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See detailEstimated energy balance in the jovian upper atmosphere during an auroral heating event
Melin, Henrik; Miller, Steve; Stallard, Tom et al

in Icarus: International Journal of Solar System Studies (2006), 181(1), 256-265

We present an analysis of a series of observations of the auroral/polar regions of Jupiter, carried out between September 8 and 11, 1998, making use of the high-resolution spectrometer, CSHELL, on the ... [more ▼]

We present an analysis of a series of observations of the auroral/polar regions of Jupiter, carried out between September 8 and 11, 1998, making use of the high-resolution spectrometer, CSHELL, on the NASA InfraRed Telescope Facility (IRTF), Mauna Kea, Hawaii; these observations spanned an "auroral heating event." This analysis combines the measured line intensities and ion velocities with a one-dimensional model vertical profile of the jovian thermosphere/ionosphere. We compute the model line intensities both assuming local thermodynamic equilibrium (LTE) and, relaxing this condition (non-LTE), through detailed balance calculations, in order to compare with the observations. Taking the model parameters derived, we calculate the changes in heating rate required to account for the modelled temperature profiles that are consistent with the measured line intensities. We compute the electron precipitation rates required to give the modelled ion densities that are consistent with the measured line intensities, and derive the corresponding Pedersen conductivities. We compute the changes in heating due to Joule heating and ion drag derived from the measured ion velocities, and modelled conductivities, making use of ion-neutral coupling coefficients derived from a 3-D global circulation model. Finally, we compute the cooling due to the downward conduction of heat and the radiation-to-space from the H-3(+) molecular ion and hydrocarbons. Comparison of the various heating and cooling terms enables us to investigate the balance of energy inputs into the auroral/polar atmosphere. Increases in Joule heating and ion drag are sufficient to explain the observed heating of the atmosphere; increased particle precipitation makes only a minor heating contribution. But local cooling effects-predominantly radiation-to-space-are shown to be too inefficient to allow the atmosphere to relax back to pre-event thermal conditions. Thus we conclude that this event provides observational, i.e. empirical, evidence that heat must be transported away from the auroral/polar regions by thermally or mechanically driven winds. (c) 2005 Elsevier Inc. All rights reserved. [less ▲]

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See detailEstimated glomerular filtration rate
Delanaye, Pierre ULg; Cavalier, Etienne ULg; Krzesinski, Jean-Marie ULg

in Annals of Internal Medicine (2007), 146(1), 74-74

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See detailEstimated heterogeneity of phenotypic variance of test-day yield with a structural variance model
Gengler, Nicolas ULg; Wiggans, George; Gillon, Alain ULg

in Journal of Dairy Science (2004), 87

First-lactation test-day milk, fat, and protein yields from New York, Wisconsin, and California herds from 1990 through 2000 were adjusted additively for age and lactation stage. A random regression model ... [more ▼]

First-lactation test-day milk, fat, and protein yields from New York, Wisconsin, and California herds from 1990 through 2000 were adjusted additively for age and lactation stage. A random regression model with thirdorder Legendre polynomials for permanent environmental and genetic effects was used. The model included a random effect with the same polynomial regressions for 2 yr of calvings within herd (herd-time effect) to provide herd-specific lactation curves that can change every 2 yr. (Co)variance components were estimated using expectation-maximization REML simultaneously with phenotypic variances that were modeled using a structural variance model. Maximum heritability for test-day milk yield was estimated to be ∼20% around 200 to 250 d in milk; heritabilities were slightly lower for test-day fat and protein yields. Herd-time effects explained 12 to 20% of phenotypic variance and had the greatest impact at start of lactation. Variances of test-day yields increased with time, subclass size, and milking frequency. Test month had limited influence on variance. Variance increased for cows in herds with low and high milk yields and for early and late lactation stages. Repeatabilities of variances observed for a given class of herd, test-day, and milking frequency were 14 to 17% across nested variance subclasses based on lactation stage. [less ▲]

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See detailEstimated Subglottic Pressure Evaluation According to Vocal Pathology. Study on 418 Patients
Morsomme, Dominique ULg; Chareix, Hélène; FINCK, Camille ULg et al

Conference (2014, May 31)

Estimated subglottic pressure (ESGP) is part of the aerodynamic measurements included in the vocal profile. It is an indication of vocal effort and can guide the therapist in his clinical approach. We aim ... [more ▼]

