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INTRODUCTION: The development of organ dysfunctions and multiple organ failure (MOF) in patients with severe ischemic stroke (IS) is a factor in aggravating the clinical course and outcome. OBJECTIVE: To study the prognostic aspects of the clinical course and outcomes of severe IS with the development of MOF. MATERIALS AND METHODS: The study included 110 patients with severe IS (National Institutes of Health Stroke Scale ≥ 16 points). To assess the severity of MOF on days 1 and 5 of hospitalization, standard scales SAPS II, SOFA were used. The predictor significance of the indicators was determined by a comparative regression analysis using the least squares method. RESULTS: In patients with a fatal outcome compared to survivors, a higher severity of MOF on the SAPS II was observed both on the first (31 (25; 39) and 24 (21; 29) respectively, p

—A multi-chord beam diagnostic system for an open multiple-mirror trap GOL-NB is described. The system is based on a 10 keV ribbon beam of fast neutral hydrogen atoms generated by a wide-aperture ion injector with an arc plasma source. The plasma linear density profile is calculated from the attenuation of the beam after passing through the plasma. This paper discusses the design of the diagnostics and its capabilities, and also presents the measured profiles of the linear plasma density in the experiment on filling the trap with the starting plasma. The modernized version of diagnostics and the expected increase in its resolution are described. The prospects of using the Charge eXchange Recombination Spectroscopy (CXRS) method on the existing element base are evaluated.

The system is described for the formation of the low-temperature starting plasma flow in the GOL-NB trap. The starting plasma is a target for capturing heating neutral beams. The plasma flow is formed in the arc plasma gun installed in a relatively weak magnetic field. Next, it is compressed in the increasing magnetic field and then transported to a distance of approximately 4 m. The design of the plasma gun is described. Optimization of the operating regimes and scenarios of the system for creating the starting plasma made it possible to reduce the gas load onto the vacuum system of the facility, which resulted in reducing the losses associated with the presence of gas dragged along together with the plasma. The plasma flow at the outlet from the high magnetic field section is increased approximately four times, as compared to the results of the first plasma campaign. It is discussed how the limiters and other intrachamber electrodes affect the plasma flow formation. The achieved plasma flow parameters will be sufficient to start the experiments on plasma heating with the help of neutral beams at the GOL-NB multi-mirror trap in its full-design configuration.

The SMOLA open magnetic trap was created at the Budker Institute of Nuclear Physics of the Siberian Branch of the Russian Academy of Sciences (BINP SB RAS) for studying the physics of suppression of plasma longitudinal losses from the system in which rotating plasma is confined in a magnetic field with helicoidal symmetry. The possibility of controlling the plasma rotation velocity is crucial in this concept. Methods of spectroscopic and magnetic diagnostics that allowed obtaining parameters of plasma rotation in the experiments are described. The angular plasma rotation velocity was found to be (0.5–1) × 106 s–1 in different regimes of system operation. The dependences of angular plasma rotation velocity on various parameters of the experiment are discussed.

Objective: to identify the prognostic aspects of the ischemic stroke (IS) focus characteristics according to the data of computed tomography of the brain.Patients and methods. We examined 80 patients with hemispheric IS up to 1-day old (50 patients for constructing mathematical models of disease outcomes and 30 patients for subsequent testing of the obtained models) aged 30-84 years.Results and discussion. The analysis of the association between mortality probability and brain midline shift size shown that a brain midline shift of 4.5-5 mm did not increase mortality probability much, which indicates the synergistic stability of this system. System destabilization began after an increase of the brain midline shift for more than 5-5.5 mm. After a mild change in the initial indicator (6-8 mm), mortality probability increased from 25% to 90% and higher. When the brain midline shift was more than 8.5 mm, the system, from the synergistic viewpoint, became stable again but with an unfavorable prognosis. This analysis helps to identify the critical decision-making point when analyzing the IS focus neuroimaging characteristics. Thus, the point for the focus volume is 145 cm3, and for the brain midline shift - 5.0 mm.Conclusion. The results of our study about the prognostic value of the IS focus characteristics according to CT data may have additional value for decision-making in the management of patients with a poor prognosis.

