Thyrotropin receptor antibodies in parotid saliva

Parotid saliva was collected with a Carlson-Crittenden device, under citric acid stimulation, in 18 patients with autoimmune thyroid disease. Thyrotropin Receptor Antibodies (TRAb) were measured with a radioreceptor assay in parotid saliva and in serum in the same patients, and a statistical analysis of the data was performed. TRAb levels in parotid saliva were higher than in serum in the 3 pathologies studied (Graves' disease, Hashitoxicosis and Hashimoto's thyroiditis). There was good correlation between salivary and serum levels.     

All-optical digital 4 × 2 encoder based on 2D photonic crystal ring resonators

The photonic crystals draw significant attention to build all-optical logic devices and are considered one of the solutions for the opto-electronic bottleneck via speed and size. The paper presents a novel optical 4 × 2 encoder based on 2D square lattice photonic crystals of silicon rods. The main realization of optical encoder is based on the photonic crystal ring resonator NOR gates. The proposed structure has four logic input ports, two output ports, and two bias input port. The photonic crystal structure has a square lattice of silicon rods with a refractive index of 3.39 in air. The structure has lattice constant ‘a’ equal to 630 nm and bandgap range from 0.32 to 044. The total size of the proposed 4 × 2 encoder is equal to 35 μm × 35 μm. The simulation results using the dimensional finite difference time domain and Plane Wave Expansion methods confirm the operation and the feasibility of the proposed optical encoder for ultrafast optical digital circuits.     

Strategic Information Systems: Current Research Issues

To ensure the maximum financial performance of organizations in rapidly changing environments, the coordination between strategic management objectives and information systems capabilities is of fundamental importance. This article proposes a conceptual framework for linking these 2 elements and suggests 10 hypotheses regarding this subject that merit further investigation by MIS managers.     

Isotropic and anisotropic dipeptide films based on gas phase deposition

We demonstrated the fabrication and application of well-ordered and vertically aligned dipeptide nanostructures based on a simple gas phase deposition. Deposited nanostructures exhibited the superhydrophobic property with a very low sliding angle. Highly reproducible SERS data have also been obtained after combining deposited films with a thin layer of gold. In addition to these, directional peptide films were, for the first time, successfully fabricated based on the oblique angle deposition technique. We believe that such bio-inspired materials would have a great impact in several technological applications involving catalysis, tissue engineering and biosensors.     

The tricriteria flowshop scheduling problem

Multicriteria flowshop scheduling problems have been one of the most attractive subjects in recent years. In the multicriteria flowshop scheduling literature, a very limited number of studies have been performed on problems which include a tardiness criterion. In this paper a multicriteria (tricriteria) two-machine flowshop scheduling problem with a tardiness criterion is tackled. The objective is to minimise a weighted sum of total completion time, total tardiness and makespan. An integer programming model is proposed for the problem which belongs to NP-hard class. The modified NEH (Nawaz, Enscore and Ham) algorithm, a tabu search-based heuristic method, random search and the EDD rule (the earliest due date rule) are used to solve problems with up to 2,500 jobs. A computational analysis is conducted to evaluate the performance of the heuristics. The analysis shows that the heuristics are quite efficient, and the performance of the tabu search based heuristic is the best of all in terms of solution quality.     

Microwave irradiated and thermally heated olive stone activated carbon for nickel adsorption from synthetic wastewater: A comparative study

In attempt to compare the removal efficiency and yield of the activated carbon prepared using the conventional and microwave‐assisted heating is the focus of this work. Toward this olive stone (a biomass precursor) is activated using the popular activating agent potassium hydroxide. The process optimization exercise is carried out by using the standard full factorial statistical design of experiments (response surface methodology). The activated carbons prepared under the optimized conditions are compared based on the adsorption capacity and yield. The adsorption capacity was found higher using microwave heating as compared with conventional heating. The microwave heating requires significantly lesser holding time as compared to conventional heating method to produce activated carbon of comparable quality, with higher yield. The BET surface area of carbon using microwave heating is significantly higher than the conventional heating. Although the mesopore surface area of carbon is not vary significantly, the activation time, power, and nitrogen gas consumption are significantly lower than the conventional heating rendering that the activation process via microwave is more economical than that via conventional heating. The adsorption isotherm data fitted the Langmuir isotherm well and the monolayer adsorption capacity was found to be 12.0 and 8.42 mg/g for microwave and thermally heated activated carbon, respectively. Regeneration studies showed that microwave‐irradiated and thermally heated olive stone could be used several times by desorption with an HCl reagent. Both carbons can be used for the efficient removal of Ni²⁺ (>99%) from contaminated wastewater. © 2013 American Institute of Chemical Engineers AIChE J, 60: 237–250, 2014     

