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See detailAutomated quantification of creatinine kinase MB isoenzyme in serum by radial partition immunoassay, with use of the Stratus analyzer
Chapelle, Jean-Paul ULg; El Allaf, M.

in Clinical Chemistry (1990), 36(1), 99-101

We evaluated the analytical and clinical performances of a new radial partition immunoassay for measuring the mass concentration of creatine kinase (CK)-MB in serum. All pipetting, washes, incubations and ... [more ▼]

We evaluated the analytical and clinical performances of a new radial partition immunoassay for measuring the mass concentration of creatine kinase (CK)-MB in serum. All pipetting, washes, incubations and data reduction were performed in 8 min by the Stratus (Dade) fluorometric analyzer. Within-assay and between-assay CVs were respectively 5.5% and 8.4% at 21 micrograms/L, and 4.2% and 3.4% at 48 micrograms/L. Assaying serial dilutions of serum samples with high CK-MB concentrations demonstrated excellent linearity. Results of the Stratus technique correlated well (n = 115, r = 0.98) with those of the Tandem-E CKMB II assay. There was no interference from hemolysis, bilirubin, rheumatoid factor, or added CK-MM (up to 3500 U/L); consequently, CK-MB can be determined in undiluted serum, even in the presence of high total CK activity. The mean CK-MB concentration in 105 blood donors was 1.9 (SD 1.3) micrograms/L. For seven myocardial infarction patients who received prompt fibrinolytic therapy, the mean CK-MB concentration was 4.5 (SD 1.8) micrograms/L at admission, and maximum concentrations, 119 (SD 94) micrograms/L, were recorded 16 h later. CK-MB returned to concentrations less than 10 micrograms/L within 72 h. [less ▲]

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See detailAutomated radiosynthesis of [18F]MPPF derivatives for imaging 5-HT1A receptors
Goblet, David ULg; Thonon, David ULg; Plenevaux, Alain ULg et al

Poster (2010, May 30)

TOPIC: Molecular Neuroimaging: from Bench to Bedside Automated radiosynthesis of [18F]MPPF derivatives for imaging 5-HT1A receptors Introduction: Dysfunction of the cerebral serotoninergic system is ... [more ▼]

TOPIC: Molecular Neuroimaging: from Bench to Bedside Automated radiosynthesis of [18F]MPPF derivatives for imaging 5-HT1A receptors Introduction: Dysfunction of the cerebral serotoninergic system is implicated in numerous neurodegenerative disorders such as Alzheimer disease’s, dementia, depression, anxiety, schizophrenia, and Parkinson disease’s. The 5-HT1A serotonin receptors are involved in several physiological functions including sleep, mood, neurogenesis and learning [1]. Consequently, there have been huge efforts in finding ligands for this receptor. [11C]WAY-100635 is a high affinity radioligand used for quantifying serotonin 5-HT1A receptors with positron emission tomography. An 18F-labeled radioligand is advantageous because of higher specific activity and physical/nuclear properties (t1/2= 109 min, 97% of positron decay and positron energy of 635 keV maximum). [18F]MPPF, a selective 5-HT1A antagonist derived from WAY-100635, is currently one of the most successful PET ligand used for 5-HT1A receptor imaging [2]. However the affinity is lower then WAY-100635 and the amount of [18F]MPPF reaching the brain is relatively low since MPPF is a substrate for p-glycoprotein [3]. Methods: In order to improve the brain uptake of the radiotracer, a desmethylated analog has been developed in our lab and preliminary in vitro studies show positive results [4]. Nevertheless, the radiosynthesis take place in two steps as a protecting group removal is needed. A one step procedure with a MPPF derivative could be of very great interest. We have synthesized many MPPF derivatives in our lab (modification on the phenylpiperazine moiety) and developed an automated radiosynthesis procedure for the production of these radiotracers. [18F]MPPF was chosen as the model compound. We used a GE Healthcare FASTlabTM module and made modifications to the [18F]FDG synthesis sequence and cassette. [18F]MPPF was synthesized by coupling of [18F]FBA with the corresponding amine. After coupling, the crude solution was diluted with water and passed through a tC18 cartridge for prepurification. After elution, the [18F]MPPF was purified by semi-preparative HPLC. Results: Total synthesis time, including purification was approximately 100 min. [18F]FBA and [18F]MPPF were obtained at a corrected yield of 55% (n=20) and 25% (n=5) respectively. The radiochemical purity, checked by radio-TLC and UPLC, was >95%. Conclusions: We have developed an automated method for [18F]MPPF and derivatives production using a commercial synthesizer (FASTlabTM from GE Healthcare) and a conventional HPLC system resulting in good yields and high (radio)chemical purity. By simply switching the vial containing the modified amine, an 18F-labeled MPPF derivative could be obtained. Radiosynthesis is still under optimization and the radiotracers synthesized need to be tested as suitable 5-HT1A radioligands. Acknowledgement: This work was supported by the Fondation Rahier. References: [1] Filip M., Bader M. et Al, Pharmacol Rep. 2009 Sep-Oct; 61(5):761-77 [2] Aznavour N, Zimmer L. Et Al, Neuropharmacology. 2007 Mar; 52(3):695-707 [3] Laćan G., Plenevaux A. et Al, Eur J Nucl Med Mol Imaging. 2008 Dec;35(12):2256-66 [4] Defraiteur C., Plenevaux A. et Al., Br J Pharmacol. 2007 Nov; 152(6):952-8 [less ▲]

