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Sefidi F.J.,Tehran University of Medical Sciences | Keyvani H.,Tehran University of Medical Sciences | Monavari S.H.,Tehran University of Medical Sciences | Alavian S.M.,Baqiyatallah Research Center for Gastroenterology and Liver Diseases | And 2 more authors.
Hepatitis Monthly | Year: 2013

Background: Hepatitis C virus (HCV) has different genotypes throughout the world. Since the determination of which antiviral treatment to be applied is related to HCV genotypes, identification of an individual's HCV genotypes prior to antiviral therapy is critical. Objectives: The purpose of this study was to investigate the distribution of HCV genotypes in a large population of Iranian HCV infected patients. Patients and Methods: Eleven thousand, five hundred and sixty one patients with chronic HCV infection which referred to hospitals related to the Tehran University of Medical Sciences and Tehran Hepatitis Center-Clinical Department of Baqiyatallah Research Center for Gastroeneterology and Liver Disease from March 2003 to December 2011 were enrolled. Following extraction of viral RNA of the serum, HCV-RNA was detected using reverse transcriptase-nested polymerase chain reaction (RT-nested PCR) and then HCV genotypes analyzed by restriction fragment length polymorphism (RFLP) assay. Results: The mean age of patients was 37.6 ± 14.2 years (range: 1-87). The highest frequency was noted for subtype 1a (44.9%) followed by subtype 3a (39.6%), and 1b (11.3%). Mixed HCV genotypes were also found in 2.5% of the total cases. Subtype 1a was the most frequent genotype in patients over 40 years of age (46.1% versus 42.4%) and subtype 3a was the most frequent in patients under 40 years old (41.5% versus 38.9%). Conclusions: This study suggested that the dominant HCV subtype among Iranian patients was 1a followed by subtype 3a. © 2013, Kowsar Corp.

Savaloni H.,University of Tehran | Farid-Shayegan F.,Islamic Azad University at Shahre Qods
Vacuum | Year: 2010

Titanium films of different thicknesses were deposited on glass substrates, using planar magnetron sputtering at 313 K substrate temperature. Their optical properties were measured by spectrophotometry in the spectral range of 200-2500 nm. Kramers-Kronig method was used for the analysis of the reflectivity curves of Ti films to obtain the optical constants of the films. In order to compare the influence of thickness of Ti films prepared using two different PVD methods, namely sputtering and electron gun depositions on the optical properties of Ti films, the optical results of Savaloni and Kangarloo (2007) for Ti films produced using electron gun deposition under UHV condition at 313 K substrate temperature are incorporated in this work. The analysis of the residual stress in the sputter deposited films using sin2 ψ technique and the nano-strain in the E. Gun deposited films obtained from X-ray diffraction line broadening analysis (Warren-Averbach method) showed consistency with the results obtained for optical functions and agreed well with the predictions of both structural zone model (SZM) and effective medium approximation (EMA) results. Therefore, a direct correlation between the optical properties and the processes involved in the evolution of thin films is established. The optical data, in particular the conductivity results for sputter deposited Ti films show more agreement with those of bulk sample (Lynch et al., 1975), while those of UHV E. Gun deposited films are more consistent with those of thin film sample (Johnson and Christy, 1974). © 2010 Elsevier Ltd. All rights reserved.

Moradi O.,Islamic Azad University at Shahre Qods
Fullerenes Nanotubes and Carbon Nanostructures | Year: 2013

In this study, the adsorption behavior of Basic Red 46 (BR 46) in aqueous solutions by single-walled carbon nanotube (SWCNTs) and functionalized SWCNTs having covalent attachments of carboxylic group (SWCNT-COOH) surface as adsorbents were investigated. The adsorption equilibrium data were analyzed using various adsorption isotherms, and the results have shown that adsorption behavior of BR 46 could be described reasonably well by a generalized isotherm. Kinetic studies indicated adsorption of BR 46 by SWCNTs and SWCNT-COOH surfaces follows a pseudo-order model. The maximum adsorption capacities of BR46 by SWCNTs and SWCNT-COOH surfaces are reported at 298 K, 38.35 and 49.45 mg/g, respectively. The adsorption of BR 46 depends on the initial pH of the solution with maximum uptake occurring at about pH 9. Decrease in the absolute value of ΔG 0 with increasing temperature indicates that higher temperatures hardship the adsorption. The negative value of ΔH 0 reflects an exothermic adsorption and indicates that the adsorption is favored at low temperature. The negative entropy states that the adsorption of BR 46 by SWCNT-COOH and SWCNTs surfaces are orderly adsorbed by the surfaces. © Taylor & Francis Group, LLC.

Amani J.,Islamic Azad University at Shahre Qods | Musavi S.M.,University of Tabriz
Tetrahedron | Year: 2011

DFT calculations are employed to compare and contrast six-membered ring carbenes including 1,3-dimethyltetrahydropyrimidin-2-ylidene (1a), 1-methyl-3-cyclopropyltetrahydropyridine-2-ylidene (2a), and 1,3-dicyclopropylcyclohexane-2-ylidene (3a) as well as their unsaturated analogues 1b, 2b, 3b, and 2c. The amino groups exert singlet-triplet energy separation (Es-t) of 60.9 kcal/mol to 1a while cyclopropyls induce a Es-t of 14.8 kcal/mol to 3a. The simultaneous presence of amino and cyclopropyl in 2a leads to a Es-t of 43.3 kcal/mol. Unsaturation slightly increases the Es-t of 1a and 3a but not that of 2a. Our thermodynamic, kinetic, and reactivity results are compared with those of synthetic five-membered ring N-heterocyclic carbenes. © 2010 Elsevier Ltd. All rights reserved.

Moradi O.,Islamic Azad University at Shahre Qods
Chemical and Biochemical Engineering Quarterly | Year: 2011

In this studies removal of some ions such as Pb(II), Cd(II) and Cu(II) by single walled carbon nanotubes (SWCNTs) and carboxylate functionalized (SWCNTs-COOH) from aqueous solution were studied. The effect of pH, contact time, initial concentration, ionic strength, temperature, equilibrium, models and thermodynamic parameters on the removal of ions was investigated. The results indicated that Langmuir fits adsorption isotherm data better than Freundlich model. The results also demonstrated that SWCNTs-COOH can remove ions more effectively. Maximum adsorption capacities for Pb(II), Cu(II) and Cd(II) ions on SWCNTs-COOH were obtained as 96.02, 77.00 and 55.89 mg g -1, respectively and by SWCNTs, as 33.55, 24.29 and 24.07 mg g -1, respectively. Thermodynamic parameters values showed that the adsorption of ions on SWCNTs-COOH and SWCNTs at 283-313 K are spontaneous and endothermic. Further, adsorption of ions by SWCNTs-COOH and SWCNTs are chemisorption and physisorption processes, respectively.

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