An Overview on the Use of Lignin and Its Derivatives in Fire Retardant Polymer Systems

Lignin is a highly abundant bio-polymeric material that constitutes cellulose one of major component in cell wall of woody plants. Alternatively, large quantity of lignin is yearly available from numerous pulping and paper industries; this is the key point that justifies its large use for industrial applications. Lignin could be one of the most essential and sustainable bio-resources as raw material for the development of environmentally friendly polymer composite. Owing to its huge chemical structure, lignin can provide additional functionality such as filler, reinforcing agent, compatibilizer, stabilizer, etc. In this study, the fire retardant functionality of lignin has been employed in polymeric materials. Due to high charring capability, lignin is effectively used as carbon source in combination with other flame retardants for designing the intumescent system for polymeric materials. Further in this, several articles related to lignin-based intumescent are reviewed and interesting work formulation as well as meaningful results achieved in the flame retardancy are discussed. More attention is given to the studies concerning the use of current intumescent systems for textile applications by means of coating on fabric/nonwoven and melt blending in bulk polymers

Modélisation en centrifugeuse du renforcement de sols compressibles par inclusions rigides : dispositifs du transfert de charge par cisaillement

Soft soils reinforced by vertical stiff piles are covered by a load transfer granularplatform in which arching occurs. By experiments on reduced –scale centrifuged model, the mechanisms of load transfer will be studied in a 3D arrangement. Several heights of load transfer platform will be tested to simulate embankment or floor slab. An original experimental device and the test programme are presented.Les sols compressibles renforcés par inclusions rigides verticales sont surmontés d’'un matelas granulaire de report de charge dans lequel se développent des transferts de charge par cisaillement. Via des essais sur modèle réduit centrifugé, les mécanismes de ces transferts vont être étudiés dans une configuration 3D pour différentes hauteurs de matelas, correspondant au cas d’ouvrages de type dallage ou remblai. Un dispositif expérimental original, en conception au LCPC, est présenté ainsi que le plan d’'expérience

Macrophage-B Cell Interactions in the Inverted Porcine Lymph Node and Their Response to Porcine Reproductive and Respiratory Syndrome Virus

Swine lymph nodes (LN) present an inverted structure compared to mouse and human, with the afferent lymph diffusing from the center to the periphery. This structure, also observed in close and distant species such as dolphins, hippopotamus, rhinoceros, and elephants, is poorly described, nor are the LN macrophage populations and their relationship with B cell follicles. B cell maturation occurs mainly in LN B cell follicles with the help of LN macrophage populations endowed with different antigen delivery capacities. We identified three macrophage populations that we localized in the inverted LN spatial organization. This allowed us to ascribe porcine LN MΦ to their murine counterparts: subcapsular sinus MΦ, medullary cord MΦ and medullary sinus MΦ. We identified the different intra and extrafollicular stages of LN B cells maturation and explored the interaction of MΦ, drained antigen and follicular B cells. The porcine reproductive and respiratory syndrome virus (PRRSV) is a major porcine pathogen that infects tissue macrophages (MΦ). PRRSV is persistent in the secondary lymphoid tissues and induces a delay in neutralizing antibodies appearance. We observed PRRSV interaction with two LN MΦ populations, of which one interacts closely with centroblasts. We observed BCL6 up-regulation in centroblast upon PRRSV infection, leading to new hypothesis on PRRSV inhibition of B cell maturation. This seminal study of porcine LN will permit fruitful comparison with murine and human LN for a better understanding of normal and inverted LN development and functioning

Catastrophic risk and risk management, what do we know about livestock epidemics? State of the art and prospects

The economic consequences of livestock epidemics have been long studied for purposes of estimating the costs of preventive and curative veterinary measures. In this paper, we show that this catastrophic risk may have wide market consequences, and that the risk management systems are quite limited to compensate long term impacts in the European context of growing trade. Through a detailed literature review, we present the main developments of the economic research aiming at highlighting the economic consequences of animal epidemics such as Foot and Mouth Disease. We acknowledge that a very few studies have focused on the economic dynamics and on the long-run effects occurring after an epidemic disease outbreak. We discuss the relevance of a dynamic approach to reveal that the de-structuring of livestock markets affects the production dynamics as well as the whole agricultural sector. Financial implications and market constraints remain poorly studied in the livestock epidemics literature. We emphasize the growing interest of a dynamic Computable General Equilibrium approach to reveal the overall effects of epidemic outbreaks on the whole economy. This innovative research raises important challenges for the assessment and implementation of risk management policie

Présentation

International audienc

La « crise » : circulation et fiction

International audienc

Contribution à l'étude de nouveaux ligands des récepteurs 5-HT4, 5- HT6 et 5- HT7 contenant le système pyrrolo[1,2-a]pyrazine

CAEN-BU Médecine pharmacie (141182102) / SudocLYON1-BU Santé (693882101) / SudocSudocFranceF

Imaginaire de la ponctuation. Ordre et inquiétude du discours

International audienc

Présentation

Bien davantage que la signification ou la fonction grammaticale, c’est l’histoire qui s’est sédimentée dans les signes de ponctuation et qui, figée et parcourue d’un léger frisson, jette un œil au-dehors par chacun d’entre-eux.Adorno, Mots de l’étranger et autres essais. Notes sur la littérature II C’est de cette sédimentation que traitera ce dossier sur quelques imaginaires de la ponctuation dans le discours littéraire depuis la fin du xixe siècle. Que vise-t-on par la notion d’« imaginaire ..