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The article presents a construction of a coherent pulsed microwave bridge with an output power up to 10 Wt with a time resolution of 10–8 seconds at a pulse repetition rate of 1 kHz designed for electron spin echo spectrometers. The bridge is built on a homodyne scheme based on IMPATT diodes, which are used for modulation and amplification of microwave power coming from the reference Gunn diode oscillator. The advantages of the bridge are optimal power and minimum pulse width, simple operation, low cost.

Aims. Based on the available observational data from the literature, we analysed the dynamics of the NGC 6240 galaxy central supermassive black hole (SMBH) system. Methods. For the dynamical modelling of this triple SBMH system, we used the massively parallel and GPU accelerated φ-GPU direct summation N-body code. Following a long-timescale modelling of the triple system, we carried out a very detailed time output analysis of the von Zeipel–Lidov–Kozai (ZLK) oscillations for the black holes. Results. According to our Newtonian simulation results, for all models and randomisations, the bound system from S1+S2 components formed at ≈3.6 Myr. The formation of the bound hierarchical triple system S+N occurred at ≈18 Myr. Over the course of these Newtonian simulations of the evolution of the triple SMBH system and the surrounding environment in NGC 6240, ZLK oscillations were detected (in most cases) for the binary components. The inclination angle between the orbital angular momentum of binary components aptly coincides with the theoretical calculations of the ZLK mechanism. Conclusions. In our set of randomised 15 Newtonian N-body dynamical galaxy models in 13 systems, we were able to detect a ZLK mechanism. In contrast, our extra few-body post-Newtonian runs (for one randomisation case) show it is only for the large inner binary initial eccentricity (in our case ≳0.9) that we are able to observe the possibility of the inner binary merging, due to the post-Newtonian energy radiation effects. For the lower eccentricity cases, the test runs show no sign of possible merging or any ZLK oscillations in the system. [ABSTRACT FROM AUTHOR]

Copyright of Recent Contributions to Physics is the property of Al-Farabi Kazakh National University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We have developed the dynamical model of a clumpy torus in an active galactic nucleus (AGN) and compared to recent The Atacama Large Millimeter Array (ALMA) observations. We present N -body simulations of a torus in the field of a supermassive black hole (SMBH), made of up to N  = 105 gravitationally interacting clouds. As initial conditions, we choose random distributions of the orbital elements of the clouds with a cut-off in the inclination to mimic the presence of wind cones produced at the early AGN stage. When the torus reaches an equilibrium, it has a doughnut shape. We discuss the presence of box orbits. We have then constructed the velocity and velocity dispersion maps using the resulting distributions of the clouds at equilibrium. The effects of torus inclination and cloud sizes are duly analysed. We discuss the obscuration effects of the clouds using a ray tracing simulation matching the model maps to ALMA resolution. By comparing the model with the observational maps of NGC 1068, we find that the SMBH mass is |$M_\text{smbh}=5\times 10^6 \, \mathrm{M}_\odot$| for the range of the torus inclination angles 45°–60°. We also construct the velocity dispersion maps for NGC 1326 and NGC 1672. They show that the peaks in the ALMA dispersion maps are related to the emission of the torus throat. Finally, we obtain the temperature distribution maps with parameters that correspond to our model velocity maps for NGC 1068. They show stratification in temperature distribution with the shape of the high-temperature region as in the VLTI/MIDI map. [ABSTRACT FROM AUTHOR]

The alkylation of 1H-tetrazole, 5-methyl-1H-tetrazole, and 5-phenyl-1H-tetrazole with primary, secondary, and tertiary alcohols, including benzylic and allylic ones, have been studied in 1,2-dichloroethane in the presence of boron trifluoride–diethyl ether complex. Neither primary nor secondary saturated alcohols alkylated tetrazoles in the given system. Tertiary alcohols such tert-butyl alcohol and adamantan-1-ol reacted with unsubstituted and 5-substituted tetrazoles to give 70–85% of the corresponding 2-alkyl-5-R-tetrazoles with high regioselectivity. The alkylation of 1H-tetrazole with benzyl alcohol afforded 55% of 2-benzyl-2H-tetrazole as the only product. The alkylation of 1H-tetrazole with various allylic alcohols led to the formation of mixtures of 2-alkyl-2H-tetrazoles with isomeric alkyl substituents. [ABSTRACT FROM AUTHOR]

