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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 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 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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See detailFirst measurements of the HCFC-142b trend from atmospheric chemistry experiment (ACE) solar occultation spectra
Rinsland, Curtis P; Chiou, Linda; Boone, Chris et al

in Journal of Quantitative Spectroscopy & Radiative Transfer (2009), 110(18), 2127-2134

The first measurement of the HCFC-142b (CH3CClF2) trend near the tropopause has been derived from volume mixing ratio (VMR) measurements at northern and southern hemisphere mid-latitudes for the 2004-2008 ... [more ▼]

The first measurement of the HCFC-142b (CH3CClF2) trend near the tropopause has been derived from volume mixing ratio (VMR) measurements at northern and southern hemisphere mid-latitudes for the 2004-2008 time period from spaceborne solar occultation observations recorded at 0.02 cm(-1) resolution with the ACE (atmospheric chemistry experiment) Fourier transform spectrometer. The HCFC-142b molecule is currently the third most abundant HCFC (hydrochlorofluorocarbon) in the atmosphere and ACE measurements over this time span show a continuous rise in its volume mixing ratio. Monthly average measurements at northern and southern hemisphere mid-latitudes have similar increase rates that are consistent with surface trend measurements for a similar time span. A mean northern hemisphere profile for the time span shows a near constant VMR at 8-20 km altitude range, consistent on average for the same time span with in situ results. The nearly constant vertical VMR profile also agrees with model predictions of a long lifetime in the lower atmosphere. (c) 2009 Elsevier Ltd. All rights reserved. [less ▲]

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See detailFirst Molecular Evidence of Potentially Zoonotic Babesia microti and Babesia sp. EU1 in Ixodes ricinus Ticks in Belgium
Lempereur, Laetitia ULg; De Cat, Ann; Caron, Yannick ULg et al

in Vector Borne & Zoonotic Diseases (2011), 11(2), 125-30

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See detailFirst nationwide survey on cardiovascular risk factors in Grand-Duchy of Luxembourg (ORISCAV-LUX)
Alkerwi, A; Sauvageot, N; Donneau, Anne-Françoise ULg et al

Poster (2010)

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See detailFirst nationwide survey on cardiovascular risk factors in Grand-Duchy of Luxembourg (ORISCAV-LUX).
Alkerwi, Ala'a; Sauvageot, Nicolas; Donneau, Anne-Françoise ULg et al

in BMC Public Health (2010), 10

BACKGROUND: The ORISCAV-LUX study is the first baseline survey of an on-going cardiovascular health monitoring programme in Grand-Duchy of Luxembourg. The main objectives of the present manuscript were 1 ... [more ▼]

BACKGROUND: The ORISCAV-LUX study is the first baseline survey of an on-going cardiovascular health monitoring programme in Grand-Duchy of Luxembourg. The main objectives of the present manuscript were 1) to describe the study design and conduct, and 2) to present the salient outcomes of the study, in particular the prevalence of the potentially modifiable and treatable cardiovascular disease risk factors in the adult population residing in Luxembourg. METHOD: ORISCAV-LUX is a cross-sectional study based on a random sample of 4496 subjects, stratified by gender, age categories and district, drawn from the national insurance registry of 18-69 years aged Luxembourg residents, assuming a response rate of 30% and a proportion of 5% of institutionalized subjects in each stratum. The cardiovascular health status was assessed by means of a self-administered questionnaire, clinical and anthropometric measures, as well as by blood, urine and hair examinations. The potentially modifiable and treatable risk factors studied included smoking, hypertension, dyslipidemia, diabetes mellitus, and obesity. Both univariate and multivariate statistical analyses used weighted methods to account for the stratified sampling scheme. RESULTS: A total of 1432 subjects took part in the survey, yielding a participation rate of 32.2%. This figure is higher than the minimal sample size of 1285 subjects as estimated by power calculation. The most predominant cardiovascular risk factors were dyslipidemia (69.9%), hypertension (34.5%), smoking (22.3%), and obesity (20.9%), while diabetes amounted 4.4%. All prevalence rates increased with age (except smoking) with marked gender differences (except diabetes). There was a significant difference in the prevalence of hypertension and of lipid disorders by geographic region of birth. The proportion of subjects cumulating two or more cardiovascular risk factors increased remarkably with age and was more predominant in men than in women (P<0.0001). Only 14.7% of men and 23.1% of women were free of any cardiovascular risk factor. High prevalence of non-treated CVRF, notably for hypertension and dyslipidemia, were observed in the study population. CONCLUSION: The population-based ORISCAV-LUX survey revealed a high prevalence of potentially modifiable and treatable cardiovascular risk factors among apparently healthy subjects; significant gender and age-specific differences were seen not only for single but also for combined risk factors. From a public health perspective, these preliminary findings stress the urgent need for early routine health examinations, preventive interventions and lifestyle behavioural changes, even in young asymptomatic adults, to decrease cardiovascular morbidity and mortality in Luxembourg. [less ▲]

