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See detailRestauration écologique: contexte, contraintes et indicateurs de suivi
Cristofoli, Sara ULg; Mahy, Grégory ULg

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2010), 14(1), 203-211

Dans un contexte global de perturbations anthropiques toujours croissantes des écosystèmes naturels et semi-naturels, l’unique conservation de ces écosystèmes ne suffit plus. La restauration écologique ... [more ▼]

Dans un contexte global de perturbations anthropiques toujours croissantes des écosystèmes naturels et semi-naturels, l’unique conservation de ces écosystèmes ne suffit plus. La restauration écologique peut ainsi se révéler un complément essentiel à la conservation s.l. L’article consiste en une synthèse de la littérature scientifique dédiée aux concepts de la restauration écologique. Nous abordons la notion d’objectifs de la restauration notamment au travers de la référence écologique. Outre la définition d’objectifs clairs de restauration, la référence permet ensuite d’évaluer les efforts de restauration, par le biais d’indicateurs de suivi. Les indicateurs peuvent par ailleurs fournir des informations quant aux attributs de l’écosystème restauré et/ou la trajectoire écologique empruntée. Les éventuelles contraintes rencontrées par les espèces au travers de filtres à la restauration pourront être détectées et des mesures de compensation adéquates pourront être proposées. [less ▲]

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See detailUsefulness of cardiac resynchronisation therapy in patients with right bundle branch block: is viability an important piece of the puzzle?
O'Connor, K.; Sénéchal, M.; Lancellotti, Patrizio ULg et al

in International Journal of Cardiology (2010), 145(1), 17-20

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See detailThe stratigraphical architecture of the Quaternary deposits as support for hydrogeological modelling of the central zone of Hanoi (Vietnam)
Jusseret, Simon; Baeteman, Cecile; Dassargues, Alain ULg

in Geologica Belgica (2010), 13(1-2), 77-90

The Quaternary deposits of the Hanoi area have been investigated in order to provide information required for the design of a groundwater-flow model. Limited sedimentological data exist from 32 ... [more ▼]

The Quaternary deposits of the Hanoi area have been investigated in order to provide information required for the design of a groundwater-flow model. Limited sedimentological data exist from 32 destructive drillings carried out previously in the study area. The data base contains hydrographical and hydrogeological observations, but few sedimentological details. This is in contrast with the more seaward regions of the area where the Holocene deposits of the Red River plain has previously been studied. However, a comparison of the results obtained in this study with the previous studies indicates that the Hanoi sediment succession developed in an incised valley under conditions of rapid relative sealevel rise until ca. 7-6 a cal BP. The succession consists initially of alluvial floodplain deposits conformably overlain by mud deposited at the head of an estuary which filled with continuing rapid sea-level rise. Once the relative sea-level rise stabilized, fluvial deposition prograded over the adjacent estuarine mud. The development of a groundwater-flow model requires knowledge of the three-dimensional distribution of the various deposits. Despite the paucity of information with respect to sediment description, a model of the entire Quaternary sequence is presented in several lithostratigraphic crosssections and a panel diagram. The latter forms the basis for the construction of a contour map of the base of the Pleistocene and Holocene deposits, and for a sequence map of the Quaternary deposits in the study area. [less ▲]

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See detailA magnetic susceptibility curve for the Devonian Limestone from Belgium
Boulvain, Frédéric ULg; Mabille, Cédric ULg; Poulain, Geoffrey et al

in Geologica Belgica (2010), 13

This paper proposes a first magnetic susceptibility (MS) curve for the Devonian Limestone from Belgium. A comparison with a large scale depositional model shows the complex relations between MS and ... [more ▼]

This paper proposes a first magnetic susceptibility (MS) curve for the Devonian Limestone from Belgium. A comparison with a large scale depositional model shows the complex relations between MS and paleoenvironments. Other Devonian-scale MS curves from other parts of the world are necessary to constraint these relations. [less ▲]

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See detailCarbonate chemistry in the coastal zone responds more strongly to eutrophication than to ocean acidification
Borges, Alberto ULg; Gypens, N.

in Limnology & Oceanography (2010), 55(1), 346-353

The accumulation of anthropogenic CO2 in the ocean has altered carbonate chemistry in surface waters since preindustrial times and is expected to continue to do so in the coming centuries. Changes in ... [more ▼]

