Strain superlattices and macroscale suspension of Graphene induced by corrugated substrates

We investigate the organized formation of strain, ripples and suspended features in macroscopic CVD-prepared graphene sheets transferred onto a corrugated substrate made of an ordered arrays of silica pillars of variable geometries. Depending on the aspect ratio and sharpness of the corrugated array, graphene can conformally coat the surface, partially collapse, or lay, fakir-like, fully suspended between pillars over tens of micrometers. Upon increase of pillar density, ripples in collapsed films display a transition from random oriented pleats emerging from pillars to ripples linking nearest neighboring pillars organized in domains of given orientation. Spatially-resolved Raman spectroscopy, atomic force microscopy and electronic microscopy reveal uniaxial strain domains in the transferred graphene, which are induced and controlled by the geometry. We propose a simple theoretical model to explain the transition between suspended and collapsed graphene. For the arrays with high aspect ratio pillars, graphene membranes stays suspended over macroscopic distances with minimal interaction with pillars tip apex. It offers a platform to tailor stress in graphene layers and open perspectives for electron transport and nanomechanical applications

Basic notions of information structure

This article takes stock of the basic notions of Information Structure (IS). It first provides a general characterization of IS — following Chafe (1976) — within a communicative model of Common Ground(CG), which distinguishes between CG content and CG management. IS is concerned with those features of language that concern the local CG. Second, this paper defines and discusses the notions of Focus (as indicating alternatives) and its various uses, Givenness (as indicating that a denotation is already present in the CG), and Topic (as specifying what a statement is about). It also proposes a new notion, Delimitation, which comprises contrastive topics and frame setters, and indicates that the current conversational move does not entirely satisfy the local communicative needs. It also points out that rhetorical structuring partly belongs to IS.Peer Reviewe

Finances publiques pour les concours

International audienc

Finances publiques pour les concours

International audienc

Finances publiques pour les concours

International audienc

Percepción de funcionalidad familiar y trauma infantojuvenil: un estudio cualitativo

Se comparan las características de quince mujeres hospitalizadas en un hospital general publico en Santiago de Chile, que recuerdan más de tres experiencias traumáticas antes de los 16 años, con 15 casos que no recuerdan ninguno. En los 30 casos se estudian características socio-demográficas, y se aplican las siguientes escalas: Acontecimientos Traumáticos de Perry (TAI), las escalas de percepción familiar de Valdés y Cols (CTF-CSF) y la Escala Abreviada de Conductas de Riesgo (ECRA). Se comparan ambos grupos, constatándose una mayor frecuencia de dificultades en las relaciones interpersonales, disfuncionalidad familiar y conductas de riesgo en las mujeres con antecedentes anamnésticos de polipsicotrauma antes de los 16 años. Se concluye insistiendo en la importancia de la prevención de la violencia intrafamiliar y de los tratamientos adecuados para las víctima