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See detailThe Far Ultra-Violet Imager on the Icon Mission
Mende, Stephen; Frey, Harald; Rider, Kodi et al

in Space Science Reviews (2017)

ICON Far UltraViolet (FUV) imager contributes to the ICON science objectives by providing remote sensing measurements of the daytime and nighttime atmosphere/ ionosphere. During sunlit atmospheric ... [more ▼]

ICON Far UltraViolet (FUV) imager contributes to the ICON science objectives by providing remote sensing measurements of the daytime and nighttime atmosphere/ ionosphere. During sunlit atmospheric conditions, ICON FUV images the limb altitude profile in the shortwave (SW) band at 135.6 nm and the longwave (LW) band at 157 nm perpendicular to the satellite motion to retrieve the atmospheric O/N2 ratio. In conditions of atmospheric darkness, ICON FUV measures the 135.6 nm recombination emission of O+ ions used to compute the nighttime ionospheric altitude distribution. ICON Far Ultra- Violet (FUV) imager is a Czerny–Turner design Spectrographic Imager with two exit slits and corresponding back imager cameras that produce two independent images in separate wavelength bands on two detectors. All observations will be processed as limb altitude profiles. In addition, the ionospheric 135.6 nm data will be processed as longitude and latitude spatial maps to obtain images of ion distributions around regions of equatorial spread F. The ICON FUV optic axis is pointed 20 degrees below local horizontal and has a steering mirror that allows the field of view to be steered up to 30 degrees forward and aft, to keep the local magnetic meridian in the field of view. The detectors are micro channel plate (MCP) intensified FUV tubes with the phosphor fiber-optically coupled to Charge Coupled Devices (CCDs). The dual stack MCP-s amplify the photoelectron signals to overcome the CCD noise and the rapidly scanned frames are co-added to digitally create 12-second integrated images. Digital on-board signal processing is used to compensate for geometric distortion and satellite motion and to achieve data compression. The instrument was originally aligned in visible light by using a special grating and visible cameras. Final alignment, functional and environmental testing and calibration were performed in a large vacuum chamber with a UV source. The test and calibration program showed that ICON FUV meets its design requirements and is ready to be launched on the ICON spacecraft. [less ▲]

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See detailThe EBLM project. III. A Saturn-size low-mass star at the hydrogen-burning limit
von Boetticher, Alexander; Triaud, Amaury H. M. J.; Queloz, Didier et al

in Astronomy and Astrophysics (2017), 604

We report the discovery of an eclipsing binary system with mass-ratio q ˜ 0.07. After identifying a periodic photometric signal received by WASP, we obtained CORALIE spectroscopic radial velocities and ... [more ▼]

We report the discovery of an eclipsing binary system with mass-ratio q ˜ 0.07. After identifying a periodic photometric signal received by WASP, we obtained CORALIE spectroscopic radial velocities and follow-up light curves with the Euler and TRAPPIST telescopes. From a joint fit of these data we determine that EBLM J0555-57 consists of a sun-like primary star that is eclipsed by a low-mass companion, on a weakly eccentric 7.8-day orbit. Using a mass estimate for the primary star derived from stellar models, we determine a companion mass of 85 ± 4 M[SUB]Jup[/SUB] (0.081 M[SUB]⊙[/SUB]) and a radius of 0.84[SUP]+ 0.14[/SUP][SUB]-0.04[/SUB]R[SUB]Jup[/SUB] (0.084 R[SUB]⊙[/SUB]) that is comparable to that of Saturn. EBLM J0555-57Ab has a surface gravity log g[SUB]2[/SUB] =5.50[SUP]+ 0.03[/SUP][SUB]-0.13[/SUB] and is one of the densest non-stellar-remnant objects currently known. These measurements are consistent with models of low-mass stars. The photometry tables and radial velocities are only available at the CDS and on demand via anonymous ftp to <A href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A> (<A href="http://130.79.128.5">http://130.79.128.5</A>) or via <A href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/604/L6">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/604/L6</A> [less ▲]

