A Generic API for Load Balancing in Structured P2P Systems

International audienceReal world datasets are known to be highly skewed, often leading to an important load imbalance issue for distributed systems managing them. To address this issue, there exist almost as many load balancing strategies as there are different systems. When designing a scalable distributed system geared towards handling large amounts of information, it is often not so easy to anticipate which kind of strategy will be the most efficient to maintain adequate performance regarding response time, scalability and reliability at any time. Based on this observation, we describe the methodology behind the building of a generic API to implement and experiment any strategy independently from the rest of the code, prior to a definitive choice for instance. We then show how this API is compatible with famous existing systems and their load balancing scheme. We also present results from our own distributed system which targets the continuous storage of events structured according to the Semantic Web standards, further retrieved by interested parties. As such, our system constitutes a typical example of a Big Data environment

The Microvine: A Versatile Plant Model to Boost Grapevine Studies in Physiology and Genetics

The microvine is a grapevine somatic variant. The Vvgai1 mutation results in a miniaturization of the vegetative organs of the plant keeping fruit size intact and a systematic conversion of tendrils into inflorescences. The physiological characterization of the vegetative and reproductive development of the microvine makes it possible to infer kinetic data from spatial phenotypes. This biological model allows experiments on vine and grape development in tightly controlled conditions, which greatly accelerate physiology, molecular biology, as well as genetic studies. After introducing the main biological properties of the microvine, main results from various research programs performed with the microvine model will be presented

Modular P2P-Based Approach for RDF Data Storage and Retrieval

International audienceOne of the key elements of the Semantic Web is the Resource Description Framework (RDF). Efficient storage and retrieval of RDF data in large scale settings is still challenging and existing solutions are monolithic and thus not very flexible from a software engineering point of view. In this paper, we propose a modular system, based on the scalable Content-Addressable Network (CAN), which gives the possibility to store and retrieve RDF data in large scale settings. We identified and isolated key components forming such system in our design architecture. We have evaluated our system using the Grid'5000 testbed over 300 peers on 75 machines and the outcome of these micro-benchmarks show interesting results in terms of scalability and concurrent queries

Is transcriptomic regulation of berry development more important at night than during the day?

Diurnal changes in gene expression occur in all living organisms and have been studied on model plants such as Arabidopsis thaliana. To our knowledge the impact of the nycthemeral cycle on the genetic program of fleshly fruit development has been hitherto overlooked. In order to circumvent environmental changes throughout fruit development, young and ripening berries were sampled simultaneously on continuously flowering microvines acclimated to controlled circadian light and temperature changes. Gene expression profiles along fruit development were monitored during both day and night with whole genome microarrays (Nimblegen® vitis 12x), yielding a total number of 9273 developmentally modulated probesets. All day-detected transcripts were modulated at night, whereas 1843 genes were night-specific. Very similar developmental patterns of gene expression were observed using independent hierarchical clustering of day and night data, whereas functional categories of allocated transcripts varied according to time of day. Many transcripts within pathways, known to be up-regulated during ripening, in particular those linked to secondary metabolism exhibited a clearer developmental regulation at night than during the day. Functional enrichment analysis also indicated that diurnally modulated genes considerably varied during fruit development, with a shift from cellular organization and photosynthesis in green berries to secondary metabolism and stress-related genes in ripening berries. These results reveal critical changes in gene expression during night development that differ from daytime development, which have not been observed in other transcriptomic studies on fruit development thus far. © 2014 Rienth et al.This work is part of the DURAVITIS program which is financially supported by the ANR (Agence national de la recherche) -Genopole (project ANR-2010-GENM-004-01) and the Jean Poupelain foundation (30 Rue Gâte Chien, 16100 Javrezac, France).Peer Reviewe

Speech Technologies for African Languages: Example of a Multilingual Calculator for Education

International audienceThis paper presents our achievements after 18 months of the ALFFA project dealing with African languages technologies. We focus on a multilingual calculator (Android app) that will be demonstrated during the Show and Tell session

Efficient Data-Intensive Event-Driven Interaction in SOA

International audienceThis paper presents a middleware that enables the efficient delivery of events carrying large attachments. We transpar- ently decouple event-description from event-data, in order to avoid useless data-transfers and modifications to endpoints business logic. Our solution relieves the event-delivery sys- tem of large data transfers, by enabling direct, but trans- parent, publisher to subscriber data-exchange. The experi- ments show that we can reduce the average event delivery time by half, compared to a standard approach requiring the full mediation of the event-delivery system

Chapitre 5. L’époque moderne

Entre la fin de l’activité agricole, phase 4B/C datable du milieu du Ve siècle apr. J.-C., et la reprise d’une installation au début de l’époque moderne, aucune trace d’occupation ni même de fréquentation n’a été perçue sur le site, qui paraît totalement abandonné durant près d’un millénaire. La découverte d’un fragment de bol à la croix en céramique pisane caractéristique du XIVe siècle (Amouric et al. 1999, 30) ne peut à elle seule indiquer une reprise de l’activité sur le site durant le ba..

Magnetic/Silica Nanocomposites as Dual-Mode Contrast Agents for Combined Magnetic Resonance Imaging and Ultrasonography.

A simple and effi cient method for synthesizing a range of hybrid nanocomposites based on a core of silica nanospheres (160, 330, and 660 nm in diameter) covered by an outer shell of superparamagnetic nanoparticles, either iron oxide or heterodimeric FePt-iron oxide nanocrystals, is presented. The magnetic and ultrasound characterization of the resulting nanocomposites shows that they have great potential as contrast agents for dual-mode imaging purposes, combining magnetic resonance imaging (MRI) and ultrasonography (US)

Conclusion. Synthèse archéologique et analyses paléoenvironnementales

1. L’archéologie (P. E.) Par la nature de ses découvertes, la fouille de Villa Romana a permis d’apporter des données entièrement nouvelles sur l’environnement d’un quartier suburbain de Forum Iulii en fournissant un cadre naturel à des vestiges bâtis relativement denses. La position du littoral et son recul rapide ont fortement influé sur le développement de ce secteur et lui ont conféré une place de choix, en particulier durant les premiers temps de la colonisation. Ces travaux ont été égal..

Chapitre 3. Les abords des thermes de Villeneuve durant la deuxième moitié du Ier siècle apr. J.‑C.

1. La phase 3, état A Les vestiges en rapport avec cette phase concernent essentiellement les zones 1 et 3. Comme durant la phase précédente, la bande centrale (zone 2) est un terrain sableux exhaussé, dont les niveaux d’occupation ont totalement disparu. Il en est de même pour une partie de la zone 3, excavée lors des phases suivantes, mais la présence de structures situées sous les sols permet de retrouver la trace de quelques aménagements (fig. 58). 1.1. La zone 1 (P. E.) 1.1.1. Descripti..