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The concentration of halogens in apatite, biotite and amphibole is investigated for a large variety of mantle-derived plutonic rocks (gabbros, diorites, monzonites, olivine- and pyroxene-bearing monzonitic to granitic rocks, syenites, carbonatites and a phoscorite). In all rocks studied, apatite occurs as an early magmatic phase, whereas biotite and amphibole may occur either as a late magmatic phase or as late-stage, potentially hydrothermal product replacing precursor olivine, pyroxene and Fe–Ti oxides (ilmenite and magnetite). Based on electron microprobe analyses for F and Cl and detailed textural observations, we test existing models of halogen partitioning between apatite and biotite. Bromine concentration data for apatite, biotite and amphibole are used to further refine our understanding of the geochemical similarities and differences between Cl and Br during magmatic and hydrothermal processes. Our data suggests that F and Cl contents in apatite, biotite and amphibole can indeed be useful monitors of the halogen systematics in magmas, but they may also be subject to post-magmatic changes to variable extents. The relatively small radius and compatible F cation seems to be less prone to post-magmatic alteration and is likely to best reflect the original magmatic halogen abundances — especially in apatite. However, the larger and probably more incompatible Cl anion, is more easily re-mobilized as reflected by strong redistribution of Cl in biotite and amphibole which have been clearly overprinted by hydrothermal fluids. In certain cases, the ability of halogens to re-distribute themselves after magmatic equilibrium partitioning (as emphasized by our data) suggests that observed partitioning (especially between apatite and biotite) may also be used as a very sensitive indicator for post-magmatic hydrothermal processes.

Cyclohexene oxide ring opening with N,N-dialkylethane-1,2-diamines and subsequent N,O-acylation give rise to N-(2-acyloxycyclohexyl)-N-(2-aminoethyl)carboxamides. These compounds possess pronounced antiarrhythmic activity and low toxicity.

This paper reports the results of an investigation of metasomatic alterations in basement gneisses within the contact aureole of the Ozernaya Varaka alkaline ultrabasic massif. Based on mineralogical and geochemical data, the metasomatic rocks were classified, variations in major and trace elements were evaluated along a cross-section through the contact zone, the mobility of components during the metasomatic transformation of rocks was estimated, and the gain or loss of components was quantified. The obtained results provided insight into the trends of changes in mineral assemblages, the mechanisms of migration of fluid flows, and, most importantly, the scale of input or removal of major and a number of trace components at different stages of the evolution of the metasomatic system within the contact aureole and border zones. It was shown that a fluid phase was released directly from a magma chamber filled with alkaline ultrabasic melt, which is indicated by the high 3He/4He value (5.9 × 10−6) of the fluid, corresponding to 50% of the mantle component. It was shown that the release of a considerable amount of fluid phase related to the alkaline ultra-basic melt was not accompanied by a significant input of high field strength and rare earth elements. In contrast, the fluids of the subsequent carbonatite stage were enriched in volatile components (F, Cl, P, and S), which resulted in the migration of REE into the fenitized zones and removal of Ta, Zr, and Hf from it. The low 3He/4He value of this fluid suggests that its noble gases were contaminated by a crustal component, and solutions percolated along fracture systems and shatter zones from the root of the magmatic system. During the final postmagmatic stage, alkaline metasomatism was caused mainly by aqueous fluids and was accompanied by the removal of all rare earth elements and most of the high field strength elements (Nb, Ta, Zr, and Hf). A comparison of the fenitized zone of the Ozernaya Varaka complex with those of the Khibiny and Lovozero agpaitic syenite massifs showed that the metasomatic reworking of gneisses in the multiphase alkaline ultrabasic complex occurred in several stages and was accompanied by the input and removal of components, whereas the single-stage fenitization in the agpaitic syenite plutons involved minor amounts of heterogeneous water-fluoride fluids and resulted in extensive migration of rare earth and high-field strength elements in the contact zone.

