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See detailQuantitative dilatometric analysis of intercritical annealing in a low-silicon TRIP steel
Zhao, Lie; Kop, T. A.; Rolin, Valéry et al

in Journal of Materials Science (2002), 37

In this work, an evaluation method to calculate the austenite fraction during continuous heating and isothermal annealing from dilatometric data is proposed. By means of a single reference measurement to ... [more ▼]

In this work, an evaluation method to calculate the austenite fraction during continuous heating and isothermal annealing from dilatometric data is proposed. By means of a single reference measurement to determine a scaling factor correcting for experimental errors, a framework is created to determine the austenite fraction as a function of time and temperature. In the evaluation of the dilatometric data the effect of the changing carbon concentration in austenite phase is taken into account. The method is applied to dilatometric data for a 0.16C-1.5Mn-0.4Si (wt%) low-silicon transformation induced plasticity (TRIP) multiphase steel. Three typical dilatometric data are obtained by heating the material to 750°C, 800°C or 900°C, which leads to three different microstructures consisting of (1) ferrite, cementite and austenite, (2) ferrite and austenite and (3) full austenite, respectively. The calculated results using the proposed new method are compared with the results from thermodynamic analysis and those from quantitative microscopic analysis. Significant inter-test discrepancies are observed. [less ▲]

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See detailQuantitative dynamics of PCB transfer from mother to pup during lactation in UK grey seals Halichoerus grypus
Debier, Cathy; Pomeroy, Paddy P.; Dupont, Cédric et al

in Marine Ecology-Progress Series (2003), 247

PCB contamination was measured in the milk and serum of grey seal Halichoerus grypus mothers and in the serum of their pups sampled from 2 to 5 times between parturition and weaning on the Isle of May ... [more ▼]

PCB contamination was measured in the milk and serum of grey seal Halichoerus grypus mothers and in the serum of their pups sampled from 2 to 5 times between parturition and weaning on the Isle of May, Scotland, in 1998 and 2000. Blubber biopsies were also taken from the lactating females at early and late lactation in 2000. Concentrations of PCBs in milk stayed constant during the first part of lactation (0.31 +/- 0.17 mug g milk(-1)) and then increased at late lactation (0.67 +/- 0.42 mug g milk(-1)). Curiously, it did not follow the changes of milk lipid content, which increased at early lactation and then stayed constant until the end of the nursing period. As a result, even when expressed per unit of milk lipids, PCBs underwent a rise at the end of lactation. The changes in milk PCBs were accompanied by similar dynamics in maternal serum as well as in pup serum. Increased concentrations of PCBs at late lactation in serum and milk may be explained in part by the changes observed in maternal blubber. PCB levels increased significantly between early and late lactation in inner blubber, suggesting that PCBs are less easily mobilised from blubber than lipids. At late lactation, the retention capacity of the reduced blubber layer for PCBs might have reached its maximum. The mobilization of less polar lipids from blubber might also occur at this stage. In both cases, this could result in a higher mobilization of PCBs at this time. While inner blubber was significantly less concentrated than outer blubber at early lactation (1.26 +/- 0.72 mug g lipids(-1) in inner blubber vs 3.16 +/- 1.34 mug g lipids(-1) in outer blubber), these variations disappeared at late lactation (3.24 +/- 2.60 mug g lipids(-1) in inner blubber vs 3.59 +/- 1.46 mug g(-1) lipids in outer blubber). Newborn pups already had significantly higher serum levels of PCBs than their mothers, revealing an important placental transfer (11.9 +/- 7.0 ng ml serum(-1) in pups vs 6.7 +/- 3.5 ng ml serum(-1) in mothers). These differences were even greater in late lactation, due to the ingestion of milk (27.9 +/- 18.1 ng ml serum(-1) in pups vs 12.2 +/- 7.2 ng ml serum(-1) in mothers). As lactation progressed, PCB levels in pup serum increased exponentially as compared to the levels in the serum of their mothers. [less ▲]

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See detailQuantitative estimates of the constraints on solar-like models imposed by observables
Ozel, Nesibe; Dupret, Marc-Antoine ULg; Baglin, A.

