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See detailL'Eau se retire: le Tsunami arrive
COUCKE, Philippe ULg

in Healthcare Executive (2015), 81

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See detailDoes the soil’s effective hydraulic conductivity adapt in order to obey the Maximum Entropy Production principle? A lab experiment
Westhoff, Martijn ULg; Zehe, Erwin; Erpicum, Sébastien ULg et al

Conference (2015, April)

The Maximum Entropy Production (MEP) principle is a conjecture assuming that a medium is organized in such a way that maximum power is subtracted from a gradient driving a flux (with power being a flux ... [more ▼]

The Maximum Entropy Production (MEP) principle is a conjecture assuming that a medium is organized in such a way that maximum power is subtracted from a gradient driving a flux (with power being a flux times its driving gradient). This maximum power is also known as the Carnot limit. It has already been shown that the atmosphere operates close to this Carnot limit when it comes to heat transport from the Equator to the poles, or vertically, from the surface to the atmospheric boundary layer. To reach this state close to the Carnot limit, the effective thermal conductivity of the atmosphere is adapted by the creation of convection cells (e.g. wind). The aim of this study is to test if the soil’s effective hydraulic conductivity also adapts itself in such a way that it operates close to the Carnot limit. The big difference between atmosphere and soil is the way of adaptation of its resistance. The soil’s hydraulic conductivity is either changed by weathering processes, which is a very slow process, or by creation of preferential flow paths. In this study the latter process is simulated in a lab experiment, where we focus on the preferential flow paths created by piping. Piping is the process of backwards erosion of sand particles subject to a large pressure gradient. Since this is a relatively fast process, it is suitable for being tested in the lab. In the lab setup a horizontal sand bed connects two reservoirs that both drain freely at a level high enough to keep the sand bed always saturated. By adding water to only one reservoir, a horizontal pressure gradient is maintained. If the flow resistance is small, a large gradient develops, leading to the effect of piping. When pipes are being formed, the effective flow resistance decreases; the flow through the sand bed increases and the pressure gradient decreases. At a certain point, the flow velocity is small enough to stop the pipes from growing any further. In this steady state, the effective flow resistance of the sand bed will be compared with the theoretical optimal flow resistance obtained with the MEP principle. For this study, different magnitudes of the forcing will be tested, while also the effect of dry spells will be explored. [less ▲]

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See detailClimatic risk assessment to improve nitrogen fertilisation recommendations : A strategic crop model-based approach
Dumont, Benjamin ULg; Basso, Bruno; Bodson, Bernard ULg et al

in European Journal of Agronomy (2015), 65(10-17),

Within the context of nitrogen (N) management, since 1950, with the rapid intensification of agriculture, farmers have often applied much larger fertiliser quantities than what was required to reach the ... [more ▼]

Within the context of nitrogen (N) management, since 1950, with the rapid intensification of agriculture, farmers have often applied much larger fertiliser quantities than what was required to reach the yield potential. However, to prevent pollution of surface and groundwater induced by nitrates, The European Community launched The European Nitrates Directive 91/6/76/EEC. In 2002, in Wallonia (Belgium), the Nitrates Directive has been transposed under the Sustainable Nitrogen Management in Agriculture Program (PGDA), with the aim of maintaining productivity and revenue for the country’s farmers, while reducing the environmental impact of excessive N application. A feasible approach for addressing climatic uncertainty lies in the use of crop models such as the one commonly known as STICS (simulateur multidisciplinaire pour les cultures standard). These models allow the impact on crops of the interaction between cropping systems and climatic records to be assessed. Comprehensive historical climatic records are rare, however, and therefore the yield distribution values obtained using such an approach can be discontinuous. In order to obtain better and more detailed yield distribution information, the use of a high number of stochastically generated climate time series was proposed, relying on the LARS-Weather Generator. The study focused on the interactions between varying N practices and climatic conditions. Historically and currently, Belgian farmers apply 180 kg N ha−1, split into three equal fractions applied at the tillering, stem elongation and flag-leaf stages. This study analysed the effectiveness of this treatment in detail, comparing it to similar practices where only the N rates applied at the flag-leaf stage were modified. Three types of farmer decision-making were analysed. The first related to the choice of N strategy for maximising yield, the second to obtaining the highest net revenue, and the third to reduce the environmental impact of potential N leaching, which carries the likelihood of taxation if inappropriate N rates are applied. The results showed reduced discontinuity in the yield distribution values thus obtained. In general, the modulation of N levels to accord with current farmer practices showed considerable asymmetry. In other words, these practices maximised the probability of achieving yields that were at least superior to the mean of the distribution values, thus reducing risk for the farmers. The practice based on applying the highest amounts (60–60–100 kg N ha−1) produced the best yield distribution results. When simple economical criteria were computed, the 60–60–80 kg N ha−1 protocol was found to be optimal for 80–90% of the time. There were no statistical differences, however, between this practice and Belgian farmers’ current practice. When the taxation linked to a high level of potentially leachable N remaining in the soil after harvest was considered, this methodology clearly showed that, in 3 years out of 4, 30 kg N ha−1 could systematically be saved in comparison with the usual practice. [less ▲]

