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See detailFast and Reliable Method for the Preparation of Various [18F]Fluorobenzyl Halides
Lemaire, Christian ULg; Libert, Lionel ULg; Plenevaux, Alain ULg et al

in Journal of Labelled Compounds & Radiopharmaceuticals (2009, July), 52(S1), 178

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See detailBedload progression in gravel bed rivers using iron slag as a tracer
Houbrechts, Geoffrey ULg; Levecq, Yannick; Mols, Julien et al

Poster (2009, July)

In fluvial dynamics studies, different methods are used to evaluate bedload transport and particle travel lengths. However, results are mostly based on a few transported elements and on a relatively short ... [more ▼]

In fluvial dynamics studies, different methods are used to evaluate bedload transport and particle travel lengths. However, results are mostly based on a few transported elements and on a relatively short time scale. Consequently, it is difficult to extrapolate these results to whole bedload, because of the burying of particles into the subsurface layer or the trapping of elements in fluvial forms (point bars, riffles, …), which can immobilise elements during long periods. Bedload progression has been evaluated in Ardenne rivers using slag elements produced by the past factories established along rivers between the 14th and the 19th centuries. Important quantities of slag were dumped close to rivers or even directly into channels. For several centuries, slag elements were dispersed in the bedload and transported by floods of varying importance. Consequently, slag can be considered as a tracer to analyze bedload progression over several centuries. The size of slag elements has been studied in many Ardenne rivers. The longitudinal size trend of the largest slag particles allows us to determine the effective competence of rivers and to analyze the hydraulic sorting. Moreover, downstream of some metallurgic sites, we have constrained the presence of slag elements to the most downstream riffles. Because we know from historical studies the periods of activities of these sites, we may estimate the speed of bedload progression in several gravel bed rivers from the Ardenne Massif (2-3 km/century). [less ▲]

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See detailAnalysis of dynamic response of a very flexible Delta wing model in a wind tunnel
Barbason, Mathieu ULg; Andrianne, Thomas ULg; Hickey, Daryl ULg et al

in Proceedings of the 2009 International Forum on Aeroelasticity and Structural Dynamics (2009, July)

Limit cycle oscillations involving Delta wings are an important area of research in modern aeroelasticity. Such phenomena can be the result of geometric nonlin- earity, aerodynamic nonlinearity or under ... [more ▼]

Limit cycle oscillations involving Delta wings are an important area of research in modern aeroelasticity. Such phenomena can be the result of geometric nonlin- earity, aerodynamic nonlinearity or under-wing store nonlinearity. In this paper, a flexible half-Delta wing without stores is tested in a low speed wind tunnel in order to investigate its dynamic response. It is found that, at several combinations of airspeed and angle of attack, the wing undergoes high amplitude limit cycle oscillations. Three types of such oscillations are observed. Type 1 oscillations occur only at low angles of attack and are the result of a Hopf-type bifurcation. Type 2 limit cycle oscillations occur at intermedi- ate angles of attack and are the result of an atypical bifurcation. In other words, these oscillations appear as the airspeed is increased but disappear at even higher airspeeds. Type 3 oscillations occur at even higher angles of attack. A bispectrum analysis shows that type 3 limit cycle oscillations feature quadratic phase coupling. No such coupling was measured for type 2 oscillations, leading to the conclusion that the nonlinearity must be of higher order. [less ▲]

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See detailDevelopment and use of equation based simulation tools to support audit of commercial buildings
Bertagnolio, Stéphane ULg; Lebrun, Jean ULg; Andre, Philippe ULg

in Proceedings of the eleventh International IBPSA Conference, Glasgow, UK (2009, July)

A series of new simulation tools are being developed to help the building energy auditor in establishing his diagnosis (including benchmarking and detailed analysis of actual energy consumption) and in ... [more ▼]

A series of new simulation tools are being developed to help the building energy auditor in establishing his diagnosis (including benchmarking and detailed analysis of actual energy consumption) and in evaluating the selected Energy Conservation Opportunities (ECOs). The Building-HVAC System global models presented here include simplified models of building zones and of HVAC equipment. Only a limited number of easily identifiable parameters is required. The simplicity of the models and the use of an equation solver to run the simulation ensure good robustness and full transparency. The development, the implementation and the use of these models are discussed in the present paper. Focus is also given to the calibration of the tools to the monthly utility bills. [less ▲]

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See detailTIME-DEPENDENT PREFERENTIAL IN VIVO D2 OCCUPANCY BY AMISULPRIDE IN THE MEDIAL STRIATUM – CONTINUOUS MEASUREMENT USING A BETA MICROPROBE SYSTEM
Warnock, Geoffrey ULg; Goblet, David ULg; Lemaire, Christian ULg et al

in Journal of Labelled Compounds & Radiopharmaceuticals (2009, July), 52(S1), 105

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See detailAction-research in inter-organizational partnerships: can the institutional entrepreneur theorize his/her own institutionalization practices?
Xhauflair, Virginie ULg; Pichault, François ULg

Conference (2009, July)

In the current context of a crisis in social regulation, the issue of institutionalisation of new forms of compromise has gained central importance. The “local” level is increasingly more often presented ... [more ▼]

In the current context of a crisis in social regulation, the issue of institutionalisation of new forms of compromise has gained central importance. The “local” level is increasingly more often presented as one of the levers for recasting social regulation. This involves designing a new framework for interaction between the micro-economic stakeholders on the labour market. In this way, our research focused on the conditions for institutionalisation of compromises implemented at inter-company level conciliating the need for flexibility and security. We adopted a field approach, anchored in “flexicurity” practices implemented at local level. In order to do this, we set up a partnership made up of the various stakeholders on the labour market in our region, within the framework of a European action-research project. With these partners’ collaboration, we observed the existing practices and tested new practices as part of pilot projects, whose failure and/or success (qualified in terms of “desirability” of the compromises implemented) provided us with a wealth of longitudinal data. Having become veritable “institutional entrepreneurs” through spurring on and supporting these experiments, we have contributed to the development, alongside our “practitioner” partners, of a flexicurity practices analysis grid. It allows their desirability to be qualified and helps guide the implementation of such innovations. We then returned to our status of researchers, transforming this “local” knowledge into generic knowledge actionable through an abductive process that establishes links between our own theorisation and the existing knowledge in the scientific field. [less ▲]

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See detailGenetic variability of test-day stearoyl coenzyme-A desaturase 9 activity
Arnould, Valérie ULg; Gengler, Nicolas ULg; Soyeurt, Hélène ULg

Conference (2009, July)

Milk fatty acid (FA) profile is far from the optimal fat composition in regards to human health. Different natural sources of variation such as feeding or genetics could be used to modify the contents of ... [more ▼]

