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See detailDerjaguin-Broekhoff-de Boer analysis of adsorption in very disordered mesopores using probabilistic models
Gommes, Cédric ULg

Poster (2015, May)

Our current ability to produce mesoporous materials with ordered morphology has raised fascinating questions about the impact of geometrical disorder on adsorption and desorption states [1]. Many recent ... [more ▼]

Our current ability to produce mesoporous materials with ordered morphology has raised fascinating questions about the impact of geometrical disorder on adsorption and desorption states [1]. Many recent works have investigated the role of mild elements of disorder, such as local constriction or corrugation superimposed to otherwise geometrically ideal cylindrical pores [2,3]. These works have notably shown that elements of disorder may act as nucleation sites and destabilize vapor-like metastable states. The relevance of these perturbation-like results to fundamentally disordered materials, such as gels, is unclear. In particular, do vapor-like metastable states exist at all in this type of very disordered material? In the present communication, we address this question using probabilistic models to investigate the role of disorder. We generalize the classical Gaussian field models of porous materials [4] and use them to analyze adsorption and desorption in the Derjaguin-Broekhof-de Boer approximation. Our approach differs from earlier contributions in that both the adsorbent and the adsorbate are described in terms of probabilities [5]. This enables us to analyze the adsorbate configuration in very disordered solids using a low-dimensional yet realistic configuration space. We notably show that vapor-like metastable states are unlikely in gel-like disordered materials. [1] D.Wallacher, N. Künzner, D. Kovalev, N. Knorr, K. Knorr, Capillary condensation in linear mesopores of different shape, Phys. Rev. Lett. 92 (2004) 195704; [2] B. Coasne, A. Galarneau, F. Di Renzo, R.M.J. Pellenq, Effect of morphological defects on gas adsorption in nanoporous silicas, J. Phys. Chem. C 111 (2007) 15759; [3] C.J. Gommes, Adsorption, capillary bridge formation, and cavitation in SBA-15 corrugated mesopores: A Derjaguin-Broekhoff-de Boer analysis, Langmuir 28 (2012) 5101-5115; [4] R.J. Pellenq, P. levitz, Capillary condensation in a disordered mesoporous medium: A grand canonical Monte Carlo study, Molecular Physics 100 (2002) 2059;[5] C.J. Gommes, A.P. Roberts, in preparation. [less ▲]

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See detailIn silico screening to predict chondrocyte hypertrophy using a semiquantitative gene network model
Kerkhofs, Johan ULg; Leijten, Jeroen; Luyten, Frank et al

Poster (2015, April 30)

PURPOSE: In development, chondrocyte hypertrophy is a crucial and well-studied step in endochondral ossification. Hypertrophy may also play a role in pathophysiological processes, including osteoarthritis ... [more ▼]

PURPOSE: In development, chondrocyte hypertrophy is a crucial and well-studied step in endochondral ossification. Hypertrophy may also play a role in pathophysiological processes, including osteoarthritis. We employ a computational approach to estimate the effect of individual factors in this complex process. METHODS: We have combined information gleaned from a high number of publications on chondrocyte differentiation into a gene regulatory network of 46 factors and over 150 interactions. This network can estimate the stability of proliferative chondrocytes/permanent cartilage (stable state with SOX9 activity) and hypertrophic chondrocytes (stable state with RUNX2 activity) by employing 2 measures. A first measure is a Monte Carlo analysis that assesses stability in the face of random initial conditions, the second modifies stable states to estimate the sensitivity to perturbation. RESULTS: For each factor, these qualitative measures are calculated in silico under knockout and overexpression conditions and compared to the wild type situation. This enables screening of the effects of all incorporated factors on cartilage homeostasis, differentiation and pathogenesis via the initiation of hypertrophy. Indeed, our gene network analysis indicated multiple candidate genes for the development of osteoarthritis. Factors that amplify the SOX9 attractor basin include TGFβ, PPR, IGF-I, and PKA. The presence of RAS, IHH, GLI2 and FGF is required for the Runx2 stable state. Using a literature study, we corroborated several of the proposed factors. CONCLUSIONS: In silico screening of overexpression and knockout presents a novel strategy to improve bone and cartilage tissue engineering approaches, and can be used to propose a list of putative therapeutic targets for e.g. osteoarthritis. [less ▲]

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See detailEpidemiological aspects and genotypic characterization of strains of Microsporum audouinii isolated in the context of a Belgian National survey on anthropophilic tinea
SACHELI, Rosalie ULg; Géron, Bénédicte; Dekkers, Charlotte et al

Poster (2015, April 28)

Objectives The last two years, clinical cases of tinea capitis caused by Microsporum audouinii (M. audouinii), have increased in Belgium. To better understand the emergence of this species in the ... [more ▼]

Objectives The last two years, clinical cases of tinea capitis caused by Microsporum audouinii (M. audouinii), have increased in Belgium. To better understand the emergence of this species in the population, the Belgian National Reference Center (NRC) for dermatophytes launched a national survey in 2013. Epidemiological aspects and genotypic characterization of the strains were included. Methods The study was conducted from March 2013 up to February 2014. All Belgian laboratories were asked to send M. audouinii strains isolated from hair to the NRC with a form to fill in including epidemiological informations. The fungal strains were identified by microscopy or ITS sequencing in case of doubt. The genotypic analysis was performed by the DiversiLab® system (bioMérieux) for DNA fingerprinting and analysis. Epidemiological informations were analyzed with the help of a biostatistician. Results Among the collected isolates, 97 strains have been currently confirmed as M. audouinii. Preliminary analysis of the epidemiological characteristics of the infected population shows that the main age category concerns 5-9 year-old children (84%) with a sex-ratio M/F of 1.95. Data concerning the geographic origin of the family have been obtained in only 45.8% of the cases. It reveals that strains have been mainly isolated from patients with a Belgian nationality (77%) suggesting bias in the data collection. The geographic origin of the remaining group (23%) includes several African countries. The genotypic analysis led to the distinction of 3 genotypic variants of M. audouinii. One of these variants was exclusively recovered from South Belgium (11 strains). The major group was composed of 85 strains, well distributed in different Belgium locations. The last group contains only one strain but this strain was significantly different from the two other variants. Conclusion The automated typing DiversiLab® system proved to be an easy and efficient method to investigate the molecular epidemiology of dermatophytes infections. These preliminary results show that, through Belgium, several groups of isolates co-exist for M. audouinii providing evidence of genetic heterogeneity. At this time all epidemiological informations have not yet been assessed while 35 strains of M. audouinii remain to be analysed genotypically to give definitive conclusions. [less ▲]

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See detailEpidemiology and clinical reporting of candidaemia in Belgium : a national prospective study (TANSIR trial)
Trouvé, Charlotte; Blot, Stijn; Hayette, Marie-Pierre ULg et al

Poster (2015, April 26)

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See detailEvaluation of a commercially developed semi-automated PCR-surface enhanced raman scattering assay for the detection of Candida species in blood
HAYETTE, Marie-Pierre ULg; WERY, Marie ULg; BOREUX, Raphaël ULg et al

Poster (2015, April 25)

Objectives Microbiological diagnosis of invasive candidiasis is still dependent on culture-based methods. The use of beta-D-glucan antigen detection is included in the EORTC microbiological diagnostic ... [more ▼]

Objectives Microbiological diagnosis of invasive candidiasis is still dependent on culture-based methods. The use of beta-D-glucan antigen detection is included in the EORTC microbiological diagnostic criteria but is rarely available in the clinical labs. On the other hand, PCR-based methods lack standardization. The RenDx Fungiplex® is a new commercially available semi-automated PCR SERS assay designed for the detection of Aspergillus sp. and Candida sp. including the differentiation of resistant strains as C. glabrata, C. krusei and A. terreus. This study was performed for sensitivity and reproducibility testing of the method on 8 different Candida species. Methods The study was conducted on EDTA-blood collected from a healthy donor. Blood samples were spiked with 10 Candida reference strains: C. albicans ATCC 10231, C. albicans NEQAS 1206 and C. albicans NEQAS 2359; C. glabrata ATCC 90030 ; C. krusei ATCC 6258 ; C. tropicalis NEQAS 1036 ; C. guillermondii NEQAS 1035 ; C. parapsilosis ATCC 22019 ; C. lusitaniae NEQAS 1511 and C. dubliniensis IHEM 14280. Spiked samples were diluted at final concentrations ranging from 1 CFU/mL to 1000 CFU/mL. Cultures on Sabouraud dextrose agar were performed in parallel to control yeasts dilutions. DNA extraction was performed by using proteinase K-based method followed by purification on QIAcube automate. The RenDx Fungiplex®kit (Renishaw) was used for the amplification process and the final detection was processed on the SP-1000 sample analyzer. Reproducibility testing was performed on the three C. albicans reference strains by repeating each test 5 times. Results A total of 142 samples were included in the study. A sensitivity of 10 CFU/mL was reached for C. glabrata, C. krusei, C. tropicalis, C. dubliniensis spiked samples while C. lusitaniae and C. tropicalis performed better at 1 CFU/mL. The three tested reference C. albicans strains and C. guillermondii gave the lowest sensitivity (100 CFU/mL). The reproducibility of the assay was 96% Conclusion RenDx Fungiplex®kit allows the detection of the most frequent Candida species responsible for invasive candidiasis in spiked blood samples. The sensitivity of the test is comprised between 10 and 100 CFU/mL for most Candida sp. and reproducibility is very high. This evaluation allows us to consider this commercial kit for inclusion in a clinical study on invasive candidiasis in comparison with non-molecular diagnostic assays. [less ▲]

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See detailStudy of a new splice variant of Neuropilin-1: antagonistic functions in the regulation of cancer progression?
Hendricks, Céline ULg; Janssen, Lauriane; Delcombel, Romain et al

Poster (2015, April 22)

Neuropilin-1 (NRP1) is a transmembrane glycoprotein and a co-receptor for several growth factors, for example some variants of the Vascular Endothelial Growth Factor A (VEGF-A). It largely contributes to ... [more ▼]

Neuropilin-1 (NRP1) is a transmembrane glycoprotein and a co-receptor for several growth factors, for example some variants of the Vascular Endothelial Growth Factor A (VEGF-A). It largely contributes to the regulation of angiogenesis but also to cancer formation. NRP1 can be considered as a proteoglycan as glycosaminoglycans side chains can be added on serine 612. Currently, six splice variants of NRP1 have been described. An additional form was recently identified in our laboratory. Depending upon the cell types, it represents 20-30% of the total amount of NRP1. As compared to the full size NRP1 (NRP1-FS), 7 amino acids are deleted. As the missing sequence is located 2 amino acids downstream of the Ser612 required for glycosaminoglycans addition, this process could be somehow affected and the function of the protein could be modified. The glycosylation of NRP1-FS and -Δ7 was analyzed in different cells overexpressing each isoform. Western blotting analyses suggested that NRP1-Δ7 was less glycosylated than NRP1-FS. Prostate cancer cells (PC3) were engineered to express NRP1-FS or –Δ7 only in the presence of doxycycline. The migration of these cells was analyzed by scratch assay, with or without doxycycline in the medium. As compared to controls and to NRP1-FS-expressing cells, production of NRP1-Δ7 was linked to a reduction of cell migration. A DNA dosage showed that NRP1-FS enhanced cell proliferation, while NRP1-Δ7 reduced it. Tumor growth was assessed in vitro by a culture in soft agar. As compared to control conditions, expression of NRP1-FS by doxycycline increased colonies formation. By contrast, NRP1-Δ7 inhibited colonies number, suggesting an inhibition of tumorigenesis by this variant. As PC3 cells express basal level of endogenous NRP1, this suggests some competitive inhibition of NRP1 functions by NRP1-Δ7. Finally, the function of each variant was investigated in vivo in a model of injection in the flanks of nude mice of PC3 cells conditionally expressing NRP1-FS or -Δ7. As compared to the control, NRP1-FS increased tumor size and weight. By sharp contrast, the expression of NRP1-Δ7 was associated with a reduction of tumorigenicity. Cells with forced expression of NRP1-Δ7 also developed fewer blood vessels as compared to the control. These results suggest that NRP1-Δ7 have an antagonistic action on cancer formation and angiogenesis. [less ▲]