Aim To evaluate the efficacy and safety of superselective embolization and chemoembolization of the prostatic artery as an independent method of treating prostate cancer and BPH. Materials and methods From 2004 to 2015, 116 patients with BPH (mean age 73.2+/-5.2 years) underwent prostatic artery embolization. Mean prostate volume ranged from 55 to 296 cc3. From 2011 to 2015, 37 patients with prostate cancer (mean age 72.3+/-2.06 years) were treated with X-ray-guided endovascular chemoembolization. All patients had confirmed PCa, of whom 7 had stage T2a and 30 stage T2c disease. PSA ranged from 0.8 to17 ng/ml (mean 13.1+/-3.9). Prostate volume ranged from 61 to 93 cc3 (mean 69.4+/-9.3). The follow-up ranged from 8 to 42 months. Results Prostatic artery embolization in BPH patients resulted in a significant reduction in IPSS symptom score and increase in Qmax. The volume of prostate and nodular mass decreased on average by 53% and 47%, respectively, maximum by 82%. Chemoembolization was effective in 31 (83.7%) patients. An objective response was achieved in reducing the PSA level and prostate volume measured by TRUS, and improved urination. The median PSA at 6 months was - 3.4 +/- 0.02 ng/ml. In all patients, chemoembolization resulted in a marked reduction in the prostate volume. The greatest decrease in the prostate volume was observed at 6 months after treatment. Chemoembolization led to a marked improvement in the quality of urination confirmed by uroflowmetry and IPSS symptom scores. At 12 months, 16 patients with prostate cancer underwent the follow-up biopsy. In 12 cases pathology showed fibrosis and epithelial degeneration without signs of atypia and in 2 cases curative pathomorphosis was observed. Chemoembolization was well tolerated and did not cause any significant complications. Conclusion Embolization techniques for BPH and chemoembolization for localized PCa showed good effectiveness and safety in patients who had medical contraindications to traditional treatments.

This paper reports the results of U-Pb geochronological and Sr-Nd isotopic geochemical investigations (LA-ICP-MS) for perovskite, apatite, titanite, and calcite from the ultrabasic-alkaline rocks of the Paleozoic Kola alkaline province of the Fennoscandian Shield. Based on the obtained data, two main stages were distinguished in the history of Paleozoic intrusions in this province: (1) formation of ultrabasic-alkaline series of the Kovdor, Afrikanda, Turiy Mys, Ozernaya Varaka, Lesnaya Varaka, and other massifs, as well as the ultrabasic-alkaline series of the Khibiny and Lovozero massifs (385–375 Ma) and (2) formation of agpaitic syenites in the Khibiny and Lovozero calderas (375–360 Ma) and related apatite-nepheline deposits (370 Ma). The Sr-Nd isotopic geochemical investigations of perovskite, apatite, and titanite, which are the main hosts for the rare earth elements and Sr in ultrabasic-alkaline rocks, showed that variations in the Sr and Nd isotopic characteristics of these rocks are related to a large extent to crustal contamination during the ascent of their parental melts toward the surface and crystallization in magma chambers. As a result, the Sr and Nd isotopic characteristics of late minerals (apatite and titanite) do not reflect the initial Sr and Nd isotopic ratios of the primary magma. Initial ratios in the primary mantle melts are most closely approximated by the isotopic characteristics of phases crystallizing during early stages (e.g., perovskite).

The Upper Laetolil marker Tuffs 1 to 8 are mineralogically similar rocks, but heterogeneous in terms of their texture, structure, proportion of primary minerals, volume of cement and degree of low-temperature alteration. Originally they were deposited as crystal and/or vitric ash of evolved melilite-nephelinitic composition and not as melilitite-(natro)carbonatite. Occurrence of carbonate-silicate melt inclusions in primary minerals supports R. Hay's conclusion that the ash could have erupted from a carbonatitic volcanic source. Primary minerals (melilite, clinopyroxene , garnet , perovskite , magnetite) in the tuffs are characterised by wide variations in their compositions and two and even more mineral populations are present within each marker tuff. Thus, any correlation between the tuffs from different localities on the basis of mineral composition is very difficult to impossible. Tuff 7, with footprints of Australopithecus afarensis, is a very heterogeneous unit both vertically and laterally that formed during four major eruption events. Trace-element geochemistry and Sr–Nd isotopic data for Tuffs 6, 7 and 8 suggest that compositionally different volcanic sources were involved in their formation. Initial 87Sr/86Sr and 144Nd/143Nd ratios also show that the Sadiman volcano should not be considered as a source for these three marker tuffs at Laetoli. Only Essimingor and Mosonik volcanoes produced rocks that are mineralogically and geochemically similar to the Upper Laetolil marker tuffs, though these volcanoes lie about 100 km from Laetoli.

