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91.
Pachaiappan Rekha Prakasarao Aruna Ganesan Bharanidharan Dornadula Koteeswaran Munusamy Baludavid Singaravelu Ganesan 《Journal of Raman spectroscopy : JRS》2015,46(9):735-743
The metabolic end products from cells/tissues that are released into the circulating blood stream and any changes in their level because of pathological conditions may be used as markers in disease diagnosis. Raman spectroscopy has been exploited to characterize the biomolecules present in the blood plasma of clinically confirmed normal group, premalignant (Oral Sub Mucous Fibrosis) and malignant (Oral Squamous Cell Carcinoma) at 784.15 nm. Raman spectral signatures show relatively less intense Raman bands of phenylalanine, lipid and antioxidant beta carotene but higher intense bands for proteins, DNA base components and amino acids (tyrosine and tryptophan) for malignant group than that of normal group. However premalignant group possess high intense Raman bands for amino acids (tyrosine and tryptophan) at 830, 1020 and 1620 cm−1 and protein peaks at 913, 978 and 1646 cm−1 when compared to that of malignant and normal group. Principal component analysis coupled with linear discriminant analysis (PCA‐LDA) yielded a diagnostic sensitivity of 96.3% and 91.2%, and a specificity of 80.0% and 96.7% in the classification of normal from premalignant and normal from malignant, respectively. This indicates that Raman spectroscopy of blood plasma has the potential in classifying normal and oral malignancy conditions. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
92.
Synthesis of cadmium sulphide in pure and mixed Langmuir-Blodgett films of n -octadecylsuccinic acid
G. Hemakanthi Balachandran Unni Nair Aruna Dhathathreyan 《Journal of Chemical Sciences》2000,112(2):109-118
Cadmium sulphide (CdS) nanoparticles were grown by the reaction of sodium sulphide (Na2S) with Langmuir-Blodgett (LB) films of cadmium salts ofn-octadecylsuccinic acid (ODSU) and with LB films of ODSU in mixtures of octadecylamine and octadecyl alcohol. The results
indicate that heterogeneous nucleation and aggregation in the pure ODSU LB films due to processes like Ostwald ripening are
destabilized by the presence of the long-chain amine and alcohol in mixed systems. CdS nanoparticles in the LB films were
monitored by UV-visible absorption spectra, which allow an estimation of the size of the particles. The morphology, size and
nature of the nanocrystallites formed depend on whether the sulphidation was done on the pure film or in the mixed films.
It is seen that particles of size around 1.6 nm were formed in ODSU/octadecylalcohol and ODSU/ octadecylamine mixed LB films
while in pure ODSU films the size was about 2.7 nm. These films showed typical needle-shaped structures, as observed by the
optical microscopic technique. Mean size and morphology were confirmed by transmission and scanning electron microscopy, while
selective area electron diffraction patterns showed six-fold symmetry and indicated that the CdS crystals grow epitaxially
with respect to the monolayer. Further, the crystallisation enhanced in the mixed LB films showed a characteristic zinc oxide
(Wurtzite) structure compared with the pure ODSU matrix. 相似文献
93.
Aruna J. Weerasinghe 《Tetrahedron letters》2009,50(46):6407-3526
A new fluorescent sensor capable of sensing Cr3+ has been synthesized. Complexing with Cr3+ triggers the formation of a highly fluorescent ring-open form which is pink in color. The sensor shows extremely high fluorescence enhancement upon complexation with Cr3+ and it can be used as a ‘naked eye’ sensor. Binding of Cr3+ was found to be reversible as the pink color disappears with excess EDTA. 相似文献
94.
