Effectiveness of Taguchi method for the optimization of narrowband optical filters based on grating waveguides

Microsystem Technologies - This work is an illustration of a narrowband optical filter device based on cladding modulated grating waveguide for enhancing the device performance in terms of...     

LiFi up-downlink conversion node model generated by inline successive optical pumping

Microsystem Technologies - An on-chip-scale, up-down link conversion circuit for electro-optic signals to use in a light fidelity network application is proposed. A system consisting of a loop...     

Exploring a reversible NOR from a 4 × 4 modified Fredkin gate and its optical mapping using a LiNbO3-based MZI

Journal of Computational Electronics - The extensive search for the implementation of reversible logic using emerging technologies has paved the way for the rise of optical computing. The...     

Design and fabrication of a new high gain multilayer negative refractive index metamaterial antenna for X‐band applications

This article presents the design of a planar high gain and wideband antenna using a negative refractive index multilayer superstrate in the X‐band. This meta‐antenna is composed of a four‐layer superstrate placed on a conventional patch antenna. The structure resonates at a frequency of 9.4 GHz. Each layer of the metamaterial superstrate consists of a 7 × 7 array of electric‐field‐coupled resonators, with a negative refractive index of 8.66 to 11.83 GHz. The number of layers and the separation of superstrate layers are simulated and optimized. This metamaterial lens has significantly increased the gain of the patch antenna to 17.1 dBi. Measurements and simulation results proved about 10 dB improvement of the gain.     

Daily Mean Streamflow Prediction in Perennial and Non-Perennial Rivers Using Four Data Driven Techniques

This study examines and compares the performance of four new attractive artificial intelligence techniques including artificial neural network (ANN), hybrid wavelet-artificial neural network (WANN), Genetic expression programming (GEP), and hybrid wavelet-genetic expression programming (WGEP) for daily mean streamflow prediction of perennial and non-perennial rivers located in semi-arid region of Zagros mountains in Iran. For this purpose, data of daily mean streamflow of the Behesht-Abad (perennial) and Joneghan (non-perennial) rivers as well as precipitation information of 17 meteorological stations for the period 1999–2008 were used. Coefficient of determination (R²) and root mean square error (RMSE) were used for evaluating the applicability of developed models. This study showed that although the GEP model was the most accurate in predicting peak flows, but in overall among the four mentioned models in both perennial and non-perennial rivers, WANN had the best performance. Among input patterns, flow based and coupled precipitation-flow based patterns with negligible difference to each other were determined to be the best patterns. Also this study confirmed that combining wavelet method with ANN and GEP and developing WANN and WGEP methods results in improving the performance of ANN and GEP models.     

A grasshopper optimizer approach for feature selection and optimizing SVM parameters utilizing real biomedical data sets

Neural Computing and Applications - Support vector machines (SVM) are one of the important techniques used to solve classifications problems efficiently. Setting support vector machine kernel...     

Effects of mixing strategy on catalyst‐assisted reactive blending of polycarbonate and polyethylene terephthalate

Reactive melt mixing of polycarbonate (PC) and polyethylene terephthalate (PET) blends with constant composition of 80:20 in the presence of a freshly added catalyst was conducted through a two‐step method. At first, PC and PET underwent premixing and melt mixed in the absence of a fresh catalyst. Then, mixing continued with catalyst addition under the same previous condition. The effects of varied premixing times from 1 to 5 min and mixing intensity at rotor speeds of 30 and 50 rev/min (rpm) were separately evaluated in transesterification reaction. The results of solubility analysis showed that the longer premixing time and the higher mixing rate enhanced the rate and extension of reaction. Fourier transform infrared (FTIR) spectroscopy and thermal analysis by differential scanning calorimetry were conducted on specimens on the basis of solubility separations. The height ratio of carbonyl group peaks of PC and PET phases were calculated for their corresponding FTIR spectra. The height ratio for PET showed a good correlation with solubility data. Moreover, crystallinity of PET phase was influenced by the reaction which was analyzed by solubility parameters. J. VINYL ADDIT. TECHNOL., 25:127–133, 2019. © 2018 Society of Plastics Engineers     