Estimated subglottic pressure (ESGP) is part of the aerodynamic measurements included in the vocal profile. It is an indication of vocal effort and can guide the therapist in his clinical approach. We aim to examine the clinical interest of the ESGP by observing its values according to voice pathology, age, gender and sound pressure level. We also examine the relationships between PSGE, DSI and VHI. Method:The study includes 418 patients (M:118/W:300). Each patient’s file consists of VLS, acoustic, aerodynamic and perceptual measures. The ESGP was collected through the Phonatory Aerodynamic System Model 6600 (KayPentax). Patients produced 3 sequences of / ipipi / at low (IL), conversational (IC) and high (IH) intensity. Patients were grouped according to the ENT’s diagnosis. Results: Patients without vocal lesions (MTD) had a significantly lower ESGP compared to patients with nodules, polyps, inflammation, edema (IL, IC), cysts (IC) or scar (IC). Patients with vocal fold atrophy had a lower ESGP than those suffering from nodules and polyps at conversational and high intensity, but were not differentiated at low intensity. Amongst patients without lesions (MTD), a positive correlation appeared between ESGP and intensity; which was not the case for patients with lesions. At high intensity, men had a significantly higher ESGP than women. At low intensity, we noted a positive correlation between the VHI scores and ESGP levels. At low and conversational intensity, we observed a negative correlation between DSI and ESGP scores. Conclusion: This study highlights the importance of considering ESGP in the vocal profile. As expected, patients with vocal pathology produce high ESGP. However, the correlations between intensity and ESGP vary depending on the patient's pathology. In addition, ESPG values allow the clinician to distinguish MTD and healthy patients and thus could help the therapist in his clinical approach. [less ▲]

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See detailEstimates of genetic parameters among body condition score and calving traits in first parity Canadian Ayrshire cows
Bastin, Catherine ULg; Loker, Sarah; Gengler, Nicolas ULg et al

in Book of Abstracts of the 60th Annual Meeting of the European Association for Animal Production (2009, August)

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See detailEstimates of genetic parameters among body condition score and fertility traits in first-parity Canadian cows
Bastin, Catherine ULg; Loker, Sarah; Gengler, Nicolas ULg et al

in Journal of Dairy Science (2009), 92 - E-Suppl 1

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See detailEstimates of the annual net carbon and water exchange of forests: the EUROFLUX methodology.
Aubinet, Marc ULg; Grelle, A.; Ibrom, A. et al

in Advances in Ecological Research (1999), 30

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See detailEstimateurs Robustes pour les Composantes Principales
Croux, Christophe ULg; Haesbroeck, Gentiane ULg

in Proceedings des XXXII Journées de Statistique (2000)

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See detailEstimating abundances of retroviral insertion sites from DNA fragment length data.
Berry, Charles C.; Gillet, Nicolas ULg; Melamed, Anat et al

in Bioinformatics (Oxford, England) (2012), 28(6), 755-62

MOTIVATION: The relative abundance of retroviral insertions in a host genome is important in understanding the persistence and pathogenesis of both natural retroviral infections and retroviral gene ... [more ▼]

MOTIVATION: The relative abundance of retroviral insertions in a host genome is important in understanding the persistence and pathogenesis of both natural retroviral infections and retroviral gene therapy vectors. It could be estimated from a sample of cells if only the host genomic sites of retroviral insertions could be directly counted. When host genomic DNA is randomly broken via sonication and then amplified, amplicons of varying lengths are produced. The number of unique lengths of amplicons of an insertion site tends to increase according to its abundance, providing a basis for estimating relative abundance. However, as abundance increases amplicons of the same length arise by chance leading to a non-linear relation between the number of unique lengths and relative abundance. The difficulty in calibrating this relation is compounded by sample-specific variations in the relative frequencies of clones of each length. RESULTS: A likelihood function is proposed for the discrete lengths observed in each of a collection of insertion sites and is maximized with a hybrid expectation-maximization algorithm. Patient data illustrate the method and simulations show that relative abundance can be estimated with little bias, but that variation in highly abundant sites can be large. In replicated patient samples, variation exceeds what the model implies-requiring adjustment as in Efron (2004) or using jackknife standard errors. Consequently, it is advantageous to collect replicate samples to strengthen inferences about relative abundance. [less ▲]

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See detailEstimating afterload, systemic vascular resistance and pulmonary vascular resistance in an intensive care setting
Stevenson, D; Revie, J.; Chase, JG et al

in Proceedings of BMS2012 (2012)

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See detailEstimating age of admixture in a cattle population based on SNP chip data
Frkonja, A.; Druet, Tom ULg; Gredler, B. et al

in Acta Agriculturae Slovenica (2012), 100(SUPPL.3), 115-119

The aim of this study was to predict individual age of admixture in the crossbred Swiss Fleckvieh population. We checked how well the method is dealing with recent admixture with high throughput single ... [more ▼]

