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OALib Journal期刊

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Salinity Variations over Zhejiang Province Waters, China  [PDF]
Xiaohui Zhao, Feng Gui, Venkata Subrahmanyam Mantravadi, Liuzhu Wang
Open Access Library Journal (OALib Journal) , 2018, DOI: 10.4236/oalib.1104562
Abstract:
In this article, we analyzed the monthly, seasonal and annual salinity variations and their relations with sea surface temperature (SST), rainfall over the Zhejiang province from 2005 to 2017. SST and rainfall were chosen as the main influence factors. There is an inverse relationship between rainfall and salinity. And the SST has a positive relation with salinity, showing slightly seasonal difference. The vertical variation is checked from surface to 150 meter depth, and 50 m is suggested to be a separating layer for salinity variations. We found that monthly changes in salinity are more variable in seawater at different depths. Seasonal changes in salinity in this area are significant. In winter and spring, the temperature is low, evaporation is small, and there is little rainfall, resulting in relatively higher salinity; frequent typhoon in summer and autumn with a large amount of freshwater input from the Yangtze River causes a lower salinity. For annual changes, we found an increasing trend over the surface as well as in sub-surface. In addition, we found initially that the stratification of the saline waters in Zhejiang Province makes the sub-surface salinity higher.
Photocatalytic Degradation of Isoproturon Pesticide on C, N and S Doped TiO2  [PDF]
Police Anil Kumar Reddy, Pulagurla Venkata Laxma Reddy, Vutukuri Maitrey Sharma, Basavaraju Srinivas, Valluri Durga Kumari, Machiraju Subrahmanyam
Journal of Water Resource and Protection (JWARP) , 2010, DOI: 10.4236/jwarp.2010.23027
Abstract: TiO2 doped with C, N and S (TCNS photocatalyst) was prepared by hydrolysis process using titanium iso-propoxide and thiourea. The prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photo electron spectroscopy (XPS), BET surface area, FTIR and diffuse reflectance spectra (DRS). The results showed that the prepared catalysts are anatase type and nanosized par-ticles. The catalysts exhibited stronger absorption in the visible light region with a red shift in the adsorption edge. The photocatalytic activity of TCNS photocatalysts was evaluated by the photocatalytic degradation of isoproturon pesticide in aqueous solution. In the present study the maximum activity was achieved for TCNS5 catalyst at neutral pH with 1 g L-1 catalyst amount and at 1.14 x 10-4 M concentration of the pesticide solution. The TCNS photocatalysts showed higher phtocatalytic activity under solar light irradiation. This is attributed to the synergetic effects of red shift in the absorption edge, higher surface area and the inhibition of charge carrier recombination process.
Application of Experimental Design in Preparation of Nanoliposomes Containing Hyaluronidase
Narayanan Kasinathan,Subrahmanyam? Mallikarjuna Volety?,Venkata Rao Josyula?
