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See detailExome sequencing in Brown-Vialetto-van Laere syndrome.
Johnson, Janel O; Gibbs, J Raphael; Van Maldergem, Lionel ULg et al

in American Journal of Human Genetics (2010), 87(4), 567-9569-70

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See detailExonic deletions in AUTS2 cause a syndromic form of intellectual disability and suggest a critical role for the C terminus.
Beunders, Gea; Voorhoeve, Els; Golzio, Christelle et al

in American journal of human genetics (2013), 92(2), 210-20

Genomic rearrangements involving AUTS2 (7q11.22) are associated with autism and intellectual disability (ID), although evidence for causality is limited. By combining the results of diagnostic testing of ... [more ▼]

Genomic rearrangements involving AUTS2 (7q11.22) are associated with autism and intellectual disability (ID), although evidence for causality is limited. By combining the results of diagnostic testing of 49,684 individuals, we identified 24 microdeletions that affect at least one exon of AUTS2, as well as one translocation and one inversion each with a breakpoint within the AUTS2 locus. Comparison of 17 well-characterized individuals enabled identification of a variable syndromic phenotype including ID, autism, short stature, microcephaly, cerebral palsy, and facial dysmorphisms. The dysmorphic features were more pronounced in persons with 3'AUTS2 deletions. This part of the gene is shown to encode a C-terminal isoform (with an alternative transcription start site) expressed in the human brain. Consistent with our genetic data, suppression of auts2 in zebrafish embryos caused microcephaly that could be rescued by either the full-length or the C-terminal isoform of AUTS2. Our observations demonstrate a causal role of AUTS2 in neurocognitive disorders, establish a hitherto unappreciated syndromic phenotype at this locus, and show how transcriptional complexity can underpin human pathology. The zebrafish model provides a valuable tool for investigating the etiology of AUTS2 syndrome and facilitating gene-function analysis in the future. [less ▲]

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See detailExophthalmos and strabismus associated with a frontal mucocele in a 6-month-old puppy
Monclin, Sébastien ULg; Saulnier-Troff F.; Bolen, Géraldine ULg et al

Poster (2008, May)

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See detailExoplanet Characterization and the Search for Life
Kasting, J.; et al.; Hanot, Charles ULg et al

E-print/Working paper (2009)

Over 300 extrasolar planets (exoplanets) have been detected orbiting nearby stars. We now hope to conduct a census of all planets around nearby stars and to characterize their atmospheres and surfaces ... [more ▼]

Over 300 extrasolar planets (exoplanets) have been detected orbiting nearby stars. We now hope to conduct a census of all planets around nearby stars and to characterize their atmospheres and surfaces with spectroscopy. Rocky planets within their star's habitable zones have the highest priority, as these have the potential to harbor life. Our science goal is to find and characterize all nearby exoplanets; this requires that we measure the mass, orbit, and spectroscopic signature of each one at visible and infrared wavelengths. The techniques for doing this are at hand today. Within the decade we could answer long-standing questions about the evolution and nature of other planetary systems, and we could search for clues as to whether life exists elsewhere in our galactic neighborhood. [less ▲]

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See detailExoplanet discoveries with the CoRoT space observatory
Lammer, H.; Dvorak, R.; Deleuil, M. et al

in Solar System Research (2010), 44

The CoRoT space observatory is a project which is led by the French space agency CNES and leading space research institutes in Austria, Brazil, Belgium, Germany and Spain and also the European Space ... [more ▼]

The CoRoT space observatory is a project which is led by the French space agency CNES and leading space research institutes in Austria, Brazil, Belgium, Germany and Spain and also the European Space Agency ESA. CoRoT observed since its launch in December 27, 2006 about 100 000 stars for the exoplanet channel, during 150 days uninterrupted high-precision photometry. Since the The CoRoT-team has several exoplanet candidates which are currently analyzed under its study, we report here the discoveries of nine exoplanets which were observed by CoRoT. Discovered exoplanets such as CoRoT-3b populate the brown dwarf desert and close the gap of measured physical properties between usual gas giants and very low mass stars. CoRoT discoveries extended the known range of planet masses down to about 4.8 Earth-masses (CoRoT-7b) and up to 21 Jupiter masses (CoRoT-3b), the radii to about 1.68 × 0.09 R [SUB]Earth[/SUB] (CoRoT-7b) and up to the most inflated hot Jupiter with 1.49 × 0.09 R [SUB]Earth[/SUB] found so far (CoRoT-1b), and the transiting exoplanet with the longest period of 95.274 days (CoRoT-9b). Giant exoplanets have been detected at low metallicity, rapidly rotating and active, spotted stars. Two CoRoT planets have host stars with the lowest content of heavy elements known to show a transit hinting towards a different planethost-star-metallicity relation then the one found by radial-velocity search programs. Finally the properties of the CoRoT-7b prove that rocky planets with a density close to Earth exist outside the Solar System. Finally the detection of the secondary transit of CoRoT-1b at a sensitivity level of 10[SUP]-5[/SUP] and the very clear detection of the "super-Earth" CoRoT-7b at 3.5 × 10[SUP]-4[/SUP] relative flux are promising evidence that the space observatory is being able to detect even smaller exoplanets with the size of the Earth. [less ▲]

