Portail HAL ONIRIS VetAgroBio Nantes
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Pressure Drops for Turbulent Liquid Single-Phase and Gas–Liquid Two-Phase Flows in Komax Triple Action Static Mixer
No full textInternational audienceStatic mixers are commonly used for process intensification in a wide range of industrial applications. For the design and selection of a static mixer, an accurate prediction of the hydraulic performance, particularly the pressure drop, is essential. This experimental study examines the pressure drop for turbulent single-phase and gas–liquid two-phase flows through a Komax triple-action static mixer placed on a horizontal pipeline. New values of friction factor and z-factor are reported for fully turbulent liquid single-phase flow (11,700 ≤ ReL ≤ 18,700). For two-phase flow, the pressure drop for stratified and intermittent flows (0.07 m/s ≤ UL ≤ 0.28 m/s and 0.46 m/s ≤ UG ≤ 3.05 m/s) is modeled using the Lockhart–Martinelli approach, with a coefficient, C, correlated to the homogenous void fraction. Conversely, the analysis of power dissipation reveals a dependence on both liquid and gas superficial velocities. For conditions corresponding to intermittent flow upstream of the mixer, flow visualization revealed the emergence of a swirling flow in the Komax static mixer. It is interesting to note that an increase in slug frequency leads to an increase, followed by stabilization of the pressure drop. The results offer valuable insights for improving the design and optimization of Komax static mixers operating under single-phase and two-phase flow conditions. In particular, the reported correlations can serve as practical tools for predicting hydraulic losses during the design and scale-up. Moreover, the observed influence of the slug frequency on the pressure drop provides guidance for selecting operating conditions that minimize energy consumption while ensuring efficient mixing
Étude comparative de la douleur per et post opératoire lors de deux techniques de dilacération musculaire lors d'une ovariectomie par les flancs chez la chienne
No full textLa stérilisation est une procédure vétérinaire standard dont les premières applications remontent au XIXᵉ siècle. Depuis, les techniques ont considérablement évolué, offrant aux vétérinaires plusieurs approches se-lon les objectifs recherchés : réduction du temps opératoire, diminution des complications, ou encore amélio-ration du confort animal. Le choix de la méthode dépend notamment des moyens disponibles et du contexte d'intervention. Cette étude s’intéresse à la stérilisation des chiennes par la voie d’abord par les flanc, en comparant deux techniques de dilacération musculaire : une dilacération plan par plan, et une ouverture des trois plans mus-culaires en une seule fois par trocardage à l’aide d’un clamp à bout arrondi. 43 chiennes ont été stérilisées dans notre étude, réparties entre les deux techniques précitées. L’objectif principal était d’évaluer l’impact de ces deux approches sur la douleur ressentie par l’animal, tant per-opératoire qu’en post-opératoire immédiat et différé. Pour cela, des paramètres physiologiques (dont la pression artérielle) ont été surveillés durant l’intervention, et une grille d’évaluation de la douleur (Glasgow) a été utilisée après la chirurgie. Les résultats n’ont pas mis en évidence de différence significative en termes de douleur post-opératoire entre les deux techniques. Ce-pendant, les variations observées de la fréquence cardiaque et de la pression artérielle pendant l’opération suggèrent une sensibilité accrue lors du trocardage. En résumé, la technique de trocardage apparaît comme une alternative viable, notamment pour réduire le temps chirurgical. Elle nécessite toutefois une attention particulière concernant la gestion de la douleur pero-pératoire afin de garantir le bien-être de l’animal
Évaluation de la formation vétérinaire pour les gestes techniques de prélèvement en médecine des animaux de compagnie à Oniris VetAgroBio Nantes : enquête auprès des étudiants en fin de formation initiale et après un an de pratique professionnelle
No full textLa formation pratique constitue l’un des piliers centraux du cursus vétérinaire. Pourtant, les étudiants des quatre écoles vétérinaires françaises rapportent un manque d’opportunités de mise en pratique, ainsi qu’une inquiétude quant à leurs compétences cliniques futures. Par ailleurs, l’enseignement des gestes de prélèvement reste peu documenté et non standardisé, chaque école développant ses propres méthodes pédagogiques et évaluatives. Le niveau réel de maîtrise en fin de formation reste donc incertain. La première partie de cette thèse propose une synthèse bibliographique sur la formation aux gestes techniques dans les écoles vétérinaires. Nous avons choisi de concentrer notre travail sur les gestes de prélèvement, qui font ensuite l’objet d’une description détaillée, abordant leurs indications, le matériel requis, les étapes pratiques et les difficultés rencontrées. Un parallèle est également établi avec les méthodes d’enseignement spécifiquement mises en place à Oniris VetAgroBio Nantes. La seconde partie présente deux enquêtes : la première menée auprès de 36 étudiants de la promotion 2019-2024 en dernière année à Oniris VetAgroBio, en filière animaux de compagnie, et la seconde auprès de 28 d’entre eux un an plus tard. Elles ont pour objectif d’évaluer leur niveau de maîtrise sur les gestes de prélèvement en fin de formation initiale puis après une année de pratique professionnelle, ainsi que d’identifier les principaux freins rencontrés dans l’acquisition de ces compétences
