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See detailAssessing and aggregating trends in groundwater bodies. Examples of the FP VI Aquaterra-project
Broers, Hans-peter; Visser, Ate; Brouyère, Serge ULg et al

in EU Groundwater Policy Development - Good Status Objectives and Integrated management planning (2008, November)

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See detailAssessing and Harmonizing Lying Deadwood Volume with Regional Forest Inventory Data in Wallonia (Southern Region of Belgium)
Ligot, Gauthier ULg; Lejeune, Philippe ULg; Rondeux, Jacques ULg et al

in Open Forest Science Journal (2012), 5

Using lying deadwood or coarse woody debris (CWD) is on the rise among national and local forest inventories. We compared two generally recommended methods for lying deadwood: line intersect sampling and ... [more ▼]

Using lying deadwood or coarse woody debris (CWD) is on the rise among national and local forest inventories. We compared two generally recommended methods for lying deadwood: line intersect sampling and fixed area sampling. We assessed both methods in plots of the regional forest inventory of Wallonia (southern region of Belgium) and we developed bridging functions that converts CWD volume estimates to estimates that would have been obtained with different thresholds. [less ▲]

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See detailAssessing and modeling economic and environmental impact of wheat nitrogen management in Belgium
Dumont, Benjamin ULg; Basso, Bruno; Bodson, Bernard ULg et al

in Environmental Modelling & Software (2016), 79

Future progress in wheat yield will rely on identifying genotypes and management practices better adapted to the fluctuating environment. Nitrogen (N) fertilization is probably the most important practice ... [more ▼]

Future progress in wheat yield will rely on identifying genotypes and management practices better adapted to the fluctuating environment. Nitrogen (N) fertilization is probably the most important practice impacting crop growth. However, the adverse environmental impacts of inappropriate N management (e.g., lixiviation) must be considered in the decision-making process. A formal decisional algorithm was developed to tactically optimize the economic and environmental N fertilization in wheat. Climatic uncertainty analysis was performed using stochastic weather time-series (LARS-WG). Crop growth was simulated using STICS model. Experiments were conducted to support the algorithm recommendations: winter wheat was sown between 2008 and 2014 in a classic loamy soil of the Hesbaye Region, Belgium (temperate climate). Results indicated that, most of the time, the third N fertilization applied at flag-leaf stage by farmers could be reduced. Environmental decision criterion is most of the time the limiting factor in comparison to the revenues expected by farmers. [less ▲]

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See detailAssessing and modelling ecosystem changes in the Mediterranean and the Black Sea pelagic ecosystem - SESAME
Grégoire, Marilaure ULg; Ruiz, Javier; Ozsoy, Emin et al

Book published by Journal of Marine Systems, Elsevier Science, (135), 180p. (2014)

SESAME was an Integrated Project under the European Union's 6th Framework Programme. The project involved almost four hundred scientists from 59 research institutes in 24 countries, which included almost ... [more ▼]

SESAME was an Integrated Project under the European Union's 6th Framework Programme. The project involved almost four hundred scientists from 59 research institutes in 24 countries, which included almost all countries of the Mediterranean and Black Sea Basins. This level of cooperation and coordination allowed data collection on different aspects of the Mediterranean and Black Sea ecosystems on a scale never before attempted. The project was designed to study the past, present and future environmental changes in the Southern European Seas (SES) ecosystems, as well as the effect of these changes on fundamental goods (tourism, fisheries) and services (mitigation of climate through carbon sequestration and ecosystem stability through conservation of biodiversity) provided by the ecosystems. The project's innovative character was reflected in the close merging of economic and natural sciences to study changes that occurred in the past 50 years and those that may occur in the next 50 years, through connecting ecological models with climatic and socio-economic scenarios. [less ▲]

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See detailAssessing consciousness in coma and related states using transcranial magnetic stimulation combined with electroencephalography.
Gosseries, Olivia ULg; Thibaut, Aurore ULg; Boly, Mélanie ULg et al

in Annales Françaises d'Anesthésie et de Réanimation (2014)