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See detailRegularized Discriminant Analysis in Presence of Cellwise Contamination
Aerts, Stéphanie ULiege; Wilms, Ines

Conference (2017, August 01)

Quadratic and Linear Discriminant Analysis (QDA/LDA) are the most often applied classification rules under normality. In QDA, a separate covariance matrix is estimated for each group. If there are more ... [more ▼]

Quadratic and Linear Discriminant Analysis (QDA/LDA) are the most often applied classification rules under normality. In QDA, a separate covariance matrix is estimated for each group. If there are more variables than observations in the groups, the usual estimates are singular and cannot be used anymore. Assuming homoscedasticity, as in LDA, reduces the number of parameters to estimate. This rather strong assumption is however rarely verified in practice. Regularized discriminant techniques that are computable in high-dimension and cover the path between the two extremes QDA and LDA have been proposed in the literature. However, these procedures rely on sample covariance matrices. As such, they become inappropriate in presence of cellwise outliers, a type of outliers that is very likely to occur in high-dimensional datasets. We propose cellwise robust counterparts of these regularized discriminant techniques by inserting cellwise robust covariance matrices. Our methodology results in a family of discriminant methods that are robust against outlying cells, cover the gap between LDA and QDA and are computable in high-dimension. [less ▲]

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See detailImpact of dependency on the distribution of p-value
Ernst, Marie ULiege; Swan, Yvik ULiege

Conference (2017, August 01)

We study the impact of dependence assumptions on the distribution of p-values and quantiles for repeated testing on dependent data. This leads us to considering the general problem of the quality of a ... [more ▼]

We study the impact of dependence assumptions on the distribution of p-values and quantiles for repeated testing on dependent data. This leads us to considering the general problem of the quality of a binomial approximation to the distribution of a sum of dependent indicator variables. Whenever possible we use classical and adhoc versions of Stein’s method to provide tight bounds on classical probability distances. In many cases, however, the relevant expressions are intractable and we resort to empirical analysis by extensive simulations. We apply our findings to a realistic real-life scenario. [less ▲]

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See detailThe quest for magnetic massive stars in the Magellanic Clouds
Nazé, Yaël ULiege; Bagnulo, S.; Walborn, N. R. et al

in The Lives and Death-Throes of Massive Stars (2017, August 01)

The Of?p category was introduced more than 40 years ago to gather several Galactic stars with some odd properties. Since 2000, spectropolarimetry, high-resolution spectroscopy, long-term photometry, and X ... [more ▼]

The Of?p category was introduced more than 40 years ago to gather several Galactic stars with some odd properties. Since 2000, spectropolarimetry, high-resolution spectroscopy, long-term photometry, and X-ray observations have revealed their nature: magnetic oblique rotators - they all have magnetic fields that confine their winds. Several Of?p stars have now been detected in the Magellanic Clouds, likely the prototypes of magnetic massive stars at low metallicity. This contribution will present the most recent photometric, spectroscopic, and spectropolarimetric data, along with the first modeling of these objects. [less ▲]

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See detailMolecular Tools for the Detection and Quantification of Toxigenic Cyanobacteria
Kurmayer, Rainer; Sivonen, Kaarina; Wilmotte, Annick ULiege et al

Book published by John Wiley and sons LTD - This edition first published 2017 (2017)

A guide to state-of-the-art molecular tools for monitoring and managing the toxigenicity of cyanobacteria Runaway climate change has made the monitoring and management of toxigenic organisms in the ... [more ▼]

A guide to state-of-the-art molecular tools for monitoring and managing the toxigenicity of cyanobacteria Runaway climate change has made the monitoring and management of toxigenic organisms in the world’s bodies of water more urgent than ever. In order to influence public policy regarding the detection and quantification of those organisms, it is incumbent upon scientists to clearly demonstrate to policy makers the increase of toxigenic cyanobacteria and the threats they pose. As molecular methods can handle many samples in short time, they are the most reliable, cost-effective tools currently available for tracking cyanotoxicity worldwide. This volume arms scientists with the tools they need to track toxigenicity in surface waters and food supplies and, hopefully, to develop new techniques for managing the spread of toxic cyanobacteria. This book offers the first comprehensive treatment of molecular tools for monitoring cyanotoxicity. Growing out of the findings of the landmark European Cooperation in Science and Technology Cyanobacteria project (CYANOCOST), it provides detailed, practical coverage of the full array of available molecular tools and protocols, from water sampling, nucleic acid extraction, and downstream analysis—including PCR and qPCR based methods—to genotyping (DGGE), diagnostic microarrays, and community characterization using next-gen sequencing techniques. [less ▲]

