Adaptive modelling of coupled hydrological processes with application in water management

This paper presents recent results of a network project aiming at the modelling and simulation of coupled surface and subsurface flows. In particular, a discontinuous Galerkin method for the shallow water equations has been developed which includes a special treatment of wetting and drying. A robust solver for saturated-unsaturated groundwater flow in homogeneous soil is at hand, which, by domain decomposition techniques, can be reused as a subdomain solver for flow in heterogeneous soil. Coupling of surface and subsurface processes is implemented based on a heterogeneous nonlinear Dirichlet-Neumann method, using the dune-grid-glue module in the numerics software Dune

Myelination- and immune-mediated MR-based brain network correlates

Background Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS), characterized by inflammatory and neurodegenerative processes. Despite demyelination being a hallmark of the disease, how it relates to neurodegeneration has still not been completely unraveled, and research is still ongoing into how these processes can be tracked non-invasively. Magnetic resonance imaging (MRI) derived brain network characteristics, which closely mirror disease processes and relate to functional impairment, recently became important variables for characterizing immune-mediated neurodegeneration; however, their histopathological basis remains unclear. Methods In order to determine the MRI-derived correlates of myelin dynamics and to test if brain network characteristics derived from diffusion tensor imaging reflect microstructural tissue reorganization, we took advantage of the cuprizone model of general demyelination in mice and performed longitudinal histological and imaging analyses with behavioral tests. By introducing cuprizone into the diet, we induced targeted and consistent demyelination of oligodendrocytes, over a period of 5 weeks. Subsequent myelin synthesis was enabled by reintroduction of normal food. Results Using specific immune-histological markers, we demonstrated that 2 weeks of cuprizone diet induced a 52% reduction of myelin content in the corpus callosum (CC) and a 35% reduction in the neocortex. An extended cuprizone diet increased myelin loss in the CC, while remyelination commenced in the neocortex. These histologically determined dynamics were reflected by MRI measurements from diffusion tensor imaging. Demyelination was associated with decreased fractional anisotropy (FA) values and increased modularity and clustering at the network level. MRI-derived modularization of the brain network and FA reduction in key anatomical regions, including the hippocampus, thalamus, and analyzed cortical areas, were closely related to impaired memory function and anxiety-like behavior. Conclusion Network-specific remyelination, shown by histology and MRI metrics, determined amelioration of functional performance and neuropsychiatric symptoms. Taken together, we illustrate the histological basis for the MRI-driven network responses to demyelination, where increased modularity leads to evolving damage and abnormal behavior in MS. Quantitative information about in vivo myelination processes is mirrored by diffusion-based imaging of microstructural integrity and network characteristics

Dead-box proteins: a family affair—active and passive players in RNP-remodeling

DEAD-box proteins are characterized by nine conserved motifs. According to these criteria, several hundreds of these proteins can be identified in databases. Many different DEAD-box proteins can be found in eukaryotes, whereas prokaryotes have small numbers of different DEAD-box proteins. DEAD-box proteins play important roles in RNA metabolism, and they are very specific and cannot mutually be replaced. In vitro, many DEAD-box proteins have been shown to have RNA-dependent ATPase and ATP-dependent RNA helicase activities. From the genetic and biochemical data obtained mainly in yeast, it has become clear that these proteins play important roles in remodeling RNP complexes in a temporally controlled fashion. Here, I shall give a general overview of the DEAD-box protein family

De la valeur sociale des personnes à celle des objets (étude expérimentale de la généralisation de l'utilité et de la désirabilité sociales)

