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International audience; Early detection of damage and monitoring helps improving the safety and durability of structures. The ability to model and simulate this phenomenon, along with measurements, facilitates system control.Various sensor types have been used in the context of structural health monitoring. Among them, Distributed Optic Fiber Sensors grant certain benefits which make them a convenient option for real-time monitoring of structures. This work comprises of using distributed strain sensors, based on Rayleigh backscattering and OFDR technology, in samples that bear loading up to their failure point. The collected data are then post-processed in the framework of modified constitutive relation error (mCRE) to perform damage model updating and estimate the material condition. Several damage models are presented and compared, and the most suitable model is also selected using mCRE.; La détection précoce de l’endommagement et le suivi de sa progression contribuent à améliorer la sécurité et la durabilité des structures. La capacité à modéliser et simuler ce phénomène, en complément de mesures, facilite le contrôle du système. Différents types de capteurs ont été utilisés dans le cadre de la surveillance de l’état des structures. Parmi eux, les capteurs à fibre optique distribués offrent divers avantages qui en font une option pratique pour la surveillance en temps réel des structures. Ce travail consiste à utiliser des capteurs distribués de déformation, basés sur la rétrodiffusion de Rayleigh et la technologie OFDR, dans des échantillons qui supportent une charge jusqu’à leur point de rupture. Les données recueillies sont ensuite post-traitées dans le cadre de l’erreur en relation de comportement modifiée (mCRE) pour effectuer la mise à jour du modèle d’endommagement et estimer l’état du matériau.Plusieurs modèles d’endommagement sont présentés et comparés, et le modèle le plus adapté est aussi sélectionné au moyen de la mCRE.

This paper is a review on distributed optic fiber sensing for structural health monitoring applications, with a focus on technologies relying on the Rayleigh backscattering phenomenon. It addresses the basic physical principles which are involved, the implementation and instrumentation of the measurement techniques, as well as recent practical applications, current performance, and remaining challenges. Being written at an elementary level and integrating relevant theoretical and technical details, we hope the document can be useful for researchers and engineers looking for an up-to-date overview on a field which currently undergoes significant development and increasing attractiveness, in particular for damage tracking in complex mechanical structures.

See Karakaya and Wirth (doi:10.1093/brain/awz273) for a scientific commentary on this article. Neurofascin (NFASC) isoforms are immunoglobulin cell adhesion molecules involved in node of Ranvier assembly. Efthymiou et al. identify biallelic NFASC variants in ten unrelated patients with a neurodevelopmental disorder characterized by variable degrees of central and peripheral involvement. Abnormal expression of Nfasc155 is accompanied by severe loss of myelinated fibres., Axon pathfinding and synapse formation are essential processes for nervous system development and function. The assembly of myelinated fibres and nodes of Ranvier is mediated by a number of cell adhesion molecules of the immunoglobulin superfamily including neurofascin, encoded by the NFASC gene, and its alternative isoforms Nfasc186 and Nfasc140 (located in the axonal membrane at the node of Ranvier) and Nfasc155 (a glial component of the paranodal axoglial junction). We identified 10 individuals from six unrelated families, exhibiting a neurodevelopmental disorder characterized with a spectrum of central (intellectual disability, developmental delay, motor impairment, speech difficulties) and peripheral (early onset demyelinating neuropathy) neurological involvement, who were found by exome or genome sequencing to carry one frameshift and four different homozygous non-synonymous variants in NFASC. Expression studies using immunostaining-based techniques identified absent expression of the Nfasc155 isoform as a consequence of the frameshift variant and a significant reduction of expression was also observed in association with two non-synonymous variants affecting the fibronectin type III domain. Cell aggregation studies revealed a severely impaired Nfasc155-CNTN1/CASPR1 complex interaction as a result of the identified variants. Immunofluorescence staining of myelinated fibres from two affected individuals showed a severe loss of myelinated fibres and abnormalities in the paranodal junction morphology. Our results establish that recessive variants affecting the Nfasc155 isoform can affect the formation of paranodal axoglial junctions at the nodes of Ranvier. The genetic disease caused by biallelic NFASC variants includes neurodevelopmental impairment and a spectrum of central and peripheral demyelination as part of its core clinical phenotype. Our findings support possible overlapping molecular mechanisms of paranodal damage at peripheral nerves in both the immune-mediated and the genetic disease, but the observation of prominent central neurological involvement in NFASC biallelic variant carriers highlights the importance of this gene in human brain development and function.

