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Impact of flash release treatment of lees on mannoprotein content during white wine ageing
No full textInternational audienceThis study investigates the impact of adding treated wine lees processed by flash release (FD), with or without enzymatic treatment, on the polysaccharide composition, molecular weight distribution, and sensory properties of Chardonnay wines aged on lees for six months. Standard oenological parameters (pH, total and volatile acidity, SO 2 content, and alcohol) remained largely unaffected by lees addition, except for a slight pH and acidity increase in wines with 5 % untreated lees. Polysaccharide and oligosaccharide analyses revealed a significant increase in mannoproteins (MPs) content, especially in wines supplemented with FD-treated lees and FD-treated lees with enzymes, reaching concentrations up to 600 mg/L. FD treatment enhanced the extraction of high-molecular-weight polysaccharides, whereas enzymatic treatment by β-glucanase promoted their depolymerisation into mid-sized molecular fractions. High-performance size exclusion chromatography with a multi-angle laser light scattering (HPSEC-MALLS) analysis identified five major molar mass populations, with distribution patterns varying according to lees treatment. Sensory evaluation showed that wines aged with untreated lees exhibited more pronounced yeast and reductive aromas, whereas those aged with FD + enzyme-treated lees were perceived as more fruity, more acidic, and with greater aromatic persistence. Overall, the data demonstrate that flash release and enzymatic pre-treatment of lees significantly modify the colloidal composition of wine, with implications for both wine stability and sensory profile.</div
Evaluation of pectin and fiber in Cambodian mango peel and pulp from young to ripe maturity stages - a tool for industry
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/616285/) * Autres projets (id;sigle;titre): ;SWM Programme;(EU) Sustainable Wildlife Management Programme//International audienceIn tropical countries, the mango sector generates high volumes of byproducts (peel, seeds, rejects, etc.) that need to be valorized. This research carried out on Cambodian Keo Romeat mango waste, was undertaken to support the mango industry. The aim was to better understand how ripening stage and processing method impact the final quality of the products, e.g., animal feed, especially as regards to soluble pectin and fiber content. Mangoes were selected from four ripening stages from young (i.e., green) to over-ripe mango, and processed using blanching and drying, drying or freeze-drying. The characterization of macronutrient (pectin, fiber, ash, lipid, carbohydrate and moisture) content was achieved in pulp and peel for each ripening stage and process treatment. Results showed that both processing and ripening had a significant impact on fiber and soluble pectin content even if ripening always had a greater effect. Maximizing both pectin and fiber contents in the mango pulp or peel was not possible, since the anti-correlation between their concentrations during ripening presented an R² of >0.7. Indeed, when fiber content decreased, the pectin content increased in mango peel and pulp. A simple 4-dimensional data representation was helpful for industrial growers and processors, enabling them to make suitable and appropriate choices between ripening and the processing needs according to the desired product quality without requiring specialized knowledge in food science
Balancing stability and flexibility in climate crises governance: Lessons from Brazil's water sector
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/616266/) * Autres projets (id;sigle;titre): 16–2014 ODISSEIA;;(BRA) INCT ODISSEIA//International audienceClimate-induced crises such as droughts and floods increasingly strain public institutions, particularly where authority is fragmented and decisions must be made under urgency and uncertainty. This article examines Brazil's river-basin monitoring rooms as procedural instruments of water crisis governance. Adopting a pragmatist lens that links practical authority and policy instrumentation, we analyze two cases—São Francisco and Paraíba do Sul—using a qualitative, multi-source research design. We show that monitoring rooms enable flexible, real-time coordination by combining technical forecasting with structured, bounded deliberation. Their authority is built in practice through recurrent mechanisms: problem-solving under uncertainty, translation of hydrological and energy data into accessible terms, and sustained relational work that supports trust and compliance. Monitoring rooms complement basin committees by bridging urgent crisis response with longer-term governance, and they have become institutionalized through repeated crisis use. The discussion situates these findings within collaborative governance and policy instrumentation debates, and highlights how similar procedural arenas in other domains (e.g., wildfire or pandemic response) can make governance more workable under stress
Temperate phage evolve to integrate host stress and quorum signals in lysis-lysogeny decisions
