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See detailRealization of the Najafi-Golestanian microswimmer
Grosjean, Galien ULg; Hubert, Maxime ULg; Lagubeau, Guillaume et al

in Physical Review. E : Statistical, Nonlinear, and Soft Matter Physics (2016), 94(2), 021101

A paradigmatic microswimmer is the three-linked-spheres model, which follows a minimalist approach for propulsion by shape shifting. As such, it has been the subject of numerous analytical and numerical ... [more ▼]

A paradigmatic microswimmer is the three-linked-spheres model, which follows a minimalist approach for propulsion by shape shifting. As such, it has been the subject of numerous analytical and numerical studies. In this Rapid Communication, an experimental three-linked-spheres swimmer is created by self-assembling ferromagnetic particles at an air-water interface. It is powered by a uniform oscillating magnetic field. A model, using two harmonic oscillators, reproduces the experimental findings. Because the model remains general, the same approach could be used to design a variety of efficient microswimmers. [less ▲]

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See detailLOTUS: a low-cost, ultraviolet spectrograph
Steele, I. A.; Marchant, J. M.; Jermak, H. E. et al

in Monthly Notices of the Royal Astronomical Society (2016), 460

We describe the design, construction and commissioning of a simple, low-cost long-slit spectrograph for the Liverpool Telescope. The design is optimized for near-UV and visible wavelengths and uses all ... [more ▼]

We describe the design, construction and commissioning of a simple, low-cost long-slit spectrograph for the Liverpool Telescope. The design is optimized for near-UV and visible wavelengths and uses all transmitting optics. It exploits the instrument focal plane field curvature to partially correct axial chromatic aberration. A stepped slit provides narrow (2.5 × 95 arcsec) and wide (5 × 25 arcsec) options that are optimized for spectral resolution and flux calibration, respectively. On sky testing shows a wavelength range of 3200-6300 Å with a peak system throughput (including detector quantum efficiency) of 15 per cent and wavelength dependent spectral resolution of R = 225-430. By repeated observations of the symbiotic emission line star AG Peg, we demonstrate the wavelength stability of the system is <2 Å rms and is limited by the positioning of the object in the slit. The spectrograph is now in routine operation monitoring the activity of comet 67P/Churyumov-Gerasimenko during its current post-perihelion apparition. [less ▲]

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See detailThe 19 Feb. 2016 Outburst of Comet 67P/CG: An ESA Rosetta Multi-Instrument Study
Grün, E.; Agarwal, J.; Altobelli, N. et al

in Monthly Notices of the Royal Astronomical Society (2016)

On 19 Feb. 2016 nine Rosetta instruments serendipitously observed an outburst of gas and dust from the nucleus of comet 67P/Churyumov-Gerasimenko. Among these instruments were cameras and spectrometers ... [more ▼]

On 19 Feb. 2016 nine Rosetta instruments serendipitously observed an outburst of gas and dust from the nucleus of comet 67P/Churyumov-Gerasimenko. Among these instruments were cameras and spectrometers ranging from UV over visible to microwave wavelengths, in-situ gas, dust and plasma instruments, and one dust collector. At 9:40 a dust cloud developed at the edge of an image in the shadowed region of the nucleus. Over the next two hours the instruments recorded a signature of the outburst that significantly exceeded the background. The enhancement ranged from 50% of the neutral gas density at Rosetta to factors >100 of the brightness of the coma near the nucleus. Dust related phenomena (dust counts or brightness due to illuminated dust) showed the strongest enhancements (factors >10). However, even the electron density at Rosetta increased by a factor 3 and consequently the spacecraft potential changed from ˜-16 V to -20 V during the outburst. A clear sequence of events was observed at the distance of Rosetta (34 km from the nucleus): within 15 minutes the Star Tracker camera detected fast particles (˜25 m s[SUP]-1[/SUP]) while 100 μm radius particles were detected by the GIADA dust instrument ˜1 hour later at a speed of ~6 m s[SUP]-1[/SUP]. The slowest were individual mm to cm sized grains observed by the OSIRIS cameras. Although the outburst originated just outside the FOV of the instruments, the source region and the magnitude of the outburst could be determined. [less ▲]

