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Continuing opportunity recognition in young ventures—the role of founder and joiner experience
No full textInternational audienceWe analyze the continuing role of prior technical experience of top-management team (TMT) members for opportunity recognition beyond the initial market entry choice in young ventures. We are drawing on and extending the theory of opportunity recognition by studying continuing opportunity recognition and by distinguishing the roles of founders and joining TMT members. Specifically, we investigate the recognition of digital opportunities by young ventures initially focused on a non-digital offering for a sample of 6672 firms. First, our study shows that founders’ prior technical experience influences opportunity recognition beyond the time of founding. Second, whereas founders contribute to opportunity recognition with both general and specialized prior knowledge, joining TMT members have a narrower role because for them just specialized prior knowledge is relevant. We contribute to the entrepreneurship literature by providing a more nuanced understanding of the role of prior knowledge for opportunity recognition
A new definition of human health is needed to better implement One Health
No full textInternational audienceSince the COVID-19 pandemic, One Health approaches1 have revived attention to the interdependence of human, animal, and ecosystem health. However, human health is still predominantly viewed through the prism of disease affecting humans and related care activities, as illustrated by health expenditure and health regulation. This approach is now overly restrictive since interdependencies and holistic approaches are crucial for the prevention and preservation of human health, particularly in relation to interlinked climate, biodiversity, pollution, and health crises. We claim that redefining WHO's definition of human health will facilitate actual implementation of One Health approaches in the medical field, improve pandemic prevention, and reflect the many ways in which health determinants have evolved. Although the funding and very existence of WHO are under attack, with dramatic consequences on worldwide global health, WHO should seize the opportunity to change the definition of human health and thereby reinvent itself, showing its ability to evolve with the international context, base its recommendations and policies on updated science, and promote multilateralism and its values
Strategic Reneging and Market Power in Sequential Markets
No full textInternational audienceThis article investigates the incentives for firms with market power to manipulate markets by strategically reneging on forward commitments. We first study the behavior of a dominant firm in a two‐period model with demand uncertainty. We then use the model's predictions and a machine learning approach to investigate multiple occurrences of reneging on long‐term commitments in Alberta's electricity market in 2010–2011. We find that a supplier significantly increased its revenues by strategically reneging on its capacity availability obligations, causing Alberta's annual electricity procurement costs to increase by as much as $600 million (+17%)
A meta-analysis of supervised and unsupervised machine learning algorithms and their application to active portfolio management
No full textInternational audienceThis article applies latest machine learning algorithms, such as clustering or classification, to build and actively manage portfolios invested in U.S. stocks. We conduct a meta-analysis to compare the efficiency of these algorithms as stock screeners and their behavior during different market phases (before, during, and after the Covid-19 crisis), and to identify the best investing strategy. A two-step methodology is proposed for selecting stocks and monthly rebalancing the obtained portfolios. The first step relies on a two-stage filter accounting for stock fundamentals in a given year (annual data), and the statistical features of their returns over the last three years (daily data). This first step highlights the most determining stock fundamental ratios, which are extracted from financial statements and balance sheet data. Such insightful ratios drive the stock selection process while the statistical features supplement a monthly filter that drives portfolio rebalancing. The second step focuses on five portfolio optimization schemes and compares the performance of the resulting efficient stock portfolios.The above methodology applies four clustering and four classification algorithms to select stocks based on unsupervised and supervised learning approaches. Findings reveal two outperforming optimal portfolios resulting from the best pairs of stock selection algorithms and portfolio optimization metrics. The first-best investment strategy mixes the HAC algorithm with the maximum diversification ratio optimization scheme, and the second-best strategy pairs the random forest algorithm with the maximum diversification optimization scheme. Thus, we empirically demonstrate the usefulness of machine learning techniques for efficiently building active portfolios that beat the market
Antimony mining and metallurgy in the Brioude-Massiac district (Massif Central, France): historical features and perspectives