The accumulation of anthropogenic CO2 in the ocean has altered carbonate chemistry in surface waters since preindustrial times and is expected to continue to do so in the coming centuries. Changes in carbonate chemistry can modify the rates and fates of marine primary production and calcification. These modifications can in turn lead to feedback on increasing atmospheric CO2. We show, using a numerical model, that in highly productive nearshore coastal marine environments, the effect of eutrophication on carbon cycling can counter the effect of ocean acidification on the carbonate chemistry of surface waters. Also, changes in river nutrient delivery due to management regulation policies can lead to stronger changes in carbonate chemistry than ocean acidification. Whether antagonistic or synergistic, the response of carbonate chemistry to changes of nutrient delivery to the coastal zone (increase or decrease, respectively) is stronger than ocean acidification. [less ▲]

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See detailGrégoire Polet. La complexité du monde
Robert, Laurent ULg

Article for general public (2010)

L'article présente l'oeuvre du romancier belge Grégoire Polet, dans une perspective de découverte d'un auteur encore en devenir.

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See detailColoss Working Group 1: monitoring and diagnosis.
Nguyen, Bach Kim ULg; Van der zee, Romée; Vejsnaes, Flemming et al

in Journal of Apicultural Research (2010), 49(1), 97-99

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See detailAssessment of conceptual model uncertainty for the regional aquifer Pampa del Tamarugal – North Chile
Rojas, Rodrigo; Batelaan, Okke; Feyen, Luk et al

in Hydrology and Earth System Sciences (2010), 14

In this work we assess the uncertainty in modelling the groundwater flow for the Pampa del Tamarugal Aquifer (PTA) – North Chile using a novel and fully integrated multimodel approach aimed at explicitly ... [more ▼]

In this work we assess the uncertainty in modelling the groundwater flow for the Pampa del Tamarugal Aquifer (PTA) – North Chile using a novel and fully integrated multimodel approach aimed at explicitly accounting for uncertainties arising from the definition of alternative conceptual models. The approach integrates the Generalized Likelihood Uncertainty Estimation (GLUE) and Bayesian Model Averaging (BMA) methods. For each member of an ensemble M of potential conceptualizations, model weights used in BMA for multi-model aggregation are obtained from GLUE-based likelihood values. These model weights are based on model performance, thus, reflecting how well a conceptualization reproduces an observed dataset D. GLUE-based cumulative predictive distributions for each member of M are then aggregated obtaining predictive distributions accounting for conceptual model uncertainties. For the PTA we propose an ensemble of eight alternative conceptualizations covering all major features of groundwater flow models independently developed in past studies and including two recharge mechanisms which have been source of debate for several years. Results showed that accounting for heterogeneities in the hydraulic conductivity field (a) reduced the uncertainty in the estimations of parameters and state variables, and (b) increased the corresponding model weights used for multi-model aggregation. This was more noticeable when the hydraulic conductivity field was conditioned on available hydraulic conductivity measurements. Contribution of conceptual model uncertainty to the predictive uncertainty varied between 6% and 64% for ground water head estimations and between 16% and 79% for ground water flow estimations. These results clearly illustrate the relevance of conceptual model uncertainty. [less ▲]

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See detailIncidence of sport injuries in elite young athletes of the Grand-duchy of Luxembourg
Frisch, Anne ULg; Urhausen, A.; Seil et al

in Buys, R.; Buerkers, M.; Daly, D. (Eds.) Programma boek final of the 12th International ACAPS Conference (2010)

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See detailSecuring Transient Stability using Time-Domain Simulations within an Optimal Power Flow
Zarate-Minano, Rafael; Van Cutsem, Thierry ULg; Milano, Federico et al

in IEEE Transactions on Power Systems (2010), 25(1), 243-253

This paper provides a methodology to restore transient stability. It relies on a well-behaved optimal power flow model with embedded transient stability constraints. The proposed methodology can be used ... [more ▼]

This paper provides a methodology to restore transient stability. It relies on a well-behaved optimal power flow model with embedded transient stability constraints. The proposed methodology can be used for both dispatching and redispatching. In addition to power flow constraints and limits, the resulting optimal power flow model includes discrete time equations describing the time evolution of all machines in the system. Transient stability constraints are formulated by reducing the initial multi-machine model to a one-machine infinite-bus equivalent. This equivalent allows imposing angle bounds that ensure transient stability. The proposed optimal power flow model is tested and analyzed using an illustrative 9-bus system, the well-known New England 39-bus, 10-machine system and a real-world 1228-bus system with 292 synchronous machines. [less ▲]