Thanks to advances in medical care, an increased number of patients recover from coma. However, some remain in vegetative/unresponsive wakefulness syndrome or in a minimally conscious state. Detection of ... [more ▼]

Thanks to advances in medical care, an increased number of patients recover from coma. However, some remain in vegetative/unresponsive wakefulness syndrome or in a minimally conscious state. Detection of awareness in severely brain-injured patients is challenging because it relies on behavioral assessments, which can be affected by motor, sensory and cognitive impairments of the patients. Other means of evaluation are needed to improve the accuracy of the diagnosis in this challenging population. We will here review the different altered states of consciousness occurring after severe brain damage, and explain the difficulties associated with behavioral assessment of consciousness. We will then describe a non-invasive technique, transcranial magnetic stimulation combined with high-density electroencephalography (TMS-EEG), which has allowed us to detect the presence or absence of consciousness in different physiological, pathological and pharmacological states. Some potential underlying mechanisms of the loss of consciousness will then be discussed. In conclusion, TMS-EEG is highly promising in identifying markers of consciousness at the individual level and might be of great value for clinicians in the assessment of consciousness. [less ▲]

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See detailAssessing deadwood using harmonized National Forest Inventory data
Rondeux, Jacques ULg; Bertini, Roberta; Bastrup-Birk, Annemarie et al

in Forest Science (2012), 58(3), 269-283

Deadwood plays an important role in forest ecological processes and is fundamental for the maintenance of biological diversity. Further, it is a forest carbon pool whose assessment must be reported for ... [more ▼]

Deadwood plays an important role in forest ecological processes and is fundamental for the maintenance of biological diversity. Further, it is a forest carbon pool whose assessment must be reported for international agreements dealing with protection and forest management sustainability. Despite wide agreement on deadwood monitoring by national forest inventories (NFIs), much work is still necessary to clarify definitions so that estimates can be directly compared or aggregated for international reporting. There is an urgent need for an international consensus on definitions and agreement on harmonization methods. The study addresses two main objectives : to analyze the feasibility of harmonization procedures for deadwood estimates and to evaluate the impact of the harmonization process based on different definitions on final deadwood estimates. Results are reported for an experimental harmonization test using NFI deadwood data from 9,208 sample plots measured in nine European countries and the United States. Harmonization methods were investigated for volume by spatial position (lying or standing), decay classes, and woody species accompanied by accuracy assessments. Estimates of mean plot volume based on harmonized definitions with minimum length/height of 1 m and minimum diameter thresholds of 10, 12, and 20 cm were on average 3, 8, and 30% smaller, respectively, than estimates based on national definitions. Volumedifferences were less when estimated for various deadwood categories. An accuracy assessment demonstrated that, on average, the harmonization procedures did not substantially alter deadwood observations (root mean square error 23.17%). [less ▲]

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See detailAssessing donor chimerism level among CD3 T, CD4 T, CD8 T, and NK cells predicts subsequent graft rejection, GVHD, and relapse after allogeneic HCT with nonmyeloablative conditioning
Baron, Frédéric ULg; Storb, R.; Gooley, T. et al

in Biology of Blood & Marrow Transplantation (2005), 11(2), 11

We previously showed that low levels of day-14 CD3 T and NK (CD56) cells donor chimerism predicted graft rejection, whereas high levels of day-28 CD3 T-cell donor chimerism predicted acute graft-versus ... [more ▼]

