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See detailEffect of plant defence elicitor on aphid and disease cross infestations
Bosquée, Emilie ULg; Oumarou, Saadatou; Qiu, Dewen et al

Poster (2014, June)

Various bio-aggressors can infest potato plants (Solanum tuberosum L.) throughout its life cycle. In addition to aphids, in particular Myzus persicae Sulzer which transmits Potato virus Y (PVY), plant ... [more ▼]

Various bio-aggressors can infest potato plants (Solanum tuberosum L.) throughout its life cycle. In addition to aphids, in particular Myzus persicae Sulzer which transmits Potato virus Y (PVY), plant pathogenic fungus such as Botrytis cinerea are able to cause damage. To determine the interactions between various bio-aggressors on potato plant defence mechanisms, (1) the effect of an attack by M. persicae followed by an attack by B. cinerea and vice versa, as well as (2) the effect of an elicitor on biological parameters of M. persicae and development of B. cinerea were assessed. On the other hand, (3) the effect of Botrytis cinerea and an elicitor on the efficiency of transmission of PVY by M. persicae was examined. The previous infection by B. cinerea resulted in a significant decrease in growth rate and a sharp reduction of M. persicae fertility, while the infection level of B. cinerea followed by M. persicae infestation was non-significant. Despite a reduction in growth and fertility of M. persicae during the first days of observation, the effect of elicitor on the biological parameters of M. persicae as well as on the development of B. cinerea was non-significant. Regarding the investigations on the PVY transmission by M. persicae, when the elicitor or Botrytis is previously applied on the plant, a significant reduction in the rate of transmission was observed. [less ▲]

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See detailReceptor expression in craniopharyngiomas causing tumor growth in pregnancy: case report and review of the literature
VROONEN, Laurent ULg; TOME, Monica; THIRY, Albert ULg et al

in Abstract book : 57èmes Journées Internationales d'Endocrinologie Clinique - Henri-Pierre Klotz (2014, June)

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See detailInvestigation of differential virus transmission efficiency in aphid strains: from biological to proteomic assays
Bosquée, Emilie ULg; Francis, Frédéric ULg

Poster (2014, June)

Aphids are well known for their variable efficiency in virus transmission to host plant. Not only aphid species but also aphid strain is an important factor to consider in the plant-aphid-virus ... [more ▼]

Aphids are well known for their variable efficiency in virus transmission to host plant. Not only aphid species but also aphid strain is an important factor to consider in the plant-aphid-virus interactions. In order to investigate these relations, different approaches should be developped from biological observations assessing the virus transmission efficiency to molecular tasks to better know the involved mechanisms in the aphid vector. After a period of virus acquisition on an artificial diet (depending on the kind of transmission, permanent or non permanent ways), the virus transmission rate were assayed and followed by the determination of the presence of virus in the aphid by PCR or immudetection. The aphids were then collected to investigate the variation of aphid proteome and potential involvement in virus interactions. Changes in protein expressions were investigated using a 2D-DIGE approach comparing most and least efficient aphid strains selecting different aphid – virus models (PVY and PLRV in potato, BYDV in wheat, CMV on tobacco) . The proteome changes were analysed using the samespot software. Protein spots with significant up- and down expressions were then mechanically picked, trypsin digested and analysed by Maldi-Tof-Tof. Significantly changed proteins were classify according to metablic pathways and biological functions. Interesting proteins found to probably interact with virus were not only detected from aphid but also from related bacterial symbionts. Theses results were discussed in order to better understand virus – vector relations and potentially promote new ways to control virus transmitted by hemipteran pest. [less ▲]

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See detailInhibitors of glycosylhydrolases as potential insecticides : focus on aphid model
Bosquée, Emilie ULg; Vandermoten, Sophie; Richel, Aurore ULg et al

Poster (2014, June)

Beside conventional neurotoxic compounds, new kinds of insecticides are investigated and new specific targets are in current research. According to the energy metabolic pathway, several enzymes are ... [more ▼]

