Reversible Rail Shear Apparatus Applied to the Study of Woven Laminate Shear Behavior

The multitude of in-plane shear tests existing in the literature seems to demonstrate the complexity of developing a test adapted to all experimental works. In a general framework of investigation of translaminar cracks in thin laminates, a test able to reproduce a pure in-plane shear loading was required. The laminate studied is notably employed as helicopter blade skin, and cyclic torsion induced by aerodynamic load involves cyclic in-plane shear. This particular application established some specifications for the test needed to carry out this study. To comply with them, an original technological solution has been developed from a three-rail shear test apparatus. This paper describes the resulting “reversible rail shear test” solution and its application to the study of in-plane shear behavior of a thin glass-epoxy laminate. The results concern plain and notched coupons under quasi-static loading, and crack growth tests under cyclic loading

Integer Functions Suitable for Homomorphic Encryption over Finite Fields

Fully Homomorphic Encryption (FHE) gives the ability to evaluate any function over encrypted data. However, despite numerous improvements during the last decade, the computational overhead caused by homomorphic computations is still very important. As a consequence, optimizing the way of performing the computations homomorphically remains fundamental. Several popular FHE schemes such as BGV and BFV encode their data, and thus perform their computations, in finite fields. In this work, we study and exploit algebraic relations occurring in prime characteristic allowing to speed-up the homomorphic evaluation of several functions over prime fields. More specifically we give several examples of unary functions: modulo , is power of $b$ , Hamming weight and Mod2\u27 whose homomorphic evaluation complexity over $\mathbb{F}_p$ can be reduced from the generic bound $\sqrt{2p} + \mathcal{O}(\log(p))$ homomorphic multiplications, to $\sqrt{p} + \mathcal{O}(\log(p))$, $\mathcal{O}(\log (p))$, $\mathcal{O}(\sqrt{p/\log (p)})$ and $\mathcal{O}(\sqrt{p/\log (p)})$ respectively. Additionally we provide a proof of a recent claim regarding the structure of the polynomial interpolation of the less-than bivariate function which confirms that this function can be evaluated in $2p-6$ homomorphic multiplications instead of $3p-5$ over $\mathbb{F}_p$ for $p\geq 5$

PHENOPSIS DB: an Information System for Arabidopsis thaliana phenotypic data in an environmental context

<p>Abstract</p> <p>Background</p> <p>Renewed interest in plant × environment interactions has risen in the post-genomic era. In this context, high-throughput phenotyping platforms have been developed to create reproducible environmental scenarios in which the phenotypic responses of multiple genotypes can be analysed in a reproducible way. These platforms benefit hugely from the development of suitable databases for storage, sharing and analysis of the large amount of data collected. In the model plant <it>Arabidopsis thaliana</it>, most databases available to the scientific community contain data related to genetic and molecular biology and are characterised by an inadequacy in the description of plant developmental stages and experimental metadata such as environmental conditions. Our goal was to develop a comprehensive information system for sharing of the data collected in PHENOPSIS, an automated platform for <it>Arabidopsis thaliana </it>phenotyping, with the scientific community.</p> <p>Description</p> <p>PHENOPSIS DB is a publicly available (URL: <url>http://bioweb.supagro.inra.fr/phenopsis/</url>) information system developed for storage, browsing and sharing of online data generated by the PHENOPSIS platform and offline data collected by experimenters and experimental metadata. It provides modules coupled to a Web interface for (i) the visualisation of environmental data of an experiment, (ii) the visualisation and statistical analysis of phenotypic data, and (iii) the analysis of <it>Arabidopsis thaliana </it>plant images.</p> <p>Conclusions</p> <p>Firstly, data stored in the PHENOPSIS DB are of interest to the <it>Arabidopsis thaliana </it>community, particularly in allowing phenotypic meta-analyses directly linked to environmental conditions on which publications are still scarce. Secondly, data or image analysis modules can be downloaded from the Web interface for direct usage or as the basis for modifications according to new requirements. Finally, the structure of PHENOPSIS DB provides a useful template for the development of other similar databases related to genotype × environment interactions.</p

