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See detailThe system of kallikrein-kininogens-kinins (KKK) and the acute-phase reactant proteins (APRP) in human undergoing extracorporeal circulation (ECC)
Faymonville, Marie ULg; Adam, A.; Malengreaux, P. et al

in Arnaud, P.; Bienvenu, J.; Laurent, P. (Eds.) Marker proteins in inflammation (1984)

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See detailSystem optimization for residential SOFC 5 kW heat and electricity management
Lilien, Jean-Louis ULg; Lerson, Sébastien; Pochet, Nicolas

(2004, July)

A demonstration project will be presented using a 5 kW Solid Oxyde Fuel Cell for residential application in the region of Liège, Belgium. The current stage of the project is to evaluate the thermal ... [more ▼]

A demonstration project will be presented using a 5 kW Solid Oxyde Fuel Cell for residential application in the region of Liège, Belgium. The current stage of the project is to evaluate the thermal management of a single house with, at the present time, 45 MW.h (thermal 25 MW.h, electrical 20 MW.h) annual consumptions. The changes needed from a classical gas boiler heating of 20 kW to a 6 kW (thermal) plus 5 kW (electrical) system will be studied and detailed. Evaluation of CO2 reduction in the two systems will be presented considering the Belgium mix of electricity production. The heat and electricity local storage to cover peak demand in both energy demands will be discussed in relation with a grid-connected fuel cell. In particular the detailed analysis of this home demand will be analysed for the last three years. An original thermal circuit will be proposed, including its regulation. The experimental result of the behaviour of our proposal during 2003-2004 winter will be presented using a “virtual” SOFC (actually replaced by “equivalent” 6 kWth boiler) which is intended to be used in the same environment after this testing period. Constrains related to SOFC typical behaviour will be taken into account in our proposal for regulation. Depending on our development, it may be possible that up-to-date results may be given at the conference with a real system using a true SOFC 5 kW which would be in service after Septembre 2004. [less ▲]

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See detailSystem overview of the VLTI Spectro-Imager
Jocou, L.; Berger, J.-P.; Malbet, F. et al

in Schöller, Markus; Danchi, William; Delplancke, Françoise (Eds.) Optical and Infrared Interferometry (2008, July 01)

The VLTI Spectro Imager project aims to perform imaging with a temporal resolution of 1 night and with a maximum angular resolution of 1 milliarcsecond, making best use of the Very Large Telescope ... [more ▼]

The VLTI Spectro Imager project aims to perform imaging with a temporal resolution of 1 night and with a maximum angular resolution of 1 milliarcsecond, making best use of the Very Large Telescope Interferometer capabilities. To fulfill the scientific goals (see Garcia et. al.), the system requirements are: a) combining 4 to 6 beams; b) working in spectral bands J, H and K; c) spectral resolution from R= 100 to 12000; and d) internal fringe tracking on-axis, or off-axis when associated to the PRIMA dual-beam facility. The concept of VSI consists on 6 sub-systems: a common path distributing the light between the fringe tracker and the scientific instrument, the fringe tracker ensuring the co-phasing of the array, the scientific instrument delivering the interferometric observables and a calibration tool providing sources for internal alignment and interferometric calibrations. The two remaining sub-systems are the control system and the observation support software dedicated to the reduction of the interferometric data. This paper presents the global concept of VSI science path including the common path, the scientific instrument and the calibration tool. The scientific combination using a set of integrated optics multi-way beam combiners to provide high-stability visibility and closure phase measurements are also described. Finally we will address the performance budget of the global VSI instrument. The fringe tracker and scientific spectrograph will be shortly described. [less ▲]

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See detailA system-level modal description of flexible multibody dynamics
Heirman, Gert H.K; Bruls, Olivier ULg; Desmet, Wim

in Proceedings of the 9th National Congress on Theoretical and Applied Mechanics (2009, May)

Current modelling techniques only allow realtime simulation of strongly simplified models of flexible mechanisms. Both the number of degrees of freedom needed to accurately describe flexibility as the DAE ... [more ▼]