Beside conventional neurotoxic compounds, new kinds of insecticides are investigated and new specific targets are in current research. According to the energy metabolic pathway, several enzymes are interesting to bring potential specific control of arthropods. Indeed, glycosylhydrolase group is very diversified from glucanases to trehalases, until chitinases. Different kinds of inhibitors were here tested to determine their potential role as new targetted aphicides. After different assays using the selected inhibitors in artificial diets, the most efficient molecules at 50-100 μg ml-1were kept for further proteomic tasks. The proteome patterns of aphids related to different inhibitor treatments were determined by two dimension electrophoresis, 2D-Differencial In Gel Expression (2D-Dige) coupled with mass spectrometry (ESI-MS-MS and Maldi-Tof-MS-MS) and data bank investigations. Particular proteins of interest were selected and accurately characterised with both fundamental but also applied views. Not only the carbohydrate metabolic pathway was disturbed with the use of glycosylhydolases inhibitors, other primary functions were also modified (amino acid synthesis, stress response, etc). This proteomic approach was discussed as an interesting and reliable tool to study the biologically involved proteins from aphids in response to specific tested enzymatic inhibitors with further ideas to be promoted as new insecticides to control insect pests. [less ▲]

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See detailEstudio ante y postmortem de las caracteristicas fisiopatologicas del tracto genital y sus factores de riesgo en vacas lecheras en el sur de Vietnam
Nguyen, Kien Cuong; Tomas Mulet, Cristina; Okouyi-Mfoumou, Marcel et al

Conference (2014, June)

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See detailColloque International "La Géographie Physique et les Risques Naturels" - Livre de résumés
Ozer, André ULg; Ozer, Pierre ULg

Book published by Université de Liège (2014)

Lors du Congrès de l’Association Internationale des Géomorphologues (AIG-IAG) qui s’est tenu à Paris en août 2013, plusieurs collègues ont demandé d’organiser à Liège le colloque inaugural de ... [more ▼]

Lors du Congrès de l’Association Internationale des Géomorphologues (AIG-IAG) qui s’est tenu à Paris en août 2013, plusieurs collègues ont demandé d’organiser à Liège le colloque inaugural de l’Association Francophone de Géographie Physique (AFGP). Profitant du ‘17th Joint Geomorphological Meeting’ déjà prévu du 30 juin au 3 juillet 2014 regroupant des géomorphologues de Belgique, France, Italie, Roumanie et Grèce, il a été proposé de nous réunir à Liège les 29 et 30 juin en prélude à cette réunion pour ‘lancer’ l’Association Francophone de Géographie Physique. Nous avons ainsi pu regrouper des amis francophones provenant de nombreux pays et réunis autour de la thématique du rôle de la géographie physique dans la gestion des risques naturels. Ce thème est cher à l’Université de Liège qui coordonne, depuis 2000, un Master complémentaire en Gestion des Risques Naturels ouvert aux pays francophones. Ce document présente les résumés des 27 communications scientifiques qui y seront présentées lors de ce Colloque intitulé "La Géographie Physique et les Risques Naturels". [less ▲]

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See detailBrussels IIbis Regulation - an appraisal of the application in Belgium
Wautelet, Patrick ULg

Report (2014)

This report, commissioned by the European Commission, undertakes to map out the practice of Belgian courts and authorities in relation to the Brussels IIbis Regulation (Regulation 2201/2003). It is based ... [more ▼]

This report, commissioned by the European Commission, undertakes to map out the practice of Belgian courts and authorities in relation to the Brussels IIbis Regulation (Regulation 2201/2003). It is based on a questionnaire submitted to experts in all Member States in the framework of a study on the assessment of the Regulation (EC) No 2201/2003 and the policy options for its amendment (call for tenders No JUST/2012/JCIV/FW/0195/A4). The purpose of this backward-looking evaluation is to assess the practical application and the effects of Regulation (EC) No 2201/2003 in terms of its relevance, coherence, effectiveness, efficiency, and EU added value and utility. [less ▲]

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See detailMembrane interactions of cyclic lipodepsipeptides from the viscosin group
Geudens, Niels; Feher, Krisztina; De Vleeschouwer et al

Poster (2014, June)

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See detailApplication of hyperspectral Raman imaging to the analysis of a self-emulsifying drug delivery system (SEDDS).
Sacre, Pierre-Yves ULg; De Bleye, Charlotte ULg; Netchacovitch, Lauranne ULg et al

Poster (2014, June)

Self-emulsifying drug delivery systems (SEDDS) are mixtures of drug and excipients that undergo emulsification when exposed to water. This pharmaceutical form is used to enhance the oral absorption of ... [more ▼]