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See detailHeat survival of Clostridium difficile spores in ground meat during cooking process
Rodriguez Diaz, Cristina ULg

Poster (2015, April 21)

Introduction: Clostridium difficile is a spore-forming pathogen considered as a major cause of enteric disease in humans, with faecal-oral route as the primary mode of transmission. However, recent ... [more ▼]

Introduction: Clostridium difficile is a spore-forming pathogen considered as a major cause of enteric disease in humans, with faecal-oral route as the primary mode of transmission. However, recent studies have reported the occurrence of C. difficile in ground meats at retail stores, indicating that foods could be an additional source of infection in the community. Purpose: The objective of this study was to determine the resistance of C. difficile spores in contaminated ground meat during cooking process. Methods: Prior to testing, to obtain spores and to enhance heterogeneity, spores of two different strains were produced in two nutritious broths. C. difficile spores were experimentally inoculated in 45 g of ground meat (beef and pork) in order to obtain a final contamination of 4,500 ufc g-1. Six heating temperatures (70, 75, 80, 85, 90 and 95°C) were chosen. Samples were heating in a water bath with an integrated program for time-temperature. One sample without inoculum was used as control with a temperature probe placed inside. Once the desired temperature was research in the core of the sample, the heat treatment was prolonged for 10 min. Subsequently, all the samples were placed on the chilling room (4°C) before analyse. These experiments were conducted in duplicate with a spore enumeration in triplicate. Results: Heating contaminated ground meat at 70, 75 and 80°C for 10 min was not effective for C. difficile spores inhibition. However, 10 min of heat shock at 80°C was the only temperature that significantly reduced the number of countable colonies. Heat treatment at 85°C (or more) inhibits the germination of both of the strains tested. Significance: Ensure that ground meat, like burgers or sausages, is heated to more than 85°C would be an important measure to reduce the risk of C. difficile food transmission. [less ▲]

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See detailSedimentary impacts of recent moderate earthquakes in different settings in the Western Gulf of Corinth, Greece
Beckers, Arnaud ULg; Mortier, Clément; Beck, Christian et al

Poster (2015, April 21)

11 short gravity cores retrieved in the Western Gulf of Corinth, Greece, allowed identifying event deposits whose age ranges were compared to an updated earthquakes catalogue for the area. 210Pb-derived ... [more ▼]

11 short gravity cores retrieved in the Western Gulf of Corinth, Greece, allowed identifying event deposits whose age ranges were compared to an updated earthquakes catalogue for the area. 210Pb-derived age-depth curves show that the majority of the event deposits may have been triggered by earthquakes. These results show that moderate earthquakes (Mw ~6.0-6.5) may significantly impact different marine settings, from shallow shelves (70-100 m deep) to the basin floor (330 m deep). The deepest coring sites show the best possible record, but one major earthquake is missing and the age of one event deposit does not fit with any known earthquake. More cores are needed to check the spatial extent of each deposit and to validate the absence of record of some earthquakes, like the 1995 Aigion earthquake. [less ▲]

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See detailLiposomes entrapping apigenin for the treatment of glioblastoma
Karim, Reatul ULg; Palazzo, Claudio ULg; Dubois, Nadège ULg et al

Poster (2015, April 17)

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See detailGlobal, diffuse and direct irradiances modelling over northwestern Europe using regional climate model MAR : validation and construction of a 30-year climatology
Beaumet, Julien ULg; Doutreloup, Sébastien ULg; Fettweis, Xavier ULg et al

Poster (2015, April 17)

Incoming solar global irradiances are modelled using MAR regional climate model forced by ERA-Interim reanalysis. Global irradiances are decomposed into direct and diffuse using sigmoid model from Ruiz ... [more ▼]

Incoming solar global irradiances are modelled using MAR regional climate model forced by ERA-Interim reanalysis. Global irradiances are decomposed into direct and diffuse using sigmoid model from Ruiz-Arias et al. (2010). Results are validated using data from the European Solar Radiation Atlas for Uccle and Braunschweig weather stations. A 30-year climatology has been built and trends and variability have been analyzed. [less ▲]

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See detailGenetic correlations between methane production and milk fatty acid contents of Walloon Holstein cattle throughout the lactation
Vanrobays, Marie-Laure ULg; Vandenplas, Jérémie ULg; Bastin, Catherine ULg et al

Poster (2015, April 16)

Methane (CH4) from ruminal fermentation is the major greenhouse gas produced by dairy cattle which contributes largely to climate change. Production of CH4 also represents losses of gross energy intake ... [more ▼]

Methane (CH4) from ruminal fermentation is the major greenhouse gas produced by dairy cattle which contributes largely to climate change. Production of CH4 also represents losses of gross energy intake. Therefore, there is a growing interest in mitigating these emissions. Acetate and butyrate have common bio-chemical pathways with CH4. Because some milk fatty acids (FA) arise from acetate and butyrate, milk FA are often considered as potential predictors of CH4. However, relationships between these traits remain unclear. Moreover, the evolution of the phenotypic and genetic correlations of CH4 and milk FA across days in milk (DIM) has not been evaluated. The main goal of this study was to estimate genetic correlations between CH4 and milk FA contents throughout the lactation. Calibration equations predicting daily CH4 production (g/d) and milk FA contents (g/100 dL of milk) from milk mid-infrared (MIR) spectra were applied on MIR spectra related to Walloon milk recording. Data included 243,260 test-day records (between 5 and 365 DIM) from 33,850 first-parity Holstein cows collected in 630 herds. Pedigree included 109,975 animals. Bivariate (i.e., CH4 production and one of the FA traits) random regression test-day models were used to estimate genetic parameters of CH4 production and 7 groups of FA contents in milk. Saturated (SFA), short-chain (SCFA), and medium-chain FA (MCFA) showed positive averaged daily genetic correlations with CH4 production (from 0.25 to 0.29). Throughout the lactation, genetic correlations between SCFA and CH4 were low in the beginning of the lactation (0.11 at 5 DIM) and higher at the end of the lactation (0.54 at 365 DIM). Regarding SFA and MCFA, genetic correlations between these groups of FA and CH4 were more stable during the lactation with a slight increase (from 0.23 to 0.31 for SFA and from 0.23 to 0.29 for MCFA, at 5 and 365 DIM respectively). Furthermore, averaged daily genetic correlations between CH4 production and monounsaturated (MUFA), polyunsaturated (PUFA), unsaturated (UFA), and long-chain FA (LCFA) were low (from 0.00 to 0.15). However, these genetic correlations varied across DIM. Genetic correlations between CH4 and MUFA, PUFA, UFA, and LCFA were negative in early lactation (from -0.24 to -0.34 at 5 DIM) and increased afterward to become positive from 15 weeks till the end of the lactation (from 0.14 to 0.25 at 365 DIM). Finally, these results indicate that genetic and, therefore, phenotypic correlations between CH4 production and milk FA vary following lactation stage of the cow, a fact still often ignored when trying to predict CH4 production from FA composition. [less ▲]

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See detailCorrelation between levels of β-hydroxybutyrate and fatty acids in blood and milk and its impact on ketosis diagnosis in dairy cows
Lessire, Françoise ULg; Knapp, Emilie ULg; Dotreppe, Olivier et al

Poster (2015, April 16)

SKC at herd level is difficult to diagnose. Poor production and reproduction performances are usually observed as an increased incidence of periparturient diseases in the herd (Suthar et al., 2013 ... [more ▼]

SKC at herd level is difficult to diagnose. Poor production and reproduction performances are usually observed as an increased incidence of periparturient diseases in the herd (Suthar et al., 2013). Diagnosis methods include determination of beta-hydroxybutyrate (BHB) and increased non-esterified fatty acids (NEFA) resulting from body fat mobilization. BHB and NEFA could be dosed in blood of animals in late gestation and in early lactation. Post calving, cows presenting BHB over 1. 2-1.4 mmol/L are considered SCK-cows while those presenting NEFA over 0.6 mg/L are labelled fat mobilising cows. Development of non-invasive diagnosis techniques could be interesting to sample animals at a larger scale with lesser stress. The aim of this study was to verify whether blood and milk BHB values were correlated and whether diagnostic methods by milk analysis could be developed. Seventy -five cows out of 8 selected Walloon dairy herds were followed up monthly from calving to pregnancy diagnosis regarding production and reproduction. At each visit (V), BHB and NEFA levels were determined in milk and blood. A maximum of 5 V was made. BHB was determined in blood using a cow-side test and in milk by a colorimetric test . Blood NEFA and milk fatty acids were determined by gas chromatography (GC). Statistical analysis was performed by SAS 9.1. BHB levels in blood and milk were highly correlated (r= 0.86), indicating the possibility of diagnosis of SCK by milk sampling. The earliest the samples have been taken, the better the correlation is (r=0.95 V1; r = 0.91 V2). Comparison of BHB with NEFA demonstrated a better correlation with milk BHB than with blood BHB (respectively 0.51 and 0.53 in milk vs 0.41 and 0.48 in blood for the V1 and V2 respectively). After the 2d V, the correlation dropped to 0.38 (V3) and -0.14 (V4).To conclude, dosage of milk BHB could be a good indicator for ketosis diagnosis taking into account that correlation with blood BHB and with NEFA is time-related. [less ▲]

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See detailEvaluation of soil structural changes through macroscopic and microscopic measurement
Parvin, Nargish ULg; Degré, Aurore ULg; Chelin, Marie ULg et al

Poster (2015, April 16)

The heterogeneity of soil structure and pore size distribution are highly influenced by external factors like tillage systems and other agricultural management practices. However, changes in soil ... [more ▼]

The heterogeneity of soil structure and pore size distribution are highly influenced by external factors like tillage systems and other agricultural management practices. However, changes in soil hydrodynamic behavior are not fully understood and are still under research. Also, researchers have explained the impact of tillage practices on soil hydraulic properties related to pore size distribution, connectivity and orientation are involved but the characterization of these modifications and consequences remains a challenge. Furthermore, the relation between macroscopic measurements and microscopic investigation of the soil structure remains scarce. Recently, X-ray tomography (X- μCT) has been used in order to characterize changes in soil pore size distribution in various contexts and the method is able to link microtomography information to hydrodynamic measurement. In our study, X-μCT has been used in order to characterize changes in soil pore system. Since, tomography does not count most of the micropores, Richards’ pressure plate and evaporation method was also combined to get complete range of pore size distribution. We found good match between evaporation data with X-μCT at the macropore scale and evaporation data with pressure plate method at micropore scale. X-μCT data refines retention and hydraulic curves near saturation where Richards’ data alone can lead to numerous sets of fitted parameters. On the otherhand, evaporation data (Hyprop apparatus ©) provide comparable datasets with X-μCT. Combining micro and macroscopic measurements allows us to validate X-μCT information, which is otherwise not so obvious. [less ▲]

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See detailVariogram-based inversion of time-lapse electrical resistivity data: development and application to a thermal tracing experiment
Hermans, Thomas ULg; Nguyen, Frédéric ULg

Poster (2015, April 15)

Electrical resistivity tomography (ERT) has become a popular imaging methodology in a broad range of applications given its large sensitivity to subsurface parameters and its relative simplicity to ... [more ▼]

