom cultures
Deprez, Karolien; Vanormelingen, Pieter; Crahay, Charlotte ULg et al

Poster (2014, November 18)

The availability of biological material of guaranteed identity and quality in Biological Resource Centers is considered fundamental for scientific research and R&D, but depends heavily on adequate ... [more ▼]

The availability of biological material of guaranteed identity and quality in Biological Resource Centers is considered fundamental for scientific research and R&D, but depends heavily on adequate preservation methods. We present a new BRAIN-BE project on improving the preservation of two groups of photosynthetic microorganisms, cyanobacteria and diatoms, in two collections of the Belgian Co-ordinated Collections of Micro-organisms (BCCM). First, we will improve the cultivation success of diatoms from different habitats by testing different culture media. For organisms that keep resisting cultivation, we will develop DNA extraction and amplification, as well as morphological investigation based on single cells. Secondly, we will design and validate improved cryopreservation protocols for both diatoms and cyanobacteria, since cryopreservation is now the preferred method for the long-term storage of microalgal cultures. For that, the two-step cryopreservation method will be tested using several cryoprotectants and strains in different growth stages. Moreover, this will be compared with the encapsulation/dehydration method. For cyanobacteria, viability tests will be performed with vital dyes whereas diatoms’ survival will be assessed by PAM fluorometry. In addition, genome resequencing will be applied to determine the impact of the cryopreservation protocol(s) on genomic stability. Finally, a genomic DNA bank will be constructed and validated. This is highly complementary to preservation as living strains, given that some users require only genomic DNA and it may not be feasible to preserve the global microalgal species diversity as living cultures. [less ▲]

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See detailSpecific properties of bone marrow mesenchymal and neural crest-derived stem cells: Relevance in spinal cord injury therapy.
Neirinckx, Virginie ULg; Agirman, Gulistan ULg; Marquet, Alice ULg et al

Poster (2014, November 17)

Spinal cord injury (SCI) treatment represents a critical issue in clinical research and patient care. Stem cell-based replacement therapies have already been proposed worldwide, especially studying stem ... [more ▼]

Spinal cord injury (SCI) treatment represents a critical issue in clinical research and patient care. Stem cell-based replacement therapies have already been proposed worldwide, especially studying stem cells from the adult bone marrow stroma. Previous studies focusing on those cells did not specifically consider their intrinsic embryonic heterogeneity, thus intermingling different stem cells subpopulations to treat experimental SCI or even injured patients. In this study, we decided to compare adult bone marrow neural crest-derived stem cells (NCSC) and mesenchymal stem cells (MSC), and highlight which of their specific properties could be relevant in therapeutic perspectives. In that purpose, we compared NCSC and MSC isolated from adult mouse bone marrow. We then compared the effects that both cell types could exert once grafted inside an injured spinal cord. Cells were injected into the spinal cord of mice that right after a spinal cord contusion at the T11-12 spinal level. Our results indicate that both MSC and NCSC-injected mice recovered locomotion abilities faster than control mice (as assessed by BMS scoring). Additionally, we observed that after 28 days post-injury, the lesion volume tended to decrease in mice that received cell graft compared to control group. Interestingly, it appeared that MSC seemed to be able to modulate inflammation inside the lesion, more than NCSC. Indeed, MSC-graft increased early neutrophil and macrophage recruitment in the bloodstream and inside the spinal cord, and increased the number of arginase-1-expressing cells remaining in the spinal cord after 28 days. In parallel, we compared the secretome of both NCSC and MSC, and noticed some interesting differences: MSC secreted several chemokines reflecting possible immunomodulating properties, while NCSC secreted products might be able to enhance neurite outgrowth. Indeed, preliminary data showed that NCSC induced neuritogenesis on primary neurons in vitro. Altogether, those results should help to improve and optimize cell-based therapies parameters and/or to define precise and efficient pharmacological treatments for SCI patients. [less ▲]

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See detailGlutamate controls brain estrogen synthesis during sexual interactions
de Bournonville, Catherine ULg; Aourz, Najat; Van Eeckhaut, Ann et al

Poster (2014, November 17)

Besides their long-lasting effects mediated by a modulation of gene transcription, brain-derived estrogens can rapidly regulate (within minutes) reproductive behaviors. In vitro, the activity of aromatase ... [more ▼]

Besides their long-lasting effects mediated by a modulation of gene transcription, brain-derived estrogens can rapidly regulate (within minutes) reproductive behaviors. In vitro, the activity of aromatase (AA), the enzyme responsible for the conversion of androgens into estrogens, is also regulated on a similar short time-scale, via phosphorylation of the enzyme resulting from changes in neuronal activity or glutamate release. Acute changes in AA have been documented ex vivo in specific brain regions following exposure to social or stressful stimuli but the mechanism underlying these regulations is not known. To investigate whether glutamate is implicated in these rapid changes in AA, male quail received a unilateral injection of kainate in the medial preoptic nucleus (POM). The left and right preoptic areas were collected 20 min later and assayed separately by the tritiated water technique for AA. As shown previously in preoptic explants maintained in vitro, AA was downregulated in the kainate-injected hemisphere as compared to the non-injected side. To determine whether the decline in AA detected in the POM after a sexual interaction could be mediated by an increased release of glutamate in this region, extracellular glutamate concentration was measured by in vivo microdialysis with a probe implanted in the POM of sexually mature males. Dialysate was collected every 3 minutes over three periods of 15 min when the male was (1) alone, (2) allowed to freely copulate with a female and (3) alone again. A transient rise in extracellular glutamate concentration was observed specifically and immediately after the expression of cloacal contact movements, when semen is transferred to the female. Glutamate returned to a basal level after the female was removed. Together, these results indicate that the mechanism of acute regulation of aromatase activity by glutamate identified in vitro is potentially responsible for the acute regulation of the enzyme observed in vivo following copulation. As rapid changes in brain estrogen synthesis and its actions are apparently related to the control of sexual motivation rather than sexual performance, follow up experiments should now determine whether the release of glutamate in the POM occurs in parallel with an increase in motivation or follows the termination of the copulatory sequence. [less ▲]