This article presents the results of theoretical and experimental studies on the electrodynamic system of an accelerator module, which is a part of the linear induction accelerator (LIA) (BINP and RFNC-VNIITF). In the course of this research, 3-D models of the LIA accelerator module with the geometry close to the real one have been created. These models allowed us to calculate the main parameters of the electromagnetic eigenmodes for these modules. To verify the calculation results, an experimental stand permitting to register the spectral properties of the dipole modes has been built. The main results of the work are the electromagnetic field distributions of the modes in the accelerator module obtained in modeling, as well as the mode spectra calculated and registered in “cold” experiments (without beam). Based on the obtained data, the main features of the oscillation’s spectral composition and their $Q$ -factors have been established in the frequency range $f\approx 300{(\!{-}\!)}1100$ MHz, and the effective methods for suppressing these oscillations have been proposed. The development of such methods is absolutely necessary in order to reduce the increment of the beam breakup (BBU) instability, which is the main obstacle in the increase of the beam current in LIA.

A diagnostic has been developed to study the focusing dynamics of a high-power electron beam on a target. The diagnostic uses a pinhole camera to observe bremsstrahlung from the converter target. A data acquisition system yields images of the beam focal spot with a frame duration of 20 ns and an almost unlimited recording duration. The focal spot dynamics of a linear induction accelerator with an energy of 1.5 MeV, a current of 1.2 kA and a pulse duration of 350 ns were studied. The focal spot was found to be disrupted within the first 100 ns of the pulse. Defocusing has a complex 3-D character. The feasibility of additional cleaning of the target using an accelerator pre-pulse was shown. Stable beam focusing for up to 200 ns was demonstrated.

The current integration state of ITER Equatorial Port #11 (EP#11) is described. This port is the first plasma port and thus the integration phase is close to the final stage. The new modular design of neutron shielding is implemented in the Diagnostic shielding modules’ (DSM) construction to achieve the maximum shielding efficiency within the weight restrictions and keeping fully operable the tenant diagnostics systems. The same approach was applied to Interspace structure frame design to allow the safe hand-on maintenance near the highly activated components. The current iteration of the engineering calculations, including the neutron transport and shutdown dose rate (SDDR), thermohydraulics, electromagnetics, seismic, and structure integrity calculations, showed that the current design of EP#11 satisfy all ITER requirements. The special metalworking, welding, and various other technologies are tested during the process of preparation for the manufacturing of ITER EP#11. Production technologies of the full-size DSM mock-up and various elements of its infrastructure were tested. The multizoned clean area assembly hall for the final assembly is close to getting completed and the testing of vacuum items has to be sent to ITER.

Project of submillimeter free electron laser (FEL) is developed at BINP in collaboration with IAP [1] . The FEL scheme is based on a high current electron beam (E e = 5−20 MeV, I b = 1−2 kA, τ= 160−200 ns) generated at the new linear induction accelerator (LIA) [2] , [3] . According to our theoretical analysis, such beam allows us to generate coherent pulses of submm-radiation in the frequency range 0.3-1 THz. The radiation power in such scheme can reach a sub-megawatt level and the energy content up to ~100 J.

The results of a study of the chemical composition, vacuum and thermal properties of boron carbide ceramics, which is planned to be used in ITER diagnostic ports, are presented. The measured boron carbide content in sintered and hot pressed ceramics is 99,0÷99,7%, they do not contain unauthorized impurities, which in accordance to ITER requirements. The outgassing rate of sintered and hot pressed boron carbide produced by Virial Ltd meets the requirements of the ITER Vacuum Handbook. Sintered ceramic is cheaper than hot pressed, and it is produced in large volumes, which it would be preferable for use in ITER ports, but with its massive use may create a significant gas load on the vacuum system that requires accurate analysis and outgassing tests on all candidated ceramics.

Influence of backstreaming ions from the target on spot size of focused 2 MeV electron beam was considered. The 2D version of the particle-in-cell code KARAT was used to study the formation of the ions stream and dynamics of the electron beam. It was shown that light species emitted from the target can disrupt the beam. The emission of low-ionized states of tantalum cannot disrupt the beam during about 30 ns or longer. A few non-invasive techniques of mitigation of the beam disruption were considered. Final magnetic lens with fast variation of magnetic field of several hundred Ampere-turns per nanosecond is capable to stabilize initial spot size of the compressed beam at the target.

