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See detailImpact of spatio-temporal shade dynamics on wheat growth and yield, perspectives for temperate agroforestry
Artru, Sidonie ULiege; Garré, Sarah ULiege; Dupraz, Christian et al

in European Journal of Agronomy (2017)

A stumbling block to the adoption of silvoarable agroforestry systems is the lack of quantitative knowledge on the performance of different crops when competing for resources with trees. In North-Western ... [more ▼]

A stumbling block to the adoption of silvoarable agroforestry systems is the lack of quantitative knowledge on the performance of different crops when competing for resources with trees. In North-Western Europe, light is likely to be the principal limiting resource for understorey crops, and most agronomic studies show a systematic reduction of final yield as shade increases. However the intensity of the crop response depends on both the environmental conditions and the shade characteristics. This study addressed the issue by monitoring winter wheat (Triticum aestivum L.) growth, productivity and quality under artificial shade provided by military camouflage shade-netting, and using the Hi-sAFe model to relate the artificial shade conditions to those applying in agroforestry systems. The field experiment was carried out over two consecutive years (2013–14 and 2014–15) on the experimental farm of Gembloux Agro-Bio Tech, Belgium. The shade structures recreated two shade conditions: periodic shade (PS) and continuous shade (CS), with the former using overlapping military camouflage netting to provide discontinuous light through the day, and the latter using conventional shade cloth. The experiment simulated shading from a canopy of late-flushing hybrid walnut leaves above winter wheat. Shading was imposed 16 (2013–14) and 10 (2014–15) days before flowering and retained until harvest. The crop experienced full light conditions until the maximum leaf area index stage (LAImax) had been reached. In both years, LAI followed the same dynamics between the different treatments, but in 2013–2014 an attack of the take-all disease (Gaeumannomyces graminis var. tritici) reduced yields overall and prevented significant treatment effects. In season 2014–15 the decrease in global radiation reaching the crop during a period of 66 days (CS: – 61% and PS: – 43%) significantly affected final yield (CS: – 45% and PS: – 25%), mainly through a reduction of the average grain weight and the number of grain per m2. Grain protein content increased by up to 45% under the CS treatment in 2015. Nevertheless, at the plot scale, protein yield (t/ha) did not compensate for the final grain yield decrease. The Hi-sAFe model was used to simulate an agroforestry plot with two lines of walnut trees running either north-south or east-west. The levels of artificial shade levels applied in this experiment were compared to those predicted beneath trees growing with similar climatic conditions in Belgium. The levels used in the CS treatment are only likely to occur real agroforestry conditions on 10% of the cropped area until the trees are 30 years old and only with east-west tree row orientation. [less ▲]

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See detailLe métier d'enseignant : de plus en plus pénible ?
Lafontaine, Dominique ULiege; Quittre, Valérie ULiege

Conference given outside the academic context (2017)

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See detailSocio-historique de la protection sociale en Belgique
Jacquet, Nicolas ULiege

Conference given outside the academic context (2017)

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See detailConstater les dégâts, évaluer les risques, proposer des solutions de lutte contre l'érosion hydrique des sols
Morvan, Xavier; Faucon, Michel-Pierre; Armand, Romain et al

Scientific conference (2017, November 07)

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See detailGeneration of open foam RVEs with sharp edges using Distance fields and Level sets
Kilingar, Nanda Gopala ULiege; Noels, Ludovic ULiege; Massart, Thierry Jacques et al

Conference (2017, November 07)

A methodology to generate Representative Volume Elements for open foam cellular materials based on distance and level set functions is explained. The main focus of this work is to properly represent the ... [more ▼]

A methodology to generate Representative Volume Elements for open foam cellular materials based on distance and level set functions is explained. The main focus of this work is to properly represent the geometry of the sharp edges of the foam struts that are resulting from the solidification phase during manufacturing. An approach to generate RVEs for open-cell foams is described in [1], where arbitrary shaped tessellations are produced and specific combination of distance functions are used to generate open foam RVEs. Steep discontinuities in the distance functions derivatives result in the generation of jagged sharp edges, due to the use of discrete level set functions. The procedure to extract geometries from multiple level set functions to reproduce such sharp edges of the struts proposed in [1] has been incorporated in the current work. The individual cells are extracted as inclusion surfaces based on distance functions. The inclusion surfaces are then modified using multiple level set functions, and the sharp edges are computed from the intersection of these inclusions. The resulting geometry can then be meshed using size functions based on curvature and narrowness and a mesh optimization inspired from [2]. The methodology to produce high quality meshes based on [3] will be outlined (Figure 2). The resulting FE models will be then used in simulations to assess the practical applications of these models by comparing with experimental data of physical samples. [less ▲]

