Embedded Software V&V using Virtual Platforms for Powertrain applications

International audienceCurrent development trends for automotive products are driven by time to market reduction, cost optimization, and quality improvement. Dual to these business constraints are demands for innovation and safety conformance which impose increasing complexity on embedded systems. To address these challenges impacting software and hardware to improve system dependability, new methodology and tools need to be set-up. The use of representative virtual platforms combining speed and accuracy allows earlier software development, improved system testing, and fault injection analysis, with a high potential for reuse of system IPs (including both hardware and software). In this paper, we will present investigation on new methods and associated results using a simplified virtual platform to test a powertrain application

Agrégations familiales de la structure et de la qualité du sommeil dans la cohorte SKIPOGH

Introduction Très peu de données sont disponibles concernant l’héritabilité de la structure et de la qualité du sommeil et aucune étude en particulier n’a été faite au sujet d’agrégations familiales des caractéristiques du sommeil en utilisant une analyse en cluster. Nous avons essayé de déterminer s’il existe des agrégations de la structure et de la qualité du sommeil plus importantes entre les membres d’une même famille que parmi les participants non apparentés. Méthode Grâce à l’étude SKIPOGH, nous disposons d’enregistrements polysomnographiques du sommeil de 195 personnes regroupées en clusters familiaux ainsi qu’un questionnaire concernant leur sommeil. Nous avons ensuite utilisé les données polysomnographiques de la cohorte de la population générale HypnoLaus pour tenter de confirmer les résultats obtenus avec la cohorte SKIPOGH. Deux méthodes d’analyse statistique ont été utilisées, la première en utilisant les données polysomnographiques de la cohorte SKIPOGH et la deuxième en utilisant les données polysomnographiques de la cohorte HypnoLaus. Deux modèles de normalisation ont également été appliqués, le premier en normalisant pour l’âge et le sexe et le deuxième en normalisant pour l’âge, le sexe et en effectuant une « winsorisation » permettant de faire abstraction des valeurs extrêmes. Résultats Nous avons observé une héritabilité de la structure du sommeil variant de 34 à 89% en fonction des bandes de fréquences de l’électroencéphalogramme et des stades du sommeil. Les héritabilités les plus élevées ont été retrouvées dans le stade 2 du sommeil (N2) et dans le sommeil non-REM. Concernant les bandes de fréquences, les ondes alpha, beta, thêta et sigma sont les plus héritables. Les ondes delta semblent globalement moins héritables. Les héritabilités les plus élevés concernent les ondes alpha, thêta et lowsigma lors du stade 2 du sommeil avec respectivement 81%, 89% et 86%, ainsi que les ondes beta et lowsigma pendant le sommeil non-REM avec respectivement 85% et 88%. Le score à l’échelle de somnolence d’Epworth est héritable à hauteur d’environ 52%. Concernant les troubles respiratoires au cours du sommeil, nous retrouvons une forte héritabilité des index de désaturation d’oxygène 3%, ODI 4% et ODI 6% à hauteur de respectivement 67%, 60-72% et 38-45%. Finalement, les résultats concernant les mouvements périodiques des jambes au cours du sommeil sont également significatifs avec une héritabilité de 48 à 53 % selon le modèle de normalisation utilisé. Conclusion Certains patterns de l’architecture du sommeil semblent être fortement influencés par le patrimoine génétique sous-jacent. Cette influence semble également concerner d’autres 4 problèmes liés au sommeil comme les troubles respiratoires nocturnes, les mouvements périodiques des jambes ainsi que les plaintes de somnolence diurne

Applying Model Based Techniques for Early Safety Evaluation of an Automotive Architecture in Compliance with the ISO 26262 Standard

International audienceIn 2011, the automotive industry introduced the application of a standardized process for functional safety-related development of automotive electronic products. The related international standard, ISO 26262 functional safety for road vehicles, has high demands on process documentation and analysis. Within an engineering context this challenges the tremendous increase of complexity for modern automotive systems and high productivity demands for industrial competiveness purpose. Model based development techniques based on an Architecture Description Language (ADL) has been identified as the best candidate to manage the system complexity and the related safety analysis with the benefit of formal description and capabilities for test automation. The proposed concept relies on the definition of a compositional error modeling approach tightly coupled with the system architecture model, capable to analyze the software and hardware architectures and implementations. This paper explains the results of the language extension based on the EAST-ADL and AUTOSAR domain model in terms of early safety evaluation of an automotive architecture, automating the qualitative and quantitative assessment of road vehicle products as claimed by the application of the ISO 26262

Developing Automotive Products Using the EAST-ADL2, an AUTOSAR Compliant Architecture Description Language

