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Effect of hydroalcoholic extract of aerial parts of Leucas aspera (Willd.) link on inflammatory markers in complete freund′s adjuvant induced arthritic rats
Kripa K,Chamundeeswari D,Thanka J,Reddy C
International Journal of Green Pharmacy , 2010,
Abstract: The plant Leucas aspera is claimed to possess anti-inflammatory and anti-rheumatic potential by traditional practitioners. The aim of this study is to validate the traditional claim. The hydroalcoholic extract of aerial parts of L. aspera (HAELA) was orally tested at a dose of 100 mg/kg bodyweight for anti-arthritic effect in adjuvant-induced arthritic rats. Group I rats served as vehicle control group [0.2% carboxyl methyl cellulose (CMC) p.o.]. The test groups were injected with 0.1 ml of complete Freund′s adjuvant into the subplantar region of right hind paw. Group II animals served as disease control, while the group III and group IV arthritic rats were treated with standard drug diclofenac sodium (0.3 mg/kg) and HAELA (100 mg/kg) for 21 days. Activities of inflammatory markers such as tumour necrosis factor-α, C-reactive protein, interleukin-2, cathepsin D and antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) were estimated in plasma/haemolysate and tissue of control and arthritic animals. Histopathological analysis of knee joints was also performed. Statistical analysis of the biochemical parameters was performed by one way analysis of variance (ANOVA) using SPSS software package. Results were expressed as mean±SEM for six rats in each group. P<0.05 was considered to be significant. HAELA showed significant anti-inflammatory (P<0.001) and antioxidant activity (P<0.001) at the specified dose. It did not show mortality up to 2000 mg/kg body weight. Histopathological studies confirmed cartilage regeneration and near normal joint in HAELA treated rats. It can thus be concluded that HAELA possesses significant antioxidant and anti-arthritic potential.
Comparative Analysis of Analog and Digital Controllers for Negative Output Superlift Luo Converter (NOSLC)  [PDF]
Chamundeeswari Vinayagam, Seyezhai Ramalingam
Circuits and Systems (CS) , 2016, DOI: 10.4236/cs.2016.78146
Abstract: This paper focuses on the comparative study of analog and digital control techniques for Negative Output Superlift Luo converter (NOSLC). NOSLC is a high gain converter in which the positive source voltage is converted into a negative load voltage. Though the negative load voltage is produced effectively, there is lot of non-linearities that affects the voltage level. To overcome this, analog controllers like Proportional-integral (PI), fuzzy PI and a sliding mode controller (SMC) were proposed for NOSLC. However PI controller does not respond to changes in operating point, fuzzy PI is based on the systematic approach and proved to be a trial and error oriented method and SMC brings an oscillation in the duty cycle. Therefore, to overcome these drawbacks, a digital control technique using PIC microcontroller is proposed in this paper which provides high versatility and programmability approach. Simulation studies are carried out in MATLAB and the performances of these controllers have been investigated for the proposed DC-DC converter. A prototype of the NOSLC converter is built by employing digital control and the results are verified experimentally.
An Approach towards Pulse Data Transmission Using Modified Negative Luo Converter (MNLC) for Telecoms  [PDF]
V. Chamundeeswari, Dr. R. Seyezhai
Circuits and Systems (CS) , 2016, DOI: 10.4236/cs.2016.79234
Abstract: Telecom sectors generally operate at negative voltages to reduce the effect of corrosion caused in the metallic wire due to electrochemical reaction while communicating signals. To feed those lines and to have an effective digital data transmission, a power electronic converter referred as Modified Negative Luo Converter (MNLC) is proposed in this paper. MNLC is a high gain converter in which the output voltage increases in geometric progression. This paper portrays a novel concept of a 50 Hz pulse data transmission throughRLCG (Resistance-inductance-capacitance with a shunt conductance) transmission line using MNLC. Signal frequency of 50 Hz to be transmitted is anded with a high frequency pulse that charges and discharges MNLC and produces the boosted negative output voltage. The boosted output is again transmitted through the RLCG transmission line from which 50 Hz data pulse is retrieved at the output of the transmission line by comparing with a comparator signal. This sort of MNLC aided data transmission not only introduces less loss in its transmitted data but also overcomes various health hazards of conventional radio frequency (RF) communication. This technique also proves that any data bit stream can be transmitted and retrieved using the proposed high gain DC-DC converter. The simulation model of the proposed system is implemented in MATLAB for various switching frequencies with its prototype of the converter developed and the results are verified.
Theoretical and experimental studies on 2-(2-methyl-5-nitro-1-imidazolyl)ethanol
Sirukarumbur Panduranga Vijaya Chamundeeswari,Emmanuel Rajan James Jebaseelan Samuel,Namadevan Sundaraganesan
European Journal of Chemistry , 2011, DOI: 10.5155/eurjchem.2.2.136-145.169
Abstract: In this work, we report a combined experimental and theoretical study on molecular structure, vibrational spectra, natural bond orbital (NBO) and UV spectral analysis of [2-(2-methyl-5-nitro-1-imidazolyl) ethanol] (Metronidazole-MTD). The FT-IR solid phase (4000-400 cm-1) liquid phase, and FT-Raman spectra (3500-50 cm-1) of MTD were recorded. The molecular geometry, harmonic vibrational frequencies and bonding features of MTD in the ground state have been calculated using the density functional method B3LYP with 6-311G(d,p) as basis set. The assignments of the vibrational spectra have been carried out with the help of the Gauss view program package. Stability of the molecule arising from hyperconjugative interactions and charge delocalization have been analyzed using natural bond orbital analysis. The results show that charge in electron density (ED) in the σ* and π* antibonding orbitals and second order stabilization energies E2 confirms the occurrence of Intramolecular Charge Transfer (ICT) within the molecule. The UV spectrum was measured in ethanol solution. The energy and oscillator strength calculated by Time-Dependent Density Functional Theory (TD-DFT) results complement the experimental findings. The calculated HOMO and LUMO energies show that charge transfer occurs within the molecule. The 1H and 13C nuclear magnetic resonance (NMR) chemical shifts of the molecule were calculated by the Gauge Independent Atomic Orbital (GIAO) method and compared with experimental results. Finally the results of calculations were applied to simulate Infrared and Raman spectra of the title compound which show good agreement with observed spectra.
Electrical Conductivity of Collapsed Multilayer Graphene Tubes  [PDF]
D. Mendoza
World Journal of Nano Science and Engineering (WJNSE) , 2012, DOI: 10.4236/wjnse.2012.22009
Abstract: Synthesis of multilayer graphene on copper wires by a chemical vapor deposition method is reported. After copper etching, the multilayer tube collapses forming stripes of graphitic films, their electrical conductance as a function of temperature indicate a semiconductor-like behavior. Using the multilayer graphene stripes, a cross junction is built and owing to its electrical behavior we propose that a tunneling process exists in the device.
Porous Carbon Grown by Chemical Vapor Deposition on Copper Substrates  [PDF]
D. Mendoza
Journal of Materials Science and Chemical Engineering (MSCE) , 2015, DOI: 10.4236/msce.2015.38003
Abstract: Amorphous porous carbon was synthesized by chemical vapor deposition on copper substrates. The average size of the pores is around 1.2 microns with some small pores decorating the big ones. Lamellar samples of this carbonaceous material can be separated from the copper support and may be useful as electrode due to its low electrical resistivity of the order of 0.4 Ωcm.
Application of Enzyme Extracted from Aloe vera Plant in Chemical Pretreatment of Cotton Knitted Textile to Reduce Pollution Load  [PDF]
D. Jothi
World Journal of Engineering and Technology (WJET) , 2015, DOI: 10.4236/wjet.2015.33B007
Abstract:

