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The objective was to evaluate the effectiveness of the erector spinae plane block (ESP-block) as a component of perioperative analgesia in endovideosurgical hernioplasty of inguinal hernias.Materials and methods. The study included 70 patients who underwent endovideosurgical plastic surgery of inguinal hernias. All patients randomly divided into the main (n=32) and control (n=38) groups, were given general combined anesthesia. In the main group, it was supplemented with the ESP-block, which was performed with ropivacaine at the L1 level. Intraoperatively, fentanyl was used for analgesia. The indication for its introduction was an increase in the Surgical Pleth Index (SPI) of more than 50. In the early postoperative period, ketoprofen and tramadol were used for analgesia, which were administered with the development of moderate and high intensity of the pain. The effectiveness of the ESP-block was evaluated by comparing the total doses of analgesic drugs that were required for analgesia during surgery and in the early postoperative period in patients of both groups.Results. In the main group, the total doses of fentanyl and ketoprofen were statistically significantly lower compared to the control group (pn=15), the pain syndrome developed only 12 hours after the end of the surgery. Their intraoperative need for fentanyl did not differ from other patients of the main group (p>0.05).Conclusion. In endovideosurgical hernioplasty of inguinal hernias, the use of the ESP-block as part of multimodal analgesia contributes to achieving a good level of analgesia both intra- and in the early postoperative period.

Introduction. The purpose of the study is to develop measures determined by the strategic programmes for the development of Russian railway transport based on the analysis of power supply schemes for the traction network of the Far Eastern Railway, a branch of Russian Railways.Materials and methods. Evaluation of the performance of the traction power supply system was made based on the analysis of the actual performance of the Far Eastern Railway section, as well as the theories of electrical engineering and power supply of the 25 kV AC electrified railway system.Results. Based on the analysis of the joint operation of the external and traction power supply systems of the Far Eastern Railway, four traction substations with low technical and economic indicators were identified. Network sections that feed the substations are a bottleneck in the traction power supply system. It is proposed to increase the efficiency by switching the connection of the windings of transformers of traction substations to the systems of external and traction power supply according to the typical star – delta scheme. Such a connection will ensure an increase in the speed of trains, a reduction in train succession time and losses of electricity, an increase in the quality of electric energy in the external power supply system and electric networks of the Far Eastern Directorate for Energy Supply (a structural subdivision of Transenergo, a branch of Russian Railways).Discussion and conclusion. Normalisation of the connection of four traction substations according to the feeding scheme is ensured by changing the phasing in such a way that the power supply of the two legs of one winding of the power transformer is transferred to two windings. Alignment of the current modules in the windings of transformers of traction substations makes it possible to reduce the voltage drop in the most loaded phase and, accordingly, increase the voltage in the traction network, which ensures an increase in the speed of trains and a reduction in passing intervals. Switching the power supply of the arms from one winding of the transformer to two reduces the loss of electrical energy in power transformers and the external power supply system. Reducing the current unbalance in the windings of the power transformer improves the quality of electrical energy in the system of external and district power supply. An increase in the service life of the power transformer is ensured by a decrease in the intensity of thermal wear of the insulation of the most loaded winding.

Neurogenic pulmonary edema is one of the complications of acute cerebral diseases and traumas and it is accompanied by severe respiratory failure. It is associated with a high mortality level. There are several theories about neurogenic pulmonary edema development. The theory of the double hit is the most recent causing significant discussion. The theory is based on the pulmonary injury due to systemic inflammatory response when the glial tissue of the injured brain becomes the source of inflammatory mediators. A similar pathogenesis allows considering neurogenic pulmonary edema to be one of the forms of acute respiratory distress syndrome. It has diagnostic criteria common with acute respiratory distress syndrome, which are identified during acute cerebral injury and not associated with the other etiological factors. Currently, there are no effective prevention and treatment of neurogenic pulmonary edema. Support of respiratory exchange through artificial pulmonary ventilation is a major tool used for its management, which is recommended to be performed in compliance with protective ventilation principles. And some particular approaches of the preventive ventilation can be applied only with neuromonitoring.