Application d’une démarche d’amélioration continue centrée autour du Nettoyage En Place en fromagerie industrielle
No full textA continuous improvement approach was implemented in three parts. The first part focuses on consumption and CIP functioning optimization. This has been done by daily tracking and analysis of the cleanings, which lead to a decrease in the frequency of non-compliant cleanings. A particular effort was put towards the reduction of water consumption during rinsing, resulting in a significant decrease of water consumption by more than 6%.Secondly, the agents working with the CIP equipment were trained to apply good practices relevant to the structure, which improved the workflow, saved time, and reduced unnecessary cleanings. Meanwhile, a qualification of all the cleanings was performed.Finally, raw material wastes were mapped and studied, opening the way to some promising leads for saving raw materials.Une démarche d’amélioration continue centrée autour du NEP à été mis en place en 3 parties. La première partie traite de l’optimisation des consommations et du fonctionnement du NEP. Cela se fait notamment par le suivit et l’analyse quotidien des lavages qui amène à une diminution du taux de non-conformité, ainsi que par la réduction des volumes de rinçages, amenant à des réductions significatives des consommation d’eau de plus de 6%. Dans un deuxième temps la formations des acteurs du NEP aux bonnes pratiques d’utilisation à permit d’améliorer le fonctionnement de l’installation, de gagner du temps et de diminuer les lavages inutiles. En parallèle une qualification de l’intégralité des lavages à été menée. Enfin une cartographie et une étude des pertes matières a été réalisé, ouvrant la réflexion sur des pistes très prometteuse en terme de gain de matière première
Running the Risk: Road‐Crossing Behavior in Wild Chimpanzees (Pan troglodytes) in an Anthropogenic Habitat in Uganda
No full textInternational audienceRecent research highlights the behavioral flexibility of wild chimpanzees in response to human‐induced changes in their environment, including agricultural and infrastructural development. The expansion of road networks threatens chimpanzee populations across Africa. Studying their road‐crossing behavior, especially outside protected areas where road impacts are greatest, helps identify factors influencing their choices and flexibility. This study seeks to gain a deeper understanding of how chimpanzees navigate busy roads and assess the danger posed by roads. Such insights are needed to develop effective conservation strategies in regions facing escalating human impact, including recommendations for the design and management of traffic on existing and future roads. Using a dataset of 129 video‐recorded road crossings spanning 38 months, we analyzed the behavioral adjustments of chimpanzees in Bulindi, Uganda, when crossing a recently paved, busy main road within their home range. Using generalized linear mixed models, we investigated chimpanzee risk perception, protective and cooperative behaviors, vigilance, and progression order during road crossings. We identified variations in their behavior according to age‐sex of individuals, group composition, and level of risk. We found that Bulindi chimpanzees exhibit behavioral strategies to reduce risks of collision or close encounters with humans on the road, as previously described. However, they were less vigilant than expected. We suggest that the chimpanzees have developed tolerance of the risks presented by the road, owing to their long history of crossing it before it was tarmacked and widened, and their familiarity with local people and motor traffic. Our results provide further evidence of the flexibility of wild chimpanzees. However, road crossings remain highly risky for large mammals like great apes, necessitating measures to mitigate the impact of road development on this and other endangered species (e.g. speed bumps, police enforcement, public awareness raising)
Flatbread and consumers from the Mediterranean area: preference, perception, and innovation acceptance