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See detailGeneration of unidirectional composite stochastic volume elements from micro-structural statistical information
Wu, Ling ULiege; Bidaine, Benoit; Major, Zoltan et al

Conference (2017, November 07)

The purpose of this work is to generate Stochastic Volume Element (SVE) of unidirectional composites using statistical information obtained from imaging technique in order to study the effect of the micro ... [more ▼]

The purpose of this work is to generate Stochastic Volume Element (SVE) of unidirectional composites using statistical information obtained from imaging technique in order to study the effect of the micro-structure uncertainty on the meso-scale behavior. When considering a homogenization-based multiscale approach, the material properties are obtained at each integration point of a macro-structure from the resolution of a micro-scale boundary value problem. When the separation of scales holds, the macro-point is viewed at the micro-level as the center of a Representative Volume Element (RVE). However, for composite materials which suffer from a large scatter in their constituent properties and microstructure, the separation of scales does not always hold, in particular at the onset of failure, and structural properties exhibit a scatter. In order to predict this scatter, Stochastic Volume Elements (SVE) [1, 2] of unidirectional fiber composite materials should be built from experimental measurements, see Fig. 1(a). Toward this end, statistical functions of the fibers features such as radius, the closest neighboring distance etc. [3] are extracted from several SEM images to generate statistical functions of the micro-structure. The dependent variables are then represented using the copula framework, allowing generating micro-structures, see Fig. 1(b), using an inclusions additive process. Simulations on the generated SVEs are then used to extract the probabilistic meso-scale stochastic behavior. In the future the extracted behaviors will be used to build a stochastic model of homogenized properties based on Mean-Field-Homogenization in order to predict statistical macro-scale behaviors and in particular the failure onset. References [1] Ostoja-Starzewski, M., Wang, X. Stochastic finite elements as a bridge between random material microstructure and global response. Comput. Meth. in Appl. Mech. and Eng. (1999) 168: 35-49. [2] Lucas, V., Golinval, J.-C., Paquay, S., Nguyen, V.-D., Noels, L., Wu, L. A stochastic computational multiscale approach; Application to MEMS resonators. Comput. Meth. in Appl. Mech. and Eng. (2015) 294, 141-167. [3] Vaughan, T.J., McCarthy C.T. A combined experimentalnumerical approach for generating statistically equivalent fibre distributions for high strength laminated composite materials. Compos. Sci. and Tech. (2010) 70, 291-297. [less ▲]

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See detailA stochastic 3-scale method to predict the thermo-elastic behaviors of polycrystalline structures
Wu, Ling ULiege; Lucas, Vincent; Golinval, Jean-Claude ULiege et al

Conference (2017, November 07)

The purpose of this work is to upscale material uncertainties in the context of thermo-elastic response of polycrystalline structures. The probabilistic behavior of micro-resonators made of ... [more ▼]

The purpose of this work is to upscale material uncertainties in the context of thermo-elastic response of polycrystalline structures. The probabilistic behavior of micro-resonators made of polycrystalline materials is evaluated using a stochastic multi-scale approach defined using the following methodology. 1. Stochastic volume elements (SVEs) [1] are defined from Voronoi tessellations using experimental measurements of the grain size, orientation, and surface roughness [2]; 2. Mesoscopic apparent thermo-elastic properties such as elasticity tensor, thermal conductivity tensor, and thermal dilatation tensor are extracted using a coupled homogenization theory [3, 4] applied on the SVE realizations; 3. A stochastic model of the homogenized properties extracted from Voronoi tessellations using a moving window technique is then constructed in order to be able to generate spatially correlated meso-scale random fields; 4. These meso-scale random fields are then used as input for stochastic finite element simulations. As a result, the probabilistic distribution of micro-resonator properties can be extracted. The applications are two-fold: 1. A stochastic thermo-elastic homogenization, see Fig. 1(a), is coupled to thermoelastic 3D models of the micro-resonator in order to extract the probabilistic distribution of the quality factor of micro-resonators [5]; 2. A stochastic second-order mechanical homogenization, see Fig. 1(b), is coupled to a plate model of the micro-resonator in order to extract the effect of the uncertainties related to the surface roughness of the polycrystalline structures [2]. References [1] Ostoja-Starzewski, M., Wang, X. Stochastic finite elements as a bridge between random material microstructure and global response. Comput. Meth. in Appl. Mech. and Eng. (1999) 168: 35-49. [2] Lucas, V., Golinval, J.-C., Voicu, R., Danila, M., Gravila, R., Muller, R., Dinescu, A., Noels, L., Wu, L. Propagation of material and surface profile uncertainties on MEMS micro-resonators using a stochastic second-order computational multi-scale approach. Int. J. for Num. Meth. in Eng. (2017). [3] Temizer, I., Wriggers, P. Homogenization in finite thermoelasticity.J. of the Mech. and Phys. of Sol. (2011) 59, 344-372. [4] Nguyen, V. D., Wu, L., Noels, L. Unified treatment of boundary conditions and efficient algorithms for estimating tangent operators of the homogenized behavior in the computational homogenization method. Computat. Mech. (2017) 59, 483-505. [5] Wu, L., Lucas, V., Nguyen, V. D., Golinval, J.-C., Paquay, S., Noels, L. A Stochastic Multi-Scale Approach for the Modeling of Thermo-Elastic Damping in Micro-Resonators. Comput. Meth. in Appl. Mech. and Eng. (2016) 310, 802-839. [less ▲]

