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See detailAssessment of the 3D Localization of Metallic Nanoparticles in Pd/SiO2 Cogelled Catalysts by Electron Tomography
Gommes, Cédric ULg; de Jong, Krijn; Pirard, Jean-Paul ULg et al

in Langmuir (2005), 21

The purpose of this study is to analyze the localization of palladium nanoparticles within their silica support, in two heterogeneous catalysts synthesized by the sol-gel process, with different metal ... [more ▼]

The purpose of this study is to analyze the localization of palladium nanoparticles within their silica support, in two heterogeneous catalysts synthesized by the sol-gel process, with different metal loadings. Electron tomography demonstrates that the palladium particles are localized deep inside the silica skeleton. The use of digital image analysis further shows that the dispersion of palladium is optimal in the sample with the lowest loading. The particles are regularly spaced in the middle of the silica skeleton, with a distance between them comparable to the diameter of the struts of silica. [less ▲]

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See detailAssessment of the acaricidal activity of several plant extracts on the phytophagous mite Tetranychus urticae (Tetranychidae) in Tunisian citrus orchards
Attia, Sabrine; Grissa, Kaouthar Lebdi; Zeineb, Ghrabi-Gammar et al

in Bulletin de la Société Royale Belge d'Entomologie = Bulletin van de Koninklijke Belgische Vereniging voor Entomologie (2011), 147(I-IV), 71-79

To develop sustainable pest control in Tunisian citrus orchards, the present work aimed to evalute the toxicity of 31 plant extracts obtained from Tunisia and two synthetic acaricides (spirodiclofen and ... [more ▼]

To develop sustainable pest control in Tunisian citrus orchards, the present work aimed to evalute the toxicity of 31 plant extracts obtained from Tunisia and two synthetic acaricides (spirodiclofen and fenbutatin oxide) on the phytophagous mite species Tetranychus urticae (Koch). [less ▲]

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See detailAssessment of the Biological Effectiveness of Nasal Synthetic Salmon Calcitonin (Ssct) by Comparison with Intramuscular (I.M.) or Placebo Injection in Normal Subjects
Reginster, Jean-Yves ULg; Denis, D.; Albert, Adelin ULg et al

in Bone and Mineral (1987), 2(2), 133-40

For patients who require treatment over a period of some years, intranasal administration of synthetic salmon calcitonin (SSCT) obviates the discomfort associated with administration by injection ... [more ▼]

For patients who require treatment over a period of some years, intranasal administration of synthetic salmon calcitonin (SSCT) obviates the discomfort associated with administration by injection. Moreover, this mode of administration is not associated with the side effects normally encountered when calcitonin is injected intramuscularly or subcutaneously. The aim of this study was to assess, in normal subjects, the biological activity of nasal SSCT by comparing the fluctuations of parameters reflecting calcium-phosphorus metabolism after nasal instillation, injection of SSCT and injection of placebo, respectively. In nine healthy subjects, this instillation of 200 IU of SSCT into the nasal cavity caused a fall in serum calcium, a fall in serum phosphorus and a transient rise in parathyroid hormone levels similar to that observed after the intramuscular (i.m.) injection of 80 IU of SSCT. SSCT whether administered by the nasal route or by injection, does not inhibit endogenous calcitonin secretion. There were no changes in serum beta-endorphin, magnesium or erythrocyte magnesium levels after administration of calcitonin by the intranasal route or by injection. [less ▲]

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See detailAssessment of the cell-mediated immunity in cattle infection after bovine herpesvirus 4 infection, using an in vitro antigen-specific interferon-gamma assay.
Godfroid, J.; Czaplicki, G.; Kerkhofs, P. et al

in Veterinary Microbiology (1996), 53(1-2), 133-41

The cell-mediated immunity (CMI) following bovine herpesvirus 4 (BHV4) infection has been poorly investigated in cattle. The in vivo response measured by a delayed type of hypersensitivity (DTH) assay has ... [more ▼]