Copyright of Scientific Bulletin of National Mining University is the property of National Mining University, State Higher Educational Institution and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A regional GNSS network consisting of 202 permanent GNSS stations established to study the recent crustal strain deformation in the Ukrainian territory. The GNSS observations (from December 7, 1997 to January 28, 2017) collected and processed using Bernese GNSS Software ver. 5.2 in accordance with the recommendations of the Central Bureau of the EUREF Permanent GNSS Network. Based on the above results the velocity vectors were estimated using Bernese GNSS Software ver. 5.2 for the future calculation of deformation. In particular, ellipses of distortion, rotation, maximum shear strain, and deformation area are obtained. Due to the differences in rate of the horizontal extension and rotation the area is divided in two main blocks. The first block shows compression that prevails in the North-East direction. Stretch in both directions is prevailing on second block. The obtained results can indicate the presence of some force which could effect on the study area. [ABSTRACT FROM AUTHOR]

Crustal strain for the northern region of Ukraine is determined at the GNSS Data Analysis Center of the Main Astronomical Observatory of the National Academy of Sciences of Ukraine based on the triangular method with GNSS stations as vertices. Crustal strain was calculated using the GPS Triangle Strain Calculator software developed by UNAVCO. [ABSTRACT FROM AUTHOR]

For the first time, a homogeneous coordinate solution in the IGS05 reference frame and the values of the zenith tropospheric refraction for the GPS weeks 935-1399 (from December 12, 1997 to November 4, 2006) were obtained at the GNSS Data Center Analysis of the Main Astronomical Observatory NAS of Ukraine. The obtained solution is devoid of effects, brought by changes in the methods of processing models, a priori data and software (absolute phase center model combinations of antenna-dome instead of relative models, model of ocean loading FES2004 instead of GOT00.2_PP, the elevations cut-off angle 3° instead of 10°, etc. were used). To estimate the quality of the solution, a comparison with the international combined solutions using the Helmert transformation was carried out. The RMS of direct station coordinate differences and correlation coefficients between the solutions estimated by the Main Astronomical Observatory, European GNSS Permanent Network and International GNSS Service are presented. The obtained results allow making the conclusion that the solution obtained at the GNSS Data Center Analysis of the Main Astronomical Observatory shows a good quality and agrees well with other solutions. [ABSTRACT FROM AUTHOR]

Based on a set of rigorously computed velocities of GNSS (Global Navigation Satellite Systems) sites of the CEGRN (Central European GNSS Research Network) we identify a number of areas with large scale tectonic structures and interpolate the velocities to the profiles by least squares collocation. The resulting velocity field provides an invaluable data set for the investigation of present day crustal deformation at the continental scale. We present six velocity profiles covering structural features of Central Eastern Europe and at the same time well populated by GNSS sites, to minimize interpolation errors. One N-S profile samples the stretching of the crust in the Balkan-Aegean region, three E-W profiles sample the part of Central Europe north of the Black Sea, one SW-NE profile crosses the Trans European Suture Zone. A sixth profile outlines the shear deformation associated with the eastward extrusion of the Eastern Alps towards the Pannonian Basin. Analytical modelling of the first and last profiles, for which there is a significant deformation, provides quantitative constraints on the relation between back arc retreat and extensional deformation in the continental crust (Aegean-Balkan profile), and model parameters such as the locking depth of faults accommodating the lateral extrusion of the Eastern Alps. For the four remaining profiles, across the TESZ and the Central Europe through the Carpathians, we report a westward velocity East of the TESZ and Carpathians. The velocities appear to drop West of these structures, suggesting that in a conventional 'European fixed' reference frame the East European Craton is generating a small compressional strain in a nearly E-W direction. We show by analytical modelling in an elastic half space that this compression can be accommodated by slip between 8 and 25 mm/yr along fault planes at crustal depths and aligned to the Carpathian orogeny. [ABSTRACT FROM AUTHOR]