Self-emulsifying drug delivery systems (SEDDS) are mixtures of drug and excipients that undergo emulsification when exposed to water. This pharmaceutical form is used to enhance the oral absorption of poorly water-soluble drugs. The API is finely dispersed in the excipients and forms a solid solution increasing its dissolution rate. Hyperspectral Raman imaging is a powerful tool that combines both spectral and spatial information. It returns qualitative and quantitative information useful during the development or the characterization of pharmaceutical preparations. The studied formulation consisted of a BCS 2 API (high permeability, low solubility) dispersed in excipients mainly composed of Lauroyl macrogol-32 glycerides (>50%). Two different preparations were analyzed: 100% of API dissolved and 70% of API dissolved with 30% of API powder added to the formulation. The two formulations have therefore exactly the same qualitative and quantitative composition but different spatial distribution and dispersion of the API mimicking a problem during the process. First a confocal Raman microscopic analysis was performed to evaluate the solid state of the API in the formulations. Then, an evaluation of the particle size was performed. These results are important since they can affect the bioavailability of the API and therefore its activity. Beside the microscopic scale analysis, a macroscopic imaging quantitative PLS model has been developed. The method has been validated within +/- 10% acceptance limits following the total error approach. This validated quantitative model enables reliable quantitative analysis at the pixel level of Raman images providing meaningful chemical images. [less ▲]

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See detailMulti-scale aquifer characterization and groundwater flow model parameterization using direct push technologies
Rogiers, Bart; Vienken, Thomas; Gedeon, Matej et al

in Environmental Earth Sciences (2014)

Direct push (DP) technologies are typically used for cost-effective geotechnical characterization of unconsolidated soils and sediments. In more recent developments, DP technologies have been used for ... [more ▼]

Direct push (DP) technologies are typically used for cost-effective geotechnical characterization of unconsolidated soils and sediments. In more recent developments, DP technologies have been used for efficient hydraulic conductivity (K) characterization along vertical profiles with sampling resolutions of up to a few centimetres. Until date, however, only a limited number of studies document high-resolution in situ DP data for three-dimensional conceptual hydrogeological model development and groundwater flow model parameterization. This study demonstrates how DP technologies improve building of a conceptual hydrogeological model. We further evaluate the degree to which the DP-derived hydrogeological parameter K, measured across different spatial scales, improves performance of a regional groundwater flow model. The study area covers an area of ~60 km² with two overlying, mainly unconsolidated sand, aquifers separated by a 5-7 m thick highly heterogeneous clay layer (in north-eastern Belgium). The hydrostratigraphy was obtained from an analysis of cored boreholes and about 265 cone penetration tests (CPTs). The hydrogeological parameter K was derived from a combined analysis of core and CPT data and also from hydraulic direct push tests. A total of 50 three-dimensional realizations of K were generated using a non-stationary multivariate geostatistical approach. To preserve the measured K values in the stochastic realizations, the groundwater model Krealizations were conditioned on the borehole and direct push data. Optimization was performed to select the best performing model parameterization out of the 50 realizations. This model outperformed a previously developed reference model with homogeneous K fields for all hydrogeological layers. Comparison of particle tracking simulations, based either on the optimal heterogeneous or reference homogeneous groundwater model flow fields, demonstrate the impact DP-derived subsurface heterogeneity in K can have on groundwater flow and solute transport. We demonstrated that DP technologies, especially when calibrated with site-specific data, provide high-resolution 3D subsurface data for building more reliable conceptual models and increasing groundwater flow model performance. [less ▲]

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See detailLe B.I.M et la maquette virtuelle comme moyen pédagogique permettant le rapprochement entre les cours d'informatique et l'enseignement du projet d'architecture
Boutemadja, Abdelkader ULg; Driesmans, Carine ULg; Jancart, Sylvie ULg

in Kubicki, Sylvain; Halin, Gilles; Bignon, Jean-Claude (Eds.) Scan 14 sémainaire de conception architecturale numérique : Interaction(s) des maquettes numériques (2014, June)

In the context of this paper, we pose the question of the conditions of possible link between computer courses and design projet. The integration of schools of architecture at universities is an ... [more ▼]

In the context of this paper, we pose the question of the conditions of possible link between computer courses and design projet. The integration of schools of architecture at universities is an opportunity to focus in the experiments made in this direction and to propose to implement the terms of this rapprochement. For us, it is important that this approach lies in the Bachelor years in a common core for all students. [less ▲]

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See detailDistributed Model-free Control of Photovoltaic Units for Mitigating Overvoltages in Low-Voltage Networks
Aristidou, Petros ULg; Olivier, Frédéric ULg; Hervas, Maria Emilia et al

in Proc. of CIRED 2014 workshop (2014, June)

In this paper, a distributed model-free control scheme to mitigate overvoltage problems caused by high photovoltaic generation in low-voltage feeders is proposed. The distributed controllers are ... [more ▼]

