Last 7 days
Bookmark and Share    
See detailGenomics and ecological adaptation: metal hyperaccumulation in Arabidopsis halleri
Hanikenne, Marc ULg

Conference (2016, September 27)

Detailed reference viewed: 27 (5 ULg)
Peer Reviewed
See detailDEVELOPMENT OF NOVEL CATIONIC AND LIGAND-GRAFTED ANIONIC LIPOSOMES FOR BRAIN-TARGETED DRUG DELIVERY
Karim, Reatul ULg; Palazzo, Claudio ULg; Laloy, Julie et al

Poster (2016, September 27)

Detailed reference viewed: 26 (4 ULg)
Full Text
Peer Reviewed
See detailInfluence of groundwater exchanges on the efficiency of Underground Pumped Storage Hydroelectricity plants using open pit mines
Pujades, Estanislao ULg; Bodeux, Sarah ULg; Orban, Philippe ULg et al

Poster (2016, September 27)

Underground Pumped Storage Hydropower (UPSH) plants can be used to manage the production of electrical energy according to the demand. These plants consist in two reservoirs, the upper one is located at ... [more ▼]

Underground Pumped Storage Hydropower (UPSH) plants can be used to manage the production of electrical energy according to the demand. These plants consist in two reservoirs, the upper one is located at the surface while the lower one is underground. The energy is stored by pumping water from the lower to the upper reservoir and produced by releasing water from the upper to the lower one. As a result, the hydraulic head in the lower reservoir varies continuously. UPSH plants interact with the surrounding aquifers exchanging groundwater. These groundwater exchanges, which play an important role in the evolution of the hydraulic head inside the underground reservoir, are a fact of concern in the selection of pumps and turbines because their efficiency varies with respect to the head difference between the two reservoirs. Therefore, the aquifer parameters should be considered in the selection of pumps and turbines. In this context, with an UPSH plant made up by an open pit mine, we study numerically (1) the influence of groundwater exchanges on the efficiency and (2) how the hydraulic head evolution varies depending on the aquifer properties. The relation among the groundwater exchanges, the efficiency of pumps and turbines and the aquifer parameters is considered by comparing the numerical results of several simulations. It is shown that groundwater exchanges are not negligible when optimizing the efficiency of UPSH plants. A priori, low hydraulic conductivity geological media were preferred to decrease interactions with the open-pit or the cavity used as lower reservoir. Taking into account the pump/turbine performance curves, it appears that, on the contrary, the global efficiency would be increased if the surrounding medium facilitates large groundwater exchanges because hydraulic head variations are softened. [less ▲]

Detailed reference viewed: 18 (6 ULg)
Full Text
Peer Reviewed
See detailClimatic and management drivers of CO2 exchanges by a production crop: Analysis over three successive 4-year crop rotation cycles
Buysse, Pauline ULg; Manise, Tanguy ULg; De Ligne, Anne ULg et al

Poster (2016, September 27)

Carbon dioxide (CO2) exchanges between crops and the atmosphere are influenced by both climatic and crop management drivers. The investigated crop, situated at the Lonzée Terrestrial Observatory (LTO ... [more ▼]

Carbon dioxide (CO2) exchanges between crops and the atmosphere are influenced by both climatic and crop management drivers. The investigated crop, situated at the Lonzée Terrestrial Observatory (LTO, candidate ICOS site) in Belgium and managed for more than 70 years using conventional farming practices, was monitored over three complete sugar beet/winter wheat/potato/winter wheat rotation cycles from 2004 to 2016. Continuous eddy-covariance measurements and regular biomass samplings were performed in order to obtain the daily and seasonal Net Ecosystem Exchange (NEE), Gross Primary Productivity (GPP), Total Ecosystem Respiration (TER), Net Primary Productivity (NPP), and Net Biome Production (NBP). Meteorological data and crop management practices were also recorded. Over the 12 years, NEE was negative (-4.34 kg C m-2) but NBP was positive (1.05 kg C m-2), i.e. as soon as carbon exportation by harvest and carbon importation (manure, slimes) are included in the budget, the site behaves as a carbon source. At the crop rotation scale (4 years) it was quite remarkable to observe that NBP was very similar over the three rotations (0.30-0.36 kg C m-2), despite climatic and management differences between years. Crop type impacted carbon exchanges, with sugar beet and winter wheat crops leading to higher net carbon sequestration than seed potato crops. For one given crop, larger growth length and cumulated global radiation drove larger cumulated NEE. Net carbon emissions were observed during intercrops, but growing mustard during these periods reduced their rates and provided carbon residues to the soil. NBP values suggest that one sixth of the total soil organic carbon stock at LTO (6.23 ± 0.16 kg C m-2 in [0, 60] cm) would be lost in 12 years. Large uncertainties (mostly due to biomass measurements) affect NBP estimates, but still, this figure is huge and should encourage cultural practices returning carbon to the soil. [less ▲]

