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Rapport de l'équipe française du projet ANR "Financing Clean Air", sur les potentialités de la Land Value Capture pour financer des infrastructures ferroviaires
No full textTo co-finance costly metro networks intended to reduce urban pollution, public authorities are increasingly turning to land value capture (LVC) instruments. This project examines the socio-economic and urban challenges associated with these policies and asks to what extent co-financing metro networks through LVC mechanisms contributes to sustainable urban development.The research forms part of the Sino-European project Financing Clean Air, led by colleagues at the University of Liverpool and involving researchers from four countries (France, the Netherlands, England, and China). The project aimed to explore the potential of LVC mechanisms to co-finance climate change adaptation measures in order to enhance the economic, social, and environmental sustainability of cities. LVC refers to the practice of capturing all or part of the increase in land value generated by public investment and not attributable to the efforts of landowners or property owners.Our two French project sub-teams (Géographie-cités/Paris 1 Panthéon Sorbonne and LabUrba/Université Créteil-Val de Marne) focused on the use of LVC to co-finance metro networks, with particular attention to Paris (Grand Paris Express) and London, as well as cases in China (Shenzhen and Nanjing) and the Netherlands. The objectives were to characterize the different LVC mechanisms, examine how they are appropriated by public and private actors (including rail operators), and analyze their effects on both the distribution of extracted land rents and the characteristics of the urban materiality produced.The research adopted a qualitative methodology based on semi-structured interviews with a wide range of stakeholders (state representatives, developers, planners, local authorities, consulting firms, etc.), complemented by an analysis of press articles and institutional and professional publications. The investigation also drew on research conducted within Master’s and PhD programs in urban planning at Paris 1 Panthéon-Sorbonne and Université Paris-Créteil-Val de Marne.Pour cofinancer les coûteux réseaux de métro appelés à réduire la pollution urbaine, les autorités publiques se tournent de plus en plus vers des outils de LVC consistant à extraire la rente foncière. Notre projet explore les enjeux socio-économiques et urbains de ces politiques. Dans quelle mesure le cofinancement des réseaux de métro par des mécanismes de LVC contribue-t-il à un développement urbain durable ? Cette recherche entre dans le cadre du projet sino-européen « Financing Clean Air » dirigé par des collègues de l'Université de Liverpool et réunissant des chercheurs de quatre pays (France, Pays-Bas, Angleterre et Chine). L'objectif était d'explorer le potentiel des mécanismes de captation des plus-values foncières (Land Value Capture, LVC) pour cofinancer les adaptations au changement climatique, afin d'assurer une plus grande durabilité économique, sociale et environnementale des villes. La pratique de LVC consiste à capter tout ou partie de l'accroissement de la valeur foncière résultant de l'investissement public et non imputable aux efforts des propriétaires fonciers/immobiliers. Nos deux sous-équipes françaises du projet (Géographie-cités/Paris 1 Panthéon Sorbonne et LabUrba/Université Créteil-Val de Marne) se sont focalisées sur les usages de la LVC pour le cofinancement des réseaux de métro, en particulier à Paris (Grand Paris Express) et à Londres, mais également en Chine (Shenzhen et Nanjing) et aux Pays-Bas. Il s'agissait de caractériser les différents mécanismes de LVC, d'étudier leur appropriation par les acteurs publics et privés (dont notamment les opérateurs ferroviaires), et d'analyser leurs effets sur le partage de la rente foncière extraite ainsi que sur les caractéristiques de la matérialité urbaine produite. La recherche a été menée selon une méthodologie qualitative, basée sur des entretiens semi-structurés avec une grande diversité d'acteurs (État, promoteurs, aménageurs, collectivités locales, bureaux d'étude…), complétés par l'analyse d'articles de presse, de publications institutionnelles et professionnelles. Le travail d'enquête s'est appuyé en partie sur des recherches menées dans le cadre de Masters d'urbanisme et de thèses à l'université Paris 1 Panthéon-Sorbonne et à l'université Paris-Créteil-Val de Marne
Impact of lymph node staging on survival in presumed early-stage ovarian cancer: a multicentric retrospective study
