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Aim. The analyses of radial artery patency during hospitalisation in patients with acute coronary syndrome after percutaneous coronary interventions were performed using three options of radial approaches, i.e. traditional, classical and dorsopalmar distal radial approaches.Methods. Patients (n = 178) with acute coronary syndrome on whom endovascular procedure by the traditional and two options of distal radial approach were performed met the entry criteria. The classical distal radial approach was performed within an anatomic snuffbox in 65 patients (36.5%), and the dorsopalmar type was performed in 29 patients (16.3%); the traditional radial approach was performed in 84 patients (47.2%). On completion of the percutaneous coronary interventions and final radial artery angiography, hemostasis was performed with bandage application for 6 h. From the 5th to the 7th day after intervention, examination, palpation and ultrasound duplex scan were performed in every patient.Results. Examination, palpation and ultrasound duplex scan performed from the 5th to 7th day after intervention revealed 3 cases (1.7%) of forearm radial artery occlusion (high type). All the 3 cases were in the traditional radial approach group. Access side radial artery occlusion (at the anatomical snuffbox and the dorsum of the plant [local type]) with saved blood supplement on the forearm was registered in the classical distal radial approach group in 4 cases (2.3%). There were no cases of access side radial artery occlusion in the dorsopalmar group.Conclusion. The use of the distal radial approach for primary percutaneous coronary intervention in patients with acute coronary syndrome definitely reduces the risk of radial artery occlusion of the forearm, whereas the dorsopalmar distal radial approach can be considered as a basic approach.Received 11 May 2020. Revised 31 May 2020. Accepted 3 June 2020.Funding: The study did not have sponsorship.Conflict of interest: Authors declare no conflict of interest.Author contributionsConception and design: S.P. Semitko, R.V. AkhramovichData collection and analysis: R.V. Akhramovich, I.S. MelnichenkoDrafting the article: R.V. AkhramovichCritical revision of the article: S.P. SemitkoFinal approval of the version to be published: R.V. Akhramovich, S.P. Semitko, A.V. Azarov, I.S. Melnichenko, A.I. Analeev, I.E. Chernyisheva, A.A. Tretyakov, D.G. Ioseliani