Background: Hypertrophic cardiomyopathy (HCM) is the most common genetic cardiomyopathy. Extended septalmyectomy (ESM) is one of the priority methods of treatment of drug-refractory obstructive HCM. In recent years,hospital mortality during surgical correction of obstructive HCM in expert centers does not exceed 1-2 %. However,typical threatening complications of septal myectomy, such as iatrogenic ventricular septal defect (VSD) and rupture of the anterior or posterior walls of the left ventricle (LV), remain a topical issue in surgery of HCM., Objective: to show the role of preoperative CT-planning to predict and reduce possible technical problems associated with ESM, including iatrogenic VSD., Methods and Materials: This study includes 217 symptomatic patients with obstructive HCM, who from April 2016to October 2019 as one of the steps of preoperative planning underwent cardiac CT prior to ESM. Cardiac CT was performed to delineate the left ventricular myocardium, assess the distribution of hypertrophy and the presence ofcrypts. Special attention was also paid to the anatomy of the mitral valve (MV) and subvalvular apparatus. Coronaryartery patency was assessed by CAD-RADS, a standardized method for reporting the results of coronary CT angiography to determine tactics for further management of the patient., Results and Discussion: In the study group, the average age of patients was (49 ± 15) years, 48 % - men. All patientshad a symptomatic, drug-refractory obstructive form of HCM. The mean maximum wall thickness of the interventricular septum (IVS) was (20 ± 5) mm (range 16-33). The average LV mass was (118 ± 23) g/m2. 195 patients (89.9 %)had systolic anterior motion ( SAM) of the MV. MV and subvalvular apparatus anomalies were detected in 62 patients(28.6 %). A zone of scarring and regression of IVS after alcohol septal ablation (ASA) was detected in 7 patients(0.3 %) with residual LV outflow gradient. Coronary arteries atherosclerosis was detected in 32 patients (14.7 %)., Conclusions: Preoperative CT-planning of septal myectomy allows to obtain information on morphology of the LV,IVS, MV and subvalvular apparatus, and gives the surgeon the advantage to form a more accurate plan for the location and volume of septal resection, and avoid complications when correcting obstructive HCM. No iatrogenic VSDwas detected in any of the patient in the study group., (M. O. Tregubova, К. В. Rudenko, V. V. Lazoryshynets, S. V. Fedkiv, O. M. Trembovetskaya, P. A. Danchenko, Yu. I. Vitkovsky, M. S. Ishchenko, A. Yu. Gavrylyshyn, V. V. Parfentyeva, Yu. Yu. Stukov.)

The Central European GNSS Research Network (CEGRN) collects GNSS data since 1994 from contributors which today include 42 Institutions in 33 Countries. CEGRN returns a dataset of coordinates and velocities computed according to international standards and the most recent processing procedures and recommendations. We provide a dataset of 1229 positions and velocities resulting from 3 or more repetitions of coordinate measurements of each site over 4 or more years. The velocity data result from a combination of eight multiyear, partially overlapping networks, using 234 stations of class A of the European Permanent Network (EPN) for alignment to the 'European Fixed' ETRF2000 Reference Frame. The rms (root mean square) of the 8 individual contributions to the combined solution, after a 7 - parameter Helmert transformation, is less than 5 mm in the observation period 1996-2017. This combined CEGRN network maintains the origin coincident with that of the ETRF2000 reference frame to within 1.8 mm rms for the entire period of analysis. The mean positions and velocities of common EPN Class A and CEGRN stations differ by 0.0 ± 1.1, 0.5 ± 1.0 and 0.1 ± 2.7 mm for the coordinates and 0.06 ± 0.13, -0.07 ± 0.12, 0.38 ± 0.28 mm/yr for the velocities respectively for the North, East and Up components at epoch 2010.0., (© 2019 The Authors.)

Diagnostic criteria of sarcoidosis were offered in the 60-ies of XX century, however today the problem of sarcoidosis is difficult for understanding the different specialists and early detection. The development of laboratory diagnostic of viral infections and introduction of polymerase chain reaction (PCR) has greatly improved the level of diagnosis of herpes infections, reveal the previously unknown etiology of many diseases: sarcoidosis (granulomatosis), migraine, multiple sclerosis, cystic prenatal brain damage, convulsions, Hodgkin's disease and others. Sarcoidosis is the set of clinical symptoms (fatigue, shortness of breath, coughing, heaviness in the chest), laboratory, radiological and histopathological data that allow the doctor to diagnose, predict prognosis and treatment policy. Most often, sarcoidosis affects the lungs and thoracic lymph nodes. In the last period for 2011-2013 in 2930 immunologically tested patients the sarcoidosis was confirmed in 146. Primarily these patients were exposed to different diagnosis--COPD, pneumonia, tuberculosis, lung cancer. Among patients with sarcoidosis on the first place in frequency of detection were EBV and HHV-6. We were the first in 2000, described the Epstein-Barr virus as the causative factor of sarcoidosis, and has been hypothesized the immunopathology of sarcoidosis and principles of individual immunotherapy with a resolution of the granulomatous process in 92 % of cases. Subsequently, this association has been and illustrates the relationship to other viruses (HHV-6, HHV-8) demonstrated by other authors.