Milk fatty acid (FA) profile is far from the optimal fat composition in regards to human health. Different natural sources of variation such as feeding or genetics could be used to modify the contents of unsaturated fatty acids. The impact of feeding is well described; however, genetics effects on the milk FA composition are not well studied. Increasing the unsaturated fatty acids contents of bovine milk could have the potential to raise the nutritive and therapeutic values of dairy products. The stearoyl Coenzyme-A desaturase 9 (delta-9) gene was identified as a potential functional candidate gene affecting milk fat composition in dairy cattle. The objective of this research was to study the genetic variability on this enzyme activity across lactations. A total of 199,977 test-day records were obtained from 29,603 Holstein cows in first lactation, 154,267 records from 23,453 Holstein cows in second lactation, and 173,244 records from 75,887 Holstein cows in third and later lactations. The used model was a multiple-trait random regressions test-day model. Fixed effects were: herd × date of test, and class of age. Random effects were: herd × year of calving, permanent environmental, additive genetic, and residual effects. The studied traits were milk yield, protein content, percentage of fat, monounsaturated fatty acids estimated by mid-infrared spectrometry, and the ratios reflecting the delta-9 activity. Obtained heritability estimates of delta-9 as well as the genetic and phenotypic correlations varied across lactations. These results suggest potential improvements of milk fat composition based on delta-9 activity using animal selection and appropriate management practices. [less ▲]

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See detailUSE OF A BETA MICROPROBE SYSTEM AS AN AFFORDABLE TRANSLATIONAL TOOL COMPARED TO PET – EXAMPLES USING FDG AND 18F-FALLYPRIDE BINDING
Warnock, Geoffrey ULg; Goblet, David ULg; Lemaire, Christian ULg et al

in Journal of Labelled Compounds & Radiopharmaceuticals (2009, July), 52(S1), 55

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See detailProcedural Law in Tax Law – Belgian Report
Richelle, Isabelle ULg

Conference (2009, July)

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See detailA dissipative approach to the identification of biochemical reaction networks
Fey, Dirk ULg; Bullinger, Eric ULg

in 15th IFAC Symposium on System Identification, Saint Malo, France (2009, July)

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See detailTesting and validation of simulation tools of HVAC mechanical equipment including their control strategies. Part III: Validation of an air-cooled chiller model
Lemort, Vincent ULg; Lebrun, Jean ULg; Felsmann, Clemens

(2009, July)

This paper presents a semi-empirical steady-state model of an air-cooled water chiller. The first part of the paper shows how the model is built by associating a scroll compressor and two heat exchanger ... [more ▼]

This paper presents a semi-empirical steady-state model of an air-cooled water chiller. The first part of the paper shows how the model is built by associating a scroll compressor and two heat exchanger sub-models. The second part of the paper presents the parameters identification process based on published manufacturer data (for the compressor and the whole chiller models). The only encountered difficulty is the characterization of the fan control model, since information is lacking to identify its parameters. The third part of the paper presents results of an experimental investigation carried out on the same chiller integrated into an existing cooling plant. A detailed analysis of the experimental data allowed a better understanding of the chiller’s operation and a better identification of the model’s parameters (such as the models of the fan control and of the compressor staging control). Moreover, a simple but realistic model of the condenser hot gas by-pass was introduced. As a result, deviations between predictions by the model and the experimental data were considerably reduced. The model is finally found to predict the total cooling energy and the total electrical consumption over a long-term simulation period with a very good accuracy. [less ▲]

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See detailUnderstanding the controversies of inter-organizational ambidexterity with actor-network theory
Antoine, Mélanie ULg; Degré, Julie ULg

Conference (2009, July)

Generally considered at an intra-organisational level, ambidexterity can also be found at inter-organisational level where organisations decide to collaborate by sharing between them activities of ... [more ▼]

Generally considered at an intra-organisational level, ambidexterity can also be found at inter-organisational level where organisations decide to collaborate by sharing between them activities of exploration and exploitation, according to their core competence. In this paper, we examine these collaborations, which are often presented as win-win solutions. In two case studies of R&D partnerships receiving public financing, we show the tensions that run through these alliances and the controversies that set the partners against each other. Our analysis, based on the actor-network theory, indicates that the conditions for successful inter-organisational ambidexterity do not exist a priori. The success of a partnership rather relies on a continuous translation process creating the convergence between the parties involved. [less ▲]

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See detailTesting and validation of simulation tools of HVAC mechanical equipment including their control strategies. Part I: Description of the validation test cases
Felsmann, Clemens; Lebrun, Jean ULg; Lemort, Vincent ULg et al

(2009, July)

This paper presents the work carried out under Subtask D of the International Energy Agency SHC Task 34/ECBCS Annex 43 (Testing and Validation of Building Energy Simulation Tools). The goal of this ... [more ▼]

This paper presents the work carried out under Subtask D of the International Energy Agency SHC Task 34/ECBCS Annex 43 (Testing and Validation of Building Energy Simulation Tools). The goal of this Subtask (Mechanical Equipment and Control Strategies) was to develop methods to help evaluating, diagnosing and correcting HVAC mechanical equipment simulation software. [less ▲]

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See detailSimplified time-domain simulation of detailed long-term dynamic models
Fabozzi, Davide ULg; Van Cutsem, Thierry ULg

in Proceedings of the 2009 IEEE PES General Meeting (2009, July)

Time-domain simulation of power system long-term dynamics involves the solution of large sparse systems of nonlinear stiff differential-algebraic equations. Simulation tools have traditionally focused on ... [more ▼]

Time-domain simulation of power system long-term dynamics involves the solution of large sparse systems of nonlinear stiff differential-algebraic equations. Simulation tools have traditionally focused on the accuracy of the solution and, in spite of many algorithmic improvements, time simulations still require a significant computational effort. In some applications, however, it is sufficient to have an approximate system response of the detailed model. The paper revisits the merits of the Backward Euler method and proposes a strategy to control its step size, with the objective of filtering out fast stable oscillations and focusing on the aperiodic behaviour of the system. The proposed method is compared to detailed simulation as well as to the quasi-steadystate approximation. Illustrative examples are given on a small but representative system, subject to long-term voltage instability. [less ▲]

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See detailTHE USEFULNESS OF AN ARTERIOVENOUS SHUNT COMBINED WITH A BETA MICROPROBE FOR THE MEASUREMENT OF INPUT FUNCTION IN RATS
Warnock, Geoffrey ULg; Goblet, David ULg; Lemaire, Christian ULg et al

in Journal of Labelled Compounds & Radiopharmaceuticals (2009, July), 52(S1), 106

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See detailA Framework for the Simultaneous Clearing of Multiple Markets within a Common Transmission System
Marinakis, Adamantios ULg; Rosehart, William; Van Cutsem, Thierry ULg

in Proceedings of the 2009 IEEE PES Power Tech conference (2009, July)

The possibility for market participants to place their bids in all the markets of an interconnection irrespective of where they are physically connected is investigated in this paper. A mechanism is ... [more ▼]

The possibility for market participants to place their bids in all the markets of an interconnection irrespective of where they are physically connected is investigated in this paper. A mechanism is proposed for managing the resulting congestion. It consists in iteratively sharing the transmission line capacities between the different market operators based each time on their present schedules. The algorithm is applied on a small test system. The results are assessed in terms of their property of being Nash equilibria and of their distance of the set of Pareto optimal operating points. [less ▲]

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See detailEstimation of joint contact forces in the equine digit
Noble, Prisca ULg; Collin, Bernard ULg; Denoix, Jean-Marie et al

in ISB proceedings (2009, July)

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See detailManagement et Justice: la mesure de la charge de travail des magistrats.
Delvaux, David ULg

Conference (2009, July)

A considerable number of articles, conferences and other seminars are dedicated to the topic of the “modernization” of Justice. This expansion of debates around judicial management, certainly reflects the ... [more ▼]

