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See detailBaryon resonances in large N(c) QCD
Matagne, Nicolas; Stancu, Floarea ULg

in Bled Workshops in Physics (2006), 7(1), 61-66

The baryon spectra are discussed in the context of the $1/N_c$ expansion approach, with emphasis on mixed symmetric states. The contributions of the spin dependent terms as a function of the excitation ... [more ▼]

The baryon spectra are discussed in the context of the $1/N_c$ expansion approach, with emphasis on mixed symmetric states. The contributions of the spin dependent terms as a function of the excitation energy are shown explicitly. At large energies these contributions are expected to vanish. [less ▲]

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See detailBaryon to meson transition distribution amplitudes and their spectral representation
Pire, Bernard; Semenov-Tyan-Shanskiy, Kirill ULg; Szymanowski, Lech

in AIP Conference Proceedings (2010), 1350

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See detailBaryon vector and axial content up to the 7Q component
Lorce, Cédric ULg

in Physical Review. D, Particles, Fields, Gravitation, and Cosmology (2008), D78

We have used the light-cone formulation of the chiral-quark soliton model to investigate the vector and axial content of octet, decuplet, and hypothetical antidecuplet in the flavor $SU(3)$ symmetry limit ... [more ▼]

We have used the light-cone formulation of the chiral-quark soliton model to investigate the vector and axial content of octet, decuplet, and hypothetical antidecuplet in the flavor $SU(3)$ symmetry limit. We have extended previous works by computing the 7Q contribution to vector and axial charges for the octet and antidecuplet but stayed at the 5Q sector for the decuplet where the full computation needs much more time. As expected, the 7Q component has a weaker impact on the quantities but still changes them by a few percent. We give also a detailed decomposition of those charges into flavor, valence quark, sea quark, and antiquark contributions. Many of them are of course not (yet) measured or estimated and constitute then a theoretical estimation. Among the different interesting observations made in this work are the explicit quadrupole deformation of decuplet baryons due to the pion field and the sum of quark spins larger than the pentaquark one. [less ▲]

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See detailBaryonic mass formula in large N-c QCD versus quark model
Semay, C.; Buisseret, F.; Matagne, Nicolas et al

in Physical Review D (2007), 75(9),

We establish a connection between the quark model results and the 1/N-c expansion mass formula used in the description of baryon resonances. We show that a remarkable compatibility exists between the two ... [more ▼]

We establish a connection between the quark model results and the 1/N-c expansion mass formula used in the description of baryon resonances. We show that a remarkable compatibility exists between the two methods. [less ▲]

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See detailBasal and postexercise CK 2 concentrations in a group of well trained athletes evaluated by chemiluminescent assay
Ordonez, J.; Chapelle, Jean-Paul ULg; Serra, J. R. et al

Poster (1990, October)

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See detailA basal thunnosaurian from Iraq reveals disparate phylogenetic origins for Cretaceous ichthyosaurs
Naish, Darren; Fischer, Valentin ULg; Liston, Jeff et al

Poster (2013, October)

A new thunnosaurian from the Kurdistan region of Iraq represents the first post-Triassic ichthyosaur from the Middle East. The specimen is an articulated partial skeleton that includes a partial skull ... [more ▼]

A new thunnosaurian from the Kurdistan region of Iraq represents the first post-Triassic ichthyosaur from the Middle East. The specimen is an articulated partial skeleton that includes a partial skull, complete left forefin, partial ribcage and anterior section of the vertebral column. Associated palynomorphs uncontroversially date the specimen (preserved on a loose slab of matrix) to the late Hauterivian- Barremian interval of the Early Cretaceous. A posterior projection on the humerus, short and trapezoidal humerus, enlarged intermedium, and trapezoidal cervical and anterior dorsal neural spines represent autapomorphies. Forefin morphology is archaic: the carpals, metacarpals and phalanges form a mosaic similar to that of Triassic-Early Jurassic parvipelvians, accessory digits are absent, and notching is present on the leading edge of the first digit. These and other characters indicate exclusion of the Iraq ichthyosaur from Ophthalmosauridae, the only ichthyosaur clade currently known from the Cretaceous. A phylogenetic analysis of Parvipelvia – the largest yet produced – recovers the new taxon as the sister- taxon of Ichthyosaurus communis, thereby invoking a ghost-lineage of over 60 million years. Inclusion of the new taxon in analyses produced by other authors also resulted in exclusion from Ophthalmosauridae, though relationships with other neoichthyosaurians are less resolved than in our analysis. We conclude that the new taxon represents a highly conservative relict – a member of the Ichthyosaurus lineage – that retained an ‘Early Jurassic’ grade of pectoral anatomy into the Cretaceous. Ophthalmosauridae and members of the Ichthyosaurus lineage therefore both persisted beyond the Jurassic. Clearly, both have highly contrasting evolutionary histories and Cretaceous ichthyosaurs do not all represent members of the same evolutionary radiation. The Iraq ichthyosaur is one of several new taxa originally worked on by the late Robert M. Appleby. An inability to resolve conflicting views on the age of the specimen, combined with other issues, derailed his plans to publish on this specimen during the 1970s. [less ▲]