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See detailExoplanet imaging with mid-infrared vector vortex coronagraphs: design, manufacture, validation and first light of the annular groove phase mask
Delacroix, Christian ULg

Doctoral thesis (2013)

During the past twenty years, detections of extrasolar planets have flourished and grown expo- nentially, reaching almost 900 confirmed exoplanets so far. This number is doubling every two or three years ... [more ▼]

During the past twenty years, detections of extrasolar planets have flourished and grown expo- nentially, reaching almost 900 confirmed exoplanets so far. This number is doubling every two or three years. The most recent discoveries made by the Kepler mission have revealed two Earth- size exoplanets orbiting the same star, and fulfilling all the required conditions to be habitable. Imaging techniques have also come a long way. Since the first direct detection in 2004, some stunning exoplanet pictures have been captured at the telescope under special circumstances of moderate contrast and/or angular separation, thanks to the advent and continuous improvement of adaptive optics systems and data reduction methods. In this broad context, the need for high contrast imaging techniques with very small inner working angles has never been so strong. Coro- nagraphy has a key role to play in order to provide the means necessary for imaging Earth-size planets, and try to answer the recurring question of the possible presence of life outside the solar system. The present thesis is dedicated to the development of the annular groove phase mask (AGPM), a specific type of broadband vector vortex coronagraph based on subwavelength gratings. Consid- ered for several years as one of the best solutions for building high-performance mid-infrared coron- agraphs with small inner working angles, the AGPM has never been validated up to now. Although various fabrication processes are available, depending on the substrates and micro-lithography techniques considered, they often face extremely challenging constraints. In the present work, we explored the feasibility of achromatic micro-components made out of subwavelength gratings, for which two technological solutions are followed: quartz and diamond. As we focussed on the diamond option, its unique material properties making it a prime candidate for mid-infrared ap- plications, we managed to develop mid-infrared broadband half-wave plates, ideally optimized to enable the manufacturing of charge-2 vortices. Following this success, we continued our devel- opments leading to the fabrication of several AGPMs for two astronomic windows, the L and N bands, and we successfully validated several L-band AGPMs on a coronagraphic test bench at the Observatoire de Paris. In the last chapter, we expose the recent installation of our components on three world-class infrared cameras, VISIR and NACO at the Very Large Telescope in Chile, and LMIRCam at the Large Binocular Telescope in Arizona. We conclude with the very first on-sky results of both N-band and L-band AGPMs, and the discovery and successful imaging of a faint stellar companion at two beamwidths from an F-type star. [less ▲]

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See detailExopolysaccharides production by selected bacteria
Valepyn, Emmanuel ULg; Paquot, Michel ULg; Nys, Joël

Poster (2011, August)

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See detailExosites Mediate The Anti-Inflammatory Effects Of A Multifunctional Serpin From The Saliva Of The Tick Ixodes Ricinus
Prevot, Pp.; Beschin, A.; Lins, Laurence ULg et al

in Febs Journal (2009), 276(12),

Serine protease inhibitors (serpins) are a structurally related but functionally diverse family of ubiquitous proteins. We previously described Ixodes ricinus immunosuppressor (Iris) as a serpin from the ... [more ▼]

