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SEPURE : de nouvelles solutions d'empoissonnement pour les étangs en France
No full textNational audienc
Overcoming divergence: managing expectations from organisers and members in community supported agriculture in Switzerland
No full textThis paper is based on the master thesis written by the first author with the title: “Community Supported Agriculture in Switzerland: A Photo-elicited Story of Idealists and Pragmatist Shifting Paradigms in Agriculture”.International audienceCommunity supported agriculture (CSA) is a producer-consumer union that aims to shift the predominant paradigm in agriculture towards a model based on social justice, fairness, and participation. However, the long-term existence of CSA initiatives, and their ability to build the social capital envisioned by the initiators, can be challenged by a struggle to generate a sufficient income for a fair salary to be paid to the producer. This study aimed to explore the main challenges faced by eight CSAs in Switzerland, along with the pathways they used to address them. The expectations and perceptions of organisers were collected through indepth photo elicitation interviews, which were analysed using grounded theory. The perspective of members was evaluated using a quantitative survey with 254 responses. The results showed that organisers are often filled with enthusiastic ideas but experience a sense of deflation when they realise that the members follow a more pragmatic approach. The information flow from members to the organisers leading them to new insights for adjustments, is a key component in overcoming divergence between the expectations of members and organisers. Involving members in administration and fieldwork lowers the workload of the organisers and fosters informal social interactions and mutual understanding, which leads to an increase in social capital. Focusing on local embeddedness and co-creation between members and organisers, thus allowing a dynamic evolution of the CSA, was found to be more beneficial for the long-term existence of the CSA than rigidly trying to implement the initial vision of the organisers
Interaction of Escherichia coli heat-labile enterotoxin B-pentamer with exopolysaccharides from Leuconostoc mesenteroides P35: Insights from surface plasmon resonance and molecular docking studies
No full textInternational audienceIn this study, the interaction of exopolysaccharides from Leuconostoc mesenteroides P35 (EPS-LM) with Escherichia coli heat-labile enterotoxin B-pentamer (LTB) was investigated at different concentrations and temperatures by using surface plasmon resonance (SPR) and molecular docking approaches. FT-IR spectral analysis together with HPTLC analysis revealing that glucose is the only constitutive monosaccharide of EPS-LM suggests that its structure is composed of dextran with α-D (1 → 6) glycosidic linkages. SPR analysis revealed the high affinity of EPS-LM for immobilized LTB toxin (KA=(2.05 ± 0.04) × 106 mol.L−1 at 37°C). The binding process was spontaneous (ΔG<0), endothermic (ΔH>0), and entropy-driven (ΔS>0) with an increase of KA with temperature. This suggests that EPS-LM - LTB interaction is dominated by hydrophobic forces. The binding affinity of EPS-LM to LTB had negligible dependence on enthalpy (ΔH = 0.084 kJ mol−1). Further, molecular docking results suggested the presence of some binding sites of EPS-LM on the LTB through hydrophobic forces (Lys, Asp, Arg, Glu) and also hydrogen bonding (Glu) in the hydrophobic core of LTB. Besides autodock studies, Schiffer-Edmundson helical wheel diagrams of LTB in α-helix domain suggested that LTB hydrophobic core is a highly effective region, which was able to form favorable non-polar interactions of the protein's binding surface (with amino acids residues such as Tyr, Leu, Ile) with EPS-LM. This study provided thus further insights into the interactions between EPS-LM and LTB, suggesting that EPS produced by some LAB, such as EPS produced by Ln. mesenteroides P35 strain are good candidates to inhibit E. coli toxin activity
Advancements in Biodegradable Active Films for Food Packaging: Effects of Nano/Microcapsule Incorporation
No full textInternational audienceFood packaging plays a fundamental role in the modern food industry as a main process to preserve the quality of food products from manufacture to consumption. New food packaging technologies are being developed that are formulated with natural compounds by substituting synthetic/chemical antimicrobial and antioxidant agents to fulfill consumers’ expectations for healthy food. The strategy of incorporating natural antimicrobial compounds into food packaging structures is a recent and promising technology to reach this goal. Concepts such as “biodegradable packaging”, “active packaging”, and “bioactive packaging” currently guide the research and development of food packaging. However, the use of natural compounds faces some challenges, including weak stability and sensitivity to processing and storage conditions. The nano/microencapsulation of these bioactive compounds enhances their stability and controls their release. In addition, biodegradable packaging materials are gaining great attention in the face of ever-growing environmental concerns about plastic pollution. They are a sustainable, environmentally friendly, and cost-effective alternative to conventional plastic packaging materials. Ultimately, a combined formulation of nano/microencapsulated antimicrobial and antioxidant natural molecules, incorporated into a biodegradable food packaging system, offers many benefits by preventing food spoilage, extending the shelf life of food, reducing plastic and food waste, and preserving the freshness and quality of food. The main objective of this review is to illustrate the latest advances in the principal biodegradable materials used in the development of active antimicrobial and antioxidant packaging systems, as well as the most common nano/microencapsulated active natural agents incorporated into these food-packaging materials
Major transcriptomic, epigenetic and metabolic changes underly the pluripotency continuum in rabbit preimplantation embryos
No full textDespite the growing interest in the rabbit model for developmental and stem cell biology, the characterization of embryos at the molecular level is still poorly documented. We conducted a transcriptome analysis of rabbit pre-implantation embryos from E2.7 (morula stage) to E6.6 (early primitive streak stage) using bulk and single-cell RNA-sequencing. In parallel, we studied oxidative phosphorylation and glycolysis and analysed active and repressive epigenetic modifications during blastocyst formation and expansion. We generated a transcriptomic, epigenetic, and metabolic map of the pluripotency continuum in rabbit preimplantation embryos and identified novel markers of naive pluripotency that might be instrumental for deriving naive pluripotent stem cell lines. Although the rabbit is evolutionarily closer to mice than to primates, we found that the transcriptome of rabbit epiblast cells shares common features with that of humans and non-human primates. Summary Statement Rabbit preimplantation embryos share characteristics with human and monkey embryos with respect to timing of early lineage segregation and expression of marker genes for naive and primed pluripotency