The cell-mediated immunity (CMI) following bovine herpesvirus 4 (BHV4) infection has been poorly investigated in cattle. The in vivo response measured by a delayed type of hypersensitivity (DTH) assay has been reported to be positive in only few animals showing serological evidences of BHV4 infection. We have investigated the CMI following BHV4 infection by an in vitro antigen-specific interferon gamma (IFN-gamma) release assay, as an indicator of an actively acquired immunity to BHV4. Our preliminary results using a partially purified antigen suggest that there was a measurable CMI in 75 out of 168 animals (44.4%) originating from a farm with a clinical history and serological evidences (76.3% seropositivity) of BHV4 infection. If the results of serological tests and BHV4 IFN-gamma test are interpreted in parallel, 81.5% of the animals are classified positive, demonstrating the complementarity of these tests. The specificity of the BHV4 IFN-gamma test was supported by the absence of a measurable CMI in 41 animals originating from a farm with no clinical history or serological evidence of BHV4 infection. In an allied study, we developed a bovine herpesvirus 1 (BHV1) IFN-gamma test. This allowed us to measure the antigen specific IFN-gamma release after stimulation with a mixture of BHV1 and BHV4 antigens. Animals that were classified negative by the BHV4 IFN-gamma test and by the BHV1 IFN-gamma test, were classified negative after stimulation with a mixture of both antigens. Animals that were classified positive by the BHV4 IFN-gamma test or the BHV1 IFN-gamma test, were classified positive after stimulation with a mixture of both antigens. Taken together these results suggest that the in vitro assessment of the CMI after BHV4 infection should be further investigated as a specific and valuable alternative to the DTH assay. [less ▲]

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See detailAssessment of the chemical contamination in home-produced eggs in Belgium: General overview of the CONTEGG study
Van Overmeire, Ilse; Pussemier, Luc; Wageneers, Nadia et al

in Science of the Total Environment (2009), 407(15), 4403-4410

This overview paper describes a study conducted for the Belgian Federal Public Service of Health, Food Chain Safety and Environment during 2006–2007. Home-produced eggs from Belgian private owners of hens ... [more ▼]

This overview paper describes a study conducted for the Belgian Federal Public Service of Health, Food Chain Safety and Environment during 2006–2007. Home-produced eggs from Belgian private owners of hens were included in a large study aiming to determine concentration levels of various environmental contaminants. Bymeans of the analyses of soil samples and of kitchen waste samples, obtained from the same locations, an investigation towards the possible sources of contaminants was possible. Eggs, soils, faeces and kitchen waste samples were checked for the presence of dioxins, PCBs (including dioxin-like PCBs), organochlorine pesticides, trace elements, PAHs, brominated flame retardants and mycotoxins. The study design, sampling methodology and primary conclusions of the study are given. It was found that in some cases dioxin-like compounds were present at levels that are of concern for the health of the egg consumers. Therefore, measures to limit their contamination in eggs, produced by hens of private owners, were proposed and deserve further attentio [less ▲]

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See detailAssessment of the combustion characteristics of hydrogen transverse jets in supersonic crossflow
Gamba, Mirko; Terrapon, Vincent ULg; Saghafian, Amirreza et al

in Annual Research Briefs (2011)

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See detailAssessment of the ecological status of Mediterranean French coastal waters as required by the Water Framework Directive using the Posidonia oceanica Rapid Easy Index: PREI
Gobert, Sylvie ULg; Sartoretto, Stéphane; Rico-Raimondino, Valérie et al

in Marine Pollution Bulletin (2009), 58

This paper describes the PREI (Posidonia oceanica Rapid Easy Index), a method used to assess the ecological status of seawater along Mediterranean French coasts. The PREI was drawn up according to the ... [more ▼]

This paper describes the PREI (Posidonia oceanica Rapid Easy Index), a method used to assess the ecological status of seawater along Mediterranean French coasts. The PREI was drawn up according to the requirements of the Water Framework Directive (WFD 2000/60/EC) and was tested on 24 and 18 stations in PACA (Provence-Alpes-Côtes d’Azur) and Corsica respectively. The PREI is based on five metrics: shoot density, shoot leaf surface area, E/L ratio (Epiphytic biomass/leaf biomass), depth of lower limit, and type of this lower limit. The 42 studied stations were classified in the first four levels of status: high, good, moderate and poor. The PREI values ranged between 0.280 and 0.847; this classification is in accordance with our field knowledge and with our knowledge of the literature. The PREI was validated regarding human pressure levels (r²= 0.74). (http://eurex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2000:327:0001:0072:EN:PDF) [less ▲]

