A simple equivalent plate model for dynamic bending stiffness of three-layer sandwich panels with shearing core

Equivalent or condensed plate models are being used in various industries to reduce the computation time in finite element modelling. Out of the available equivalent plate models, the model developed by J.L.Guyader in 1978 exhibits high agreement with Lamb wave theory but it requires some time for implementation. Therefore, in this paper, a simple model is proposed to quickly compute the dynamic equivalent parameters of a three-layer sandwich panel. Although the model is formulated from only four parameters, which could be easily computed via the asymptotic and transition behaviours of the sandwich panel, it is shown to be able to capture the equivalent dynamic response for the entire frequency range

Thymidine Kinase 2 Deficiency-Induced Mitochondrial DNA Depletion Causes Abnormal Development of Adipose Tissues and Adipokine Levels in Mice

Mammal adipose tissues require mitochondrial activity for proper development and differentiation. The components of the mitochondrial respiratory chain/oxidative phosphorylation system (OXPHOS) are encoded by both mitochondrial and nuclear genomes. The maintenance of mitochondrial DNA (mtDNA) is a key element for a functional mitochondrial oxidative activity in mammalian cells. To ascertain the role of mtDNA levels in adipose tissue, we have analyzed the alterations in white (WAT) and brown (BAT) adipose tissues in thymidine kinase 2 (Tk2) H126N knockin mice, a model of TK2 deficiency-induced mtDNA depletion. We observed respectively severe and moderate mtDNA depletion in TK2-deficient BAT and WAT, showing both tissues moderate hypotrophy and reduced fat accumulation. Electron microscopy revealed altered mitochondrial morphology in brown but not in white adipocytes from TK2-deficient mice. Although significant reduction in mtDNA-encoded transcripts was observed both in WAT and BAT, protein levels from distinct OXPHOS complexes were significantly reduced only in TK2-deficient BAT. Accordingly, the activity of cytochrome c oxidase was significantly lowered only in BAT from TK2-deficient mice. The analysis of transcripts encoding up to fourteen components of specific adipose tissue functions revealed that, in both TK2-deficient WAT and BAT, there was a consistent reduction of thermogenesis related gene expression and a severe reduction in leptin mRNA. Reduced levels of resistin mRNA were found in BAT from TK2-deficient mice. Analysis of serum indicated a dramatic reduction in circulating levels of leptin and resistin. In summary, our present study establishes that mtDNA depletion leads to a moderate impairment in mitochondrial respiratory function, especially in BAT, causes substantial alterations in WAT and BAT development, and has a profound impact in the endocrine properties of adipose tissues

Infliximab: 12 years of experience

Rheumatoid arthritis (RA), ankylosing spondylitis (AS) and psoriatic arthritis (PsA) are immune-mediated conditions that share an inflammatory mechanism fuelled by excessive cytokines, particularly TNF. Control of inflammation and rapid suppression of cytokines are important in treating these diseases. With this understanding and the corresponding advent of TNF inhibitors, RA patients, AS patients and PsA patients have found more choices than ever before and have greater hope of sustained relief. As a widely used TNF inhibitor, infliximab has a deep and established record of efficacy and safety data. Extensive evidence - from randomised controlled clinical trials, large registries and postmarketing surveillance studies - shows that infliximab effectively treats the signs and symptoms, provides rapid and prolonged suppression of inflammation, prevents radiologically observable disease progression and offers an acceptable safety profile in RA, AS and PsA. In very recent studies, investigators have observed drug-free remission in some patients. Additionally, infliximab may interfere with rapidly progressing disease in RA by early addition to methotrexate in patients with signs of an aggressive course. Finally, infliximab has been shown to reduce PsA clinical manifestations such as nail involvement. With our current understanding, substantial data and increasing confidence regarding use in practice, infliximab can be considered a well-known drug in our continued campaign against inflammatory rheumatic diseases

A direct link between microstructure and acoustical macro-behavior of real double porosity foams

