Collège de France

About: Collège de France is a education organization based out in Paris, France. It is known for research contribution in the topics: Population & Receptor. The organization has 6541 authors who have published 11983 publications receiving 648742 citations. The organization is also known as: College de France.

Structure and kinematics of the Indo-Burmese Wedge: Recent and fast growth of the outer wedge

Abstract: [1] The northern Sunda subduction zone, offshore Burma, and the associated Indo-Burmese Wedge mark the active eastern boundary of the Burma Platelet jammed between the India Plate and the Sunda Plate. The aim of this paper is to provide a structural and kinematics analysis of the Indo-Burmese Wedge based on seismic reflection, geodetic, and geological field data. We found out that the Indo-Burmese Wedge is the place of diffuse strain partitioning: right-lateral shearing in the innermost part and E-W shortening in the outermost part. In the outer wedge, thick-skinned deformation overprints thin-skinned deformation. It can be explained by the required preservation of the critical taper after the fast westward propagation of the outer wedge above a very efficient clayey decollement layer. The thick-skinned deformation is here characterized by major right-lateral strike-slip faults (the Kaladan Fault and the Chittagong Coastal Fault) and yet a typical internal deformation of the Indo-Burmese Wedge. We suggest that the westward migration of internal right-lateral shear deformation allows preservation of the strain-partitioning ratios between internal N-S trending right-lateral shearing and external E-W shortening. Some seismic lines show that the outer wedge deformation is not older than 2 Ma. Its propagation could have been enhanced by the large amount of sediments filling up the Sylhet flexural basin formed after the Pliocene tectonic uplift of the Shillong Plateau.

A Crypt-Specific Core Microbiota Resides in the Mouse Colon

Abstract: In an attempt to explore the microbial content of functionally critical niches of the mouse gastrointestinal tract, we targeted molecular microbial diagnostics of the crypts that contain the intestinal stem cells, which account for epithelial regener- ation. As current evidence indicates, the gut microbiota affects epithelial regeneration; bacteria that are likely to primarily par- ticipate in this essential step of the gut, microbiota cross talk, have been identified. We show in this article that only the cecal and colonic crypts harbor resident microbiota in the mouse and that regardless of the line and breeding origin of these mice, this bacterial population is unexpectedly dominated by aerobic genera. Interestingly, this microbiota resembles the restricted micro- biota found in the midgut of invertebrates; thus, the presence of our so-called "crypt-specific core microbiota" (CSCM) in the mouse colon potentially reflects a coevolutionary process under selective conditions that can now be addressed. We suggest that CSCM could play both a protective and a homeostatic role within the colon. This article is setting the bases for such studies, par- ticularly by providing a bona fide—and essentially cultivable—crypt microbiota of reference. IMPORTANCE Metagenomic typing of the whole-gut luminal microbiome was recently provided, revealing great opportunities for physiological and physiopathological analysis of the host-microbiota interface. On this basis, it appears increasingly important to analyze which niches of the gut exposed to a particular microbiota are of major functional importance, specifically focusing on the crypt, which accounts for permanent epithelial renewal, and to analyze how this microbiota compares to its luminal counterpart in composition and quantity. Crypt-specific core microbiotas may show themselves as important elements regard- ing crypt protection and homeostasis of its functions.

Supramolecular chemistry — Molecular information and the design of supramolecular materials

Abstract: Molecular information expressed through molecular recognition events provides means for directing the spontaneous formation of supramolecular species from complementary components. It may allow the design and engineering of supramolecular materials, in particular of liquid crystalline and of polymeric nature. Thus, supramolecular mesophases have been obtained from molecular recognition-induced association of suitable subunits. The self-assembly of complementary ditopic components generates liquid crystalline “polymers” of supramolecular nature; it takes place by a progressive growth revealed by electron microscopy: from nuclei, to filaments, to tree-like species, to strings and fibers that present helicity induced by the chirality of the subunits. A rich variety of structures and properties may be expected to result from the blending of supramolecular chemistry with polymer chemistry and materials science.