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The SPIN experiment is carried out with the aim of studying inclusive production of charged particles with high transverse momenta in hard proton−nucleus and nucleus−nucleus interactions. A single-arm narrow-aperture spectrometer is used in the study. The uniqueness of the experiment is in the high intensity of the proton (1012−1013 protons/s) and ion (of the order of 5 × 109 ions/s) beams ejected from the U-70 accelerator, which makes it possible to measure inclusive cross sections varying by seven orders of magnitude. The SPIN setup is able to detect particles with momenta in a kinematic domain of nucleon−nucleon interactions as well as beyond its limits. The spectrometer equipment and the features of the measurement procedure are described.

Data on the production of positively charged particles emitted at an angle of 40$${}^{\circ}$$ (in the laboratory frame) with transverse momenta of up to 2.7 GeV$$/c$$ in the interaction of 50-GeV$$/c$$ protons with carbon, aluminum, copper, and tungsten nuclear targets are presented. Particular attention is given to studying the production of light nuclear fragments, such as deuterons ($$d$$) and tritons ($$t$$). An analysis of data on $$d$$ and $$t$$ particles gives grounds to state that these fragments arise via a local mechanism of their direct knockout from nuclei. The results were obtained in the SPIN experiment at the Institute for High Energy Physics (IHEP, Protvino).

Mitral annular calcification (MAC) is a chronic degenerative process involving the fibrous part of the mitral complex, characterized by calcium deposition and loss of valve function. MAC prevalence is 8–10%, but despite this, the clinical significance of MAC is underestimated. Currently, there are reports that complete decalcification leads to improved long-term outcomes in patients with severe MAC. An analysis of the immediate outcomes of mitral valve surgery in patients with severely calcified mitral annulus with decalcification was performed. The calcified annulus fibrosus underwent complete decalcification in all cases. Calcium deposits were removed in a single block, in 6 cases it was reconstructed with a xeno-pericardial patch; in 2 cases the annulus fibrosus was sutured. There were 2 cases of in-hospital mortality, caused by acute heart failure on day 8 in 1 patient and pulmonary embolism on day 30 after operation in the second patient. There were no complications associated with coronary artery injury and left ventricular posterior wall rupture. Experience in the treatment of severe mitral valve calcification with extensive annulus fibrosus decalcification and subsequent reconstruction is possible and gives satisfactory results.

Results of an experimental study of the local structure of the mean and fluctuating flow in a near-wall gas jet injected through inclined cylindrical holes along a smooth surface and in the case of injection in a transverse trench are reported. The local structure of the near-wall jet is measured by means of the particle image velocimetry. Injection of the secondary near-wall air jet into the main turbulent flow leads to a significant deformation of the streamwise velocity profile of the gas in both test cases. In the case of injection through the holes in the trench, the streamwise velocity of the gas displays a noticeably smoother profile with no clearly expressed maximum behind the cross section of the transverse trench exit. The streamwise velocity of the gas in the near-wall region has a smaller value than that in the case of injection without the trench. The transverse component of the gas velocity in the case of injection without the trench is greater than the corresponding value in the case of injection through the holes in the transverse trench after the gas leaves the trench.

In view of the successful experience in the generation of pion and kaon secondary beams using a focusing crystal, it has been proposed to build at the U-70 accelerator a new-type channel of secondary particles that does not consume electric power. It has been shown experimentally that an extraction septum magnet can be protected from radiation by applying a multistrip crystal device through current septum shadowing by the crystal that involves the bulk reflection regime for the deflection of particles. The listed applications of crystals are novel in the world practice with accelerators.

Experimental data have been presented on the evaporation rate of suspended droplets of both pure water and water containing ≈1.5 wt % surfactant, sodium dodecyl sulfate. Evaporation occurs in a convective flow of dry air, with its velocity and temperature being varied within ranges of U0 = 1–5 m/s and T0 = 20–80°C, respectively. The density of the mass flux from the surface of the surfactant-containing droplets is 2–3 times lower than that in the case of pure water. For droplets in a dry air flow, the change in their diameter can be described by a set of similarity criteria, and a generalized linear empirical dependence of the evaporation rate on thermodynamic parameters may be constructed for these droplets.

This paper considers the problem of the numerical simulation of the propagation dynamics of a dispersed admixture and heat transfer in a swirling turbulent gas–droplet flow behind a sudden tube expansion. The gas phase is described by a system of three-dimensional Reynolds-Averaged Navier-Stokes equations with taking into account the effect of particles on the transport processes in the carrier phase. The gas-phase turbulence is calculated with the Reynolds stress transport model with allowance for the effect of the dispersed phase. The Euler and Lagrangian descriptions give qualitatively similar results for small droplet sizes of up to d1 ≤ 30 μm; it is only for the largest particles studied in this paper (with an initial diameter of d1 = 100 μm) did the difference in the calculation results exceed 15%.

