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Paul Sabatier University

EducationToulouse, 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.


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Journal ArticleDOI
TL;DR: Three major changes allowed us to improve DART accuracy by a factor of three: more accurate simulation of single and multiple scattering, use of a scheme that oversamples DART cells and a better account of the direction of radiation that gives rise to multiple scattered radiation.
Abstract: DART (Discrete Anisotropic Radiative Transfer) is a radiative transfer model that simulates remotely acquired images. It was originally developed to work in the short wavelengths (0.3–3 µm) within 3D natural scenes that are represented as matrices of rectangular cells containing trees, shrubs, grass, soil, etc. DART was recently modified to extend its domain of application and to improve its accuracy. This paper summarizes the major features of DART and presents the changes that were implemented for improving its accuracy. Presently, this model works with natural and urban landscapes, on the whole optical domain (thermal infrared included) and with a multispectral approach that uses optical data bases from 0.3 µm up to 15 µm. It simulates radiative transfer in the whole ‘atmosphere–Earth’ system and it accounts for the instrumental transfer function. Three major changes allowed us to improve DART accuracy by a factor of three: more accurate simulation of single and multiple scattering, use of a scheme tha...

274 citations

Journal ArticleDOI
TL;DR: In this paper, a sample of 28 well-known spectroscopically-identified magnetic Ap/Bp stars, with weak, poorly-determined or previously undetected magnetic fields, was used to explore the weak part of the magnetic field distribution of Ap/bp stars.
Abstract: Aims. We investigated a sample of 28 well-known spectroscopically-identified magnetic Ap/Bp stars, with weak, poorly-determined or previously undetected magnetic fields. The aim of this study is to explore the weak part of the magnetic field distribution of Ap/Bp stars. Methods. Using the MuSiCoS and NARVAL spectropolarimeters at Telescope Bernard Lyot (Observatoire du Pic du Midi, France) and the cross-correlation technique Least Squares Deconvolution (LSD), we obtained 282 LSD Stokes V signatures of our 28 sample stars, in order to detect the magnetic field and to infer its longitudinal component with high precision (median σ = 40 G). Results. For the 28 studied stars, we obtained 27 detections of StokesV Zeeman signatures from the MuSiCoS observations. Detection of the Stokes V signature of the 28th star (HD 32650) was obtained during science demonstration time of the new NARVAL spectropolarimeter at Pic du Midi. This result clearly shows that when observed with sufficient precision, all firmly classified Ap/Bp stars show detectable surface magnetic fields. Furthermore, all detected magnetic fields correspond to longitudinal fields which are significantly greater than some tens of G. To better characterise the surface magnetic field intensities and geometries of the sample, we phased the longitudinal field measurements of each star using new and previously-published rotational periods, and modeled them to infer the dipolar field intensity (Bd, measured at the magnetic pole) and the magnetic obliquity (β). The distribution of derived dipole strengths for these stars exhibits a plateau at about 1 kG, falling off to larger and smaller field strengths. Remarkably, in this sample of stars selected for their presumably weak magnetic fields, we find only 2 stars for which the derived dipole strength is weaker than 300 G. We interpret this “magnetic threshold” as a critical value necessary for the stability of large-scale magnetic fields, and develop a simple quantitative model that is able to approximately reproduce the observed threshold characteristics. This scenario leads to a natural explanation of the small fraction of intermediate-mass magnetic stars. It may also explain the near-absence of magnetic fields in more massive B and O-type stars.