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See detail2D-photochemical model for forbidden oxygen line emission for comet 1P/Halley
Cessateur, G.; De Keyser, J.; Maggiolo, R. et al

in Monthly Notices of the Royal Astronomical Society (2016)

We present here a 2D-model of photochemistry for computing the production and loss mechanisms of the O([SUP]1[/SUP]S) and O([SUP]1[/SUP]D) states, which are responsible for the emission lines at 577.7 nm ... [more ▼]

We present here a 2D-model of photochemistry for computing the production and loss mechanisms of the O([SUP]1[/SUP]S) and O([SUP]1[/SUP]D) states, which are responsible for the emission lines at 577.7 nm, 630 nm, and 636.4 nm, in case of the comet 1P/Halley. The presence of O[SUB]2[/SUB] within cometary atmospheres, measured by the in-situ ROSETTA and GIOTTO missions, necessitates a revision of the usual photochemical models. Indeed, the photodissociation of molecular oxygen also leads to a significant production of oxygen in excited electronic states. In order to correctly model the solar UV flux absorption, we consider here a 2D configuration. While the green to red-doublet ratio is not affected by the solar UV flux absorption, estimates of the red-doublet and green lines emissions are, however, overestimated by a factor of two in the 1D model compared to the 2D model. Considering a spherical symmetry, emission maps can be deduced from the 2D model in order to be directly compared to ground and/or in-situ observations. [less ▲]

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See detailThe Athena X-ray Integral Field Unit (X-IFU)
Barret, Didier; Trong, Thien Lam; den Herder, Jan-Willem et al

in Proc. SPIE. 9905, Space Telescopes and Instrumentation 2016: Ultraviolet to Gamma Ray, 99052F. (August 17, 2016) (2016, August 01)

The X-ray Integral Field Unit (X-IFU) on board the Advanced Telescope for High-ENergy Astrophysics (Athena) will provide spatially resolved high-resolution X-ray spectroscopy from 0.2 to 12 keV, with 5 ... [more ▼]

The X-ray Integral Field Unit (X-IFU) on board the Advanced Telescope for High-ENergy Astrophysics (Athena) will provide spatially resolved high-resolution X-ray spectroscopy from 0.2 to 12 keV, with 5 arc second pixels over a field of view of 5 arc minute equivalent diameter and a spectral resolution of 2.5 eV up to 7 keV. In this paper, we first review the core scientific objectives of Athena, driving the main performance parameters of the X-IFU, namely the spectral resolution, the field of view, the effective area, the count rate capabilities, the instrumental background. We also illustrate the breakthrough potential of the X-IFU for some observatory science goals. Then we briefly describe the X-IFU design as defined at the time of the mission consolidation review concluded in May 2016, and report on its predicted performance. Finally, we discuss some options to improve the instrument performance while not increasing its complexity and resource demands (e.g. count rate capability, spectral resolution). The X-IFU will be provided by an international consortium led by France, The Netherlands and Italy, with further ESA member state contributions from Belgium, Finland, Germany, Poland, Spain, Switzerland and two international partners from the United States and Japan. [less ▲]

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See detailHubert Pierlot : Pages d'histoire
Pierlot, Hubert; Behrendt, Christian ULg

Report (2016)

Entre le 5 juillet et le 19 juillet 1947, l’ancien Premier ministre et chef du gouvernement en exil à Londres Hubert PIERLOT publie une série de dissertations, sous le nom de « Pages d’Histoire », dans le ... [more ▼]

Entre le 5 juillet et le 19 juillet 1947, l’ancien Premier ministre et chef du gouvernement en exil à Londres Hubert PIERLOT publie une série de dissertations, sous le nom de « Pages d’Histoire », dans le quotidien Le Soir. Elles traitent en détail, procédant à une « analyse étayée et argumentée », de la Commission d’information de 1946 instituée par le Roi LEOPOLD III, de l’épisode de Maasmechelen (Mechelen-sur-Meuse), ainsi que de la campagne des dix-huit jours, pour ne citer que ces évènements, et s’appuient essentiellement sur l’exposé, les Carnets personnels et le rapport de la Commission d’information de 1947. Largement inaccessibles et absentes de nombreuses bibliothèques universitaires, dont de celle de l'Université de Liège, le Service de Droit constitutionnel de l'Université de Liège les rend, dans un but de recherche scientifique, accessibles ici. Document exclusivement à portée académique ; reproduction interdite. [less ▲]