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See detailGNSS observational bias in the frame of ionospheric studies
Wautelet, Gilles ULg; Warnant, René ULg

Poster (2014, November 17)

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See detailContrasting the role of Ih and ICaT currents in post-inhibitory rebound mechanisms in reciprocal-inhibitory networks
Dethier, Julie ULg; Drion, Guillaume ULg; Sepulchre, Rodolphe

Poster (2014, November 16)

Models with reciprocal inhibition are ubiquitous in the literature. For instance, common rhythmic motor behaviors produced by central pattern generators (CPGs) involve half-center oscillators, which ... [more ▼]

Models with reciprocal inhibition are ubiquitous in the literature. For instance, common rhythmic motor behaviors produced by central pattern generators (CPGs) involve half-center oscillators, which consist of two inhibitory neurons that are not endogenous oscillators, but produce rhythmic outputs when reciprocally connected (Marder & Calabrese 1996). Models of thalamocortical spindle oscillations also suggest that the rhythm originates from the thalamic reticular nucleus, which consists in interacting inhibitory nonoscillatory neurons (Wang & Rinzel 1992). [less ▲]

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See detailEffect of “diagnosis threat” in clinical setting
Fresson, Megan ULg; Dardenne, Benoît ULg; Meulemans, Thierry ULg

Poster (2014, November 14)

Objective. When reminded of their neurological history, mild traumatic brain injured (TBI) students underperform on neuropsychological tests (Suhr & Gunstad, 2002). To date, this “diagnosis threat” (DT ... [more ▼]

Objective. When reminded of their neurological history, mild traumatic brain injured (TBI) students underperform on neuropsychological tests (Suhr & Gunstad, 2002). To date, this “diagnosis threat” (DT) phenomenon has mainly been studied with a non-clinical and high-functioning population (university students). The aim of this study was twofold: to study this phenomenon with neurological patients and to examine the mechanisms responsible for underperformance. Method. Patients (18-55 years-old) who had sustained a TBI or a stroke were recruited from ambulatory and hospitalized cares, and then assigned to one of three conditions : Patients attention was drawn on (1) their neurological disease and the neuropsychological components of the upcoming tasks (DT group) ; (2) their intact sensory capacities and the sensorial components of the tasks (Neutral group); or (3) their better cognitive abilities compared to Alzheimer disease patients (Stereotype boost group). After these instructions, patients carried out cognitive tasks and completed questionnaires. Results. Preliminary analyses (n=18) showed that, on the z-score of executive functioning, the DT group performed worse than both the neutral group (p=.03) and the stereotype boost group (p=.05), but did not differ for the attentional and memory scores. Instructions also had an impact on cognitive self-efficacy, with the neutral group demonstrating greater score than the negative one (p=.08). Furthermore, the self-efficacy score tended to correlate with the score of executive functioning (r=.37). Conclusions. Results show that the DT phenomenon has an impact on cognitive performances in clinical setting, at least on executive functions, which are usually demonstrated to be the most sensitive to stereotype effects. [less ▲]

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See detailEconomic efficiency of milk production farms in Hanoi Suburbs, Vietnam
Le Dinh, Khan; Phan Dang, Thang ULg; Lebailly, Philippe ULg et al

Poster (2014, November 14)

Dairy production has presented in Vietnam since 50 years, but these dairy farms really developed from 2001. In the period 2001 – 2010, the average growth rate of dairy herds was up to 30% per year ... [more ▼]

