Thermal Inspection of a Composite Fuselage Section Using a Fixed Eigenvector Principal Component Analysis Method

A composite fuselage aircraft forward section was inspected with flash thermography. The fuselage section is 24 feet long and approximately 8 feet in diameter. The structure is primarily configured with a composite sandwich structure of carbon fiber face sheets with a Nomex(Trademark) honeycomb core. The outer surface area was inspected. The thermal data consisted of 477 data sets totaling in size of over 227 Gigabytes. Principal component analysis (PCA) was used to process the data sets for substructure and defect detection. A fixed eigenvector approach using a global covariance matrix was used and compared to a varying eigenvector approach. The fixed eigenvector approach was demonstrated to be a practical analysis method for the detection and interpretation of various defects such as paint thickness variation, possible water intrusion damage, and delamination damage. In addition, inspection considerations are discussed including coordinate system layout, manipulation of the fuselage section, and the manual scanning technique used for full coverage

PDE-4 inhibition rescues aberrant synaptic plasticity in Drosophila and mouse models of fragile X syndrome.

Fragile X syndrome (FXS) is the leading cause of both intellectual disability and autism resulting from a single gene mutation. Previously, we characterized cognitive impairments and brain structural defects in a Drosophila model of FXS and demonstrated that these impairments were rescued by treatment with metabotropic glutamate receptor (mGluR) antagonists or lithium. A well-documented biochemical defect observed in fly and mouse FXS models and FXS patients is low cAMP levels. cAMP levels can be regulated by mGluR signaling. Herein, we demonstrate PDE-4 inhibition as a therapeutic strategy to ameliorate memory impairments and brain structural defects in the Drosophila model of fragile X. Furthermore, we examine the effects of PDE-4 inhibition by pharmacologic treatment in the fragile X mouse model. We demonstrate that acute inhibition of PDE-4 by pharmacologic treatment in hippocampal slices rescues the enhanced mGluR-dependent LTD phenotype observed in FXS mice. Additionally, we find that chronic treatment of FXS model mice, in adulthood, also restores the level of mGluR-dependent LTD to that observed in wild-type animals. Translating the findings of successful pharmacologic intervention from the Drosophila model into the mouse model of FXS is an important advance, in that this identifies and validates PDE-4 inhibition as potential therapeutic intervention for the treatment of individuals afflicted with FXS

Banana fiber-LDPE recycled composites for low-cost eco-friendly construction applications

Currently, McGill is collaborating with University of Western Australia, Moratuwa Univeristy (Colombo, Sri Lanka), and Waste for Life to create affordable eco-friendly building products for Sri Lanka. By using recycled LDPE waste plastics as well as banana fibers made from waste banana trees, composites can be made for basic housing applications. The composite material is to be made using methods easily reproducible in Sri Lanka at a low cost. Tensile properties, flame retardancy and moisture absorption were investigated to create a strong, safe, and durable product. First the plastic matrix (from Sri Lankan and Canadian sources) and banana fiber reinforcement were characterized using differential scanning calorimetry, thermogravimetric analysis, and Fourier-transform infrared spectroscopy. This is to ensure that the processing parameters can be generalized to both countries. Then a manufacturing method using compression molding was developed. Fibers of different length were used to assess their effect on manufacturing and strength. Panels made with 40 wt% of 20 cm long fibers in a random orientation yielded the best results. Then, UL94 fire tests were conducted with ATH mineral filler as a flame retardant. Integrating the flame retardant directly into the composite's layers is the most efficient way of reducing flame spread. Then, different commercially available waterproofing solutions were used to prevent moisture absorption into the composite panels. Sealing the composite with an outer layer of at least 0.3 mm of LDPE was the cheapest and most effective way to prevent water intrusions. Finally, the three aspects of the project (tensile strength, fireproofing, water absorption) were combined in a final product and characterized.En collaboration avec l'Université McGill, l'University of Western Australia, Moratuwa University, et l'organisme Waste For Life, ce présent projet avait pour but de concevoir des matériaux de construction en composite à partir de plastiques recyclés et de fibres naturelles. Pour ce faire, il était essentiel de tenir compte du contexte particulier de l'étude, soit les communautés du Sri Lanka, en n'utilisant que des procédés abordables et consciencieux de l'environnement.En utilisant les déchets de plastique polyéthylène à basse densité (PEBD) ainsi que des fibres naturelles provenant des déchets agricoles de bananiers, des matériaux composites peuvent alors être créés. Un procédé de fabrication facilement reproductible au Sri Lanka doit être conçu, et ce, à faible coût. Les propriétés de traction, l'amélioration de propriétés ignifuges, et l'absorption d'humidité furent étudiés afin de créer un matériau fort, sécuritaire et durable. Tout d'abord, la matrice thermoplastique (de sources sri lankaises et canadiennes) et le renfort de fibres de bananes furent caractérisés par calorimétrie différentielle à balayage, analyse thermogravimétrique et spectroscopie infrarouge à transformée de Fourier. Cette étape permettra de déterminer les paramètres de fabrications et si ceux-ci pourront être applicables au Sri Lanka. Ensuite, un procédé de fabrication usant le moulage à compression fût développé. Des fibres coupées de différentes longueurs furent utilisées afin d'évaluer leurs effets sur les propriétés mécaniques et la vitesse de fabrication. Par ailleurs, l'usage de fibres de 20 cm sans orientations prédéterminées/fixes avec une charge de 40% par poids ont fournis les meilleurs résultats. Par la suite, des tests de feux suivant le standard UL94 furent effectués avec la présence d'hydroxyde d'aluminium, soit un retardant à flamme. À cet effet, l'addition du retardant à flamme directement entre les couches du matériau composite s'avère la méthode la plus efficace pour ralentir la propagation des flammes. Enfin, pour améliorer l'imperméabilité du composite, différents scellants commerciaux furent utilisés. D'ailleurs, l'addition d'une couche protectrice de PEBD de 0.3 mm fut la méthode la plus économique et efficace pour assurer l'étanchéité du matériau. Finalement, les trois aspects du projets (propriétés des tractions, feu, et absorption d'humidité) furent intégrés pour créer un produit final