in Astronomy and Astrophysics (2011), 532

Context. Seismic parameters such as the large Δ[SUB]0[/SUB] and small δ[SUB]02[/SUB] frequency separations are now being measured in a very large number of stars and begin to be used to test the physics ... [more ▼]

Context. Seismic parameters such as the large Δ[SUB]0[/SUB] and small δ[SUB]02[/SUB] frequency separations are now being measured in a very large number of stars and begin to be used to test the physics of stellar models. <BR /> Aims: We estimate the influence of different observed quantities (oscillation frequencies, interferometry, etc.) and the impact of their accuracy in constraining stellar model parameters. <BR /> Methods: To relate the errors in observed quantities to the precision of the theoretical model parameters, we analyse the behaviour of the χ[SUP]2[/SUP] fitting function around its minimum using the singular value decomposition (SVD) formalism. A new indicator called "weighting" quantifies the relative importance of observational constraints on the determination of each physical parameter individually. These tools are applied to a grid of evolutionary sequences for solar-like stellar models with varying age and mass, and to a real case: HD 49933 - a typical case for which seismic observations are available from space using CoRoT. <BR /> Results: The mass ℳ is always the best determined parameter. The new indicator "weighting" allows us to rank the importance of the different constraints: the mean large separation Δ[SUB]0[/SUB], the radius R/R[SUB]&sun;[/SUB], the mean small separation δ[SUB]02[/SUB], the luminosity L/L[SUB]&sun;[/SUB], the effective temperature T[SUB]eff[/SUB]. If the metallicity and age parameters are known, for example in an open cluster, using either individual or mean frequency separations yields the same uncertainties for masses less than 1.1 M[SUB]&sun;[/SUB]. For HD 49933 the combination of ℳ and Y[SUB]0[/SUB]: ℳ[SUP]2[/SUP]Y[SUB]0[/SUB] is well determined because of their correlation. However, they are poorly constrained individually. The frequency difference δ[SUB]01[/SUB], if known with an error of about 0.3%, can determine the size of the convective core overshooting with about 3% accuracy. Appendices A and B are available in electronic form at <A href="http://www.aanda.org">http://www.aanda.org</A> [less ▲]

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See detailQuantitative estimation of chimerism in mice using microsatellite markers
Delhaise, F.; Zhao, X.; Dessy, F. et al

in Molecular Reproduction and Development (1993), 34(2), 127-132

An embryonic stem cell line was established from SV129 mouse blastocysts and used to generate chimeric mice by injection into OF1 blastocysts; 18 out of the 30 resulting offspring appeared chimeric as ... [more ▼]

An embryonic stem cell line was established from SV129 mouse blastocysts and used to generate chimeric mice by injection into OF1 blastocysts; 18 out of the 30 resulting offspring appeared chimeric as judged from their coat color patterns, and 3 of the 13 males proved to be germ-line chimeras as they transmitted the SV129 agouti phenotype to all or part of their offspring. The degree of chimerism of these males was evaluated for different tissues using polymorphic microsatellite markers amplified by the polymerase chain reaction. It was shown that these new markers can be effectively used to quantitatively estimate levels of chimerism. The CKMM (creatine kinase, muscle) microsatellite system was used to distinguish the SV129 from the OF1 genotype. In all performed tests, the correlation between DNA ratio and signal ratio, expressed as a base 10 logarithm, was shown to exceed or equal 0.98 for known DNA ratios (SV129/OF1) ranging from 1/99 to 99/1. Linear calibration methods were used to predict the % SV129 DNA of a test sample based on the obtained signal ratio. The accuracy of the prediction was evaluated by performing repeated measurements. Differences among three repeated estimates ranged from 2 to 17% for a given sample. Microsatellite systems should be very useful to monitor chimerism involving strains that can not be discerned with coat color or biochemical markers. This will be particularly important when ES methodology becomes available in species other than mice. [less ▲]

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See detailQuantitative estimation of estrogen and androgen receptor-immunoreactive cells in the forebrain of neonatally estrogen-deprived male rats.
Bakker, Julie ULg; Pool, C. W.; Sonnemans, M. et al

in Neuroscience (1997), 77(3), 911-9

Using quantitative immunocytochemical procedures, the total number of estrogen and androgen receptors was estimated in a large number of hypothalamic and limbic nuclei of male rats, in which brain ... [more ▼]