The aim of this study was to predict individual age of admixture in the crossbred Swiss Fleckvieh population. We checked how well the method is dealing with recent admixture with high throughput single nucleotide polymorphism data from the bovine 50K SNP Chip. A total of 101 Red Holstein, 91 Simmental, and 308 crossed animals were available for analysis. Age of admixture was derived from the complete pedigree and molecular markers. The method applied (using SABER software) based on Markov-hidden Markov model was able to derive age of admixture similar to estimates of pedigree data, however the values were often overestimated. Of 21 investigated cases, results from SNP data reflected paternal and maternal age of admixture well for 9 cases but provided results out of range for the other 12 cases. Alternative methods based on breed-specific haplotype blocks need to be evaluated in the future. [less ▲]

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See detailEstimating Antarctic ice sheet surface mass balance contribution to future sea level rise using the regional atmospheric climate model MAR
Agosta, Cécile ULg; Fettweis, Xavier ULg; Gallée, Hubert

Conference (2014, May 26)

The Antarctic ice-sheet surface mass balance (SMB) is a significant contribution to sea level changes which may mitigate the rise in sea level in a warmer climate, but this term is still poorly known. The ... [more ▼]

The Antarctic ice-sheet surface mass balance (SMB) is a significant contribution to sea level changes which may mitigate the rise in sea level in a warmer climate, but this term is still poorly known. The Antarctic SMB cannot be directly deduced from global climate models (GCMs) because of their too low resolution (~100 km) and their unadapted physic over cold and snow-covered areas. That is why the use of a regional climate models (RCM) specifically developed for polar regions is particularly relevant. We present here new estimations of the Antarctic SMB changes for the 20th and the 21st century at 40 km of resolution with the MAR (Modèle Atmosphérique Régional) RCM. Recent studies showed that large scale forcing from GCMs was the main source of uncertainty for RCM-deduced SMB, thus we first present a carefully analysis of the CMIP5 GCMs (used in the AR5 IPCC report) compared to the ERA-Interim reanalysis over the Antarctic region, from which we could select the less biased large scale forcing for MAR. We thus show the Antarctic SMB evolution as modeled with MAR forced by ACCESS1-3 for RCP 4.5 and 8.5 greenhouse gaz scenarios. We evaluate our outputs by comparing MAR forced by ACCESS1-3 and ERA-Interim for the 1980-2000 period to more than 2700 quality-controlled observations and to surface meteorological data from the READER database. We then give SMB changes estimations for the 21st century together with an analysis of uncertainties coming from the MAR model, the GCM forcing and the greenhouse gaz scenarios. [less ▲]

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See detailEstimating Antarctic ice sheet surface mass balance contribution to future sea level rise using the regional atmospheric climate model MAR
Agosta, Cécile ULg; Fettweis, Xavier ULg; Gallée, Hubert

Poster (2013, April)

We report future projections of Surface Mass Balance (SMB) over the Antarctic ice sheet obtained with the regional climate model MAR, for different warming scenarios. MAR forcing is carefully selected ... [more ▼]

We report future projections of Surface Mass Balance (SMB) over the Antarctic ice sheet obtained with the regional climate model MAR, for different warming scenarios. MAR forcing is carefully selected among the CMIP5 GCMs panel according to its ability to simulate the current climate over Antarctica. MAR includes blowing snow modeling, an important process in Antarctica. [less ▲]

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See detailEstimating CO2 flux of croplands for bottom-up carbon budgetting
Moureaux, Christine ULg; Aubinet, Marc ULg; Pattey, E. et al

in Geophysical Research Abstracts (2005), 7(1),

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See detailEstimating crop-specific evapotranspiration using remote-sensing imagery at various spatial resolutions for improving crop growth modelling
Sepulcre-Cantó, Guadalupe; Gellens-Meulenberghs, Françoise; Arboleda, Alirio et al

in International Journal of Remote Sensing (2013)

By governing water transfer between vegetation and atmosphere, evapotranspiration (ET) can have a strong influence on crop yields. An estimation of ET from remote sensing is proposed by the EUMETSAT ... [more ▼]