Journal of Drug Delivery , 2014, DOI: 10.1155/2014/948650
Abstract: Hyaluronidase is an enzyme that catalyzes breakdown of hyaluronic acid. This property is utilized for hypodermoclysis and for treating extravasation injury. Hyaluronidase is further studied for possible application as an adjuvant for increasing the efficacy of other drugs. Development of suitable carrier system for hyaluronidase would help in coadministration of other drugs. In the present study, the hyaluronidase was encapsulated in liposomes. The effect of variables, namely, phosphatidylcholine (PC), cholesterol, temperature during film formation (T1), and speed of rotation of the flask during film formation (SPR) on percentage of protein encapsulation, was first analyzed using factorial design. The study showed that level of phosphatidylcholine had the maximum effect on the outcome. The effect of interaction of PC and SPR required for preparation of nanoliposomes was identified by central composite design (CCD). The dependent variables were percentage protein encapsulation, particle size, and zeta potential. The study showed that ideal conditions for production of hyaluronidase loaded nanoliposomes are PC—140?mg and cholesterol 1/5th of PC when the SPR is 150?rpm and T1 is 50°C. 1. Introduction Hyaluronic acid (HA) is a polysaccharide containing alternating units of glucuronic acid and glucosamine [1]. HA is distributed in tissues and is particularly abundant in extracellular matrices. Apart from the cellular and molecular functions, HA protects local tissues and cells against compression. HA, because of its high swelling property and viscous nature, restricts the movement of molecules including pharmacological agents across the tissues [2]. Hyaluronidase is an enzyme that catalyzes breakdown of HA. Approved label use of hyaluronidase includes treatment of extravasation injury, for hypodermoclysis and urography. Of late, hyaluronidase is tested for management of secondary complications associated with plastic surgery [3] and as an adjunct in improving the efficacy of pharmacological agents [4]. Use of hyaluronidase as an adjuvant therapy for improving the pharmacokinetic properties of coadministered drug is of particular interest as many of the regulatory bodies including US FDA have approved its use in humans [5]. The potential use of hyaluronidase as an adjunct could be exploited if a suitable carrier based delivery system for hyaluronidase is developed. This would allow coadministration of a second drug by directly incorporating them in the same delivery system and administering both drugs as a single dosage form. Few studies demonstrated that the
Quenching of fluorescence of aromatic molecules by graphene due to electron transfer
H S S Ramakrishna Matte,K S Subrahmanyam,K Venkata Rao,Subi J George,C. N. R. Rao
Physics , 2010,
Abstract: Investigations on the fluorescence quenching of graphene have been carried out with two organic donor molecules, pyrene butanaoic acid succinimidyl ester (PyBS, I) and oligo(p-phenylenevinylene) methyl ester (OPV-ester, II). Absorption and photoluminescence spectra of I and II recorded in mixture with increasing the concentrations of graphene showed no change in the former, but remarkable quenching of fluorescence. The property of graphene to quench fluorescence of these aromatic molecules is shown to be associated with photo-induced electron transfer, on the basis of fluorescence decay and time-resolved transient absorption spectroscopic measurements.
In vitro anticancer activity of microbial isolates from diverse habitats
Thomas, Angel Treasa;Rao, Josyula Venkata;Subrahmanyam, Volety Mallikarjuna;Chandrashekhar, Hariharapura Raghu;Maliyakkal, Naseer;Kisan, Tukaram Kedar;Joseph, Alex;Udupa, Nayanabhirama;
Brazilian Journal of Pharmaceutical Sciences , 2011, DOI: 10.1590/S1984-82502011000200009
Abstract: extracts from natural products, especially microorganisms, have served as a valuable source of diverse molecules in many drug discovery efforts and led to the discovery of several important drugs. identification of microbial strains having promising biological activities and purifying the bio-molecules responsible for the activities, have led to the discovery of many bioactive molecules. extracellular, as well as intracellular, extracts of the metabolites of thirty-six bacterial and twenty-four fungal isolates, grown under unusual conditions such as high temperature, high salt and low sugar concentrations, were in vitro tested for their cytotoxic potential on various cancer cell lines. the extracts were screened on hela and mcf-7 cell lines to study the cytotoxic potential. nuclear staining and flow cytometric studies were carried out to assess the potential of the extracts in arresting the cell cycle. the crude ethylacetate extract of isolate f-21 showed promising results by mtt assay with ic50 as low as 20.37±0.36 μg/ml on hela, and 44.75±0.81 μg/ml on mcf-7 cells, comparable with cisplatin. the isolate f-21 was identified as aspergillus sp. promising results were also obtained with b-2c and b-4e strains. morphological studies, biochemical tests and preliminary chemical investigation of the extracts were also carried out.
