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See detailPrediction of selectivity for enantiomeric separations of uncharged compounds by capillary electrophoresis involving dual cyclodextrin systems
Abushoffa, Adel M.; Fillet, Marianne ULg; Hubert, Philippe ULg et al

in Journal of Chromatography. A (2002), 948(1-2), 321-9

The single-isomer polyanionic cyclodextrin (CD) derivative heptakis-6-sulfato-beta-cyclodextrin (HSbetaCD) has been tested as chiral additive for the enantioseparation of non-steroidal anti-inflammatory ... [more ▼]

The single-isomer polyanionic cyclodextrin (CD) derivative heptakis-6-sulfato-beta-cyclodextrin (HSbetaCD) has been tested as chiral additive for the enantioseparation of non-steroidal anti-inflammatory drugs, such as fenoprofen, flurbiprofen, ibuprofen and ketoprofen, in capillary electrophoresis, using a pH 2.5 phosphoric acid-triethanolamine buffer in the reversed polarity mode. In most cases, the enantiomers of these acidic compounds, present in uncharged form at that pH, were only poorly resolved with HSbetaCD alone. However, the use of HSbetaCD in combination with the neutral CD derivative, heptakis-(2,3,6-tri-O-methyl)-beta-cyclodextrin (TMbetaCD), which has a particularly high enantioselectivity towards these compounds, has led to complete enantioresolution in reasonably low migration times in most cases. Affinity constants for the enantiomers with the two cyclodextrins were determined, using linear regression in a two-step approach. Affinity constants with the charged HSbetaCD were first calculated in single systems while those with the neutral TMbetaCD were determined in dual systems. Selectivity for the enantiomeric separation of these compounds in dual CD systems could be predicted using recently developed mathematical models. [less ▲]

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See detailPrediction of signal peptide functional properties: a study of the orientation and angle of insertion of yeast invertase mutants and human apolipoprotein B signal peptide variants.
Talmud, P.; Lins, Laurence ULg; Brasseur, Robert ULg

in Protein Engineering (1996), 9(4), 317-21

A number of studies have introduced mutations into the yeast invertase signal peptide, using it as a model system to elucidate features for targeting, translocation and intracellular transport. Using ... [more ▼]

A number of studies have introduced mutations into the yeast invertase signal peptide, using it as a model system to elucidate features for targeting, translocation and intracellular transport. Using molecular modelling of the invertase signal peptide we have analysed the hydrophobicity potential and the change in dielectric constant of the energy transfer, when the molecule moves from a hydrophobic to a hydrophilic phase at the simulated hydrophobic-hydrophilic interface. This modelling has been carried out on wild type and mutant invertase signal peptides of altered function, previously reported in the literature. While the predicted angle of insertion correlates with the measured extent of invertase secretion, with an optimum angle of 45 degrees, mutations that change the angle of orientation reduce the extent of invertase secretion. We have applied these same molecular modelling principles to the naturally occurring variants of the human apolipo-protein B (apoB) signal peptide, that confer a secretion defective phenotype when fused to yeast invertase and expressed in yeast. Our modelling thus identifies a strong correlation between the predicted angle of insertion of the signal peptide into the membrane and its ability to direct secretion. [less ▲]

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See detailPrediction of Stiction in Microswitch Systems
Wu, Ling ULg; Rochus, Véronique ULg; Noels, Ludovic ULg et al

in EUROSIME 2010 (2010)

Stiction is a major failure mode of MEMS as microscopic structures tend to adhere to each other when their surfaces enter into contact. Although increasing the restoring forces of switch devices could ... [more ▼]

Stiction is a major failure mode of MEMS as microscopic structures tend to adhere to each other when their surfaces enter into contact. Although increasing the restoring forces of switch devices could overcome the stiction effect, this is not practical, as in turn, it also increases the actuation voltage. Therefore stiction prediction is important to be considered when designing micro- and nano- devices. In this paper, the numerical prediction of stiction for capacitive MEMS switches is considered. Toward this end, a micro-adhesive-contact law is derived from previous work and combined with a finite-element model. [less ▲]

