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We study the inverse source (primary current) localisation problem using the electrical potential measured point-wise inside the head with stereo-ElectroEncephaloGraphy (sEEG), the electrical potential measured point-wise on the scalp with ElectroEncephaloGraphy (EEG) or the magnetic flux density measured point-wise outside the head with MagnetoEncephaloGraphy (MEG). We present a method that works on a wide range of models of primary currents, in particular we give details for primary currents that are assumed to be smooth vector-fields that are supported on and normally oriented to the grey/white matter interface. Irrespective of the data used we need to understand the transmission of the electric potential associated with a recovered source through the head hence we solve the cortical mapping problem. To ensure that the electric potential and normal currents are continuous in the head, the electric potential is expressed as a linear combination of double layer potentials and the magnetic flux density is expressed as a linear combination of single layer potentials. Numerically, we solve the problems on meshed surfaces of the grey/white matter interface, cortical surface, skull and scalp. A main feature of the numerical approach we take is that on the meshed surfaces we can compute the double and single layer potentials exactly and at arbitrary points. Because we study the transmission of the electric potential in head irrespective of the modality used, this enables the coupling of electric and magnetic data in the source recovery problem. We provide numerical examples of the source recovery and inverse cortical mapping using synthetic data.

Resume Introduction Le positionnement des implants d’une prothese totale de hanche (PTH) est essentiel pour limiter les complications et optimiser les resultats fonctionnels. Dans une etude recente sur plus de 100 PTH posees par voie anterieure sur table orthopedique, nous avions constate que l’anteversion moyenne de la cupule etait plus importante (30°) que celle recommandee (20°). Pour expliquer ce phenomene, nous avons evoque que le plan pelvien anterieur (PPA), defini par le plan passant par les epines iliaques anterosuperieures et la symphyse pubienne, qui sert de repere a la pose et au calcul de l’anteversion de la cupule n’etait pas horizontal une fois le patient allonge sur la table orthopedique. Cette notion n’a pas ete evaluee ; aussi, nous avons mene une etude prospective afin de : 1) mesurer la position du bassin sur table orthopedique ; 2) comparer a la position debout ; 3) evaluer son retentissement sur l’anteversion de la cupule. Hypothese La version du bassin debout etait identique a la version du bassin couche sur table orthopedique. Materiel et methodes Une etude monocentrique prospective sur 3 mois a ete menee. Tous les patients operes pour une PTH sur table orthopedique par voie anterieure directe ont ete inclus. La position du bassin a ete evaluee par la mesure de l’inclinaison du PPA sur des radiographies de bassin de profil installe sur table orthopedique et debout. Pour le retentissement de la position du bassin sur le positionnement de la cupule, la mesure de l’anteversion etait faite grâce au systeme d’imagerie EOS. L’anteversion anatomique de la cupule etait celle mesuree par rapport au PPA. Resultats Cinquante-huit patients ont ete inclus (32 femmes, 26 hommes) avec un âge moyen de 67 ans. L’inclinaison du PPA couche etait 6° ± 8,3 [extremes de −10,5 a 31,0] (indiquant un bassin retroverse sur la table orthopedique). La difference entre l’inclinaison du PPA debout et couche (a 90° pres) etait non significative (debout en moyenne 4,5° [extremes de −11,0 a 27,0] contre couche sur table en moyenne de 6° [extremes de −10,5 a 31,0] (p = 0,75). Une forte correlation entre inclinaison du PPA couche et anteversion anatomique de la cupule etait observee (p Conclusion Le bassin couche sur table orthopedique n’est pas systematiquement horizontal et sa position sur la table orthopedique est similaire a sa position debout, a 90 degres pres. L’analyse du positionnement du bassin preoperatoire nous semble indispensable en programmation d’une PTH. Niveau de preuve IV ; etude prospective de cohorte.

À la fin des années 70, l’aéronautique prend conscience de la responsabilité du facteur humain dans les accidents. Naîtront, alors, les premières formations CRM (Crew Resource Management). Ce n’est que plus tardivement que le domaine du soin s’intéressera à son tour au facteur humain. Au travers de ses différents outils, allant de la check-list à la simulation, en passant par l’analyse des évènements indésirables, le monde médical progresse dans la prise en considération de la composante humaine.En France, le projet PACTE propose depuis 2014 des méthodes et des outils pour améliorer le travail en équipe afin de sécuriser la prise en charge du patient, s’inscrivant dans une démarche de CRM santé.Notre étude porte sur la modification des comportements humains chez le personnel formé. Les résultats révèlent un réel intérêt des équipes pour le CRM et montrent que la majorité d’entre eux mettent en place certains outils acquis lors de la formation. Elle montre également que la mise en place des outils se heurte parfois au manque de formation des collaborateurs. Fort des résultats de cette étude, le SAMU 83 a pris la décision en septembre 2022 de s’inscrire au projet PACTE.Ainsi, on peut espérer que bientôt le facteur humain et le CRM prendront en médecine autant d’importance que dans le domaine de l’aviation.