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See detailAutomated respiratory cycles selection improves the variability of respiratory mechanics monitoring.
Rigo, Vincent ULg; Graas, Estelle; Rigo, Jacques ULg

in Rimensberger, Peter (Ed.) 10th European Conference on Pediatric and Neonatal Ventilation program (2010, April)

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See detailAutomated respiratory cycles selection is highly specific and improves respiratory mechanics analysis.
RIGO, Vincent ULg; Graas, Estelle ULg; Rigo, Jacques ULg

in Pediatric Critical Care Medicine (2012), 13(4), 234-9

OBJECTIVE:: Selected optimal respiratory cycles should allow calculation of respiratory mechanic parameters focusing on patient-ventilator interaction. New computer software automatically selecting ... [more ▼]

OBJECTIVE:: Selected optimal respiratory cycles should allow calculation of respiratory mechanic parameters focusing on patient-ventilator interaction. New computer software automatically selecting optimal breaths and respiratory mechanic derived from those cycles are evaluated. DESIGN:: Retrospective study. SETTING:: University level III neonatal intensive care unit. SUBJECTS:: Ten mins synchronized intermittent mandatory ventilation and assist/control ventilation recordings from ten newborns. INTERVENTION:: The ventilator provided respiratory mechanic data (ventilator respiratory cycles) every 10 secs. Pressure, flow, and volume waves and pressure volume, pressure flow, and ventilator volume flow loops were reconstructed from continuous pressure/volume recordings. Visual assessment determined assisted leak-free optimal respiratory cycles (selected respiratory cycles). New software graded the quality of cycles (automated respiratory cycles). Respiratory mechanic values were derived from both sets of optimal cycles. We evaluated quality selection and compared mean values and their variability according to ventilatory mode and respiratory mechanic provenance. To assess discriminating power, all 45 "t" values obtained from interpatient comparisons were compared for each respiratory mechanic parameter. MEASUREMENTS AND MAIN RESULTS:: A total of 11,724 breaths are evaluated. automated respiratory cycle/selected respiratory cycle selections agreement is high: 88% of maximal kappa with linear weighting. Specificity and positive predictive values are 0.98 and 0.96, respectively. Averaged values are similar between automated respiratory cycle and ventilator respiratory cycle. C20/C alone is markedly decreased in automated respiratory cycle (1.27 +/- 0.37 vs. 1.81 +/- 0.67). Tidal volume apparent similarity disappears in assist/control: automated respiratory cycle tidal volume (4.8 +/- 1.0 mL/kg) is significantly lower than for ventilator respiratory cycle (5.6 +/- 1.8 mL/kg). Coefficients of variation decrease for all automated respiratory cycle parameters in all infants. "t" values from ventilator respiratory cycle data are two to three times higher than ventilator respiratory cycles. CONCLUSIONS:: Automated selection is highly specific. Automated respiratory cycle reflects most the interaction of both ventilator and patient. Improving discriminating power of ventilator monitoring will likely help in assessing disease status and following trends. Averaged parameters derived from automated respiratory cycles are more precise and could be displayed by ventilators to improve real-time fine tuning of ventilator settings. [less ▲]

