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See detailFirst Ground-Based Validation of SCIAMACHY V5.01 Ozone Column
Lambert, Jean-Christopher; Allaart, M; Andersen, S.B. et al

in Proceedings of the Second Workshop on the Atmospheric Chemistry Validation of ENVISAT (ACVE-2), ESA-ESRIN, Frascati, Italy, 3-7 May 2004 (ESA SP-562, August 2004) ESC01JL1 (2004, August)

In early 2004, the near real-time data processor of ENVISAT SCIAMACHY (SCI_NL) was upgraded to version 5.01. Based on the correlative measurements acquired and collected during the commissioning phase of ... [more ▼]

In early 2004, the near real-time data processor of ENVISAT SCIAMACHY (SCI_NL) was upgraded to version 5.01. Based on the correlative measurements acquired and collected during the commissioning phase of the satellite in 2002, a preliminary validation was organised to verify the improvement and assess the geophysical consistency of the new SCIAMACHY ozone vertical column data product. The present overview summarises the results obtained by a list of validation teams and involving ground-based data acquired from pole to pole by complementary ground-based sensors. The studies conclude to an improvement compared to previous versions 3.5x. They also confirm the presence of expected errors (e.g. dependence on solar elevation and on ozone column) inherited from the GOME Data Processor GDP 2.4, on which the SCIAMACHY processor SCI_NL is based. [less ▲]

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See detailFirst HARPSpol discoveries of magnetic fields in massive stars
Alecian, E.; Kochukhov, O.; Neiner, C. et al

in Astronomy and Astrophysics (2011), 536

In the framework of the Magnetism in Massive Stars (MiMeS) project, a HARPSpol Large Program at the 3.6m-ESO telescope has recently started to collect high-resolution spectropolarimetric data of a large ... [more ▼]

In the framework of the Magnetism in Massive Stars (MiMeS) project, a HARPSpol Large Program at the 3.6m-ESO telescope has recently started to collect high-resolution spectropolarimetric data of a large number of Southern massive OB stars in the field of the Galaxy and in many young clusters and associations. We report on the first discoveries of magnetic fields in two massive stars with HARPSpol - HD 130807 and HD 122451, and confirm the presence of a magnetic field at the surface of HD 105382 that was previously observed with a low spectral resolution device. The longitudinal magnetic field measurements strongly vary for HD 130807 from ~-100 G to ~700 G. Those of HD 122451 and HD 105382 are less variable with values ranging from ~-40 to -80 G, and from ~-300 to -600 G, respectively. The discovery and confirmation of three new magnetic massive stars, including at least two He-weak stars, is an important contribution to one of MiMeS objectives: the understanding of the origin of magnetic fields in massive stars and their impact on stellar structure and evolution. Based on observations collected at the European Southern Observatory, Chile (Program ID 187.D-0917). [less ▲]

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See detailFirst High-Angular Resolution L' Images of the β Pictoris Debris Disc with the VLT / NaCo
Milli, Julien; Mawet, Dimitri; Absil, Olivier ULg et al

in Booth, Mark; Matthews, Brenda; Graham, James (Eds.) Exploring the Formation and Evolution of Planetary Systems (2014, January 01)

Imaging debris discs in the L'-band (3.8 μm) is a difficult task. Quasi-static speckles from imperfect optics prevail below 1'' whereas background emission is the dominant noise source beyond that ... [more ▼]

Imaging debris discs in the L'-band (3.8 μm) is a difficult task. Quasi-static speckles from imperfect optics prevail below 1'' whereas background emission is the dominant noise source beyond that separation and is much larger than at shorter wavelengths. We demonstrate here the potential of the newly commissioned AGPM coronograph on VLT/NaCo combined with advanced star and sky subtraction technique based on Principal Component Analysis, and we analyze the morphology of the β Pictoris disc. [less ▲]

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See detailFirst Imaging of Coronal Mass Ejections in the Heliosphere Viewed from Outside the Sun Earth Line
Harrison, Richard A; Davis, Christopher J; Eyles, Christopher J et al

in Solar Physics (2007), 247

We show for the first time images of solar coronal mass ejections (CMEs) viewed using the Heliospheric Imager (HI) instrument aboard the NASA STEREO spacecraft. The HI instruments are wide-angle imaging ... [more ▼]

