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See detailIsolation, Purification, and Cultivation of Toxigenic Cyanobacteria
Haande, Sigrid; Jasser, Iwona; Gugger, Muriel et al

in Kurmayer, Rainer; Sivonen, Kaarina; Wilmotte, Annick (Eds.) et al Molecular Tools for the Detection and Quantification of Toxigenic Cyanobacteria (2017)

This chapter summarizes the most commonly used methods for the isolation, purification, and cultivation of toxic cyanobacteria. The aim is to give general advice on how to isolate and maintain clonal ... [more ▼]

This chapter summarizes the most commonly used methods for the isolation, purification, and cultivation of toxic cyanobacteria. The aim is to give general advice on how to isolate and maintain clonal cyanobacterial cultures in order to use them in genetic studies. The traditional methods for the isolation of cyanobacteria into culture are well established and described and there are several excellent reviews with detailed information on culturing techniques [less ▲]

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See detailTesting revealed preference: An algorithmic outlook
Smeulders, Bart ULg; Crama, Yves ULg; Spieksma, Frits C.R.

E-print/Working paper (2017)

Revealed preference theory is a domain within economics that studies rationalizability of behavior by (certain types of) utility functions. Given observed behavior in the form of choice data, testing ... [more ▼]

Revealed preference theory is a domain within economics that studies rationalizability of behavior by (certain types of) utility functions. Given observed behavior in the form of choice data, testing whether certain conditions are satisfied gives rise to a variety of computational problems that can be analyzed using operations research techniques. In this survey, we provide an overview of these problems, their theoretical complexity, and available algorithms for tackling them. We focus on consumer choice settings, in particular individual choice, collective choice and stochastic choice settings. [less ▲]

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See detailDNA (Diagnostic) and cDNA Microarray
Rantala-Yilinen, Anne; Sivonen, Kaarina; Wilmotte, Annick ULg

in Kurmayer, Rainer; Sivonen, Kaarina; Wilmotte, Annick (Eds.) et al Molecular Tools for the Detection and Quantification of Toxigenic Cyanobacteria (2017)

Diagnostic microarrays have been used to study cyanobacterial diversity in environmental samples. They usually include sequences (probes) for only one or a few genes allowing a number of genera/species to ... [more ▼]

Diagnostic microarrays have been used to study cyanobacterial diversity in environmental samples. They usually include sequences (probes) for only one or a few genes allowing a number of genera/species to be detected. In contrast, cDNA microarrays are used for screening genome-wide changes in gene expression and include probes for all or most genes in one strain . The purpose of this sub-chapter is to introduce the principle of a diagnostic microarray (= DNA chip) that uses a ligation detection reaction (LDR) and universal microarray to simultaneously detect and identify all potential microcystin and nodularin producers present in a sample. This is especially useful when monitoring environmental samples that can contain many cyanobacterial genera, including toxin-producing strains. [less ▲]

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See detailMéditations expérimenées sur la TSUM (Transition Secondaire-Université en Mathématiques)
Bair, Jacques ULg

E-print/Working paper (2017)

L’objectif de ce travail est de mettre par écrit quelques idées personnelles à propos de l’enseignement des mathématiques dans une première année de l’enseignement supérieur et ainsi de réfléchir à propos ... [more ▼]

L’objectif de ce travail est de mettre par écrit quelques idées personnelles à propos de l’enseignement des mathématiques dans une première année de l’enseignement supérieur et ainsi de réfléchir à propos de la transition entre le secondaire et l’Université (TSU, en abrégé) pour un cours de mathématiques. A cet effet, on compare les enseignements secondaire et universitaire, on précise une certaine conception des mathématiques et de leur enseignement au niveau de la TSU. Dans une première annexe se trouve également une étude plus théorique et technique sur la métacognition. Une particularité de ce travail est probablement de relier des idées issues de la littérature spécialisée relative à trois thèmes qui sont souvent développés indépendamment les uns des autres, à savoir l’épistémologie des mathématiques, la pédagogie universitaire et la didactique des mathématiques, le tout étant agencé d’après des convictions personnelles et des expériences professionnelles. [less ▲]

