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See detailDer Einfluss der Historischen Rechtsschule auf Belgien
Gerkens, Jean-François ULg

Conference (2014, September 12)

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See detailJupiter’s magnetopause: A search for wave and reconnection signatures
Bonfond, Bertrand ULg; Kivelson, M. G.; Khurana, K. K. et al

Conference (2014, September 12)

Surface waves and magnetic reconnection are two key processes taking place at the planetary magnetopause. They allow the coupling, through energy (and particle) transfer, of the interplanetary medium and ... [more ▼]

Surface waves and magnetic reconnection are two key processes taking place at the planetary magnetopause. They allow the coupling, through energy (and particle) transfer, of the interplanetary medium and the magnetosphere. The relative importance of large scale Dungey reconnection and viscous interaction (including small-scale intermittent reconnection associated with Kelvin-Helmholtz vortices) are expected to be different at Jupiter compared to the Earth’s case. Such differences would be due to the combination of a) a weaker solar wind pressure and Alfvén velocity as the distance to the Sun increases, b) a high-β plasma sheet, originating from Io’s outgassing, which inflates the Jovian magnetosphere, c) the rapid rotation of the planet relative to its size (e.g. Desroche et al. 2012). Here we analyse the signatures of wave activity and reconnection on the magnetopause of Jupiter, based on magnetic field and energetic particle measurements from the successive spacecraft that explored the Jovian system. Up to now, 7 spacecraft equipped with a magnetometer have crossed the Jovian magnetopause: Pioneer 10, Pioneer 11, Voyager 1, Voyager 2, Ulysses, Galileo and Cassini. We make use of several normal direction finding techniques, such as the Minimum Variance Analysis, in order to identify waves and Kelvin-Helmholtz vortices. As far as the reconnection is concerned, small scale signatures of flux-tube events (FTEs) had been identified by Walker and Russell (1985), based on a limited data-set from the Pioneers’ and Voyagers’ fly-bys. Here we will extend this search to the extensive dataset from all the missions that explored Jupiter’s system. [less ▲]

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See detailPREVENTION OF INCISIONAL HERNIA AFTER MIDLINE LAPAROTOMY FOR ABDOMINAL AORTIC ANEURYSM TREATMENT: A RANDOMIZED CONTROLLED TRIAL
Muysoms, F; Vierendeels, T; Huyghe, M et al

Conference (2014, September 11)

Background: The incidence of incisional hernias (IH) after open abdominal aortic aneurysm (AAA) repair is high. Prophylactic mesh augmentation (PMA) during laparotomy closure has been proposed in high ... [more ▼]

Background: The incidence of incisional hernias (IH) after open abdominal aortic aneurysm (AAA) repair is high. Prophylactic mesh augmentation (PMA) during laparotomy closure has been proposed in high-risk patients. Methods: A multicenter prospective randomized controlled study was conducted on patients undergoing elective repair of AAA through midline laparotomy (Clinical.Trials.gov: NCT00757133). In the study group a retro-muscular PMA was performed with a large-pore polypropylene mesh (Ultrapro™, width 7.5 cm). The primary endpoint was the incidence of IH at 24 months. Results: Between February 2009 and January 2013, 120 patients were recruited at 8 Belgian centers. Patients' characteristics at baseline were similar between the groups. Operative and postoperative characteristics showed no difference in morbidity or mortality. A highly significant reduction of IH incidence was found after PMA compared to conventional closure, respectively 0% (CI: 0 % - 5.5%) versus 27.6% (CI: 16.7% - 40.9%) (P<0.0001; Fisher's exact test). The estimated "freedom of IH" curves (Kaplan-Meier estimate) were significantly different across study arms (X2=18.93, P<0.0001; Mantel-Cox test). No adverse effects were observed, apart from an increased mean (SD) time to close the abdominal wall for PMA: 46.2 min (18.6) versus 29.6 min (18.5) (P<0.001; Mann-Whitney U test). Conclusion: Prophylactic retro-muscular mesh augmentation of a midline laparotomy in AAA patients is safe and effectively prevents the development of IH, with an extra time investment of 17 minutes. [less ▲]

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See detailHighlights of the 2014 Jupiter observing campaign by multi - spectral remote sensing using space telescopes
Kimura, T.; Badman, S.; Tao, C. et al

Conference (2014, September 11)

From January to April 2014, two observing campaigns by multi-wavelength remote sensing from X-ray to radio were performed to uncover energy transport process in Jupiter’s plasma environment using space ... [more ▼]

From January to April 2014, two observing campaigns by multi-wavelength remote sensing from X-ray to radio were performed to uncover energy transport process in Jupiter’s plasma environment using space telescopes and ground-based facilities. These campaigns were triggered by the new Hisaki spacecraft launched in September 2013, which is an extremely ultraviolet (EUV) space telescope of JAXA designed specifically for planetary observations. In the first campaign in January, Hubble Space Telescope made imaging of far ultraviolet (FUV) aurora with a high special resolution (0.08”) through two weeks while Hisaki continuously monitored aurora and plasma torus emissions in EUV wavelength with a high temporal resolution (1 min<). We discovered new magnetospheric activities from the campaign data: e.g., internally-driven type auroral brightening associated with hot plasma injection, and plasma and electromagnetic filed modulations in the inner magnetosphere externally driven by the solar wind modulation. The second campaign in April was performed by Chandra X-ray Observatory, XMM newton, and Suzaku satellite simultaneously with Hisaki. Relativistic auroral accelerations in the polar region and hot plasma in the inner magnetosphere were captured by the X-ray space telescopes simultaneously with EUV monitoring of aurora and plasma torus. In this presentation, we show remarkable scientific results obtained these campaigns mainly focusing on Jupiter’s aurora. [less ▲]

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See detailWeakening of Jupiter’s main auroral emission in response to magnetospheric hot plasma injections
Badman, Sarah; Bonfond, Bertrand ULg; Fujimoto, M. et al

Conference (2014, September 11)

We present images of Jupiter’s northern UV aurorae taken by the Hubble Space Telescope as part of a large observing campaign in January 2014. The high time resolution observations allow the dynamics of ... [more ▼]

We present images of Jupiter’s northern UV aurorae taken by the Hubble Space Telescope as part of a large observing campaign in January 2014. The high time resolution observations allow the dynamics of the different components of the aurorae to be observed. Particular features of interest are large regions of diffuse emission, which occurred equatorward of the main oval, enveloping the auroral footprint of Ganymede. These diffuse, low latitude emissions are caused by the injection of hot plasma from the outer magnetosphere, a process which has previously been related to interchange between the flux tubes from the outer magnetosphere and outward-moving flux tubes loaded with iogenic plasma. Over the two-week observing interval the auroral signatures of two large injection events were observed, while the main oval generally decreased in intensity. We suggest that the overall dimming of the main oval results from the weakening of the corotation-enforcement currents that drive the main emission, following the replacement of the radially-stretched, mass-loaded flux tubes by more dipolar flux tubes containing rarefied hot plasma. [less ▲]

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See detailRANS and Large Eddy Simulation of the hydrodynamics inside mini-bioreactors designed for stem cell culture
Collignon, Marie-Laure ULg; Martin, Céline; Blanchard, Fabrice et al

Conference (2014, September 07)

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See detailCannabis use initiation among adolescents: the predictive role of peers, alcohol, expectancies and internalizing factors.
Schmits, Emilie ULg; Mathys, Cécile ULg; Quertemont, Etienne ULg

Conference (2014, September 05)

Theoretical background: Cannabis is the most commonly used illicit drug among teenagers. Initiation is influenced by environmental factors and personal characteristics, events or experiences. An early ... [more ▼]

Theoretical background: Cannabis is the most commonly used illicit drug among teenagers. Initiation is influenced by environmental factors and personal characteristics, events or experiences. An early initiation increases the risks of problems related to cannabis use (e.g. negative psychosocial effects, delinquent behaviors, mental disorders). Prevent initiation, through the identification of risk/protective factors and their interaction, seems crucial in terms of public health. Research question and significance: This study aimed to examine the progression of use, to identify protective and risk factors of cannabis initiation (including peers, alcohol, expectancies and internalizing factors) and to specifically focus on the influence of social anxiety and its moderators/mediators. Methods: A questionnaire was administered twice to 877 teenagers (49.94% female, M=15.61) with one year interval. Sex, age, demographic variables, peer cannabis use, cannabis-related variables (lifetime, frequency, problems and expectancies), alcohol use, social anxiety, trait-anxiety and depression were assessed through validated scales. Logistic regressions, mediation and moderation analyzes were performed. Results: During the follow-up period, 12.89% of the young participants initiated cannabis use. Several factors significantly predict initiation: alcohol use, peer users, perceptual enhancement and craving effect expectancies. Others factors significantly protect from initiation: negative behavioral effect expectancies and social anxiety. Gender, age, relaxation/social facilitation and cognitive impairment effect expectancies, trait-anxiety and depression do not significantly influence cannabis use initiation. In moderated mediation model, after controlling for relevant variables, social anxiety protected from initiation trough the mediating role of perceptual enhancement and craving effect expectancies. The number of peer users and alcohol use do not moderate this mediation. Negative behavioral effect expectancies do not significantly mediate the relation between social anxiety and cannabis initiation. Interpretation of findings: Through low positive expectancies, adolescents with social anxiety symptoms are less likely to initiate cannabis use than the others, whatever the number of peer users and the alcohol use. Findings are discussed in terms of risk and protective characteristics of relevant factors, in an overall and evolutionary approach including internalizing factors. Results support the identification of internalizing profile of adolescents concerned by prevention or treatment and the importance of social anxiety and expectancies in intervention. [less ▲]

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See detailIs Geometallurgy Teachable? A challenge for the new Erasmus Mundus EMerald
Pirard, Eric ULg

Conference (2014, September 05)

designate any kind of advanced ore characterisation prior to mineral processing operations while in fact it should clearly refer to a multidisciplinary integration of geological, mining, metallurgical ... [more ▼]

designate any kind of advanced ore characterisation prior to mineral processing operations while in fact it should clearly refer to a multidisciplinary integration of geological, mining, metallurgical, environmental and economic information into a single orebody model. In order to instil the best available geometallurgical practices in the professional world, it seems essential to break the traditional cleavages among disciplines and educate a new generation of engineers. The Erasmus Mundus EMerald “Master in Georesources Engineering” program initiated by four European universities under the coordination of University of Liege, has been designed to exactly tackle this challenge. It is not surprising that this program has been set up by universities having a long tradition in mixing a double perspective of geology and engineering (Nancy; Lulea; Liege and Freiberg). Geometallurgy requires both an excellent understanding of the natural variability and complexity of an ore and a comprehensive overview of the techniques available to extract and concentrate any valuable material. The course program has been designed to achieve a right balance between knowledge of mineral resources (geology, resource characterisation, reserve estimation, modelling) and processing (comminution, preconcentration, leaching, waste disposal,...). It also includes a broader view on life cycle analysis and urban mining. A series of professional seminars, suggested by an industrial advisory board, shed light on strategic issues, economic and environmental challenges, corporate social responsibilities, etc. Mobility and multicultural experience is an added-value of the Erasmus Mundus experience which definitely contributes to breeding engineers for tomorrow. [less ▲]

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See detailx
Dodeigne, Jérémy ULg

Conference (2014, September 04)

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See detailTeaching Practices in Science: a Survey of Primary Teachers in the French Speaking Community of Belgium
Quittre, Valérie ULg; Meyer, Coralie; Monseur, Christian ULg

Conference (2014, September 04)

Since PISA 2000, the performance of 15 year-old students from French speaking Community of Belgium (FWB) in science is largely below the OECD average (OECD, 2002, 2004, 2007, 2010 and 2013). This low ... [more ▼]