Using quantitative immunocytochemical procedures, the total number of estrogen and androgen receptors was estimated in a large number of hypothalamic and limbic nuclei of male rats, in which brain estrogen formation was inhibited neonatally by treatment with the aromatase inhibitor 1,4,6-androstatriene-3,17-dione. The highest densities of estrogen receptor immunoreactivity were observed in the periventricular preoptic area and the medial preoptic area. Neonatally estrogen-deprived males showed a higher estrogen receptor immunoreactivity than control males in the periventricular preoptic area and the ventrolateral portion of the ventromedial nucleus of the hypothalamus, i.e. those brain areas in which sex differences have been reported, with female rats showing a greater estrogen binding capacity than male rats. The highest densities of androgen receptor immunoreactivity were found in the septohypothalamic nucleus, the medial preoptic area, the posterior division of the bed nucleus of the stria terminalis and the posterodorsal division of the medial amygdaloid nucleus. No significant differences in distribution or total numbers of androgen receptors were found between neonatally estrogen-deprived males and control males. These findings suggest that neonatal estrogens, derived from the neural aromatization of testosterone, are involved in the sexual differentiation of the estrogen receptor system in the periventricular preoptic area and the ventromedial hypothalamus. The role of neonatal estrogens in the development of the forebrain androgen receptor system is less clear. [less ▲]

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See detailQuantitative evaluation of fluid resuscitation in burn children : a retrospective study.
ROUSSEAU, Anne-Françoise ULg; LEDOUX, Didier ULg; RICHARD, Patrick et al

in Burns : Journal of the International Society for Burn Injuries (2011), 37(suppl 1), 12

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See detailQuantitative Evaluation of Imputities in Ionic Liquids
Robert, Thierry ULg; Olivier-Bourbigou, Hélène; Gilbert, Bernard ULg

Poster (2010, March)

Since several years, our laboratory is studying the acidity in ionic liquids and showed that very acidic levels can be reached in these media when a strong acid is added. These acidity levels were ... [more ▼]

Since several years, our laboratory is studying the acidity in ionic liquids and showed that very acidic levels can be reached in these media when a strong acid is added. These acidity levels were determined using Hammett acidity1 (spectroscopic method) and Strehlow acidity2 (potentiometric method) measurements. Considering the attainable acidity levels, it turns out that the purity of these ionic solvents is very critical because all impurities (i.e methylimidazole, water, acetone, chloride …) can act as (strong) bases. Therefore, it is imperative to quantify these impurities to obtain reproducible results. [less ▲]

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See detailQuantitative evaluation of the post-Mount Pinatubo NO2 reduction and recovery, based on 10 years of Fourier transform infrared and UV-visible spectroscopic measurements at Jungfraujoch
De Mazière, Martine; Van Roozendael, Michel; Hermans, Christian et al

in Journal of Geophysical Research (1998), 103(D9), 10849-10858

The colocation of two technically different instruments for ground-based remote sensing of NO2 total column amounts at the primary Network for the Detection of Stratospheric Change Alpine station of the ... [more ▼]

The colocation of two technically different instruments for ground-based remote sensing of NO2 total column amounts at the primary Network for the Detection of Stratospheric Change Alpine station of the Jungfraujoch (46.5°N, 8.0°E) has been exploited for mutual validation of the long-term NO2 time series from both instruments and for a quantitative evaluation of the impact of the Mount Pinatubo eruption on the NO2 abundance above this northern mid-latitude observatory. The two techniques are high-resolution Fourier transform infrared solar absorption spectrometry and zenith-sky differential optical absorption spectroscopy in the UV visible. The diurnal variation of NO2 has been simulated by a simple photochemical model that allows a comparison between the data from the two techniques. This model is shown to reproduce the observed morning to evening ratios to 2.3%, on average, which is fully adequate for the needs of this study. From the 1985–1996 combined time series of NO2 morning and evening abundances, it has been concluded that the enhanced aerosol load injected into the stratosphere by Mount Pinatubo caused a maximum NO2 reduction above the Jungfraujoch by 45% in early January 1992 that died out quasi-exponentially to zero by the beginning of 1995. [less ▲]