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See detailUse of ISSR markers to assess genetic diversity of African edible seeded Citrullus lanatus landraces
Dje, Yao; Tahi, C. G.; Zoro Bi, A. I. et al

in Scientia Horticulturae (2010), 124

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See detailLong-term trend of carbon tetrachloride (CCl4) from ground-based high resolution infrared solar spectra recorded at the Jungfraujoch
Rinsland, Curtis P.; Mahieu, Emmanuel ULg; Demoulin, Philippe ULg et al

in Geophysical Research Abstracts (2010), 12(EGU2010-1819-3),

The long-term trend of carbon tetrachloride (CCl4) has been retrieved from infrared high resolution solar absorption spectra encompassing the 1999 to 2010 time period. The measurements were recorded with ... [more ▼]

The long-term trend of carbon tetrachloride (CCl4) has been retrieved from infrared high resolution solar absorption spectra encompassing the 1999 to 2010 time period. The measurements were recorded with a Fourier transform spectrometer at the northern mid-latitude, high altitude Jungfraujoch station in Switzerland (46.5°N latitude, 8.0°E longitude, 3580 m altitude). Total columns were derived from the region of the strong CCl4 _3 band at 794 cm􀀀1 accounting for all interfering molecules (e.g. H2O, O3) with significant improvement in the residuals obtained by also taking into account the line mixing in a nearby CO2 Q branch, a procedure not implemented in previous remote sensing CCl4 retrievals though its importance has been noted in several papers. The time series shows a statistically-significant long-term decrease in the CCl4 total atmospheric burden of -1.18_0.10 %/yr, at the 95% confidence level, using 2005 as reference. Furthermore, fit to the total column data set also reveals a seasonal cycle with a peak-to-peak amplitude of 10.2%, with minimum and maximum values found in mid-February and early August, respectively. This seasonal modulation can however be attributed to tropopause height changes throughout the season. The results quantify the continued impact of the regulations implemented by the Montreal Protocol and its strengthening amendments and adjustments for a molecule with high global warming potential. Although a statistically significant decrease in the total column is inferred, the CCl4 molecule remains an important contributor to the stratospheric chlorine budget and burden. [less ▲]

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See detailTrends of CO2, CH4 and N2O over 1985-2010 from high-resolution FTIR solar observations at the Jungfraujoch station
Duchatelet, Pierre ULg; Mahieu, Emmanuel ULg; Zander, Rodolphe ULg et al

in Geophysical Research Abstracts (2010), 12(EGU2010-15418-2),

Two state-of-the-art Fourier Transform Infrared (FTIR) spectrometers are operated at the Jungfraujoch station (46.5ºN, 8.0ºE, 3580m asl) within the framework of the Network for the Detection of ... [more ▼]

Two state-of-the-art Fourier Transform Infrared (FTIR) spectrometers are operated at the Jungfraujoch station (46.5ºN, 8.0ºE, 3580m asl) within the framework of the Network for the Detection of Atmospheric Composition Change (NDACC, visit http://www.ndacc.org). The earliest FTIR observations have been obtained there in 1984. Since then, regular recordings of high-resolution solar absorption spectra have been performed at that site, under clear-sky conditions, allowing to collect almost 29000 observations relevant to the present communication. We present time series of three greenhouse gases targeted by the Kyoto Protocol: CO2, CH4 (and its isotopologue 13CH4) and N2O. These data sets have been obtained with the SFIT-2 algorithm which implements the Optimal Estimation Method of Rodgers (1990). This allows retrieving total columns of the target gases as well as information on their distribution with altitude. For the methane isotopologues and N2O, a Tikhonov L1 regularization scheme has been applied, as part of an harmonization effort carried out within the European HYMN project (see also Dils et al, 2010; Foster et al., 2010). Trends –and their associated uncertainties– characterizing these long series as well as the seasonal modulations have been determined with a statistical tool using bootstrap resampling (Gardiner et al., 2008). Trend values will be presented and critically discussed; in particular, we will investigate if significant changes in the rate of accumulations of these four atmospheric gases occurred over the last 25 years. Numerous additional greenhouse gases are accessible to the FTIR technique. Examples of such trend studies are reported at the EGU General Assembly by Mahieu et al. (2010) and Rinsland et al. (2010). [less ▲]

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See detailDamage Diagnosis of Beam-like Structures Based on Sensitivities of Principal Component Analysis Results
Nguyen, Viet Ha ULg; Golinval, Jean-Claude ULg

in IMAC-XXVIII A Conference on Structural Dynamics (2010)

