Narasimham Committee Report - Some Further Ramifications and Suggestions

This paper while agreeing with the general thrust of the Narasimham Committee Report. Calls attention to some logical corollaries of the Report and analyses some possible fallout from implementing the Report. We agree with the view that control of banking system should be under an autonomous body supervised by the RBI. However at the level of individual banks, closer scrutiny of lending procedures may be called for than is envisaged in the Report. In a freely functioning capital market the potential of government bonds is enormous, but this necessitates restructuring of the government bond market. The government bonds may then also be used as suitable hedging mechanisms by introducing options and futures trading. We recommend freeing up the operation of pension and provident fund to enable at least partial investment of such funds in risky securities. In the corporate sector, we believe that the current 2:1 debt equity norm is too high and not sustainable in the long term. We envisage that high debt levels and higher interest rates, combined with higher business risk may result in greater incidence of corporate sickness. This may call for various schemes for retrenched workers and amendment to land laws for easy exit of companies. On account of interdependencies across different policies, any sequencing of their implementation may be highly problematic. We therefore suggest a near simultaneity in the implementation of various reforms in order to build up a momentum which would be irreversible if people are to have confidence that the reforms will endure, and if we are to retain our credibility with international financial institutions.

Protective effect of ethanolic leaf extract of Alphonsea sclerocarpa against ethylene glycol induced urolithiasis in rats

252-258Alphonsea sclerocarpa Thwaites belonging to the family Annonaceae is a small tree, which grows up to 10-15 m tall the leaves are simple and alternate. Despite its medicinal properties the plant seems to be less explored and hence this research aims at exploring the antiurolithiatic activity of ethanolic leaf extract of A. sclerocarpa on ethylene glycol induced urolithiasis in rats. A. sclerocarpa leaf powder was extracted using ethanol. The effect of ethanolic leaf extract of A. sclerocarpa (250 and 500 mg/kg, p.o.) was studied in experimentally induced renal stone in rats by in vivo model. Ethylene glycol model (0.75% in drinking water, for 28 days) was used for renal stone induction. The blood, urine and kidney samples were used for various parameters. The concentration of calcium, oxalate, phosphorus, creatinine and blood urea nitrogen was observed in each group. The phytochemical analysis was carried out to detect the presence of secondary metabolites like saponins and flavonoids in the ethanolic extract of A. sclerocarpa leaf extract. In ethylene glycol (0.75% v/v) treated animal model ethanolic extract of A. sclerocarpa leaf extract showed significant results on stone promoters (calcium oxalate, inorganic phosphate and sodium), kidney function parameters (uric acid, blood urea nitrogen, creatinine). On the basis of biochemical parameters and histopathological study it was confirmed that A. sclerocarpa leaf extract protected the renal cells from oxidative stress and injury induce by calcium oxalate crystals. The investigation of ethanolic extract of A. sclerocarpa leaf has shown promising antiurolithiatic activity and support folklore claims of these plants as antiurolithiatic. The mechanism of action of these plants for antiurolithiatic is apparently related to increased diuresis and lowering of urinary concentrations of stone-forming constituents, though it should be confirmed by the extensive exploratory studies

What determines the spectrum of protein native state structures

AbstractWe present a brief summary of the key factors underlying protein structure, as developed in the investigations of Pauling, Ramachandran, and Rose. We then outline a simplified physical model of proteins that focusses on geometry and symmetry. Although this model superficially appears unrelated to the detailed chemical descriptions commonly applied to proteins, we show that it captures the essential elements of the chemistry and provides a unified framework for understanding the common characteristics of folded proteins. We suggest that the spectrum of protein native state structures is determined by geometry and symmetry and the role of the sequence is to choose its native state structure from this predetermined menu. Proteins 2006. © 2006 Wiley‐Liss, Inc

