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See detailSeparation of FLEC diastereomers by CE vs. LC approaches in the context of neurometabolomics
Moldovan, Radu-Cristian ULiege; Bodoki, Ede; Servais, Anne-Catherine ULiege et al

Poster (2017, June)

Some of the D-amino acids (D-Ser, D-Asp, D-Glu) have gained an increasing attention during the last decades, due to the discovery of their role as neurotransmitters and their implication in different ... [more ▼]

Some of the D-amino acids (D-Ser, D-Asp, D-Glu) have gained an increasing attention during the last decades, due to the discovery of their role as neurotransmitters and their implication in different neurological pathologies (Alzheimer’s disease, schizophrenia etc.). Nevertheless, their use as biomarkers is particularly relevant when correlated with the levels of other neurotransmitters. In order to develop a fast and efficient separation method widely accessible for the quantitation of these molecules, we used only common separation tools such as RP-18 stationary phases for reversed phase liquid chromatography (RP-LC) or bare fused capillaries for capillary zone electrophoresis (CZE). For achieving chiral resolution, a derivatization procedure was implemented. (-)-FLEC was the chiral derivatization agent of choice due to its fast and quantitative reaction with primary and secondary amines and the ability of performing in-capillary derivatization. Moreover, the derivatization process implies only a simple mix of the sample and reagent, at room temperature. The separation of the FLEC derivatives of several biologically relevant D- and L- amino acids (Asp, Glu, Ser, Tyr, Trp, Phe, His) together with certain neurotransmitter molecules have been optimized using CZE or RP-LC, chiral resolution being achievable for all amino acids of interest. By the CZE approach the running buffer’s pH turned out to be critical in achieving baseline separation of the targeted analytes. The derivatives of most amino acids could be separated using 60mM acetate buffer at pH 5, while for Asp derivatives the separation could be achieved only at pH 4. Being stronger bases, a third run at a more alkaline pH was needed for the separation of the remainder neurotransmitters. Moreover, the implemented in-capillary derivatization allows a fast and fully automated separation procedure. As for the RP-LC approach 50 mM acetate buffer in combination with an organic modifier (methanol, acetonitrile or tetrahydrofuran (THF)) was tested as mobile phase using gradient elution. Once again, the strong influence of pH on the resolution was observed. The organic modifier nature was of critical importance, where only THF enabled baseline resolution for all amino acid derivatives. [less ▲]

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See detailEuropean silver eel (Anguilla anguilla L.) migration behaviour in a highly regulated shipping canal
Verhelst, Pieterjan; Baeyens, Raf; Buysse, David et al

Conference (2017, June)

Over the last 40 years, Anguilla species in the northern hemisphere have shown a strong decline in recruitment. Due to a 98% recruitment decline, the European eel is now classified as critically ... [more ▼]

Over the last 40 years, Anguilla species in the northern hemisphere have shown a strong decline in recruitment. Due to a 98% recruitment decline, the European eel is now classified as critically endangered according to the IUCN Red List. To aid conservation and recovery of European eel populations, the European Union recently adopted a Council Regulation which imposes a management system that ensures 40% escapement of the spawning stock biomass, defined as the best estimate of the theoretical escapement rate if the stock were completely free of anthropogenic influences. Various causes likely contribute to the eel decline (e.g. pollution, human-introduced parasites, changes in ocean climate, habitat deterioration…), but habitat fragmentation by migration barriers that prevent the movement of silver eels between freshwater and the sea is probably one of the most important bottlenecks. During the last decades, a substantial number of canals has been developed, creating new habitat for eels. However, eel migration and potential obstacles in these systems are still underexplored. In this study, we tracked 131 European eels (Anguilla anguilla L.) from October 2014 till March 2017 in the Belgian Albert Canal with acoustic telemetry. The 130-km long canal is on average 86 m wide, 5 m deep and functions as a shipping route between the rivers Schelde and Meuse. The canal has a highly regulated water flow and six shipping locks to overcome the 56-m fall, which may have a negative impact on silver eel escapement. Indeed, we found significant delays (i.e. periods with a significantly prolonged residence time) and a ca 50% lower swimming speed near shipping locks compared to riverine conditions. Depending on nothing but their accumulated fat for migration to their spawning grounds, delays can seriously impact eels by wasting precious energy resources needed for a successful trans-Atlantic migration. [less ▲]