Dairy production has presented in Vietnam since 50 years, but these dairy farms really developed from 2001. In the period 2001 – 2010, the average growth rate of dairy herds was up to 30% per year. However, fresh milk production satisfies about 20-25% of milk consumption. The rural areas of Hanoi Province are large for dairy production. This province builds the 7 agro-ecological sub-regions for the development of dairy farming, in which Ba Vi District is a most of sub-regions for dairy production development. But the average size is about 2.5 cows per farm. This research aims to better understand how the factors in milk sector adapt to current economic conditions in Hanoi suburbs through analyzing farming systems. These studies were conducted from January to August 2012 on 43 dairy farms with different production scales at Ba Vi District to characteristic of dairy farming systems. The data were collected by interviewing and keeping records at the farms that have milk production. The results showed that three dairy production systems in these zones: (1) Dairy small farming system has from 1 to 3 cows per farm; (2) The medium farming system has from 4 to 5 cows per farm; and (3) The dairy intensive farming system has more 5 cows per farm. The economic activities were really diversified with landless per household farm such as rice production, gardens, grass production and sylviculture. Land resources per farm of intensive farming system were largest including 9,239 m² for garden around the household; 2,574 m² for rice land; 563 m² of grass area and 3,325 m² for sylviculture. While the small farming system has the lowest potential land, each household has only 2,815 m² of garden; 1,795 m² of rice land; 2,095 m² of grazing land. The medium farming system has about 3,150 m² of garden; 2,220 m² of rice land and 3,891 m² of grazing land. Milk production cycle was quite long with intensive farming system, up to 324 days comparing with 299 days per cycle with medium farming system and to 306 days per cycle with small-scale farmers. This difference was not statistically signification (P> 0.05). Average milk production yield per cow was high with medium farming system (16 kg per cow per day) in comparison with 15 kg per day at intensive and small farming systems (P> 0.05). Milk production yield has been improved in the past years with crossbreed cows such as Holstein-Friesian 50% and 75%. But this productivity was still considered to be lower than the milk production yield with dairy cows raised in Moc Chau District under Son La Province with 20.5 kg per cow per day and 6,250 kg of milk per cow per cycle). In addition, in the period from 2006 to 2012, fresh milk prices at farm gate have continued to rise for the farmers, while feed prices increased in the period from 2006 to 2010 and these feed prices were stable between 2011 and 2012. In the period of 2006 to 2012, fresh milk prices at farm gate increased from 0.17 USD per kg in 2006 to 0.60 USD per kg in 2012 and feed prices were from 0.15 USD per kg in 2006 increasing to 0.39 USD per kg in 2012. The net incomes were calculated per a cow per year reached 1,274 USD with the small-scale farming households to 1,476 USD with medium farming system. The net income per kg of fresh milk at farm gate obtained from 0.28 USD with small farming system to 0.31 USD with medium farming system. The net household income was high from dairy production, from 2,437 USD per farm per year with small farming system to 5,487 USD per farm per year with intensive farming system. The net labor family income gained from 997 USD per active per year with small farming system to 2,757 USD per active per year with intensive farming system. Thus, dairy production farms in recent years in Hanoi Suburbs provide very high economic efficiency for farmers in comparison with other agricultural activities at the farms. This explains why the rate of dairy family farming has grown very fast in the studied zones in the period from 2009 to 2012. This trend will continue to grow in the future. This research was also showed that the price of fresh milk plays a crucial role for profitable at farm level. But medium farming system with the size from 4 to 5 dairy cows per farm is more profitable with current economic conditions at farms. [less ▲]

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See detailIs there a global procedural learning deficit in children with Specific Language Impairment ?
Desmottes, Lise ULg; Maillart, Christelle ULg; Lejoly, Kelly ULg et al

Poster (2014, November 13)

The study of procedural learning abilities in children with Specific Language Impairment (Procedural Deficit Hypothesis, PDH; Ullman & Pierpont, 2005) remains a relatively unexplored field of research ... [more ▼]

The study of procedural learning abilities in children with Specific Language Impairment (Procedural Deficit Hypothesis, PDH; Ullman & Pierpont, 2005) remains a relatively unexplored field of research. Since most evidence comes from studies using tasks which involve learning of sequenced patterns, research using other procedural learning paradigms (like motor adaptation tasks) is needed to further evaluate the PDH in children with Specific Language Impairment (SLI). Therefore, in this study, we examined the ability of children with and without SLI to learn, consolidate and generalize a mirror-tracing task, a paradigm that does not involve sequence learning and had never been used in SLI. Children with SLI and typical developing (TD) matched children participated in the study. Children with SLI were included if they scored below -1.25 SD of the expected normative performance in at least 2 language areas. Both groups had to trace ten 5-pointed stars seen only in mirror-reversed view in two learning sessions separated by a one-week delay. The transfer phase consisted in tracing a new figure. The time required to complete the tracing, and the number of errors committed were recorded. Full results will be presented and discussed during the presentation of the paper. [less ▲]

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See detailWhen food cultures meet. Ethnographic analysis of belongings and positionings.
Mescoli, Elsa ULg

Poster (2014, November 13)

The displacement of human beings is always accompanied by the movement of things and practices which travel with them. This is an obvious statement that indeed leads to interesting studies on the material ... [more ▼]

The displacement of human beings is always accompanied by the movement of things and practices which travel with them. This is an obvious statement that indeed leads to interesting studies on the material culture involved by people’s mobility. Within this culture are food habits, objects of numerous scholars’ researches often focusing on culinary changes (or resistances) linked to migration paths. Far for being the only issue at stake when studying migrant’s food practices – moreover frequently assumed as originally static prior to migration –, this matter is likely to overshadow other significant dynamics. Such as those which occur when supposedly different food cultures meet, thus leading to the mobilization of belongings by groups who want to take a specific position toward one another. My paper is aimed at analysing this encounter. The assumption is that it shapes a space which corresponds to a tertium quid, that is a dimension where not only the boundaries of food cultures fade, proving of an original indeterminacy and interchangeability of practices, but also where individuals constantly change their reciprocal position depending on the perspective of the gaze upon them. To show these dynamics, I will present the ethnographic data stemmed from my doctoral research about the culinary practices of a group of Moroccan migrant women living in Milan hinterland. I will support my presentation with visual materials collected during an eighteen month fieldwork which included observations and interviews inside homes as well as in public events such as an Arab cooking class. [less ▲]

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See detailInfluence de la vitesse de croissance sur le classement de lames de bardage de Douglas wallon (Belgique)
Pollet, Caroline; Henin, Jean-Marc; Hebert, Jacques ULg et al

Poster (2014, November 12)

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See detailRecyclable shape-memory materials based on photo or thermo-reversible crosslinking
Defize, Thomas ULg; Riva, Raphaël ULg; Wauters, Céline et al

