Finsler Metrics with Bounded Cartan Torsions

The norm of Cartan torsion plays an important role for studying of immersion theory in Finsler geometry. Indeed, Finsler manifold with unbounded Cartan torsion can not be isometrically imbedded into any Minkowski space. In this paper, we find two subclasses of (?, ?)-metrics which have bounded Cartan torsion. Then, we give two subclasses of (?, ?)-metrics whose bound on the Cartan torsions are independent of the norm of ?

Finite-Difference Time-Domain Simulations of Radon Transport in Porous Media

In this work, an efficient algorithm, using a finite-difference time-domain (FDTD) technique, is proposed for modeling the variation of radon concentration as a function of soil structure parameters and vice versa. The development of the FDTD model is based on the simultaneous resolution of the radon transport equation in a porous, homogeneous medium, namely the soil. This equation describes the concentration of radon per pore volume unit. The numerical results are compared with those of the literature or with the theoretical ones

The generalized second law in chameleon cosmology

In this paper, we investigate the validity of the generalized second law (GSL) of thermodynamics in flat FRW chameleon cosmology where the boundary of the universe is assumed to be enclosed by the dynamical apparent horizon. It has been shown that, in a bouncing scenario for the universe with phantom crossing, the total entropy decreases with time in the contracting epoch, whereas, the dynamics of the internal and horizon entropies depends on the behavior of both equation of state and hubble parameters.Comment: 10 pages, 6 figures; To be published in Can. J. Phy

Comparison of quinolone and β-lactam resistance among Escherichia coli strains isolated from urinary tract infections

The growing frequency of antibiotic resistances is now a universal problem. Increasing resistance to new generations of β-lactam and quinolone antibiotics in multidrug- resistant Enterobacteriaceae isolates is considered an emergency health issue worldwide. The aim of this study was to evaluate plasmid-mediated quinolone resistance genes in ESBL-producing Escherichia coli isolated from urinary tract infections (UTIs). In our study ESBL- producing isolates were assessed by screening methods. After determination of antimicrobial susceptibility, detection of ESBLs and quinolone resistance genes was performed. A total of 97 ESBL-producing E. coli were determined. The blaTEM, blaSHV and blaCTX-M genes were detected in 90 isolates. The blaTEM was the most frequent- ly detected gene (46.4), followed by blaSHV (31.9) and blaCTX-M (14.4). The most prevalent quinolone resistance gene among ESBL-producing isolates was oqxAB which found in 67 isolates (69.1). The frequencies of the aac(6�)-Ib-cr, qnr and qepA were 65 (67), 8 (8.2) and 6 (6.2), respectively. Our data indicate that the prevalence of plasmid-mediated quinolone resistance genes in ESBL-positive isolates is increasing. The co-dissemination of PMQR and ESBL genes among E. coli isolates can be considered a threat to public health. Therefore, prescription of antibiotics against infectious disease should be managed carefully. © 2016, International Society of Musculoskeletal and Neuronal Interactions. All rights reserved

Structure, Wettability, Corrosion and Biocompatibility of Nitinol Treated by Alkaline Hydrothermal and Hydrophobic Functionalization for Cardiovascular Applications

The main objective of this study is to hydrophobize nitinol (Ni-Ti alloy) for cardiovascular applications. For this purpose, medical nitinol samples were subjected to sodium hydroxide hydrothermal treatments at various temperatures, followed by hexadecyltrimethoxysilane (HDTMS) functionalization. Then, the structure, wettability, corrosion, cytocompatibility and cell adhesion of the prepared samples were evaluated. According to the results, porous blade-shaped layers of sodium titanate were formed on the substrate surface as a result of the alkaline treatment. These nano-rough features offered considerable hydrophobicity after HDTMS processing, where a maximum water contact angle of about 140° was obtained for the sample treated at 120 °C, followed by the HDTMS coating. In contrast to the individual application of the alkaline treatments, the subsequent HDTMS processing improved corrosion resistance in the simulated body fluid. Although all the samples presented appropriate cytocompatibility with respect to human umbilical vein endothelial cells, the cells did not show an adhesion tendency to the hydrophobic surfaces. It is concluded that alkaline hydrothermal and HDTMS processed nitinol can be considered for cardiovascular applications demanding hydrophobic surfaces