Création artistique et relation esthétique : objets, cadres catégoriels et fonctions

Jean-Marie Schaeffer, directeur d’étudesYolaine Escande, Nathalie Heinich, directrices de recherche au CNRSDenis Vidal, directeur de recherche à l’IRD La formation des préférences esthétiques et artistiques. II Durant cette année conclusive du séminaire consacré à l’étude de la relation esthétique, nous avons analysé la composante « publique » de l’appréciation esthétique, ce qu’on appelle traditionnellement le « jugement de goût ». Dans notre étude nous avons pris cette expression en son ext..

Création artistique et relation esthétique : objets, cadres catégoriels et fonctions

Jean-Marie Schaeffer, directeur d’étudesGabriel Ruget, professeur à l’ENS-CachanYolaine Escande, directrice de recherche au CNRSDenis Vidal, directeur de recherche à l’IRD Le fait esthétique III : l’esthétique littéraire Dans la continuité des années précédentes, le séminaire a exploré le pôle esthétique de la problématique des arts. Après avoir abordé les modalités de la relation esthétique dans le champ de la vision, des images et des sons (2005-2007), on s’est penché sur les caractéristiqu..

Création artistique et relation esthétique : objets, cadres catégoriels et fonctions

Jean-Marie Schaeffer, directeur d’étudesGabriel Ruget, professeur à l’ENS-CachanYolaine Escande, directrice de recherche au CNRSDenis Vidal, directeur de recherche à l’IRD Le fait esthétique III : l’esthétique littéraire Dans la continuité des années précédentes, le séminaire a exploré le pôle esthétique de la problématique des arts. Après avoir abordé les modalités de la relation esthétique dans le champ de la vision, des images et des sons (2005-2007), on s’est penché sur les caractéristiqu..

How Designers conceive utility, usefulness and needs construction in design: an exploratory study with three contrasted designers’ profiles

Usefulness is considered as a major criterion in ergonomics design. Our objective is to show that heterogeneity and diversity of designers’ profiles could lead to a partially shared representation of the utility and usefulness, methods and tools. To do this, we explore the representations of engineers, graphic designers and ergonomists on the utility, usefulness and needs construction in the design. The methodology developed for studying these representations is a categorical analysis of verbalisations produced during semi-structured interviews. We provide elements of understanding on the relationship between the designer’s profiles and the representations on the definitions of utility and usefulness, and on the needs construction process (design phases, methods, tools and stakeholders involved)

Binding of Estrogenic Compounds to Recombinant Estrogen Receptor-α: Application to Environmental Analysis

Estrogenic activity in environmental samples could be mediated through a wide variety of compounds and by various mechanisms. High-affinity compounds for estrogen receptors (ERs), such as natural or synthetic estrogens, as well as low-affinity compounds such as alkylphenols, phthalates, and polychlorinated biphenyls are present in water and sediment samples. Furthermore, compounds such as polycyclic aromatic hydrocarbons, which do not bind ERs, modulate estrogen activity by means of the aryl hydrocarbon receptor (AhR). In order to characterize compounds that mediate estrogenic activity in river water and sediment samples, we developed a tool based on the ER-αligand-binding domain, which permitted us to estimate contaminating estrogenic compound affinities. We designed a simple transactivation assay in which compounds of high affinity were captured by limited amounts of recombinant ER-αand whose capture led to a selective inhibition of transactivation. This approach allowed us to bring to light that water samples contain estrogenic compounds that display a high affinity for ERs but are present at low concentrations. In sediment samples, on the contrary, we showed that estrogenic compounds possess a low affinity and are present at high concentration. Finally, we used immobilized recombinant ER-αto separate ligands for ER and AhR that are present in river sediments. Immobilized ER-α, which does not retain dioxin-like compounds, enabled us to isolate and concentrate ER ligands to facilitate their further analysis