Poster (2014, November 11)

Shape memory polymers (SMPs) are remarkable materials able to switch from a stressed deformed state (temporary shape) to their initial relaxed state (permanent shape) by the application of a stimulus ... [more ▼]

Shape memory polymers (SMPs) are remarkable materials able to switch from a stressed deformed state (temporary shape) to their initial relaxed state (permanent shape) by the application of a stimulus, such as heat or light. Typically, the shape memory property is generally observed for chemically or physically cross-linked polymers that exhibit an elastomeric behavior above a phase transition, e.g. glass or melting transition. Cross-linked semi-crystalline poly(ε-caprolactone) (PCL) is already widely studied for the development of SMPs. However, the tensile strength of standard PCL-based SMPs remains quite low, limiting their use in some applications. A convenient way to enhance the strength of SMPs relies on the introduction of nanofillers, such as silica nanoparticles, leading to an enhancement of mechanical strength. Moreover, silica nanoparticles can be advantageously used as multifunctional crosslinking nodes, with the purpose to increase the cross-linking density of the material. As most of SMPs are irreversibly cross-linked material, their reprocessing is impossible preventing any recycling. Thereby, reversible reactions, allowing the formation/cleavage of the network, raise tremendous interest in macromolecular engineering. Recently, a reversibly cross-linked 4-arm star-shaped PCL-based SMP was prepared using the Diels-Alder (DA) reaction between furan and maleimide moieties, well-known to create reversible bonds. This shape memory material demonstrated to be implementable, and so recyclable, and was characterized by excellent fixity and recovery before and after recycling experiments. However, the relatively low retro-DA temperature of the furan- maleimide adducts led to an inelastic deformation during shape memory tensile cycles. In order to get rid of this drawback, two alternative approaches were investigated. Firstly, the substitution of the DA reaction by a photo-reversible reaction, typically the photo- induced (2+2) cycloaddition of coumarins, was proposed to crosslink the PCL matrix. The second approach is based on the use of surface functionalized silica nanoparticles as crosslinking nodes with the purpose to increase the crosslinking density of the material. The network formation and cleavage were studied by solid-state NMR and rheology.4 The resulting shape memory materials were characterized by excellent one-way and two-way shape memory properties as demonstrated by dynamical mechanical analysis. [less ▲]

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See detailUse of lipid probes as matrices for MALDI Imaging applications
Longuespée, Rémi ULg; Alberts, Deborah ULg; Pottier, Charles et al

Poster (2014, November 07)

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See detailDevelopment of a high throughput de novo sequencing platform for peptidic toxins combining proteomics and transcriptomics
Degueldre, Michel ULg; Verdenaud, Marion; Zuniga, Sheila et al

Poster (2014, November 07)

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See detailComparison of Life cycle Impact Assessment methods in a case of crop in Northern France
Merchan, Angel ULg; Combelles, Agathe

Poster (2014, November 05)

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See detailDisentangling the sources of phenotypic variation in Ambrosia artemisiifolia L.: the role of seed traits
Ortmans, William ULg; Monty, Arnaud ULg; Mahy, Grégory ULg

Poster (2014, November 03)

When invading new environments, a plant invader may express new phenotypes as a result of different ecological and genetic processes. It includes phenotypic plasticity, local adaptation, environmental ... [more ▼]

When invading new environments, a plant invader may express new phenotypes as a result of different ecological and genetic processes. It includes phenotypic plasticity, local adaptation, environmental maternal effects, and genetic drift. The quantification of each of these factors is crucial in the study of biological invasions. Ambrosia artemisiifolia L. invasion success is strongly linked to seed characteristics (dispersal by human activities, long-lived soil seed bank, etc.). Known as an opportunist and a colonizer, the species is often limited by the competition from other plants. In the early stages of development, the seedlings can be quickly outcompeted and a rapid growth is therefore a major advantage. First, this study aims to analyze the seed traits variation, and to detect an impact of these traits on the early development of the seedling (environmental maternal effect). Second, we aimed to quantify the respective role of phenotypic plasticity, environmental maternal effect, local adaptation and genetic drift on seedlings phenotype. Variability of seeds from 3 geographical zones (Belgium – Centre of France – South of France) was assessed. We measured the seed variation in mass, length, width, circularity, and pigmentation. Seeds were disposed in growth chamber under two temperature treatments. After two months, we compared seedling phenotypic variation in germination time, height, aboveground biomass, belowground biomass, early competitive performance, and the final leaf area. We found a high variability of seed traits. Seeds were varying significantly among zones, populations, and parents, with more than 30% of the variation attributable to the mother plant identity. The main sources of seedling phenotypic variation appeared to be phenotypic plasticity and environmental maternal effect. No genetic differentiation was detected in this study. Seed mass was positively correlated to seedling biomass, early competitive performance, and the final leaf area. The relevance of traits reflecting environmental maternal effect is discussed. Phenotypic plasticity and seed characteristics appear to play a major role in the invasion success. [less ▲]

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See detailAnalysing spatiotemporal changes in sediment contamination
Richir, Jonathan ULg; Pini, Jennifer; White, Shannon et al

Poster (2014, November)

Coastal environments are subjected to anthropogenic threats, of which pollution by trace elements (TEs). They remain chemicals of concern because of their toxicity, their ability to be concentrated in ... [more ▼]

