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The power of expressed humility: Early stage investors' reaction to humble entrepreneurs
No full textInternational audienceAbstract Research Summary We examine how entrepreneur‐expressed humility affects early stage investors' willingness to fund new ventures. In pitching contexts where investors rely on relational cues and implicit prototypes of entrepreneurs, we theorize three distinct pathways through which expressed humility shapes funding decisions. First, building on research regarding interpersonal signals in early stage valuation, we propose that humility fosters perceptions of interpersonal affect and trust and team‐building qualities, increasing investors' willingness to fund. Second, drawing on implicit leadership theories, we argue that humility may trigger negative perceptions regarding the entrepreneur's ability to make rapid and risky decisions. Across a videometric analysis of 140 real‐world pitches and a randomized experiment with French early stage investors, we show that expressed humility elicits both pathways, but investors prioritize positive attributions. Managerial Summary Although humility is often regarded as a positive leadership trait, it contradicts implicit prototypes of successful entrepreneurs, who are typically seen as dominant and assertive. We examine how early stage investors perceive and respond to displays of humility during pitches. We propose that entrepreneur‐expressed humility produces ambiguous effects: It enhances perceptions of interpersonal affect and trust and team‐building qualities, but raises doubts about the entrepreneur's ability to make rapid and risky decisions. Using a videometric analysis of 140 pitches from the French version of Shark Tank and a randomized experiment with venture capital investors, we find evidence for these competing pathways. Overall, investors prioritize the positive attributions of interpersonal skills, suggesting that entrepreneurs benefit from expressing humility when pitching
Clinically‐Relevant Static Magnetic Field Induces Release of Encapsulated Molecules from Magnetoliposomes
No full textInternational audienceMagnetoliposomes (MLs) are known for their great potential in drug release under an alternating current (AC) magnetic field (MF). However, AC magnetic fields require specific setups that remain poorly implemented worldwide, contrary to direct currents (DC) that are present in widely used magnetic resonance imaging (MRI) devices. In this work, we evidence the feasibility of a drug release triggered by a 1.5 T constant MF, currently used in clinics. The structuration of magnetite nanoparticles (NPs) stabilized by surface adsorption of citric acid (Fe 3 O 4 :CA NPs), and an optional chitosan shell (Fe 3 O 4 :CA:CS NPs) to enhance cytocompatibility, was followed under a 1.5 T constant by small‐angle X‐ray scattering (SAXS), and dynamic light scattering (DLS). MLs encapsulating both Fe 3 O 4 :CA NPs and fluorescent carboxyfluorescein (CF), were also submitted to 1.5 T, and the CF fractional release was monitored. The effect of Fe 3 O 4 :CA:CS NPs addition externally to MLs in the suspension was investigated. Results evidenced that both Fe 3 O 4 :CA and Fe 3 O 4 :CA:CS NPs formed necklace‐like aggregates under DC MF. Fluorescence experiments demonstrated a significant CF release from MLs, which was enhanced by the addition of external NPs, while empty liposomes exhibited negligible releases. Finally, a biological evaluation of MLs and NPs revealed an excellent cytocompatibility
Guglielmo di Conches, Il dialogo di Filosofia, Introduzione, Traduzione e Commento
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Géométrie plane des q-rationnels et les opérations de Springborn
No full textInternational audienceWe study the geometry of q-rational numbers, introduced by Morier-Genoud and Ovsienko, for positive real q. In particular, we construct and analyse the deformed Farey triangulation and the deformed modular surface. We interpret every q-rational geometrically as a circle, similar to the famous Ford circles. Further, we define and study new operations on q-rationals, the Springborn operations, which can be seen as a quadratic version of the Farey addition. Geometrically, the Springborn operations correspond to taking the homothety centers of a pair of two circles. Contents 1. Introduction 1 2. From q-integers to q-rationals to q-reals 5 3. Hyperbolic geometry and deformed Farey tesselation 9 4. Deformed Farey determinants and operations 18 5. Classical Springborn operations 24 6. Springborn operations for q-rationals 32 7.</div
Estimation basée sur la forêt aléatoire de la mesure d'analyse de sensibilité globale orientée quantile
