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See detailDeep asteroseismic sounding of the compact hot B subdwarf pulsator KIC02697388 from Kepler time series photometry
Charpinet, Stéphane; Van Grootel, Valérie ULg; Fontaine, Gilles et al

in Astronomy and Astrophysics (2011), 530

Context. Contemporary high precision photometry from space provided by the Kepler and CoRoT satellites generates significant breakthroughs in terms of exploiting the long-period, g-mode pulsating hot B ... [more ▼]

Context. Contemporary high precision photometry from space provided by the Kepler and CoRoT satellites generates significant breakthroughs in terms of exploiting the long-period, g-mode pulsating hot B subdwarf (sdBVs) stars with asteroseismology. Aims: We present a detailed asteroseismic study of the sdBVs star KIC02697388 monitored with Kepler, using the rich pulsation spectrum uncovered during the ~27-day-long exploratory run Q2.3. Methods: We analyse new high-S/N spectroscopy of KIC02697388 using appropriate NLTE model atmospheres to provide accurate atmospheric parameters for this star. We also reanalyse the Kepler light curve using standard prewhitening techniques. On this basis, we apply a forward modelling technique using our latest generation of sdB models. The simultaneous match of the independent periods observed in KIC02697388 with those of models leads objectively to the identification of the pulsation modes and, more importantly, to the determination of some of the parameters of the star. Results: The light curve analysis reveals 43 independent frequencies that can be associated with oscillation modes. All the modulations observed in this star correspond to g-mode pulsations except one high-frequency signal, which is typical of a p-mode oscillation. Although the presence of this p-mode is surprising considering the atmospheric parameters that we derive for this cool sdB star (Teff = 25 395 ± 227 K, log g = 5.500 ± 0.031 (cgs), and log N(He) /N(H) = -2.767 ± 0.122), we show that this mode can be accounted for particularly well by our optimal seismic models, both in terms of frequency match and nonadiabatic properties. The seismic analysis leads us to identify two model solutions that can both account for the observed pulsation properties of KIC02697388. Despite this remaining ambiguity, several key parameters of the star can be derived with stringent constraints, such as its mass, its H-rich envelope mass, its radius, and its luminosity. We derive the properties of the core proposing that it is a relatively young sdB star that has burnt less than ~34% (in mass) of its central helium and has a relatively large mixed He/C/O core. This latter measurement is in line with the trend already uncovered for two other g-mode sdB pulsators analysed with asteroseismology and suggests that extra mixing is occurring quite early in the evolution of He cores on the horizontal branch. Conclusions: Additional monitoring with Kepler of this particularly interesting sdB star should reveal the inner properties of KIC02697388 and provide important information about the mode driving mechanism and the helium core properties. [less ▲]

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See detailDeep Brain Stimulation : une nouvelle thérapie?
Thonnard, Marie ULg

in Schnakers, Caroline; Laureys, Steven (Eds.) Coma et état de conscience altérée (2011)

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See detailDeep brain stimulation for intractable chronic cluster headache: proposals for patient selection
Leone, M.; May, A.; Franzini, A. et al

in Cephalalgia : An International Journal of Headache (2004), 24(11), 934-937

Cluster headache is the most severe of the primary headaches. Positron emission tomography and functional MRI studies have shown that the ipsilateral posterior hypothalamus is activated during cluster ... [more ▼]

Cluster headache is the most severe of the primary headaches. Positron emission tomography and functional MRI studies have shown that the ipsilateral posterior hypothalamus is activated during cluster headache attacks and is structurally asymmetric in these patients. These changes are highly specific for the condition and suggest that the cluster headache generator may be located in that brain area; they further suggest that electrical stimulation of that region might produce clinical improvement in chronic cluster headache sufferers refractory to medical therapy. In five patients with severe intractable chronic cluster headache, hypothalamic electrical stimulation produced complete and long-term pain relief with no relevant side-effects. We therefore consider it essential to propose criteria for selecting chronic cluster headache patients for hypothalamic deep brain stimulation before this procedure is undertaken at other academic medical centres. [less ▲]

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See detailDeep circulation changes in the Labrador sea since the last glacial maximum: New constraints from Sm-Nd data on sediments
Fagel, Nathalie ULg; Innocent, C.; Stevenson, R. K. et al

in Paleoceanography (1999), 14(6), 777-788

Sm-Nd concentrations and Nd isotopes were investigated in the fine fraction of two Labrador Sea cores to reconstruct the deep circulation patterns through changes in sedimentary supply since the last ... [more ▼]