We show for the first time images of solar coronal mass ejections (CMEs) viewed using the Heliospheric Imager (HI) instrument aboard the NASA STEREO spacecraft. The HI instruments are wide-angle imaging systems designed to detect CMEs in the heliosphere, in particular, for the first time, observing the propagation of such events along the Sun Earth line, that is, those directed towards Earth. At the time of writing the STEREO spacecraft are still close to the Earth and the full advantage of the HI dual-imaging has yet to be realised. However, even these early results show that despite severe technical challenges in their design and implementation, the HI instruments can successfully detect CMEs in the heliosphere, and this is an extremely important milestone for CME research. For the principal event being analysed here we demonstrate an ability to track a CME from the corona to over 40 degrees. The time altitude history shows a constant speed of ascent over at least the first 50 solar radii and some evidence for deceleration at distances of over 20 degrees. Comparisons of associated coronagraph data and the HI images show that the basic structure of the CME remains clearly intact as it propagates from the corona into the heliosphere. Extracting the CME signal requires a consideration of the F-coronal intensity distribution, which can be identified from the HI data. Thus we present the preliminary results on this measured F-coronal intensity and compare these to the modelled F-corona of Koutchmy and Lamy ( IAU Colloq. 85, 63, 1985). This analysis demonstrates that CME material some two orders of magnitude weaker than the F-corona can be detected; a specific example at 40 solar radii revealed CME intensities as low as 1.7×10[SUP]-14[/SUP] of the solar brightness. These observations herald a new era in CME research as we extend our capability for tracking, in particular, Earth-directed CMEs into the heliosphere. [less ▲]

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See detailFirst insights into electrografted polymers by AFM-based force spectroscopy
Cuenot, Stéphane; Gabriel, Sabine ULg; Jérôme, Robert ULg et al

in Macromolecules (2006), 39(24), 8428-8433

The very first characterization of the structural properties of polymer films obtained by electrografting is reported. AFM-based force spectroscopy was used to investigate poly-N-succinimidyl acrylate ... [more ▼]

The very first characterization of the structural properties of polymer films obtained by electrografting is reported. AFM-based force spectroscopy was used to investigate poly-N-succinimidyl acrylate (PNSA) layers electrografted directly from a silicon substrate. Quantitative analysis of compression profiles obtained in a good solvent and single molecule bridging interaction, in light of the Alexander-de Gennes model, gave access to the grafting density and degree of polymerization. A high swelling capacity has been evidenced. This report is the first evidence that polymers obtained by cathodic electrografting are in fact brush systems, and consequently the first evidence that a polymer brush can be obtained from a direct "grafting from" method, without any intermediate layer. [less ▲]

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See detailFirst insights into the gut microflora associated with an echinoid from wood falls environments
Becker, Pierre; Samadi, Sarah; Zbinden, Magali et al

in Cahiers de Biologie Marine (2009), 50

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See detailFirst insights into the molecular basis of pleomorphic adenomas of the salivary glands.
Voz, Marianne ULg; Van de Ven, W. J.; Kas, K.

in Advances in Dental Research (2000), 14

Pleomorphic adenoma, or mixed tumor of the salivary glands, is a benign tumor originating from the major and minor salivary glands. Eighty-five percent of these tumors are found in the parotid gland, 10 ... [more ▼]

Pleomorphic adenoma, or mixed tumor of the salivary glands, is a benign tumor originating from the major and minor salivary glands. Eighty-five percent of these tumors are found in the parotid gland, 10% in the minor (sublingual) salivary glands, and 5% in the submandibular gland. It is the most common type of salivary gland tumor, accounting for almost 50% of all neoplasms in these organs. In fact, after the first observation of recurrent loss of chromosome 22 in meningioma, this was the second type of benign tumor for which non-random chromosomal changes were reported. The rate of malignant change with the potential to metastasize has been reported to be only 2 to 3%, and only a few cases of metastasizing pleomorphic salivary gland adenomas have been described to date. The fact that these tumors arise in organs located in an ontogenetic transitional zone, a region where endoderm and ectoderm meet, might be one of the reasons for the often-problematic histopathological classification. This type of benign tumor has been cytogenetically very well-characterized, with several hundreds of tumors karyotyped. In addition to the cytogenetic subgroup with an apparently normal diploid stemline (making up approximately 30% of the cases), three major cytogenetic subgroups can be distinguished. In addition to a subgroup showing non-recurrent clonal abnormalities, another subgroup is various translocations involving 12q15. By far the largest cytogenetic subgroup, however, consists of tumors with chromosome 8 abnormalities, mainly showing translocations involving region 8q12. The most frequently encountered aberration in this group is a t(3;8)(p21;q12). [less ▲]