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See detailEnabling the direct detection of earth-sized exoplanets with the LBTI HOSTS project: a progress report
Danchi, W.; Bailey, V.; Bryden, G. et al

in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series (2016, August 01)

NASA has funded a project called the Hunt for Observable Signatures of Terrestrial Systems (HOSTS) to survey nearby solar type stars to determine the amount of warm zodiacal dust in their habitable zones ... [more ▼]

NASA has funded a project called the Hunt for Observable Signatures of Terrestrial Systems (HOSTS) to survey nearby solar type stars to determine the amount of warm zodiacal dust in their habitable zones. The goal is not only to determine the luminosity distribution function but also to know which individual stars have the least amount of zodiacal dust. It is important to have this information for future missions that directly image exoplanets as this dust is the main source of astrophysical noise for them. The HOSTS project utilizes the Large Binocular Telescope Interferometer (LBTI), which consists of two 8.4-m apertures separated by a 14.4-m baseline on Mt. Graham, Arizona. The LBTI operates in a nulling mode in the mid-infrared spectral window (8-13 μm), in which light from the two telescopes is coherently combined with a 180 degree phase shift between them, producing a dark fringe at the location of the target star. In doing so the starlight is greatly reduced, increasing the contrast, analogous to a coronagraph operating at shorter wavelengths. The LBTI is a unique instrument, having only three warm reflections before the starlight reaches cold mirrors, giving it the best photometric sensitivity of any interferometer operating in the mid-infrared. It also has a superb Adaptive Optics (AO) system giving it Strehl ratios greater than 98% at 10 μm. In 2014 into early 2015 LBTI was undergoing commissioning. The HOSTS project team passed its Operational Readiness Review (ORR) in April 2015. The team recently published papers on the target sample, modeling of the nulled disk images, and initial results such as the detection of warm dust around η Corvi. Recently a paper was published on the data pipeline and on-sky performance. An additional paper is in preparation on β Leo. We will discuss the scientific and programmatic context for the LBTI project, and we will report recent progress, new results, and plans for the science verification phase that started in February 2016, and for the survey. [less ▲]

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See detailOverview of LBTI: a multipurpose facility for high spatial resolution observations
Hinz, P. M.; Defrere, Denis ULg; Skemer, A. et al

in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series (2016, August 01)

The Large Binocular Telescope Interferometer (LBTI) is a high spatial resolution instrument developed for coherent imaging and nulling interferometry using the 14.4 m baseline of the 2×8.4 m LBT. The ... [more ▼]

The Large Binocular Telescope Interferometer (LBTI) is a high spatial resolution instrument developed for coherent imaging and nulling interferometry using the 14.4 m baseline of the 2×8.4 m LBT. The unique telescope design, comprising of the dual apertures on a common elevation-azimuth mount, enables a broad use of observing modes. The full system is comprised of dual adaptive optics systems, a near-infrared phasing camera, a 1-5 μm camera (called LMIRCam), and an 8-13 μm camera (called NOMIC). The key program for LBTI is the Hunt for Observable Signatures of Terrestrial planetary Systems (HOSTS), a survey using nulling interferometry to constrain the typical brightness from exozodiacal dust around nearby stars. Additional observations focus on the detection and characterization of giant planets in the thermal infrared, high spatial resolution imaging of complex scenes such as Jupiter's moon, Io, planets forming in transition disks, and the structure of active Galactic Nuclei (AGN). Several instrumental upgrades are currently underway to improve and expand the capabilities of LBTI. These include: Improving the performance and limiting magnitude of the parallel adaptive optics systems; quadrupling the field of view of LMIRcam (increasing to 20"x20"); adding an integral field spectrometry mode; and implementing a new algorithm for path length correction that accounts for dispersion due to atmospheric water vapor. We present the current architecture and performance of LBTI, as well as an overview of the upgrades. [less ▲]

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See detailDetection of nitrogen stress on winter wheat by multispectral machine vision
Marlier, Guillaume ULg; Gritten, Fanny; Leemans, Vincent ULg et al

Conference (2016, August 01)

Hand-held sensors (SPAD meter, N-Tester, …) used for detecting the leaves nitrogen concentration (Nc) present several drawbacks. The nitrogen concentration is gained by an indirect way through the ... [more ▼]

