'Marée', 'charcuterie-traiteur'.:Le rayon traditionnel en grande surface, lieu d'expérimentation

Les auteurs s’intéressent aux rayons dits « traditionnels » des grandes surfaces, en tant que dispositifs de médiation. Deux rayons sont choisis en raison de leur double asymétrie : le rayon « marée » qui a l’exclusivité de ses produits, par ailleurs peu transformés, et le rayon « charcuterie-traiteur » dont les produits – transformés et standardisés – sont en concurrence avec ceux conditionnés et accessibles dans des rayons en libre-service. À partir de l’observation des interactions entre vendeurs et clients, complétée par des entretiens dans une dizaine de magasins en France (villes de province et banlieue parisienne), ils établissent l’absence d’analogie entre le rayon « tradition » et le petit commerce de centre-ville. Pour ce faire, les auteurs mettent en lumière des mises en scène et des expérimentations visant à reformuler les qualités des produits comme les compétences des consommateurs. De manière plus générale, ces dispositifs contribuent à révéler et à formater, par ajustements successifs, la demande ; ces processus s’avèrent nécessaires au bon fonctionnement de ce dispositif économique.The authors study "traditional" hypermarket counters as places of mediation. Two of them have been chosen for their double asymmetry: the "fresh fish" counter, which sells the exclusivity of its products that are not highly processed, and the "pork butcher and delicatessen" counter, whose products–processed and standardized–are in competition with the packaged products available in self-service areas. Observation of interactions between salesmen and customers complemented with interviews made in about ten hypermarkets both in provincial towns and in the suburbs of Paris shows that there exists no analogy between the "traditional" counter and the small shop in the town center. The authors point out staging and experiments aiming at reformulating both the products' qualities and the consumers' competences. More generally, these actions contribute to reveal and shape by successive adjustments a demand that is necessary for a good working of this economic strategy

Utilisation de la grille pour la simulation de température de brillance dans une atmosphère nuageuse composée de cirrus

Utilisation de la grille pour la simulation de température de brillance dans une atmosphère nuageuse composée de cirru

What Else is Revealed by Order-Revealing Encryption?

The security of order-revealing encryption (ORE) has been unclear since its invention. Dataset characteristics for which ORE is especially insecure have been identified, such as small message spaces and low-entropy distributions. On the other hand, properties like one-wayness on uniformly-distributed datasets have been proved for ORE constructions. This work shows that more plaintext information can be extracted from ORE ciphertexts than was previously thought. We identify two issues: First, we show that when multiple columns of correlated data are encrypted with ORE, attacks can use the encrypted columns together to reveal more information than prior attacks could extract from the columns individually. Second, we apply known attacks, and develop new attacks, to show that the \emph{leakage} of concrete ORE schemes on non-uniform data leads to more accurate plaintext recovery than is suggested by the security theorems which only dealt with uniform inputs

Identification of Novel Functions for Hepatitis C Virus Envelope Glycoprotein E1 in Virus Entry and Assembly

International audienceHepatitis C virus (HCV) envelope glycoprotein complex is composed of E1 and E2 subunits. E2 is the receptor-binding protein as well as the major target of neutralizing antibodies, whereas the functions of E1 remain poorly defined. Here, we took advantage of the recently published structure of the N-terminal region of the E1 ectodomain to interrogate the functions of this glycoprotein by mutating residues within this 79-amino-acid region in the context of an infectious clone. The phenotypes of the mutants were characterized to determine the effects of the mutations on virus entry, replication, and assembly. Furthermore, biochemical approaches were also used to characterize the folding and assembly of E1E2 heterodimers. Thirteen out of 19 mutations led to viral attenuation or inactivation. Interestingly, two attenuated mutants, T213A and I262A, were less dependent on claudin-1 for cellular entry in Huh-7 cells. Instead, these viruses relied on claudin-6, indicating a shift in receptor dependence for these two mutants in the target cell line. An unexpected phenotype was also observed for mutant D263A which was no longer infectious but still showed a good level of core protein secretion. Furthermore, genomic RNA was absent from these noninfectious viral particles, indicating that the D263A mutation leads to the assembly and release of viral particles devoid of genomic RNA. Finally, a change in subcellular colocalization between HCV RNA and E1 was observed for the D263A mutant. This unique observation highlights for the first time cross talk between HCV glycoprotein E1 and the genomic RNA during HCV morphogenesis

The key roles of economic and social organization, producer and consumer behaviour towards a Health-Agriculture-Food-Environment Nexus: recent advances and future prospects