Current modelling techniques only allow realtime simulation of strongly simplified models of flexible mechanisms. Both the number of degrees of freedom needed to accurately describe flexibility as the DAE-character of the system equations limit the computational efficiency. Bodylevel model reduction such modal synthesis is typically used to decrease the computational load of a simulation, but this cannot fully meet the demands for real-time simulation of flexible mechanisms. In this research, Global Modal Parametrization, a model reduction technique initially proposed for controller design for flexible mechanisms, is further developed to speed up simulation of multibody systems. The reduction is achieved by a system-level modal description, as opposed to the classic body-level modal description. As the dynamics is configuration-dependent, the systemlevel modal description is chosen configuration-dependent in such a way that the system dynamics is optimally described with a minimal number of degrees of freedom. Another novelty is GMP-based simulation. In a numerical experiment, simulation results for the original model equations are compared with simulation results for the model equations obtained after model reduction, showing a good match. The approximation errors resulting from the model reduction techniques are investigated by comparing results for different mode sets. The mode set affects the approximation error similarly as it does in linear modal synthesis. [less ▲]

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See detailA system-level model reduction technique for efficient simulation of flexible multibody dynamics
Heirman, Gert H.K; Bruls, Olivier ULg; Desmet, Wim

in Proceedings of the Multibody Dynamics ECCOMAS Conference (2009, June)

In flexible multibody dynamics, body-level model reduction is typically used to decrease the computational load of a simulation. Body-level model reduction is generally performed by means of Component ... [more ▼]

In flexible multibody dynamics, body-level model reduction is typically used to decrease the computational load of a simulation. Body-level model reduction is generally performed by means of Component Mode Synthesis. This offers an acceptable solution for many applications, but does not result in significant model reduction for systems with moving connection points, e.g. due to a flexible sliding joint. In this research, Global Modal Parametrization, a model reduction technique initially proposed for real-time control of flexible mechanisms, is further developed to speed up simulation of multibody systems. The reduction is achieved by a system-level modal description, as opposed to the classic body-level modal description. As the dynamics is configuration-dependent, the system-level modal description is chosen configuration-dependent in such a way that the system dynamics are optimally described with a minimal number of degrees of freedom. Moving connection points do not pose a problem to the proposed model reduction methodology. The complexity of simulation of the reduced model equations is estimated. The applicability to systems with moving connection points is highlighted. In a numerical experiment, simulation results for the original model equations are compared with simulation results for the model equations obtained after model reduction, showing a good match. The approximation errors resulting from the model reduction techniques are investigated by comparing results for different mode sets. The mode set affects the approximation error similarly as it does in linear modal synthesis. [less ▲]

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See detailSystematic characterization of oil-in-water emulsions for formulation design
Roland, Isabelle ULg; Piel, Géraldine ULg; Delattre, Luc ULg et al

in International Journal of Pharmaceutics (2003), 263(1-2), 85-94

Oil-in-water emulsions varying in surfactant concentration and manufacturing process were prepared. About 10 experiments were performed to characterize them. The goal of this research was to find Out ... [more ▼]

Oil-in-water emulsions varying in surfactant concentration and manufacturing process were prepared. About 10 experiments were performed to characterize them. The goal of this research was to find Out which tests should systematically be carried Out to assess efficiently the stability and the properties of ail emulsified preparation. Thus, formulation design requires at least the measurement of the droplet size, the determination of the zeta potential, a TurbiScan(R) analysis, the investigation of the stability under centrifugation and freeze/thaw cycles. If the emulsion contains an active substance, stability under storage at 4 degreesC and microscopic analysis are relevant. Quality Control Should be improved by measurements of viscosity and pH. (C) 2003 Elsevier B.V. All rights reserved. [less ▲]

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See detailSystematic chromosomal aberrations found in murine bone marrow-derived mesenchymal stem cells.
Josse, Claire ULg; Schoemans, R.; Niessen, Neville-Andrew ULg et al

in Stem Cells & Development (2010), 19(8), 1167-1173

Mesenchymal stem cells (MSCs) are studied as a cellular source for the treatment of various diseases. In this work, we isolated and cultivated murine bone marrow-derived MSCs. After a first observation of ... [more ▼]

Mesenchymal stem cells (MSCs) are studied as a cellular source for the treatment of various diseases. In this work, we isolated and cultivated murine bone marrow-derived MSCs. After a first observation of a solid tumour in a mouse injected with these cells, we systematically explored their chromosomal stability. We observed in all the cytogenetically analysed cases gross chromosomal alterations every time the MSCs went through the senescence crisis while the lymphocytes from the same animals showed a normal chromosome count. This observation was confirmed in different mouse strains, with different culture protocols, and even in short-term cultures after an hematopoietic cell negative immunodepletion performed in order to accelerate the isolation procedure. Therefore, we conclude that murine MSCs display high chromosomal instability, can generate tumours, and that care must be taken before using them for the evaluation of MSC therapeutic potential. [less ▲]

