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Pune, India

The Savitribai Phule Pune University , is a university located in western India, in the city of Pune. It was founded in 1948 and is one of India's premier Universities. Spread over a 411 acres campus, the university is home to 46 academic departments. The university has been given the highest "A" rating by the National Assessment and Accreditation Council for its overall performance.The university has numerous affiliated colleges, departments, and research institutes, which are primarily located in Pune. Wikipedia.

The removal of hexavalent chromium [Cr (VI)], an important ground water pollutant by phyto-inspired Fe(0)/Fe(3)O(4) nanocomposite-modified cells of Yarrowia lipolytica (NCIM 3589 and NCIM 3590), was investigated. Electron microscopy and magnetometer studies indicated an effective modification of yeast cell surfaces by the nanocomposites. The effect of pH, temperature, agitation speed, contact time and initial metal ion concentration on the removal of Cr (VI) was determined. The specific uptake values at pH 2.0 were 186.32±3.17 and 137.31±4.53 mg g(-1) for NCIM 3589 and NCIM 3590, respectively, when 1000 mg L(-1) of metal ion concentrations were used. The equilibrium data fitted to Scatchard, Langmuir and linearized Freundlich models suggesting that adsorption played a role in the removal of Cr (VI) ions. The surface modified yeast cells displayed higher values of Langmuir and Scatchard coefficients than the unmodified cells indicating that the former were more efficient in Cr (VI) removal. The enhanced detoxification of Cr (VI) ions by this composite material could be attributed to the reductive power of the Fe(0)/Fe(3)O(4) nanocomposites as well the yeast cell surface functional groups. Copyright © 2012 Elsevier B.V. All rights reserved. Source

Padmanabhan T.,University of Pune
Modern Physics Letters A | Year: 2010

It is possible to provide a physical interpretation for the field equations of gravity based on a thermodynamical perspective. The virtual degrees of freedom associated with the horizons, as perceived by the local Rindler observer, play a crucial role in this approach. In this context, the relation S = E/2T between the entropy (S), active gravitational mass (E) and temperature (T) obtained previously in gr-qc/0308070 [CQG, 21, 4485 (2004)] can be reinterpreted as the law of equipartition E = (1/2) nkBT where n=Δ A/LP2 is the number (density) of microscopic horizon degrees of freedom in an area A. Conversely, one can use the equipartition argument to provide a thermodynamic interpretation of gravity, even in the nonrelativistic limit. These results emphasize the intrinsic quantum nature of all gravitational phenomena and diminishes the distinction between thermal phenomena associated with local Rindler horizons and the usual thermodynamics of macroscopic bodies in non-inertial frames. Just like the original thermodynamic interpretation, these results also hold for a wide class of gravitational theories like the LanczosLovelock models. © 2010 World Scientific Publishing Company. Source

Padmanabhan T.,University of Pune
General Relativity and Gravitation | Year: 2014

I show that the gravitational dynamics in a bulk region of space can be connected to a thermodynamic description in the boundary of that region, thereby providing clear physical interpretations of several mathematical features of classical general relativity: (1) The Noether charge contained in a bulk region, associated with a specific time evolution vector field, has a direct thermodynamic interpretation as the gravitational heat content of the boundary surface. (2) This result, in turn, shows that all static spacetimes maintain holographic equipartition in the following sense: In these spacetimes, the number of degrees of freedom in the boundary is equal to the number of degrees of freedom in the bulk. (3) In a general, evolving spacetime, the rate of change of gravitational momentum is related to the difference between the number of bulk and boundary degrees of freedom. It is this departure from the holographic equipartition which drives the time evolution of the spacetime. (4) When the equations of motion hold, the (naturally defined) total energy of the gravity plus matter within a bulk region, will be equal to the boundary heat content. (5) After motivating the need for an alternate description of gravity (if we have to solve the cosmological constant problem), I describe a thermodynamic variational principle based on null surfaces to achieve this goal. The concept of gravitational heat density of the null surfaces arises naturally from the Noether charge associated with the null congruence. The variational principle, in fact, extremises the total heat content of the matter plus gravity system. Several variations on this theme and implications are described. © 2014 Springer Science+Business Media New York. Source

Padhye S.,University of Pune
Mini reviews in medicinal chemistry | Year: 2010

Curcumin is a natural polyphenol derived from the plant Curcuma longa, commonly called turmeric. Extensive research over past 50 years has indicated that this polyphenol is highly pleiotropic molecule capable of preventing and treating various cancers. The anticancer potential of Curcumin is severely affected by its limited systemic and target tissue bioavailability and rapid metabolism. In the present review article, we provide a summarized account of different drug delivery systems employed for tackling the problem of cucumin's bioavailability such as liposomes, phospholipid complexes and nanoparticles. Concomitantly we have reviewed the large volume of literature reports describing structural modifications of Curcumin and the anticancer potential of its analogs. Some of the difluorocurcumin analogs allowing longer circulation times and preferential accumulation in the pancreas seem to offer promising leads for conducting first in-depth animal studies and subsequently clinical trials for the use of these analogs for prevention of tumor progression and/or treatments of human malignancies. Source

Padmanabhan T.,University of Pune
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2010

I show that the principle of equipartition, applied to area elements of a surface ∂ V which are in equilibrium at the local Davies-Unruh temperature, allows one to determine the surface number density of the microscopic spacetime degrees of freedom in any diffeomorphism invariant theory of gravity. The entropy associated with these degrees of freedom matches with the Wald entropy for the theory. This result also allows one to attribute an entropy density to the spacetime in a natural manner. The field equations of the theory can then be obtained by extremizing this entropy. Moreover, when the microscopic degrees of freedom are in local thermal equilibrium, the spacetime entropy of a bulk region resides on its boundary. © 2010 The American Physical Society. Source

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