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See detailOptimization of a formic/acetic acid treatment of beech wood (Fagus sylvatica L.) for delignification
Simon, Mathilde ULg; Richel, Aurore ULg; Vanderghem, Caroline ULg et al

Poster (2011)

Lignin is a promising molecule constituting a renewable alternative to some petrochemical industry products. Lignin is an aromatic cross-linked heteropolymer composed of three phenylpropanoids (p ... [more ▼]

Lignin is a promising molecule constituting a renewable alternative to some petrochemical industry products. Lignin is an aromatic cross-linked heteropolymer composed of three phenylpropanoids (p-hydroxyphenyl, guaiacyl and syringyl units) linked together via radical coupling reactions by specific ether or carbon-carbon bonds. With this phenylpropanoid structure, lignin is a rich resource of biobased products that could find high-valued applications in a lot of different areas like petrochemical polymer reinforcement and replacement, antioxidants, stabilizers, resins and vanillin production... The first challenge of the valorization of lignins is their extraction from raw materials. Lignins can be found in different lignocellulosic substrates like grasses, softwood and hardwood. This extraction process needs the development of suitable biomass treatments, allowing efficient lignin recuperation without degradation. This one could lead to the loss of some interesting properties and so of some valorization possibilities. In this study, beech wood (Fagus sylvatica L.) was collected in the region of Gaume (Belgium). Beech wood particles were delignified at atmospheric pressure by a mixture of formic acid/acetic acid/water. A central composite design and response surface methodology were used for the optimization of treatment parameters for delignification. The optima of two independent variables, namely time (1h30, 3h, 4h30) and temperature (87°C, 97°C, 107°C), were determined on delignification yield, pulp yield, concentration of degradation products (furfural and hydroxymethylfurfural). Moreover, the impact of these two variables on the amount of residual linkages between phenylpropanoid units was evaluated by semi-quantitative bidimensional nuclear magnetic resonance spectroscopy (NMR-HSQC). Our results highlight that the delignification yields increase when cooking time and temperature are elevated. Nevertheless, under these conditions, pulp yield decreases as hydrolysis of hemicelluloses and cellulose occurs. The hydrolysates of carbohydrates (free sugars or oligosaccharides) are contained in the black liquor. At elevated temperature and time, the amount of degradation products in the black liquor is increased. [less ▲]

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See detailTransient reduction of placental angiogenesis in PAI-1 deficient mice
LABIED, Soraya ULg; BLACHER, Silvia ULg; Carmeliet, P et al

Poster (2011)

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See detailEndogenous zinc modulates di-synaptic GABAergic transmission in the dentate gyrus
Grauert, A; Engel, Dominique ULg; Ruiz, AJ

Poster (2011)

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See detailEffect of Chronic confinement stress on growth, survival, blood cortisol and glucose of perch (Perca fluviatilis)
Rougeot, Carole ULg; Tomson, Thomas; Vandecan, Michaël et al

Poster (2011)

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See detailEffect of prenatal undernutrition of the chicken embryo on growth and metabolism up to day 7
Willems, Els; Willemsen, Hilke; Li, Yue et al

Poster (2011)

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See detailExpansion of the Magdalenian in Northwest Europe
Miller, Rebecca ULg; Noiret, Pierre ULg

Poster (2011)

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See detailDistribution of Colonic Findings at Virtual Colonoscopy According to Gastrointestinal Symptoms in Almost 10,000 Patients
HOCK, D; OUHADI, R; MATERNE, R et al

Poster (2011)

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See detailDynamic Magnetic Resonance Perfusion: Influence of the Cardiac Cycle on Left Ventricle and Myocardial Signal Intensity Measurements
BROUSSAUD, T; AOUCHRIA, A; MANCINI, ISABELLE et al

Poster (2011)

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See detailDry Season Carbon Dynamics in Savannah Grassland and Rainforest Dominated River Basins of Madagascar
Marwick, T.; van Acker, K.; Darchambeau, François ULg et al

Poster (2011)

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See detailEffects of environmental factors on yield and milking number in dairy cows milked by an automatic system located in pasture
Dufrasne, Isabelle ULg; Robaye, Vincent ULg; Knapp, Emilie ULg et al

Poster (2011)

Nowadays, farmers have to manage larger herds but want, at the same time, benefit from a normal social life. The milking robot can bring solutions. Its use can reduce physical labour and allow flexibility ... [more ▼]

Nowadays, farmers have to manage larger herds but want, at the same time, benefit from a normal social life. The milking robot can bring solutions. Its use can reduce physical labour and allow flexibility. This technology results in a reduction in grazing even through grazing appears as a natural practice which is appreciated by the consumers. This project aims to develop strategies to use milking robots in pasture in order to benefit from advantages regarding feeding costs as well as animal welfare and health. It aims to study the effects of grass height, animal, days in milk, rotation cycle number and distance from grazed paddocks on daily milk yield and milking number of grazed cows. [less ▲]

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See detailIdentification and characterization of novel galectin-9 splice variants in endothelial cells
Heusschen, Roy ULg; De Bree, Martijn; Griffioen, Arjan et al

Poster (2011)

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See detailImpacts de nos actions d’accompagnement d’enseignants en développement professionnel au sein du Master Complémentaire Formasup
Delfosse, Catherine ULg; Dupont, Chantal ULg; Jérôme, Françoise ULg et al

Poster (2011)

Présentations des modalités d'analyse du master complémentaire en pédagogie de l'enseignement supérieur pour le réguler.