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See detailCharacterization and regulation of the intestinal epithelial cell response to colitogenic triggers
El Abbas, Sophie ULiege; Beguin, C; Schyns, Joey ULiege et al

in Proceedings of Annual meeting of the French Society for Immunology (SFI) (2017, November 07)

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See detailEcophysiology of elephants to better understand their crop selection: first results of a case study in Monts de Cristal, Gabon
Ngama, Steeve ULiege

Conference (2017, November 07)

Parasites and hormones are one of the best indicators of animal ecophysiology which clarify the role and importance of physiological processes in the ecological relations of species in their natural ... [more ▼]

Parasites and hormones are one of the best indicators of animal ecophysiology which clarify the role and importance of physiological processes in the ecological relations of species in their natural habitat. As damages on crops are often sources of conflict between humans and elephants in elephant home ranges, few data on the relevance of elephant physiology on crop selection exist. For that we investigate elephant ecophysiology to better understand if their parasitism and stress conditions underlie their crops selection. For that we measured parasite loads and stress hormone levels in feces of some elephants eating banana and others eating natural food. We conducted the study during fifteen months covering five different local seasons of the research site in Mont de Cristal, Gabon. Here we report first results from two seasons. We collected 485 samples of elephant dungs and more than 1200 samples of food items eaten by elephants. While stress levels are not correlated to banana selection, the presence of parasites is. Our results show higher parasite loads in dungs of elephants eating banana than in those of elephants eating natural food resources species. Thus elephants may eat banana more as a medicine item than a food resource. But we still need to confirm these results by assessing this trend over seasons and with reproduction hormones. [less ▲]

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See detailGreenland Ice Sheet Surface Mass Loss: Recent Developments in Observation and Modeling
van den Broeke, M.; Box, J.; Fettweis, Xavier ULiege et al

in Current Climate Change Reports (2017)

Surface processes currently dominate Greenland ice sheet (GrIS) mass loss. We review recent developments in the observation and modeling of GrIS surface mass balance (SMB), published after the July 2012 ... [more ▼]

Surface processes currently dominate Greenland ice sheet (GrIS) mass loss. We review recent developments in the observation and modeling of GrIS surface mass balance (SMB), published after the July 2012 deadline for the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC AR5). Since IPCC AR5, our understanding of GrIS SMB has further improved, but new observational and model studies have also revealed that temporal and spatial variability of many processes are still poorly quantified and understood, e.g., bio-albedo, the formation of ice lenses and their impact on lateral meltwater transport, heterogeneous vertical meltwater transport (‘piping’), the impact of atmospheric-circulation changes and mixed-phase clouds on the surface energy balance, and the magnitude of turbulent heat exchange over rough ice surfaces. As a result, these processes are only schematically or not at all included in models that are currently used to assess and predict future GrIS surface mass loss. [less ▲]

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See detailDevelopment of an Interferometric Mass Processing Chain for Multitemporal Ground Deformation Measurements
Libert, Ludivine ULiege; De Rauw, Dominique ULiege; d'Oreye, Nicolas

Conference (2017, November 07)

The main goal of the RESIST project is to understand the mechanisms driving volcanic eruptions and landslides in the Kivu region, on the East African Rift. In order to model both volcanic and landslide ... [more ▼]