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See detailAutomated Sample Preparation for Same-Day POP Analysis
Focant, Jean-François ULg

Scientific conference (2011, November)

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See detailAutomated Sample Preparation Techniques for the Determination of Drug Enantiomers in Biological Fluids Using Liquid Chromatography with Chiral Stationary Phases
Ceccato, Attilio ULg; Toussaint, B.; Chiap, Patrice ULg et al

in Enantiomer (1999), 4(3-4), 305-15

The determination of drug enantiomers has become of prime importance in the field of pharmaceutical and biomedical analysis. Liquid chromatography (LC) is one of the most frequently used techniques for ... [more ▼]

The determination of drug enantiomers has become of prime importance in the field of pharmaceutical and biomedical analysis. Liquid chromatography (LC) is one of the most frequently used techniques for achieving the separation and quantitation of the enantiomers of drug compounds. In the bioanalytical field, the integrated systems present an interesting alternative to time-consuming sample preparation techniques such as liquid-liquid extraction. Solid phase extraction (SPE) on disposable cartridges, dialysis or column switching are sample preparation techniques that can be fully automated and applied to enantioselective analysis in biological fluids. The selection of the most appropriate LC mode and chiral stationary phase for enantioseparations in bioanalysis is discussed and some aspects of these automated sample preparation procedures are compared, such as selectivity, detectability, elution of the analytes from the extraction sorbent, sample volume and analyte stability. [less ▲]

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See detailAutomated sample preparation-fractionation for the measurement of dioxins and related compounds in biological matrices: a review
Focant, Jean-François ULg; Pirard, Catherine; De Pauw, Edwin ULg

in Talanta (2004), 63(5), 1101-1113

This article reviews some of the recent developments in the extraction and clean-up areas of biological samples dedicated to dioxin and related compound analysis. A brief introduction on the major dioxin ... [more ▼]

This article reviews some of the recent developments in the extraction and clean-up areas of biological samples dedicated to dioxin and related compound analysis. A brief introduction on the major dioxin contamination events, which have occurred in the food chain, is given to illustrate the need of fast high throughput methods in case of crises. The emphasis of this paper is the method development based upon reliable instrumental extraction techniques for rapid sample processing and automation such as; supercritical fluid extraction (SFE), microwave-assisted extraction (MAE), pressurized liquid extraction (PLE) and, solid-phase extraction (SPE). The PLE and SPE are also discussed in conjunction with the use of a multi-column automated clean-up system that can accommodate up to 5 g of extracted lipids. The fractionation in sub-groups of analytes during the clean-up process allows the isolation of various types of toxicants from a single sample and illustrates the versatility of the system. An integrated extraction and clean-up instrument is finally presented in terms of feasibility and attainable sample turnover for the parallel processing of liquid and solid biological samples. (C) 2004 Elsevier B.V. All rights reserved. [less ▲]

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See detailAutomated SPE and clean-up for PBDEs in human blood
Focant, Jean-François ULg

Scientific conference (2011, June)

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See detailAutomated synthesis of [18F] FBEM for labeling of thiol containing compounds
Paris, Jérôme ULg; Thonon, David ULg; Kaisin, Geoffroy ULg et al

Poster (2011, September 01)

[18F]FBEM, i.e. N-[2-(4-[18F]fluorobenzamido)ethyl]maleimide, is a useful synthon employed for the specific radiolabeling of thiol containing compounds, including peptides and proteins. The aim of the ... [more ▼]

[18F]FBEM, i.e. N-[2-(4-[18F]fluorobenzamido)ethyl]maleimide, is a useful synthon employed for the specific radiolabeling of thiol containing compounds, including peptides and proteins. The aim of the present work was to develop a fast, reproducible and fully automated synthesis of this compound in order to improve its availabilty as well as for obvious radioprotection matters. [less ▲]