Serine protease inhibitors (serpins) are a structurally related but functionally diverse family of ubiquitous proteins. We previously described Ixodes ricinus immunosuppressor (Iris) as a serpin from the saliva of the tick I. ricinus displaying high affinity for human leukocyte elastase. Iris also displays pleotropic effects because it interferes with both the immune response and hemostasis of the host. It thus inhibits lymphocyte proliferation and the secretion of interferon-gamma or tumor necrosis factor-alpha by peripheral blood mononuclear cells, and also platelet adhesion, coagulation and fibrinolysis. Its ability to interfere with coagulation and fibrinolysis, but not platelet adhesion, depends on the integrity of its antiproteolytic reactive center loop domain. Here, we dissect the mechanisms underlying the interaction of recombinant Iris with peripheral blood mononuclear cells. We show that Iris binds to monocytes/macrophages and inhibits their ability to secrete tumor necrosis factor-alpha. Recombinant Iris also has a protective role in endotoxemic shock. The anti-inflammatory ability of Iris does not depend on its antiprotease activity. Moreover, we pinpoint the exosites involved in this activity. [less ▲]

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See detailExotic animal dermatology
Mignon, Bernard ULg; Losson, Bertrand ULg

Conference (2004)

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See detailEXOTIME: searching for planets around pulsating subdwarf B stars
Schuh, Sonja; Silvotti, Roberto; Lutz, Ronny et al

in Astrophysics & Space Science (2010, October), 329

In 2007, a companion with planetary mass was found around the pulsating subdwarf B star V391 Pegasi with the timing method, indicating that a previously undis- covered population of substellar companions ... [more ▼]

In 2007, a companion with planetary mass was found around the pulsating subdwarf B star V391 Pegasi with the timing method, indicating that a previously undis- covered population of substellar companions to apparently single subdwarf B stars might exist. Following this serendip- itous discovery, the EXOTIME (http://www.na.astro.it/ ~silvotti/exotime/) monitoring program has been set up to follow the pulsations of a number of selected rapidly pul- sating subdwarf B stars on time scales of several years with two immediate observational goals: (1) determine P ̇ of the pulsational periods P (2) search for signatures of substellar companions in O– C residuals due to periodic light travel time variations, which would be tracking the central star’s companion- induced wobble around the centre of mass These sets of data should therefore, at the same time, on the one hand be useful to provide extra constraints for classical asteroseismological exercises from the P ̇ (comparison with “local” evolutionary models), and on the other hand allow one to investigate the preceding evolution of a target in terms of possible “binary” evolution by extending the otherwise unsuccessful search for companions to potentially very low masses. While timing pulsations may be an observationally ex- pensive method to search for companions, it samples a dif- ferent range of orbital parameters, inaccessible through or- bital photometric effects or the radial velocity method: the latter favours massive close-in companions, whereas the timing method becomes increasingly more sensitive toward wider separations. In this paper we report on the status of the on-going ob- servations and coherence analysis for two of the currently five targets, revealing very well-behaved pulsational charac- teristics in HS 0444+0458, while showing HS 0702+6043 to be more complex than previously thought. [less ▲]

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See detailL'exotisme intérieur. Lévi-Strauss et la question de l'art
Steinmetz, Rudy ULg

in Art&Fact (1990)

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See detailExotisme zonder romantiek. Roel Janssen en Dorine Platenga: 'Brazilië'
Vanden Berghe, Kristine ULg

Article for general public (1992)

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See detailExozodiacal discs with ALADDIN: how deep can we go?
Absil, Olivier ULg

Scientific conference (2009, May 12)

Studying the warm inner part of debris discs—-the extrasolar counterparts of the zodiacal dust cloud-—is of prime importance to characterise the global architecture of planetary systems. Furthermore, the ... [more ▼]

Studying the warm inner part of debris discs—-the extrasolar counterparts of the zodiacal dust cloud-—is of prime importance to characterise the global architecture of planetary systems. Furthermore, the possible presence of large quantities of warm dust around nearby main sequence stars is unanimously recognised as a major threat for future space missions dedicated to the direct detection and characterisation of Earth-like planets (either with visible/near-IR coronagraphy or mid-infrared interferometry). As of today, exozodiacal discs have been directly resolved around very few main sequence stars, at a sensitivity level of about 1000 times our zodiacal dust cloud. In this context, the ALADDIN project aims at detecting warm dust populations around nearby main sequence stars with significantly improved sensitivity. In this paper, we present a thorough study of ALADDIN's estimated performance. End-to-end simulations taking into account the specific characteristics of the Antarctic environment have been carried out, showing that a nulling interferometer coupled to a pair of 1-m class telescopes in Antarctica would perform significantly better than a similar instrument working on 8-m class telescopes in a temperate site. Exozodiacal dust density levels as low as 50 times the Solar zodiacal cloud are within reach around most Solar-type stars within 25 pc. Such performance would bring the study of exozodiacal light to a new level, and enable a fine study of terrestrial planet environments. Suitable candidate targets for direct Earth-like planet detection could then be identified among nearby main sequence stars in the Southern hemisphere, and the design of future space missions tuned to cope with the statistical occurrence of bright exozodiacal discs. [less ▲]