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See detailAssessing quality of life using structural equation modeling
Dardenne, Nadia ULg; Pétré, Benoît ULg; Husson, Eddy ULg et al

Poster (2017, August)

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See detailla qualité des sols, un capital
Carnol, Monique ULg; Krüger, Inken ULg; Malchair, Sandrine ULg et al

in Le grand livre de la Forêt 2017 (2017)

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See detailJoints in building structures subjected to exceptional events
Demonceau, Jean-François ULg; Jaspart, Jean-Pierre ULg

in Stahlbau, holzbau und Verbundbau - Festschrift zum 60. Geburtstag von Uni.-Prof. Dr.-Ing. Ulrike Kuhlmann (2017)

In this paper, recent developments aiming at characterising the behaviour of joints met in building structures subjected to exceptional events will be summarised. Section 2 gives an overview of the ... [more ▼]

In this paper, recent developments aiming at characterising the behaviour of joints met in building structures subjected to exceptional events will be summarised. Section 2 gives an overview of the investigations conducted on joints subjected to combined bending moments and axial loads. The behaviour of joints subjected to elevated temperatures associated to some specific exceptional events is then addressed in Section 3. Finally, the development of strain rate effects in joint components when subjected to dynamic actions is considered in Section 4. [less ▲]

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See detailSimilarity of the Jovian satellite footprints: spots multiplicity and dynamics
Bonfond, Bertrand ULg; Grodent, Denis ULg; Badman, S. V. et al

in Icarus (2017), 292(2017), 208217

In the magnetospheres of Jupiter and Saturn, the intense interaction of the satellites Io, Europa, Ganymede and Enceladus with their surrounding plasma environment leaves a signature in the aurora of the ... [more ▼]

In the magnetospheres of Jupiter and Saturn, the intense interaction of the satellites Io, Europa, Ganymede and Enceladus with their surrounding plasma environment leaves a signature in the aurora of the planet. Called satellite footprints, these auroral features appear either as a single spot (Europa and Enceladus) or as multiple spots (Io and Ganymede). Moreover, they can be followed by extended trailing tails in the case of Io and Europa, while no tail has been reported for Ganymede and Enceladus, yet. Here we show that all Jovian footprints can be made of several spots. Furthermore, the footprints all experience brightness variations on timescale of 2-3 minutes. We also demonstrate that the satellite location relative to the plasma sheet is not the only driver for the footprint brightness, but that the plasma environment and the magnetic field strength also play a role. These new findings demonstrate that the Europa and Ganymede footprints are very similar to the Io footprint. As a consequence, the processes expected to take place at Io, such as the bi-directional electron acceleration by Alfvén waves or the partial reflection of these waves on plasma density gradients, can most likely be extended to the other footprints, suggesting that they are indeed universal processes. [less ▲]

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See detailInfluence of urban patterns on flooding
Bruwier, Martin ULg; Mustafa, Ahmed; Aliaga, Daniel et al

in E-proceedings of the 37th IAHR World Congress (2017, August)

The goal of this paper is to identify the respective influence of different characteristics of urban patterns on urban flooding. A set of 2,290 alternate urban patterns was generated randomly using an ... [more ▼]

The goal of this paper is to identify the respective influence of different characteristics of urban patterns on urban flooding. A set of 2,290 alternate urban patterns was generated randomly using an urban generator tool providing the geometry of buildings and their relative location to the ground, over a square area of 1 km². Steady 2-D hydraulic computations were performed for these 2,290 different urban patterns with identical hydraulic boundary conditions. The computational time was reduced by using an anisotropic porosity model. This model uses relatively coarse computational cells; but preserves information from the detailed topographic data through the use of porosity parameters. Based on the computed maps of waterdepths for the 2,290 urban patterns, a sensitivity analysis based on a multiple linear regression was performed to outline the most influential urban characteristics. [less ▲]