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See detailPrediction of stillbirth by monotoring endocrine and metabolic parameters in dairy cattle
Szenci, 0; Bajcsy, A. C.; Brydl, E. et al

in Reproduction in Domestic Animals (2010), 45(Suppl 3), 109

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See detailPrediction of stillbirth in Holstein-Friesian dairy cows by monotoring endocrine profiles in the periparturient period.
Szenci, O.; Bajcsy, A.Cs; Nagy, K. et al

in Proceedings of the 6th European Congress of Bovine Health and Management (ECBHM) (2011, September 07)

During the last decades, there is a declining trend in conception and calving rates in high yielding Holstein dairy cattle. At the same time, the gradual increase in stillbirth rates, especially in ... [more ▼]

During the last decades, there is a declining trend in conception and calving rates in high yielding Holstein dairy cattle. At the same time, the gradual increase in stillbirth rates, especially in Holstein heifers, has until recently received relatively little attention. Birth weight and gender of the calf, parity, age and breed of the dam, and season of calving are all factors associated with calving difficulties and stillbirths. Other causes of stillbirths not related to calving difficulties are, for example, herd size, infections (e.g. BVD), insufficient placenta development and/or function, metabolic disorders of the cow, and congenital malformations of the calf. The objective of the present study was to investigate the possible effect of hormonal disturbances on the incidence of stillbirth in dairy cows on a Holstein-Friesian dairy farm in Hungary. Dairy cows (n=173) were sampled three times during the periparturient period (at drying-off, 3 weeks prior to expected calving, and within 1 h after calving) in 2006 and two times (3 weeks prior to expected calving, and within 1 h after calving) in 2007. Dairy cows were grouped according to the incidence of stillbirth: Group 1 (control): n=165 and Group 2 (stillbirth): n=8. Hormone and pregnancy protein parameters measured by RIA were as follows: progesterone (P4), estradiol (E2), cortisol, triiodine-thyronin (T3), thyroxin (T4), insulin, insulin-like growth factor (IGF-1) and pregnancy associated glycoprotein (PAG). To determine, which of the hormones and PAG were the best predictors of the presence or absence of stillbirth at a given time (2 months and 3 weeks before calving and within 1 h after calving), a generalised linear model was used with binomial error distribution and logit link function (multivariate logistic regression). All analyses were carried out by R 2.7.2. Statistical Software. The significant level was set at P< 0.05 and an effect was considered a trend when P was between 0.05 and 0.10. The overall prevalence of stillbirth was 4.6 % (4.0% in 2006 and 5.4% in 2007). Interestingly, most calves (7 out of 8) with stillbirth were bulls, but this difference was not significant. Weight of the calves, body score condition of the cows and number of people needed to assist at calving also did not affect the presence or absence of stillbirth significantly, and there was no significant difference among the groups regarding the gestation length or parity either (P>0.100 in all cases). Regarding hormone and pregnancy protein parameters, no significant differences were found during the periparturient period (at 2 months and 3 weeks before expecting calving), however, there was a trend for lower IGF-1 values (P=0.079, OR=0.96) in stillbirth group compared to controls at dry off (2 months before expecting calving). Within one hour after calving significant differences were observed in case of P4 (P<0.001, OR= 3.06), and IGF-1 (P=0.021, OR= 0.94), resulting significantly higher values in P4 and lower values in IGF-1 in stillbirth cows compared to controls. The higher P4 values observed in stillbirth cows also resulted a higher P4/E2 ratio compared to controls (P=0.003, OR= 1.60). Changes in the IGF-1, P4 and P4/E2 ratio may be one of the reasons for stillbirth in Holstein-Friesian dairy cows however more examinations are needed to be confirmed. Other hormones (P4, cortisol, T3, T4, insulin, PAG) did not mirror dependency due to the incidence of stillbirth in dairy cows. [less ▲]

