Rotational analysis of naphthol-aromatic ring complexes stabilized by electrostatic and dispersion interactions

For complexes involving aromatic species, substitution effects can influence the preferred geometry.

Formation of carnosine - an ab initio study

Formation of carnosine from histidine and b-alanine is studied by ab initio MO-LCAO-SCF method followed by the perturbative configuration interaction (MP2) in vacuo. After the full geometry optimization at the SCF level, the molecular properties were evaluated and followed by the vibrational-rotational analysis. Consequently, the energy, entropy and free energy were evaluated for the reactants and products of the reaction histidine + beta-alanine = carnosine + H2O and finally the equilibrium constant was enumerated.

Nonlinear vibrational and rotational analysis of microbeams in nanobiomaterials using Galerkin decomposition and differential transform methods

In this paper, a nonlinear vibrational and rotational analysis of microbeams in nanobiomaterials using Galerkin Decomposition (GDM) and Differential Transform Methods (DTM) is presented. The dependency of cell migration and growth on nanoscaffold porosity and pore size architecture in tissue regeneration is governed by a dynamic model for the nonlinear vibration and rotation of the microbeams of nanobiomaterials and represented by a set of nonlinear partial differential equations. The solutions of the governing model are obtained by applying GDM and DTM and good agreement is achieved with numerical Runge-Kutta method (RK4). From the results, it is observed that an increase in Duffing term resulted in the increase of the frequency of the micro-beam. An increase in the foundation term also resulted in a corresponding increase in the frequency of the system for both free and forced dynamic responses. This study will enhance the application of tissue engineering in the regeneration of damaged human body tissues.

Rotational analysis of ChaCha permutation

<p style='text-indent:20px;'>We show that the underlying permutation of ChaCha20 stream cipher does not behave as a random permutation for up to 17 rounds with respect to rotational cryptanalysis. In particular, we derive a lower and an upper bound for the rotational probability through ChaCha quarter round, we show how to extend the bound to a full round and then to the full permutation. The obtained bounds show that the probability to find what we call a parallel rotational collision is, for example, less than <inline-formula><tex-math id="M1">\begin{document}$ 2^{-505} $\end{document}</tex-math></inline-formula> for 17 rounds of ChaCha permutation, while for a random permutation of the same input size, this probability is <inline-formula><tex-math id="M2">\begin{document}$ 2^{-511} $\end{document}</tex-math></inline-formula>. We remark that our distinguisher is not an attack against the ChaCha20 stream cipher, but rather a theoretical analysis of its internal permutation from the point of view of rotational cryptanalysis. Whenever possible, our claims are supported by experiments.</p>