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See detailVoice use among music theory teachers
Schiller, Isabel ULg; Morsomme, Dominique ULg; Sfez, Lou et al

Conference (2017, August)

In Belgium, there is a particular group of music teachers referred to as music theory teachers. Working at music schools, they convey theoretical knowledge and practical musical skills to groups of ... [more ▼]

In Belgium, there is a particular group of music teachers referred to as music theory teachers. Working at music schools, they convey theoretical knowledge and practical musical skills to groups of individuals who learn music during their free-time. Even though music theory teachers use both speaking and singing voice intensively at work, little is known about their voice use profiles. This study investigated the vocal loading among French-speaking music theory teachers. Objectives were (1) to describe their professional and extra-professional vocal loading, (2) to determine the relationship between vocal loading and background noise level and (3) to investigate whether objectively measured vocal loading is reflected in music theory teachers’ auto-evaluation of their voice. Using voice dosimetry, 13 music theory teachers were monitored for one workweek. Parameters analysed were F0, voice sound pressure level (SPL), phonation time, vocal loading index (VLI) and background noise SPL. At the end of each monitoring day, subjects self-assessed their voice use by means of visual analogue scales. Results revealed (1) significantly higher vocal loading in the professional context than in the extra-professional context, (2) significant positive correlations between background noise level and the parameters F0, voice SPL and phonation time and (3) significant correlations between the VLI and auto-evaluation data (e.g. voice quality and vocal fatigue). These results highlight that teaching music theory is a profession with high vocal demands. At work, music theory teachers are exposed to high background noise, which seems to influence their voice use and may potentially contribute to the development of voice problems among this population. Visual analogue scales provide a promising tool to subjectively investigate vocal loading among music theory teachers. [less ▲]

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See detailLEARNING CHEMICAL KINETICS AT SECONDARY SCHOOL LEVEL: MISCONCEPTIONS AND ALTERNATIVE APPROACH
Karous, Hamad ULg; Nihant, Brigitte ULg; Leyh, Bernard ULg

Conference (2017, August)

Chemical kinetics occupies a central position in describing and understanding the dynamic behaviour of matter. It is then expected that this topic shares a significant part in the teaching curricula ... [more ▼]

Chemical kinetics occupies a central position in describing and understanding the dynamic behaviour of matter. It is then expected that this topic shares a significant part in the teaching curricula. Nevertheless, the review of the scarce literature on the topic reveals that little is usually invested to adequately include this field in the major programs. Most studies demonstrate that the teaching approaches in chemical kinetics often remain limited to the qualitative macroscopic description and do not identify the necessary relevant links between the macroscopic and the submicroscopic scales. Consequently, low levels of conceptual understanding and many misconceptions can be identified at the students’ level. Based on the constructivist approach in which the learners build their own cognitive structure, a new teaching sequence including qualitative and quantitative aspects of chemical kinetics for secondary school students (15-17 years old) is proposed. This teaching sequence allows the students to develop an ability to use corpuscular models as explanatory tools as well as an adequate conceptual understanding of chemical kinetics. This approach integrates visualization tools along with active learning strategies using, e.g., interactive websites. [less ▲]

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See detailCharacterising Industrial Sites' Flexibility with Reservoir Models
Cuvelier, Thibaut ULg

Poster (2017, August)

Electro-intensive industrial sites are very dependent on electricity prices to remain competitive. Nevertheless, they can often tune their processes in order to decrease their electricity consumption ... [more ▼]