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See detailThick and crack-free nanocrystalline mesoporous TiO2 films obtained by capillary coating from aqueous solutions
Krins, Natacha ULg; Faustini, Marco; Louis, Benjamin et al

Poster (2011)

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See detailNovel HDAC/DNMT Twin Inhibitors Interfere with Angiogenesis
Shiva Shankar, Thammadihalli Veerasangaiah ULg; Sulka, Béatrice ULg; Blacher, Silvia ULg et al

Poster (2011)

DNA methylation and histone deacetylation are two key epigenetic modifications that play central role in regulation of gene expression. Several studies have shown that histone deacetylases (HDAC) and DNA ... [more ▼]

DNA methylation and histone deacetylation are two key epigenetic modifications that play central role in regulation of gene expression. Several studies have shown that histone deacetylases (HDAC) and DNA methyltransferases (DNMT) inhibitors are potent anti-angiogenic compounds. Though combination of HDAC and DNMT inhibitors are now being examined in clinical trials of hematological malignancies, little work has been done to understand the effect of this combination on physiological and tumoral angiogenesis. We have designed and tested a family of twin drugs with intrinsic HDAC and DNMT inhibitory activities in relevant models of angiogenesis in vitro (Human Umbilical Vein Endothelial Cells – HUVEC and aortic ring) and in vivo (chick chorioallantoic membrane and Zebrafish). We have identified a lead compound having quantifiable anti-angiogenic effect without cytotoxicity affecting global histone acetylation and DNA methylation levels. In order to elucidate its anti-angiogenic mechanism, we characterized gene expression pattern simultaneously with the methylation profile of HUVEC cells treated with the lead compound and reference epigenetic modulators. This approach based on parallel microarray analyses permitted us to underscore a list of genes exclusively affected by the lead compound but not by other HDAC or DNMT inhibitors. These genes were then analyzed using the Ingenuity Pathway software revealing potential involvement of a subset of genes in angiogenesis. Our present aim is to validate the expression levels of a series of genes with respect to epigenetic mechanisms (histone modifications and DNA methylation). Finally, the biological relevance of the target genes will be explored by RNA silencing. Hence, we are using these novel epigenetic modulators as a tool to understand the regulatory mechanism of angiogenesis and to develop effective approaches to treat cancer. [less ▲]

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See detailPilot Trials of STAR Target to Range Glycemic Control
Penning, Sophie ULg; Le Compte, Aaron; Massion, Paul et al

Poster (2011)

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See detailULTRASONOGRAPHIC APPEARANCE OF THE CISTERNA CHYLI IN THE DOG
Etienne, Anne-Laure ULg; Cavrenne, Romain ULg; Garcia et al

Poster (2011)

Introduction/Aims The cisterna chyli (CC) is a dilated and bipartite portion of the lymphatic channels coursing intimately along the abdominal aorta in the retroperitoneal space.1 The appearance of the CC ... [more ▼]

Introduction/Aims The cisterna chyli (CC) is a dilated and bipartite portion of the lymphatic channels coursing intimately along the abdominal aorta in the retroperitoneal space.1 The appearance of the CC of the dog has been described on magnetic resonance imaging.2 The aim of this poster is to describe the ultrasonographic appearance of the CC in 2 dogs with chylous ascitis and in 2 healthy dogs. Methods Abdominal ultrasonography was realised with a 7.5MHz microconvex transducer. A right or left lateral dorsal approach was used. The aorta (together with the cranial mesenteric artery in normal dogs) was used as the main landmark to localize the CC. The dogs with chylous ascites were a 4 year old female american cocker spaniel, with immune-mediated hemolytic anemia and thrombocytopenia and a 1 year old, spayed female whippet with recurrent pancreatitis. The 2 healthy dogs were a 7 year old Beagle and a 9 year old Jack Russell. The abdominal ultrasonography was realised within 2 hours after the meal in the healthy dogs. Results The CC was seen as a hypoechoic structure, without detectable flow, dorsal and to the right of the aorta. The CC was easily visible in the 2 dogs with chyloabdomen while it was more difficult to localize in the healthy dogs. The CC was tubular on the longitudinal images. On transverse images, the CC is elliptic or semilunar and may partially surround the aorta. The maximal width of the CC measured on transverse images varied from 2-3mm in the 2 healthy dogs to 4-8mm in the 2 dogs with chyloabdomen. In 3 patients some efferent/afferent lymphatic vessels were seen as thin hypoechoic tubes converging on the CC. Shape and size of the CC in the same animal were seen varying during the same ultrasonography or between different exams. Discussion/Conclusion The CC is visible by ultrasonography in dogs. Its visibility depends on different conditions like disease of the lymphatic system3, quality and distance of the meal. [less ▲]

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See detailSelf-DNA release mediates the adjuvant effects of aluminum salts
Marichal, Thomas ULg; Ohata, K; Bedoret, Denis et al

Poster (2011)

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See detailEvolutionary significance and trade-offs in life-history traits associated to ecological specialization and mating systems in the liverwort genus Radula Dumort.
Laenen, Benjamin ULg; Devos, Nicolas; Renner, Matt et al

Poster (2011)

Shifts in mating systems are amongst the most common and important transitions in plants and are correlated with a suite of life-history traits. The evolution of mating systems and their relationships to ... [more ▼]

Shifts in mating systems are amongst the most common and important transitions in plants and are correlated with a suite of life-history traits. The evolution of mating systems and their relationships to gametophyte size, sexual reproduction, formation of asexual diaspores, and ecological specialization, is examined here in the leafy liverwort genus Radula.More specifically, we attempt to answer the following questions:(1)What is the ancestral mating system in Radula? (2)Are shifts from one mating system to another directional or random? (3)How does the evolution of mating systems correlate with the evolution of other related life history traits and, in particular, the specialization to temporary habitats? (4)What are the contingence relationships and order of acquisitionof those traits? [less ▲]

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See detailRetrieving semantic information from persons’ names.
Barsics, Catherine ULg

Poster (2011)

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See detailLe Magdalénien dans le Nord-Ouest de l'Europe
Miller, Rebecca ULg; Noiret, Pierre ULg

Poster (2011)

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See detailReconstruction of satellite-derived sea surface temperature of the South China Sea in 2003-2009
Huynh, Thi Hong Ngu ULg; Alvera Azcarate, Aïda ULg; Beckers, Jean-Marie ULg

Poster (2011)

The South China Sea (SCS) is a large marginal sea in the tropical region where the percentage of missing data of the daily Advanced Very High Resolution Radiometer (AVHRR) sea surface temperature (SST) is ... [more ▼]

The South China Sea (SCS) is a large marginal sea in the tropical region where the percentage of missing data of the daily Advanced Very High Resolution Radiometer (AVHRR) sea surface temperature (SST) is very high. Here we use a relatively new technique, DINEOF (Data INterpolating Empirical Orthogonal Functions), to reconstruct the SST of the SCS in 2003-2009. Furthermore, a comparison between the reconstructed data and daily Tropical rainfall Measuring Mission Microwave Imager (TMI) SST is implemented. [less ▲]

