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Modelling soil erosion focusing on event-size occurrences under global change in a vineyard catchment
No full textInternational audienceSoil erosion is a balance between forces acting to detach and transport sediment and those resisting, such as soil cohesion or protection of vegetation cover. The amount of eroded particles is proportional to the acting forces, but the feedback, as is widely acknowledged, has a non-linear behaviour. Moreover, most of the erosion is concentrated in the strongest events, as evidenced by many authors.Here, in a long-term simulation, we investigate the occurrence of the size of the erosion events in a vineyard catchment area. We analysed around 700 rainfall events over 20 years from two climate series (historical 1985-2005, and and future 2040-2060), and four contrasted land use and management scenarios.The results confirmed that the erosion is driven by a limited number of strong events with an increment in future series due to an increase in frequency of the more severe rainfall events. We observed that: 1) Size of erosion events VS return time exhibit different logarithmic trends in each LU scenario; 2) Long-term erosion series show that the few major erosion phases are due to a limited number of events, the most severe; 3) The concentration of erosion events towards the highest values is more pronounced in intensified landscape indicating more reactive erosion than in protected landscapes.This suggests that controlling the state of intensification of a landscape (i.e. intensified or preserved) can mitigate soil erosion even if climate change tends to increase erosion rates
Potential of polysaccharides for food packaging applications. Part 1/2 : An experimental review of the functional properties of polysaccharide coatings
No full textInternational audienceEnvironmental issues related to the use of plastic packaging have sparked a growing interest in the development of more sustainable solutions. Biopolymers, used alone or in combination with other materials, have been considered a potential alternative to conventional fossil-based plastics. Hence, this study aimed at unraveling the potentiality offered by polysaccharides for food packaging applications. To that purpose, an extended characterization of the barrier (to oxygen and water vapor), mechanical and optical properties (transparency and UV-blocking ability) of nine different polysaccharide films (hydroxypropyl methylcellulose, methylcellulose, hydroxypropyl cellulose, low-methoxyl pectin, cationic starch, sodium alginate, kappa-carrageenan, chitosan, and pullulan) was performed to provide a broad overview of their main physicochemical properties under standardized conditions. In addition, the properties of the film-forming solutions, such as viscosity and surface tension, were also evaluated. All polysaccharides obviously presented low water vapor barrier performance due to their hydrophilic nature (water vapor permeance from 10−6 to 10−8 mol.m-2.s-1.Pa-1). Among all the polysaccharides studied, chitosan, low-methoxyl pectic, kappa-carrageenan, pullulan, cationic starch and sodium alginate, displayed medium to very high oxygen barrier performance in semi-dry (50% RH) and humid (80% RH) conditions (oxygen permeance from 10−13 to 10−15 mol.m-2.s-1.Pa-1), contrarily to cellulose derivatives which showed the poorest performance (oxygen permeance >10−12 mol.m-2.s-1.Pa-1). This opens on interesting perspectives for the use of polysaccharides as coating materials for high oxygen barrier packaging
The cell transformation assay to assess potential carcinogenic properties of nanoparticles.