We previously showed that low levels of day-14 CD3 T and NK (CD56) cells donor chimerism predicted graft rejection, whereas high levels of day-28 CD3 T-cell donor chimerism predicted acute graft-versus-host disease (GVHD) after HCT with nonmyeloablative conditioning. Here we investigate whether assessing chimerism levels among CD4 T cells and CD8 T cells, and also the absolute number of lymphocyte subsets of donor and host origins, would lend greater precision to our initial observations. We analyzed data from 157 patients receiving HCT after conditioning with 2 Gy TBI +/− fludarabine as treatment for AML (n= 22), ALL (n= 4), CML (n= 13), CLL (n= 19), MDS (n= 26), MM (n= 24), NHL (n= 30), HD (n= 14), RCC (n= 4), and WASP deficiency (n= 1). Postgrafting immunosuppression included MMF and CSP. A total of 97 patients received grafts from HLA-identical siblings, and 60 patients received grafts from HLA-matched unrelated donors. Lymphocyte subsets were isolated from peripheral blood by flow cytometry on days 14, 28, and 42. The proportion of cells of donor origin (chimerism levels) were assessed by VNTR-PCR and quantified by phosphor imaging. Eighteen patients (11%) had graft rejection. Day-14 donor chimerism levels< 50% among CD3 T (P =.0007), CD4 T (P =.03), and NK cells (P =.003) but not CD8 T cells predicted graft rejection. High absolute numbers of CD3 T (P =.002) and NK cells (P= .002) of host origin on day 14 were each associated with increased risks of graft rejection when treated as continuous linear variables. Grades 2, 3, and 4 acute GVHD were seen in 40%, 9%, and 5% of patients, respectively. High donor chimerism levels on day 14 among CD3 T (P= .02), CD4 T (P =.03), and CD8 T cells (P =.02) but not NK cells were each associated with increased risks of grades 2–4 acute GVHD. High absolute numbers of CD4 T (P =.04) and CD8 T cells (P =.04) of donor origin on days 14–42 were each associated with increased risks of grade 2–4 acute GVHD when treated as continuous linear variables, whereas high donor CD3 T (P= .002), CD8 T (P= .006), and NK cell (P= .002) chimerism levels from days 14–42 were associated with decreased risks of relapse. No statistically significant correlations between absolute numbers of donor cells and risks of relapse were found. These data suggest that assessing CD3, CD4, CD8, and NK cell donor chimerism levels and determining absolute numbers of CD3 and NK cells of host and donor origins are useful for predicting HCT outcomes after nonmyeloablative conditioning. [less ▲]

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See detailAssessing dynamical correlations between functional and structural brain connectivity
Liegeois, Raphaël ULg; Ziegler, Erik; Phillips, Christophe ULg et al

Poster (2014)

The link between resting­‐state functional connectivity (FC), measured by the correlations of the fMRI BOLD time courses, and structural connectivity (SC) has been repeatedly investigated recently ... [more ▼]

The link between resting­‐state functional connectivity (FC), measured by the correlations of the fMRI BOLD time courses, and structural connectivity (SC) has been repeatedly investigated recently. Meanwhile, the importance of considering the dynamics of neuronal processes has also been highlighted. In this work we show how the classical static (i.e. considered as constant) relationship between SC and FC could be enriched when the FC dynamics are taken into account. We use a sliding window approach to explore these dynamics and show that the window width should be chosen in a particular range in order to unveil statistically significant (i.e. not due to noise) fluctuations of the FC-­‐SC correlation. [less ▲]

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See detailAssessing ecosystem changes in the North Western shelf of the Black Sea using 3D coupled models
Capet, Arthur ULg; Beckers, Jean-Marie ULg; Joassin, Pascal et al

Conference (2009, November 11)

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See detailAssessing electrical resistivity tomography for hydrofacies detection using a sensitivity dependent probabilistic methodology
Hermans, Thomas ULg; Irving, James

in EarthDoc - Near Surface Geosciences 2015 (2015, September 08)

Alluvial aquifers are generally composed of several facies with complex architectures and interconnections depending on the fluvial system. In this context, electrical resistivity tomography (ERT) may ... [more ▼]

