Synthesis of 2-(2,3,4-trimethoxyphenyl)-1-(substituted-phenyl)acrylonitriles: in vitro anticancer activity against MCF-7, PC-3 and A2780 cancer cell lines

A series of 2-(2,3,4-trimethoxyphenyl)-1-(substituted-phenyl)acrylonitrile (2–9) were designed and synthesized to develop new cancer drugs. The structures of synthesized compounds 2–9 were described by using melting point, mass (MALDI-TOF-MS), FT-IR, elemental analysis, ¹H, ¹³C, ¹³C-APT and 2D NMR spectroscopy. The in vitro anticancer activities of 2–9 against human breast cancer (MCF-7), human prostate cancer (PC-3) and human ovarian cancer cells (A2780) were investigated by [3-(4,5-dimethylthiazol)-2-yl]-2,5-diphenyl-2H-tetrazolium bromide] (MTT) assay method. Additionally, the LogIC₅₀ values of these compounds on A2780, MCF-7 and PC-3 cell lines were calculated by using inhibition % values by the GraphPad Prism 6 program on a computer. The results indicated that these compounds have high anticancer activity against MCF-7, PC-3 and A2780 cell lines (especially A2780 cell lines, p < 0.05).     

Metal-dielectric-metal plasmonic waveguide devices for manipulating light at the nanoscale Invited Paper

We review some of the recent advances in the development of subwavelength plasmonic devices for ma- nipulating light at the nanoscale, drawing examples from our own work in metal-dielectric-metal (MDM) plasmonic waveguide devices. We introduce bends, splitters, and mode converters for MDM waveguides with no additional loss. We also demonstrate that optical gain provides a mechanism for on/off switch- ing in MDM plasmonie waveguides. Highly efficient compact couplers between dielectric waveguides and MDM waveguides are also introduced.     

Polyamide-imide/polyetherimide dual-layer hollow fiber membranes for pervaporation dehydration of C1–C4 alcohols

To circumvent the common swelling and deteriorated performance of integral asymmetric hollow fiber membranes for pervaporation dehydration, we have developed novel polyamide-imide (PAI)/polyetherimide (PEI) hollow fiber membranes with synergized performance with the aid of dual-layer spinning technology. Dehydration of C1–C4 alcohols has been conducted and the orders of their fluxes and permeances have been analyzed. The hollow fibers spun at 2 cm air gap and annealed at 75 °C exhibit the highest pervaporation performance: separation factors for t-butanol/water and iso-butanol/water binary systems are greater than 50,000 with flux more than 700 g/m² h. A comparison with literature data shows that the newly developed membranes outperform most other polymeric membranes for the dehydration of IPA and butanols. The dual-layer hollow fiber membranes also exhibit good long-term stability up to 200 h. The superior performance can be attributed to (1) the balanced properties of PAI as the selective layer for dehydration pervaporation; (2) the low water uptake and less swelling characteristic of the PEI supporting layer; and (3) the desirable membrane morphology consisting of a fully porous inner layer, a porous interface, and an ultrathin dense-selective outer skin.     

Deposition of MgF2 thin films for antireflection coating by using thermionic vacuum arc (TVA)

In this study, optical and surface properties of MgF₂ thin films produced by thermionic vacuum arc (TVA) technique have been investigated. By means of this technique the MgF₂ thin film produced by condensing the plasma of anode material generated by using TVA under high vacuum conditions on the glass. The optical properties have been investigated by using Filmetrics F20 and UV/VIS spectrometer. For surface properties of produced thin films EDS, SEM and AFM have been used. Our analysis shows that MgF₂ thin films produced by using TVA are proper single and multi layer anti-reflective (AR) coating and TVA technique brings very important advantages for ophthalmic glass coating and industrial applications' optical purposes.     

The preparation of primary mathematics teachers in Singapore: programs and outcomes from the TEDS-M study

This paper describes five aspects of primary mathematics teacher education in Singapore: (a) the teaching profession in Singapore, (b) the structure of pre-service teacher education programs offered by the National Institute of Education, (c) self-reports of Singapore future primary mathematics teachers about the opportunities to learn mathematics-related contents offered by these programs, based on the Teacher Education and Development Study in Mathematics (TEDS-M) survey, (d) the performance of these future teachers in mathematics content knowledge and mathematics pedagogical content knowledge assessed by the TEDS-M study, and (e) the relationships of opportunities to learn with this performance. The paper concludes with some suggestions about how to improve the quality of initial teacher preparation in the areas of recruitment and training.     

Double-step behavior of critical current vs. magnetic field in Y-, Bi- and Tl-based bulk high-Tc superconductors

A double step characteristic is observed at 76 K in the transport critical current as a function of magnetic field (10^-4 T to 10 T) in bulk sintered Y-, Bi- and Tl-based high-T_c superconducting materials. The low-field, step-like drop in the critical current density J_c commences at magnetic fields B between about 0.3 and 2 mT. This is followed by a plateau region of relatively constant critical current extending from about 30 to 300 mT, and then a second drop at fields between about 0.3 and 10 T. These features occur for all three superconductor materials and are interpreted respectively as a self-field/weak-link regime, a remnant percolation path regime and a flux-flow/upper-critical-field regime. The sharpness of the transition of the voltage-current (V-I characteristic, represented by the transition parameter n (i.e., V∝Iⁿ), has a similar double-step shape as a function of magnetic field directly corresponding to the features of the J_c(B) characteristic.     

Thermoanalytical studies of rubber oxidation catalyzed by metallic ions

The effects of several metallic ions on the oxidation of natural rubber were studied by differential scanning calorimetry (DSC). The activation energy of oxidation was evaluated from DSC curves. Cobalt, manganese, iron and copper ions decreased the activation energy of oxidation. Nickel, zinc and tin ions did not affect the activation energy. The effective ions are those which are able to undergo one-electron transfer redox reaction with hydroperoxide. Based on the activation energy values, the catalytic activities of metallic ions are: Co > Mn > Cu ? Fe > Ni ? Zn ? Sn.     

A numerical scheme for the solution of viscous Cahn–Hilliard equation

In this paper, we present a numerical scheme for the solution of viscous Cahn–Hilliard equation. The scheme is based on Adomian's decomposition approach and the solutions are calculated in the form of a convergent series with easily computable components. Some numerical examples are presented. © 2007 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2008