A considerable number of articles, conferences and other seminars are dedicated to the topic of the “modernization” of Justice. This expansion of debates around judicial management, certainly reflects the complexity of the stakes related to this process of modernization, and accounts for the difficulties which the reformers of justice must face. This complex process appears resolutely multi dimensional, articulating managerial, legal, economic and social considerations. Much more than a political rhetoric of the change, the process of modernization of courts is characterized by the development of a multitude of tools related to a new reference frame of effectiveness, efficiency and quality. One of these tools, illustrates the stakes and difficulties met by that the reformers of Belgian Justice: an instrument to measure the workload of magistrates. [less ▲]

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See detailA new heuristic approach to deal with discrete variables in optimal power flow computations
Capitanescu, Florin ULg; Wehenkel, Louis ULg

in IEEE Power Tech conference (2009, July)

This paper proposes a new heuristic approach to deal with discrete variables in an optimal power flow (OPF). This approach relies on the first order sensitivity of the objective and inequality constraints ... [more ▼]

This paper proposes a new heuristic approach to deal with discrete variables in an optimal power flow (OPF). This approach relies on the first order sensitivity of the objective and inequality constraints with respect to the discrete variables. The impact of a discrete variable change on the objective and inequality constraints is aggregated into a merit function. The proposed approach searches iteratively for better discrete variable settings as long as the problem solution can be improved. We provide numerical results with the proposed approach on four test systems up to 1203 buses and for the OPF problem of active power loss minimization. [less ▲]

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See detailNew Improvements in the Enantioselective Synthesis of 2-[18F]Fluoro-L-Tyrosine and 6-[18F]Fluoro-L-Dopa
Libert, Lionel ULg; Lemaire, Christian ULg; Denoël, Thibaut ULg et al

in Journal of Labelled Compounds & Radiopharmaceuticals (2009, July), 52(S1), 196

Detailed reference viewed: 52 (14 ULg)
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See detailEquivalent mixed model for joint genetic evaluation considering molecular and phenotypic information
Gengler, Nicolas ULg; Colinet, Frédéric ULg

Conference (2009, July)

Currently efforts are underway to introduce molecular information into genetic evaluation systems. A particular situation is genomic selection however simpler cases exists where major genes are known and ... [more ▼]

Currently efforts are underway to introduce molecular information into genetic evaluation systems. A particular situation is genomic selection however simpler cases exists where major genes are known and used by breeders. A new alternative strategy for the prediction of gene effects and especially their smooth integration into genetic evaluations based on an equivalent method was developed from existing theory. Underlying hypothesis were based on the idea that knowledge of genotypes will not affect overall additive genetic variance but only change expected values of genetic effects for animals with known genotypes. The developed equations were modified to allow that not all animals were genotyped. As the underlying mixed model is open a very large range of models can be used in situations including random regression models, multipletrait, maternal effects and multiple-across-country-evaluation models. Computations involved successive solving of two mixed models, with the use of an linear extrapolation to speed up convergence of gene effects. The method was tested for several known major genes and QTL, e.g. for the mh gene in the dual-purpose Belgian Blue population in Belgium. Modifications of the method could also be developed to be useful in the context of genomic selection. [less ▲]

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See detailCorrelates of personal fluctuation, pseudo-guessing, and inattention subject parameters: relations with parametric and non parametric person fit indices
Béland, Sébastien; Raîche, Gilles; Brassard, Patricia et al

Conference (2009, July)

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See detailMilestones for Teaching the Spreadsheet Program
Vandeput, Etienne ULg

in The Role of Spreadsheets in Organisational Excellence (2009, July)

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See detailOptimal power flow computations with constraints limiting the number of control actions
Capitanescu, Florin ULg; Rosehart, William; Wehenkel, Louis ULg

in IEEE Power Tech conference (2009, July)

This paper focuses on optimal power flow (OPF) computations in which no more than a pre-specified number of controls are allowed to move. The benchmark formulation of this OPF problem constitutes a mixed ... [more ▼]

This paper focuses on optimal power flow (OPF) computations in which no more than a pre-specified number of controls are allowed to move. The benchmark formulation of this OPF problem constitutes a mixed integer nonlinear programming (MINLP) problem. To avoid the prohibitive computational time required by classical MINLP approaches to provide a (potentially sub-optimal) solution, we propose instead two alternative approaches. The first one consists in reformulating the MINLP problem as a mathematical program with equilibrium constraints (MPEC). The second approach includes in the classical OPF problem a nonlinear constraint which approximates the integral constraint limiting the number of control variables movement. Both approaches are solved by an interior point algorithm (IPA), slightly adapted to the particular characteristics of each approach. We provide numerical results with the proposed approaches on two test systems and for two practical problems: minimum cost to remove thermal congestion, and minimum cost of load curtailment to restore a feasible equilibrium point. [less ▲]

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See detailModified Non-Ionic Solid Supports: a Way to High Activity Fluorine-18 Radiochemistry in Microfluidic Devices
Aerts, Joël ULg; Voccia, Samuel; Lemaire, Christian ULg et al

in Journal of Labelled Compounds & Radiopharmaceuticals (2009, July), 52(S1), 12

Detailed reference viewed: 37 (6 ULg)
See detailTime reversal of Bose-Einstein condensates
Martin, John ULg; Georgeot, Bertrand; Shepelyansky, Dima

Poster (2009, July)

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See detailSurgery of urinary bladder tumors
Hamaide, Annick ULg

in Proceedings du 18th Annula Scientific Meeting de l'ECVS (2009, July)

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See detailPerceived logistics service quality driven store Loyalty
Hammedi, Wafa ULg; Van Riel, Allard ULg; Semeijn, Janjaap

Poster (2009, July)

Detailed reference viewed: 101 (12 ULg)
See detailPyropheophorbide-a-methyl ester: DMPC liposome vectorization and biophysical properties for PDT
Guelluy, Pierre-Henri ULg; Fontaine-Aupart, Marie-Pierre; Grammenos, Angeliki ULg et al

Poster (2009, July)

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See detailA Novel Concept for Helicopter Rotor Drives
Antoine, Hubert; Dimitriadis, Grigorios ULg; Hendrick, Patrick et al

in Proceedings of the 3rd European Conference for Aero-Space Sciences (2009, July)

The REDT (Rotor à Entraînement Direct par Turbine – Direct Turbine Driven Rotor) is a new concept for helicopter rotor drives developed by Sagita in Belgium. It works without any mechanical link between ... [more ▼]

The REDT (Rotor à Entraînement Direct par Turbine – Direct Turbine Driven Rotor) is a new concept for helicopter rotor drives developed by Sagita in Belgium. It works without any mechanical link between the engine on one side and the rotor drive on the other side. It uses a fuselage-mounted compressor that powers two contra-rotating rotor-mounted free turbines. These free turbines drive a pair of contrarotating rotors that are fitted with rigid hingeless main rotor blades. This novel rotor drive eliminates the need for either mechanical transmission or a tail rotor. The aim of the REDT concept is to lower the maintenance costs and the accident rate, as well as to extend the flight envelope towards much higher airspeeds compared to classical helicopters. [less ▲]

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See detailFinding miRNAs able to regulate angiogenesis
Pendeville, Helene; Nivelles, Olivier ULg; Malvaux, L. et al

Poster (2009, July)

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See detailUse of Organic Bases for 18F-Fluoride Anion Exchange Elution avoiding the Classical Azeotropic drying Step Before Labeling
Lemaire, Christian ULg; Aerts, Joël ULg; Voccia, Samuel et al

in Journal of Labelled Compounds & Radiopharmaceuticals (2009, July), 52(S1), 198