While it is commonly accepted that the activation energy of the thermally activated polaron hopping transport in disordered organic semiconductors can be decoupled into a disorder and a polaron contribution, their relative weight is still controversial. This feature is quantified in terms of the so-called $C$ factor in the expression for the effective polaron mobility: ${\ensuremath{\mu}}_{e}\ensuremath{\propto}\mathrm{exp}[\ensuremath{-}{E}_{a}/{k}_{B}T\ensuremath{-}C{(\ensuremath{\sigma}/{k}_{B}T)}^{2}]$, where ${E}_{a}$ and $\ensuremath{\sigma}$ are the polaron activation energy and the energy width of a Gaussian density of states (DOS), respectively. A key issue is whether the universal scaling relation (implying a constant $C$ factor) regarding the polaron formation energy is really obeyed, as recently claimed in the literature [Seki and Wojcik, J. Chem. Phys. 145, 034106 (2016)]. In the present work, we reinvestigate this issue on the basis of the Marcus transition rate model using extensive kinetic Monte Carlo simulations as a benchmark tool. We compare the polaron-transport simulation data with results of analytical calculations by the effective medium approximation and multiple trapping and release approaches. The key result of this study is that the $C$ factor for Marcus polaron hopping depends on first the degree of carrier localization, i.e., the coupling between the sites, further whether quasiequilibrium has indeed been reached, and finally the $\ensuremath{\sigma}/{E}_{a}$ ratio. This implies that there is no universal scaling with respect to the relative contribution of polaron and disorder effect. Finally, we demonstrate that virtually the same values of the disorder parameter $\ensuremath{\sigma}$ are determined from available experimental data using the $C$ factors obtained here irrespective of whether the data are interpreted in terms of Marcus or Miller-Abrahams rates. This implies that molecular reorganization contributes only weakly to charge transport, and it justifies the use of the zero-order Miller-Abrahams rate model for evaluating the DOS width from temperature-dependent charge transport measurements regardless of whether or not polaron effects are accounted for.

The paper presents experimental results from the SMOLA device that is the first facility with a helical mirror section of the magnetic field. This device is built in the Budker Institute of Nuclear Physics for the verification of the helical mirror confinement idea that is the recently introduced technique of the active control of axial losses from a confinement zone. Theory predicts that with rotating plasma, a helical mirror will provide suppression of the axial plasma flow and, simultaneously, density pinching to the axis. Experiments demonstrated that plasma density at the exit from the transport section is suppressed with activation of the helical field, the effect is significant and highly reproducible. The most pronounced effect is observed on the plasma periphery, where the mirror ratio is the highest. The integral suppression ratio reaches 2–2.5 in the discussed experiments. Experimental results are compared with simplified theoretical estimates. The integral suppression ratio matches the simple theoretical estimates even if the transversal diffusion is neglected.

Clinical and radiological features of tuberculosis and sarcoidosis are quite overlapping, and therefore, a diagnostic dilemma often persists. There are no commonly accepted criteria for the diagnosis of sarcoidosis due to the lack of data on the etiology of the disease. The exclusion of tuberculosis in every patient with suspected sarcoidosis is a mandatory stage of diagnosis, especially in countries with a high burden of tuberculosis. A prospective study was conducted with two groups of patients: group I (n = 50)-patients with pulmonary sarcoidosis established according to standard criteria; group II (n = 28)-patients with pulmonary tuberculosis with bacterial excretion. The control group (n = 24) was presented by healthy subjects. The examination complex included x-ray, bacteriological, immunological (Mantoux test with 2 TE, TB.SPOT test), and histological methods. All patients and healthy subjects were assessed for immune complexes with the use of the dynamic light scattering (DLS) method and adding of "healthy lung tissue extract" antigens and specific tuberculosis antigens ESAT-6 and SFP-10 in vitro. Significant differences were found in determining specific immune complexes in patients with pulmonary sarcoidosis and pulmonary tuberculosis. Registration of specific immune complex formation with "healthy lung tissue extract" in 100% cases may indicate the autoimmune nature of sarcoidosis. The absence of the immune complex formation in response to ESAT-6/SFP-10 antigens can be used for the differential diagnosis of two diseases. The diagnostic significance of the DLS method was 100% for sarcoidosis and 92.2% for tuberculosis. The data obtained in the study allows not only understanding the etiology of sarcoidosis, but also obtaining new criteria for the differential diagnosis of tuberculosis and pulmonary sarcoidosis.

A system of four-electrode Langmuir probes developed for the GOL-NB multiple-mirror trap is discussed. The system is used for studies of a low-temperature start plasma (1019–1020 m-3, 5 eV) that fills the device during the initial phase of the experiment. The probe allows simultaneous measurements of plasma density, electron temperature and radial electric field. The accuracy of the probe measurements is also discussed.