S'inscrivant dans la conception évaluative du jugement social (Beauvois et Dubois, 2009), cette thèse a pour objectif de montrer que les deux dimensions du jugement personnologique (utilité et désirabilité sociales) correspondent à deux modes de connaissance évaluative très généraux intervenant dans le jugement de tout objetsocial. De façon plus précise, on se propose de montrer que ces deux modes de connaissance peuvent 1. être induits à partir de pratiques évaluatives faites tantôt sur des personnes, tantôt sur des objets, et 2. être ensuite généralisés à la description d'objets (après induction sur des personnes) ou de personnes (après induction sur des objets).Deux recherches montrent que les adjectifs évaluatifs courants et propres à la description des objets de consommation sont, comme attendu, massivement structurés par deux dimensions analogues à la désirabilité et à l'utilité sociales (respectivement l'agréabilité et la valeur marchande des objets). Six autres expérimentations, destinées à tester la généralisation des deux modes de connaissance évaluative montrent globalement, commeattendu, qu'il est possible d'induire un mode de connaissance évaluative, surtout celui en lien avec l'utilité sociale, et un mode de connaissance descriptive et que le mode de connaissance induit peut effectivement être généralisé à la connaissance d'un autre registre d'objets (du registre des personnes à celui des objets vs du registre des objets à celui des personnes).Nos résultats suggèrent donc que la désirabilité sociale et l'utilité sociale semblent bien fonctionner comme deux modes de connaissance évaluative généraux tant des personnes que des objets de consommation. Ils confirment aussi que la mobilisation de ces deux dimensions relève bien des pratiques sociales d'évaluation et non de la réalité psychologique des personnes. Les apports théoriques à la conception évaluative, les perspectives de recherches, ainsi qu'une application potentielle à la psychologie du consommateur, sont discutées.Following evaluative framework of social judgment (Beauvois and Dubois, 2009), this thesis aims at showing that the two dimensions of persons judgment (the so called : "social utility" and "social desirability") correspond to two evaluative knowledge's modes that can be applied to common objects judgment. More precisely, we propose to demonstrate that these two evaluative modes can be 1. induced from evaluativepractices made either into the person register, or into the object register, and 2. then generalized to objects descriptions (following induction into person register) or to persons descriptions (following induction into object register).Two researches started with showing that current and evaluative adjectives that are suitable for objects description are massively structured by two dimensions similar to social desirability and social utility (respectively "agreeableness" and "market value"). Six other experiments intended to test the generalization of the two evaluative modes. As predicted, results showed that it is possible to induce the two evaluative knowledgemodes, especially that which pertains to persons social utility and market value, and another descriptive knowledge mode, and that these induced modes can be generalized from persons to objects and conversely from objects to persons.Thus, these findings suggest that the social desirability and the social utility traits dimensions function like two general modes of evaluative knowledge that can be applied to any social object. They also confirm that the mobilization of these two modes is not a consequence of psychological realism, but result of evaluative social practices. Theoretical implications for the evaluative framework as well as directions for future work and apotential application for consumer psychology are discussed.METZ-SCD (574632105) / SudocNANCY1-Bib. numérique (543959902) / SudocNANCY2-Bibliotheque electronique (543959901) / SudocNANCY-INPL-Bib. électronique (545479901) / SudocSudocFranceF

We judge other's personality on the sole basis of their economic contribution to society

International audienc

Cortex Parcellation Associated Whole White Matter Parcellation in Individual Subjects

The investigation of specific white matter areas is a growing field in neurological research and is typically achieved through the use of atlases. However, the definition of anatomically based regions remains challenging for the white matter and thus hinders region-specific analysis in individual subjects. In this article, we focus on creating a whole white matter parcellation method for individual subjects where these areas can be associated to cortex regions. This is done by combining cortex parcellation and fiber tracking data. By tracking fibers out of each cortex region and labeling the fibers according to their origin, we populate a candidate image. We then derive the white matter parcellation by classifying each white matter voxel according to the distribution of labels in the corresponding voxel from the candidate image. The parcellation of the white matter with the presented method is highly reliable and is not as dependent on registration as with white matter atlases. This method allows for the parcellation of the whole white matter into individual cortex region associated areas and, therefore, associates white matter alterations to cortex regions. In addition, we compare the results from the presented method to existing atlases. The areas generated by the presented method are not as sharply defined as the areas in most existing atlases; however, they are computed directly in the DWI space of the subject and, therefore, do not suffer from distortion caused by registration. The presented approach might be a promising tool for clinical and basic research to investigate modalities or system specific micro structural alterations of white matter areas in a quantitative manner

Is disability really an obstacle to success? Impact of a disability simulation on motivation and performance

International audienc

Is disability really an obstacle to success? Impact of a disability simulation on motivation and performance

International audienc

Early and Degressive Putamen Atrophy in Multiple Sclerosis

Putamen atrophy and its long-term progress during disease course were recently shown in patients with multiple sclerosis (MS). Here we investigated retrospectively the time point of atrophy onset in patients with relapsing-remitting MS (RRMS). 68 patients with RRMS and 26 healthy controls (HC) were admitted to 3T MRI in a cross-sectional study. We quantitatively analyzed the putamen volume of individual patients in relation to disease duration by correcting for age and intracranial volume (ICV). Patient’s relative putamen volume (RPV), expressed in percent of ICV, was significantly reduced compared to HC. Based on the correlation between RPV and age, we computed the age-corrected RPV deviation (ΔRPV) from HC. Patients showed significantly negative ΔRPV. Interestingly, the age-corrected ΔRPV depended logarithmically on disease duration: Directly after first symptom manifestation, patients already showed a reduced RPV followed by a further degressive volumetric decline. This means that atrophy progression was stronger in the first than in later years of disease. Putamen atrophy starts directly after initial symptom manifestation or even years before, and progresses in a degressive manner. Due to its important role in neurological functions, early detection of putamen atrophy seems necessary. High-resolution structural MRI allows monitoring of disease course