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Microwave-assisted desorption of CO<sub>2</sub> from ethanolamine solvent in a porous hollow fiber membrane - numerical modeling
No full textInternational audienceIn our previous work, microwave regeneration of 30 wt. % ethanolamine solvents in a hollow fiber gas-liquid contactor was studied. In this system, the solvent was heated by microwaves as it traversed a microwave applicator while passing through the lumen of the hollow fiber. Experimental results do not provide insight into the operation of microwave regeneration. The aim of this study is therefore to develop a model to simulate the microwave solvent regeneration in the single fiber system.The numerical approach is based on coupling 3D microwave heating of solvent flow, and 1D chemical desorption of CO2 applicable to non-isothermal conditions along the fiber. The model was successful in reproducing with reasonable accuracy the global desorption data from the regeneration experiments, assuming a low wetting fraction of the membrane. The effects of operating conditions were explored: results show that increasing the solvent flow rates induces higher temperature gradients at the boundary of the fiber lumen thus increasing desorption rates. It has been found that increased fiber radius leads to better desorption rates at the expense of lowering the interfacial surface density. On another note, numerical results show that isothermal regeneration performs better than microwave mode although the latter is able to outperform where hotspots persist along the fiber. With regards to flow configurations during microwave regeneration, counter-current mode performed better than co-current one: the sweeping gas in the former mode passes from the hot solvent side to the cold solvent side which encourages reabsorption of the desorbed CO2
Étude des mesures de biosécurité dans la pratique vétérinaire bovine : enquête auprès d'un échantillon de vétérinaires et réalisation d'un guide pratique
No full textLa biosécurité correspond à l’ensemble des mesures prises pour éviter l’introduction, le développement et la propagation de maladies infectieuses ou provoquées par des agents biologiques. Il s’agit donc d’une notion centrale dans le métier de vétérinaire, à plus forte raison lorsque celle-ci s’exerce à l’échelle de l’individu mais aussi des populations, c’est-à-dire d’un troupeau. En effet, dans le cadre de la pratique bovine, les vétérinaires sont les interlocuteurs privilégiés des éleveurs concernant ces mesures au sein de leur élevage. Le sujet est devenu d’autant plus central que de nouvelles maladies aux conséquences lourdes de sens ont émergé sur le territoire français, contre la propagation desquelles, se bat toute la profession. Cette étude a pour objectif de faire une description des mesures de biosécurité mises en place sur le terrain par les vétérinaires en clientèle bovine. Pour ce faire, un questionnaire a été envoyé, interrogeant sur les habitudes de nettoyage et de désinfection d’une diversité d’objets mais aussi sur les raisons freinant la mise en place de telles mesures. Les réponses à l’enquête ont mis en lumière une disparité importante des protocoles de nettoyage et de désinfection, ainsi que de leur fréquence de leur mise en œuvre. Aucune corrélation n’est visible avec la description succincte des cliniques apportée par les réponses aux premières questions du questionnaire. Mais les freins mentionnés sont, quant à eux, souvent les mêmes : un manque d’infrastructures proposées par les éleveurs ou de mauvaises conditions rencontrées dans les élevages mais aussi un manque de temps. La rédaction de fiches techniques très rapides à prendre en main est donc pertinente, apportant quelques clés d’utilisation, notamment des désinfectants
Development of a health-related questionnaire for quality-of-life assessment in dogs with chronic enteropathy
No full textInternational audienceAbstract Background Chronic enteropathies (CEs) in dogs substantially impact the quality of life (QoL) for both patients and owners. Existing clinical indices do not capture the broader burden of disease, and no validated health-related QoL (HRQoL) tool exists for CE. Hypothesis/Objectives Develop and validate a psychometrically sound HRQoL questionnaire for dogs with CE. Animals A total of 351 client-owned dogs: 141 with CE, 126 healthy, and 84 with other chronic diseases (OCD), based on owner classification. Methods A multi-phase psychometric study was conducted to create and validate the instrument. Items were generated from literature and expert input, refined using cognitive debriefing and statistical filtering, and tested for internal consistency, construct