Ultra-High bit rate all-optical AND/OR logic gates based on photonic crystal with multi-wavelength simultaneous operation

In this paper, a novel two-dimensional photonic crystal based all-optical AND/OR logic gates are designed, simulated and optimized. The structure is built on a linear square lattice photonic crystal platform. A multi-wavelength operation, together with a simultaneous operation, is achieved at ultra-high bit rates. The concurrent operation is attained without altering the proposed design continuously, as stated in the literature. It provides simplicity because there is no auxiliary input required along with the absence of externally attached phase shift units. The enhancement process has been done to the rod radius. A magnificent representation tool is developed. The benefit of the mentioned tool lies in the data combination of different operating wavelengths, contrast ratio, and bit rate; which will establish an efficient optimization process. Each gate is enhanced independently, then an overall improvement has been done. As a result, the operation at 1.52?µm will provide a successful multi logic gate operation with ultra-high bit rates of 6.76 and 4.74 Tbit/s for AND and OR logic gates, respectively. The design has an acceptable size of (19.8?×?12.6 µm) and a contrast ratio of 9.74?dB and 17.95?dB for the designed AND and OR gate, respectively. The design is highly sensitive to the waveguide length to verify the gates on demand.     

Radiation Synthesis and Magnetic Property Investigations of the Graft Copolymer Poly(Ethylene-g-Acrylic Acid)/Fe<Subscript>3</Subscript>O<Subscript>4</Subscript> Film

In this work, acrylic acid (AAc) monomer was grafted onto low-density polyethylene (LDPE) films by the direct method to obtain acid (LDPE-grafted poly(acrylic acid) (LDPE-g-PAAc)) graft copolymers. The presence of the grafted PAAc with COOH groups allows coupling with Fe^2+/3+ ions. The stabilization of Fe₃O₄ particles onto the graft copolymers was done by in situ reduction of LDPE-g-PAAc/Fe^2+/3+ with sodium borohydride (NaBH₄) in aqueous solution. The LDPE-g-PAAc graft copolymer and LDPE-g-PAAc/Fe₃O₄ composite films were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), and electron spin resonance (ESR). The synthesized composites exhibit excellent magnetic properties. The results indicated that the magnetic oxide (Fe₃O₄) was embedded and homogenously dispersed into the surfaces of the graft copolymer films as indicated by SEM. The FT-IR analysis clearly suggests that an AAc monomer was effectively grafted onto LDPE. The XRD studies elucidate the change in the crystallinity of the graft copolymers.

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Graphical Abstract The procedures for magnetic film manufacture LDPE-g-PAAc/Fe₃O₄ using gamma irradiation technique

     

A variational constitutive framework for the nonlinear viscoelastic response of a dielectric elastomer

We formulate a variational constitutive framework that accounts for nonlinear viscous behavior of electrically sensitive polymers, specifically Dielectric Elastomers (DEs), under large deformation. DEs are highly viscoelastic and their actuation response is greatly affected in dynamic applications. We used the generalized Maxwell model to represent the viscoelastic response of DE allowing the material to relax with multiple mechanisms. The constitutive updates at each load increment are obtained by minimizing an objective function formulated using the free energy and electrostatic energy of the elastomer, in addition to the viscous dissipation potential of the dashpots in each Maxwell branch. The model is then used to predict the electromechanical instability (EMI) of DE. The electro-elastic response of the DE is verified with available analytical solutions in the literature and then the material parameters are calibrated using experimental data. The model is integrated with finite element software to perform a variety of simulations on different types of electrically driven actuators under various electromechanical loadings. The electromechanical response of the DE and the critical conditions at which EMI occurs were found to be greatly affected by the viscoelasticity. Our model predicts that under a dead load EMI can be avoided if the DE operates at a high voltage rate. Subjected to constant, ramp and cyclic voltage, our model qualitatively predicts responses similar to the ones obtained from the analytical solutions and experimental data available in the literature.