Electrical resistivity tomography (ERT) has become a popular imaging methodology in a broad range of applications given its large sensitivity to subsurface parameters and its relative simplicity to implement. More particularly, time-lapse ERT is now increasingly used for monitoring purposes in many contexts such as water content, permafrost, landslide, seawater intrusion, solute transport or heat transport experiments. Specific inversion schemes have been developed for time-lapse data sets. However, in contrast with static inversions for which many techniques including geostatistical, minimum support or structural inversion are commonly applied, most of the methodologies for time-lapse inversion still rely on non-physically based spatial and/or temporal smoothing of the parameters or parameter changes. In this work, we propose a time-lapse ERT inversion scheme based on the difference inversion scheme. We replace the standard smoothness-constraint regularization operator by the parameter change covariance matrix. This operator takes into account the correlation between changes in resistivity at different locations through a variogram computed using independent data (e.g., electromagnetic logs). It may vary for subsequent time-steps if the correlation length is time-dependent. The methodology is first validated and compared to the standard smoothness-constraint inversion using a synthetic benchmark simulating the injection of a conductive tracer into a homogeneous aquifer inducing changes in resistivity values of known correlation length. We analyze the influence of the assumed correlation length on inversion results. Globally, the method yields better results than the traditional smoothness constraint inversion. Even if a wrong correlation length is assumed, the method performs as well as the smoothness constraint since the regularization operator balances the weight given to the model constraint functional in the objective function. Then the methodology is successfully applied to a heat injection and pumping experiment in an alluvial aquifer. The comparison with direct measurements in boreholes (temperature loggers and distributed temperature sensing optic fibres) shows that ERT-derived temperatures and breakthrough curves image reliably the heat plume through time (increasing part of the curve, maximum and tail are correctly retrieved) and space (lateral variations of temperature are observed) with less spatial smoothing than standard methods. The development of new regularization operators for time-lapse inversion of ERT data is necessary given the broad range of applications where ERT monitoring is used. In many studies, independent data are available to derive geostatistical parameters that can be subsequently used to regularize geophysical inversions. In the future, the integration of spatio-temporal variograms into existing 4D inversion schemes should further improve ERT time-lapse imaging. [less ▲]

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See detailExperimental design to monitor the influence of crop residue management on the dynamics of soil water content
Chelin, Marie ULg; Parvin, Nargish ULg; Hiel, Marie-Pierre ULg et al

Poster (2015, April 15)

Choices related to crop residue management affecting soil structure determine spatio-temporal dynamics of water content and eventually crop yields. In this contribution, we discuss the experimental design ... [more ▼]

Choices related to crop residue management affecting soil structure determine spatio-temporal dynamics of water content and eventually crop yields. In this contribution, we discuss the experimental design we adopted to study the influence of three different agricultural management strategies (tillage and residue management) on the soil water dynamics under maize in a Cutanic Siltic Luvisol in Gembloux, Belgium. In order to limit soil disturbance, we opted for the use electrical resistivity tomography (ERT) and we use the bulk electrical conductivity as a proxy for soil moisture content. ERT is collected every week on a surface of two square meters corresponding to three rows of seven maize plants through surface stainless steel electrodes. Four additional sticks with stainless steel electrodes will be vertically inserted into the soil up to 1.20 m to get more detailed information near to the central maize row. In each of the monitoring plots, two time-domain reflectometry (TDR) probes will be installed for data validation. In order to calibrate the relationship between electrical resistivity and soil water content under highly variable field conditions (changes in soil structure, variable weather conditions, plant growth, fertilization), a trench will be dug, in which a set of four electrodes, one TDR probe and one temperature sensor will be placed at four different depths. In addition, two suction cups will be installed in each of the plots to quantify changes in ion composition and electrical conductivity of the soil solution at two different depths. Within the framework of the multidisciplinary research platform AgricultureIsLife, regular assessment of pore structure and crop developement will be conducted using X-ray images. Combining this wide range of data, we will be able to investigate and quantify the effect of simultaneously changing pore water conductivity, soil porosity, soil temperature and soil moisture on the effectiveness of time-lapse ER measurements as a proxy for soil moisture changes. [less ▲]

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See detailThe seamod.ro operational stochasting forecasting system of the Black Sea
Vandenbulcke, Luc ULg; Barth, Alexander ULg; Capet, Arthur et al

Poster (2015, April 15)

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See detailRegularized focusing inversion of time-lapse electrical resistivity data: an approach to parametrize the minimum gradient support functional
Nguyen, Frédéric ULg; Hermans, Thomas ULg

Poster (2015, April 15)

Inversion of time-lapse resistivity data allows obtaining ‘snapshots’ of changes occurring in monitored systems for applications such as aquifer storage, geothermal heat exchange, site remediation or ... [more ▼]

Inversion of time-lapse resistivity data allows obtaining ‘snapshots’ of changes occurring in monitored systems for applications such as aquifer storage, geothermal heat exchange, site remediation or tracer tests. Based on these snapshots, one can infer qualitative information on the location and morphology of changes occurring in the subsurface but also quantitative estimates on the degree of changes in certain property such as temperature or total dissolved solid content. Analysis of these changes can provide direct insight into flow and transport and associated processes and controlling parameters. However, the reliability of the analysis is dependent on survey geometry, measurement schemes, data error, and regularization. Survey design parameters may be optimized prior to the monitoring survey. Regularization, on the other hand, may be chosen depending on available information collected during the monitoring. Common approaches consider smoothing model changes both in space and time but it is often needed to obtain a sharp temporal anomaly, for example in fractured aquifers. We here propose to use the alternative regularization approach based on minimum gradient support (MGS) (Zhdanov, 2002) for time-lapse surveys which will focus the changes in tomograms snapshots. MGS will limit the occurrences of changes in electrical resistivity but will also restrict the variations of these changes inside the different zones. A common difficulty encountered by practitioners in this type of regularization is the choice of an additional parameter, the so-called , required to define the MGS functional. To the best of our knowledge, there is no commonly accepted or standard methodology to optimize the MGS parameter . The inversion algorithm used in this study is CRTomo (Kemna 2000). It uses a Gauss-Newton scheme to iteratively minimize an objective function which consists of a data misfit functional and a model constraint functional. A univariate line search is performed at each Gauss-Newton iteration step to find the optimum value of the regularization parameter  which minimizes the data misfit as a function of  while the data misfit is above the desired value and yields the desired target misfit (root-mean square value of error-weighted data misfit equal to 1) at the last iteration for a maximum value of . We propose here to optimize the  of the MGS functional by considering a univariate line search at the first iteration to find the  that minimizes the data misfit. The parameter is then kept constant during the Gauss-Newton iterative scheme. In this contribution, we validate our approach on a numerical benchmark and apply it successfully on a case study in the context of salt tracers in fractured aquifers. Zhdanov M.S. 2002. Geophysical Inverse Theory and Regularization Problems. Elsevier, Amsterdam, 628 p. Kemna A. 2000. Tomographic Inversion of Complex Resistivity - Theory and Application. PhD Thesis, Ruhr University Bochum. [less ▲]

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See detailFuture projections of the Greenland ice sheet mass balance using the regional climate MAR model coupled with the GRISLI ice sheet model
Wyard, Coraline ULg; Fettweis, Xavier ULg; Ritz, Catherine

Poster (2015, April 14)

During the two last decades, the Greenland ice sheet (GrIS) contribution to the global mean sea level rise has significantly increased. But, difficulties remain to assess GrIS future contribution because ... [more ▼]

During the two last decades, the Greenland ice sheet (GrIS) contribution to the global mean sea level rise has significantly increased. But, difficulties remain to assess GrIS future contribution because of large uncertainties linked to the feedback between the surface mass balance (SMB) and GrIS topography changes. The regional climate MAR model has been coupled with the GRISLI ice sheet model, in order to account of this feedback in the future projections. The aim of this study is to assess the pertinence of the MAR-GRISLI coupling which requires long computation time. In order to identify GRISLI sensitivity to MAR forcing, GRISLI has been forced with various non-coupled (i.e. using a fixed topography), coupled and modified non-coupled MAR outputs. To adapt the non-coupled MAR outputs to the GRISLI topography changes, we use an interpolation technique based on SMB vs elevation vertical gradient. These experiences evaluate the performances/limits of this interpolation technique used to avoid a RCM-ice sheet model coupling. [less ▲]

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See detailOptical Study of a Spectrum Splitting Solar Concentrator based on a Combination of a Diffraction Grating and a Fresnel Lens
Michel, Céline ULg; Loicq, Jerôme ULg; Thibert, Tanguy ULg et al

Poster (2015, April 14)

This poster presents recent improvements of our new solar concentrator design for space application. The concentrator is based on a combination of a diffraction grating (blazed or lamellar) coupled with a ... [more ▼]

This poster presents recent improvements of our new solar concentrator design for space application. The concentrator is based on a combination of a diffraction grating (blazed or lamellar) coupled with a Fresnel lens. Thanks to this diffractive/refractive combination, this optical element splits spatially and spectrally the light and focus approximately respectively visible light and IR light onto electrically independent specific cells. It avoid the use of MJs cells and then also their limitations like current matching and lattice matching conditions, leading theoretically to a more tolerant system. The concept is reminded, with recent optimizations, ideal and more realistic results, and the description of an experimental realization highlighting the feasibility of the concept, and the closeness of theoretical and experimental results. [less ▲]

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See detailLIPOSOME CONTAINING ESTETROL FOR THE TREATMENT OF ISCHEMIA DISEASES IN PREMATURE BABIES
Palazzo, Claudio ULg; Karim, Reatul ULg; Mawet, Mawet et al

Poster (2015, April 14)

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See detailUse of NIR Hyperspectral Imaging and dichotomist classification tree based on SVM in order to discriminate roots and crop residues of winter wheat
Eylenbosch, Damien ULg; Fernández Pierna, Juan Antonio; Baeten, Vincent et al

Poster (2015, April 14)

NIR Hyperspectral Imaging coupled with SVM chemometric tool is proposed as an alternative method to the tedious and time-consuming hand sorting step needed before root quantification using the soil coring ... [more ▼]

NIR Hyperspectral Imaging coupled with SVM chemometric tool is proposed as an alternative method to the tedious and time-consuming hand sorting step needed before root quantification using the soil coring method. This method was applied to quantify roots under a winter wheat crop. [less ▲]

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See detailSoil porosity in agricultural context: A review of measurement techniques at various scales
Garré, Sarah ULg; Chelin, Marie ULg; Luong, Jeanne ULg et al

Poster (2015, April 13)

Soil compaction was identified by European Commission as one of the eight main threats for agricultural soils. In order to address this issue, measurements of soil porosity are critical. However, there ... [more ▼]

Soil compaction was identified by European Commission as one of the eight main threats for agricultural soils. In order to address this issue, measurements of soil porosity are critical. However, there are as many techniques to measure as there are definitions of porosity. A single method is not sufficient to obtain a complete image of the soil porosity at various scales and encompassing different levels of complexity. Each existing method is characterized by a unique combination of a specific level of complexity, resolution and scale of measurement. In this review, we started by defining the basic terms linked to soil porosity in an agricultural context. Then we give an overview of relevant measurement techniques, from classical methods to recent advances. We present their advantages and disadvantages, the scales of measurement, the resolution, the expected accuracy and the susceptibility to errors. This work aims at guiding the choice for the best (combination of) technique(s) to answer questions related to agricultural soil porosity, categorizing techniques according to the parameters they focus on: from total porosity over pore size distribution, structure and connectivity up to the quantification of spatio-temporal dynamics. [less ▲]

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See detailPreliminary results for a hydrogen maser cavity in the TE111 mode
Van Der Beken, Emeline ULg; Léonard, Daniel; Counet, Arnaud et al

Poster (2015, April 13)