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See detailFirst invited discourse during the XXIst General Assembly of the International Astronomical Union "Gravitational lensing"
Refsdal, S.; Surdej, Jean ULg

in Bergeron (Ed.) Highlights of Astronomy, Vol. 9, p.3 (1992)

Not Available

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See detailFirst isolation and molecular characterization of foot-and-mouth disease virus in Benin
Gorna, K; Houndjè, E; Romey, A et al

in Veterinary Microbiology (2014)

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See detailFirst isolation of Parafilaria bovicola from clinically affected cattle in Belgium.
Losson, Bertrand ULg; Saegerman, Claude ULg

in Veterinary Record : Journal of the British Veterinary Association (2009), 164(20), 623-6

The observation of the first two outbreaks of bovine parafilariosis in Belgium led to a preliminary epidemiological investigation conducted through a telephone survey among veterinarians in a limited area ... [more ▼]

The observation of the first two outbreaks of bovine parafilariosis in Belgium led to a preliminary epidemiological investigation conducted through a telephone survey among veterinarians in a limited area around the outbreaks. Typical clinical signs consisting of bleeding spots and areas of oedema were recorded, and the aetiology was confirmed through the observation of typical embryonated eggs of Parafilaria bovicola in the exudate. The localisation of the lesions on the withers, neck, back and, to a smaller extent, the rump of the animals, and their first appearance in early spring, were additional useful epidemiological observations. The clinical herd prevalence in the area was 14.1 per cent (95 per cent confidence interval 11.3 to 17.2 per cent), suggesting that bovine parafilariosis is established in the area. [less ▲]

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See detailFirst Kepler results on compact pulsators - I. Survey target selection and the first pulsators
Ostensen, R. H.; Silvotti, R.; Charpinet, S. et al

in Monthly Notices of the Royal Astronomical Society (2010), 409

We present results from the first two quarters of a survey to search for pulsations in compact stellar objects with the Kepler spacecraft. The survey sample and the various methods applied in its ... [more ▼]

We present results from the first two quarters of a survey to search for pulsations in compact stellar objects with the Kepler spacecraft. The survey sample and the various methods applied in its compilation are described, and spectroscopic observations are presented to separate the objects into accurate classes. From the Kepler photometry we clearly identify nine compact pulsators and a number of interesting binary stars. Of the pulsators, one shows the strong, rapid pulsations typical of a V361 Hya-type sdB variable (sdBV); seven show long-period pulsation characteristics of V1093 Her-type sdBVs; and one shows low-amplitude pulsations with both short and long periods. We derive effective temperatures and surface gravities for all the subdwarf B stars in the sample and demonstrate that below the boundary region where hybrid sdB pulsators are found, all our targets are pulsating. For the stars hotter than this boundary temperature a low fraction of strong pulsators (<10 per cent) is confirmed. Interestingly, the short-period pulsator also shows a low-amplitude mode in the long-period region, and several of the V1093 Her pulsators show low-amplitude modes in the short-period region, indicating that hybrid behaviour may be common in these stars, also outside the boundary temperature region where hybrid pulsators have hitherto been found. [less ▲]

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See detailFirst light of SWAP on-board PROBA2
Halain, Jean-Philippe ULg; Defise, Jean-Marc ULg; Rochus, Pierre ULg et al

in Proceedings of SPIE (2010), 7732

The SWAP telescope (Sun Watcher using Active Pixel System detector and Image Processing) is an instrument launched on 2nd November 2009 on-board the ESA PROBA2 technological mission. SWAP is a space ... [more ▼]

The SWAP telescope (Sun Watcher using Active Pixel System detector and Image Processing) is an instrument launched on 2nd November 2009 on-board the ESA PROBA2 technological mission. SWAP is a space weather sentinel from a low Earth orbit, providing images at 174 nm of the solar corona. The instrument concept has been adapted to the PROBA2 mini-satellite requirements (compactness, low power electronics and a-thermal opto-mechanical system). It also takes advantage of the platform pointing agility, on-board processor, Packetwire interface and autonomous operations. The key component of SWAP is a radiation resistant CMOS-APS detector combined with onboard compression and data prioritization. SWAP has been developed and qualified at the Centre Spatial de Liège (CSL) and calibrated at the PTB-Bessy facility. After launch, SWAP has provided its first images on 14th November 2009 and started its nominal, scientific phase in February 2010, after 3 months of platform and payload commissioning. This paper summarizes the latest SWAP developments and qualifications, and presents the first light results. [less ▲]