Since PISA 2000, the performance of 15 year-old students from French speaking Community of Belgium (FWB) in science is largely below the OECD average (OECD, 2002, 2004, 2007, 2010 and 2013). This low level of performance is not really unexpected as it was already observed at grade 7 and grade 8 in TIMSS 1995 (Harmon, Smith & Martin, 1997). In mathematics and in reading, the average performance of the 15 year-olds do not significantly differ from the OECD mean. Can these differences in performance in comparison with the OECD means be partly attributed to the emphasis and importance of the respective intended and implemented curricula? Does the relative importance of science teaching differ between primary and secondary education? In this investigation, we make the assumptions that the problem already exists in primary education and persists in secondary education. Therefore, we will focus on primary education. Data will be mainly collected on opportunities to learn (OTL) for science education and on professional knowledge and teaching practices More precisely, these study intents to question teachers at grade 3 and grade 4 about their beliefs and practices in science. Do the primary teachers feel confident and comfortable with science knowledge and science teaching? What’s the effective learning time of our pupils in science? Can we identify patterns of teachers that current international research has shown to have a significant role in science education of pupils? [less ▲]

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See detailPhysiopathology of cerebral palsy
VIELLEVOYE, Renaud ULg

Conference (2014, September 03)

Cerebral palsy describes a group of disorders of the development of movement and posture, causing activity limitation, that are attributed to nonprogressive disturbances that occurred in the developing ... [more ▼]

Cerebral palsy describes a group of disorders of the development of movement and posture, causing activity limitation, that are attributed to nonprogressive disturbances that occurred in the developing fetal or infant brain. The vulnerability of different brain structures and types of disability associated with CP are influenced by the gestational age at which brain development is altered. Understanding the pathophysiology of CP is crucial for the development of neuroprotective strategies. In the first trimester of gestation, genetic disorders, infectious and toxic diseases explain the vast majority of lesions. In the preterm newborn, neuroinflammation and anoxo-ischemia induce activation of the microglia and a maturational blockade of oligodendrocytes disrupting the developmental program of white matter. In term infants, hypoxic-ischemic encephalopathy is the consequence of the excitotoxic cascade leading to cortical and/or basal ganglia lesions. Clinical disabilities are the consequence of these lesions modulated by cerebral plasticity process. [less ▲]

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See detailCost monitoring to promote the value added for clam raising farmers in the Northern area of Vietnam
Bui Thi, Nga; Tran Thu, Hoai; Tran Huu, Cuong et al

Conference (2014, September 02)

Clam farming in coastal provinces of Vietnam has notably developed since the last decade. It generated high income, improve socio-economic development for many local communities. However, many clam ... [more ▼]

Clam farming in coastal provinces of Vietnam has notably developed since the last decade. It generated high income, improve socio-economic development for many local communities. However, many clam raising farms are facing difficulties of farm management, disease control, markets and systems of quality control. This research aims to study about the real situation of cost monitoring in the clam raising farms in the Northern area of Vietnam and suggest some recommendation for apply a suitable model for cost monitoring to promote the value added for farmers. The paper based on the semi-structure, standard questionnaires and PRA method to collect data from 89 clam raising farms in two coastal provinces (Nam Dinh and Thai Binh) in the Northern area of Vietnam in 2014. The findings show that clam raising provides farmers a chance of getting high income parallel with high risk. There were 32.15% surveyed farms got profit, 32.14% of them met the breakeven and 35.71% was lost. The study finds out four key factors affecting farms’ economic performance and efficiency. The first is capacity of farm cost control as the cost for clam raising was very high at 8,142 to 9,190 USD per ha. The second is the farmers’ experience, skill, technique and ability of risk control. The third is low, unstable market price and unsuitable market channel with the dominant of the traders. Final factors is the area and location of clam raising. Despite of these difficulties, 55.14% surveyed farms still want to expand their production, 25% of them will continue, and only 17.86% will stop or change to other activities. In order to promote the value added for clam raising farmers, cost control should be paid more attention, improvement of the farmers’ capacity is necessary, and market should be regarded. [less ▲]

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See detailMineralogy of fine particles in slurry from multispectral imaging
Leroy, Sophie ULg; Dislaire, Godefroid ULg; Barnabé, Pierre ULg et al

Conference (2014, September 02)

Quantitative mineralogy of fine particles in slurry from multispectral imaging Sophie Leroy, Godefroid Dislaire, Pierre Barnabé and Eric Pirard Mineral processing especially in its final stages relies ... [more ▼]

Quantitative mineralogy of fine particles in slurry from multispectral imaging Sophie Leroy, Godefroid Dislaire, Pierre Barnabé and Eric Pirard Mineral processing especially in its final stages relies heavily on the differential behavior of particles in pulps. In order to monitor hydrocyclones and flotation cells in almost real time, it is important to develop at line particle characterization providing information on particle distribution but also mineralogy. A sampling device has been elaborated based on a flow cell with variable wall spacing linked to a high pressure peristaltic pump. This setup allows for dispersion and dilution of the mineral slurry into the cell. Depending on the ore or gangue minerals to be controlled, particles can be imaged either in diffuse reflectance or in transmittance mode. A simple multispectral imaging module has been designed to acquire images at eight different wavelengths. The design is based on a series of dichroic filters thereby avoiding any moving part and enabling a very fast acquisition of multispectral images. Imaging artifacts due, among others, to specular reflectance from the glass window are minimized. Multispectral classification is used to outline particles appearing in the field of view and to qualify their main mineral component. In particular, areas reflecting a meaningful and discriminative spectrum are identified and compared to a multispectral database. The database is continuously enriched through testing of pure mineral particles under similar pulp conditions (dilution, grain size,…). Results of final classification are compared to the modal analysis obtained from polished blocks and conventional reflected light microscopy. The technology developed in this work sets the basis for at line monitoring of ore slurries with reasonably simple mineralogy. Extension of the spectral range is being considered for future developments. [less ▲]

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See detailFrom geometallurgy to ecometallurgy:Building mines for the future
Pirard, Eric ULg

Conference (2014, September 02)

geometallurgy will become the central pivot of a successful mining operation. Recently, Europe has awakened from a long period of lethargy in the raw materials sector. A series of important initiatives ... [more ▼]

geometallurgy will become the central pivot of a successful mining operation. Recently, Europe has awakened from a long period of lethargy in the raw materials sector. A series of important initiatives inspired by the European Innovation Partnership (EIP) have paved the way for more intense cooperation between industry, research centres and universities. Among these, the establishment of a Knowledge Innovation Community (KIC) in 2015 will definitely boost innovation and education in the sector. Interestingly, EIP addresses the whole value chain and considers mining, recycling and substitution as essential pillars of the raw materials policy. This vision strengthens the role of geometallurgy but also brings up the need for a close dialogue between mineralogists, metallurgists and product designers. Microelectronics and nanotechnologies are ubiquitous in our technologies and have greatly improved their functionality, but they have also made recycling and efficient recovery of metals a tough technical challenge. Our urban mines formed by the accumulation of end-of-life products should be scrutinized from now on using an ecometallurgical approach whereby important questions should be addressed such as: 1. Metal concentrations: Is the metal grade high enough to pay for recycling? Does the manufacturer help to maintain grades above a technological cut-off? 2. Metal speciation: Under which form (alloy, salt, organic compound,…) is the metal present? Is there a processing technology available to separate these species? 3. Metal paragenesis: What are the metal assemblages found in the product? Will it be feasible to separate those metals and at what costs? Are there penalty or contaminating elements associated? 4. Textural assemblage: How will the product behave during dismantling? Is it realistic to liberate a given component? What comminution strategy will be needed to achieve phase liberation? 5. Reserve estimation: What are the tonnages expected for this kind of product? Can selective collection be organised? 6. Homogeneity: What will the next generation of products look like? Should one expect strong differences in concentration, speciation, paragenesis, etc.? Will this kind of product be blended with others during collection? How will this impact on downstream recycling? Ecometallurgy, as introduced here, is essentially about establishing a dialogue with product designers and material scientists to make sure that, once unearthed, metals will remain easily and sustainably available for the future generations. Geologists and mineralogists, even though generally kept away from the synthetic materials, could greatly contribute to this progress by bringing their expertise in dealing with complex and variable orebodies of the future. [less ▲]

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See detailTechnical variability in the Gravettian with tanged tools: new results from Belgium
Touzé, Olivier; Flas, Damien ULg; Pesesse, Damien

Conference (2014, September 01)

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See detailA Multiphysics model of neotissue growth in a perfu sion bioreactor
Guyot, Yann ULg; Papantoniou, Ioannis; Schrooten, Jan et al

Conference (2014, September)

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See detailSelecting job candidates who have a propensity to exhibit change-oriented organizational citizenship behaviour.
Lothe, Benoit ULg; Hansez, Isabelle ULg

Conference (2014, September)

Purpose An abundant literature indicates that Organizational Citizenship Behaviours (OCBs) positively influence a number of important organizational outcomes. Furthermore, research is needed on the topic ... [more ▼]

Purpose An abundant literature indicates that Organizational Citizenship Behaviours (OCBs) positively influence a number of important organizational outcomes. Furthermore, research is needed on the topic of assessing and selecting applicants who have a propensity to exhibit OCB (Organ & al., 2010). Some of these behaviours are truly important to enable organization to adapt and “to make constructive changes in the work and task environment” (Choi, 2007, p.468). Examples include Voice, a challenging dimension of OCB (Dominguez & al., 2013), and Sportsmanship, that facilitate the change by reducing the diversion of resources in trivial matters (Organ & al., 2006). This exploratory study provides empirical evidence about using Situational Judgment Tests (SJTs) for identifying applicants who have a propensity to exhibit change oriented OCB. Method Two SJTs were developed to comply with OCBs assessment. The OCBs framework includes behaviours relating to organizational adaptation (sportsmanship) and change (voice). OCBs were concurrently collected using self-reported measurement scales. Data were collected from 220 white collars and 139 university students through an online survey. Results Significant correlations were found between the SJT scores and overall OCB ratings. More specifics findings provided substantial evidence for the concurrent validity of the SJTs to measure change-oriented sub-dimensions of OCBs. Conclusions Researches on techniques to predict OCBs are scarce and this study is the first to address the development and validation of a SJT for the assessment of affiliative and challenging dimensions of OCBs. [less ▲]

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See detailThe Belgian Reform of Mental Health: Changing the Face of Psychiatric Hospitals
Thunus, Sophie ULg

Conference (2014, September)

This paper focuses on the ongoing reform of psychiatric and mental health care delivery in Belgium. It starts by mentioning particularities of the system’s development, then it defines the reform’s ... [more ▼]

This paper focuses on the ongoing reform of psychiatric and mental health care delivery in Belgium. It starts by mentioning particularities of the system’s development, then it defines the reform’s objectives and policy instruments used to reach these objectives and, finally, it indicates specific issues and outcomes resulting from the implementing. [less ▲]

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See detailApplication of X-ray microtomography to investigate the effect of raw material properties on the kinetics of iron ores granulation
Evrard, Maxime ULg; Contreras, Rafael; Pirard, Eric ULg

Conference (2014, September)

In modern ironmaking, granulation is the first step of the sintering process. It is typically carried out in continuous drum granulators using water as a binder, and involves multiple components besides ... [more ▼]

In modern ironmaking, granulation is the first step of the sintering process. It is typically carried out in continuous drum granulators using water as a binder, and involves multiple components besides iron ores, such as return fines and other recycled materials (dusts, mill scale, sludges), solid fuel (coke breeze or anthracite) and fluxes (limestone, lime, olivine, dunite or dolomite) (Ball, 1973). As it is necessary to maintain a consistent quality of the granules (size distribution, porosity, strength, etc.) despite of the varying iron ore origins, the question arises as to how the properties of the iron ore particles (size and shape) influence the granulation process. The granulation process is partly influenced by the characteristic of the feed and partly by the action of cohesive force inside the drum granulator (Newitt et al. 1958). The objective of this paper is to study the effect of raw material properties on the kinetics of iron ore granulation considering in particular the mechanisms ruling wet granulation for two iron ores and to know the factors which determine the texture, shape, porosity and mechanical strength of the granules. [less ▲]