An analysis of a hydrogen maser working with an unusual TE111 mode is presented. Different simulations have been carried out and are compared with preliminary results obtained for such a maser. In ... [more ▼]

An analysis of a hydrogen maser working with an unusual TE111 mode is presented. Different simulations have been carried out and are compared with preliminary results obtained for such a maser. In contrast to standard hydrogen maser that exploits the TE011 mode, the TE111 mode allows one to design hydrogen masers with significant reduced dimensions which represents a huge benefit for space applications and in particular for the global positioning system. [less ▲]

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See detailOrganic and inorganic carbon fluxes in a tropical river system (Tana River, Kenya) during contrasting wet seasons
Geeraert, N; Omengo, FO; Bouillon, S et al

Poster (2015, April 12)

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See detailStone tool hafting and use in the European Upper Palaeolithic: first results from Hohle Fels
Taipale, Noora ULg; Rots, Veerle ULg

Poster (2015, April 07)

European Upper Palaeolithic lithic assemblages have been so far defined largely on a typological or technological basis, whereas extensive studies that would utilise the full potential of functional ... [more ▼]

European Upper Palaeolithic lithic assemblages have been so far defined largely on a typological or technological basis, whereas extensive studies that would utilise the full potential of functional analysis have been few. In this poster, I will present the outline and first results of an ongoing PhD project dedicated to the variability in stone tool use and hafting in the Upper Palaeolithic of Central and Western Europe. Recent methodological developments have made possible the distinction between hafted and hand-held tools and the identification of different hafting modes in archaeological assemblages. The aim of my research is to understand the main developments and regional patterns in tool hafting and use in the Gravettian and Magdalenian, and evaluate their impact on lithic assemblage variability. The cave site Hohle Fels serves here as a case study, and the first results of the analysis of the site’s Gravettian material will be used to illustrate the potential of this kind of approach in the study of past human behaviour, cognition and culture. [less ▲]

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See detailMultitasking abilities in persons diagnosed with schizophrenia: a new tool and cognitive model.
Laloyaux, Julien ULg; Van der Linden, Martial ULg; Laroi, Frank ULg

Poster (2015, April 01)

Difficulties in everyday life activities are core features of persons diagnosed with schizophrenia, and in particular during multitasking activities (Semkovska et al., 2010). Multitasking refers to ... [more ▼]

Difficulties in everyday life activities are core features of persons diagnosed with schizophrenia, and in particular during multitasking activities (Semkovska et al., 2010). Multitasking refers to activities (e.g. preparing a meal) where the person has to: (a) carry out and alternate between different tasks that vary in terms of priority, difficulty and duration; (b) define the tasks’ targets; (c) and where the person is faced with unexpected problems during the realization of these tasks (Burgess, 2000). However, the cognitive underpinnings of multitasking abilities have never been adequately explored in schizophrenia. Further, only two cognitive models exist in the literature, which are based on student (Logie et al., 2011) and neurological (Burgess et al., 2000) samples. Both of these models suggest three primary constructs: Memory, Planning and Intent. There are, however, several limitations related to the way multitasking abilities were evaluated in these studies. We thus developed a computerized real-life activity task - the Computerized Meeting Preparation Task (CPMT), which was specifically designed to take into account the multitasking nature of certain everyday life activities. Using this task, and based on previous studies (Burgess et al., 2000; Logie et al., 2011), the aim of the present study was to evaluate multitasking abilities in schizophrenia and to do so in a new cognitive model of multitasking that takes into account certain cognitive functions that are not integrated in existing models. Methods: Fifty-seven individuals with schizophrenia and 41 matched healthy controls completed the CMPT. Participants were also evaluated with a battery of cognitive tests. Results: The results suggest that the CMPT possesses good sensitivity and confirmed the three underlying constructs of multitasking (Memory, Planning and Intent), which were found to be underpinned by several cognitive functions and multitasking aspects. Conclusion: Taken together, this new cognitive model and the CMPT could be a good basis for cognitive interventions of multitasking abilities in schizophrenia. Burgess, P.W., 2000. Strategy application disorder: the role of the frontal lobes in human multitasking. Psychol Res 63, 279-288. Logie, R., et al., 2011. Multitasking: multiple, domain-specific cognitive functions in a virtual environment. Mem Cogn 39, 1561-1574. Semkovska, M. et al., 2004. Assessment of executive dysfunction during activities of daily living in schizophrenia. Schizophr Res 69, 289-300. [less ▲]

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See detailAssociation of classical microbiology and 16S rDNA metagenetic Aanalysis to evaluate the presence of Clostridium difficile ina a belgian nursing home
Rodriguez Diaz, Cristina ULg; Taminiau, Bernard ULg; Avesani, Véronique et al

Poster (2015, April 01)

Increasing age, several co-morbidities, environmental contamination, antibiotic exposure and other intestinal perturbations appear to be the greatest risk factors for C. difficile infection (CDI ... [more ▼]

Increasing age, several co-morbidities, environmental contamination, antibiotic exposure and other intestinal perturbations appear to be the greatest risk factors for C. difficile infection (CDI). Therefore, elderly care home residents are considered particularly vulnerable to CDI. The main objective of this study was to evaluate and follow the prevalence of C. difficile in a Belgian nursing home. During a 4-month period, stool samples from a group of 23 elderly care home residents were collected weekly. A C. difficile microbiological detection scheme was performed along with an overall microbial biodiversity study of the faeces content by Targeted Metagenomic analysis. Culture of samples was performed in a selective medium cycloserine cefoxitin fructose cholate. An identification of the isolated colonies was done by PCR detection of tpi, tcdA, tcdB and cdtA genes. Toxic activity was confirmed by a cytotoxic immunoassay. Further characterization was performed by PCR ribotyping. The Metagenomic analysis was targeted on the v1-v3 hyper-variable region of 16S rDNA. The taxonomical assignment of the populations was performed with MOTHUR and Blast algorithms. Seven out of 23 (30.4%) residents were (at least one week) positive for C. difficile. The most common PCR-ribotype identified was 027. Targeted Metagenomic analyses reveals that each resident has his own bacterial imprint, which is stable during the entire study. Residents’ positives for C. difficile by classical microbiology showed an important proportion of C. difficile sequences. However, Metagenomics analysis can’t substitute targeted protocols. It was not used as a diagnostic tool to detect C. difficile but rather to determine the identification and correlations of the major bacterial populations that are present in the gut microbiota. In conclusion, this unique association of classical microbiology protocol with pyrosequencing allowed to follow C. difficile in patients and to identify several other bacterial populations whose abundance is correlated with C. difficile. [less ▲]

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See detailDecrease of the Black Sea Oxygen Inventory through the second half of the XXth century
capet, arthur; stanev, Emil; Grégoire, Marilaure ULg

Poster (2015, April)

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See detailSoil microbial community composition changes according to the tillage practice and plant development stage
Degrune, Florine ULg; Dufrêne, Marc ULg; Taminiau, Bernard ULg et al

Poster (2015, April)

Agricultural practices have a strong impact on soil bacterial and fungal community composition. Furthermore, microbial community composition can change with the stage of plant development. We are ... [more ▼]

Agricultural practices have a strong impact on soil bacterial and fungal community composition. Furthermore, microbial community composition can change with the stage of plant development. We are interested in exploring these effects in relation to changes induced by agriculture (conventional and reduced tillage) and plant stage (germination and flowering) in soil conditions. Here, instead of examining this impact at a high taxonomic level such as phylum and/or class, thus missing potentially relevant information from lower levels, we propose an original method: exploiting the available sequence information at the lowest taxonomic level attainable for each operational taxonomic unit. Results show that some microbial communities were impacted only by the tillage practice , while others were impacted only by the stage of plant. Changes in microbial community composition could be due to the soil conditions induced by the soil practice and the stage of plant. [less ▲]

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See detailDimethylsulfoniopropionate (DMSP) cell quota of key Southern North Sea spring diatoms and Phaeocystis globosa
Speeckaert, Gaëlle ULg; Gypens, Nathalie; Lancelot, Christiane et al

Poster (2015, April)

Dimethylsulfide (DMS) in the ocean results of complex transformations of dimethylsulfoniopropionate (DMSP) produced by phytoplankton under different controls, including microbial transformation pathways ... [more ▼]

Dimethylsulfide (DMS) in the ocean results of complex transformations of dimethylsulfoniopropionate (DMSP) produced by phytoplankton under different controls, including microbial transformation pathways. The phytoplankton composition is an important factor of variability due to the species dependence of the DMSP production and conversion to DMS. To better appraise the link between phytoplankton diversity and the DMS(P) cycling in the Southern North Sea we present measurements of the DMSP cell quota of key spring phytoplankton species (Skeletonema costatum, Thalassiosira rotula, Rhizosolenia delicatula, Asterionella glacialis, Nitzschia closterium, Chaetoceros debilis, Chaetoceros socialis and Phaeocystis globosa) isolated from the North Sea and maintained in non-limiting and axenic laboratory culture conditions. Results are discussed with regards to literature data and hypothesis currently used in DMS(P) biogeochemical models. [less ▲]

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See detailFunctional MRI for predicting metastatic spreading at the time of surgery after neoadjuvant radiotherapy
LALLEMAND, François ULg; Leroi, Natacha ULg; Bahri, Mohamed Ali ULg et al

Poster (2015, April)

Neoadjuvant radiotherapy (NeoRT) improves tumor local control and tumor resection in many cancers. The timing between the end of the NeoRT and surgery is driven by the occurrence of side effects or the ... [more ▼]

Neoadjuvant radiotherapy (NeoRT) improves tumor local control and tumor resection in many cancers. The timing between the end of the NeoRT and surgery is driven by the occurrence of side effects or the tumor downsizing. Some studies demonstrated that the timing of surgery and the RT schedule could influence tumor dissemination and subsequently patient overall survival. Our aim is to evaluate with functional MRI the impact of the radiation treatment on the tumor microenvironment and subsequently to determine the best timing to perform surgery for avoiding tumor spreading. [less ▲]

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See detailRemote control of self-assembled magnetocapillary microswimmers
Grosjean, Galien ULg; Lagubeau, Guillaume ULg; Hubert, Maxime ULg et al

Poster (2015, April)

Physics governing the locomotion of microorganisms and other microsystems is dominated by viscous damping. An effective swimming strategy involves the non-reciprocal and periodic deformations of the ... [more ▼]

Physics governing the locomotion of microorganisms and other microsystems is dominated by viscous damping. An effective swimming strategy involves the non-reciprocal and periodic deformations of the considered body. Herein, we show that a magnetocapillary-driven self-assembly, composed of three soft-ferromagnetic beads, is able to swim along a liquid-air interface when driven by an external magnetic field. Moreover, the system can be fully controled, opening ways to explore low Reynolds number swimming and to create micromanipulators in various applications. [less ▲]

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See detailThe iPot Project: improved potato monitoring in Belgium using remote sensing and crop growth modelling
Piccard, I.; Nackaerts, K.; Gobin, A. et al

Poster (2015, April)

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See detailTillage as a tool to manage crop residue : impact on sugar beet production
Hiel, Marie-Pierre ULg; Degrune, Florine ULg; Parvin, Nargish ULg et al

Poster (2015, April)

Crop residues and plant cover represent a pool of organic matter that can be used either to restore organic matter in soils, and therefore maintain soil fertility, or that can be valorized outside of the ... [more ▼]

