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See detailAssessment of changes in soil organic matter after invasion by exotic plant species
Koutika, Lydie*-Stella; Vanderhoeven, SONIA ULg; Chapuis-Lardy, Lydie et al

in Biology & Fertility of Soils (2007), 44(2), 331-341

Invasive exotic plants can modify soil organic matter (SOM) dynamics and other soil properties. We evaluated changes in particulate organic matter (POM) and carbon (C) mineralisation in adjacent plots ... [more ▼]

Invasive exotic plants can modify soil organic matter (SOM) dynamics and other soil properties. We evaluated changes in particulate organic matter (POM) and carbon (C) mineralisation in adjacent plots invaded by Solidago gigantea, Prunus serotina, Heracleum mantegazzianum and Fallopia japonica, and non-invaded control plots on different soils in Belgium. Litter decomposition of S. gigantea and P. serotina was compared to that of the native species Epilobium hirsutum, Betula pendula and Fagus sylvatica. Disregarding the differences in site characteristics (soil texture, parental material and plant species), we argued that the invasion by S. gigantea and P. serotina enhance SOM dynamics by increasing C mineralisation in 2 out of 3 sites invaded by S. gigantea and in 1 out of 3 sites invaded by P. serotina; C in coarse POM (cPOM, 4,000-250 mu m) and fine POM (fPOM, 250-50 mu m) in 1 site invaded by S. gigantea and C content in total POM (tPOM, 4,000-50 mu m) and the organo-mineral fraction (OMF, 0-50 mu m) in 1 site invaded by P. serotina. H. mantegazzianum and F. japonica slowed down SOM dynamics by reducing C mineralisation in three out of four sites; C and nitrogen (N) of fPOM in the invaded compared with the non-invaded plots at one site invaded by H. mantegazzianum. However, N content of cPOM (4,000-250 mu m) was higher in the invaded sites by F. japonica compared with the non-invaded plots. Our results indicated that the effects of invasion by exotic plant species were not species-specific but site-specific. [less ▲]

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See detailAssessment of Complex Perineal Fistulas
Bruyninx, Luc ULg; Meunier, Paul ULg

in Acta Chirurgica Belgica (2000), 100(3, May-Jun), 115-7

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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 & 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 detailAssessment of consciousness with electrophysiological and neurological imaging techniques.
Bruno, Marie-Aurélie ULg; Gosseries, Olivia ULg; Ledoux, Didier ULg et al

in Current Opinion in Critical Care (2011)

PURPOSE OF REVIEW: Brain MRI (diffusion tensor imaging and spectroscopy) and functional neuroimaging (PET, functional MRI, EEG and evoked potential studies) are changing our understanding of patients with ... [more ▼]

PURPOSE OF REVIEW: Brain MRI (diffusion tensor imaging and spectroscopy) and functional neuroimaging (PET, functional MRI, EEG and evoked potential studies) are changing our understanding of patients with disorders of consciousness encountered after coma such as the 'vegetative' or minimally conscious states. RECENT FINDINGS: Increasing evidence from functional neuroimaging and electrophysiology demonstrates some residual cognitive processing in a subgroup of patients who clinically fail to show any response to commands, leading to the recent proposal of 'unresponsive wakefulness syndrome' as an alternative name for patients previously coined 'vegetative' or 'apallic'. SUMMARY: Consciousness can be viewed as the emergent property of the collective behavior of widespread thalamocortical frontoparietal network connectivity. Data from physiological, pharmacological and pathological alterations of consciousness provide evidence in favor of this hypothesis. Increasing our understanding of the neural correlates of consciousness is helping clinicians to do a better job in terms of diagnosis, prognosis and finally treatment and drug development for these severely brain-damaged patients. The current challenge remains to continue translating this research from the bench to the bedside. Only well controlled large multicentric neuroimaging and electrophysiology studies will enable to identify which paraclinical diagnostic or prognostic test is necessary for our routine evidence-based assessment of individuals with disorders of consciousness. [less ▲]

