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See detailMeasurement of selected halogenated contaminants in human serum and milk using GCxGC-IDTOFMS
Focant, Jean-François ULg; sjodin, Andreas; Turner, Wayman et al

in Organohalogen Compounds (2004)

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See detailMeasurement of selected polybrominated diphenyl ethers, polybrominated and polychlorinated biphenyls, and organochlorine pesticides in human serum and milk using comprehensive two-dimensional gas chromatography isotope dilution time-of-flight mass spectrometry
Focant, Jean-François ULg; Sjodin, Andreas; Turner, Wayman E. et al

in Analytical Chemistry (2004), 76(21), 6313-6320

A new method using comprehensive two-dimensional gas chromatography and isotope dilution time-of-flight mass spectrometry (GC x GC-IDTOFMS) for the simultaneous measurement of selected polychlorinated ... [more ▼]

A new method using comprehensive two-dimensional gas chromatography and isotope dilution time-of-flight mass spectrometry (GC x GC-IDTOFMS) for the simultaneous measurement of selected polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and brominated flame retardants is presented. In contrast to the reference methods based on classical GC/MS, a single injection of the extract containing all compounds of interest results in accurate identification and quantification. Using GC x GC ensures the chromatographic separation of most compounds, and TOFMS allows mass spectral deconvolution of coeluting compounds as well as the use of C-13-labeled internal standards for quantification. Isotope ratio measurements of the most intense ions for both native and labels ensure the required specificity. The use of this new method with an automated sample preparation procedure developed at the Centers for Disease Control and Prevention (CDC) for the analysis of human serum and milk compared favorably to conventional isotope-dilution one-dimensional gas chromatography-high-resolution mass spectrometty (GC-IDHRMS) for the different human serum and milk pools tested. The instrumental detection limits ranged between 0.5 pg/muL and 10 pg/muL and the method detection limits ranged between I and 15 pg/muL (N = 59 analytes). The reproducibility of the method was almost as good as with GC-IDHRMS, the relative standard deviations ranging between 1 and 11% for OCPs measured in human serum. OCP, PBDE, and PCB levels measured using the two methods were highly correlated, and the deviations between the two methods were below 20% for most analytes with concentrations above 1 ng/g milk lipids. [less ▲]

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See detailMeasurement of serum albumin by protein electrophoresis and bromocresol green methods in canine and equine patients
Ramery, Eve ULg; Bureau, Fabrice ULg

in Veterinary Clinical Pathology (2012, December), 41(4), 5

Background: Bromocresol green method (BCG) is routinely used in veterinary laboratories to measure albumin. A good agreement between BCG and electrophoresis (SPE) in healthy domestic animals is reported ... [more ▼]

Background: Bromocresol green method (BCG) is routinely used in veterinary laboratories to measure albumin. A good agreement between BCG and electrophoresis (SPE) in healthy domestic animals is reported. However, in human medicine, at low albumin and high globulin concentrations, BCG also binds to α- and β-globulins fractions. Surprisingly, there is no recent literature evaluating the BCG method in diseased domestic animals. Objective: The purpose of the present study was therefore to compare the serum albumin values obtained by SPE and BCG in canine and equine patients. Methods: Albumin measured by BCG and SPE was compared in the serum from 30 canine and 30 equine patients. Results: Good correlation was found (Spearman´s rho rs = 0.91 in dogs and 0.84 in horses). However, Altman and Bland analysis of results showed a positive bias of BCG with SPE (3.41 g/l in horses and 0.41 g/l in dogs) that increased when only hypoalbuminemic patients were considered (4.17 g/l in horses and 1.31 g/l in dogs). Conclusion: Results confirm that, despite good correlation, BCG method tends to overestimate albumin, especially in hypoalbuminemic patients. This is particularly evident in horses. [less ▲]

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See detailMeasurement of shrinkage and cracks associated to convective drying of soft materials by X-ray microtomography
Léonard, Angélique ULg; Blacher, Silvia ULg; Marchot, Pierre ULg et al

in Drying Technology (2004), 22(7), 1695-1708

Traditionally, the measurement of shrinkage occurring during drying is performed by destructive or poorly accurate techniques such as volume displacement methods. Cracks detection and quantification are ... [more ▼]