Crop residues and plant cover represent a pool of organic matter that can be used either to restore organic matter in soils, and therefore maintain soil fertility, or that can be valorized outside of the field (e.g. energy production). However, it is crucial that the exportation of residues is not done to the detriment of the system sustainability. Three long term experiments have been settled in the loamy region in Belgium. All of them are designed to study the effect of residues management by several tillage systems (conventional plowing versus reduced tillage) on the whole soil-water-plant system. SOLRESIDUS is a field experiment where we study the impact of crop residue management while in SOLCOUVERT and SOLCOUVERT-BIS, we study the impact of cover crop management. SOLRESIDUS was started in 2008. In this field, four contrasted crop residues managements are tested in order to contrast as much as possible the responses from the soil-water plant system. Two practices characterize the four modalities: soil tillage (ploughing at 25 cm depth or reduce tillage at 10 cm max) and residue management (exportation or restitution). SOLCOUVERT and SOLCOUVERT-BIS were started in 2012 and 2013 respectively. In those fields cover crop management is also diverse: destruction of the cover crop by winter ploughing, spring ploughing, strip tillage (with a chemical destruction if needed) or shallow tillage (with a decompaction before cover crop sowing). Although although the overall project aims at studying the impact of management on the whole soil-water-plant system, here we will only present the results concerning crop production (sugar beet) in SOLCOUVERT experiments. The presented data will include germination rate, crop development (biomass quantification and BBCH stages) weeds population, disease occurrence, pest occurrences, nitrogen uptake by plants, quality and quantity of harvested products.   [less ▲]

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See detailTesting the impact of stratigraphic uncertainty on spectral analysis of sedimentary time series
Martinez, Mathieu; Kotov, Sergey; De Vleeschouwer, David et al

Poster (2015, April)

Spectral analysis has become a key tool for identifying the imprint of astronomical forcing on sedimentary records. In a next step, the identified cycles often contribute to the construction of a precise ... [more ▼]

Spectral analysis has become a key tool for identifying the imprint of astronomical forcing on sedimentary records. In a next step, the identified cycles often contribute to the construction of a precise Geological Time Scale and to an in-depth understanding of past climate changes. Most of spectral analyses (Fast Fourier Transforms, the Multi-Taper Method. . . ) require a constant sample step. Unfortunately, an equally spaced geological data series is, in practice, nearly impossible to obtain from field sedimentary series. Usually, there is a 10% uncertainty on the field measurements of the stratigraphic thickness within sedimentary series. Hence, important uncertainties exist on the actual position of each sample. Another source of uncertainty are errors in a time-space model. In this study, we explore the impact that the stratigraphic uncertainty on the sample position has on the result of spectral analyses. To simulate this uncertainty, we developed a model based on the Monte Carlo randomisation of the distance between each successive point. In this way, the stratigraphic order of the data points is not affected after imp lementating this model. The application of this model to a theoretical sinusoid series and to several real sedimentary series shows that uncertainties in the actual position of samples can highly reduce the spectral powers of the frequencies ranging from the Nyquist Frequency up to 1/10 of the Nyquist Frequency. We the demonstrate that the precise reconstruction of the Milankovitch cycles in the sedimentary record requires a higher sampling density than previously suggested with, at least, 10 samples per thinnest cycle to be detected, i.e. 10 samples per precession cycle [less ▲]

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See detailInfusion of third-party mesenchymal stromal cells after liver transplantation: a phase 1, open-label, clinical study
DETRY, Olivier ULg; VANDERMEULEN, Morgan ULg; DELBOUILLE, Marie-Hélène ULg et al

Poster (2015, March 27)

Transplanted patients have to deal with numerous side effects of life-long dependence on immunosuppressive drugs. Paradoxically these drugs fail to prevent acute and/or chronic rejection in many cases ... [more ▼]

Transplanted patients have to deal with numerous side effects of life-long dependence on immunosuppressive drugs. Paradoxically these drugs fail to prevent acute and/or chronic rejection in many cases. Mesenchymal stromal cells (MSC) are multipotent and self-renewing bone marrow progenitors that have been shown both in vitro and in vivo as capable of (i) immunomodulation, (ii) anti-inflammation in case of ischemia/reperfusion injury, and (ii) stimulation of tissue repair. MSC could therefore be very interesting in organ recipients to limit chronic graft damage and to allow tolerance. This study aimed to be the first clinical evaluation of the safety and tolerability of MSC infusion after liver transplantation in a prospective, controlled, phase I study. Clinical grade MSCs were locally collected from the bone marrow of unrelated healthy donors. They were cultured in a GMP-compliant lab, underwent extensive quality controls and were frozen for storage in a MSC bank. When needed for patient treatment, MSC were thawed and intravenously injected into patients. 10 liver transplant recipients under standard immunosuppression (TAC-MMF-low dose steroids until day 30) received 1.5-3x106/kg MSC on post- operative day 3 ± 2. These patients were prospectively compared to a group of 10 control (MSC-) liver recipients. Primary endpoints were MSC infusion toxicity, and incidence of cancer and opportunistic infections at month 6. Secondary endpoints were patient and graft survivals and rejection at month 6, as well as the effects of MSC on recipients’ immune function and on immunohistology of at month 6 graft biopsies. No MSC infusional toxicity was observed. Both groups were comparable in terms of donor and recipient characteristics. There was no difference in primary end-points between control and MSC groups. No patient developed de novo cancer. There was no statistical difference in patient and graft survivals or in rejection rates. There was no graft rejection in the MSC group. Month-6 graft biopsies were not different according to Banff and fibrosis scores. This phase I study showed excellent tolerability and safety of a single infusion of third-party MSC after liver transplantation. There were no graft safety issues and no excess of immunosuppression after MSC injection. Further analyses of consequences of MSC injection on the immune profile are needed. The possibility of avoiding calcineurin-inhibitors with repeated MSC injections as main immunosuppressive therapy and/of tolerance induction by MSC infusion should be investigated by further studies. [less ▲]

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See detailApplications of stable isotopes in environmental studies at the University of Liege
Sturaro, Nicolas ULg; Borges, Alberto ULg; Das, Krishna ULg et al

Poster (2015, March 26)

Measurement and use of stable isotope ratios have a long history at the University of Liege (Belgium). Since at least 30 years, applications of stable isotopes in marine ecosystems have been developed ... [more ▼]

Measurement and use of stable isotope ratios have a long history at the University of Liege (Belgium). Since at least 30 years, applications of stable isotopes in marine ecosystems have been developed within the Laboratory of Oceanology and, more recently, within the Chemical Oceanography Unit. In the Laboratory of Oceanology, one research axis is the measurement of stable isotope composition (C, N, S) in organic matter to delineate trophic web structure and to study animal diet, their trophic niches and their alteration by human activities. This methodology has been successively applied worldwide in different habitats and ecosystems (marine, freshwater, terrestrial) in temperate and tropical areas. Mediterranean food web and fish trophic ecology have received a particular attention. Coupling between trophic ecology and ecotoxicology is another area of investigation. This has been applied mainly to marine vertebrates and freshwater ecosystems. Stable isotope labelling is also used in our laboratory to study and quantify various ecological processes such as inorganic nitrogen incorporation and trophic transfers. The laboratory facilities, renewed in 2012 and managed by Dr. Gilles Lepoint, are composed of an elemental analyser (EA, vario MICRO cube, Elementar) and a gas chromatography (GC, Agilent) coupled to an isotope ratio mass spectrometer (IRMS, Isoprime 100). The GC is also equipped with a quadrupole mass spectrometer. In 2014, the Chemical Oceanography Unit, headed by Dr. Alberto Borges, has acquired and implemented an off-axis cavity ring-down spectroscopy (CRDS) for the measurements of δ15Nα, δ15Nβ, δ18O of N2O. This enables characterization of the N2O origin in a variety of aquatic environments including groundwater in Wallonia, rivers and lakes in Wallonia and Africa, coastal environments (Scheldt estuary, Lake Grevelingen, North Sea), Mediterranean seagrass beds, and Antarctic and Arctic sea-ice. [less ▲]

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See detailUse of C, N and S stable isotope ratios to highlight resource segregation among hermit crabs from tropical seagrass meadows
Michel, Loïc ULg; Frederich, Bruno ULg; Lavitra, Thierry et al

Poster (2015, March 26)

Polyspecific seagrass meadows are ubiquitous features of tropical coastal zones. These ecosystems are of critical ecological importance, and provide a wide range of socio-economical services to local ... [more ▼]

Polyspecific seagrass meadows are ubiquitous features of tropical coastal zones. These ecosystems are of critical ecological importance, and provide a wide range of socio-economical services to local populations. Meadows however undergo multiple threats linked to human activities (increased nutrient input, overfishing, invertebrate overharvesting, etc.). It is currently hard to assess how seagrass meadows could respond to anthropogenic impacts due to poor knowledge of their functional ecology. In an effort to unravel trophic interactions ruling the food webs associated to seagrass beds of the Toliara Great Reef (SW Madagascar), we studied resource segregation between two common Diogenidae hermit crabs (Dardanus scutellatus and Ciliopagurus tricolor) using stable isotope ratios. C, N and S stable isotope ratios of bulk muscle tissue were measured via CF-EA-IRMS (Elementar Vario MicroCube EA coupled to an Isoprime 100 MS). Interspecific differences were noted in isotopic composition of carbon (δ13C = -12.22 ± 1.73 ‰ for D. scutellatus, δ13C = -14.55 ± 0.73 ‰ for C. tricolor), nitrogen (δ15N = 4.73 ± 0.53 ‰ for D. scutellatus, δ15N = 5.20 ± 0.61 ‰ for C. tricolor) and sulfur (δ34S = 14.08 ± 2.32 ‰ for D. scutellatus, δ34S = 16.73 ± 1.49 ‰ for C. tricolor), suggesting that the two species do not feed on the same items. In addition, SIBER (Stable Isotope Bayesian Ellipses in R) modeling based on C and N data clearly showed that no overlap was present in the core isotopic niches of the two species. It also indicated that the isotopic niche of D. scutellatus was greater than the one of C. tricolor, implying that the former feeds on a greater number of items than the latter. While hermit crabs are generally considered as omnivorous species, this study highlighted differences in the foraging ecology of D. scutellatus and C. tricolor. These differences could help to limit competition for food between these two species, and facilitate their coexistence in Malagasy seagrass beds. [less ▲]

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See detailEvaluation of pitch accuracy in solfeggio examinations: What about non-musical variables?
Larrouy, Pauline ULg

Poster (2015, March 24)

Background and aims In experimental settings, 81% of the variance of judges’ rating of pitch accuracy is explained by musical variables (precision of pitch intervals and respect of tonality) (Larrouy ... [more ▼]

Background and aims In experimental settings, 81% of the variance of judges’ rating of pitch accuracy is explained by musical variables (precision of pitch intervals and respect of tonality) (Larrouy-Maestri, Lévêque, Schön, Giovanni, & Morsonne, 2013). In ecological settings, non-musical variables influence judgments of music performances (i.e., McPherson & Thompson, 1998; Platz & Kopiez, 2012). This study aims to better understand the evaluation of pitch accuracy in the context of formative and summative solfeggio examinations at tertiary music level, for which live performances are evaluated. Method Twenty-one participants of conservatory were asked to learn simple melodies during solfeggio classes. They were evaluated two times (formative and summative examinations) by 3 judges. Each performance was also objectively analyzed regarding pitch accuracy (number of contour errors, precision of pitch intervals and respect of the tonal centre) with a computer-assisted method (Larrouy-Maestri & Morsomme, 2014). Results The 3 judges provided strongly and significantly correlated ratings. The musical criteria objectively analyzed explained 56% of the variance of the jury’s rating when the examination purpose was formative (p < .001) and 31% of the variance when the purpose was summative (p = .009). Interestingly, the predictive musical criteria differed depending on the examination’s purpose. In addition, the variance explained by our statistical model increased (from 56% to 67% and from 31% to 46%) when taking into account non-musical variables such as the gender of the music students. Conclusions Besides the educational perspectives, the proposed method appears interesting for examining the influence of non-musical variables on the pitch accuracy assessment in ecological contexts. [less ▲]