No full textThis thesis is devoted to the estimation and application of Quantile-Oriented Sensitivity Analysis (QOSA) measures, including the first-order QOSA indices, the total QOSA indices, and the Quantile-Oriented Shapley Effects (QOSE) indices, which provide a natural and interpretable extension when input variables are dependent. Compared with variance-based measures, QOSA indices are both more robust and more informative, as they capture distributional features beyond variance. Our first contribution is the development of a new quantile-oriented random forest, which achieves performance comparable to other state-of-the-art random forest approaches for quantile regression. Building on this tool, we integrate the projected algorithm to estimate conditional quantiles given a subset of inputs. This enables the estimation of QOSA indices through a straightforward plug-in procedure. We establish consistency results for the conditional quantile estimators and three type QOSA indices. The final part of the thesis focuses on the application of QOSE in meteorology. We demonstrate that QOSE indices can effectively identify and rank the most influential input variables, thereby offering practical guidance for model simplification and for allocating computational resources more efficiently.Cette thèse est consacrée à l'estimation et à l'application des mesures d'analyse de sensibilité orientée quantile (QOSA), incluant les indices QOSA de premier ordre, les indices QOSA totaux et les indices d'effets Shapley orientés quantile (QOSE). Ces mesures offrent une extension naturelle et interprétable lorsque les variables d'entrée sont dépendantes. Comparés aux mesures basées sur la variance, les indices QOSA sont à la fois plus robustes et plus informatifs, car ils capturent les caractéristiques distributionnelles au-delà de la variance. Notre première contribution est le développement d'une nouvelle forêt aléatoire orientée quantile, dont les performances sont comparables à celles des autres approches de pointe en matière de régression quantile. En nous appuyant sur cet outil, nous intégrons l'algorithme projeté pour estimer les quantiles conditionnels à partir d'un sous-ensemble d'entrées. Ceci permet l'estimation des indices QOSA grâce à une procédure simple de plug-in. Nous établissons des résultats de consistance pour les estimateurs de quantiles conditionnels et trois indices QOSA de type. La dernière partie de la thèse porte sur l'application de la QOSE en météorologie. Nous démontrons que les indices QOSE peuvent identifier et classer efficacement les variables d’entrée les plus influentes, offrant ainsi des conseils pratiques pour la simplification des modèles et pour l’allocation plus efficace des ressources de calcul
Catheter ablation in congenital heart diseases: a French nationwide study
No full textInternational audienceBackground and aims: Current evidence on catheter ablation for patients with congenital heart disease (CHD) is derived from small, retrospective studies. This study aims to provide insights from a nationwide contemporary registry.Methods: This prospective study included all CHD patients referred for catheter ablation from 2020 to July 2024 across 28 French centres. The primary outcome was the rate of per-procedural acute success. Secondary outcomes included complications as well as freedom from arrhythmia recurrence.Results: A total of 1135 consecutive catheter ablation procedures were performed in 998 patients (mean age 46.1 ± 16 years, 55.5% male). The main primary clinical arrhythmias targeted were atrial flutter/tachycardia in 677 (59.6%), atrial fibrillation in 195 (17.2%), ventricular arrhythmia in 188 (16.6%), and atrioventricular reentrant tachycardia in 38 (3.3%), with significant variations in patterns observed based on the underlying substrate. Clinical arrhythmia was successfully ablated in 1071 patients (94.4%). The mean number of arrhythmias targeted per procedure was 1.5 ± 0.7, with overall acute success rates exceeding 90% for all arrhythmias except for ventricular arrhythmias (86.7%). Acute complication occurred in 43 procedures (3.8%), including 1 (0.1%) death. The overall 1- and 2-year recurrence-free rates were 77.3% (95% confidence interval 74.2%-80.4%) and 68.4% (95% confidence interval 64.7%-72.3%), respectively. Significant variations in recurrence rates were noted based on the type of arrhythmia and the underlying CHD.Conclusions: Catheter ablation in patients with CHD demonstrates highly favourable acute outcomes and a low complication rate. Recurrence rates during follow-up vary depending on the targeted arrhythmia and the underlying CHD. These findings should be considered in the benefit-risk assessment.Pre-registered Clinical Trial Number NCT0420279