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See detailThe application of spatial autocorrelation methods to the study of Calluna vulgaris population genetics
Mahy, Grégory ULg; Néve, Gabriel

in Belgian Journal of Botany (1997), 129

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See detailApplication of stable isotopes in trophic ecology: importance of TEF and seasonal baseline for robust interpretations.
Remy, François ULg; Darchambeau, François ULg; Dauby, Patrick ULg et al

Conference (2015, April 02)

Nitrogen, carbon and sulfur stable isotopes are very powerful tools for trophic ecologists to delineate food webs of various ecosystems. More recently… the use of mixing models has exponentially increased ... [more ▼]

Nitrogen, carbon and sulfur stable isotopes are very powerful tools for trophic ecologists to delineate food webs of various ecosystems. More recently… the use of mixing models has exponentially increased to give a more specific vision of organism’s diets and trophic relationships. Two case studies will be presented to give a summary of what’s been done in Liège Oceanology Lab to improve our interpretation of stable isotopes results. First is an experimental calculation of the Trophic Enrichment Factors (TEFs) for one dominant detritivorous species of Mediterranean amphipod inhabiting seagrass detritus: Gammarus aequicauda (Martynov, 1931). This experimental study was planned after a strange result of the SAIR mixing model, giving results opposed to all observations and knowledge we had about this species. Thus, the impact of 3 very different food sources (amphipod powder, algae power, seagrass powder) on the turnover rate of C and N isotopic compositions was tested, and afterwards TEFs for C and N for each source were calculated. Animal food source showed to be the most effectively assimilated with a fast turnover rate while seagrass and algae showed very slow assimilation. TEFs calculations showed to be interesting because TEFs seem not to depend on the natural feeding type of the invertebrate but more on the type of food source. Animal source showed carnivorous TEFs values while seagrass and algae source showed typical detritivorous values. SIAR results with these new custom values gave more coherent values highlighting the major importance of TEFs values for mixing models data interpretation. Second is a simple question: are the seasonal isotopic composition variations observed for many seagrass detritus macrofauna species due to actual diet changes, or only to isotopic baseline shift of the food sources? Macrofauna and all potential food sources were sampled near STARESO Oceanographic Station (Corsica, 8°45’E; 42°35’N) in 2011-2012 at each season at two different sites. SIBER software runs with C and N isotopic data showed spatio-temporal isotopic variations at community, interspecific and intraspecific level. SIBER did not gave us information about the origin of these changes, but coupled with SIAR and our custom TEFs, species actually showing drastic changes of diet were identified, while others seem to reflect more a source baseline isotopic composition shift. Working at specific level is compulsory for fine conclusions. These two case studies highlight the importance of mixing model use and of accurate TEF values to run these models properly to draw robust and reliable conclusions using stable isotopic data. [less ▲]

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See detailApplication of Steam Explosion as Pretreatment on Lignocellulosic Material: A Review
Jacquet, Nicolas ULg; Maniet, Guillaume ULg; Vanderghem, Caroline ULg et al

in Industrial & Engineering Chemistry Research (2015), 54(10), 2593-2598

Steam explosion is a thermo-mechanicochemical pretreatment which allows the breakdown of lignocellulosic structural components by the action of heating, formation of organic acids during the process, and ... [more ▼]

Steam explosion is a thermo-mechanicochemical pretreatment which allows the breakdown of lignocellulosic structural components by the action of heating, formation of organic acids during the process, and shearing forces resulting in the expansion of the moisture. Two distinct stages compose the steam-explosion process: vapocracking and explosive decompression which include modification of the material components: hydrolysis of hemicellulosic components (mono- and oligosaccharides released), modification of the chemical structure of lignin, and modification of the cellulose crystallinity index, etc. These effects allow the opening of lignocellulosic structures and influence the enzymatic hydrolysis yield of the material. [less ▲]

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See detailApplication of sucrose synthase from rice grains for the synthesis of carbohydrates.
Elling, Lothar; Grothus, Marita; Zervosen, Astrid ULg et al

in Annals of the New York Academy of Sciences (1995), 750

The enzymatic synthesis of oligosaccharides offers an efficient way to obtain regiospecific and stereo-selective natural and nonnatural target molecules. However, the very expensive activated sugars are ... [more ▼]

The enzymatic synthesis of oligosaccharides offers an efficient way to obtain regiospecific and stereo-selective natural and nonnatural target molecules. However, the very expensive activated sugars are required as substrates for glycosyltransferases. Activated sugars are usually synthesized by pyrophosphorylases from nucleoside triphosphates and sugar-l-phosphates.'.* For cyclic in situ regeneration, at least three enzymes are needed, which makes the synthesis of, for example, N-acetyllactosamine very complex by established procedure. We report here on the enzymatic synthesis of saccharides and activated sugars by the plant glycosyltransferase sucrose synthase (EC 2.4.1.13)! The glycosyltransferase has the unique feature of catalyzing in vitro the synthesis and cleavage of sucrose (SCHEME1 ). The main advantage of sucrose synthase over pyrophosphorylases is the utilization of nucleoside diphosphates (NDP) instead of nucleoside triphosphates to generate activated sugars. [less ▲]