Objective Soluble fibrin (SF) is a substantial component of plasma fibrinogen (fg), but its composition, functions, and clinical relevance remain unclear. The study aimed to evaluate the molecular composition and procoagulant function(s) of SF. Materials and Methods Cryoprecipitable, SF-rich (FR) and cryosoluble, SF-depleted (FD) fg isolates were prepared and adsorbed on one hydrophilic and two hydrophobic surfaces and scanned by atomic force microscopy (AFM). Standard procedures were used for fibrin polymerization, crosslinking by factor XIII, electrophoresis, and platelet adhesion. Results Relative to FD fg, thrombin-induced polymerization of FR fg was accelerated and that induced by reptilase was markedly delayed, attributable to its decreased (fibrinopeptide A) FpA. FR fg adsorption to each surface yielded polymeric clusters and co-cryoprecipitable solitary monomers. Cluster components were crosslinked by factor XIII and comprised ≤21% of FR fg. In contrast to FD fg, FR fg adsorption on hydrophobic surfaces resulted in fiber generation enabled by both clusters and solitary monomers. This began with numerous short protofibrils, which following prolonged adsorption increased in number and length and culminated in surface-linked three-dimensional fiber networks that bound platelets. Conclusion The abundance of adsorbed protofibrils resulted from (1) protofibril/fg clusters whose fg was dissociated during adsorption, and (2) adsorbed des-AA monomers that attracted solution counterparts initiating protofibril assembly and elongation by their continued incorporation. The substantial presence of both components in transfused plasma and cryoprecipitate augments hemostasis by accelerating thrombin-induced fibrin polymerization and by tightly anchoring the resulting clot to the underlying wound or to other abnormal vascular surfaces.

Based on a socio-psychological approach, this study aims to analyze the socio-cognitive processes involved in the formation of cognitions and emotions associated with gene editing of the human embryo. More specifically, we want to study the contribution of gender – as a socio-symbolic and hierarchical order – by investigating the social value that individuals attribute to the genetic materials of men versus women.

In this work, we consider the inverse source recovery problem from sEEG, EEG and MEG point-wise data. We regard this as an inverse source recovery problem for L2 vector-fields normally oriented and supported on the grey/white matter interface, which together with the brain, skull and scalp form a non-homogeneous layered conductor. We assume that the quasistatic approximation of Maxwell’s equation holds for the electro-magnetic fields considered. The electric data is measured point-wise inside and outside the conductor while the magnetic data is measured only point-wise outside the conductor. These ill-posed problems are solved via Tikhonov regularization on triangulations of the interfaces and a piecewise linear model for the current on the triangles. Both in the continuous and discrete formulation the electric potential is expressed as a linear combination of double layer potentials while the magnetic flux density in the continuous case is a vector-surface integral whose discrete formulation features single layer potentials. A main feature of our approach is that these contributions can be computed exactly. Due to the consideration of the regularity conditions of the electric potential in the inverse source recovery problem, the Cauchy transmission problem for the electric potential is inadvertently solved as well. In the problem, we propagate only the electric potential while the normal derivatives at the interfaces of discontinuity of the electric conductivities are computed directly from the resulting solution. This reduces the computational complexity of the problem. There is a direct connection between the magnetic flux density and the electrical potential in conductors such as the one we explore, hence a coupling of the sEEG, EEG and MEG data for solving the respective inverse source recovery problems simultaneously is direct. We treat these problems in a unified approach that uses only single and/or double layer potentials. We provide numerical examples using realistic meshes of the head with synthetic data.

International audience; Reducing carbon emissions and electricity costs in industry is a major challenge to ensure competitiveness and compliance with new climate policies. Photovoltaic power offers a promising solution but also brings considerable uncertainties and risks that may endanger the continuity and quality of supply. From an operational point of view, large-scale integration of solar power could result in unmet demand, electrical instabilities and equipment damage. The performance and lifetime of conventional fossil equipment are likely to be altered by repeated transient operations, making it necessary to adopt specific modeling tools. Control strategies and sizing methodologies must be adapted to account for the strong reliability constraint while dealing with significant production uncertainties. In addition, conventional mitigation technologies, such as storage and load flexibility, have limited potential in these applications and may result in high investments or penalties if they are not properly assessed. This study provides an overview of these challenges by providing a transversal analysis of the scientific literature from fossil engine thermodynamics to control system theory applied to industrial systems. The main characteristics of reliability-constrained microgrids are identified and a conceptual definition is proposed by analyzing state-of-the art studies of various industrial applications and taking oil-and gas microgrids as an enlightening example. Then follows a review of the challenges of accounting for dynamical behavior of fossil equipment, PV and storage systems, ending with the identification of several research gaps. Finally, applicable control strategies and sizing techniques are presented.

Soumis pour publication.; International audience; We propose a numerical method for solving a family of source estimation inverse problems from Cauchy data for Poisson (conductivity) PDE in non-homogeneous domains. The targeted application is the electroencephalography (EEG) dipolar source localization problem in brain imaging, for which it allows to take into account the specific heterogeneity of the skull in the data transmission step (cortical mapping) from the scalp to the cortex.

La question de l’urgence climatique qui fait débat depuis plusieurs années semble aujourd’hui converger vers une certaine forme de consensus auprès des scientifiques. Les études et recommandations qui s’en suivent sont dorénavant sans ambiguïté : si nos modes de production, de consommation n’évoluent pas, la catastrophe écologique semble assurée. Dans ce contexte, quelle est alors la responsabilité des institutions en charge de former les managers et travailleurs de demain ? Comment repenser les programmes de formation face à l’accélération du dérèglement climatique et de la détérioration des ressources naturelles ? C’est justement la question de l’enseignement de la comptabilité qui se voit être discutée au sein de ce chapitre. Discipline au cœur des activités productives des organisations, la comptabilité, dans sa forme actuelle, ignore les répercussions écologiques des activités organisationnelles. À travers cette réflexion, nous mobilisons l’approche critique de la comptabilité pour envisager l’émergence de nouveaux modèles comptables plus enclins à l’intégration des conséquences écologiques et climatiques dans les comptes. Cette opportunité de repenser l’enseignement de la comptabilité en s’émancipant des modèles traditionnels dominants nous permet de discuter et mettre à l’épreuve le contenu, les modalités d’apprentissage de la comptabilité et de proposer quelques pistes d’évolution envisageables.