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1.
Determination of antioxidant potential of Acacia nilotica leaf extract in oxidative stress response system of Saccharomyces cerevisiae
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2.
IP in the edge and ATM in the core are commonplace in today's internetworks. The IETF has proposed a new Quality of Service (QoS) mechanism namely Differentiated Services (DiffServ) for IP networks. On the other hand, QoS is an inherent feature in ATM. It is imperative that IP and ATM QoS interoperate efficiently to provide an end-to-end service guarantee. DiffServ provides a class of service named Assured Forwarding (AF) that does not exactly correlate to any of the service categories offered by ATM. AF is targeted towards a range of applications, such as real-time (rt) that do not require a constant bit rate service provided by Expedited Forwarding, and other non-real-time (nrt) applications that expect a service better than best effort. In this paper we propose the mapping of AF to the Variable Bit Rate (VBR) service category in ATM. VBR is suitable because it is available in the form of rt-VBR and nrt-VBR and could be translated appropriately based on the applications. The mapping is implemented and verified using the LBNL Network Simulator. The results of the experiments show that VBR is a better match for AF than any other service category in ATM. 相似文献
3.
A quantitative structure-activity relationship (QSAR) study on some sulfolanes and arylthiomethanes acting as human immunodeficiency virus-1 (HIV-1) protease inhibitors reveals that in the case of sulfolanes an octahydropyrindene ring and a five-membered 3(S)-sulfolane ring with a hydrophobic 2-substituent (cis to 3-substituent) will be crucial for the inhibition activity. The binding of a sulfolane, which is a nonpeptidic molecule, with the enzyme is shown to partly mimic the binding of a peptidic inhibitor. The 2-substituent is found to have strong hydrophobic interaction with the receptor. Similarly, in the case of arylthiomethanes, one of the substituents of the methane is found to have strong hydrophobic interaction with the enzyme, while the aryl substituent (4-hydroxy-6-phenyl-2-oxo-2H-pyran-3-yl) is assumed to be involved in the hydrogen bondings. 相似文献
4.
Ganeshkumar M Ravi Vinayakumar Sowmya V Gopalakrishnan E. A Soman K. P Chakraborty Chinmay 《Multimedia Tools and Applications》2022,81(25):36257-36273
Multimedia Tools and Applications - Intracranial Haemorrhage (ICH) occurring due to any injury to the brain is a fatal condition and its timely diagnosis is critically important. In this work, we... 相似文献
5.
This paper provides an alternative framework for color-to-grayscale image conversion by exploiting the chrominance information present in the color image using singular value decomposition (SVD). In the proposed technique of color-to-grayscale image conversion, a weight matrix corresponds to the chrominance components is derived by reconstructing the chrominance data matrix (planes a* and b*) from the eigenvalues and eigenvectors computed using SVD. The final grayscale converted image is obtained by adding the weighted chrominance data to the luminous intensity which is kept intact for the CIEL*a*b* color space of the given color image. The effectiveness of the proposed grayscale conversion is confirmed by the comparative analysis performed on the color-to-gray benchmark dataset across 10 existing algorithms based on the standard objective measures, namely normalized cross-correlation, color contrast preservation ratio, color content fidelity ratio, E score and subjective evaluation. 相似文献
6.
Effect of replacement of fat with 25, 50, 75 and 100% sesame oil (on fat basis); 50% sesame oil, hydrocolloids and emulsifiers on the rheological, microstructural, quality characteristics and fatty acid profile of cake was studied. Addition of increasing amount of sesame oil decreased viscosity, increased specific gravity of cake batter; decreased cake volume and overall quality score. Microstructure studies showed disrupted gluten matrix. Among the two different hydrocolloids [hydroxypropylmethylcellulose (HPMC) and xanthan] and emulsifiers [glycerol monostearate (GMS) and sodium stearoyl-2-lactylate (SSL)] tried, HPMC and SSL increased the batter viscosity, decreased the specific gravity, increased the volume and overall quality score. Use of combination of HPMC and SSL improved significantly the quality characteristics of cake with 50% sesame oil in such a way that the overall quality score was higher than that of the control cake with fat. The microstructure of cake crumb with 50% sesame oil and HPMC showed a smooth structure with less number of cavities and SSL showed a continuous protein matrix. On replacing the fat with 50% sesame oil, there was a decrease in saturated fatty acids and increase in unsaturated fatty acids, particularly linoleic acid. The fatty acid profile of cake with 50% sesame oil was better than the control cake as there was 2.4 times decrease in palmitic acid content and 5.9 times increase in essential fatty acids (EFA) content. 相似文献
7.