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See detailThe first long acting "retard" thymoanaleptic or antidepressant: noveril Tr. statistical addendum
Albert, Adelin ULg; Collard, J.; Fraipont, J. et al

in Arzneimittel Forschung (1973), 4

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See detailA first look at the ASSI ultraviolet results
Chakrabarti, S.; Gladstone, G. R.; Tobiska, W. K. et al

in Advances in Space Research (1993), 13

The Airglow and Solar Spectrometer Instrument (ASSI) on the San Marco D satellite has obtained near-simultaneous measurements of solar irradiances and airglow emissions in the 200-7000 A spectral region ... [more ▼]

The Airglow and Solar Spectrometer Instrument (ASSI) on the San Marco D satellite has obtained near-simultaneous measurements of solar irradiances and airglow emissions in the 200-7000 A spectral region. The satellite was placed in an equatorial, elliptical orbit on 25 March 1988, which permitted observations of airglow emissions in the 280-600-km altitude range at various local times. The instrument complement on the satellite provides an opportunity both for self-consistent examination of the excitation mechanisms of various airglow features and for constraining model parameters. An overview of the data obtained by ASSI is presented along with preliminary modeling results of the UV airglow. [less ▲]

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See detailA First Look at the Nonadiabatic Properties of Pulsating Accreting White Dwarfs of the GW Lib Type
Van Grootel, Valérie ULg; Fontaine, G.; Brassard, P. et al

in Astronomical Society of the Pacific Conference Series (in press)

We present results of a detailed stability survey of the pulsation properties of accreting white dwarfs of the GW Lib type. This is based on several state-of-the- art white dwarf evolutionary sequences ... [more ▼]

We present results of a detailed stability survey of the pulsation properties of accreting white dwarfs of the GW Lib type. This is based on several state-of-the- art white dwarf evolutionary sequences with varying envelope compositions, from pure hydrogen to pure helium. Using the same tools as in Van Grootel et al. (2013), where we have presented the first consistent view of the ZZ Ceti instability strip, we have mapped the GW Lib instability strip over the effective temperature-surface gravity plane, and as a function of envelope composition. We find that the location of the GW Lib instability domain is a strong and continuous function of the assumed envelope composition. We can accomodate all of the known GW Lib pulsators in various strips according to their atmospheric compositions. [less ▲]

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See detailA First Look at the Nonadiabatic Properties of Pulsating Accreting White Dwarfs of the GW Lib Type
Van Grootel, Valérie ULg; Fontaine, G.; Brassard, P. et al

Poster (2014, August)

We present results of a detailed stability survey of the pulsation properties of accreting white dwarfs of the GW Lib type. This is based on several state-of-the- art white dwarf evolutionary sequences ... [more ▼]

We present results of a detailed stability survey of the pulsation properties of accreting white dwarfs of the GW Lib type. This is based on several state-of-the- art white dwarf evolutionary sequences with varying envelope compositions, from pure hydrogen to pure helium. Using the same tools as in Van Grootel et al. (2013), where we have presented the first consistent view of the ZZ Ceti instability strip, we have mapped the GW Lib instability strip over the effective temperature-surface gravity plane, and as a function of envelope composition. We find that the location of the GW Lib instability domain is a strong and continuous function of the assumed envelope composition. We can accomodate all of the known GW Lib pulsators in various strips according to their atmospheric compositions. [less ▲]

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See detailFirst Magnetic Field Models for Recently Discovered Magnetic β Cephei and Slowly Pulsating B Stars
Hubrig, S.; Schöller, M.; Ilyin, I. et al

in Progress in Solar/Stellar Physics with Helio- and Asteroseismology (2012, September 01)

Despite of the importance of magnetic fields for the full understanding of the properties of pulsating β Cephei and slowly pulsating B (SPB) stars, these fields have scarcely been studied over the ... [more ▼]

