On the Upper Bound for Growth Rate of Hydromagnetic Swirling- flows

We consider stability of inviscid, incompressible, hydromagnetic swirling flows. We obtained supremum for the growth rates. Growth rate has been illustrated with three standard examples. Growth rate depends up on vorticity function, velocity profile and wave number. Furthermore, we obtained upper and lower bound for neutral phase speed. Also, we derived an instability regions depending on Rayleigh-Synge-Michael discriminant, velocity profile and radii

Study of renal and ophthalmic manifestations in hypertensive disorders of pregnancy and its outcome

Background:Hypertensive diseases of pregnancy are commonly manifested in renal and ocular changes. Proper evaluation of findings provided by urine analysis, renal function test, urine output and examination of the optic fundi and visual fields may help in assessing the severity and the need for intervention. The primary objective was to determine the prevalence of retinal and renal manifestations in hypertensive disorders in pregnancy and feto-maternal outcome.Methods: This prospective study was conducted in VIMS, Ballary, Karnataka, India between 1st March 2014 to 28th February 2015. Detailed history and ocular examination with direct fundoscopy and renal parameters were noted on the mothers admitted and their correlation with feto maternal outcome studied.Results: 432 patients were included in the study, 41.7% had retinopathy changes on fundoscopy, 31.3% patients had Grade I hypertensive changes. Grade II, III and IV changes were seen in 4.2%, 2.1% and 4.2% respectively. There was an increase in blood uric acid levels with increase in severity of preeclampsia. The incidence of IUFD (8.3%), still born (8.3%) and need for NICU admission were significantly more with the severity of preeclampsia.Conclusions: Cases of hypertensive disorders in pregnancy with visual disturbances and headache are commonly associated with retinal changes. It is essential to examine every pre-eclampsia patient for ocular manifestations, which is helpful in the management of patient. Maternal urine protein test helps to detect the glomerular insult in the kidney and is a strong predictor of maternal and fetal complications

Reactions of organo-rhodium complexes with multidentate N,N and N,S-heterocycles and exchange studies by NMR

Dihalobridged binuclear complexes Rh(diolefin)(μ-X)2 {diolefin = 1,5-cyclooctadiene (cod), X = Cl or Br; diolefin = norbornadiene (nbd), X = Cl}, undergo halide bridge cleavage reactions with multidentate N,N-heterocycles 1,3,5-tris(benzimidazolyl)benzene (L1H3), 1,3,5-tris(N-methylbenzimidazolyl)benzene (L2H3) and N,S-heterocycle 1,3,5-tris(benzothiazolyl)benzene (L3H3) to yield trinuclear heterocycle bridged complexes {RhX(cod)}3(μ-LH3) and {RhCl(nbd)}3(μ-LH3) (LH3 = L1H3, L2H3, L3H3). 1H NMR exchange measurements have shown resonances for olefinic protons 1â³, 2â³, 5â³ and 6â³ of cod at different chemical shifts, perhaps due to restricted Rh-N bond rotation. The olefinic and aliphatic protons would undergo exchange with each other and also with intermediate species. The exchange mechanism may be visualized to involve Rh-N bond breaking, rotation of the cod ligand of the T-shaped (three-coordinate) intermediate species followed by recomplexation. An alternate mechanism may be Rh-cod bond breaking at olefin positions 5â³ and 6â³, isomerisation of the T-complex such that 5â³/6â³ moves trans to X coupled with rotation of the heterocycle about the Rh-N bond (made easier by the reduced coordination number of the intermediate), followed by recoordination of 1â³/2â³ trans to N, followed by recomplexation. NMR signals from the intermediate species in one dimensional 1H, 13C and 2D NMR spectra have supported the exchange of protons. © 2009 Elsevier Ltd. All rights reserved

Synthesis of rhodium(III) complexes with tris/tetrakis-benzimidazoles and benzothiazoles - quick identification of cyclometallation by nuclear magnetic resonance spectroscopy