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See detailApplication of sucrose synthase in the synthesis of nucleotide sugars and saccharides
Zervosen, Astrid ULg; Elling, Lothar

in Bucke, Christopher (Ed.) Carbohydrate Biotechnology Protocols (1999)

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See detailApplication of Supercritical Carbon Dioxide for the Preparation of a Piroxicam-Beta-Cyclodextrin Inclusion Compound
Van Hees, Thierry ULg; Piel, Géraldine ULg; Evrard, Brigitte ULg et al

in Pharmaceutical Research (1999), 16(12), 1864-70

PURPOSE: Piroxicam is a poorly soluble NSAID, whose solubility is enhanced when included into beta-cyclodextrin. The preparation of a piroxicam-beta-cyclodextrin inclusion compound using supercritical CO2 ... [more ▼]

PURPOSE: Piroxicam is a poorly soluble NSAID, whose solubility is enhanced when included into beta-cyclodextrin. The preparation of a piroxicam-beta-cyclodextrin inclusion compound using supercritical CO2 was investigated. METHODS: The solubility and the stability of piroxicam in supercritical CO2 were determined. Then, the influence of the temperature, the pressure and the time of exposure on the inclusion rate was studied. RESULTS: The solubility of piroxicam varied over a wide range depending on the temperature and pressure (from 0.006 to 1.500 mg/g of CO2). The temperature and the time of exposure had a great influence on the inclusion yield, while pressure did not and a complete inclusion was achieved by keeping a physical mixture of piroxicam and beta-cyclodextrin (1:2.5 mol/mol) for 6 hours at 150 degrees C and 15 MPa of CO2. This complex was characterized by Differential Scanning Calorimetry, differential solubility and Fourier Transform Infrared Spectrometry. CONCLUSIONS: Supercritical carbon dioxide may prove to be a novel useful complexation method of drugs into beta-cyclodextrin. [less ▲]

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See detailApplication of Supercritical carbon dioxide for the preparation of drug-cyclodextrin inclusion compounds
Van Hees, Thierry ULg; Barillaro, Valery; Piel, Géraldine ULg et al

in Journal of Inclusion Phenomena and Macrocyclic Chemistry (2002), 44(1-4), 271-274

Inclusion complexes of drugs into cyclodextrins (CDs) can be obtained at the solid state by means of supercritical dioxide (SCCO2). A successful inclusion with a yield >98.5% has been achieved with ... [more ▼]

Inclusion complexes of drugs into cyclodextrins (CDs) can be obtained at the solid state by means of supercritical dioxide (SCCO2). A successful inclusion with a yield >98.5% has been achieved with piroxicam and beta-CD. The temperature and the time of exposure to SCCO2 have a significant effect on the inclusion yield while the pressure has a negative effect. However, there is a strong interaction between temperature and pressure and this interaction has a positive influence. The molar ratio piroxicam-beta-CD and the addition of ternary alkaline agents were also found to be significant factors. The dissolution rate of the complexes formed using SCCO2 was found to be significantly higher than that of the physical mixture. Inclusion complexes have also been obtained with miconazole treating mixtures of miconazole, CDs and citric acid by SCCO2. This new technique of inclusion of poorly soluble drugs into CDs allows the preparation of solid complexes without using organic solvents and thus without residues. [less ▲]

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See detailThe Application of the 1968 Brussels Convention on Jurisdiction and Judgments : Report for Belgium
Wautelet, Patrick ULg

in Kaye, Peter (Ed.) European Case Law on the Judgments Convention (1998)

In this report, authored together with Prof. Marta Pertegás Sender, we attempt to present an overview of the case law of Belgian courts dealing with the 1968 Brussels Convention (now replaced by the 44 ... [more ▼]

In this report, authored together with Prof. Marta Pertegás Sender, we attempt to present an overview of the case law of Belgian courts dealing with the 1968 Brussels Convention (now replaced by the 44/2001 Regulation). After a brief overview of the legal and court system in Belgium, we review the main provisions of the Convention, explaining for each provision which relevant cases have been decided by courts in Belgium. Cases are summarized and where necessary criticized, mainly in the light of the case law of the European Court of Justice dealing with the 1968 Brussels Convention. [less ▲]

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See detailApplication of the accelerated shelf life testing method (ASLT) to study the survival rates of freeze-dried Lactococcus starter cultures
Achour, M.; Mtimet, N.; Cornelius, C. et al

in Journal of Chemical Technology & Biotechnology (2001), 74

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See detailApplication of the Arbitrary Lagrangian Eulerian Formalism to Stationary Roll Forming Simulations
Boman, Romain ULg; Ponthot, Jean-Philippe ULg

in Advanced Materials Research (2011), 189-193

Due to the length of the mill, accurate modelling of stationary solution of continuous cold roll forming by the finite element method using the classical Lagrangian formulation usually requires a very ... [more ▼]

