Demain ne meurt jamais

Cette recherche porte sur un corpus historique composé du dernier numéro édité par 52 hebdomadaires d’information générale belges francophones « décédés » après-guerre (1950-2000). Elle permet de mieux cerner la représentation que se font les journaux et les journalistes de leur identité et de leur rôle social. Ceci, à un moment particulièrement douloureux : celui où ils brisent leur plume. De même qu’un mourant chuchote ses dernières vérités à l’oreille de celui qui le veille, se pencher sur les récits de (fin) de vie présents dans des dizaines de derniers numéros en révèle un peu plus sur la crise de l’information écrite généraliste.This research focuses on a historic corpus consisting of the terminal issues of 52 Belgian weekly information magazines (in French) which have disappeared in the post-WWII period (1950-2000).The research helps to better appraise the way newspapers and journalists view themselves and their social role, especially in a painful moment, i.e., when they have to leave the place. Just as a dying man whispers his last words to the ear of his wife, analysing the « stories of the last day » told in terminal issues of magazines contributes to know a little bit more about the crisis of the general information press

Jean-Marie Charon, La presse quotidienne

Moins de dix ans après la première édition de La presse quotidienne, Jean-Marie Charon propose une « nouvelle édition entièrement refondue et mise à jour » de l’ouvrage désormais rangé dans la section « Culture-communication » de la collection Repères. À comparer les deux versions, l’on constate que le renouvellement annoncé dès la couverture ne relève pas de la simple formule d’appel. Les données ont effectivement été largement actualisées. Certes, on ne s’attend pas à moins, au nom de la qu..

Marie-Anne Couderc, La Semaine de Suzette. Histoires de filles

« Nous demeurons, nous, les sexagénaires – et plus âgées encore – reconnaissantes à cette Semaine de Suzette qui nous a aidées, secourues dans nos détresses, amusées, entraînées avec elle bien loin d’un quotidien parfois difficile, et a, en somme, officiellement reconnu notre existence » (p. 242). Il est rare qu’à la façon de Marie-Anne Couderc, l’analyste mette en scène la relation passionnée qu’elle a entretenue avec l’objet qu’elle étudie. Il est tout aussi surprenant qu’une auteure convoq..

Shape Transition in the Epitaxial Growth of Gold Silicide in Au Thin Films on Si(111)

Growth of epitaxial gold silicide islands on bromine-passivated Si(111) substrates has been studied by optical and electron microscopy, electron probe micro analysis and helium ion backscattering. The islands grow in the shape of equilateral triangles up to a critical size beyond which the symmetry of the structure is broken, resulting in a shape transition from triangle to trapezoid. The island edges are aligned along $Si[110]$ directions. We have observed elongated islands with aspect ratios as large as 8:1. These islands, instead of growing along three equivalent [110] directions on the Si(111) substrate, grow only along one preferential direction. This has been attributed to the vicinality of the substrate surface.Comment: revtex version 3.0, 11 pages 4 figures available on request from [email protected] - IP/BBSR/93-6

LEEM investigation of the faceting of the Pt covered W(111) surface

A low energy electron microscope (LEEM) has been used to investigate the faceting of W(111) as induced by Pt. The atomically rough W(111) surface, when fully covered with a monolayer film of Pt and annealed to temperatures higher than {approximately} 750 K, experiences a significant morphological restructuring: the initially planar surface undergoes a faceting transition and forms three-sided pyramids with {211} faces. The experiments demonstrate the capability of LEEM for imaging both the fully and partially faceted surface. In addition, we have observed the formation of the facets in real time, when Pt is dosed onto the heated surface. We find that the transition from planar surface, to partially faceted surface, and to fully faceted surface proceeds through the nucleation and growth of spatially separated faceted regions

Structure determination of the (1×2) and (1×3) reconstructions of Pt(110) by low-energy electron diffraction

The atomic geometry of the (1×2) and (1×3) structures of the Pt(100) surface has been determined from a low-energy electron-diffraction intensity analysis. Both structures are found to be of the missing-row type, consisting of (111) microfacets, and with similar relaxations in the subsurface layers. In both reconstructions the top-layer spacing is contracted by approximately 20% together with a buckling of about 0.17 Å in the third layer and a small lateral shift of about 0.04 Å in the second layer. Further relaxations down to the fourth layer were detectable. The surface relaxations correspond to a variation of interatomic distances, ranging from -7% to +4%, where in general a contraction of approximately 3% for the distances parallel to the surface occurs. The Pendry and Zanazzi-Jona R factors were used in the analysis, resulting in a minimum value of RP=0.36 and RZJ=0.26 for 12 beams at normal incidence for the (1×2) structure, and similar agreement for 19 beams of the (1×3) structure. The (1×3) structure has been reproducibly obtained after heating the crystal in an oxygen atmosphere of 5×10-6 mbar at 1200 K for about 30 min and could be removed by annealing at 1800 K for 45 min after which the (1×2) structure appeared again. Both reconstructed surfaces are clean within the detection limits of the Auger spectrometer. CO adsorption lifts the reconstruction in both structures. After desorption at 500 K the initial structures appear again, indicating that at least one of the reconstructions does not represent the equilibrium structure of the clean surface and may be stabilized by impurities

Pro-autophagic signal induction by bacterial pore-forming toxins

Pore-forming toxins (PFT) comprise a large, structurally heterogeneous group of bacterial protein toxins. Nucleated target cells mount complex responses which allow them to survive moderate membrane damage by PFT. Autophagy has recently been implicated in responses to various PFT, but how this process is triggered is not known, and the significance of the phenomenon is not understood. Here, we show that S. aureus α-toxin, Vibrio cholerae cytolysin, streptolysin O and E. coli haemolysin activate two pathways leading to autophagy. The first pathway is triggered via AMP-activated protein kinase (AMPK). AMPK is a major energy sensor which induces autophagy by inhibiting the target of rapamycin complex 1 (TORC1) in response to a drop of the cellular ATP/AMP-ratio, as is also observed in response to membrane perforation. The second pathway is activated by the conserved eIF2α-kinase GCN2, which causes global translational arrest and promotes autophagy in response to starvation. The latter could be accounted for by impaired amino acid transport into target cells. Notably, PKR, an eIF2α-kinase which has been implicated in autophagy induction during viral infection, was also activated upon membrane perforation, and evidence was obtained that phosphorylation of eIF2α is required for the accumulation of autophagosomes in α-toxin-treated cells. Treatment with 3-methyl-adenine inhibited autophagy and disrupted the ability of cells to recover from sublethal attack by S. aureus α-toxin. We propose that PFT induce pro-autophagic signals through membrane perforation–dependent nutrient and energy depletion, and that an important function of autophagy in this context is to maintain metabolic homoeostasis