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See detailA new statistical method for the automated detection of peaks in UV-DAD chromatograms of a sample mixture
Debrus, Benjamin ULg; Lebrun, Pierre ULg; Ceccato, Attilio ULg et al

in Talanta (2009), 79

One of the major issues within the context of the fully automated development of chromatographic methods consists of the automated detection and identification of peaks coming from complex samples such as ... [more ▼]

One of the major issues within the context of the fully automated development of chromatographic methods consists of the automated detection and identification of peaks coming from complex samples such as multi-component pharmaceutical formulations or stability studies of these formulations. The same problem can also occur with plant materials or biological matrices. This step is thus critical and time-consuming, especially when a Design of Experiments (DOE) approach is used to generate chromatograms. The use of DOE will often maximize the changes of the analytical conditions in order to explore an experimental domain. Unfortunately, this generally provides very different and “unpredictable” chromatograms which can be difficult to interpret, thus complicating peak detection and peak tracking (i.e. matching peaks among all the chromatograms). In this context, Independent Components Analysis (ICA), a new statistically based signal processing methods was investigated to solve this problem. The ICA principle assumes that the observed signal is the resultant of several phenomena (known as sources) and that all these sources are statistically independent. Under those assumptions, ICA is able to recover the sources which will have a high probability of representing the constitutive components of a chromatogram. In the present study, ICA was successfully applied for the first time to HPLC–UVDAD chromatograms and it was shown that ICA allows differentiation of noise and artifact components from those of interest by applying clustering methods based on high-order statistics computed on these components. Furthermore, on the basis of the described numerical strategy, itwas also possible to reconstruct a cleaned chromatogram with minimum influence of noise and baseline artifacts. This can present a significant advance towards the objective of providing helpful tools for the automated development of liquid chromatography (LC) methods. It seems that analytical investigations could be shortened when using this type of methodologies. [less ▲]

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See detailNew strategies and new impact of cancer imaging
Couturier, Olivier; Hustinx, Roland ULg; Chatal, Jean-François

in SERVIER, Jacques (Ed.) Cancer : recent evidence, innovative strategies, future promises (2004)

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See detailNew strategies to prepare melt processable polymer-grafted gold nanoparticles
Alexandre, Michaël ULg; Abetz, Volker; Boschetti-de-Fierro, A. et al

Poster (2008, November 28)

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See detailNew strategy for comprehensive analysis of polybrominated diphenyl ethers, polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and polychlorinated biphenyls by gas chromatography coupled with mass spectrometry
Pirard, Catherine; De Pauw, Edwin ULg; Focant, Jean-François ULg

in Journal of Chromatography. A (2003), 998(1-2), 169-181

A strategy for determination of polybrominated diphenyl ethers, polychlorinated dibenzodioxins, polychlorinated dibenzofurans and polychlorinated biphenyls on fatty matrices has been established. After ... [more ▼]

A strategy for determination of polybrominated diphenyl ethers, polychlorinated dibenzodioxins, polychlorinated dibenzofurans and polychlorinated biphenyls on fatty matrices has been established. After extraction, the proposed method allows the purification and the fractionation of all target groups of compounds in a simple multi-step automated clean-up. Furthermore, their subsequent analysis is carried out using a single benchtop mass spectrometer, in four separate injections. Required sensitivity considering levels found in the environment is attained using electron impact ionisation followed by tandem in time mass spectrometry. The whole method has been evaluated on standard solution and quality control samples consisting of fortified beef fat. Sensitivity, selectivity, accuracy and repeatability were tested with satisfactory results. (C) 2003 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailNew Strategy for the Preparation of Clickable Peptides and Labeling with 1-(Azidomethyl)-4-[18F]-fluorobenzene for PET
Thonon, David ULg; Paris, Jérôme ULg; Kech, Cecile et al

in Bioconjugate Chemistry (2009), 20(4), 817-823

The alkyne-azide Cu(I)-catalyzed Huisgen cycloaddition, a click type reaction was used to label a peptide with fluorine-18. A novel solid phase synthesis approach for the preparation of clickable peptides ... [more ▼]