Traditionally, the measurement of shrinkage occurring during drying is performed by destructive or poorly accurate techniques such as volume displacement methods. Cracks detection and quantification are realised either by destructive techniques or sophisticated but expensive nondestructive ones (NMR imaging). X-ray microtomography in combination with image analysis provides an accurate, nondestructive and easy to use technique to determine simultaneously shrinkage and crack extent. Results reported in this article concern drying of wastewater sludges whose management will become a real challenge in the years to come. These results show a clear relation between drying kinetics and crack development. This could be related to the development of internal diffusional limitations inducing moisture gradients and mechanical stresses leading to cracks formation. [less ▲]

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See detailMeasurement of soil surfaces profiles with an optical displacement transducer.
Destain, Marie-France ULg; Verbrugge, Jean-Claude ULg

in Proceedings, 9th International Conference of the International Society for Terrain Vehicle Systems, held in Barcelona, Spain, 31 August-4September 1987. Volume 1. (1987), 1

Microrelief of seedbeds after two different soil tillages were measured with an optical displacement transducer. Measurements were made after sowing and on two successive dates. A complete statistical ... [more ▼]

Microrelief of seedbeds after two different soil tillages were measured with an optical displacement transducer. Measurements were made after sowing and on two successive dates. A complete statistical analysis was obtained by means of power spectra and autocorrelation functions. The authors suggest using the absolute value of the slope of the tangent at the origin of the autocorrelation function with the aim of analysing the behaviour of small particles in the scope of soil degradation [less ▲]

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See detailMeasurement of the 2s2p2(4P)3s 3P2 lifetime in N II by beam-foil-laser spectroscopy
Bastin, Thierry ULg; Baudinet-Robinet, Y.; Garnir, Henri-Pierre ULg et al

in Journal Physical II (1993), 3

An accurate value for the radiative lifetime of the 2s2p2(4P)3s3P2 level in N II has been obtained using the beam-foil-laser spectroscopy method. The result (T = 0.456 ± 0.020 ns ) is shorter than the ... [more ▼]

An accurate value for the radiative lifetime of the 2s2p2(4P)3s3P2 level in N II has been obtained using the beam-foil-laser spectroscopy method. The result (T = 0.456 ± 0.020 ns ) is shorter than the beam-foil lifetime values reported previously for the 3s' 3P term. No theoretical value for the lifetime of this term is available at the present time. [less ▲]

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See detailMeasurement of the 3s' 3p2 lifetime in N II by beam-foil-laser spectroscopy
Baudinet-Robinet, Y.; Bastin, Thierry ULg; Dumont, Paul-Dominique ULg et al

Poster (1993)

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See detailMeasurement of the force occuring at the impact of a non-lethal projectile with the Flexiforce sensor
Robbe, Cyril ULg; Nsiampa Ndompetelo, ULg; Papy, Alexandre

in 6th European Symposium on Non-Lethal Weapons 2011 proceedings (2011, May 16)

Force measurements are important to experimentally assess the effects of a non- lethal projectile on a human body. In addition they are also necessary to evaluate the bio-fidelity of a system regarding ... [more ▼]

Force measurements are important to experimentally assess the effects of a non- lethal projectile on a human body. In addition they are also necessary to evaluate the bio-fidelity of a system regarding PMHS (post mortem human subject) data. So far, as we can see in the literature, these measurements are usually achieved with an accelerometer placed inside the projectile. By assuming this projectile is perfectly rigid, the impact force can be calculated [1, 2]. However, the limitations are obvious: on the one hand the embedded accelerometer will change the projectile properties. On the other hand the force cannot directly be deduced for the deformable projectiles usually used nowadays. Therefore, a new system to measure impact force has to be developed. In this study, we propose to use the Flexiforce sensor, which is a cheap and very thin force sensor compatible with the expected measurement range [3]. The final objective is to realise an efficient force measurement on any kinetic energy non-lethal weapon (KENLW) projectile, using this particular sensor. We can find in the literature some static calibration [3,4]. As our application is highly dynamical, we started this study with the design and application of a dynamic calibration process. Then results from rigid projectiles (comparing to a classic KENLW projectile) impacting rigid targets (comparing to human body or a biofidelic surrogate) are collected and Flexiforce and accelerometer signals are compared (“rigid-rigid impacts). Finally, force measurements of projectiles impacting deformable surfaces (comparing to the projectile ) with the Flexiforce sensor are achieved (“rigid-soft impacts”). [less ▲]