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See detailA robust statistical approach to differential item functioning
Magis, David ULg; De Boeck, Paul

Conference (2009, July)

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See detailEvolution of floodplain sedimentation during the last millennia in the Ardenne Massif (Belgium)
Houbrechts, Geoffrey ULg; Notebaert, Bastiaan; Verstraeten, Gert et al

Poster (2009, July)

In the Ardenne massif, several periods of increased sediment deposition have been identified during the last millennia. They can be correlated to increasing anthropogenic land use pressure. The majority ... [more ▼]

In the Ardenne massif, several periods of increased sediment deposition have been identified during the last millennia. They can be correlated to increasing anthropogenic land use pressure. The majority of the sediments found in floodplains were deposited in the last 4000 years, and in many cases even in the last 1000 years. In the Amblève catchment, the first increase in sediment deposition of the Holocene occurred during the Bronze Age (3200 BP), related to first deforestations and crop cultures in the area. Several organic depositions have occurred between 2700 BP and 1000 BP and probably indicate low anthropogenic pressures or more humid periods. From the 11th century onwards, there was an increase in sedimentation, and alluvial deposits contain more charcoal. A second important increase in sedimentation is observed in headwater catchments at the end of the 14th century, which can be related to the development of many iron factories. In the Ardenne massif, more than 300 iron factories existed between the 14th and the 19th century and about 20 ha of forest were cleared each year for the consumption of a refining forge or a blast furnace. Analysis of slag concentration produced in former factories and redistributed in the floodplain allows us to reconstruct the evolution of floodplains since the inception of the iron industries. The results show that not all floodplains in the Amblève catchment are equally sensitive to catchment disturbances. In the headwater stream (Chavanne river, 10-20 km²), about 80 cm of sediment has been deposited since the inception of the iron industries (towards 1540 AD). In the lower Lienne valley (100-150 km²), almost no sediment accumulation occurred in the floodplains after the beginning of iron melting (towards 1400 AD). This difference could be explained by the larger stream power of the Lienne river (100-120 W/m2 for Qb). [less ▲]

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See detailMultidimensional fluctuation, pseudo-guessing and carelness IRT person parameters models
Raîche, Gilles; Magis, David ULg; Blais, Jean-Guy

Conference (2009, July)

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See detailVoting at 16: A Study of Political Reasoning Among Young French-Speaking Belgians
Fournier, Bernard ULg; Flaba, Elodie ULg

Conference (2009, July)

The question of lowering the voting age to 16 has long been debated in university circles. In the last Austrian elections, young people aged 16 and older were invited to vote, even if young people ... [more ▼]

The question of lowering the voting age to 16 has long been debated in university circles. In the last Austrian elections, young people aged 16 and older were invited to vote, even if young people themselves are divided over this issue, even hostile to the idea. Nevertheless, isn’t such a question, which is rarely discussed by the larger public and touches on several dimensions of a person’s life, an ideal topic for a debate, where the confrontation of ideas may change opinions and reveal – or even modify – young people’s global attitudes towards political interest and participation? A sample of one hundred 15- to 21-year-old youth in French-speaking Belgium was selected to discuss the possibility of lowering the voting age to 16, as well as political interest and political participation, during one day with five experts. The same questionnaire was filled in in the beginning and at the end of the day. These first results are presented here. They show little evolution during the discussion, in a sample already largely against the idea of lowering the voting age. [less ▲]

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See detailAre Ionic Liquid Useful for Fluorine-18 Labeling?
Aerts, Joël ULg; Lemaire, Christian ULg; Plenevaux, Alain ULg et al

in Journal of Labelled Compounds & Radiopharmaceuticals (2009, July), 52(S1), 193

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See detailTertiary Alcohols to Avoid Evaporation in Fluorine-18 Labeling
Aerts, Joël ULg; Voccia, Samuel; Lemaire, Christian ULg et al

in Journal of Labelled Compounds & Radiopharmaceuticals (2009, July), 52(S1), 204

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See detailAn item ixture model to detect differential item functioning
Frederickx, Sofie; Tuerlinckx, Francis; De Boeck, Paul et al

Conference (2009, July)

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See detailTesting and validation of simulation tools of HVAC mechanical equipment including their control strategies. Part II: Validation of cooling and heating coil models
Felsmann, Clemens; Lebrun, Jean ULg; Lemort, Vincent ULg et al

(2009, July)

This paper presents detailed information about testing and validation of cooling and heating coil models. The work has been carried out under Subtask D of the International Energy Agency’s SHC Task 34 ... [more ▼]

This paper presents detailed information about testing and validation of cooling and heating coil models. The work has been carried out under Subtask D of the International Energy Agency’s SHC Task 34/ECBCS Annex 43 (Testing and Validation of Building Energy Simulation Tools). The goal of this Subtask (Mechanical Equipment and Control Strategies) was to develop and test methods that would help evaluating, diagnosing and correcting HVAC mechanical equipment simulation software. [less ▲]

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See detailInsights into the plant defense mechanisms induced by Bacillus lipopeptides.
Ongena, Marc ULg; Henry, Guillaume ULg; Adam, Akram et al

Poster (2009, July)

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See detailStudy of the bedload transport in gravel bed rivers
Houbrechts, Geoffrey ULg; Hallot, Eric ULg; Peeters, Alexandre ULg et al

Conference (2009, July)

Bedload transport has been studied in Ardenne rivers using different methods. Experiments with marked pebbles were carried out on gravel bed rivers in order to determine critical parameters of ... [more ▼]

Bedload transport has been studied in Ardenne rivers using different methods. Experiments with marked pebbles were carried out on gravel bed rivers in order to determine critical parameters of mobilisation. The tracking of more than 1000 elements marked with PIT-tags (Passive Integrated Transponder) has been performed on different sized rivers during three hydrological seasons. These surveys allowed us to determine the initial motion of bed material, to measure the distance of particle travel from flood to flood, to reconstruct the trajectories of pebbles, to analyze the burying of particles into the subsurface layer and to identify the trapping sites and their effects on the bedload progression. On the same rivers, the thickness of the active bed layer has been measured using scour chains. It appears that the mobilised layer thickness increases with specific stream power. Bedload discharge of several floods has also been estimated crossing the active layer thickness and the mean progression distance of marked pebbles. Pits have been dug across the bed of a gravel bed stream (catchment area of 12 km²) in order to trap all particles moving on the bed. Volume of sediments trapped has been measured after each flood event and the largest elements mobilised have been measured. These observations show that bedload trapped is clearly more important that bedload discharge estimated by the method of scour chains and marked pebbles. This difference is for the most part explained by the trapping of sandy matrix from the subsurface layer, which is also moving on the bed. In this headwater stream (forested floodplain), the specific bedload discharge is only 0.4 t.km-1.year-1. Such a value is relatively low in comparison with other Ardenne rivers (up to 2,5 t.km-1.year-1), but may be partly explained by numerous vegetation logjams, which slow down bedload progression and increase bed roughness. [less ▲]

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See detailA maġribī copy of the Kitāb al-Faraj baʿd aš-Šidda by the ʿIrāqī qāḍī at-Tanūḫī. Study of a University of Liège (Belgium) manuscript
Franssen, Elise ULg

Conference (2009, July)