High-Fidelity Aerothermal Engineering Analysis for Planetary Probes Using DOTNET Framework and OLAP Cubes Database
Prabhakar Subrahmanyam
International Journal of Aerospace Engineering , 2009, DOI: 10.1155/2009/326102
Abstract: This publication presents the architecture integration and implementation of various modules in Sparta framework. Sparta is a trajectory engine that is hooked to an Online Analytical Processing (OLAP) database for Multi-dimensional analysis capability. OLAP is an Online Analytical Processing database that has a comprehensive list of atmospheric entry probes and their vehicle dimensions, trajectory data, aero-thermal data and material properties like Carbon, Silicon and Carbon-Phenolic based Ablators. An approach is presented for dynamic TPS design. OLAP has the capability to run in one simulation several different trajectory conditions and the output is stored back into the database and can be queried for appropriate trajectory type. An OLAP simulation can be setup by spawning individual threads to run for three types of trajectory: Nominal, Undershoot and Overshoot trajectory. Sparta graphical user interface provides capabilities to choose from a list of flight vehicles or enter trajectory and geometry information of a vehicle in design. DOTNET framework acts as a middleware layer between the trajectory engine and the user interface and also between the web user interface and the OLAP database. Trajectory output can be obtained in TecPlot format, Excel output or in a KML (Keyhole Markup Language) format. Framework employs an API (application programming interface) to convert trajectory data into a formatted KML file that is used by Google Earth for simulating Earth-entry fly-by visualizations.
Honey dressing for burns
Subrahmanyam M
Indian Journal of Plastic Surgery , 2010,
Abstract:
Impact of Wind Energy Modeled Distributed Generation on Reconfiguration of Unbalanced Radial Distribution System
JBV Subrahmanyam
Research Journal of Applied Sciences, Engineering and Technology , 2010,
Abstract: The aim of the study is to investigate the impact of wind energy modeled distributed generation on reconfiguration of unbalanced radial distribution system for voltage profile improvement and power loss minimization. By installing Distributed Generators (DG), reliability and voltage profile of unbalanced radial power distribution system can be improved with reduction of power losses. Unbalanced radial power distribution systems usually cause low power quality, low voltage profile, more investment and high operating costs. Feeder reconfiguration is a good technique to balance these systems to improve voltage profile and to reduce the power losses. In this paper a 0-1 integer programming optimization method for reconfiguration of unbalanced radial distribution system with wind energy modeled distributed generation, for improvement of voltage profile and power loss minimization is proposed. The results obtained with the proposed methodology for a practical system demonstrates its applicability.
Gobal entanglement and double occupancy in many-electron states
V. Subrahmanyam
Physics , 2009, DOI: 10.1016/j.physleta.2010.05.060
Abstract: The entanglement in many-electron states is investigated using a global entanglement measure, viz. average site mixedness. We have examined metallic states of noninteracting electrons, Nagaoka and Gutzwiller states of strongly-correlated electrons, and superconducting states. Uncorrelated metallic states at half filling seem to maximize entanglement, as these states optimize the number of holes, the number of doubly-occupied sites. Entanglement is calculated explicitly for Gutzwiller-projected many-electron states in one dimension, which have less entanglement as double occupancy is inhibited in these states. Entanglement in superconducting states, which tend to promote double occupancy, is calculated as a function of the energy gap, and found to be lower than the metallic state entanglement. There is a possibility of a regime with a nonzero single-site concurrence depending on the energy gap.
Domain wall dynamics of the Ising chains in a transverse field
V. Subrahmanyam
Physics , 2003, DOI: 10.1103/PhysRevB.68.212407
Abstract: We show that the dynamics of an Ising spin chain in a transverse field conserves the number of domains (strings of down spins in an up-spin background) at discrete times. This enables the determination of the eigenfunctions of the time-evolution operator, and the dynamics of initial states with domains. The transverse magnetization is shown to be identically zero in all sectors with a fixed number of domains. For an initial state with a single string of down spins, the local magnetization, the equal-time and double-time spin-spin correlation functions, are calculated analytically as functions of time and the initial string size. The domain size distribution function can be expressed as a simple integral involving Bessel functions.
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