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See detailThe Double-Sarcophagus of Hierapytna (Creta). A Reassessment
Veymiers, Richard ULg

Conference (2014, September)

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See detailFormal Incident Reporting System: Putting Solidarity on Trial
Rossignol, Nicolas ULg; Claisse, Frédéric ULg

Conference (2014, September)

The practice of “incident reporting” is commonly recognized as an effective mean to reduce the vulnerability of “at risk” socio-technical systems (e.g. nuclear plants, large industrial facilities or ... [more ▼]

The practice of “incident reporting” is commonly recognized as an effective mean to reduce the vulnerability of “at risk” socio-technical systems (e.g. nuclear plants, large industrial facilities or hospitals), as it allow the concerned community to learn from past incidents. Indeed, it is assumed that collective resilience will be upgraded via the use of institutionalized Incident Reporting System (IRS), enabling the organization to improve the quality of the actions and reactions in case of deviation from normality, or to prevent such deviation. Yet, inductive analysis of what happens with those IRS in practice are not numerous. In this paper, we address this gap and display the results of semi-structured interviews conducted in a nuclear facility. During those interviews, participants were also requested to produce a mind map of the IRS they are concerned with. As a result, we show that safety is a matter of solidarities that are situated in specific contexts. To that regard, incident reporting is a practice of decomposition and recomposition of trusts and thus of solidarities. Reporting incidents consists in putting solidarity on trial, as the collective safety was threatened. We show that such open trial is often avoided because questioning solidarities is not always desirable in order to allow the group to continue functioning. Overall, we argue that informal reporting behaviors can also contribute to upgrade collective resilience without putting solidarities on trial. [less ▲]

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See detailImaging and understanding of iron ore granulation using X-ray mictrotomography
Evrard, Maxime ULg; Contreras, Rafael; Pirard, Eric ULg

Conference (2014, September)

Imaging and understanding of iron ore granulation using X-ray microtomography. Evrard M., Contreras R., Pirard E. Most iron ores cannot be directly fed into blast furnaces because their particle size ... [more ▼]

Imaging and understanding of iron ore granulation using X-ray microtomography. Evrard M., Contreras R., Pirard E. Most iron ores cannot be directly fed into blast furnaces because their particle size distribution will negatively impact the blast furnace permeability and hence the overall efficiency of the ore reduction process. The finest fraction (typ. < 6.3 mm) has to undergo a sintering process, wherein a mixture of iron ore, coke and flux (limestone, olivine,…) is heated, partially molten and transformed into pieces of sintered material with adequate size, porosity and strength characteristics to be fed into the blast furnace. The preparation of an adequate mixture involves a granulation process which is the subject of this study. Sintering and hence granulation of iron ores, is particularly important in Europe where iron ores show a downward trend in quality (finer particles, broader size range, lower grades with higher variability). In addition an increasing fraction of non-sintered material (return fines) is being added to the mix to optimize the resource efficiency while maintaining sinter quality. For most practitioners, microgranules (or micropellets) are considered as being composed of a nucleus (a particle in the range of 1 to 2 mm) surrounded by layers of the finest ore particles (typically the < 250 µm fraction). A series of experiments and 3D imaging tests have been performed in this study to better understand the granulation mechanisms. Microgranules are formed by mixing iron ore with water in a small rotating drum. Several parameters can be tuned during the granulation process: size and proportion of nucleating particles, size and proportion of fines, water addition, rotating speed, total duration,… Simple experiments using a single ore type (dominantly goethitic or hematitic) and water additions have been carried out systematically to better understand the kinetics of granulation. X-ray microtomography and subsequent 3D image analysis is used to identify and quantify the number of nuclei (when present), to measure the porosity and identify layering or cracks in the microgranule. Compared to previous studies on iron ore pellets (Farber et al. 2002; Shatokha et al. 2009; Shatokha et al. 2010), this work focuses on imaging prior to sintering. It also uses higher resolution micro-CT and definitely brings a better insight into granulation as compared to data from 2D imaging of polished blocks: less artefacts in apparent porosity due to sample preparation; good discrimination among components of the granule; clear identification of the nuclei; etc. This work is part of a larger European project (IMSIMI - Improved Sintering Mix) aiming at an optimal use of challenging input materials through carefully monitored preparation phases (mixing, granulation, etc.) and better understanding of their impact on the sintering process. Farber L., Tardos G., Michaels JN.,2002. Use of X-ray tomograzphy to study the porosity and morphology of granules. Powder Technology vol. 132, p 57-63. Shatokha V., Korobeynikov I., Maire E., Adrien J., 2009. Application of 3D X-ray tomography to investigation of structure of sinter mixture granules. Ironmaking and Steelmaking, vol. 36 (6), p 416-420. Shatokha V., Korobeynikov I., Maire E., Gremillard L., Adrien J.,2010. Iron ore sinter porosity characterisation with application of 3D X-ray tomography. Ironmaking and Steelmaking, vol. 37(5), p313-319. [less ▲]

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See detailRetrospective study of ventilation after major aortic surgery
KOCH, Jean-Noël ULg

Conference (2014, September)

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See detailTransfusion in aortic surgery
KOCH, Jean-Noël ULg

Conference (2014, September)

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See detailElicitor screening to protect winter wheat against Septoria tritici Blotch: preliminary results
Le Mire, Géraldine ULg; Deleu, Magali ULg; Ongena, Marc ULg et al

Conference (2014, September)

Elicitors are plant immunity-triggering compounds which are currently considered as one of the most promising tools in agriculture for the induction of plant resistance to various diseases (Mejía-Teniente ... [more ▼]

Elicitors are plant immunity-triggering compounds which are currently considered as one of the most promising tools in agriculture for the induction of plant resistance to various diseases (Mejía-Teniente et al., 2010). By contributing to both economic and environmental performances of agroecosystems, they can help reducing the use of chemical inputs. Although some elicitor products are already available on the market, it appears that a variable efficiency in the field, along with an uneasy integration in the current legislation and agricultural strategies, make these tools difficult to use (Walters, Ratsep, & Havis, 2013). Besides these limitations, few elicitor treatments have yet been efficiently and specifically designed to protect crop plants such as wheat, which is grown and consumed worldwide, against major diseases threatening both their yield and quality. There is a strong need to better understand the mechanisms of induced resistance in plants and develop elicitor use in agriculture. A phD research is currently led in Gembloux Agro Bio-Tech to develop a method based on eliciting agents, tested in greenhouse and field conditions, to protect winter wheat against major diseases, namely Septoria tritici, Fusarium graminearum and Fusarium culmorum. This project focuses on the screening of a large number of elicitors from different origins and structures. In 2014, we focused the first screening experiments on the protection of wheat against Septoria tritici Blotch (STB). Two winter wheat genotypes were tested: susceptible ‘Avatar’ and semi-resistant ‘Sy Epson’. Plants at 3-leaf stage were first sprayed till runoff with different concentrations of elicitors, and then inoculated 5 days later with a Septoria tritici spore suspension (106 spores mL-1) using a hand sprayer. Control plants were treated, prior to disease inoculation, with sterile water (negative control) or with BION® (ASM, Syngenta Europe; positive control). The disease severity and incidence were scored every 2 days for 28 days post-inoculation (d.p.i) by measuring the percentage of area covered with lesions and bearing pycnidia on the third leaf. The first results of these tests should enable a first discrimination of elicitors considering their dose-efficiency to reduce disease severity. After further screening of all the elicitors in hand, a determination of the elicitation pathways of the most efficient molecules tested will be undertaken. We intend to study the influence of various factors (i.e Temperature, relative humidity, plant development stage) on the elicitation potential and develop a formulation to be finally tested under field conditions. [less ▲]

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See detailMaster-narratives for science policy. The interplay of political discourses on Science in Wallonia.
Charlier, Nathan ULg

Conference (2014, September)

Both in Europe and in the United States, scientific research and science, technology and innovation (STI) policies have undergone profound changes for about thirty years. These transitions are often ... [more ▼]

Both in Europe and in the United States, scientific research and science, technology and innovation (STI) policies have undergone profound changes for about thirty years. These transitions are often framed along dichotomous lines : an ‘old regime’ characterized by strong public funding, independent academia and a linear conception of innovation has supposedly been replaced by a ‘new regime’ in which research and innovation are conceived in systemic terms, regarding their economic and societal relevance (Rip 2000). My proposal states that this conceptualization is of little use when it comes to studying the evolution of STI policies at the regional level. In this paper, I investigate how global master narratives like the “Knowledge-based Economy”, the “Grand societal Challenges”, “Science, the endless Frontier”, “Responsible Research and Innovation”, etc. are locally articulated, and thereby become grounded in regional STI policymaking, research, and innovation. These narratives, as explanatory resources and mobilizing resources, provide stakeholders with different visions; they are related to power relations between groups and individuals, to institutional settings and to policy trajectories. In my contribution, I study the four narratives in context; i.e. in different situated discourses of STI stakeholders. I consider multiple issues: who is telling what, to whom, why, when, where, and in which form. Instead of dichotomizing, investigating the evolutions of STI policies with a narrative framework provides an enriched description for complex local situations, towards a more political reading of the transitions. [less ▲]

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See detailImplications of microbial phenotypic heterogeneity in large-scale bioprocessing conditions
Delvigne, Frank ULg; Gorret, Nathalie; Molina-Jouve, Carole et al

Conference (2014, September)

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See detailLes objectifs de la formation des soignants en Education Thérapeutique du Patient : une proposition
Pétré, Benoît ULg; Guillaume, Michèle ULg; LEGRAND, Catherine et al

Conference (2014, September)

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See detailThe earliest seed plants from Gondwana: palaeogeographical and evolutionary implications based on Tournaisian (Mississippian) records from Argentina
Prestianni, C.; Rustán, J.J.; Balseiro, D. et al

Conference (2014, September)

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See detailAsteroseismology of evolved stars: from hot B subdwarfs to white dwarfs
Van Grootel, Valérie ULg; Fontaine, G.; Charpinet, S. et al

Conference (2014, September)

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See detailLe test conflictuel - un colosse aux pieds d'argile?
Wautelet, Patrick ULg

Conference (2014, September)

Cette présentation a servi de support à une communication tendant à faire le point sur l'article 27 du Code de droit international privé. La communication avait comme objectif de démontrer les difficultés ... [more ▼]

Cette présentation a servi de support à une communication tendant à faire le point sur l'article 27 du Code de droit international privé. La communication avait comme objectif de démontrer les difficultés du régime actuel d'accueil en Belgique des actes étrangers en Belgique et à formuler des pistes de solution pour améliorer ce régime. [less ▲]

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See detailβ 5 tubulin and 15-protofilament microtubules appeared in supporting cells of the Corti’s organ during development in rodents
Renauld, Justine ULg; Thelen, Nicolas ULg; Johnen, Nicolas et al

Conference (2014, August 31)

A feature of the organ of Corti’s supporting cells is the presence of an abundant cytoskeleton which is mainly composed of microtubules. These supporting cells have also been shown to contain a minor ... [more ▼]