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See detailQuantitative feed restriction programs for broiler chickens
Everaert, Nadia ULg; Buyse, Johan

in Proceedings of the 19th European Symposium on Poultry Nutrition (2013)

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See detailQuantitative food webs of herbivore and related beneficial community in non–crop and crop habitats
Alhmedi, Ammar; Haubruge, Eric ULg; D’Hoedt, Sandrine et al

in Biological Control (2011), 58

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See detailQuantitative gait assessment using an accelerometer technology as a predictive tool of falls among nursing home residents: a 6-month prospective study
Bruyère, Olivier ULg; Detalle, Anne-Sophie; Demonceau, Marie ULg et al

in Osteoporosis International (2013, April), 24(Suppl.1), 210

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See detailQuantitative gas chromatography - mass spectrometry profiling of volatile organic compounds produced by barley (Hordeum distichon L.) roots according to plant age
Delory, Benjamin ULg; Delaplace, Pierre ULg; du Jardin, Patrick ULg et al

Poster (2014, February 07)

In chemical ecology, the roles played by root-emitted volatile organic compounds (VOCs) in biotic interactions and the quantitative analysis of such chemicals in root tissues remain poorly documented. In ... [more ▼]

In chemical ecology, the roles played by root-emitted volatile organic compounds (VOCs) in biotic interactions and the quantitative analysis of such chemicals in root tissues remain poorly documented. In this context, this study aims at developing a fully automated analytical methodology allowing both identification and accurate quantification of VOCs produced by roots of a monocotyledon plant species. Briefly, VOC emitted by crushed barley roots are successively trapped by dynamic headspace sampling on Tenax TA adsorbents, thermally desorbed and cryofocused, separated by gas chromatography (GC) and finally analysed by mass spectrometry (MS) in both SCAN and selected ion monitoring modes. Results show that barley roots mainly produce four volatile aldehydes, namely hexanal, (E)-hex-2-enal, (E)-non-2-enal and (E,Z)-nona-2,6-dienal. These molecules are well-known linoleic (C18:2) and linolenic (C18:3) acid derivatives produced via the lipoxygenase and the hydroperoxide lyase pathways of higher plants. Our findings contrast with analyses documented on aboveground barley tissues that mainly emit C6 aldehydes, alcohols and their derivative esters. Moreover, preliminary results indicate quantitative changes in the volatile profile contained in barley roots according to plant age. Multivariate statistical analyses are currently underway to quantitatively assess these changes using plants at five selected developmental stages ranging from germination to the end of tillering. [less ▲]

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See detailQuantitative interpretation of atmospheric carbon records over the last glacial termination
Köhler, Peter; Fischer, Hubertus; Munhoven, Guy ULg et al

in Global Biogeochemical Cycles (2005), 19(4), 4020

The glacial/interglacial rise in atmospheric pCO(2) is one of the best known changes in paleoclimate research, yet the cause for it is still unknown. Forcing the coupled ocean-atmosphere-biosphere box ... [more ▼]

The glacial/interglacial rise in atmospheric pCO(2) is one of the best known changes in paleoclimate research, yet the cause for it is still unknown. Forcing the coupled ocean-atmosphere-biosphere box model of the global carbon cycle BICYCLE with proxy data over the last glacial termination, we are able to quantitatively reproduce transient variations in pCO(2) and its isotopic signatures (delta C-13, Delta C-14) observed in natural climate archives. The sensitivity of the Box model of the Isotopic Carbon cYCLE ( BICYCLE) to high or low latitudinal changes is comparable to other multibox models or more complex ocean carbon cycle models, respectively. The processes considered here ranked by their contribution to the glacial/interglacial rise in pCO(2) in decreasing order are: the rise in Southern Ocean vertical mixing rates (> 30 ppmv), decreases in alkalinity and carbon inventories (> 30 ppmv), the reduction of the biological pump (similar to 20 ppmv), the rise in ocean temperatures (15 - 20 ppmv), the resumption of ocean circulation (15 - 20 ppmv), and coral reef growth (< 5 ppmv). The regrowth of the terrestrial biosphere, sea level rise and the increase in gas exchange through reduced sea ice cover operate in the opposite direction, decreasing pCO(2) during Termination I by similar to 30 ppmv. According to our model the sequence of events during Termination I might have been the following: a reduction of aeolian iron fertilization in the Southern Ocean together with a breakdown in Southern Ocean stratification, the latter caused by rapid sea ice retreat, trigger the onset of the pCO(2) increase. After these events the reduced North Atlantic Deep Water (NADW) formation during the Heinrich 1 event and the subsequent resumption of ocean circulation at the beginning of the Bolling-Allerod warm interval are the main processes determining the atmospheric carbon records in the subsequent time period of Termination I. We further deduce that a complete shutdown of the NADW formation during the Younger Dryas was very unlikely. Changes in ocean temperature and the terrestrial carbon storage are the dominant processes explaining atmospheric d13C after the Bolling-Allerod warm interval. [less ▲]

