The viscoelastic behavior of a composite in a thermal environment

A proposed method for the accelerated predictions of modulus and life times for time dependent polymer matrix composite laminates is presented. The method, based on the time temperature superposition principle and lamination theory, is described in detail. Unidirectional reciprocal of compliance master curves and the shift functions needed are presented and discussed. Master curves for arbitrarily oriented unidirectional laminates are predicted and compared with experimantal results obtained from master curves generated from 15 minute tests and with 25 hour tests. Good agreement is shown. Predicted 30 deg and 60 deg unidirectional strength master curves are presented and compared to results of creep rupture tests. Reasonable agreement is demonstrated. In addition, creep rupture results for a (90 deg + or - 60 deg/90 deg) sub 2s laminate are presented

Compensated Row-Column Ultrasound Imaging System Using Fisher Tippett Multilayered Conditional Random Field Model

Ben Daya I, Chen AIH, Shafiee MJ, Wong A, Yeow JTW (2015) Compensated Row-Column Ultrasound Imaging System Using Fisher Tippett Multilayered Conditional Random Field Model. PLoS ONE 10(12): e0142817. doi:10.1371/journal.pone.01428173-D ultrasound imaging offers unique opportunities in the field of non destructive testing that cannot be easily found in A-mode and B-mode images. To acquire a 3-D ultrasound image without a mechanically moving transducer, a 2-D array can be used. The row column technique is preferred over a fully addressed 2-D array as it requires a significantly lower number of interconnections. Recent advances in 3-D row-column ultrasound imaging systems were largely focused on sensor design. However, these imaging systems face three intrinsic challenges that cannot be addressed by improving sensor design alone: speckle noise, sparsity of data in the imaged volume, and the spatially dependent point spread function of the imaging system. In this paper, we propose a compensated row-column ultrasound image reconstruction system using Fisher-Tippett multilayered conditional random field model. Tests carried out on both simulated and real row-column ultrasound images show the effectiveness of our proposed system as opposed to other published systems. Visual assessment of the results show our proposed system’s potential at preserving detail and reducing speckle. Quantitative analysis shows that our proposed system outperforms previously published systems when evaluated with metrics such as Peak Signal to Noise Ratio, Coefficient of Correlation, and Effective Number of Looks. These results show the potential of our proposed system as an effective tool for enhancing 3-D row-column imaging.This research was funded by the Natural Sciences and Engineering Research Council of Canada, the Canada Research Chairs Program, and the Ontario Ministry of Research and Innovation

Spectrum of Sizes for Perfect Deletion-Correcting Codes

One peculiarity with deletion-correcting codes is that perfect $t$-deletion-correcting codes of the same length over the same alphabet can have different numbers of codewords, because the balls of radius $t$ with respect to the Levenshte\u{\i}n distance may be of different sizes. There is interest, therefore, in determining all possible sizes of a perfect $t$-deletion-correcting code, given the length $n$ and the alphabet size~$q$. In this paper, we determine completely the spectrum of possible sizes for perfect $q$-ary 1-deletion-correcting codes of length three for all $q$, and perfect $q$-ary 2-deletion-correcting codes of length four for almost all $q$, leaving only a small finite number of cases in doubt.Comment: 23 page

In everlasting fight against academic procrastination: The roles of classroom engagement and internal locus of control

This study aims to test the hypothesis that classroom engagement mediates the relationship between students’ internal locus of control and academic procrastination. As many as 302 students from a private university between 18 to 26 years of age were recruited to respond to Internal-External Locus of control Scale, Classroom Engagement Inventory, and Academic Procrastination scale. Bootstrapping analyses were conducted by utilizing PROCESS Macro model 4 in SPSS software, and the results showed that the mediator variable fully mediates the link between the predictor and outcome variables. In other words, the direct effect of internal locus of control on academic procrastination was no longer significant when controlling for classroom engagement. Further discussion, implications and suggestions were presented at the end of the article

Generalized Brewster-Kerker effect in dielectric metasurfaces

Polarization is one of the key properties defining the state of light. It was discovered in the early 19th century by Brewster, among others, while studying light reflected from materials at different angles. These studies led to the first polarizers, based on Brewster's effect. One of the most active trends in photonics now is devoted to the study of miniaturized, sub-wavelength devices exhibiting similar, or even improved, functionalities compared to those achieved with bulk optical elements. In the present work, it is theoretically predicted that a properly designed all-dielectric metasurface exhibits a generalized Brewster effect potentially for any angle, wavelength and polarization of choice. The effect is experimentally demonstrated for an array of silicon nanodisks at visible wavelengths. The underlying physics of this effect can be understood in terms of the suppressed scattering at certain angles that results from the interference between the electric and magnetic dipole resonances excited in the nanoparticles, predicted by Kerker in early 80s. This reveals deep connection of Kerker's and Brewster's legacies and opens doors for Brewster phenomenon to new applications in photonics, which are not bonded to a specific polarization or angle of incidence.Comment: 12 pages, 5 figures, and supplementary information (22 pages

The birth of the Malaysian society for music in medicine: a concerted move to promote the use of music for therapeutic purposes

Malaysia is a multi-cultural society and the resulting myriad forms of music played in the nation are an ethnomusicologist’s haven. A simple cross-sample taken across the different kinds of music available reflects a diverse range reflective of much of the Asian region as a whole. Music medicine has existed for as long as the indigenous tribes have lived in the region. Formalized music therapy started in Malaysia approximately two decades ago by way of Western trained music therapists and is still in its infancy in therapeutic usage. As allopathic practitioners increasingly develop an evidence-based holistic mindset to complementary healing modalities, it is hoped that the use of music for therapeutic purposes will increase over time, and be localized for a population that blends Western, Chinese, Indian and indigenous healing systems. Efforts are made to conduct research using music-based intervention to provide evidence for integration of music medicine into Malaysian healthcare