Nowadays, highly alkaline chemicals like caustic soda, soda ash, silicate, acetic acid and soaping agents are used for scouring to remove the non-cellulosic impurities from the cotton. Using 30 - 40 gm/Kg on weight of the fabric results in destruction of cotton structure. Intensive rinsing and more acid is needed for reutilization of cotton, which enlarges the volume of effluent. Furthermore, these hazards chemicals result in increase in COD, BOD and TDS in waste water. These chemicals also attack the cellulose leading to heavy strength loss and weight loss in the fabric. The net result is low quality control and polluted environment with high usage of energy, time, chemical and water. Aloe vera presents the finest commercial opportunity in various industrial sectors among the various plants. Also, most of the countries are gifted with the unique geographical features that are essential for cultivation of Aloe vera. Yet, none of the country has realized and reaped the full potential of such plants in various industrial applications. The reason is simple: lack of the requisite expertise in extraction of various enzymes present in aloe plant. Fortunately, the technology is now accessible to make use of enzyme in textile application. In this research an attempt has been made to make use of lipase enzyme extracted from aloe plant in textile chemical pre- treatment process. In the present research work, an attempt was made to develop bio scouring of 100% cotton knitted fabric with lipase enzyme extracted from Aloe deberena plant at various concentration (1%, 2% and 3%) at various temperature (40?C, 60?C and 70?C) for a period of 30 minutes, 60 minutes and 90 minutes. The properties of bio scoured fabrics are compared with these of conventional scoured one. Encouraging results in terms of dye uptake, dye levelness, wash fastness, light fastness and rubbing fastness are obtained in case of bio scouring fabric dyed with dark reactive colors. Further, it reduces volume of effluent as well as COD, TDS and pH. It saves a substantial thermal energy 50% and electrical energy 40%. Bio scouring waste water has 40% - 50% less COD and 60% less TDS as compared to conventional scouring waste water.

