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See detailMethodology of the biological risk classification of animal pathogens in Belgium
Van Vaerenbergh, B.; Koenen, Frank; Pauwels, K. et al

in Revue Scientifique et Technique / Office International des Epizooties = Revista Cientifica y Tecnica / Officina Internacional de Epizootias = Scientific and Technical Review / International Office of Epizootics (2010), 29(3), 513-522

The biological hazards posed by micro-organisms have lead to their categorisation into risk groups and the elaboration of classification lists. Current classification systems rely on criteria defined by ... [more ▼]

The biological hazards posed by micro-organisms have lead to their categorisation into risk groups and the elaboration of classification lists. Current classification systems rely on criteria defined by the World Health Organization, considering the severity of the disease the micro-organism might cause, its ability to spread and the availability of prophylaxis or efficient treatment. Animal pathogens are classified according to the definitions of the World Organization of Animal Health whereby also economic aspects are considered. In Europe, classification is often directly linked to containment measures. The Belgian classification however, considers only the inherent characteristics of the micro-organism, not its use, making it independent of containment measures. Also a common list for human and animal pathogens is elaborated, allowing a comprehensive approach. Evolution of scientific knowledge requires regular updating of classification lists. This paper describes the particularities of the Belgian classification and the methodology that was used for its peer-reviewed revision, hereby focusing on animal pathogens. [less ▲]

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See detailA methodology to assess the exactness of Stream Network modeling process on agricultural watersheds
Ouedraogo, Mohamar ULg; Degre, Aurore ULg; Beckers, Eléonore ULg et al

in Geophysical Research Abstracts (2011)

The goal of our study is to evaluate the exactness of stream network modeling process on agricultural watersheds. Agricultural watersheds topography is always changing, making it difficult to be modeled ... [more ▼]

The goal of our study is to evaluate the exactness of stream network modeling process on agricultural watersheds. Agricultural watersheds topography is always changing, making it difficult to be modeled. According to the standard ISO-7078 (ISO-7078, 1985) of the Inernational Organization of Standardization, the exactness of a measurement process or a modeled process can be defined as the difference between results obtained from the measurement process and a reference accepted as the «true value». A small watershed of a dozen hectares size has been surveyed by terrestrial LiDAR (Light Detecting And Ranging) scanner and photogrammetrical techniques to produce a row data of 30 cm resolution. Three interpolation techniques i.e. natural neighbourg, multiquadratic radial basis function and inverse distance weighted have been applied on the original data to create original digital elevation models (DEM) of 1 m resolution. RTK (Real Time Kinematics) GPS (Global Positionning System) ground control points have been surveyed on the watershed to evaluate DEM errors and fit a variogram that is used by a conditional sequencial gaussian simulation model to generate error maps. However, ground control point’s elevations accuracy is depending on the microtopography of parcels in an agricultural watershed. Depending on the crop that is planned by the farmer, the soil tillage will be different, and soil structure and roughness can considerably influence ground control point’s elevation. Analysis of variance and geostatistical methods have been applied on total station and RTK GPS data to estimate intervals in which, ground control points elevations vary. These intervals have been estimated for two parcels that soils are tilled in different ways. These errors are added to the generated errors maps to create final error maps. The final errors maps are added to the original DEM to create likely DEM realizations for the watershed (Temme and al., 2007). Then, two spurious sinks filtering methods (Colson 2006; Lindsay and Creed, 2005) and one flat area treatment method (Jenson and Domingue, 1988) are applied on each DEM realization for preprocessing. Finally, the three common flow direction extraction methods (D8, D-infity and Multiple Flow Direction) are applied on each preprocessed DEM to extract stream Network. The extracted stream network is overlapped with RTK GPS field positioned stream network i.e. a polyline format data. To estimate the exactness of the stream extraction methods, the polyline format is converted in raster format. That allows to compute for each pixel of the observed stream network, the distance to the extracted stream network. Then, for each pixel the mean distance can be calculated, and can be represented through the stream network. LiDAR technology is becoming useful for environment modeling because of his accuracy. Such quantity of data is not free of errors. This research will allow us to estimate the uncertainty of stream network modeled from agricultural watersheds by considering the main sources of errors that are propagated through computing processes. [less ▲]

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See detailMethodology to characterize a residential building stock using a bottom-up approach: a case study applied to Belgium
Gendebien, Samuel ULg; Georges, Emeline ULg; Bertagnolio, Stéphane et al

in International Journal of Sustainable Energy Planning and Management (2014)

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See detailMethodology to fish peptide ligands of nAChRs from Cone snail venoms by MALDI-TOF mass spectrometry
Echterbille, Julien ULg; Gilles, Nicolas; Araoz, Romulo et al