EXPECTATION OF STAKEHOLDERS ON FUTURE MANAGEMENT OF PONDS LANDSCAPES IN EUROPE
No full textInternational audienc
Ten steps to achieve the european green deal (Policy brief)
No full textThe European Green Deal is a monumental step in achieving a greener and more sustainable Europe, filled with promising targets which aim to culminate in no net emissions of greenhouse gases by 2050 and economic growth decoupled from resource use. It establishes great potential for a fairer economy, the revitalisation of rural areas and sustainability. Yet, the roadmap on how to actualise such targets has yet to be realised.This policy brief provides a roadmap, by giving recommendations for 10 concrete steps that can be taken to achieve the European Green Deal through agroecology, especially the Biodiversity and Farm to Fork Strategies. It will focus on many of the technical aspects, as well as on research, social responsibilities and responsible governance. Each step is to be considered as a whole, rather than individually, as many steps require the other in order to create true transformation
Contribution of cacao agroforestry versus mono-cropping systems for enhanced sustainability. A review with a focus on yield
No full textInternational audienceThe demand for cocoa has increased over the past years following the growth of cocoa-based products linked to the rise in living standard in highly populated countries. Cacao industry is therefore currently facing the dilemma of producing more cacao while ensuring its sustainability. Cacao monocrops and agroforestry systems (AFS) are two contrasting ways to produce cocoa, yet their impact on yields, contribution to farmer livelihood, cocoa quality remains understudied. Therefore, we reviewed existing literature comparing monocrop cacao farming systems with simple or complex AFS. We found 19 comparisons of the cocoa yields in monocrops and simple AFS and 20 comparisons of monocrop and complex AFS. Three main research findings derive from this work. First, in about one third of cases, cacao trees yield more (or equally) in AFS than in monocrops. However, when considering only simple AFS, cacao trees yield more or equal to cacao monocrop in 52% of the cases. Second, cocoa AFS yields an average of 14% less than cacao monocrop. Yet, on average simple AFS yielded 2% less than cacao monocrops. Finally, there are too little elements to draw conclusions about the nexus between cocoa quality and cacao tree cultivation system
Should and will “cultured meat” become a reality in our plates?
No full textInternational audienceProduced from proliferating cells in bioreactors with a controlled culture medium, “cultured meat” has been presented by its supporters, who are mainly private actors (start-ups), as a sustainable solution to meet the growing demand for animal proteins without weaknesses of animal husbandry in terms of environmental impact, animal welfare or even health. The aim of this chapter is to take stock of current knowledge on the potential benefits and pitfalls of this novel product. Since robust scientific arguments are lacking on these aspects, there is no consensus on the health and nutritional qualities of “cultured meat” for human consumption and on its potential low environmental impact. In addition, many issues related to the market, legislation, ethics and consumer perception remain to be addressed. The way in which this new product is regarded appears to be influenced by many factors related mainly to its price, as well as to the perception of safety, sensory traits but also environmental and nutritional issues. Therefore, research by universities and public research institutes indicates that “cultured meat” production does not present any major advantages in economic, nutritional, sensory, environmental, ethical or social terms compared to conventional meat. Thus, a more balanced diet by diversifying our sources of plant and animal proteins, consuming other meat substitutes, and reducing food losses and waste appear to be more effective short-term solutions to the urgent need of producing enough food for the growing human population (while reducing environmental degradation and animal suffering)
Itérations entre cadre théorique et données de terrain : quand la géographie aborde l'agriculture et le fonctionnement écologique des paysages
No full textInternational audienceThèse soutenue en 2020. L’action publique française inclut, depuis 2007, la question de la biodiversité dans une politique d’aménagement à travers la stratégie Trame Verte et Bleue qui met l’accent sur le déplacement des espèces et propose une approche intégrative de la conservation de la biodiversité. Cette politique concerne l’ensemble du territoire et intègre donc les espaces agricoles, y compris ceux où l’agriculture qualifiée d’intensive est souvent jugée contraire aux objectifs de préservation de la biodiversité. Comment, dès lors, les différents acteurs concernés peuvent-ils proposer une gestion durable de ces espaces agricoles en faveur des fonctionnalités écologiques du paysage ? Pour répondre à cette problématique, j’ai cherché, dans ce travail de thèse, relevant de la géographie de la conservation, à saisir la complexité des relations entre dimensions sociales et écolo-giques. Mobilisant un cadre d’analyse de la durabilité des systèmes socio-écologiques, j’ai développé tout au long du doctorat un Itinéraire méthodologique se nourrissant à la fois du regard théorique et de sa confrontation aux réalités du terrain. L’Itinéraire méthodologique s’articule autour de quatre échelles allant du national à l’exploitation agricole en passant par la région et le territoire. Afin de s’adapter à ces échelles, j’ai utilisé pour chacune d’entre elles, des méthodes, outils et données différents, tout en gardant pour objectif de les faire dialoguer. L’Itinéraire a également évolué dans le temps et s’est enrichi théoriquement et méthodologiquement au fur et à mesure, selon les données de terrain. C’est donc par une confrontation évolutive entre données de terrain et cadres théoriques mobilisables que l’Itinéraire méthodologique m’a permis de saisir la complexité des relations socio-écologiques dans la conservation de la biodiversité au sein d’un espace agricole