17 research outputs found
Mutations of rpob Gene Associated with Rifampin Resistance among Mycobacterium Tuberculosis Isolated in Tuberculosis Regional Reference Laboratory in Northeast of Iran during 2015-2016
Background: Drug resistance is a leading concern in control of TB. Resistance against rifampin as one of the most important drugs in the treatment of Mycobacterium tuberculosis is caused by mutations in the 81-base pair region of the rpoB gene encoding the β-subunit of RNA polymerase. This study aimed to characterize the mutations in the rpoB gene associated with rifampin resistance among M. tuberculosis. Methods: This study was conducted on referred samples of patients who did not respond to anti-TB treatment, in Tuberculosis Regional Reference Laboratory at Shariati Hospital. Drug susceptibility of M. tuberculosis isolates was surveyed using a proportional method on LJ medium. The isolates with resistant to rifampin were reconfirmed and then the rpoB gene was amplified and sequenced. Results: Among 27 resistant cases, 8, 11 and 8 people were from Iran, Afghanistan, and Turkmenistan, respectively. In 26 out of 27 isolates, rpoB gene mutations were observed. The most prevalent mutations belonged to the codon 53. The most prevalent mutations belonged to the TCG (Ser) 531TTG (leu) with prevalence 51.8 (n=14), and GAC (Asp)516TAC (Tyr), CAC (His) 526GAC (Asp) and CAC (His) 526TAC(Tyr) mutations with prevalence 14.8(n=4). Twenty-three isolates had just one mutation. Conclusion: The use of rpoB gene sequencing led to the lack of the need for growth of the organism in the culture medium, the direct use of clinical samples, reduction of biological risks and a detection about 96.3 of MDR TB cases lowering the cost of the treatment
Influence of the Vertex Region on Spin Dynamics in Artificial Kagome Spin Ice
We present experimental and theoretical studies of spin-wave mode dynamics in artificial kagome spin ice vertices made of three identical 15-nm thick elongated Ni80Fe20 nanoislands (macrospins). We consider several possible configurations, from completely disjointed macrospins (full dipolar interelement interactions) to fully jointed macrospins (full dipolar-exchange interactions). Using angular-resolved magnetic field dependent broadband ferromagnetic resonance (FMR), we demonstrate the occurrence of a mode localized in the vertex region as indicated by the distinct behavior of the FMR spectra at different angles and configurations. Theoretical calculations using micromagnetic simulations support the existence, origin, and behavior of this mode by interpreting it as a localized, quasi-uniform Kittel mode. Our findings pave the way for designing the most appropriate network consisting of ferromagnetic nanomagnets for specific application purposes in magnonics
Data envelopment analysis in financial services: a citations network analysis of banks, insurance companies and money market funds
Development and application of the data envelopment analysis (DEA) method, have been the subject of numerous reviews. In this paper, we consider the papers that apply DEA methods specifically to financial services, or which use financial services data to experiment with a newly introduced DEA model. We examine 620 papers published in journals indexed in the Web of Science database, from 1985 to April 2016. We analyse the sample applying citations network analysis. This paper investigates the DEA method and its applications in financial services. We analyse the diffusion of DEA in three sub-samples: (1) banking groups, (2) money market funds, and (3) insurance groups by identifying the main paths, that is, the main flows of the ideas underlying each area of research. This allows us to highlight the main approaches, models and efficiency types used in each research areas. No unique methodological preference emerges within these areas. Innovations in the DEA methodologies (network models, slacks based models, directional distance models and Nash bargaining game) clearly dominate recent research. For each subsample, we describe the geographical distribution of these studies, and provide some basic statistics related to the most active journals and scholars
The effect of topical application of autologous blood serum and platelet rich plasma mixture on clinical vision improvement after induction of experimental corneal stromal ulcers in rabbit
Corneal ulcers which are mostly due to trauma are among the most common ocular disorders of animals that if not cured properly, might progress to blindness. In this research, the effects of platelet derived rich plasma (PRP) combined with autologous blood serum on vision improvement time (attainment of maximum corneal clarity) following creation of deep corneal stromal ulcer was evaluated. For this purpose, 25 adult male New Zealand which rabbits which were allocated to three groups of positive control (10 rabbits), negative control (5 rabbits) and treatment (10 rabbits) were used. In the control corneal regions of each animal, a deep stromal ulcer (extending from the corneal epithelium to the last stromal layer) with a diameter of 4mm was created by means of a probe. Then in the treatment group, pre-prepared PRP was placed immediately on the ulcer and autologous serum drop was administered as 2 drop, 3 times per day for 35 days. In the positive control group Chloramphenicol, Ciprofloxacin and Naphazoline ophthalmic drops and in the negative control group only distilled water were used in the same manner. During the 35 days of the study period, the visual status of the rabbits was evaluated daily. Based on clinical examinations, the treatment group achieved ideal vision significantly faster than the negative and positive control groups and the created ulcer had healed with the least amount of scar production (maximum light penetration from the cornea). Based on the results of this study, the used of PRP is recommended in the treatment of superficial to deep corneal ulcers to obtain faster heading, better vision improvement and least scar production
Ferromagnetic resonance spectra of permalloy nano-ellipses as building blocks for complex magnonic lattices
We report the experimental and theoretical characterization of the angular dependent magnetic field and microwave frequency response of isolated mesoscopic permalloy nanoellipses for geometries in which the static magnetic field is either parallel or perpendicular to the microwave magnetic field. We show how these spectra form a basis for interpreting the ferromagnetic resonance spectra of lattices based on such structures, including those containing frustrated regions, such as artificial spin ice structures
Investigation of Two Immiscible Liquids Wetting at Elevated Temperature: Interaction Between Liquid FeMn Alloy and Liquid Slag
The goal of the current work is to develop a methodology to study the wetting behaviour of two immiscible liquids at high temperatures, and to investigate the parameters which influence the wetting properties. The wetting behaviour between synthetic FeMn alloy and synthetic slag has been investigated using the sessile drop technique. Two experimental procedures were implemented under both Ar and CO atmospheres: (a) FeMn alloy and slag placed next to each other on a graphite substrate; and (b) one droplet dropped on top of the other. FactSage is applied to calculate reactions and their equilibrium. The current work presents and demonstrates the suggested methodologies. The results indicate that the wetting between slag and FeMn alloy is relatively stable at temperatures up to 100 K above their melting points, regardless of the droplet size and atmosphere. MnO reduction is accelerated at higher temperature, especially in CO, thus increasing the wetting between FeMn alloy and slag, eventually fusing together. At even higher temperature, slag separates from FeMn alloy due to changing chemical composition during non-equilibrium MnO reduction