No full textInternational audienceNanoparticles (NPs) are present in many daily life products with particular physical-chemical properties (size, density, porosity, geometry …) giving very interesting technological properties. Their use is continuously growing and NPs represent a new challenge in terms of risk assessment, consumers being multi-exposed. Toxic effects have already been identified such as oxidative stress, genotoxicity, inflammatory effects, and immune reactions, some of which are leading to carcinogenesis. Cancer is a complex phenomenon implying multiple modes of action and key events, and prevention strategies in cancer include a proper assessment of the properties of NPs. Therefore, introduction of new agents like NPs into the market creates fresh regulatory challenges for an adequate safety evaluation and requires new tools. The Cell Transformation Assay (CTA) is an in vitro test able of highlighting key events of characteristic phases in the cancer process, initiation and promotion. This review presents the development of this test and its use with NPs. The article underlines also the critical issues to address for assessing NPs carcinogenic properties and approaches for improving its relevance
Éleveurs et vaches dans l’épaisseur et l’accélération du temps. Quand le progrès génétique n’attend pas
No full textClaire nous a quitté le 27 avril 2022 et n’a donc pas eu le temps de mettre la dernière main à notre article. Elle nous accompagne cependant toujours…International audienceThe long history of domestic animal breeding has been marked by the ever closer association between technology and economic development. Knowledge of DNA and genomic selection have become the benchmark for genetic progress in dairy cows. Based on an extensive qualitative survey conducted on the Montbéliarde breed in the Jura region, we address this innovation as well as the concept of ‘time’ which, in the absence of ontological status, enabled us to approach the complexity of breeding today. The changes underway illustrate the modern forces of acceleration based on time measurement and life expressed as equations. Acceleration can be explained by the creation of increasingly extensive interdependencies between actors and activities, the pressure of markets and constant innovations. However, on farms, we observe that the times of animals and of humans remain intertwined. Times as lived and narrated by farmers offer other perspectives on the world; they show the indeterminacy of events in the face of a future to be predicted and the multiplicity of lines of life, work, nature and human beings that make up livestock farming. Moreover, in the narratives, hesitations about innovations and job meaning seem to be the last defence against progress and the passage of time. Can these times coexist or does the ever earlier selection of animals, which compresses time, risk taking away the pleasure of the breeder’s work?La longue histoire de la sélection des animaux domestiques est marquée par l’association toujours plus étroite entre les technologies et le développement économique. Aujourd’hui, la connaissance récente de l’ADN devient une référence incontournable pour la sélection des troupeaux, en particulier des vaches laitières. À partir d’une large enquête qualitative menée sur la race Montbéliarde dans l’arc jurassien, nous interrogeons cette innovation ainsi que le concept de temps qui sans statut ontologique, nous permet de dilater la complexité de l’élevage aujourd’hui. D’un côté, ces changements illustrent fidèlement les nombreux travaux qui démontent les ressorts modernes de l’accélération, mais de l’autre, les pratiques et les mots qui les accompagnent pointent aussi le fait que la durée peut rester à la base des compétences des éleveurs et du sens qu’ils accordent à leur métier
Chapter 19 - Safety concerns on biological contaminations in fermented foods: Special focus on fungi and mycotoxins
No full textInternational audienceThere are rising concerns regarding the consumption of fermented foods regarding their safety to microbial contaminations from fermenting consortium and food processing materials. On the other hand, there has been a dramatic increase in demand for safe foods and the major concerns are not just associated with the methods of food production, but also with all stages across the supply chain. Mycotoxins, produced by some groups of fungi, are known to impact on significant economic loss. Their presence in foods at levels above regulatory limits brings about adverse effects on sustainable food supply, posing health risks to humans and animals, as well as limitations on international trade. Mycotoxins such as aflatoxins, ochratoxin A, fumonisins, deoxynivalenol and citrinin are the majorly identified in the etiology of food safety concerns causing numerous food-borne diseases. This chapter discusses fungi-mycotoxin contaminations in different fermented food products, highlights the major components influencing the microbial safety of fermented foods (including lack of proper processing and handling, and poor storage conditions which could trigger the production of these naturally occurring toxic compounds) as well as their impacts on economic and human health. From the various studies reviewed, mycotoxins were mainly detected in soy-based (tempeh, doenjang, soy sauce, meju, miso and shoyu) and rice-based (Red yeast rice and sake) fermented food products. Hence, there is a need for the integration of mycotoxin mitigation actions to safeguard the quality of raw materials used in food fermentation and to ensure the consumption of safe and healthy foods
Quels effets des opérations de travail du sol sur la fragmentation des racines du chardon des champs (Cirsium arvense) ?