A feature of the organ of Corti’s supporting cells is the presence of an abundant cytoskeleton which is mainly composed of microtubules. These supporting cells have also been shown to contain a minor mammalian tubulin, the β5-tubulin [1], recently related as a biomarker for cancer outcome [2] and cell proliferation [3]. It was shown that a β-tubulin isoform can specified the microtubule architecture, such as the expression of the Moth β2 in the Drosophila testes imposed the 16 protofilaments (16pf) structure on the corresponding subset of Drosophila microtubules, which normally contain 13pf [4]. Moreover, supporting cell microtubules are formed by 15pf instead of the canonical 13, a unique fact among vertebrates [5]. Such a protofilament configuration has been observed in C. elegans’ neurons which are responsible for the mechanosensory sense of touch [6]. It was also shown that these 15pf microtubules were essential to the proper functioning of these mechanosensory neurons [6]. To determine the role of this particular tubulin in the auditory organ and its possible involvement in the formation of the unusual 15pf microtubules of supporting cells, we studied the spatiotemporal localization of β5-tubulin during development in rats from embryonic day 18 until P25 (25th postnatal day). We also analyzed the localization of β5-tubulin mRNA expression in the Corti’s organ. Then we examined the fine structure of microtubules at the electron microscope level. For these experiments, we used an early postnatal stage and a late postnatal stage. Our results showed that β5-tubulin, contrary to other β-tubulins, had a unique distribution in the cochlea. This β-tubulin appeared at a postnatal stage, before the opening of the Corti’s tunnel and being restricted to supporting cells, especially in pillar and Deiters cells,. The same localization of β5-tubulin mRNA was observed by in Situ Hybridization. Electron microscopy indicated further that Pillar and Deiters cells were composed by 15-protofilament microtubules at the late postnatal stage (P25). In conclusion, all these data strongly suggest that there is a relationship between the presence of β5-tubulin and 15-protofilament microtubules in the supporting cells of the auditory organ. Further studies are now needed to elucidate their role. [less ▲]

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See detailProblématique foncière chez les exploitants agricoles de la Province de Kirundo au nord du Burundi
Minani, Bonaventure; Rurema, Déo-Guide; Burny, Philippe ULg et al

Conference (2014, August 30)

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See detailAspects économiques de la filière du vermicelle de tolomane au Vietnam
Le Thi Long, Vy; Vu Dinh, Ton; Lebailly, Philippe ULg et al

Conference (2014, August 30)

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See detailThe effects of a Global Agricultural Policy on the smallholder farmers in ending hunger
Paveliuc-Olariu, Codrin; Burny, Philippe ULg

Conference (2014, August 30)

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See detailAmélioration des moyens d'existence durables. Une voie pour la durabilité des exploitations agricoles familiales de coton au Bénin
Assogba, Claude Gervais; Tossou, C. R.; Lebailly, Philippe ULg et al

Conference (2014, August 30)

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See detailL'agriculture de subsistance et de semi-subsistance en Roumanie
Dona, Ion; Burny, Philippe ULg

Conference (2014, August 30)

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See detailAccelerating Random Forests in Scikit-Learn
Louppe, Gilles ULg

Conference (2014, August 29)

Random Forests are without contest one of the most robust, accurate and versatile tools for solving machine learning tasks. Implementing this algorithm properly and efficiently remains however a ... [more ▼]

Random Forests are without contest one of the most robust, accurate and versatile tools for solving machine learning tasks. Implementing this algorithm properly and efficiently remains however a challenging task involving issues that are easily overlooked if not considered with care. In this talk, we present the Random Forests implementation developed within the Scikit-Learn machine learning library. In particular, we describe the iterative team efforts that led us to gradually improve our codebase and eventually make Scikit-Learn's Random Forests one of the most efficient implementations in the scientific ecosystem, across all libraries and programming languages. Algorithmic and technical optimizations that have made this possible include: - An efficient formulation of the decision tree algorithm, tailored for Random Forests; - Cythonization of the tree induction algorithm; - CPU cache optimizations, through low-level organization of data into contiguous memory blocks; - Efficient multi-threading through GIL-free routines; - A dedicated sorting procedure, taking into account the properties of data; - Shared pre-computations whenever critical. Overall, we believe that lessons learned from this case study extend to a broad range of scientific applications and may be of interest to anybody doing data analysis in Python. [less ▲]

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See detailComputational homogenization of cellular materials with propagation of instabilities through the scales
Nguyen, Van Dung ULg; Noels, Ludovic ULg

Conference (2014, August 29)

The aim of this work is to develop an efficient multi–scale finite element framework to capture the buckling instabilities in cellular materials. As a classical multi–scale computational homogenization ... [more ▼]

The aim of this work is to develop an efficient multi–scale finite element framework to capture the buckling instabilities in cellular materials. As a classical multi–scale computational homogenization scheme looses accuracy with the apparition of the macroscopic localizations resulting from the micro–buckling, the second–order multi–scale computational homogenization scheme1 is considered. This second–order computational framework is herein enhanced with the following novelties so that it can be used for cellular materials. First, at the microscopic scale, the periodic boundary condition is used because of its efficiency. As the meshes generated from cellular materials exhibit a large void part on the boundaries and are not conforming in general, the classical enforcement based on the matching nodes cannot be applied. A new method based on the polynomial interpolation2 without the requirement of the matching mesh condition on opposite boundaries of the representative volume element (RVE) is developed. Next, in order to solve the underlying macroscopic Mindlin strain gradient continuum of this second–order scheme by the displacement–based finite element framework, the treatment of high order terms is based on the discontinuous Galerkin (DG) method to weakly impose the C1-continuity3. Finally, as the instability phenomena are considered at both scales of the cellular materials, the path following technique is adopted to solve both the macroscopic and microscopic problems4. The micro–buckling leading to the macroscopic localization and the size effect phenomena can be captured within the proposed framework. In particular it is shown that results are not dependent on the mesh size at the macroscopic scale during the softening response, and that they agree well with the direct numerical simulations. [less ▲]

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See detailInnovative lactation stage specific prediction of CH4 from milk MIR spectra
Vanlierde, Amélie; Vanrobays, Marie-Laure ULg; Dehareng, Frédéric et al

Conference (2014, August 28)

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See detailPrediction of meso-scale mechanical properties of poly-silicon materials
Lucas, Vincent ULg; Wu, Ling ULg; Arnst, Maarten ULg et al

Conference (2014, August 27)

The miniature sizes of micro–electro–mechanical systems (MEMS) as well as the nature of their manufacturing processes, such as etching, material layer deposition, or embossing, are responsible for the ... [more ▼]

The miniature sizes of micro–electro–mechanical systems (MEMS) as well as the nature of their manufacturing processes, such as etching, material layer deposition, or embossing, are responsible for the existence of a scatter in the final dimensions, material properties ... of manufactured micro–sensors. This scatter is potentially threatening the behavior and reliability of samples from a batch fabrication process, motivating the development of non-deterministic computational approaches to predict the MEMS properties. In this work we extract the meso-scale properties of the poly-silicon material under the form of a probabilistic distribution. To this end, Statistical Volume Elements (SVE) of the micro-structure are generated under the form of a Voronoï tessellation with a random orientation for each silicon grain. Hence, a Monte-Carlo procedure combined with a homogenization technique allows a distribution of the material tensor at the meso-scale to be estimated. As the finite element method is used to discretize the SVE and to solve the micro-scale boundary value problem, the homogenization technique used to extract the material tensor relies on the computational homogenization theory. In a future work, we will investigate, in the context of MEMS vibrometers, the propagation to the macro–scale of the meso-scale distribution of the homogenized elasticity tensor, with the final aim of predicting the uncertainty on their resonance frequencies. [less ▲]

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See detailEarly Silurian cryptospores from the subsurface of Saudi Arabia
Wellman, C.; Breuer, P.; Miller, M. et al

Conference (2014, August 26)

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See detailUsing milk spectral data for large-scale phenotypes linked to mitigation and efficiency
Soyeurt, Hélène ULg; Vanlierde, Amélie; Vanrobays, Marie-Laure ULg et al

Conference (2014, August 26)

Even if producing milk efficiently has always been a major concern for producers, the direct environmental impact of their cows is becoming a novel one. Traits linked to this issue were identified as ... [more ▼]

Even if producing milk efficiently has always been a major concern for producers, the direct environmental impact of their cows is becoming a novel one. Traits linked to this issue were identified as methane emission (CH4), dry matter intake (DMI) and feed efficiency (FE); however they are available on a small scale. Researches showed that CH4 could be predicted from milk mid-infrared (MIR) spectra, allowing large-scale recording at low cost. The main objective of this study was to show, using a modelling approach, that DMI and FE could be derived from milk MIR spectra. For that, knowledge of body weight (BW) is required; however it was unknown in this study. Derived procedure was based on milk yield and composition, MIR CH4, and modelled standard animal requirements, allowing the prediction of expected BW. An external validation was conducted based on 91 actual records. 95% confidence limit for the difference ranged between -0.66 and 18.84 kg for BW, from -0.02 to 0.26 kg/day for DMI, and from -0.02 to 0.002 kg of fat corrected milk/kg DM for FE. Root mean square errors were 39.66 kg, 0.56 kg/d, and 0.03 kg/DM for the 3 studied traits. P-value for the t-test was not significant for BW and DMI. This suggests the possibility to obtain expected BW and therefore DMI from MIR spectra. Single trait animal test-day models used 1,291,850 records to assess the variability of studied traits. Significant variations were observed for the lactation stage, parity, genetics, and age. These findings were in agreement with the literature except for early lactation. This suggests in conclusion that the MIR information gave similar results for DMI and CH4 for the major part of lactation. The use of this novel method to predict expected BW offers new possibilities interesting for the development of genomic and genetic tools. [less ▲]

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See detailIncreasing the efficiency of Organic Rankine Cycle Technology by means of Multivariable Predictive Control
Hernandez Naranjo, Jairo Andrés ULg; Desideri, Adriano ULg; Ionescu, Clara et al

Conference (2014, August 25)

The Organic Rankine Cycle (ORC) technology has become very popular, as it is extremely suitable for waste heat recovery from low-grade heat sources. As the ORC system is a strongly coupled nonlinear ... [more ▼]

The Organic Rankine Cycle (ORC) technology has become very popular, as it is extremely suitable for waste heat recovery from low-grade heat sources. As the ORC system is a strongly coupled nonlinear multiple-input multiple-output (MIMO) process, conventional control strategies (e.g. PID) may not achieve satisfactory results. In this contribution our focus is on the accurate regulation of the superheating, in order to increase the e fficiency of the cycle and to avoid the formation of liquid droplets that could damage the expander. To this end, a multivariable Model Predictive Control (MPC) strategy is proposed, its performance is compared to the one of PI controllers for the case of variable waste-heat source profi les. [less ▲]

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See detailmodelling heat and mass transfer during convective drying of a building material
Kahlerras, Loubna ULg

Conference (2014, August 24)

The purpose of this study is to characterize experimentally the behaviour of a cement mortar during its convective drying. The work presented here focuses on mortars with water-to cement ratios (w/C) of 0 ... [more ▼]

The purpose of this study is to characterize experimentally the behaviour of a cement mortar during its convective drying. The work presented here focuses on mortars with water-to cement ratios (w/C) of 0, 5. The drying tests are realized in a convective dryer designed for the drying of small samples (0 - 8g). Experiences are realized with different conditions of drying air temperature (60, 90 and 130 °C) and velocity (2, 3 and 5 m/s) the results show the influence of temperature and velocity on drying curve. Mathematical models have been used for the description of drying curves. The exponential mathematical model seems the most adequate to describe the drying curves of cement mortars, with correlation coefficients changing with the air temperature and velocity and close to unity. The convective mass and heat transfer coefficients are determined from the experimental data. The results showed that both mass and heat transfer coefficients were affected by the air temperature and velocity. The convective mass transfer coefficient changed from 0.0232m/s at V=2m/s to 0.045m/s at V=5m/s, and from 0.055 m/s at 60°c to 0.023 at 130°c. Heat transfer coefficient changed from 14.767 w/m2°c at V=2m/s to 28.64 w/m2°c at V=5m/s and from 7.71 at 60° c to 14.77 at 130°c The temperature dependency of the two coefficients was expressed using an Arrhenius-type equation and related parameters were deduced [less ▲]