Poster (2016, June)

More than 50,000 of venomous species are currently indexed in the world. Each of their venom is composed of hundreds of toxins which potentially exhibit a high selectivity for membrane receptors such as ... [more ▼]

More than 50,000 of venomous species are currently indexed in the world. Each of their venom is composed of hundreds of toxins which potentially exhibit a high selectivity for membrane receptors such as GPCRs or ion channels. Among them, nAChRs are a target for drug discovery, primarily for treating central nervous system troubles. Therefore, the discovery of pharmacological tools and innovative drugs targeting nAChRs from animal venoms appears as an evidence. This study proposes the use a mass-spectrometry based methodology1 to discover new nAChRs ligands from cone snails venoms, and particularly -conotoxins (a-CTXs), known as potential antagonists of nAChRs2. in few words, Torpedo membranes, containing a high concentration of nAChRs, are incubated with BSA tryptic digests (>100 peptides) doped by small amounts of known a-CTXs. After two hours incubation, free (i.e. containing molecules remaining in solution) and bound (i.e. peptides bound to the membranes) fractions were analyzed with a MALDI-TOF/TOF mass spectrometer. The POC (positive and negative controls) as well as a real screening of Conus ermineus venom are presented. [less ▲]

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See detailA Methodology to Improve the Robustness of Gas Turbine Engine Performance Monitoring Against Sensor Faults
Dewallef, Pierre ULg; Borguet, Sébastien ULg

in Journal of Engineering for Gas Turbines and Power (2013), 135(5),

For turbine engine performance monitoring purposes, system identification techniques are often used to adapt a turbine engine simulation model to some measurements performed while the engine is in service ... [more ▼]

For turbine engine performance monitoring purposes, system identification techniques are often used to adapt a turbine engine simulation model to some measurements performed while the engine is in service. Doing so, the simulation model is adapted through a set of so-called health parameters whose values are intended to represent a faithful image of the actual health condition of the engine. For sake of low computational burden, the problem of random errors contaminating the measurements is often considered to be zero-mean, white and Gaussian random variables. However, when a sensor fault occurs, the measurement errors no longer satisfy the Gaussian assumption and the results given by the system identification rapidly become unreliable. The present contribution is dedicated to the development of a diagnosis tool based on a Kalman filter whose structure is slightly modified in order to accommodate sensor malfunctions. The benefit in terms of the diagnostic reliability of the resulting tool is illustrated on several sensor faults that may be encountered on a current turbofan layout. [less ▲]

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See detailMethodology to model the energy vulnerability of households in Europe based on the current mapping of fuel poverty and transport poverty and its likely evolution until 2040
Pierson, Charlotte; Reiter, Sigrid ULg

in Proceedings of the Urban Transition Global Summit 2016 (2016)

Fuel poverty refers to a situation in which an individual or household is not able to meet their basic energy needs. Fuel poverty is currently growing in the European Union. Research in this field is ... [more ▼]

Fuel poverty refers to a situation in which an individual or household is not able to meet their basic energy needs. Fuel poverty is currently growing in the European Union. Research in this field is often limited to the assessment of the current risk of fuel poverty based on energy consumptions due to housing. Urban sprawl generates a significant increase in energy consumption related to daily mobility, which generates energy poverty related to transportation needs. This article presents a methodology for modeling the current and future energy poverty of households in Europe on the basis of energy consumptions due to housing, to daily mobility and their combination. Indicators for fuel poverty and transport poverty will be based on Hills’ method, which is widely recognized internationally for fuel poverty assessment and which takes into account two thresholds: energy expenses of households and their available residual income. This article will outline the spatial modeling process of energy costs due to dwellings and mobility thanks to the coupling of a GIS tool, cadastral datasets, existing methods for the assessment of buildings and transport energy consumptions and updated databases (EPB certificates, detailed mobility surveys, data from smart meters, mobile phones and GPS). Different scenarios will be selected to predict the evolution of fuel and transport poverty until 2040 on the basis of national and European prospective studies or, alternatively, based on the historical evaluation of some key parameters and their extrapolation. The evolution of built-up areas will be model thanks to the multinomial logistic regression model (MLR) that enables to visualize the consequence of different urban densities expansion. The different parameters that will influence the evolution of fuel and transport poverty until 2040 will be highlighted (climate change, urban expansion, fuel prices, energy performance of buildings and vehicles, etc.). [less ▲]

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See detailMethodology used for the European badger (Meles meles) monitoring in Wallonie
Schockert, Vincianne ULg; Lambinet, Clotilde ULg; Cornet, Yves ULg et al

in Lecocq, Yves (Ed.) Abstracts of 31st IUGB congress (2013, August)