Hand-held sensors (SPAD meter, N-Tester, …) used for detecting the leaves nitrogen concentration (Nc) present several drawbacks. The nitrogen concentration is gained by an indirect way through the chlorophyll concentration and the leaves have to be fixed in a defined position for the measurements. These drawbacks could be overcome by an imaging device that measures the canopy reflectance. Hence, the objective of the paper is to analyse the potential of multispectral imaging for detecting nitrogen concentration. The tests were carried out on parcels submitted to nitrogen inputs varying from 0 to 180 kg N.ha-1. Reference Nc measurements were obtained by the Kjeldahl method and a Hydro N-Tester (Yara). The developed imaging system comprised a CMOS camera and a set of 22 interference filters ranging from 450 to 950 nm mounted on a wheel steered by a stepper motor. The image acquisition and the motor rotation were controlled by a program written in C++. The crop was imaged vertically at one meter height. The raw images presented 1280×1024 pixels covering an area of approximately 0.25 m² and were recorded with a 12-bit luminance resolution. To deal with the natural irradiance variability of the scene, a white reference was used and the integration time was automatically adjusted for each image. The image treatment included the segmentation of Photosynthetically Active Leaves (PAL) by using Bayes theorem and the computation of the mean PAL reflectance after correction of background and illumination fluctuations. Nc was estimated on the basis of the 22 filters by the Partial Least Square (PLS) method and by four filters selected by the Best Subset Selection (BSS) method. In comparison with the Kjeldahl method, the estimation of Nc by means of the Hydro N-Tester, the PLS method and the BSS method (filters 600-80, 950-100, 650-40 and 450-80 nm) gave determination coefficients equal to 0.53, 0.63, and 0.62, respectively. This indicated that the full multi-spectral approach gave significantly better Nc estimation than a portable device and suggested that a camera equipped with four filters would give similar results. [less ▲]

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See detailWASP-86b and WASP-102b: super-dense versus bloated planets
Faedi, F.; Gómez Maqueo Chew, Y.; Pollacco, D. et al

E-print/Working paper (2016)

We report the discovery of two transiting planetary systems: a super dense, sub-Jupiter mass planet WASP-86b (\mpl\ = 0.82 $\pm$ 0.06 \mj, \rpl\ = 0.63 $\pm$ 0.01 \rj), and a bloated, Saturn-like planet ... [more ▼]

We report the discovery of two transiting planetary systems: a super dense, sub-Jupiter mass planet WASP-86b (\mpl\ = 0.82 $\pm$ 0.06 \mj, \rpl\ = 0.63 $\pm$ 0.01 \rj), and a bloated, Saturn-like planet WASP-102b (\mpl\ = 0.62 $\pm$ 0.04 \mj, \rpl\=1.27 $\pm$ 0.03 \rj). They orbit their host star every $\sim$5.03, and $\sim$2.71 days, respectively. The planet hosting WASP-86 is a F7 star (\teff\ = 6330$\pm$110 K, \feh\ = $+$0.23 $\pm$ 0.14 dex, and age $\sim$0.8--1~Gyr), WASP-102 is a G0 star (\teff\ = 5940$\pm$140 K, \feh\ = $-$0.09$\pm$ 0.19 dex, and age $\sim$1~Gyr). These two systems highlight the diversity of planetary radii over similar masses for giant planets with masses between Saturn and Jupiter. WASP-102b shows a larger than model-predicted radius, indicating that the planet is receiving a strong incident flux which contributes to the inflation of its radius. On the other hand, with a density of $\rho_{pl}$ = 3.24$\pm$~0.3~$\rho_{jup}$, WASP-86b is the densest gas giant planet among planets with masses in the range 0.05 $<M$_{pl}$<$ 2.0 \mj. With a stellar mass of 1.34 M$_{\odot}$ and \feh = $+$0.23 dex, WASP-86 could host additional massive and dense planets given that its protoplanetary disc is expected to also have been enriched with heavy elements. In order to match WASP-86b's density, an extrapolation of theoretical models predicts a planet composition of more than 80\% in heavy elements (whether confined in a core or mixed in the envelope). This fraction corresponds to a core mass of approximately 210\me\ for WASP-86b's mass of \mpl$\sim$260\,\me. Only planets with masses larger than about 2\mj\ have larger densities than that of WASP-86b, making it exceptional in its mass range. [less ▲]