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See detailOPTIMIZATION OF A NEW TWO-PLATE SCREENING METHOD FOR THE DETECTION OF ANTIBIOTIC RESIDUES IN MEAT.
Pham Kim, Dang; Degand, Guy ULg; Danyi, Sophie et al

Poster (2011)

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See detailRapid regulation by glutamate of aromatase activity
Charlier, Thierry ULg; Ball, Gregory; Balthazart, Jacques ULg

Poster (2011)

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See detailAqueous and non-aqueous sol-gel preparation of TiO2 films for the photocatalytic oxidation of ethanol in air
Cimieri, Iolanda; Poelman, Hilde; Lambert, Stéphanie ULg et al

Poster (2011)

One of the most versatile methods to prepare TiO2 fine powders and films is the sol-gel technique. It offers many advantages, among which the possibility to control the stoichiometry, work in mild and ... [more ▼]

One of the most versatile methods to prepare TiO2 fine powders and films is the sol-gel technique. It offers many advantages, among which the possibility to control the stoichiometry, work in mild and ambient atmospheric conditions and achieve high purity and homogeneity of the final product. Stable TiO2 sols were synthesized by an aqueous sol-gel process using titanium tetraisopropoxide (TTIP) as precursor and nitric acid in water as hydrolyzing agent. The aim of the present study was to investigate the influence of different solvents and different amounts of HNO3 on the photocatalytic activity of TiO2 in the breakdown of ethanol (EtOH) as VOC molecule under UV and visible light. In particular, ethanol, isopropanol and butanol were used as solvents and two different molar ratios of HNO3 with respect to TTIP (0.25 and 0.5 respectively) were used. Their effect was investigated with regard to the photocatalytic properties of the films obtained by spin coating on sodium free glass [1] and heat treated at 450°C in air. The microstructure, optical and morphological properties of the films were investigated using SEM, UV-Vis spectroscopy and ellipsometry. The nature of the crystalline phases was ascertained by X-ray diffraction and the surface area of the powders was measured by N2 adsorption. The porous TiO2 films obtained show quite good photocatalytic activity for the degradation of EtOH compared to titania films prepared using P25 Degussa as shown in Fig. 1. Further the photocatalytic properties of the thin films obtained by aqueous sol-gel method were compared with the activity of films prepared using the same titanium precursor by a non-aqueous sol-gel process, in which the hydrolysis is initialized by esterification reaction between acetic acid and alcohol. (Fig.1. EtOH degradation for P25 (green), non aqueous sol (purple) and aqueous sols prepared using ethanol as solvent and HNO3 in molar ratios 0.25(blue) and 0.50(red)) [1] H. Tomaszewski, K. Eufinger, H. Poelman, D. Poelman, R. De Gryse, P.F.Smet, G.B. Marin, Int. J. Photoenergy 8, 1 (2007) [less ▲]

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See detailIs the PASAT enough to detect working memory problems in MS patients? A comparison with another working memory test
DELRUE, Gaël ULg; MOYANO, Nicolas; JIMENEZ et al

Poster (2011)

We show that the PASAT is not the best test to evaluate working memory in mulitple sclerosis patients.

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See detailIs there really an Azores diversity enigma? Insights from the phylogeography of the heather Erica scoparia s.l.
Desamore, Aurélie ULg

Poster (2011)

The Azorean flora, in contrast to that of other archipelagos, is characterized by a paucity of evolutionary radiations and the widespread distribution of most endemics. Several hypotheses, including ... [more ▼]

The Azorean flora, in contrast to that of other archipelagos, is characterized by a paucity of evolutionary radiations and the widespread distribution of most endemics. Several hypotheses, including isolation from the continent, recent age, ecological homogeneity, and limited paleoclimatic variations, have been proposed to account for this pattern. These hypotheses are tested here within the context of the molecular phylogeography of the heather Erica scoparia s.l., a Mediterraneo-Atlantic species complex distributed across Macaronesia, North Africa and southwestern Europe. The marked molecular radiation of this species in the Azores, including an array of single-island endemics, suggests that the apparent homogeneity of the Azorean flora might, in fact, conceal undetected patterns of endemism that are similar to those observed in the Canarian flora for morphological data. Haplotype richness was higher in the Azores than in the Canaries and extensive dispersal mediated allopatry is apparent at the molecular level. The Azores were colonized at least twice independently by E. scoparia, whereas the Canarian haplotypes are monophyletic, suggesting that the greater distance between the Azores and the continent does not necessarily hamper the chances of successful colonization. [less ▲]

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See detailEarthworms smell microorganisms in soil
Zirbes, Lara ULg; Verheggen, François ULg; Mescher, Mark et al

Poster (2011)

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See detailUsing putative anti-auxins to improve somatic embryo maturation of Abies nordmanniana
Tahiri, Abdelghani ULg; Misson, Jean-Pierre; Kevers, Claire et al

Poster (2011)

In Belgium, the culture of Nordmann fir (Abies nordmanniana) is mainly located in Wallonia region. The planted area is estimated in average at 5000 ha  that annualy produce some 4 million Christmas trees ... [more ▼]

In Belgium, the culture of Nordmann fir (Abies nordmanniana) is mainly located in Wallonia region. The planted area is estimated in average at 5000 ha  that annualy produce some 4 million Christmas trees destined in priority to the export market. In vitro propagation by somatic embryogenesis is considered as an alternative method to seedlings for producing homogeneous and orthotropic trees on a large scale. Currently, the performances of the somatic embryo (SE) maturation is still insufficient to consider any commercial application of the technology. In this way , the effect of three substances  (2,3,5-triiodobenzoïque acid  as TIBA, 2 - (p-chlorophenoxy)-2-methylpropionic acids as PCIB, p-hydroxbenzoïque as PHBA)  reported as ''anti-auxins'' have been tested with three embryogenic lines on the formation and maturation of normal somatic embryos. [less ▲]

