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See detailConvective drying : experimental campaign and numerical modelling
Hubert, Julien ULiege; Plougonven, Erwan ULiege; Léonard, Angélique ULiege et al

Conference (2017, June 19)

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See detailOptimiaztion of an electrophoretic approach for the screening and the development of new antithrombotic drugs
Farcas, Elena ULiege; Bouckaert, Charlotte; Servais, Anne-Catherine ULiege et al

Poster (2017, June 19)

The discovery of lead compounds that can modulate the activity of a biological target is essential to provide efficient pharmacological tools and to serve as starting points for new drug generations ... [more ▼]

The discovery of lead compounds that can modulate the activity of a biological target is essential to provide efficient pharmacological tools and to serve as starting points for new drug generations. Fragment-based drug discovery (FBDD) approach is an attractive tool for the identification of new selective inhibitors of a target of interest, but its success largely depends on the ability to develop screening bioassays capable to detect and gauge weak affinity binders. To achieve this goal, we investigated capillary electrophoresis (CE) for identifying and ranking fragments from an initial library. Indeed, due to its ability to evaluate weak interactions, CE seems to be promising for fragment-based screening. This technique is a powerful analytical tool with a unique separation mechanism, speed, efficiency and versatility. Its main advantages are low protein consumption, higher throughput compared to NMR and X-ray crystallography and the fact that screening can be carried out using native protein in physiological solution without the need of immobilization. We developed a proof of concept study on thrombin, a serine protease implicated in the coagulation cascade using affinity capillary electrophoresis (ACE) for ranking fragments from an initial library. For this study, we followed a probe ligand, benzamidine, and we investigated interactions with the target by monitoring the changes of its electrophoretic mobility upon binding. The first step of this study consisted in the optimization of the experimental conditions suitable for the CE method (target and probe ligand concentrations, separation buffer composition, voltage, separation effective length, target partial filling…). Then, numerous thrombin inhibitors with a wide range of inhibitory potency (i.e. Ki 200 µM – 5 nM) were tested to validate our system demonstrating the possibility to fish binders in the optimized conditions. We also checked the absence of non-specific binding with the target using the inactivated enzyme at the binding site. It is noteworthy that in this operating system (ACE assay), binding occurs in free solution using physiological buffers, thus preventing artifacts that may result from target immobilization, which is a requirement for some techniques such as SPR. [less ▲]

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See detailDesign and experimental validation of an adaptive control law to maximize power generation of a small-scale waste heat recovery system
Hernandez Naranjo, Jairo Andrés ULiege; Desideri, Adriano ULiege; Gusev, Sergei et al

in Applied Energy (2017), 203

Increasing the energy efficiency of industrial processes is a challenge that involves, not only improving the methodologies for design and manufacturing, but optimizing performance during part-load ... [more ▼]

Increasing the energy efficiency of industrial processes is a challenge that involves, not only improving the methodologies for design and manufacturing, but optimizing performance during part-load operation and transient conditions. A well-adopted solution consists of developing waste heat recovery (WHR) systems based on Organic Rankine Cycle (ORC) power units. The highest efficiency for such cycle is obtained at low superheating values, corresponding to the situation where the system exhibits time-varying nonlinear dynamics, triggered by the fluctuating nature of the waste heat source. In this paper, an adaptive control law using the Model Predictive Control (MPC) framework is proposed. This work goes a step beyond most of the existing scientific works in the field of ORC power systems, since the MPC controller is implemented in a lab-scale prototype, and its performance compared against a gain-scheduled PID strategy. The experimental results show that the adaptive MPC outperforms the gain-scheduled PID based strategy, as it allows to accurately regulate the evaporating temperature, while keeping vapor condition at the inlet of the expander i.e., the superheating, in a safe operating range, thus increasing the net power generation. [less ▲]

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See detailDEVELOPMENT AND VALIDATION OF A FAST SFC METHOD FOR THE ANALYSIS OF FLAVONOIDS IN PLANT EXTRACTS
Huang, Yang ULiege; Jiang, Zhengjin; Fillet, Marianne ULiege et al

Poster (2017, June 18)

Flavonoids from plants always show a wide range of biological activities [1-2]. In the present study, a rapid and highly efficient supercritical fluid chromatography (SFC) method was developed for the ... [more ▼]

