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Individual and combined impacts of water immersion, steaming at 100 °C and hot air drying on the cashew nut shelling process
No full textInternational audienceAbstract Shelling cashew nuts is a highly labour-intensive process that often results in broken kernels, reducing efficiency and economic value. Improving shelling techniques is crucial for increasing whole kernel yield, reducing waste, and enhancing sustainability in the cashew industry. In this study, the aim was to investigate the impact of pre-treatments (water immersion, steaming and artificial drying) applied alone or in combination to weaken the nut and facilitate shelling. An experimental approach incorporating microtomography was used to identify the importance of each step and the factors controlling the process. The results show that water content is the main factor influencing whole kernel yield, shelling rate and shell toughness. Hydration during soaking makes the shell more flexible and reduces kernel cracking, while steaming intensifies this effect. Rapid drying keeps the kernel hydrated and makes the shell brittle, improving the production rate. The study suggests that steaming alone might sufficiently saturate the shell, eliminating the need for soaking. In addition, artificial drying reduces the duration of the process. The results obtained provided a better understanding of the process control variables with a view to its improvement. Further studies on process modelling could provide insights into optimising the yield of whole kernels
Assessing sustainable and healthy diets in large multi-country surveys: Validity and applicability of a brief food group propensity questionnaire based on the EAT-Lancet planetary diet
No full textInternational audienceIntroduction: Nutritional strategies ensuring healthy diets within planetary boundaries are essential. In 2019, the EAT-Lancet Commission proposed the planetary health diet, prompting the creation of several indices to measure intake. However, these methods may be impractical for large-scale surveys due to complexity, respondent burden, and resource demands. Thus, concise and valid tools measuring intake frequency can enhance response rates, reduce costs, and simplify administration. This study aimed to develop a simplified and practical tool for representing EAT-Lancet diet adherence in large-scale multi-country surveys.Methods: First, an intake frequency index for EAT-Lancet diet food groups (ELFI) was developed using data from the INCA3 survey (n=1,645) and applying a quantile based-scoring system. ELFI was validated by correlating it with a valid EAT-Lancet index (ELI), nutritional health measures (nutrient adequacy and diet quality), and environmental impact (Agribalyse). Second, ELFI applicability for large surveys was tested in the FEAST survey of 27,417 adults from 27 European countries. Analyses included reliability, structural validity (exploratory and confirmatory factor analyses), concurrent validity (multivariate regression), and structural equation modeling (SEM).Results: Expected associations with demographic variables confirmed ELFI concurrent validity (age, gender, income, education; p<0.05). ELFI correlated with ELI (0.43, p<0.001), and food groups correlation ranged 0.10–0.48 (p<0.001). ELFI food groups correlated with quantities consumed (-0.15–0.49, p<0.001). SEM showed that higher scores in ELFI subscores were associated with better Nutritional Health (β=0.73 and 0.37, p<0.001) and lower Environmental Impact (β=-0.22 and -0.38, p<0.001). Regarding applicability in the FEAST survey, ELFI mean score was 20.43 (3.48), with red meats scoring lowest (1.08 (0.91)) and oils highest (1.79 (0.92)). ELFI showed strong reliability (ω=0.82) and factor analysis revealed a two-factor solution (40% variance; KMO=0.86): one for whole grains, vegetables, fruits, legumes, nuts, fish, and oils; and another for red meats, poultry, eggs, fats, tubers, sugars, and dairy. All models in confirmatory factor analysis demonstrated adequate fit, with the bifactor model supporting the use of ELFI. Conclusion: The ELFI approach represents a valuable and easy-to-implement tool for evaluating adherence to sustainable and healthy diets in large-scale studies
Identifiability and Observability Analysis for Epidemiological Models: Insights on the SIRS Model
No full textThe 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 have received far less attention and, to the best of our knowledge, no general constructive methodology has been proposed to assess and guarantee parameter and state recoverability in this context. We consider a class of systems of parameterized nonlinear ODEs and some observations, and study if a system of this class is observable, identifiable or jointly observable-identifiable; our goal is to identify its parameters and/or reconstruct the initial condition from the data. To achieve this, we introduce a family of efficient and fully constructive procedures that allow recoverability of the unknowns with low computational cost and address the aforementioned gap. 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 joined 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
Ecosystem-Scale Biodiversity in Fisheries Life Cycle Impact Assessment