Sm-Nd concentrations and Nd isotopes were investigated in the fine fraction of two Labrador Sea cores to reconstruct the deep circulation patterns through changes in sedimentary supply since the last glacial stage. Three sources are involved: the North American Shield, Palaeozoic rocks from northeastern Greenland, and mid-Atlantic volcanism. The variable input of these sources provides constraints on the relative sedimentary supply, in conjunction with inception of deep currents. During the last glacial stage a persistent but sluggish current occurred inside the Labrador Basin. An increasing discharge of volcanic material driven by the North East Atlantic Deep Water is documented since 14.3 kyr, signaling the setup of a modern-like deep circulation pattern throughout the Labrador, Irminger, and Iceland basins. During the last deglacial stage the isotopic record was punctually influenced by erosion processes related mainly to ice-sheet instabilities, especially 11.4, 10.2, and 9.2 kyr ago. [less ▲]

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See detailDeep drawing process with different elasto-plastic law
de Montleau, P.; Duchene, Laurent ULg; Bouvier, S. et al

in Stören, Sigurd (Ed.) Proceedings of the 7th ESAFORM conference on Material Forming (2004)

Recently, a combination of a texture based yield locus and of the Teodosiu's hardening model has been implemented in the Finite Element code LAGAMINE of the department M&S of the University of Liège. The ... [more ▼]

Recently, a combination of a texture based yield locus and of the Teodosiu's hardening model has been implemented in the Finite Element code LAGAMINE of the department M&S of the University of Liège. The yield locus is able to take into account the texture updating during a FE simulation. The texture evolves with respect to the crystalographic rotations due to the plastic deformations. Two hardening models are considered: the classical Swift istropic hardening model and the Teodosiu's hardening model that is a physically-based microstructural model. It takes into account intergranular heterogeneity due to the evolution of dislocation structures, that affects the isotropic and the kinematic hardening. The aim of the paper is to compare the influence of the hardening with the influence of the yield shape updating due to the texture evolution, on the final plastic anisotropy, for a deep drawing simulation. The tests are performed for the steel FeP06t that presents a non negligible initial anisotropy. [less ▲]

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See detailDeep drawing simulations with different polycrystalline models
Duchene, Laurent ULg; de Montleau, P.; Bouvier, S. et al

in Gosh, Somnath; Castro, Jose M.; Lee, June K. (Eds.) Materials Processing and Design: Modeling, Simulation and Applications (NUMIFORM 2004) (2004)

The goal of this research is to study the anisotropic material behavior during forming processes, represented by both complex yield loci and kinematic-isotropic hardening models. A first part of this ... [more ▼]

The goal of this research is to study the anisotropic material behavior during forming processes, represented by both complex yield loci and kinematic-isotropic hardening models. A first part of this paper describes the main concepts of the ‘Stress-strain interpolation’ model that has been implemented in the non-linear finite element code Lagamine. This model consists of a local description of the yield locus based on the texture of the material through the full constraints Taylor’s model. The texture evolution due to plastic deformations is computed throughout the FEM simulations. This ‘local yield locus’ approach was initially linked to the classical isotropic Swift hardening law. Recently, a more complex hardening model was implemented: the physically-based microstructural model of Teodosiu. It takes into account intergranular heterogeneity due to the evolution of dislocation structures, that affects isotropic and kinematic hardening. The influence of the hardening model is compared to the influence of the texture evolution thanks to deep drawing simulations. [less ▲]

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See detailDeep dysphasia : Further evidence on the relationship between phonological short-term memory and language processing impairments
Majerus, Steve ULg; Lekeu, Françoise ULg; Van der Linden, Martial ULg et al

in Cognitive Neuropsychology (2001), 18(5), 385-410

We report a cognitive investigation of a case of deep dysphasia appearing in the context of primary progressive aphasia. Over a period of 5 years, patient CO presented progressive difficulties in word ... [more ▼]

We report a cognitive investigation of a case of deep dysphasia appearing in the context of primary progressive aphasia. Over a period of 5 years, patient CO presented progressive difficulties in word finding and in oral comprehension, while nonverbal cognitive functions remained preserved. As in other deep dysphasic patients, CO's repetition performance showed marked imageability and lexicality effects, and semantic paraphasias. The same effects were observed in writing-to-dictation. Regularisation errors occurred in word reading. CO's short-term memory span was less than two words. A cognitive analysis of language processing revealed difficulties in phoneme identification and rhyme judgement, in detecting grammatical class for orally presented words, and in oral and written naming. The interpretation of CO's deep dysphasic symptoms within interactive models of language processing confirmed the importance of a phonological short-term storage impairment as an explanatory factor of deep dysphasia. [less ▲]