validity, and discriminative validity. The HRQoL scores were compared among groups and analyzed for demographic factors. Results The final Canine Chronic Enteropathy QoL (CCEQoL) questionnaire included 33 items. Internal consistency was excellent (Cronbach’s α = 0.91). The median total score (TS) was higher in CE dogs (129; interquartile range [IQR], 73.5–181.5) than in OCD dogs (62; IQR, 31.3–105.4) and healthy dogs (15.3, IQR, 6–34; P < .001). The total score was inversely correlated with owner-rated overall QoL (ρ = −0.61; P < .001). In CE dogs, the TS was weakly and inversely correlated with age but was not significantly associated with breed size, comorbidities, or country of residence. Conclusions and clinical importance The CCEQoL is the first validated HRQoL tool for dogs with CE. It provides a structured, multidimensional assessment of disease burden and may enhance patient-centered care, owner–veterinarian communication, and clinical research
Dose- and genotype-dependent cardiac arrhythmia and sudden death in rats following microdystrophin gene therapy
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Selective culling and the potential persistence of lumpy skin disease in cattle herds: insights from a mechanistic transmission model
No full textInternational audienceThe first epidemic of lumpy skin disease (LSD) in France started in June 2025, with a total of 117 outbreaks recorded. This vector-borne disease affecting cattle is highly contagious, and prompted the implementation of strict control measures, including total depopulation of affected herds, resulting in the culling of more than 3,500 cattle. During the epidemic, total depopulation measures became increasingly unacceptable to cattle farmers, as they were perceived as unnecessary, leading to major protests. We use mathematical models to compare within-herd transmission dynamics under a selective culling strategy versus total depopulationIn this work, we propose a compartmental model of within-herd transmission, accounting for both cattle and vector populations. A test-and-cull strategy is implemented, relying on imperfect diagnostic tests capable of detecting infection in asymptomatic cattle, and different levels of test sensitivity and detection earliness are investigated. Alongside the test-and-cull strategy, a vector control strategy is implemented considering different levels of effectiveness in reducing the vector population.Our model shows that a selective culling strategy still results in 75% [26, 100] of the herd becoming infected, even in the best-case-scenario with highly efficient diagnostic tests and vector control. Given currently available tests, considered to have a sensitivity of 30% for subclinical animals within 2-3 days prior to their infectiousness onset, the predicted persistence is 60 days [34, 95], with 94% of the herd [44, 100] eventually becoming infected, representing only a marginal advantage compared with a total depopulation strategy. These metrics further deteriorate when the efficacy of insecticide products decreases
Development of a numerical model for measuring the electrical conductivity (EC) of a cake batter
No full textInternational audienceThe electrical conductivity (EC) of materials represents their ability to conduct electrical current and determines the power dissipated within the material. This parameter can be temperature and electric field dependent. When EC is measured in the electric fields used for ohmic heating, the increase in temperature results in heating nonuniformity in the measuring cell. As a result, the relationship between EC and temperature cannot be accurately determined. In addition, for cake batter, starch gelatinization occurs during the measurement, leading to more complex EC curves. To address these issues, this study proposes a numerical method for determining EC that accounts for temperature non-uniformity. This model is coupled with a starch gelatinization model. The principle is based on the estimation of the EC using the method of least squares between the experimental temperature and the numerical one. The estimation of the EC of the cake batter consists of two steps: first, the device was characterized with xanthan and potassium chloride solutions of known electrical conductivities. A conversion efficiency of 0.77 was found. This efficiency was used to estimate the EC of the cake batter as a function of temperature and for different electric fields. Results showed that EC became independent of the electric field from 34.57 V/cm
Transfert de chaleur conjugué conduction–rayonnement de gaz non gris dans une chambre de combustion 2D à l’aide de la méthode de lancer de rayons et du modèle corrélé SLW.