No full textInternational audienceObjective:This study aimed to assess the impact of comprehensive staging on survival outcomes in this population.Methods:Patients who underwent surgery for epithelial ovarian cancer in one of the 14 Francogyn cancer centers between 2000 and 2020 were included in the study. The primary analysis evaluated the impact of lymphadenectomy on overall survival and recurrence-free survival. Lymph node count was analyzed as a continuous variable, and its association with survival, considered as a continuous outcome was assessed using linear regression (secondary analysis). Survival was compared using the log-rank test, and multivariate analysis was performed using a Cox model.Results:A total of 467 patients with presumed early-stage epithelial ovarian cancer were included, of which 198 underwent complete lymphadenectomy and 266 did not. No significant association was found between lymph node staging and survival in the primary analysis, possibly due to limited statistical power and a selection bias, as patients without lymphadenectomy had more favorable disease profiles (p=0.600 and p=0.700, respectively). Complete lymphadenectomy was associated with a significantly higher risk of complications (34.5% vs. 14%, p<0.001). In secondary analysis, the number of para-aortic lymph nodes harvested was identified as an independent predictor of both overall survival and recurrence-free survival (p=0.007 and p=0.002, respectively). Histological characteristics and adjuvant chemotherapy also showed a significant correlation with improved survival outcomes.Conclusion:Extensive para-aortic lymphadenectomy in early-stage epithelial ovarian cancer is associated with better overall and recurrence-free survival but comes with an increased risk of complications
Sampling methods for probabilistic approximations of ODEs
No full textExtended abstract accepted for presentation at ROADEF 2026.Ordinary Differential Equations (ODEs) are used to model dynamical systems, notably inbiology and biochemistry. In such systems, the estimation of parameters from experimentaldata is a central challenge, with applications such as drug discovery or clinical diagnosis. Liu B. et al. proposed to transform ODEs into Dynamic Bayesian Networks (DBNs) [1] tospeed up cost function calculations, limit repeated ODEs simulations, and quantify the uncer-tainty on states and parameters, obtaining better results than classical optimization techniquesfor systems with less than ≈ 25 variables.The construction of a DBN requires to discretize the state space and generate a trainingdata set (a set of many ODEs simulations) to fill the Conditional Probability Tables (CPTs).Low-discrepancy sequences, like those of Halton [2], used previously [3], do not guarantee goodcoverage of discrete intervals [4], certain regions of space being under-represented, as can beseen in Figure 1. This can bias the tables of the DBN and affect the quality of the probabilisticapproximation.In this paper, we propose a structured enumerative sequence ensuring uniform coverage ofdiscrete intervals, allowing more representative tables and a better probabilistic approximationof the dynamic system by the DBN
Transgenerational effects of a high temperature impair the resistance of the pest Spodoptera frugiperda to a parasitoid
No full textInternational audienceInsect parasitoids provide a useful ecosystem service to control pest insects. However, climate change could challenge this pest management, as insects are known to be sensitive to temperature. Furthermore, transgenerational effects, which are common in insects, could influence these effects of temperature on host-parasitoid systems. The present study therefore aimed to test the combined effects of developmental and host parental temperatures on a host-parasitoid system, using the fall armyworm (FAW) and the parasitoid Hyposoter didymator. We focused on mean temperatures of 25 and 29 °C, with a daily fluctuation of ±5 °C. The increase in mean temperatures had a significant effect on all the host parameters tested (survival, developmental rate, sex ratio, body mass) and on parasitoid success. Parasitoid success decreased between the developmental temperatures of 25 and 29 °C, and most effects of the increase in developmental temperature on FAW traits were detrimental to the parasitoid. Remarkably, we found transgenerational effects of temperature on the host resistance to parasitoids (the proportion of FAW escaping parasitism), as well as on host traits associated with the probability of parasitoids finding a host (effects on survival and developmental rates) and host quality (body mass, sex ratio). The parental temperature of 29 °C had a detrimental effect on the FAW resistance to parasitoids, but it reinforced the effects of developmental temperature on host traits that have a negative impact on parasitoids. The study shows the high thermal sensitivity of a host-parasitoid system and highlights that thermal transgenerational plasticity should be considered in host-parasitoid interactions
Target trial emulation to replicate randomised clinical trials using registry data in multiple sclerosis