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See detailPrediction of strain for intermittent heat exposures
Mairiaux, Philippe ULg; Libert, J. P.; Candas, V. et al

in Ergonomics (1986), 29(7), 913-23

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See detailPrediction of technological and organoleptic properties of beef Longissimus thoracis from near-infrared reflectance and transmission spectra
Leroy, Bernadette ULg; Lambotte, S.; Dotreppe, Olivier ULg et al

in Meat Science (2003), 66(1), 45-54

Technological and organoleptic properties of beef cuts were predicted by near-infrared (NIR) spectroscopy. Spectra were collected on 189 beef Longissimus thoracis muscle samples using, transmission (NIRT ... [more ▼]

Technological and organoleptic properties of beef cuts were predicted by near-infrared (NIR) spectroscopy. Spectra were collected on 189 beef Longissimus thoracis muscle samples using, transmission (NIRT) and reflectance with a probe. Quality assessment and NIR recordings were performed on sliced loin after 2 and 8 days ageing. Partial least squares regression yielded determination coefficients of cross-validation (R-cv(2)) of 0.12-0.25 for the prediction of Warner-Bratzler Peak Shear Force in reflectance and 0.15-0.41 in transmission. Higher R-cv(2) were obtained for L* parameter (0.83-0.85), a* (0.39-0.49) and b* (0.73-0.75) with reflectance. Predictions of drip loss and cooking loss were less accurate with a R-cv(2) range of 0.38 to 0.54 and 0.25 to 0.47, respectively. The NIR spectra collected on fresh meat show good potential to predict CIE L* and b* parameters in reflectance mode. (C) 2003 Elsevier Ltd. All rights reserved. [less ▲]

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See detailPrediction of technological and organoleptic properties of porcine meat by near infrared spectroscopy
Meulemans, Alexandra; Dotreppe, Olivier ULg; Leroy, Bernadette ULg et al

in Proceedings of the 48th International Congress of Meat Science and Technology (2002)

The aim of the present study was to evaluate the Fourier Transform NIR spectroscopy as a potential technique for prediction of technological (pH and WHC) and organoleptic (color and tenderness) properties ... [more ▼]

The aim of the present study was to evaluate the Fourier Transform NIR spectroscopy as a potential technique for prediction of technological (pH and WHC) and organoleptic (color and tenderness) properties of porcine meat. From this study, it can be concluded that NIR spectroscopy shows good potentiality for prediction of several color and water holding capacity parameters. The quality of the models could be improved by using a larger number of samples or, alternatively, by choosing samples with larger variability, or possibly by performing reference analysis and NIR analysis on the same day. Since the spectra were obtained on minced meat, these results have to be confirmed when applying the technique on intact meat in the laboratory or on the slaughterline. [less ▲]

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See detailPrediction of the acoustics of coupled rooms with the acoustic-diffusion model
Valeau, Vincent; Billon, Alexis ULg; Hodgson, Murray et al

Conference (2006, June)

A general model is proposed to simulate the acoustics of coupled rooms. It is based on a diffusion equation, solved numerically to perform acoustic predictions. The presence of scattering objects –or the ... [more ▼]

A general model is proposed to simulate the acoustics of coupled rooms. It is based on a diffusion equation, solved numerically to perform acoustic predictions. The presence of scattering objects –or the “fittings”– is also taken into account. Distinct sub-volumes can be defined, representing either coupled volumes or zones with different fitting characteristics. Some sample results are presented, and compared with ray-tracing results and experimental data. Two situations are assessed: two coupled classrooms, and a room divided into two zones, one empty, one fitted. The diffusion-model predictions match the other data satisfactorily, both in terms of sound attenuation and sound decay. Diffusion-based results are obtained with the advantage of low computational time compared to ray-tracing results. [less ▲]

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See detailPrediction Of The Antigenic Sites Of The Cystic-Fibrosis Transmembrane Conductance Regulator Protein By Molecular Modeling
Gallet, X.; Benhabiles, N.; Lewin, M. et al

in Protein Engineering (1995), 8(8), 829-34

Antibodies are powerful tools for studying the in situ localization and physiology of proteins. The prediction of epitopes by molecular modelling has been used successfully for the papilloma virus, and ... [more ▼]