Coastal environments are subjected to anthropogenic threats, of which pollution by trace elements (TEs). They remain chemicals of concern because of their toxicity, their ability to be concentrated in biota and their persistence in sediment. Aware of these threats, monitoring agencies perform large environmental surveys. However, the databases generated often remain underexploited, even though they represent an important source of information for scientists. As a case study, we focused on the highly industrialized and developed coastal area of the Solent, south coast of the UK, which is also a European Marine site with protected habitats and species. To date, no scientific-based spatiotemporal trend has been published regarding its pollution in TEs. But mining of existing databases requested from the Environmental Agency and the Marine Environment Monitoring and Assessment National database showed that sediment from 32 sites were/are indeed monitored for that purpose, covering a 22 years period (1992-2013). Temporal trend analysis showed that sediment contamination significantly decreased during that time interval (45 % decrease in median). However, all TEs still show concentrations above Sediment Quality Guidelines. Important spatial variability is also present, presumably linked to the distribution of pollutant anthropogenic sources. Taken together, these data have been used to provide stakeholders with relevant scientific based tools, i.e. GIS maps of the contamination in TEs in the Solent. This regional-level assessment enables local stakeholders to create bridges between environmental scientists and local authorities and valorizes the existing databases, for future governance at the regional and national scales. [less ▲]

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See detailDifferent activities of chemokines CXCL12 and vCCL2 and peptides derived from their N-terminus towards the receptors CXCR7/ACKR3 and CXCR4
Szpakowska, Martyna ULg; Gauthier, Pierre-Arnaud; Derj, Anouar et al

Poster (2014, November)

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See detailImpact de la phéromone d’alarme sur l’efficacité de la transmission de virus
Bosquée, Emilie ULg; Lin, Fang Jing; Liu, Ying Jie et al

Poster (2014, November)

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See detailTMS can selectively activate and condition two different sets of excitatory synaptic inputs to corticospinal neurons in humans
Sommer, Martin; D'Ostilio, Kevin ULg; Cioccia, Matteo et al

Poster (2014, November)

Background: Current protocols or repetitive transcranial magnetic stimulation (rTMS) induce mixed facilitatory and inhibitory effects. More selective, quasi-monophasic high-frequency stimulators now ... [more ▼]

Background: Current protocols or repetitive transcranial magnetic stimulation (rTMS) induce mixed facilitatory and inhibitory effects. More selective, quasi-monophasic high-frequency stimulators now become available. We sought to investigate the impact of current direction and pulse width on intermittent theta burst stimulation (iTBS) effects on human motor cortex excitability. Also, we estimated strength-duration time constants from motor threshold and input-output (IO) curves for PA and AP orientations. Methods: We stimulated the dominant hand representation of the motor cortex in 15 healthy subjects, using “unidirectional biphasic” pulses generated by a controllable TMS machine (cTMS-3, Rogue Resolutions Ltd., Cardiff, UK), connected to a standard figure-8 coil. iTBS was applied conventionally, using 20 sequences of 2 seconds iTBS (10 bursts at 5 Hz burst repetition frequency, each burst consisting of 3 pulses of 80 % AMT intensity repeated at 50 Hz frequency). In separate sessions pulses differing in current direction and shape were applied: a) posterio-anterior (PA) current direction in the brain, 75 μs (iTBS_PA75). b) AP current direction, 45 μs (iTBS_AP45). Before and for 30 minutes after iTBS, we monitored the modulation of motor evoked potential (MEP) amplitude from the dominant first dorsal interosseus using conventional, monophasic, suprathreshold pulses generated by a Magstim 2002 stimulator, inducing PA currents in the brain, at 0.2 Hz frequency. In an additional study on ten healthy subjects, we investigated the effect the two coil orientations with three different pulse widths (30, 60 and 120 μs) on the IO curve and the latency of the motor evoked potentials (MEPs). Results: iTBS_AP45 yielded a pronounced and slightly delayed inhibition of MEP amplitude in all but one subjects, it was unrelated to the MEP latency differences. iTBS_PA75 had a variable and inconsistent effect that was in part related to the latency differenceAP-LM , in that long latency differences were correlated with the induction of inhibition rather than facilitation. We found a longer time constant for AP than PA orientation. MEP latencies yielded an interaction between pulse width and orientation, due mainly to longer onset latencies following AP stimuli of short duration. Conclusions: Current direction influences the outcome of iTBS, with a preference for AP currents. PA and AP stimuli activate the axons of neurones with different time constants. Those activated by AP pulses excite corticospinal outputs with a longer latency than those activated by PA pulses. AP pulses of short duration recruit long latency inputs most selectively. [less ▲]

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See detailTreg/Th17 balance during murine embryo implantation and pregnancy
Polese, Barbara ULg; Gridelet, Virginie ULg; Araklioti, Eleni et al

Poster (2014, November)

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See detailAmmonia oxidizing bacteria community structure and richness under coniferous/deciduous tree species at three temperate forest sites
Malchair, Sandrine ULg

Poster (2014, November)

Ammonia Oxidizing Bacteria community structure and richness under coniferous/deciduous tree species at three temperate forest sites Malchair S. and Carnol M. Laboratory of Plant and Microbial Ecology ... [more ▼]