Detailed reference viewed: 25 (2 ULg)
Full Text
Peer Reviewed
See detailOccurrence of greenhouse gases (CO2, N2O and CH4) in groundwater of the Walloon Region (Belgium)
Jurado Elices, Anna ULg; Borges, Alberto ULg; Hakoun, Vivien et al

Conference (2016, September 27)

Carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) can be indirectly transferred to the atmosphere through groundwater discharge into surface water bodies such as rivers. However, these emissions ... [more ▼]

Carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) can be indirectly transferred to the atmosphere through groundwater discharge into surface water bodies such as rivers. However, these emissions are poorly evaluated and highly uncertain. The aim of this work is identify the hydrogeological contexts (alluvial, sandstone, chalk and limestone aquifers) and in situ conditions which are most conducive to the generation and occurrence of GHGs in groundwater at a regional scale. To this end, CO2, CH4 and N2O concentrations as well as major and minor elements were monitored (n=37 samples) in two field campaigns (09/2014 and 03/2015) in 15 groundwater bodies of the Walloon Region (Belgium). This preliminary work, which was presented in the 42st IAH conference (Rome, Italy), shown that GHG concentrations range from 5,160 to 47,544 ppm from the partial pressure of CO2 and from 0 to 1,064 nmol/L and 1 to 5,637 nmol/L for CH4 and N2O respectively. Overall, groundwater was supersaturated in GHGs with respect to atmospheric equilibrium, suggesting that groundwater contribute to the atmospheric GHGs budget. A third sampling campaign is carried out in 2016 including around 60 new groundwater samples. The combination of the results of the three campaigns allows: (1) reducing the uncertainties related to indirect emissions of GHG through groundwater-surface water interaction and (2) contributing to a better understanding of the occurrence of GHGs in aquifers. New results will be presented and discussed in detail in the presentation. [less ▲]

Detailed reference viewed: 33 (2 ULg)
Full Text
See detailMécanismes moléculaires associés à l’induction de la pathogénicité chez Streptomyces scabies
Jourdan, Samuel ULg

Doctoral thesis (2016)

Streptomyces are filamentous soil-dwelling bacteria that actively participate in the mineralization of dead organic matter. Members of this bacterial genus are commonly known for the plethora of secondary ... [more ▼]

Streptomyces are filamentous soil-dwelling bacteria that actively participate in the mineralization of dead organic matter. Members of this bacterial genus are commonly known for the plethora of secondary metabolites of interest they secrete. Predominantly saprophytes, some Streptomyces species have been proved to be phytopathogenic. The most widespread and best characterized of these species is Streptomyces scabies which is the causative agent of the common scab disease that affects the underground organs of many plants with a preference for storage organs such as potato tubers or pivot roots (beet, turnip, carrot, etc.). Common scab is characterized by brown and corky lesions on the infected organs and causes significant economic losses around the world. The pathogenicity of S. scabies is directly related to its ability to produce the phytotoxin thaxtomin. Unveiling when, how and why S. scabies triggers the production of its phytotoxin is therefore of major interest to understand phytopathogenicity and the virulence associated with this bacteria. Previous works identified cellobiose as the main elicitor of thaxtomin production. However, no signaling pathway from the sensing of the eliciting signal to the biosynthesis of thaxtomin has been proposed so far. The aim of this work is to elucidate the molecular mechanisms involved in the onset of thaxtomin production in the model species S. scabies. In this work we highlighted the central role of the cellulose utilization transcriptional repressor CebR in S. scabies pathogenicity. Indeed, we showed that this regulator directly controls the expression of thaxtomin biosynthesis genes, but also the expression of genes involved in sensing, transport and catabolism of cellooligosaccharides. Together, our results allow to propose a first signaling pathway from cellooligosaccharide transport to the production of thaxtomin in S. scabies, with each step of the cascade controlled by CebR. The results obtained in the course of this thesis extended well beyond the fundamental research scope of elucidating the mechanisms associated with the onset of virulence of S. scabies. Indeed, assessed if/how our findings could propose solutions to current industrial biotechnology iapplications, i.e. i) to provide a mutant that constitutively produce thaxtomine could improve the production yields of this promising bioherbicide, and ii) to assess the enzymatic characteristics of a Beta-glucosidase of S. scabies as possible candidate in lignocellulose saccharification processes. [less ▲]