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See detailExperimental study of the drying kinetic of mortar
Kahlerras, Loubna ULg

Conference (2014, August 24)

This work reports the results of an experimental study concerning on one hand the influence of water-to cement ratios (W/C), and the role of aggregates on the other hand on the drying kinetics of cement ... [more ▼]

This work reports the results of an experimental study concerning on one hand the influence of water-to cement ratios (W/C), and the role of aggregates on the other hand on the drying kinetics of cement pastes during thermal drying. Three types of cement pastes were realized and studied; cement pastes with ratios W/C 0.4, W/C 0.5 and mortar with ratio W/C 0.5. These tries present the advantage to reproduce the natural conditions met in the problems of interaction atmosphere and material. Cylindrical samples of cement of size (17 X 13) mm are dried in a convective dryer. The sample is continuously weighed during the drying test and its mass is recorded every 60 s, in the purpose to obtain the drying curves. The results show that the increase of the W/C ratio leads to an increase of the drying rate due to the increase of the initial porosity. The effect of the introduction of aggregates is observable by the comparison of the drying curve obtained for the mortar and the cement pastes. The results show a decrease of the drying kinetics with mortars. The results also show that the air drying temperature has a large impact on the drying process, increasing the temperature leading to significant drying time reduction. The Effective diffusion coefficient is calculated by comparison between the experimental results and the analytical solution of Fick’s equation written for a finite medium. [less ▲]

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See detailComparison of robust detection techniques for local outliers in multivariate spatial data
Ernst, Marie ULg; Haesbroeck, Gentiane ULg

Conference (2014, August 22)

Spatial data are characterized by statistical units, with known geographical positions, on which non spatial attributes are measured. Spatial data may contain two types of atypical observations: global ... [more ▼]

Spatial data are characterized by statistical units, with known geographical positions, on which non spatial attributes are measured. Spatial data may contain two types of atypical observations: global and/or local outliers. The attribute values of a global outlier are outlying with respect to the values taken by the majority of the data points while the attribute values of a local outlier are extreme when compared to those of its neighbors. Usual outlier detection techniques may be used to find global outliers as the geographical positions of the data is not taken into account in this specific search. The detection of local outliers is more complex, especially when there are more than one non spatial attributes. This talk focuses on local detection with two main objectives. First, we will shortly review some of the local detection techniques that seem to perform well in practice. Among these, one can find robust ``Mahalanobis-type'' detection techniques and a wheighted PCA approach. We suggest an adaptation to one of these to further develop its local characteristic. Then, examples and simulations, based on linear model of co-regionalisation with Matern models, are reported and discussed in order to compare in an objective way the different detection techniques. [less ▲]

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See detailModeling of the cyclic lipodepsipeptide Pseudodesmin A self-assembly through molecular dynamic simulations
Crowet, Jean-Marc ULg; Sinnaeve, Davy; Fehér, Krisztina et al

Conference (2014, August 20)

The self-assembly of short peptides into supramolecular structures represents an active field of research with potential applications, ranging from material sciences to medicine. Pseudodesmine A is a ... [more ▼]

The self-assembly of short peptides into supramolecular structures represents an active field of research with potential applications, ranging from material sciences to medicine. Pseudodesmine A is a cyclic lipodepsipeptide of nine residues which presents a moderate antibacterial activity and whose structure has been resolved by X-ray and NMR. In acetonitrile, Pseudodesmine A is monomeric while in chloroform, it has the same structure but assembles in a supramolecular complex. This structure could associate with membranes and be responsible for the biological activity of the peptide. Comparison of NMR data in the two solvents has given indications on the intermolecular contacts that arise in chloroform and a model for the self-association was proposed. To study in more details this assembly, molecular dynamics simulations have been carried on. The resultswere compared with detailed information given by NMR, regarding the dimensions of the assembly and the orientation of the individual peptide building blocks inside the supramolecular assembly. In acetonitrile, the simulations show that the peptide has transient interactions while in chloroform, interactions between monomers are always observed. In agreement with NMR, these interactions arise mainly between the backbone protons of the LEU1 and the GLN2, the GLN2 sidechain and the loop located on the opposite end of the monomer structure. From 10 simulations of dimerization, hydrogen bonds were followed and specific interaction patterns were identified regarding the hydrogen bonds formed. Peptide interactions are mainly described by 13 interaction patterns characterized by 2 to 4 hydrogen bonds. In dimers, the peptides can have a linear, a perpendicular or a side by side configuration. From the linear dimer, it is possible to reconstruct filaments and, by combining a linear and a lateral dimer, it is possible to build fibrils with multifilaments, as found in the NMR-derived model. Two self-consistent supramolecular models can be built from dimers and they present a very good correlation with NMR data regarding the supramolecular organization. Besides, the perpendicular dimer can gives peptide rings that can also explain the potential ability of this peptide to form ion pores in membranes. [less ▲]

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See detailThe taste bud and the form. Ethnography of sensory labs
Vangeebergen, Thomas ULg

Conference (2014, August 20)

Sensory analyses present an opportunity to challenge classical dualism, especially when it is about taste. During long-term fieldworks, I accompanied several types of sensory expert panels, which had the ... [more ▼]

Sensory analyses present an opportunity to challenge classical dualism, especially when it is about taste. During long-term fieldworks, I accompanied several types of sensory expert panels, which had the mission to discriminate different sorts of products and define their respective sensory profile. I was interested to observe the period of training to understand how those people had acquired their expertise, and how their attention toward their own sensations were entangled to scientific infrastructures. Using sensory ethnographic methods, I assisted to the emergence of a particular world, in which the classical categories for science practices and taste perception were completely blurred. To establish a common truth, through sturdy and stable categories, appears to be compatible with personal moods and dispositions, singular and hedonic judgments, sociocultural grounded sensorium, contingent elements, and indeterminate parameters. Resorting to standard tests, educated and coached judges, statistical treatments, specific vocabulary, comparisons to physic-chemical analysis and various other apparatuses, these labs tempt to define and assess some food products. The goal of those examinations could be multiple: to outline consumers¿ feelings and choices, to check the quality of production, to search new applications, or to improve a current array. What interested me is the quest to an object practically exploitable in an industrial and commercial context, avoiding all kind of idiosyncratic experiences. In this presentation, I would tempt an analysis of those particular tests, focusing on the double bind of testing products and testing consumers, and searching to assess the causes of organoleptic variability. [less ▲]

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See detailMetropolitan governance rescaling in Belgium, France and United Kingdom. Studying boundaries of urban governments through the application of an analytical framework for institutional changes.
Breuer, Christophe ULg

Conference (2014, August 20)

Second tier European cities (small metropolis or regional cities) are subject to permanent reconfigurations of their governance. These changes are the response to both external and internal ... [more ▼]

Second tier European cities (small metropolis or regional cities) are subject to permanent reconfigurations of their governance. These changes are the response to both external and internal transformations. On the one side, they are facing external pressures as increased competition between cities, European integration, legislative evolution or paradigm switch. On the other side, cities are dealing with internal problems: urban sprawl, socio-spatial segregation, actors’ fragmentation, financial issues, etc. These tensions renew themselves and take various shapes. They are wondering cities governance and ways to manage them. To cope with new challenges in a new context, cities are trying to reconfigure their collective action in a new spatiality and with new coordination modes. In this context, inherited institutional boundaries – that could be seen as obsolete or inadequate in a changing World – are particularly under pressure. Cities governments and their spatial limits are a central issue for researchers, politicians and urban actors, and a major component of the urban or metropolitan governance. Although second-tier cities are an essential part of the “polycentric system of European cities”, attention has essentially been focused on large metropolis and capital cities, where the problem occurred earlier. Furthermore, there is an extended literature on institutional change and the “rescaling”, but research mainly focused on the response of cities to economic changes; few analysis offer a good comprehension of particular trajectories and evolution of cities limits which are highly embedded in local context. These shortcomings make the reading of contemporary mutations particularly complex for local actors. Our paper presents our research on the development and the validation of an analytical framework to interpret changes in cities’ governments boundaries. We improved and used a framework based on institutional change and social change, which combined both institutional design theories and self-organization theories. The analytical framework had been tested on the last decades government limits changes of regional cities and small metropolis in France (Saint-Étienne, Metz), United Kingdom (Sheffield) and Belgium (Liège, Brussels). The research was carried on with historical and geographical data collected during research stays in each of these cities: historical evolution of cities limits, legislation’ development, urbanization trajectory, etc. The research leads to some conclusions. Firstly, it is possible to develop a generic analytical framework to identify and interpret mutations of city government limits. This framework helps to make a systematic identification of actors’ dynamics, internal or external pressure and spatial changes, and go ahead apparent dichotomy between quick adjustment and high stability of some governance configuration. Secondly, the analytical model shows there is a common scheme of city limits evolution, which is driven among others things by European common dynamics (specifically economic and political dynamic). Thirdly, despite similarities in cities government boundaries changes, the analytical model demonstrates the importance of local contexts to understand individual evolutions and the specific trajectory of a city’ limits. [less ▲]

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See detailCommémorations et souvenirs d'août 1914 à Liège
Lanneau, Catherine ULg

Conference (2014, August 20)

Comment, au fil des décennies, a-t-on célébré à Liège et dans sa région, le souvenir des événements d’août 1914, à commencer par la bataille de Liège et la résistance des forts ? Comment les autorités et ... [more ▼]

Comment, au fil des décennies, a-t-on célébré à Liège et dans sa région, le souvenir des événements d’août 1914, à commencer par la bataille de Liège et la résistance des forts ? Comment les autorités et les Liégeois eux-mêmes ont-ils contribué à construire la mémoire de ce mois tragique ? Comment, notamment, la presse locale a-t-elle rendu compte de ces manifestations ? Cette communication analyse l’évolution du contexte commémoratif liégeois de 1924 à 2004. Dans l’entre-deux-guerres, le souvenir d’août 1914 est extrêmement vif : les rescapés sont encore très nombreux, la germanophobie s'exprime avec force et le contexte international interfère puissamment sur la commémoration. Après la Seconde Guerre, un triple enjeu s’impose : gérer la concurrence ou la confusion de la mémoire et du souvenir entre les deux conflits mondiaux, entretenir la flamme de ce souvenir alors que le temps s’écoule et que les survivants se raréfient, et enfin appréhender un contexte international, lié notamment à la guerre froide, dans lequel l’Allemagne (de l’Ouest) est avant tout un partenaire politique et économique. En outre, dès les années 1970 mais surtout 1980, l'idée d'un tourisme mémoriel se fraie un chemin dans une région en pleine reconversion économique. [less ▲]

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See detailA multifractal analysis of air temperature signals based on the wavelet leaders method
Deliège, Adrien ULg; Nicolay, Samuel ULg

Conference (2014, August 20)

We present the wavelet leaders method (introduced by S. Jaffard) as a tool to study the Hölder regularity of signals, which is closely related to some functional spaces. We use the associated multifractal ... [more ▼]

We present the wavelet leaders method (introduced by S. Jaffard) as a tool to study the Hölder regularity of signals, which is closely related to some functional spaces. We use the associated multifractal formalism to show that surface air temperature signals are monofractal, i.e. these are regularly irregular. Then we use this result to establish a climate classification of weather stations in Europe which matches the Köppen-Geiger climate classification. This result could give rise to new criteria to determine the effectiveness of current climatic models. [less ▲]

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See detailLe poids d'août 1914 dans les relations belgo-allemandes (1914-1964)
Brüll, Christoph ULg

Conference (2014, August 20)

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See detailMitigation strategies versus Adaptation strategies
Gengler, Nicolas ULg