Haraguchi K Delaney MO Wiederholt CJ Sambandam A Hantosi Z Greenberg MM 《Journal of the American Chemical Society》2002,124(13):3263-3269
Oligodeoxynucleotides containing formamidopyrimidine lesions and C-nucleoside analogues at defined sites were prepared by solid-phase synthesis and in some cases enzymatic ligation. Formamidopyrimidine lesions were introduced as dinucleotides to prevent rearrangement to their pyranose isomers. Oligodeoxynucleotides containing single diastereomers of C-nucleoside analogues of Fapy.dA were introduced by using the respective phosphoramidites. The formamidopyrimidine lesions reduce the T(M) of dodecamers relative to their unmodified nucleotide counterparts when opposite the nucleotide proper base-pairing partner. However, duplexes containing Fapy.dG-dA mispairs melt significantly higher than those comprised of dG-dA. All duplexes containing Fapy.dA-dX or its C-nucleoside analogue melt lower than the respective complexes containing dA-dX. Studies of the alkaline lability of oligodeoxynucleotides containing formamidopyrimidine lesions indicate that Fapy.dA is readily identified as an alkali-labile lesion with use of piperidine (1.0 M, 90 degrees C, 20 min), but Fapy.dG is less easily identified in this manner. 相似文献
95.
An expression for the width of the plasmon excitations in electron liquid has been obtained using the mode coupling approximation. It is shown that the exact weak coupling (rs → 0) results of the plasmon width in the long wavelength limit is obtained as a very special case in this approach. 相似文献
96.
Aruna Sharma 《Discrete Mathematics》1984,49(2):201-203
This note provides counter-examples to a conjecture of D.A. Holton on stability of graphs. It is shown that even though the automorphism groups of two graphs are identical, one may be stable while the other is not. 相似文献
97.
A fractal analysis is made for antigen-antibody binding kinetics for different biosensor applications available in the literature.
Both types of examples are considered wherein: (1) the antigen is in solution and the antibody is immobilized on the fiberoptic
surface, and (2) the antibody is in solution and the antigen is immobilized on the fiberoptic surface. For example, when the
antibody is immobilized on the surface, an increase in the antigenClostridium botulinum toxin A concentration in solution leads to (1) a decrease in the fractal dimension value or state of disorder, and (2) a
higher rate constant for binding on the fiberoptic surface. An analysis of the effect of the influence of different parameters
on the fractal dimension values for a particular example, such as varying treatments or incubation procedures, helps provide
insights into the conformational states and reactions occurring on the fiberoptic surface. The analysis of the different examples
taken together provides novel physical insights into the state of “disorder” and reactions occurring on the surface. Such
types of analysis should help contribute toward manipulating the reactions occurring on the fiberoptic surfaces in desired
directions. 相似文献
98.
Adhikary R Bose S Mukherjee P Thite A Kraus GA Wijeratne AB Sharma PS Armstrong DW Petrich JW 《The journal of physical chemistry. B》2008,112(25):7555-7559
The synthesis and decolorization of chiral room-temperature ionic liquids based upon 1-methyl imidazole and chloromethyl menthyl ether is reported. The excellent optical quality of these solvents permits the investigation of the effects of the two enantiomers on the excited-state photophysics of (S)-N-methyl-2-pyrrolidinemethyl 2(S)-(6-methoxy-2-naphthyl)propionate [(S,S)-NPX-PYR]. Whereas in conventional bulk polar solvents such as acetonitrile, (S,S)-NPX-PYR is known to execute excited-state intramolecular electron transfer and to form exciplexes, in these chiral solvents these nonradiative processes are absent. The chiral solvents do, however, induce a small but reproducible (approximately 10%) stereodifferentiation in the fluorescence lifetime of (S,S)-NPX-PYR as well as in the parent compound, (S)-naproxen. To our knowledge, this is the first example of chiral ionic liquids inducing such an effect on photophysical properties. 相似文献
99.
Keyzers RA Daoust J Davies-Coleman MT Van Soest R Balgi A Donohue E Roberge M Andersen RJ 《Organic letters》2008,10(14):2959-2962
Clionamines A-D (1- 4), new aminosteroids that modulate autophagy, have been isolated from South African specimens of the sponge Cliona celata. Clionamine D (4) has an unprecedented spiro bislactone side chain. 相似文献
100.
Russian Journal of Organic Chemistry - A green synthesis of 2-oxo-2H-chromene-3-carbonitriles has been carried out in one step by reacting 2-hydroxybenzaldehydes or 2-hydroxyacetophenones with... 相似文献