La collection de manuscrits arabes (et en écriture arabe) de la Bibliothèque Générale de l'Université de Liège est exceptionnelle... et trop peu connue. Un manuscrit particulier est ici présenté. Il s ... [more ▼]

La collection de manuscrits arabes (et en écriture arabe) de la Bibliothèque Générale de l'Université de Liège est exceptionnelle... et trop peu connue. Un manuscrit particulier est ici présenté. Il s'agit d'une copie du XVIe siècle (de notre ère) du Kitāb al-Faraj baʿd aš-Šidda, ouvrage littéraire de l'irakien at-Tanuḫī (327-384 de l'Hégire/939-994 apr. J.C.). Le manuscrit a fait l'objet d'une analyse codicologique et paléographique détaillée, couplée à une analyse philologique du texte, comprenant notamment sa collation avec l'édition critique généralement utilisée. Cette étude a permis de mettre en avant les particularités du manuscrit en tant qu'objet et en tant que texte et de le placer dans la tradition manuscrite maghrébine du XVIe siècle. [less ▲]

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See detailLocal vs. wide-area undervoltage load shedding in the presence of induction motor loads
Otomega, Bogdan; Van Cutsem, Thierry ULg

in Proceedings of the IEEE PES PowerTech 2009 conference (2009, July)

In the presence of induction motor loads, long-term voltage instability may end up in a sharp voltage decrease, which makes the tuning of undervoltage load shedding more delicate. This paper first ... [more ▼]

In the presence of induction motor loads, long-term voltage instability may end up in a sharp voltage decrease, which makes the tuning of undervoltage load shedding more delicate. This paper first investigates the ability of a purely distributed load shedding scheme, previously proposed by the authors, to cope with these situations. Owing to difficulties to reconcile dependability and security, an alternative wide-area protection is considered. The latter consists of generators sending overexcitation signals to the load shedding controllers in order to allow the latter to act faster. Detailed time simulations of a test system are reported. [less ▲]

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See detailLiver transplantation from controlled donation after cardiac death (DCD) donors: a single center experience
Detry, Olivier ULg; Veys, Caroline; Seydel, Benoît ULg et al

in Liver Transplantation (2009, July), 15(7), 180-181

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See detailMeasure of nursing time interventions for hospitalized elderly patients
THONON, Olivier ULg; GILLAIN, Daniel ULg; SERMEUS, Walter et al

Poster (2009, July)

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See detailExtreme increase of CO2 in belgian caves
Ek, Camille ULg; Godissart, Jean

in ICS 2009 Proceedings (2009, July)

We began making CO2 measurements in Belgian caves in 1966. Analyses were conducted in cave halls, galleries, fissures and shafts, in various seasons and at different levels above the floors of the ... [more ▼]

We began making CO2 measurements in Belgian caves in 1966. Analyses were conducted in cave halls, galleries, fissures and shafts, in various seasons and at different levels above the floors of the conduits, and in the absence or presence of other human beings. Our first results were published in 1968. From that time on, we have carried out studies in Poland, Quebec, China and other countries but we have focused most of our work in Belgium. We have discovered over these forty years of study, a strong increase in the observed values of CO2 in Belgian caves. For example, a few of our observations follow. “Trou Joney” (Comblain-au-Pont, province of Liege) is a small and shallow cave. We measured at the central point of the main gallery, 1870 ppm CO2 in July 1966, and 13800 ppm at the same location in July 2007. At the bottom of the shaft of the “Comblain-au Pont” cave, we measured 600 ppm in July 1966 and found 1500 ppm in July 2008. In “La Merveilleuse” cave (Dinant, province of Namur), we measured 800 ppm at the central point of the Big Hall in August 1990, rising to 1700 ppm in August 2008. In the main gallery of the “Fontaine de Rivire” cave (Hamoir, province of Liege), we found 5000 ppm in August 1972, increasing to 9400 ppm in 2008. We conclude that the CO2 content of the atmospheres of many caves in Belgium at least, is very sharply getting higher. The increase is very variable, but omnipresent. Are our measurements significant? We believe that we have validated our instruments and our methods. The increase is probably not a result of local industrial activities. The CO2 curves of Mauna Loa Observatory (Hawaii) and “Mace Head” (Ireland) both show an increase of atmospheric carbon dioxide during the last half century. However, the upsurge of CO2 observed in the caves is much greater than the increase in those well-known surface measurements. There is a very complex interrelationship between temperature, vegetation and biomass activity, and CO2 in the soil and underground. The increase of any one of these three parameters can induce changes in the two others, and hence in the partial pressure of CO2 in cave air. [less ▲]

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See detailPEPTIDE CLICK LABELLING WITH 1-(AZIDOMETHYL)-4-[18F]-FLUOROBENZENE AND REFERENCE COMPOUNDS SYNTHESIS ON SOLID SUPPORT
Thonon, David ULg; Paris, Jérôme ULg; Kech, Cecile et al

in Journal of Labelled Compounds and Radiopharmaceuticals (2009, July)

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See detailLongitudinal analysis of ordinal data
Donneau, Anne-Françoise ULg; Mauer, M

Conference (2009, June 30)

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See detailUn outil d’aide à la décision pour la gestion des chablis en Région wallonne (Belgique)
Riguelle, Simon ULg; Hebert, Jacques ULg; Jourez, Benoît ULg

Poster (2009, June 30)

The poster highlights the main steps leading to the development of a decision-support tool for storm damage management by the forest sector at a regional scale.

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See detailScabies in a llama (Lama glama): control with moxidectin long acting (Cydectin®LA)
Caron, Yannick ULg; Cavadino, Céline; Losson, Bertrand ULg

Poster (2009, June 29)

An adult neutered male llama (Lama glama) was presented for examination with a history of a severe long lasting (3 years) and recurrent itch and crust formation. Three years ago, scabies had been ... [more ▼]

An adult neutered male llama (Lama glama) was presented for examination with a history of a severe long lasting (3 years) and recurrent itch and crust formation. Three years ago, scabies had been diagnosed by a local vet on the basis of clinical signs; the animal was treated several times with ivermectin (Ivomec®) injectable and phoxim (Sarnacuran®). After each treatment there was a marked clinical improvement but relapse was the rule within 1 to 2 months. During the two years preceeding our first visit the animal had received local applications of Sarnacuran every two to three weeks wich resulted in incomplete control. None of the owners had reported skin lesions compatible with scabies. On February 27th 2009 the animal showed a marked pruritus accompanied by very thick scabs and alopecia on the face (around the mouth and ears), shoulders, forelegs, hindlegs, abdomen, flanks and the tail. Clinical examination revealed a fairly good general condition. Abnormalities were limited to the skin. Skin scrapings were taken and numerous Sarcoptes scabiei mites were subsequently detected microscopically. Sedation and analgesia were performed via the intramuscular administration of xylazine (Vexylan®) at 0.5 mg/kg. The scabs were humidified with a camomile infusion and a maximum of material was removed and destroyed. Then the llama was treated with 10% moxidectin (Cydectin LA®) at 1 mg/kg by subcutaneous injection at the basis of the ear. On April 6th 2009, a very marked clinical improvement was observed: most of the scabs had dissapeared and hair regrowth in previously alopecic area was observed. Skin scrapings were negative. However, some pruritus was still observed and a second treatment with Cydectin LA was given. According to the owner who was contacted by phone in early May the clinical condition of the animal has further improved. A final visit is planned to assess the clinical and parasitological cure in this S. scabiei infected llama. At our knowledge, this is the first time Cydecin LA is used in llama for the treatment of scabies. [less ▲]

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See detailQuelles sont les espèces d’oiseaux indicatrices de la qualité des forêts feuillues ardennaises ?
Delahaye, Laurence; Rondeux, Jacques ULg

Poster (2009, June 29)

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See detailDividends and Foreign Performance Signaling
Muller, Aline ULg; Joliet, Robert

Conference (2009, June 29)

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See detailEvaluation de la fonction récréative des massifs forestiers wallons
Colson, Vincent ULg; Lejeune, Philippe ULg; Rondeux, Jacques ULg

Poster (2009, June 29)

Estimer la valeur économique des visites effectuées à des fins récréatives en forêt wallonne.