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See detailEvidence of magnetic field decay in massive main-sequence stars
Fossati, L.; Schneider, F. R. N.; Castro, N. et al

in Astronomy and Astrophysics (2016), 592

A significant fraction of massive main-sequence stars show strong, large-scale magnetic fields. The origin of these fields, their lifetimes, and their role in shaping the characteristics and evolution of ... [more ▼]

A significant fraction of massive main-sequence stars show strong, large-scale magnetic fields. The origin of these fields, their lifetimes, and their role in shaping the characteristics and evolution of massive stars are currently not well understood. We compile a catalogue of 389 massive main-sequence stars, 61 of which are magnetic, and derive their fundamental parameters and ages. The two samples contain stars brighter than magnitude 9 in the V-band and range in mass between 5 and 100 M[SUB]⊙[/SUB]. We find that the fractional main-sequence age distribution of all considered stars follows what is expected for a magnitude limited sample, while that of magnetic stars shows a clear decrease towards the end of the main sequence. This dearth of old magnetic stars is independent of the choice of adopted stellar evolution tracks, and appears to become more prominent when considering only the most massive stars. We show that the decreasing trend in the distribution is significantly stronger than expected from magnetic flux conservation. We also find that binary rejuvenation and magnetic suppression of core convection are unlikely to be responsible for the observed lack of older magnetic massive stars, and conclude that its most probable cause is the decay of the magnetic field, over a time span longer than the stellar lifetime for the lowest considered masses, and shorter for the highest masses. We then investigate the spin-down ages of the slowly rotating magnetic massive stars and find them to exceed the stellar ages by far in many cases. The high fraction of very slowly rotating magnetic stars thus provides an independent argument for a decay of the magnetic fields. [less ▲]

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See detailThe Gaia-ESO Survey: pre-main-sequence stars in the young open cluster NGC 3293
Delgado, A. J.; Sampedro, L.; Alfaro, E. J. et al

in Monthly Notices of the Royal Astronomical Society (2016), 460

The young open cluster NGC3293 is included in the observing program of the Gaia-ESO survey (GES). The radial velocity values provided have been used to assign cluster membership probabilities by means of ... [more ▼]

The young open cluster NGC3293 is included in the observing program of the Gaia-ESO survey (GES). The radial velocity values provided have been used to assign cluster membership probabilities by means of a single-variable parametric analysis. These membership probabilities are compared to the results of the photometric membership assignment of NGC3293, based on UBVRI photometry. The agreement of the photometric and kinematic member samples amounts to 65 per cent, and could increase to 70 per cent as suggested by the analysis of the differences between both samples. A number of photometric PMS candidate members of spectral type F are found, which are confirmed by the results from VPHAS photometry and SED fitting for the stars in common with VPHAS and GES data sets. Excesses at mid- and near-infrared wavelengths, and signs of Hα emission, are investigated for them. Marginal presence of Hα emission or infilling is detected for the candidate members. Several of them exhibit moderate signs of U excess and weak excesses at mid-IR wavelengths. We suggest that these features originate from accretion discs in their last stages of evolution. [less ▲]

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See detailEnhancing Cover Song Identification with Hierarchical Rank Aggregation
Osmalsky, Julien ULg; Van Droogenbroeck, Marc ULg; Embrechts, Jean-Jacques ULg

in Proceedings of the 17th International for Music Information Retrieval Conference (2016, August)

Abstract Cover song identification involves calculating pairwise similarities between a query audio track and a database of reference tracks. While most authors make exclusively use of chroma features ... [more ▼]

Abstract Cover song identification involves calculating pairwise similarities between a query audio track and a database of reference tracks. While most authors make exclusively use of chroma features, recent work tends to demonstrate that combining similarity estimators based on multiple audio features increases the performance. We improve this approach by using a hierarchical rank aggregation method for combining estimators based on different features. More precisely, we first aggregate estimators based on global features such as the tempo, the duration, the loudness, the beats, and the average chroma vectors. Then, we aggregate the resulting composite estimator with four popular state-of-the-art methods based on chromas as well as timbre sequences. We further introduce a refinement step for the rank aggregation called “local Kemenization” and quantify its benefit for cover song identification. The performance of our method is evaluated on the Second Hand Song dataset. Our experiments show an significant improvement of the performance, up to an increase of more than 200 % of the number of queries identified in the Top-1, compared to previous results. [less ▲]