Despite of the importance of magnetic fields for the full understanding of the properties of pulsating β Cephei and slowly pulsating B (SPB) stars, these fields have scarcely been studied over the rotation cycle until now. During the past two years we have obtained multi-epoch polarimetric spectra of several β Cephei and SPB stars with FORS 2 at the Very Large Telescope and SOFIN at the Nordic Optical Telescope to search for a rotation period and to constrain the geometry of the magnetic field. The rotation periods and magnetic field geometries were determined for three β Cephei stars, ℰ[SUP]1[/SUP] CMa, 15 CMa, and V1449 Aql, the candidate β Cephei star α Pyx, and the SPB star 33 Eri. [less ▲]

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See detailFirst Magnetic Field Models for Recently Discovered Magnetic β Cephei and Slowly Pulsating B Stars
Hubrig, S.; Ilyin, Ilya; Schöller, Markus et al

in Astrophysical Journal Letters (2011), 726

In spite of recent detections of magnetic fields in a number of β Cephei and slowly pulsating B (SPB) stars, their impact on stellar rotation, pulsations, and element diffusion has not yet been ... [more ▼]

In spite of recent detections of magnetic fields in a number of β Cephei and slowly pulsating B (SPB) stars, their impact on stellar rotation, pulsations, and element diffusion has not yet been sufficiently studied. The reason for this is the lack of knowledge of rotation periods, the magnetic field strength distribution and temporal variability, and the field geometry. New longitudinal field measurements of four β Cephei and candidate β Cephei stars, and two SPB stars were acquired with FORS 2 at the Very Large Telescope. These measurements allowed us to carry out a search for rotation periods and to constrain the magnetic field geometry for four stars in our sample. Based on observations obtained at the European Southern Observatory (ESO programme 084.D-0230(A)). [less ▲]

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See detailFirst manufactured diamond AGPM vector vortex for the L- and N-bands: metrology and expected performances
Delacroix, Christian ULg; Forsberg, Pontus; Karlsson, Mikael et al

Conference (2010, October 28)

The AGPM (Annular Groove Phase Mask, Mawet et al. 2005) is an optical vectorial vortex coronagraph (or vector vortex) synthesized by a circular subwavelength grating, that is a grating with a period ... [more ▼]

The AGPM (Annular Groove Phase Mask, Mawet et al. 2005) is an optical vectorial vortex coronagraph (or vector vortex) synthesized by a circular subwavelength grating, that is a grating with a period smaller than λ/n (λ being the observed wavelength and n the refractive index of the grating substrate). Since it is a phase mask, it allows to reach a high contrast with a small working angle. Moreover, its subwavelength structure provides a good achromatization over wide spectral bands. Recently, we have manufactured and measured our first N-band prototypes that allowed us to validate the reproducibility of the microfabrication process. Here, we present newly produced mid-IR diamond AGPMs in the N-band (~10 µm), and in the most wanted L-band (~3.5 µm). We first give an extrapolation of the expected coronagraph performances. We then present the manufacturing and measurement results, using diamond-optimized microfabrication techniques such as nano-imprint lithography (NIL) and reactive ion etching (RIE). Finally, the subwavelength grating profile metrology combines surface metrology (scanning electron microscopy, atomic force microscopy, white light interferometry) with diffractometry on an optical polarimetric bench and cross correlation with theoretical simulations using rigorous coupled wave analysis (RCWA). [less ▲]

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See detailA First Measurement Look at the Deployment and Evolution of the Locator/ID Separation Protocol
Saucez, Damien; Iannone, Luigi; Donnet, Benoît ULg

in Computer Communication Review (2013), 43(1), 37-43

During the last decade, we have seen the rise of discussions regarding the emergence of a Future Internet. One of the proposed approaches leverages on the separation of the identifier and the locator ... [more ▼]

During the last decade, we have seen the rise of discussions regarding the emergence of a Future Internet. One of the proposed approaches leverages on the separation of the identifier and the locator roles of IP addresses, leading to the LISP (Locator/Identifier Separation Protocol) protocol, currently under development at the IETF (Internet Engineering Task Force). Up to now, researches made on LISP have been rather theoretical, i.e., based on simulations/emulations often using Internet traffic traces. There is no work in the literature attempting to assess the state of its deployment and how this has evolved in recent years. This paper aims at bridging this gap by presenting a first measurement study on the existing worldwide LISP network (lisp4.net). Early results indicate that there is a steady growth of the LISP network but also that network manageability might receive a higher priority than performance in a large scale deployment. [less ▲]

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