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See detailDeep freezing of cattle embryos in glass ampules or French straws
Massip, A.; Van der Zwalmen, P.; Ectors, Francis et al

in Theriogenology (1979), 12(2), 79-84

Ninety four cow embryos recovered on day 7-8 after onset of oestrus were frozen by the "Two Step" freezing procedure: 49 in pyrex glass ampules and 45 in .25 ml French semen straws. The overall survival ... [more ▼]

Ninety four cow embryos recovered on day 7-8 after onset of oestrus were frozen by the "Two Step" freezing procedure: 49 in pyrex glass ampules and 45 in .25 ml French semen straws. The overall survival rate was 33.7% (36.2% for embryos frozen in glass ampules; 31.1% for embryos frozen in plastic straws). 45.2% of transferred embryos resulted in pregnancies (35.7% after freezing in glass ampules v.s 52.9% after freezing in plastic straws). [less ▲]

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See detailDeep freezing of cattle embryos in glass ampules or French straws.
Massip, A.; Van der Zwalmen, P.; Ectors, F. et al

in Theriogenology (1979), 12(2), 79-84

Ninety four cow embryos recovered on day 7-8 after onset of oestrus were frozen by the "Two Step" freezing procedure: 49 in pyrex glass ampules and 45 in .25 ml French semen straws. The overall survival ... [more ▼]

Ninety four cow embryos recovered on day 7-8 after onset of oestrus were frozen by the "Two Step" freezing procedure: 49 in pyrex glass ampules and 45 in .25 ml French semen straws. The overall survival rate was 33.7% (36.2% for embryos frozen in glass ampules; 31.1% for embryos frozen in plastic straws). 45.2% of transferred embryos resulted in pregnancies (35.7% after freezing in glass ampules v.s 52.9% after freezing in plastic straws). [less ▲]

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See detailThe Deep Image and Beyond
Delville, Michel ULg

Scientific conference (1999, April 22)

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See detailThe Deep Image
Delville, Michel ULg

in Gray, Jeffrey (Ed.) The Greenwood Encyclopedia of American Poetry (2006)

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See detailDeep Imaging of AX J2019+112: The Luminosity of a ``Dark Cluster''
Benítez, Narciso; Broadhurst, Tom; Rosati, Piero et al

in Astrophysical Journal (1999), 527

We detect a distant cluster of galaxies centered on the QSO lens and luminous X-ray source AX J2019+112, a.k.a. the ``Dark Cluster.'' Using deep V and I Keck images and wide-field K[SUB]s[/SUB] imaging ... [more ▼]

We detect a distant cluster of galaxies centered on the QSO lens and luminous X-ray source AX J2019+112, a.k.a. the ``Dark Cluster.'' Using deep V and I Keck images and wide-field K[SUB]s[/SUB] imaging from the New Technology Telescope (NTT), a tight red sequence of galaxies is identified within a radius of 0.2 h[SUP]-1[/SUP] Mpc of the known z=1.01 elliptical lensing galaxy. The sequence, which includes the central elliptical galaxy, has a slope in good agreement with the model predictions of Kodama et al. for z~1. We estimate the integrated rest-frame luminosity of the cluster to be L[SUB]V[/SUB]>=3.2x10[SUP]11[/SUP] h[SUP]-2[/SUP] L[SUB]solar[/SUB] (after accounting for significant extinction at the low latitude of this field), more than an order of magnitude higher than previous estimates. The central region of the cluster is deconvolved using the technique of Magain, Courbin, & Sohy, revealing a thick central arc coincident with an extended radio source. All the observed lensing features are readily explained by differential magnification of a radio-loud active galactic nucleus by a shallow elliptical potential. The QSO must lie just outside the diamond caustic, producing two images; the arc is a highly magnified image formed from a region close to the center of the host galaxy, projecting inside the caustic. The mass-to-light ratio within an aperture of 0.4 h[SUP]-1[/SUP] Mpc is M[SUB]X[/SUB]/L[SUB]V[/SUB]=224[SUP]+112[/SUP][SUB]- 78[/SUB]h(M/L[SUB]V[/SUB])[SUB]solar[/SUB], using the X-ray temperature. The strong lens model yields a compatible value, M/L[SUB]V[/SUB]=372[SUP]+94[/SUP][SUB]- 94[/SUB]h(M/L[SUB]V[/SUB])[SUB]solar[/SUB], whereas an independent weak-lensing analysis sets an upper limit of M/L[SUB]V[/SUB]<520h(M/L[SUB]V[/SUB])[SUB]solar[/SUB], typical of massive clusters. [less ▲]