This paper addresses the problem of damage detection and localization in linear-form structures. Principal Component Analysis (PCA) is a popular technique for dynamic system investigation. The aim of the ... [more ▼]

This paper addresses the problem of damage detection and localization in linear-form structures. Principal Component Analysis (PCA) is a popular technique for dynamic system investigation. The aim of the paper is to present a damage diagnosis method based on sensitivities of PCA results in the frequency domain. Starting from Frequency Response Functions (FRFs) measured at different locations on the beam, PCA is performed to determine the main features of the signals. Sensitivities of principal directions obtained from PCA to beam parameters are then computed and inspected according to the location of sensors; their variation from the healthy state to the damaged state indicates damage locations. It is worth noting that damage localization is performed without the need of modal identification. Once the damage has been localized, its evaluation may be quantified if a structural model is available. This evaluation is based on a model updating procedure using previously estimated sensitivities. The efficiency and limitations of the proposed method are illustrated using numerical and experimental examples. [less ▲]

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See detailLe langage spontané des enfants prématurissimes : analyse du langage descriptif et informatif
Grooteclaes, Vanessa; Docquier, Laurence ULg; Maillart, Christelle ULg

in Glossa (2010), 108

The limits of prematurity don’t stop moving back and very premature children with a very low birth weight survive. Since a short time studies have been conducted on the cognitive and language evolution of ... [more ▼]

The limits of prematurity don’t stop moving back and very premature children with a very low birth weight survive. Since a short time studies have been conducted on the cognitive and language evolution of those children. This present study aims to determine the nature of language repercussions of extremely prematurity birth by focusing more particularly on spontaneous language. Language performances of 23 children born at less than 26 weeks of gestational age will be compared to the ones of 23 children born at term, paired by age (between 6 and 8 years old), sex and sociocultural level. Two tasks will be compared : a task of descriptive language (narration based on pictures) and a test of informative language in which the child will have to transmit some precise information on the realization of familiar actions. The children’s productions have been written down, then analysed from a lexical, syntactic and semantic point of view. Results show that the two groups of children do not differ in the task of descriptive language but differences emerge in the task of informative language. On lexical level the richness and variety of words used by premature children seem poorer than the ones used by children born at term. From the syntactic point of view the average length of utterances of premature children is inferior to the one of children born at term. At last the semantic analyses show that the premature children express less ideas and that the semantic content of the given ideas is less rich in comparison with the children born at term. In conclusion this study suggests that the discursive level of highly premature children mustn’t only be tested with descriptive tasks but also with informative tasks which seem more sensible to the specific weaknesses of that population. [less ▲]

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See detailMise en relation de l'évolution de l'agriculture et de la qualité de l'eau entre 1950 et 2000
Vandenberghe, Christophe ULg

in Vandenberghe, Christophe; Marcoen, Jean Marie (Eds.) Atelier "Nitrate - Eau". 2 au 5 juin 2009. Peyresq, France (2010)

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See detailEvaluation de l'efficacité des cultures intermédiaires pièges à nitrate (CIPAN) en novembre
Vandenberghe, Christophe ULg; Lambert, Richard; Marcoen, Jean Marie ULg

in Vandenberghe, Christophe; Marcoen, Jean Marie (Eds.) Actes de l'Atelier "Nitrate - Eau" 2 au 5 juin 2009. Peyresq, France (2010)

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See detailSpatiotemporal variations of fCO(2) in the North Sea
Omar, A. M.; Olsen, A.; Johannessen, T. et al

in Ocean Science (2010), 6(1), 77-89

Data from two Voluntary Observing Ship (VOS) (2005-2007) augmented with data subsets from ten cruises (1987-2005) were used to investigate the spatiotemporal variations of the CO2 fugacity in seawater ... [more ▼]