The mathematical statement of the problem for route optimization of multi-rotor aerial vehicles has been developed. In this formulation, the indicated problem is a Traveling Salesman Problem (TSP) of an asymmetric closed type. As a target functions of optimization the total energy consumption of MRAV motion along the broken line passing through n given points in the order given by the permutation (problem 1) and the total time of flying around the route along a broken line passing through n given points in the order given by the permutation (problem 2) have been proposed. It is shown that when a MRAV DJI Inspire 1 flies around the route points which have different altitudes, the differences between the "intuitive" and the optimal variants can be up to 43%. The more is difference in altitudes of the points to be flied around, the more is the difference between the "intuitive" and the optimal route variants. From practical point of view, the solution to problem 1 can be used in case there is a need to save MRAV power sources for solving some other problems. The solution to problem 1 is needed in case when there is a need for faster flying around the route.On average, the benefit of using optimization for an aerial vehicle of this type is 17-18%.

The results experimental studies of the microwave electromagnetic field effect on the structure and physical and mechanical properties of polymeric fibrous materials are presented. These methods and tools for studying the microwave effect on this object. The possibility for the nonthermal microwave modification of thermoplastic polymers has been proved.

The paper presents the results of a study of the large Paleozoic ore-magmatic system in the northeastern Fennoscandian Shield comprising the Khibiny and Lovozero plutons, the Kurga intrusion, volcanic rocks, and numerous alkaline dike swarms. As follows from the results of deep drilling and 3D geophysical simulation, large bodies of rocks pertaining to the ultramafic alkaline complex occur at the lower level of the ore-magmatic system. Peridotite, pyroxenite, melilitolite, melteigite, and ijolite occupy more than 50 vol % of the volcanic-plutonic complex within the upper 15 km accessible to gravity exploration. The proposed model represents the ore-magmatic system as a conjugate network of mantle magmatic sources localized at different depth levels and periodically supplying the melts belonging to the two autonomous groups: (1) ultramafic alkaline rocks with carbonatites and (2) alkali syenites-peralkaline syenites, which were formed synchronously having a common system of outlet conduits. With allowance for the available isotopic datings and new geochronological evidence, the duration of complex formation beginning from supply of the first batches of melt into calderas and up to postmagmatic events, expressed in formation of late pegmatoids, was no less than 25 Ma.

The Kola Peninsula is characterized by diverse alkaline magmatism, including alkaline ultramafic, carbonatite, “kimberlite” and agpaitic rocks, although many aspects of the ages of emplacement and petrogenesis remain unresolved. In this study, rocks from the Afrikanda complex (pyroxenite, ijolite, melteigite, carbonatite, and perovskite ore) were selected for U–Pb age determination and Sr–Nd isotopic analyses using in situ ion probe and laser ablation techniques. The perovskite U–Pb ages are 377 ± 6 (pyroxenite), 379 ± 5 to 385 ± 5 (calcite-bearing perovskite ore) and 376 ± 5 (ijolite–melteigite) Ma, indicating that the different phases of the complex were contemporaneously emplaced at ~ 380 Ma. These ages are comparable to those obtained previously for Afrikanda rocks, and other alkaline ultramafic, carbonatitic, “kimberlitic” and agpaitic complexes in the area; suggesting that the majority of alkaline magmatism in the Kola Peninsula occurred at ~ 375–380 Ma. Sr–Nd isotopic analyses of perovskite, titanite, apatite, and calcite indicate that the Afrikanda complex was derived from a depleted mantle. However, these data suggest that silicate and carbonatitic magmas are not related by simple crystal fractionation within a closed magmatic system. The silicate magma has an initial 87Sr/86Sr isotopic ratio of ~ 0.7034 to 0.7038 and eNd(t)380 value of ~+2.0 to + 4.9, whereas the carbonatitic magma was more primitive with the above values of ~ 0.7033 to 0.7035 and eNd(t)380 ~ + 5.1 to + 5.8, suggesting that either both magmas were derived from two distinct mantle sources or by contamination of a melts derived from a single source. In combination with other geochronological and geochemical data for other complexes in the area, it is proposed that the Kola alkaline magmatism was controlled by mantle plume activity at ~ 380 Ma.

