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See detailGravito-inertial and pressure modes detected in the B3 IV CoRoT target HD 43317
Pápics, P. I.; Briquet, Maryline ULg; Baglin, A. et al

in Astronomy and Astrophysics (2012), 542

Context. OB stars are important building blocks of the Universe, but we have only a limited sample of them well understood enough from an asteroseismological point of view to provide feedback on the ... [more ▼]

Context. OB stars are important building blocks of the Universe, but we have only a limited sample of them well understood enough from an asteroseismological point of view to provide feedback on the current evolutionary models. Our study adds one special case to this sample, with more observational constraints than for most of these stars. <BR /> Aims: Our goal is to analyse and interpret the pulsational behaviour of the B3 IV star HD 43317 using the CoRoT light curve along with the ground-based spectroscopy gathered by the HARPS instrument. This way we continue our efforts to map the β Cep and SPB instability strips. <BR /> Methods: We used different techniques to reveal the abundances and fundamental stellar parameters from the newly-obtained high-resolution spectra. We used various time-series analysis tools to explore the nature of variations present in the light curve. We calculated the moments and used the pixel-by-pixel method to look for line profile variations in the high-resolution spectra. <BR /> Results: We find that HD 43317 is a single fast rotator (v[SUB]rot[/SUB] ≈ 50% v[SUB]crit[/SUB]) and hybrid SPB/β Cep-type pulsator with Solar metal abundances. We interpret the variations in photometry and spectroscopy as a result of rotational modulation connected to surface inhomogeneities, combined with the presence of both g and p mode pulsations. We detect a series of ten consecutive frequencies with an almost constant period spacing of 6339 s as well as a second shorter sequence consisting of seven frequencies with a spacing of 6380 s. The dominant frequencies fall in the regime of gravito-inertial modes. The CoRoT space mission was developed and is operated by the French space agency CNES, with participation of ESA's RSSD and Science Programmes, Austria, Belgium, Brazil, Germany, and Spain.Based on data gathered with HARPS installed on the 3.6 m ESO telescope (ESO Large Programme 182.D-0356) at La Silla, Chile.Table A.1 is only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via <A href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/542/A55">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/542/A55</A> [less ▲]

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See detailGravity induced tectonics in charnockitic rocks: the Bjerkreim-Sokndal massif (Rogaland, Southwest Norway)
Bolle, Olivier ULg; Diot, Hervé; Duchesne, Jean-Clair ULg

in Journal of Conference Abstracts (1999), 4

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See detailGravity induced tectonics in the Rogaland anorthositic province, Southwest Norway
Bolle, Olivier ULg; Diot, Hervé; Barnichon, Jean-Dominique et al

in Documents du BRGM (1999), 290

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See detailGravity modes and mixed modes as probes of stellar cores in main-sequence stars: From solar-like to β Cep stars
Miglio, Andrea ULg; Montalban Iglesias, Josefa ULg; Eggenberger, P. et al

in Astronomische Nachrichten (2008), 329

We investigate how the frequencies of gravity modes depend on the detailed properties of the chemical composition gradient that develops near the core of main-sequence stars and, therefore, on the ... [more ▼]

We investigate how the frequencies of gravity modes depend on the detailed properties of the chemical composition gradient that develops near the core of main-sequence stars and, therefore, on the transport processes that are able to modify the \mu profile in the central regions. We show that in main-sequence models, similarly to the case of white dwarfs, the periods of high-order gravity modes are accurately described by a uniform period spacing superposed to an oscillatory component. The periodicity and amplitude of such a component are related, respectively, to the location and sharpness of the \mu gradient. We briefly discuss and interpret, by means of this simple approximation, the effect of turbulent mixing near the core on the periods of both high-order and low-order g modes, as well as of modes of mixed pressure-gravity character. [less ▲]

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See detailGravity modes as a way to distinguish between hydrogen- and helium-burning red giant stars
Bedding, Timothy R; Mosser, Benoit; Huber, Daniel et al

in Nature (2011), 471

Red giants are evolved stars that have exhausted the supply of hydrogen in their cores and instead burn hydrogen in a surrounding shell. Once a red giant is sufficiently evolved, the helium in the core ... [more ▼]

Red giants are evolved stars that have exhausted the supply of hydrogen in their cores and instead burn hydrogen in a surrounding shell. Once a red giant is sufficiently evolved, the helium in the core also undergoes fusion. Outstanding issues in our understanding of red giants include uncertainties in the amount of mass lost at the surface before helium ignition and the amount of internal mixing from rotation and other processes. Progress is hampered by our inability to distinguish between red giants burning helium in the core and those still only burning hydrogen in a shell. Asteroseismology offers a way forward, being a powerful tool for probing the internal structures of stars using their natural oscillation frequencies. Here we report observations of gravity-mode period spacings in red giants that permit a distinction between evolutionary stages to be made. We use high-precision photometry obtained by the Kepler spacecraft over more than a year to measure oscillations in several hundred red giants. We find many stars whose dipole modes show sequences with approximately regular period spacings. These stars fall into two clear groups, allowing us to distinguish unambiguously between hydrogen-shell-burning stars (period spacing mostly ~50seconds) and those that are also burning helium (period spacing ~100 to 300 seconds). [less ▲]