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See detailMeasurement of the magnetic field inside the holes of a drilled bulk high-Tc superconductor
Lousberg, Grégory ULg; Fagnard, Jean-François ULg; Noudem, Jacques G et al

in Superconductor Science and Technology (2009), 22

We use macroscopic holes drilled in a bulk YBCO superconductor to probe its magnetic properties in the volume of the sample. The sample is subjected to an AC magnetic flux with a density ranging from 30 ... [more ▼]

We use macroscopic holes drilled in a bulk YBCO superconductor to probe its magnetic properties in the volume of the sample. The sample is subjected to an AC magnetic flux with a density ranging from 30 to 130 mT and the flux in the superconductor is probed by miniature coils inserted in the holes. In a given hole, three different penetration regimes can be observed: (i) the shielded regime, where no magnetic flux threads the hole; (ii) the gradual penetration regime, where the waveform of the magnetic field has a clipped sine shape whose fundamental component scales with the applied field; and (iii) the flux concentration regime, where the waveform of the magnetic field is nearly a sine wave, with an amplitude exceeding that of the applied field by up to a factor of two. The distribution of the penetration regimes in the holes is compared with that of the magnetic flux density at the top and bottom surfaces of the sample, and is interpreted with the help of optical polarized light micrographs of these surfaces. We show that the measurement of the magnetic field inside the holes can be used as a local characterization of the bulk magnetic properties of the sample. [less ▲]

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See detailMeasurement of the magnetic flux threading holes of drilled superconductors
Lousberg, Grégory ULg

Poster (2007, September)

Article associé : Measurement of the magnetic field inside the holes of a drilled bulk high-Tc superconductor

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See detailMeasurement of the magnetic hysteresis cycle of bulk superconductor / ferromagnet hybrids
Philippe, Matthieu ULg; Fagnard, Jean-François ULg; Wera, Laurent ULg et al

Conference (2013, November 07)

Large grain, bulk YBa2Cu3O7-δ (YBCO) high temperature superconductors (HTS) can be potentially used as powerful permanent magnets for magnetic levitation. The magnetic flux distribution above a bulk HTS ... [more ▼]

Large grain, bulk YBa2Cu3O7-δ (YBCO) high temperature superconductors (HTS) can be potentially used as powerful permanent magnets for magnetic levitation. The magnetic flux distribution above a bulk HTS magnet, however, is strongly non-uniform compared to the rather flat distribution above a ferromagnet. In the present work, we study experimentally how cylindrical pieces of FeNi soft ferromagnetic alloys can be combined with a cylindrical, bulk, large grain YBCO superconductor to improve the distribution of the trapped field at the surface or its average value through the volume of the sample. The magnetic properties of each hybrid structure are measured at 77 K under axial magnetic field up to 3 T. The remanent induction distribution near the top and bottom surfaces is determined by miniature Hall probe mapping. Pick-up coils wound around the superconductor are used to measure the average flux density inside the superconductor. This technique relies on low level voltage measurements (typically a few microvolts) and allows non-destructive measurement of the average magnetic hysteresis curve of the entire bulk superconductor. [less ▲]

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See detailMeasurement of the partial pressure of CO2 in bulk sea ice
Geilfus, Nicolas-Xavier ULg; Verbeke, Véronique; Delille, Bruno ULg et al

Poster (2007, July)

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See detailMeasurement of the power output during the acceleration phase of all-put arm cranking exercise
Vanderthommen, Marc ULg; Francaux, Marc; Johnson, D. et al

in International Journal of Sports Medicine (1997), 18

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See detailMeasurement of the tibial subchondral bone mineral density: a potential tool for diagnosis and monitoring of knee osteoarthrits
Bruyère, Olivier ULg; Zegels, Brigitte ULg; Dardenne, Charles-Bernard et al

in Clinical Rheumatology (2001), 5(Suppl.1), 411

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See detailMeasurement of the tibial subchondral bone mineral density: a potential tool for diagnosis and monitoring of knee osteoarthrits
Bruyère, Olivier ULg; Zegels, Brigitte ULg; Dardenne, Charles-Bernard et al

in Osteoarthritis and Cartilage (2001), 9(Suppl.B), 61

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See detailMeasurement of tomato firmness by using a non-destructive mechanical sensor
Lesage, Patrick; Destain, Marie-France ULg

in Postharvest Biology & Technology (1996), 8

A non-destructive mechanical sensor (Cantifruit) was designed to measure the firmness of tomatoes. It consists of a small plunger constrained to penetrate slightly into the fruits, by using an accurate ... [more ▼]