Conference (2014, August 17)

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See detailMapping key pollutants in the English Channel region: the Channel Catchments Cluster (3C) cross-border project
Richir, Jonathan ULg; Pini, Jennifer; Watson, Gordon

Conference (2014, August 16)

The EU Water Framework Directive was a response to concerns about the previous disparate ways in which water quality was managed under Member State law and early European Directives. Within this context ... [more ▼]

The EU Water Framework Directive was a response to concerns about the previous disparate ways in which water quality was managed under Member State law and early European Directives. Within this context, the Interreg IVA France (Channel) England Region established the ‘sustainable environmental development of this common space’ as one of its priorities to integrate areas that face common problems. The wide variety of cooperative cross-border projects have brought together UK and French scientists and environmental managers to develop practical environmental management tools for the region (3Cs cluster). Using the Solent in the UK as a case study, maps of key pollutants (e.g. metals such as Zn and Cu) will be produced to assess their spatial diversity within the sediment. The incorporation of historical datasets will also provide a temporal component. The inclusion of bioavailable fractions (using sequential extraction methods) will enable the pollutants to be linked to the tissue concentrations of key benthic species such as the polychaete Nereis virens and possible impacts. Not only will this information provide a detailed account of the water quality of key areas of the English Channel, but it will also highlight the gaps in the data and sampling regimes that are necessary to achieve good environmental status for the future, thus ensuring more effective European environmental policy regarding the long-term protection and conservation of aquatic ecosystems. [less ▲]

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See detailMetropolitan governance of European medium-size cities. Linking cities trajectories and mode of governance.
Breuer, Christophe ULg

Conference (2014, August 16)

In the past few years, an increased attention has been paid to the effect of governance on regional development and trajectories. It is commonly argued by scholars and practitioners that governance is a ... [more ▼]

In the past few years, an increased attention has been paid to the effect of governance on regional development and trajectories. It is commonly argued by scholars and practitioners that governance is a key factor of regional competitiveness and differentiation. In this context, some institutions as the Organization for Economic Co-operation and Development (OECD), the United Nations (UN) or the European Commission (EC) claim that a better governance (or actually “good governance”) leads to better places to live, enhanced competitiveness and less segregation. In the same time, research, public efforts and investments has been focused on metropolitan regions as lever for economic development. If there is a consensus on the role of governance on metropolitan and urban development, researches mainly focused on cases analysis and bigger metropolis regions. Few empirical studies tried to link metropolitan governance and metropolitan trajectories in European Union, particularly for medium-size cities and metropolitan area (100.000 - 1.000.000 inhabitants), which represents a significant proportion of the European population and economy. Nowadays, some exploratory researches based on the Urban Audit (European Commission) and complementary surveys give us additional information on governance of such cities. In our research, we aimed to explore the link between metropolitan governance of medium-sized cities and their trajectories. We used latest data from the European Commission (Urban Audit, Perception survey, Regional Statistic Database - Eurostat) and additional sources for socio-economic, environmental and governance indicators (especially metropolitan governance typology). We integrated in our work previous researches on this topic. Our exploratory research pointed out pattern and similarities in European medium-sized cities governance and trajectories. Despite some difficulties to distinguish governance effects to other determinants of well-being and competitiveness, it opens questions on “governance matters” leitmotiv, public policy adequacy and innovation capacity in European cities. [less ▲]

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See detailNiche conservatism and conservation biology of Lepilemur in northwest Madagascar
Wilmet, Leslie ULg; Vermeulen, Cédric ULg; Schwitzer, Christoph et al

Conference (2014, August 14)

The main goals of our study is to verify the existence and extent of niche conservatism in three closely related species within the genus Lepilemur, and to draw conclusions on the applicability of ... [more ▼]

The main goals of our study is to verify the existence and extent of niche conservatism in three closely related species within the genus Lepilemur, and to draw conclusions on the applicability of conservation protocols to a broader array of Lepilemur species. The genus is an exemplary of the mammalian fauna of Madagascar which high biological diversity is under increasingly severe threat from anthropogenic degradation of its forest habitats. This study focuses particularly on three poorly-known Lepilemur taxa: L. sahamalazensis, L. dorsalis and L. mittermeieri, uplisted into one of the threatened categories of the IUCN Red List.The genus is particularly negatively affected by deforestation and habitat fragmentation and all have a small distribution range, fairly small total populations. Their pattern of distribution appears to have been established through vicariant speciation, probably driven by changes in the configuration of the hydrographic system. Such a pattern permits to expect a high level of niche conservatism. We present here our preliminary results of an exploratory mission on 1) evaluation of Lepilemur abundance in forest patches on the Ampasindava Peninsula, the Sahamalaza Peninsula and the Manongarivo Special Reserve 2) sleeping sites characteristics of the three studied species. [less ▲]

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See detailVirus indexing and sanitation of international banana collection: insights from a 5-year collaborative effort
De Clerck, Caroline ULg; Parmenter, Kathleen; Vandenhouwe, Ines et al

Conference (2014, August 14)

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See detailBarley (Hordeum distichon L.) roots produce volatile aldehydes via the lipoxygenase/hydroperoxide lyase pathway with a strong age-dependent pattern
Delory, Benjamin ULg; Delaplace, Pierre ULg; du Jardin, Patrick ULg et al

Conference (2014, August 13)

In chemical ecology, the roles played by root-emitted volatile organic compounds (VOCs) in biotic interactions and the quantitative analysis of such chemicals in root tissues remain poorly documented. In ... [more ▼]

In chemical ecology, the roles played by root-emitted volatile organic compounds (VOCs) in biotic interactions and the quantitative analysis of such chemicals in root tissues remain poorly documented. In this context, this study aims at using a fully automated gas chromatography – mass spectrometry methodology allowing both identification and accurate quantification of VOCs produced by roots of a monocotyledonous plant species at five selected developmental stages from germination to the end of tillering. Results show that barley roots mainly produce four volatile aldehydes, namely hexanal, (E)-hex-2-enal, (E)-non-2-enal and (E,Z)-nona-2,6-dienal. These molecules are well-known linoleic and linolenic acid derivatives produced via the lipoxygenase/hydroperoxide lyase pathway of higher plants. Our findings contrast with analyses documented on aboveground barley tissues that mainly emit C6 aldehydes, alcohols and their corresponding esters. Multivariate statistical analyses performed on individual VOC concentrations indicate quantitative changes in the volatile profile produced by barley roots according to plant age. Barley roots produced higher total and individual VOC concentrations when young seminal roots emerged from the coleorhizae compared to older phenological stages. Moreover, results also show that the C6/C9 volatile aldehyde ratio was the lowest at the end of tillering while the maximum mean value of this ratio was reached in seven day-old barley roots. [less ▲]

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See detailDesign of biocompatible and responsive hydrogels and nanogels made from poly(2-oxazoline)s
Legros, Camille ULg; Gillet, Marie-Claire ULg; tam, Michael et al

Conference (2014, August 12)

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See detailRobustness and efficiency of multivariate coefficients of variation
Aerts, Stéphanie ULg; Haesbroeck, Gentiane ULg; Ruwet, Christel ULg

Conference (2014, August 12)

The coefficient of variation is a well-known measure used in many fields to compare the variability of a variable in several populations. However, when the dimension is greater than one, comparing the ... [more ▼]

The coefficient of variation is a well-known measure used in many fields to compare the variability of a variable in several populations. However, when the dimension is greater than one, comparing the variability only marginally may lead to controversial results. Several multivariate extensions of the univariate coefficient of variation have been introduced in the literature. In practice, these coefficients can be estimated by using any pair of location and covariance estimators. However, as soon as the classical mean and covariance matrix are under consideration, the influence functions are unbounded, while the use of any robust estimators yields bounded influence functions. While useful in their own right, the influence functions of the multivariate coefficients of variation are further exploited in this talk to derive a general expression for the corresponding asymptotic variances under elliptical symmetry. Then, focusing on two of the considered multivariate coefficients, a diagnostic tool based on their influence functions is derived and compared, on a real-life dataset, with the usual distance-plot. [less ▲]

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See detailRestoration of threatened metallophyte populations in Katanga (D.R. Congo): lessons learnt.
Le Stradic, Soizig ULg; Seleck, Maxime ULg; Le Brun, Julie et al

Conference (2014, August 05)

One of the current major challenges consists in integrating economic activities with environmental integrity and social concerns. One of the world’s largest concentrations of copper and cobalt deposits is ... [more ▼]

One of the current major challenges consists in integrating economic activities with environmental integrity and social concerns. One of the world’s largest concentrations of copper and cobalt deposits is located in Katanga (Democratic Republic of Congo) and represents an important source of income for the country. Unique communities and several endemic species are hosted on copper outcrops and are threatened by the extension of mining activities in the area. In theory, translocation or transplantation of structuring and/or endemic species is a suitable substitute to spontaneous succession and a good mean to rescue and conserve the more threatened species. Here we present briefly the global framework developed with a mining company in order to conserve and restore the biodiversity of Cu-Co communities, including, among others, translocation and transplantation of highly threatened species. We recorded low survival of translocated individuals. An alternative was then to produce seedlings of endemic and/or structuring species under nursery conditions for their later transplantation in degraded areas or for conservation purposes. However, the diversity of plant forms and life-forms found in such tropical area limited the production of many species. We highlighted that poor understanding of many of these tropical plants often hampered their regeneration and their use in restoration program. As already noticed, transplantation results are not always reported, especially in case of failure, while such results appear as even more important than successes and have to be presented. [less ▲]

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See detailFeeding ecology of harpacticoid copepod species: Insights from stable isotopes analysis and fatty acid profiling
Mascart, Thibaud ULg; De Troch, Marleen; Remy, François ULg et al

Conference (2014, August 04)

Understanding how biodiversity influence ecosystem functioning is a major research question in current ecology research. Trophic diversity within communities strongly affects ecosystem functioning through ... [more ▼]

Understanding how biodiversity influence ecosystem functioning is a major research question in current ecology research. Trophic diversity within communities strongly affects ecosystem functioning through trophic interactions between species. Various studies tackled ecosystem functioning via interactions between trophic guilds such as bottom-up and top-down control. However, few studies focussed on interspecific variability in the feeding ecology of organisms with overlapping trophic niche. Here, we in a North-Western Corsican Posidonia oceanica seagrass meadow and its variability over one year. The extensive P. oceanica meadows are occasionally interrupted by bare sand patches which serve as deposition and accumulation area for detritus, mainly derived from senescent macrophytes. These macrophytodetritus accumulation harbour a diverse community of Harpacticoida (Crustacea, Copepoda). The most abundant harpacticoids and their potential food sources (i.e. macrophytodetritus, epiphytic biofilm, macroalgae and particulate matter) were analysed for stable isotope ratios (δ13C, δ15N). Bayesian mixing model (SIAR) showed a minor contribution of macrophytodetritus while the epiphytic biofilm, present on the macrophytodetritus, appeared to be the major food source of harpacticoid copepods. In order to distinguish the several components of the epiphytic biofilm and their contribution, fatty acid profiling was used. The outcome revealed a general harpacticoid diet preference towards diatoms and bacteria, however specialisation for certain components seemed to reduce competition between harpacticoid species. In conclusion, our results underline the importance of multiple biomarker species-specific analysis, especially in complex and dynamic environments where a wide variety of potential trophic niches are present. [less ▲]

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See detailTurnover rates of carbon and nitrogen stable isotopes in the amphipod Gammarus aequicauda: insights for trophic studies of Mediterranean macrophytodetritus accumulation.
Remy, François ULg; Melchior, Aurélie; Darchambeau, François ULg et al

Conference (2014, August 04)

A quite diverse and abundant macrofauna assemblage is found in the Mediterranean Sea in exported Posidonia oceanica macrophytodétritus accumulations along with meiofauna, microalgae, fungi and bacteria ... [more ▼]