In the pathogenesis of arterial hypertension (AH), the renin-angiotensin-aldosterone system plays a key role in helping to maintain elevated blood pressure. At the same time, the state of angiotensin-II production (AT II) and the expression level of its receptors on target cells determine the formation of most of the effects underlying the pathogenesis of associated clinical conditions in such patients. Thus, the study of the pathogenesis of AH, namely the study of the role of the AT II axis, the AT II receptor, is an actual scientific and practical task. Aim. Given the important role of type 1 receptors for AT II in the formation of pathological changes in arterial hypertension, the purpose of this study was to study the peculiarities of the effect of their expression on biochemical processes in patients with arterial hypertension. Material and methods. In the course of the clinical study, 60 patients of both sexes with hypertension aged 45 to 55 years old were admitted to the clinic for planned treatment. Depending on the initial level of expression of receptors for AT II (AT1R), determined by the serum concentration of the soluble form of type 1 receptors for AT II, the patients were divided into two subgroups with conditionally low (corresponding to the concentration of the soluble form of the receptor for AT II 0.66 ng/ml) and conditionally high (1.57 ng/ml) expression. The analysis showed that high expression of AT1R is associated with elevated plasma levels of renin by 30.8% (p=0.0005), AT II by 48.1% (p=0.00001), E-selectin by 47.9% (p=0.0001), VCAM-1 by 29.1% (p=0.00001), ICAM-1 by 52.9% (p=0.00001), VE-cadherin by 50.9% (p=0.00001), endothelin-1 by 48.8% (p=0.0005), an ACE inhibitor by 13.6% (p=0.047), and CRP by 74.1% (p=0.00002 ) and endoperoxide by 29.7% (p=0.009). Against this background, there was a decrease in the level of apoA1 by 21.6% (p=0.027), ACE by 20.1% (p=0.1), the level of antioxidants by 22.3% (p=0.00001). The analysis showed that in the group with initially high expression of AT1R, there was an increased blood pressure, the level of which, on average, exceeded the values of patients with low expression of the indicated receptor by 24.5 mm Hg (p=0.011). Against the background of therapy in the group with high expression of AT1R, plasma renin activity decreased by 20.3% (p=0.013), endoperoxide by 8.4% (p=0.038), an ACE inhibitor by 14.6% (p=0.02). At the same time, the level of apoA1 increased by 8.5% (p=0.036), antioxidants by 8.6% (p=0.036), ICAM-1 by 5.3% (p=0.05), VE-cadherin by 2.5% (p=0.07). The level of the remaining factors was not statistically significant. In the subgroup with low expression of the AT II receptor, during treatment, there was a decrease in endoperoxide by 12.8% (p=0.031), an ACE inhibitor by 5.5% (p=0.044) without significant changes in other indicators. Conclusion. In hypertensive patients, higher expression of AT1R is associated with high activation of immune-inflammatory mechanisms, dyslipidemia, an imbalance of the lipid peroxidation system and antioxidant protection, as well as higher renin-angiotensin-aldosterone system activity and increased arterial pressure. On the background of antihypertensive therapy, partial compensation of the identified changes is achieved, including a moderate increase in the level of antioxidants, a decrease in the concentration of endoperoxide, renin activity and an increase in the level of apoA1, while maintaining an increased level of AT II, high expression of receptors to it. These changes indicate the need for further search for effective antihypertensive therapy strategies aimed at limiting the activity of renin-angiotensin-aldosterone system in patients with hypertension.

Escherichia coli is a representative of the natural normal microflora of humans and animals. At the same time, some variants may acquire pathogenic properties that contribute to the occurrence of intestinal and extraintestinal infections. In the pathogenesis of these diseases, the main role is played by exotoxins. Currently, along with the well-known and well-studied toxins of Escherichia coli, there is information about new toxoid structures detected in this pathogen, which play an important role in pathologies in humans and animals. Authors summarized current data on the toxigenic properties of Escherichia coli bacteria and established the role of exotoxins of pathogenic Escherichia coli in the mechanism of disease development. Scientific publications of mainly foreign researchers were used as a material for the review. It was found that cyclodomodulating exotoxins that affect the eukaryotic cell cycle were currently identified in Escherichia coli in addition to thermolabile, thermostable, shigalike, necrotizing toxins and hemolysin. Also Escherichia coli has a number of pore-forming toxins that destroy the epithelial barrier and overcome the protection of the host's immune cells due to the formation of pores in their membranes, and so-called repeated toxins, the prototype of which is а-hemolysin. Thus, it can be seen from the review that Escherichia coli, having a wide range of toxoid structures, can cause pathological changes in the human and animal body. The nature of these changes directly depends on the type of E. coli and the type of exotoxin produced by them. Most toxigenic strains of Escherichia coli have the ability to modulate the expression of proinflammatory cytokines, chemokines and other immune cells, which can be further used in the design of effective vaccines and biological products for the treatment and prevention of enterobacterial infections.