The main goal of the RESIST project is to understand the mechanisms driving volcanic eruptions and landslides in the Kivu region, on the East African Rift. In order to model both volcanic and landslide processes, it is necessary to measure ground deformations in the region accurately. For this purpose, both ground-based instruments (e.g. GPS network) and spaceborne data (e.g. optical and SAR images) are used. One aspect of the project focuses on Differential SAR Interferometry (DInSAR), which is a technique used to map ground deformations occurring between two SAR images acquired at different times. It is today a well-mastered technique that offers large spatial coverage with a typical temporal sampling of one to several days, depending on the chosen sensor. In the last years, multitemporal approaches based on DInSAR have been developed, like the Small BAseline Subset (SBAS) [1] and Multidimensional Small BAseline Subset (MSBAS) [2] techniques, or the Persistent Scatterers Interferometry (PSI) [3]. In the framework of RESIST, we use MSBAS to perform ground deformations monitoring along time. The Multidimensional Small BAseline Subset (MSBAS) technique produces 2-D time series of ground deformations by integrating data sets of SAR images acquired by different sensors, with different spatial and temporal sampling, resolutions, incidence angles, wavelengths, pass directions and other varying parameters. By combining at least two data sets with overlapping spatial and temporal coverage and an extended range of look angles, the evolution of deformations in the vertical and west-east directions can be computed by the MSBAS approach [2]. The MSBAS software feeds on a large amount of deformation maps, which are produce by DInSAR. Such an amount of data cannot be produced by hand and that is the reason why we developed an automatic interferometric processing chain meant to produce large amounts of products adequate for multitemporal methods like MSBAS. The interferometric processing is supported by the CSL InSAR Suite (CIS) software developed at Centre Spatial de Liège, which presents the advantages to be fully adaptable to the needs of the MSBAS technique and the thematic specificities. Indeed, numerous options (e.g. adaptive filtering, wide swath interferometry) have been added to the CIS software in the framework of the RESIST project. In a first time, we will briefly present the MSBAS approach and its advantages regarding the ground deformation measurements. In the second part of the presentation, we will introduce the mass processing chain step by step and its functionalities. Critical steps of the chain, like the chosen strategy for the interferometric pairs selection, the integration of Sentinel-1 data or the image interpolation approach, will be presented in more details. Finally, preliminary results of an MSBAS processing over the Bukavu area will be presented. REFERENCES: [1] Berardino, P., Fornaro, G., Lanari, R., and Sansosti, E. (2002). A new algorithm for surface deformation monitoring based on small baseline differential SAR interferograms, IEEE Trans. Geosci. Remote Sens., 40, 11, pp. 2375-2383. doi: 10.1109/TGRS.2002.803792. [2] Samsonov, S., and d’Oreye, N. (2012). Multidimensional time series analysis of ground deformation from multiple InSAR data sets applied to Virunga Volcanic Province, Geophysical Journal International, 191, 3, pp. 1095-1108. doi: 10.1111/j.1365-246X.2012.05669.x [3] Ferretti, A., Prati, C., and Rocca, F. (2001). Permanent scatterers in SAR interferometry, IEEE Trans. Geosci. Remote Sens., 39, 1, pp. 8-20. doi: 10.1109/36.898661. [less ▲]

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See detailAura-t-on toujours besoin de chômeurs en 2030 ?
Orianne, Jean-François ULiege

Scientific conference (2017, November 07)

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See detailA TMS–EEG contribution to the multimodal assessment of brain connectivity and consciousness
BODART, Olivier ULiege

Doctoral thesis (2017)

Patients with chronic disorders of consciousness make a challenging population. On the clinical side, establishing an accurate diagnosis is arduous, as the signs of consciousness can be subtle, or even ... [more ▼]