No full textInternational audienceThe FLAT BREAD MINE international research project, funded by PRIMA with EU support, explores innovative technologies and reformulations to develop healthy flatbreads for Mediterranean consumers. A survey across eight Mediterranean countries examined consumption habits, preferences, perceptions, and openness to innovation. Statistical analyses, including logistic and linear regressions, and principal component analysis (PCA), were applied. PCA identified three distinct consumer segments: Mindful (34 %), Aesthetic (32 %), and Practical (34 %), prioritizing nutrition, sensory qualities, and convenience, respectively. The Mindful group showed the strongest interest in innovation, positioning them as the primary target group for project outcomes. Geographic origin strongly influenced preferences: Middle Eastern consumers favoured double-layered flatbreads and considered them essential, while Europeans preferred single-layered types for their gastronomic and health appeal. Pita was the most popular variety (45.9 %). Taste and texture were major drawbacks of gluten-free flatbreads. Part-baked flatbreads were seldom consumed (~16 %) largely due to misconceptions, though interest was higher for shelf storage (40.6 %) than for frozen (24.8 %). The most accepted alternative flours were durum wheat (59.7 %), corn (53.1 %), and oat (53 %). Overall, the study enhances understanding of flatbread preferences in the Mediterranean area, underscoring the importance of cultural origin and consumer attitudes in driving innovation in the flatbread industry
Is it possible to valorize bicarbonates from reclaimed wastewater by CO2 electroreduction into formic acid? Investigation under low bicarbonate concentration and low-conductivity solutions
No full textInternational audienceThe electroreduction of CO 2 into value-added compounds from low bicarbonate concentration solutions typical of treated wastewater has been explored for the first time, unlike existing studies that focus on high bicarbonates concentrations and pressurized gas CO 2 as sources.This study investigates the feasibility of producing formic acid (FA) from low initial total inorganic carbon (TIC 0 ) concentration referring to total inorganic carbon (TIC) after acidification to pH 4 (15-50 mg-C L -1 ) under microfluidic conditions in a filter press cell, from simulated to real reclaimed wastewaters. The effect of TIC 0 demonstrated that an optimal TIC 0 of 20 mg-C L -1 at j app = 5 mA cm -2 balanced the conversion yield (56%), faradaic efficiency (FE) (9%), and specific energy consumption (E sp ) (1.96 kWh mol CO 2 -1 ).Reducing the j app from 5 to 2 mA cm -2 resulted in a 14% increase in FE, although accompanied by a decrease in an overall conversion efficiency, highlighting the compromise that exists between selectivity and productivity. A kinetic model based on TIC degradation and FA formation accurately captured experimental trends. Results from real effluents showed successful FA production.These findings highlighted the interdependence between mass transport (k m ) limitations, TIC availability, and competing reactions such as hydrogen evolution reaction (HER). The observed variations in k m (1.4-1.6 × 10 -5 m s -1 ) indicated that mass transport constraints played a critical role in CO 2 reduction efficiency, where an increased diffusion layer ( ) at higher TIC 0 limited CO 2 availability to the cathode surface shifting the balance between CO 2 reduction and HER. FTIR analyses further revealed an intensification of FA bands with increasing current.</div
Fibromyalgia: do I tackle you with complementary medicines?
No full textInternational audienceRecent guidelines for managing fibromyalgia highlight the importance of a graded-care approach, tailoring treatment to predominant symptoms, and appropriately integrating nonpharmacological treatments and complementary medicine (CM). Many fibromyalgia patients turn to nonpharmacological treatment and CM for various reasons, including concerns about medication side effects and persistent symptoms despite pharmacological treatment. In addition, these approaches are sometimes mistakenly, but often, perceived as natural and, therefore, widely accepted as well-tolerated with minimal risks. However, as with many patients using CM, fibromyalgia patients frequently engage in these practices without informing their physicians, often because of fear of a negative reaction. This can occur in contexts that lack adequate safeguards, such as treatment by noncertified practitioners, undocumented practices, excessive costs, or unsafe environments. In this narrative review, we first provide updated definitions of these practices, discuss their potential benefits and associated risks, and explore the challenges in their evaluation. We then summarize key findings from the literature before proposing a structured approach for discussing these practices with fibromyalgia patients. This includes assessing their prior experiences, expectations, and motivations for long-term adherence. We also offer guidance on selecting qualified practitioners and ensuring a sufficiently safe treatment environment. Finally, we highlight essential "red flags" that pain specialists and health care providers should discuss with patients, emphasizing the need for caution or even discontinuation of certain practices when these warning signs are present