274 citations

Journal ArticleDOI
TL;DR: Previous epidemiological studies have demonstrated a high prevalence of cardiovascular risk factors in psoriasis patients, including metabolic syndrome, cigarette smoking, obesity, hypertension, diabetes mellitus, insulin resistance and dyslipidaemia.
Abstract: Previous epidemiological studies have demonstrated a high prevalence of cardiovascular (CV) risk factors in psoriasis patients, including metabolic syndrome, cigarette smoking, obesity, hypertension, diabetes mellitus, insulin resistance and dyslipidaemia. An increase in CV morbidity and mortality attributable to psoriasis is still under question. Primary objective: to assess CV morbidity and mortality in psoriasis and psoriatic arthritis (PsA) including stroke, coronary artery disease, myocardial infarction (MI) and peripheral artery disease. Secondary objectives: to assess if psoriasis per se is an independent CV risk factor and if psoriasis severity is a predictor of CV risk. We also evaluated the effect of conventional systemic treatments for psoriasis on CV mortality. A systematic literature search was carried out from 1980 to December 2011, in the Embase, Medline and Cochrane Library databases, in English and French using a combination of keywords including (Psoriasis) OR (Psoriatic arthritis) AND (Myocardial infarction) OR (Coronaropathy) OR (Stroke) OR (Cardiovascular) AND (Methotrexate) AND (Ciclosporin) AND (Retinoids). Of the 929 identified references, 33 observational studies evaluating the rates of cardiovascular events (CVE) in patients with psoriasis and PsA compared with controls were selected. Meta-analysis of both cohort and cross-sectional studies showed an increased risk of MI with Odds Ratio (OR) of 1.25 (95% CI 1.03–1.52) and 1.57 (95% CI 1.08–2.27) in psoriasis and PsA, respectively, compared with the general population. The risk of MI was more pronounced for patients having severe psoriasis and for patients with psoriasis of early onset. It remained significantly elevated after controlling for major CV risk factors. The meta-analysis identified a small, but significant association between psoriasis, PsA and coronary artery disease with an OR between 1.19 (95% CI 1.14–1.24) for cross-sectional studies, 1.20 (95% CI 1.13–1.27) for cohort studies and 1.84 (95% CI 1.09–3.09) for case–control studies. The risk of coronary artery disease seemed to be more pronounced in patients with severe psoriasis and in patients with psoriasis of early onset. The meta-analysis assessing the risk of stroke gave inconclusive results: analysis of cross-sectional studies suggested that psoriasis patients had a slightly higher risk of stroke with an OR of 1.14 (95% CI 1.08–1.99), whereas the meta-analysis of cohort studies failed to show an association. There was also an increased risk of peripheral artery disease in psoriasis. No significant increased risk of CV mortality could be shown for both psoriasis and PsA patients. The use of methotrexate was associated with a reduced incidence of cardiovascular disease in two studies. The use of etretinate was associated with a reduction of CV mortality in one study. Potential selection bias such as the ‘healthy user effect’ prevents from drawing definite conclusions. There may be a small, but significant increased risk of CVE, but not of CV mortality in psoriasis and PsA patients. The psoriasis attributable risk remains difficult to assess due to confounding factors. The moderate quality of CV risk factors reporting in studies should be acknowledged. In addition, heterogeneity in study design, outcome definition and assessment represent major limitations. Nevertheless, screening and management of CV risk factors are important in psoriasis.

274 citations

Journal ArticleDOI
29 Jun 2018-Science
TL;DR: Analysis of ancient whole-genome sequences from across Inner Asia and Anatolia shows that the Botai people associated with the earliest horse husbandry derived from a hunter-gatherer population deeply diverged from the Yamnaya, and suggests distinct migrations bringing West Eurasian ancestry into South Asia before and after, but not at the time of, YamNaya culture.
Abstract: The Yamnaya expansions from the western steppe into Europe and Asia during the Early Bronze Age (~3000 BCE) are believed to have brought with them Indo-European languages and possibly horse husbandry. We analyze 74 ancient whole-genome sequences from across Inner Asia and Anatolia and show that the Botai people associated with the earliest horse husbandry derived from a hunter-gatherer population deeply diverged from the Yamnaya. Our results also suggest distinct migrations bringing West Eurasian ancestry into South Asia before and after but not at the time of Yamnaya culture. We find no evidence of steppe ancestry in Bronze Age Anatolia from when Indo-European languages are attested there. Thus, in contrast to Europe, Early Bronze Age Yamnaya-related migrations had limited direct genetic impact in Asia.