This paper presents the results of a numerical study of the effect of a positive longitudinal pressure gradient in a pipe with a sudden expansion on the turbulent two-phase flow structure and local heat transfer. It is shown that a longitudinal pressure gradient has a significant effect on flow characteristics and heat transfer in separated gas-droplet flow. Increasing the diffuser opening angle leads to a significant increase in the degree of flow turbulence (almost twofold increase compared to gas-droplet flow in a pipe with a sudden expansion at $$\varphi=0^\circ$$ ). It is found that in the flow under study, the length of the recirculation zone is significantly increased in comparison with separation gas-droplet flow at $$\varphi=0^\circ$$ and the point of maximum heat transfer rate is shifted downstream. Furthermore, the coordinate of the point of maximum heat transfer rate does not coincide with the coordinate of the reattachment point of the detached two-phase flow.

The authors have presented results of an experimental investigation into the velocity field in a turbulent boundary layer behind a thin (0.00045 m) three-dimensional plate. The chord of the plate (streamwise length) was equal to 0.55δ (δ is the boundary-layer thickness), and its width, to 1.0δ. The plate was installed at a zero angle of attack at the center of a water channel at a distance of 0.09δ from the surface. Velocity-field measurements have been performed by the Particle Image Velocimetry method at the Reynolds number Reh = 7750 calculated from the channel half-width and the velocity at the center of the channel. It has been shown that the average velocity increased in a logarithmic region of the boundary layer at a distance of its three thicknesses behind the plate. Longitudinal-velocity pulsations decreased in the buffer region of the boundary layer, but grew in the logarithmic region. Vertical pulsations only decreased to a distance of 0.8δ behind the plate, but downstream they were higher than in an unperturbed boundary layer. The high resolution of the velocity field (50·10–6 m) has made it possible to determine shear stresses on the wall from the velocity gradient in a laminar sublayer. Shear stresses on the surface behind the plate decreased in the interval where a growth in the average velocity in the logarithmic region was noted. Maximum reduction in the shear stresses occurred at a distance of 1.8δ and amounted to ~33%. The influence of edge effects was manifested in the less intense reduction on shear stresses in the shorter interval behind the plate.

The results of an experimental study of the influence of longitudinal positive and negative pressure gradients in a rectangular flat channel with a backward-facing step on turbulent heat transfer i...

This paper presents the experimental and numerical results of modeling the local structure of gas-liquid downflow in a vertical pipe. The measurements were carried out using the PIV/PLIF system “Polis-PIV,” developed at the Institute of Thermophysics SB RAS. The numerical model is based on the use of a two-fluid Eulerian approach. The effect of changes in the diameter of air bubbles on the local flow structure and wall friction in a two-phase bubbly flow is studied.

The results of numerical simulation of the flow structure and heat transfer in a vertical polydispersed bubbly flow are presented. The mathematical model is based on the Euler approach taking into account the effect of bubbles on the mean characteristics and turbulence of the carrier phase. The polydispersed distribution of bubbles size in a two-phase flow is modeled by the method of delta approximation considering the process of bubble break-up and coalescence. Carrier phase (fluid) turbulence is predicted using the Reynolds stress transport model. The simulation results showed good agreement with the experimental data presented in the literature. The measured and predicted thermal-hydraulic parameter distribution indicates that in a turbulent bubbly flow, the wall friction increase is greater than heat transfer enhancement.

The flow structure and thermal efficiency of a gas-droplet wall jet, injected through inclined holes into a transverse trench, is analyzed numerically. The predictions are carried out using three-dimensional RANS equations in the following ranges of two-phase flow parameters: initial droplet size d1 = 0–20 µm and their mass fraction ML1 = = 0–0.05. Gas turbulence is simulated using the model of Reynolds stress transport taking into account the two-phase character of the flow. The obtained simulation results are compared using the Eulerian and Lagrangian descriptions. The applicability of both approaches to describing the dynamics and heat transfer of a two-phase wall jet is shown.

The results of a bibliometric analysis of studies on quantum information processing for 2000–2017 are presented. We used Science Citation Index Expanded (SCIE) as a data source. This article reveals countries with significant volumes of research, as well as the main participants in the “quantum race.” The structure of a coauthor network was studied in terms of the analysis of social networks using the Salton index; in the analysis of citation, indicators were used based on the calculation of not only the average number of links to a publication, but also highly cited publications in the top 1 and top 10%. The sources and structure of sponsorship of published results in the field of quantum information processing are identified. The positions of Russia are evaluated on all considered indicators.

The first data on the yield of the lightest nuclear fragments (protons p, deuterons d, and tritons t) with high transverse momenta pT at an angle of 40° in the laboratory reference frame from nuclear targets bombarded by 50-GeV/c protons and 20A-GeV/c carbon nuclei obtained in the SPIN experiment (IHEP, Protvino, Russia) have been reported. It has been shown that the pA and CA data can be described within a common scaling approach, which possibly indicates that the mechanism of formation of high-pT nuclear fragments is common for these reactions.