Institution
Paul Sabatier University
Education•Toulouse, France•
About: Paul Sabatier University is a education organization based out in Toulouse, France. It is known for research contribution in the topics: Population & Adipose tissue. The organization has 15431 authors who have published 23386 publications receiving 858364 citations.
Papers published on a yearly basis
Papers
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TL;DR: In this paper, the authors considered a new model of individual displacement, based on fish motion, the so-called persistent turning Walker (PTW) model, which involves an Ornstein-Uhlenbeck process on the curvature of the particle trajectory.
Abstract: This paper considers a new model of individual displacement, based on fish motion, the so-called Persistent Turning Walker (PTW) model, which involves an Ornstein-Uhlenbeck process on the curvature of the particle trajectory. The goal is to show that its large time and space scale dynamics is of diffusive type, and to provide an analytic expression of the diffusion coefficient. Two methods are investigated. In the first one, we compute the large time asymptotics of the variance of the individual stochastic trajectories. The second method is based on a diffusion approximation of the kinetic formulation of these stochastic trajectories. The kinetic model is a Fokker-Planck type equation posed in an extended phase-space involving the curvature among the kinetic variables. We show that both methods lead to the same value of the diffusion constant. We present some numerical simulations to illustrate the theoretical results.
164 citations
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TL;DR: The Eastern Nigeria terrane belongs to the 3000 km-long Trans-Saharan belt which was formed in the Neoproterozoic, between 750 and 500 Ma by continental collision between the converging West African craton, Congo craton and East Saharan block as discussed by the authors.
164 citations
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University of Bologna1, INAF2, University of Geneva3, Paul Sabatier University4, European Southern Observatory5, University of Edinburgh6, University of Provence7, Max Planck Society8, University of Nottingham9, University of Hawaii10, Institut d'Astrophysique de Paris11, Jagiellonian University12, University of California, San Diego13, University of Porto14, University of Milan15
TL;DR: In this article, the optical luminosity function up to z = 3.6 was derived from the first epoch data of the VIMOS-VLT Deep Survey (VVDS) and compared with previous results from brighter samples both at low and at high redshift.
Abstract: In a previous paper (Gavignaud et al. 2006), we presented the type-1 Active Galactic Nuclei (AGN) sample obtained from the first epoch data of the VIMOS-VLT Deep Survey (VVDS). The sample consists of 130 faint, broad-line AGN with redshift up to z=5 and 17.5< I <24.0, selected on the basis of their spectra. In this paper we present the measurement of the Optical Luminosity Function up to z=3.6 derived from this sample, we compare our results with previous results from brighter samples both at low and at high redshift. Our data, more than one magnitude fainter than previous optical surveys, allow us to constrain the faint part of the luminosity function up to high redshift. By combining our faint VVDS sample with the large sample of bright AGN extracted from the SDSS DR3 (Richards et al., 2006b) and testing a number of different evolutionary models, we find that the model which better represents the combined luminosity functions, over a wide range of redshift and luminosity, is a luminosity dependent density evolution (LDDE) model, similar to those derived from the major X-surveys. Such a parameterization allows the redshift of the AGN space density peak to change as a function of luminosity and explains the excess of faint AGN that we find at 1.0< z <1.5. On the basis of this model we find, for the first time from the analysis of optically selected samples, that the peak of the AGN space density shifts significantly towards lower redshift going to lower luminosity objects. This result, already found in a number of X-ray selected samples of AGN, is consistent with a scenario of "AGN cosmic downsizing", in which the density of more luminous AGN, possibly associated to more massive black holes, peaks earlier in the history of the Universe, than that of low luminosity ones.
164 citations
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TL;DR: In this article, the stochastic properties of As (III) hydroxide complexes were determined from both solubility and Raman spectroscopic measurements, and it was shown that H3AsO30(aq) is the dominant As-bearing species at concentrations up to ~1 m over a wide range of pH (0-8) and temperature (20-300 °C).
164 citations
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TL;DR: The world pattern of functional diversity of freshwater fish using a database encompassing morphological characteristics of more than 9,000 species shows the Neotropical realm hosts more than 75% of global functional diversity while other realms each host less than 25%.
Abstract: Worldwide biodiversity assessments have mainly focused on species richness but little is known about the diversity of species roles, i.e. functional diversity, while this is a key facet to understanding the consequences of global changes on the ecosystem services to human societies. Here, we report the world pattern of functional diversity of freshwater fish using a database encompassing morphological characteristics of more than 9,000 species. The Neotropical realm hosts more than 75% of global functional diversity while other realms each host less than 25%. This discrepancy is mediated by high functional uniqueness in some diversified Neotropical fish orders. Surprisingly, functional diversity patterns were weakly related to functional vulnerability. In the Neotropics the loss of threatened species will cause a limited loss of functional diversity (<10%) whereas in the Nearctic and Palearctic realms, decline of the functional diversity will reach 43% and 33%, respectively, conferring a high functional vulnerability to these realms. Conservation of the Neotropical fish diversity is a key target to maintain world fish functional diversity, but this should not hide the pressing need to conserve the vulnerable fish faunas of the rest of the world, in which functional diversity is to a large extent supported by threatened species.
164 citations
Authors
Showing all 15486 results
Name | H-index | Papers | Citations |
---|---|---|---|
Yury Gogotsi | 171 | 956 | 144520 |
Tobin J. Marks | 159 | 1621 | 111604 |
L. Montier | 138 | 403 | 97094 |
Jean-Paul Kneib | 138 | 805 | 89287 |
Olivier Forni | 137 | 548 | 95819 |
J. Aumont | 131 | 299 | 95006 |
Julian I. Schroeder | 120 | 315 | 50323 |
Bruno Vellas | 118 | 1011 | 70667 |
Christopher G. Goetz | 116 | 651 | 59510 |
Didier Dubois | 113 | 742 | 54741 |
Alain Dufresne | 111 | 358 | 45904 |
Henri Prade | 108 | 917 | 54583 |
Louis Bernatchez | 106 | 568 | 35682 |
Walter Wahli | 105 | 365 | 49372 |
Patrice D. Cani | 100 | 370 | 49523 |