Electronic, dielectric and optical properties of two dimensional and bulk ice: a multi-scale simulation study

The intercalated water into nanopores exhibits anomalous properties such as ultralow dielectric constant.~Multi-scale modeling and simulations are used to investigate the dielectric properties of various crystalline two-dimensional ices and bulk ices. Although, the structural properties of two-dimensional (2D-) ices have been extensively studied, much less is known about their electronic and optical properties. First, by using density functional theory (DFT) and density functional perturbation theory (DFPT), we calculate the key electronic, optical and dielectric properties of 2D-ices. Performing DFPT calculations, both the ionic and electronic contributions of the dielectric constant are computed. The in-plane electronic dielectric constant is found to be larger than the out-of-plane dielectric constant for all the studied 2D-ices. The in-plane dielectric constant of the electronic response is found to be isotropic for all the studied ices. Secondly, we determined the dipolar dielectric constant of 2D-ices using molecular dynamics simulations (MDS) at finite temperature. The total out-of-plane dielectric constant is found to be larger than 2 for all the studied 2D-ices. Within the framework of the random-phase approximation (RPA), the absorption energy ranges for 2D-ices are found to be in the ultraviolet spectra. For the comparison purposes, we also elucidate the electronic, dielectric and optical properties of four crystalline ices (ice VIII, ice XI, ice Ic and ice Ih) and bulk water

Tight-Binding Studio: A Technical Software Package to Find the Parameters of Tight-Binding Hamiltonian

We present the Tight-Binding Studio (TBStudio) software package for calculating tight-binding Hamiltonian from a set of Bloch energy bands obtained from first principle theories such as density functional theory, Hartree-Fock calculations or Semi-empirical band structure theory. This will be helpful for scientists who are interested in studying the electronic properties of structures using Green's function theory in tight-binding approximation. TBStudio is a cross-platform application written in C++ with a graphical user interface design that is user-friendly and easy to work with. This software is powered by Linear Algebra Package C interface library for solving the eigenvalue problems and the standard high-performance OpenGL graphic library for real-time plotting. TBStudio and its examples together with the tutorials are available for download from tight-binding.com

Assessment of human errors in driving accidents; Analysis of the causes based on aberrant behaviors

Introduction: Today, mortalities and injuries due to traffic accidents have been confirmed as a global phenomenon. Meanwhile, mistakes and high risk behaviors by drivers, is the most important intervening factor in traffic accidents. This study is to analyze the causes of traffic accidents according to drivers' aberrant behaviors. Methods: This cross-sectional study was conducted on 540 taxi drivers using Manchester Driving Behaviour Questinnaire in 0-5 Likert scale. After being gathered, the data were analyzed by SPSS 11.5 using Pearson Correlation and Logistic Regression. Findings: The mean score of aberrant driving behaviors was obtained 2.06 (± 0.47) and lapse obtained the highest score and driving mistakes did the lowest. As age advanced, the rate of aberrant behaviours declined (P = 0.006). Commitment of mistakes and offences was more prevalent in ages under 30 years compared to other age ranges and lapse in the individuals over 50 years was more prevalent compared to other items. The results of logistic regression indicated that all variables of DBQ are important in predicting Iranian drivers' aberrant behaviors (P < 0.001), but intentional offences had the highest correlation. There was an inverse correlation between driving history and intentional offences and mistakes (P < 0.001). Conclusion: According to the results, it could be said that intentional offences and lapse in driving behaviors are more predictive of self-reported accidents compared to other variables. The drivers in low ages are more willing to practice aberrant behaviors due to lack of adequate skill and experience and having intrinsic excitements. By contrast, as age advances, intentional offenses declines and the rate of lapses ascends. It seems that through provision of regular, periodic training for the drivers by occupation and creating awareness, aberrant behaviors and, by extension, traffic accidents could be effectively decreased

The Pragmatic Instruction Effects on Persian EFL Learners’ Noticing and Learning Outcomes in Request Forms

This study investigates the request strategies used by Persian learners of English as a Foreign Language (EFL), aimed at exploring the pragmatic instruction effects on their noticing constrained by different types of treatment tasks. The subsequent effect of the learners’ noticing on their learning outcomes is taken into account as well. Thirty learners were divided into two instructional (treatment) conditions: a form-comparison condition and a form-search condition. Discourse completion tests were used to generate data related to the request strategies used by each group in pre- and posttests. The treatment data were examined regarding the extent to which the learners had noticed the appropriate manner of request realization in English and were further compared with the posttest. The findings revealed that during the treatment, the amount of learners’ noticing the target request forms in the form-comparison condition was greater than the form-search condition. Furthermore, learners’ higher awareness of the target request forms in the form-comparison condition could lead them to have a better performance in their posttest

A New Approach to Nonsinusoidal Steady-State Power System Analysis

A new analysis method using wavelet domain for steady-state operating condition of power system is developed and introduced. Based on wavelet-Galerkin theory, the system components such as resistor, inductor, capacitor, transmission lines, and switching devices are modeled in discrete wavelet domain for the purpose of steady-state analysis. To solve system equations, they are transferred to wavelet domain by forming algebraic matrix-vector relations using the wavelet transform coefficients and the equivalent circuit is thus built for system simulation. After describing the new algorithm, two-case studies are presented and compared with the simulations in the time domain to verify the accuracy and computational performance

Gate control of sensory neurotransmission in peripheral ganglia by proprioceptive sensory neurons

Melzak and Wall's gate control theory proposed that innocuous input into the dorsal horn of the spinal cord represses pain-inducing nociceptive input. Here we show that input from proprioceptive parvalbumin-expressing sensory neurons tonically represses nociceptor activation within dorsal root ganglia. Deletion of parvalbumin-positive sensory neurons leads to enhanced nociceptor activity measured with GCaMP3, increased input into wide dynamic range neurons of the spinal cord and increased acute and spontaneous pain behaviour, as well as potentiated innocuous sensation. Parvalbumin-positive sensory neurons express the enzymes and transporters necessary to produce vesicular GABA that is known to be released from depolarized somata. These observations support the view that gate control mechanisms occur peripherally within dorsal root ganglia