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See detailAnycast-based DNS in Mobile Networks
Wassermann, Sarah ULiege

Master's dissertation (2017)

Anycast offers a method for making a service IP address available to a routing system from several locations at once. It is used today to provide important services, such as naming and content delivery ... [more ▼]

Anycast offers a method for making a service IP address available to a routing system from several locations at once. It is used today to provide important services, such as naming and content delivery, in an economic, scalable, and simple to operate manner. The appeal and clear benefits of anycast to service providers have motivated a number of recent experimental studies on its potential performance impact. All studies have, to the best of our knowledge, focused on wired networks, despite the growing dominance of mobile as the most common and sometimes only form of Internet access. In this thesis, we present the first study of anycast performance for mobile users. In particular, our evaluation focuses on three distinct anycast services: K- and F-Root, each providing part the DNS root zone, and Google DNS. Our research revolves around three axes. First, we show that mobile clients are frequently routed to suboptimal replicas in terms of latency and that this issue is not limited to specific regions or ASes of the world. Second, we find that clients are often redirected to a DNS server hosted very far away from her. This happens more frequently while on a cellular connection than on WiFi, with a significant impact on performance. Our study reveals that this is not simply an issue of not having better alternatives, and that the problem is not localised to particular geographic areas or particular ASes. We investigate root causes of this phenomenon and describe three of the major detected classes of anycast anomalies. Third and finally, we explore IP assignment dynamics of mobile clients and find that recurrent IP changes on the client side lead to significant perceived variations of anycast latency. [less ▲]

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See detailPercepire la sofferenza degli animali. Fondamenti per un’empatia interspecifica
Servais, Véronique ULiege

in Animal Studies (2017), 17

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See detailMaladie coronaire et pratique sportive
ANCION, Arnaud ULiege; KAUX, Jean-François ULiege; PIERARD, Luc ULiege et al

in Revue Médicale de Liège (2017), 72(6), 281-287

Detailed reference viewed: 47 (8 ULiège)
See detailCrossoads ( juin 2017) - chaque mercredi de 18h à20h - rediffusion: samedis de 22h à minuit
Sacré, Robert ULiege

Diverse speeche and writing (2017)

Programme radio hebdomadaire consacré aux musiques africaines-américaines ; streaming : www.equinoxefm.be ; podcasts www.mixcloud.com/robertsacre9

Detailed reference viewed: 10 (0 ULiège)
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See detailROOF STACKING: Learned Lessons from Architects
Amer, Mohamed ULiege; Attia, Shady ULiege

Report (2017)

Roof Stacking represents an approach to accommodate increasing population in the major cities around Europe, new agendas for urban densification emerge in response of finding sustainable solutions to use ... [more ▼]

Roof Stacking represents an approach to accommodate increasing population in the major cities around Europe, new agendas for urban densification emerge in response of finding sustainable solutions to use existing urban infrastructure in the most efficient ways. Several methods for urban densification are being proposed and seen in real life. One of those methods is roof stacking, which is defined as the added structure over the rooftop of an existing building to create one or more stories of living spaces. This report represents the results of conducted investigation on roof stacking method as a sustainable approach for urban densification. The aim of this report is to present a guideline for roof stacking construction approaches and methods and present the learned lessons through interviewing notable architects from different European countries who applied roof stacking. This report identifies the challenges and opportunities when applying roof stacking in addition to proposing recommended solution for the different obstacles that are faced when adding extensions on the rooftops. [less ▲]