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See detailA basal thunnosaurian from Iraq reveals disparate phylogenetic origins for Cretaceous ichthyosaurs
Fischer, Valentin ULg; Appleby, Robert; Naish, Darren et al

in Biology Letters (2013), 9(20130021), 1-6

Cretaceous ichthyosaurs have typically been considered a small, homogeneous assemblage sharing a common Late Jurassic ancestor. Their low diversity and disparity have been interpreted as indicative of a ... [more ▼]

Cretaceous ichthyosaurs have typically been considered a small, homogeneous assemblage sharing a common Late Jurassic ancestor. Their low diversity and disparity have been interpreted as indicative of a decline leading to their Cenomanian extinction. We describe the first post-Triassic ichthyosaur from the Middle East, Malawania anachronus gen. et sp. nov. from the Early Cretaceous of Iraq, and re-evaluate the evolutionary history of parvipelvian ichthyosaurs via phylogenetic and cladogenesis rate analyses. Malawania represents a basal grade in thunnosaurian evolution that arose during a major Late Triassic radiation event and was previously thought to have gone extinct during the Early Jurassic. Its pectoral morphology appears surprisingly archaic, retaining a forefin architecture similar to that of its Early Jurassic relatives. After the initial latest Triassic radiation of early thunnosaurians, two subsequent large radiations produced lineages with Cretaceous representatives, but the radiation events themselves are pre-Cretaceous. Cretaceous ichthyosaurs therefore include distantly related lineages, with contrasting evolutionary histories, and appear more diverse and disparate than previously supposed. [less ▲]

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See detailBasalt weathering laws and the impact of basalt weathering on the global carbon cycle
Dessert, C.; Dupre, B.; Gaillardet, J. et al

in Chemical Geology (2003), 202(3-4), 257-273

This study attempts to characterise the chemical weathering of basalts and to quantify the flux of carbon transferred from the atmosphere to the ocean during this major process at the surface of the Earth ... [more ▼]

This study attempts to characterise the chemical weathering of basalts and to quantify the flux of carbon transferred from the atmosphere to the ocean during this major process at the surface of the Earth. To this aim, we have compiled different published chemical compositions of small rivers draining basalts. Basaltic river waters are characterised by relatively high Na-normalized molar ratios (Ca/Na: 0.2-3.9; HCO3/Na: 1-10; Mg/Na: 0.15-6) in comparison with those usually observed for river draining silicates. The data also show the climatic influence on basalt weathering and associated CO2 consumption. Runoff and temperature are the main parameters controlling the chemical weathering rate and derived CO2 consumption during basaltic weathering. From these relationships and digital maps, we are able to define the contribution of basalts to the global silicate flux. Taking account of this result, we estimate that the CO2 flux consumed by chemical weathering of basalts is about 4.08 x 10(12) mol/year. The fluxes from the islands of Indonesia and regions of central America represent around 40% of this flux. The global flux of CO2 consumed by chemical weathering of basalts represents between 30% and 35% of the flux derived from continental silicate determined by Gaillardet et al. [Chem. Geol. 159 (1999) 3]. Finally, it appears that volcanic activity not only acts as a major atmospheric CO2 source, but also creates strong CO2 sinks that cannot be neglected to better understand the geochemical and climatic evolution of the Earth. (C) 2003 Elsevier B.V. All rights reserved. [less ▲]