Novel concept of the longitudinal plasma flow suppression by active plasma pumping in helicoidal magnetic field in mirror traps was proposed recently. Concept exploration device SMOLA is now being constructed to prove the possibility of the suppression and determine basic scalings of ist effectiveness. Technical solutions of the SMOLA device are described in the article. Vacuum system, magnetic system, plasma source and the source of the radial electric field are discussed. Estimations of the biasing required for optimal confinement are given. Physical program fort he first experiments is also proposed.

At present, along with relational databases, the NoSQL databases have become widely used. They have high performance and reliability, because the data are stored in form of records , which are repeatedly replicated. However, absence of an explicit mechanism for conducting transactions and locks of records in these databases leads to a sharp increase in the number of versions of records in the database, while they are updated by several users. In this case, the user workload and time of reconciliation of these versions are growing up, the system performance decreases, and the probability of version loss increases. The number of types of records stored in the database is large, and the number of versions of records cannot be measured at the stage of system operation. Therefore, the actual task is to estimate the number of versions of the record and the time of their reconciliation at the peak load on the system at the stage of its design. This gives a possibility to make a right decision in time. In this case, adequate mathematical models are an indispensable tool for analysis. The article discusses the process of processing (reconciliation) of the record versions. A simulation model has been developed for reconciling the versions of the record, which is updated in parallel by several users. The model allows estimating the time of agreement between the versions of the record and the number of versions simultaneously stored in the database. Based on the results of simulation, the system designer can give recommendations on the maximum possible number of users (or applications) simultaneously working with one document (a database record). This is important if restrictions are placed on the time of document reconciliation. The process of preparation and carrying out of full-scale experiments in the cloud for analysis of model adequacy is described. The results of full-scale experiments show that the developed simulation model of the process of keeping the versions of the record is adequate. The average relative uncertainty in estimating the characteristics of the random number of versions of the record by the model is: for the mean value – 7,5% and the right confidence limit (RCI) – 3,0%. The average relative uncertainty of the estimation by the mean value of the update processing time is 0.22%, RCI – 5,6%.

Experimental research on behavior of rolled tungsten plates under intense transient heat loads generated by a powerful (a total power of up to 7 MW) long-pulse (0.1–0.3 ms) electron beam with full irradiation area of 2 cm2 was carried out. Imaging of the sample by the fast CCD cameras in the NIR range and with illumination by the 532 nm continuous-wave laser was applied for in-situ surface diagnostics during exposure. In these experiments tungsten plates were exposed to heat loads 0.5–1 MJ/m2 with a heat flux factor (Fhf) close to and above the melting threshold of tungsten at initial room temperature. Crack formation and crack propagation under the surface layer were observed during multiple exposures. Overheated areas with excessive temperature over surrounding surface of about 500 K were found on severely damaged samples more than 5 ms after beam ending. The application of laser illumination enables to detect areas of intense tungsten melting near crack edges and crack intersections.

A new test facility for experimental simulation of transient heat load expected in the ITER divertor during unmitigated events is developed. Application of a long-pulse (0.1–0.3 ms) wide-aperture (up to 2 cm 2 ) electron beam as a heating device provides powerful energy loads at a tungsten target with F HF > 250 MJ m −2 s −0.5 . Dynamics of tungsten particles in the ablation plume is investigated with a novel for PSI experiments small-angle laser light scattering technique. The threshold of intense droplet generation and dynamics of particles sizes are estimated.

Experiments on the detection of γ rays generated in the 13C(p, γ)14N reaction at the Novosibirsk vacuum-insulated tandem accelerator were carried out. Owing to the updated detection system, it was possible to measure the energy spread of beam protons and develop a method for long-term stabilization of the slow drift of the beam energy. The measured energy spread was 1.20 ± 0.15 keV, which was only 0.07% of the total beam energy. This makes the tandem accelerator developed by the vacuum-insulated Budker Institute of Nuclear Physics an attractive tool for solving various research and applied problems.