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See detailAssessment of crop based farming systems with a focus on pigeonpea in one selected district in arid and semi-arid lands in the Kenyan coast. Ed. by E. Feoli, D. Pottier, Z. Woldu. Sustainable development of dryland areas of East Africa
Mwang'Ombe, A.W; Olubayo, F; Baudoin, Jean-Pierre ULg et al

in Proceedings of the International Workshop, Addis Ababa, November 9th-12th 1998. European Commission (2000)

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See detailAn assessment of cross-listed firms’ diversification potential
Mouchette, Xavier ULg; Muller, Aline ULg

E-print/Working paper (2014)

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See detailAssessment of detection thresholds of metal oxide sensors based e-nose to the pollution emitted by odorous sources.
Nicolas, Jacques ULg; Romain, Anne-Claude ULg

in Proceedings of the Ninth international symposium on olfaction and electronic nose ISOEN'02 (2002, September)

The paper describes a method to assess the global concentration level of a complex odorous gas mixture which is detected by an electronic nose, and consequently to assess the detection threshold of the ... [more ▼]

The paper describes a method to assess the global concentration level of a complex odorous gas mixture which is detected by an electronic nose, and consequently to assess the detection threshold of the instrument for that particular odour. The studied case is the odour generated by urban waste composting facilities. The measurement is performed in the lab with an array of 12 tin oxide gas sensors on samples collected near the emission. The selected method consists in finding an equivalence between the response of each individual sensor to the concentrations of ethanol used as a standard gas and the responses to various dilution of the original sample. The main issues of that procedure are the order of magnitude of the "concentration" of the non-diluted compost emission sample expressed in ethanol-equivalent and the detection threshold of the sensor array for the compost gas. The latter result requires a suitable definition of the detection threshold, based on the signal to noise ratio. The conclusion is that the detection threshold of Tagushi sensors, expressed in equivalent-ethanol, is generally lower than 1 ppmv and is just slightly higher than the perception threshold of the human nose for the odour gener-ated by compost. [less ▲]

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See detailAssessment of determinants for osteoporosis in elderly men.
Scholtissen, Sophie ULg; Guillemin, F.; Bruyère, Olivier ULg et al

in Osteoporosis International (2009), 20(7), 1157-66

SUMMARY: The aim of this cross-sectional study was to determine and quantify some determinants associated to low bone mineral density (BMD) in elderly men. This study showed that ageing, a lower body mass ... [more ▼]

SUMMARY: The aim of this cross-sectional study was to determine and quantify some determinants associated to low bone mineral density (BMD) in elderly men. This study showed that ageing, a lower body mass index (BMI), a higher blood level of C-terminal cross-linking telopeptides of type I collagen (CTX-1), family history of osteoporosis, and/or fracture and prior fracture were associated with bone mineral density. INTRODUCTION: Our aims were to identify some determinants associated to low bone mineral density in men and to develop a simple algorithm to predict osteoporosis. METHODS: A sample of 1,004 men aged 60 years and older was recruited. Biometrical, serological, clinical, and lifestyle determinants were collected. Univariate, multivariate, and logistic regression analyses were performed. Receiver operating characteristic analysis was used to assess the discriminant performance of the algorithm. RESULTS: In the multiple regression analysis, only age, BMI, CTX-1, and family history of osteoporosis and/or fracture were able to predict the femoral neck T-score. When running the procedure with the total hip T-score, prior fracture also appeared to be significant. With the lumbar spine T-score, only age, BMI, and CTX-1 were retained. The best algorithm was based on age, BMI, family history, and CTX-1. A cut-off point of 0.25 yielded a sensibility of 78%, a specificity of 59% with an area under the curve of 0.73 in the development and validation cohorts. CONCLUSION: Ageing, a lower BMI, higher CTX-1, family history, and prior fracture were associated with T-score. Our algorithm is a simple approach to identify men at risk for osteoporosis. [less ▲]