In this paper, a distributed model-free control scheme to mitigate overvoltage problems caused by high photovoltaic generation in low-voltage feeders is proposed. The distributed controllers are implemented on the photovoltaic inverters and modulate the active and reactive power injected into the network. In particular, they direct photovoltaic units first to consume reactive power and, if necessary, curtail active power generation to reduce high voltages in the feeder. [less ▲]

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See detailMODEL PREDICTIVE CONTROL OF CONGESTION AND VOLTAGE PROBLEMS IN ACTIVE DISTRIBUTION NETWORKS
Soleimani Bidgoli, Hamid ULg; Glavic, Mevludin ULg; Van Cutsem, Thierry ULg

in Proc. of CIRED Workshop 2014 (2014, June)

This paper presents a centralized control scheme, inspired of Model Predictive Control (MPC), to manage thermal overloads and correct abnormal voltages in real-time. The control scheme is able to smoothly ... [more ▼]

This paper presents a centralized control scheme, inspired of Model Predictive Control (MPC), to manage thermal overloads and correct abnormal voltages in real-time. The control scheme is able to smoothly bring the system within the desired limits, taking into account its near-future evolution. The control method effectiveness is illustrated on a 20-kV, 32-bus network hosting four distributed generation units. [less ▲]

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See detailThe two scenarios for quantum multifractality breakdown
Georgeot, Bertrand; Dubertrand, Rémy; Garcia-Mata, Ignacio et al

Scientific conference (2014, June)

Several types of physical systems are characterized by quantum wave func- tions with multifractal properties. In the quantum chaos field, they cor- respond to pseudointegrable systems, with properties ... [more ▼]

Several types of physical systems are characterized by quantum wave func- tions with multifractal properties. In the quantum chaos field, they cor- respond to pseudointegrable systems, with properties intermediate between integrability and chaos. In condensed matter, they include electrons in a disordered potential at the Anderson metal-insulator transition. This multi- fractality leads to particular transport properties and appears in conjunction with specific types of spectral statistics. In parallel, progress in experimental techniques allows to observe finer and finer properties of the wavefunctions of quantum or wave systems, as well as to perform experiments with un- precedented control on the dynamics of the systems studied. In this context, this talk will discuss the robustness of multifractality in presence of footnote- size perturbations. We expose two scenarios for the breakdown of quantum multifractality under the effect of such perturbations. In the first scenario, multifractality survives below a certain scale of the quantum fluctuations. In the other one, the fluctuations of the wave functions are changed at every scale and each multifractal dimension smoothly goes to the ergodic value. We use as generic examples a one-dimensional dynamical system and the three- dimensional Anderson model at the metal-insulator transition, and show that for different types of perturbation the destruction of multifractal properties always follows one of these two ways. Our results thus suggest that quantum multifractality breakdown is universal and obeys one of these two scenarios depending on the perturbation. We also discuss the experimental implica- tions. [less ▲]

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See detailEvaluation of troponin T on AQT90 Flex and COBAS 8000 as a rule in/out tool in an emergency ward
LE GOFF, Caroline ULg; EVRARD, Séverine ULg; BREVERS, Eric ULg et al

in Clinical Chemistry & Laboratory Medicine (2014, June), 52(Special Suppl), 510

BACKGROUND: Troponin measurement is the gold standard for diagnosis of Acute Myocardial Infarction (AMI). Troponin (highly sensitive (hs), T or I) is measured by immunochemistry instrument or by Point of ... [more ▼]