Ammonia Oxidizing Bacteria community structure and richness under coniferous/deciduous tree species at three temperate forest sites Malchair S. and Carnol M. Laboratory of Plant and Microbial Ecology Department Biology, Ecology and Evolution University of Liege, Belgium Introduction: Despite the crucial roles of soil microorganisms in ecosystem processes, numerous uncertainties subsist on the relationship between soil microbial diversity and function. Furthermore, the link between aboveground and belowground diversity remains also unclear. In European forests, at the beginning of the 19th century, plantations of Norway spruce and Scots pine for timber production were substantially increased. However, concerns were expressed with regard to the ecological risks posed by coniferous monocultures. The conversion of these monocultures into broadleaved or mixed stands has been suggested as a solution. Nevertheless, belowground effects of such a change in the dominant tree species is largely unknown, although bacteria regulate many soil processes and some groups, like ammonia oxidizing bacteria (AOB) are highly sensitive to environmental stresses. Objectives: The aims of this study were to investigate (i) AOB community structure and richness under several tree species, (ii) microbial/environmental factors influencing AOB diversity, (iii) the relationship between AOB diversity and the nitrification process. Materials and methods: Forest floor (Of, Oh) was sampled under Norway spruce, Douglas fir, European beech and sessile oak at three temperate forest sites. AOB diversity (community structure and richness) was assessed by PCR-DGGE and sequencing. Samples were analysed for microbial (net N mineralization, potential nitrification, basal respiration, microbial biomass, microbial or metabolic quotient) and environmental parameters (pH, total nitrogen, extractable ammonium, organic matter content and exchangeable cations). Results: AOB sequences retrieved in this study were related to different uncultured strains from soils, related to both Nitrosospira-like and Nitrosomonas-like sequences. AOB community structure and tree species effects on AOB diversity were site-specific. AOB community structure was influenced by environmental/microbial parameters, i.e. net N mineralization or organic matter content, regulating ammonium availability. AOB richness was not related to nitrification but a very weak correlation between potential nitrification and AOB community structure was observed. Conclusions: At larger spatial scales, site specific characteristics may be more important that tree species in determining AOB richness and community structure. However, within sites, tree species influence AOB diversity. The absence of a clear relationship between AOB diversity and nitrification points to a possibly role of AOB abundance, phenotypic plasticity or the implication of ammonia oxidizing archaea in this process. [less ▲]

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See detailSystematic Analysis of two cystatin C assays using samples of 2057 older adults - The Berlin initiative study
Ebert, natalie; DELANAYE, Pierre ULg; Martus, Peter et al

Poster (2014, November)

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See detailDistribution and robustness of a distance-based multivariate coefficient of variation
Aerts, Stéphanie ULg

Poster (2014, November)

When one wants to compare the homogeneity of a characteristic in several popula- tions that have di erent means, the advocated statistic is the univariate coe cient of variation. However, in the ... [more ▼]

When one wants to compare the homogeneity of a characteristic in several popula- tions that have di erent means, the advocated statistic is the univariate coe cient of variation. However, in the multivariate setting, comparing marginal coe cients may be inconclusive. Therefore, several extensions that summarize multivariate relative dispersion in one single in- dex have been proposed in the literature (see Albert & Zhang, 2010, for a review). In this poster, focus is on a particular extension, due to Voinov & Nikulin (1996), based on the Mahalanobis distance between the mean and the origin of the design space. Some arguments are outlined for justifying this choice. Then, properties of its sample version under elliptical symmetry are discussed. Under normality, this estimator is shown to be biased at nite samples. In order to overcome this drawback, two bias corrections are proposed. Moreover, the empirical estimator also su ers from a lack of robustness, which is illustrated by means of in uence functions. A robust counterpart based on the Minimum Covariance Determinant estimator is advocated. [less ▲]

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See detailAnalyse à haute résolution spatiale et temporelle des activités humaines à l’Holocène récent dans les forêts humides d’Afrique Centrale
Morin, Julie ULg; Gorel, Anaïs ULg; Biwolé, Achille et al

Poster (2014, November)

Des études paléoécologiques et archéologiques ont démontré que les populations humaines ont de longue date investi les forêts humides d’Afrique Centrale. Les occupations humaines ont toutefois été peu ... [more ▼]

Des études paléoécologiques et archéologiques ont démontré que les populations humaines ont de longue date investi les forêts humides d’Afrique Centrale. Les occupations humaines ont toutefois été peu documentées en raison de difficultés relatives à l’accès au terrain. Nous présentons ici une méthodologie systématique basée sur la quantification et la datation des macrorestes botaniques carbonisés pour définir les activités humaines passées en forêt tropicale africaine. Pour cela, 53 sondages équidistants ont été creusés dans 3 sites du sud-est-du Cameroun. Dans chaque sondage ont été prélevées des quantités fixes de sol par couche de 10 cm. Les macrorestes botaniques carbonisés ont été récoltés par tamisage à l’eau directement sur le site. Les refus de tamis ont été triés (charbons de bois, endocarpes de palmier à huile, graines non identifiées), pesés sur une balance de précision et analysés statistiquement. En outre, 25 échantillons ont été datés par AMS. Les résultats montrent que les activités humaines sont réparties en deux périodes : l’âge du Fer ancien entre 2300 et 1300 BP et l’âge du Fer récent entre 670 BP et l’actuel. En outre, les charbons de bois et les endocarpes de palmier à huile ne représentent pas le même type d’activités. Deux villages âge du Fer ancien datés d’environ 2000 BP ont été identifiés par la présence concomitante d’endocarpes de palmier à huile et de tessons céramiques. Les motifs circulaires imprimés dans la céramique et inédits pour la zone d’étude rappellent les gravures et décors céramiques découverts au Gabon et dans la zone de la Sangha-Likwala-aux-Herbes, datés également de 2000 BP. L’abondance décroissante des charbons dans l’orbe d’influence de ces villages pourrait correspondre à d’anciennes zones agricoles. Les perturbations les plus récentes peuvent, quant à elles, être mises en relation avec la végétation actuelle, en particulier les arbres émergents héliophiles qui dominent la composition floristique et qui sont des recrus post-culturaux. Pour la première fois, une méthodologie quantitative basée sur les restes archéobotaniques a été appliquée en Afrique Centrale. Elle nous a permis de documenter à haute résolution la répartition spatiale et temporelle des activités humaines à l’échelle locale. Ce travail sera poursuivi par une reconstitution paléoenvironnementale à partir de l’identification des macrorestes végétaux. [less ▲]