A quite diverse and abundant macrofauna assemblage is found in the Mediterranean Sea in exported Posidonia oceanica macrophytodétritus accumulations along with meiofauna, microalgae, fungi and bacteria. This study focused on a dominant vagile macroinvertebrate species living and feeding in exported dead P.oceanica leaves litter from Calvi Bay (Corsica, France): Gammarus aequicauda. Results of gut content observations and stable isotope analysis (SIAR data) showed clearly that G. aequicauda is the most important dead P. oceanica consumer with up to 50% of dead leaves contribution. An isotopic turnover experiment was conducted with 3 controlled simultaneous treatments: 1. amphipod feeding for 43 days, 2. Green algae feeding for 30 days and 3. Posidonia oceanica litter feeding for 30 days. Individuals (n = 12 to 16) have been sampled every 7 days and whole individual stable isotope analysis have been conducted. An exponential decay regression model and calculations resulted in half-lives for C ranging from 11.72 days (treatment 1) to 51.62 days (treatment 3). Treatment 2 data did not allow us to fit a curve, consequence of a potentially very low turnover rate. For N, no significant increase or decrease of the δ15N values have been observed, and we thus concluded that δ15N was at the equilibrium from the beginning to the end of the experiment. It appears that amphipods feeding on low quality food (high to very high C/N ratio) like algae and Neptune grass dead leaves, show a lower turnover rate for C than amphipods feeding on a high quality animal food (low C/N ratio). Carbon and Nitrogen stable isotope “Trophic Enrichment Factor” (TEF) were calculated for treatments where δ13C or δ15N were at the equilibrium at the end of the experiment. Calculated TEF for nitrogen ranged from 0.53‰ ± 0.439 to 0.96‰ ± 0.424 for treatment 2 and 3 (consistent with detritus-feeder invertebrate values) and was 2.91‰ ± 0.558 for treatment 1 (consistent with predator invertebrate values). For C calculations, a TEF of 0,81‰± 0.39 for treatment 1 and a TEF of 1.19‰ ± 0.824 for treatment 3 were calculated. [less ▲]

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See detailIntraspecific variation of copper tolerance of four endemic plant species from the katangan Copperbelt (D. R. Congo)
Boisson, Sylvain ULg; garin, olivier; Seleck, Maxime ULg et al

Conference (2014, August 04)

Harsh ecosystems are at the origin of speciation processes in plant communities. In metalliferous areas, plants develop physiological adaptations to tolerate metal excesses which lead to high species and ... [more ▼]

Harsh ecosystems are at the origin of speciation processes in plant communities. In metalliferous areas, plants develop physiological adaptations to tolerate metal excesses which lead to high species and population diversity. South of the Katanga province (D.R. Congo), plant communities occur on soils with one of the world’s largest concentrations of copper and cobalt. More than 600 species including 54 endemics are distributed along a copper gradient (up to 10 000 mg kg-1 available Cu) and the populations are isolated on more than 100 copper hills scattered in miombo forest. In order to improve restoration strategies of threatened species, we aimed to identify intraspecific copper tolerance of 4 endemic plant species from katangan copper outcrops: Crotalaria cobalticola, Diplolophium marthozianum, Gladiolus ledoctei and Triumfetta welwitschii. Seeds were collected in 3 different populations in the katangan Copperbelt and sown according three soil contamination modalities: control (no addition of Cu), 100 mg kg-1 and 1000 mg kg-1 of Cu concentration using hydrated copper (II) sulfate. For each combination (species x populations x soils), we had 10 repetitions. For each population, sample of 5 seeds was weighed before seedling in pot in November 2013. One individual by pot was kept for measures. Height (cm), number of leaves, number of flowers and number of fruits were measured once a week during one rainy season. For all species, no significant difference of copper tolerance appeared between populations. In contrast, populations had distinct germination rate and growth rate, especially for T. welwitshii and D. marthozianum. C. cobalticola grew significantly better in highly contaminated soil than other soils. G. ledoctei did not show any significant difference between populations and soil treatments. [less ▲]

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See detailThe instability strip of ZZ Ceti white dwarfs
Van Grootel, Valérie ULg; Fontaine, G.; Brassard, P. et al

Conference (2014, August)

The determination of the location of the theoretical ZZ Ceti instability strip in the log g − Teff diagram has remained a challenge over the years, due to the lack of a suitable treatment for convection ... [more ▼]

The determination of the location of the theoretical ZZ Ceti instability strip in the log g − Teff diagram has remained a challenge over the years, due to the lack of a suitable treatment for convection in these stars. We report here a detailed stability survey over the whole ZZ Ceti regime, including the low and extremely low masses. We computed to this aim 29 evolutionary sequences of DA models with various masses, chemical layering, and core compositions. These models are characterized by the so- called ML2/α=1.0 convective efficiency and take into account the important feedback effect of convection on the atmospheric structure. We computed pulsation spectra for these models with the Liège nonadiabatic pulsation code MAD, which is the only one to conveniently incorporate a full time-dependent convection treatment and, thus, provides the best available description of the blue edge of the instability strip. On the other hand, given the failure of all nonadiabatic codes to account properly for the red edge of the strip, including MAD, we tested the idea that the red edge is due to energy leakage through the atmosphere. Using this approach, we found that our theoretical ZZ Ceti instability strip accounts remarkably well for the boundaries of the empirical strip. [less ▲]

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See detailHow to simulate quickly and efficiently a flow over a spillway ?
Goffin, Louis ULg; Erpicum, Sébastien ULg; Dewals, Benjamin ULg et al

Conference (2014, August)

Flows over hydraulic structures, such as weirs or spillways, can be modelled using different techniques. New models such as SPH or PFEM are becoming more and more popular. These models are particle and/or ... [more ▼]

Flows over hydraulic structures, such as weirs or spillways, can be modelled using different techniques. New models such as SPH or PFEM are becoming more and more popular. These models are particle and/or meshless and consequently require a lot of computational power. Other methods such as VOF also require a lot of computational time. In the frame of 2-D vertical flows, other techniques use much less computation time. For irrotationnal flows, solving the Laplace equation can be done very efficiently. The difficulty of this method lies in the definition of boundary conditions. The free-surface, which is naturally determined when using Lagrangian methods, needs a heavy iterative solving due to its non-linear nature when expressed in the frame of the Laplace equation. This paper will present an original technique that allows a quicker and easier determination of the free-surface. An irregular mesh for boundaries is used and discussed. The method is validated with analytical solutions and experimental measurements. [less ▲]

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See detailModel-Based Computation of Total Stressed Blood Volume from a Preload Reduction Experiment
Pironet, Antoine ULg; Desaive, Thomas ULg; Chase, J. Geoffrey et al

Conference (2014, August)

Total stressed blood volume is an important parameter for both doctors and engineers. From a medical point of view, it has been associated with the success or failure of fluid resuscitation therapy, which ... [more ▼]

Total stressed blood volume is an important parameter for both doctors and engineers. From a medical point of view, it has been associated with the success or failure of fluid resuscitation therapy, which is a treatment for cardiac failure. From an engineering point of view, this parameter dictates the cardiovascular system's dynamic behavior. Current methods to determine this parameter involve repeated phases of circulatory arrests followed by fluid administration. In this work, a method is developed to compute stressed blood volume from preload reduction experiments. A simple six-chamber cardiovascular system model is used and its parameters are adjusted to pig experimental data. The parameter adjustment process has three steps: (1) compute nominal values for all model parameters; (2) determine the most sensitive parameters; and (3) adjust only these sensitive parameters. Stressed blood volume was determined sensitive for all datasets, which emphasizes the importance of this parameter. The model was able to track experimental trends with a maximal mean squared error of 11.77 %. Stressed blood volume has been computed to range between 450 and 963 ml, or 15 to 28 ml/kg, which matches previous independent experiments on pigs, dogs and humans. Consequently, the method proposed in this work provides a simple way to compute total stressed blood volume from usual hemodynamic data. [less ▲]

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See detailAnisotropic resistivity tensor of melt-cast Bi2212 superconductors from QTA
Dellicour, Aline ULg; Vertruyen, Bénédicte ULg; Lutterotti, Luca et al

Conference (2014, August)

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See detailDiplomacia pública, ¿de la teoría a la práctica?: El caso de la Unión Europea en Brasil
Azpíroz Manero, María Luisa ULg

Conference (2014, August)

El entusiasmo académico por la diplomacia pública no se refleja en una atención específica a la misma en las estrategias de política exterior de la Unión Europea (UE). Sin embargo, su presencia se revela ... [more ▼]

El entusiasmo académico por la diplomacia pública no se refleja en una atención específica a la misma en las estrategias de política exterior de la Unión Europea (UE). Sin embargo, su presencia se revela en múltiples iniciativas en las que los agentes no gubernamentales tienen un papel clave como receptores o actores: actividades de cooperación, de intercambio, informativas. La diplomacia pública es una actividad diplomática y de comunicación política internacional que busca influenciar a públicos extranjeros con el fin de contribuir al logro de objetivos de política exterior y/o generar una imagen positiva. Funciona como una herramienta efectiva para movilizar recursos de poder blando, un poder basado en la atracción y la persuasión que se produce de modo indirecto cuando los actores políticos movilizan recursos como la cultura, los valores, las instituciones y las estrategias de política exterior. Pese a la crisis económica, la UE conserva un gran potencial de poder blando. Por eso, y dada la relevancia de Brasil como socio prioritario en la región latinoamericana, este artículo investiga qué diplomacia pública ha desarrollado la UE en este país los últimos tres años, así como su correspondencia con el cuerpo teórico sobre esta actividad. [less ▲]

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See detailThe role of segmentation and investor recognition through the lens of cross-listing activity
Mouchette, Xavier ULg; Muller, Aline ULg; Carrieri, Francesca

Conference (2014, August)

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See detailDeveloping situational judgment tests to assess organizational citizenship behaviours
Lothe, Benoit ULg; Hansez, Isabelle ULg

Conference (2014, August)

a) Purpose As Organizational Citizenship Behaviours (OCBs) positively influence a number of important outcomes (e.g. job performance, unit productivity, organizational efficiency, etc.) and are valued by ... [more ▼]

a) Purpose As Organizational Citizenship Behaviours (OCBs) positively influence a number of important outcomes (e.g. job performance, unit productivity, organizational efficiency, etc.) and are valued by managers as well, Organ, Podsakoff and Podsakoff (2010) assert the need “to try to identify and select those job candidates who have a propensity to exhibit these behaviours” (p.314). This study provides some empirical evidence about using Situational Judgment Tests (SJTs) for this specific target and allows us to discuss the main methodological issues in the development of such SJTs. b) Method Based on relevant best practices and recommendations from the literature (e.g. Weekley, Ployhart & Holtz, 2006), two distinct SJTs were especially developed to comply with OCBs assessment. The two SJTs differ on their job specificity degree (project manager in the industrial sector vs transversal function in the services sector), both propose ten different work related situations and, for each stem, five action proposals are available. Data were collected through online survey on two different samples (220 white collars professionals and 291 university students). Professionals were allowed to choose which SJT they wanted to participate, students were randomized within the two SJTS. An experimental manipulation of the response instructions (ipsative vs normative) was added within the student sample. OCBs were concurrently collected using self-reported measurement scales. c) Results In both samples (respectively professionals and students), the internal consistency was higher for the “job specific” SJT (α = .79 & .81) than for the “transversal job” SJT (α = .49 & 64). Notwithstanding, significant relations were found between the SJT scores and overall OCB ratings for both of the SJT forms in each of the two samples (r ranged from .30 to .57). Other specifics findings also provided substantial evidence for the concurrent validity of the SJTs to measure sub-dimensions of OCBs (altruism, courtesy, civic virtue, sportsmanship, loyalty and voice). d) Conclusions This study is, to our knowledge, the first to address the development and validation of a SJT for the assessment of OCBs. Review of the literature indicates that researches on techniques to predict OCBs are scarce and the present findings appear to surpass the average personality traits validity coefficients (r= .20) according to Organ & al. (2010)’s meta-analysis. There are two main practical implications. The first is the opportunity to use OCBs-SJTs as an alternative to assess applicants OCBs for job-specific or generic personnel selection issue. The second is to provide methodological development advices (e.g. the choice of response instruction) to ensure the SJT match the OCBs assessment requirement. Principal current limitations call for further research development that will be discussed: using different sources of OCBs rating, testing the incremental validity on personality tests, determining whether OCBs-SJTs are correlated with cognitive ability and establishing criterion validity with job performance. [less ▲]