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See detailExozodiacal discs with ALADDIN: how faint can we detect them?
Absil, Olivier ULg; Coudé Du Foresto; Barillot, M. et al

in Spinoglio, L.; Epchtein, N. (Eds.) 3rd ARENA Conference: An Astronomical Observatory at CONCORDIA (Dome C, Antarctica) (2010)

In this paper, we describe the expected performance of ALADDIN, a nulling interferometer project optimised for operation at Dome C. After reviewing the main atmospheric parameters pertaining to infrared ... [more ▼]

In this paper, we describe the expected performance of ALADDIN, a nulling interferometer project optimised for operation at Dome C. After reviewing the main atmospheric parameters pertaining to infrared interferometry on the high Antarctic plateau, we shortly describe the ALADDIN instrument and compute its estimated performance in terms of the smallest exozodiacal dust disc density that can be detected. Our estimations are based on a thorough end-to-end software simulator previously developed for the GENIE nulling interferometer project at VLTI. We then propose a possible mission scenario, where the southern target stars of future exo-Earth characterisation missions can be surveyed for the presence of bright exozodiacal discs (>50 zodi) within one winter-over at Concordia. [less ▲]

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See detailExozodiacal discs with infrared interferometry
Absil, Olivier ULg

Scientific conference (2007, March 05)

The detection of the warm inner part of debris discs---the extrasolar counterparts of the zodiacal cloud---is of prime importance to characterise the global architecture of planetary systems. Because of ... [more ▼]

The detection of the warm inner part of debris discs---the extrasolar counterparts of the zodiacal cloud---is of prime importance to characterise the global architecture of planetary systems. Because of the high contrast and small angular separation between the star and the exozodiacal light, high-precision infrared interferometry is the best-suited tool to carry out such observations. In this paper, we review the first detection of an exozodiacal disc by this method recently reported around Vega by Absil et al. (2006), and discuss the currently on-going observing efforts in this domain. We show how interferometric data can give access to the composition and the dynamics (including LHB-like events) of extrasolar planetary systems, and thereby put useful constraints on the presence of small bodies and/or giant planets. This statement is illustrated with new data obtained on various bright Vega-type stars, including Vega itself. Finally, we show how the new generation of interferometric instruments will change our view of debris discs: with their increased sensitivity and imaging capabilities, they will constrain the morphology of bright exozodiacal discs and push the detection limit towards meaningful density levels in the context of future life-finding missions such as Darwin/TPF. [less ▲]

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See detailExozodiacal Disks
Hinz, Phillip; Millan-Gabet, Rafael; Absil, Olivier ULg et al

in Lawson, P. R.; Traub, W. A.; Unwin, S. C. (Eds.) Exoplanet Community Report (2009)

From the viewpoint of direct imaging of exoplanets in the visible or infrared, exozodi dust disks can be both good and bad. An exozodi disk is good if it has structures (cleared regions or resonant clumps ... [more ▼]

From the viewpoint of direct imaging of exoplanets in the visible or infrared, exozodi dust disks can be both good and bad. An exozodi disk is good if it has structures (cleared regions or resonant clumps) that suggest the gravitational presence of planets, however it is bad if the dust fills the instrumental field of view with brightness that swamps the signal from a planet. Unfortunately, it takes very little dust to compete with or overwhelm the light from a planet: an Earth‐twin signal is roughly equal to a 0.1‐AU patch of Solar‐System‐twin zodi, in the visible or infrared. Thus, exozodi measurements are extremely important, but they are also difficult to make. Current limits of detection, in units of the Solar‐System brightness, are a few hundred using the Spitzer Space Telescope, about one hundred with the Keck Interferometer (KI), and about 10 expected from the Large Binocular Telescope Interferometer (LBTI). A small coronagraph or small interferometer in space is needed in order to reach the sensitivity required to detect the glow at the level of our own Solar System. [less ▲]

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