The new paleomagnetic data on forty dikes and two intrusive plutons of Devonian age located in different parts of the Kola Peninsula, which have not been previously covered by systematic paleomagnetic studies, are reported. We describe the results of the rock magnetic, petrographic, and microprobe investigations of the Devonian dikes and present their isotopic ages (40Ar/39Ar, stepwise heating). Within the studied area, almost all the Devonian dikes, metamorphic Archaean-Proterozoic complexes of the Fennoscandian Shield, and Proterozoic dikes have undergone low-temperature hydrothermal-metasomatic alteration, which resulted in the formation of new magnetic minerals with a secondary (chemical) component of magnetization. The comparison of the paleomagnetic poles indicates the Early Jurassic age of the secondary component. We suggest that regional remagnetization event was caused by endogenic activity genetically related to the formation of the Barents Sea trap province 200–170 Ma ago. On the basis of the obtained data, the preliminary Devonian paleomagnetic pole of the East European Platform is determined.

Rareearth element distribution in the rocks and minerals of the olivinite-clinopyroxenite- melilitolite-melteigite-ijolite-nepheline syenite series was analyzed to study the evolution trends of the alkaline-ultrabasic series of the Kola province. The contents of REE and some other trace elements were determined in olivine, melilite, clinopyroxene, nepheline, apatite, perovskite, titanite, and magnetite. It was established that distribution of most elements in the rocks of the Kovdor, Afrikanda, Vuoriyarvi, and other massifs differ from that in the Khibiny ultrabasic-alkaline series, being controlled by perovskite crystalliza� tion. Primary olivine-melanephelinite melts of the minor ultrabasic-alkaline massifs are characterized by the early crystallization of perovskite, the main REE-Nb-Ta-Th-U depository. Precipitation of perovskite simultaneously with olivine and clinopyroxene results in the depletion of residual magma in rareearth ele� ments and formation of lowREEand HFSE ijolite and nepheline syenite derivatives. In contrast, the for� mation of the Khibiny ultrabasic-alkaline series was complicated by mixing of olivine melanephelinite magma with small batches of phonolitic melt. This led to a change in crystallization order of REEbearing titanates and Tisilicates and accumulation of the most incompatible elements in the late batches of the melt. As a result, the Khibiny ijolites have the highest REE contents, which are accommodated by highREE apa� tite and titanite.

The charging programs for a blast furnace with a nonconical charging system are investigated. On that basis, rational charging conditions are developed and tested. Experimental experience indicates more economical furnace operation, on account of the improved batch distribution over the charge hole and the reduced heat losses through the cooling systems.

Well completion using technology enabling to improve performance and life time is an important objective in the development of PK1 productive reservoir of North Komsomolskoye field. The main challenge of the development of this productive horizon lies in the fact that the reservoir is shallow (1,120 m TVD) and consist of poorly consolidated sandstone, which results in massive production of solids during operation. In addition to that, proximity of GOC and WOC together with high oil viscosity in reservoir conditions results in early gas and water breakthroughs when using standard completion technology. Basic PK1 formation characteristics could be found in Table 1. Remote location of the field and impossibility to use all-year-round road transport of materials, equipment and personnel are additional operating problems which had to be resolved to ensure that the project is delivered successfully and without extra costs. Main questions which the project team had to deal with: What is the long-term solution to limit solids production at target drawdown to a level that would be safe for pumps and surface facilities?How to prevent early water and gas breakthroughs?How to drill a long horizontal section in poorly consolidate rock without any incidents knowing that previously several wells were lost in this zone due to well caving during drilling? To tackle these problems, we chose a completion technology for the open horizontal section using screens equipped with autonomous inflow control devices (AICD) and inflow tracers. To ensure sand control, we injected gravel packing in the annular space between the screens and the open well bore. In addition to that, we built a 1D rock mechanic model to calculate well bore stability. During the project execution we drilled 2 long horizontal sections without any incidents; tested completion technology with gravel packing (well A) and without gravel packing (well B); obtained the planned oil inflows; confirmed that the approaches adopted can be successfully used in the Full Field Development. Given all the particular features of the field and the well design, this operation can be rightly considered one of the most complex onshore operations that have been performed in the Russian Federation.