No full textInternational audienceBackground: Target trial emulation (TTE) offers a formal framework for causal inference using observational data, but its validity must be evaluated in each research domain by replicating randomised clinical trials (RCTs). We aimed to replicate eight RCTs evaluating the efficacy of disease-modifying therapies (DMTs) in multiple sclerosis (MS) using French registry data.Methods: This multicentre, retrospective, observational study was conducted using data extracted in December 2023 from the Observatoire Français de la Sclérose en Plaques (OFSEP) database. For each emulated trial, patients were included when they initiated one of the DMT evaluated in the corresponding RCT and met its inclusion criteria. Clinical outcomes were the annualised relapse rate and 3-month confirmed Expanded Disability Status Scale progression. Radiological outcomes were new/enlarged T2-lesions and new gadolinium-enhanced T1-lesions on a brain MRI. A targeted maximum likelihood estimator was used to estimate the treatment effect adjusted for confounding factors between groups and corrected for censoring and missing outcome assessment.Results: 14 111 patients were included in eight emulated trials: ASSESS (fingolimod vs glatiramer acetate), BEYOND (interferon beta vs glatiramer acetate), CONFIRM (dimethyl fumarate (DMF) vs glatiramer acetate), OPERA (ocrelizumab vs interferon beta), REGARD (interferon beta vs glatiramer acetate), RIFUND-MS (rituximab vs DMF), TENERE (teriflunomide vs interferon beta) and TRANSFORMS (fingolimod vs interferon beta). Treatment effects estimated in emulated trials were concordant with RCT findings in seven of eight trials for relapse rate, and in all six trials assessing disability progression. Radiological outcomes were more challenging to replicate; concordance was achieved in three of five trials for new T2-lesions, and one of four trials for new gadolinium-enhanced T1-lesions.Conclusion: The combined use of a TTE methodology and high-quality registry data is a valid tool to evaluate treatment effectiveness in MS
Entre mobile et immobile. La route au cœur des tensions écologiques
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The role of Al addition on the hydrogen sorption properties of TiVZrNbHf high entropy alloy
No full textDiamond Light Source , B18 under the Energy Materials Block Allocation Group (BAG)International audienceRefractory BCC high entropy alloy TiVZrNbHf is a promising material for solid-state hydrogen storage with high hydrogen sorption capacity but unfavourable thermodynamics of hydride phase, i.e. too stable hydride that need high temperature to reversibly recover the absorbed hydrogen. As an attempt to destabilize the hydride phase, this study reports on the effect of Al addition (limited concentrations: 5 and 10 at.%) into this alloy on the physicochemical and hydrogen sorption properties. Despite traces of a V-Al secondary phase, the BCC (TiVZrNbHf)1-xAlx alloys are random solid solutions which form high-capacity FCC hydride phases under hydrogen atmosphere at room temperature, as proven by synchrotron and neutron diffraction. Although Al decreases the hydrogen sorption capacity, the presence of p element destabilizes the FCC hydride phase. A comparison with previous literature data helps understanding the role of Al which strongly depends on the chemical composition of the initial alloys. XANES studies allowed access to details of the electronic structure of the unoccupied levels complemented by density functional theory calculations. Moreover, the addition of Al favours the formation of larger open volume defects during hydride formation than the initial Al-free alloy which might explain the faster absorption kinetics in Al-containing alloys
An asymptotic shape theorem for additive random linear growth models
No full textInternational audienceIn this paper, we define a class of additive random growth models whose growth is at least and at most linear and prove an asymptotic shape theorem for these models. This proof generalizes already known proofs for the classical contact process or some of its variants and allows us to obtain conjectured asymptotic shape theorems for Richardson's model with stirring and the contact process with stirring
Territoria Naturalia. Aménager sans altérer, entre partage et réserve
No full textInternational audiencehttps://www.calameo.com/read/004309853d5506947d879Face aux crises environnementales — dérèglement climatique, effondrement de la biodiversité, artificialisation croissante — l’aménagement du territoire est contraint de se réinventer. Longtemps fondées sur une approche technique et fragmentée de l’écologie, les politiques d’urbanisme sont aujourd’hui mises à l’épreuve par de nouvelles exigences réglementaires, par les mobilisations citoyennes et par les transformations visibles de nos environnements.Territoria Naturalia propose une autre manière de penser l’action territoriale en explorant les modèles du land sparing et du land sharing, issus de l’écologie de la conservation. Intensifier les usages afin de libérer des espaces de nature préservée, ou au contraire intégrer le vivant dans des pratiques plus extensives : entre ces deux approches, une palette d’arbitrages éclaire les choix qui façonnent villes et campagnes à l’heure du Zéro Artificialisation Nette.À travers une lecture renouvelée des tensions entre anthropisation et préservation, et en s’appuyant sur des expérimentations concrètes, cet ouvrage transdisciplinaire invite à repenser les outils, les pratiques et les finalités mêmes de l’aménagement afin d’accompagner les transitions territoriales
