Revised Analytical Methods for the Determination of Carbonic Species in Rain, Ground and Geothermal Waters

ABSTRACT The concentration of carbonic species (H 2 CO 3 , HCO 3 -and CO 3 2-) in natural waters is determined by the volumetric acid-base titration. In the case of low concentration carbonic water (e.g. rainwater), the Gran titration method is used. The application and limitations of the Gran titration method are discussed. The Gran titration method is based on locating the linear tendency of Gran functions F 1 to F 6 . However, it is impossible to find the linear tendency of functions F 2 , F 3 , F 5 and F 6 . Thus, in the case of rainwater, the Gran titration method is modified using only F 1 and F 4 . The titration methods for ground and geothermal waters are revised. The pH of the equivalence points, H 2 CO 3 EP, NaHCO 3 EP, and Na 2 CO 3 EP depends on the total dissolved carbonic concentration C T in a solution. Therefore, the location of the equivalence points through the corresponding points of inflexion is suggested. The procedure for groundwater containing only carbonic alkalinity is called here as Method 1. The titration procedure for geothermal waters, Method 2, used by geochemists is conceptually incorrect. It is shown theoretically that there is an error of 14.59, 14.00, 17.84 and 19.92 % in the determination of carbonic species of pure Na 2 CO 3 solutions C T =0.05, 0.03, 0.01 and 0.005 m, respectively. The backward titration from H 2 CO 3 EP to the original pH after CO 2 removal, as had been practiced earlier in geothermal industry in order to estimate the contribution of silicic and boric alkalinities to the total alkalinity, is incorrect because the amount of standard base (NaOH) added is equivalent to silicic and boric alkalinities plus some OH -alkalinity. In a Na 2 CO 3 solution the added NaOH is equivalent to OH -alkalinity only. The backward titration is only needed from the forward titration end point to the H 2 CO 3 EP in order to correct the total alkalinity for the excess of standard acid (HCl) added during the forward titration. In the case of a Na 2 CO 3 solution, the H 2 CO 3 EP, after removal of CO 2 during the forward titration, is at pH=7, but not at pH=4.5 (3.8) as has been considered in literature. The revised procedure for the determination of carbonic species concentration is presented and illustrated for natural waters

Calculation of renormalized viscosity and resistivity in magnetohydrodynamic turbulence

A self-consistent renormalization (RG) scheme has been applied to nonhelical magnetohydrodynamic turbulence with normalized cross helicity $\sigma_c =0$ and $\sigma_c \to 1$. Kolmogorov's 5/3 powerlaw is assumed in order to compute the renormalized parameters. It has been shown that the RG fixed point is stable for $d \ge d_c \approx 2.2$. The renormalized viscosity $\nu^*$ and resistivity $\eta^*$ have been calculated, and they are found to be positive for all parameter regimes. For $\sigma_c=0$ and large Alfv\'{e}n ratio (ratio of kinetic and magnetic energies) $r_A$, $\nu^*=0.36$ and $\eta^*=0.85$. As $r_A$ is decreased, $\nu^*$ increases and $\eta^*$ decreases, untill $r_A \approx 0.25$ where both $\nu^*$ and $\eta^*$ are approximately zero. For large $d$, both $\nu^*$ and $\eta^*$ vary as $d^{-1/2}$. The renormalized parameters for the case $\sigma_c \to 1$ are also reported.Comment: 19 pages REVTEX, 3 ps files (Phys. Plasmas, v8, 3945, 2001

Prevalence and fungal profile of pulmonary aspergillosis in immunocompromised and immunocompetent patients of a tertiary care hospital

Background: Aspergillus is a fungus which may present an array of pulmonary manifestations, depending on the patient’s immunological and physiological state. Although the incidence of pulmonary aspergillosis occurs primarily in immunocompromised patients but the incidence is also rising in immunocompetent individuals, especially in developing countries. Aim: The objective of the study was to determine the prevalence and predisposing factors of pulmonary aspergillosis along with species identification. Materials and Methods: One hundred and three patients admitted to the Department of Chest and Tuberculosis and in the Department of Medicine from Jan 2012 to Jan 2013 were included in this study. The patients were epitomized on the basis of clinical signs and symptoms, physical examination, chest radiography, CT scans, histopathological examination, bronchoscopy and fungal examination including potassium hydroxide mount, fungal culture of sputum and bronchoalveolar lavage. Species identification was done by colony characteristics, slide culture and Lactophenol Cotton blue mount. Results: Out of the 103 patients, (63 males and 40 females) Aspergillus species has been isolated from 17 (16.5%) males and 07 (6.79%) females. Various predisposing factors of pulmonary aspergillosis have been identified in which pulmonary tuberculosis, chronic smoking and environmental exposure to asbestos, cement its tops the list. Many of the patients had multiple predisposing factors. Aspergillus species were isolated in 24 (23.3%) cases. Aspergillus fumigatus was the predominant species isolated in 13 (54.16%) cases followed by Aspergillus flavus in 07 (29.16%) cases, Aspergillus niger in 03 (12.5 %) and Aspergillus terrus in 1 (4.16%) cases. Conclusion: It is concluded that the prevalence of pulmonary Aspergillosis is quite high in immunocompromised individuals and low in immunocompetent individuals. An adequate and efficient evaluation of the etiological agents has a crucial role in the management of such patients