A non-destructive mechanical sensor (Cantifruit) was designed to measure the firmness of tomatoes. It consists of a small plunger constrained to penetrate slightly into the fruits, by using an accurate lever mechanism. A highly significant correlation exists between firmness measurements performed with this device and the Stable Micro Systems (SMS), fitted with the same plunger dimaeter. Using the Cantifruit, data related to firmness variability and changes are easily obtained. The firmness of tomatoes varies about 12 % around its circumference. In a single lot of tomatoes picked at the same time, the variability may exceed 25 %. If the tomatoes are stored at 4-5 °C and 92-99 % relative humidity (RH), their firmness decreases by about 20 % over ten days. [less ▲]

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See detailMeasurement of Total Respiratory Impedance in Calves by the Forced Oscillation Technique
Gustin, Pascal ULg; Dhem, A.R.; Lomba, Fernand et al

in Journal of Applied Physiology (Bethesda, Md. : 1985) (1988), 64(5), 1786-1791

We have determined the resistance (Rrs) and the reactance (Xrs) of the total respiratory system in unsedated spontaneously breathing calves at various frequencies. A pseudorandom noise pressure wave was ... [more ▼]

We have determined the resistance (Rrs) and the reactance (Xrs) of the total respiratory system in unsedated spontaneously breathing calves at various frequencies. A pseudorandom noise pressure wave was produced at the nostrils of the animals by means of a loudspeaker adapted to the nose by a tightly fitting mask. A Fourier analysis of the pressure in the nostrils and flow signals yielded mean Rrs and Xrs, over 16 s, at frequencies of 2-26 Hz. A good correlation was found between values of pulmonary resistances measured by the isovolume method at the respiratory frequency of animals and values obtained at a frequency of 6 Hz by use of our technique. The linearity of the respiratory system, the reproducibility of the technique, and the effects of upper airways on results have been studied. In healthy calves, Rrs increases with frequency. Mean resonant frequency is 7.5 Hz. Bronchospasm was induced in six calves by administration of intravenous organophosphates. Rrs tended to decrease with increasing frequency. Resonant frequency exceeded 26 Hz. All parameters returned to initial values after administration of atropine. In healthy calves, atropine produces a decrease in Rrs, especially at low frequencies. Values of resonant frequency are not modified. [less ▲]

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See detailMeasurement of Total Respiratory Impedance in Dogs by the Forced Oscillation Technique
Clercx, Cécile ULg; Gustin, Pascal ULg; Landser, F. J. et al

in Veterinary Research Communications (1993), 17(3), 227-239

The resistance (Rrs) and reactance (Xrs) of the total respiratory system were determined at various frequencies in 14 healthy conscious beagle dogs. A pseudorandom noise pressure wave was produced at the ... [more ▼]

The resistance (Rrs) and reactance (Xrs) of the total respiratory system were determined at various frequencies in 14 healthy conscious beagle dogs. A pseudorandom noise pressure wave was produced at the nostrils of the animals by means of a loudspeaker adapted to the nose by a tightly fitting mask. A Fourier analysis of the pressure and flow signals yielded mean Rrs and Xrs, over 16 s, at frequencies from 2 to 26 Hz. The influence of the posture of the dog, the position of its head, the linearity of the respiratory system, the reproducibility of the method and the effects of upper and lower airway obstructions were studied. In sitting and standing healthy dogs with the head in the extended position, Rrs values increased progressively with frequency from 5.4 +/- 0.4 (SEM) cmH2O L-1s at 6 Hz up to 8.8 +/- 0.7 cmH2O L-1s at 26 Hz, the mean resonant frequency being 6.1 +/- 0.5 Hz. No significant differences were observed between measurements performed with the head in the normal or the extended position. In a recumbent posture, all Rrs values were increased but Rrs was still dependent on the frequency in the same way (7.1 +/- 0.7 cmH2O L-1s at 6Hz up to 10.0 +/- 0.5 cmH2O L-1s at 26 Hz). Tracheal compression also induced higher Rrs values without changes in the frequency dependence or in the resonant frequency. In anaesthetized dogs, airway obstruction was induced by inhalation of histamine (4 mg/ml for 5 min; the Rrs values tended to decrease with increasing frequency, and the resonant frequency was markedly increased [less ▲]

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