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See detailGravity Score and Shock Score as an Aid to dertemine the prognosis in Equine Surgical Colic Cases
Grulke, Sigrid ULg; Olle, Enrice; Detilleux, Johann ULg et al

in Veterinary Surgery : The Official Journal of the American College of Veterinary Surgeons (1999, July)

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See detailLa gravure à Liège au temps de Lambert Lombard
Warnauts, Samuelle ULg

Scientific conference (2012, February 02)

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See detailGrazing buffalo on flooded pastures in the Brazilian Amazon region: a review
Camarao, A. P.; Lourenco, J. B.; Dutra, S. et al

in Tropical Grasslands (2004), 38(4), 193-203

There are almost 3.5 M head of buffalo in Brazil, half of which (+/- 1.75 M animals) are in the north, particularly on Marajo Island, in the lower and middle Amazon. and on upland cultivated pastures, 16 ... [more ▼]

There are almost 3.5 M head of buffalo in Brazil, half of which (+/- 1.75 M animals) are in the north, particularly on Marajo Island, in the lower and middle Amazon. and on upland cultivated pastures, 16% in the south-cast, 15% in the northeast, 13% in the central west and 6% in the south. The objective of this work was to review the important characteristics of the native pasture ecosystems grazed by buffalo in the flooded areas of the Brazilian Amazon. Data relative to environment, pasture characteristics and animal performance are presented. Three buffalo subspecies, bubalis (water buffalo - Mediterranean. Murrah, Jafarabadi), kerebau (swamp buffalo) and fulvus (Baio type) live in the Amazon Region, their ideal habitat. They are used for meat and milk and as a source of power, and are well adapted to wet conditions. producing and reproducing in flooded native pastures, where cattle don't usually survive. [less ▲]

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See detailGrazing by large river zooplankton: a key to summer potamoplankton decline? The case of the Meuse and Moselle rivers in 1994 and 1995
Gosselain, Véronique; Descy, Jean-Pierre; Viroux, Laurent et al

in Hydrobiologia (1998)

To explain summer declines in phytoplankton biomass in large rivers, we compared the effect of zooplankton grazing on the planktonic algae of two large European rivers, the Meuse and the Moselle. In situ ... [more ▼]

To explain summer declines in phytoplankton biomass in large rivers, we compared the effect of zooplankton grazing on the planktonic algae of two large European rivers, the Meuse and the Moselle. In situ grazing was measured during two years (1994 and 1995), using the Haney method. Total zooplankton community filtration rates recorded in the river Meuse ranged between 1 and 32% of the water volume filtered per day. A drastic algal decline was observed early July both years and may be explained by high densities of a rotiferdominated zooplankton community (500–700 ind. l􀀀1) with more than 75%of Brachionus calyciflorus. During the summer period in 1994, when grazingwas over 20%, edible algal biomasswas controlled by a diversified rotifer community (up to 2500 ind.l􀀀1), while a nonedible algal assemblage developed. In contrast, phytoplankton biomass remained comparatively lowin the Moselle throughout the lowflowperiod, as did zooplankton numbers duringmost of this time (fewer than 200 ind. l􀀀1 during the summer period). The proportion of crustaceans in this zooplanktonwas rather higher than in the Meuse, and they dominated at times, in biomass as well as in numbers. Nevertheless, measured in situ grazing rates (1–15%) could not explain the low summer algal biomass, even if low filtration rates may at times represent a significant carbon loss for phytoplankton, when and where net algal production was low. As a conclusion, the role of phytoplankton – zooplankton interactions in controlling algal biomass in large rivers is discussed. [less ▲]

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See detailLe grazing des bactéries en Méditerranée nord-occidentale
Richir, Jonathan ULg

Master of advanced studies dissertation (2005)

Ces recherches s’intégraient dans un vaste projet de caractérisation des flux biogéophysicochimiques d’un front océanique situé au nord des îles Baléares. Mon travail au sein de ce projet consistait à ... [more ▼]

Ces recherches s’intégraient dans un vaste projet de caractérisation des flux biogéophysicochimiques d’un front océanique situé au nord des îles Baléares. Mon travail au sein de ce projet consistait à mesurer le grazing des bactéries afin de quantifier les transferts de matières et d’énergies vers le niveau trophique supérieur de la boucle microbienne, soit la communauté de protozoaires hétérotrophes. Nos observations nous ont par ailleurs permis de mettre en évidence certains problèmes inhérents à la technique de mesure utilisée, et de les résoudre partiellement. [less ▲]

