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Bayesian Adaptive Sampling: A Smart Approach for Affordable Germination Phenotyping
No full textInternational audienceDigital phenotyping is rapidly advancing, generating increasing amounts of data, particularly in the case of temporal monitoring. We propose an adaptive sampling method that optimizes sampling, thereby reducing costs associated with data production, processing, and storage. The proposed method is based on Bayesian inference, which utilizes previous measurements, historical data, and an expected model. Five Bayesian methods are assessed in this study: Important sampling (IS), Markov chain Monte-Carlo (MCMC), Gaussian process (GP), Extended Kalman filtering (EKF) and Sampling Importance Resampling particle filtering (SIR-PF). We test these five Bayesian sampling methods for the monitoring of germination rate in terms of compression, distortion and computation cost. The best trade-off is found by the MCMC method, which offers a compression rate of 0.2 with very little distortion. GP offers the most unbiased parameter estimation and the capability to adapt to various germination speeds. It also has reasonable computational times
Enhancing Hydrological Modeling with Bias-Corrected Satellite Weather Data in Data-Scarce Catchments: A Comparative Analysis of SWAT and GR4J Models
No full textInternational audienceHydrological models are widely used to assess climate change effect on water resources at the catchment scale. However, data scarcity is one of the main challenges faced by hydrological modelers especially in developing countries. Remotely sensed and large-scale climatic datasets offer a viable alternative for hydrological modeling. Hence, this study evaluates CFSR-NCEP reanalysis data for discharge simulation using SWAT semi-distributed and GR4J conceptual lumped hydrological models. First, the CFSR-NCEP monthly reanalysis precipitation and temperature were compared to the observed data. Then, the performance of SWAT and GR4J models to simulate monthly discharge using both daily CFSR-NCEP reanalysis data with and without bias correction was compared across different climate conditions. Results indicated that the GR4J model performed well, with an average NSE of 0.89 across calibration and validation periods, indicating its ability to handle low-quality input data. A poor performance of the SWAT model was observed using CFSR-NCEP data without bias correction (NSE < 0.60). Primarily due to biases in meteorological data, and to low quality of spatial data. Bias correction improved both models' performance, with NSEs exceeding 0.78 for SWAT model and 0.91 for GR4J model. Moreover, the stability of models' performances under the three calibration periods shows that SWAT and GR4J models are respectively influenced and not much influenced by the climate of the calibration period. Consequently, GR4J remains valid for climate projection. Our research shows that despite their widespread use, complex physics-based hydrological models such as SWAT are often less performing in data-limited catchments. However, conceptual models prove more performing, providing valuable information for researchers and decision-makers to devise robust quantitative water resource management strategies under these challenging conditions
DETERMINATION OF CALCIUM BIOACCESSIBILITY IN FOOD SOURCE OF DIETARY CALCIUM
No full textInternational audienceCalcium is an essential nutrient required for biological functions. The recommended daily intake according to the WHO is 1000 mg of calcium per day for adults. However, calcium deficiency is widespread worldwide. Half of the world's population does not have adequate access to dietary calcium, particularly in diets with low dairy consumption. In addition, we are moving towards a healthier and more sustainable diet where it is recommended to increase the consumption of plant-based foods and reduce animal products (including dairy).This work aimed to study the bioaccessibility of calcium of 12 food sources of dietary calcium (plant food sources and dairy products), using an in vitro static gastrointestinal digestion model (INFOGEST). Calcium bioaccessibility was determined by the soluble fraction relative to total calcium present in the matrix. Soluble calcium content was measured at different time point of the gastric and intestinal digestion using inductively coupled optical emission spectrometry.During in vitro digestion, it was observed that the pH influenced the solubility of calcium for all the food matrices tested. Calcium is almost completely solubilized during the gastric phase at pH 3. During the intestinal phase, calcium solubility decreases considerably due to the increase of pH to 7. The presence of fat apparently affects calcium solubility in our model, probably though the formation of insoluble complexes in the intestinal phase. Indeed, matrices with higher fat content have a lower calcium solubility in the intestinal