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See detailGeant4 code for gamma spectrometry measurement: a toolkit for Nuclear, Medical, Astronomical and High Energy Physics
Guembou Shouop, Cébastien Joel ULg; Ndontchueng Moyo, Maurice; Nguelem Mekongtso, Eric J. et al

Scientific conference (2017, June)

In the Monte Carlo method, quantities of interest for the application are calculated through statistical sampling of interaction processes. Gamma spectroscopy is a widely used technique, well-illustrated ... [more ▼]

In the Monte Carlo method, quantities of interest for the application are calculated through statistical sampling of interaction processes. Gamma spectroscopy is a widely used technique, well-illustrated by the following list of examples: Environmental Radioactivity Monitoring, nuclear industry, geochemical investigation, and astrophysics. Most radioactive sources produce gamma rays, which are of various energies and intensities. Geant4 (for GEometry ANd Tracking) is a platform for the simulation of the passage of particles through matter, using Monte Carlo methods. The GEANT4 toolkit allows the simulation of the following physical processes: the photo-electrical effect, the Compton Effect, the electron-positron pairs generation and the Rayleigh diffusion. Our study shows the combination of gamma spectrometry, development of related Monte Carlo equation and the presentation of the Geant4 toolkit for gamma spectrometry simulation (simulation of the interaction of gamma photon through matter). It is clearly found, at the end of this study, that Monte-Carlo simulation is a useful, inexpensive alternative that also provides greater flexibility and gained time when determining the detector response and efficiency during an environmental monitoring. [less ▲]

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See detail[18F]BPAM121: An AMPAR Modulator with Potential as a PET Probe
Manos-Turvey, Alexandra ULg; Lemaire, Christian ULg; Deverdenne, François et al

Poster (2017, June)

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See detailGreen mamba peptide targets type-2 vasopressin receptor against polycystic kidney disease
Ciolek, Justyna; Reinfrank, Helen; Quinton, Loïc ULg 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 ▲]

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

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 ULg; Baeten, Vincent; Bodson, Bernard ULg 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 ▲]

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See detailTawada Yoko, "Histoire de Knut": proposition de lecture d'été
Goto, Kanako ULg

Article for general public (2017)

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See detailQu'est-ce que l'eau souterraine ?
Ruthy, Ingrid ULg; Brouyère, Serge ULg

in Eco Karst (2017), 108

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

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See detailLocal Control of AC/DC Converters for Frequency Support Between Asynchronous AC Areas
Papangelis, Lampros ULg; 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 ULg; Van Cutsem, Thierry ULg

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 ▲]

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See detailBalanced sequences of complexity 2n+1
Cassaigne, Julien; Labbé, Sébastien; Leroy, Julien ULg

E-print/Working paper (2017)

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See detailMindfulness in Cyber-Security: The Case of a Government Agency
Tapanainen, Tommi ULg; Lisein, Olivier ULg

Conference (2017, June)

Cyber-security requires not only technical preparations but also organizational practices that reduce the likelihood and severity of damage to the organization. Although user compliance to security ... [more ▼]

Cyber-security requires not only technical preparations but also organizational practices that reduce the likelihood and severity of damage to the organization. Although user compliance to security policies has been examined in prior literature, user behaviour is only one facet of an organization’s cyber-security; the actions of the IT staff, crisis team, and the management are just as critical. Consequently, organizational practices in cyber-security are not understood very well. To address this gap, this research applied the concept of mindfulness, which has recently received attention also in the IT field. We collected data from a revelatory case – that of a government agency that was targeted by a large-scale cyber-attack – and applied the concept of mindfulness in analyzing the data. Our analysis uncovered a number of mindful practices related to cyber-security. These practices can serve as a building block to theorize on the activities to be taken by IT workers in promoting cyber-security. Our paper also suggests avenues for further research in the emerging topic, for instance, through the concept of cyber-security capability. [less ▲]

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See detailUntargeted serum metabolite profiling of colorectal cancer using GC-Orbitrap technology
Di Giovanni, Nicolas ULg; Cojocariu, C; Silcock, P et al

Poster (2017, June)