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See detailFirst occurrence of the lungfish Sagenodus (Dipnoi, Sarcopterygii) from the Carboniferous Lagerstätte of Montceau-les-Mines, France
Olive, Sébastien ULg; Clément, Gaël; Pouillon, Jean-Marc

in Journal of Vertebrate Paleontology (2012), 32(2), 285-295

New material of the dipnoan genus Sagenodus is described from the Carboniferous Lagerstätte of Montceau-les-Mines, Massif Central, France. This is the first occurrence of this lungfish in France, thus ... [more ▼]

New material of the dipnoan genus Sagenodus is described from the Carboniferous Lagerstätte of Montceau-les-Mines, Massif Central, France. This is the first occurrence of this lungfish in France, thus enlarging its worldwide distribution; and the first occurrence of a lungfish in Montceau-les-Mines, thus increasing the vertebrate taxa list of this Lagerstätte. This material is Stephanian B in age, the previously established geological range of this Euramerican genus. Remains consist of skull, lower jaw, operculum, and shoulder girdle elements closely set together with several ribs. This material, here considered as belonging to a single disarticulated specimen, shows strong affinities with the material of Sagenodus sp. from Germany and appears significantly different from all other known species of Sagenodus by the shape and ridge pattern of the upper tooth plate. However, this new material can only be attributed to Sagenodus sp. due to its incompleteness. In the literature, Montceau-les-Mines is either interpreted as a freshwater environment or as a coastal marine to marine-influenced environment. As Sagenodus is a euryhaline genus; its presence in this locality does not bring arguments to one or the other assumption. The strong affinities, existing between the material from France and Germany, indicate that there were solid hydrographic links between both basins during the Stephanian B–Upper Rotliegend period. [less ▲]

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See detailFirst occurrence of the lungfish Sagenodus (Dipnoi, Sarcopterygii) from the Carboniferous Lagerstätte of Montceau-les-Mines, France
Olive, Sébastien ULg; Clément, Gaël; Pouillon, Jean-Marc

in Ichthyolith Issues (2011)

New material of the dipnoan genus Sagenodus is described from the Carboniferous of the Barrat quarry (Blanzy-Creuzot coal basin, Montceau-les-Mines, France). This is the first occurrence of this lungfish ... [more ▼]

New material of the dipnoan genus Sagenodus is described from the Carboniferous of the Barrat quarry (Blanzy-Creuzot coal basin, Montceau-les-Mines, France). This is the first occurrence of this lungfish in France, which enlarges its distribution within Europe (Fritsch, 1888; Schultze, 1993; Watson and Gill, 1923). This material is Stephanian B in age, the previously established geological range of this Euramerican (Schultze and Chorn, 1997) genus. Remains consist of skull, lower jaw and shoulder girdle elements, closely set together with many ribs. This material, considered as belonging to a single disarticulated specimen, presents affinities with the material of Sagenodus sp. from Germany (Schultze, 1993) and appears significantly different to all other known Sagenodus species. However this new material can only be attributed to Sagenodus sp. because of its incompleteness. Montceau-les-Mines is interpreted as a freshwater environment deposit and the presence of Sagenodus in this locality confirms that most of the localities of Sagenodus are freshwater deposits. The strong affinities, existing between the material from France and Germany, indicate that there were solid hydrographic links between both basins during the Stephanian B–Upper Rotliegend period. [less ▲]