Detailed reference viewed: 40 (5 ULg)
Full Text
See detailInvestir ou mourir, il faut choisir…
Choffray, Jean-Marie ULg

Book published by Amazon, Kindle Edition (2016)

Investir : c’est croire en l’avenir. C’est renoncer en partie au présent pour donner vie au futur. C’est tourner le dos aux « bouffeurs d’espoir » et à l’illusoire confort du statu quo. Enfin, et surtout ... [more ▼]

Investir : c’est croire en l’avenir. C’est renoncer en partie au présent pour donner vie au futur. C’est tourner le dos aux « bouffeurs d’espoir » et à l’illusoire confort du statu quo. Enfin, et surtout, c’est oser « oser » ! La distance séparant le discours public de la performance économique avérée suffit à démontrer l’incompréhension des mécanismes de création de richesse de ceux qui sont censés en avoir la maîtrise et/ou les mettre en œuvre. Il est peu de domaines où les illusions, et autres idées fausses, ont un succès tel qu’elles amènent à s’interroger sur le profit que d’aucuns pourraient en tirer… L’objet de cet ouvrage est de partager le fruit d’une réflexion menée sur le thème de l’investissement, forme proéminente et condition première de l’activité économique, au moment où certains s’interrogent sur son encadrement et cherchent à en limiter la liberté. Il aborde les bouleversements technologiques les plus significatifs ; l’art et la science d’investir avec Internet ; la recherche d’opportunités nouvelles ; et, se termine par quelques observations et souhaits quant à « l’état » du monde ! [less ▲]

Detailed reference viewed: 1216 (118 ULg)
Full Text
See detailOn the GMP production of [18]FUCB-H : Imaging neurotransmission
Warnier, Corentin ULg

Doctoral thesis (2016)

We herein describe the straightforward synthesis of a stable pyridyl(aryl)iodonium salt and its [18F]radiolabelling within a one-step, fully automated and cGMP compliant radi-osynthesis of [18F]UCB-H, a ... [more ▼]

We herein describe the straightforward synthesis of a stable pyridyl(aryl)iodonium salt and its [18F]radiolabelling within a one-step, fully automated and cGMP compliant radi-osynthesis of [18F]UCB-H, a PET tracer for the imaging of Synaptic Vesicle glycoprotein 2A (SV2A). Over the course of one year, 40 automated productions provided 34±2% of injectable [18F]UCB-H from up to 7.7 Ci of [18F]fluoride in 50 minutes (uncorrected radiochemical yield. Specific Activity = 22±5 Ci/µmol). The successful implementation of our synthetic strategy within routine, high-activity and cGMP productions attests to its practicality and reliability for the production of large doses of [18F]UCB-H. In addition to enabling efficient and cost-effective clinical research on a range of neurological pathologies through the imaging of SV2A, this work further demonstrates the real value of iodonium salts in the cGMP 18F-PET tracer manufacturing industry and their ability to fulfill practical and regulatory requirements in that field. [less ▲]

Detailed reference viewed: 42 (8 ULg)
See detailRelectures de La Misère du monde: Bourdieu, Sartre, Enzensberger
Cormann, Grégory ULg