Alluvial aquifers are generally composed of several facies with complex architectures and interconnections depending on the fluvial system. In this context, electrical resistivity tomography (ERT) may provide important information on the spatial distribution of hydrogeological parameters. However, ERT inversion introduces some bias in the resulting resistivity distribution due to regularization and resolution issues. In this study, we refine ERT inversions by incorporating prior information in order to improve the identification of facies through a probabilistic relationship derived from collocated measurements. We then analyze with synthetic cases the effect of spatially varying sensitivity on the probabilistic relationship. As expected, when sensitivity decreases, the distributions of resistivity for the different facies tend to be superimposed. A mean distribution thus overestimates the ability of surface ERT to discriminate hydrofacies in depth. [less ▲]

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See detailAssessing Emigrant Participation in Home Country Elections: The Case of Mexico’s 2006 Presidential Election
Lafleur, Jean-Michel ULg; Calderon Chelius, Leticia

in International Migration (2011), 49(3), 99-124

How did Mexican migrants react to the opportunity to formally participate for the first time in home country politics during the 2006 Presidential Election? In this paper, we attempt to explain the low ... [more ▼]

How did Mexican migrants react to the opportunity to formally participate for the first time in home country politics during the 2006 Presidential Election? In this paper, we attempt to explain the low level of migrant voter registration in home country elections. Grounding ourselves on the existing literature on voter turnout, we verify two hypotheses that focus (1) on the role of Mexican authorities, and (2) on the interest of migrants and migrant associations in home country politics. Building on the case of Mexico, the paper concludes with proposing a series of variables upon which we suggest research could focus in order to assess migrant voter turnout in home country elections. [less ▲]

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See detailAssessing employees propensity to engage in OCB: incremental validity of SJT beyond personality.
Lothe, Benoit ULg; Hansez, Isabelle ULg; Scius, Anthony et al

Conference (2015, May 21)

This study presents the validation results of a SJT developed in collaboration with a Belgian french speaking mutual insurance company for the assessment of employees OCB. The purpose is to provide ... [more ▼]

This study presents the validation results of a SJT developed in collaboration with a Belgian french speaking mutual insurance company for the assessment of employees OCB. The purpose is to provide empirical evidence concerning the validity of using the SJT by examining the issues of OCB criterion validity, incremental validity beyond a personality inventory, applicant perception and SJT transparency level. The SJT was developed in-house and following relevant literature recommendations (Weekley, Ployhart & Holtz, 2006). Data were collected on 117 white-collar employees. Three other measurements were concurrently collected: OCB using Williams & Anderson (1991) self-reported scales, personality using the Gosling, Rentfrow & Swann (2003) ten item inventory (TIPI) and applicant perception using SPJS (Bauer, & al., 2001). An open-ended question was used to access the extent to which applicants are able to identify the SJT criteria. Results indicated that the SJT is a relevant predictor of OCB (r = .42; p<.001). The SJT also provides incremental explanation of the OCB criteria beyond the personality inventory (∆R² = .11; p<.001). There was in average an agreement about the acceptability of the SJT in terms of perceived procedural justice. No relationships were found between applicant ability to correctly identify the SJT criteria and SJT score or OCB self-rating. This study is to our knowledge among the first attempt to develop and validate a tool to fill the gap on how to predict employees OCB (Organ, Podsakoff & Podsakoff, 2010). Implications for the personnel selection and current limitations will be discussed. [less ▲]

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See detailAssessing fitness in endurance horses
Fraipont, Audrey ULg; Van Erck, Emmanuelle; Ramery, Eve ULg et al

in Canadian Veterinary Journal = Revue Vétérinaire Canadienne (2012), 53

A field test and a standardized treadmill test were used to assess fitness in endurance horses. These tests discriminated horses of different race levels: horses participating in races of 120km and more ... [more ▼]

A field test and a standardized treadmill test were used to assess fitness in endurance horses. These tests discriminated horses of different race levels: horses participating in races of 120km and more showed higher values of VLA4 (velocity at which blood lactate reached 4 mmol/L) and V200 (velocities at which heart rates reached 200 beats per min) than horses of lower race levels. [less ▲]

