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Zinc Oxide (ZnO) nanoparticle was synthesized using rhizome extracts of Zingiber officinale for in-vitro anti-cancer study in our previous paper. Treated with ZnO nanoparticle with Zingiber officinale extracts (ZGNPE) showed significant inhibition on the human chronic myeloid leukemia cells whereas in normal human embryonic kidney cells showed insignificant toxicity. Therefore, further more we evaluate the cytotoxic activity of ZnO nanoparticle with Zingiber officinale extracts on human ovarian cancer cells (SKOV-3). Cytotoxic activity was performed by MTT assay. Treated with ZGNPE sample 4,5 and 6 showed significant inhibition on the SKOV-3 cancer cells. The IC50 values were 48.49 µg for ZGNP-4, 39.83µg for ZGNP-5 and 45.36 µg for ZGNP-6 respectively. Thus, ZGNPE may be used as chemotherapy drug and an enormous medical application with less toxicity in future. The characterization of nanoparticle was confirmed using ultraviolet spectroscopy and Fourier Transfer Infrared Spectroscopy (FTIR). The ZGNPE characterization also used the UV-Vis Spectrophotometer spectrum technique to measure the structural characterization of nanoparticles by determine the absorbance measurement.

Zinc Oxide (ZnO) nanoparticle was synthesized using rhizome extracts of Zingiber officinale for in-vitro anti-cancer study. The characterization of nanoparticle was confirmed using ultraviolet spectroscopy and Fourier Transfer Infrared Spectroscopy (FTIR). The ZGNPE characterization also used the UV-Vis Spectrophotometer spectrum technique to measure the structural characterization of nanoparticles by determine the absorbance measurement. Cytotoxic activity of myelogenous leukemia cells (K562) and normal human embryonic Kidney (HEK293T) cells were performed by MTT assay. Treated with ZnO nanoparticle with Zingiber officinale extracts (ZGNPE) showed significant inhibition on the cancer cells whereas in normal cell showed insignificant toxicity. Thus, ZGNPE may be used as chemotherapy drug and an enormous medical application with less toxicity in future. Further mechanistic studies are in progress.

A W-band compact Dual Reflector Cassegrain antenna with high gain, pencil beam and good sidelobe level has been designed using High Frequency Structure Simulator (HFSS) IE software. The proposed antenna consist of a Main reflector, Sub reflector and a Feed all together joined with a support structure made of Aluminum. Simulated and Experimental measured results for various antenna parameters show a very good agreement. Effect of support structure has also been studied and optimized to minimize the effect on electrical properties of the antenna.

An airborne or space borne microwave Synthetic Aperture Radar (SAR) system is used for very high resolution imaging purpose and has advantages over optical imaging system. Its performance is not limited by severe weather conditions like fog, snow or clouds and it is also independent of day-night conditions. In this paper the authors formed a SAR image using Chirp Scaling Algorithm (CSA) of an Indian coastal area using actual SAR Data. The CSA is selected in view of reduced computation time and to make the processing independent of interpolations. The main processing operations FFTs, IFFTs, Phase multiplications and additions of CSA are described in detail. The CSA is first verified with simulated point target data and then it is used for processing of actual SAR data. SAR image is formed and main features are compared with google image of the same area. A very good matching is observed.

A microwave synthetic aperture radar (SAR) system is used for very high resolution imaging purpose. In this paper the authors formed SAR images with Doppler Beam Sharpening (DBS) algorithm, Range Doppler Algorithm (RDA), Chirp Scaling Algorithm (CSA) and Omega-K Algorithm (ωKA) using ERS satellite SAR data, and are analyzed by measuring the Impulse Response Function (IRF) of a point target in the images. The results are summarized and compared.

The paper describe a computer-based method to calculate the series resistance Rs of a millimeter wave Ka-band packaged IMPATT diode from small signal conductance-susceptance characteristics. The series resistance Rs has been calculated at the threshold condition when the small signal conductance of the packaged diode just becomes negative and the device susceptance becomes positive. Again, the value of series resistance Rs has been determined from the measurement of threshold current and threshold frequency with the silicon Ka-band IMPATT diode embedded in a resonant cap cavity which agrees well with the values obtained by the computer method.Defence Science Journal, 2009, 59(2), pp.189-193, DOI:http://dx.doi.org/10.14429/dsj.59.1508

The paper describes the studies of the tuning properties of an indigenously developed resonant-cap continuous wave IMPATT oscillator at Ka-band by changing circuit susceptance through mechanical tuning. It was observed that output power of a resonant-cap IMPATT oscillator passes through a maximum at a particular frequency for a given diode with an optimum combination of cap diameter and cap height. An empirical relation has been found between cap diameter and wavelength of the optimised oscillator, which agrees with the theoretical relation. The effect of sliding short tuner position on the oscillator at optimised condition and the phenomenon of frequency jump in certain positions of sliding short have been studied.

Biophytum sensitivum linn. (Oxalidaceae), is an important and widely used medicinal plant. Biophytum sensitivum linn. is used as a traditional folk medicine in ailments such as inflammation, arthritis, wounds, tumors and burns, gonorrhea, stomach ache, asthma, cough, degenerative joint disease, urinary calculi, diabetes, snake bite, amenorrhea and dysmenorrhea.. The total flavonoid content of methanolic whole plant extract of B. sensitivum (MEBS) was determined by using aluminium chloride colorimetric method. Flavonoid compounds were found to be 9.49 µg of quercetin equivalent [QE] per mg of methanolic whole plant extract of Biophytum sensitivum. In this study phytochemical analysis of methanolic extract of B. sensitivum L. has indicated the presence of flavonoid . Since these compounds are of pharmacological interest, coupled with the use of this plant in traditional medicine, it prompted us to check B.sensitivum  L. for possible antioxidant activity by DPPH scavenging activity and reducing power ability. The maximum percentage inhibition by DPPH method was found about 43.96 at concentration of 110.46µg/ml, when compared with Quercetin. The reducing capabilities were found to be in dose dependent manner. Key words: Biophytum sensitivum, aluminium chloride, quercetin, DPPH.

A computer based method to determine the series resistance of silicon Ka- band IMPATT diode from Small signal threshold condition is described. The values of series resistance are found to be 0.904 ohm - 1.013 ohm over a feasible range of current density 9.0 times 107 Amp/m2 - 1.2 times 108 Amp/m2 . The results obtained by the computer method agree well with the experimentally measured values of Series resistance 1.008 ohm - 1.067 ohm for various cap heights.

In the present scenario, gene prediction methods use only one model to represent protein-coding regions in a genome, and so the chances of predicting the location of genes that have a typical sequence composition is rare. It is predicted that future improvements in gene finding will be based on various methods of development that can adequately deal with intra-genomic compositional variation. This work explores a new approach to gene prediction, based on the self-organising map (SOM), which has the ability to automatically identify multiple gene models within a genome. The current implementation, named codon usage information (CUI), uses relative synonymous codon usage (RSCU) as the indicator of protein-coding potential. Though the raw accuracy rate is considered less than other methods, CUI consistently identifies some genes that other methods do not, and should therefore be of interest to gene prediction software developers and people working on genome annotation. CUI is recommended for use in conjunction with, or as a complement to, other gene prediction methods.