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See detailAssessment of the ecological status of P. oceanica meadow with a no destructive shoot method
Gobert, Sylvie ULg; Lejeune, Pierre ULg; Chéry, Aurélia et al

in Proceedings of the Mediterranean Seagrass Workshop 2012 (2012, June)

Posidonia oceanica (L.) Delile is a protected species, included in the Red list of marine threatened species of the Mediterranean. Because of its sensitivity to disturbance, P. oceanica is used as a ... [more ▼]

Posidonia oceanica (L.) Delile is a protected species, included in the Red list of marine threatened species of the Mediterranean. Because of its sensitivity to disturbance, P. oceanica is used as a bioindicator to define the health status of coastal waters. Monitoring methods generally require to sample plants, followed by measurements on picked shoots. This implies the total destruction of several tens of shoots. This study presents a method, “The Non Destructive Shoot Methodology”: NDSM, that permits the measurement of (1) the most used seagrass metrics, (2) the determination of C, N, P contents and (3) the measurement of the trace metal levels in P. oceanica leaves. Our technic has been firstly tested by comparison with the results obtained with classic method of biometry. Secondly, differences between levels of C, N, P and trace metals obtained with classic picking and our methodology were tested. Thirdly, the physiological consequences on the shoots were investigated (% of survival, growth, essential element contents (C, N, P, Fe, Cu...). The NDSM gives similar results to classic investigations to assess the ecological status of P. oceanica meadow (i.e. PREI, BiPO...) and avoid the uprooting of the “K-strategist” protected species. This methodology is usable in cases of monitoring and impact studies. [less ▲]

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See detailAssessment of the Effect of Micro-Simulation Error on Key Travel Indices: Evidence from the Activity-Based Model FEATHERS
Cools, Mario ULg; Kochan, Bruno; Bellemans, Tom et al

in Proceedings of the 90th Annual Meeting of the Transportation Research Board (DVD-ROM) (2011)

Current transportation models often do not explicitly address the degree of uncertainty in travel forecasts. Of particular interest in activity-based travel demand models is the model uncertainty that is ... [more ▼]

Current transportation models often do not explicitly address the degree of uncertainty in travel forecasts. Of particular interest in activity-based travel demand models is the model uncertainty that is caused by the statistical distributions of random components, i.e. micro-simulation error. Therefore, the main objective of this paper is to assess the impact of micro-simulation error on two key travel indices, namely the average daily number of trips per person and the average daily distance traveled per person. The effect of micro-simulation error will be investigated by running the activity-based modeling framework FEATHERS 200 times using the same 10% fraction of the population. Results show that micro-simulation errors are limited especially when disaggregation is limited to two levels. Notwithstanding, results indicate that for more elaborate analyses a 10% fraction might not be sufficient. The size of micro-simulation error increases along with complexity. Moreover, more commonly used transport modes such as using the car as driver have a lower error rate. Further research should investigate the impact of the population fraction on the micro-simulation error rates. Besides, one could also investigate other aspects (e.g. the number of activities) involved in the activity-scheduling process. [less ▲]

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See detailAssessment of the effect of small-scale TEC gradients on DPN-GPS applications using a system of colors
Warnant, René ULg; Lejeune, Sandrine; Pottiaux, Eric

Report (2003)

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See detailAssessment of the effects of tree species diversity on forest biodiversity and ecosystem functioning (FORBIO) - Final Report
Verheyen, Kris; Carnol, Monique ULg; Branquart, Etienne et al

Report (2010)

Forests are biodiversity hotspots worldwide with 70% of terrestrial biodiversity being included in forested landscapes. However, deforestation, forest degradation and fragmentation lead to an increasing ... [more ▼]