Electro-intensive industrial sites are very dependent on electricity prices to remain competitive. Nevertheless, they can often tune their processes in order to decrease their electricity consumption during the most critical periods, for example by using decision support systems based on mathematical modelling of their processes. Our goal is to estimate the flexibility potential of a complete site, not to tune each process very precisely. To this end, we propose a generic paradigm to help conceiving such models: reservoirs are the basic building block, which allows for great expressiveness while being close to the physics. More specifically, we do not need very precise models for our purposes, but ones that can be efficiently included in optimisation models. Our first results show that the obtained reservoir models can give sufficiently good approximations for metallurgical and other processes. [less ▲]

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See detailEarly eukaryotes: insights from microanalyses of proterozoic microfossils
Cornet, Yohan ULg; Beghin, Jérémie ULg; Kabamba Baludikay, Blaise ULg et al

in Goldschmidt Abstracts, 2017 (2017, August)

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See detailPhysical modeling of overtopping induced fluvial dike failure: effects of the channel flow and floodplain innundation
Rifai, Ismail; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

Conference (2017, August)

Fluvial dikes have been constructed as flood defense structures, but their failure may lead to casualties and major damages in the protected areas. Flow overtopping is listed as the main cause of dike ... [more ▼]

Fluvial dikes have been constructed as flood defense structures, but their failure may lead to casualties and major damages in the protected areas. Flow overtopping is listed as the main cause of dike failure. An accurate assessment of the breach evolution is a prerequisite to a sound flood risk assessment and management. in contrast, the current knowledge of the physical processes involved in fluvial dike failure by overtopping remains highly fragmented. This paper presents experimental tests on the breaching of homogenous sand-dikes in a fluvial configuration, i.e. the flow is parallel to the longitudinal dike axis. Overtopping is initiated over a pilot notch at the dike crest. Experiments are performed for different inflow discharges in the main channel and under different levels of floodplain confinement. The transient evolution of the dike geometry is monitored using a laser profilometry technique. The detailed reconstruction of the breach formation and expansion provides key insights into the mechanisms involved in the failure of fluvial dikes. Results show that the breach development differs highly from experiments disregarding the flow parallel to the dike axis (i.e. frontal configuration) as in the fluvial configuration the breach develops mainly in the flow direction and the floodplain water level strongly conditions the breach horizontal and vertical extent. [less ▲]

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See detailAn efficient algorithm to decide periodicity of b-recognisable sets using MSDF convention
Boigelot, Bernard ULg; Mainz, Isabelle ULg; Marsault, Victor ULg et al

in Leibniz International Proceedings in Informatics (2017, August), 80

Given an integer base b>1, a set of integers is represented in base b by a language over {0,1,...,b-1}. The set is said to be b-recognisable if its representation is a regular language. It is known that ... [more ▼]

Given an integer base b>1, a set of integers is represented in base b by a language over {0,1,...,b-1}. The set is said to be b-recognisable if its representation is a regular language. It is known that eventually periodic sets are b-recognisable in every base b, and Cobham's theorem implies the converse: no other set is b-recognisable in every base b. We are interested in deciding whether a $b$-recognisable set of integers (given as a finite automaton) is eventually periodic. Honkala showed that this problem is decidable in 1986 and recent developments give efficient decision algorithms. However, they only work when the integers are written with the least significant digit first. In this work, we consider the natural order of digits (Most Significant Digit First) and give a quasi-linear algorithm to solve the problem in this case. [less ▲]

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See detailAs teorias semióticas face à fotografia
Dondero, Maria Giulia ULg

in Calavari, Suzi; Rodrigues, Angelica; Rocha, Nildicéia (Eds.) Proceedings VI SELIN – NOVAS PRÁTICAS EM PESQUISA SOBRE A LINGUAGEM: ROMPENDO FRONTEIRAS (2017, August)

Dans ce texte, je me propose de revenir sur les travaux en sémiotique qui ont marqué les études du champ interdisciplinaire de la photographie et de les poursuivre; l’objectif principal est de fournir ... [more ▼]