Detailed reference viewed: 64 (25 ULiège)
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See detailPressure-induced insulator–metal transition in EuMnO3
Qiu, Ruihao ULiege; Bousquet, Eric ULiege; Cano, Andres

in Journal of Physics : Condensed Matter (2017), 29

We study the influence of external pressure on the electronic and magnetic structure of EuMnO3 from first-principles calculations. We find a pressure-induced insulator– metal transition at which the ... [more ▼]

We study the influence of external pressure on the electronic and magnetic structure of EuMnO3 from first-principles calculations. We find a pressure-induced insulator– metal transition at which the magnetic order changes from A-type antiferromagnetic to ferromagnetic with a strong interplay with Jahn–Teller distortions. In addition, we find that the non-centrosymmetric E*-type antiferromagnetic order can become nearly degenerate with the ferromagnetic ground state in the high-pressure metallic state. This situation can be exploited to promote a magnetically-driven realization of a non-centrosymmetric (ferroelectric-like) metal. [less ▲]

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See detailGreen mamba peptide targets type-2 vasopressin receptor against polycystic kidney disease
Ciolek, Justyna; Reinfrank, Helen; Quinton, Loïc ULiege et al

in Proceedings of the National Academy of Sciences of the United States of America (2017)

Polycystic kidney diseases (PKDs) are genetic disorders that can cause renal failure and death in children and adults. Lowering cAMP in cystic tissues through the inhibition of the type-2 vasopressin ... [more ▼]

Polycystic kidney diseases (PKDs) are genetic disorders that can cause renal failure and death in children and adults. Lowering cAMP in cystic tissues through the inhibition of the type-2 vasopressin receptor (V2R) constitutes a validated strategy to reduce disease progression. We identified a peptide from green mamba venom that exhibits nanomolar affinity for the V2R without any activity on 155 other G-protein–coupled receptors or on 15 ionic channels. Mambaquaretin-1 is a full antagonist of the V2R activation pathways studied: cAMP production, beta-arrestin interaction, and MAP kinase activity. This peptide adopts the Kunitz fold known to mostly act on potassium channels and serine proteases. Mambaquaretin-1 interacts selectively with the V2R through its first loop, in the same manner that aprotinin inhibits trypsin. Injected in mice, mambaquaretin-1 increases in a dose-dependent manner urine outflow with concomitant reduction of urine osmolality, indicating a purely aquaretic effect associated with the in vivo blockade of V2R. CD1-pcy/pcy mice, a juvenile model of PKD, daily treated with 13 μ𝝁g of mambaquaretin-1 for 99 d, developed less abundant (by 33%) and smaller (by 47%) cysts than control mice. Neither tachyphylaxis nor apparent toxicity has been noted. Mambaquaretin-1 represents a promising therapeutic agent against PKDs. [less ▲]

Detailed reference viewed: 44 (5 ULiège)
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See detailDesigning institutions for collective energy action: the roles of renewable energy cooperatives in a polycentric low-carbon transition
Bauwens, Thomas ULiege

Doctoral thesis (2017)

The process of climate change mitigation and the transition toward low-carbon energy systems associated with it are probably the greatest collective action problems humankind has ever confronted ... [more ▼]