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See detailAssessment of developmental outcome of preterm babies
Battisti, Oreste ULg

in Archives de Pédiatrie (1998), 5

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See detailAssessment of disease activity in rheumatoid arthritis with F-18-FDG PET
Beckers, Catherine ULg; Ribbens, Clio ULg; Andre, Béatrice ULg et al

in Journal of Nuclear Medicine (2004), 45(6), 956-964

The aim of this study was to assess synovitis by F-18-FDG PET in an individual joint analysis and in a global analysis of rheumatoid arthritis (RA) disease activity and to compare F-18-FDG PET parameters ... [more ▼]

The aim of this study was to assess synovitis by F-18-FDG PET in an individual joint analysis and in a global analysis of rheumatoid arthritis (RA) disease activity and to compare F-18-FDG PET parameters with clinical, biologic, and sonographic (US) rheumatoid parameters. Methods: Three hundred fifty-six joints were assessed in 21 patients with active RA: the knees in all subjects and either wrists as well as metacarpophalangeal and proximal interphalangeal joints in 13 patients, or ankles and the first metatarsophalangeal joints in the remaining 8 patients. PET analysis consisted of a visual identification of F-18-FDG uptake in the synovium and measurements of standardized uptake values (SUVs). Independent assessors performed the clinical and US examinations. Results: PET positivity was found in 63% of joints, whereas 75%, 79%, and 56% were positive for swelling, tenderness, and US analysis, respectively. Both the rate of PET-positive joints and the SUV increased with the number of positive parameters present (swelling, tenderness, US positivity) and with the synovial thickness. The mean SUV was significantly higher in joints where a power Doppler signal was found. In a global PET analysis, the number of PET-positive joints and the cumulative SUV were significantly correlated with the swollen and tender joint counts, the patient and physician global assessments, the erythrocyte sedimentation rate and C-reactive protein serum levels, the disease activity score and the simplified disease activity index, the number of US-positive joints, and the cumulative synovial thickness. Conclusion: F-18-FDG PET is a unique imaging technique that can assess the metabolic activity of synovitis and measure the disease activity in RA. [less ▲]

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See detailAssessment of ease of use and experience of the new paediatric triple-chamber bag for parenteral nutrition for preterm infants
Rigo, J; Marlowe, ML; Bonnot, D et al

in Intensive Care Medicine (2011), 37(S2), 396

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See detailAssessment of endoscopic activity lndex and biological lnflammatory markers in clinically active Crohn's disease with normal C-reactive protein serum level
Denis, Marie-Armelle; Reenaers, Catherine ULg; Fontaine, Fernand et al

in Inflammatory Bowel Diseases (2007), 13(9), 1100-1105

Background: Patients with clinically active Crohn's disease (CD), defined by a Crohn's Disease Activity Index (CDAI) > 150, may have normal Greactive protein (CRP) serum levels. In such cases, it is ... [more ▼]

Background: Patients with clinically active Crohn's disease (CD), defined by a Crohn's Disease Activity Index (CDAI) > 150, may have normal Greactive protein (CRP) serum levels. In such cases, it is difficult to know whether these patients have really active disease or rather functional symptoms. This distinction is important to decide the most appropriate treatment. The aim of our work was to assess intestinal and colonic lesions in such patients and to look for biological markers potentially associated with endoscopic activity of the disease. Methods: We included 28 consecutive CD patients with CDAI >150 and a normal CRP level. These patients underwent a full colonoscopy with Crohn's Disease Endoscopy Index of Severity (CDEIS) calculation, fecal calprotectin, blood fibrinogen, acid a-I glycoprotein, and erythrocyte sedimentation rate measurement. The Harvey-Bradshaw score was also calculated. Serum ILI beta, IL6, IL8, sIL2R, and sTNFR2 were measured. Results: The median CDAI was 181 (151-485). Almost all (92.9%) these patients had endoscopic lesions, but the majority had only mild lesions (CDEIS : 6). No correlation was found between CDEIS and any of the clinical or biological markers. However, all the patients with significant endoscopic lesions (defined by a CDEIS >6) had previous surgical intestinal resection and lesions involving the anastomosis. Conclusions: Patients with elevated CDAT and normal CRP have only mild mucosal lesions of CD. Most significant lesions may be observed at the anastomosis and proximal to it in previously operated patients. None of the biological markers tested was associated with these endoscopic lesions. [less ▲]