No full textInternational audienceThe Brioude-Massiac district played a key role in antimony mining in France. While in Roman times, complex polymetallic veins (Pb-Ag-Sb) were exploited, most likely for Pb and Ag only, Sb veins gained interest in the 17 th century. Numerous mines were opened, playing a significant role in the French production. Nowadays, mining and smelting activities are long gone but remnants are still clearly visible. On one hand, numerous galleries, shafts and mining wastes are witnesses of historic mining activity; on the other hand, scarcer smelting remains can be observed, as ruins of plants or as accumulation of artisanal smelting artefacts. Based on a literature review, field examination and classical petrography, the present study documents the Brioude-Massiac district in order to discuss its value as a geoheritage site and to broaden it towards an international audience, since most of the relevant works about this district are in French. As a A type-locality for a major Sb ore (berthierite FeSb 2 S 4 ), it is also known since at least the 18 th century for magnificent stibnite (Sb 2 S 3 ) crystallisations. Smelting activities (liquation and oxidizing roasting) have left traces such as ruins of former plants and various slags (locally used as aggregates) which yield interesting samples. Hence, it can be seen that the patrimonial value of this district allows a holistic approach of all aspects of Sb, from geology, mining and smelting. Based on a literature review, field examination and classical petrography, the present study documents the Brioude-Massiac district in order to discuss its value as a geoheritage site and to broaden it towards an international audience, since most of the relevant works about this district are in French.</div
The Future of Inductive Voltage Transformers in Power Quality Measurement
No full textInternational audienc
De maîtresse à domestique. La circonstance aggravante de « vol dans une auberge » au prisme du genre (1799-1815)
No full textInternational audienceThis article examines the concept of theft and, more specifically, one of its aggravating circumstances, theft from an inn. While the law of 16 December 1799 provided for an aggravation of the punishment if the theft was committed by the 'master or mistress of the inn', the penal code of 1810 took up this circumstance, masculinising it by removing the term 'mistress'. A study of the text and the debates reveals the performativity of the language of the law and its role in the gender order: the doctrine points to a ruling that chooses the qualification of 'domestic theft' and makes the wife of an innkeeper a 'servant' rather than a 'mistress' - although there was nothing to prevent this. Under the umbrella of the supposedly universal masculine, women are made invisible and denied the status to which they are not explicitly entitled.Au XIX e siècle comme de nos jours, certaines dispositions pénales sont ab initio marquées par le genre : soit elles prévoient un traitement différencié pour les hommes et les femmes, soit elles ne concernent que les uns ou que les autres. Par exemple, jusqu'en 1975, le mari peut bénéficier d'une excuse légale s'il tue sa conjointe adultère, alors que la réciproque n'est pas permise 1 . De même, le crime de castration est genré puisqu'il ne concerne que des victimes masculines, la castration étant associée à l'organe génital masculin 2 . Un dernier exemple dispose qu'en 1810, les femmes ne peuvent être condamnées aux travaux forcés qu'à l'intérieur des maisons de force, à la différence des hommes 3
Trifolium subterraneum as a potential nurse plant for restoring soil and Mediterranean grasslands after quarry exploitation in Lebanon
No full textInternational audienceDestruction of Mediterranean herbaceous communities resulting from quarry exploitation exacerbates the need for their ecological restoration. By facilitating the growth and development of other plant species, nurse plants can be used to speed up regeneration processes. Nevertheless, differences in soil properties and co-existing species may change plant interactions from facilitation to competition. This study evaluated interactions of a potential nurse species, Trifolium subterraneum L., in a 2-years ex situ mesocosm experiment. During the first year, soils collected from a former quarry and a nearby dry-grassland were planted in pots with T. subterraneum alone or with four individuals of four target species (Aegilops triuncialis L., Echinops viscosus L., Eryngium creticum Lam., Hyoscyamus aureus L.) characteristics of Mediterranean grasslands. In the second year, the same experiment was repeated following the incorporation of dried T. subterraneum biomass into the soil. Soil analyses were done before initiating the experiment from both reference and degraded soil, after the first and the second growing season. Index of Relative Interaction Intensity (RII) was calculated for several plant traits enabling the measuring of the plants' competitive ability. Our results show that, before starting the experiment, soils collected from both the reference and degraded sites were significantly different (e.g. CEC, pH, P 2 O 5 , MgO, N, C, Clay). These differences were still notable throughout the first growing season. Nevertheless, after the second growing season and whendried. T. subterraneum biomass was incorporated into the soil, a significant increase in soil fertility (e.g. N, C, C:N, P 2 O 5 ) was measured. For plants, during the first growing season, RII figures amidst competition dominating interactions. Facilitation was apparent only between the biomass of T. subterraneum pure seed mix in both degraded and reference soil. During the second growing season, T. subterraneum also performed better alone, especially on degraded soils. Nevertheless, because of its facilitative effects on biomass and surface cover when cultivated as a pure stand, T. subterraneum can be recommended as a nurse species for re-establishing soil fertility of degraded quarries as a first step of ecological restoration