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See detailQuantitative M-Mode and Two-Dimensional Echocardiography in Calves
Amory, Hélène ULg; Jakovljevic, S.; Lekeux, Pierre ULg

in Veterinary Record : Journal of the British Veterinary Association (1991), 128(2), 25-31

A standardised echocardiographic protocol was applied to 18 healthy calves for the estimation of 51 anatomical and functional cardiac variables. These variables were measured in a long axis and a short ... [more ▼]

A standardised echocardiographic protocol was applied to 18 healthy calves for the estimation of 51 anatomical and functional cardiac variables. These variables were measured in a long axis and a short axis view of the heart, and both two-dimensional and cursor-directed time-motion (M-) modes were used. The repeatability of each of the measurements was estimated by comparing values obtained twice within 24 hours, and most of the 51 variables showed a high degree of repeatability. Statistical analysis revealed a close correlation between cardiac measurements taken post mortem and by in vivo echocardiography, and between the echocardiographic values obtained in different scanning planes of the heart or ultrasonic modes, indicating that quantitative echocardiography is a reliable technique in calves. [less ▲]

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See detailQuantitative measurement of metal ions concentration of proteins separated by electrophoresis
Weber, Georges ULg; Strivay, David ULg; Menendez, M. et al

in International Journal of PIXE (1996), 1-2

This communication is devoted to nature determination and quantification by PIXE of metals contained in proteins after their separation by PolyAcrylamide Gel Electrophoresis (PAGE). After the ... [more ▼]

This communication is devoted to nature determination and quantification by PIXE of metals contained in proteins after their separation by PolyAcrylamide Gel Electrophoresis (PAGE). After the electrophoresis, the gel is dried and each track is scanned with a 2.5 MeV proton beam which triggers metal X-ray fluorescence and then, allows to determine the type of metals contained in an electrophoretic band. For quantitative determination of the amount of the metal contained inside the band, the characteristic X-ray peak area is compared with those obtained with polyacrylamide gels doped with the same metal. The normalization has been achieved by using RBS measurements on the gel itself. The procedure presented seems to be a very useful multielementary method for the metal content analysis and for the determination of the metal amounts inside proteins after their separation by electrophoresis. Furthermore it allows to check if metals remain bound to proteins. [less ▲]

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See detailQuantitative methods for food allergens: a review.
Kirsch, Stéphanie ULg; Fourdrilis, Séverine ULg; Dobson, Rowan ULg et al

in Analytical and Bioanalytical Chemistry (2009), 395

The quantitative detection of allergens in the food chain is a strategic health objective as the prevalence of allergy continues to rise. Food allergenicity is caused by proteins either in their native ... [more ▼]

The quantitative detection of allergens in the food chain is a strategic health objective as the prevalence of allergy continues to rise. Food allergenicity is caused by proteins either in their native form or in forms resulting from food processing. Progress in mass spectrometry greatly opened up the field of proteomics. These advances are now available for the detection and the quantification of traces of allergenic proteins in complex mixtures, and complete the set of biological tests used until now, such as ELISA or PCR. We review methods classified according to their ability to simultaneously quantify and identify allergenic proteins and underline major advances in the mass-spectrometric methods. [less ▲]

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