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See detailAutomated text categorization in a dead language. The detection of genres in Late Egyptian
Gohy, Stéphanie ULg; Martin Leon, Benjamin ULg; Polis, Stéphane ULg

in Polis, Stéphane; Winand, Jean (Eds.) Texts, Languages & Information Technology in Egyptology. Selected papers from the meeting of the Computer Working Group of the International Association of Egyptologists (Informatique & Égyptologie), Liège, 6-8 July 2010 (2013)

This paper is a first step in applying machine learning methods typical of Automated Text Catego-rization (ATC) for Automatic Genre Identification (AGI) in Late Egyptian, a language written in either ... [more ▼]

This paper is a first step in applying machine learning methods typical of Automated Text Catego-rization (ATC) for Automatic Genre Identification (AGI) in Late Egyptian, a language written in either hieroglyphic or hieratic scripts that is found in documents from Ancient Egypt dating from ca. 1350-700 BCE. The study is divided into three parts. After a general intro¬duction on AGI (§1), we introduce the levels of annotation that are integrated in the Ramses corpus and can be used when performing AGI on Late Egyptian (§2). In the following section (§3) we offer a brief survey of the types of features that have been discussed in the literature on AGI, before proceeding with three case studies where we apply supervised machine learning methods — namely the naïve Bayes classifier (§4.1), the Support Vector Machine (§4.2), and the Segment and Combine approach (§4.3) — to a selection of texts in the corpus. Their respective performances are tested using lexical, part-of-speech and inflectional features. [less ▲]

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See detailAutomated, High-Throughput, Multi-scale Assessment of Bone Morphology and Bone Competence
Mader, K.; Schneider, P.; Ruffoni, Davide ULg et al

in IFMBE Proceedings (2010), 31

Osteoporosis, the most prevalent degenerative disease in western societies, is characterized by a reduction in bone mass and altered architectural arrangement of bone tissue; however, how bone morphology ... [more ▼]

Osteoporosis, the most prevalent degenerative disease in western societies, is characterized by a reduction in bone mass and altered architectural arrangement of bone tissue; however, how bone morphology on different length scales contributes to overall bone strength and how mechanical stresses are translated into biochemical signals is still poorly understood. This study aims to establish a framework for the automated high-throughput assessment of bone morphology and bone competence on length scales ranging from cellular to organ. We developed automation tools to enable measurement, quantitative morphological analysis, and finite element (FE) modeling for murine femora that will be used on two inbred strains of mice and their respective crossings (> 2000 samples). Two separate 3D x-ray tomography measurements are made, one at low (mu CT) and one at high resolution (Syncrotron Radiation CT). From the low-resolution scans organ-scale characteristics are extracted and from the high-resolution, ultrastructural morphology. The former provides information on macroscopic bone structures and is used for FE modeling. The later provides the canal network and osteocyte lacunae phenotypes. We devised and implemented new morphometric measures to quantify individual shape parameters for these phenotypes, such as orientation, radial distribution, anisotropy, and point density. To integrate the results, we developed a set of software tools to register the different resolutions to each other and a database infrastructure to enable easy management and analysis of such a large volume of data. This database and web-based interface provides a platform for sharing results greatly simplifying the creation of future studies. The presented automated high-throughput assessment of bone morphology at different length scales (whole bone and cell level) provides the prerequisites for direct comparisons between the ultrastructure, whole bone geometry, and mechanical bone competence. In future studies, this will allow investigating how individual ultrastructural bone properties relate to the local stress/strain environment computed by FE. We aim to establish a true phenomics approach, by linking back these phenotypes to the different genotypes of the distinct mouse strains to isolate the genetic contribution for these phenotypes, which are relevant for skeletal integrity. In conclusion, we established a multi-scale framework for quantitative, genetic, high-throughput studies to explore 3D structure-function relationships from cell to organ using computed tomography and computational modeling. The database comprising these results will provide the complete picture of natural differences in healthy bone and provide a starting point for analyzing structurally caused variations in bone strength. At the same time, it will serve as a frame of reference for quantitatively investigating changes that occur in conditions of bone diseases such as osteoporosis. [less ▲]

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See detailAutomates et systèmes de numération
Charlier, Emilie ULg

Conference (2012, August)

