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The experience of modification of ore-thermal production is described. A rectangular furnace is replaced by a round ore-thermal furnace at a retained power supply, namely, a three-phase furnace transformer with star-connected terminals. Unique design solutions are proposed to achieve the maximum possible level of introduced useful power and the minimum inductive reactance of the secondary current lead.

Background This study evaluated the effectiveness of treatment with an indapamide/amlodipine single-pill combination (SPC) in outpatients with uncontrolled isolated systolic hypertension (ISH) aged over 55 years in real-life clinical practice. Methods This was a post-hoc analysis of the subgroup of patients with ISH from ARBALET, a 3-month, multicenter, observational, open-label study conducted in Russia among patients with grade I or II hypertension who were either uncontrolled on previous antihypertensive treatment or treatment-naïve. The effectiveness of indapamide/amlodipine SPC was assessed by the change in office systolic blood pressure (SBP) and the rate of target SBP ( Results The ARBALET study recruited 2217 patients, of whom 626 had ISH and were included in this post-hoc analysis (mean age 66.1 ± 7.8 years; 165 men [26.4%] and 461 women [73.6%]). Target SBP Conclusion This post-hoc analysis of the observational ARBALET study showed that indapamide/amlodipine SPC was associated with significant reductions in BP and high rates of target BP achievement in a broad age range of patients with ISH treated in routine clinical practice. Study registration number ISRCTN40812831.

A modern technique is proposed to calculate the electrical parameters of the characteristic sections of the power-supply circuits of ore-smelting furnaces, namely, laminated stacks, flexible part, and tubular busbars of the power-supply circuit of an electrode. This technique is based on the results of numerical simulation of the electromagnetic field of a set of conductors with the ANSYS software package and on a mathematical model for calculating the inductance of a system of two rectilinear conductors arbitrarily located in space.

Electric currents of the order 100 kA flow in secondary current leads of powerful electrotechnological installations. It causes active power losses and electromagnetic field power dissipation. To improve engineering-and-economical performance it is necessary to minimize pure resistance and inductance of current lead and symmetrize the parameters over phases while designing the installation. The paper considers approaches to formulate modern method for calculation pure resistance and inductance of secondary current leads in powerful electrotechnological installations.Interleaved conductors' packages have been examined as the longest partition of secondary current leads in ore-thermal furnace. The examination was carried out with numerical simulation of electromagnetic field of groups of interleaved water-cooled tubular buses (bus-packages) in ANSYS software. Dependencies of bus-packages pure resistance and inductance and their geometric parameters and interleaving ways for magnetic flux compensation have been obtained. Analysis of obtained results allows defining empiric formulae for calculation of electrical parameters of interleaved packages in powerful electrotechnological installations.

While designing an ore-thermal furnace it is necessary to minimize and balance its secondary current contact jaw electrical parameters. The study deals with the method of calculating pure resistance and inductance of ore-thermal furnace electrode holder tubes. It is significant because the tubes have complicated wires configuration and their resistance is noticeable in current contact jaw total impedance because of the same half-phase currents flow in tube bundles and absence of magnetic flux compensation. Real bent wires are suggested to be approximated by broken lines. After that both existing and proposed by the authors formulas can be used for calculating inductance and mutual inductance of two straight-line wires arbitrary placed in space. Current distribution non-uniformity along separate tubes is taken into account in an iterative algorithm. Currents in wires are assumed to be equal at the first iteration. Then they are corrected at following steps of the iteration algorithm with respect to wires resistances calculation results. Skin effect and closure effect between wires segments are taken into account when pure resistance is calculated. The proposed method has been applied in the development of the software for calculating ore-thermal furnace secondary current-contact jaw electrical parameters. The method has been approbated in the design of the 60 MVA ore-thermal furnace made by ZAO “Electroterm”, Novosibirsk, Russia. The results obtained have been tested with numeric 3D models created in ANSYS environment. Inductance calculation error is 10%, pure resistance error is 25%.