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Evaluation d’impact du Programme Opérationnel FEDER-FSE 2014-2020 Nord Pas de Calais et du Programme Opérationnel FEDER-FSE 2014-2020 Picardie. Axe 4 –Volet quantitatif
No full textThis report presents the ex-post evaluation of the impacts of the 2014-2020 FEDER-FSE Operational Programs of the former Nord-Pas-de-Calais and Picardie regions. The approach used is that of evaluating specific effects using a double difference method with matching on the propensity score. By mobilizing a panel of statistical data sources located at the municipal level to construct a set of control variables, the impacts of the 205 projects financed within the framework of axis 4 of these OPs are examined from the point of view of attractiveness economic and residential. The analysis highlights a short-term effect of FEDER/FSE OPs, positive on residential attractiveness and face-to-face employment in Picardy, positive on face-to-face employment in Nord-Pas-De-Calais, but does not reveal significant effect on residential attractiveness in Nord-Pas-De-Calais.Ce rapport présente l'évaluation ex-post des impacts des Programmes Opérationnels FEDER-FSE 2014-2020 des ex-régions Nord-Pas-de- Calais et de Picardie. La démarche mobilisée elle celle de l'évaluation des effets propres recourant à une méthode de doubles différences avec appariement sur le score de propension. En mobilisant un panel de sources de données statistiques localisées à l'échelle communale pour construire un jeu de variables de contrôle, les impacts des 205 projets financés dans le cadre de l'axe 4 de ces PO sont examinés point de vue de l'attractivité économique et résidentielle. L'analyse met en évidence un effet de court terme des PO FEDER/FSE, positif sur l’attractivité résidentielle et l’emploi présentiel en Picardie, positif sur l’emploi présentiel en Nord-Pas-De-Calais, mais ne révèle pas d’effet significatif sur l’attractivité résidentielle en Nord-Pas-De-Calais
The bacterial species profiles of the lingual and salivary microbiota differ with basic tastes sensitivity in human
No full textInternational audienceTaste perception is crucial and impairments, which can be linked to pathologies, can lead to eating disorders. It is triggered by taste compounds stimulating receptors located on the tongue. However, the tongue is covered by a film containing saliva and microorganisms suspected to modulate the taste receptor environment. The present study aimed to elucidate the links between taste sensitivity (sweetness, sourness, bitterness, saltiness, umami) and the salivary as well as the tongue microbiota using shotgun metagenomics. 109 bacterial species were correlated with at least one taste. Interestingly, when a species was correlated with at least two tastes, the correlations were unidirectional, indicating a putative global implication. Some Streptococcus , SR1 and Rickenellaceae species correlated with five tastes. When comparing both ecosystems, saliva appears to be a better taste predictor than tongue. This work shows the implication of the oral microbiota in taste and exhibits specificities depending on the ecosystem considered
Nitrogen Footprint Assessment of Korean Native Beef Cattle Farms: Uncertainty Analysis and Mitigation Scenarios
No full textInternational audienceNitrogen (N) lost during beef cattle production accompanies various environmental impacts and has become an increasing concern among agricultural stakeholders. The objective of this study was to quantify the N footprint (NF) of Hanwoo beef cattle production in Korea at the farm gate through a life cycle assessment methodology. Field surveys were conducted on 106 farms across nine provinces to evaluate the NF of Hanwoo beef farms. N losses were calculated using emission factors using the refined Intergovernmental Panel on Climate Change (IPCC) guideline and expressed as NF [g N lost/kg of live body weight (LBW)]. Uncertainty and sensitivity analyses were deployed to evaluate the precision of the results and to quantify the variability of the input data. The NF was averaged 132.8 (±61.9) g N/kg LBW. Volatilization was the greatest contributing factor, followed by leaching and denitrification, each representing 68.4, 21.4, and 10.1 percent of the NF, respectively. The uncertainty of the output data was found to be 46.6 percent and was highly associated with emission factors uncertainties. We simulated four feasible mitigation scenarios that are cost effective and do not penalize productivity, and evaluated their capacity for reducing NF of meat: dietary modifications to decrease animal N excretion rates by adjusting the CP and rumen undegradable protein content for steers and fattening cows (A), microorganism additives to reduce volatilization from housing and manure storages through processing excess ammonium to synthesize microbial protein (B), using manure as land fertilizer instead of synthetic fertilizers to decrease denitrification from rice cultivation, and leaching and volatilization from all field types(C), and distributing straw-derived biochar (10 to 20 ton/ha) to the field after fertilizer application to reduce losses from crop production (D).Combining these scenarios demonstrated the potential to reduce NF by 12.3 percent. Overall, our study provides a national metric that can be used to communicate the N uses impact of Korean beef production. The analyses indicate that more precise results could be achieved with future endeavors toward developing country-specific emission factors. Integrating all four scenarios was shown to be the most effective approach to reducing the NF of beef production