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See detailAssessing gaps and needs for integrating building performance optimization tools in net zero energy buildings design
Attia, Shady ULg; Hamdy, Mohamed; O’Brien, William et al

in Energy and Buildings (2013), 60

This paper summarizes a study undertaken to reveal potential challenges and opportunities for integrating optimization tools in net zero energy buildings (NZEB) design. The paper reviews current trends in ... [more ▼]

This paper summarizes a study undertaken to reveal potential challenges and opportunities for integrating optimization tools in net zero energy buildings (NZEB) design. The paper reviews current trends in simulation-based building performance optimization (BPO) and outlines major criteria for optimization tools selection and evaluation. This is based on analyzing user's needs for tools capabilities and requirement specifications. The review is carried out by means of a literature review of 165 publications and interviews with 28 optimization experts. The findings are based on an inter-group comparison between experts. The aim is to assess the gaps and needs for integrating BPO tools in NZEB design. The findings indicate a breakthrough in using evolutionary algorithms in solving highly constrained envelope, HVAC and renewable optimization problems. Simple genetic algorithm solved many design and operation problems and allowed measuring the improvement in the optimality of a solution against a base case. Evolutionary algorithms are also easily adapted to enable them to solve a particular optimization problem more effectively. However, existing limitations including model uncertainty, computation time, difficulty of use and steep learning curve. Some future directions anticipated or needed for improvement of current tools are presented. [less ▲]

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See detailAssessing groundwater-surface water interaction and groundwater discharge in a contaminated site in an industrial, sub-urbanized area
Batlle-Aguilar, Jordi; Brouyère, Serge ULg

in Davis, G. B.; Johntson, C. D.; Trefry, M. G. (Eds.) Groundwater Quality 2007 Securing Groundwater Quality in Urban and Industrial Environments (2007)

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See detailAssessing heat stress effects on production traits of Holsteins in a temperate region
Hammami, Hedi ULg; Bormann, Jeanne; Gengler, Nicolas ULg

in Book of abstracts of the 63rd Annual Meeting of the European Association for Animal Production (2012)

Heat stress impaired productive, reproductive and animal behaviour. Examination of milk production loss due to heat stress was mainly evaluated in USA and few tropical countries using the temperature ... [more ▼]

Heat stress impaired productive, reproductive and animal behaviour. Examination of milk production loss due to heat stress was mainly evaluated in USA and few tropical countries using the temperature humidity index (THI1) developed in the 1950’s. The main objective of this study was to evaluate the effects of six new environmental stress indices on production traits in a temperate region. These indices include solar radiation and wind speed in addition to the temperature and humidity only defining THI1. For that purpose, 530820 milk, fat, protein, and somatic cell count first-lactation test-day records (TD) collected between 2000 and 2011 in Luxembourg were used. TD records were merged with meteorological data from 14 public weather stations. Each TD was assigned to the average daily thermal index of the 3 days before. Firstly, broken-line regression models were applied to identify the threshold of heat stress (THR) for each of the thermal indices. The decline of daily production of the different traits above THR point was assessed by mixed linear models including regression on unit of each of the thermal index. Estimates of THR were specific to each thermal index and trait. Significant decrease of milk, fat and protein yields above THR was observed for all studied thermal predictors. Whereas, an increase of the somatic cell score was observed above the specific THR point. THR estimates for THI1 and THI6 were of 68 and 80 and 62 and 78 for milk and protein yields respectively. Respective rate of decline per unit were of 0.243 and 0.188 kg and 0.0045 and 0.0051 kg respectively. Results from this phenotypic analysis show that evaluating heat tolerance based on bio-meteorological indicators is promising and phenotypic and genetic implications should be investigated. [less ▲]

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See detailAssessing heat tracing experiment data sets for direct forecast of temperature evolution in subsurface models: an example of well and geophysical monitoring data
Hermans, Thomas ULg; Oware, Erasmus; Klepikova, Maria et al

Scientific conference (2016, May 04)