This article is devoted to solving the electrical engineering problem of using an ore-thermal furnace (OTF) as the main ferroalloy industrial unit. The secondary current jaw of such a unit should have minimal active resistance and inductive reactance, as well as balanced phase current jaws. The operating currents in OTF electrodes can exceed 100 kA. These currents are distributed between parallel wires. The rigid stationary current jaw from the transformer to the flexible current jaw is set up as a package of rectangular or tubular bus bars. According to the most frequently used current jaw scheme, electrodes carry the linear currents. Hence, bus package inductance can be reduced by interleaving the half-phase wires. There are many variants of interleaved package construction design. To select one of them, it is convenient to have a simple method for determining the active resistance and reactance values of bus packages. The power source position to one side of the furnace tank causes a significant difference between the phase bus package lengths, which leads to the total secondary current jaw unbalance. This unbalance involves noninform power dissipation in the OTF operating space and, therefore, a decrease in the OTF performance characteristics. The relationships between the bus package active resistance and reactance values and their geometrical parameters with different ways of interleaving are studied by the method of numerical simulation. Simple formulas for calculating the electrical parameters of bus packages and finding structural solutions providing a balanced current jaw are obtained.

The paper describes experience of reconstruction ore-thermal plant by replacement a rectangular ore-thermal furnace to circular one while keeping same power source — three-phase furnace transformer with star-connected outputs. Original constructive decisions were made to provide minimal inductance of secondary current lead and maximal useful power input.

Based on the numerical modeling in an ANSYS system, the dependences of electrical parameters of laminated stacks with rectangular and tubular sections on their geometrical parameters, relative position, and method of unblading are obtained. Investigations are carried out in order to develop a new method for calculating the resistance and inductive reactance of laminated stacks for ore-smelting electric furnaces.

The description of a mathematical model and software for calculating the secondary current conductances of three-phase electrotechnological installations are presented. The results of calculations of the secondary circuit inductance for ultrahigh-power arc furnaces are compared with the experimental data.

The paper describes new method of calculation for active and inductive resistance of split interleaved current leads packages in ore-thermal electric furnaces. The method is developed on basis of regression analysis of dependencies of active and inductive resistances of the packages upon their geometrical parameters, mutual disposition and interleaving pattern. These multi-parametric calculations are performed with ANSYS software. Proposed method allows solving problems of minimization and balancing of electrical parameters of split current lead in ore-thermal furnaces.

The aim of the study was to assess the quality of endodontic therapy and estimate further treatment needs. Nine hundreds orthopantomograms of 442 men and 458 women (aged 18-70) without any clinical manifestations of endodontic pathology were examined. In 1170 patients (41%) additional intraoral radiographs were taken to assess the periapical status. 2852 (13.8%) of the 20 724 teeth examined had periapical lesions and/or root fillings. 2503 of the 2853 teeth were endodontically treated, only 1011 of them (40.4%) having all their root canals obturated. 612 (41.3%) of the 1492 (59.6%) teeth with inadequate root canal fillings had no signs of apical periodontal lesions. Of the 1229 teeth needing a root canal treatment 349 required primary treatment, 880 required retreatment.

The regulation of free cytoplasmic calcium in HeLa cells was studied using a fluorescent calcium indicator into 1. It is found that addition of histamine caused substantial increase in calcium level. In calcium-free medium the increase was much smaller, implicating both intra- and extracellular calcium as sources of observed Ca2(+)-rise. Protein kinase C activator, phorbol myristate acetate, completely blocked the effect of histamine. Agents causing rise in cellular cAMP level did not change the Ca2(+)-rise.

Postobturation pain of different origin after endodontic treatment was studied in 100 patients after treatment of 151 teeth with filling of 264 channels. 34.4% patients complained of pain. The incidence and intensity of pain were scored. Postobturation pain clearly depended on the number of treatment sessions, number of channels filled in one tooth, and excessive filling "beyond the apex". The method of "crown down" preparation using completely rotating profile instruments and GT rotary files proved to be most effective as regards prevention of postoperative pain.

It was shown that amiloride, orthovanade and uabain induced almost a two-fold decrease in the rate of incubation medium oxidation by the chick embryo fibroblasts due to the Na+/H+ exchange and inhibited by more than 95 per cent the influenza virus activity. The following mechanism for inhibition of the influenza virus multiplication in the cells under the effect of the above mentioned substances was proposed: suppression of the cellular Na+/H+ exchange responsible for the decrease in pH value in the virus-carrying endosomes----prevention of the decrease in the intraendosomal pH value to the critical level----blocking of the acid dependent process of the virus uncoating----inhibition of the influenza infection as a whole.

Remantadine has been shown to induce a decrease in acidification rate of incubation medium by chick embryo fibroblasts, caused both by Na+/H+ exchange and diffusion of lactic acid, the final product of glycolysis. The degree of acidification rate decrease grew with increasing concentration and time of cell incubation with preparation. Possible implementation of the inhibitory effect of remantadine on acid-dependent process of influenza virus uncoating by decreasing cellular Na+/H+ exchange and glycolysis is discussed.