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See detailThe influence of aromatic solvents on CuPC blue pigments in oil paintings
Defeyt, Catherine ULg; Wijnberg, Louise; Verbeeck, Muriel ULg et al

Poster (2011)

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See detailRelease and innate immune detection of host cell DNA mediate the adjuvant activity of aluminum salts
Marichal, Thomas ULg; Ohata, K; Bedoret, D et al

Poster (2011)

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See detailThe promotive impact of high temperature on flowering in root chicory (Cichorium intybus L.)
Mathieu, Anne-Sophie; Vandoorne, Bertrand; Quinet, Muriel et al

Poster (2011)

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See detailBiophysical studies of trigger factors adapted to extreme biological temperatures
Struvay, Caroline; Piette, Florence; Feller, Georges ULg

Poster (2011)

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See detailPEB: thermal oriented architectural modeling for building energy efficiency regulations
Leclercq, Pierre ULg; Juchmes, Roland ULg; Delfosse, Vincent ULg et al

Poster (2011)

As part of the overhauling of the building energy efficiency regulations (following European directive 2002/91/CE), the Wallonia and Brussels-Capital Region commissioned the LUCID to develop an optional ... [more ▼]

As part of the overhauling of the building energy efficiency regulations (following European directive 2002/91/CE), the Wallonia and Brussels-Capital Region commissioned the LUCID to develop an optional 3D graphic encoding module to be integrated with the core energy efficiency computation engine developed by Altran Europe. Our contribution consisted mostly in analyzing the target users’ needs and representations (ergonomics, UI, interactions) and implementing a bespoke 3D CAD modeler dedicated to thermal models of buildings taking into account the various geometrical and relational constraints specific to thermal modeling. [less ▲]

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See detailVariability of insulin sensitivity for diabetics and non-diabetics during the first 3 days of ICU stay
Pretty, Christopher G.; Le Compte, Aaron; PREISER, Jean-Charles ULg et al

Poster (2011)

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See detailConstruction and validation of a new perceptual priming task: The contrasted word task
Geurten, Marie ULg; Meulemans, Thierry ULg

Poster (2011)

In clinical neuropsychology, different rehabilitation techniques – e.g., vanishing cues, spaced retrieval, errorless learning – developed for patients with memory impairments are considered to make use of ... [more ▼]

In clinical neuropsychology, different rehabilitation techniques – e.g., vanishing cues, spaced retrieval, errorless learning – developed for patients with memory impairments are considered to make use of the preserved implicit memory abilities shown by these patients, and notably the perceptual priming effects (Harrison et al., 2007). It might be therefore important for clinician neuropsychologists to determine whether these abilities are preserved or not in their patients. However, and quite surprisingly, assessment tools aimed at assessing implicit memory abilities in brain damaged patients are lacking. The aim of this study was to build and validate a new perceptual priming task – the contrasted word task – which could be used by neuropsychologists in their clinical practice. Seventy-two young healthy participants were included in this study, and were administered the contrasted word task in which 60 words counterbalanced in 2 orders and 3 types of priming (Visual; Auditory; New) emerged gradually from a white background on a computer screen. Subjects were asked to press the response key when they thought they had recognized the word. Results show a perceptual priming effect which is specific to the exposure modality (i.e., no inter-modality transfer), proving the efficacy of the contrasted word task to highlight a facilitated identification for words that were shown previously, and confirming the perceptual specificity of the priming effect (Schacter, 1992). [less ▲]

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See detailSedimentology and magnetic susceptibility on a continuous Lower Givetian to Lower Famennian fore-reef succession (Sauerland, Germany) : A new example which reinforce the use of MS for long-distance correlations (Germany, Belgium and Moravia).
Pas, Damien ULg; Da Silva, Anne-Christine ULg; Boulvain, Frédéric ULg et al

Poster (2011)

This study focuses on the continuous Givetian-Frasnian section of the abandoned Burgberg quarry (Messinghausen Anticline, northern margin of the Rhenish Mountains). The exposed section (102 m thick ... [more ▼]

This study focuses on the continuous Givetian-Frasnian section of the abandoned Burgberg quarry (Messinghausen Anticline, northern margin of the Rhenish Mountains). The exposed section (102 m thick) covers a well constraint stratigraphic interval starting at the base of the Givetian (Stritzke 1991;Aboussalam et al., 2003) and according to Stritzke (1991) and our new datations ending within the Lower Famennian. The Middle-Upper Devonian shelf-edge within the Rheinisches Schiefergebirge can be traced from the supposed position along the southern rim of the Dinant Syncline and the Eifel Synclines, northwards along a line connecting the southern margin of the Devonian reefal outcrops of Attendorn and Brilon (Krebs 1967, 1974). The depositional setting of the investigated section corresponds to complex slope and basinal environments where reworked material from the proximal Brilon platform (located to the north) and basin deposits coexist. Thus, this section allows to follow the evolution of the Givetian-Frasnian Brilon platform (e.g., Machel 1990; Stritze 1990, 1991) in a deeper setting. Petrographic analysis of more than 330 thin-sections leads to the identification of 7 microfacies which are integrated into a palaeoenvironmental model. Microfacies curve evolution shows two main trends. A shallowing upward trend ending within a typical proximal slope setting (dismantling of the platform) followed by a deepening upward trend which is characterized by several meter of pelagic mudstone within the upper part of the studied section. Magnetic susceptibility variations in sedimentary rocks, have commonly been interpreted as related to variations of detritic inputs through climatic or sea level changes (Crick et al., 1994). The magnetic susceptibility (MS) study of more than 330 samples from this long-time fore-reef carbonated succession is an opportunity to better constraint our sedimentological interpretations. To do so, we propose a comparison between general MS trends and some parameters such as microfacies and relative sea level fluctuations interpreted on the basis of the sedimentological study. The relatively long stratigraphic interval covered by the Burgberg section offers a good opportunity to compare our data with the time equivalent Devonian sections of the Ardennes (Belgium) and Moravian karst area (Czech Republic) (Boulvain et al., 2010). And thus to test the magnetic susceptibility tool for long-distance correlation between stratigraphically well constraint sections. [less ▲]

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See detailCT Peritoneography: Normal Anatomy of the Peritoneal Cavity and Implications for Diseases Assessment
OUHADI; MATERNE, R; GHEKIERE, O et al