The process of climate change mitigation and the transition toward low-carbon energy systems associated with it are probably the greatest collective action problems humankind has ever confronted. According to the conventional theory of collective action, rational agents pursuing their own interest will not participate in collective efforts because they have incentives to free-ride on the constructive behavior of others. More recently, various authors have argued that complex collective action problems faced by large groups, such as climate change mitigation, are often decomposable into social dilemmas at a smaller scale, some of which are more easily surmountable given pre-existing social norms and trust networks. Accordingly, community-based energy (CBE) projects have been perceived as ideal institutional models to foster pro-environmental attitudes and behaviors. However, the analytical scrutiny of CBE projects is scarce. The main purpose of this dissertation is thus to assess the potential roles CBE projects may play in a low-carbon transition, focusing on the case of renewable energy (RE) cooperatives. First, the thesis examines how cooperative membership relates to three outcomes of interest: financial investments in cooperatives, attitudes toward RE and wind energy technologies, and electricity consumption behaviors, based on quantitative empirical evidence from Flanders. Regarding financial investments in the organizations, the results show that several categories of members with different motives and levels of engagement can be distinguished. This heterogeneity is explained by contrasts in terms of institutional settings, spatial patterns and attitudes to the diffusion of institutional innovations. In addition, social identification to the cooperative and a dense social network structure have a significant positive effect on financial contributions. Regarding attitudes toward renewable energy technologies and onshore wind energy in particular, our results suggest that the main difference between members and non-members is that the latter are not more opposed to wind energy than the former, but are actually more indifferent. Significant differences among cooperative members are also highlighted, illustrating their heterogeneity. As for energy consumption practices, it is shown that electricity consumption is positively related with cooperative membership, suggesting that high use consumers have greater incentives to join a community-based organization which provides assistance and advice on the adoption of green technologies and energy efficiency measures. Second, the thesis seeks to analyze how the direct institutional and physical contexts influence cooperative members’ decisions and behaviors. The distinction between ‘mutual’ and ‘public’ benefit organizations and the spatial patterns of the projects developed by cooperatives are emphasized. The findings reveal that an orientation toward mutual benefit is associated with lower social identification to the cooperative and weaker ties between members as compared to an orientation toward public benefit. Spatial patterns also play a significant role. Indeed, members who are more spatially concentrated have more social interactions with fellow members, identify more strongly to their cooperative and are more pro-environmentally oriented. Third, the research connects these empirical findings at the local level with perspectives at higher levels in order to shed some light on the conditions of emergence of RE cooperatives. A qualitative comparison between Belgium, the UK, Germany and Denmark emphasizes the contextual factors that facilitate or hinder the creation and development of RE cooperatives at the national level. The comparison highlights a double-edged phenomenon: prevailing and growing hostility towards cooperatives, on the one hand, and, on the other, strategic reactions to this evolution. What comes out indeed is that, throughout most of these countries, the emergence of some coordinated inter-organizational actions among cooperatives enables them to survive in their critical environment. [less ▲]

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See detailQuantification of roots by the use of NIR hyperspectral imaging and chemometrics
Eylenbosch, Damien ULiege; Baeten, Vincent; Bodson, Bernard ULiege et al

Poster (2017, June)

Roots, the belowground part of plants, play a major role in plant development. Their study in field conditions is important to identify suitable soil management practices for suitable crop production but ... [more ▼]

Roots, the belowground part of plants, play a major role in plant development. Their study in field conditions is important to identify suitable soil management practices for suitable crop production but roots are hidden by soil and their study is therefore difficult. Estimation of root system development is often based on the soil coring method which allows repeated measurements during the growing season in the field as well as in different soil horizons. However, this method is limited due to the time needed to extract roots from soil cores and to manually sort them from crop residues before quantification. To avoid this tedious sorting step and remove operator subjectivity, a faster sorting method was developed. Near infrared hyperspectral imaging (NIR-HIS) was tested as a rapid method to quantify the amount of roots in soil samples. [less ▲]

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See detailSartre, hériter de Heidegger ? Quelques remarques à propos du circuit de l'ipséité dans "L'Être et le Néant" [titre provisoire]
Recchia, Fabio ULiege

in Revista Ética e Filosofia Política (2017), 1

Il n’est en philosophie d’héritage que gagné. Et en m’installant dans cette ambigüité propre au savoir philosophique, j’examine, dans ce texte, un développement peu étudié de la pensée sartrienne : sa ... [more ▼]

Il n’est en philosophie d’héritage que gagné. Et en m’installant dans cette ambigüité propre au savoir philosophique, j’examine, dans ce texte, un développement peu étudié de la pensée sartrienne : sa théorie du « circuit de l’ipséité » de la conscience. Quant à mon objectif, il s’agira de faire le point sur le processus de maturation intellectuelle à l’issue duquel Sartre conçut l’ipséité comme un circuit. Ainsi je mets en évidence que certaines des réflexions de Heidegger, Bergson et Mauss, sur la notion d’identité personnelle ont constitué les héritages philosophiques mobilisés et transformés par la théorie sartrienne de l’ipséité. [less ▲]