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See detailAssessment of equine diaphragm strength and activation using transvenous phrenic nerve stimulation
Desmecht, Daniel ULg; Linden, Annick ULg; Lekeux, Pierre ULg

in Equine Veterinary Journal. Supplement (1995), 18

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See detailAssessment of erythromycin toxicity on activated sludge via batch experiments and microscopic techniques (epifluorescence and CLSM)
Louvet, Jean-Noël ULg; Helouin, Yannick; Attik, Ghania et al

in Process Biochemistry (2010), 45

This study investigates erythromycin toxicity toward activated sludge as a function of exposure time and antibiotic concentration. Batch experiments were conducted and microscopic techniques ranging from ... [more ▼]

This study investigates erythromycin toxicity toward activated sludge as a function of exposure time and antibiotic concentration. Batch experiments were conducted and microscopic techniques ranging from bright-field microscopy to epifluorescence and confocal laser scanning microscopy (CLSM), combined with a fluorescent viability indicator (BacLight ® Bacterial Viability Kit, Molecular Probes), allowed us to study erythromycin time-kill activity. The erythromycin toxicity was observed at lower concentration when exposure time increased. A 4 .g/L erythromycin concentration was toxic to heterotrophic bacteria on a 5-day time exposure, and a 5 mg/L concentration inhibited nitrification. These findings are in agreement with the microscopic studies, which showed a latency time before the lower antibiotic concentrations began to kill bacteria. Microscope slide wells were used as micro-reactors in which erythromycin concentration ranged from 0.1 to 1 mg/L. After 45 min there were 94% (SD 3.8) of living bacteria in control micro-reactors, 67% (SD 3.1) in micro-reactors that contained 0.1 mg/L erythromycin and 37% (SD 18.6) in micro-reactors that contained 1 mg/L erythromycin. CLSM allowed visualization of isolated stained cells in the three-dimensional structure of damaged flocs [less ▲]

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See detailAssessment of Eurocode 5 charring rate calculation methods
Cachim, Paulo; Franssen, Jean-Marc ULg

in Proceedings of the Fifth International Conference Structures in Fire (2008)

The basic hypothesis for the assessment of fire resistance of wood structures is that for temperatures above 300 ºC, wood is no longer able to sustain any load. Consequently, the determination of the ... [more ▼]

The basic hypothesis for the assessment of fire resistance of wood structures is that for temperatures above 300 ºC, wood is no longer able to sustain any load. Consequently, the determination of the location of the 300 ºC isotherm, the charring depth, is decisive for the result of fire resistance calculation methods. Charring rate of wood is dependent of numerous factors, such as wood species (density, permeability or composition), moisture or direction of burning (along or across the grain). Eurocode 5, Part 1-2, presents several methods for the calculation of fire resistance of timber structures that are divided into simplified and advanced. In this paper simplified and advanced methods are compared regarding the calculation of the charring depth. Finite element simulations have been performed, using the proposed wood properties of Eurocode 5 using finite element code SAFIR. The influence of parameters such as wood density, moisture or anisotropy has been investigated. The results obtained with finite element calculations were then compared with Eurocode 5 simplified models. Some inconsistencies between methods have been observed. This paper presents proposals to overcome some of the inconsistencies as well as to extend the applicability of the models. [less ▲]

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