BACKGROUND: Troponin measurement is the gold standard for diagnosis of Acute Myocardial Infarction (AMI). Troponin (highly sensitive (hs), T or I) is measured by immunochemistry instrument or by Point of Care (POCT). POCT can be useful in emergency lab or ward for a faster diagnosis of patients with chest pain. Our study compared analytical performance of a POCT AQT90 Flex (Radiometer Medical) (AQT) and TnThs Cobas 8000 (Roche Diagnostics) (Cobas). We also compared the clinical performance of both methods at recommended cut-off (14 ng/L for Cobas and 30 ng/ L for AQT). METHODS: We selected 104 patients (296 samples) (range: 6-13822 ng/L) admitted in the Emergency ward for which at least 1 troponin determination (Cobas 8000) had been re-quested in the past 24 hours according to rule in/out procedure applied by this ward. Samples were then measured with the AQT. Inter-assay CV was maximum 8.6% and 9.6% for Cobas and AQT respectively. The cut-off defined as the 99th percentile for Roche was 14 ng/L and the recommended decision threshold value was 30 ng/L for Radiometer. Retrospective analysis of final diagnostic was obtained for all participants: we considered as “true positive” patients for whom a final diagnostic was ST segment-Elevation Myocardial Infarction (STEMI) or non STEMI (NSTEMI). RESULTS: On the whole range of measure, the 2 methods showed a good correlation (r2=0.98). Regression equation was Cobas = 0.98 AQT + 31 ng/L (95%CI of the intercept: (26.7;37.7) and 95% CI of the slope (0.96;1)). When we stratified, for the values <54 ng/L, the equation became Cobas = 0.52 AQT +1.1 ng/L (95%CI of the intercept: (-4.8;5.5) and 95% CI of the slope (0.39;0.69)). Bland and Altman plot did not show any bias. At admission [2-7 hours], 78 (81%) of admitted patients were finally considered as AMI, sensitivity was 92 % [96%] for Cobas and 78% [91%] for AQT. Specificity was 15% for Cobas (cut-off 14ng/L) or 73% (cut-off 54 ng/L) and 76% for AQT. CONCLUSIONS: Overall, there was a good correlation between the 2 methods. However, using a cut-off of 14 ng/L for Cobas is questionable for a rule in/out procedure in an emergency ward. Using 54 ng/L for Roche and 30 ng/L for AQT would have led to the best discrimination between patients presenting AMI or not. [less ▲]

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See detailURINARY AND SALIVARY CORTISOL IN LIQUID CHROMATOGRAPHY–TANDEM MASS SPECTROMETRY: METHOD VALIDATION AND EXPECTED VALUES DETERMINATION
LE GOFF, Caroline ULg; DELCOUR, Sandra ULg; PEETERS, Stéphanie ULg et al

in Clinical Chemistry & Laboratory Medicine (2014, June), 52(Special Suppl), 1241

BACKGROUND: Cortisol measurement is useful in evaluation of Cushing syndrome, adrenal insufficiency, mineralocorticoid excess and congenital adrenal hyperplasia. We developed a liquid ... [more ▼]

BACKGROUND: Cortisol measurement is useful in evaluation of Cushing syndrome, adrenal insufficiency, mineralocorticoid excess and congenital adrenal hyperplasia. We developed a liquid chromatography–tandem mass spectrometry (LCMS/MS) method for salivary and urinary cortisol and we determined the 95th percentile (p95) for the urinary and salivary cortisol. We compared them to the Mayo Clinic expected values. METHODS: Saliva at 8 am and 11 pm and 24h urine were obtained from 32 healthy (22 female, 34.3±9.3 yo) volunteers. We performed validation with the enoval software (Arlenda, Belgium). For the validation, we used water or urine with spiked known amounts of cortisol for the CORS and CTU respectively. For the CORS, samples were centrifuged, deuterium labelled cortisol was added as internal standard and the protein precipated by acetonitril. The supernatant was evaporated, dissolved in methanol acidified with acetic acid and analyzed by LCMS/MS. For CTU, samples were centrifuged, deuterium labelled cortisol was added as internal standard and diluted by the ammonium acetate and analyzed by LCMS/MS. At the Mayo Clinic, the expected values were 1-7.5 μg/L (7 a.m-9 a.m) and <1 μg/L (11-12 p.m) for CORS and 3.5-45 μg/24h (<18yo) for CTU. RESULTS: For the CTU, the with-in run did not exceed 3% (0.4-3%) and the between-run did not exceed 3.1% (0.4-3.1%) for 1.5-750 μg/L. The limit of quantification was 1.5 μg/L. The linearity was good between 1.5 and 750 μg/L. The recovery is 97.9±2.2% (95%CI for the mean: 92.4-101.1%). For the CORS, the with-in run and between run did not exceed 8% (1.9-8%) for 1.15-8.65 μg/L. The limit of quantification was 1.15 μg/L. The analyse presents a good linearity between 1.15 and 8.65 μg/L. The recovery is 99.9±2.9% (95%CI for the mean: 94.2-108.7%). The p95 for the CTU according to the CLSI C28-A3 was 33 μg/24h, and for the CORS was 5.42 μg/L at 8 am and 0.7 μg/L at 12 pm. CONCLUSIONS: Our developed method in liquid chromatography tandem mass spectrometry was validated for the measurement of urinary and salivary cortisol. Our findings indicate that the proposed analytical methods were suitable for routine purposes and useful in many pathological conditions.The expected values confirm these defined by the Mayo Clinic. [less ▲]

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