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See detailGrazing incidence X-ray reflectometry studies of CdTe(1 1 1) surfaces and a-Si thin films
Ijdiyaou, I.; Hafidi, K.; Azizan, M. et al

in Solar Energy Materials & Solar Cells (1998), 52

Chemically treated cadmium telluride (CdTe) surfaces and amorphous silicon (a-Si) thin films were characterized by X-ray reflectometry at grazing incidence. In the case of the surface of CdTe single ... [more ▼]

Chemically treated cadmium telluride (CdTe) surfaces and amorphous silicon (a-Si) thin films were characterized by X-ray reflectometry at grazing incidence. In the case of the surface of CdTe single crystal treated with an oxidizing agent (a solution of Br2 in CH3OH), the superficial layer was found to be less dense than its support with a profound alteration of CdTe in the volume. After rinsing in KOH solution, the properties of single-crystalline CdTe are obtained. In the case of a-Si thin layers, we show that the simulation of the reflectometry curves enables not only the determination of the layer thickness but also the detection of an ultrathin superficial oxide layer. [less ▲]

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See detailGrazing managements with Belgian blue growing bulls before an indoors finishing
Dufrasne, Isabelle ULg; Clinquart, Antoine ULg; Hornick, Jean-Luc ULg et al

in Book of Abstract of the 50th Annual Meeting of the European Association for ANimal Production (1999)

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See detailGRAZING OF BOSMINA LONGIROSTRIS ON TWO PLANKTONIC ALGAE: THE INFLUENCE OF SIZE AND TASTE.
Joaquim-Justo, Célia ULg; Gosselain, V; Descy, Jean-Pierra et al

Poster (1998, August 09)

The cladoceran Bosmina longirostris is a dominant species in the River Meuse (Belgium) especially during summer. Grazing of this small-sized cosmopolitan cladoceran on algae has been stated to be related ... [more ▼]

The cladoceran Bosmina longirostris is a dominant species in the River Meuse (Belgium) especially during summer. Grazing of this small-sized cosmopolitan cladoceran on algae has been stated to be related to the size of the grazed cells by some authors while other studies emphasised on the ability of bosminids to actively capture 'good tasting' particles. Grazing experiments were carried out in the laboratory with B. longirostris feeding on two algal species (Dictyosphaerium ehrenbergianum, 3-4 µm of diameter, and Chlamydomonas reinhardtii, 9-10 µm of diameter). Gut passage times and ingestion rates of the bosminids were determined with radioactively and fluorescently labelled algae. Although both algae have sizes reported to be actively grazed by B. longirostris, they were ingested at very different rates. The relative influence of cell size and cell 'taste' will be discussed. [less ▲]

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See detailGrazing with a mobile milking robot
Dufrasne, Isabelle ULg; Robaye, Vincent ULg; Istasse, Louis ULg et al

in Schnyder, Hans; Isselstein, J.; Taube, F. (Eds.) et al Grassland in a changing world (2010, September)

The size of dairy cow herds in Europe is increasing. Farmers have to manage larger herds but want, at the same time, benefit from a normal social life. So, the milking robot can bring solutions. Its use ... [more ▼]

The size of dairy cow herds in Europe is increasing. Farmers have to manage larger herds but want, at the same time, benefit from a normal social life. So, the milking robot can bring solutions. Its use can reduce physical labour and allow flexibility. During the past 10 years, the number of milking robots has been increased in Europe. In farm practice, this technology has resulted in a reduction in the amount of grazing even though grazing appears as a natural practice which is appreciated by the consumers. At the experimental farm of the University of Liège, we are developing the concept of a mobile milking robot in collaboration with a private company. This prototype will allow cows to graze and could be moved to different locations on pastures during the grazing season. The prototype will be used indoors during the end of the winter season and will be moved outdoor during the 2010 grazing season. The feasibility of this prototype has to be tested in the field. Milk production and quality, the number of visits and the grazing parameters will be recorded. Different equipments in view to attract the cows to the robot as the presence of a cow brush, the location of the drinking point, will be compared. The behaviour of animals will be also assessed. [less ▲]

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See detailGRB 061006: optical afterglow.
Malesani, D.; Stella, L.; D'Avanzo, P. et al

in GRB Coordinates Network (2006), 5718

Not Available

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See detailGRB 070920A: deep optical observations at the NOT.
Jaunsen, A. O.; Gorosabel, J.; Fynbo, J. P. U. et al

in GRB Coordinates Network (2007), 6921

Not Available

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See detailGRB 080315: optical observations.
de Ugarte Postigo, A.; Chantry, Virginie ULg; Castro-Tirado, A. J. et al

E-print/Working paper (2008)

Not Available

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See detailGRB 080319B: optical observations.
Jelinek, M.; Castro-Tirado, A. J.; Chantry, Virginie ULg et al

E-print/Working paper (2008)

Not Available

Detailed reference viewed: 10 (0 ULg)