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Rénovation et/ou reconstruction urbaine : planification et métamorphoses de l’espace nîmois
No full textInternational audienceLa ville de Nîmes offre trois exemples caractéristiques de rénovation/reconstruction urbaine. Bien que non réalisés, trois plans d’ordonnancement de l’espace appartenant à trois époques historiques - le XVIIIe siècle, la Libération et le milieu des années 1990 – ont marqué de leur empreinte les transformations du tissu urbain. Le Plan Raymond (1785), dû à l’architecte royal du Languedoc, le plan Chouleur (1945) du nom d’un architecte nîmois influencé par la démarche des Congrès internationaux d’architecture moderne (CIAM), et le projet « Vers une ville sans banlieues, Expérience Nîmes » (1993), vision entrepreneuriale de la ville, ont produit un effet de réel sur la morphologie, jusqu’à déterminer les opérations contemporaines d’urbanisme, en cours ou envisagées
The silence of horses: Equine welfare and well-being through the eyes of those who live and work with them
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Muscle regeneration is improved by hot water immersion but unchanged by cold following a simulated musculoskeletal injury in humans
No full textInternational audienceCryotherapy is a popular strategy for the treatment of skeletal muscle injuries. However, its effect on post-injury human muscle regeneration remains unclear. In contrast, promising results recently emerged using heat therapy to facilitate recovery from muscle injury. This study aimed to examine the effect of three different thermal treatments on muscle recovery and regeneration following a simulated injury in humans. Thirty-four participants underwent a muscle damage protocol induced by electrically stimulated eccentric contractions triggering regenerative processes following myofibre necrosis. Thereafter, participants were exposed to daily lower body water immersion for 10 days in cold (CWI, 15 min at 12 degrees C), thermoneutral (TWI, 30 min at 32 degrees C) or hot water immersion (HWI, 60 min at 42 degrees C). Muscle biopsies were sampled before and at +5 (D5) and +11 (D11) days post-damage. None of the water immersions differed in recovery of force-generating capacity (P = 0.108). HWI induced a lower perceived muscle pain than TWI (P = 0.035) and lower levels of circulating creatine kinase (P <= 0.012) and myoglobin (P < 0.001) than TWI and CWI. Contrary to our hypothesis, CWI did not improve perceived muscle pain or reduce circulating markers of muscle damage (P >= 0.207). Expression of heat shock proteins 27 and 70 was significantly increased in HWI (P < 0.038) at D11 and appeared blunted using CWI. Furthermore, nuclear factor-kappa B expression significantly increased in all conditions except HWI, while interleukin-10 was upregulated only in HWI at D11 (P = 0.014). In conclusion, our results support the use of HWI but not cold, to improve muscle regeneration following an injury
Quelques réflexions autour de la disparition de l'agriculture en Cyrénaïque médiévale (XIe-XVe siècles)
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Probing Bacterial Interactions with the Schistosoma mansoni-Killing Toxin Biomphalysin via Atomic Force Microscopy and Single Molecule Force Spectroscopy
No full textInternational audienceRecent work has identified biomphalysin (BM) protein from the snail Biomphalaria glabrata as a cytolytic toxin against the Schistosoma mansoni parasite. Ex vivo interactome studies further evidenced BM’s ability to bind bacterial outer membrane proteins, but its specific antibacterial mechanisms and selectivity remain unclear. Accordingly, this study aims to elucidate the interaction between BM and two model bacteria with distinct cell surface architectures: Escherichia coli (Gram−) and Micrococcus luteus (Gram+). Employing a multiscale approach, we used in vivo single-molecule force spectroscopy (SMFS) to probe molecular interactions at the single cell level. Combined with cell aggregation assays, immunoblotting and Atomic Force Microscopy (AFM) imaging, SMFS results evidenced a selective interaction of BM from snail plasma with M. luteus but not E. coli. Exposure of M. luteus to BM compromised cell surface integrity and induced cell aggregation. These effects correlated with a patch-like distribution of BM on M. luteus reminiscent of pore-forming toxins, as revealed by the anti-BM antibody-functionalized AFM tip. Overall, this work highlights the utility of SMFS in dissecting host–pathogen molecular dialogs. It reveals BM’s selective action against M. luteus, potentially via surface clustering, and it shows spatially heterogeneous responses to the toxin within and between individual cells
Tannin with sodium carbonate: A single additive for poured earth concrete with tropical soils
