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• A flexible way of coupling independent fluid and solid solvers is proposed. • The coupling mechanism is based on a Python wrapping process. • Efficient ready-to-use coupling functionalities are available. • The environment was tested and validated on fluid-structure interaction benchmarks. CUPyDO, a fluid-structure interaction (FSI) tool that couples existing independent fluid and solid solvers into a single synchronization and communication framework based on the Python language is presented. Each coupled solver has to be wrapped in a Python layer in order to embed their functionalities (usually written in a compiled language) into a Python object, that is called and used by the coupler. Thus a staggered strong coupling can be achieved for time-dependent FSI problems such as aeroelastic flutter, vortex-induced vibrations (VIV) or conjugate heat transfer (CHT). The synchronization between the solvers is performed with the predictive block-Gauss-Seidel algorithm with dynamic under-relaxation. The tool is capable of treating non-matching meshes between the fluid and structure domains and is optimized to work in parallel using Message Passing Interface (MPI). The implementation of CUPyDO is described and its capabilities are demonstrated on typical validation cases. The open-source code SU2 is used to solve the fluid equations while the solid equations are solved either by a simple rigid body integrator or by in-house linear/nonlinear Finite Element codes (GetDP/Metafor). First, the modularity of the coupling as well as its ease of use is highlighted and then the accuracy of the results is demonstrated. [ABSTRACT FROM AUTHOR]

The Particle Finite Element Method (PFEM) is evaluated in the context of the numerical simulation of bird strike events. To assess the possibilities of the method, theoretical analyses are initially performed based on the impact of a water jet on a rigid surface. Then, the influence of the geometry of a more realistic projectile is analyzed and the capability of the method to take into account separation and fragmentation is highlighted. Finally, the method is tested for impacts against deformable targets, using a partitioned algorithm with dynamic relaxation for the fluid-structure interaction, combining the PFEM for the description of the bird with a non-linear Finite Element approach for the description of the impacted structure, which can undergo large plastic deformations. To assess the quality of the obtained results a series of numerical examples from the literature has been selected and used as a reference throughout the paper. Among the studies presented in this work also a novel numerical benchmark for the evaluation of bird impact simulations is proposed. [ABSTRACT FROM AUTHOR]

The Particle Finite Element Method (PFEM) is evaluated in the context of the numerical simulation of bird strike events. To assess the possibilities of the method, theoretical analyses are initially performed based on the impact of a water jet on a rigid surface. Then, the influence of the geometry of a more realistic projectile is analyzed and the capability of the method to take into account separation and fragmentation is highlighted. Finally, the method is tested for impacts against deformable targets, using a partitioned algorithm with dynamic relaxation for the fluid-structure interaction, combining the PFEM for the description of the bird with a non-linear Finite Element approach for the description of the impacted structure, which can undergo large plastic deformations. To assess the quality of the obtained results a series of numerical examples from the literature has been selected and used as a reference throughout the paper. Among the studies presented in this work also a novel numerical benchmark for the evaluation of bird impact simulations is proposed. [ABSTRACT FROM AUTHOR]

As well known, in the analysis of bird impact events the bird is often reduced, even experimentally, to a surrogate projectile modeled as a weakly compressible fluid (typically a mixture of water and air) [15] . From a numerical standpoint, the presence of a free surface and the strong interaction with the aircraft structures represent a limit for traditional computational fluid dynamics methods based on an Eulerian grid. On the other hand, classical Lagrangian methods cannot cope with the extremely large deformations experienced by the projectile during the impact. The Particle Finite Element Method (PFEM) [6,11] is a Lagrangian particle method that can account for very large deformations, preserving the robustness and generality of the finite element method, and thus owning a key advantage over other approaches, e.g. Smoothed Particle Hydrodynamics (SPH) [9] , usually cursed with consistency and stability issues [1,10] . To assess the possibilities of the method in the context of bird impact, theoretical analyses are initially performed based on the impact of a water jet on a rigid surface. Then, the influence of the geometry of a more realistic projectile is analyzed and the capability of the method to take into account separation and fragmentation is highlighted. [ABSTRACT FROM AUTHOR]