Flavonoids from plants always show a wide range of biological activities [1-2]. In the present study, a rapid and highly efficient supercritical fluid chromatography (SFC) method was developed for the separation of 12 flavonoids. After careful optimization, the 12 flavonoids were baseline separated on a ZORBAX RX-SIL column using gradient elution. A 0.1% phosphoric acid solution in methanol was found to be the most suitable polar mobile phase component for the separation of flavonoids. From the viewpoint of retention and resolution, a backpressure of 200 bar and a temperature of 40 °C were shown to give the best results. Compared with a previously developed reverse phase liquid chromatography method, the SFC method could provide flavonoid separations that were about three times faster, while maintaining good peak shape and comparable peak efficiency. This SFC method was validated and applied to the analysis of five flavonoids (kaempferol, luteolin, quercetin, luteoloside, buddleoside) present in Chrysanthemum morifolium Ramat. from different cultivars (Chuju, Gongju, Hangju, Boju). The results indicated a good repeatability and sensitivity for the quantification of the five analytes with RSDs for overall precision lower than 3%. The limits of detection ranged from 0.73 to 2.34 μg/mL, while the limits of quantification were between 2.19 and 5.86 μg/mL. The method showed that SFC could be employed as a useful tool for the quality assessment of Traditional Chinese medicines (TCMs) containing flavonoids as active components. [less ▲]

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See detailStudy of the outer membrane permeability of Pseudomonas aeruginosa to ß-lactam antibiotics
Amisano, Francesco ULiege; Silvestri, Mauro ULiege; Mercuri, Paola ULiege et al

Poster (2017, June 17)

Background The resistance of Gram negative bacteria toward β-lactam antibiotics is caused by the interplay between four independent factors: i) the alteration of the sensitivity of the target enzymes, the ... [more ▼]

Background The resistance of Gram negative bacteria toward β-lactam antibiotics is caused by the interplay between four independent factors: i) the alteration of the sensitivity of the target enzymes, the penicillin-binding proteins, ii) the properties and concentration of the periplasmic β-lactamases, iii) the permeability of the outer membrane, iv) the efficiency of the active efflux system. On this basis, Zimmermann and Rosselet [1] proposed a model yelding a quantitative prediction of the MICs for gram-negative bacteria which was successfully applied to Escherichia coli and Enterobacter cloacae. This model seems to be less suitable in Pseudomonas aeruginosa due to its low outer membrane permeability which is mostly influenced by both a remarkable reduction of functional porins expression and an over-expression of efflux systems [2]. This decreased permeability causes difficulties in obtaining permeability coefficient direct measures. Moreover, the few published coefficients for P. aeruginosa are highly variable. For this purpose, BlaR-CTD, the C-terminal domain of a highly sensitive penicillin binding protein from Bacillus licheniformis, expressed in the periplasmic space, has been used in order to directly determinate of the concentrations of different β-lactams in this cell compartment and, consequently to obtain reliable measures of the permeability coefficient [3]. Methods P. aeruginosa PAO1 cells were incubated with different β-lactams, whose penetration into the periplasm is rapidly followed by the formation of a stable complex with BlaR-CTD. This latter was quantified in cells lysate by densitometric analysis, countermarking the free BlaR-CTD with a fluorescent β-lactam. The excess of the antibiotics will be hydrolysed by the addition of a class B β-lactamase. We used the same protocol for P. aeruginosa TNP004 [4], a PAO1 strain with a selective deletion of OprD porin, in order to study the influence of this single mutation for the antibiotic permeability. Results By the approach described above we determined the permeability coefficients of the external membrane of P. aeruginosa for different antibiotics belonging to the penicillin, cephalosporin and carbapenem sub-families. The comparison with the porin mutant strain showed similar coefficients for all the antibiotic tested except, as expected, for Imipenem Conclusion This work allowed a preliminary characterization of antibiotic permeability in P. aeruginosa which was poorly studied until now. Furthermore, we could apply this method to correlate the permeability with the role of porin deletions and/or efflux pumps overexpression in antibiotic resistant strains of clinical relevance. References 1 Zimmermann, W. and A. Rosselet. 1977. Function of the outer membrane of Escherichia coli as a permeability barrier to beta-lactam antibiotics. Antimicrob. Agents Chemother. 12:368–372. 2 Livermore D. M., and K. W. M. Davy. 1991. Invalidity for Pseudomonas aeruginosa of an accepted model of bacterial permeability to β-lactam antibiotics. Antimicrob. Agents Chemother. 35:916-921. 3 Lakaye B., Dubus A., Joris B., and J.M. Frère. 2002. Method for estimation of low outer membrane permeability to β-lactam antibiotics. Antimicrob. Agents Chemother. 46:2901-2907. 4 Yoneyama H., Yamano Y and T. Nakae. 1995 Role of porins in the antibiotic susceptibility of Pseudomonas aeruginosa: construction of mutants with deletions in the multiple porin genes. Biochem Biophys Res Commun. 213:88-95. [less ▲]