Patients with chronic disorders of consciousness make a challenging population. On the clinical side, establishing an accurate diagnosis is arduous, as the signs of consciousness can be subtle, or even undetectable behaviourally. Both the families and the caregivers need truthful information to make tough decisions about the patient’s management. Transcranial magnetic stimulation, coupled with high-density electroencephalography, is a promising technique to improve our diagnostic ability. The perturbational complexity index derived from this technique is able to distinguish between unconscious and conscious conditions. Its specificity remains to be determined. On the scientific side, the long-standing quest to discover the neural correlates of consciousness is still ongoing. Patients with disorders of consciousness have structural brain damage, and several areas may lose their ability to causally interact in complex patterns with long distance structure. The relation between this ability and structural integrity remains undetermined, despite a vast amount of neuroimaging studies on several networks and connectivities in this population. Our objectives are i) to cross-validate the perturbational complexity index with other neuroimaging techniques, and to determine its specificity, and ii) to determine the relation between global structural integrity and the brain global ability to sustain complex long-range interactions. To do so, we first combined transcranial magnetic stimulation with fluoro-deoxyglucose positron emission tomography, a validated technique studying the brain metabolism, in a population of patients behaviourally characterized by repeated assessments with the gold standard scale, the coma recovery scale – revised. To meet our second objective, we computed and compared the perturbational complexity index and the global fractional anisotropy, a magnetic resonance imaging marker of structural integrity, in patients and in healthy subjects. We found an excellent congruence between electrophysiological and metabolic results in our first study, even in behaviourally unconscious patients showing indirect signs of consciousness. In our second study, we demonstrated that structural integrity largely correlated with the perturbational complexity index, and did not depend on the time since onset or the aetiology. This confirms the diagnostic value of transcranial magnetic stimulation and the perturbational complexity index. It is not only sensitive at the single subject level, but also highly specific. It can detect covert signs of consciousness, as confirmed by other neuroimaging techniques. As such, it could be integrated in diagnostic algorithms and improve their accuracy, leading to better management of these patients. Moreover, the brain’s ability to sustain complex long-range interactions is highly dependant on the global structural integrity. By looking further in detail at the local correlation between these two parameters, our understanding of the emergence of consciousness from fixed structure with variable connectivity would improve. This would be one step forward in the quest for the neural correlates of consciousness. [less ▲]

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See detailElectrification and DRC
Ernst, Damien ULiege

Conference given outside the academic context (2017)

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See detailPictorial scale of perceived water competences The building of a new tool adapted to the children
Jidovtseff, Boris ULiege; De Sousa Morgado, Liliane ULiege; Sääkslahti, Arja et al

Conference (2017, November 07)

Introduction Researches have demonstrated the interest to develop pictorial instrument for assessing fundamental movement skill perceived competence in young children (1). Perceived competence appears ... [more ▼]

Introduction Researches have demonstrated the interest to develop pictorial instrument for assessing fundamental movement skill perceived competence in young children (1). Perceived competence appears appear at least as important as actual competence as it may more directly affect motivation towards an active behavior (2). For different reasons, it is worth developing such a pictorial instrument for assessing children’s perceived water competencies. With that aim, a collective of researchers have decided to work on the development of such a new tool. Methods The collective of researcher started in 2016 during AIESEP congress in Laramie (USA) and grew up by including additional experts specialized in aquatic skill and/or pictorial scale tools. Videos skype conference and email exchanges were used for communication. Important discussions and decisions concerned the list of aquatic competence skills, the scoring system, the selection of an illustrator and the characteristics of the pictures. In order to build the tool within a reasonable delay, timing with the different actions has been suggested. Results A first list of water competencies has been dressed based on scientific references (3-5). According to these skills, different practical situation have been selected to be included in the pictorial scale. The collective of researcher decided to start with a three level score system including ‘not able’, ‘in progression’ and ‘able’ pictures for each situation. All pictures must be digital in such a way they could be used on paper and/or on computer and android/apple applications. Pictures have to be neutral and to be representative of different cultures and contexts in order to be adapted to all countries and situations. The possibility of having the same image in different cultural contexts is investigated. The different steps in the scale development have been scheduled and will include: content validity, face validity, construct validity, reliability, data collection. Conclusion The development of a pictorial instrument for assessing children perceived water competencies is progressing well and a usable version of the tool should be available by the end of 2017 References 1. Barnett, L. M., Ridgers, N. D., Zask, A., & Salmon, J. (2015). Face validity and reliability of a pictorial instrument for assessing fundamental movement skill perceived competence in young children. Journal of science and medicine in sport, 18(1), 98-102. 2. Barnett, L. M., Morgan, P. J., van Beurden, E., & Beard, J. R. (2008). Perceived sports competence mediates the relationship between childhood motor skill proficiency and adolescent physical activity and fitness: a longitudinal assessment. International journal of behavioral nutrition and physical activity, 5(1), 40. 3. Langendorfer, S. J., & Bruya, L. D. (1995). Aquatic readiness: Developing water competence in young children. Human Kinetics 1. 4. Langendorfer (2015). Changing Learn-to-Swim and Drowning Prevention Using Aquatic Readiness and Water Competence, International Journal of Aquatic Research and Education, 2015, 9, 4-11 5. Quan et al. (2015). Toward Defining Water Competency: An American Red Cross Definition, International Journal of Aquatic Research and Education, 2015, 9, 12-23 [less ▲]