International audienceCurrent development trends in automotive software feature increasing standardization of the embedded software structure. But it still remains the critical issue of the overall engineering information management to control the system definition and manage its complexity. System modeling based onan Architecture Description Language (ADL) is a way to keep these assets within one information structure. The original EAST-ADL was developed in the EAST-EEA project (www.east-eea.org) and basic concepts were reused in the AUTOSAR standardization initiative. The original EAST-ADL is currently refined in the ATESST project (www.atesst.org) to EAST-ADL2. This paper presents the results of the language extension provided by the EAST-ADL2 domain model and focuses on its possible extension of the AUTOSAR standard to support decomposition of E/E automotive systems

Cell wall changes during maturation of conidia in Pseudallescheria boydii

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Cell wall modifications during conidial maturation of the human pathogenic fungus Pseudallescheria boydii

This is the final version of the article. Available from the publisher via the DOI in this record.Progress in extending the life expectancy of cystic fibrosis (CF) patients remains jeopardized by the increasing incidence of fungal respiratory infections. Pseudallescheria boydii (P. boydii), an emerging pathogen of humans, is a filamentous fungus frequently isolated from the respiratory secretions of CF patients. It is commonly believed that infection by this fungus occurs through inhalation of airborne conidia, but the mechanisms allowing the adherence of Pseudallescheria to the host epithelial cells and its escape from the host immune defenses remain largely unknown. Given that the cell wall orchestrates all these processes, we were interested in studying its dynamic changes in conidia as function of the age of cultures. We found that the surface hydrophobicity and electronegative charge of conidia increased with the age of culture. Melanin that can influence the cell surface properties, was extracted from conidia and estimated using UV-visible spectrophotometry. Cells were also directly examined and compared using electron paramagnetic resonance (EPR) that determines the production of free radicals. Consistent with the increased amount of melanin, the EPR signal intensity decreased suggesting polymerization of melanin. These results were confirmed by flow cytometry after studying the effect of melanin polymerization on the surface accessibility of mannose-containing glycoconjugates to fluorescent concanavalin A. In the absence of melanin, conidia showed a marked increase in fluorescence intensity as the age of culture increased. Using atomic force microscopy, we were unable to find rodlet-forming hydrophobins, molecules that can also affect conidial surface properties. In conclusion, the changes in surface properties and biochemical composition of the conidial wall with the age of culture highlight the process of conidial maturation. Mannose-containing glycoconjugates that are involved in immune recognition, are progressively masked by polymerization of melanin, an antioxidant that is commonly thought to allow fungal escape from the host immune defenses.The study was funded by “Région Pays de la Loire” in the frame of “Myco-AFM” research program). BED was supported by the Dutch Virgo Consortium (FES0908, NGI 050-060-452) and CAPES/BRASIL. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Cell wall modifications during maturation and germination of the conidia in the opportunistic fungus Scedosporium apiospermum

Introduction: Recent prevention measures led to an increase in life expectancy of cystic fibrosis (CF) patients; however, this progress remained jeopardized by various microbial infections. Scedosporium apiospermum is the second most frequent filamentous fungus found in the respiratory tract of CF patients. Unlike other infectious agents, the pathogenic mechanisms of this fungus are far less studied. We aim through this project to study the life cycle and the cell surface composition in order to set the basis for understanding the adherence mechanisms of S. apiospermum inside a human host. Results: So far, we have studied the cell wall modifications during maturation and germination of spores. Germination was studied in yeast peptone dextrose (YPD) broth and malt medium at different temperatures (20 C, 25 C and 37 C). The highest percentage of germination was obtained in YPD at 37 C, conditions which were selected for further experiments. The comparison of spores collected from 5-, 9- or 14 day-old cultures showed that spores from 9 day-old cultures exhibited the highest percentage of germination, capacity to bind concanavalin A (Con A) and cell-surface hydrophobicity (CSH), and the lowest electrostatic charge. Electron microscopy showed that the cell wall of S. apiospermum conidia is composed of two layers (electron-dense outer layer and electron transparent inner layer). Germination resulted in a thinner and fibrillar outer layer that was occasionally detached upon elongation of the filament. These ultra-structural changes were substantiated with fluorescent microscopy; the hyphal part was intensely labeled by Con-A and wheat germ agglutinin (WGA) in contrast to the mother cell. Furthermore, germination resulted in a remarkable decrease in the surface electronegativity and CSH.   Conclusion: We demonstrated that S. apiospermum spores undergo maturation. Spores isolated from cultures of different age differ in their capacity to germinate, their surface accessibility to Con A and their surface physical properties (CSH and electronegativity). Upon germination, a thinning of the outer cell wall layer is observed, rendering the inner layer more accessible to lectins (Con A and WGA) and resultingin a reduced CSH and electronegative charge. All these results point out that the cell wall in S. apiospermum is a dynamic structure and the variability in its properties and composition might affect its adherence to the host tissues