Programmes de Restauration Fonctionnelle du Rachis : étude rétrospective et comparative de l’efficacité des différentes orientations thérapeutiques
No full textInternational audienceBackground: Functional Spine Restoration (RFR®) programs have evolved to incorporate a group-based approach and educational sessions aimed at promoting behavior change. The objective of this study is to compare the effectiveness of a physical fitness-focused program (RFR1) with an enhanced version that integrates cognitive-behavioral and empowerment strategies (RFR2). Methods: This retrospective study includes 88 participants in the RFR2 group and 144 in the RFR1 group. Data were collected on flexibility, muscular endurance, physical function, and quality of life (Dallas). Measurements were taken at the beginning and end of the program, as well as at 3 and 6 months (the 6-month follow-up was conducted only for RFR1). RFR2 is structured around a group-based care model with five staggered cohorts, whereas RFR1 follows an individualized approach focused on physical reconditioning. Results: Both programs led to improvements in physical and mental health, but RFR2 demonstrated superior effectiveness in the medium term. The inclusion time was reduced from 150 to 90 days, aligning with HAS recommendations. Conclusion: The multidimensional approach of RFR2 optimizes patient care by enhancing autonomy and quality of life. However, some limitations associated with the retrospective nature of the data warrant further analysis. Unlike RFR1, which shows a declining trend over time, RFR2 highlights the benefits of a holistic, collective, and autonomy-oriented approach. It extends beyond mere physical reconditioning, empowering patients to actively manage their low back pain.Contexte : Les programmes de Restauration Fonctionnelle du Rachis (RFR®) ont évolué en intégrant une approche de groupe et des séances éducatives visant le changement de comportement. L’objectif est de comparer l’efficacité d’un programme axé sur le reconditionnement physique (RFR1) à une version enrichie avec des approches cognitivo-comportementales et d’autonomisation (RFR2). Méthodes : Cette étude est rétrospective et intègre 88 sujets pour RFR2 et 144 pour RFR1. Les données collectées concernent la flexibilité, l’endurance musculaire, la fonction physique et la qualité de vie (Dallas). Les mesures ont été réalisées en début et fin de programme, puis à 3 et 6 mois (6 mois uniquement pour RFR1). RFR2 est basé sur une prise en soin collective avec 5 groupes en quinconce, contrairement à RFR1, individualisé et centré sur le reconditionnement physique. Résultats : Les deux programmes améliorent la santé physique et mentale, mais le RFR2 montre une meilleure efficacité à moyen terme. Le délai d’inclusion a diminué de 150 à 90 jours, en accord avec les recommandations de la HAS. Conclusion : L’approche multidimensionnelle de RFR2 optimise la prise en soin, renforçant l’autonomie des patients et leur qualité de vie. Toutefois, certaines limites des données rétrospectives appellent à approfondir l’analyse. Contrairement à RFR1, qui montre une dynamique baissière, RFR2 confirme l’intérêt d’une prise en soin globale, collective et autonome, dépassant le simple reconditionnement physique pour responsabiliser pleinement le patient dans la gestion de sa lombalgie
Minimum information for studies of extracellular vesicles (MISEV) as toolbox for rigorous, reproducible and homogeneous studies on extracellular vesicles
No full textInternational audienceStudies based on extracellular vesicles (EVs) have been multiplying exponentially for almost two decades, since they were first identified as vectors of cell-cell communication. However, several of these studies display a lack of rigor in EVs characterization and isolation, without discriminating between the different EV populations, thus generating conflicting and unreproducible results. There is therefore a strong need for standardization and guidelines to conduct studies that are rigorous, transparent, reproducible and comply with certain nomenclatures concerning the type of EVs used. The International Society for Extracellular Vesicles (ISEV) published the Minimum Information for Studies of Extracellular Vesicles (MISEV) in 2014, updating it in 2018 and 2023 to reflect different study contexts and technical advancements. The primary objective of this review is to inform future authors about EVs, including their history, nomenclature, and technical recommendations for the for isolation and functionality analysis for conducing EV-based studies according to current standards. Additionally, it aims to inform reviewers about the key parameters required for characterizing EV preparations.</div