Antibodies are powerful tools for studying the in situ localization and physiology of proteins. The prediction of epitopes by molecular modelling has been used successfully for the papilloma virus, and valuable antibodies have been raised [Muller et al. (1990) J. Gen. Virol., 71, 2709-2717]. We have improved the modelling approach to allow us to predict epitopes from the primary sequences of the cystic fibrosis transmembrane conductance regulator. The procedure involves searching for fragments of primary sequences likely to make amphipathic secondary structures, which are hydrophilic enough to be at the surface of the folded protein and thus accessible to antibodies. Amphipathic helices were predicted using the methods of Berzofsky, Eisenberg and Jahnig. Their hydrophobic-hydrophilic interface was calculated and drawn, and used to predict the orientation of the helices at the surface of the native protein. Amino acids involved in turns were selected using the algorithm of Eisenberg. Tertiary structures were calculated using 'FOLDING', a software developed by R. Brasseur for the prediction of small protein structures [Brasseur (1995) J. Mol. Graphics, in press]. We selected sequences that folded as turns with at least five protruding polar residues. One important property of antibodies is selectivity. To optimize the selectivity of the raised antibodies, each sequence was screened for similarity (FASTA) to the protein sequence from several databanks. Ubiquitous sequences were discarded. This approach led to the identification of 13 potential epitopes in the cystic fibrosis transmembrane conductance regulator: seven helices and six loops. [less ▲]

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See detailPrediction of the cross-section capacity of hot-rolled profiles using the direct strength method and the continuous strength method
Li, Yongzhen ULg; Rossi, Barbara ULg

in Chan, S.L.; Shu, G.P. (Eds.) Proceedings of seventh International Conference on Advances in Steel Structures (2012, April)

Material yielding on one hand and local buckling on the other hand limit the cross-section capacity of steel structural members. Current structural design codes use the concept of cross-section ... [more ▼]

Material yielding on one hand and local buckling on the other hand limit the cross-section capacity of steel structural members. Current structural design codes use the concept of cross-section classification to determine the cross-section resistance of hot-rolled profiles. In this system, the Effective Width Method (EWM) is employed to account for local buckling effects for slender, class 4, cross-sections. Alternative design methods for treatment of local buckling in metallic cross-sections have been proposed, including the Direct Strength Method (DSM), developed for cold-formed steel structural profiles, and, recently, the Continuous Strength Method (CSM). The DSM is based on the assumption that the strength can be predicted from the ratio of the yield strength to the elastic critical load in conjunction with a strength curve for the entire cross-section. Thus it is essentially an extension of the use of column curves for global buckling, but with application to local buckling instability. The CSM is a deformation-based design approach which is based on a continuous relationship between cross-sectional slenderness and cross-section deformation capacity and a rational exploitation of strain hardening. This paper is focused on the evaluation of the cross-sectional resistance of hot-rolled structural profiles. Test data from literature experimental programmes have been gathered and analysed to compare the predictions from the DSM and CSM design approaches. [less ▲]

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See detailPrediction of the morphological and mechanical properties of a novel scaffold ACL tissue engineering
Laurent, Cédric ULg

in Computer Methods in Biomechanics & Biomedical Engineering (2011)

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See detailPrediction of the reverberation time in rooms with non uniform absorptions using a diffusion model
Billon, Alexis ULg; Sakout, Anas

Conference (2006, July)

The acoustical comfort is now a comfort’s criterion which is taken into from the conception. The designers need therefore accurate tools to predict the acoustic quality of enclosures. Most of the ... [more ▼]

The acoustical comfort is now a comfort’s criterion which is taken into from the conception. The designers need therefore accurate tools to predict the acoustic quality of enclosures. Most of the acoustical comfort criteria are based on the reverberation time. When the room has proportionate dimensions and an uniform absorption, the statistical theory through Sabine or Eyring formulas allows good predictions of the reverberation time. Moreover, extensions of these relations by Millington or Cremer and Müller among others give quite satisfactory when the room is composed of materials with different sound absorption. In this study, the reverberation time in an enclosure is calculated via the numerical resolution of unstationary diffusion equation, model validated in coupled and industrial rooms. Firstly, an improvement of the boundary condition is proposed for highly absorbent surfaces. The diffusion model is then compared to several formulations of the statistical theory and a ray-tracing software for a cubic room with homogeneous walls’ absorption and with non homogeneous walls’ absorptions. Finally, an experimental validation is conducted for an enclosure with non uniformly distributed absorption. [less ▲]