Food Consumption and its Evolution in Kinshasa, Democratic Republic of the Congo.Food consumption in urban areas is changing and diversifying. The analysis of changes in eating habits of Kinshasa inhabitants reflects of a specific culture tied to the history of the formation and evolution of social, economic and cultural identities. This article is a response to the questions: How gauge changing culinary and dietary practices in Kinshasa? What are the innovations and trends in food consumption patterns in Kinshasa? It rests on the analysis of various studies on food consumption conducted in Kinshasa. After a brief introduction to the plurality and diversity of consumer references in Kinshasa, it describes the telltale signs of changing dietary and culinary practices, by presenting the history of the changes. Kinshasa cuisine has developed on the basis of pre-colonial, colonial and more recently global cultural influences. Current trends show that the population of Kinshasa seeks to adapt by focusing more on some innovations. These relate to both the design of new \"Urban Menu\" food and the evolution of traditional dishes. These innovations also involve the use of catering, supermarkets and food supply practices considered \"alternative\" to the \"traditional\" practice., La consommation alimentaire en milieu urbain évolue et se diversifie. L’analyse du changement des habitudes alimentaires des Kinois rend compte d’une culture propre liée à l’histoire de la formation et de l’évolution des identités sociales, économiques et culturelles. Cet article se veut une réponse aux questions: Comment cerner l’évolution des pratiques culinaires et alimentaires à Kinshasa? Quelles sont les innovations et les tendances actuelles dans les modes de consommation alimentaires à Kinshasa? Il s’appuie sur l’analyse de diverses études sur la consommation alimentaire réalisées à Kinshasa. Après une brève introduction à la pluralité et diversité des références des consommateurs de la ville de Kinshasa, il décrit les signes révélateurs de l’évolution des pratiques culinaires et alimentaires, en présentant l’histoire des changements intervenus. La cuisine kinoise s’est élaborée sur la base d’influences culturelles, précoloniales, coloniales et plus récemment mondiales. Les tendances actuelles montrent que les populations kinoises cherchent à s’adapter en mettant davantage l’accent sur quelques innovations. Celles-ci concernent à la fois la conception de nouveaux aliments «menu urbain» et l’évolution des mets traditionnels. Ces innovations concernent aussi le recours à la restauration hors-foyer, aux «supermarchés» et aux pratiques d’approvisionnement alimentaires considérées comme «alternatives» à la pratique «traditionnelle».

International audience; no abstract

International audience; no abstract

International audience; no abstract

International audience; no abstract

Identification of Degradation Indicators of Tapia Forest (Uapaca bojeri) by Sylvicultural Analysis. Une étude des effets de lisière sur les sex-ratios de six espèces de rongeurs a été abordée dans la Réserve de Masako à 15 km de Kisangani en RDC. Une collection de 1789 individus capturés durant deux ans a permis d'analyser les sex-ratios dans la jachère, la forêt secondaire et la lisière jachère/forêt secondaire. Les résultats ont été comparés à une distribution uniforme à l'aide du test χ². Les mâles ont été plus capturés chez toutes les espèces, sauf chez Lophuromys dudui. Un sexratio global significativement en faveur des mâles est observé d'une année à l'autre. Globalement, le sex-ratio n'est pas statistiquement différent de 1/1 chez Deomys, Hybomys et Lophuromys mais significativement supérieur à 1/1 chez Hylomyscus et Stochomys. Chez Praomys, il est significativement supérieur à 1/1 en 2010 mais pas en 2011. Les mâles de Hylomyscus, Praomys et Stochomys et les femelles de Lophuromys ont été plus abondants dans les trois habitats. La lisière a été caractérisée par une dominance des femelles de Deomys et des sex-ratios non différents de 1/1 chez Hylomyscus, mais significativement plus grands que 1/1 chez Praomys et Stochomys. La différence de sex-ratio entre la lisière et ses habitats adjacents chez Hylomyscus, Praomys et Stochomys prouve un effet de lisière.

article lié au prix de thèse discerné au congrès TINCE 2016; International audience; The knowledge of the concrete behavior is essential when analyzing the aging and leakage phenomena of production facilities. On the industrial level the concrete fracture characterization is currently performed through standard experimental tests that are not sufficiently rich to determine in an optimized manner all the corresponding characteristics. First there is a general lack of mixed mode loading experiments that produce non trivial crack paths. Moreover, even for some well defined material properties (as for example critical shear stress) the corresponding loading tests are not sufficiently developed, as the results are too dependent on aggregate distribution and specimen sizes. It means that we are still not able to locally reproduce some specific me-chanical stresses distribution and repeatedly check it in order to attain necessary accuracy. Therefore an improvement in corresponding measurement technique is still needed.When studying concrete fracture behavior the main difficulty is related to instable crack propagation. In the past some relevant works in mixed mode fracture were conducted by Nooru-Mohamed. More recently the work was extended employing an up-to-date full-field measurement technique.In this work, we develop a stable crack path control technique that allows “customized” cracking tests creation for the characterization of various materials. Using this technique well instrumented and discriminating mixed–mode crack propagation tests performed on VERCORS concrete samples are presented. Finally we discuss the relevance of these tests for various pa-rameters identification and some possible extension of stable crack path control technique.

Borocera cajani or "Landibe" (vernacular name) is the wild silk moth that is currently used to produce silk textiles in Madagascar. This species is endemic to Madagascar, and is distributed throughout the island, colonizing the Uapaca bojeri or "Tapia" forest of the central highlands. The forest provides food in the form of plants for B. cajani, including U. bojeri leaves. The species secretes silk at the onset of pupation and for making cocoons. Borocera cajani and its natural habitat are threatened by human destruction, such as bush fires, firewood collection, charcoal production, and the over-harvesting of their cocoons. Wild silk production largely disappeared when the silk industry utilized many people on the island as the collectors of cocoons, spinners, dyers, weavers, and artists who transform the silk into clothes, accessories, and objects. Therefore, it is important to study the biology of B. cajani to revitalize silk production in a way that helps conserve this species and the Tapia forest.