Poster (2011)

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See detailMassive non-thermal radio emitters: new data and their modelling
Volpi, D.; Blomme, R.; De Becker, Michaël ULg et al

Poster (2011)

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See detailProduction subjective de rêve en milieu carcéral : une hypothèse adaptative
Englebert, Jérôme ULg; Gauthier, Jean-Marie ULg; Jacquemart, Catherine

Poster (2011)

Une étude sur le rêve n’est pas sans poser plusieurs questions épistémologiques et méthodologiques majeures. La première d’entre elles tient à l’essence même du rêve qui est un objet d’étude particulier ... [more ▼]

Une étude sur le rêve n’est pas sans poser plusieurs questions épistémologiques et méthodologiques majeures. La première d’entre elles tient à l’essence même du rêve qui est un objet d’étude particulier, étant strictement subjectif et difficilement objectivable. Le rêve n’existe dans la vie consciente qu’au passé ; il a une conscience uniquement rétrospective. Il existe donc un décalage temporel entre l’activité onirique et le discours sur le rêve. Ce hiatus temporel condamne donc le rêve à nous échapper dans sa finitude et pousse le chercheur à capituler face à la connaissance ultime et globale du monde imaginaire de l’individu. L’étude que nous avons réalisée se veut d’inspiration phénoménologique. Nous avons administré un questionnaire (questionnaire élaboré sous la supervision d’un collège d’experts travaillant en milieu carcéral) à une population de 48 détenus (43 hommes et 5 femmes) et à une population contrôle (appariée pour l’âge et le niveau d’étude). Le questionnaire était scindé en deux parties pour les détenus (rapport aux rêves avant l’enfermement [Gd.0] / rapport aux rêves maintenant [Gd.1]) et celui pour la population contrôle ne comprenait qu’une partie (rapport aux rêves maintenant [Gc]). Enfin, nous avons isolé trois groupes au sein de la population carcérale : Cp : Courte peine effectuée (maximum 90 jours), MP : Moyenne peine effectuée (plus de 90 jours et maximum 2 ans), LP : Longue peine effectuée (plus de 2 ans). Les résultats, qu’il conviendra de discuter dans le détail, mettent en évidence que l’activité onirique serait un mécanisme que le détenu utilise pour s’adapter à l’univers carcéral (la fréquence subjective de rêve et l’intérêt porté à ses rêves sont significativement plus importants pour le Gd.1 que le Gd.0 et le Gc). Mais ce constat tend à diminuer en fonction de la durée de la peine (au-delà de 2 ans d’enfermement [LP]). Nous pouvons expliquer cette diminution significative par un effet d’habituation (le rêve aurait permis un retour à une homéostasie psychique suffisante) ou par une abrasion du mécanisme. En effet, le rêve ne procurerait aucune modification dans le réel puisque le quotidien de l’enfermement reste le même. Privée de boucle de rétroaction, la fonction adaptative du rêve s’essoufflerait. [less ▲]

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See detailThick and crack-free nanocrystalline mesoporous TiO2 films obtained by capillary coating from aqueous solutions
Krins, Natacha ULg; Faustini, Marco; Louis, Benjamin et al

Poster (2011)

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See detailAn investigation of the relationships between foot conformation and distal interphalangeal joint effusion in young warmblood horses at the beginning of their training
Cubeddu, Francesca; Bastianacci, Valentina; Verwilghen, Denis et al

Poster (2011)

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See detailMyocardial Dynamic Contrast-enhanced MR: Artifacts and Physiopathological Pitfalls
NCHIMI LONGANG, Alain ULg; RASKINET, B; MORAR, A et al

Poster (2011)

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See detailThe effect of insulin injection on the glucose metabolism of the chicken embryo
Franssens, Lies; Willems, Els; Willemsen, Hilke et al

Poster (2011)

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See detailImpact of the treatment conditions of a formic/acetic acid delignification method on chemical structure and antioxidant activity of beech wood lignin
Simon, Mathilde ULg; Vanderghem, Caroline ULg; Richel, Aurore ULg et al

Poster (2011)

The interest in lignocellulosic substrates is increasing because they are clearly identified for their high potential of development in energy and value-added molecules production. Indeed lignocellulosic ... [more ▼]

The interest in lignocellulosic substrates is increasing because they are clearly identified for their high potential of development in energy and value-added molecules production. Indeed lignocellulosic biomass constitutes a promising resource for a sustainable production of organic compounds and biobased products that could progressively replace molecules from the petrochemical industry. Until now lignocellulosic substrates were mainly used for the valorization of cellulose. Hemicelluloses and lignins were less valorized and often degraded after the process. However, due to their phenolic structure, lignins can be valorized in a lot of high-valued applications like vanillin production, replacement of petrochemical polymers, antioxidants for cosmetics and food industry, resins… In this study, a representative sample of beech wood (Fagus sylvatica L.) was collected in the region of Gaume in Belgium. Beech wood was delignified at atmospheric pressure by an organosolv process using a mixture of formic acid/acetic acid/water. The effect of cooking time and temperature was evaluated on the structure, physico-chemical properties and antioxidant activity of the lignins obtained from the black liquor after treatments. The structural and physico-chemical characteristics of the lignins were investigated with different tools like infrared spectrometry, thermogravimetric analysis, gel permeation chromatography after acetylation of lignins, NMR 1H, 13C and HSQC. The antioxidant activity was assessed by a spectrophotometric method using the α,α-diphenyl-β-picrylhydrazyl radical (DPPH). [less ▲]

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See detailAnalyses biophysiques des interactions peptide-monocouches à l’interface air-eau
Nasir, Mehmet Nail ULg; Benichou, Emmanuel; Brevet, Pierre-François et al

Poster (2011)

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See detailSynthesis and hydrolytic stability of novel 3-[18F]fluoroethoxybis(1-methylethyl)silyl]propanaminebased prosthetic groups
collet, Charlotte; Lamandé-Langle, Sandrine; Balentova, Eva et al

Poster (2011)

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See detailUnpredictable photocatalytic ability of H2-reduced rutile-TiO2 xerogel in the degradation of dye-pollutants under UV and visible light irradiation
Páez Martínez, Carlos ULg; Lambert, Stéphanie ULg; Poelman, Dirk et al