The authors analyzed 60 clinical cases of follow-up study of patients aged 14 to 76 years old with otorhinosinusogenic intracranial complications and sepsis. Diseases of ENT organs were as the primary foci of infection-inflammatory processes. There were noted otitis media in 24 (40%) patients, rhinosinusitis - in 19 (31,7%) patients, combined purulent lesions of the middle ear and paranasal sinuses - in 17 (28,3%) patients. Purulent meningitis was diagnosed in 22 (46,7%) cases, purulent meningoencephalitis - in 38 (63,3%) patients. All treated patients were diagnosed with sepsis, including severe sepsis with multiple organ failure in 27 (45%) patients. The lethality consisted of 44,5% in group of patients with severe sepsis. The early diagnostics of systemic inflammatory response, sepsis, organosystemic disorders, practical application of modern algorithm of diagnostics and treatment, medico-economic standards of sepsis are necessary in order to start specialized intensive treatment on time. The patients should be transferred to septic center. Modern surgical and therapeutic methods must be applied. These approaches to treatment have a direct impact on the prognosis and outcome in each clinical case.

The authors investigated the epidemiological and clinical features of otogenic and rhinosinusogenic intracranial complications in East-Siberian region of Russian Federation. The rate of intracranial complications consisted of 0,2±0,1% in patients of ENT hospitals in Sakha- Yakutia, Krasnoyarsk Territory, Irkutsk Region, Republic of Tuva. The intracranial inflammatory pathology of otogenic nature was diagnosed two times more frequent than rhinosinusogenic. Meningitis was revealed at the same rate as lesions of brain substance (encephalitis, epi- and subdural abscesses). The high clinical efficacy was shown in surgical treatment of purulent polysinusitis using W. Messerklinger method of functional endoscopic rhinosinusosurgery (FESS). The method of transtemporal incision and drainage of otogenic abscess of the brain temporal lobe has a number of essential defects, because of them, the indications for application of this method should be considered and specified. It is necessary to have an interdisciplinary approach and use the modern achievements of medical science in order to develop the efficacy of treatment of given category of patients.

Producing of safer products by applying high pressure on biosystem, is a novel non-thermal technology with significant results in maintaining the natural characteristics of the food items. Modeling of the microorganism kinetics inactivation by the high pressure was determined and certificated by an experimental approach. It is established that the basic laws of the joint influence of the factors of high pressure, temperature and process time on microorganisms and vitamin C are reproduced in the framework of the linear kinetics. By choosing the values of the process parameters (pressure, temperature, duration of the process), the averaged thermodynamic characteristics of micro flora can be changed, as well as the value of the activation barrier of the biochemical reaction. Based on these results, working 40 min at the pressure 400 MPa, and temperature 300 K, the microorganism activity is minimum, and the vitamin C contain is preserved about 90 percent.

The sharply higher demand for uranium for nuclear power during 2010–2050 and possibilities of modern mineral-material resources to meet these needs are evaluated on the basis of an analysis of IAEA information and other publications. Forecasts to 2030 show adequate reserves and resources for producing the required amount of uranium. New deposits will supply production expansion beyond 2030.

Results are reported from a comprehensive test, under real conditions, of technology for removal of 90Sr from the waters of the Techa reservoir cascade. This technology includes stages of preliminary decontamination, ion exchange softening with desorption and carbonate precipitation of hardening salts and 90Sr from the desorbates, sorption cleanup on natural zeolites, and concentration of the strontium-containing carbonate precipitates. After the precipitates are removed, the solutions are reused in the desorption stage. The quality of the decontaminated water meets all the requirements for discharge into open drainage network in terms of all indicators. (The specific activity of 90Sr is 3–5 Bq/liter in the filtrates.) The 90Sr is concentrated by a factor of about 900 as solid radioactive waste in the form of a sediment with a moisture content of 50% and by about 1700 as air-dried solids. As a preliminary estimate, the operating cost of decontaminating 1 m3 of water in the V-11 reservoir is 200 rubles.

The prospects for supplying zirconium and hafnium-the main structural and prospective absorbing material for thermal reactors-are examined in accordance with the strategy for the development of nuclear power in our country up to 2030. The present situation concerning the use of Russian nuclear fuel is described. The characteristics of the main zirconium alloys used in domestic and foreign thermal reactors and the approximate requirements for baddeleyite and zirconium concentrates, the distribution of balance zirconium reserves, and the requirements of the nuclear industry for hafnium metal and hafnium compounds are presented.

The physicomechanical methods of separation of conventional mineral raw materials, including uranium-containing stock, can be used successfully to decontaminate soils and remediate territories contaminated by mining companies. Using its many years of scientific and applied experience in the development and commercial adoption of technology for reprocessing uranium-containing raw materials, the All-Russia Research Institute of Heat Sources is restoring radioactively contaminated territories within the Russian Federation and the Commonwealth of Independent States. The results of investigations of the decontamination of contaminated soils and territories, including radiometric separation, fine classification in hydrocyclones, and magnetic separation, are described. Effective technological schemes and their hardware implementation have been developed.