The transradial access has deservedly become the 'gold standard' while performing various X-ray endovascular interventions both diagnostic and therapeutic ones. However, along with all its advantages, it is not without disadvantages. These difficulties for the most part are related to peculiarities of the anatomy of upper-limb arteries. It is exactly complex anatomy that is the most common cause of complications and compelled change of the access while using the right radial artery. The purpose of our study was to examine the symmetry of complex anatomy of upper-limb arteries in order to choose an optimal and safe way of conversion of the access in case of forced refusal from the right radial access. For this reason there was developed an open multicentre registry acronymized as COMPAAS (COMPlex Anatomy of Arteries and Symmetry). During the work of this Registry from February to December 2018, correspondents of the study became 35 colleagues from 23 clinics of 11 cities of Russia. The working group analysed a total of 127 patients presenting with 157 variants of complex anatomy of lower limb arteries: high bifurcation of the radial artery (84), complete loop or tortuosity (66), and compartmental calcification of brachial arteries (7). The anatomy of arteries on the opposite upper extremity was studied based on angiographic findings. The most frequent variant (84 cases) of complex anatomy was high bifurcation of the radial artery at the level of the a. brachialis (20.9% of cases), with the origin of the brachial artery at the level of the a. axillaris being revealed half as often (9.9%). The maximum percentage of symmetry was observed in the group of patients presenting with compartmental calcification of upper-limb arteries (85.7%). Complete loop or marked (more than 100°) tortuosity of arteries on both arms was revealed in 54% of cases. Besides, in 25% of cases, tortuosity was combined with the high origin of the radial artery. It is noteworthy that none of the 127 patients appeared to have complex anatomy on the a. ulnaris. When revealing pronounced calcification of arteries of the forearm or a combination of high bifurcation with tortuosity, it seems feasible to decide upon conversion of the access to the femoral one (a. femoralis) or ulnar (a. ulnaris). In isolated high bifurcation on the right, effective conversion to the contralateral (left) radial approach is possible in not less than 75% of cases.Трансрадиальный доступ заслуженно стал золотым стандартом при выполнении различных рентгенэндоваскулярных вмешательств как диагностических, так и лечебных. Однако, наряду со всеми его достоинствами, он не лишен недостатков. Эти трудности в основной своей массе связаны с особенностями анатомии артерий верхних конечностей. Именно сложная анатомия является наиболее частой причиной осложнений и вынужденной смены доступа при использовании правой лучевой артерии. Целью нашего исследования стало изучение симметричности сложной анатомии артерий верхних конечностей для выбора оптимального и безопасного пути конверсии доступа в случае вынужденного отказа от правого радиального доступа. По этой причине был разработан открытый мультицентровой регистр COMPAAS (COMPlex Anatomy of Arteries and Symmetry). В период работы регистра с февраля по декабрь 2018 г. корреспондентами исследования стали 35 коллег из 23 клиник 11 городов России. Рабочей группой проанализированы 127 пациентов со 157 вариантами сложной анатомии артерий верхних конечностей: высокая бифуркация лучевой артерии (84), полная петля или извитость (66) и футлярный кальциноз артерий предплечья (7). Анатомия артерий на контрлатеральной верхней конечности изучена на основании ангиографических данных. Самым частым вариантом (84 случая) сложной анатомии была высокая бифуркация лучевой артерии на уровне a. brachialis (20,9% случаев), отхождение лучевой артерии на уровне a. axillaris выявлено в 2 раза реже (9,9%). Максимальный процент симметричности отмечен в группе пациентов с футлярным кальцинозом артерий верхних конечностей (85,7%). Полная петля или резкая (более 100°) извитость артерий на обеих руках выявлена в 54% случаев. Кроме того, в 25% случаев извитость сочеталась с высоким отхождением лучевой артерии. Примечательно, что ни у одного пациента из 127 не было отмечено проявлений сложной анатомии на a. ulnaris. При выявлении выраженного кальциноза артерий предплечья или сочетания высокой бифуркации с извитостью целесообразно рассмотреть вопрос конверсии доступа на бедренный (a. femoralis) или локтевой (a. ulnaris). При изолированной высокой бифуркации справа эффективная конверсия на контрлатеральный (левый) лучевой доступ возможна не менее чем в 75% случаев.

We present a photoluminescence study of In(As,P) monolithic nanoinclusions into Si (100) substrates. The structures were grown in openings of the silicon substrates using an original approach based on the metal-organic vapor epitaxy method. The obtained arrays of In(As,P) nanoinclusions into the Si (100) surface were investigated by scanning microphotoluminescence spectroscopy. The obtained results show high crystalline quality of In(As,P) inclusions with broad emission peak in the near-infrared range of wavelengths.

We studied experimentally and numerically self-heating of a microdisk laser developed in the AlGaInAs material system and covered with dielectric layers. By experiments, we found that planarization of the microlaser with SU-8 photoresist significantly (almost, 2-fold) decreases the microlaser thermal resistance. Calculations demonstrate that a downward heat flux through the substrate to the heat sink is a dominant way of heat dissipation, and upward convection is much less relevant. Also, the calculations showed that covering microlaser with a TiO2 layer barely affects microdisk temperature but decreases heat localization in the structure.

The data of studies of fish populations in the basin of the Baidaratayakha river, received in 1998, 2002, 2013, 2014 are summarized for the first time. 18 species of fish are noted. Most of them belong to commercial and valuable species. The greatest species diversity is characteristic of the lower reaches of the river. In deep lakes and sections of the river near these lakes the density of fishes is higher. Scantiness of the fish population of river sites is due to the fact that most of the riverbeds in winter freeze. For this reason, there is no common minnow in the rivers. In most of the tundra non-riverine lakes that dominate among the waterbodies of the basin, there are no fish due to their shallow water and freezing. Some lakes of the lower reaches of the Baidaratayakha river are inhabited by fish only in summer (Asian smelt for breeding and whitefish for feeding). In some lakes, residential groupings (whitefish and pike) are formed. The estuary is used for feeding of whitefish from the Yuribey river and migrants from various regions of the Kara Sea (Arctic char, pink salmon, omul). The omul remains for the wintering in the estuary, most of the other whitefish return to the Yuribey river. The number of populations of residential forms of fish in most lakes is low due to low fish productivity and poaching. To preserve the resources of valuable fish species, it is proposed to include into the existing reserve Gornohadatinsky section of the upper and middle course of the Baidaratayakha river, where there are lakes that provide a reserve of grayling, and spawning grounds for the reproduction of arctic char and pink salmon.