Poster (2011)

Photocatalytic degradation of organic and inorganic pollutants on the TiO2 semiconductor has been extensively studied as a way to solve environmental problems relating to wastewater and polluted air ... [more ▼]

Photocatalytic degradation of organic and inorganic pollutants on the TiO2 semiconductor has been extensively studied as a way to solve environmental problems relating to wastewater and polluted air. Anatase and rutile are the most commonly used crystalline structures of TiO2, with anatase showing a higher photocatalytic activity attributed to its higher specific surface area and its favourable band gap energy (Eg). However, its high band gap (Eg = 3.2 eV) implies the use of UV light (lambda ≤ 380 nm) to inject electrons into the conduction band (TiO2(e-CB)) and to leave holes in the valence band (TiO2(h+VB)). Although the low band gap energy of rutile-TiO2 (Eg = 3.02 eV) allows rutile to potentially absorb more solar energy than anatase, the anatase-to-rutile phase transition leads to the collapse of the TiO2 specific surface area, which may result in a decrease in the photocatalytic activity of rutile. Low specific surface area and therefore poor absorption properties lead to strong limitations in exploring the photo-efficiency of rutile. Nevertheless, rutile has been proved to be comparable to anatase in its photoelectrochemical properties when used in dye-sensitized solar cells. In the present study, a new process for the reduction of rutile-TiO2 xerogel under hydrogen flow was developed to enhance the photocatalytic activity of TiO2 materials synthesized by the sol-gel process. So a series of H2-reduced TiO2 xerogels of low specific surface area was prepared by hydrolysis and condensation of tetraisopropoxy titanium(IV) in 2-methoxyethanol. The gels were dried under vacuum, calcined in air at different temperatures (400°C, 500°C and 700°C) and finally reduced in H2 at 400 °C. The materials were characterized by X-ray diffraction, transmission electron microscopy (TEM), FT-IR spectroscopy and UV/Visible diffuse reflectance spectroscopy. The texture was determined by nitrogen adsorption-desorption measurements. The effects of the calcination/reduction treatments on the adsorption of methylene blue (MB) in aqueous solution and on the photocatalytic degradation of MB and crystal violet (CV) under UV and visible light irradiation were also evaluated. Results showed predictable modifications in the physico-chemical properties caused by the annealing of TiO2 xerogel at high calcination temperature (700 °C), such as a total anatase-to-rutile phase transition and a considerable loss of specific surface area from 260 to 2 m2 g-1. However, the higher degree of reduction exhibited by the rutile-TiO2 lattice led to unpredictable photocatalytic activity for the dye conversion under UV and visible light irradiation: the loss of specific surface area of the rutile-TiO2 sample was compensated by the increase in the affinity of this sample for the dye. Under UV light irradiation, the rutile-TiO2 xerogel obtained after a calcination at 700 °C showed a similar level of photoactivity as the one obtained with anatase-TiO2 xerogels obtained by calcination at 400 °C and 500 °C. Under visible light, unlike anatase-TiO2 xerogels, the rutile-TiO2 xerogel showed a higher dye photoconversion rate per external surface area (40 times higher) than the commercial TiO2 Degussa P25. [less ▲]

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See detailFirst assessment of the biogeochemistry of the Congo River and tributaries
Darchambeau, François ULg; Bouillon, S.; Wabakanghanzi, J. N. et al

Poster (2011)

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See detailPreliminary results of financial analysis on poultry supply chains in Hanoi suburb, North-Vietnam
Phan Dang, Thang; Vu Dinh, Ton; Dogot, Thomas ULg et al

Poster (2011)

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See detailHuman brucellosis in North-East Ecuador: prevalence, typifying Brucella spp., and risk factors
Ron-Roman, J; Benitez-Ortiz, Washington; Ron-Garrido, L et al

Poster (2011)

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See detailSynthesis by sol-gel process of visible light sensitive-TiO2 for the degradation of pollutants and microorganisms
Tasseroul, Ludivine ULg; Lambert, Stéphanie ULg; Páez Martínez, Carlos ULg et al

Poster (2011)

Since the discovery of photocatalytic decomposition of water on TiO2 electrodes by Fujishima and Honda [1], heterogenous photocatalysis has been widely studied for environmental applications ... [more ▼]

Since the discovery of photocatalytic decomposition of water on TiO2 electrodes by Fujishima and Honda [1], heterogenous photocatalysis has been widely studied for environmental applications. Photocatalytic processes are new technologies for waste water treatment because new compounds (alkanes, pesticides, dyes, etc.) in effluents are not readily degraded by the conventional treatments [2]. Oxidative processes can completely destroy organic pollutants [3] or microorganisms (bacteria, viruses, fungi, etc.) [4,5]. At this moment, the commercial Degussa P25 is the mostly used photocatalyst. Nevertheless, it requires UV light to be activated, that is why scientists try to activate TiO2 under visible light. The aim of this study is to synthesize photocatalysts activated by visible light and to evaluate their activity for the degradation of pollutants and microorganisms. The sol-gel process allows the direct introduction of visible light sensitive species like porphyrins inside the TiO2 matrix during the synthesis [6]. Two tetracarboxyphenyl porphyrins are synthesized for the sensitization of TiO2 to visible light : the metal free tetracarboxyphenyl porphyrin and the nickel tetracarboxyphenyl porphyrin. These porphyrins are characterized by 1H NMR, FT-IR and UV/Vis spectroscopies. They are introduced during the sol-gel synthesis of TiO2 matrix. Diffuse reflectance and FT-IR spectroscopies are used to ensure that porphyrins are incorporated inside the matrix of TiO2. Indeed, characteristic porphyrins peaks appear on spectra. The cristallinity and specific surfaces of catalysts are also determined by XRD and nitrogen adsorption-desorption measurements respectively. The depolluting efficiency of photocatalysts is evaluated for the degradation in water of p-nitrophenol, which is listed as one of the 114 organic pollutants by the Environmental Protection Agency in the US. After 6 h under visible light, 40 % of p-nitrophenol are degraded with some catalysts. The activity is influenced by i) the presence of porphyrins : the photoactivity increases with the amount of porphyrins ; ii) the nature of porphyrins : nickel porphyrins are more active than free metal porphyrins ; and iii) the crystallinity of catalysts : amorphous catalysts are less active than crystallized samples. The photocatalysts with the highest degradation rating of dyes will be selected for the degradation in water of Escherichia coli and Lactobacillus acidophilus. [1] A. Fujishima, K. Honda, Nature 238, 37-38 (1972) [2] P. Gogate, A. Pandit, Advances in Environmental Research 8, 501-551 (2004). [3] D. Chen, A. Ray, Water Research 32, 3223-3234 (1998) [4] R. Watts, S. Kong, M. Orr, G. Miller, B. Henry, Water Research 29, 95-100 (1995). [5] J. Hong, M. Otaki, Journal of Bioscience and Bioengineering 101, 185-189 (2006). [6] C. Wang, J. Li, G. Mele, G.M. Yang, F.-X. Zhang, L. Palmisano, G. Vasapollo, Applied catalysis 78, 218-226 (2007). [less ▲]