phase. A yogurt made from partially skimmed milk (1 g fat /100 g of food) has 0,52 g/L of soluble calcium whereas semi skimmed milk (1,6 g fat /100 g of food) has only 0,31 g/L. In addition, the best bioaccessibility at the end of the intestinal phase was observed for partially skimmed milk yogurt (34% ±0) followed by broccoli (27%± 1) and cheese (19%± 2). Calcium enriched plant-based drinks seem closer to semi-skimmed milk (21%±3 vs 26%± 2, respectively). On the other hand, fresh cheese, chickpea, whole almond, soy dessert and plant-based cheese-like product have very low calcium bioaccessibility (≤6%). If the ingested portion is considered to calculate calcium bioaccessibilities, dairy products (cheese, milk and yoghurt) are the best source of bioaccessible calcium. Indeed, ingesting a portion of yogurt (125 ml) represents 64.8mg of bioaccessible calcium compared to a portion of broccoli (80 g) which represents only 13.5mg of calcium.Thus, calcium is more bioaccessible in dairy products than in plant food sources
Identification of plant resistance inducers and evaluation of genotype receptivity for carrot protection against Alternaria leaf blight
No full textInternational audienceThe use of biopesticides represents an alternative strategy to synthetic chemical products for crop protection. To promote their adoption and effective use by growers, it is crucial to understand their modes of action and the optimal conditions for their application in crops, including their compatibility with specific varieties. Through a series of greenhouse experiments, this study describes the development and validation of a robust molecular diagnostic tool for enabling the evaluation of defence gene activation. The results identified plant resistance inducers (PRIs) among biopesticide products capable of protecting carrots against Alternaria leaf blight. By applying a PRI to a range of carrot varieties exhibiting varying levels of resistance to Alternaria dauci , preliminary findings on plant receptivity suggest that the efficacy of PRIs in conferring protection is highly dependent on the treated variety. Two distinct genotype-dependent effects were observed: sensitivity to the PRI and an enhancement of resistance. This study offers new insights into optimising biopesticide use in carrot cultivation
Life cycle assessment of a minimal process using membrane filtration replacing pasteurization for infant formula production at a semi-industrial scale
No full textInternational audienceInfant formula is essential for providing the necessary nutrients for infants aged 0-3 years. But infant formula production also faces a critical challenge: ensuring both nutritional quality and environmental sustainability. Traditional heat treatment processes, while ensuring microbiological safety, have been shown to cause protein denaturation, thereby reducing the nutritional quality of the product [1]. As an alternative, Yu et al. [1] proposed membrane microfiltration to replace the pasteurization process, which aims to preserve the nutritional value of infant formula.We conducted a detailed Life Cycle Assessment (LCA) comparing the environmental impacts of infant formula production on a semi-industrial scale between the traditional pasteurization route and the proposed alternative microfiltration route, using the EF 3.0 method. Our findings indicate that the alternative route does not significantly reduce the environmental impacts of infant formula production compared to the traditional method. Specifically, in the “climate change” impact category, the classic route emits 10.45 kg of CO2 equivalent, whereas the alternative route results in 11.14 kg of CO2 equivalent. The higher emissions associated with the alternative route primarily stem from the increased demand for skimmed milk, which is linked to the production of a bacterial-rich by-product during microfiltration.This study represents the first comprehensive analysis of the environmental impacts of infant formula at a semi-industrial scale. It offers valuable insights into eco-design strategies for mitigating these impacts, such as incorporating liquid ingredients instead of powdered ones in formulations, which can reduce energy consumption during vacuum evaporation and drying processes. Additionally, increasing the dry extract in pre-evaporation formulations can help limit water evaporation needs
QuaDS: A qualitative/quantitative descriptive statistics Python module
No full textInternational audienceIn this research, we introduce a new Python bioinformatics tool. QuaDS (Quantitative/Qualitative Description Statistics) is a pipeline tailored to describe a factor (a qualitative variable of interest) in heterogeneous datasets consisting of qualitative and quantitative variables. This pipeline separately analyze s the variables related to the factor using appropriate statistical tests. The QuaDS pipeline offers an interactive visualization that describes the factor. Several parameters can be defined by the user to ensure the most personalized results based on their data
