LiDAR-based reference aboveground biomass maps for tropical forests of South Asia and Central Africa

Accurate mapping and monitoring of tropical forests aboveground biomass (AGB) is crucial to design effective carbon emission reduction strategies and improving our understanding of Earth’s carbon cycle. However, existing large-scale maps of tropical forest AGB generated through combinations of Earth Observation (EO) and forest inventory data show markedly divergent estimates, even after accounting for reported uncertainties. To address this, a network of high-quality reference data is needed to calibrate and validate mapping algorithms. This study aims to generate reference AGB datasets using field inventory plots and airborne LiDAR data for eight sites in Central Africa and five sites in South Asia, two regions largely underrepresented in global reference AGB datasets. The study provides access to these reference AGB maps, including uncertainty maps, at 100 m and 40 m spatial resolutions covering a total LiDAR footprint of 1,11,650 ha [ranging from 150 to 40,000 ha at site level]. These maps serve as calibration/validation datasets to improve the accuracy and reliability of AGB mapping for current and upcoming EO missions (viz., GEDI, BIOMASS, and NISAR)

Mobilité d’enfants isolés d’origine camerounaise en Île-de-France : des pratiques traditionnelles locales aux mutations en migration

Dossier 4ème partie : Profils, projets et parcours migratoires des mineurs migrants non accompagnésInternational audienceAu regard du durcissement des politiques d’immigration en vigueur actuellement dans les pays du Nord, on assiste progressivement à une nouvelle forme d’immigration impliquant de plus en plus des mineurs isolés. Alors que ce phénomène concerne majoritairement certains types de pays bien souvent anciennement ancrés de manière institutionnelle ou grâce à la proximité géographique dans les dynamiques migratoires à destination des pays d’accueil, de nouveaux pays d’immigration émergent dans ce champ à l’instar du Cameroun

Méthodologie d'identification des besoins en formation continue des chirurgiens-dentistes (du département du Rhône)

LYON1-BU Santé Odontologie (693882213) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Méthodes analytiques pour le risque des portefeuilles financiers (thèse pour le doctorat en sciences spécialité Mathématiques)

Dans cette thèse, il s'agit d'établir un certains nombre de résultats mathématiques précis concernant l'évaluation de la Valeur a Risque et de l'Expected Shortfall pour un modèle statistique et une composition de portefeuille donnés. On s'intéresse en particulier a la VaR et ES des portefeuilles quadratiques ou linéaires lorsque le vecteur des facteurs de risque suit un mélange de distributions elliptiques. Dans le cas où on traite des portefeuilles quadratiques, nous introduisons une méthode analytique qui consiste a déterminer l'intervalle [V aR-p , V aR+p ] dans lequel la vraie VaR du portefeuille. Contrairement aux méthodes Monte carlo, notre méthode est ultrarapide . En s'inspirant A. Genz (2003), on propose aussi des méthodes numériques pour estimer la VaR des portefeuilles quadratiques, puis on fait des expériences numériques pour illustrer notre démarche. Enfin, on introduit la notion de portefeuilles quadratique de bases (i.e actions)In this PhD thesis, we are concerned by the analytically and numerically estimation for Value-at-Risk and Expected Shortfall for linear or quadratic portfolios with the mixture of elliptically distributed risk factors. As illustration, we provide some explicit estimation of the Value-at-Risk and Expected Shortfall, when the risk factors change with mixture of generalized Laplace distribution or the mixture of t-distributions. Also, some numerical tests have been done, by using dta from CAC 40 french marketREIMS-BU Sciences (514542101) / SudocSudocFranceF

Modeling of radiative heat transfer in a gray semi-transparent medium with internal fluid cavity limited by black boundary surfaces

International audienc

Diagnostic et évolution prénatale de l’ouraque perméable : à propos d’un cas

International audienc

The value of exercise SPET for the detection of coronary artery steal syndrome secondary to unligated major side branch of left internal mammary artery

Objective: The clinical significance of unligated major left internal mammary artery (LIMA)-side branches (SB) remains controversial in patients with previous coronary artery bypass graft (CABG) surgery. The aim of this study was to investigate the clinical significance of unligated major LIMA-SB by using exercise myocardial perfusion imaging (MPI) with single-photon emission tomography. Subjects and Methods: We conducted a retrospective analysis of 2819 consecutive patients who underwent diagnostic angiography. There were 407 CABG patients with LIMA graft. The demographic, laboratory, pre-angiographic stress test and angiographic data of these patients were collected. A subgroup of patients with unligated major LIMA-SB who were referred to angiography with the diagnosis of stable angina pectoris and positive exercise MPI was identified and divided into two groups for comparison: anterior wall vs non-anterior wall ischemia groups. Results: Among 407 patients with LIMA graft, 112 (27.5%) patients were found to have unligated major LIMA-SB. In a subgroup of patients (n=45) with positive exercise MPI and patent LAD-LIMA system with unligated major LIMA-SB, the median values of diameter and length of unligated major LIMA-SB were statistically higher in anterior wall ischemia group (n=24) compared to non-anterior wall ischemia group (1.8mm vs 0.6mm, P= 11.0cm and a diameter of > 1.3cm had 95.8% of sensitivity and 100% of specificity for predicting anterior wall ischemia on exercise MPI. In patients with anterior wall ischemia, summed stress score and summed difference score were improved after percutaneous coil embolization of large unligated major LIMA-SB with 11.0cm length and > 1.3mm diameter. Conclusion: Large unligated major LIMA-SB with 11.0cm length and > 1.3mm diameter seems to be a potential source of ischemia in CABG patients. We suggest that exercise MPI might be a first option noninvasive test in evaluating the clinical significance of unligated major LIMA-SB and the effectiveness of embolization therapy