Résumé: La maladie périodique (fièvre familiale méditerranéenne) est une maladie héréditaire, à transmission autosomique récessive, faisant partie des maladies auto-inflammatoires. Elle est caractérisée par des épisodes récidivants, de courte durée (en moyenne 24 à 72heures) et de résolution spontanée, comportant de la fièvre et l’inflammation d’une séreuse. La maladie périodique est la plus fréquente des fièvres périodiques au sein des maladies auto-inflammatoires qui constituent un groupe hétérogène et récemment identifié, de maladies caractérisées par des accès fébriles récidivants, sans auto-anticorps, ni lymphocytes T spécifiques de l’antigène. Habituellement, les crises sont déclenchées par des stimuli anodins et peuvent être précédées d’une phase prodromique. Le gène responsable de la fièvre familiale méditerranéenne, appelée MEFV, est situé sur le chromosome 16 (16p13) et code pour la protéine pyrine-marénostrine. Le mécanisme physiopathologique précis de la maladie périodique nécessite d’être encore déterminé. Le nouveau complexe macromoléculaire appelé inflammasome, qui semble jouer un rôle très important dans le contrôle de l’inflammation, pourrait être impliqué dans la pathogénie de la maladie périodique. La complication la plus sévère à long terme est l’amylose AA qui atteint surtout les reins et peut entraîner une insuffisance rénale chronique. Des facteurs de risque, à la fois génétiques et non génétiques, du développement de l’amylose secondaire ont été identifiés. Actuellement, le seul traitement efficace de la maladie périodique est la colchicine. De nouvelles molécules ont été essayées chez des patients réfractaires à la colchicine, mais des études supplémentaires portant sur des effectifs suffisants sont nécessaires avant d’aboutir à des conclusions formelles. [Copyright &y& Elsevier]

Abstract: Familial Mediterranean Fever (FMF) is a hereditary autosomal recessive, autoinflammatory disorder characterized by recurrent, self-limiting episodes of short duration (mean 24–72h) of fever and serositis. FMF is the most frequent periodic febrile syndrome among the autoinflammatory syndromes (AS), a heterogeneous group of recently identified diseases clinically characterized by recurrent febrile attacks, in the absence of autoantibodies and antigen-specific T lymphocytes. In FMF, periodic attacks show inter- and intra-individual variability in terms of frequency and severity. Usually, they are triggered by apparently innocuous stimuli and may be preceded by a prodromal period. The Mediterranean FeVer gene (MEFV) responsible gene maps on chromosome 16 (16p13) encoding the pyrin–marenostrin protein. The precise pathologic mechanism is still to be definitively elucidated; however a new macromolecular complex, called inflammasome, seems to play a major role in the control of inflammation and it might be involved in the pathogenesis of FMF. The most severe long-term complication is type AA amyloidosis, principally affecting the kidney and the cause of chronic renal failure. Two types of risk factors, genetic and non-genetic, have been identified for this complication. Currently, the only effective treatment of Familial Mediterranean Fever is the colchicine. New drugs in a few colchicine resistant patients have been tried, but additional studies on larger series are necessary to draw definitive conclusions. [Copyright &y& Elsevier]

The official method (i.e., isoelectric focusing, IEF) for the detection of bovine milk in cheeses obtained from ovine, caprine or buffalo milk, according to the Commission Implementing Regulation (EU) No 150/2018, was compared with three techniques: lateral flow immunoassay (LFA), ELISA and real-time PCR (RT-PCR). Samples of milk, cheese and vegetable drinks were analysed as control samples and after artificial contamination with bovine milk at different concentrations. All these assays, except for ELISA, showed a good diagnostic performance able to detect milk adulteration at concentrations lower than 1% of bovine milk in caprine, ovine and buffalo milk. Relative sensitivity, specificity and accuracy of both ELISA and RT-PCR compared with IEF were 100%, whereas for LFA they corresponded to 100%, 62.5% and 72.7%, respectively. A good agreement among ELISA and RT-PCR versus IEF was observed but only a moderate agreement between LFA and IEF. [ABSTRACT FROM AUTHOR]