Sharif Digital Repository

This paper compares the Shuffling-Adaptive Neuro Fuzzy Inference System (Shuffling-ANFIS) with conventional ANFIS as the method for selecting the features of nonlinear systems. Shuffling-ANFIS technique uses the advantage of data splitting with the ANFIS as a powerful feature selection method to select the most important factors affecting nonlinear phenomena. In this technique, the features with the largest percent of frequency can be found by running the conventional ANFIS sequential forward search on the large number of training and test sets using leave-one-out validation criteria. The superiority of Shuffling-ANFIS over the conventional ANFIS was evaluated by using two synthetic and one... 

Hydrogen bonding interactions between thymine nucleobase and 2'-deoxythymidine nucleoside (dT) with some biological anions such as F - (fluoride), Cl - (chloride), OH - (hydroxide), and NO 3 - (nitrate) have been explored theoretically. In this study, complexes have been studied by density functional theory (B3LYP method and 6-311++G (d,p) basis set). The relevant geometries, energies, and characteristics of hydrogen bonds (H-bonds) have been systematically investigated. There is a correlation between interaction energy and proton affinity for complexes of thymine nucleobase. The nature of all the interactions has been analyzed by means of the natural bonding orbital (NBO) and quantum theory... 

In recent years, there has been increasing interest in damaged DNA and RNA nucleobases. These damaged nucleobases can cause DNA mutation, resulting in various diseases such as cancer. Alkylating agents are mutagenic and carcinogenic in a variety of prokaryotic and eukaryotic organisms. The present study employs density functional theory (DFT/B3LYP) with the 6-311++G(d,p) basis set to investigate the effect of chemical damage in O-alkyl pyrimidines such as O4-methylthymine, O2-methylcytosine and O 2-methylthymine. We compared the intrinsic properties, such as proton affinities, gas phase acidities, equilibrium tautomerization and nucleobase pair's hydrogen bonding properties, of these... 

Interaction of the DNA thymine base with Cu+ and Zn3+ was studied to explore: a) The metal binding energy (MIA) of thymine with Cu+ and Zn2+ and b) The possible correlation between charge transfer and MIAs. The gas-phase Cu+ and Zn2+ affinities of thymine, as well as the Mulliken charges, on the complexed metal cations were both determined at the same computational level, including the density functional level and employing the hybrid B3LYP exchange correlation potential in connection with the 6-311++G (d,p) basis set. All the molecular complexes were obtained by interaction between the most stable tautomer of thymine and two transition mono and divalent (Cu+, Zn2+) metal ions. To probe all...