By governing water transfer between vegetation and atmosphere, evapotranspiration (ET) can have a strong influence on crop yields. An estimation of ET from remote sensing is proposed by the EUMETSAT ‘Satellite Application Facility’ (SAF) on Land Surface Analysis (LSA). This ET product is obtained operationally every 30 min using a simplified SVAT scheme that uses, as input, a combination of remotely sensed data and atmospheric model outputs. The standard operational mode uses other LSA-SAF products coming from SEVIRI imagery (the albedo, the downwelling surface shortwave flux, and the downwelling surface longwave flux), meteorological data, and the ECOCLIMAP database to identify and characterize the land cover. With the overall objective of adapting this ET product to crop growth monitoring necessities, this study focused first on improving the ET product by integrating crop-specific information from high and medium spatial resolution remote-sensing data. A Landsat (30 m)-based crop type classification is used to identify areas where the target crop, winter wheat, is located and where crop-specific Moderate Resolution Imaging Spectroradiometer (MODIS) (250 m) time series of green area index (GAI) can be extracted. The SVAT model was run for 1 year (2007) over a study area covering Belgium and part of France using this supplementary information. Results were compared to those obtained using the standard operational mode. ET results were also compared with ground truth data measured in an eddy covariance station. Furthermore, transpiration and potential transpiration maps were retrieved and compared with those produced using the Crop Growth Monitoring System (CGMS), which is run operationally by the European Commission’s Joint Research Centre to produce in-season forecast of major European crops. The potential of using ET obtained from remote sensing to improve crop growth modelling in such a framework is studied and discussed. Finally, the use of the ET product is also explored by integrating it in a simpler modelling approach based on light-use efficiency. The Carnegie–Ames–Stanford Approach (CASA) agroecosystem model was therefore applied to obtain net primary production, dry matter productivity, and crop yield using only LSA-SAF products. The values of yield were compared with those obtained using CGMS, and the dry matter productivity values with those produced at the Flemish Institute for Technological Research (VITO). Results showed the potential of using this simplified remote-sensing method for crop monitoring. [less ▲]

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See detailEstimating daily yield and content of major fatty acids from single milking
Arnould, Valérie ULg; Reding, Romain; Delvaux, Charles et al

Poster (2014, February 07)

Reducing the frequency of milk recording and the number of recorded samples per test-day could be a solution in order to reduce costs of official milk recording. However, fewer samples lead to a decrease ... [more ▼]

Reducing the frequency of milk recording and the number of recorded samples per test-day could be a solution in order to reduce costs of official milk recording. However, fewer samples lead to a decrease in the accuracy of predicted daily yields. Unfortunately, the current published equations use the milking interval that is often not available and/or reliable in practice. The first objective of this study was to propose models using easily available traits. Therefore the milking interval was replaced by a combination of data easily recorded by milk recording. The second objective of this study was to enlarge the previous investigations to milk fatty acids (FA) in order to propose a practical method for estimating accurate daily milk, fat and major FA yields from single milking. The fit goodness of proposed models was evaluated based on the correlation values between the estimated and observed daily yields in addition to the calculation of the mean square error. Obtained results are promising. Correlation values were comprised between 96.4% and 97.6% when daily yield were estimated from morning milking, and from 96.9% to 98.3% when daily yield were estimated from evening milking. The combination of records related to lactation stage, month of test, milk yield, and fat could replace the milking interval effect. Because of their simplicity, proposed models would be easy to implement. [less ▲]

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See detailEstimating daily yield and content of major fatty acids from single milking: First approach
Arnould, Valérie ULg; Froidmont, Eric; Nguyen, Nam et al

Poster (2011, July 11)

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See detailEstimating daily yield of major fatty acids from single milking: first approach.
Arnould, Valérie ULg; NGuyen, N. H.; Froidmont et al

in Journal of Dairy Science (2011, July), 94(E-Suppl. 1), 29

Reducing the frequency of milk recording and the number of recorded samples per test-day could be a solution in order to reduce costs of milk recording. However, this solution leads to decrease also the ... [more ▼]

Reducing the frequency of milk recording and the number of recorded samples per test-day could be a solution in order to reduce costs of milk recording. However, this solution leads to decrease also the accuracy of predicting daily yield. According to the literature, several authors have already worked on this problematic. Unfortunately, some effects used in previous studies are not often available or reliable in used databases. This study was aimed to enlarge these investigations to milk fatty acids (FA) production: saturated FA, mono-unsaturated FA, unsaturated FA, medium-chain FA, and long chain FA and to propose a simple, robust and practical method for estimating accurate daily major FA yield from single milking. To do this, five dairy cows were followed between January 2007 and December 2010. FA contents were predicted by mid-infrared spectrometry. The final database contained 1,440 records. The first step was to ensure that used effects were available in most used databases. According to the availability of data, height models were tested to estimate daily yields from both morning and evening milking. These models were compared on the basis of the coefficient of determination values between estimated and observed daily yields and the mean square error. The proposed models included progressively several effects such as the milk yield, the fat and protein content, some classes of stage in lactation, of month of test or of month of calving. As expected, R² values were higher when these effects are introduced in the model and were comprised between 0.87 and 0.88 when daily yield were estimated from morning milking, and from 0.75 and 0.86 when daily yield were estimated from evening milking. It was concluded that the introduction of these effects did highly improve the daily predictability of all trait yield and can partially replace the milking interval effect. It was also observed that daily yields estimated from evening milkings are less accurate than those estimated from morning milkings. Finally, the applied model will depend on the availability of the data and to the convenience of the applied model to the studied population. Keywords: Milk recording, Fatty acids, prediction [less ▲]

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