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See detailModelling of large-scale in situ ventilation test in clayey rock
Pardoen, Benoît ULg; Collin, Frédéric ULg; Talandier, Jean

Poster (2015, March 23)

see attached file

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See detailImproving knowledge on Forest elephant’s ecophysiology (Loxodonta africana cyclotis) for better wildlife conservation
Ngama, Steeve ULg; Vermeulen, Cédric ULg; Bindelle, Jérôme ULg

Poster (2015, March 21)

Conservation of large wildlife species is currently a major issue in Africa. Protected areas dedicated for biodiversity conservation unfortunately do not suffice and conservation practices must be ... [more ▼]

Conservation of large wildlife species is currently a major issue in Africa. Protected areas dedicated for biodiversity conservation unfortunately do not suffice and conservation practices must be extended to man-used areas. But in those areas conservation actions are limited because of conflicts between human and wildlife especially due to damages on crops. The worst crop raiders known are elephants because they can destroy the yearly harvest of a field in a single visit. This threatens not only people livelihoods but also elephants themselves when angry farmers retaliate by shooting or trapping them. After decades of investigations crop raiding drivers related to elephants’ ecophysiology remain largely unknown. A pilot study was conducted between July and November 2014 in Monts de Cristal National Park (Gabon, central Africa) to have a first view on environmental drivers to crop raiding. While the presence of some fruiting trees around crop fields lead to more damages, high slopes discouraged elephants. In further experiments, the link between the nutritive value of raided plants and the animal’s physiological requirements and status will be assessed through hormones and parasites measurements; while tracking of individual elephants’ movements using DNA analyses in feces will be done. [less ▲]

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See detailNiche modeling within and between species in the genus Erythrophleum : intergating phylogenetic data and environmental niche models to explore speciation mechanisms
Gorel, Anaïs ULg

Poster (2015, March 21)

In this study we investigated the climatic niche between and within closely related tropical tree species of the Erythrophleum genus (Fabaceae, Caesalpinioideae): E. ivorense, E. suaveolens and E ... [more ▼]

In this study we investigated the climatic niche between and within closely related tropical tree species of the Erythrophleum genus (Fabaceae, Caesalpinioideae): E. ivorense, E. suaveolens and E. africanum. Two major hypotheses, the refuge theory and the ecological gradient hypothesis, have been developed to explain the current distribution of tree clades across tropical Africa. To identify the speciation mechanisms, we used a combination of geographic data and environmental factors to quantify the degree of niche conservatism (or divergence). We used two sets of distribution data for the purpose of this study. Species distribution data for the whole of tropical Africa was gathered from herbarium records. Distribution data of the two sister species E. ivorense and E. suaveolens assigned to genetic cluster were available for the lowland tropical forests of western and central Africa. Using a Species Distribution Model approach based on MaxEnt algorithm we tested for the environmental differences between species and genetic clusters within species. At species level, the climatic niche significantly differed and only slightly overlapped, suggesting a parapatric speciation along a climatic gradient. Within the two sister species, the niche of the parapatric central African genetic clusters suggests mostly a secondary contact following the recolonization from different forest refugia. [less ▲]

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See detailInternational Classification of Primary Care in a cross-lingual terminology portal
Jamoulle, Marc ULg; Pizzanelli, Miguel; Grosjean, Julien et al

Poster (2015, March 20)

International Classification of Primary Care in a cross-lingual terminology portal M. Jamoulle1, M. Pizzanelli2, J. Grosjean 3 , G. Kerdelhué 3, SJ. Darmoni 3&4 1 Department of General practice, Liege ... [more ▼]

International Classification of Primary Care in a cross-lingual terminology portal M. Jamoulle1, M. Pizzanelli2, J. Grosjean 3 , G. Kerdelhué 3, SJ. Darmoni 3&4 1 Department of General practice, Liege University, Belgium 2 Unidad docente asistencial rural de Florida, Uruguay 3 Deparment of Biomedical Informatics, Rouen University Hospital, Normandy & TIBS, LITIS EA 4108, France 4 LIMICS, INSERM, U1142, Paris, France. ICPC is available in the HeTOP cross-lingual terminology portal (URL: www.hetop.eu) [1] in 19 languages, mostly European (e.g. Spanish, Portuguese) but also in Japanese or Mandarin. The HeTOP interface has been also translated in 10 languages, including by Wonca colleagues (in Turkish, Vietnamese and Romanian). This is very important for non-English speakers to access a health Web site in his/her native language. Thanks to a partial manual mapping between ICPC2 and MeSH, it is now also possible to query PubMed from 20% of ICPC2 codes. This task is time consuming as in lot of cases, the mapping is 1 to N (one ICPC code generates several MeSH terms; e.g. the ICPC term "diverticular disease" is mapped to two MeSH terms " diverticulosis, colonic" and " diverticulitis". HeTOP currently contains 56 health terminologies and ontologies (only 17 are included in UMLS as most of them are French terminologies), 1,951,834 concepts, 6,636,000 terms, 8,023,181 relations and 1,340,855 relations. Overall, HeTOP contains 108 millions of SPARQL triplets. These figures underlines the possible application of the so called "health big data". Overall, the number of distinct UMLS concepts with at least one French translation in UMLS (MeSH, MedDRA, WHOART, ICPC) is 45,405 vs. 317,539 in HeTOP. 1. Grosjean, J; Merabti, T; Griffon, N; Dahamna, B & Darmoni, SJ. Teaching medicine with a terminology/ontology portal. Stud Health Technol Inform 2012:180;949-53. [less ▲]

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See detailElectronic nose Technology for reactor state and biogas quality assessment in anaerobic digestion
Adam, Gilles ULg; Lemaigre, Sébastien; Goux, Xavier et al

Poster (2015, March 17)

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See detailEtude morphologique de l'effet de l'irradiation gamma sur les amidons de blé, de maïs et de pomme de terre
Atrous, Hager; Ben Bettaïeb, Nasreddine; Danthine, Sabine ULg et al

Poster (2015, March 15)

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See detailPhysicochemical properties and thermal behaviour of African wild mango (Irvingia gabonensis) seed oil.
Yamoneka, Juste; Malumba Kamba, Paul ULg; Blecker, Christophe ULg et al

Poster (2015, March 15)

Plants belonging Dacryodes and lrvingia genus have great economic importance in Central and West Africa. lrvingia gabonensis (IG) produces a seed rich in fats, traditionally used as a soup thickener ... [more ▼]

Plants belonging Dacryodes and lrvingia genus have great economic importance in Central and West Africa. lrvingia gabonensis (IG) produces a seed rich in fats, traditionally used as a soup thickener. Fruit of Dacryodes edulis (DS) contains a pulp how are also rich in fat. Its seed constitute a big waste problem in towns and village remains not exploitable by local people however that may be valued as a resource for various components. Some study shows that this seed contented a proportion of oils that would be an alternative in the substitution of diesel relevant to their physicochemical properties. Despite the potential of two different oils, theirs scientific data still lack. In this work, thermo-physical behaviour of those two oils is compared in the aim to improving knowledge about properties of those oils that will promote their valorisation in industry scale. The result of this investigation showed that IGO have a highest proportion of oil content with 72.38% compared to DSO (14.64%). IGO is rich in myristic (49.8%) and lauric fatty acid (37%) but DSO sample was found to possess a higher proportion of linoleic acid (35.13%), palmitic (32.67%), oleic (17.70%) but lower proportion of stearic (9.97%). SFC of IGO was the highest at all temperatures. IGO is solid at room temperature with a complete melting at 40°C but DSO is liquid at room temperature. The polymorphism profile of IGO and DSO shows the 13' form stable during heating and a transition to liquid state without passage at β form. [less ▲]

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See detailDéveloppement d'un modèle mathématique d'identification des différents tissus externes de son de blé dur et tendre (Triticum durum et Triticum aestivum) basé sur l'étude histologique macroscopique et microscopique et la composition biochimique des fractions
Ben Amouda, Mohamed Salah; Roiseux, Olivier; Olive, Gilles et al

Poster (2015, March 15)

Le blé est constitué de trois régions : l’albumen, les enveloppes et le germe. Le blé sert depuis longtemps de nourriture de base à l’homme pour donner, après mouture, à la farine dans le cas des blés ... [more ▼]

Le blé est constitué de trois régions : l’albumen, les enveloppes et le germe. Le blé sert depuis longtemps de nourriture de base à l’homme pour donner, après mouture, à la farine dans le cas des blés tendres, ou à la semoule dans le cas des blés durs. Le produit obtenu correspond à la majorité de l’albumen. Le son de blé est quant à lui un coproduit de cette transformation. C’est un empilement de différents tissus : péricarpe externe et interne, testa, épiderme et aleurone. Actuellement, la valorisation du son de blé reste faible malgré son potentiel nutritionnel. Or ce potentiel permettrait un développement d’additifs alimentaires à haute valeur ajoutée si un fractionnement correct suivi d’une analyse histochimique complète des factions obtenues pouvait être réalisés. Parmi les méthodes de fractionnement, note choix s’est porté sur le debranning qui se base sur le retrait séquentiel des différentes couches extérieures du blé (voir la communication « Mise au point du fractionnement par debranning des tissus périphériques du blé tendre (Triticum aestivum) et du blé dur (Triticum durum) ». Afin de quantifier l’efficacité du fractionnement, l’investigation de la répartition des tissus au sein des fractions produites a été réalisée par l’étude macroscopique (visuelle) et microscopique (coloration histologique spécifique) des grains et des fractions. Un modèle mathématique qui permet l’appréciation de la distribution des couches dans les différentes fractions a également été développé sur base des bio-marqueurs et de la composition biochimique des fractions. L’étude visuelle macroscopique montre que les grains dans tous les cas attaqués de façon hétérogène et ce en raison de la géométrie particulière des grains de blé. L’étude histologique microscopique montre que, malgré cela, certaines fractions sont enrichies en tissus particuliers. Donc, quelque soit la variété étudiée, les fractions obtenues par debranning présenteront toujours une hétérogénéité de composition tissulaire. Après étude du profil nutritionnel (analyse composition chimique), la variété Karim semble la plus intéressante, car elle est riche en protéines, lipides et minéraux. Au niveau des fractions, pour toutes les variétés, la fraction F1 présente le meilleur potentiel. [less ▲]

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See detailTECHNICAL CHALLENGES IN CHOLESTEROL REMOVAL FROM DAIRY PRODUCTS
Malik, Priyanka ULg; Danthine, Sabine ULg; Paul, Aman ULg et al

Poster (2015, March 15)

Milk is a natural complex system present as oil in water emulsion. The natural organisation of milk fat globules is stabilized by the presence of a natural membrane, called the milk fat globule membrane ... [more ▼]

Milk is a natural complex system present as oil in water emulsion. The natural organisation of milk fat globules is stabilized by the presence of a natural membrane, called the milk fat globule membrane. It has tripartite structure consisting of a monolayer facing the inner triacylglycerol core and an external bilayer. Apart from giving the nutritive value, milk fat globule membrane also contributes towards the techno-functional properties of the dairy products. The milk fat globule membrane is composed of both polar lipids and proteins. Cholesterol is also present in milk fat globule membrane and accounts for about 2% of milk fat globule membrane. Increased consumer awareness has created a perceived demand for low cholesterol products. The World Health Organization and American Heart Association has also recommended that consumers reduce their consumption of saturated fatty acids and cholesterol to lower the risk of coronary heart disease. Therefore, many researchers have developed different methods for reducing cholesterol in dairy and food products. These methods include physical process (vacuum steam distillation, short path molecular distillation and supercritical fluid extraction), biological process (cholesterol reductase and cholesterol oxidase), complexation method (adsorption with saponin, digitonin and cyclodextrin) and chemical process. Most of these methods are very efficient in process of cholesterol removal. However, most of these methods have various drawbacks for application in dairy industry like, formation of toxic oxidation products, denaturation of proteins, loss of low molecular weight triglycerides, loss of volatile components, loss of flavour compounds etc. This leads to loss of nutritive value of dairy products. Thus, the objectives of cholesterol removal from milk and milk products should be, firstly focusing on the maximum cholesterol removal, secondly maintaining the nutritional quality comparable to the control and thirdly the process of cholesterol removal should not compromise the techno functional properties of the dairy products. [less ▲]

