Network Architecture and Wireless Ad Hoc Routing for Airborne Internet Services

Wireless Personal Communications - The passengers traveling in aircraft require access to the internet to effectively utilizing their precious in-flight time. Providing internet services to such...     

Regioselective O-alkylation: synthesis of 1-{2-[(2-chloroquinolin-3-yl)methoxy]-6-chloro-4-phenylquinolin-3-yl}ethanones

An efficient and regioselective O-alkylation of amides with a variety of electrophiles in the presence of silver nanoparticles is reported as part of our recent research on building blocks for synthesis of natural products. The nano-silver catalyst initiates O-alkylation of the amides by heteroalkyl halides. Reaction of equimolar 3-acetyl-6-chloro-4-phenylquinolin-2(1H)-one and 2-chloro-3-(chloromethyl)quinolines in the presence of silver nanoparticles in DMSO solution under reflux condition leads to the formation of 1-{1-[2-chloroquinolin-3-yl)methoxy]-6-chloro-4-phenylquinolin-3-yl}ethanones.     

In vitro study of cell death with 5-aminolevulinic acid based photodynamic therapy to improve the efficiency of cancer treatment

Photodynamic therapy (PDT) is a kind of photochemo therapeutic treatment that exerts its effect mainly through the induction of cell death. Distinct types of cell death may be elicited by different PDT regimes. In this study, efforts are underway to optimize PDT protocols for improved efficacy and combination of all three PDT mechanisms involved in the different human carcinomas cell narcosis. Our in vitro cell culture experiments with 5-aminolevulanic acid (ALA) a clinically approved photiosensitizer (PS) and 635 nm laser light have yielded promising results, as follow: (1) (human cervical cancer (HeLa) cell line incubated, for 18 h, with 30 μg/ml of 5-ALA, treated with laser light dose of 50 J/cm² can produce 85% of cell killing (2) human larynx carcinoma (Hep2c) cell line incubated, for 7 h, with 55 μg/ml of 5-ALA, treated with laser light dose of 85 J/cm² can produce 75% of cell killing (3) human liver cancer (HepG2) cell line incubated, for 22–48 h, with 262 μg/ml of 5-ALA, treated with laser light dose of 120 J/cm² can produce 95% of cell killing (4) human muscle cancer (RD) cell line incubated, for 47 h, with 250 μg/ml of 5-ALA, treated with laser light dose of 80 J/cm² can produce 76% of cell killing (5) Human embryonic kidney (HEK293T) cell line incu-bated, for 18 h, with 400 μg/ml of 5-ALA, treated with laser light dose of 40 J/cm2 can produce 82% of cell killing confirming the efficacy of photodynamic therapy.     

Optical parameters measurement for diagnostic and photodynamic therapy of human cervical adenocarcinoma (HeLa) cell line

The purpose of this study was to investigate the optical properties, absorption coefficient (μ _a ) scattering coefficient (μ _s ) and refractive indices, (n) of HeLa cell line in a suspension of 2% minimum essential medium (MEM) at two different (632.8 and 532.0 nm) wave lengths of laser light. Optical properties were determined with Kubelka Munk Model (KMM) and refractive index measurement was made through minimum angle of deviation method (MAD). We reported μ _a = 8.643 ± 0.187 and 2.348 ± 0.249 cm⁻¹ and μ _s = 5.609 ± 0.287 and 88.166 ± 2.833 cm⁻¹ at 632.8 and 532.0 nm, respectively. Refractive index was found to be 1.332 and 1.312 at 632.8 nm and 532.0 nm, respectively. The discussed results provide a route of information for clinical diagnosis, therapeutic application and dosimetry studies in HeLa and other cell lines.     

Structure of 5-Allyl-2-hydroxy-3-methoxyazobenzene

Abstract

5-allyl-2-hydroxy-3-methoxyazobenzene was preperad by the reaction of 4-allyl-2-methoxyfenol and benzenediazoniumchloride and crystallized from dimethylsulphoxide to yield crystals suitable for analysis. The molecular structure was identified by UV-VIS, IR, ¹H-NMR, ¹³C-NMR and elemental analysis. The crystal structure of the title compound was determined as monoclinic by by single crystal X-Ray diffraction technique. The crystal parameters of this compound are as follows: monoclinic P 2 1/n, a=5.559(2) Å,b=14.900(2) Å, c= 17.573(29 Å, P = 98.58(1)?, V = 1439.3(2) ų, Z = 2, Dx = 0.610 g/cm³, F(OOO) = 284, λ (MoKα) = 0.71070 Å, μ = 0.041 mm^?1. The structure was solved by SHELXS-86 and refined by SHELXL-93. R = 0.09 for 1107 observed reflections with I > 2σ (I).     