Copyright 2013 Acoustical Society of America. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the Acoustical Society of America. The following article appeared in the Journal of the Acoustical Society of America (JASA) and may be found at http://link.aip.org/link/?JAS/134/4681.International audienceThe acoustical macro-behavior of mineral open-cell foam samples is modelled from microstructure morphology using a three-dimensional idealized periodic unit-cell (3D-PUC). The 3D-PUC is based on a regular arrangement of spheres, allowed to interpenetrate during the foaming process. Identi cation and sizing of the 3D-PUC is made from X-ray computed microtomography and manufacturing process information. In addition, the 3D-PUC used allows to account for two scales of porosity: the interconnected network of bubbles (meso-porosity) and the inter-crystalline porosity of a gypsum matrix (micro-porosity). Transport properties of the micro- and the meso- scales are calculated from fi rst principles and a hybrid micro-macro method is used in order to determine the frequency-dependent visco-thermal dissipation properties. The double porosity theory provides the visco-thermal coupling between the meso- and micro- scales [J. Acoust. Soc. Am. 114, 7389 (2003)]. Finally, the results are successfully compared with experiments for two di erent mineral foam samples. The main originality of this work is to maintain a direct link between the microstructure morphology and the acoustical macro-behavior all along the multi-scale modelling process, without any adjusted parameter

Mise a jour taxonomique et nomenclaturale des asteraceae du Togo

La flore du Togo éditée depuis 1984 n’a suivi à ce jour aucune mise à jour mais depuis lors, de nouvelles investigations et récoltes lui ont été ajoutées. L’actualisation de cette flore passe par la mise à jour nomenclaturale et taxonomique des spécimens d’herbier du Togo. L’objectif de cette étude est de mettre à jour la liste des Asteraceae du Togo à travers les échantillons d’herbier. Ce travail s’inscrit dans celui plus global de réaliser une mise à jour taxonomique et nomenclaturale de la flore du Togo. Cette mise à jour actuellement est facilitée par l’informatisation de l’herbier et de l’exploitation de sa base de données qui est le RIHA (Réseau Informatique des Herbiers d’Afrique). Le matériel utilisé relève des étiquettes d’herbier et de la base de données RIHA de l’Herbier de l’Université de Lomé. Plusieurs extraits issus des requêtes ont permis de dresser les listes des Asteraceae du Togo. Une comparaison avec la flore du Togo a permis de confirmer ladite liste. La consultation de plusieurs bases de données botaniques ont permis de faire le parallèle entre les noms d’étiquettes et les noms valides en cours d’usage actuellement. Les résultats montrent que la flore du Togo est riche de 110 espèces réparties en 48 genres. Sur le nombre total d’espèces, 31 espèces portent encore sur les étiquettes, des noms invalides. Les usages relevés sur les étiquettes sont d’ordre médicinal et alimentaire. Mots clés: Flore du Togo, mise à jour, Asteraceae, base de données, RIHA English Title: Taxonomic and nomenclatural revision of asteraceae of Togo  English Abstract The flora of Togo published since 1984 has not been updated to date but since then, new investigations and harvests have been added. The updating of this flora requires the nomenclatural and taxonomic updating of the herbarium specimens. The objective of this study is to update the list of Asteraceae of Togo through herbarium sheets. This work is part of the more global task of carrying out a taxonomic and nomenclatural update of the Togo’s flora. This updating is currently facilitated by the computerization of the herbarium and the exploitation of its database which is the RIHA (Réseau Informatique des Herbiers d'Afrique). The equipment used is from the herbarium labels and the RIHA database of the Herbarium of the University of Lomé. Several extracts from the queries made it possible to draw up lists of Asteraceae from Togo. A comparison with the flora of Togo made it possible to confirm the said list. Consultation of several  botanical databases made it possible to draw a parallel between the label names and the valid names currently in use. The results show that the flora of Togo is rich with 110 species of Asteraceae divided into 48 genera. Out of the total number of species, 31 species still have invalid names on labels. The uses noted on the labels are medicinal and food uses. Keywords: Togo's Flora, updating, Asteraceae family, computerizatio