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See detailCaractérisation physico-chimique et structurale de la poudre et des ulvanes de l'algue ulva lactuca
Guidara, Mariem; Yaich, Hela; Garna, Haikel et al

Poster (2015, March 15)

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See detailThermal and structural behavior of two lauric fats compared to AMF in bulk and oil-in-water emulsion states
Petrut, Raul Flaviu ULg; Anihouvi, Prudent Placide; Blecker, Christophe ULg et al

Poster (2015, March 15)

In a previous study the thermal and polymorphic behavior of four different industrial lauric fats which are sold under the same commercial description, was compared (1). According to the findings the four ... [more ▼]

In a previous study the thermal and polymorphic behavior of four different industrial lauric fats which are sold under the same commercial description, was compared (1). According to the findings the four fats were split in two groups based on the similarities found at polymorphic level. In the present paper two of these industrial lauric fats (F1 and F2, one from each group) were incorporated into oil -in -water emulsions. The objective of this study was to point out the differences in the crystallization and polymorphic behavior between bulk and emulsified fat. Moreover anhydrous milk fat (AMF) was used in the same way for comparison. For that purpose, the fats were investigated for their thermal and polymorphic behavior by differential scanning calorimetry (DSC) and X-ray diffraction (XRD), both in bulk and emulsified state. The DSC and X -Ray investigations made possible the observation of the differences in the crystallization behavior and kinetics that occurred for those fats in the bulk and emulsified state. 1. Anihouvi, P.P., C. Blecker, A. Dombree, S. Danthine, Comparative Study of Thermal and Structural Behavior of Four Industrial Lauric Fats, Food Bioprocess Technol. 6:3381-3391 (2013) [less ▲]

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See detailAnhydrous Milk Fat enrichment with 13C-­triacylglycerol tracers: effects on thermal and structural behavior.
Danthine, Sabine ULg; Vors, Cécile; Blecker, Christophe ULg et al

Poster (2015, March 15)

Dietary lipids are incorporated in food products under different types of structures, e.g., as dispersed lipid droplets (in oil -in -water emulsions, like creams) or as a continuous lipid phase (in water ... [more ▼]

Dietary lipids are incorporated in food products under different types of structures, e.g., as dispersed lipid droplets (in oil -in -water emulsions, like creams) or as a continuous lipid phase (in water -in -oil emulsions, like butter for example). The crystallization, melting behavior and polymorphic stability of fats are determined by the behavior of the TAGs they contain. In clinical studies, there is a need to add some 13C TAGs as tracers to the ingested fats in order to track their metabolic fate. However, this procedure could modify the physicochemical properties of the fat. The present study was conducted in the framework of a clinical trial aiming at highlighting the effect of the physical structure of a fat (droplets in 0/W emulsion or bulk) in a meal on the absorption, chylomicron transport and further metabolic handling of dietary fatty acids (1). We therefore monitored the thermal and polymorphic behavior of anhydrous milk fat (AMF) enriched in tracers (a mixture of tripalmitin, triolein and tricaprylin; at 2 different concentrations: 1.5 and 5.7 wt%) using DSC and XRD and further compared it to the native AMF. The addition of 13C TAGs modified the AMF melting profile, especially at high concentration. The enriched AMF was completely melted at around 37°C, i.e. close to the body temperature. However, under some conditions, the AMF enriched in high 13C TAGs concentration remained crystallized at 37°C. Similar trends were observed in both systems (bulk vs emulsified). Moreover, AMF polymorphic behavior was also modified upon tracer addition. While only β’ form was observed in the native AMF, the 13 -form was detected in the AMF containing high 13C TAGs concentration. Importantly, low concentration of tracers should not have high impact on human digestive physiology. However more attention should be paid to physicochemical structure when high concentrations are added. (1) Vors et al. 2013. Modulating absorption and postprandial handling of dietary fatty acids by structuring fat in the meal: a randomized cross -over clinical trial. Am J Clin Nutr, 97(1): 23-36. [less ▲]

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See detailPhysicochemical properties and thermal behaviour of African wild mango (Irvingia gabonensis) seed oil.
Yamoneka, Juste; Malumba Kamba, Paul ULg; Blecker, Christophe ULg et al

Poster (2015, March 15)

African wild mango (lrvingia gabonensis) is now recognized for its numerous food and medicinal uses. This plant produces seeds rich in fat, which is traditionally used as a soup thickener. in the present ... [more ▼]

African wild mango (lrvingia gabonensis) is now recognized for its numerous food and medicinal uses. This plant produces seeds rich in fat, which is traditionally used as a soup thickener. in the present study, the proximate composition of seeds from lrvingia gabonensis is reported. The oil from the seeds was then solvent extracted; its fatty acid (FA) and triacylglycerol (TG) profiles were determined. Besides this chemical characterization, the melting and crystallization behaviour of the extracted fat was studied by pNMR, DSC and X-ray diffraction. The result of this investigation showed that the seeds from lrvingia gabonensis (IG) represent an important source of lipids (69-75%), rich in myristic (49.8%) and lauric acid (37%). This fat can be classified among "lauric fats". IG oil presents a good oxidative stability due to its low content in unsaturated fatty acid. The melting profiles of IG oil indicates that a high amount of fat remains solid at temperatures up to 30°C; the complete melting was detected at around 40C. The most stable polymorph of this fat is the β'1 -form. [less ▲]

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See detailMise au point du fractionnement par debranning des tissus périphériques du blé tendre (Triticum aestivum) et du blé dur (Triticum Durum)
Roiseux, Olivier; Ben Hamouda, Mohamed Salah; Olive, Gilles et al

Poster (2015, March 15)

Le blé est constitué de trois régions : l’albumen, les enveloppes et le germe. Depuis longtemps, le blé est broyé pour donner soit la farine dans le cas des blés tendres, soit de la semoule dans le cas ... [more ▼]

Le blé est constitué de trois régions : l’albumen, les enveloppes et le germe. Depuis longtemps, le blé est broyé pour donner soit la farine dans le cas des blés tendres, soit de la semoule dans le cas des blés durs, ceci correspond en fait à la majorité de l’albumen. Le son de blé est un coproduit de cette transformation et consiste en un empilement de différents tissus : péricarpe externe et interne, testa, épiderme et aleurone. A l’heure actuelle, la valorisation du son de blé est limitée malgré son potentiel nutritionnel. Un fractionnement spécifique de ces tissus, conduisant à la production de fractions ciblées à haute valeur ajoutée, permettrait de mieux exploiter ce potentiel. Parmi les méthodes de fractionnement par voie sèche, le debranning permet le retrait séquentiel des différentes couches extérieures du blé mettant en jeu l’abrasion contre une surface abrasive et la friction des grains entre eux. L’étude a porté sur deux variétés de blé tendre (Julius et Sahara) et deux de blé dur (Karim et Razzek). En raison de différences physiques comme la dureté ou la taille et la forme des grains, des cycles de traitement adéquats pour chacun des variétés dans le but de mettre en évidence leurs différences comportementales. Les quatre fractions (F1 ; F2 ; F3 ; F4) obtenues ont alors été analysées statistiquement (moyenne, coefficient de variation, minimum et maximum, intervalles de confiance) afin de juger de la conformité de ces fractions en termes de pourcentage massique par rapport au but désiré. Les moyennes et intervalles de confiance montrent que les fractions développées sont conformes aux couches histologiques d’un point de vue massique, vis à vis des valeurs « objectifs » fixées par rapport à la littérature scientifique. [less ▲]

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See detailFood Compounds from Meadow Grasshoppers
Paul, Aman ULg; Frederich, Michel ULg; Uyttenbroeck, Roel ULg et al

Poster (2015, March 15)

Eating insects as food, particularly grasshopper is practiced in many cultures throughout the world. Meadow grasshopper (Chorthippus parallelus) is commonly found in Europe and some part of Asia. It is ... [more ▼]

Eating insects as food, particularly grasshopper is practiced in many cultures throughout the world. Meadow grasshopper (Chorthippus parallelus) is commonly found in Europe and some part of Asia. It is already known that grasshoppers of Chorthippus species are consumed as food in countries such as Thailand. With the aim of evaluating the nutritional potential of this insect species the proximate nutritional composition of grasshoppers caught from the local fields was realized. Besides this, the fatty acid profile of extracted lipids, amino acid profile and mineral composition of the insect was also revealed. Results suggest that meadow grasshopper is an excellent source of protein and essential amino acids. Lipids extracted from the grasshopper have an interesting fatty acid composition. Also the grasshopper contains some minerals that are important for body. With such protein content, amino acid profile, fatty acid profile of the lipids and mineral content this grasshopper species could present an interesting alternate to conventional protein sources. [less ▲]

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See detailThe living of the green microalga Chlamydomonas reinhardtii in day/night cycles
Willamme, Rémi ULg; Alsafra, Zouheir; Alsafra, Rameshkumar et al

Poster (2015, March 13)

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See detailConcomitant nodal involvement by Langerhans Cell Histiocytosis and Hodgkin Lymphoma
Geurten, Claire ULg; THIRY, Albert ULg; Jamblin, Paul et al

Poster (2015, March 12)

Introduction : Langerhans cell histiocytosis is defined as a clonal neoplastic proliferation of myeloid dendritic cells that upon activation migrate from the mucosal to lymph nodes. Definitive diagnosis ... [more ▼]

Introduction : Langerhans cell histiocytosis is defined as a clonal neoplastic proliferation of myeloid dendritic cells that upon activation migrate from the mucosal to lymph nodes. Definitive diagnosis is made by anatomo-pathological and immunohistochemical analysis. Langerhans cell histiocytosis is rarely, yet not exceptionally, found coexisting with other malignant neoplasms, suggesting it might arise in reaction to the cytokinic secretion of malignant cells. Case : We report the case of a 10-year-old female presenting with an isolated laterocervical lymphadenopathy and a mild general condition alteration tracing back to two months earlier. Nodal biopsy was performed and revealed concomitant involvement by Langerhans cell histiocytosis and Hodgkin lymphoma. Treatment of lymphoma led to the disappearance of the whole symptomatology. Discussion : Literature beholds reports of 30 cases of the simultaneous occurence of Hodgkin lymphoma with Langerhans cell histiocytosis, which is more than fortuitous regarding the low incidence of both diseases. A common etiology could explain such an association, but it might also be possible that background inflammatory cells of Hodgkin lymphoma stimulate the proliferation of Langerhans cells, making it a reactive process when occurring simultaneously with other neoplasms. Clinicians should thus be aware of the possibility of this association and carefully exclude any other life-threatening malignant proliferation when confronted to apparently isolated Langerhans cell histiocytosis. [less ▲]

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See detailGenetic Control of Flowering Time in Arabidopsis: an Interactive Database
Bouché, Frédéric ULg; Lobet, Guillaume ULg; Tocquin, Pierre ULg et al

Poster (2015, March 12)

The transition to flowering is an essential step of the plant life cycle that is tightly controlled by both endogenous and environmental cues. Its regulation is extremely complex and involves hundreds of ... [more ▼]