Reactions of rhodium(III) halides with multidentate N, S-heterocycles, (LH3) 1,3,5-tris(benzimidazolyl)benzene (L1H3; 1), 1,3,5-tris(N-methylbenzimidazolyl) benzene (L2H3; 2) and 1,3,5-tris(benzothiazolyl)benzene (L3H3; 3), in the molar ratio 1 : 1 in methanol-chloroform produced mononuclear cyclometallated products of the composition RhX2 (LH2)(H2O) (X = Cl, Br, I; LH2 = L1H2, L2H 2, L3H2). When the metal to ligand (1-3 or 1,2,4,5-tetrakis(benzothiazolyl)benzene L4H2; 4) molar ratio was 2 : 1, the reactions yielded binuclear complexes of the compositions Rh2Cl5 (LH2)(H2O) 3 (LH2 = L1H2, L2H2, L 3H2) and Rh2X4 (L 4)(H2O) 2 (X= Cl, Br, I). Elemental analysis, IR and 1H nuclear magnetic resonance (NMR) chemical shifts supported the binuclear nature of the complexes. Cyclometallation was detected by conventional 13C NMR spectra that showed a doublet around �190 ppm. Cyclometallation was also detected by gradient-enhanced heteronuclear multiple bond correlation (g-HMBC) experiment that showed cross-peaks between the cyclometallated carbon and the central benzene ring protons of 1-3. Cyclometallation was substantiated by two-dimensional 1H- 1H correlated experiments (gradiant-correlation spectroscopy and rotating frame Overhauser effect spectroscopy) and 1H-13C single bond correlated two-dimensional NMR experiments (gradient-enhanced heteronuclear single quantum coherence). The 1H-15N g-HMBC experiment suggested the coordination of the heterocycles to the metal ion via tertiary nitrogen. © 2009 John Wiley & Sons, Ltd

Internal heat generation effect on mixed convection heat and mass transfer over a vertical heated plate with Soret and Dufour effects

Study and analysis of internal heat generation effect of two-dimensional, steady, laminar, heat and mass transfer mixed convection flow of a viscous incompressible fluid from a vertical heated plate embedded in a sparsely packed porous medium with variable fluid properties such as permeability, porosity, thermal conductivity and solutal diffusivity with the Soret and Dufour effects are considered and studied numerically. The boundary layer flow in the porous medium is governed by Lapwood-Forcheimer-Brinkman extended Darcy model. Please download the full abstract below

Surgical management of vaginal agenesis using a modified Mc Indoe’s technique: VIMS experience

Background: Mullerian agenesis is a challenge to reconstructive surgeons. In order to create a new vagina that mimic the normal one in size, lining and appearance, multiple techniques have been designed; among these techniques Mc Indoe’s vaginoplasty represents the simplest one with good results. Mc Indoe’s operation which involves the creation of a space between bladder and rectum, insertion of a mould covered with split-thickness skin graft into that neo-vaginal space, and use of postoperative vaginal mould for dilation and to avoid stenosis. However, many modifications have been introduced in time in an attempt to increase the success rates. The purpose of vaginal agencies treatment is to create an adequate passage for penetration during sexual intercourse.Methods: Between Jan 2010 to June 2017, ten patients with vaginal agenesis were admitted to Dept of Obstetrics and Gynaecology, VIMS Ballari for vaginal reconstruction. All cases underwent a modified Mc Indoe’s technique, and follow up was done for one year.Results: All ten cases of vaginal agenesis underwent vaginal reconstruction by modified Mc Indoe's technique. Post-operative vaginal length varied from 5 to 7 cm in patients who used mould regularly. Successful skin graft take was achieved in 6 cases. one case of perforation of rectum and one case of vaginal stricture was noted.Conclusions: To optimize sexual comfort, the clinical management of women with vaginal agenesis must be multidisciplinary and individually tailored. Our findings suggest that the modified Mc Indoe’s technique is a simple, effective procedure for the treatment of vaginal agenesis, but proper mould usage after surgery remains the cornerstone of the treatment

Doping Dependence of Thermal Oxidation on n-type 4H-SiC

The doping dependence of dry thermal oxidation rates in n-type 4H-SiC was investigated. The oxidation was performed in the temperature range 1000C to 1200C for samples with nitrogen doping in the range of 6.5e15/cm3 to 9.3e18/cm3, showing a clear doping dependence. Samples with higher doping concentrations displayed higher oxidation rates. The results were interpreted using a modified Deal-Grove model. Linear and parabolic rate constants and activation energies were extracted. Increasing nitrogen led to an increase in linear rate constant pre-exponential factor from 10-6m/s to 10-2m/s and the parabolic rate constant pre-exponential factor from 10e9m2/s to 10e6m2/s. The increase in linear rate constant was attributed to defects from doping-induced lattice mismatch, which tend to be more reactive than bulk crystal regions. The increase in the diffusion-limited parabolic rate constant was attributed to degradation in oxide quality originating from the doping-induced lattice mismatch. This degradation was confirmed by the observation of a decrease in optical density of the grown oxide films from 1.4 to 1.24. The linear activation energy varied from 1.6eV to 2.8eV, while the parabolic activation energy varied from 2.7eV to 3.3eV, increasing with doping concentration. These increased activation energies were attributed to higher nitrogen content, leading to an increase in effective bond energy stemming from the difference in C-Si (2.82eV) and Si-N (4.26eV) binding energies. This work provides crucial information in the engineering of SiO2 dielectrics for SiC MOS structures, which typically involve regions of very different doping concentrations, and suggests that thermal oxidation at high doping concentrations in SiC may be defect mediated.Comment: 13 pages. 9 figures, accepted as a transiction in IEEE electron device. TED MS#8035