There are several stages of endogenous activity identified in the geological evolution of the northeast� ern part of Fennoscandia; the longest of them finished 1.8 Ga and then this part of the craton stabilized and had a pattern with the structural features close to the modern ones. The following long amagmatic period of more than 1.3 Ga finished in the Paleozoic by plume� lithospheric processes that formed the Kola alkaline province (0.40–0.36 Ga) and completed the develop� ment of riftogenic structures of the southeast White Sea region [7]. Later geological evidence that could signify the manifestation of endogenic activity in the period from 350 Ma until the present has not been found within northeastern part of the shield. Assessment of geodynamic environments existing at the Phanerozoic stage in the evolution of northeast Fennoscandia and reconstruction of motion trend for the Kola megablock in the Paleozoic are of great importance for determination of what the localization conditions of mantle melts produced the Kola alkaline province were. The paleomagnetic method can be involved in solution of this problem; however, the interval of 400–340 Ma BP is the most discussed in the Phanerozoic segment of the apparent polar wander path (APWP) for the East European Craton because of the nearly total absence of reliable paleomagnetic poles of the Devonian age. In order to obtain new data corresponding the modern criteria of reliability, we carried out reconnais� sance paleomagnetic studies of dolerite and alkaline lamprophyric dyke swarms, whose ages fall within the interval of 390–370 Ma according to the geochrono� logical datings (Rb–Sr, Sm–Nd

The paper reports the construction of mathematical models to study the phenomenon of self-regulation (autostabilization) of temperature in the bioreactor of a continuous type with one or two biological objects. These models have been parametrically identified and their adequacy proved on the basis of experimental data. They have been used to find the boundaries of the existence of this phenomenon and to analyze its basic occurrences. The performed calculation experiments have shown how to use this phenomenon in practical applications.

Data on processes that occurred at contacts of large agpaitic syenite intrusions and basement gneisses obtained by the authors by studying and sampling profiles across the contacts and involve the composition of minerals, analysis of mineral assemblages, isotopic dating of the processes, and analysis of the behavior of major, volatile, and trace elements in rocks near the contact. The contact zones of the massifs were determined to consist of products of contact interaction during the early and late magmatic stages and provide a record of successive stages of a continuous process of gneiss transformations, starting with the filling of the magmatic reservoir with melt and ending with late- and postmagmatic processes related to the development of a system of alkaline veins and pegmatite bodies in the gneisses. Early alkaline metasomatic processes in the Khibina Massif were local, controlled by diffusion, and were induced by the immediate thermal and chemical effect of alkaline melts on the gneisses. In the Lovozero Massif, metasomatism was related predominantly to the development of postmagmatic veins at 359 ± 5 Ma, was controlled by infiltration, and proceeded immediately after the consolidation of the main intrusive series. The metasomatic transformations during the early and late magmatic stages under the effect of agpaitic melts on gneisses predetermined different closure conditions and, correspondingly, different behaviors of the Rb-Sr and Sm-Nd isotopic systems during the contact processes: while the interaction of agpaitic melts with gneisses has modified the (87Sr/86Sr)(T = 370 Ma) ratio via the enrichment of radiogenic Sr in the host Archean rocks, the Sm-Nd isotopic characteristics of the syenites in the inner contact zone and veins preserved their mantle values, which corresponded to the average ones for rocks in the central parts of the intrusion. Experimental data, model simulations, and natural observations testify that Nb, Ta, Zr, Hf, and REE were mobile in the contact interaction zone with agpaitic melts. With regard for data on the fluid regime of the agpaitic melts and the concentrations of volatile components in the contact zones, we believe that the main role in the transfer of REE and HFSE during contact metasomatism could be played by their ligands with F−, Cl−, and SO42−.