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See detailSystematic Color Transformation Effects in Stromgren Photometry
Manfroid, Jean ULg; Sterken, C.

in Precision Photometry: Astrophysics of the Galaxy (1991)

Not Available

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See detailSystematic color transformation effects in Stromgren photometry
Manfroid, Jean ULg; Sterken, C.

in Astronomy and Astrophysics (1992), 258

A major cause of errors in photometry is to be attributed to the color transformation. A thorough analysis of numerous observing runs carried out in the Stromgren system shows how reliable are the ... [more ▼]

A major cause of errors in photometry is to be attributed to the color transformation. A thorough analysis of numerous observing runs carried out in the Stromgren system shows how reliable are the transformations in the different indices. Conclusions are drawn about the reduction methods, the validity of homogenization procedures, and the choice of the standard stars which define the system. [less ▲]

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See detailSystematic Cooperation in P2P Grids
Briquet, Cyril ULg

Doctoral thesis (2008)

P2P Grid computing seeks the convergence of Grid and P2P technologies. Deploying a P2P Grid middleware on a set of computers enables an organization to automatically barter computing time with other ... [more ▼]

P2P Grid computing seeks the convergence of Grid and P2P technologies. Deploying a P2P Grid middleware on a set of computers enables an organization to automatically barter computing time with other Internet-connected organizations. Such P2P exchanges of computing time enable individual Peers, i.e. organizations, to transparently aggregate large amounts of computational power with minimal infrastructure requirements or administrative cost. Challenges arise from the requirement for scalability and robustness. Individual worker nodes are unreliable, as P2P Grids operate on unmanaged desktop computers. A specificity of P2P Grids is that each Peer can reclaim at any time the computational power of worker nodes supplied to other Peers, leading to bursts of execution preemption. These are the major contributions of our dissertation: * Firstly, we propose a new P2P Grid architecture, the Lightweight Bartering Grid (LBG). Through systematic cooperation between Grid nodes, the reliability of execution of computational requests is greater than the sum of the reliabilities of worker nodes. * Secondly, we propose a highly scalable data transfer architecture. It is based both on the BitTorrent P2P file sharing protocol and on the removal of the temporal cost of downloading redundant copies of input data files. * Thirdly, besides a middleware implementation of LBG, we also provide an implementation of a discrete-event simulator. Its originality resides in the weaving of the simulator code into the bartering code of the middleware, which is made possible through the virtualization of Grid nodes. This enables reproducible testing and accurate performance evaluation of the bartering policies because the Peers of a simulated Grid make the same bartering decisions as Peers deployed on real computers. The LBG architecture exhibits the following remarkable features: * The scheduling model supports the queueing of external requests and the architecture enables a flexible study of bartering policies. * The architecture is open, flexible, lightweight and facilitates software engineering. It enables the easy development, testing, evaluation and deployment of combinations of scheduling policies. * The architecture is fully P2P. [less ▲]

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See detailSystematic expression profiling of Hox genes in the central nervous system of adult mouse
Theys, Nicolas; Doshishti-Agolli, Konstantin; Coste, Cécile ULg et al

Poster (2011, September)

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See detailSystematic InSAR monitoring of African active volcanic zones: What we have learned in three years, or an harvest beyond our expectations
Oreye, N.; Fernandez; Gonzalez, P. et al

in Proc. of 2008 Second workshop on USE of Remote Sensing techniques for Monitoring Volcanoes and Seismogenic Areas, Naples, Italy, 11-24 November 2008, doi: 10.1109/USEREST.2008.4740361 (2008)

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See detailA systematic model reduction method for the control of flexible multibody systems
Bruls, Olivier ULg; Duysinx, Pierre ULg; Golinval, Jean-Claude ULg

in Proc. of the 21st Int. Congress of Theoretical and Applied Mechanics (ICTAM) (2004, August)

This paper presents a method to build closed-form dynamic equations for flexible multibody systems with a minimal kinematic description. Relying on the Finite Element formalism, the method is able to ... [more ▼]