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See detailCalcium-Iron Oxide as Energy Storage Medium in Rechargeable Oxide Batteries
Berger, Cornelius M.; Mahmoud, Abdelfattah ULg; Hermann, Raphaël ULg et al

in Journal of the American Ceramic Society (2016)

Rechargeable oxide batteries (ROB) comprise a regenerative solid oxide cell (rSOC) and a storage medium for oxygen ions. A sealed ROB avoids pumping loss, heat loss, and gas purity expenses in comparison ... [more ▼]

Rechargeable oxide batteries (ROB) comprise a regenerative solid oxide cell (rSOC) and a storage medium for oxygen ions. A sealed ROB avoids pumping loss, heat loss, and gas purity expenses in comparison with conventional rSOC. However, the iron oxide base storage medium degrades during charging– discharging cycles. In comparison, CaFe3O5 has improved cyclability and a high reversible oxygen storage capacity of 22.3 mol%. In this study, we analyzed the redox mechanism of this compound. After a solid-state synthesis of CaFe3O5, we verified the phase composition and studied the redox reaction by means of X-ray diffraction, Mossbauer spectrometry, and scanning electron microscopy. Results show a great potential to operate the battery with this storage material during multiple charging–discharging cycles. [less ▲]

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See detailHabitat use of an unstudied Lepilemur in the northwest Madagascar: L. mittermeieri
Wilmet, Leslie ULg; Vermeulen, Cédric ULg; Beudels-Jamar et al

Conference (2016, August)

Biodiversity and endemism is very high in Madagascar and Genus Lepilemur is part of the endemic mammalian fauna of the island. Sportive lemurs have small distribution ranges, fairly small total ... [more ▼]

Biodiversity and endemism is very high in Madagascar and Genus Lepilemur is part of the endemic mammalian fauna of the island. Sportive lemurs have small distribution ranges, fairly small total populations and are particularly negatively affected by deforestation and habitat fragmentation, serious threats for the biological diversity of the island. Our research focus on one poorly-known taxon, Lepilemur mittermeieri. The distribution range of this endangered species is restricted to the Ampasindava peninsula in the northwest Madagascar and ecological information is essential for its preservation. The main objective of our study is to analyze habitat use and niche characteristics of the species and the impact of habitat degradation and fragmentation on these parameters in order to design robust conservation guidelines for the Ampasindava peninsula. In this talk, we will present the project as a whole and results of two 4-months field missions conducted in 2015 and in 2016. These field missions were designed to specifically 1)compare home range size between two sites 2)complete forest characterization of the home range of several radio-collared individuals. The methodology includes the monitoring of 16animals equipped with radio-collar (VHS telemetry) during 6hours per night for a number of days, GPS locations being recorded every 10 minutes. The home range is derived from the telemetry observation through MCP method. [less ▲]

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See detailLes fortifications celtique et carolingienne du Rocher du Vieux-Château à Pont-de-Bonne (Modave, Belgique)
Delye, Emmanuel ULg

Book published by Cercle archéologique Hesbaye-Condroz (2016)

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See detailLa parentalité dans un contexte de violence conjugale : support de résilience ?
Glowacz, Fabienne ULg

Conference (2016, August)

L’accès à la parentalité, quels que soient le contexte social ou conjugal et l’histoire de la femme, s’avère une étape-clé de transition dans la trajectoire personnelle. Le fonctionnement parental est ... [more ▼]