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See detailMeasuring children motor skills with MOBAK-1: criteria adaptation and comparison of two scoring systems
Jidovtseff, Boris ULiege; Paulus, Camille ULiege; De Sousa Morgado, Liliane ULiege

in Electronic Abstract book AIESEP 2017 (2017, November 07)

Introduction The MOBAK-1 testing battery has been recently developed with the aim of assessing the locomotion and object-control abilities of first grade children. Previous researches have demonstrated ... [more ▼]

Introduction The MOBAK-1 testing battery has been recently developed with the aim of assessing the locomotion and object-control abilities of first grade children. Previous researches have demonstrated the global interest of this testing battery (1,2). However, a critical analysis of children failures in the tests revealed that some failures were related to the misunderstanding of the instruction or to unsuitable criteria and not to children inability (2). Moreover, the discrimination of the scoring system was also questioned. The aim of the study is to improve criteria in order to avoid the failure that are not related to children ability and to compare the actual dichotomous scoring system with another scoring system taking in consideration the progression of the children. Methods The MOBAK-1 testing battery will be addressed to 30 first grade children. Criteria for each test will be adapted according to previous observations (2) and will include familiarization with the task and additional trial when it is clear that the failure is not due to children ability. All the children will be assessed at the same time with the actual dichotomous scoring system and with an original scoring system that takes the children level of development into account. Results We hypothesized that the adaptation of the criteria will improve the testing battery discrimination. We also expected that the scoring system based on children progression will be more accurate but will be more difficult to be used by unexperienced teachers. Conclusion According to the results of the study, concrete improvements will be addressed to the researchers who work on MOBAK testing battery development. References 1. Herrmann, C., Gerlach, E., & Seelig, H. (2015). Development and validation of a test instrument for the assessment of basic motor competencies in primary school. Measurement in Physical Education and Exercise Science, 19(2), 80-90. 2. Jidovtseff B., Vandeloise V., Cloes M., Morgado L., Mornard M. (2017). Measuring children motor skills with MOBACK-1: descriptive data and critical analysis Book of abstracts. CIAPSE 2017. Finland. [less ▲]

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See detailSolvent Extraction Design for Highly Viscous Systems
Quaresima, Maria Chiara ULiege; Schmidt, Markus; Pfennig, Andreas ULiege

Conference given outside the academic context (2017)

The change from fossil-based feedstock to bio-based raw materials will lead to changes in the molecular structure of reagents used in the chemical industry. Bio-based raw materials are richer in oxygen ... [more ▼]

The change from fossil-based feedstock to bio-based raw materials will lead to changes in the molecular structure of reagents used in the chemical industry. Bio-based raw materials are richer in oxygen, leading to intermediates and products rich in oxygen as well. This will lead to lower vapor pressure and higher viscosity of the systems. Thus liquid-based separations like solvent extraction will increase in importance. Also separation-process design needs to be adapted to properly account for higher viscosities. With drop-based simulation, extraction-column performance can be predicted to better than 10% accuracy, being time and resources saving compared to pilot-plant experiments. In previous work, appropriate models describing all drop phenomena like sedimentation and mass transfer were combined in a simulation tool, called ReDrop (REpresentative DROPs). The models implemented in ReDrop have been largely validated for low-viscous systems. In order to extend the capabilities of ReDrop and describe the entire viscosity range, models have to be tested for a variety of different material system with single-drop lab-scale experiments. In this work mass transfer has been evaluated with single-drop experiments for two systems with different viscosity. The first one is the standard EFCE system composed by water + acetone + butyl acetate. Results were compared with the mass-transfer evaluation for the aqueous two-phase system with higher viscosity composed by water and PEG + albumine + water and phosphate. The results show that the transport of a component between two immiscible phases is strongly influenced by the viscosity of both phases as well as the molecular size of the transferred component. The single-drop results are the basis for validation and extending the applicability of existing models to higher viscosity, which are then introduced into ReDrop. [less ▲]

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See detailERα- and dose-dependent effect of estetrol on angiogenesis and tumor growth
Gallez, Anne ULiege; BLACHER, Silvia ULiege; Gérard, Céline et al

Poster (2017, November 07)

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See detailThe 4th power
George, Philippe ULiege

Scientific conference (2017, November 06)

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See detailPhotographies clandestines. Les images de la RAF en prison(s).
Hamers, Jérémy ULiege

Scientific conference (2017, November 06)

Detailed reference viewed: 14 (0 ULiège)