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See detailRobust detection of local outliers in multivariate spatial data
Ernst, Marie ULg

Poster (2014, November)

Multivariate spatial data are geographical locations on which non spatial variables are measured. Such data may contain two types of outliers: global and/or local. Focus is here on local outlier whose ... [more ▼]

Multivariate spatial data are geographical locations on which non spatial variables are measured. Such data may contain two types of outliers: global and/or local. Focus is here on local outlier whose attribute values lie far from the values taken by its neighbors. This poster has three main objectives. The first is to review some local detection techniques that seem to perform well in practice. Secondly, an adaptation to one of these is suggested to further develop its local characteristic. Then simulations based on Matérn model are reported and discussed in order to compare in an objective way the different detection techniques. [less ▲]

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See detailMicrowave-assisted extraction of pectin from unused pumpkin biomass
Košťálová, Zuzana; Aguedo, Mario ULg; Hromádková, Zdenka

Poster (2014, November)

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See detailHighly sophisticated compound droplets on fiber arrays
Weyer, Floriane ULg; Lismont, Marjorie ULg; Dreesen, Laurent ULg et al

Poster (2014, November)

The poster shows a drop of oil containing four soapy water droplets of four different colors : red, orange, green and blue. This sophisticated object is created thanks to a fiber array. Fiber networks ... [more ▼]

The poster shows a drop of oil containing four soapy water droplets of four different colors : red, orange, green and blue. This sophisticated object is created thanks to a fiber array. Fiber networks allow processes such as droplet motion, fragmentation, trapping, releasing, mixing and encapsulation. Therefore, by using a vertical fiber decorated with successive nodes, compound droplets can be created. A soapy water droplet, with a specific color, is placed at each intersection. Then, a silicon oil droplet glides along the vertical fiber, encapsulates and collects the water droplets at each node leading to the formation of a compound droplet with four different components. [less ▲]

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See detailEtude de la forme d'arcade dentaire après nivellement en technique Damon.
LEWY, Stéphanie; LIMME, Michel ULg; BRUWIER, Annick ULg

Poster (2014, November)

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See detailMagnetospheric modes and magnetic reconnection.
Hubert, Benoît ULg; Milan, S.E.; Cowley, S.W.H.

Poster (2014, November)

We combine imaging of the proton aurora from the SI12-IMAGE instrument with measurement of the ionospheric convection from the SuperDARN radar network to analyze the cycle of magnetic flux opening and ... [more ▼]

We combine imaging of the proton aurora from the SI12-IMAGE instrument with measurement of the ionospheric convection from the SuperDARN radar network to analyze the cycle of magnetic flux opening and closure of the Earth magnetosphere. Interaction between the solar wind and the Earth geomagnetic environment causes a reconfiguration of the magnetic field that connects the interplanetary magnetic field (IMF) to the geomagnetic field. This reconnection process produces open magnetic field lines (i.e. field lines of the magnetosphere that close through the interplanetary medium) that are dragged to the magnetotail by the solar wind flow, where they eventually reconnect again, back to a closed topology. The SI12 imaging of the Doppler-shifted Lyman-α emission of the proton aurora is used to estimate the location of the boundary separating open and closed field lines at ionospheric altitude. We then estimate the open magnetic flux of the Earth magnetosphere, encircled by this boundary. The rate of reconnection causing a variation of the open magnetic flux can be expressed as a voltage in application of Faraday’s law. This voltage is measured along the open/closed field line boundary determined from the imaging data. The electric field associated with the voltage has two origins: motion of the boundary and the ionospheric field. We use the ionospheric electric field deduced from ionospheric convection measurement from the SuperDARN to estimate the reconnection voltage at the magnetopause (flux opening) and in the magnetotail (flux closure) accounting for the motion of the open/closed field line boundary determined from the SI12 images. The method is applied during substorms, steady geomagnetic convection intervals, sawtooth events and geomagnetic storms. These different intervals are characterized by different values of open flux and reconnection rates, as a result of different coupling between the solar wind and the geomagnetic environment. We interpret these differences as different dynamic modes of the magnetospheric system. Shock-induced flux closure events are also presented, as an exceptional situation that differs from the modes presented above. [less ▲]

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See detailCaractérisation de bois utilisés dans la construction de quatre xylophones africains à résonateurs
Warneke, Nikolaus; Houssay, Anne; Morin, Julie ULg et al

Poster (2014, November)

Nous avons besoin de collaborations avec des anatomistes pour travailler avec nous sur des méthodes d’identification des bois si possible sans ou avec le minimum de prélèvement. Notre microscope in ... [more ▼]