Due to the length of the mill, accurate modelling of stationary solution of continuous cold roll forming by the finite element method using the classical Lagrangian formulation usually requires a very large mesh leading to huge CPU times. In order to model industrial forming lines including many tools in a reasonable time, the sheet has to be shortened or the element size has to be increased leading to inaccurate results. On top of this, applying loads and boundary conditions on this smaller sheet is usually more difficult than in the continuous case. Moreover, transient dynamic vibrations, which are unnecessarily computed, may appear when the sheet hits each tool, decreasing the convergence rate of the numerical simulation. Beside this classical Lagrangian approach, an alternative method is given by the Arbitrary Lagrangian Eulerian (ALE) formalism which consists in decoupling the motion of the material and the mesh. Starting from an initial guess of the sheet geometry between the rolls, the numerical simulation is performed until the stationary state is reached with a mesh, the nodes of which are fixed in the rolling direction but are free to move on perpendicular plane, following the geometrical boundary of the sheet. The whole forming line can then be modelled using a limited number of brick and contact elements because the mesh is only refined near the tools where bending and contact occur. In this paper, ALE results are compared to previous Lagrangian simulations and experimental measurement on a U-channel, including springback. [less ▲]

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See detailApplication of the Arbitrary Lagrangian Eulerian Formulation to the Numerical Simulation of Cold Roll Forming Process
Boman, Romain ULg; Papeleux, Luc ULg; Bui, Quoc Viet et al

in Journal of Materials Processing Technology (2006), 177(1-3), 621-625

In this paper, the Arbitrary Lagrangian Eulerian formalism is used to compute the steady state of a 3D U-shaped cold roll forming process. Compared to the Lagrangian case, this method allows to keep a ... [more ▼]

In this paper, the Arbitrary Lagrangian Eulerian formalism is used to compute the steady state of a 3D U-shaped cold roll forming process. Compared to the Lagrangian case, this method allows to keep a refined mesh near the tools, thus allowing accurate contact prediction all along the computation with a limited number of elements. Mesh can also be kept refined in the bending zone, thus leading to accurate representation of the sheet with a limited computational time. The main problem of this kind of simulation lies in the rezoning of the nodes on the free surfaces of the sheet. A modified iterative isoparametric smoother is used to manage this geometrically complex and CPU expensive task. (c) 2006 Elsevier B.V. All rights reserved. [less ▲]

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See detailApplication of the Arbitrary Lagrangian Eulerian Formulation to the Numerical Simulation of Forming Process
Boman, Romain ULg; Papeleux, Luc ULg; Ponthot, Jean-Philippe ULg

in Owen, D. R. J.; Oñate, E. (Eds.) COMPLAS 2007 : IX International Conference on Computational Plasticity Fundamentals and Applications (2007, September)

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See detailApplication of the Arbitrary Lagrangian Eulerian Formulation to the Numerical Simulation of Forming Process
Boman, Romain ULg; Papeleux, Luc ULg; Ponthot, Jean-Philippe ULg

in Hora, Pavel (Ed.) Numisheet 2008: 7th International Conference and Workshop on Numerical Simulation of 3D Sheet Metal Forming Processes (2008, September)

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See detailApplication of the CALUX bioassay for epidemiological study: analyses of Belgian human plasma
Van Wouwe, Nathalie; Debacker, Noemi; Sasse, André et al

in Organohalogen Compounds (2004)

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See detailApplication of the characteristic function to evaluate and compare analytical variability in an external quality assessment scheme for serum ethanol
Coucke, Wim; Charlier, Corinne ULg; Lambert, Willy et al

in Clinical Chemistry (2015), 61

As a cornerstone of quality management in the laboratory, External Quality Assessment (EQA) schemes are used to assess laboratory and analytical method performance. The characteristic function is used to ... [more ▼]

As a cornerstone of quality management in the laboratory, External Quality Assessment (EQA) schemes are used to assess laboratory and analytical method performance. The characteristic function is used to describe the relation between the target concentration and the EQA standard deviation, which is an essential part of the evaluation process. The characteristic function is also used to compare the variability of different analytical methods. We fitted the characteristic function to data from the Belgian External Quality Assessment program for serum ethanol. Data included results from headspace gas chromatography and the enzymatic methods of Abbott, Roche, Siemens, and Ortho-Clinical Diagnostics. We estimated the characteristic function with weighted nonlinear regression. By introducing dummy variables, we rewrote the original formula of the characteristic function to assess statistical inference for comparing the variability of the different analytical methods. The characteristic function fitted the data precisely. Comparison between methods showed that there was little difference between the estimated variability for low concentrations, and that the increase in SD with increasing target concentration was slower for Abbott and Roche than for the other methods. The characteristic function can successfully be introduced in clinical schemes, although its applicability to fit the data should always be assessed. Because of its easy parameterization, it can be used to assess differences in performance between analytical methods and to assess laboratory performance. The characteristic function also offers an alternative framework for coefficients of variation to describe variability of analytical methods. [less ▲]

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