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See detailBioinformatic Processing of Amplicon Sequencing Datasets
Sweetlove, Maxime; Obbels, Dagmar; Verleyen, Elie et al

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

Amplicon sequencing can be a very powerful approach for detecting toxic cyanobacteria or any other kind of microorganism during monitoring programs. However, owing to the huge size of next-generation ... [more ▼]

Amplicon sequencing can be a very powerful approach for detecting toxic cyanobacteria or any other kind of microorganism during monitoring programs. However, owing to the huge size of next-generation sequencing (NGS) datasets (up to several Gb), there is an obvious need for semi-automatic data processing and statistical analysis, as well as visualization of the patterns found. Importantly, raw NGS data contain errors, some of which are easily detected (e.g. too short or low-quality reads), while others remain hidden even after the most stringent quality controls (e.g. chimeras, contaminations, reads with large insertions or deletions, referred to as “indels”). As a consequence, NGS data need to be interpreted with caution, and bioinformatics analysis implementing poor error identification can easily lead to erroneous conclusions. Hence, a crucial step in the analysis of NGS data is the detection and removal of as many erroneous reads as possible. Moreover, bioinformatics involve additional preprocessing steps, including demultiplexing (i.e. grouping reads to samples according to the barcode sequence), deleting non-biological tags together with the adaptors and primer sequences, and removing chimeric sequences. In addition, the bioinformatics pipelines enable the quality-filtered sequences to be clustered into biologically relevant operational taxonomic units (OTUs), which form the basis of the statistical analysis, including the calculation of alpha- and beta-diversity. [less ▲]

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See detailTaxonomic Identification of Cyanobacteria by a Polyphasic Approach
Wilmotte, Annick ULiege; Laughinghouse, Dail Haywood IV; Capelli, Camilla et al

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

In this chapter, we shall discuss the criteria and methods to be adopted for the taxonomic identification and classification of cyanobacteria. This includes a brief introduction of the two Codes of ... [more ▼]

In this chapter, we shall discuss the criteria and methods to be adopted for the taxonomic identification and classification of cyanobacteria. This includes a brief introduction of the two Codes of Nomenclature ruling in parallel on the valid naming of these organisms. We shall then present the major steps important for cyanobacterial taxa identification and their nomenclature. These include: 1) determination of morphology by light microscopy; 2) genetic characterization by single and/or multilocus sequence typing; 3) the assignment of the organism to a taxonomic entity (genus, species, eco- and/or genotype within a species) by reference to, and phylogenetic analysis of, cyanobacterial nucleotide sequences available in public repositories. Ideally, these methods should be accompanied by the determination of other relevant properties (ultrastructural, physiological, biochemical, and ecological characteristics) that may help to define/redefine and circumscribe the cyanobacterial taxon under study. [less ▲]

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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 ULiege; Crama, Yves ULiege; 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 ULiege

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 ULiege

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 detailCorrigendum: Temporality of Features in Near-Death Experience Narratives
Martial, Charlotte ULiege; Cassol, Helena ULiege; Antonopoulos, Georgios ULiege et al

in Frontiers in Human Neuroscience (2017)

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

Poster (2017, August)

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See detailla qualité des sols, un capital
Carnol, Monique ULiege; Krüger, Inken ULiege; Malchair, Sandrine ULiege 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 ULiege; Jaspart, Jean-Pierre ULiege

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 ULiege; Grodent, Denis ULiege; 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 ULiege; 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 ULiege; Morsomme, Dominique ULiege; 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 ULiege; Nihant, Brigitte ULiege; Leyh, Bernard ULiege

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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