In the article, the results of the studies of the present state of freshwater ecosystems and their biotic components in the western part of the Yamal Peninsula are presented. Based on the evaluation of the structure of the communities of phytoplankton, zooplankton, benthos and whitefishes, the range of the problems related to the protection of biological resources at the development of the Kruzenshternskoye gas field is defined. Data on species composition and quantitative indicators of hydrobionts of different types of waterbodies and watercourses in the lower reaches of the Mordyyakha and Naduyyakha rivers basins are the basis for environmental monitoring of water objects at development and exploitation of the Kruzenshternskoye gas field. According to the monitoring program, evaluation of the fish fauna state and their food base on the territory of the Kruzenshternskoye gas condensate field (GCF), is present. The zones of rivers deltas are the most important areas of the salmonid and whitefishes valuable fish species feeding at the territory of Kruzenshternskoye GCF. In the cases where complete demolish of waterbodies and watercourses for construction of facilities for GCF does not occur, changes of quantitative and qualitative characteristics of communities of hydrobionts after cease of works are reversible. River ecosystems are restored within a more short period of time in comparison to lacustrine ones. On the basis of conducted comprehensive studies, the proposals for the protection of fisheries resources and monitoring of aquatic ecosystems are reported. Recommendations for reducing the anthropogenic impact on aquatic ecosystems in the development period are presented. The results of the investigation were used in the designing the environmental protection part of the Kruzenshternskoye deposit project. At present, the disturbances in the territory of Kruzenshternskoye deposit of gas does not impact the aquatic ecosystems

The article presents the results of studies on the impact of long-term development of placer gold deposits on the ecosystem of the small mountain river in Subpolar Urals (basin of the Ob River) where whitefish species spawn. Significant reduction in species diversity and quantitative characteristics of epiliton and invertabrate communities in the regions located directly below the mining sites have been found. It is shown that an increased intake of fine sediment leads to a violation of the conditions of valuable whitefish species spawn incubation of as a result of siltation of spawning grounds.

The results of studies of the current state of freshwater ecosystems and their biotic components in the western part of the Yamal Peninsula are presented in the article. Based on the evaluation of the structure of communities of phytoplankton, zooplankton, benthos, and whitefishes, the range of problems related to the protection of biological resources during the development of the Kruzenshternskoye gas field is defined. The data on species composition and quantitative indicators of hydrobionts of different types of waterbodies and watercourses in the lower reaches of the Mordyyakha and Naduyyakha Rivers basins is the basis for environmental monitoring of water objects during development and exploitation of the Kruzenshternskoye gas field. Estimation of the fish fauna state and their food base in the territory of the Kruzenshternskoye GCF according to the monitoring program is present. The river delta zones are the most important feeding areas of the salmonid and whitefishes valuable fish species in the territory of Kruzenshternskoye GCF. In cases where water bodies and watercourses are not completely demolished for the construction of GCF facilities, changes of quantitative and qualitative characteristics of communities of hydrobionts after the end of operations are reversible. River ecosystems are restored within a shorter period of time in comparison to lacustrine ones. Proposals for the protection of fisheries resources and monitoring of aquatic ecosystems on the basis of comprehensive studies are reported. Recommendations on reducing the anthropogenic impact on aquatic ecosystems in the development period are present. The results of the investigation were used in the development of the environmental protection part of the Kruzenshternskoye deposit project. Anthropogenic disturbances present now on the gas deposit territory of Kruzenshternskoye does not influence the aquatic ecosystems. The article have been prepared within the Project of the Presidium of the Russian Academy of Sciences № 12-P-47-2013 and "The Arctic" Project of the Presidium of the Ural Branch of the Russian Academy of Sciences № 12-4-3-012.