No full textInternational audienceThe present study examines combined conduction-radiation heat transfer in non-gray gases within a twodimensional rectangular domain, representing a section of a combustion chamber. The participating gases considered are 10%CO 2 /N 2 , 20%H 2 O/N 2 and their corresponding mixture, whereas N 2 is treated as nonparticipating. A correlated SLW model is developed to evaluate the Planck-mean absorption coefficients by summing the products of discrete gray absorption coefficients and their associated weights. The radiative properties of the non-gray gases are obtained over their absorption spectral bands using data from HITEMP2010, while thermal conductivities are computed using the Sutherland relation. An exact semi-analytical formulation based on ray tracing, Bickley-Naylor functions, and Gauss quadrature is employed to solve the radiative transfer equation (RTE) using Planck-mean absorption coefficients. The energy equation is discretised using a finitedifference approach with a Crank-Nicolson scheme. The effects of gas thermal properties, gas temperature, the number of discrete gray gases, gas species, and mixture ratios on thermal quantities are analysed in detail. Numerical simulations of dimensionless conduction-radiation temperature and total heat flux are presented.La présente étude examine le transfert de chaleur conjugué conduction–rayonnement dans des gaz non gris à l’intérieur d’un domaine rectangulaire bidimensionnel, représentant une section d’une chambre de combustion. Les gaz participants considérés sont des mélanges 10 % CO₂/N₂, 20 % H₂O/N₂ ainsi que leur mélange correspondant, tandis que le N₂ est traité comme non participant. Un modèle corrélé SLW est développé afin d’évaluer les coefficients d’absorption moyens de Planck par sommation des produits des coefficients d’absorption gris discrets et de leurs poids associés. Les propriétés radiatives des gaz non gris sont obtenues sur leurs bandes spectrales d’absorption à partir des données HITEMP2010, tandis que les conductivités thermiques sont calculées à l’aide de la relation de Sutherland. Une formulation semi-analytique exacte, basée sur la méthode de lancer de rayons, les fonctions de Bickley-Naylor et la quadrature de Gauss, est utilisée pour résoudre l’équation du transfert radiatif (ETR) en employant les coefficients d’absorption moyens de Planck. L’équation de l’énergie est discrétisée selon une approche aux différences finies avec un schéma de Crank-Nicolson. Les effets des propriétés thermiques des gaz, de la température du gaz, du nombre de gaz gris discrets, des espèces gazeuses et des rapports de mélange sur les grandeurs thermiques sont analysés en détail. Des simulations numériques de la température adimensionnelle conjuguée conduction–rayonnement et du flux thermique total sont présentées
Expanding the application of the TAIL rating scheme to schools: schoolTAIL
No full textInternational audienceSchools have no universally adopted scheme for rating indoor environmental quality (IEQ). In this work, we adapted the TAIL rating scheme that was developed for assessing IEQ in offices and hotels so that it can be used in schools. The original TAIL scheme assesses thermal, acoustic, and luminous conditions, along with indoor air quality, using ten measured parameters and one evaluated through observation and one through simulation. We supplemented it with two other parameters, reverberation time and the concentration of nitrogen dioxide, to adequately characterize a classroom's IEQ. We have also updated the ranges for PM2.5 in accordance with the latest updates to the WHO air quality guidelines. Otherwise, we kept the principles used to develop the original TAIL rating scheme unchanged. We used measurements from schools reported in the published literature to identify the relevant parameters. We refer to the newly developed scheme as TAIL for schools, in short, schoolTAIL. We examined its feasibility using an existing database, with measurements made in 308 randomly selected schools as part of a nationwide survey in France. The new scheme turned out to be a valuable tool for identifying potential problems and prioritizing IEQ remediations, providing a comprehensive yet easy-tounderstand overview of the current situation in school buildings
Coupling of electrochemical systems with nature-based solution for wastewater treatment: A comprehensive review to evaluate the synergy, efficacy and applicability
No full textInternational audienceThis paper critically reviews for the first time electrochemical-assisted nature-based solution (NBS) systems applied for wastewater treatment. Such coupling could be a more sustainable response to address the water issues through the Sustainable Development Goals (SDGs) from the United Nations. Eight electrochemical/NBS systems combinations have been identified in the literature: (i) electro-coagulation (EC)/electro-oxidation (EO)-constructed wetland (CW), (ii) microbial fuel cell (MFC)-CW, (iii) bio-electrochemical system (BES)-CW, (iv) electrokinetic (EK)-phytoremediation (PR), (v) MFC/EC-vermi filtration (VF), (vi) electro-Fenton (EF)-algal pond (AP), (vii) electrochemical disinfection (ED)/ICME-soil infiltration, and (viii) SI/green wall (GW). The main principles, mechanisms and parameters have been critically reviewed, as well as the synergies gained through such coupling. Still, challenges remained to be solved. The matrix effect during electrochemical treatment could induce toxicity of the treated solution before NBS remediation, which remained underexplored. In addition, the mechanisms involved in the NBS systems are still not fully clarified, meaning that the process control is not easy to implement due to difficulties in getting predictive modelling. A few recommendations concern the need to develop suitable electrochemical designs, such as microfluidic devices, particularly adapted to low-conductivity effluent to avoid the addition of supporting electrolyte. Future work should experimentally validate low-energy electrosorption-based processes in combination with NBS
Inhibitory effects of terpenes on Sarcoptes scabiei in the molting stage
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