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See detailBasaltic volcanism and mass extinction at the Permo-Triassic boundary: Environmental impact and modeling of the global carbon cycle
Grard, Aline ULg; François, Louis ULg; Dessert, C. et al

in Earth And Planetary Science Letters (2005), 234(1-2), 207-221

The Siberian Traps represent one of the most voluminous continental flood basalt provinces on Earth. The mass extinction at the end of the Permian was the most severe in the history of life. In the ... [more ▼]

The Siberian Traps represent one of the most voluminous continental flood basalt provinces on Earth. The mass extinction at the end of the Permian was the most severe in the history of life. In the present paper, these two major concurrent events that occurred are analysed and a geochemical model coupled with an energy balance model is used to calculate their environmental impact on atmospheric CO2, oceanic delta(13)C, and marine anoxia. The latitudinal temperature gradient is reduced relative to today, resulting in warmer temperatures at high latitudes. The warmer climate and the presence of fresh basaltic provinces increase the weatherability of the continental surfaces, resulting in an enhanced consumption of atmospheric CO2 through weathering. First, the eruption of the Siberian traps is accompanied by a massive volume of C-13 depleted CO2 degassed from the mantle and added to the ocean through silicate weathering, thus lowering marine delta(13)C. Second, the rapid collapse in productivity induces a strong decrease in the global organic carbon burial. This too tends to increase the proportion of light carbon in the ocean. These two effects can explain the low delta(13)C values across the PT boundary, and methane release need not be invoked to explain the delta(13)C fluctuations. It is proposed that the phosphorus cycle, which drives primary production in the model, plays an important role on the recovery of productivity and the delta(13)C variations. (c) 2005 Elsevier B.V All rights reserved. [less ▲]

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See detailBase de calcul pour le dimensionnement d'une tour de refroidissement à tirage naturel
Nicolas, Jacques ULg; Vasel, Jean-Luc ULg

in European Journal of Mechanical and Environmental Engineering (1992), 37

Le but de cet article est de fournir de façon exhaustive l'ensemble des relations qui permettent le calcul des transferts thermiques dans une tour de refroidissemenmt à contrecourant et à tirage naturel ... [more ▼]

Le but de cet article est de fournir de façon exhaustive l'ensemble des relations qui permettent le calcul des transferts thermiques dans une tour de refroidissemenmt à contrecourant et à tirage naturel. L'article se base sur les approches classiques décrites dans la littérature (Merkel, Chilton, Braun, ...), mais en uniformisant les symboles et les unités, de façon à fournir en un seul texte tous les éléments qui permettent de modéliser, pour des besoins de contrôle ou de dimensionnement, une tour de refroidissement et d'en estimer les performances.Quelques pratiques d'utilisation de ces relations sont étudiées, ainsi qu'une confrontation de différentes méthodes de résolution sur un même exemple. [less ▲]

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See detailBase de données des relevés phytosociologiques
Dufrêne, Marc ULg

Textual, factual or bibliographical database (2012)

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See detailLa base de données du CIEL
Dozo, Björn-Olav ULg; Vanderpelen, Cécile

Conference (2008, December 04)

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See detailBase de données du Collectif interuniversitaire d'étude du littéraire (CIEL)
Dozo, Björn-Olav ULg; CIEL (Collectif interuniversitaire d'étude du littéraire)

Textual, factual or bibliographical database (2009)

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See detailBase de données mortalité et étude du régime alimentaire (Balbuzard)
Rosoux, René; Libois, Roland ULg; Schweyer, Jean Baptiste

Learning material (2010)

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See detailBase de données PMI - stratégie, exportation, innovation
Choffray, Jean-Marie ULg; Pras, Bernard; Roux, Elyette

Book published by FNEGE/ESSEC (1994)

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See detailBase de données sols de REQUASUD - 3ème synthèse
Genot, Valérie ULg; Renneson, Malorie ULg; Colinet, Gilles ULg et al

Book published by ASBL REQUASUD - D/2012/8689/1 (2012)

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See detailBase de données sur les métiers du livre au Québec
Dozo, Björn-Olav ULg; Melançon, François; GRÉLQ (Groupe de recherche sur l'édition littéraire au Québec)

Textual, factual or bibliographical database (2010)

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See detailBase de données sur les prix artistiques dans l'entre-deux-guerres au Québec
Dozo, Björn-Olav ULg; Lapointe, Olivier

Textual, factual or bibliographical database (2008)

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