Quartz glasses containing ultradisperse particles (with a mean radius of 5 ± 3 nm) of semiconductor compounds CuxS and CuInS2 were synthesized using the sol-gel technology. The line and differential absorption spectra of such glasses were investigated. In the range 600–700 nm, the samples demonstrate absorption bands that are assigned to the lowest-lying energy transition in quantum-size particles. Excitation by laser pulses with a wavelength of 540 nm causes the effect of induced absorption in the range of 500–950 nm. The induced absorption in the samples containing CuxS nanoparticles undergoes relaxation which has a characteristic time of ∼500 psec, and in the samples with CuInS2 nanoparticles it has a two-exponential form with τ1 ≈ 30 psec and τ2>1 nsec.

Silica glasses with ultrafine CuxS and CuInS2 particles (average radius of 5±3 nm) were fabricated by means of a sol–gel technique. Linear and differential absorption spectra were studied. The glasses reveal absorption peaks in the 600–700 nm range associated with the first excitonic resonance in the quantum confined particles. Laser excitation by 540 nm pulses leads to the induced absorption effect in the 480–980 nm spectral range. The relaxation of the induced absorption has a time constant equal to about 500 ps for CuS-doped glasses and a biexponential type (with τ1≈30 ps and τ2>1 ns) for CuInS2-doped ones.

The influence of annealing in hydrogen on spectral-luminescent properties of Ce-containing silica gel-glasses vitrified in air at 1200°C has been investigated. It is established that such annealing at temperatures from 1000°C to 1200°C for highly activated glasses is accompanied by the formation of two main types of new luminescent optical centers of triply charged cerium ions. These centers differ from the centers obtained at lower annealing temperature by positions of the 5d-sublevels and by higher optical transition probabilities. The formation of these new centers is due to the structural reorganization of Ce-containing clusters. Such reorganization is explained by the relaxation of the local environment of reduced (Ce 4+ ) − ions incorporated into the clusters to the equilibrium state.

Eu-and Ce-Eu-containing quartz glasses obtained by a direct sol-gel-glass transition are investigated. It is discovered that the conversion of a xerogel into a glass leads to lowering of the symmetry of the Eu3+ optical centers from hexagonal to orthorhombic and a many-fold increase in the efficiency of the excitation of their luminescence through the charge-transfer band. In the co-activated glasses, the distortion of these centers is enhanced, and compound Ce4+-Eu3+ centers appear, in which the Eu(III) oxo complexes are characterized by cubic symmetry and by sensitization of the luminescence of the Eu3+ ions by photoreduced (Ce4+)− ions. Crystal-field theory shows that the coordination number of the cation in such oxo complexes is equal to 8. It is established that similar structural formations exist in annealed xerogels, but they are manifested spectroscopically only upon low-temperature shortening of the interatomic distances, as a result of which the sensitization indicated becomes possible.

A novel method of fabrication of silica-based sol-gel films and glasses containing small semiconductor particles was developed. A series of films and glasses with nanoparticles of copper chalcogenides (CuS, Cu2Se, CuInS2) and metal particles (Cu) were fabricated through the chemical transformation of precursors incorporated into a sol-gel derived matrix. The properties of the nanoparticles studied by means of XRD, XPS, TEM and optical spectroscopy are provided both by size effects and the chemical nature of surface states and can be controlled at different steps of chemical treatment.

The preparation, composition and optical properties of silica films and glasses produced by the sol–gel technique with incorporated copper compounds have been studied. Heat treatment of the samples in hydrogen or hydrogen sulfide results in a chemical transformation of copper oxide particles into small copper particles or copper sulfide particles, respectively. Optical absorption of samples with the different copper compounds have been measured in UV, visible and near IR regions and features in the observed absorption spectra are briefly discussed.

The spectroscopic behavior of Sm3+ ions is investigated in monoactivated and coactivated (with cerium) glasses obtained by the direct sol-gel-glass transition. It is shown that the majority of the Sm3+ ions form optical centers of the same type, whose luminescence spectral characteristics depend weakly on the concentration of the activator and the technique used to introduce it. Complex centers, including Sm3+ and Ce4+ ions bound by bridge oxygen, are also formed in the coactivated glass during the pore nucleation stage. The Sm3+ ions in these centers are characterized on the average by higher local symmetry, the efficient enhancement of luminescence by photoreduced (Ce4+)− ions, and its extinction by Ce-containing clusters.