Conference (2016, September 26)

Detailed reference viewed: 17 (0 ULg)
Full Text
See detailL'imagination au travail : Sartre, Marcuse, Negt
Hervy, Alievtina ULg

Scientific conference (2016, September 26)

Detailed reference viewed: 17 (0 ULg)
Peer Reviewed
See detailMUCOADHESIVE SPONGES WITH PEGYLATED LIPOPLEXES: TOWARDS A SUSTAINED VAGINAL DELIVERY OF siRNA
Furst, Tania ULg; Dakwar, Georges; zagato, Elisa et al

Poster (2016, September 26)

Detailed reference viewed: 15 (4 ULg)
Full Text
Peer Reviewed
See detailGroundwater flow and saltwater intrusion modelling in the Continental Terminal (CT) aquifer near the Saloum inverse estuary in Senegal
Faye, Serigne; Ndeye, Maguette Dieng; Orban, Philippe ULg et al

Conference (2016, September 26)

The Saloum River hypersaline estuary (Senegal) is an ‘inverse estuary’ showing a salinity increasing from the river mouth towards inland. This salinization process is mainly driven by a net loss of ... [more ▼]

The Saloum River hypersaline estuary (Senegal) is an ‘inverse estuary’ showing a salinity increasing from the river mouth towards inland. This salinization process is mainly driven by a net loss of freshwater due to intense evaporation. In this context, interactions between the river and the surrounding aquifer of the Continental Terminal (CT) may lead to local and progressive salinization of this groundwater main resource for water supply. Our study, based on available data and new measured data in 2012 and 2013, is focused on the southern part of the Saloum basin. It confirms that the groundwater resource is threatened by local saltwater intrusions in the vicinity of the Saloum River and along the western coastal part of the aquifer. For a long term water resources management, it is thus essential to predict the future evolution of this process in a context of increasing groundwater pumping rate together with climate variability and changes. A groundwater flow model is developed using MODFLOW. Starting from a conceptual steady-state situation corresponding to the CT aquifer state in 1973 before development of pumping, a transient calibration of the groundwater flow model is performed on data from 1974 to 2012. Despite the low number of measured data, the model can be considered as the current best assessment tool for future predictions. Using the particle tracking technique (MODPATH), a first assessment of the saltwater intrusions in the aquifer is simulated (neglecting the density effect on the hydraulic conductivity) confirming the measured data. Results, for an increased pumping of 20% in 2050 combined with different climatic scenarios, are useful to assess how the saltwater intrusions will evolve in the next years. [less ▲]

Detailed reference viewed: 14 (0 ULg)
Full Text
Peer Reviewed
See detailQuelles réponses face à la fatigue vocale? Variabilité inter-individuelle des modifications acoustiques de la voix au cours de la journée
Remacle, Angélique ULg; Gerber, Silvain; Garnier, Maëva

Poster (2016, September 26)

Objectifs: 1) décrire l’évolution de 4 indicateurs acoustiques de la fatigue vocale au cours d’une journée de travail et examiner leur universalité dans l'échantillon, 2) déterminer si différentes ... [more ▼]

Objectifs: 1) décrire l’évolution de 4 indicateurs acoustiques de la fatigue vocale au cours d’une journée de travail et examiner leur universalité dans l'échantillon, 2) déterminer si différentes typologies de réponse à la fatigue vocale peuvent être distinguées. Population: 22 enseignantes enregistrées le matin et le soir après leur journée de travail, à 3 temps de l’année: octobre, décembre, et février. Tâche: voyelle [a] tenue produite 5 fois à intensité et fréquence confortables. Paramètres mesurés avec Praat et moyennés sur les 5 répétitions: F0 (Hz), rapport harmoniques/bruit (HNR, dB), local Jitter (%), et local Shimmer (%). Les variations des moyennes entre le soir et le matin (Δ) sont calculées pour chaque paramètre. Résultats: En accord avec la littérature, le Δ moyen pour les 22 participantes aux 3 temps montre une augmentation de F0 et HNR, et une diminution de Jitter et Shimmer au cours de la journée. Cependant, ces résultats ne sont pas généralisés dans notre échantillon. Une analyse hiérarchique ascendante permet d'identifier 3 typologies de réponse à la fatigue vocale, observées suite à la journée de travail. Typologie 1: tendance inverse à la littérature (ΔF0 et ΔHNR négatifs, Δjitter et Δshimmer positifs). Comportement hypofonctionnel en réponse à la fatigue vocale. Typologie 2: tendance et amplitude similaires à la littérature (ΔF0 et ΔHNR positifs, Δjitter et Δshimmer négatifs). Réponse attendue, adaptation saine à la fatigue vocale. Typologie 3: tendance similaire à la littérature mais d’amplitude très marquée. Comportement hyperfonctionnel, suspicion d’un trouble vocal. [less ▲]