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See detailThe glycine receptor is functionally expressed in migratory interneurons and influences early cortical development
Avila Macaya, Ariel Salvatore ULg; Nguyen, Laurent ULg

Poster (2011)

The strychnine-sensitive glycine receptor (GlyR) is a member of the ligand-gated ion channel superfamily. In the adult, the GlyR is known to mediate fast inhibitory neurotransmission in the spinal cord ... [more ▼]

The strychnine-sensitive glycine receptor (GlyR) is a member of the ligand-gated ion channel superfamily. In the adult, the GlyR is known to mediate fast inhibitory neurotransmission in the spinal cord and in the brainstem. The GlyR has also been described in the embryonic cortex after embryonic day 19 (E19) (Flint et al., 1998) where it could participate in developmental processes, but its presence at earlier stages has not been documented. Since other neurotransmitter systems, i.e. GABA and its receptors, are known to be potent signals that control corticogenesis (Nguyen et al., 2001; Ik-Tsen et al., 2007), we wondered if glycine and its GlyR could also fulfill such a function. In this study, we analyze GlyR expression and its physiological function in the early development of the cortex using in vitro cultures of embryonic day 13 slices, patch-clamp, two photon microscopy and immunocytochemistry. [less ▲]

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See detailDéontologie de l'information : journée d'étude
Vanesse, Marc ULg

Poster (2010, December 14)

Journée de réflexion sur la déontologie journalistique avec le bâtonnier de l'Ordre des avocats de Liège, le secrétaire général du Conseil de déontologie, un journaliste d'investigation et le secrétaire ... [more ▼]

Journée de réflexion sur la déontologie journalistique avec le bâtonnier de l'Ordre des avocats de Liège, le secrétaire général du Conseil de déontologie, un journaliste d'investigation et le secrétaire général adjoint de l'Association des journalistes. [less ▲]

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See detailChanges in functional interactions during anaesthesia-induced loss of consciousness
Schrouff, Jessica ULg; Perlbarg, Vincent; Boly, Mélanie ULg et al

Poster (2010, December 12)

Consciousness has been related to the amount of integrated information that the brain is able to generate. In this paper, we tested the hypothesis that the loss of consciousness caused by propofol ... [more ▼]

Consciousness has been related to the amount of integrated information that the brain is able to generate. In this paper, we tested the hypothesis that the loss of consciousness caused by propofol anesthesia is associated with a significant reduction in the capacity of the brain to integrate information. To assess the functional structure of the whole brain, functional integration and partial correlations were computed from fMRI data acquired from 18 healthy volunteers during resting wakefulness and propofol-induced deep sedation. Total integration was significantly reduced from wakefulness to deep sedation in the whole brain as well as within and between its constituent networks (or systems). Integration was systematically reduced within each system (i.e., brain or networks), as well as between networks. However, the ventral attentional network maintained interactions with most other networks during deep sedation. Partial correlations further suggested that functional connectivity was particularly affected between parietal areas and frontal or temporal regions during deep sedation. Our findings suggest that the breakdown in brain integration is the neural correlate of the loss of consciousness induced by propofol. They stress the important role played by parietal and frontal areas in the generation of consciousness. [less ▲]

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See detailA zealous parallel gradient descent algorithm
Louppe, Gilles ULg; Geurts, Pierre ULg

Poster (2010, December 11)

Parallel and distributed algorithms have become a necessity in modern machine learning tasks. In this work, we focus on parallel asynchronous gradient descent and propose a zealous variant that minimizes ... [more ▼]

Parallel and distributed algorithms have become a necessity in modern machine learning tasks. In this work, we focus on parallel asynchronous gradient descent and propose a zealous variant that minimizes the idle time of processors to achieve a substantial speedup. We then experimentally study this algorithm in the context of training a restricted Boltzmann machine on a large collaborative filtering task. [less ▲]

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See detailUse of pure ionic liquids as solvents for the lipase catalyzed synthesis of fatty acid sugar esters
Galonde, Nadine ULg

Poster (2010, December 10)

Sugar fatty acid esters are non-ionic surfactants commonly used in the pharmaceutical, cosmetic and food industries. Their enzymatic synthesis can be hindered by the low solubility of sugars in the ... [more ▼]

Sugar fatty acid esters are non-ionic surfactants commonly used in the pharmaceutical, cosmetic and food industries. Their enzymatic synthesis can be hindered by the low solubility of sugars in the organic solvents commonly used with lipases. Ionic liquids (ILs) have gained attention as particularly attractive “green” alternatives to organic solvents for carbohydrate biotransformation. Indeed, many ILs are good solvents for polar (e.g. carbohydrates) and less polar compounds. Furthermore, their use as reaction media can enhance the enzymatic reactivity, selectivity and stability. In this context, our study focused on the influence of using ILs as reaction medium for the lipase catalyzed synthesis of mannosyl myristate. The effect of the IL nature on the enzymatic reaction initial yield and rate was examined. [less ▲]

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See detailE.coli prpoS::gfp strain as biosensor of glucose heterogeneity inside industrial bioreactors
Brognaux, Alison ULg; Delvigne, Frank ULg; Thonart, Philippe ULg

