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We investigate the influence of quenched disorder on the steady states of driven systems of the elastic interface with nonlocal hydrodynamic interactions. The generalized elastic model (GEM), which has been used to characterize numerous physical systems such as polymers, membranes, single-file systems, rough interfaces, and fluctuating surfaces, is a standard approach to studying the dynamics of elastic interfaces with nonlocal hydrodynamic interactions. The criticality and phase transition of the quenched generalized elastic model are investigated numerically and the results are presented in a phase diagram spanned by two tuning parameters. We demonstrate that in the one-dimensional disordered driven GEM, three qualitatively different behavior regimes are possible with a proper specification of the order parameter (mean velocity) for this system. In the vanishing order parameter regime, the steady-state order parameter approaches zero in the thermodynamic limit. A system with a nonzero mean velocity can be in either the continuous regime, which is characterized by a second-order phase transition, or the discontinuous regime, which is characterized by a first-order phase transition. The focus of this research is to investigate the critical scaling features near the pinning-depinning threshold. The behavior of the quenched generalized elastic model at the critical depinning force is explored. Near the depinning threshold, the critical exponent is obtained numerically.
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Here, we present results of numerical simulations and the scaling characteristics of one-dimensional random fluctuations with heavy-tailed probability distribution functions. Assuming that the distribution function of the random fluctuations obeys Lévy statistics with a power-law scaling exponent, we investigate the fractional diffusion equation in the presence of µ-stable Lévy noise. We study the scaling properties of the global width and two-point correlation functions and then compare the analytical and numerical results for the growth exponent ß and the roughness exponent α. We also investigate the fractional Fokker-Planck equation for heavy-tailed random fluctuations. We show that the fractional diffusion processes in the presence of µ-stable Lévy noise display special scaling properties in the probability distribution function (PDF). Finally, we numerically study the scaling properties of the heavy-tailed random fluctuations by using the diffusion entropy analysis. This method is based on the evaluation of the Shannon entropy of the PDF generated by the random fluctuations, rather than on the measurement of the global width of the process. We apply the diffusion entropy analysis to extract the growth exponent ß and to confirm the validity of our numerical analysis.
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In this paper, we investigate and develop an alternative approach to the numerical analysis and characterization of random fluctuations with the heavy-tailed probability distribution function (PDF), such as turbulent heat flow and solar flare fluctuations. We identify the heavy-tailed random fluctuations based on the scaling properties of the tail exponent of the PDF, power-law growth of qth order correlation function, and the self-similar properties of the contour lines in two-dimensional random fields. Moreover, this work leads to a substitution for the fractional Edwards-Wilkinson (EW) equation that works in the presence of µ-stable Lévy noise. Our proposed model explains the configuration dynamics of the systems with heavy-tailed correlated random fluctuations. We also present an alternative solution to the fractional EW equation in the presence of µ-stable Lévy noise in the steady state, which is implemented numerically, using the µ-stable fractional Lévy motion. Based on the analysis of the self-similar properties of contour loops, we numerically show that the scaling properties of contour loop ensembles can qualitatively and quantitatively distinguish non-Gaussian random fields from Gaussian random fluctuations.
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In this study, nanocrystalline Sn-doped In(2)O(3) (ITO) films were deposited by electron beam evaporation technique and were annealed in air atmosphere from 300°C to 500°C for 30 min. Then, the annealed ITO films in air at 450°C were reannealed in vacuum for 1 h at different temperatures from 300°C to 500°C. The effects of reannealing temperature on structural, electrical, and optical properties of the ITO films were investigated. Increasing reannealing temperature from 300°C to 500°C reduced sheet resistance of ITO thin films from 38 to 12(Ω/sq). The highest transparency over the visible wavelength region of spectrum (95%) was obtained for reannealed films at 450°C. The optimum reannealing temperature for these films is 450°C. Refractive index at 550 nm and porosity for ITO films reannealed at 450°C were 1.92% and 21.2%, respectively. The allowed direct bandgap at different reannealing temperature was evaluated to be in the range of 4.1-4.28 eV. X-ray diffraction results showed that the reannealed films were polycrystalline and a rise in grain size was observed in them. The average grain size in the films reannealed in vacuum at 450°C is about 48.6 nm. Atomic force microscope images indicated that the grain size and root-mean-square roughness films depend on the reannealing temperature. It has been found that reannealing temperature is a key factor in controlling the structural, electrical, and optical properties of ITO films. The power conversion efficiency of the device with ITO films reannealed at 450°C is 1.22% and it is about 58% higher than that of the device without it. This indicates that this film is a promising transparent electrode for organic photovoltaic cells.
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BACKGROUND: Electroconvulsive therapy (ECT) is one of the most efficacious treatment for major depressive disorder (MDD), it is also used as a rapid and efficacious treatment for other psychiatric disorders, especially treatment resistant ones. The cognitive impairment is one of the most important side effects of ECT. This study examined the Memoral herbal efficacy in prevention of ECT-induced memory impairment. METHODS: In a randomized clinical trial, 70 patients with mood disorders who were candidates for ECT enrolled in either Memoral or Control group, and received either Memoral or placebo. The memory was assessed by Addenbrook Cognitive Examination (ACE), and the findings were analyzed by ANOVA under SPSS18. RESULTS: The Memoral group patients showed significantly higher total ACE scores than placebo group (P < 0.001). The scores of attention and orientation, verbal fluency and memory subscales not only never decreased during the study in Memoral group, but also increased. There was no significant difference between these scores of Memoral and placebo groups for the subscales of language and visuospacial ability. CONCLUSION: The Memoral herbal is an efficacious and safe choice in prevention of ECT- induced cognitive impairment.