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See detailPanel moderator: enforcement and remedies
Van Cleynenbreugel, Pieter ULiege

Scientific conference (2017, June 17)

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See detailENMG du pied (atelier)
WANG, François-Charles ULiege

Conference (2017, June 17)

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See detailLe cours de philosophie et terminale, un lieu intermédiaire entre le domaine privé et le domaine public ? Une interprétation arentienne d'une expérience du savoir
Glorie, Caroline ULiege

in Implications Philosophiques (2017)

Partant du constat que la classe est traversée par une dimension politique (le programme de cours est fixé par le Ministère de l’Éducation nationale et vise à préparer les élèves à adopter les valeurs du ... [more ▼]

Partant du constat que la classe est traversée par une dimension politique (le programme de cours est fixé par le Ministère de l’Éducation nationale et vise à préparer les élèves à adopter les valeurs du citoyen), cet article cherche, dans un premier temps, à en tirer les conséquences concrètes. À l’aide d’une description critique de ce qui se joue en classe, ce premier moment vise à montrer que l’idéal politique qui sous-tend l’enseignement de la philosophie en Terminale a pour conséquence d’imposer une vision du monde « du dehors », ce monde des adultes auquel l’école doit préparer, comme un monde unifié. La manière dont le cours de philosophie doit se donner rejoue sans cesse le présupposé d’un monde non conflictuel. Ensuite, dans un second temps, cet article vise à interroger la nécessité de faire de la classe un lieu séparé du monde des adultes à l’aide des réflexions d’Hannah Arendt sur la dimension privée et sociale de l’école. Comment la classe peut-elle être un espace traversé par la pluralité au sens où l’entend Arendt alors même qu’il s’agit d’un espace privé ? [less ▲]

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See detailGeneralized Pascal triangles for binomial coefficients of finite words
Stipulanti, Manon ULiege

Conference (2017, June 16)

We introduce a generalization of Pascal triangle based on binomial coefficients of finite words. These coefficients count the number of times a finite word appears as a subsequence of another finite word ... [more ▼]

We introduce a generalization of Pascal triangle based on binomial coefficients of finite words. These coefficients count the number of times a finite word appears as a subsequence of another finite word. Similarly to the Sierpiński gasket that can be built as the limit set, for the Hausdorff distance, of a convergent sequence of normalized compact blocks extracted from Pascal triangle modulo 2, we describe and study the first properties of the subset of [0, 1] × [0, 1] associated with this extended Pascal triangle modulo a prime p. Then we create a new sequence from this extended Pascal triangle that counts, on each row of this triangle, the number of positive binomial coefficients. We show that this sequence is 2-regular. To extend our work, we construct a Pascal triangle using the Fibonacci representations of all the nonnegative integers and we define the corresponding sequence of which we study the regularity. This regularity is an extension of the classical k-regularity of sequences. [less ▲]

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See detailFirst Characterization of the Volatile Organic Compounds Emitted by Banana Plants (Musa sp.)
Berhal, Chadi ULiege; De Clerck, Caroline ULiege; LEVICEK, Carolina et al

Conference (2017, June 16)

Banana fruit (Musa sp.) ranks fourth in developing world's production, and has economical and nutritional key values. The popular and most dominant variety of the dessert banana group is the Cavendish ... [more ▼]