Poster (2010, December 08)

• OBJECTIVE: Escherichia coli is a microorganism widely used in the industry for the production of recombinant proteins. The performances obtained at the laboratory level are not reproducible at a large ... [more ▼]

• OBJECTIVE: Escherichia coli is a microorganism widely used in the industry for the production of recombinant proteins. The performances obtained at the laboratory level are not reproducible at a large scale. Actually, the mixing operation is not efficient enough: gradients of glucose and oxygen appear when operating in fed-batch mode (addition of glucose during the culture). These gradients cause adverse impacts on the production of biomass and recombinant protein. The aim of this work is to use the microbial population as biocaptor of the encoutered stress inside heterogeneous industrial bioreactors to better scale-up and regulate these reactors. • MATERIALS AND METHODS: A plasmid carrying a stress promoter followed by the coding sequence of the Green Fluorescent Protein (GFP) is introduced in the bacterial host (in our case, the strain E. coli K12 will be considered as a model organism). When the cell is submitted to given stress condition, GFP synthesis is induced and accumulated into the cytoplasm, leading to the increase of the cell's fluorescence. Flow cytometry detection is used in order to quantify the fluorescence at the single cell level. Obtained results are frequency histograms of fluorescenceintensity in the microbial population • RESULTS: The rpoS gene is a gene of the general stress response, mainly induced at the entrance to stationary phase (during a lack of glucose). The tracking of the GFP fluorescence linked to the activation / repression of the rpoS promoter gives good results. Indeed, there is appearance of a segregation at the level of the GFP content among the microbial population. The intensity of the segregation, as well as its time of appearance during the culture can be related to the bioreactor mixing efficiency. • CONCLUSION: prpoS::gfp strains can be used as biosensors of the heterogeneity of glucose encountered inside industrial reactors. • POTENTIAL APPLICATIONS & KEY BENEFITS: These strains could be used to validate a fed-batch regulation (addition of glucose) at the industrial level. [less ▲]

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See detailAzoxystrobin and epoximazole sensitivity profiles of Mycosphaerella graminicola populations from the Grand-Duchy of Luxemburg in 2007 and 2008
Vrancken, Carine; Dubos, Tiphaine; El Jarroudi, Moussa ULg et al

Poster (2010, December 07)

Mycosphaerella graminicola strains were isolated from symptomatic winter wheat (Triticum aestivum) and spelt (Triticum spelta) leaves sampled across the Grand-Duchy of Luxembourg. In total, 484 strains ... [more ▼]

Mycosphaerella graminicola strains were isolated from symptomatic winter wheat (Triticum aestivum) and spelt (Triticum spelta) leaves sampled across the Grand-Duchy of Luxembourg. In total, 484 strains were isolated from winter wheat, and 31 from spelt leaves. The sensitivity profiles of these strains towards azoxystrobin (Amistar®, Syngenta Agro GmbH, Germany) and against epoxiconazole (Opus®, BASF Belgium NV/S A, Brussels, Belgium) were assessed in microplates, allowing to test 10 different concentrations for each active substance (0, 0.00316, 0.01, 0.0316, 0.1, 0.316, 1, 3.16, 10 and 31.6μg/mL). 100μ g/mL of salicylhydroxamic acid (SHAM) was also added to the medium, in order to prevent the strains from using alternative respiration. Results of the sensitivity tests for azoxystrobin showed a dose-dependent decrease of in vitro growth for all the strains. During both years, strains could be divided into two distinct sub-populations in relation to their azoxystrobin sensitivity, thus forming a bimodal distribution commonly reported to be associated with a single gene-mediated resistance. For wheat, the dominant sub-population was the one showing full resistance to azoxystrobin. The results of the sensitivity tests to epoxiconazole in liquid media showed a dose-dependent decrease of fungal growth for all the strains tested. The EC50 values followed an unimodal distribution. When the sensitivity distribution of the strains collected in 2008 (n=379) was compared to that observed in 2007, although the populations have remained unimodal, a minor shift towards less sensitive populations was observed. Compared to strains originating from wheat, the spelt strains were more sensitive towards both fungicides (p ≤ 0.001). [less ▲]

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See detailEvaluating analytical results reliability using a Bayesian probability criterion
Rozet, Eric ULg; Lebrun, Pierre ULg; Boulanger, Bruno ULg et al

Poster (2010, December 02)

In pharmaceutical industries, quantitative analytical methods such as HPLC play a key role. Indeed, the analytical results obtained from them are used to make crucial decisions such as the release of ... [more ▼]

In pharmaceutical industries, quantitative analytical methods such as HPLC play a key role. Indeed, the analytical results obtained from them are used to make crucial decisions such as the release of batches of drugs, the evaluation of safety and efficacy of new drug candidates or the monitoring of patients health. Prior to their routine use, analytical methods are submitted to a stringent validation study where they have to demonstrate that they are fit for their final purpose, i.e. providing accurate result . Typically this demonstration is made by either providing point estimates of systematic error (bias) and random error (variance) or sometimes by providing interval estimates of these statistical parameters at several well defined concentration levels of the target analyte. They are then compared to maximum acceptable levels. More recently, tolerance intervals approaches have been proposed that are evaluated in a similar way at these key concentration levels. However none of these decision approaches allow knowing the probability to obtain accurate results over the whole concentration range of interest. Frequentist approximations have been proposed to estimate this probability but only at the concentration levels experimentally tested and not for the whole range of interest. In this work, a linear hierarchical Bayesian approach is proposed. It takes into account the potential random characteristic of the slope and intercept observed from one analytical run to the other, and also integrates the possible covariance between the parameters. Additionally, heteroscedasticity of the residual variance over the concentration range investigated is taken into account. A situation regularly observed in practice. Finally a reliability profile for the whole concentration range studied is obtained using MCMC sampling. This profile provides the probability (Prel) to obtain accurate results over the full concentration range investigated. This profile is then compared to a minimum reliability probability (Pmin) that will define the valid concentration range of the analytical method. The usefulness of this approach is illustrated through the validation of a bioanalytical method and also compared with a one concentration level at a time frequentist approach derived from tolerance intervals. [less ▲]

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