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The paper deals with the development and simulation results of the switched reluctance motor for electric drive of mine battery electric locomotives instead of the DRT-14 DC motor. The switched reluctance motor parameters are obtained based on numerical calculation of the magnetic field by QuickField program and are embedded in MATLAB/Simulink model of a switched reluctance motor created for 8/6 magnetic system configuration. SRM-14-615 has the mechanical characteristics as DC motor DRT-14 and meets the required operating modes as part of the AM8D mine battery electric locomotive. Also two types of models using methods and techniques of the artificial intelligence theory are presented: a model with a fuzzy control system in the Fuzzy Logic Toolbox package and a model with a neural network control system in the Neural Network Toolbox package.

A novel molybdenum-free nitrate reductase was isolated from the obligate chemolithoautotrophic and facultative anaerobic, (halo)alkaliphilic sulphur-oxidizing bacterium Thioalkalivibrio nitratireducens strain ALEN 2. The enzyme was found to contain vanadium and haem c as cofactors. Its native molecular mass was determined as 195kDa, and the enzyme consists of four identical subunits with apparent molecular masses of 57kDa. Apart from nitrate, the enzyme can utilize nitrite, chlorate, bromate, selenate and sulphite as electron acceptors. Moreover, it also has a haloperoxidase activity.

Two catalytically distinct molybdenum‐free dissimilatory nitrate reductases, a soluble periplasmic and a membrane‐bound one, were isolated from the vanadate‐reducing facultatively anaerobic bacterium Pseudomonas isachenkoviiand purified to electrophoretic homogeneity. The enzymes did not contain molybdenum, the periplasmic enzyme contained vanadium, whereas the membrane‐bound enzyme was vanadium‐free. Both nitrate reductases lacked molybdenum cofactor. This fact was proved by reconstitution of the apoprotein of the nitrate reductase of Neurospora crassa nit‐1mutant. This is the first demonstration of molybdenum‐free and molybdenum cofactor‐free nitrate reductases.

Giant left atrium is a pathology that causes a lot of different complications, therefore it is very important to perform volume reduction. In some cases left atrium volume reaches a huge size. There are a lot of different methods for left atrium reduction: from wall plication, multicomponent resection followed by restoration integrity of wall to autotransplantation. In spite of the relative simplicity of plications and resection, these methods do not always allow to reduce left atrium to the desired volume. Cardiac autotransplantation is the most radical approach to the correction of giant left atrium which allows reducing left atrium including interatrial septum. The successful result of giant left atrium surgical treatment (volume of left atrium is 2200 ml according to the data of computerized tomography) by the method of autotransplantation is presented in the article.

Polarization characteristics can be measured for engineering CO2lasers by means of an instrument consisting of two rigidly fixed insulating plates combined with radiation detectors, which are placed in such a way that the planes of incidence form an angle of 90°. The plates with detectors rotate around the propagation direction in a cyclic fashion. The main flux passes through the plates, and only the reflected paris of the beam are used in the recording. The radiation prom an LN-1,2, NM-I1 laser is partially or completely polarized for about 70–80% of the time of operation. During the rest of the time, the radiation is unpolarized or there is an ongoing change in the orientation of the polarization plane. All the channels are at least partially synchronized in polarization characteristics.

The paper deals with a new design of a low-speed disk permanent magnet axial flux synchronous machine for decentralized power generation, which has improved weight-size parameters. In the new design the value of the air gap value is reduced by removing all inter-coil connections from the gap and also a concentrated winding with a high winding coefficient is applied. A two-rotor prototype of this design is created (150 W, 83 V, 250 rpm) and its magnetic circuit and the concentrated windings arrangement are described, as well as the results of the machine experimental study. The 2D finite element analysis is used to determine the effect of the air gap value effect on the disk slotless generator parameters. The method of rational choice of the machine main dimensions and the parameters of its winding according to nominal data and electromagnetic loads limitations are presented. Comparison of parameters and characteristics of a 20-pole-pair 5 kW synchronous wind generator with the new design and cylindrical one with tangential magnetization is performed. The proposed slotless design exceeds the cylindrical one in efficiency and requires less material costs. The limitations are the higher value of the outer machine diameter and the required large magnets mass.