Graphene-based material for microstrip bandpass filter

Graphene has become one of the most essential materials in recent years due to its numerous advantages and benefits. Because of its features, graphene is becoming more widespread in a variety of applications, particularly in electrical devices. In this research, graphene thick film paste (GTP) has been used to fabricate a microstrip bandpass filter (BPF). To obtain graphene nanoparticle powder, graphene oxide (GO) was synthesized from nanoparticle graphite using the Improved Hummers Method (IHM). The graphene oxide (GO) was chemically reduced to reduced graphene oxide or graphene (rGO) using ascorbic acid as the reducing agent. The structural and morphological properties of three nanoparticle powders, G, GO, and rGO, were investigated. An X-ray Diffractometer (XRD) (Rigaku Miniflex) with a diffraction angle of 10◦ to 60◦ was used to differentiate and determine the structure of crystalline materials. Thermal stability of the samples was identified using thermogravimetric analysis (TGA). The synthesized rGO has been used to fabricate BPF circuit. The obtained nanoparticle rGO was mixed with an organic carrier composed of linseed oil, m-xylene, and α-terpineol to form GTP. The GTP was screen printed on RT duroid 5880 substrates to form BPF circuit. The BPF circuit that was created was tested for paste-to-substrate adhesion. Then, the fabricated BPF circuit was tested using vector network analyzer (VNA) and compared with conventional BPF to obtain scattering parameter results which include return loss, insertion loss, and bandwidth. The graphene BPF circuit demonstrated a good performance with return loss and insertion loss at −27.481 dB and −0.725 dB, respectively, and a bandwidth of 1.5916 GHz while conventional return loss was −26.750 dB and insertion loss value the same as graphene which is −0.725 dB and bandwidth 0.7077 GHz. From the result graphene BPF showed better result than conventional BPF

The role of a digital engineering platform in appropriating the creation of new work-related mind-set and organisational discourse in a large multi-national company

YesThis paper reports on a case study involving a strategic and innovative approach to creation of an in-house multifaceted digital engineering platform (the DEP) in overcoming a number of organisational problems at a multinational engineering company. The DEP was to be used strategically for simplifying the operational complexity and to create and appropriate new work-related mind-set and new organisational discourse to achieve homogenous working across the organisation, which is a huge challenge. The need for this system emerged from the need to resolve many organisational services related problems that carried phenomenal amount of processes, health and safety risks and to regulate, and, control the running of engineering project. Research data were collected using a longitudinal case study approach over a period of six months. In order to make sense of how the DEP helped the organisation, the study used certain elements of Extended Structuration Theory as a lens to assess the case study. This research discovered that the DEP succeeded in creating and appropriating work-related mind-set and organisational discourse. It also had real influence on working processes and employees at all levels while encouraging transparency, responsiveness, agility and accountability. It continues to help the organisation to govern, manage and maintain good standard of service but many barriers still remain

Optimization of Naked DNA Delivery for Interferon Subtype Immunotherapy in Cytomegalovirus Infection

Type I interferon (IFN) gene therapy modulates the immune response leading to inflammatory heart disease following cytomegalovirus (CMV) infection in a murine model of post-viral myocarditis. Efficacy of different immunisation protocols for the IFN constructs was influenced by the dose of DNA, subtype choice, combination use, pre-medication, and timing of DNA administration. Optimal efficacy was found with bupivacaine treatment prior to DNA inoculation of 200mg IFN DNA 14 days prior to virus challenge. Maximal antiviral and antimyocarditic effects were achieved with this vaccination schedule. Furthermore, inoculation of synergistic IFN subtypes demonstrated enhanced efficacy when delivered either alone or with CMV gB DNA vaccination in the CMV model. Thus naked DNA delivery of IFN provides an avenue of immunotherapy for regulating herpesvirus-induced diseases

Controlled assembly of SNAP-PNA-fluorophore systems on DNA templates to produce fluorescence resonance energy transfer

The SNAP protein is a widely used self-labeling tag that can be used for tracking protein localization and trafficking in living systems. A model system providing controlled alignment of SNAP-tag units can provide a new way to study clustering of fusion proteins. In this work, fluorescent SNAP-PNA conjugates were controllably assembled on DNA frameworks forming dimers, trimers, and tetramers. Modification of peptide nucleic acid (PNA) with the O6-benzyl guanine (BG) group allowed the generation of site-selective covalent links between PNA and the SNAP protein. The modified BG-PNAs were labeled with fluorescent Atto dyes and subsequently chemo-selectively conjugated to SNAP protein. Efficient assembly into dimer and oligomer forms was verified via size exclusion chromatography (SEC), electrophoresis (SDS-PAGE), and fluorescence spectroscopy. DNA directed assembly of homo- and hetero-dimers of SNAP-PNA constructs induced homo- and hetero-FRET, respectively. Longer DNA scaffolds controllably aligned similar fluorescent SNAP-PNA constructs into higher oligomers exhibiting homo-FRET. The combined SEC and homo-FRET studies indicated the 1:1 and saturated assemblies of SNAP-PNA-fluorophore:DNA formed preferentially in this system. This suggested a kinetic/stoichiometric model of assembly rather than binomially distributed products. These BG-PNA-fluorophore building blocks allow facile introduction of fluorophores and/or assembly directing moieties onto any protein containing SNAP. Template directed assembly of PNA modified SNAP proteins may be used to investigate clustering behavior both with and without fluorescent labels which may find use in the study of assembly processes in cells