This paper presents a method to build closed-form dynamic equations for flexible multibody systems with a minimal kinematic description. Relying on the Finite Element formalism, the method is able to tackle complex topologies with closed-loops in a systematic way. Thus, it will be of great use in the framework of model based control of flexible mechanisms. The reduction procedure is based on an interpolation strategy: a Finite Element model is built and reduced for a number of selected points in the configuration space, and then, a piecewise polynomial model is adjusted to match the collected data. A few applications of the reduction method are considered: a serial pick-and-place machine, a flexible four bar mechanism, and a parallel kinematic manipulator. [less ▲]

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See detailA Systematic NMR Determination of α-D-Glucooligosaccharides, Effect of Linkage Type, Anomeric Configuration and Combination of Different Linkages Type on 13C Chemical Shifts for the Determination of Unknown Isomaltooligosaccharides
Goffin, Dorothée ULg; Bistricky, Peter; Shashkov, Alexander et al

in Bulletin of the Korean Chemical Society (2009), 30(11), 2535-2541

Prebiotic isomaltooligosaccharide preparations contain α-D-glucooligosaccharides comprising isomaltooligosaccharides (IMOs) and non-prebiotic maltooligosaccharides (MOs). They are both glucose ... [more ▼]

Prebiotic isomaltooligosaccharide preparations contain α-D-glucooligosaccharides comprising isomaltooligosaccharides (IMOs) and non-prebiotic maltooligosaccharides (MOs). They are both glucose oligosaccharides characterized by their degree of polymerization (DP) value (from 2 to ~10), linkage types and positions (IMOs: α-(12, 3, 6 and in a lower proportion internal 14) linkages, Mos: -(14) linkages). Their structure is the key factor for their prebiotic potential. In order to determine and elucidate the exact structure of unknown IMOs and Mos, unambiguous assignments of 13C and 1H chemical shifts of commercial standards, representative of IMOs and Mos diversity, have been determined using optimized standard one and two-dimensional experiments such as 1H NMR, 13C NMR, APT and 1H-1H COSY, TOCSY, NOESY and 1H-13C heteronuclear HSQC, HSQC-TOCSY, and HMBC. Here we point out the differential effect of substitution by a glucose residue at different positions on chemical shifts of anomeric as well as ring carbons together with the effect of the reducing end configuration for low DP oligosaccharides and diasteroisotopic effect for H-6 protons. From this study, structural 13C specific spectral features can be identified as tools for structural analysis of isomaltooligosaccharides. [less ▲]

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See detailA systematic procedure to predict flows induced by major dysfunctions on complexes or cascades of dams
Dewals, Benjamin ULg; Archambeau, Pierre ULg; Erpicum, Sébastien ULg et al

in Proceedings of the 3rd IAHR-International Symposium on Hydraulic Structures (2008)

Hazard analysis of dams arranged in complex or in cascade may involve the assessment of a large number of different scenarios of combined failures. However, a tremendous computation time would be needed ... [more ▼]

Hazard analysis of dams arranged in complex or in cascade may involve the assessment of a large number of different scenarios of combined failures. However, a tremendous computation time would be needed to perform a detailed modeling of the flows generated by all possible scenarios. Therefore, the present paper describes a rational methodology for analyzing the flows induced by the most relevant incidents occurring on a complex or in a cascade of dams and reservoirs. The methodology combines several hydrodynamic models, including the twodimensional flow solver WOLF 2D and a simplified lumped hydrodynamic model, to simulate (i) the flows induced on the dams complex, (ii) the potential breaching in cascade of other dams, as well as (iii) the propagation of the flood wave in the whole downstream valley. The application of the methodology to a practical case study involving a complex of five dams is also described. [less ▲]

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See detailSystematic processing of β – tricalcium phosphate for efficient protein loading and in vitro analysis of antigen uptake
Ozhukil Kollath, Vinayaraj ULg; De Geest, Bruno; Mullens, Steven et al

in Advanced Engineering Materials (2013), 15(4), 295-301

Microparticulate calcium phosphate (CaP) powders are promising drug carriers because of their biocompatibility and degradability under physiological conditions. The adsorption capability of CaP ... [more ▼]

