Field theoretic calculation of scalar turbulence

The cascade rate of passive scalar and Bachelor's constant in scalar turbulence are calculated using the flux formula. This calculation is done to first order in perturbation series. Batchelor's constant in three dimension is found to be approximately 1.25. In higher dimension, the constant increases as $d^{1/3}$.Comment: RevTex4, publ. in Int. J. Mod. Phy. B, v.15, p.3419, 200

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

Leptogenesis in a Hybrid Texture Neutrino Mass Model

We investigate the CP asymmetry for a hybrid texture of the neutrino mass matrix predicted by $Q_8$ family symmetry in the context of the type-I seesaw mechanism and examine its consequences for leptogenesis. We, also, calculate the resulting Baryon Asymmetry of the Universe (BAU) for this texture.Comment: Accepted for publication in Mod. Phys. Lett.

Fabrication and testing of a multifunctional SiO2@ZnO core-shell nanospheres incorporated polymer coating for sustainable marine transport

We report the development of a coating system relying on the incorporation of SiO2@ZnO coreshel nanospheres in polyurethane media as a novel approach to achieve longevity and sustainability in marine transport. This polymeric coating showed significant improvement in surface abrasion resistance, the transition from a hydrophilic state to a hydrophobic state (~125.2± 2°), improved antifungal, antibacterial and antialgae effects which make the proposed coating ideal to protect steel surfaces against biofouling. To substantiate our claims, we performed X-Ray diffraction, Transmission electron microscopy, Fourier transform infrared spectroscopy, scanning acoustic microscopy, Thermogravimetric analysis (TGA), contact angle measurements, antimicrobial (antialgal, antibacterial, antifungal) tests and Taber abrasion tests (ASTM D1044 and D4060) to highlight the mechanical and biological functionality as well as the bonding configuration of this coating. The wear analysis of the Taber abraded coating using SEM and optical microscopy showed significant improvement in the adhesion and shear resistance achieved by the SiO2@ZnO core-shell nanospheres incorporated PU coating which was a contrasting feature compared to using PU alone. The overall investigations we performed led us to find out that the addition of 4% (wt.) SiO2@ZnO core-shell nanoparticles to the PU media deposited on the low carbon steel surface demonstrated remarkable antimicrobial performance with almost no bacterial growth, significant reductions in growth for algae to about 9.2% and fungus to about 10.2%

Large-Eddy Simulations of Fluid and Magnetohydrodynamic Turbulence Using Renormalized Parameters

In this paper a procedure for large-eddy simulation (LES) has been devised for fluid and magnetohydrodynamic turbulence in Fourier space using the renormalized parameters. The parameters calculated using field theory have been taken from recent papers by Verma [Phys. Rev. E, 2001; Phys. Plasmas, 2001]. We have carried out LES on $64^3$ grid. These results match quite well with direct numerical simulations of $128^3$. We show that proper choice of parameter is necessary in LES.Comment: 12 pages, 4 figures: Proper figures inserte

Association between Takayasu’s arteritis and active tuberculosis in a child: A case report

Takayasu’s arteritis (TA) is an autoimmune disease that affects large arteries. A possible relationship between TA and tuberculosis (TB)has been suggested as both diseases have similar chronic inflammatory lesions and occasionally granulomas in the arterial walls. TAcommonly presents with cardiac involvement and rarely with sole presentation of ischemic stroke. Response with anti-tubercular drugsand steroid has been well-documented. Only a few studies have been published on TA with TB in children. We present a case of a 9-yearoldboy who was presented with low-grade fever, persistent headache, vomiting, and abnormal body movements and on further workupwas diagnosed as a case of active TB with TA

Local shell-to-shell energy transfer via nonlocal Interactions in fluid turbulence

In this paper we analytically compute the strength of nonlinear interactions in a triad, and the energy exchanges between wavenumber shells in incompressible fluid turbulence. The computation has been done using first-order perturbative field theory. In three dimension, magnitude of triad interactions is large for nonlocal triads, and small for local triads. However, the shell-to-shell energy transfer rate is found to be local and forward. This result is due to the fact that the nonlocal triads occupy much less Fourier space volume than the local ones. The analytical results on three-dimensional shell-to-shell energy transfer match with their numerical counterparts. In two-dimensional turbulence, the energy transfer rates to the near-by shells are forward, but to the distant shells are backward; the cumulative effect is an inverse cascade of energy.Comment: 10 pages, Revtex

Pyrazole-based analogs as potential antibacterial agents against methicillin-resistance staphylococcus aureus (MRSA) and its SAR elucidation

Methicillin-resistant Staphylococcus aureus (MRSA) is becoming lethal to humanity due to easy transmission and difficult-to-treat skin and flimsy diseases. The most threatening aspect is the rapid resistance development of MRSA to any approved antibiotics, including vancomycin. The development of new, efficient, and nontoxic drug candidate to fight against MRSA isolates is the need of the hour. The intriguing molecular structure and versatile bioactive pyrazole core attracting to development required novel antibiotics. This review presents the decade developments of pyrazole-containing derivatives with a broad antibacterial movement against diverged bacterial strains. In specific, we correlated the efficacy of structurally diversified pyrazole analogs against MRSA and discussed different angles of structure-activity relationship (SAR). The current survey highlights pyrazole hybrids' present scenario on MRSA studies, covering articles published from 2011 to 2020. This collective information may become an excellent platform to plan and develop new pyrazole-based small MRSA growth inhibitors with minimal side effects. (C) 2020 Elsevier Masson SAS. All rights reserved