Detailed reference viewed: 26 (4 ULg)
Peer Reviewed
See detailSmall molecule ligands for the orphan GPR27
Dupuis, Nadine ULg; Franssen, Delphine ULg; Laschet, Céline ULg et al

Poster (2016, September 26)

Background G protein-coupled receptors (GPCRs) are involved in many physiological processes and constitute the target of around 30% of marketed therapies. Nonetheless, ~100 human GPCRs have no known ... [more ▼]

Background G protein-coupled receptors (GPCRs) are involved in many physiological processes and constitute the target of around 30% of marketed therapies. Nonetheless, ~100 human GPCRs have no known ligand and are designated as "orphan". This project focuses on GPR27, a rhodopsin-like alpha orphan of the SREB family (Super conserved Receptors Expressed in the Brain), presumably involved in the regulation of insulin secretion [1]. Methods In order to identify small molecules activating GPR27, we developed a firefly luciferase complementation assay (based on [2]) to assess the binding of ß-arrestin2 to the activated GPCR. To increase the affinity for and strengthen the interaction with ß-arrestin2, a GPR27-V2R chimera has been used for library screening. Results Small molecules activating GPR27-V2 have been identified in the DiverSetTM library (ChemBridge). After exclusion of non-specific activities using another unrelated GPCR, two compounds sharing a common scaffold with activity in the low micromolar range were selected for further investigations. We confirmed their agonist profile by performing complete concentration-response curves on our arrestin complementation assay as well as orthogonal assays. These compounds show good specificity being inactive on GPR85-V2 and GPR173-V2 (the two other SREB members). With these original tools, we characterized the recruitment of ß-arrestin2 to activated GPR27 WT. Conclusion We identified small molecule ligands for GPR27 that will serve as valuable tools for studying the pharmacology of GPR27 as well as its physiological roles, for example in insulin secretion. 1 Ku G.M., Pappalardo Z., Luo C.C., German M.S., McManus M.T. An siRNA Screen in Pancreatic Beta Cells Reveals a Role for Gpr27 in Insulin Production. PLoS genetics. 2012, 8, e1002449. 2 Takakura H., Hattori M., Takeuchi M., Ozawa T. Visualization and Quantitative Analysis of G Protein-Coupled Receptor−β-Arrestin Interaction in Single Cells and Specific Organs of Living Mice Using Split Luciferase Complementation. ACS Chem. Biol. 2012, 7, 901−910. [less ▲]

Detailed reference viewed: 34 (3 ULg)
Full Text
Peer Reviewed
See detailLe développement de l’agriculture familiale par les transferts des migrants
Yao Namé, Juste Michel ULg; Lebailly, Philippe ULg

Conference (2016, September 25)

The following pages report the results of our survey conducted among (Malian, Senegalese and Mauritanian) Soninké migrants during the period of 14th to 4 December 2015, living in the social residences of ... [more ▼]

The following pages report the results of our survey conducted among (Malian, Senegalese and Mauritanian) Soninké migrants during the period of 14th to 4 December 2015, living in the social residences of the former home Pinel (first home of migrant workers in France). This survey had to aim to discuss the implementation and use of a new tool to transfer the money in order to reduce use of informal channels, to promote financial inclusion, to finance smallholding and to develop entrepreneurship in rural by granting of credits medium or long term via Microfinance Institutions (IMF). [less ▲]

Detailed reference viewed: 33 (14 ULg)