Structure of Quinoline-4-Carboxaldehyde-2,4-Dinitrophenyl-N Methylhydrazone

Abstract

The crystal structure of the title compound, C₁₇H₁₃N₅O₄, has been determined by single crystal x-ray diffraction at room temperature. The molecule is not planar, with dihedral angles of 7.2(1)° between the quinoline ring and N-methylhydrazone group, and 17.45(2)° between the N-methylhydrazone group and the phenyl ring. The crystal parameters of this compound are as follows: monoclinic P 21/n, a=9.525(2)Å, b = 15.192(2) Å, c = 11.302(2) A, β = 94.722(3)°, V = 1629.8(6) ų, Z = 4, Dx = 1.432 g/cm³, F(000) = 728, λ (MoKα) = 0.71070 Å, μ = 0.106 mm^?1, R_int = 0.017. The structure was solved by SHELXS-86 and refined by SHELXL-93. R = 0.07 for 2438 observed reflections with I > 2σ (I).     

Polyacrylonitrile Block Copolymers for the Preparation of a Thin Carbon Coating Around TiO2 Nanorods for Advanced Lithium‐Ion Batteries

Herein, a new method for the realization of a thin and homogenous carbonaceous particle coating, made by carbonizing RAFT polymerization derived block copolymers anchored on anatase TiO₂ nanorods, is presented. These block copolymers consist of a short anchor block (based on dopamine) and a long, easily graphitizable block of polyacrylonitrile. The grafting of such block copolymers to TiO₂ nanorods creates a polymer shell, which can be visualized by atomic force microscopy (AFM). Thermal treatment at 700 °C converts the polyacrylonitrile block to partially graphitic structures (as determined by Raman spectroscopy), establishing a thin carbon coating (as determined by transmission electron microscopy, TEM, analysis). The carbon‐coated TiO₂ nanorods show improved electrochemical performance in terms of achievable specific capacity and, particularly, long‐term cycling stability by reducing the average capacity fading per cycle from 0.252 mAh g^–1 to only 0.075 mAh g^–1.

     

Enhanced Biodecolorization of Reactive Dyes by Basidiomycetes Under Static Conditions

This study presents the biodecolorization potential of basidiomycete fungi Trametes hirsuta, Pycnoporus sp., and Irpex sp. for different reactive dyes viz. Reactive Red 120, Remazol Brilliant Blue R (RBBR), Reactive Orange G, and Reactive Orange 16 under static and shaking conditions. The screening trials revealed that T. hirsuta exhibited maximum potential (83.75 %) for biodecolorization of RBBR dye under static conditions after the fifth day of incubation. However, the rate of biodecolorization of RBBR dye by Pycnoporus sp. was much slow and reached maximum (81.25 %) after 15 days of incubation under shaking conditions. By process optimization, enhanced decolorization (91.2 %) of RBBR by T. hirsuta was achieved at pH 5.5 within 24 h using a defined salt medium amended with p-coumaric acid under static conditions. pH was found to be an important parameter for the enzymatic system involved in RBBR dye decolorization by T. hirsuta and Pycnoporus sp. Biodecolorization of RBBR dye was determined by a reduction in optical density at the wavelength of maximum absorbance (λ, 578 nm) by UV–vis spectrophotometer. The shift in maximum wavelength toward shorter/longer wavelength in UV–vis scanning spectrum revealed the degradation of RBBR dye into different transformation products.     

Cross metathesis assisted solid-phase synthesis of glycopeptoids

A solid-phase synthesis of glycopeptoids was explored through olefin cross metathesis (CM). Peptoids and sugar derivatives with appropriate olefin moieties were coupled in the presence of an olefin metathesis catalyst to afford glycopeptoids in good yields. This systematic solid-phase CM study can provide facile access to the molecular sources of glycopeptidomimetics and postchemical modifications on various molecular scaffolds.     

Z-shaped meta-atom for negative permittivity metamaterials

A printed Z-shaped electric meta-atom is presented as an alternative design to the conventional electric-LC (ELC) resonator. We propose an easy way to redesign the ELC resonator pattern to get a compact and a low cost electric resonator exhibiting a strong electric response. Our approach involves, in the effective medium regime, redressing the resonator shape to accommodate higher inductance and lead to a lower resonance frequency without being limited by fabrication tolerances. The electromagnetic behaviour of the meta-atom has been investigated through both simulations and experiments in the microwave regime. Our results show that the Z meta-atom exhibits an electric response to normally incident radiation and can be used very effectively in producing materials with negative permittivity. The proposed planar meta-atom can find various applications in high frequency passive circuits which are designed in planar technology. Moreover, the proposed structure can be scaled to much higher frequencies via appropriate lithographic scaling.