Of the 40 patients, stenoses of major brain arteries were identified in 34, occlusions in 6, affection of two arteries in eleven patients, that of three arteries in 3 patients. The following disturbances in central hemodynamics were detected: arterial pressure getting higher, this referring also to the peripheral vascular resistance, hematocrit value, with the bloodflow in the arm-ear portion slowing down, hemodynamics being predominantly of hyperkinetic type. Treatment with cavinton, cavinton plus corglucone resulted in improvement of bloodflow in the affected major brain arteries at the expense of a compensating redistribution of bloodflow from intact collectors to the stenosed arteries basin. Changes in central hemodynamics were manifested by increase in the number of cases presenting with eukinetic-type circulation at the expense of decrease in those of hyperkinetic type. Under hypokinetic type hemodynamics, it is advisable that cavinton be prescribed in combination with cardiac glycosides.

As many as 34 patients having stage II-III atherosclerotic dyscirculatory encephalopathy with coexisting ischemic heart disease in the presence of stenosing and occlusive lesions of major brain arteries were evaluated for effects pentoxiphyllin and corglycon on the clinical course of this medical condition as well as systemic and cerebral haemodynamics. In this series, 82.7 percent of patients derived benefit from a single intravenous infusion of pentoxiphyllin and corglycon and course treatment with these drug preparation that was evidenced by an improvement in the parameters of systemic and cerebral hemodynamics and regression of neurologic symptomatology. The results of the studies made permit recommending pentoxiphyllin in combination with corglycon for treatment of those DE patients with eukinetic and hypokinetic types systemic haemodynamics, whereas pentoxiphyllin alone--for those with hyperkinetic type of haemodynamics, taking into consideration its cardiodepressive effects.

Overall thirty-five patients with ischemic insult against the background of occlusive lesions of major arteries of the head were evaluated for effects of cardil on systemic and cerebral hemodynamics and rheologic properties of blood. It has been shown that cardil increases significantly cerebral bloodflow predominantly on the side of the stenosis, does not cause intracerebral "stealing" in the acute phase of insult, improves bloodflow to the brain and collateral blood supply in the residual phase due to selectivity of its influence on cerebral vessels, lowers arterial pressure, decreases frequency of contractions, as well as cardial and stroke indices, and volume of circulating blood. The drug suppresses aggregatory properties of thrombocytes and erythrocytes during different stages of ischemic insult, and makes blood viscosity somewhat less.

Vasoactive preparations (cavinton, corinfar, phinoptin, pentoxyphylline and sermion) were studied for their effect on systemic and cerebral hemodynamics in 232 patients with cerebrovascular insufficiency in the presence of atherosclerotic lesion of the precerebral arteries, and for that on rheologic properties of blood in 91 of them. It has been established that the highest effect from the use of calcium antagonists and sermion with respect of the blood flow linear velocity (BFLV) increase occurs predominantly in stenotic precerebral arteries; the normalization of the platelet-erythrocyte homeostasis is also considerably influenced by these. Calcium antagonists and sermion are capable of lowering arterial pressure, diminishing the volume of circulating blood and cardiac index thereby making for more economic heart performance. Cavinton has only minor effects on systemic hemodynamics, slightly increases BFLV reduces the extent of the erythrocyte aggregation only. Pentoxyphylline has a positive effect on normalization of platelet and erythrocyte homeostasis, reduces blood viscosity and does not influence the parameters of systemic hemodynamics, only slightly increases the linear velocity of the bloodflow in the precerebral arteries. Recommendations on the use of the preparations studied are presented.

Studied was an effect of pentoxyfilline on systemic and cerebral haemodynamics in 33 patients with discirculatory encephalopathy in the presence of atherosclerotic lesion of the precerebral arteries, with the aid of dye-dilution methods using Evans blue (T-1824) and ultrasonic dopplerography. Pentoxyfilline was found to be associated with significant reduction of the circulating blood volume at the expense of its globular fraction, diminution of the cardiac and stroke work indices; the drug has only minor effects on the peripheral vascular resistance and linear velocity of bloodflow in the precerebral arteries; it makes for an increased number of cases of eukinetic type of blood circulation and causes regression of subjective neurologic symptomatology. On account of its antihypertensive and cardiodepressive effect the drug is contraindicated in patients with low AP and hypokinetic type of systemic haemodynamics. If intracerebral steal syndrome is detected, the institution of the pentoxyfilline therapy cannot be recommended.

