Identification of the high-temperature superconducting phase in the Y-Ba-Cu-O system as the perovskite YBa<SUB>2</SUB>Cu<SUB>3</SUB>O<SUB>7&#177;&#948;</SUB>

The oxide responsible for high-temperature superconductivity (onset ~100 K, zero resistance above liquid N2 temperature) is found to be YBa2Cu3O7&#177;&#948;

Quantum response of weakly chaotic systems

Chaotic systems, that have a small Lyapunov exponent, do not obey the common random matrix theory predictions within a wide "weak quantum chaos" regime. This leads to a novel prediction for the rate of heating for cold atoms in optical billiards with vibrating walls. The Hamiltonian matrix of the driven system does not look like one from a Gaussian ensemble, but rather it is very sparse. This sparsity can be characterized by parameters $s$ and $g$ that reflect the percentage of large elements, and their connectivity respectively. For $g$ we use a resistor network calculation that has direct relation to the semi-linear response characteristics of the system.Comment: 7 pages, 5 figures, expanded improved versio

Guidelines for green certification of freshwater ornamental fish

Keeping colourful and fancy fishes known as ornamental fishes, aquarium fishes, or live jewels is one of the oldest and most popular hobbies in the world. The growing interest in aquarium fishes has resulted in steady increase in aquarium fish trade globally. The ornamental fish trade with a turnover of US $ 6 Billion and an annual growth rate of 8 percent offers lot of scope for development. Unfortunately India’s share in ornamental fish trade is estimated to be less than 1 % of the global trade. The major part of the export trade is based on wild collection. There is very good domestic market too, which is mainly based on domestically bred exotic species

Infrared Nonlinear Optics

Contains report on one research project.U.S. Air Force - Office of Scientific Research (Contract F49620-84-C-0010

A case of endometrial carcinoma with age related hyperkyphosis treated with definitive radiotherapy

This report describes a simple brachytherapy procedure in a patient with endometrial cancer with age related hyperkyphosis.  Sixty-eight year-old postmenopausal woman with age related hyperkyphosis presented with endometrial carcinoma, and the patient was not operated on due to associated pelvic deformity. The patient received whole pelvic radiation followed by uterovaginal brachytherapy. Patient was supported with soft pillows to support her exaggerated anterior concavity during brachytherapy procedure and execution. The brachytherapy dose was 6 Gy per fraction per week for 3 weeks using image guidance. This is probably the first reported case of endometrial cancer with age related hyperkyphosis. In spite of the associated skeletal problems, a simple brachytherapy procedure is possible and provides good result.

Chiral-symmetry restoration in the linear sigma model at nonzero temperature and baryon density

We study the chiral phase transition in the linear sigma model with 2 quark flavors and $N_c$ colors. One-loop calculations predict a first-order phase transition at both $\mu=0$ and $\mu\neq 0$. We also discuss the phase diagram and make a comparison with a thermal parametrization of existing heavy-ion experimental data.Comment: 12 pages, 6 ps-figures, LaTe

Center-of-Mass Properties of the Exciton in Quantum Wells

We present high-quality numerical calculations of the exciton center-of-mass dispersion for GaAs/AlGaAs quantum wells of widths in the range 2-20 nm. The k.p-coupling of the heavy- and light-hole bands is fully taken into account. An optimized center-of-mass transformation enhances numerical convergence. We derive an easy-to-use semi-analytical expression for the exciton groundstate mass from an ansatz for the exciton wavefunction at finite momentum. It is checked against the numerical results and found to give very good results. We also show multiband calculations of the exciton groundstate dispersion using a finite-differences scheme in real space, which can be applied to rather general heterostructures.Comment: 19 pages, 12 figures included, to be published in Phys. Rev.