Detection of ROS and translocation of ERP-57 in apoptotic induced human neuroblastoma (SH-SY5Y) cells

Several toxic compounds are known to induce apoptosis in mammalian cell lines. The human neuroblastoma cells (SH-SY5Y) were exposed to the phosphatase inhibiting toxin okadaic acid (OA) or hydrogen peroxide (H2O2) to induce apoptosis as well as generate reactive oxygen species (ROS). Mitoxantrone (MXT) was used as a positive control for apoptosis. The SH-SY5Y cells were transfected with eukaryotic expression plasmid pHyPer-dMito encoding mitochondrial-targeted fluorescent or pHyPer-dCito encoding cytoplasmic-targeted fluorescent sensor for hydrogen peroxide (HyPer). The ERp57, also called GRP58 (Glucose-regulated protein 58), is a stress protein induced in conditions like glucose starvation and viral infection. Recently ERp57 was shown to translocate from the endoplasmatic reticulum to the cell surface in anthracycline-induced apoptotic cells. ERp57 co-translocation together with calreticulin has been suggested to be crucial for recognizing tumor cells to induce immunogenic cell death. ERp57 translocation after exposure to okadaic acid was studied using immunofluorescence and confocal microscopy. These studies indicated that okadaic acid has induced the translocation of ERp57 to the cellular membrane.     

On the encapsulation of natural pesticide using polyvinyl alcohol/alginate–montmorillonite nanocomposite for controlled release application

A representative pesticide, NeemAzal was encapsulated into polyvinyl alcohol/alginate‐montmorillonite (PVA/Alg‐MMT) nanocomposite by cross‐linking with glutaraldehyde. Different formulations of capsule beads containing NeemAzal were prepared with different concentration of materials. Evidence of cross‐linking of PVA and Alg was obtained by comparison of the Fourier transform infrared spectra of the initial substrates and capsule beads. X‐ray diffraction and transmission electron microscopy techniques confirmed the intercalated structure of capsule bead nanocomposites. In addition the swelling behavior of capsule beads was investigated. Results showed that swelling ratio of capsule beads decreases with introduction of MMT as well as increase of PVA content in capsule bead formulations. The release characteristics of NeemAzal from capsule beads were monitored using UV–visible spectrophotometer in distilled water. The addition of sodium MMT to these formulations was found to have a profound inhibitory effect on the release of NeemAzal. Furthermore, the release data were fitted to several empirical equations to estimate the kinetic parameters. The NeemAzal encapsulated PVA/Alg‐MMT nanocomposite capsule beads, designed and discussed in this work, have the potential for controlled release of pesticide. POLYM. ENG. SCI., 54:2707–2714, 2014. © 2013 Society of Plastics Engineers     

Effect of electron beam irradiation dose on the rheology,morphology, and thermal properties of branched polypropylene/polybutene‐1 blend

The aim of this work is to study the influence of electron beam irradiation on the structure of polypropylene (PP)/polybutene‐1 (PB‐1) blend in the branching process. The blend with 10 wt% of PB‐1 and 0.5 wt% trimethylolpropane trimethacrylate monomer is prepared and irradiated at different doses. The rheological properties of the melts in shear and extensional mode were evaluated, and their thermal behavior, crystalline structure, and morphology are studied by differential scanning calorimetry, wide‐angle X‐ray diffraction, and scanning electron microscopy. The presence of long chain branched structure is approved by higher zero‐shear viscosity (η₀), longer relaxation time and pronounced strain‐hardening behavior in the within the range of dose tested. By increasing the irradiation dose and enhancing chain scission in the backbone and long chain branches, the decline in melting temperature, duplication of melting peak, and the decrease in zero‐shear viscosity were observed. The morphological study of the blends before and after irradiation revealed no considerable change in PB‐1 droplet size and their distribution in the PP matrix. The emulsion theoretical models could predict well the rheological behavior of all samples and no significant change was observed on the interfacial interaction of PP and PB‐1. POLYM. ENG. SCI., 54:1747–1756, 2014. © 2013 Society of Plastics Engineers