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See detailStructural identifiability analysis of a cardiovascular system model
Pironet, Antoine ULg; Dauby, Pierre ULg; Chase, J. Geoffrey et al

Conference (2014, August)

A simple experimentally validated cardiovascular system model has been shown to be able to track the evolution of various diseases. The model has previously been made patient-specific by adjustment of its ... [more ▼]

A simple experimentally validated cardiovascular system model has been shown to be able to track the evolution of various diseases. The model has previously been made patient-specific by adjustment of its parameters on the basis of a minimal set of hemodynamic measurements. However, this model has not yet been shown to be structurally identifiable, which means that the adjusted model parameters may not be unique. The model equations were manipulated to show that, from a theoretical point of view, all of their parameters can be exactly retrieved from a restricted set of model outputs. However, this set of model outputs is still too large for a clinical application, because it includes left and right ventricular pressures. Consequently, further hypotheses that determine some model parameter values have to be made for the model to be clinically applicable. [less ▲]

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See detailSurvey about diffusion and adoption of glycaemic controller in European intensive care units
Penning, Sophie ULg; Pironet, Antoine ULg; Chase, J. Geoffrey et al

Conference (2014, August)

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See detailComparison of patient's voice quality for T1A glottis carcinoma after endoscopic laser surgery or radiotherapy
Poncelet, Mélanie; DEMEZ, Pierre ULg; Moreau, Pierre ULg et al

Conference (2014, July 30)

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See detailJamming Signal Immunity Tests on GSM-R Communications Compared to EMC Basic Standards
Beauvois, Véronique ULg; Fontana, Michele; Canavero, Flavio et al

Conference (2014, July 29)

This paper presents the work being done in SECRET project (European Program FP7/2007-2013 under grant agreement number “285136”) to strengthen the European rail network against the potential jamming of ... [more ▼]

This paper presents the work being done in SECRET project (European Program FP7/2007-2013 under grant agreement number “285136”) to strengthen the European rail network against the potential jamming of the railway communications. Standardized immunity tests, currently conducted on communication equipment in the presence of electromagnetic (EM) interferences are presented. It then presents the tests carried out in SECRET to assess the resistance of railway communication systems face the signals generated by telecommunication jammers. [less ▲]

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See detailEuropean Union Public Diplomacy through the EEAS: the cases of Argentina, Brazil and Mexico
Azpíroz Manero, María Luisa ULg

Conference (2014, July 25)

Public diplomacy is a promising activity for international political actors to promote a positive image abroad. It also provides opportunities for dialogue, understanding and mutual benefit when ... [more ▼]

Public diplomacy is a promising activity for international political actors to promote a positive image abroad. It also provides opportunities for dialogue, understanding and mutual benefit when communicating and addressing challenges. Within the European Union (EU), the Lisbon Treaty and the European External Action Service (EEAS) have given a new strength to foreign policy. The EEAS, launched in December 2010, is the EU's main institution for public diplomacy. Argentina, Brazil and Mexico are relevant Latin American partners for the EU because of their size, population and political and economic potency in the region. This paper aims to answer the following questions: What is the context of EU relations with Argentina, Brazil and Mexico during the period of study (2011-2013)? What have been the EU's foreign policy and strategies towards these countries? How have public diplomacy and the work of the EEAS in these countries supported the objectives and strategies? This research includes information gained through the consultation of publications, official documents and interviews with personnel from the EEAS, both in Brussels and in the EU delegations in Latin America. [less ▲]

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See detailStreamable Laguerre-Voronoi Tessellation Model for Tomographic Images
Leblanc, Christophe ULg; Nguyen, Van Dung ULg; Wan, Fangyi et al

Conference (2014, July 25)

Introduction. Nowadays, the interest in foam materials is growing in several engineering fields [1]. Foams can exhibit a nonlinear mechanical behavior [2], which is highly depen- dent on their ... [more ▼]

Introduction. Nowadays, the interest in foam materials is growing in several engineering fields [1]. Foams can exhibit a nonlinear mechanical behavior [2], which is highly depen- dent on their microstructure [3]. Thus designing foams with specific mechanical properties can be very challenging. The present contribution is part of the ARC-Bridging project [4], whose objective is to predict the mechanical behavior of complex microstructured mate- rials via numerical simulations. A possible classification of foam models into two groups is: random models and deterministic models [5]. The random models frequently require statistical estimations of their parameters [6], whereas the deterministic models generally require numerically expensive image analyse. Indeed, classical analysis steps involve a distance tranform, a watershed and, optionally, a h-minima transform [5, p. 22], which can be computationally demanding [7, 8, 9]. Contribution. In the present Laguerre–Voronoi tessellation model, the image analysis part neither involes the watershed transform, nor the h-minima transform. Instead, fol- lowing the original idea of A.M. Lopez-Reina et E. Béchet [10], these two transforms are respectively replaced by a Hessian-based removal of spurious extrema and a clustering of the remaining maxima. This substitution allows the processing of large 3D-images by slices, i.e. “streaming”. The only limitation is enforced by the distance transform: the “feature” voxel of a given voxel should belong to the same slice. For foam images, this condition is fulfilled as long as the slice’s thickness is larger than the maximal foam cell’s size. Conclusion and perspectives. The aim of this contribution is to provide an efficient tessellation model for tomographic images of foams. From input tomographic images, this model provides a geometry model which will be used as an input for finite element simulations under the ARC-Briding project [4]. Simulation results will be compared with experimental measures. [less ▲]

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See detailGEOMETRICAL VALIDITY OF HIGH-ORDER PYRAMIDAL FINITE ELEMENTS
Johnen, Amaury ULg; Geuzaine, Christophe ULg

Conference (2014, July 24)

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See detailBrokers and intermediaries in environmental governance, Southern Sri Lanka
Rosillon, Caroline ULg

Conference (2014, July 23)

Since the end of the civil war in 2009, rural Southern Sri Lanka is facing growing tensions between fast economic development and the conservation of biodiversity, which contributes to the notoriety of ... [more ▼]

Since the end of the civil war in 2009, rural Southern Sri Lanka is facing growing tensions between fast economic development and the conservation of biodiversity, which contributes to the notoriety of the island. In order to preserve the green areas of the country, both the government and international institutions have made great efforts to implement projects combining biodiversity protection and poverty reduction as their objectives. Within that context, this paper focuses on a specific category of stakeholders, emerging from the implementation of the aforementioned projects: a wide range of intermediaries between local communities and the State, or international institutions. Based on an ethnographic study of two protected areas in Southern Sri Lanka, the paper will examine the role of those intermediaries in the implementation of environmental governance models and ideologies in local arenas. I will also analyze the complex relationships between those brokers and other categories of individuals or groups within the community: people living in protected areas, traditional figures of power, social and political elites, etc. Using fieldwork illustrations, I will stress how the emergence of brokers and intermediaries in the context of nature conservation may lead to the reorganization of social and political relationships at the local scale. [less ▲]

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See detailDetection of differential item functioning using the lasso approach
Magis, David ULg; Tuerlinckx, Francis; De Boeck, Paul

Conference (2014, July 22)

The purpose of this talk is to present a novel approach to detect differential item functioning (DIF) among dichotomously scored items. Unlike standard DIF methods that perform an item-by-item analysis ... [more ▼]

The purpose of this talk is to present a novel approach to detect differential item functioning (DIF) among dichotomously scored items. Unlike standard DIF methods that perform an item-by-item analysis, we consider a logistic regression model including item-group interaction (i.e. DIF) effects of all items simultaneously. The method is based on penalized maximum likelihood estimation of a model with a lasso penalty on all possible DIF parameters. Optimal penalty parameter selection is investigated through several known information criteria (such as AIC and BIC) as well as a newly developed weighted alternative. A simulation study was conducted to compare the global performance of the suggested “lasso DIF” method to the logistic regression and Mantel-Haenszel methods, and to evaluate the different optimal penalty parameter selection methods. It is concluded that for small samples the lasso DIF approach globally outperforms the logistic regression method, and also the Mantel-Haenszel method, especially in the presence of item impact, while it yields similar results with larger samples. [less ▲]

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See detailSeed dispersal by western lowland gorillas: what about gut passage effect?
Haurez, Barbara ULg; Petre, Charles-Albert ULg; Doucet, Jean-Louis ULg

Conference (2014, July 21)

Animal-mediated seed dispersal is an essential ecological process in the tropics. Among African primates, the critically endangered western lowland gorilla (WLG) seems to fulfill many characteristics of ... [more ▼]

Animal-mediated seed dispersal is an essential ecological process in the tropics. Among African primates, the critically endangered western lowland gorilla (WLG) seems to fulfill many characteristics of an effective seed disperser. WLG preferentially disperses species of various seed-size into open canopy habitats suitable for seedling growth. However, few studies have addressed the effects of the passage through the digestive tract on germination. Thus, the effectiveness of WLG in ecological processes governing forest dynamics and regeneration is still poorly known. Seed dispersal by WLG was studied in Central Gabon and Southeast Cameroon. Dispersed seed were identified from fresh fecal samples. Comparative germination trials based on 5 treatments (seeds from fresh fruits, seeds from fresh fruits surrounded by pulp, seeds from fresh fruits with fecal matrix, seeds from feces and seeds from feces with fecal matrix) were realized for 13 species. We recorded germination success for all species and germination delay for 6 species. Our results suggest a neutral gut passage effect for 54% and positive effect for 40% of tested species. Germination success enhancement was linked to another factor than pulp suppression. For two species, pulp suppression enhanced germination success, but not gut passage. The presence of pulp or fecal matrix surrounding the seed seemed to longer germination delay, while gut passage would not fasten germination. Globally, we conclude that WLG dispersed seeds are not damaged by gut passage. Consequently, WLG is thought to provide effective ecological services that could be essential to the maintenance and the recovery of forest ecosystems. [less ▲]

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See detailThe performance of mobile devices' inertial measurement unit for the detection of cattle's behaviors on pasture
Andriamandroso, Andriamasinoro ULg; Dumont, Benjamin ULg; Lebeau, Frédéric ULg et al

Conference (2014, July 21)

Over the past decade, the Precision Livestock Farming (PLF) concept has taken a considerable place in the development of accurate methods for a better management of farm animals, as Precision Agriculture ... [more ▼]

Over the past decade, the Precision Livestock Farming (PLF) concept has taken a considerable place in the development of accurate methods for a better management of farm animals, as Precision Agriculture has done for crop production. Mass consumption mobile devices have nowadays the possibility to record accurately user movements with their Inertial Measurement Unit (IMU). We used iPhone 4S to detect accurately cattle behaviors such as grazing and ruminating with the aim of performing a precision grazing management on the near future. Results showed accuracies ranging between 84% and 100% when detecting these two major behaviors by analyzing recorded raw signals in the time-domain. Ongoing research tries to link these behaviors to different pasture characteristics and performs a refined signal processing analysis for a better monitoring of some possible behavioral changes. [less ▲]

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