The transition to flowering is an essential step of the plant life cycle that is tightly controlled by both endogenous and environmental cues. Its regulation is extremely complex and involves hundreds of genes that are part of highly interconnected pathways. Our knowledge of the molecular mechanisms governing the floral induction of Arabidopsis thaliana increases quickly and a significant number of reviews are published every year on this topic. However, most of them focus on a single pathway without highlighting the interconnections existing between them. Furthermore, those reviews become rapidly outdated, since our comprehension of the genetic control of flowering time evolves continuously. Hence, we believe that the current landscape of flowering time research in Arabidopsis misses an exhaustive repository of the genes involved in the control of flowering and their regulatory pathways. Here, we present a new interactive resource built around a curated database of the flowering time genes that brings together multiple pieces of information such as their function, the flowering time phenotype of mutants and overexpressing lines, the related key publications, etc. Our website thus gives access to a curated and exhaustive list of the genes involved in the regulation of flowering time in Arabidopsis as well as the regulatory pathways controlling their expression. Because of its flexibility, the database is highly dynamic and will be periodically updated with the future breakthroughs in this domain. [less ▲]

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See detail“Rhizoponics”: a novel hydroponic rhizotron for root system analyses on mature Arabidopsis thaliana plants
Mathieu, Laura ULg; Lobet, Guillaume ULg; Tocquin, Pierre ULg et al

Poster (2015, March 10)

Well-developed and functional roots are critical to support plant life and reach high crop yields. Their study however, is hampered by their underground growth and characterizing complex root system ... [more ▼]

Well-developed and functional roots are critical to support plant life and reach high crop yields. Their study however, is hampered by their underground growth and characterizing complex root system architecture therefore remains a challenge. In the model plant Arabidopsis thaliana, in vitro culture remains the easiest and preferred method to study root development, which limits the analyses to young seedlings. We present here an innovative design of hydroponic rhizotron (rhizoponics) designed for the root system analysis of adult plants of Arabidopsis thaliana. [less ▲]

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See detailA new case of microdeletion 14q32.3
Uwineza, Annette ULg; BULK, Saskia ULg; CABERG, Jean-Hubert ULg et al

Poster (2015, March 06)

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See detailA tale of two anomalies. A paternal duplication and a maternal deletion of 15q13
BULK, Saskia ULg; Decortis, Thierry ULg; Rondia, G et al

Poster (2015, March 06)

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See detailQuaternary prevention, a GP/FM construct, based on patient-doctor relationships
Jamoulle, Marc ULg; Roland, Michel; Tsoi, Gene

Poster (2015, March 04)

Story of the building of the concept of Quaternary prevention

Detailed reference viewed: 26 (3 ULg)
See detailBlue sky and green bugs – How physical parameters and algal speciation influence DMSP and DMS profiles in Antarctic winter sea ice
Uhlig, C.; Rintala, J.-M.; Tison, J.-L. et al

Poster (2015, March)

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See detailEtude GEROX : Evaluation du statut de stress oxydant
CHRISTELBACH, SOPHIE; RICOUR, Céline ULg; Dardenne, Nadia ULg et al

Poster (2015, March)

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See detailStrain localization modelling around an underground gallery in Mol with an analysis of the contact pressure on the lining
Salehnia, Fatemeh ULg; Dizier, Arnaud; Li, Xiang Ling et al

Poster (2015, March)

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See detailTowards a yeast reference interactome
Desbuleux, Alice ULg

Poster (2015, March)

Despite an increasing number of interactomic datasets already available for model organisms and humans, many aspects remain contradictory, debatable or unclear due to the lack of complete high-quality ... [more ▼]

Despite an increasing number of interactomic datasets already available for model organisms and humans, many aspects remain contradictory, debatable or unclear due to the lack of complete high-quality networks. It has, for instance, been proposed that macromolecule connectivity in interactome maps reflects functional importance, functional relatedness, pleiotropy, implication in diseases, and other important biological characteristics. The most notorious example of such relationships concerns so-called essential genes believed to correspond to highly connected hubs that are critical to network integrity. Such claims have led to debate in the literature because connectivity could also be explained by bias and uneven coverage of the interactome space. To provide fresh insight into these questions, we produced a new, systematic interactome map for S. cerevisiae, organism for which a plethora of systematic interactomic and functional data is available. This alternative view of the interactome network was generated by modifying our screening pipeline based on our empirically-controlled framework. Using a new high-quality ORFeome collection and a new assay version, we systematically performed three replicate yeast-two hybrid screens. This produced a map of 1,200 protein-protein interactions, which, while of similar size as previously published interactome maps, covers the entire proteome without bias. These interactions were subsequently successfully validated using an orthogonal protein complementation assay based on a split Gaussia princeps luciferase. The latest analyses of this new map and progress towards generating a first Yeast Reference Interactome map will be presented. [less ▲]

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See detailAutoimmune thyroid diseases in early childhood three case reports
GUFFINS, A; HARVENGT, Julie ULg; LUYCKX, F et al

Poster (2015, March)

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See detailHow snow affects air-sea ice CO2 fluxes ?
Delille, Bruno ULg; Kotovitch, Marie ULg; Van Der Linden, Fanny ULg et al

Poster (2015, March)

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See detailELICITOR SCREENING TO PROTECT WINTER WHEAT AGAINST ZYMOSEPTORIA TRITICI BLOTCH
Le Mire, Géraldine ULg; Siah, Ali; Jijakli, Haissam ULg

Poster (2015, March)

Plant protection strategies are strongly focused today on the development of alternative methods in order to complete or replace conventional chemical inputs. Elicitors of biological origin are ... [more ▼]

Plant protection strategies are strongly focused today on the development of alternative methods in order to complete or replace conventional chemical inputs. Elicitors of biological origin are increasingly considered as a promising tool as biocontrol agents. They offer the possibility, through the induction of plant natural defences, to preventively protect plants against a large spectra of diseases. Multiple elicitors have already been identified since their first discovery in the late 70s, but few research has been focused on crop pathogens although such diseases can strongly impact both yield and grain quality. We describe hereby a method of elicitor screening to protect wheat against Zymoseptoria tritici. Focus is made on the importance of a good disease infection protocol in order to achieve screening tests. [less ▲]

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See detailCortical responses to transcranial magnetic stimulation during Non-Rapid Eye Movement Sleep
Gosseries, Olivia ULg; Jaakko, Nieminen; Siclari, Francesca et al

Poster (2015, March)

Transcranial magnetic stimulation coupled to high-density electroencephalography (TMS-EEG) allows for directly and non-invasively stimulating the brain and recording the subsequent cortical response ... [more ▼]

Transcranial magnetic stimulation coupled to high-density electroencephalography (TMS-EEG) allows for directly and non-invasively stimulating the brain and recording the subsequent cortical response. Previous TMS-EEG studies have shown clear-cut differences between conscious and unconscious conditions. When subjects are unconscious, as in non-rapid eye movement (NREM) sleep early in the night (stage N3), anesthesia or coma, TMS typically triggers a stereotypical and local slow-wave response. When they are conscious, as in normal wakefulness and rapid eye movement sleep (REM) sleep, brain responses to TMS are long-lasting, widespread, complex, and differentiated. In this study, we performed TMS-EEG during NREM sleep in stage 2 (N2) and N3 on 7 healthy participants. Brain activity was recorded using a 60-channel TMS-compatible EEG and single-pulse TMS was applied (up to 285 pulses per session) on the superior parietal cortex. After each TMS session (5 to 15 sessions per night), subjects were awakened to ask for a dream report. TMS-EEG responses were analyzed using the global mean field amplitude (GMFA), the perturbational complexity index (PCI), as well as time-frequency measures. Our results show that the TMS-EEG response during N3 is larger and slower than during N2 sleep. The GMFA is higher and PCI is lower in N3 as compared to N2 sleep. Moreover, N3 recordings showed activation at lower frequency bands after TMS as compared to N2 sleep. Additionally, TMS-EEG responses vary depending on whether subjects do or do not report a dream. TMS-EEG might provide valuable information for characterizing neurophysiological fluctuations and levels of consciousness within NREM sleep. [less ▲]

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See detailAlignments of quasar axes with large-scale structures
Hutsemekers, Damien ULg; Braibant, Lorraine ULg; Pelgrims, Vincent ULg et al

Poster (2015, March)

Based on measurements of optical linear polarization of quasars belonging to large groups at redshift z ~ 1.3, we found that quasar spin axes are likely parallel to their host large-scale structures ... [more ▼]

Based on measurements of optical linear polarization of quasars belonging to large groups at redshift z ~ 1.3, we found that quasar spin axes are likely parallel to their host large-scale structures (Hutsemékers et al. 2014). These observations can constrain models of the coevolution of AGN, galaxies and large-scale structures. [less ▲]

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See detailA two-surface viscoplastic model for saturated clays
Hong, P.Y.; Cui, Y.J.; Pereira, J.M. et al

Poster (2015, March)

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Peer Reviewed
See detailCharacterization of Venom Peptides using Microfluidic Separation Techniques coupled to Mass Spectrometry (LC-MS and CE-MS)
Degueldre, Michel ULg; Delvaux, Cédric ULg; Far, Johann ULg et al

Poster (2015, March)

More than the half of the principal sub-kingdoms of the animal world contains species that produce venom whose purposes are to immobilize, kill and pre-digest the preys. These venoms represent an ... [more ▼]

More than the half of the principal sub-kingdoms of the animal world contains species that produce venom whose purposes are to immobilize, kill and pre-digest the preys. These venoms represent an exceptionally rich source of various biologically active peptides, both in their structures and their effects, which are more and more useful for human being1. Yet, the total characterization of such complex samples require advanced analytical techniques mainly due to the complexity of the sample (hundreds of compounds), the limited quantities usually available and the presence of numerous PTMs, especially disulfide bridges and specific folding. Here we present a method that combines LC and CE separation techniques coupled to mass spectrometry (MS) to characterize the peptide composition of the snake venom Naja atra. The characterization will not only focus on the toxin sequencing (LC-MS and LC-MS/MS), but will also aim at analyzing the folding of the toxins (CE-MS). To this end, native and reduced/alkylated toxins will be analyzed by both techniques. Final result targets the determination of the global hydrophobic pattern and native tridimensional folding of these strongly reticulated peptides. (1) Richard J. Lewis & Maria L. Garcia, Therapeutic potential of venom peptides. Nature Reviews Drug Discovery 2003, 2, 790-802. [less ▲]

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See detailCan the exploration of left space be induced implicitly in unilateral neglect?
Wansard, Murielle ULg; Bartolomeo, Paolo; Vanderaspoilden, Valérie et al

Poster (2015, March)

The purpose of the present study was to explore the ability of neglect patients to detect and exploit the predictive value of a cue to respond more quickly and accurately to targets on their ... [more ▼]

The purpose of the present study was to explore the ability of neglect patients to detect and exploit the predictive value of a cue to respond more quickly and accurately to targets on their contralesional side in a Posner spatial cueing task. The majority of the cues (i.e. 80%) were invalid, indicating that the target would appear on the opposite side, although patients were not informed of this bias. Our results demonstrate that some neglect patients were able to extract the cue’s predictability and use it to orient faster toward the left. This cueing effect was present even in patients who were subsequently unable to describe the predictive character of the cues, and thus was not modulated by reportable awareness of the cue-target relation. [less ▲]

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See detailImaging air filled porosity in sea ice cover: Implication for sea ice permeability and gas exchange at the ice-atmosphere interface
Crabeck, O,; Galley, R,; Else, B, et al

Poster (2015, March)

Detailed reference viewed: 18 (0 ULg)
See detailIsolation of cultivable viruses from Antarctic wintertime sea ice
Luhtanen, A.-M.; Bamford, D.; De Jong, J. et al

Poster (2015, March)

Detailed reference viewed: 14 (0 ULg)