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31.
Gao J Friedrichs MS Dongre AR Opiteck GJ 《Journal of the American Society for Mass Spectrometry》2005,16(8):1231-1238
A set of guidelines has been developed for using the peptide hits technique (PHT) as a semi-quantitative screening tool for the identification of proteins that change in abundance in a complex mixture. The dataset that formed the basis for these experiments was created using a cell lysate derived from the yeast Saccharomyces cerevisiae, spiked at various levels with serum albumin (BSA), and analyzed by LC/MS/MS and SEQUEST. Knowing that the level of only one protein (BSA) actually changed in the mixture allowed for the development and refinement of the necessary bioinformatics and statistical analyses, e.g., principal component analysis (PCA), normalization, and analysis of variation (ANOVA). As expected, the number of BSA peptide hits changed in proportion to the amount of BSA added to the sample. PCA was able to clearly distinguish between the spiked samples and the untreated sample, indicating that PCA may be able to classify samples, e.g., healthy versus diseased, in future experiments. The use of an endogenous "housekeeping" protein was found to be superior to the use of total hits for data normalization prior to analysis. An ANOVA based model readily identified BSA as a protein of interest, that is, one likely to be changing from amongst the background proteins, indicating that an ANOVA model may be able to identify individual proteins in target or biomarker discovery experiments. General guidelines based on these combined observations are set forth for future analyses and the rapid screening for candidate proteins of interest. 相似文献
32.
N. R. Dhumane S. S. Hussaini V. G. Dongre P. Ghugare M. D. Shirsat 《Applied Physics A: Materials Science & Processing》2009,95(3):727-732
Single crystal of L-Alanine-doped Zinc Thiourea Chloride (ZTC) was grown by slow evaporation technique. L-Alanine was added
in saturated ZTC solution by molar percent. The second-harmonic generation efficiency was studied by Kurtz and Perry powder
SHG test for 1, 2, and 3 mole% L-Alanine-doped ZTC and compared with pure ZTC. We observed enhancement in the SHG efficiency
of L-Alanine-doped ZTC. Higher enhancement was observed for 3 mole% L-Alanine-doped ZTC. Incorporation of L-Alanine in the
crystal was confirmed by energy dispersive X-ray analysis (EDAX). The Fourier transform infrared spectroscopy (FTIR) qualitatively
confirms the presence of all the functional groups. The unit cell parameters and crystal structure were determined by single
crystal X-ray diffraction. The UV-visible absorption spectra of L-Alanine-doped ZTC show excellent transmittance from 300 nm
to 1100 nm. The thermal stability of the grown crystal was also studied by thermo-gravimetric analysis (TGA). 相似文献
33.
S. S. Hussaini N. R. Dhumane G. Rabbani P. Karmuse V. G. Dongre M. D. Shirsat 《Crystal Research and Technology》2007,42(11):1110-1116
Non linear optical (NLO) materials have acquired new significance with the advent of a large number of devices utilizing solid‐state laser sources. Several NLO materials have been used for this kind of technological applications. The Potassium di‐hydrogen phosphate (KDP) one of NLO material having superior non linear optical properties has been exploited for variety of applications. In the present investigation we have grown KDP crystals from aqous solution with thiourea, an organic non linear optical material. We could enhance the SHG efficiency of thiourea doped KDP crystal. It was 1.99 times more that of pure KDP. We observed more enhancements in nonlinearity for low concentration of thiourea.The crystal structure and cell parameters of grown crystal were determined from Powder XRD.The incorporation of thiourea in the grown crystals was qualitatively analyzed from FT‐IR study. The absorption spectra of pure and thiourea doped KDP crystal reveal that thiourea doped KDP crystals would be a better nonlinear optical (NLO) material for second harmonic generation (SHG) than pure KDP. The thermal decomposition and weight loss of pure and thiourea doped KDP crystal was observed by thermogravimetric (TGA) analysis and Differential Scanning Calorimetry (DSC). The high frequency dielectric study of pure KDP crystal, thiourea doped KDP crystals and organic additive thiourea was carried out using X‐band at frequency 8GHZ and 12GHZ by transmission line wave guide method. We observed low dielectric constant of thiourea doped KDP crystal when it is doped with 2mole% of thiourea. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
34.
N. R. Dhumane S. S. Hussaini V. G. Dongre P. P. Karmuse M. D. Shirsat 《Crystal Research and Technology》2009,44(3):269-274
Single crystal of 2 mol% glycine doped Bis Thiourea Cadmium Chloride, a semi organic nonlinear optical material has been grown by slow evaporation technique. Good quality single crystal with dimension 14 × 12 × 5 mm3 was harvested after 35 days. The influence of amino acid glycine was studied for 1, 2 and 3 mol% glycine doped Bis Thiourea Cadmium Chloride by Kurtz and Perry powder second harmonic generation test and compared with pure Bis Thiourea Cadmium Chloride which confirms the enhancement of second harmonic generation property of glycine doped Bis Thiourea Cadmium Chloride. The large enhancement was found for 2 mol% glycine doping. The grown crystal was characterized by various characterizations viz. single crystal X‐ray diffraction, energy dispersive X‐ray (EDAX), Fourier Transform Infrared Spectroscopy (FTIR) analysis, UV‐visible absorption, thermo gravimetric analysis (TGA). (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献