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See detailQuantification of roots by the use of NIR hyperspectral imaging and chemometrics
Eylenbosch, Damien ULiege; Baeten, Vincent; Bodson, Bernard ULiege et al

Conference (2017, June)

Estimation of root system development is often based on the soil coring method which allows repeated measurements during the growing season in the field as well as in different soil horizons. However ... [more ▼]

Estimation of root system development is often based on the soil coring method which allows repeated measurements during the growing season in the field as well as in different soil horizons. However, this method is limited due to the time needed to extract roots from soil cores and to manually sort them from crop residues before quantification. To avoid this tedious sorting step and remove operator subjectivity, a procedure based on NIR Hyperspectral Imaging (NIR-HSI) has been developed. [less ▲]

Detailed reference viewed: 31 (1 ULiège)
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See detailTawada Yoko, "Histoire de Knut": proposition de lecture d'été
Goto, Kanako ULiege

Article for general public (2017)

Detailed reference viewed: 27 (4 ULiège)
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See detailQu'est-ce que l'eau souterraine ?
Ruthy, Ingrid ULiege; Brouyère, Serge ULiege

in Eco Karst (2017), 108

L'eau souterraine et le karst. Quelques définitions et concepts-clés

Detailed reference viewed: 18 (2 ULiège)
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See detailLocal Control of AC/DC Converters for Frequency Support Between Asynchronous AC Areas
Papangelis, Lampros ULiege; Debry, Marie-Sophie; Panciatici, Patrick et al

in IEEE PES 2017 PowerTech conference proceedings (2017, June)

This paper proposes a novel control scheme for frequency support among asynchronous AC areas through HVDC grids. It is based on local controllers, each acting on a voltage source converter, using locally ... [more ▼]

This paper proposes a novel control scheme for frequency support among asynchronous AC areas through HVDC grids. It is based on local controllers, each acting on a voltage source converter, using locally available measurements only, and supporting frequency of the adjacent AC area after a significant disturbance. The controller is combined with the existing DC voltage droop technique and is inspired of Model Predictive Control, taking into account various constraints. The coordination of the proposed control scheme with the existing secondary frequency control of an AC area is also discussed. Examples obtained from a test system with a five-terminal DC network connecting two asynchronous areas demonstrate the effectiveness of the proposed control scheme. [less ▲]

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See detailVoltage Profile Correction in Distribution Grids Combining Single- and Two-level Controllers
Soleimani Bidgoli, Hamid ULiege; Van Cutsem, Thierry ULiege

in IEEE PES 2017 PowerTech conference proceedings (2017, June)

A real-time control scheme is proposed to correct undesired voltages in distribution networks by adjusting the reactive powers produced by Dispersed Generation Units (DGUs). This is performed at two ... [more ▼]

A real-time control scheme is proposed to correct undesired voltages in distribution networks by adjusting the reactive powers produced by Dispersed Generation Units (DGUs). This is performed at two levels: locally, in DGU controllers, and centrally by a supervisory controller acting on some of the DGUs only. The centralized, discrete controller solves a multi-time-step constrained optimization inspired of Model Predictive Control. Unacceptable voltage deviations are partially but rapidly corrected by the local controls. Further but slower corrections are applied by the upper level, taking advantage of the coordination between DGUs. This hybrid control is of practical interest where the deployment of the upper level control is not feasible or affordable over all DGUs. The proposed method effectiveness is demonstrated on a 75-bus test system. [less ▲]

Detailed reference viewed: 42 (18 ULiège)
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See detailBalanced sequences of complexity 2n+1
Cassaigne, Julien; Labbé, Sébastien; Leroy, Julien ULiege

E-print/Working paper (2017)

Detailed reference viewed: 19 (1 ULiège)