All issues

The paper studies the determination for one of the dynamic quality parameter (PDK) of railway vehicles — car body lateral acceleration — by using of computer simulation system for railway vehicles dynamic Simpack Rail. This provide the complex simulation environment with variable velocity depending on the train schedule. The rail vehicle model of typical 1520 mm gauge fright locomotive section used for simulation has been verified by means of the chair “Electric multiple unit cars and locomotives” in the Russian University of Transport (RUT (MIIT)). Due to this homologation the questions of model creating and verification in preprocessor are excluded in this paper. The paper gives the detail description of cartographic track modeling in situation plane, heights plane and superelevation plane based on the real operating data. The statistic parameters (moments) for the rail related track excitation and used cartographic track data of the specified track section in this simulation are given as a numeric and graphical results of reading the prepared data files. The measurement of the car body residual lateral acceleration occur under consideration of the earth gravity acceleration part like the accelerometer measurement in the real world. Finally the desired quality parameter determined by simulation is compared with the same one given by a test drive. The calculation method in both cases is based on the middle value of the absolute maximums picked up within the nonstationary realizations of this parameter. Compared results confirm that this quality factor all the first depends on the velocity and track geometry properties. The simulation of the track in this application uses the strong conformity original track data of the test ride track section. The accepted simplification in the rail vehicle model of fright electric locomotive section (body properties related to the center of gravity, small displacements between the bodies) by keeping the geometric and force law characteristics of the force elements and constraints constant allow in Simpack Rail the simulation with necessary validity of system behavior (reactions).

The problem of ligand binding to certain receptor proteins is of central importance in cellular signaling, but it is still unresolved at a molecular level. In order to enhance our understanding of the molecular mechanisms we used a biophysical approach to study a serotonin-gated ion channel. The molecular model of 5-HT3 receptor extracellular domain was created using computer-based homology modeling. The docking method was used for building complexes of the 5-HT3 receptor and ligands. Some different activities were investigated by the method of molecular dynamics.

Here we demonstrate the results of kinetic modeilng of DNA double-strand breaks induction and repair and phosphorilated histone H2AX ($\gamma$-H2AX) and Rad51 foci formation in primary human fibroblasts exposed to low-LET ionizing radiation (IR). The model describes two major paths of DNA double-strand breaks repair: non-homologous end joining (NHEJ) and homologous recombination (HR) and considers interactions between DNA and several repair proteins (DNA-PKcs, ATM, Ku70/80, XRCC1, XRCC4, Rad51, RPA, etc.) using mass action equations and Michaelis–Menten kinetics. Experimental data on DNA rejoining kinetics and $\gamma$-H2AX and Rad51 foci formation in vicinity of double strand breaks in primary human fibroblasts exposed to low-LET IR with various dose rates and exposure times was utilized for training and statistical validation of the model.

The results of homology modeling of HydSL, a NiFe-hydrogenase from purple sulphur bacterium Thiocapsa roseopersicina BBS are presented in this work. It is shown that the models have larger confidence level than earlier published ones; a full-size model of HydSL hydrogenase is presented for the first time. The C-end fragment of the enzyme is shown to have random orientation in relation to the main protein globule. The obtain models have a large number of ion pairs, as well as thermostable HydSL hydrogenase from Allochromatium vinosum, in contrast to thermolabile HydAB hydrogenase from Desulfovibrio vulgaris.