A DSL for multi-scale and autonomic software deployment

International audienceIn this paper, we present an ongoing work which aims at defining and experimenting a Domain-Specific Language (DSL) dedicated to multi-scale and autonomic software deployment. Autonomic software deployment in open environments is an open issue. There, the topology of target hosts is not always known due either to unforeseen hardware failures or limitations (network links, hosts, etc.) or to device arrival and disappearance. In a previous work, we proposed to describe deployment constraints using a DSL and then to satisfy them using a middleware for autonomic deployment, rather than classically building and executing a deployment plan. As deployment of multi-scale distributed systems demands the expression of specific constraints related to dimensions and scales, it is necessary to think over and define a new Domain-Specific Language. In this paper, we propose a new DSL designed to support the expression of constraints and properties related to multi-scale and autonomic software deployment

Formalisation de l'expression d'un plan de déploiement autonomique à base de contraintes

International audienceLes systèmes ambiants sont devenus massivement distribués. Le nombre d'appareils hétérogènes, et la variété de composants logiciels à déployer sur ces systèmes pour en assurer le bon fonctionnement ne cessent de croître. Leur topologie est en évolution constante, liée à l'apparition et la disparition des dispositifs mobiles. De ce fait, le déploiement de logiciel dans ces systèmes est un problème ouvert. Notre approche pour diminuer la complexité de cette opération, est le déploiement autonomique. Dans cet article, nous partons d'un langage dédié (DSL) nommé MuScADeL, pour lequel nous proposons une formalisation de l'expression du déploiement autonomique. Ensuite, nous montrons comment traduire les propriétés de déploiement en un problème de satisfaction de contraintes, et comment nous obtenons un plan de déploiement conforme qui sera enfin interprété par un intergiciel de déploiement autonomique

Récupération de l'état d'un domaine de déploiement.

Afin d'effectuer un déploiement autonomique, le système de déploiement a besoin de récupérer des informations (processeur, mémoire, connectivité, versions logicielles...) concernant les appareils constituant le domaine de déploiement. Dans cette démonstration, nous montrons notre prototype multiplateforme (y compris Android) de récupération de l'état du domaine

Two-dimensional topological superconductivity in Pb/Co/Si(111)

Just like insulators can host topological Dirac states at their edges, superconductors can also exhibit topological phases characterized by Majorana edge states. Remarkable zero-energy states have been recently observed at the two ends of proximity induced superconducting wires, and were interpreted as localized Majorana end states in one-dimensional (1D) topological superconductor. By contrast, propagating Majorana states should exist at the 1D edges of two-dimensional (2D) topological superconductors. Here we report the direct observation of dispersive in-gap states surrounding topological superconducting domains made of a single atomic layer of Pb covering magnetic islands of Co/Si(111). We interpret the observed continuous dispersion across the superconducting gap in terms of a spatial topological transition accompanied by a chiral edge mode and residual gaped helical edge states. Our experimental approach enables the engineering and control of a large variety of novel quantum phases. This opens new horizons in the field of quantum materials and quantum electronics where the magnetization of the domains could be used as a control parameter for the manipulation of topological states.Comment: 12 pages, 3 figure

Contribution à la formalisation des propriétés graphiques des systèmes interactifs pour la validation automatique

International audienceDans la plupart des secteurs, les systèmes d'aujourd'hui sont interactifs et disposent d'in-terfaces graphiques sophistiquées. A notre connaissance, il existe peu d'études sur la vérifi-cation des propriétés spécifiques de la scène graphique des interfaces homme-machine et en particulier sur celles liées à la visibilité des composants graphiques par l'utilisateur humain. Dans ce papier, nous introduisons notre formalisme permettant de spécifier certaines proprié-tés des composants graphiques, dans l'objectif de réaliser à terme un outillage de validation automatique de ces propriétés. Nous illustrons l'usage de ce formalisme pour des propriétés extraites d'une norme décrivant un instrument critique présent dans les cockpits d'avions com-merciaux. Nous avons développé une version complètement fonctionnelle de cet instrument au moyen de Smala, un langage interactif de haut niveau produit par notre équipe. Cela nous permet de montrer la manière dont nous envisageons les opérations de validation formelle automatique de propriétés graphiques de tels systèmes