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See detailPrediction of the Semi-Rigid and Partial-Strength Properties of Structural Joints
Jaspart, Jean-Pierre ULg; Maquoi, René ULg

in Proceedings of the SSRC Annual technical Session and Meeting (1994, June)

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See detailPrediction of the sound pressure levels using a diffusion model: numerical validations and experimental comparisons
Billon, Alexis ULg; Picaut, Judicaël

in Journal of the Acoustical Society of America (2008), 123(5), 3924-3924

redictions of sound propagation in urban areas have attracted a considerable over the years. If the sound energy is assimilated to particles with a constant energy, their movement can be described by a ... [more ▼]

redictions of sound propagation in urban areas have attracted a considerable over the years. If the sound energy is assimilated to particles with a constant energy, their movement can be described by a transport equation. In canyon streets, this transport equation can be reduced to a diffusion equation whose expression is more simple. In this presentation, sound absorption at the boundaries (buildings facades and ground), as well as atmospheric sound attenuation are introduced. The problem is then solved numerically using a finite elements method for the configuration of a canyon street. A systematic validation of the obtained model is carried out in terms of sound pressure level by comparison to numerical simulations taken from the literature. Comparisons with experimental data are then conducted. Finally, applications in more complex configurations are presented. [less ▲]

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See detailPrediction of the Tension/Compression asymmetry of ECAP processed FCC material using an integrated model based on dislocation and back-stress
Chen, Enze; Duchene, Laurent ULg; Habraken, Anne ULg et al

in Materials Science Forum (2011), 667-669

In our recent work, a new integrated model was proposed to describe the back-stress evolution based on the dislocation substructure and texture. By relating the back-stress to the dislocation density in ... [more ▼]

In our recent work, a new integrated model was proposed to describe the back-stress evolution based on the dislocation substructure and texture. By relating the back-stress to the dislocation density in cell walls and in the cell interior, this model is able to capture the back-stress evolution of ECAP processed pure aluminium. In this paper, the model is used for another FCC material, namely copper. The aim is to check whether this model is able to predict the tension/compression asymmetry (due to the back-stress) of copper. The results show that this is indeed the case and it is also found that the strain rate ratio proposed in our previous work [1] is a function of the dislocation density ratio. [less ▲]

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See detailPrédiction structurée multitâche itérative de propriétés structurelles de protéines
Maes, Francis ULg; Becker, Julien ULg; Wehenkel, Louis ULg

in 7e Plateforme AFIA: Association Française pour l'Intelligence Artificielle (2011)

Le développement d'outils informatiques pour prédire de l'information structurelle de protéines à partir de la séquence en acides aminés constitue un des défis majeurs de la bioinformatique. Les problèmes ... [more ▼]

Le développement d'outils informatiques pour prédire de l'information structurelle de protéines à partir de la séquence en acides aminés constitue un des défis majeurs de la bioinformatique. Les problèmes tels que la prédiction de la structure secondaire, de l'accessibilité au solvant, ou encore la prédiction des régions désordonnées, peuvent être exprimés comme des problèmes de prédiction avec sorties structurées et sont traditionnellement résolus individuellement par des méthodes d'apprentissage automatique existantes. Etant donné que ces problèmes sont fortement liés les uns aux autres, nous proposons de les traiter ensemble par une approche d'apprentissage multitâche. A cette fin, nous introduisons un nouveau cadre d'apprentissage générique pour la prédiction structurée multitâche. Nous appliquons cette stratégie pour résoudre un ensemble de cinq tâches de prédiction de propriétés structurelles des protéines. Nos résultats expérimentaux sur deux jeux de données montrent que la stratégie proposée est significativement meilleure que les approches traitant individuellement les tâches. [less ▲]

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