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See detailActualité des droits communautaire et belge de la concurrence
Petit, Nicolas ULg

Conference (2009, June 29)

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See detailCapital structure effects of international expansion
Muller, Aline ULg; Joliet, Robert

Conference (2009, June 28)

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See detailL’apport des focus groups dans la compréhension des structures de raisonnement quant à la conscientisation accompagnant la transmission des faits génocidaires
Grandjean, Geoffrey ULg

Conference (2009, June 26)

La transmission des faits génocidaires auprès des jeunes générations semble être accompagnée d’une conscientisation favorisant l’adoption par les adolescents de certains comportements ou attitudes. Pour ... [more ▼]

La transmission des faits génocidaires auprès des jeunes générations semble être accompagnée d’une conscientisation favorisant l’adoption par les adolescents de certains comportements ou attitudes. Pour appréhender cette conscientisation, des focus groups ont été réalisés auprès d’adolescents belges francophones (âgés de 16 à 18 ans). Le but était de voir, à travers les discussions, comment ces jeunes ont internalisé la conscientisation accompagnant la transmission des faits génocidaires. Cette communication contribue ainsi au débat méthodologique qui entoure l’utilisation des focus groups dans la recherche en science politique et sociale et plus particulièrement pour saisir les structures de raisonnement de ces jeunes, considérées dans une dynamique sociale. Afin d’illustrer ce propos, quelques résultats sont présentés. [less ▲]

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See detailLa prévention médicalisée est-elle néfaste pour nos patients ? Et à quelles conditions leur serait-elle bénéfique ?
Vanmeerbeek, Marc ULg

Conference (2009, June 25)

En examinant nos pratiques en prévention, il semble nécessaire de mieux asseoir la validité scientifique de nos actes, e.a. en prenant de la distance par rapport aux pressions commerciales. Il serait ... [more ▼]

En examinant nos pratiques en prévention, il semble nécessaire de mieux asseoir la validité scientifique de nos actes, e.a. en prenant de la distance par rapport aux pressions commerciales. Il serait utile de rapprocher la médecine générale et la santé publique, en augmentant la place de la promotion de la santé et ne développant la place du patient. De nouvelles tâches sont à imaginer dans un partenariat multidisciplinaire. [less ▲]

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See detailApplying control volume finite element for modelling direct injection boom spraying flow
El Aissaoui, Abdellah; Lebeau, Frédéric ULg; Destain, Marie-France ULg et al

Conference (2009, June 23)

Assessment of injection lag transport and uniformity of direct injection boom sprayer is an important issue for successful variable rate spraying technology. To estimate the boom lag transport and ... [more ▼]

Assessment of injection lag transport and uniformity of direct injection boom sprayer is an important issue for successful variable rate spraying technology. To estimate the boom lag transport and pressure loss, a numerical model is formulated on the basis of fluid hydrodynamic conservation equations. The software is implemented in visual basic. To solve the pressure – velocities equations, control volume finite element method (CV) is used to delimit elementary volumes of the boom. Linearization of the conservation laws is ensured by considering discrete form of the equations and calculating velocity and pressure step by step throughout the whole boom. The flow behaviour is simulated into a boom section divided into N elementary volumes, each of them including one nozzle. To test the model, three boom diameters (5, 6 and 8 mm) and two chemical viscosities (10-6 and 10-5 m2/s) were used. Experimental trials are carried out on boom having 2.5 m length (5 nozzles) for measuring pressure gradient and lag transport. Results showed that the model can predict the pressure losses and the lag transport accurately (error within 5%) to optimize boom designs. [less ▲]

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See detailOrganoclays prepared in supercritical CO2: implication of onium stability on the properties of PA6 nanocomposites
Naveau, Elodie ULg; Calberg, Cédric ULg; Detrembleur, Christophe ULg et al

Conference (2009, June 23)

The organomodification of layered silicates via our patented supercritical CO2 ion-exchange process, enables the use of a large variety of surfactants, among which phosphonium and ammonium ions of the ... [more ▼]

The organomodification of layered silicates via our patented supercritical CO2 ion-exchange process, enables the use of a large variety of surfactants, among which phosphonium and ammonium ions of the very same structure. The as-obtained organoclays were melt blended with PA6 and the morphology as well as the fire properties of the nanocomposites were studied. With the same degree of nanodispersion, longer ignition times were observed with phosphonium-modified clays compared to ammonium-modified clays. [less ▲]

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See detailSome Remarks on Dominique Pradelle's Lecture: "Does Husserl have a Reducibility Principle?"
Dewalque, Arnaud ULg

Conference (2009, June 23)

Comments on D. Pradelle's lecture (for details, see the attached document).

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See detail‘Dagongzhe’ Write to the magazines: suffering, borders stretching and longings. Dialectics of identification and legitimation
Florence, Eric ULg

Conference (2009, June 23)

‘Dagongzhe’ Write to the magazines: suffering, borders stretching and longings. Dialectics of identification and legitimation. Eric Florence, PhD in Political and Social Sciences, Researcher at the Centre ... [more ▼]

‘Dagongzhe’ Write to the magazines: suffering, borders stretching and longings. Dialectics of identification and legitimation. Eric Florence, PhD in Political and Social Sciences, Researcher at the Centre for Ethnic and Migration Studies, the University of Liege. In this paper, I will look at the different kinds of values that are fostered within articles (diaries, letters, etc.) published in magazines for rural migrant workers. After having detailed the criterion used by editors of these magazines in the process of selecting or rejecting writings sent to them by migrant authors, I will detail three types of narrative modes found in magazines aimed at migrant workers. The first one signals suffering, disillusionment and sometimes irony. The second narrative mode entails claim making by migrant workers which are often backed by editors. I argue that this belongs to what O’Brien calls “contentious politics”. Eventually, the third mode examined in this paper will be thought of as strategic narrative framing on the part of migrant authors. In such framing the pedagogic role of guidance by editors is central I shall stress. But I shall argue at the same time that despite such framing, much of these writings are permeated by a powerful politics of desire and that such politics is particularly hard to analyse. In addition to a qualitative analysis of both published and unpublished writings by migrant workers and editors, I will also confront such writings and the values they convey to the fruit of my ethnographic fieldwork carried out in the Pearl River Delta between 2001 and 200 [less ▲]

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See detailProposed design rules for iron columns reinforced by FRP
Ly, Dong Phuong Lam ULg; Demonceau, Jean-François ULg; Jaspart, Jean-Pierre ULg et al

in Mazzolani, F. M. (Ed.) Protection of historical buildings, Prohitech 09 (2009, June 21)