Banana fruit (Musa sp.) ranks fourth in developing world's production, and has economical and nutritional key values. The popular and most dominant variety of the dessert banana group is the Cavendish variety, and Plantain represents that status for the cooking banana group. Despite the importance of the Volatile Organic Compounds (VOCs), which are secondary metabolites with a high vapour pressure, in their utility in the plant protection and communication processes, they were never documented for the plant itself. Thus, the aim of this PHD thesis is to study the VOCs emitted by the plant, rather than their fruits or flowers. A protocol was optimized for the extraction of the banana plant's VOCs. The results of the first analysis showed 11 VOCs for the Cavendish, mainly (E,E)-α-farnesene (87.90 ± 11.28 ng/µl), methyl salicylate (33.82 ± 14.29) and 6-methyl-5-hepten-2-one (29.60 ± 11.66), and 14 VOCs for the Pacific Plantain cultivars, mainly (Z,E)-α-farnesene (799.64 ± 503.15),(E,E)-α-farnesene (571.24 ± 381.70) and (E) β ocimene (241.76 ± 158.49). Most of these compounds belong to the terpenes group (8 for Cavendish, 10 for Pacific Plantain). The other compounds detected were ketones, esters and aldehydes. Eight compounds were common between the two varieties (myrcene, Z and E β-ocimene, 6-methyl-5-hepten-2 one, 6-methyl-3,5-hepadien-2-one, a-farnesene, methyl salicylate and β-ionone). This exploratory study paves the way for an in-depth characterisation of VOCs emitted by Musa plants. [less ▲]

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See detailRelevance of early stretching in overhead athletes
Schwartz, Cédric ULiege; Tubez, François ULiege; Croisier, Jean-Louis ULiege et al

Conference (2017, June 16)

Overhead athletes often develop, over time, a tightness of the posterior structures of the shoulder, which may be associated with injuries. Ten symptomatic (with pain) and ten asymptomatic players with a ... [more ▼]

Overhead athletes often develop, over time, a tightness of the posterior structures of the shoulder, which may be associated with injuries. Ten symptomatic (with pain) and ten asymptomatic players with a tight shoulder were compared and the effect of a self-applied stretching program was evaluated. Before and after the stretching program, pain and stiffness of the shoulder were evaluated. Our results demonstrate that risk factors for shoulder pain such as glenohumeral internal rotation deficit and total range of motion deficit may only be limited in symptomatic athletes. The mobility of the shoulder was significantly improved after the stretching program for both groups. Pain was reduced when present. Because of the limited differences between the symptomatic and asymptomatic athletes, clinicians may find it advantageous to initiate early prevention or rehabilitation programs. [less ▲]

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See detailFrammenti d’intonaci di I stile a Ostia Antica. Un lotto inedito proveniente dagli strati preparatori di un mosaico tardo-repubblicano (Domus dei Bucrani - Camera dei Nani)
Morard, Thomas ULiege; Motta, Lucie ULiege

Conference (2017, June 16)

Les fouilles entreprises durant les années 2002-2010 sur le site de la Schola del Traiano (IV, IV, 15) à Ostia Antica ont révélé l’existence d’une domus tardo-républicaine - la Domus aux Bucranes (60-20 ... [more ▼]

Les fouilles entreprises durant les années 2002-2010 sur le site de la Schola del Traiano (IV, IV, 15) à Ostia Antica ont révélé l’existence d’une domus tardo-républicaine - la Domus aux Bucranes (60-20 av. J.-C.) - dont le système décoratif de IIe style (pavements, enduits peints et reliefs de stuc, plafonds) est apparu exceptionnellement bien conservé dans les couches les plus profondes de la parcelle urbaine concernée. Ce système décoratif - actuellement en cours de publication - a déjà été présenté à la communauté scientifique lors de différents colloques et journées d’études internationales. Il n’est pas question d’y revenir dans le cadre de la prochaine rencontre de l’AIRPA. En revanche, nous souhaiterions y présenter un lot d’enduits peints de Ier style jetés pêle-mêle dans les couches de préparation du tapis de mosaïque de la Chambre des Nains - un oecus aménagé durant les années 40-30 au sein de cette même domus tardo-républicaine. Restés inédits jusqu’à ce jour, ces fragments comptent parmi les plus anciens jamais découverts à Ostia Antica et leur position stratigraphique - scellée entre deux pavements bien datés - offre à n’en pas douter matière à réflexion. L’ensemble de ces fragments a fait l’objet d’une documentation systématique et des analyses archéométriques ont été portées sur les mortiers et les pigments des éléments les plus significatifs. Ce sont les résultats de cette entreprise scientifique que nous souhaiterions présenter lors du colloque de l'Aquileia afin de pouvoir intégrer cet ensemble décoratif de Ier style dans un corpus plus large - une mise en relation étroite avec le matériel contemporain découvert dans le Latium. [less ▲]