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See detailMethods
Richelle, Marc ULg; Lejeune, Helga ULg; Mantanus, H. et al

in Richelle, Marc; Lejeune, Helga (Eds.) Time in animal behaviour (1980)

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See detailMethods and means for metabolic engineering and improved product formation by micro-organisms
Rigali, Sébastien ULg; Titgemeyer, Fritz; van Wezel, Gilles

Patent (2007)

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See detailMethods and models for brain connectivity assessment across levels of consciousness
Amico, Enrico ULg

Doctoral thesis (2016)

The human brain is one of the most complex and fascinating systems in nature. In the last decades, two events have boosted the investigation of its functional and structural properties. Firstly, the ... [more ▼]

The human brain is one of the most complex and fascinating systems in nature. In the last decades, two events have boosted the investigation of its functional and structural properties. Firstly, the emergence of novel noninvasive neuroimaging modalities, which helped improving the spatial and temporal resolution of the data collected from in vivo human brains. Secondly, the development of advanced mathematical tools in network science and graph theory, which has recently translated into modeling the human brain as a network, giving rise to the area of research so called Brain Connectivity or Connectomics. In brain network models, nodes correspond to gray-matter regions (based on functional or structural, atlas-based parcellations that constitute a partition), while links or edges correspond either to structural connections as modeled based on white matter fiber-tracts or to the functional coupling between brain regions by computing statistical dependencies between measured brain activity from different nodes. Indeed, the network approach for studying the brain has several advantages: 1) it eases the study of collective behaviors and interactions between regions; 2) allows to map and study quantitative properties of its anatomical pathways; 3) gives measures to quantify integration and segregation of information processes in the brain, and the flow (i.e. the interacting dynamics) between different cortical and sub-cortical regions. The main contribution of my PhD work was indeed to develop and implement new models and methods for brain connectivity assessment in the human brain, having as primary application the analysis of neuroimaging data coming from subjects at different levels of consciousness. I have here applied these methods to investigate changes in levels of consciousness, from normal wakefulness (healthy human brains) or drug-induced unconsciousness (i.e. anesthesia) to pathological (i.e. patients with disorders of consciousness). [less ▲]

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See detailMethods for calculating growth velocity for VLBW infants
SENTERRE, Thibault ULg

in Pediatrics (2015), 136(1), 8469757

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See detailMethods for Estimating Areas under Receiver-Operating Characteristic Curves: Illustration with Somatic-Cell Scores in Subclinical Intramammary Infections
Detilleux, Johann ULg; Arendt, J.; Lomba, F. et al

in Preventive Veterinary Medicine (1999), 41(2-3), 75-88

The aim of this study was to demonstrate receiver-operating characteristic (ROC) methodology in the context of bovine intramammary infection (IMI). Quarter somatic cell scores (SCS) were available to ... [more ▼]

The aim of this study was to demonstrate receiver-operating characteristic (ROC) methodology in the context of bovine intramammary infection (IMI). Quarter somatic cell scores (SCS) were available to evaluate quarter IMI, and the final IMI diagnosis was made from milk bacteriologic cultures. Data consisted of 11,453 quarter-milk samples collected on 2084 clinically healthy cows located in 154 Belgian herds. Bacteriological analyses showed 16.2%, 7.2%, and 11.9% of quarters infected with coagulase-positive Staphylococcus spp., Streptococcus agalactiae, and coagulase-negative Staphylococcus spp., respectively. The ROC curve indicated all the combinations of sensitivity and specificity that quarter SCS was able to provide as a test to identify quarter IMI. Among parametric, semi-parametric, and non-parametric methods to estimate area under ROC curves, the parametric method seemed the least appropriate for analyzing SCS in this study. With the non-parametric method, the total area under the ROC curves showed quarter SCS could identify quarter IMI with an overall accuracy of 69%, 76%, and 59% for coagulase-positive Staphylococcus spp., S. agalactiae, and coagulase-negative Staphylococcus spp., respectively. Parametric and non-parametric statistical tests showed that overall SCS diagnostic capability was significantly (p<0.01) different from chance and was different (p<0.01) across the three bacteria. However, the SCS thresholds yielding the highest percentage of quarters correctly classified as infected (for the observed prevalence and for equal costs assigned to false-positive and false-negative results) were so high that they had no practical value. The major advantage of ROC analysis is the comprehensive description of the discrimination capacity of SCS for all possible choices of critical values. The major disadvantage is the dependency upon the gold standard used for the final diagnosis--but recent improvements of the methodology will correct the problem. [less ▲]

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See detailMethods for size classification of wood chips
Hartmann, Hans; Böhm, Thorsten; Daugbjerg Jensen, Peter et al

in Biomass & Bioenergy (2006)