Phase transition in the collisionless regime for wave-particle interaction

Gibbs statistical mechanics is derived for the Hamiltonian system coupling self-consistently a wave to N particles. This identifies Landau damping with a regime where a second order phase transition occurs. For nonequilibrium initial data with warm particles, a critical initial wave intensity is found: above it, thermodynamics predicts a finite wave amplitude in the limit of infinite N; below it, the equilibrium amplitude vanishes. Simulations support these predictions providing new insight on the long-time nonlinear fate of the wave due to Landau damping in plasmas.Comment: 12 pages (RevTeX), 2 figures (PostScript

Spatial analysis of the glioblastoma proteome reveals specific molecular signatures and markers of survival

Molecular heterogeneity is a key feature of glioblastoma that impedes patient stratification and leads to large discrepancies in mean patient survival. Here, we analyze a cohort of 96 glioblastoma patients with survival ranging from a few months to over 4 years. 46 tumors are analyzed by mass spectrometry-based spatially-resolved proteomics guided by mass spectrometry imaging. Integration of protein expression and clinical information highlights three molecular groups associated with immune, neurogenesis, and tumorigenesis signatures with high intra-tumoral heterogeneity. Furthermore, a set of proteins originating from reference and alternative ORFs is found to be statistically significant based on patient survival times. Among these proteins, a 5-protein signature is associated with survival. The expression of these 5 proteins is validated by immunofluorescence on an additional cohort of 50 patients. Overall, our work characterizes distinct molecular regions within glioblastoma tissues based on protein expression, which may help guide glioblastoma prognosis and improve current glioblastoma classification

Urochordate Histoincompatible Interactions Activate Vertebrate-Like Coagulation System Components

The colonial ascidian Botryllus schlosseri expresses a unique allorecognition system. When two histoincompatible Botryllus colonies come into direct contact, they develop an inflammatory-like rejection response. A surprising high number of vertebrates' coagulation genes and coagulation-related domains were disclosed in a cDNA library of differentially expressed sequence tags (ESTs), prepared for this allorejection process. Serine proteases, especially from the trypsin family, were highly represented among Botryllus library ortholgues and its “molecular function” gene ontology analysis. These, together with the built-up clot-like lesions in the interaction area, led us to further test whether a vertebrate-like clotting system participates in Botryllus innate immunity. Three morphologically distinct clot types (points of rejection; POR) were followed. We demonstrated the specific expression of nine coagulation orthologue transcripts in Botryllus rejection processes and effects of the anti-coagulant heparin on POR formation and heartbeats. In situ hybridization of fibrinogen and von Willebrand factor orthologues elucidated enhanced expression patterns specific to histoincompatible reactions as well as common expressions not augmented by innate immunity. Immunohistochemistry for fibrinogen revealed, in naïve and immune challenged colonies alike, specific antibody binding to a small population of Botryllus compartment cells. Altogether, molecular, physiological and morphological outcomes suggest the involvement of vertebrates-like coagulation elements in urochordate immunity, not assigned with vasculature injury

Life-Cycle and Genome of OtV5, a Large DNA Virus of the Pelagic Marine Unicellular Green Alga Ostreococcus tauri

Large DNA viruses are ubiquitous, infecting diverse organisms ranging from algae to man, and have probably evolved from an ancient common ancestor. In aquatic environments, such algal viruses control blooms and shape the evolution of biodiversity in phytoplankton, but little is known about their biological functions. We show that Ostreococcus tauri, the smallest known marine photosynthetic eukaryote, whose genome is completely characterized, is a host for large DNA viruses, and present an analysis of the life-cycle and 186,234 bp long linear genome of OtV5. OtV5 is a lytic phycodnavirus which unexpectedly does not degrade its host chromosomes before the host cell bursts. Analysis of its complete genome sequence confirmed that it lacks expected site-specific endonucleases, and revealed the presence of 16 genes whose predicted functions are novel to this group of viruses. OtV5 carries at least one predicted gene whose protein closely resembles its host counterpart and several other host-like sequences, suggesting that horizontal gene transfers between host and viral genomes may occur frequently on an evolutionary scale. Fifty seven percent of the 268 predicted proteins present no similarities with any known protein in Genbank, underlining the wealth of undiscovered biological diversity present in oceanic viruses, which are estimated to harbour 200Mt of carbon