The Evans blue dilution method and ultrasound dopplerography were used to study the effect of nicergolin on the systemic and cerebral hemodynamics in 31 patients with dyscirculatory encephalopathy against the background of atherosclerotic lesions of the major head arteries. It was established that nicergolin reduces the arterial pressure, diminishes the minute blood volume, cardiac and stroke indices, increases the specific peripheral vascular resistance, the linear blood flow velocity prevailingly in the stenosed major head arteries, results in a regression of the subjective and objective neurological symptomatology. Considering the cardiodepressive effect of nicergolin, this agent is indicated in patients with the hyperkinetic type of the systemic hemodynamics.

Evans blue dilution and ultrasound dopplerography was used to examine 170 atherosclerosis patients with initial manifestations of insufficient cerebral blood supply (77 patients) and transient disorders of the cerebral blood circulation (93 patients) with occlusive and stenotic involvements of the major brain arteries. The authors revealed characteristic aspects of responses of the systemic-hemodynamic mechanisms in initial manifestations of insufficiency of the cerebral blood supply and transient disorders of the cerebral blood circulation with stenosis and occlusions of the major brain arteries and without involvement of the brain vessels. Treatment aspects are discussed.

Transient circulatory disorders of the brain arising in response to stenosis and occlusion of the major head arteries in 111 patients were treated with cardiotonic and vasoactive drugs (corglycon, strophanthin, sulfocamphocain, euphylline++, cavinton, finoptin). The treatment was controlled by monitoring systemic and cerebral hemodynamic parameters. An appreciable clinical response was achieved in more patients (by 16.3%) than it was usually the case in thus untreated patients.

Patients (n = 118) with initial manifestations of brain blood supply failure induced by stenoses and occlusions of the main vessels of the head were treated by cardio- and vasoactive drugs (corglycon, strophanthin, sulfocamphocaine, euphylline, cavinton, verapamil) under control of the systemic (by Evans blue dilution according to Stewart-Hamilton) and cerebral (by rheoencephalography and ultrasound dopplerography) hemodynamics. As a result of such treatment policy, the number of cases with a complete reverse development of the symptomatology was 16.8% greater than in analogous situations where no therapy with the method proposed was carried out.

Blood Evans Blue dilution and ultrasound Doppler cardiography were used to examine systemic and cerebral hemodynamic changes after a single intravenous administration of finoptin (5 mg) and its course treatment (a daily dose of 120-240 mg) in 30 patients with initial signs of cerebrovascular insufficiency and 30 patients with transient cerebrovascular disorders in the presence of atherosclerotic stenoses of the cephalic great arteries. Finoptin was found to increase the linear velocity of blood flow mainly in stenotic arteries, without causing intracerebral steal. The agent also exerted a clear-cut cardiodepressive action which was levelled off by its vasodilating effect by the end of its course therapy.

The effect of vasoactive agents, nootropic drugs and cerebrolysin on blood viscosity was studied in 128 patients with atherosclerotic disordered circulatory encephalopathy. Vasoactive and nootropic agents excluding cerebrolysin reduced blood viscosity, spontaneous aggregation of erythrocytes and thrombocytes. The most pronounced effect in reducing blood viscosity and aggregation properties of erythrocytes produced by sermion, pentoxyphyllin and pyriditol while the spontaneous aggregation of thrombocytes was reduced by calcium antagonists (corinfar, phynoptin) and pentoxyphyllin. Cerebrolysin produced a marked effect on erythrocytes, elevation of blood viscosity. Hence, its use in patients with ischemic blood circulation disorders requires cautious approach.

The effect of cavinton on the systemic (by the method of diluting Evans blue according to Stewart-Hamilton) and cerebral (by the method of rheoencephalography) hemodynamics was examined in 38 patients with chronic insufficiency of the cerebral circulation (CICC) in the presence of either atherosclerosis alone (n = 22) and its combination with arterial hypertension (n = 16). Cavinton decreased the peripheral vascular resistance and the tone of the small and median vessels of the brain, increased the cardiac output and improved the rheological properties of the blood (it lowered the globular volume, viscosity and hematocrit). The best results were attained with the parenteral administration of the drug. Indications for and contraindications to cavinton in patients with CICC are discussed.