The alkyne-azide Cu(I)-catalyzed Huisgen cycloaddition, a click type reaction was used to label a peptide with fluorine-18. A novel solid phase synthesis approach for the preparation of clickable peptides has been developed and has also permitted the straightforward preparation of reference compounds. A complementary azide labeling agent (1-(azidomethyl)-4-[18F]-fluorobenzene) has been produced in a four step procedure in 75 min with a 34% radiochemical yield (decay corrected). Conjugation of [18F]fluoroazide with a model alkyne-neuropeptide produced the desired 18F-radiolabeled peptide in less than 15 min with a yield of 90% and excellent radiochemical purity [less ▲]

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See detailNew strategy for the validation of chromatographic bioanalytical methods
Chapuzet, E.; Mercier, N.; Bervoas-Martin, S. et al

in STP Pharma Pratiques (2000), 10(1), 21-38

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See detailA new strategy to improve the bovine resistance to respiratory disease or when respiratory physiology meets beef selection
Bureau, Fabrice ULg; Lekeux, Pierre ULg

in Wensing, Th (Ed.) Production Diseases in Farm Animals (1999)

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See detailNew strategy to in vitro evaluation of antimalarial drugs demonstre advantage of Artemisia annua crude extract on antimalarial effect by its tools to cross intestinal barrier
Melilo de Magalhaes, Pedro; Schneider, Y. J.; Dupont, Isabelle et al

Poster (2010, October 03)

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See detailNew strictosidine beta-glucosidase from Strychnos mellodora
Brandt, Viviane; Geerlings, Arjan; Tits, Monique ULg et al

in Plant Physiology & Biochemistry (2000), 38(3), 187-192

A stable strictosidine glucosidase was isolated from dried powdered material of Strychnos mellodora. The kinetic parameters Km and Vmax of the purified glucosidases from catharanthus roseus and S ... [more ▼]

A stable strictosidine glucosidase was isolated from dried powdered material of Strychnos mellodora. The kinetic parameters Km and Vmax of the purified glucosidases from catharanthus roseus and S. mellodora towards strictosidine, dolichantoside and palicoside were determined and compared. [less ▲]

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See detailNew Studies and Progress in Ne IV, V and VI Term Analysis
Bastin, Thierry ULg; Biémont, Emile ULg; Dumont, Paul-Dominique ULg et al

in Proceedings of the 5th International Colloquium on Atomic Spectra and Oscillator Strengths for Astrophysical and Laboratory Plasmas (1996)

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See detailA new subspace-based approach to identify nonlinear mechanical structures in the frequency domain
Noël, Jean-Philippe ULg; Kerschen, Gaëtan ULg

in Proceedings of the 16th IFAC Symposium on System Identification (2012, July)

This paper introduces a new frequency-domain subspace-based method for the identification of nonlinear mechanical systems. The technique exploits frequency data and interprets nonlinearities as feedback ... [more ▼]

This paper introduces a new frequency-domain subspace-based method for the identification of nonlinear mechanical systems. The technique exploits frequency data and interprets nonlinearities as feedback forces exciting the underlying linear system. It is demonstrated using two academic examples, a Duffing oscillator and a five degree-of-freedom system comprising two nonlinearities. [less ▲]

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See detailNew substituted aryl esters and aryl amides of 3,4-dihydro-2H-1,2,4- benzothiadiazine 1,1-dioxides as positive allosteric modulators of AMPA receptors
Dintilhac, Gaëlle ULg; Arslan, Deniz ULg; Dilly, Sébastien ULg et al

in MedChemComm (2011), 2

AMPA receptor potentiators belonging to 3,4-dihydro-2H-1,2,4-benzothiadiazine 1,1-dioxides have been found to be of great interest as cognitive enhancers. Previous structure–activity relationships have ... [more ▼]