PDE-4 Inhibition Rescues Aberrant Synaptic Plasticity in Drosophila and Mouse Models of Fragile X Syndrome

Fragile X syndrome (FXS) is the leading cause of both intellectual disability and autism resulting from a single gene mutation. Previously, we characterized cognitive impairments and brain structural defects in a Drosophila model of FXS and demonstrated that these impairments were rescued by treatment with metabotropic glutamate receptor (mGluR) antagonists or lithium. A well-documented biochemical defect observed in fly and mouse FXS models and FXS patients is low cAMP levels. cAMP levels can be regulated by mGluR signaling. Herein, we demonstrate PDE-4 inhibition as a therapeutic strategy to ameliorate memory impairments and brain structural defects in the Drosophila model of fragile X. Furthermore, we examine the effects of PDE-4 inhibition by pharmacologic treatment in the fragile X mouse model. We demonstrate that acute inhibition of PDE-4 by pharmacologic treatment in hippocampal slices rescues the enhanced mGluR-dependent LTD phenotype observed in FXS mice. Additionally, we find that chronic treatment of FXS model mice, in adulthood, also restores the level of mGluR-dependent LTD to that observed in wild-type animals. Translating the findings of successful pharmacologic intervention from the Drosophila model into the mouse model of FXS is an important advance, in that this identifies and validates PDE-4 inhibition as potential therapeutic intervention for the treatment of individuals afflicted with FXS

IMG/VR: a database of cultured and uncultured DNA Viruses and retroviruses

Viruses represent the most abundant life forms on the planet. Recent experimental and computational improvements have led to a dramatic increase in the number of viral genome sequences identified primarily from metagenomic samples. As a result of the expanding catalog of metagenomic viral sequences, there exists a need for a comprehensive computational platform integrating all these sequences with associated metadata and analytical tools. Here we present IMG/VR (https://img.jgi.doe.gov/vr/), the largest publicly available database of 3908 isolate reference DNA viruses with 264 413 computationally identified viral contigs from >6000 ecologically diverse metagenomic samples. Approximately half of the viral contigs are grouped into genetically distinct quasi-species clusters. Microbial hosts are predicted for 20 000 viral sequences, revealing nine microbial phyla previously unreported to be infected by viruses. Viral sequences can be queried using a variety of associated metadata, including habitat type and geographic location of the samples, or taxonomic classification according to hallmark viral genes. IMG/VR has a user-friendly interface that allows users to interrogate all integrated data and interact by comparing with external sequences, thus serving as an essential resource in the viral genomics community