Methods for size classification of wood chips were analysed in an international round robin using 13 conventional wood chip samples and two specially prepared standard samples, one from wood chips and one ... [more ▼]

Methods for size classification of wood chips were analysed in an international round robin using 13 conventional wood chip samples and two specially prepared standard samples, one from wood chips and one from hog fuel. The true size distribution of these two samples (according to length, width and height) had been determined stereometrically (reference method) using a digital calliper gauge and by weighing each of the about 7000 wood particles per sample. Five different horizontal and three rotary screening devices were tested using five different screen hole diameters (3.15, 8, 16, 45, 63 mm, round holes). These systems are compared to a commercially available continuously measuring image analysis equipment. The results show that among the devices of a measuring principle—horizontal and rotary screening—the results are quite comparable, while there is a severe incompatibility when distributions are determined by different measuring principles. Highest conformity with the reference values is given for measurements with an image analysis system, whereas for all machines with horizontal screens the median value of the size distribution only reached between one-third to half of the reference median value for the particle length distribution. These deviations can be attributed to a higher particle misplacement, which is particularly found in the larger fractions. Such differences decrease when the particle’s shape is more roundish (i.e. sphericity closer to one). The median values of length distributions from screenings with a rotary classifier are between the measurements from an image analysis and horizontal screening devices. [less ▲]

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See detailMethods for the preparation of bimetallic xerogel catalysts designed for chlorinated wastes processing
Lambert, Stéphanie ULg; Ferauche, Fabrice; Heinrichs, Benoît ULg et al

in Journal of Non-Crystalline Solids (2006), 352(26-27), 2751-2762

The aim of this work is to simplify and generalize the synthesis procedure of bimetallic supported catalysts by sol-gel process. For Pd-Ag/SiO2, co-gelled xerogels catalysts a number of synthesis ... [more ▼]

The aim of this work is to simplify and generalize the synthesis procedure of bimetallic supported catalysts by sol-gel process. For Pd-Ag/SiO2, co-gelled xerogels catalysts a number of synthesis procedures were compared: use of one or two specific alkoxides able to form a chelate with palladium and/or silver cations, reagent mixing in one or two steps, use of industrial grade chemicals instead of laboratory grade chemicals. The catalysts obtained are quite similar: same metal dispersion, same tailored morphology, same localization and accessibility of Pd-Ag alloy nanoparticles inside microporous silica, same activity and selectivity for hydrodechlorination of 1,2-dichloroethane into ethylene. For catalyst production at large scale the synthesis can be achieved in one step with 3-(2-aminoethyl)aminopropyltrimethoxysilane of industrial grade as chelating alkoxide, tetraethylorthosilicate (TEOS) of industrial grade and ethanol denatured with diethyl phthalate. (c) 2006 Elsevier B.V. All rights reserved. [less ▲]

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See detailMethods for Vitamin D measurement - analytical problems and clinical relevance
Cavalier, Etienne ULg

Conference (2010, March 05)

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See detailMethods in social cognition research
Dardenne, Benoît ULg

Scientific conference (1992)

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See detailMethods of clinical and biological assessment of rheumatoid arthritis
Malaise, Michel ULg; Franchimont, P.

in Scandinavian Journal of Rheumatology. Supplement (1987), 65

Inflammation has long been recognised as notoriously difficult to measure both in clinical practice and in the laboratory. Of all the cardinal features of inflammation, pain relief is really what the ... [more ▼]

Inflammation has long been recognised as notoriously difficult to measure both in clinical practice and in the laboratory. Of all the cardinal features of inflammation, pain relief is really what the patients want, and among disabled persons, rheumatic patients are the only ones who must cope with chronic pain. The rheumatologist, however, is also interested in other parameters that are thought to reflect improvement of the inflammatory process. The methods used to clinically assess rheumatoid arthritis (RA) should share the following four parameters: validity, sensitivity, reliability and simplicity. Unfortunately, at present, no single ideal method is capable of accurately reflecting disease activity in RA. The measurement of pain relief by the visual analogue scale, the determination of the Ritchie index and the duration of morning stiffness, plus patient assessment of global response should be enough to detect clinical activity of the drug in RA. If we are working with slow-acting drugs or so-called disease modifying antirheumatic drugs (DMARDs), it should be appropriate to include X-ray analysis and laboratory tests in the evaluation. A reduction in the number of fresh erosions and/or the healing of present erosions can give reliable information on the capacity of the drug to really modify the course of the disease. At present, measurement of the erythrocyte sedimentation rate and of acute phase serum proteins seems to offer the best available assessment during early weeks of therapy. The other biological tests are of limited value in reflecting or predicting a beneficial clinical response to DMARDs. [less ▲]

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