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See detailDeep imaging of AXJ2019+112: The luminosity of a ``Dark Cluster''
Benitez, N.; Broadhurst, T.; Rosati, P. et al

in Paul, J.; Montmerle, T.; Aubourg, E. (Eds.) 19th Texas Symposium on Relativistic Astrophysics and Cosmology (1998, December 01)

We detect a distant cluster of galaxies at z ~1 centered on the QSO lens and luminous X-ray source AXJ2019+112 (Hattori et al 1997). The mass-to-light ratio within an aperture of 0.4 h ^{-1}Mpc determined ... [more ▼]

We detect a distant cluster of galaxies at z ~1 centered on the QSO lens and luminous X-ray source AXJ2019+112 (Hattori et al 1997). The mass-to-light ratio within an aperture of 0.4 h ^{-1}Mpc determined using the X-ray temperature is M_x / L_V = 190^{+95}_{-66}h(M/L_V)[SUB]sun[/SUB]. The strong lens model yields a compatible value, M/L_V = 315^{+80}_{-80}h(M/L_V)[SUB]sun[/SUB], whereas an independent weak lensing analysis sets an upper limit of M/L_V < 440 h(M/L_V)[SUB]sun[/SUB]. This confirms that AXJ2019+112 has a M/L ratio similar to that of z < 1 massive clusters. [less ▲]

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See detailDeep Impact at ESO Telescopes
Kaufl, Hans-Ullrich; Ageorges, Nancy; Bagnulo, Stefano et al

in The Messenger (2005), 121

This article is a first summary of the observations done with ESO telescopes and instrumentation in the context of NASA's Deep Impact (DI) space mission. The ESO observers were part of an extremely active ... [more ▼]

This article is a first summary of the observations done with ESO telescopes and instrumentation in the context of NASA's Deep Impact (DI) space mission. The ESO observers were part of an extremely active, communicative and thus successful worldwide network of observers. Through this network all information was freely exchanged and highlights are reported here as well. [less ▲]

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See detailThe deep impact campaign at ESO: the gas component
Rauer, H.; Jehin, Emmanuel ULg; Manfroid, Jean ULg et al

Poster (2005)

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See detailDeep Impact: High-Resolution Optical Spectroscopy with the ESO VLT and the Keck I Telescope
Jehin, Emmanuel ULg; Manfroid, Jean ULg; Hutsemekers, Damien ULg et al

in Astrophysical Journal (2006), 641(Letters), 145-148

We report on observations of comet 9P/Tempel 1 carried out before, during, and after the NASA Deep Impact event (UT July 4), with the optical spectrometers UVES and HIRES mounted on the telescopes Kueyen ... [more ▼]

We report on observations of comet 9P/Tempel 1 carried out before, during, and after the NASA Deep Impact event (UT July 4), with the optical spectrometers UVES and HIRES mounted on the telescopes Kueyen of the ESO VLT (Chile) and Keck I on Mauna Kea (Hawaii), respectively. A total observing time of about 60 hr, distributed over 15 nights around the impact date, allowed us (1) to find a periodic variation of 1.709 +/- 0.009 days in the CN and NH flux, explained by the presence of two major active regions; (2) to derive a lifetime >~5 × 10[SUP]4[/SUP] s (at 1.5 AU) for the parent of the CN radical from a simple modeling of the CN light curve after the impact; (3) to follow the gas and dust spatial profiles' evolution during the 4 hr following the impact and derive the projected velocities (400 and 150 m s[SUP]-1[/SUP], respectively); and (4) to show that the material released by the impact has the same carbon and nitrogen isotopic composition as the surface material ([SUP]12[/SUP]C/[SUP] 13[/SUP]C = 95 +/- 15 and [SUP]14[/SUP]N/[SUP]15[/SUP]N = 145 +/- 20). [less ▲]

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See detailDeep Impact: Observations from a Worldwide Earth-Based Campaign
Meech, K. J.; Ageorges, N.; A'Hearn, M. F. et al

in Science (2005), 310

On 4 July 2005, many observatories around the world and in space observed the collision of Deep Impact with comet 9P/Tempel 1 or its aftermath. This was an unprecedented coordinated observational campaign ... [more ▼]

On 4 July 2005, many observatories around the world and in space observed the collision of Deep Impact with comet 9P/Tempel 1 or its aftermath. This was an unprecedented coordinated observational campaign. These data show that (i) there was new material after impact that was compositionally different from that seen before impact; (ii) the ratio of dust mass to gas mass in the ejecta was much larger than before impact; (iii) the new activity did not last more than a few days, and by 9 July the comet's behavior was indistinguishable from its pre-impact behavior; and (iv) there were interesting transient phenomena that may be correlated with cratering physics. [less ▲]

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