P. Esakkiraj G. Immanuel S. M. Sowmya P. Iyapparaj A. Palavesam 《Food and Bioprocess Technology》2009,2(4):383-390
Extracellular protease production by Bacillus cereus isolated from the intestine of fish Mugil cephalus has been investigated in shake-flask experiment using different preparations of tuna-processing waste such as raw fish meat,
defatted fish meat, alkali hydrolysate, and acid hydrolysate as nitrogen source. Among the tuna preparations tested, defatted
fish meat supported the maximum protease production (134.57 ± 0.47 U ml−1), and 3% concentration of the same was found to be optimum for maximizing the protease production (178.50 ± 0.28 U ml−1). Effect of carbon sources on protease production in the optimized concentration of defatted tuna fish meat revealed that
galactose aided the higher protease production (259.83 ± 0.04 U ml–1) than the other tested carbon sources and a concentration of 1.5% galactose registered as optimum to enhance the protease
production (289.40 ± 0.16 U ml−1). The halotolerancy of B. cereus for protease production indicated that 3% of sodium chloride was optimum to yield maximum protease (301.63 ± 0.20 U ml−1). Among the surfactants tested, protease production was high in Triton X 100-added medium (298.63 ± 0.12 U ml−1) when compared to other surfactants, and its optimum concentration recorded was 0.8% (320.57 ± 0.17 U ml−1) for more protease production. Partial characterization of crude enzyme revealed that pH 7.0 (278.90 ± 0.08 U ml−1) and 60°C temperature (332.37 ± 0.18 U ml−1) were optimum for better protease activity by B. cereus. 相似文献
8.
Amorphous zinc oxide thin films are obtained by thermally evaporating pure zinc oxide powder. Films obtained have an excellent conductivity of 90 ???1 cm?1 with transparency of up to 90% in the visible region. On doping with gallium oxide a great improvement in the conductivity of up to 8.7 × 103 ???1 cm?1 is observed and the optical band gap of the films is decreased from 3.25 to 3.2 eV, retaining the transparency. Measurements of activation energy show that the doped ZnO film has one donor level at 68 meV and other at 26 meV bellow the conduction band. 相似文献
9.
In this work, a frequency-based dimensionality reduction technique using variational mode decomposition (VMD) is proposed. Dimensionality reduction is a very important aspect of preprocessing in case of hyperspectral image (HSI) analysis where this step helps in elimination of the lesser informative bands, thereby reducing the size of the data and making its processing computationally less challenging. In contrast to the standard dimensionality reduction methods such as inter-band block correlation (IBBC) where bands are eliminated based on their similarity with the consecutive bands, the proposed method uses frequency information of each band to categorize it as a less or more informative band. In this way, only the topmost informative bands of HSI are selected to form the reduced dataset. In our experiment, in order to verify the efficiency of VMD as a dimensionality reduction technique, the hyperspectral unmixed results obtained for IBBC reduced dataset is compared with those obtained for VMD reduced dataset. From the parametric measures such as classification accuracy, root-mean-square error (RMSE) and visual results obtained after unmixing for both IBBC and VMD reduced datasets, it is noticed that the VMD reduced dataset performs better by achieving higher classification accuracy and lower RMSE than that of the existing IBBC method. 相似文献
10.
This article discusses a model intelligence technique called proactive modeling. The goal of proactive modeling is to reduce the amount of manual modeling required when using a graphical DSML and to assist in step-by-step creation of a model. Proactive modeling accomplishes this goal by examining the metamodels syntax and constraints, automatically executing model modifications, and prompting the modeler for assistance when more than one valid model modification exists, but none are necessary. We have integrated proactive modeling into the generic modeling environment (GME) as a generic add-on that can operate on any domain-specific modeling language implemented in GME. Lastly, results from applying proactive modeling to several DSMLs in GME show that it can reduce modeling effort. 相似文献