Nanoscale fluid flows in the vicinity of patterned surfaces

Molecular dynamics simulations of dense and rarefied fluids comprising small chain molecules in chemically patterned nano-channels predict a novel switching from Poiseuille to plug flow along the channel. We also demonstrate behavior akin to the lotus effect for a nanodrop on a chemically patterned substrate. Our results show that one can control and exploit the behavior of fluids at the nanoscale using chemical patterning.Comment: Phys. Rev. Lett. in pres

Spatial Scaling in Model Plant Communities

We present an analytically tractable variant of the voter model that provides a quantitatively accurate description of beta-diversity (two-point correlation function) in two tropical forests. The model exhibits novel scaling behavior that leads to links between ecological measures such as relative species abundance and the species area relationship.Comment: 10 pages, 3 figure

Diffusion, peer pressure and tailed distributions

We present a general, physically motivated non-linear and non-local advection equation in which the diffusion of interacting random walkers competes with a local drift arising from a kind of peer pressure. We show, using a mapping to an integrable dynamical system, that on varying a parameter, the steady state behaviour undergoes a transition from the standard diffusive behavior to a localized stationary state characterized by a tailed distribution. Finally, we show that recent empirical laws on economic growth can be explained as a collective phenomenon due to peer pressure interaction.Comment: RevTex: 4 pages + 3 eps-figures. Minor Revision and figure 3 replaced. To appear in Phys. Rev. Letter

Evaluating the accuracy of Gaussian approximations in VSWIR imaging spectroscopy retrievals

The joint retrieval of surface reflectances and atmospheric parameters in VSWIR imaging spectroscopy is a computationally challenging high-dimensional problem. Using NASA's Surface Biology and Geology mission as the motivational context, the uncertainty associated with the retrievals is crucial for further application of the retrieved results for environmental applications. Although Markov chain Monte Carlo (MCMC) is a Bayesian method ideal for uncertainty quantification, the full-dimensional implementation of MCMC for the retrieval is computationally intractable. In this work, we developed a block Metropolis MCMC algorithm for the high-dimensional VSWIR surface reflectance retrieval that leverages the structure of the forward radiative transfer model to enable tractable fully Bayesian computation. We use the posterior distribution from this MCMC algorithm to assess the limitations of optimal estimation, the state-of-the-art Bayesian algorithm in operational retrievals which is more computationally efficient but uses a Gaussian approximation to characterize the posterior. Analyzing the differences in the posterior computed by each method, the MCMC algorithm was shown to give more physically sensible results and reveals the non-Gaussian structure of the posterior, specifically in the atmospheric aerosol optical depth parameter and the low-wavelength surface reflectances

Organization of Ecosystems in the Vicinity of a Novel Phase Transition

It is shown that an ecosystem in equilibrium is generally organized in a state which is poised in the vicinity of a novel phase transition.Comment: 4 pages, 2 figure

Boundary conditions at a fluid - solid interface

We study the boundary conditions at a fluid-solid interface using molecular dynamics simulations covering a broad range of fluid-solid interactions and fluid densities, and both simple and chain-molecule fluids. The slip length is shown to be independent of the type of flow, but rather is related to the fluid organization near the solid, as governed by the fluid-solid molecular interactions.Comment: REVtex, to appear in Physical Review Letter

Extensional rupture of model non-Newtonian fluid filaments

We present molecular dynamics computer simulations of filaments of model non-Newtonian liquid stretched in a uniaxial deformation to the point of breaking. The liquid consists of Lennard-Jones monomers bound into chains of 100 monomers by nonlinear springs, and several different constant velocity and constant strain rate deformations are considered. Generally we observe nonuniform extensions originating in an interplay between the stretching forces and elastic and capillary restoring mechanisms, leading to highly uneven shapes and alternating stretched and unstretched regions of liquid. Except at the fastest pulling speeds, the filaments continue to thin indefinitely and break only when depleted of molecules, rather than common viscoelastic rupture mechanisms.Comment: 7 pages text, 14 pages (eps) figure