A method of sorption extraction of uranium from solutions and pulps containing macroscopic and trace impurities by anionites with gel or porous structure has been developed. An anionite saturated in the initial solution or pulp is treated with a solution of an alkaline agent, to which an alkaline-metal salt is added, and is presaturated with uranium in a period of 2–5 h in contact with a commercial-grade desorbate.

Information concerning the development and performance of environmental protection work and measures for guaranteeing the safety of the production operations conducted at the All-Russia Scientific–Research Institute of Chemical Technology is presented. Data on monitoring the adherence to the norms and standards concerning environmental protection at the industrial site of the institute, the dust-gas emission volumes, and the quantity and quality of discharged waste waters are examined. The results of radiation monitoring of the air, waste waters, snow, storm waters, and soil and decontamination and rehabilitation of territories are presented.

The mobile modular installation for processing of liquid radioactive waste of complex physic-chemical composition is developed in co-operation of the All-Russian Research Institute of Chemical Technology and a number of research and production organisation. The complex treatment of the solutions is done in a membrane adsorption technology followed by the cementation of formed sediments and slimes. The distinctive feature of the proposed LRW processing scheme is the ability to nearly completely extract the most dangerous radionuclides Cs- 137, Co-60 and Sr-90 on the selective inorganic Co-, Ni-,Cu-containing adsorbents at the stage of the initial solution pre-cleaning. The developed scheme on ensures a possibility of reusing purified water according to standard OST V95.823-89 and the minimum quantity of SRW ensuing at the LRW processing.

The method used to develop sorption-extraction processes in uranium hydrometallurgy over the last 50 years is examined. The first-generation sorption-extraction processes, ionites, and apparatus are described. Data for the second-generation sorption-extraction technology and improvement of apparatus are generalized. The third generation of these processes is characterized by the adoption of porous anionites AM-p and AMP-p in order to make the kinetic characteristics of the sorption and extraction processes closer to one another, by sorption leaching of uranium ores, and by adoption of double synergetic mixtures of extracting agents at the stage of repurification of the commercial reclaim and by the development of fast sorption processes for extracting uranium from productive solutions used in mound and underground leaching. The fourth-generation processes are characterized by the use of high-volume vinyl pyridine ionites, tertiary synergetic mixtures at the extraction stage, combined extraction-desorption processes, solid-phase regeneration of saturated ionites, and conversion of absorbed anions of uranyl-trisulfate into nitrate and chloride complexes. 1 figure.

Under the new economic conditions, the problem of decreasing substantially the cost of uranium in the final product obtained by processing mined ores has become acute. A search has shown that the problem can be successfully solved by closely combining hydrometallurgical conversion in plants with inexpensive processes, such as large-batch sorting in radiometric monitoring stations, radiometric piecewise separation, and mound leaching of low-grade ore. Radiometric enrichment produces tailings as well as average and rich concentrates. The rich concentrate will be processed using a separate scheme without a sorption process. A specific example of the combined scheme and the apparatus developed for implementing this scheme are examined. 1 figure, 3 tables, 10 references.

The characteristics of BaF2 barium fluoride crystals, grown from the materials provided by manufacturers, were investigated. The parameters which are important for application of the crystals in low-energy physics, electromagnetic high-energy calorimeters for detecting γ rays and electrons, and measurement of energy in the maximum possible range from tens of MeV up to hundreds of GeV, as well as applications in medicine, instrument building, geology, and so on, were measured. 7 figures, 3 tables, 13 references.

Sorption-extraction processes for obtaining finished coproducts during processing of uranium ores with valuable components, such as Mo, V, W, Re, Au, Sc, rare-earth elements, Y, Cs, Cu, Ta, Nb, Zr, Hf, Mn, Sn, and Se, are described. Special attention is focused on experience in extraction decontamination of phosphoric acid with its uranium and thorium content decreased by a factor of 20 and obtaining from it ecologically pure phosphate fertilizers and feed phosphates.

The separation coefficients of ZrF4(HfF4) and metal fluoride impurities in the process of vacuum sublimation between 900 and 1200 K in the molecular vaporization regime were calculated. The separation coefficients were found to decrease in the order CrF2> MnF2> NiF2> CoF2> MnF3> FeF2> AlF3> CrF3> CuF2> FeF3 . The conditions for purification of ZrF4and HfF4by vacuum sublimation were optimized. The total impurity content in both fluorides was found to increase with the product of the evaporation rate per unit area and the degree of evaporation. Fe was found to be the most difficult-to-remove impurity in ZrF4and HfF4 . The production rate of the sublimating plant is about 100 kg/year of ZrF4and HfF4sublimates. ZrF4was used to prepare optical fibers for laser applications and noncontact fiber sensors for monitoring the composition and temperature of liquid radioactive waste. Fluorohafnate glasses were used to fabricate radiation-resistant scintillating modules of dimensions 20 × 30 × 150 mm, weighing ≤0.5 kg.

