FORMULATION AND EVALUATION OF SUSTAINED RELEASE MATRIX TABLETS OF LEVOSULPIRIDE BY USING NATURAL POLYMER

Objective: The objective of the present study was to develop sustained release matrix tablets of levosulpiride by using natural polymers.Method: The tablets were prepared with different ratios of Chitosan, Xanthan gum and Guar gum by wet granulation technique. The solubility study of the levosulpiride was conducted to select a suitable dissolution media for in vitro drug release studies.Results: Fourier transform infrared (FTIR) study revealed no considerable changes in IR peak of levosulpiride and hence no interaction between drug and the excipients. DSC thermograms showed that no drug interaction occurred during the manufacturing process. In vitro dissolution study was carried out for all the formulation and the results compared with marketed sustained release tablet. The drug release from matrix tablets was found to decrease with increase in polymer ratio of Chitosan, Xanthan gum and Guar gum.Conclusion: Formulation LF3 exhibited almost similar drug release profile in dissolution media as that of marketed tablets. From the results of dissolution data fitted to various drug release kinetic equations, it was observed that highest correlation was found for First order, Higuchi's and Korsmeyer equation, which indicate that the drug release occurred via diffusion mechanism.    Â

Spherically Symmetric Analytic Solutions and Naked Singularities in Einstein-Aether Theory

In the present work we analyze all the possible spherically symmetric exterior vacuum solutions allowed by the Einstein-Aether theory with static aether. We show that there are four classes of solutions corresponding to different values of a combination of the free parameters, $c_{14}=c_1+c_4$, which are: $0 < c_{14}<2$, $c_{14} < 0$, $c_{14}=2$ and $c_{14}=0$. We present explicit analytical solutions for $c_{14}=3/2, 16/9, 48/25, -16, 2$ and $0$. The first case has some pathological behavior, while the rest have all singularities at $r=0$ and are asymptotically flat spacetimes. For the solutions $c_{14}=16/9, 48/25\, \mathrm{\, and \,}\, -16$ we show that there exist no horizons, neither Killing nor universal horizon, thus we have naked singularities. Finally, the solution for $c_{14}=2$ has a metric component as an arbitrary function of radial coordinate, when it is chosen to be the same as in the Schwarzschild case, we have a physical singularity at finite radius, besides the one at $r=0$. This characteristic is completely different from General Relativity.Comment: 21 pages and 9 figure

Cylindrical Gravitational Waves in Einstein-Aether Theory

Along the lines of the Einstein-Rosen wave equation of General Relativity (GR), we derive a gravitational wave equation with cylindrical symmetry in the Einstein-aether (EA) theory. We show that the gravitational wave in the EA is periodic in time for both the metric functions $\Psi(r,t)$ and $H(r,t)$. However, in GR, $\Psi(r,t)$ is periodic in time, but $H(r,t)$ is semi-periodic in time, having a secular drifting in the wave frequency. The evolution of wave pulses of a given width is entirely different in both theories in the $H(r,t)$ metric function due to this frequency drifting. Another fundamental difference between the two theories is the gravitational wave velocity. While in GR, the waves propagate with the speed of light, in EA, there is no upper limit to the wave velocity, reaching infinity if $c_{13} \rightarrow 1$ and zero if $c_{13} \rightarrow -\infty$. We also show that energy-momentum pseudotensor and superpotential get contributions from aether in addition to the usual gravitational field part. All these characteristics are observational signatures that differentiate GR and EA.Comment: 26 pages, 10 figures. We have corrected the initial conditions for $H(r,t)$ in order to have $\Psi(r,t)$ not equal to $H(r,t)

Structural and Electrical Studies of Boric Acid Doped Cadmium Oxide Thin Film by JNSP Technique for Optoelectronic Applications

The present work deals with preparation and characterization of boric acid (b) dopped cdo thin films by the jet nebulizer spray pyrolysis technique at optimized temperature 450°C. Boric acid doped cdo thin films were prepared by jet nebulizer spray pyrolysis technique with different wt% of boric acid (x=0, 0.5,2.5, 4). The xrd pattern of various weight percentage boric acid dopped cdo thin films show the polycrystalline nature with cubic structure. At room temperature, the electrical conductivity of the prepared films increases with 4Wt% of 2.32x10-3 S/cm. The plot of voltage versus current as a function of temperature (RT-30°C) indicates the ohmic behavior of the films. Moreover, significant optoelectronic applications are cadmium oxide dopped with boric acid thin films at room temperature electrical resistivity is in the order of 101Ω cm which is low enough to be a good supercapacitor electrode material

Did mangroves offer an effective barrier to the Thane cyclone surges?

Mangrove ecosystems support vital wetland communities of plants and animals. They are characterized by unique species of trees and shrubs that fringe the intertidal zone along sheltered coastal, estuarine and riverine areas in tropical and subtropical latitudes. Mangroves have played an important role in the economy of our coastal population for thousands of years, providing a variety of goods and services, including wood production, support for commercial and subsistence fisheries, aquaculture, salt production, and coastal erosion control

Bounds on large extra dimensions from photon fusion process in SN1987A

The constraint on the ADD model of extra dimensions coming from photon annihilation into Kaluza-Klein graviton in supernova cores is revisited. In the two photon process for a conservative choice of the core parameters, we obtain the bound on the fundamental Planck scale $M_* \gtrsim$ 1.6 TeV. The combined energy loss rate due to nucleon-nucleon brehmstrahlung and photon annihilation processes is rederived, which shows that the combined bounds add only second decimal place to $M_*$. The present study can strengthen the results that are available in the current literature for the graviton emission from SN1987A which puts a very strong constraints on models with large extra dimensions for the case of $n=3$ .Comment: To appear in JCA

Biology, Fishery, Conservation and Management of Indian Ocean Tuna Fisheries

The focus of the study is to explore the recent trend of the world tuna fishery with special reference to the Indian Ocean tuna fisheries and its conservation and sustainable management. In the Indian Ocean, tuna catches have increased rapidly from about 179959 t in 1980 to about 832246 t in 1995. They have continued to increase up to 2005; the catch that year was 1201465 t, forming about 26% of the world catch. Since 2006 onwards there has been a decline in the volume of catches and in 2008 the catch was only 913625 t. The Principal species caught in the Indian Ocean are skipjack and yellowfin. Western Indian Ocean contributed 78.2% and eastern Indian Ocean 21.8% of the total tuna production from the Indian Ocean. The Indian Ocean stock is currently overfished and IOTC has made some recommendations for management regulations aimed at sustaining the tuna stock. Fishing operations can cause ecological impacts of different types: by catches, damage of the habitat, mortalities caused by lost or discarded gear, pollution, generation of marine debris, etc. Periodic reassessment of the tuna potential is also required with adequate inputs from exploratory surveys as well as commercial landings and this may prevent any unsustainable trends in the development of the tuna fishing industry in the Indian Ocean