Ce cours d'1h30 est accessible à un grand public de mathématiciens, y compris les enseignants du secondaire. Je commencerai par définir ce que sont les automates finis. J'introduirai les systèmes de ... [more ▼]

Ce cours d'1h30 est accessible à un grand public de mathématiciens, y compris les enseignants du secondaire. Je commencerai par définir ce que sont les automates finis. J'introduirai les systèmes de numération en général. Je m'attarderai sur le cas des bases entières, et montrerai les propriétés remarquables de calculs dans ces bases, notamment le calcul de l'addition et de la multiplication par une constante par automate fini. Ensuite, j'étendrai ces considérations à des numérations dites non-standard et aux systèmes de Pisot. Enfin, je définirai les numérations abstraites. [less ▲]

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See detailAutomates et systèmes de numération
Rigo, Michel ULg

in Bulletin de la Société Royale des Sciences de Liège (2005), 73

Ce survol introductif est basé sur une mini-conférence réalisée à la Société Royale des Sciences de Liège en avril 2004 et sur un exposé réalisé à l’IUFM de Reims en juin 2003 (Integrating Technologies ... [more ▼]

Ce survol introductif est basé sur une mini-conférence réalisée à la Société Royale des Sciences de Liège en avril 2004 et sur un exposé réalisé à l’IUFM de Reims en juin 2003 (Integrating Technologies into Mathematics Education). Nous y présentons divers systèmes de numération du point de vue de la théorie des langages formels. On s’attache dès lors à mettre en lumière les liens éventuels entre propriétés arithmétiques des nombres et propriétés syntaxiques de leurs représentations. La première partie de ce texte introduit en particulier la notion d’automate et quelques unes de ses applications. [less ▲]

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See detailAutomates et vérification
Wolper, Pierre ULg

in Encyclopédie de l'informatique et des systèmes d'information (2006)

La vérification de programmes consiste à analyser les comportements possibles de programmes en vue de déterminer s’ils seront toujours conformes à ce qui est attendu. Pour ce faire, les caractéristiques ... [more ▼]

La vérification de programmes consiste à analyser les comportements possibles de programmes en vue de déterminer s’ils seront toujours conformes à ce qui est attendu. Pour ce faire, les caractéristiques souhaitées des comportements sont exprimées formellement et confrontées, par des techniques mathématiques rigoureuses, à l’ensemble des comportements du programme à analyser. Dans ce contexte, les automates jouent un triple rôle. Tout d’abord, ils sont fréquemment utilisés en tant que langage de programmation simplifié pour décrire les programmes à analyser. Ensuite, ils servent de formalisme de description de propriétés de comportements, soit directement, soit par traduction à partir d’un langage logique. Finalement, ils s’avèrent très utiles en tant que formalisme de description d’ensembles infinis de valeurs. [less ▲]

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See detailAutomatic 1958-2007 daily weather pattern classification applied to an analysis of climatic conditions of wildfires in eastern Belgium
Erpicum, Michel ULg; Fettweis, Xavier ULg; Mabille, Georges ULg et al

Poster (2008, April)

The daily atmospheric circulation patterns classification is founded on a 100 km regular grid centred on Belgium. The geopotential heights of 500, 850 and 1000 hPa levels were extracted <br />from the ERA ... [more ▼]

The daily atmospheric circulation patterns classification is founded on a 100 km regular grid centred on Belgium. The geopotential heights of 500, 850 and 1000 hPa levels were extracted <br />from the ERA-40 database on the period 1958-2002 and from ECMWF operational analysis until the end of year 2007. The classification was based on a similarity index calculated on the orientation of exaggerated slopes of different daily geopotential fields. Wildfire occurrences were analyzed in April and September (which are the two months with the most frequent wildfire-days in Belgium) together with monthly frequencies and persistences of daily atmospheric circulation pattern classes as well as with yearly variability of weather climate conditions. [less ▲]

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See detailAn automatic adaptative remeshing for modelling of shear band
Bille, Jean Philippe; Charlier, Robert ULg; Dyduch, Marek

in Proc. of the 3rd European Conf. on Num. Meth. in Geotechnical Eng., ECONMIG'94 (1994, September)

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