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See detailThe first orbital solution for the massive colliding-wind binary HD 93162 ( WR 25)
Gamen, R.; Gosset, Eric ULg; Morrell, N. et al

in Astronomy and Astrophysics (2006), 460(3), 777-782

Context. Since the discovery, with the EINSTEIN satellite, of strong X-ray emission associated with HD 93162 (equivalent to WR 25), this object has been predicted to be a colliding-wind binary system ... [more ▼]

Context. Since the discovery, with the EINSTEIN satellite, of strong X-ray emission associated with HD 93162 (equivalent to WR 25), this object has been predicted to be a colliding-wind binary system. However, radial-velocity variations that would prove the suspected binary nature have yet to be found. Aims. We spectroscopically monitored this object to investigate its possible variability to address this discordance. Methods. We compiled the largest available radial-velocity data set for this star to look for variations that might be due to binary motion. We derived radial velocities from spectroscopic data acquired mainly between 1994 and 2006, and searched these radial velocities for periodicities using different numerical methods. Results. For the first time, periodic radial-velocity variations are detected. Our analysis definitively shows that the Wolf-Rayet star WR 25 is an eccentric binary system with a probable period of about 208 days. [less ▲]

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See detailThe first orbital solution for the massive colliding-wind binary HD 93162 (=WR 25)
Gamen, R.; Gosset, Eric ULg; Morrell, N. I. et al

in Revista Mexicana de Astronomia y Astrofisica Conference Series (2008, August 01)

Since the discovery, with EINSTEIN, of strong X-ray emission associated with HD 93162, this object was recurrently predicted by some authors to be a colliding-wind binary system. However, radial-velocity ... [more ▼]

Since the discovery, with EINSTEIN, of strong X-ray emission associated with HD 93162, this object was recurrently predicted by some authors to be a colliding-wind binary system. However, radial-velocity variations that would prove the suspected binary nature have never been found so far. We spectroscopically monitored this object in order to investigate its possible variability and to provide an answer to the above-mentioned discordance. We derived radial velocities from spectroscopic data acquired mainly between 1994 and 2006, and searched for periodicities. For the first time, periodic radial-velocity variations are detected. Our analysis definitively shows that the Wolf-Rayet star WR 25 is actually an eccentric binary system with a probable period of about 208 days. [less ▲]

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See detailFirst Orbital Solution for the Non-thermal Emitter Cyg OB2 No. 9
Nazé, Yaël ULg; Damerdji, Yassine ULg; Rauw, Grégor ULg et al

in Astrophysical Journal (2010), 719

After the first detection of its binary nature, the spectroscopic monitoring of the non-thermal radio emitter Cyg OB2 No. 9 (P = 2.4 yr) has continued, doubling the number of available spectra of the star ... [more ▼]

After the first detection of its binary nature, the spectroscopic monitoring of the non-thermal radio emitter Cyg OB2 No. 9 (P = 2.4 yr) has continued, doubling the number of available spectra of the star. Since the discovery paper of 2008, a second periastron passage has occurred in 2009 February. Using a variety of techniques, the radial velocities could be estimated and a first, preliminary orbital solution was derived from the He I 5876 line. The mass ratio appears close to unity and the eccentricity is large, i.e., 0.7-0.75. X-ray data from 2004 and 2007 are also analyzed in quest of peculiarities linked to binarity. The observations reveal neither large overluminosity nor strong hardness, but it must be noted that the high-energy data were taken after the periastron passage, at a time where colliding wind emission may be low. Some unusual X-ray variability is however detected, with a 10% flux decrease between 2004 and 2007. To clarify their origin and find a more obvious signature of the wind-wind collision, additional data, taken at periastron and close to it, are needed. Based on observations collected at the Haute-Provence Observatory and with XMM-Newton, an ESA Science Mission with instruments and contributions directly funded by ESA Member States and the USA (NASA). [less ▲]

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See detailA first orbital solution for the non-thermal radio emitter Cyg OB2 #9
Nazé, Yaël ULg; Damerdji, Yassine ULg; Rauw, Grégor ULg et al

in Bulletin de la Société Royale des Sciences de Liège (2011), 80

We reported in 2008 the first detection of the binary nature of Cyg OB2 #9. Since then, we have continued our spectroscopic monitoring of this object, doubling the number of available spectra of the star ... [more ▼]