A new control system for capacitive energy storage with a rated energy content as high as 16 MJ is described. Capacitive energy storage has been used since 1987 to supply power for the pulsed magnetic system of the GOL-3 multiple-mirror trap. It has an operating voltage of 6 kV and consists of 6000 IK-6-150 capacitors that are located in six remote rooms together with the necessary infrastructure. The system for control and data acquisition was built using Arduino microcontroller boards operating as a distributed network of remote servers. The client part of the control system uses a personal computer with a standard configuration; communication with remote servers is effected by the TCP/IP protocol. The control system was put into regular operation at devices of the GOL-3 facility in the early 2016.

Results of spectral and magnetic diagnostics of plasma differential rotation in the GOL-3 multiplemirror trap are presented. It is shown that the maximum frequency of plasma rotation about the longitudinal axis reaches 0.5 MHz during the injection of a relativistic electron beam into the plasma. The data of two diagnostics agree if there is a region with a higher rotation frequency near the boundary of the electron beam. Plasma differential rotation can be an additional factor stabilizing interchange modes in the GOL-3 facility.

A new method for SQL query implementation in a parallel execution environment Apache Spark in a package mode was developed on the basis of Bloom Filter Cascade Application (BFCA). It includes representation of the original query in a form of a few subqueries and intermediate tables, where the Bloom filters are created and applied. Then the representation is transformed into Scala code. Theoretical justification of the developed method is provided. The theoretical estimation of the network data transmission volume reduction (shuffle) is shown on an example. The efficiency of the method is demonstrated on the example of Q3 (three tables join) and Q17 (correlated subquery) queries from the TPC-H test. The developed BFCA method is more than 2 times faster and more than 10 times better on shuffle volume (as compared to Spark SQL) on Q3 at a Scale Factor SF=500. The BFCA is 8 times faster on Q17 than Hive (Spark SQL cannot implement Q17).

The results of long-term outgassing test of large quantities of ceramics, which is planned to be used in ITER diagnostic ports, are presented. The outgassing rate of boron carbide ceramics produced by Virial Ltd meets the requirements of the ITER Vacuum Handbook. Massive use of ceramics in ITER may create a significant gas load on the vacuum system that requires accurate analysis. Calculations of gas emission of Equatorial Port #11 were performed and it was demonstrated that a significant amount of ceramics can be used for neutron protection. Experiments on activation of ceramics and stainless steels by fast neutrons were carried out, which showed a rapid reduction of residual radioactivity and absence of hazardous impurities.

A two-color infrared interferometer has been developed for the investigation of high-density weakly ionized tantalum plasma in x-ray complexes based on linear induction accelerators (1.6 kA electron beam current, 4.6 MeV energy, and 100 ns pulse duration). Simultaneous probing at two different wavelengths makes it possible to independently measure the density of neutral and electron components. The interferometer uses wavelength values of 1.064 µm (Nd:YAG laser) and 10.6 µm (CO2 laser). To attenuate the effect of sample beam refraction in inhomogeneous plasma, the interferometer used a refraction suppression scheme composed of spherical mirrors focusing the object beam into the region occupied by the plasma. In addition, the power of the sample beam transmitted through the plasma was controlled in order to analyze whether there was a distortion of the interference pattern because of strong sample beam refraction and absorption in the plasma cloud. To calibrate the initial phase shift of the probe radiation, a movable mirror mounted on a piezoelectric element and oscillating according to a harmonic law with amplitude greater than the laser wavelengths was used. In initial experiments, the parameters of target plasma registered by this interferometer are as follows: the linear density of neutrals reached 1.5 · 1017 cm−2, and the degree of ionization was of the order of 10−2. The target plasma expansion velocity is determined as ∼6 km/s.

Damage of divertor tungsten tiles as a result of transient plasma processes is one of the key problems of the ITER tokamak. Even if the temperature of the divertor tiles is maintained below the melting threshold, their thermal deformation, accumulation of residual stresses and cracking will occur. Cracking reduces the resistance of the metal to subsequent loads, therefore, the study of this process is important. In materials science, non-destructive methods for measuring mechanical stresses are very limited. In this work, a new method is proposed that allows non-contact investigation of stresses in polycrystalline tungsten plates by their bending. A corresponding diagnostic system and theoretical model are implemented. A number of experiments were carried out using this diagnostic system at the BETA facility at the Budker Institute to study the dynamics of tungsten plates bending with different thickness, subjected to pulsed heating of different intensities. The experimental results showed the qualitatively expected process of the plate bending, as well as good agreement with the theoretical model. This proved that the method described in the work is promising for use in order to study the residual stresses in a pulse-heated metal sample.