FlyAtlas: database of gene expression in the tissues of drosophila melanogaster

The FlyAtlas resource contains data on the expression of the genes of Drosophila melanogaster in different tissues (currently 25—17 adult and 8 larval) obtained by hybridization of messenger RNA to Affymetrix Drosophila Genome 2 microarrays. The microarray probe sets cover 13 250 Drosophila genes, detecting 12 533 in an unambiguous manner. The data underlying the original web application (http://flyatlas.org) have been restructured into a relational database and a Java servlet written to provide a new web interface, FlyAtlas 2 (http://flyatlas.gla.ac.uk/), which allows several additional queries. Users can retrieve data for individual genes or for groups of genes belonging to the same or related ontological categories. Assistance in selecting valid search terms is provided by an Ajax ‘autosuggest’ facility that polls the database as the user types. Searches can also focus on particular tissues, and data can be retrieved for the most highly expressed genes, for genes of a particular category with above-average expression or for genes with the greatest difference in expression between the larval and adult stages. A novel facility allows the database to be queried with a specific gene to find other genes with a similar pattern of expression across the different tissues

Modification of Cu nanoparticles with a disulfide for polyimide metallization

Copper metallization on polyimide films was carried out via a wet chemical process. This process included the chemical reaction of KOH with PI to form poly(amic acid) (PAA), ion exchange of doped K(+) with Cu(2+) to form Cu(2+)-doped PAA, doped Cu(2+) reduction by aqueous dimethylamine borane (DMAB) to form copper nanoparticles (CNPs) on PAA, and electroless copper (ELC) deposition catalyzed by CNPs on PAA. An organic additive, namely, bis(3-sulfopropyl)-disulfide (SPS), that can effectively reduce the size of CNPs and significantly enhance the chemical activity of CNPs for ELC deposition was used in this work. For comparison, doped Cu(2+) ions in the PAA were also reduced by hydrogen gas at 350 degrees C. The results show that only aqueous reductants can induce the reduced copper atoms to aggregate on the PAA surface and to form a granular copper layer that acts as a catalyst for the ELC deposition. Mechanisms for the aggregation of copper atoms and for activity enhancement of the CNPs due to SPS addition in the DMAB solution are proposed according to the evidence obtained from Fourier transform infrared spectrometry (FTIR), X-ray photoelectron spectrometry (XPS), field emission scanning electron microscopy (FESEM), cross-sectional transmission electron microscopy (TEM), and atomic force microscopy (AFM). The CNP-coated PAA films and the structures of the ELC deposits were characterized by X-ray diffraction (XRD) and UV-visible spectrophotometry (UV-Vis), respectively

Multiscale approach for three-phase CNT/polymer/fiber laminated nanocomposite structures

The free vibration analysis of laminated nanocomposite plates and shells using first-order shear deformation theory and the Generalized Differential Quadrature (GDQ) method is presented. Each layer of the laminate is modelled as a three-phase composite. An example of such composite material is given by a polymeric matrix reinforced with Carbon Nanotubes (CNTs). CNTs enhance the mechanical properties of the polymer matrix and the nanocomposite is treated as an isotropic material; a micromechanics model is used to compute the engineering constants of the isotropic hybrid material. This approach based on the Eshelby-Mori-Tanaka scheme takes into account the agglomeration of the nanoparticles in the matrix. The second step consists in combining this enriched matrix with unidirectional and oriented reinforcing fibers to obtain a fibrous composite with improved mechanical features. The overall mechanical properties of each orthotropic ply are evaluated through different micromechanics approaches. Each technique is illustrated in details and the transversely isotropic properties of the three-phase layers are completely defined. The effects of both CNTs agglomeration and the mass fraction of these particles are investigated comparing with the results obtained by various homogenization techniques

Transient Depletion of Kupffer Cells Leads to Enhanced Transgene Expression in Rat Liver Following Retrograde Intrabiliary Infusion of Plasmid DNA and DNA Nanoparticles

In this report, we have demonstrated that by temporarily removing Kupffer cells (KCs), the transgene expression levels mediated by retrograde intrabiliary infusion (RII) of plasmid DNA, polyethylenimine-DNA, and chitosan nanoparticles were enhanced by 1,927-, 131-, and 23,450-fold, respectively, in comparison with the respective groups without KC removal. KC removal also led to significantly prolonged transgene expression in the liver that received all three carriers. This increased transgene expression was correlated with significantly reduced serum tumor necrosis factor-α level as an indicator for KC activation. These results suggest that KC activation is a significant contributing factor to the lowered transgene expression by polycation-DNA nanoparticles delivered by RII. More importantly, the combination of RII and transient removal of KCs may be adopted as an effective approach to achieving high and persistent transgene expression in the liver mediated by nonviral nanoparticles

Fabrication, testing and analysis of steel/composite DLS adhesive joints

This paper describes experimental and numerical techniques to study the structural design of double lap shear joints that are based on thick-adherend steel/steel and steel/composite, with epoxy adhesive. A standard practical fabrication method was used to produce specimens of various dimensions and materials. These specimens consist of 10 mm steel inner adherend and various outer adherend materials including composite and steel of various thicknesses and overlaps. The composite is largely based on carbon fibre reinforced plastic. The specimens were tested under monotonic tensile loading and the results showed that joint strength depends largely on materials combination and overlap length. The testing also included the use of an advanced imaging system to determine failure initiation and propagation. Two-dimensional finite element analysis (FEA) stress models were applied and showed the importance of modelling the composite layers adjacent to the adhesive bondline in order to account for the critical local stresses. The FEA results also showed that overall shear stress distributions can be used to characterise joint failure. The paper presents the experimental and numerical details with key conclusions