This paper presents design rules for iron columns under axial compression, strengthened with high modulus carbon fibre reinforced polymer (FRP) sheets. According to experimental and numerical results, it ... [more ▼]

This paper presents design rules for iron columns under axial compression, strengthened with high modulus carbon fibre reinforced polymer (FRP) sheets. According to experimental and numerical results, it is shown that the resistance and stiffness of iron columns can be significantly increased with the use of longitudinal FRP sheets because of the reduction of the column slenderness, but also that transverse FRP sheets should be used to prevent any local buckling of the longitudinal FRP sheets [less ▲]

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See detailFrom "Spirou" and "Tintin" to "Pilote". A French break from the Belgian classicism
Dejasse, Erwin ULg

Conference (2009, June 19)

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See detailProduction of polymer/clay nanocomposite foams with improved fire behaviour using supercritical fluid technology
Urbanczyk, Laetitia ULg; Calberg, Cédric ULg; Detrembleur, Christophe ULg et al

Poster (2009, June 19)

In this study, supercritical CO2 is successfully used as foaming agent to prepare poly(styrene-co-acrylonitrile) (SAN) foams containing a low amount of well-dispersed nanoclay (5wt%). This kind of ... [more ▼]

In this study, supercritical CO2 is successfully used as foaming agent to prepare poly(styrene-co-acrylonitrile) (SAN) foams containing a low amount of well-dispersed nanoclay (5wt%). This kind of nanofiller has an influence both on material cellular morphology and fire property. In fact, SAN foam filled with nanoclay has smaller cells and higher density compared to unfilled foam. Moreover, the nanocomposite foam burns more slowly and without producing any burning droplets, which is highly desirable when considering housing applications. [less ▲]

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See detailThe daughters of family business: Developing a global research agenda
Nelson, Teresa; Constantinidis, Christina ULg

Conference (2009, June 18)

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See detailThe diversity of Clostridial hydrogenases and biohydrogen production
Calusinska, Magdalena ULg; Savichtcheva, Olga; Masset, Julien ULg et al

Poster (2009, June 18)

Molecular hydrogen is a key intermediate in metabolomic interactions of a wide range of microorganisms. Hydrogen is also regarded as a key component in future energy systems as it is a sustainable, clean ... [more ▼]

Molecular hydrogen is a key intermediate in metabolomic interactions of a wide range of microorganisms. Hydrogen is also regarded as a key component in future energy systems as it is a sustainable, clean, and transportable energy carrier. Some microorganisms can produce hydrogen during a reversible reduction of protons to dihydrogen, a reaction which is catalyzed by hydrogenases [1]. Hydrogenases belong to an iron – sulphur protein family, that contains active sites consisting of inorganic sulfide and iron atoms bound to the polypeptide chain. On the basis of their bimetallocenter composition hydrogenases are divided into three main groups, phylogenetically not related: [NiFe] hydrogenases, [Fe] only hydrogenases and ‘metal – free hydrogenases’ which were described in methanogenic Archaea only. [NiFe] hydrogenases, composed of at least two subunits are well characterized and widely distributed between Archaea and Bacteria but only a few representatives of Clostridium possess this type of enzyme. On the other hand, [Fe] only hydrogenases, being usually monomeric enzymes and restricted to Bacteria and a few eukaryotic species are far less described. These proteins, being omnipresent catalysts of many biological reactions, are especially abundant in Clostridia. The physiological function of Clostridial [Fe] only hydrogenases is to dispose under the form of hydrogen, of the excess of reducing power generated during the fermentation of carbohydrates. The unusual diversity of forms of [Fe] only hydrogenases within Clostridia seems to support the central role of this enzyme in cell metabolism and to facilitate the quick adaptation of the host to changing environmental conditions. Moreover, the presence of multiple putative operons encoding for multisubunit [Fe] only hydrogenases in the genomes of sequenced Clostridium spp. is highlighting the need to study the new, not yet described function of these ostensibly simple proteins. In this project, we have focused our effort on the molecular characterization of key enzymes involved in the process of biohydrogen production with a special interest in Clostridium species. By applying molecular techniques on samples from different kinds of bioreactors, we want to select highly productive species in terms of hydrogen generation. We also believe that gene expression profiling will provide new data on the possible function and activity of different hydrogenases involved in the process. The better understanding of hydrogen metabolism is essential for its sustainable production. [less ▲]

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See detailDetecting Triangle Inequality Violations in Internet Coordinate Systems
Kaafar, Mohamed Ali; Cantin, François ULg; Gueye, Cheikh Ahmadou Bamba ULg et al

in Future Networks 2009 (2009, June 18)

Internet Coordinate Systems (ICS) have been proposed as a method for estimating delays between hosts without direct measurement. However, they can only be accurate when the triangle inequality holds for ... [more ▼]

Internet Coordinate Systems (ICS) have been proposed as a method for estimating delays between hosts without direct measurement. However, they can only be accurate when the triangle inequality holds for Internet delays. Actually Triangle Inequality Violations (TIVs) are frequent and are likely to remain a property of the Internet due to routing policies or path inflation. In this paper we propose methods to detect TIVs with high confidence by observing various metrics such as the relative estimation error on the coordinates. Indeed, the detection of TIVs can be used for mitigating their impact on the ICS itself, by excluding some disturbing nodes from clusters running their own ICS, or more generally by improving their neighbor selection mechanism. [less ▲]

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See detailImpact of contamination on empirical and theoretical error
Ruwet, Christel ULg; Haesbroeck, Gentiane ULg

Conference (2009, June 18)

Classification analysis allows to group similar objects into a given number of groups by means of a classification rule. Many classification procedures are available : linear discrimination, logistic ... [more ▼]

Classification analysis allows to group similar objects into a given number of groups by means of a classification rule. Many classification procedures are available : linear discrimination, logistic discrimination, etc. Focus in this poster will be on classification resulting from a clustering analysis. Indeed, among the outputs of classical clustering techniques, a classification rule is provided in order to classify the objects into one of the clusters. More precisely, let F denote the underlying distribution and assume that the generalized kmeans algorithm with penalty function is used to construct the k clusters C1(F), . . . ,Ck(F) with centers T1(F), . . . , Tk(F). When one feels that k true groups are existing among the data, classification might be the main objective of the statistical analysis. Performance of a particular classification technique can be measured by means of an error rate. Depending on the availability of data, two types of error rates may be computed: a theoretical one and a more empirical one. In the first case, the rule is estimated on a training sample with distribution F while the evaluation of the classification performance may be done through a test sample distributed according to a model distribution of interest, Fm say. In the second case, the same data are used to set up the rule and to evaluate the performance. Under contamination, one has to replace the distribution F of the training sample by a contaminated one, F(eps) say (where eps corresponds to the fraction of contamination). In that case, thetheoretical error rate will be corrupted since it relies on a contaminated rule but it may still consider a test sample distributed according to the model distribution. The empirical error rate will be affected twice: via the rule and also via the sample used for the evaluation of the classification performance. To measure the robustness of classification based on clustering, influence functions of the error rate may be computed. The idea has already been exploited by Croux et al (2008) and Croux et al (2008) in the context of linear and logistic discrimination. In the computation of influence functions, the contaminated distribution takes the form F(eps) = (1 − eps)*Fm + eps* Dx, where Dx is the Dirac distribution putting all its mass at x. It is interesting to note that the impact of the point mass x may be positive, i.e. may decrease the error rate, when the data at hand is used to evaluate the error. [less ▲]