No full textInternational audienceBuilding sustainable earth construction to replace cement concrete is a major challenge in fast-developing tropical regions. Poured earth, shaped like concrete, offers a cost-effective and eco-friendly alternative. Poured earth usually relies on industrial dispersants and hydraulic binders to fluidify and solidify the soil paste. However, these additives strongly increase environmental costs. Recent studies have highlighted the potential of tannins, which are organic extracts from wood, as an eco-friendly alternative. In particular, tannins combined with iron oxides can fluidify soils at an elevated pH, and chemical reactions between tannins and iron oxides lead to rapid solidification, enabling rapid unmolding and improving water resistance. Tropical soils naturally have a high iron oxide content. This study investigated whether tannins could react with the iron oxides naturally present in tropical soil and be used as a single additive for poured earth. Optimal reactions between soils, tannins and iron oxides require an elevated soil pH, and tannins were combined with sodium carbonate (Na2CO3), a low-cost, eco-friendly alkali. Mortars prepared with different dosages of tannin+Na2CO3 were tested and compared to the industrial dispersant sodium hexametaphosphate (NaHMP), using three tropical soils from French Guiana. Results showed that both tannin+Na2CO3 and NaHMP could fluidify the three soils, improved mechanical strength and water resistance, and reduced initial water content and shrinkage. However, tannin+Na2CO3 induced faster solidification, which was attributed to the formation of ferric tannate observed by infrared spectroscopy (ATR-FTIR). This study paves the way for designing poured earth with tropical soil using a single, largely bio-sourced additive: tannin+Na2CO3
The contributions of coastal small-scale fisheries toward the sustainable development goals: a Kenyan Case Study
No full textInternational audienceSmall-scale fisheries (SSFs) contribute significantly to the economies of coastal developing nations, offering employment and food, and supporting sustainable development goals (SDGs). Despite increasing focus on SSFs, data, and knowledge gaps persist in SSFs research and their contribution to SDGs. Ten fisheries were assessed in Kenya for their contributions to 12 SDGs, highlighting different levels of contributions. Small pelagic and shrimp fisheries display higher overall contributions to SDGs, appearing to perform strongly in more SDGs, while handline and octopus fisheries display lower contributions to SDGs. Specific contributions can vary depending on the characteristics of individual fisheries, such as their structures and markets. This study provides valuable insights from an underrepresented part of the world on the under-researched topic of SSFs and SDGs. It also contributes significantly to research on sustainable development in developing coastal nations and highlights gaps and areas for improvement in achieving the SDGs within the context of SSFs
A review of biomass thermochemical gasification: Toward solar hybridized processes for continuous and controllable fuel production
No full textInternational audienceGasification of carbonaceous feedstocks into value-added syngas is a mature chemical process, developed at industrial scale for the production of chemicals and liquid fuels. Biomass gasification could open the path toward renewable fuel production, waste valorization, and carbon capture, but a fraction of the initial feedstock is burnt for process heat. Hence, allothermal solar heating is an attractive option for a clean and efficient production of syngas, enabling solar energy storage under a chemical form. Solar gasification potentially converts the whole feedstock mass while the produced syngas is not contaminated by combustion by-products and the high temperatures help to ensure high syngas yields with minimized char and tars production. Such results were however obtained under favorable solar power input conditions. In practice, the solar power fluctuations and intermittency must be managed carefully, with a control of the reactor inputs round the clock for stable syngas production. This review aims to provide a state-of-the-art on the variety of scientific topics involved in developing a stable and controllable solar gasification process, and it further addresses the challenges of hybridized solar-autothermal processes. Conventional gasification is first tackled, unraveling the historical background and current applications of the process. Associated chemical mechanisms are described, with some modeling considerations. Concentrated solar power technologies are then described, with a focus on thermochemical applications and existing solar gasification technologies. Finally, the methods to smoothen the effects of fluctuating solar power availability on solar syngas production are assessed, including thermal heat storage and solarautothermal hybridization for continuous day-night operation. The implementation of dynamic control methods is addressed, to assess the practical application of control strategies, paving the way toward continuous solar fuels production.</div