Nous avons besoin de collaborations avec des anatomistes pour travailler avec nous sur des méthodes d’identification des bois si possible sans ou avec le minimum de prélèvement. Notre microscope in situ facilite l’étude des collections. En cherchant à caractériser les essences de bois utilisées pour la fabrication d’instruments de musique traditionnels en Afrique, le choix du bois peut meAre en évidence la disponibilité de telle ou telle essence à un moment précis, et son apprécia1on du point de vue des musiciens. La façon de tailler les lames peut montrer des échanges culturels et techniques ou au contraire des pratiques spécifiques. L’étude des accords peut donner des échelles musicales communes ou au contraire distinctes. La richesse des timbres produits suivant ces choix peut être un élément culturel, technique et esthétique. Patrimoine naturel et musical sont ainsi mis en relation. [less ▲]

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See detailIon mobility-mass spectrometry to perform structural classifications of disulfide-bridged-peptides
Massonnet, Philippe ULg; Upert, Gregory; Morsa, Denis ULg et al

Poster (2014, November)

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See detailTh17 cells in melanoma microenvironment
Weatherspoon, Alodie ULg; Multon, Sylvie ULg; Defaweux, Valérie ULg et al

Poster (2014, November)

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See detailImpact of the dialysis membrane on the Vitamin D metabolims markers
CAVALIER, Etienne ULg; DUBOIS, Bernard ULg; Urena, Pablo et al

Poster (2014, November)

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See detailComputergestützte Förderung der mündlichen Leistung im Fremdsprachenunterricht - Die @lter Fremdsprachkurse an der Universität Lüttich (ULg), Belgien
Thonard, Audrey ULg; Jérôme, Françoise ULg; Badir, Yasmine ULg et al

Poster (2014, October 30)

The poster présents the implementation of voice tools in the service of foreign language learning at the University of Liège. Oral skills (comprehension and production) are trained online in autonomy and ... [more ▼]

The poster présents the implementation of voice tools in the service of foreign language learning at the University of Liège. Oral skills (comprehension and production) are trained online in autonomy and with instructors' interventions. The setting also provides facilities for oral feedbacks. [less ▲]

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See detailRecyclage des briques cassées pour améliorer les propriétés céramiques des argiles plastiques (Meknès, Maroc)
El Ouahabi, Meriam ULg; Daoudi, Lahcen; El Boudour El Idrissi, Hicham ULg et al

Poster (2014, October 27)

Dans le Bassin de Saïs (nord ouest du Maroc), les argiles du Miocène de la région de Meknès sont utilisées dans l’industrie céramique locale pour la fabrication des briques. Ces argiles riches en smectite ... [more ▼]

Dans le Bassin de Saïs (nord ouest du Maroc), les argiles du Miocène de la région de Meknès sont utilisées dans l’industrie céramique locale pour la fabrication des briques. Ces argiles riches en smectite et en carbonates, ont une granulométrie très fine, marquée par la quasi absence de la fraction sableuse. Ces propriétés les rendent très plastiques, ce qui engendre des taux de retrait importants au séchage et à la cuisson et des problèmes de qualité du produit fini qui s’en suivent (fissurations, déformations et casses pendant les processus de séchage et de cuisson). Dans le but de palier à ce problème et d’améliorer la qualité du produit fini, nous proposons au cours de cette étude de recycler les déchets de briques cassées. Afin d'atteindre ces objectifs, 4 formulations ont été réalisées à base d’argiles plastiques, riches en smectite et des casses de briques broyées. Des quantités de 5, 10, 15 et 20% de briques broyées ont été ajoutées à la pâte destinée à la confection des briques. Des analyses minéralogiques par diffraction des rayons X (DRX), chimiques par spectrométrie de fluorescence (XRF), granulométrique par granulométrie laser, ainsi que les limites d’Atterberg ont été effectuées. Les résultats minéralogiques montrent une diminution de la teneur en carbonates (calcite) et en argile totale (principalement smectite), lors des ajouts successifs de briques broyées. La fraction sableuse augmente progressivement, jusqu’à atteindre 30% pour une formulation avec 20% de casses de briques. Cette granulométrie plus grossière diminue la plasticité de la pâte et permet d’éviter les déformations et les fissures pendant le processus du séchage. De plus, l’ajout des casses de briques dilue les carbonates, ce qui permet d’améliorer la qualité du produit cuit. Ces résultats indiquent que le recyclage des déchets de briques, présente un intérêt à la fois économique et écologique. Des essais de comportement au séchage et à la cuisson ainsi que des essais mécaniques complèteront cette étude. [less ▲]

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See detailReformage catalytique du toluène
Claude, Vincent ULg; Lambert, Stéphanie ULg; Courson, Claire

Poster (2014, October 23)

This poster summarizes results obtained for the catalytic reforming of tar in the oultlet gas of a biomass gasifier. All samples were synthesized with aluminum nitrate and an organosilane (EDAS) in order ... [more ▼]

This poster summarizes results obtained for the catalytic reforming of tar in the oultlet gas of a biomass gasifier. All samples were synthesized with aluminum nitrate and an organosilane (EDAS) in order to enhance the metallic dispersion and surface area. Three different compositions have been studied (Al2O3-SiO2; Al2O3-SiO2+2%wt Ni; Al2O3-SiO2+10%wt Fe). The catalytic tests highlight the fact that the sample containing 2%Ni wt is the more appropriate in our conditions. [less ▲]

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