Detailed reference viewed: 71 (3 ULg)
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See detailLes limites de l’administration de la PCL - R à une population de sujets schizophrènes dans le contexte médico-légal
Englebert, Jérôme ULg; Matteucci, Marie; De Page, Louis et al

Poster (2017, May 31)

Detailed reference viewed: 36 (2 ULg)
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See detailRelations entre nos villes et nos campagnes: quelle place pour l'agriculture?
Bousbaine, Antonia ULg

Conference given outside the academic context (2017)

Nous sommes aujourd'hui confrontés à une urbanisation soutenue de nos campagnes et par voie de conséquences à une diminution drastique du nombre d’exploitations agricoles.Un tournant s'opère dans nos ... [more ▼]

Nous sommes aujourd'hui confrontés à une urbanisation soutenue de nos campagnes et par voie de conséquences à une diminution drastique du nombre d’exploitations agricoles.Un tournant s'opère dans nos sociétés où l'on se doit de faire des choix cruciaux dans nos façons d'appréhender les relations entre nos villes et nos campagnes. Ces choix passent inévitablement par la prise en considération de notre agriculture, qui force est de constater est à bout de souffle.Souhaitons-nous continuer dans le "tout chimique" ou allons-nous réellement devenir consomm 'acteur, en reconsidérant la place de l'agriculture au sein de nos territoires? Ce qui passera par un changement de nos modes de productions, qui se doivent de devenir plus durables, en renouant avec une agriculture à taille humaine qui nourrit sa population [less ▲]

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See detailMulti-instrument study of the hourly pulsations in Saturn's magnetophere
Palmaerts, Benjamin ULg

Doctoral thesis (2017)

The exploration of the magnetospheres of Jupiter and Saturn has revealed various periodic processes. Some periodicities are related to the planetary rotation while some others are characterized by a short ... [more ▼]

The exploration of the magnetospheres of Jupiter and Saturn has revealed various periodic processes. Some periodicities are related to the planetary rotation while some others are characterized by a short period. In Saturn's magnetosphere, periodicities of about one hour have been reported in the measurements of charged particle fluxes, plasma wave emissions, magnetic field strength and auroral emission brightness. The frequency, the spatial distribution and the magnetospheric process generating these hourly periodicities are still unknown. Similar short-period pulsations have been also observed in Jupiter's magnetosphere, suggesting that these 1-hour periodicities are the signature of a fundamental process in the magnetospheres of these two giant planets. In this thesis, I performed a thorough analysis of these hourly periodicities at Saturn using the data sets of several instruments on board the Cassini spacecraft in orbit around the giant planet since 2004. First I made a survey of the quasi-periodic 1-hour energetic electron pulsations observed in Saturn's magnetosphere between 2004 and 2014 by the Cassini particle instrumentation. These pulsations appear in the electron fluxes at energies between a hundred keV up to several MeV. The survey includes 720 pulsed electron events observed in the outer magnetosphere over a wide range of latitudes and local times, revealing that this phenomenon is common and frequent in Saturn's magnetosphere. A statistical analysis on the morphological properties of the pulsed events suggests a high-latitude source for the pulsed energetic electrons. I also investigated the simultaneous signatures of the electron pulsations in the radio emissions and the magnetic field measured by Cassini. The results of the multi-instrument study support the scenario of a high-latitude electron source and suggest a possible relation with the auroral processes. Images of Saturn's auroral emissions, which display the ionospheric response to magnetospheric dynamics, have been investigated to highlight any hourly pulsations. A high-latitude auroral spot exhibits quasi-periodic brightening with a periodicity of around 60 minutes. This auroral spot is associated with the magnetospheric cusp and high-latitude magnetopause reconnection in the lobes. Pulsed dayside magnetopause reconnection is likely a common triggering process for the cusp auroral brightening and for the high-latitude energetic electron pulsations. Finally, analysis of the plasma environment with low-energy electron measurements provided evidence of the presence of energetic electron pulsed events in the close vicinity of the magnetopause. Therefore it is suggested that processes at the magnetopause, most likely magnetic reconnection induced by instabilities, generate the hourly electron pulsations located at low latitude. The multi-instrument study achieved in my thesis sets constraints on the origin of the pulsed electron events and bring forward our current understanding on the hourly pulsations in Saturn's magnetosphere. [less ▲]

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