Dans ce texte, je me propose de revenir sur les travaux en sémiotique qui ont marqué les études du champ interdisciplinaire de la photographie et de les poursuivre; l’objectif principal est de fournir quelques pistes pour étudier, d’un point de vue sémiotique, l’image photographique en tant qu’objet pris dans des pratiques d’usage et d’interprétation diversifiées au sein des statuts sociaux de l’art, de la science, de la religion. [less ▲]

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See detailNETPerfTrace – Predicting Internet Path Dynamics and Performance with Machine Learning
Wassermann, Sarah ULg; Casas, Pedro; Cuvelier, Thibaut ULg et al

in Proceedings of Big-DAMA ’17 (2017, August)

We study the problem of predicting Internet path changes and path performance using traceroute measurements and machine learning models. Path changes are frequently linked to path inflation and ... [more ▼]

We study the problem of predicting Internet path changes and path performance using traceroute measurements and machine learning models. Path changes are frequently linked to path inflation and performance degradation, therefore the relevance of the problem. We introduce NETPerfTrace, an Internet Path Tracking system to forecast path changes and path latency variations. By relying on decision trees and using empirical distribution-based input features, we show that NETPerfTrace can predict (i) the remaining life time of a path before it actually changes and (ii) the number of path changes in a certain time period with relatively high accuracy. Through extensive evaluation, we demonstrate that NETPerfTrace highly outperforms DTRACK, a previous system with the same prediction targets. NETPerfTrace also offers path performance forecasting capabilities. In particular, our tool can predict path latency metrics, providing a system which can not only predict path changes, but also forecast their impact in terms of performance variations. We release NETPerfTrace as open software to the networking community, as well as all evaluation datasets. [less ▲]

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See detailRegiospecific radiolabelling of Nanofitin on Ni Magnetic Beads with [18F]FBEM and in vivo PET studies
Dammicco, Sylvestre ULg; Goux, Marine; Lemaire, Christian ULg et al

in Nuclear Medicine & Biology (2017)

Introduction: Nanofitins are low molecular weight, single chain and cysteine-free protein scaffolds able to selectively bind a defined biological target. They derive from Sac7d bacterial protein family ... [more ▼]

Introduction: Nanofitins are low molecular weight, single chain and cysteine-free protein scaffolds able to selectively bind a defined biological target. They derive from Sac7d bacterial protein family and are highly stable over a wide range of pH (0-13) and temperature (Tm ~80°C). Their extreme stability, low cost of production and high tolerability for chemical coupling make Nanofitins a very interesting alternative to antibodies and their fragments. Here, a hexahistidine tagged model Nanofitin (H4) directed against hen egg white lysozyme was radiolabelled and injected in mice to provide a baseline biodistribution and pharmacokinetic profiles to support future Nanofitin development programs. Method: A single cysteine residue has been genetically inserted in a model Nanofitin and its regioselective radiolabelling has been performed with 4-[18F]fluorobenzamido-N-ethylamino-maleimide ([18F]FBEM). The synthesis of [18F]FBEM has been completely implemented on a radiosynthesis unit (FastLab) including HPLC purification and formulation. Coupling with the [18F]FBEM has been achieved on a solid support (Ni magnetic beads) allowing rapid purification at room temperature without organic solvent. PET-MRI studies on C57BL/6 mice were conducted after injection of [18F]FBEM-Cys-H4 in order to access the biodistribution of this Nanofitin model. Results: Radiochemical yield (decay corrected) of 54±7% (n=4) was obtained after optimization for coupling the [18F]FBEM to Nanofitin. Pharmacokinetics results of [18F]FBEM-Cys-H4 revealed a fast clearance through the liver and the kidneys. Conclusion: An efficient new method on Ni magnetic beads was developed to radiolabelled his-tagged biomolecules with [18F]FBEM. This procedure was applied on a Nanofitin model Cys-H4 and biodistribution kinetic studies were achieved to evaluate the potential use of Nanofitin for diagnostic imaging. Fast clearance indicates that Nanofitins represent very interesting tools for diagnostic imaging. [less ▲]

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