AMPA receptor potentiators belonging to 3,4-dihydro-2H-1,2,4-benzothiadiazine 1,1-dioxides have been found to be of great interest as cognitive enhancers. Previous structure–activity relationships have demonstrated the importance for activity of the nature of the substituent at the 7-position of the heterocycle. This work aims to explore the impact on AMPA potentiation of the introduction of different aryl and aralkyl ester or aryl amide groups at the 7-position. The new synthesized compounds were evaluated as AMPA receptor potentiators by examining their effect on rat brain primary cell cultures on AMPA-evoked membrane depolarisation using fluorescent membrane potential dyes and on imaging-based plate reader. The most potent compound of this series was 2-methylphenyl 4-methyl- 3,4-dihydro-2H-1,2,4-benzothiadiazine-7-carboxylate 1,1-dioxide 16c which provoked a strong potentiation of AMPA current with a potency close to that reported for the best reference compounds of the benzothiadiazine class (i.e cyclothiazide). This work also revealed that only the ortho-substitution of the phenyl group of 1,2,4-benzothiadiazine-7-carboxylate esters provided potent AMPA receptor potentiators opening the way to further chemical exploration. [less ▲]

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See detailA new substrate cycle in plants. Evidence for a high glucose-phosphate-to-glucose turnover from in vivo steady-state and pulse-labeling experiments with [13C]glucose and [14C]glucose.
Alonso, Ana Paula; Vigeolas, Hélène ULg; Raymond, Philippe et al

in Plant Physiology (2005), 138(4), 2220-32

Substrate (futile) cycling involving carbohydrate turnover has been widely reported in plant tissues, although its extent, mechanisms, and functions are not well known. In this study, two complementary ... [more ▼]

Substrate (futile) cycling involving carbohydrate turnover has been widely reported in plant tissues, although its extent, mechanisms, and functions are not well known. In this study, two complementary approaches, short and steady-state labeling experiments, were used to analyze glucose metabolism in maize (Zea mays) root tips. Unidirectional rates of synthesis for storage compounds (starch, Suc, and cell wall polysaccharides) were determined by short labeling experiments using [U-14C]glucose and compared with net synthesis fluxes to determine the rate of glucose production from these storage compounds. Steady-state labeling with [1-(13)C]glucose and [U-13C]glucose showed that the redistribution of label between carbon C-1 and C-6 in glucose is close to that in cytosolic hexose-P. These results indicate a high resynthesis flux of glucose from hexose-P that is not accounted for by glucose recycling from storage compounds, thus suggesting the occurrence of a direct glucose-P-to-glucose conversion. An enzyme assay confirmed the presence of substantial glucose-6-phosphatase activity in maize root tips. This new glucose-P-to-glucose cycle was shown to consume around 40% of the ATP generated in the cell, whereas Suc cycling consumes at most 3% to 6% of the ATP produced. The rate of glucose-P cycling differs by a factor of 3 between a maize W22 line and the hybrid maize cv Dea, and is significantly decreased by a carbohydrate starvation pretreatment. [less ▲]

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See detailNew sulfonylurea torasemide derivatives as potential antihypertensive drugs
Masereel, B.; Pirotte, Bernard ULg; Schynts, M. et al

Poster (1990, September)

Detailed reference viewed: 5 (1 ULg)
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See detailNew sulfonylurea torasemide derivatives as potential antihypertensive drugs
Masereel, B.; Pirotte, Bernard ULg; Schynts, M. et al

in Journal de Pharmacie de Belgique (1990), 45

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See detailA new super-element for estimating the collision resistance of an inclined ship side
Buldgen, Loïc ULg; Le Sourne, Hervé; Rigo, Philippe ULg

in Advancements in Marine Structures : Proceedings of MARSTRUCT 2013, the 4th International Conference on Marine Structures, Espoo, Finland, 25th – 27th March 2013 (2013)

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See detailNew Surface-Enhanced Raman Scattering Platforms: Composite Calcium Carbonate Microspheres Coated with Astralen and Silver Nanoparticles
Stetciura, Inna Y.; Markin, Alexey V.; Ponomarev, Andrei N. et al

in Langmuir (2013), 29

Detailed reference viewed: 38 (4 ULg)