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1.
J Nanosci Nanotechnol ; 18(2): 1019-1026, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29448527

RESUMO

Ni-doped cobalt aluminate NixCo1-xAl2O4 (x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0) spinel nanoparticles were successfully synthesized by a simple microwave combustion method using urea as the fuel and as well as reducing agent. X-ray powder diffraction (XRD) was confirmed the formation of single phase, cubic spinel cobalt-nickel aluminate structure without any other impurities. Average crystallite sizes of the samples were found to be in the range of 18.93 nm to 21.47 nm by Scherrer's formula. Fourier transform infrared (FT-IR) spectral analysis was confirmed the corresponding functional groups of the M-O, Al-O and M-Al-O (M = Co and Ni) bonds of spinel NixCo1-xAl2O4 structure. Scanning electron microscope (SEM) and transmission electron microscope (TEM) images was confirmed the particle like nanostructured morphology. Energy band gap (Eg) value was calculated using UV-Visible diffuse reflectance spectra (DRS) and the Eg values increased with increasing Ni2+ dopant from x = 0.2 (3.58 eV) to x = 1.0 (4.15 eV). Vibrating sample magnetometer (VSM) measurements exposed that undoped and Ni-doped CoAl2O4 samples have superparamagnetic behavior and the magnetization (Ms) values were increased with increasing Ni2+ ions. Spinel NixCo1-xAl2O4 samples has been used for the catalytic oxidation of benzyl alcohol into benzaldehyde and was found that the sample Ni0.6Co0.4Al2O4 showed higher conversion 94.37% with 100% selectivity than other samples, which may be due to the smaller particle size and higher surface area.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 288: 122196, 2023 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-36473294

RESUMO

Anthracene based chemosensor ABC has been synthesized and characterized through 1H, 13C NMR, mass spectral studies. UV absorption and emission studies performed to identify the sensing behavior of chemosensor ABC. The probe ABC, originally bright fluorescent, selectively sense Ag+ ion by the quenching the fluorescence intensity through a "Switch On-off" process and quench the fluorescence due to the heavy atom effect interaction with the free chemosensor. The binding constant of the probe ABC with Ag+ was calculated as 5.4 × 104 M-1 and the limit of detection upto 1.4 nM level. The practical utilization of the probe ABC was demonstrated by applying to the real water and soil sample analysis, latent finger print, and the sensor as a fluorescent ink.


Assuntos
Benzeno , Bases de Schiff , Espectrometria de Fluorescência , Bases de Schiff/química , Corantes Fluorescentes/química , Fluorometria , Antracenos
3.
Clin Exp Obstet Gynecol ; 36(1): 35-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19400416

RESUMO

OBJECTIVE: To evaluate the predictive value for successful labor induction of transvaginal ultrasound (TVS) of cervical length according to parity. METHOD: TVS of the cervix was performed before term labor induction. Induction was considered successful if vaginal delivery was achieved within 24 hours; 231 women were available for final analysis. RESULTS: Analysis of the receiver operator characteristics curve showed an optimal cut-off for cervical length of < or = 20 mm for successful induction. Following multivariate logistic regression analysis, a sonographic short cervix (AOR 5.6; p < 0.001) was an independent predictor of successful induction but not a favorable Bishop score (p = 0.47). Among multiparas with a short cervix, positive and negative predictive values for successful induction were 98% (95% CI 90-100%) and 21% (95% CI 13%-32%) and among nulliparas, predictive values were 69% (95% CI 53%-82%) and 77% (95% CI 64%-87%) respectively. CONCLUSION: In nulliparas, cervical length can usefully predict labor induction outcome.


Assuntos
Colo do Útero/anatomia & histologia , Colo do Útero/diagnóstico por imagem , Trabalho de Parto Induzido , Exame Físico , Administração Intravaginal , Adulto , Estudos de Coortes , Dinoprostona/administração & dosagem , Feminino , Humanos , Ocitócicos/administração & dosagem , Paridade , Valor Preditivo dos Testes , Gravidez , Terceiro Trimestre da Gravidez , Curva ROC , Ultrassonografia
4.
J Microbiol Methods ; 66(1): 174-6, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16406130

RESUMO

To establish the gene transfer system in the cyanobacteria, we successfully introduced the shuttle plasmid pRL489 into Oscillatoria MKU 277 by electroporation with transformation frequencies of up to 102 cfu/mug of plasmid DNA. These findings suggest that Oscillatoria MKU 277 can be used as an experimental tool for genetic maneuvering.


Assuntos
Cianobactérias/genética , Eletroporação , Técnicas de Transferência de Genes , Plasmídeos/genética , Transformação Bacteriana
5.
Data Min Knowl Discov ; 10(8): 3806-3825, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28003793

RESUMO

This paper brings out a neoteric frame of reference for visual semantic based 3d video search and retrieval applications. Newfangled 3D retrieval application spotlight on shape analysis like object matching, classification and retrieval not only sticking up entirely with video retrieval. In this ambit, we delve into 3D-CBVR (Content Based Video Retrieval) concept for the first time. For this purpose, we intent to hitch on BOVW and Mapreduce in 3D framework. Instead of conventional shape based local descriptors, we tried to coalesce shape, color and texture for feature extraction. For this purpose, we have used combination of geometric & topological features for shape and 3D co-occurrence matrix for color and texture. After thriving extraction of local descriptors, TB-PCT (Threshold Based- Predictive Clustering Tree) algorithm is used to generate visual codebook and histogram is produced. Further, matching is performed using soft weighting scheme with L2 distance function. As a final step, retrieved results are ranked according to the Index value and acknowledged to the user as a feedback .In order to handle prodigious amount of data and Efficacious retrieval, we have incorporated HDFS in our Intellection. Using 3D video dataset, we future the performance of our proposed system which can pan out that the proposed work gives meticulous result and also reduce the time intricacy.