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See detailSeismic hazard assessment of the Kivu rift segment based on a new sismo-tectonic zonation model (Western Branch of the East African Rift system)
Havenith, Hans-Balder ULg; Delvaux, Damien

in EGU General Assembly Conference Abstracts (2015, April)

In the frame of the Belgian GeoRisCA multi-risk assessment project focused on the Kivu and Northern Tanganyika Region, a seismic hazard map has been produced for this area. It is based on a on a recently ... [more ▼]

In the frame of the Belgian GeoRisCA multi-risk assessment project focused on the Kivu and Northern Tanganyika Region, a seismic hazard map has been produced for this area. It is based on a on a recently re-compiled catalogue using various local and global earthquake catalogues. The use of macroseismic epicenters determined from felt earthquakes allowed to extend the time-range back to the beginning of the 20th century, thus spanning about 100 years. The magnitudes have been homogenized to Mw and the coherence of the catalogue has been checked and validated. The seismo-tectonic zonation includes 10 seismic source areas that have been defined on the basis of the regional geological structure, neotectonic fault systems, basin architecture and distribution of earthquake epicenters... [less ▲]

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See detailLa mémoire manipulée - les faux souvenirs et les faux aveux sont-ils possibles?
Dehon, Hedwige ULg

Article for general public (2015)

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

Poster (2015, April)

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

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

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See detailAgonistic sounds and swim bladder morphology in a malapterurid electric catfish
Boyle, Kelly; Bolen, Géraldine ULg; Parmentier, Eric ULg

in Journal of Zoology (2015)

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See detailParty autonomy in international family relationships : a research agenda
Wautelet, Patrick ULg

E-print/Working paper (2015)

In recent years, party autonomy has conquered new grounds in cross-border private relationships. Building on first attempts in national codifications, party autonomy has become one of the leading ... [more ▼]

In recent years, party autonomy has conquered new grounds in cross-border private relationships. Building on first attempts in national codifications, party autonomy has become one of the leading principles used in various EU regulations dealing with cross-border family relationships. It can now be found in successions, in divorce, in maintenance matters. This new trend has been greeted sometimes with enthusiasm, sometimes with skepticism. While these Regulations constrain the choice that parties can make, it cannot be denied that the principle of freedom of choice has been openly embraced by the European legislator. Hence this principle evolved, at least within the EU, from what was until recently a marginal phenomenon to a well-respected solution for cross-border family relationships This (r-)evolution occurred quite fast and has attracted much attention. However, much of the research in this area has adopted a limited perspective, focusing exclusively on the possibilities and limits of choice in one specific instrument or adopting a comprehensive outlook but with a strong positive flavor. While it is true that a number of contributions provide excellent food for thought, the overall impression is that more time and more research is needed to start apprehending the fundamental questions raised by this evolution. At this stage, it may be too early to offer a comprehensive study of all questions raised by party autonomy in private international law. New developments may in fact modify the picture soon and add to the fields conquered by party autonomy. At the same time, the relative novelty of the changes makes it difficult to take full stock of all issues raised by the development of party autonomy. This is why scholars should first attempt to define a research agenda. This paper offers a first scratch by exploring various questions which should figure prominently in such agenda. It is by no means meant to be exhaustive. Rather, an attempt will be made to shed some light on the main questions raised by recent evolution in the hope of being an invitation for further research. [less ▲]

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See detailComparer et articuler les droits. L'exemple du démariage en 2015
Wautelet, Patrick ULg

in Droit de la famille (2015), 20(4), 63-66

Cette communication dresse un tableau succincts de l'état du droit comparé du divorce en Europe. L'analyse de droit comparé sert d'appui à une mise en perspective du droit international privé du divorce.

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See detailBiogenic Volatile Organic Compound (BVOC) emissions from agricultural crop species: is guttation a possible source for methanol emissions following light/dark transition?
Mozaffar, Ahsan ULg; Amelynck, Crist; Bachy, Aurélie ULg et al

in Geophysical Research Abstracts (2015, April), 17(EGU2015-2110-1),

In the framework of the CROSTVOC (CROp STress VOC) project, the exchange of biogenic volatile organic compounds (BVOCs) between two important agricultural crop species, maize and winter wheat, and the ... [more ▼]