No full textInternational audienceTemperate phage can transmit both horizontally (lytic cycle) and vertically (lysogenic cycle). Many temperate phage have the ability to modify their lysis/lysogeny decisions based on various environmental cues. For instance, many prophage are known to reactivate when SOS stress responses of their host are triggered. Temperate phage infecting Bacilli can also use peptide signals (“arbitrium”) to control their lysis/lysogeny decisions. However, information from the arbitrium and SOS systems can be potentially conflicting, and it is unclear how phage integrate information carried by these two different signals when making lysis–lysogeny decisions. Here, we use evolutionary epidemiology theory to explore how phage could evolve to use both systems to modulate lysis/lysogeny decisions in a fluctuating environment. Our model predicts that it can be adaptive for phage to respond to both host SOS systems and arbitrium signaling, as they provide complementary information on the quality of the infected host and the availability of alternative hosts. Using the phage phi3T and its host Bacillus subtilis , we show that during lytic infection and as prophage, lysis–lysogeny decisions rely on the integration of information on host condition and arbitrium signal concentrations. For example, free-phage are more likely to lysogenise a stressed host, and prophage are less likely to abandon a stressed host, when high arbitrium concentrations suggest susceptible hosts are unavailable. These experimental results are consistent with our theoretical predictions and demonstrate that phage can evolve plastic life-history strategies to adjust their infection dynamics to account for both the within-host environment (host quality) and the external environment that exists outside of their host (availability of susceptible hosts in the population). More generally, our work yields a new theoretical framework to study the evolution of viral plasticity under the influence of multiple environmental cues
L'étude des chaînes relationnelles : un domaine de l'analyse de réseau sociaux à développer
No full textInternational audienceThe study of relational chains is one of the approaches used in social network analysis. It consists of documenting the activation of relationships between people in processes of accessing resources or other people. This approach makes it possible to study the phenomena of embeddedness (the dependence of various social activities on networks of relationships between individuals) and, more generally, the overall structure of networks in various socio-historical contexts.L'étude des chaînes relationnelles est l'une des approches utilisées en analyse des réseaux sociaux. Elle consiste à documenter l'activation de relations entre personnes dans des processus d'accès à des ressources ou à d'autres personnes. Cette approche permet d'étudier les phénomènes d'encastrement (la dépendance d'activités sociales diverses relativement aux réseaux de relations entre les personnes) et plus généralement la structure générale des réseaux dans des contextes sociohistoriques variés
Sweet taste induced by miraculin from Sisrè pulp (Synsepalum dulcificum Schumach. & Thonn.) from Benin as affected by heat treatment
No full textInternational audienceThis work focused on the effect of heating treatments on the sweetening property of miraculin contained in Sisrè, the fruit of Synsepalum dulcificum, from Benin. The aim was to define suitable conditions for stabilizing the fruit pulp, at a lower cost while preserving its functional properties. The fruits, collected in the locality of Sèhouè in the Republic of Benin, were frozen whole, pulped and then stored at -20 • C before processing and analyzing. Heat treatments ranging from 40 to 70 • C were applied to the fresh pulp for 5 min. Sensory tests were performed on the heated pulp samples to test the functionality of miraculin and determine the remanence time of the induced sweet taste after treatment at different temperatures. Reverse-phase and steric-exclusion chromatography, in association with electrophoresis were performed to analyze the miraculin content of the pulps, and the generated data were compared with the sensory results. Sensory analysis showed that the sweetening effect of the native pulp before heat treatment lasted at least >1 h 30 min. A significant loss of functionality after exposure of the pulp to temperature values above 50 • C was observed. The results of analyses also showed that from 50 • C, the miraculin concentration decreased significantly. At temperature values above 50 • C, miraculin completely lost its functionality even if the pulp still contained miraculin, probably in its monomeric form that are not active. The intensity and remanence of the sweetening effect of miraculin depended on its concentration. These results demonstrated that the pulp of Sisrè cannot be stabilized by thermal pasteurization and that drying at low temperatures between 40 and 50 • C could be a good technological option for preserving its functionality
Emotions et dispositifs participatifs en recherche-action sur la transition écologique : risques de normalisation des émotions et de tarissement de la critique sociale ?