Data from two Voluntary Observing Ship (VOS) (2005-2007) augmented with data subsets from ten cruises (1987-2005) were used to investigate the spatiotemporal variations of the CO2 fugacity in seawater (fCO(2)(sw)) in the North Sea at seasonal and inter-annual time scales. The observed seasonal fCO(2)(sw) variations were related to variations in sea surface temperature (SST), biology plus mixing, and air-sea CO2 exchange. Over the study period, the seasonal amplitude in fCO(2)(sw) induced by SST changes was 0.4-0.75 times those resulting from variations in biology plus mixing. Along a meridional transect, fCO(2)(sw) normally decreased northwards (-12 mu atm per degree latitude), but the gradient disappeared/reversed during spring as a consequence of an enhanced seasonal amplitude of fCO(2)(sw) in southern parts of the North Sea. Along a zonal transect, a weak gradient (-0.8 mu atm per degree longitude) was observed in the annual mean fCO(2)(sw). Annually and averaged over the study area, surface waters of the North Sea were CO2 undersaturated and, thus, a sink of atmospheric CO2. However, during summer, surface waters in the region 55.5-54.5 degrees N were CO2 supersaturated and, hence, a source for atmospheric CO2. Comparison of fCO(2)(sw) data acquired within two 1 degrees x1 degrees regions in the northern and southern North Sea during different years (1987, 2001, 2002, and 2005-2007) revealed large interannual variations, especially during spring and summer when year-to-year fCO(2)(sw) differences (approximate to 160-200 mu atm) approached seasonal changes (approximate to 200-250 mu atm). The springtime variations resulted from changes in magnitude and timing of the phytoplankton bloom, whereas changes in SST, wind speed and total alkalinity may have contributed to the summertime interannual fCO(2)(sw) differences. The lowest interannual variation (10-50 mu atm) was observed during fall and early winter. Comparison with data reported in October 1967 suggests that the fCO(2)(sw) growth rate in the central North Sea was similar to that in the atmosphere. [less ▲]

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See detailConceptual model of integrated apiarian consultancy
Bodescu, Dan; Stefan, Gavril; Paveliuc Olariu, Codrin ULg et al

in Scientific Papers. Series Management, Economic, Engineering in Agriculture and Rural Development (2010), 10(3), 47-51

The socio-economic field researches have indicated the necessity of realizing an integrated consultancy service for beekeepers that will supply technical-economic solutions with a practical character for ... [more ▼]

The socio-economic field researches have indicated the necessity of realizing an integrated consultancy service for beekeepers that will supply technical-economic solutions with a practical character for ensuring the lucrativeness and viability of the apiaries. Consequently, an integrated apiarian consultancy model has been built holding the following features: it realizes the diagnosis of the meliferous resources and supplies solutions for its optimal administration; it realizes the technical-economic of the apiarian exploitation adapted according to its objectives and identifies its optimal administration measures; it manages the local pollination services market; it realizes viable investment projects and ensures the management of their implementation; it elaborates aggregated indicators as efficient instruments of analysis and utilizes and informatics application of apiarian management used for realizing the specific objectives of the apiaries; it integrates the technical, economic and juridical consultancy service. [less ▲]

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See detailPrevalence and sources of Campylobacter spp. contamination in free-range broiler production in the southern part of Belgium
Vandeplas, Sabrina ULg; Dubois Dauphin, Robin ULg; Palm, Rodolphe ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2010), 14(2), 279-288

A one year epidemiological study was carried out between February 2005 and January 2006 in the southern part of Belgium to assess the Campylobacter prevalence in free-range broiler production. Three ... [more ▼]

A one year epidemiological study was carried out between February 2005 and January 2006 in the southern part of Belgium to assess the Campylobacter prevalence in free-range broiler production. Three successive broiler flocks from six Belgian farms were investigated for the presence of Campylobacter spp. during the rearing period. Each flock was visited four times, before and after the outdoor rearing period. During each visit, samples were taken in the broiler house (litter, cecal droppings, water-lines, feed, anteroom) as well as from the outer rearing environment (open-air range). The Campylobacter detection in all samples was carried out according to the ISO 10272 standard. Identification was based on colonial morphology, microscopic examination, and biochemical tests. PCR multiplex was used for genetic confirmation. Campylobacter jejuni was the main species isolated from all contaminated samples. Overall, mixed infections C. jejuni/C. coli represented 40.6%, while C. jejuni and C. coli represented 46.9% and 12.5% of chicken samples respectively. A 100% flock contamination was observed in the 6 farms during the summer/autumn period, whereas only 66.7% and 33.3% of the flocks became Campylobacter-positive in spring and winter respectively, at the end of the rearing period. Half of contaminated flocks were infected before chickens have access to the open-air range. Environmental samples, especially the open-air range soil, were found to be Campylobacter-positive before flock infection. The other potential sources of contamination were delivery tray, anteroom floor and water-lines. Other animal productions like cattle on the farm, no applied rodent control, no cleaning and disinfection of water-lines between flocks, no detergent used for cleansing and thinning were recorded as risk factors. In conclusion, the contact with the environment, particularly the access to an open-air range, appeared to be the major way of Campylobacter contamination of chickens in free-range broiler production. [less ▲]

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