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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)

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See detailFirst principle study of nanodiamond optical and electronic properties
Raty, Jean-Yves ULg; Galli, G.

in Computer Physics Communications (2005), 169(1-3), 14-1919

Nanometer sized diamond has been found in meteorites, proto-planetary nebulae and interstellar dusts, as well as in residues of detonation and in diamond films. Remarkably, the size distribution of ... [more ▼]

Nanometer sized diamond has been found in meteorites, proto-planetary nebulae and interstellar dusts, as well as in residues of detonation and in diamond films. Remarkably, the size distribution of diamond nanoparticles appears to be peaked around 2-5 nm, and to be largely independent of preparation conditions. Using ab-initio calculations, we have shown that in this size range nanodiamond has a fullerene-like surface and, unlike silicon and germanium, exhibits very weak quantum confinement effects. We called these carbon nanoparticles bucky-diamonds: their atomic structure, predicted by simulations, is consistent with many experimental findings. In addition, we carried out calculations of the stability of nanodiamond, which provided a unifying explanation of its size distribution in extra-terrestrial samples, and in ultra-nano crystalline diamond (UNCD) films. [All rights reserved Elsevier] [less ▲]

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See detailFirst Principles Explanation of the Positive Seebeck Coefficient of Lithium
Xu, Bin ULg; Verstraete, Matthieu ULg

in Physical Review Letters (2014), 112

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See detailFirst Principles Study of the lattice instabilities in BaxSr1-xTiO3
Ghosez, Philippe ULg; Desquesnes, D.; Gonze, X. et al

in AIP Conference Proceedings (2000), 535

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See detailFirst prototypes of vortex retarders obtained by polarization holography
Piron, Pierre ULg; Blain, Pascal ULg; Décultot, Marc ULg et al

in Proceedings of SPIE (2014, May), 9099

This paper will present the first prototypes of vortex retarders made of photo-orientable liquid crystals polymers recorded without mechanical action using only polarization holography. Vortex retarders ... [more ▼]

This paper will present the first prototypes of vortex retarders made of photo-orientable liquid crystals polymers recorded without mechanical action using only polarization holography. Vortex retarders are birefringent plates characterized by a uniform phase retard and a rotation of their fast axis along their center. Liquid crystals are anisotropic molecules possessing birefringent properties. They are locally orientable and their orientation defines the fast axis orientation of the retarder. Their alignment depends on the local orientation of the recording electric field. The superimposition of several polarized beams will be used to shape the electric field to achieve the recording of vortex retarders. The mathematical aspects of the superimposition process, as well as several numerical simulations are exposed. Finally, the first prototypes are presented, characterized and compared to the numerical simulations. [less ▲]

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See detailFirst record of Demosponge spicules in a late Devonian stromatoporoid basal skeleton (Frasnian, Belgium).
Reitner; Da Silva, Anne-Christine ULg; Kershaw et al

in Abstracts: Ninth world sponge conference 2013 (2013)

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See detailFirst record of Rellimia Leclercq & Bonamo (Aneurophytales) from Gondwana, with comments on the earliest lignophytes.
Gerrienne, Philippe ULg; Meyer-Berthaud, Brigitte; Lardeux, Hubert et al

in Special Publication - Geological Society of London (2010), 339

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See detailFirst record of the 'bathroom mothmidge' Clogmia albipunctata, a conspicuous element of the Belgian fauna that went unnoticed (Diptera: Psychodidae)
Boumans, Louis; Zimmer, Jean-Yves ULg; Verheggen, François ULg

in Phegea (2009), 37(4), 153-160

The 'bathroom fly' Clogmia albipunctata (Williston, 1893) (Diptera: Psychodidae) is a cosmopolitan species that is commonly found in bathrooms, kitchens, sewage treatment plants and compost heaps. Of ... [more ▼]

The 'bathroom fly' Clogmia albipunctata (Williston, 1893) (Diptera: Psychodidae) is a cosmopolitan species that is commonly found in bathrooms, kitchens, sewage treatment plants and compost heaps. Of circumtropical origin, the species probably spread to synanthropic habitats in northern and central Europe during the past decades. The first documented findings in Belgium are discussed, together with general information on the biology and recognition of the species. [less ▲]

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