No full textInternational audienceThe impact of fisheries was recently operationalised in Life Cycle Assessment, accounting for effects on individual exploited species at both regional and global scales. Now, this emergent pathway is expanded to the ecosystem scale by incorporating additional indirect impacts associated with fishing through the integration of ecosystem dynamics. The methodology combines a novel coupling of dynamic ecosystem modelling and Species Sensitivity Distribution curves to quantify fisheries effects on marine biodiversity, using an adaptation of the USEtox Effect Factor modelling that assesses community-scale ecotoxicity impacts. Innovative elements include the incorporation of indirect effects through a fished community via predator-prey interactions, and a bidirectional threshold interval that captures both potential population depletion and expansion dynamics resulting from exploitation. A proof of concept is presented in the Adriatic Sea, deriving novel midpoint Characterisation Factors for 26 exploited Functional Groups, with impacts reported in Potentially Affected Fraction (PAF) units. Impact values are spread over six orders of magnitude (1.58×10 -7 PAF small/medium rays -2.16×10 -1 PAF small pelagic fish), validating the operability of the approach. Methodological choices and assumptions introduced by the novel approach are discussed. The original combination of modelling tools employed in this characterisation approach contributes to the progressive enhancement of the fisheries impact pathway and how biodiversity loss is considered in Life Cycle Impact Assessment. SYNOPSISThe impacts of increasingly unsustainable exploitation of global wild-capture fisheries on marine biodiversity necessitates the development of an approach capable of quantifying ecosystem-scale fisheries impacts in Life Cycle Assessment.</div
When is Agrivoltaism Environmentally Beneficial? A Consequential LCA and Scenario Discovery Approach
No full textInternational audienceAt the crossroads of climate change and land-competition, agrivoltaic systems (AVS) propose a land-sharing synergy between photovoltaic (PV) electricity and crop production or animal husbandry. By partially covering crops with PV panels, AVS can enhance food production by maintaining favorable micro-climatic conditions and can constitute a promising adaptation to climate change. However, the AVS electric and crop production performances vary extensively across crop types, climates, panel orientations etc. While the few existing Life Cycle Assessment (LCA) studies evaluating AVS' environmental performance, cover a minor part of this diversity of configurations, a planned deployment policy for AVS requires extensive knowledge on the configurations that may or may not environmentally outperform conventional alternatives, i.e., conventional PV electric and crop productions. To identify these configurations, we built a parameterized consequential LCA model that simulates an AVS either driven by electricity demand or by crop demand. We then applied a scenario discovery algorithm over stochastic AVS configurations to identify groups of AVS configurations that perform better or worse than their conventional counterparts. By parameterizing the technological and agronomical contexts, the interactions between PV and crop productions and the electricity and land markets, we provide insights regarding how AVS should be designed, promoted or discouraged
Compared analysis of re-built long-term historical annual pressures of Botrytis Bunch Rot, Noble Rot and Downy Mildew in Bordeaux vineyards
No full textInternational audienceThe grapevine life history covers many decades, and the perennial crop is exposed year after year to several biotic hazards, including major harmful diseases, such as Botrytis bunch rot “BBR” (Botrytis cinerea) and downy mildew “DM” (Plasmopara viticola). B. cinerea is also known as the causal agent of the Noble rot “NR” process in maturing berries, resulting in highly prized, full-bodied sweet wines. Our aim was to reconstruct the grapevine past exposure to the two diseases and the NR process in the Bordeaux vine-growing region. The corresponding time series were analyzed based on specifically-designed annual prevalence/severity indicators.We used NR data from the Sauternes area, near Bordeaux, thanks to collaboration with Château d’Yquem. As for BBR and DM, we used advisory bulletins, provided to growers for almost one century by the French Agriculture Ministry. This information, from field disease monitorings by experts, was exploited by developing the following textual analysis (Fermaud et al, 2024, IOBC-WPRS Bulletin 171). First, for every disease and year, we extracted the keywords related to pathogen occurrence/prevalence within a given area, and its associated overall damage/severity. Second, by transforming these data into semi-quantitative scores and combining them, we designed an overall annual semi-quantitative score for every disease. The analyses of resulting databases from 1940 onwards, compared, for B. cinerea, the differences in vineyard expression and development according to the process considered, BBR vs NR. Furthermore, we compared the inter-annual dynamics patterns of the two major diseases BBR vs DM, by also investigating a possible interaction at this large temporal scale.In the current context of global warming and rapid changes in regulatory conditions, investigating and comparing such historical annual epidemic pressures may contribute to anticipate the necessary evolution(s) of grapevine protection and production systems, including also for such key pathogens, potential development of specific insurance policies
Saccharomyces cerevisiae Concentrates Subtoxic Copper onto Cell Wall from Solid Media
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The white lupin CCR1 receptor-like kinase controls systemic Autoregulation of Cluster Root and Nodule Development