Shell model for buoyancy-driven turbulence

In this paper we present a unified shell model for stably stratified and convective turbulence. Numerical simulation of this model for stably stratified flow shows Bolgiano-Obukhbov scaling in which the kinetic energy spectrum varies as $k^{-11/5}$. We also observe a dual scaling ($k^{-11/5}$ and $k^{-5/3}$) for a limited range of parameters. The shell model of convective turbulence yields Kolmogorov's spectrum. These results are consistent with the energy flux and energy feed due to buoyancy, and are in good agreement with direct numerical simulations of Kumar {\em et al.} [Phys. Rev. E {\bf 90}, 023016 (2014)]

Energy fluxes in helical magnetohydrodynamics and dynamo action

Renormalized viscosity, renormalized resistivity, and various energy fluxes are calculated for helical magnetohydrodynamics using perturbative field theory. The calculation is to first-order in perturbation. Kinetic and magnetic helicities do not affect the renormalized parameters, but they induce an inverse cascade of magnetic energy. The sources for the the large-scale magnetic field have been shown to be (1) energy flux from large-scale velocity field to large-scale magnetic field arising due to nonhelical interactions, and (2) inverse energy flux of magnetic energy caused by helical interactions. Based on our flux results, a premitive model for galactic dynamo has been constructed. Our calculations yields dynamo time-scale for a typical galaxy to be of the order of $10^8$ years. Our field-theoretic calculations also reveal that the flux of magnetic helicity is backward, consistent with the earlier observations based on absolute equilibrium theory.Comment: REVTEX4; A factor of 2 corrected in helicit

Percutaneous cystolithotripsy in children and its outcome: A single center experience

Background: Pediatric bladder stone disease is very common in certain regions of India. Traditionally, pediatric surgeons have been managing this by open surgeries. Aim: The aim of the study was to manage vesical calculus in children by percutaneous cystolithotripsy (PCCL). Materials and Methods: All the children up to 18 years of age suffering from vesical calculus were operated by PCCL. Cystoscopy performed first to assess the stone burden. 18 Fr angiocath needle was used to puncture the bladder under vision and 0.035 guide wire was passed. Tract was dilated using single-step screw dilator; a 20 French Amplatz sheath was passed over the screw dilator and nephroscope was introduced. Lithotripsy was done using pneumatic lithotripter. Per urethral Foley catheter was placed and suprapubic puncture site was suture closed. Results: A total of 74 patients were operated in the past 3 years with an age range was 1–18 years with female preponderance. Complete clearance was achieved in all patients while the average duration of surgery was 30 min with range of 15–50 min. All the patients were operated under regional anesthesia and were discharged the next day. Among the study population, three patients had superficial wound infections at the puncture site which was managed conservatively. Conclusion: PCCL is a good option for managing vesical calculus in children. It has minimal morbidity and very small scar as compared to open cystolithotomy. Even in recurrent stones, it can be effectively performed, and in fact, it is easy to learn and reproducible

Energy spectrum of buoyancy-driven turbulence

Using high-resolution direct numerical simulation and arguments based on the kinetic energy flux $\Pi_u$, we demonstrate that for stably stratified flows, the kinetic energy spectrum $E_u(k) \sim k^{-11/5}$, the entropy spectrum $E_\theta(k) \sim k^{-7/5}$, and $\Pi_u(k) \sim k^{-4/5}$, consistent with the Bolgiano-Obukhov scaling. This scaling arises due to the conversion of kinetic energy to the potential energy by buoyancy. For weaker buoyancy, this conversion is weak, hence $E_u(k)$ follows Kolmogorov's spectrum with a constant energy flux. For Rayleigh B\'{e}nard convection, we show that the energy supply rate by buoyancy is positive, which leads to an increasing $\Pi_u(k)$ with $k$, thus ruling out Bolgiano-Obukhov scaling for the convective turbulence. Our numerical results show that convective turbulence for unit Prandt number exhibits a constant $\Pi_u(k)$ and $E_u(k) \sim k^{-5/3}$ for a narrow band of wavenumbers.Comment: arXiv admin note: text overlap with arXiv:1404.214

Shifting support for inequitable gender norms among young Indian men to reduce HIV risk and partner violence

India accounts for the second largest population of people living with HIV/AIDS (5.1 million), and almost half of new infections occur in young men below age 30. While there are multiple factors influencing young men’s HIV risk in India, one that is receiving increasing attention is early socialization about masculinity. Young men in India mature and develop in a male-dominated context, having little contact with female peers and virtually no sex education. In this context, most boys develop a sense of masculinity characterized by male dominance in the sexual arena and other areas. Although there is increasing awareness of the role that norms that encourage gender inequality play in fostering HIV risk behaviors and partner violence, few studies have attempted to influence these norms and measure changes in support for them among young men exposed to an intervention. As detailed in this research summary, the Horizons Program, CORO for Literacy, and Instituto PROMUNDO conducted operations research to examine the impact on young men of promoting gender equity as part of an HIV-prevention program

Energy Flux and Bottleneck Effect in Turbulence

Past numerical simulations and experiments of turbulence exhibit a hump in the inertial range, called the bottleneck effect. In this paper we show that sufficiently large inertial range (four decades) is required for an effective energy cascade. We propose that the bottleneck effect is due to the insufficient inertial range available in the reported simulations and experiments. To facilitate the turbulent energy transfer, the spectrum near Kolmogorov's dissipation wavenumber has a hump.Comment: 11 pages, 4 Figures, Revte