Spherical collapse with heat flow and without horizon

We present a class of solutions for a heat conducting fluid sphere, which radiates energy during collapse without the appearance of horizon at the boundary at any stage of the collapse. A simple model shows that there is no accumulation of energy due to collapse since it radiates out at the same rate as it is being generated.Comment: RevTeX, 3 page

Magnetic Response in a Zigzag Carbon Nanotube

Magnetic response of interacting electrons in a zigzag carbon nanotube threaded by a magnetic flux is investigated within a Hartree-Fock mean field approach. Following the description of energy spectra for both non-interacting and interacting cases we analyze the behavior of persistent current in individual branches of a nanotube. Our present investigation leads to a possibility of getting a filling-dependent metal-insulator transition in a zigzag carbon nanotube.Comment: 9 pages, 14 figure

Role of covalency in the ground state properties of perovskite ruthenates: A first principle study using local spin density approximations

We investigate the electronic structure of SrRuO3 and CaRuO3 using full potential linearized augmented plane wave method within the local spin density approximations. The ferromagnetic ground state in SrRuO3 could exactly be described in these calculations and the calculated spin magnetic moment is found to be close to the experimentally observed values. Interestingly, the spin polarized calculations for CaRuO3 exhibit large spin moment as observed in the experiments but the magnetic ground state has higher energy than that in the non-magnetic solution. Various calculations for different structural configurations indicate that Ca-O covalency plays the key role in determining the electronic structure and thereby the magnetic ground state in this system.Comment: 8 figure

Use of an Innovative Simple Method for Anaerobiosis in the Diagnosis and Management of Infections in Two Unusual Cases

Technical limitations restrict routine anaerobe isolation from clinical materials in resource‑limited laboratories. An innovative two steps combustion candle jar technique may be suitable for such setup. This system was tried with one case of chronic osteomyelitis developed on supracondyler compound fracture. Porphyromonas spp. was isolated and identified. Vancomycin was recommended based on in vitro sensitivity test, but the leg was amputed after receiving a resistant drug gentamycin. While in another child with hydrocephalous, V‑P shunt associated infection by Peptostreptococcus anaerobius was successfully controlled by sensitive drug vancomycin. These two eye‑opener cases insisted us for large scale application of the technique.Keywords: Anaerobiosis, Candle‑jar technique, Osteomyelitis, Porphyromonas spp, V‑P shunt infectio

Nb(III) Trisoxinate & Niobyl Phosphoniobate

43-4

Correlation and surface effects in Vanadium Oxides

Recent photoemission experiments have shown strong surface modifications in the spectra from vanadium oxides as (V,Cr)_2O_3 or (Sr,Ca)VO_3. The effective mass is enhanced at the surface and the coherent part of the surface spectrum is narrowed as compared to the bulk. The quasiparticle weight is more sensitive at the surface than in the bulk against bandwidth variations. We investigate these effects theoretically considering the single-band Hubbard model for a film geometry. A simplified dynamical mean-field scheme is used to calculate the main features of the interacting layer-dependent spectral function. It turns out that the experimentally confirmed effects are inherent properties of a system of strongly correlated electrons. The reduction of the weight and the variance of the coherent part of the surface spectrum can be traced back to the reduced surface coordination number. Surface correlation effects can be strongly amplified by changes of the hopping integrals at the surface.Comment: to appear in PRB; 8 pages, 6 figure

Antifertility effect of curcumin, an indigenous medicine in rats

Background: Curcumin is an active constituent, obtained from rhizome of Curcuma longa linn, known to have broad medicinal properties, was studied for its effect on fertility in female rats. Curcumin has anti-ovulatory effect probably by its antiestrogenic activity through suppression of negative feedback of estrogen on pituitary.Methods: Inbred Charles Foster female albino rats (150-180 gm) were used for study. They were divided into different groups and treated with curcumin (25 mg/kg. and 50 mg/kg body weight) as per schedule. The antigonadotropic, antiestrogenic, anti-implantation and abortifacient effect on curcumin treated albino rats were demonstrated.Results: The results showed significant reduction in the number of implants and size of litters in curcumin treated rats compared to normal control group. The results were compared with Tamoxifen (10mg/ kg bodyweight) a known antifertility drug, which further substantiated the antifertility effects of curcumin.Conclusions: The results indicated the ways in which curcumin exerts antifertility effects and thus can play a vital role in fertility control

Shear-free radiating collapse and conformal flatness

Here we study some general properties of spherical shear-free collapse. Its general solution when imposing conformal flatness is reobtained [1,2] and matched to the outgoing Vaidya spacetime. We propose a simple model satisfying these conditions and study its physical consequences. Special attention deserve, the role played by relaxational processes and the conspicuous link betweeen dissipation and density inhomogeneity.Comment: 13 pages Latex. Some misprints in eqs.(17), (30) and (35) have been correcte

An iterative regression approach for prediction of sorghum (sorghum bicolor) phenology in the semi-arid tropics

Equations are derived to predict the duration of three growth stages of sorghum under adequate moisture and nutrient availability, on the basis of temperature and relative humidity, following an iterative regression approach. The predictions are very good. The response of temperature on phenophase duration was curvilinear. The common base temperature of 10°C and the point of inflection temperature of 19.6°C are shared by all the 4 genotypes studied, but the degree of response in development by each of them varied considerably. The response for each growth stage was different. This study also presents a simple iterative regression approach to solve non-linear functions. This procedure is very valuable where facilities such as sophisticated computers or programmable calculators are lacking