6.
Indian J Exp Biol ; 38(4): 402-4, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11218822

RESUMO

Four isolates of Oscillatoria sp from an Indian paddy field have been tested for their tolerance to agrochemicals and pyrethroid components. The isolates possessed considerable tolerance to agrochemicals and reduced toxicity of pyrethroid components towards fish.


Assuntos
Agroquímicos/farmacologia , Cianobactérias/efeitos dos fármacos , Agroquímicos/toxicidade , Animais , Biodegradação Ambiental , Cianobactérias/isolamento & purificação , Cianobactérias/metabolismo , Oryza/microbiologia , Piretrinas/farmacologia , Piretrinas/toxicidade , Tilápia
7.
Artigo em Inglês | MEDLINE | ID: mdl-24878440

RESUMO

Piperazine-1,4-diium bis 2,4,6-trinitrophenolate is one of the useful organic materials with nonlinear optical (NLO) and pharmaceutical applications. The material was grown by slow evaporation solution growth method at room temperature. The crystal system and lattice parameters were identified by single crystal XRD analysis. The grown material crystallizes in monoclinic system with P21/n space group. The main functional groups NH2, NO2, CN, CC, and phenolic 'O' atom were identified using FTIR analysis. The protons and carbons of grown crystal with various chemical environments were studied by 1H and 13C NMR spectroscopy to confirm the molecular structure. The optical properties of the crystal were studied by UV-vis-NIR spectroscopy and the transmission 100% range starts from 532 nm onwards. The optical band gap was measured as 2.63 eV from the plot of (αhν)2 versus hν. The thermal stability was detected at 304.1°C using TG-DTA analysis. The dielectric studies of the sample were carried out at different temperatures in the frequency range from 50 Hz to 5 MHz to establish the dielectric nature of the crystal. Photoconductivity measurements were carried out on the grown crystal. The Second Harmonic Generation (SHG) of the crystal was tested to confirm the nonlinear optical property.


Assuntos
Nitrocompostos/química , Dinâmica não Linear , Fenômenos Ópticos , Piperazinas/química , Piperazinas/síntese química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Cristalização , Cristalografia por Raios X , Análise Diferencial Térmica , Condutividade Elétrica , Conformação Molecular , Piperazina , Espectroscopia de Prótons por Ressonância Magnética , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Espectroscopia de Luz Próxima ao Infravermelho , Temperatura
8.
Iran J Microbiol ; 2(3): 157-64, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22347566

RESUMO

BACKGROUND AND OBJECTIVES: In the present study, isolation of Streptomyces associated with marine sponges and its bioactive potential against fish and shellfish pathogens were assessed. The Streptomyces sp. were isolated from the marine sponges namely Callyspongia diffusa, Mycale mytilorum, Tedania anhelans and Dysidea fragilis collected from Vizhinjam port, situated in the South-West coast of India. MATERIALS AND METHODS: The Streptomyces associated with marine sponges were isolated using specific ISP media. The isolates of Streptomyces were characterized for their colony characteristics, morphological properties, physiological and biochemical properties and were tentatively identified. The strains were cultivated on a lab scale level as shake-flask cultures and the crude extracts of the bioactive compounds obtained with ethyl acetate were screened biologically and chemically. By biological screening, the extracts were analyzed for their activity against fish and shellfish pathogens namely Aeromonas hydrophila, Serratia sp. and Vibrio spp, using the disk and agar-well diffusion bioassay method, while by chemical screening the crude culture extracts were analyzed by TLC and UV-Vis spectrophotometer. RESULTS: Ninety-four isolates were found to be associated with marine sponges, among them only seven strains showed antagonism against fish and shellfish pathogens. Analysis of morphological, physiological and biochemical characteristics suggested that these strains belonged to the genus Streptomyces. The initial screening of the isolates by spot inoculation method exhibited antibacterial activity against Aeromonas hydrophila. In-vitro screening of the submerge culture extracts showed positive inhibition against the fish and shellfish pathogens namely Aeromonas hydrophila, Serratia sp. and Vibrio spp. The screening of bioactive compounds confirmed the production of polyene substances by UV spectrum, which resulted in absorbance peaks ranging from 225 to 245 nm and TLC analysis yielded R(f) values ranging from 0.40 to 0.78. CONCLUSION: The results suggest that the seven Streptomyces strains isolated from marine sponges produce potential antibacterial compounds against fish and shellfish pathogens.

13.
Indian J Med Res ; 73 Suppl: 120-3, 1981 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7287087
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