Hydrogeological inverse modeling is used for integrating data and calibrating subsurface model parameters. On one hand, deterministic approaches are relatively fast but fail to catch the uncertainty ... [more ▼]

Hydrogeological inverse modeling is used for integrating data and calibrating subsurface model parameters. On one hand, deterministic approaches are relatively fast but fail to catch the uncertainty related to the spatial distribution of model parameters. On the other hand, stochastic inverse modeling is time-consuming and sampling the full high-dimensional parameter space is generally impossible. Even then, the end result is not the inverted model itself, but the forecast built from such models. In this study, we investigate a prediction-focused approach (PFA) in order to derive a direct statistical relationship between data and forecast without explicitly calibrating any models to the data. To derive this relationship, we first sample a limited number of models from the prior distribution using geostatistical methods. For each model, we then apply two forward simulations: the first corresponds to the forward model of the data (past), the second corresponds to the forward model of the forecast (future). The relationship between observed data and forecast is generally highly non-linear, depending on the complexity of the prior distribution and the differences in the two forward operators. In order to derive a useful relationship, we first reduce the dimension of the data and the forecast through principal component analysis (PCA) related techniques in order to keep the most informative part of both sets. Then, we apply canonical correlation analysis (CCA) to establish a linear relationship between data and forecast in the reduced space components. If such a relationship exists, it is possible to directly sample the posterior distribution of the forecast with a multi-Gaussian framework. In this study, we apply this methodology to forecast the evolution with time of the distribution of temperature in a control panel in an alluvial aquifer. We simulate a heat tracing experiment monitored with both well logging probes and electrical resistivity tomography. We show (1) that the proposed method can be used to quantify the uncertainty on the forecast both spatially and temporally and (2) that spatially-distributed data acquired through geophysical methods help to significantly reduce the uncertainty of the posterior. [less ▲]

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See detailAssessing heat tracing experiment data sets for direct forecast of temperature evolution in subsurface models: an example of well and geophysical monitoring data
Hermans, Thomas ULg; Klepikova, Maria; Caers, Jef

Conference (2016, April 21)

Hydrogeological inverse modeling is used for integrating data and calibrating subsurface model parameters. On one hand, deterministic approaches are relatively fast but fail to catch the uncertainty ... [more ▼]

Hydrogeological inverse modeling is used for integrating data and calibrating subsurface model parameters. On one hand, deterministic approaches are relatively fast but fail to catch the uncertainty related to the spatial distribution of model parameters. On the other hand, stochastic inverse modeling is time-consuming and sampling the full high-dimensional parameter space is generally impossible. Even then, the end result is not the inverted model itself, but the forecast built from such models. In this study, we investigate a prediction-focused approach (PFA) in order to derive a direct statistical relationship between data and forecast without explicitly calibrating any models to the data. To derive this relationship, we first sample a limited number of models from the prior distribution using geostatistical methods. For each model, we then apply two forward simulations: the first corresponds to the forward model of the data (past), the second corresponds to the forward model of the forecast (future). The relationship between observed data and forecast is generally highly non-linear, depending on the complexity of the prior distribution and the differences in the two forward operators. In order to derive a useful relationship, we first reduce the dimension of the data and the forecast through principal component analysis (PCA) related techniques in order to keep the most informative part of both sets. Then, we apply canonical correlation analysis (CCA) to establish a linear relationship between data and forecast in the reduced space components. If such a relationship exists, it is possible to directly sample the posterior distribution of the forecast with a multi-Gaussian framework. In this study, we apply this methodology to forecast the evolution with time of the distribution of temperature in a control panel in an alluvial aquifer. We simulate a heat tracing experiment monitored with both well logging probes and electrical resistivity tomography. We show (1) that the proposed method can be used to quantify the uncertainty on the forecast both spatially and temporally and (2) that spatially-distributed data acquired through geophysical methods help to significantly reduce the uncertainty of the posterior. [less ▲]

Detailed reference viewed: 51 (5 ULg)