Experimental work on transferring compact weapons plutonium by pyrochemical methods into its compounds was generalized. Powdered plutonium dioxide was obtained by interaction with moist air at 480–500°C. PuH3 was synthesized by interaction of the metal with hydrogen at 280°C. PuF3 was formed in an interaction of dioxides with HF and H2. The reaction of plutonium hydride with HF also resulted in plutonium trifluoride. PuF4 was synthesized by interaction of PuO2 with HF. In summary, compact plutonium can be transfered by water-free methods into its powdered compounds, which can be used in investigations for developing new types of fuel elements for power reactors. 6 figures, 2 tables, 16 references.

The scientific-research work on reprocessing spent oxide fuel by gas-fluoride method is reviewed. The refining possibilities of the basic stages of gas-fluoride technology are studied. The possibility of separating most fission products from the ashes at the fluoridation stage is confirmed experimentally. The use of fluoride sorbents (NaF, BaF2) permits reaching a total coefficient of removal of fission products from UF6 at the 107 level. It is shown that deep extraction of plutonium from oxide fuel is possible. The results of investigations on pyrohydrolysis of UF6 and a mixture of UF6 with PuF6 with production of granulate of the oxides with the required density with fluorine content 0.005 mass % and oxygen coefficient 2–2.1 are presented.

Systematic investigations were performed of the intensification of ion-exchange processes for extracting uranium from solutions and pulps during processing of polymetallic mineral stock. The crux of the process developed consisted in creating conditions under which polymer forms of uranyl are formed in solution and in the ionite phase. Several types of sorbents were studied. It was shown that the sorption characteristics were improved, and the optimal conditions for the process were determined. The character of the polymerization transformations of uranyl ions in the sorbent phase was determined. 5 figures, 11 references.

IR spectroscopy was used to identify and study the structure and properties of domestic and foreign samples of ionites synthesized for the nuclear industry. The mechanism of uranium absorption from complex salt solutions and the interaction of uranium with functional groups of ionites were investigated. The changes in the structural and chemical properties of ionites subjected to prolonged commercial use were estimated. The dependence of the process of uranium sorption on anionites and the dynamics of accumulation of silicon compounds in the anionites were found. A comparative analysis of the data showed that the capability of an anionite to absorb silicon does not always interfere with uranium sorption. 6 figures, 2 tables, 9 references.

The ecological problems arising in open-pit and underground production of solid-mineral deposits are described, the basic advantages of underground leaching, the reasons and sources of contamination of the environment during production of the deposits by underground leaching, and measures for protecting the air, soil, and surface and underground waters, and methods for rehabilitating underground waters are presented. Investigations of natural and artificial neutralization of waste underground-leaching solutions during the interaction of the solutions with technogenically unchanged rocks, performed at one of the uranium deposits, are described. An ecological monitoring scheme is proposed for the Khiagdin deposit.

The characteristics of various methods of desorption of uranium and other valuable impurities with ion exchangers, saturated in the sorption cycle, are presented. It is shown that the desorption methods developed give the maximum yield of metals in the output desorbate and simultaneously substantially decrease the impurity content in the finished product.

Almost 50 years of work at the All-Russian Scientific-Research Institute of Chemical Technology on the hydrometallurgy of uranium is surveyed. Autoclave leaching, sorptional pulp processing, and extractional deposition of pure uranium compounds permit the processing of lean uranium ores. Advanced low-waste technologies have been developed, with radical reconstruction of the processing plants.

A theory of general boundary-value problems is developed for differential operators with symbols not necessarily satisfying the Atiyah-Bott condition that the corresponding obstruction must vanish. A condition ensuring that these problems possess the Fredholm property is introduced and the corresponding theorems are proved.

In the paper we present a method of investigation of asymptotic behavior of solutions to parameter-dependent degenerate differential equations both with regular and irregular points of singularity. We examine the confluence phenomenon for such points, which is the process of the coincidence of different points at a certain value of the parameter. This examination is based on a resurgent representation of the corresponding solutions which also depends on the parameter. In particular, the confluence of the representations in question is considered.