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See detailNew fluorinated surfactants for nanogels preparation
Alaimo, David ULg; Rieger, Jutta; Beigbeder, Alexandre et al

Conference (2009, June 18)

A series of novel fluorinated amphiphilic stabilizers of different architecture (diblock, grafted, or palm tree copolymers) were successfully prepared by reversible addition-fragmentation chain transfer ... [more ▼]

A series of novel fluorinated amphiphilic stabilizers of different architecture (diblock, grafted, or palm tree copolymers) were successfully prepared by reversible addition-fragmentation chain transfer and used as stabilizers for the dispersion polymerization of 2-hydroxyethyl methacrylate (HEMA) in fluorinated solvent, namely alpha,alpha,alpha-trifluorotoluene (TFT). The effect of the amount and the architecture of the copolymer on the size and the stabilization of the particles was studied. Whatever the experimental conditions, scanning electron microscopy showed the formation of submicronic (typically about 300 nm) spherical particles, with a narrow size distribution. The principal difference emerges from the concentration of surfactant. Indeed, at higher copolymer concentration, smaller and less aggregated particles were produced. These results were confirmed by dynamic light scattering but these measurements also revealed the presence of larger aggregates (1,5 micrometer). Furthermore, the surfactant properties of the copolymers were investigated by measuring the interfacial tension at the H2O/TFT interface, and the results were correlated to their stabilizing efficiency in the dispersion polymerization of HEMA. [less ▲]

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See detailLa réception de l'approche law & economics par les juristes
Sibony, Anne-Lise ULg

Conference (2009, June 16)

Detailed reference viewed: 35 (1 ULg)
See detailMyopia, redistribution and pensions
Pestieau, Pierre ULg

Conference (2009, June 15)

Detailed reference viewed: 9 (0 ULg)
See detailEDLC electrodes from cellulose-based carbon aerogels : influence of the carbon's surface chemistry
Hildenbrand, Claudia; Grzyb, B.; Berthon-Fabry, S. et al

Poster (2009, June 14)

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See detailCarbon xerogels as supports for catalysts and electrocatalysts
Job, Nathalie ULg; Berthon-Fabry, S.; Lambert, Stéphanie ULg et al

Conference (2009, June 14)

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See detailNovel Amphiphilic copolymers and design of smart nanoparticule for triggered drug delivery systems
Cajot, Sébastien ULg; Jérôme, Christine ULg

Poster (2009, June 14)

Over the last decade, polymer micelles attracted an increasing interest in drug pharmaceutical research because they could be used as efficient drug delivery systems. Micelles of amphiphilic block ... [more ▼]

Over the last decade, polymer micelles attracted an increasing interest in drug pharmaceutical research because they could be used as efficient drug delivery systems. Micelles of amphiphilic block copolymers are supramolecular core-shell type assemblies of tens of nanometers in diameter. In principle, the micelles core is usually constructed with biodegradable hydrophobic polymers such as aliphatic polyesters, e.g. poly(epsilon-caprolactone) (PCL), which serves as a reservoir for the incorporation of various lipophilic drugs. Water soluble poly(ethylene oxide) (PEO) is most frequently used to build the micelle corona because it is very efficient in preventing protein adsorption at surfaces and in stabilizing the micelles in the blood compartment, giving rise to particles invisible to the body defence system (so-called stealthy or long circulating particles). Improvements of such simple systems however, rely on the development of novel chemistries and materials by advanced macromolecular engineering techniques. The tumour targeting of a cytotoxic agent refers to the passive accumulation of polymer nanocarriers to solid tumours (EPR effect) followed by active internalization in tumor cells. The internalization of the drug is required for cell death because most cytotoxic drugs act intracellularly. Accordingly, polymer micelles are usually modified by specific ligands. However, these ligands can decrease the micelles stealthiness and stability. No-specific ligands can be used if their exposition is modulated by the pH decrease typical of tumour tissues. Lipophilic drugs are generally incorporated in the hydrophobic core of the micelles. The release of the drug is ruled by diffusion and degradation of the biodegradable polymer used as reservoir. Even if micelles get a high stability in aqueous media thanks to their low critical micellar concentration, the dissociation of micelles is not always preserved when they are injected in the blood compartment. The cross-linking of the core of micelles by disulfide bridges will provide the stability of micelles after the administration and will release the drugs intracellularly by enzymatic breaking of disulfide bridges. This work consists in the development of new macromolecular architectures for the targeting of tumour cells. pH sensitive copolymers able to micellize so as non-specific ligand like biotin is exposed on their surface in response to pH decrease typical for tumour tissues will be synthesized by the incorporation of pH-sensitive linkers like hydrazone or imine benzoïc linkers. In addition, the core of these new micelles will be cross-linked by disulfide bridges to prevent dissociation around healthy cells and trigger the drug release inside tumour cells. [less ▲]

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See detailDevelopment of multilayered chitosan-based nanofibers
Croisier, Florence ULg; Aqil, Abdelhafid ULg; Detrembleur, Christophe ULg et al

Poster (2009, June 14)

By combining electrospinning and layer-by-layer deposition techniques, new porous material scaffolds of multilayered, chitosan-based nanofibers were produced. Layer-by-layer (LBL) is a well-known method ... [more ▼]

By combining electrospinning and layer-by-layer deposition techniques, new porous material scaffolds of multilayered, chitosan-based nanofibers were produced. Layer-by-layer (LBL) is a well-known method for surface coating, based on electrostatic interactions. It enables the controllable deposition of a variety of polyelectrolytes including synthetic and natural materials, with designable layer structure, defined layer thickness and size. Electrospinning (ESP) allows the fabrication of polymer fibers ranging from nanometers to a few microns in diameter, depending on the polymer characteristics (a.o. molecular weight, solution viscosity and conductivity) and processing conditions (electric potential, distance between syringe-capillary and collection plate, concentration, flow rate). Mats of nanofibers produced by ESP display a very large surface area-to-volume ratio and high porosity with very small pore size. The nanometric scale of electrospun fibers also proves a positive effect on cellular growth, as fiber mats mimic extracellular matrix structure. The association of these two techniques with the use of biocompatible and biodegradable polymers such as chitosan, gives outstanding prospects in the field of biomedical applications, especially for the preparation of wound dressings, artificial skin or tissue engineering scaffolds. In the present study, a charged copolymer, poly(methylmethacrylate-block-methacrylic acid), was added to a poly(ε-caprolactone) or poly(D,L-lactide) solution before electrospinning in order to prepare surface charged nanofibers. Oppositely charged polyelectrolytes – chitosan and poly(styrene sulfonate) or hyaluronic acid – were then alternately deposited on these aliphatic polyester fiber “cores” using LBL method. The aliphatic polyester core was also removed selectively to confirm the growth of a multilayered shell, obtaining hollow fibers. [less ▲]

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See detailDesign of thermoresponsive magnetic nanoparticles for hyperthermia
Sibret, Pierre ULg; Aqil, Abdelhafid; Jérôme, Christine ULg

Poster (2009, June 14)

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See detailEvolution of the surface chemistry of carbon xerogels with very different textural properties by chemical activation and oxidation
Zubizarreta, Leire; Arenillas, A.; Pirard, Jean-Paul ULg et al

Poster (2009, June 14)

Detailed reference viewed: 20 (1 ULg)