No full textInternational audienceCet article examine un dispositif participatif de recherche-action sous l’angle des émotions impliquées dans la transition écologique de la Camargue (Bouches-du-Rhône, France). Il questionne les éventuelles limites que ce type de dispositif impose à la prise en compte des émotions dans les débats et la réflexion collective. Différents processus micro-interactionnels et organisationnels sont pointés comme conduisant à un filtrage émotionnel avec pour conséquences de favoriser une conception technique et téléologique de la transition écologique, de limiter la critique sociale et d’inciter une normalisation des émotions citoyennes et de leurs modalités d’expression
Identifiability and Observability Analysis for Epidemiological Models: Insights on the SIRS Model
No full textInternational audienceThe problems of observability and identifiability have been of great interest as previous steps to estimating parameters and initial conditions of dynamical systems to which some known data (observations) are associated. While most works focus on linear and polynomial/rational systems of ODEs, general nonlinear systems, including non-analytic systems have received far less attention and, to the best of our knowledge, no unified constructive methodology has been proposed to assess and guarantee parameter and state recoverability in this setting. Some symbolic tools provide automated analyses for rational or nonlinear, analytical systems, offering qualitative identifiability and observability verdicts that are sometimes incomplete. In this work, we introduce a family of efficient and fully constructive procedures that can enable explicit recovery of the unknown parameters and/or initial conditions, whenever possible, for a large class, not necessarily rational or analytic, nonlinear ODE systems. Each procedure is tailored to different observational scenarios and based on the resolution of linear systems. As a case study, we apply these procedures to several epidemic models, with a detailed focus on the SIRS model, demonstrating its joint observability-identifiability when only a portion of the infected individuals is measured, a scenario that has not been studied before. In contrast, for the same observations, the SIR model is observable and identifiable, but not jointly observable-identifiable. This distinction allows us to introduce a novel approach to discriminating between different epidemiological models (SIR vs. SIRS) from short-time data. For these two models, we illustrate the theoretical results through some numerical experiments, validating the approach and highlighting its practical applicability to real-world scenarios
Overview of LifeCLEF 2025: Challenges on Species Presence Prediction and Identification, and Individual Animal Identification
No full textInternational audienceBiodiversity monitoring using AI-powered tools has become vital for tracking species distributions and assessing ecosystem health on a large scale. Automated image- and sound-based species recognition, in particular, continues to accelerate conservation efforts by enabling rapid, low-cost surveys of vulnerable populations. However, the ever-growing variety of algorithms and data sources underscores the need for standardized benchmarks to assess real-world performance. Since 2011, the LifeCLEF lab has filled this role by organizing annual evaluations that promote collaboration among AI experts, citizen science, and ecologists. In this overview, we report on the LifeCLEF 2025 edition, which featured five distinct, data-driven tasks: (i) AnimalCLEF, focusing on open-set individual animal re-identification; (ii) BirdCLEF+, about species recognition in complex acoustic soundscape recordings; (iii) FungiCLEF, addressing few-shot classification of rare fungi species; (iv) GeoLifeCLEF, combining environmental and high-resolution remote sensing with occurrence records to predict plant species presence; and (v) PlantCLEF, aiming to identify multiple co-occurring plant species in vegetation-plot imagery. This paper provides an overview of the motivation, methodology, and main outcomes of the five challenges
Share the ride: The determinants of long-distance carpooling pricing strategies in France
No full textInternational audienceThis paper investigates the pricing strategies used in long-distance carpooling in France. We investigate how several factors affect carpooling prices using a comprehensive dataset of BlaBlaCar trips combined with sociodemographic and intermodal competition data. The analysis identifies two distinct pricing patterns within the platform: one characterized by standardized and consistent pricing, and another marked by more flexible, market-responsive price setting. By focusing on price per minute, we examine how trip characteristics, competitive conditions, and demand heterogeneity affect these pricing behaviors. The results show that variables such as the number of stopovers, trip length, airport or cross-border connections, and the presence of alternative transport modes influence pricing, but with contrasting effects across the two patterns. The standardized approach tends to reflect cost-sharing principles and reinforces network effects, while the more flexible approach adapts dynamically to local competition and demand