We reported in 2008 the first detection of the binary nature of Cyg OB2 #9. Since then, we have continued our spectroscopic monitoring of this object, doubling the number of available spectra of the star while covering a second periastron passage. Using a variety of techniques, the radial velocities were estimated and a first, preliminary orbital solution was derived (P=2.4 yrs). The mass ratio appears close to unity and the eccentricity is large, 0.7-0.75. [less ▲]

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See detailFirst order elastic modeling of the Aden ridge propagation and the Anatolian extrusion process
Hubert, Aurelia ULg; King, G. C. P.; Manighetti, I. et al

in Geophysical Journal International (2003), 153

The evolution of the Gulf of Aden and the Anatolian Fault systems are modelled using the principles of elastic fracture mechanics usually applied to smaller scale cracks or faults. The lithosphere is ... [more ▼]

The evolution of the Gulf of Aden and the Anatolian Fault systems are modelled using the principles of elastic fracture mechanics usually applied to smaller scale cracks or faults. The lithosphere is treated as a plate, and simple boundary conditions are applied that correspond to the known plate boundary geometry and slip vectors. The models provide a simple explanation for many observed geological features. For the Gulf of Aden the model predicts why the ridge propagated from east to west from the Owen Fracture Zone towards the Afar and the overall form of its path. The smaller en echelon offsets can be explained by upward propagation from the initially created mantle dyke while the larger ones may be attributed to the propagating rupture interacting with pre-existing structures. For Anatolia the modelling suggests that the East Anatolian Fault was created before the North Anatolian Fault could form. Once both faults were formed however, activity could switch between them. The time scales over which this should take place are not known, but evidence for switching can be found in the historical seismicity. For Aden and Anatolia pre-existing structures or inhomogeneous stress fields left from earlier orogenic events have modified the processes of propagation and without an understanding of the existence of such features the propagation processes cannot be fully understood. Furthermore a propagating fault can extend into an active region where it would not have initiated. The North Anatolian Fault encountered slow but active extension when it entered the Aegean about 5 Ma and the stress field associated with the extending fault has progressively modified Aegean extension. In the central Aegean activity has been reduced while to the north-west on features such as the Gulfs of Evvia and Corinth activity has been increased. The field observation that major structures propagate and the success of simple elastic mod- els suggest that the continental crust behaves in an elastic-brittle or elastic-plastic fashion even though laboratory tests may be interpreted to suggest viscous behaviour. There are major prob- lems in scaling from the behaviour of small homogeneous samples to the large heterogeneous mantle and large-scale observations should be treated more seriously than extrapolations of the behaviour of laboratory experiments over many orders of magnitude in space and time. The retention of long-term elasticity and localised failure suggests a similar gross rheology for the oceanic and continental lithospheres. Even though it is incorrect to attribute differences in behaviour to the former being rigid (i.e. elastic) and the latter viscous, oceanic and continental lithosphere behave in different ways. Unlike oceanic crust, continental crust is buoyant and cannot be simply created or destroyed. The process of thickening or thinning works against gravity preventing large displacements on extensional or contractional features in the upper mantle. The equivalents of ridge or subduction systems are suppressed before they can accom- modate large displacements and activity must shift elsewhere. On the other hand, strike-slip boundaries and extrusion processes are favoured. [less ▲]

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See detailFirst paleoseismological constraints on the strongest earthquake in France (Provence) in the twentieth century
Chardon, D.; Hermitte, D.; Nguyen, Frédéric ULg et al

in Geology (2005)

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See detailFirst palynological record of the Silurian/Devonian boundary in the San Juan Precordillera, Argentina
Garcia Muro, V.J.; Rubinstein, C.V.; Steemans, Philippe ULg

Conference (2014)

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See detailFirst pilot trial of the STAR-Liege protocol for tight glycemic control in critically ill patients
Penning, Sophie ULg; Le Compte, Aaron J.; Moorhead, Katherine T. et al

in Computer Methods & Programs in Biomedicine (2011)

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See detailFirst practical implementation of the component method to joints in tubular construction
Weynand, K.; Busse, E.; Jaspart, Jean-Pierre ULg

in Proceedings of the 11th International Symposium on Tubular Structures (2006)

Detailed reference viewed: 51 (0 ULg)