Two-Stage Hybrid Gene Selection Using Mutual Information and Genetic Algorithm for Cancer Data Classification.

Cancer is a deadly disease which requires a very complex and costly treatment. Microarray data classification plays an important role in cancer treatment. An efficient gene selection technique to select the more promising genes is necessary for cancer classification. Here, we propose a Two-stage MI-GA Gene Selection algorithm for selecting informative genes in cancer data classification. In the first stage, Mutual Information based gene selection is applied which selects only the genes that have high information related to the cancer. The genes which have high mutual information value are given as input to the second stage. The Genetic Algorithm based gene selection is applied in the second stage to identify and select the optimal set of genes required for accurate classification. For classification, Support Vector Machine (SVM) is used. The proposed MI-GA gene selection approach is applied to Colon, Lung and Ovarian cancer datasets and the results show that the proposed gene selection approach results in higher classification accuracy compared to the existing methods.

3D nanorhombus nickel nitride as stable and cost-effective counter electrodes for dye-sensitized solar cells and supercapacitor applications.

Transition metal nitride based materials have attracted significant interest owing to their excellent properties and multiple applications in the field of electrochemical energy conversion and storage devices. Herein we synthesize 3D nanorhombus nickel nitride (Ni3N) thin films by adopting a reactive radio frequency magnetron sputtering process. The as-deposited 3D nano rhombus Ni3N thin films were utilized as cost-effective electrodes in the fabrication of supercapacitors (SCs) and dye-sensitized solar cells (DSSCs). The structure, phase formation, surface morphology and elemental composition of the as-deposited Ni3N thin films were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS) and atomic force microscopy (AFM). The electrochemical supercapacitive performance of the Ni3N thin films was examined by cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) techniques, in 3 M KOH supporting electrolyte. The areal capacitance of the Ni3N thin film electrode obtained from CV analysis was 319.5 mF cm-2 at a lower scan rate of 10 mV s-1. Meanwhile, the Ni3N thin film showed an excellent cyclic stability and retained 93.7% efficiency of its initial capacitance after 2000 cycles at 100 mV s-1. Interestingly, the DSSCs fabricated with a Ni3N CE showed a notable power energy conversion efficiency of 2.88% and remarkable stability. The prominent performance of the Ni3N thin film was ascribed mainly due to good conductivity, high electrochemically active sites with excellent 3D nano rhombus structures and high electrocatalytic activity. Overall, these results demonstrate that the Ni3N electrode is capable of being considered for efficient SCs and DSSCs. This investigation also offers an essential directive for the advancement of energy storage and conversion devices.

Gamma-Irradiation Effects on the Spectral and Amplified Spontaneous Emission (ASE) Properties of Conjugated Polymers in Solution.

In this paper, we investigate the effects of gamma (γ) radiation on the spectral and mplified spontaneous emission (ASE) properties of two conjugated polymers (CPs) viz., poly [2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH⁻PPV) (CPM) and poly{[2-[2',5'-bis(2″-ethylhexyloxy)phenyl]-1,4-phenylenevinylene]-co-[2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylene vinylene]} (BEHP-co-MEH⁻PPV) (BMP) in tetrahydrofuran (THF). Gamma irradiation strongly affected the photophysical properties of these CPs. To explore these changes, gamma radiation, in the range of 2⁻50 kGy, was used to maintain the temperature at 5 °C constant for all doses at a dose rate of 12.67 kGy/h, using a 60Co gamma ray. The ASE profiles of the CPs in THF were obtained under the high power excitation of a Nd:YAG laser (355 nm), pre- and post-radiation. The result revealed a dramatic blue shift of the fluorescence and the ASE spectra after gamma irradiation. This shift in the luminescence and ASE spectra could be a response to the conformational disorders such as gamma irradiation-induced polymer crosslinking, which was verified using Raman spectra, FTIR, and swelling experiments. This could be the first report on the effect of gamma radiation on the ASE properties of conjugated polymers.

Laser from Optically Pumped Quantum Dot CdSe/ZnS in a Colloidal Liquid.

In this study, we had investigated the amplified spontaneous emission (ASE) characteristics of CdSe/ZnS quantum dot (QDs) in a colloidal liquid. A third harmonic of Nd:YAG laser (355 nm) was used to produce laser-induced fluorescence (LIF) at 605 nm with a spectral width of 0 nm [full width at half maximum (FWHM)]. When the pump power and focusing were carefully optimized, an ASE at 610 nm with a spectral width of Δλ = 8 nm (FWHM) could be obtained. The beam was directional with a divergence of 10 milli radians (mrad); but the conversion efficiency was about 0.05%.