A New Ecological RP-HPLC Method for the Determination of Pitavastatin,Fenofibrate and Their Impurities in a Novel Fixed Dose Combination

Chromatographia - We developed a simple, rapid, ecological RP-HPLC method for the estimation of Pitavastatin (PIT), Fenofibrate (FEN), and their impurities in a novel fixed dose combination. We...     

A Newman-Penrose-type formalism for space-times with torsion

The familiar Newman-Penrose formalism, in which the curvature of space-time is represented in terms of spin coefficients, is here extended to include the possibility of an asymmetric connection. It is hoped that this approach will be useful in dealing with certain problems in Einstein-Cartan theory, and also in other theories of gravitation that include torsion.     

Optimal Concentration for SU(1, 1) Coherent State Transforms and An Analogue of the Lieb-Wehrl Conjecture for SU(1, 1)

We derive a lower bound for the Wehrl entropy in the setting of SU(1, 1). For asymptotically high values of the quantum number k, this bound coincides with the analogue of the Lieb-Wehrl conjecture for SU(1, 1) coherent states. The bound on the entropy is proved via a sharp norm bound. The norm bound is deduced by using an interesting identity for Fisher information of SU(1, 1) coherent state transforms on the hyperbolic plane and a new family of sharp Sobolev inequalities on . To prove the sharpness of our Sobolev inequality, we need to first prove a uniqueness theorem for solutions of a semi-linear Poisson equation (which is actually the Euler-Lagrange equation for the variational problem associated with our sharp Sobolev inequality) on . Uniqueness theorems proved for similar semi-linear equations in the past do not apply here and the new features of our proof are of independent interest, as are some of the consequences we derive from the new family of Sobolev inequalities. Work partially supported by U.S. National Science Foundation grant DMS 06-00037.     

A spin-coefficient approach to Weyssenhoff fluids in Einstein-Cartan theory

The generalized Newman-Penrose formalism is used to analyze semiclassical aligned spin fluids satisfying the Weyssenhoff restriction in the framework of Einstein-Cartan theory. Some general properties are derived and the formalism is then used to obtain two classes of exact solution. One has a flat metric, but the fluid has in general nonzero acceleration, expansion, and shear. It is characterized by two arbitrary constants and two functions of two variables satisfying one partial differential equation. In the other class the fluid has nonzero acceleration and vorticity, and the free gravitational field is of typeD. It is characterized by three arbitrary constants and an arbitrary function of two spacelike coordinates.