No full textInternational audienceRoot development is tightly regulated in plants to optimize nutrient acquisition and interactions with soil microorganisms. In legumes, the Autoregulation of Nodulation (AoN) pathway systemically controls the proliferation of root nodules, which are energy-intensive organs. Mutations affecting the AoN pathway result in a hypernodulation phenotype accompanied by altered root development. However, it remains unclear whether this modification of root development is also systemic and coordinated with nodulation. In this study, we report the identification of the constitutive cluster root 1 (ccr1) mutant in white lupin ( Lupinus albus ), which exhibits constitutive production of an excessive number of cluster roots. We demonstrate that CCR1 is an ortholog of HAR1/SUNN/NARK leucin-rich repeat-receptor like kinases (LRR-RLKs), which are key regulators of the AoN pathway. Furthermore, we show that CCR1 negatively regulates both nodule and cluster root development. Interspecific grafting experiments between white and narrow-leaved lupin ( Lupinus angustifolius ), a species incapable of producing cluster roots, show that ccr1 shoots can induce the formation of cluster-like roots in narrow-leaved lupin rootstocks. This highlights the conservation of a CCR1-dependent signaling cascade. Transcriptome analyses reveal that CCR1 targets the conserved NIN/LBD16-NFYA regulatory module, which connects nodule and lateral root development through a shared inhibitory systemic pathway. We propose that this pathway represents a broader developmental control mechanism of root organogenesis, termed Autoregulation of Cluster Root and Nodule Development (AoDev)
Un outil d’aide à la décision pour élaborer une stratégie collective de sécurisation de l’AEP
No full textInternational audienceGrowing pressure on water resources is posing new challenges for stakeholders in the drinking water supply (DWS) sector, calling on them to think collectively on a larger scale than that on which they currently operate. To support these evolutions, the present article proposes an original decision-support approach, combining a participatory approach and modeling. The approach is based on the co-construction and participatory use of a hydro-economic model simulating the operation of the drinking water supply system, taking into account interdependencies between drinking water supply management entities (through shared resources and interconnection infrastructure). This approach makes it possible to explore different prospective scenarios, to collectively plan for future drinking water supply security on a relevant scale. The approach was implemented in Sud-Finistère (Brittany, France), engaging the different stakeholders involved with drinking water management in the region. It has built a shared vision of the challenges facing drinking water management in the region, and quantified the future water deficits for different prospective scenarios co-constructed with stakeholders. Various types of results and indicators, notably maps, are available for analysis to identify any limiting factors and bottlenecks. Building on these diagnoses, the approach has made it possible to assess the effectiveness of multiple adaptation measures and combinations of measures co-constructed by stakeholders. The simulations provide objective information on the expected effects of the measures, facilitating dialogue between stakeholders who may have differing preconceptions as to their effectiveness, thereby fuelling collective planning on the actions to be implemented to secure future drinking water security. The proposed approach was positively evaluated by the participants. It is replicable in other regions where needed.Les tensions croissantes sur les ressources en eau posent de nouveaux défis aux acteurs de l’alimentation en eau potable (AEP), les invitant à réfléchir collectivement à une échelle plus large que celle à laquelle ils fonctionnent actuellement. Pour accompagner ces évolutions, cet article propose une démarche d’aide à la décision originale, combinant approche participative et modélisation. La démarche s’appuie sur la co-construction et l’utilisation participative d’un modèle hydro-économique simulant le fonctionnement du système d’approvisionnement en eau potable, prenant en compte les interdépendances entre les collectivités (ressources partagées, interconnexions). L’approche permet d’explorer différents scénarios prospectifs pour réfléchir de façon collective à la sécurisation de l’AEP à une échelle pertinente. La démarche a été mise en œuvre dans le Sud Finistère, mobilisant les différents acteurs de la gestion de l’eau potable du territoire. Elle a permis de construire une vision partagée des enjeux de gestion de l’AEP sur le territoire, d’anticiper et de quantifier les déficits ressources-besoins des collectivités pour différents scénarios d’évolutions futures co-construits avec les parties prenantes. Différents types de résultats et d’indicateurs, notamment des cartographies, sont analysables en sortie de simulation pour identifier les éventuels facteurs limitants et points de blocage. Face à ces diagnostics, la démarche a permis d’évaluer l’efficacité de multiples mesures et combinaisons de mesures d’adaptation proposées par les acteurs. Les simulations fournissent une base d’information objective sur les effets attendus des mesures, facilitant le dialogue entre des parties prenantes pouvant avoir des a priori divergents quant à leur efficacité, et alimentant ainsi la réflexion sur les actions à entreprendre pour orienter favorablement l’avenir. La démarche proposée a été évaluée positivement par les participants. Elle est reproductible sur d’autres territoires