SPODOBASE : an EST database for the lepidopteran crop pest Spodoptera

BACKGROUND: The Lepidoptera Spodoptera frugiperda is a pest which causes widespread economic damage on a variety of crop plants. It is also well known through its famous Sf9 cell line which is used for numerous heterologous protein productions. Species of the Spodoptera genus are used as model for pesticide resistance and to study virus host interactions. A genomic approach is now a critical step for further new developments in biology and pathology of these insects, and the results of ESTs sequencing efforts need to be structured into databases providing an integrated set of tools and informations. DESCRIPTION: The ESTs from five independent cDNA libraries, prepared from three different S. frugiperda tissues (hemocytes, midgut and fat body) and from the Sf9 cell line, are deposited in the database. These tissues were chosen because of their importance in biological processes such as immune response, development and plant/insect interaction. So far, the SPODOBASE contains 29,325 ESTs, which are cleaned and clustered into non-redundant sets (2294 clusters and 6103 singletons). The SPODOBASE is constructed in such a way that other ESTs from S. frugiperda or other species may be added. User can retrieve information using text searches, pre-formatted queries, query assistant or blast searches. Annotation is provided against NCBI, UNIPROT or Bombyx mori ESTs databases, and with GO-Slim vocabulary. CONCLUSION: The SPODOBASE database provides integrated access to expressed sequence tags (EST) from the lepidopteran insect Spodoptera frugiperda. It is a publicly available structured database with insect pest sequences which will allow identification of a number of genes and comprehensive cloning of gene families of interest for scientific community. SPODOBASE is available from URL

Modélisation de la propagation d'une coupure sur stratifié mince de composite tissé soumis à un chargement cyclique de traction

National audienceCe papier présente un modèle de propagation de coupure (à travers l'épaisseur) sur matériau composite sous chargement de fatigue en traction. Il est adapté à un stratifié mince, de plis à renforts tissés, verre/époxy semblables a ceux utilisés pour les pales d'hélicoptère. La démarche adoptée vise à appréhender les phénomènes influençant la cinétique d'endommagement que l'on pourrait retrouver par exemple dans un revêtement de pale d'hélicoptère soumis à un effort longitudinal cyclique. Le modèle résultant, repose sur le principe original de découplage entre les comportements en fatigue des fibres et de la matrice. Il consiste en la superposition de deux maillages unidirectionnels représentant respectivement les fibres des directions chaîne et trame du stratifié, reliés par des éléments ressorts dont la raideur est dégradable. La méthode de modélisation ainsi que l'identification des paramètres du modèle est détaillée. Ce modèle a été éprouvé en comparant ses résultats aux vitesses de propagation de coupures sur des éprouvettes structurales représentatives de la structure d'un revêtement de pale présentant une entaille

A clinical trial combining megakaryocytes and haematopoietic stem cells to promote engraftment after autologous transplantation

International audienc

Negative regulation of transcription by the type II arginine methyltransferase PRMT5

We have identified previously a repressor element in the transcription start site region of the cyclin E1 promoter that periodically associates with an atypical, high molecular weight E2F complex, termed CERC. Purification of native CERC reveals the presence of the type II arginine methyltransferase PRMT5, which can mono- or symetrically dimethylate arginine residues in proteins. Chromatin immunoprecipitations (ChIPs) show that PRMT5 is associated specifically with the transcription start site region of the cyclin E1 promoter. ChIP analyses also show that this correlates with the presence on the same promoter region of arginine-methylated proteins including histone H4, an in vitro substrate of PRMT5. Consistent with its presence within the repressor complex, forced expression of PRMT5 negatively affects cyclin E1 promoter activity and cellular proliferation, effects that require its methyltransferase activity. These data provide the first direct experimental evidence that a type II arginine methylase is involved in the control of transcription and proliferation

PHENOPSIS Quelles évolutions technologiques du premier automate de phénotypage des plantes?

Afin de répondre aux besoins de phénotypage à haut débit dans le domaine végétal, le LEPSE (Laboratoire d’Ecophysiologie des plantes sous stress environnementaux) et la société Optimalog ont mis au point dès 2002 PHENOPSIS, un des premiers automates de phénotypage des plantes pour cultiver et suivre la croissance en pots de centaines de plantes de l’espèce modèle Arabidopsis thaliana et ce à des niveaux de déficit hydrique du sol contrôlés. Depuis, PHENOPSIS a été utilisé comme outil de phénotypage dans plusieurs dizaines de publications. En parallèle, l’outil a évolué à la demande des utilisateurs pour élargir la gamme de mesures phénotypiques, accroître la sécurité des utilisateurs et améliorer la traçabilité et la fiabilité des données. Cet article fait le point sur ces évolutions