Forests are biodiversity hotspots worldwide with 70% of terrestrial biodiversity being included in forested landscapes. However, deforestation, forest degradation and fragmentation lead to an increasing rate of species extinctions. Hence, predicting the consequences of changes in species numbers, in distribution patterns of taxa, and of shifts in dominance, has become a major challenge for community and ecosystem ecology. However, until now the relationships between biodiversity and ecosystem functioning in forests have been largely underexplored Therefore, the overall aims of the BELSPO cluster project FORBIO are: to review, synthesize and disseminate existing knowledge about the benefits and drawbacks of mixed stands vs monocultures (WP1); and to establish a highly innovative, large-scaled forest biodiversity experiment to evaluate the impact of increasing tree diversity on forest ecosystem functioning (WP2). To achieve the first objective, a so-called ‘white paper’ has been compiled by the FORBIO team members which has been published in Dutch as a special issue of the BosRevue and in French as a special issue of Forêt Wallone. Among stakeholders, many different opinions exist about the functioning of mixed forests and therefore the scientific evidence was confronted with stakeholder perceptions on ecosystem services in mixed forests compared to monocultures. The principal outcome was that stakeholders appear to have quite strong opinions on the functioning of mixed vs monoculture stands, whereas the review of the scientific literature highlighted the lack of specific information on forest ecosystem services in mixed forests compared to monocultures, in particular from studies where confounding factors can be eliminated or accounted for. The second objective was met by establishing two large-scaled tree diversity experiments in Zedelgem (Flanders) and Gedinne (Wallonia). Based on a state-of-the-art experimental design, 32 810 and 33 304 trees of five different species were planted in 42 and 44 experimental plots in Zedelgem and Gedinne, respectively. A third experiment with a similar design will be established in Hecthel-Eksel (Flanders) in 2011. FORBIO’s short-term contributions to sustainable development are mainly related to the fact that the project has introduced the state-of-the-art concepts and empirical support on the various relationships between biodiversity and ecosystem functioning to a large audience of forest owners, managers, users and scientists in Belgium. In the long-run, FORBIO will significantly contribute to a better understanding of the importance of tree species diversity for the functioning of forest ecosystems and the ecosystem services that they provide thanks to the establishment of the two (and soon three) large-scaled tree diversity experiments. Furthermore, the experiments, embedded in the worldwide TreeDivNetwork, will most likely continue to act as an attractor for researchers from Belgium and abroad. [less ▲]

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See detailAssessment of the Electric and Magnetic field levels in the vicinity of the HV overhead power lines in Belgium.
Hoeffelman, Jean; Decat, Gilbert; Lilien, Jean-Louis ULg et al

in Conférence Internationale des Grands Réseaux Electriques à Haute Tension - CIGRE (2004, August)

Maximum exposure levels in the vicinity of HV power lines in Belgium.

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See detailAssessment of the functional role of tree diversity: the multi-site FORBIO experiment
Verheyen, Kris; Ceunen, Kris; Ampoorter, Evy et al

in Plant Ecology and Evolution (2013), 146(1), 26-35

Context – During the last two decades, functional biodiversity research has provided strong support for the hypothesis that more biodiverse ecosystems have the potential to deliver more and better ... [more ▼]

Context – During the last two decades, functional biodiversity research has provided strong support for the hypothesis that more biodiverse ecosystems have the potential to deliver more and better services. However, most empirical support for this hypothesis comes from simple structured communities that are relatively easy to manipulate. The impact of forest biodiversity on forest ecosystem functioning has been far less studied. Experiment design – In this paper, we present the recently established, large-scale FORBIO experiment (FORest BIOdiversity and Ecosystem Functioning), specifically designed to test the effects of tree species diversity on forest ecosystem functioning. FORBIO’s design matches with that of the few other tree diversity experiments worldwide, but at the same time, the FORBIO experiment is unique as it consists of a similar experimental set-up at three sites in Belgium (Zedelgem, Hechtel-Eksel and Gedinne) with contrasting edaphic and climatological c haracteristics. This design will help to provide answers to one of the most interesting unresolved questions in functional biodiversity research, notably whether the effects of complementarity on ecosystem functioning decrease in less stressful and more productive environments. At each site, FORBIO consists of 41 to 44 plots (127 plots in total) planted with monocultures and mixtures up to four species, selected from a pool of five site-adapted, functionally different tree species. When allocating the treatments to the plots, we maximally avoided any possible covariation between environmental factors. Monitoring of ecosystem functioning already started at the Zedelgem and Gedinne sites and will start soon in Hechtel-Eksel. Multiple processes are being measured and as the trees grow older, we plan to add even more processes. Expected results – Not only basic science, but also forest management will benefit from the results coming from the FORBIO experiment, as FORBIO is, for instance, also a test case for uncommon, not well-known tree species mixtures. To conclude, FORBIO is an important ecosystem experiment that has the potential to deliver badly needed insights into the multiple relationships between biodiversity and ecosystem functioning, which will be valuable for both science and practice. [less ▲]

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