OSIF: A Framework To Instrument, Validate, and Analyze Simulations

International audienceIn most existing simulators, the outputs of a simulation run consist either in a simulat ion report generated at the end of the run and summarizing the statistics of interest, or in a (set of) trace file(s) containing raw data samples produced and saved regularly during the run, for later post-processing. In this paper, we address issues related to the management of these data and their on-line processing, such as: (i)~the instrumentation code is mixed in the modeling code; (ii)~the amount of data to be stored may be enormous, and often, a significant part of these data are useless while their collect may consume a significant amount of the computing resources; and (iii)~it is difficult to have confidence in the treatment applied to the data and then make comparisons between studies since each user (model developer) builds its own ad-hoc instrumentation and data processing. In this paper, we propose OSIF, a new component-based instrumentation framework designed to solve the above mentioned issues. OSIF is based on several mature software engineering techniques and frameworks, such as COSMOS, Fractal and its ADL, and AOP

Projet INCOME : INfrastructure de gestion de COntexte Multi-Echelle pour l'Internet des Objets

International audienceCet article donne un aperçu du projet de recherche INCOME financé par l'Agence Nationale de la Recherche française en décrivant la fiche d'identité du projet, ses principaux enjeux scientifiques ainsi que les premiers résultats obtenus

Gestion de contexte multi-échelle pour l'Internet des objets

Cet article présente une architecture logicielle de gestion de contexte multi-échelle pour l'Internet des objets. Nous présentons d'abord quelques défis spécifiques auxquels est confrontée cette nouvelle génération d'intergiciels, tels que la communication répartie en modes push et pull, la sensibilité multi-échelle, et la réponse à des exigences et des garanties de qualité de l'information de contexte et de respect de la vie privée. Nous donnons ensuite la vision du projet INCOME pour répondre à ces défis en fournissant une infrastructure répartie de gestion de contexte et en assurant son déploiement de manière autonomique

Export of a Toxoplasma gondii Rhoptry Neck Protein Complex at the Host Cell Membrane to Form the Moving Junction during Invasion

One of the most conserved features of the invasion process in Apicomplexa parasites is the formation of a moving junction (MJ) between the apex of the parasite and the host cell membrane that moves along the parasite and serves as support to propel it inside the host cell. The MJ was, up to a recent period, completely unknown at the molecular level. Recently, proteins originated from two distinct post-Golgi specialised secretory organelles, the micronemes (for AMA1) and the neck of the rhoptries (for RON2/RON4/RON5 proteins), have been shown to form a complex. AMA1 and RON4 in particular, have been localised to the MJ during invasion. Using biochemical approaches, we have identified RON8 as an additional member of the complex. We also demonstrated that all RON proteins are present at the MJ during invasion. Using metabolic labelling and immunoprecipitation, we showed that RON2 and AMA1 were able to interact in the absence of the other members. We also discovered that all MJ proteins are subjected to proteolytic maturation during trafficking to their respective organelles and that they could associate as non-mature forms in vitro. Finally, whereas AMA1 has previously been shown to be inserted into the parasite membrane upon secretion, we demonstrated, using differential permeabilization and loading of RON-specific antibodies into the host cell, that the RON complex is targeted to the host cell membrane, where RON4/5/8 remain associated with the cytoplasmic face. Globally, these results point toward a model of MJ organization where the parasite would be secreting and inserting interacting components on either side of the MJ, both at the host and at its own plasma membranes

Autophagy Protein Atg3 is Essential for Maintaining Mitochondrial Integrity and for Normal Intracellular Development of Toxoplasma gondii Tachyzoites

Autophagy is a cellular process that is highly conserved among eukaryotes and permits the degradation of cellular material. Autophagy is involved in multiple survival-promoting processes. It not only facilitates the maintenance of cell homeostasis by degrading long-lived proteins and damaged organelles, but it also plays a role in cell differentiation and cell development. Equally important is its function for survival in stress-related conditions such as recycling of proteins and organelles during nutrient starvation. Protozoan parasites have complex life cycles and face dramatically changing environmental conditions; whether autophagy represents a critical coping mechanism throughout these changes remains poorly documented. To investigate this in Toxoplasma gondii, we have used TgAtg8 as an autophagosome marker and showed that autophagy and the associated cellular machinery are present and functional in the parasite. In extracellular T. gondii tachyzoites, autophagosomes were induced in response to amino acid starvation, but they could also be observed in culture during the normal intracellular development of the parasites. Moreover, we generated a conditional T. gondii mutant lacking the orthologue of Atg3, a key autophagy protein. TgAtg3-depleted parasites were unable to regulate the conjugation of TgAtg8 to the autophagosomal membrane. The mutant parasites also exhibited a pronounced fragmentation of their mitochondrion and a drastic growth phenotype. Overall, our results show that TgAtg3-dependent autophagy might be regulating mitochondrial homeostasis during cell division and is essential for the normal development of T. gondii tachyzoites