We discuss in this paper the role of the economic and social organization in agriculture and the food industry, in relation with the Health-Agriculture-Food-Environment (HAFEN) concept. The aim is to better understand the potential impact of the implementation of this concept in food consumption and production systems in terms of research needs. The paper suggests a research agenda dedicated to the modes of social and economic organization of key stakeholders in the implementation of Nexus-based systems, facilitating the convergence among health, food and environmental objectives. Based on a literature survey, three main topics are discussed: a) processes and drivers of change of food consumption practices; b) co-ordination and multi-agent governance modes to better account for health issues in agrifood systems; c) the analysis of paradigms that put forward health as an entry point to reshape existing agricultural and food systems, and associated modes of knowledge production. For each of these topics, we suggest a selection of research priorities for the future and conclude with methodological perspectives on the HAFEN

Moving towards ecologically sustainable diets: Lessons from an Italian box delivery scheme

Conscious of the nutritional failings of the current food systems, there has been a call in the last decade or so to move beyond sustainable consumption and towards sustainable diets defined as healthy diets that also optimize the environment, food quality, socio‐cultural values, the economy and governance. Previous studies have shown how local food initiatives can lead to greater levels of sustainable consumption and healthier diets and have focused on the key role played by the conscious‐consumer. Analysing various types of local food initiatives—from community‐oriented to more private‐run activities—they have described the processes that local food initiatives set in motion to empower conscious‐consumers and to ultimately change habits and routines. Taking the specific case of a business‐oriented box delivery scheme in Italy, the article sheds further light on the mechanisms that enable clients to consume in more sustainable and healthier ways, with a central role played by learning, commitment and empowerment. Obstacles however exist in the form of the way people's everyday lives are structured, and the competing values that people draw upon in making their food choices. Support is therefore needed from public institutions to make it easier for people to choose healthier and more sustainable food provisioning systems

NMR structure and ion channel activity of the p7 protein from hepatitis C virus

The small membrane protein p7 of hepatitis C virus forms oligomers and exhibits ion channel activity essential for virus infectivity. These viroporin features render p7 an attractive target for antiviral drug development. In this study, p7 from strain HCV-J (genotype 1b) was chemically synthesized and purified for ion channel activity measurements and structure analyses. p7 forms cation-selective ion channels in planar lipid bilayers and at the single-channel level by the patch clamp technique. Ion channel activity was shown to be inhibited by hexamethylene amiloride but not by amantadine. Circular dichroism analyses revealed that the structure of p7 is mainly α-helical, irrespective of the membrane mimetic medium (e.g. lysolipids, detergents, or organic solvent/water mixtures). The secondary structure elements of the monomeric form of p7 were determined by 1H and 13C NMR in trifluoroethanol/water mixtures. Molecular dynamics simulations in a model membrane were combined synergistically with structural data obtained from NMR experiments. This approach allowed us to determine the secondary structure elements of p7, which significantly differ from predictions, and to propose a three-dimensional model of the monomeric form of p7 associated with the phospholipid bilayer. These studies revealed the presence of a turn connecting an unexpected N-terminal α-helix to the first transmembrane helix, TM1, and a long cytosolic loop bearing the dibasic motif and connecting TM1 to TM2. These results provide the first detailed experimental structural framework for a better understanding of p7 processing, oligomerization, and ion channel gating mechanism.Instituto de Física La Plat

Innovative solutions to sticky situations: Antiadhesive strategies for treating bacterial infections

ABSTRACT Bacterial adherence to host tissue is an essential process in pathogenesis, necessary for invasion and colonization and often required for the efficient delivery of toxins and other bacterial effectors. As existing treatment options for common bacterial infections dwindle, we find ourselves rapidly approaching a tipping point in our confrontation with antibiotic-resistant strains and in desperate need of new treatment options. Bacterial strains defective in adherence are typically avirulent and unable to cause infection in animal models. The importance of this initial binding event in the pathogenic cascade highlights its potential as a novel therapeutic target. This article seeks to highlight a variety of strategies being employed to treat and prevent infection by targeting the mechanisms of bacterial adhesion. Advancements in this area include the development of novel antivirulence therapies using small molecules, vaccines, and peptides to target a variety of bacterial infections. These therapies target bacterial adhesion through a number of mechanisms, including inhibition of pathogen receptor biogenesis, competition-based strategies with receptor and adhesin analogs, and the inhibition of binding through neutralizing antibodies. While this article is not an exhaustive description of every advancement in the field, we hope it will highlight several promising examples of the therapeutic potential of antiadhesive strategies.</jats:p