Microparticulate calcium phosphate (CaP) powders are promising drug carriers because of their biocompatibility and degradability under physiological conditions. The adsorption capability of CaP microparticles makes them interesting candidates, within the inorganic carrier materials, for delivering protein antigens to professional antigen presenting cells (APC) for vaccination purpose. However, in order to bind and deliver a sufficient amount of protein, the challenge is to effectively increase the binding capacity of this material. In this study, b-tricalcium phosphate (b-TCP) powder is engineered to obtain microparticles with increased protein loading, using bovine serum albumin as a model antigen. The decrease in particle size and increase in specific surface area of carrier is shown to strongly affect protein adsorption. Finally, we demonstrate that the processed b-TCP is capable of delivering its protein payload in vitro to dendritic cells, which are professional APCs and the target cell population for microparticulate vaccines. [less ▲]

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See detailSystematic regularization of linear inverse solutions of the EEG source localization problem
Phillips, Christophe ULg; Rugg, Michael D; Friston, Karl J

in NeuroImage (2002), 17(1), 287-301

Distributed linear solutions of the EEG source localization problem are used routinely. Here we describe an approach based on the weighted minimum norm method that imposes constraints using anatomical and ... [more ▼]

Distributed linear solutions of the EEG source localization problem are used routinely. Here we describe an approach based on the weighted minimum norm method that imposes constraints using anatomical and physiological information derived from other imaging modalities to regularize the solution. In this approach the hyperparameters controlling the degree of regularization are estimated using restricted maximum likelihood (ReML). EEG data are always contaminated by noise, e.g., exogenous noise and background brain activity. The conditional expectation of the source distribution, given the data, is attained by carefully balancing the minimization of the residuals induced by noise and the improbability of the estimates as determined by their priors. This balance is specified by hyperparameters that control the relative importance of fitting and conforming to prior constraints. Here we introduce a systematic approach to this regularization problem, in the context of a linear observation model we have described previously. In this model, basis functions are extracted to reduce the solution space a priori in the spatial and temporal domains. The basis sets are motivated by knowledge of the evoked EEG response and information theory. In this paper we focus on an iterative "expectation-maximization" procedure to jointly estimate the conditional expectation of the source distribution and the ReML hyperparameters on which this solution rests. We used simulated data mixed with real EEG noise to explore the behavior of the approach with various source locations, priors, and noise levels. The results enabled us to conclude: M Solutions in the space of informed basis functions have a high face and construct validity, in relation to conventional analyses. (ii) The hyperparameters controlling the degree of regularization vary largely with source geometry and noise. The second conclusion speaks to the usefulness of using adaptative ReML hyperparameter estimates. (C) 2002 Elsevier Science (USA). [less ▲]

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See detailSystematic review of efficacy of nutraceuticals to alleviate clinical signs of osteoarthritis.
Vandeweerd, Jean-Michel ULg; Coisnon, C.; Clegg, P. et al

in Journal of Veterinary Internal Medicine (2012), 26(3), 448-56

BACKGROUND: Various treatments of osteoarthritis (OA) have been described, including use of nutraceuticals. OBJECTIVES: To review systematically the literature about the effects of nutraceuticals on ... [more ▼]

BACKGROUND: Various treatments of osteoarthritis (OA) have been described, including use of nutraceuticals. OBJECTIVES: To review systematically the literature about the effects of nutraceuticals on clinical signs of pain or abnormal locomotion in horses, dogs, and cats, and to discuss methodological aspects of trials and systematic reviews. METHODS: A systematic search of controlled trials evaluating the impact of nutraceuticals on OA in horses, dogs, and cats was performed, using Medline, CAB Abstracts, and Google Scholar. Scientific evidence was evaluated by means of criteria proposed by the Food and Drug Administration (FDA), and a scoring system adapted from both the CONsolidated Standards of Reporting Trials (CONSORT) statement and recommendations for assessing trials by the Center of Evidence Based Medicine of Oxford. RESULTS: Twenty-two papers were selected and reviewed, with 5 studies performed in horses, 16 in dogs, and 1 in cats. The strength of evidence was low for all nutraceuticals except for omega-3 fatty acid in dogs. There were limited numbers of rigorous randomized controlled trials and of participants in clinical trials. CONCLUSIONS AND CLINICAL IMPORTANCE: The evidence of efficacy of nutraceuticals is poor, with the exception of diets supplemented with omega-3 fatty acids in dogs. Greater access to systematic reviews must be part of the objectives of the veterinary science in the future. Their reporting would be improved by internationally agreed-upon criteria for standards and guidelines. [less ▲]

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