273 citations

Journal ArticleDOI
Danaë M. A. Rozendaal, Frans Bongers1, T. Mitchell Aide2, Esteban Álvarez-Dávila, Nataly Ascarrunz, Patricia Balvanera3, Justin M. Becknell4, Tony Vizcarra Bentos5, Pedro H. S. Brancalion6, George A. L. Cabral7, Sofia Calvo-Rodriguez8, Jérôme Chave9, Ricardo Gomes César6, Robin L. Chazdon10, Robin L. Chazdon11, Robin L. Chazdon12, Richard Condit13, Jorn S. Dallinga1, Jarcilene S. Almeida-Cortez7, Ben H. J. de Jong, Alexandre Adalardo de Oliveira6, Julie S. Denslow14, Daisy H. Dent13, Daisy H. Dent15, Saara J. DeWalt16, Juan Manuel Dupuy, Sandra M. Durán8, Lo c Paul Dutrieux1, Lo c Paul Dutrieux17, Mário M. Espírito-Santo, María C. Fandiño, G. Wilson Fernandes18, Bryan Finegan19, Hernando García20, Noel Gonzalez, Vanessa Granda Moser, Jefferson S. Hall13, José Luis Hernández-Stefanoni, Stephen P. Hubbell13, Catarina C. Jakovac21, Catarina C. Jakovac5, Catarina C. Jakovac12, Alma Johanna Hernández20, André Braga Junqueira1, André Braga Junqueira21, André Braga Junqueira12, Deborah K. Kennard22, Denis Larpin, Susan G. Letcher23, Juan Carlos Licona, Edwin Lebrija-Trejos24, Erika Marin-Spiotta25, Miguel Martínez-Ramos3, Paulo Eduardo dos Santos Massoca5, Jorge A. Meave3, Rita C. G. Mesquita5, Francisco Mora3, Sandra Cristina Müller26, Rodrigo Muñoz3, Silvio Nolasco de Oliveira Neto27, Natalia Norden20, Yule Roberta Ferreira Nunes, Susana Ochoa-Gaona, Edgar Ortiz-Malavassi28, Rebecca Ostertag, Marielos Peña-Claros1, Eduardo A. Pérez-García3, Daniel Piotto, Jennifer S. Powers29, José Reinaldo Aguilar-Cano20, Susana Rodríguez-Buriticá20, Jorge Rodríguez-Velázquez3, Marco Antonio Romero-Romero3, Jorge Ruiz30, Jorge Ruiz31, Arturo Sanchez-Azofeifa8, Arlete Silva de Almeida32, Whendee L. Silver33, Naomi B. Schwartz34, William Wayt Thomas35, Marisol Toledo, Ma ia Uríarte34, Everardo Valadares de Sá Barreto Sampaio7, Michiel van Breugel36, Michiel van Breugel37, Michiel van Breugel13, Hans van der Wal38, Sebastião Venâncio Martins27, Maria das Dores Magalhães Veloso, Henricus Franciscus M. Vester39, Alberto Vicentini5, Ima Célia Guimarães Vieira32, Pedro Manuel Villa27, G. Bruce Williamson40, G. Bruce Williamson5, Kátia Janaina Zanini26, Jess K. Zimmerman41, Lourens Poorter1 
TL;DR: This work assesses how tree species richness and composition recover during secondary succession across gradients in environmental conditions and anthropogenic disturbance in an unprecedented multisite analysis for the Neotropics.
Abstract: Old-growth tropical forests harbor an immense diversity of tree species but are rapidly being cleared, while secondary forests that regrow on abandoned agricultural lands increase in extent. We assess how tree species richness and composition recover during secondary succession across gradients in environmental conditions and anthropogenic disturbance in an unprecedented multisite analysis for the Neotropics. Secondary forests recover remarkably fast in species richness but slowly in species composition. Secondary forests take a median time of five decades to recover the species richness of old-growth forest (80% recovery after 20 years) based on rarefaction analysis. Full recovery of species composition takes centuries (only 34% recovery after 20 years). A dual strategy that maintains both old-growth forests and species-rich secondary forests is therefore crucial for biodiversity conservation in human-modified tropical landscapes.

273 citations


Authors

Showing all 15486 results

NameH-indexPapersCitations
Yury Gogotsi171956144520
Tobin J. Marks1591621111604
L. Montier13840397094
Jean-Paul Kneib13880589287
Olivier Forni13754895819
J. Aumont13129995006
Julian I. Schroeder12031550323
Bruno Vellas118101170667
Christopher G. Goetz11665159510
Didier Dubois11374254741
Alain Dufresne11135845904
Henri Prade10891754583
Louis Bernatchez10656835682
Walter Wahli10536549372
Patrice D. Cani10037049523
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Performance
Metrics
No. of papers from the Institution in previous years
YearPapers
202332
202293
2021759
2020753
2019728
2018622