In the framework of the CROSTVOC (CROp STress VOC) project, the exchange of biogenic volatile organic compounds (BVOCs) between two important agricultural crop species, maize and winter wheat, and the atmosphere has recently been measured during an entire growing season by using the eddy covariance technique. Because of the co-variation of BVOC emission drivers in field conditions, laboratory studies were initiated in an environmental chamber in order to disentangle the responses of the emissions to variations of the individual environmental parameters (such as PPFD and temperature) and to diverse abiotic stress factors. Young plants were enclosed in transparent all-Teflon dynamic enclosures (cuvettes) through which BVOC-free and RH-controlled air was sent. BVOC enriched air was subsequently sampled from the plant cuvettes and an empty cuvette (background) and analyzed for BVOCs in a high sensitivity Proton-Transfer Reaction Mass Spectrometer (hs-PTR-MS) and for CO2 in a LI-7000 non-dispersive IR gas analyzer. Emissions were monitored at constant temperature (25 °C) and at a stepwise varying PPFD pattern (0-650 µmol m-2 s-1). For maize plants, sudden light/dark transitions at the end of the photoperiod were accompanied by prompt and considerable increases in methanol (m/z 33) and water vapor (m/z 39) emissions. Moreover, guttation droplets appeared on the sides and the tips of the leaves within a few minutes after light/dark transition. Therefore the assumption has been raised that methanol is also coming out with guttation fluid from the leaves. Consequently, guttation fluid was collected from young maize and wheat plants, injected in an empty enclosure and sampled by PTR-MS. Methanol and a large number of other compounds were observed from guttation fluid. Recent studies have shown that guttation from agricultural crops frequently occurs in field conditions. Further research is required to find out the source strength of methanol emissions by this guttation phenomenon in real environmental conditions. [less ▲]

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See detailPrélèvements fiscaux et prestations sociales en Belgique: l'impact de vingt années de réformes
Decoster, André; Perelman, Sergio ULg; Vandelannoote, Dieter et al

in Revue Française d'économie (2015), 24

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See detailMédicaments: Faux et usage de faux
Sacre, Pierre-Yves ULg; Marini Djang'Eing'A, Roland ULg; Ziemons, Eric ULg et al

Article for general public (2015)

La contrefaçon des médicaments est en constante progression, voire en pleine explosion. Chaque année, elle tue des centaines de milliers de personnes, principalement en Afrique. Véritable fléau, elle est ... [more ▼]

La contrefaçon des médicaments est en constante progression, voire en pleine explosion. Chaque année, elle tue des centaines de milliers de personnes, principalement en Afrique. Véritable fléau, elle est de plus en plus souvent aux mains de réseaux transnationaux d'une profonde opacité. [less ▲]

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See detailA novel procedure to measure shrinkage-free tree-rings from very large wood samples combining photogrammetry, high-resolution image processing, and GIS tools
Latte, Nicolas ULg; Beeckman, Hans; Bauwens, Sébastien ULg et al

in Dendrochronologia (2015), 34

We present a new procedure for wood sampling and tree-ring measurement that can be used for dendrochronological investigation on very large trees, specifically adapted for tropical rainforest species ... [more ▼]

We present a new procedure for wood sampling and tree-ring measurement that can be used for dendrochronological investigation on very large trees, specifically adapted for tropical rainforest species. This procedure takes advantage of the technological developments in computing, image processing, and geographic information systems (GIS) to overcome the technical limitations of the currently used methods. Two types of wood samples can be used (stem disks and/or bars) depending on tree diameter, and the difficulty of ring delineation and crossdating. Bars are an effective compromise between cores and disks. We developed an application combining several programs (Excel, R, ArcGIS, and MapWinGIS) in the Windows operating system for semi-automatic measurement of tree-rings from high-resolution images of the sanded cross-section. Using an innovative method to reverse the wood shrinkage resulting from the drying process, tree-ring measurement can be performed on shrinkage-free images, thus referring to the actual growth of the tree. [less ▲]

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See detailTowards a Middlebox Policy Taxonomy: Path Impairments
Edeline, Korian ULg; Donnet, Benoît ULg

in International Workshop on Network Science for Communication Networks (NetSciCom): Hong Kong April 27 2015 (2015, April)

Recent years have seen the rise of middleboxes, such as firewalls, NATs, proxies, or Deep Packet Inspectors. Those middleboxes play an important role in today's Internet, including enterprise networks and ... [more ▼]

Recent years have seen the rise of middleboxes, such as firewalls, NATs, proxies, or Deep Packet Inspectors. Those middleboxes play an important role in today's Internet, including enterprise networks and cellular networks. However, despite their huge success in modern network architecture, they have a negative impact on the Internet evolution as they can slow down the TCP protocol evolution and its extensions. Making available a summary of the potential middlebox network interferences is of the highest importance as it could allow researchers to confront their new transport protocol to potential issues caused by middleboxes. And, consequently, allowing again innovation in the Internet. This is exactly what we tackle in this paper. We propose a path impairment oriented middlebox taxonomy that aims at categorizing the initial purpose of a middlebox policy as well as its potential unexpected complications. Based on a measurement campaign on IPv4 and IPv6 networks, we confront our taxonomy to the real world. Our dataset is freely available. [less ▲]

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See detailEnseignement des langues étrangères et interculturalité
Defays, Jean-Marc ULg

Scientific conference (2015, April)

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See detailAccess to human tissues for research and product development
Pirnay, Jean‐Paul; BAUDOUX, Etienne ULg; Cornu, Olivier et al

in EMBO Reports (2015)

Detailed reference viewed: 23 (7 ULg)