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See detailElaboration of an aqueous sol-gel method for the synthesis of g-Al2O3 supports
Lambert, Stéphanie ULiege

Conference (2017, June 16)

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See detailLe cartoon. Réflexions sur la culture populaire aux États-Unis
Moreau, Timothée ULiege

Conference (2017, June 16)

The aim of this paper is to propose an analysis of the cartoon and its place in popular culture from two different yet connected angles: the idea of "pop culture", linked to mass culture and its critique ... [more ▼]

The aim of this paper is to propose an analysis of the cartoon and its place in popular culture from two different yet connected angles: the idea of "pop culture", linked to mass culture and its critique/analysis by Adorno & Horkheimer and Benjamin ; and the idea of "folk culture", linked to the notion of grotesque as it is developped by Bakhtin. The main idea is that those two paths of analysis are connected through the notion of ambivalence and their link to political conceptions of a particular society and the culture that emerges from it. [less ▲]

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See detailLe point de vue onomasiologique – Réseaux de sens et cartes sémantiques
Winand, Jean ULiege

Scientific conference (2017, June 16)

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See detailNCA independence in the context of EU Regulation 1/2003: time to take incongruent accountability realities (more) seriously?
Van Cleynenbreugel, Pieter ULiege

Conference (2017, June 16)

This paper argues that the Commission’s reform suggestions aimed at streamlining NCAs into independent administrative agencies appear to neglect this variety of accountability mechanisms underlying ... [more ▼]

This paper argues that the Commission’s reform suggestions aimed at streamlining NCAs into independent administrative agencies appear to neglect this variety of accountability mechanisms underlying current NCA institutional organisation and functioning. Given that those mechanisms each harbour incongruent expectations regarding the organisation and functioning of independent NCAs, failure to acknowledge such incongruence may in practice lead to less effective competition law enforcement. The purpose of this paper is therefore to uncover the different NCA independence perspectives underlying those accountability mechanisms and to look for legally sound ways to make them converge when designing or upgrading NCA independence in the context of the Regulation 1/2003 reform. [less ▲]

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See detailMechanochemical Unfolding of Artificial Helical Foldamers by Single-Molecule Force Spectroscopy
Devaux, Floriane ULiege; Li, Xuesong; Huc, Ivan et al

Poster (2017, June 15)

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See detailDevelopment of an open-source algorithm based on inertial measurement units (IMU) of a smartphone to detect cattle grass intake and ruminating behaviors
Andriamandroso, Andriamasinoro ULiege; Lebeau, Frédéric ULiege; Beckers, Yves ULiege et al

in Computers & Electronics in Agriculture (2017), 139

In this paper, an open algorithm was developed for the detection of cattle’s grass intake and rumination activities. This was done using the widely available inertial measurement unit (IMU) from a ... [more ▼]

In this paper, an open algorithm was developed for the detection of cattle’s grass intake and rumination activities. This was done using the widely available inertial measurement unit (IMU) from a smartphone, which contains an accelerometer, a gyroscope, a magnetometer and location sensors signals sampled at 100 Hz. This equipment was mounted on 19 grazing cows of different breeds and daily video sequences were recorded on pasture of different forage allowances. After visually analyzing the cows’ movements on a calibration database, signal combinations were selected and thresholds were determined based on 1-s time windows, since increasing the time window did not increase the accuracy of detection. The final algorithm uses the average value and standard deviation of two signals in a two-step discrimination tree: the gravitational acceleration on x-axis (Gx) expressing the cows’ head movements and the rotation rate on the same x-axis (Rx) expressing jaw movements. Threshold values encompassing 95% of the normalized calibrated data gave the best results. Validation on an independent database resulted in an average detection accuracy of 92% with a better detection for rumination (95%) than for grass intake (91%). The detection algorithm also allows for characterization of the diurnal feeding activities of cattle at pasture. Any user can make further improvements, for data collected at the same way as the iPhone’s IMU has done, since the algorithm codes are open and provided as supplementary data. [less ▲]

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