OneWater FAIR Data Platform : towards a national FAIR water data platform and community
No full textInternational audienceThe French program OneWater - Eau Bien Commun (2022-2032) aims to better manage water as a common good. It generates a wide range of data (scientific, social, models) that are not yet in line with FAIR principles.To remedy this, a national FAIR platform is currently being developed. It aims to create an ecosystem of interoperable data, beyond a simple catalog, based on international standards and national and global collaborations.Three axes are being developed:1 -A survey to identify needs and build the platform with users.2- An adaptation of FAIR principles to the water sector, with grids tested on existing data.3 - A technical architecture in line with recent standards (OGC, W3C, etc.) incorporating FAIR best practices.The project reinforces access, sharing and reuse of water-related data
Pathogenicity of Ascochyta nigripycnidia, Didymella pinodella and Boeremia exigua isolated from Trifolium alexandrinum in Algeria and assessment of their host range on some Fabaceae
No full textInternational audienceBerseem clover (Trifolium alexandrinum L.) is an important forage crop for livestock farming in Algeria. This crop is susceptible to many fungal diseases that can affect yield and forage quality. Surveys carried out in several regions of Algeria, enabled us to collect a large number of diseased samples from berseem crops showing symptoms of leaf spot and stem/root necrotic diseases, commonly known as Ascochyta Blight (anthracnosis). Among the fungal species isolated and identified, three species Ascochyta nigripycnidia, Didymella pinodella, and Boeremia exigua were considered in this study. To assess the pathogenicity and the host range of these three species, eight isolates (3 A. nigripycnidia, 3 D. pinodella, and 2 B. exigua) were selected and inoculated on the above and below-ground parts of berseem, alfalfa, vetch, pea, chickpea, and faba bean. Disease incidence and severity disease were assessed on leaves, epicotyls and roots of the inoculated plants. All these fungal species had caused serious symptoms on the organs of the Fabaceae studied, with varying levels of attacks according to the species and the isolates tested. A. nigripycnidia caused severe attacks on berseem and chickpea, but showed little severity on alfalfa, vetch, and pea. This is the first evidence that A. nigripycnidia is not specific to vetch, but can attack other Fabaceae. D. pinodella showed no specialization, and attacked indifferently all inoculated organs of the tested species. In the end B. exigua was the least aggressive pathogen on the legumes tested, and was more pathogenic on berseem leaves and roots
Evaluation de la durabilité de fermes laitières AB avec ou sans transformation à la ferme: Analyse de groupe - Projet VEG&LAIT - Module de Master 1
No full textPreface: Hydrological Sciences in the Anthropocene – a structured community effort
No full textInternational audienceThe International Association of Hydrological Sciences (IAHS) celebrated its centennial in 2022 during the 11th Scientific Assembly held over 29 May–3 June in Montpellier(France); and is celebrating in 2024 a century of publications. This volume materializes the proceedings of the 2022 Assembly and marks the anniversary of the long-term publi cation dynamics, with articles tackling very actual problems and questions, from across many countries of the World. The International Association of Hydrological Sciences/Association Internationale des Sciences Hydrologiques (IAHS) was created in 1922 in Rome (Italy) in the form of the International Section of Scientific Hydrology/Section Internationale d’Hydrologie Scientifique of the International Union of Geodesy and Geophysics/Union Internationale de Géodésique et Géophysique (IUGG), itself member of the International Research Council/Conseil International de Recherches both created in 1919 in Brussels (Belgium) (Nature, 1928; Schroeder-Gudehus, 2014, Ismail zadeh and Joselyn, 2019) (Names in French language are kept here as it was the language used for the proceedings at the time). The IAHS developed over a century as described by osbjerg and Rodda (2019), alongside the parent IUGG (Joselyn and Ismail-Zadeh, 2019; Joselyn et al., 2019) and sister learned societies (including the emergence in 2007 of the international Association of Cryospheric Sciences (IACS); Allison et al., 2019) and with strong partnerships in the United Nations system, in particular with UNESCO IHP and WMO (see e.g. Young et al., 2015a, b; Dixon et al., 2022). The records of the first plenary meeting of the Section in 1924 shaped the first volume of the Section’s bulletin (Sec-tion Internationale d’Hydrologie Scientifique, 1924), which then became the Red Book series in 1951 with volume 32 (where the red colour was first used to highlight the cover