L’accès à la parentalité, quels que soient le contexte social ou conjugal et l’histoire de la femme, s’avère une étape-clé de transition dans la trajectoire personnelle. Le fonctionnement parental est influencé par trois types de facteurs interagissant entre eux : la personnalité du parent (elle-même influencée par son histoire développementale), les caractéristiques individuelles de l'enfant et les sources de soutien et de stress de l'environnement (Belsky,1984).Les recherches sur la parentalité et la résilience se sont principalement centrées sur la résilience des enfants ayant vécu des traumatismes tels que les abus sexuels, où la résilience est activée par la disponibilité et le soutien parental ( Glowacz et Buzitu, 2014). Nos récentes études portant sur les trajectoires de femmes ayant vécu des traumatismes majeurs (violences conjugales, violences de guerre) nous conduisent à considérer l’accès à la parentalité comme un turning point, déclencheur d’un processus de résilience de ces femmes. Des analyses cliniques seront mises en perspective avec des données de recherches ayant évalué le sentiment de compétence parentale (incluant le sentiment d’efficacité et le sentiment de satisfaction), le stress parental et le soutien social perçu de femmes ayant vécu ces traumatismes. Nos observations et résultats nous amènent à questionner la résilience de la mère et les résonances de cette résilience sur l’enfant en développement. [less ▲]

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See detailHigh gene flow between alternative morphs and the evolutionary persistence of facultative paedomorphosis
Oromi Farrús, Neus ULg; Michaux, Johan ULg; Denoël, Mathieu ULg

in Scientific Reports (2016), 6

Paedomorphosis and metamorphosis are two major developmental processes that characterize the evolution of complex life cycles in many lineages. Whereas these processes were fixed in some taxa, they ... [more ▼]

Paedomorphosis and metamorphosis are two major developmental processes that characterize the evolution of complex life cycles in many lineages. Whereas these processes were fixed in some taxa, they remained facultative in others, with alternative phenotypes expressed in the same populations. From a genetic perspective, it is still unknown whether such phenotypes form a single population or whether they show some patterns of isolation in syntopy. This has deep implications for understanding the evolution of the phenotypes, i.e. towards their persistence or their fixation and speciation. Newts and salamanders are excellent models to test this hypothesis because they exhibit both developmental processes in their populations: the aquatic paedomorphs retain gills, whereas the metamorphs are able to colonize land. Using microsatellite data of coexisting paedomorphic and metamorphic palmate newts (Lissotriton helveticus), we found that they formed a panmictic population, which evidences sexual compatibility between the two phenotypes. The high gene flow could be understood as an adaptation to unstable habitats in which phenotypic plasticity is favored over the fixation of developmental alternatives. This makes then possible the persistence of a polyphenism: only metamorphosis could be maintained in case of occasional drying whereas paedomorphosis could offer specific advantages in organisms remaining in water. [less ▲]

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See detailNarrowing the science/policy gap for environmental management
Hughes, Kevin A; Liggett, Daniela; Roldan, Gabriela et al

in Antarctic Science (2016), 28(5), 325

Antarctic terrestrial and marine environments are under increasing pressure from national operator activities, tourism and climate change. The Protocol on Environmental Protection to the Antarctic Treaty ... [more ▼]

Antarctic terrestrial and marine environments are under increasing pressure from national operator activities, tourism and climate change. The Protocol on Environmental Protection to the Antarctic Treaty provides overarching legislation concerning the environmental management of the Treaty area, with 2016 marking the Protocol’s 25th anniversary. The Protocol also established the Committee for Environmental Protection (CEP) to provide advice to the Antarctic Treaty Consultative Meeting (ATCM) on environmental matters. Today, the CEP’s Five-Year Work Plan and Climate Change Response Work Programme lists and prioritises issues that need to be addressed to ensure impacts in Antarctica by human activities are both recognized andminimised.Despite all of this, recent evaluations have suggested that a slow pace of environmental policy development presents a significant threat to effective Antarctic conservation. Progress on many environmental issues, including wildlife disturbance, the conservation status of Antarctic species, area protection and pollution management, is glacial or has stalled completely. Whilst in some cases capacity issues concerning those responsible for Antarctic environmental policy work may be a contributing factor, the level of interaction between researchers and those responsible for environmental management and decision-making is also of importance. Without quality science - and effective interpretation of research results - policymakers have little evidence on which to base their decisions. But researchers need to know policymakers’ needs. Two-way communication is essential: policymakers could ask the research community to answer specific environmental questions, and, in turn, researchers could present evidence-based recommendations and highlight emerging threats. But how is this to be funded? Ultimately, effective communication is needed between national government departments responsible for funding Antarctic research and those dealing with Antarctic environmental protection. Hopefully, this will ensure essential research informing environmental policy decisions is adequately resourced. In reality, the cost is likely to be trivial compared with the resources spent by Parties on Antarctic logistics. [less ▲]

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