Hyporheic Zone Hydrochemistry of the Mine-Polluted River  [PDF]
D. Ciszewski
Journal of Geoscience and Environment Protection (GEP) , 2015, DOI: 10.4236/gep.2015.310008
Abstract:

Intensity of stream waters mixing with groundwaters and lateral extent of these processes in the hyporheic zone were investigated in a near-bank sandbar and an adjacent floodplain through the comparison of groundwaters and stream water chemistry of the Bia?a Przemsza River in southern Poland. The stream waters were polluted by the discharge of mine waters from “Boles?aw” lead and zinc mine. The investigated waters were several times more mineralized than the natural spring waters of the river valley. The concentration of: potassium, sodium, and the pH, as well as cadmium, lead, and zinc decreased in the hyporheic zone towards the stream bank, whereas conductance, calcium, magnesium, sulphates, as well as silica contents were the highest on the floodplain, diminishing towards the stream. The changes observed in the chemical composition of groundwaters were apparent in mixing stream waters below the depth of 2 m with shallow groundwaters draining the valley slope. Hyporheic mixing also takes place in the 10-meter-wide, marginal zone of the sandbar, whereas in the 5-meter-wide stream-side zone of the sandbar groundwaters represent weakly transformed stream water.

Fractional Topological Insulators—A Bosonization Approach  [PDF]
D. Schmeltzer
Journal of Modern Physics (JMP) , 2016, DOI: 10.4236/jmp.2016.71012
Abstract: A metallic disk with strong spin orbit interaction is investigated. The finite disk geometry introduces a confining potential. Due to the strong spin-orbit interaction and confining potential the metal disk is described by an effective one-dimensional model with a harmonic potential. The harmonic potential gives rise to classical turning points. As a result, open boundary conditions must be used. We bosonize the model and obtain chiral Bosons for each spin on the edge of the disk. When the filling fraction is reduced to \"\" the electron-electron interactions are studied by using the Jordan Wigner phase for composite fermions which give rise to a Luttinger liquid. When the metallic disk is in the proximity with a superconductor, a Fractional Topological Insulator is obtained. An experimental realization is proposed. We show that by tunning the chemical potential we control the classical turning points for which a Fractional Topological Insulator is realized.
Utilizing Dimensional Analysis with Observed Data to Determine the Significance of Hydrodynamic Solutions in Coastal Hydrology  [PDF]
Eric D. Swain, Jeremy D. Decker, Joseph D. Hughes
Computational Water, Energy, and Environmental Engineering (CWEEE) , 2014, DOI: 10.4236/cweee.2014.32008
Abstract:

In this paper, the authors present an analysis of the magnitude of the temporal and spatial acceleration (inertial) terms in the surface-water flow equations and determine the conditions under which these inertial terms have sufficient magnitude to be required in the computations. Data from two South Florida field sites are examined and the relative magnitudes of temporal acceleration, spatial acceleration, and the gravity and friction terms are compared. Parameters are derived by using dimensionless numbers and applied to quantify the significance of the hydrodynamic effects. The time series of the ratio of the inertial and gravity terms from field sites are presented and compared with both a simplified indicator parameter and a more complex parameter called the Hydrodynamic Significance Number (HSN). Two test-case models were developed by using the SWIFT2D hydrodynamic simulator to examine flow behavior with and without the inertial terms and compute the HSN. The first model represented one of the previously-mentioned field sites during gate operations of a structure-managed coastal canal. The second model was a synthetic test case illustrating the drainage of water down a sloped surface from an initial stage while under constant flow. The analyses indicate that the times of substantial hydrodynamic effects are sporadic but significant. The simplified indicator parameter correlates much better with the hydrodynamic effect magnitude for a constant width channel such as Miami Canal than at the non-uniform North River. Higher HSN values indicate flow situations where the inertial terms are large and need to be taken into account.

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