A spectral-luminescent study of Ce-containing silica gel-glasses doped at the sol stage and by impregnating porous xerogels with activator chloride salt solutions has been performed. The influence of the degree of doping and redox conditions of vitrification on the activator charge state and the content of hydroxyl ions and chlorine in the glass is considered. The preservation of the glass phase composition and the non-linear increase in the visible absorption intensity with increasing activator concentration from 5 × 1017 to 3.0 × 1020 ions/cm3 are noted. It is concluded that there are two main types of optical centre. It is assumed that they represent Ce(III) oxygen complexes whose nearest surrounding includes quadruply charged (the first type) and triply charged (the second type) ions of cerium. Evidence has been obtained in favor of the superexchange excitation transfer to the central ion of Ce(III) oxygen complexes from photoreduced to the triply charged state of the same ion name of Ce(IV) oxygen complexes.

Silver nanoparticles and clusters were produced within the conventional sol–gel process with tetraethylorthosilicate hydrolysis. The appearance of the reduced silver species was recorded by optical absorption spectroscopy as the plasmon resonances in the range of λ>370 nm, and the other absorption features (λ

In Co- and Cu-containing silica gel-glasses vitrified in air, the activators existed as oxide complexes of Co(II), Co(III), Cu(I) and Cu(II). Annealing of these glasses in hydrogen at temperature ≤800°C leads to reduction of cobalt to the doubly charged state and reduction of copper to the metallic state. An increase in the annealing temperature by 100–300°C results in a deterioration of the optical quality of the glass because of light scattering.

A significant interest in preparation and investigation of optical properties of Er-doped silica glasses has been recently noticed. Such glasses are important in telecommunication systems as materials for construction of signal amplifiers [1]. The glasses may be obtained by the soI-gel technology which allows us to produce high optical quality silica glasses at low temperatures [2]. The most essential limitation of the sol-gel glass is a high concentration of OH— groups which are the principal technological factor decreasing the luminescence quantum yield of Er-doped silica glasses. A significant decrease in the hydroxyl ion concentration is possible by thermal treatment of xerogels in a freon atmosphere [1]. In the present work we report the inIluence of such treatment on optical characteristics of Er-doped silica glasses obtained via the sol-gel method.

Optical materials prepared by the sol-gel process are of current technological interest. Sol-gel silica glasses doped with rareearth (RE3+) ions are an important class of optical materials with applications including solid-state lasers, optical waveguides, fiber amplifiers and devices for optical communications. In this paper, we describe the preparation of rareearth- doped silica-gel glasses and discuss the infrared properties of silica structure as a function of heat treatment. The samples were prepared from tetraethoxysilane (TEOS), water, ethanol, fumed silica and soluble in a water or ethanol the salts ofthe RE3+(Er3+,Nd3+,Sm3+,Pr3+,Eu3+) elements.

The high concentrated silica glasses doped with Ce and Sm ions were prepared by the sol-gel technique. The possibility of preparation of the Ce-doped glasses with a low absorption coefficient in the optical range above 350 nm and the luminescence quantum yield >= 90 percent is reported. Such glasses seem to be promising as filters for laser heads. The relatively high light scattering for Sm-doped glasses has been also observed.

In this paper we report the optical properties of Er-doped silica fibers. The fibers were produced from glasses obtained by sol-gel method. Luminescence spectra of Er3+ ion were measured in monolithic glass samples after excitation by a xenon lamp, as well as in the fiber after excitation by an IR 980 nm diode laser. It was found that under the IR excitation, a green emission at 540 nm was observed due to the up-conversion effect. This effect is associated with the aggregation of Er ions and constitutes an important factor reducing the efficiency of 1.55 micrometers emission.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The paper presents the optical properties of glasses and optical fibers from quartz glass, obtained by the sol-gel method. A new technique of sol-gel glass preparation is described. Rods were formed from the glass thus produced from which PCS-type fibers were next drawn. Using the same sol-gel technology, the erbium-doped quartz glasses were obtained. The transmission and luminescence characteristics were measured for the glasses as well as for fibers drawn from them.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.