The results of investigations of solar-blind image converter tubes (ICTs), sensitive in the vacuum-ultraviolet (VUV) spectral range are presented. Sensitive-conversion layers of photocathodes based ...on boron-doped polycrystalline diamond films were grown up on sapphire substrates for the first time. Electron flow multipliers (EFMs) were fabricated in the form of diamond grid. Solar-blind VUV ICTs without the EFM are characterized by spectral sensitivity range of 180…250 nm, estimate of the threshold sensitivity value ~10-9 W/Hz0.5 and current sensitivity ~12 - 15 mA/W. Solar-blind VUV ICTs comprising the electron flow multipliers are characterized by extended spectral sensitivity range of 180…270 nm, improved estimate of the threshold sensitivity value 10-11… 5 × 10-12 W/Hz 0.5 and current sensitivity 50 mA/W.
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•Solar-blind diamond photocathode is the base of ultraviolet image receiver.•Diamond photocathodes and electron flow multipliers doesn't afraid of light-striking.•Unique properties of diamond are the reason of solar-blind image receiver efficiency.•Base technology for UV image receiver is diamond heteroepitaxy on sapphire or quartz.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•The double helix vortex structure in a tangential chamber was obtained by means of numerical simulation.•Three regimes were simulated according to different swirl numbers.•Several recirculation ...zones were formed in the tangential chamber near its axis.•The frequency of the pressure pulsation was approximately twice the rotational frequency of the double helix structure.•The vorticity redistributes between branches of the double helix structure during its rotation and evolution.
The paper investigates the flow structure in a tangential vortex chamber based on numerical simulation of unsteady turbulent flow by the LES method. The swirl flow in a cylindrical chamber was organized using 12 nozzles, supplying the flow tangentially. Three regimes were considered with different design swirl number S = 5.78, 8.67, and 17.34, which was varied by closing one or two nozzle rows. The unsteady computation shows the formation of a rotating double helix vortex structure in the regimes with S equal to 8.67 and 17.34, which is also verified by experimental observations. Several recirculation zones were formed in the tangential chamber near its axis, as well as along the wall at the lower part, and on the axis near the top lid. A dominant frequency was observed in the pressure pulsation spectrum, which increased with increasing swirl parameter, and for the S = 8.67 regime, it was approximately twice the rotational frequency of the double helix structure. In the course of rotation of the double helix structure, the vorticity redistributed between its branches from an approximately symmetric pattern and up to approaching a single-vortex structure at certain points in time.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Objective and design
The existing biological models of diffuse alveolar damage (DAD) in mice have many shortcomings. To offset these shortcomings, we have proposed a simple, nonsurgical, and ...reproducible method of unilateral total damage of the left lung in ICR mice. This model is based on the intrabronchial administration of a mixture of bacterial lipopolysaccharide (LPS) from the cell wall of S. enterica and α-galactosylceramide (inducing substances) to the left lung.
Methods
Using computer tomography of the lungs with endobronchial administration of contrast material, we have been able to perform an operative intravital verification of the targeted delivery of the inducer. The model presented is characterized by more serious and homogeneous damage of the affected lung compared to the existing models of focal pneumonia; at the same time, our model is characterized by longer animal survival since the right lung remains intact.
Results
The model is also characterized by diffuse alveolar damage of the left lung, animal survival of 100%, abrupt increases in plasma levels of TNFa, INFg, and IL-6, and significant myocardial overload in the right heart. It can be used to assess the efficacy of innovative drugs for the treatment of DAD and ARDS as the clinical manifestations that are developed in patients infected with SARS-CoV-2. Morphological patterns of lungs in the noninfectious (“sterile”) model of DAD induced by LPS simultaneously with α-galactosylceramide (presented here) and in the infectious model of DAD induced by SARS-CoV-2 have been compared.
Conclusion
The DAD model we have proposed can be widely used for studying the efficacy of candidate molecules for the treatment of infectious respiratory diseases, such as viral pneumonias of different etiology, including SARS-CoV-2.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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The work is devoted to a comparative analysis of the quantitative content of extractives and water-soluble polysaccharides isolated from the fruit bodies of mushrooms
Grifola frondosa
depending on ...the extraction methods. As objects of study used strain of fungi
G. frondosa
2639, isolated from commercial mycelium. It was established that the yield of fungi in polypropylene bags (volume up to 4500 cm
3
) was 36.37%, differing little from the yield of fruit bodies in glass containers (volume 800–1000 cm
3
). Using the hydrolysis of extraction products it was found that the methods of extracting the fruit bodies of
G. frondosa
with water lead to the extraction of polysaccharides of different composition. It was established that when using extraction methods in the Soxhlet apparatus, boiling and maceration (25.0 ± 1.0°C), the yield of extractive substances from the fruit bodies of
G. frondosa
was within the literature data interval and was 6.04, 5.81 and 3.45%, respectively. It was shown that the highest content of water-soluble polysaccharides in the fruit bodies of
G. frondosa
was found using the extraction method in the Soxhlet apparatus and was 14.92%, differing from boiling and maceration methods (25.0 ± 1.0°C) by 1.15 and 1.33 times. By HPLC it was found that when maceration extraction was used (25.0 ± 1.0°C) and boiling, the monomeric composition of the polysaccharides of the fruit bodies of
G. frondosa
is mainly glucose, mannose, fucose and rhamnose in a ratio of 1.0 : 0.9 : 0.4 : 1.3, respectively. During extraction in the Soxhlet apparatus, their ratio was 1.0 : 1.2 : 0.5 : 1.9.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Experimental flow-pattern diagram (left); solid lines correspond to a constant swirl parameter, visualization of the flow structure.
The moment of the vortex core reconnection, visualization by the ...pressure isosurface, side view.
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•Reconnection of precessing vortex rope was observed under a model swirler in a narrow range of the flow regimes.•Numerical investigation of the precessing vortex core reconnection was performed by means of large eddy simulation using sliding mesh to model the runner rotation.•Vortex core reconnection occurs at flow regimes range between small swirl number and the region of stable precession of the vortex core.•During the vortex core reconnection two helical vortex turns encounter each other, interact and form a separated vortex ring.•After the vortex ring separates, a disturbance propagates up the vortex rope.
The paper investigates the unstable behavior of a precessing vortex core in a diffuser behind a rotating swirler. The studies were carried out by experimental methods using a hydrodynamic stand, and by numerical simulation of turbulent flow in the stand in the various flow swirl modes. Both experimental and calculation studies show nonperiodic reconnection of the vortex core and the formation of vortex rings. This instability is observed within a narrow range of the swirl parameter between a weakly swirled flow without vortex breakdown and a strongly swirled flow with forming a stable precessing vortex core. The vortex core reconnection leads to forming a wave disturbance propagating along the vortex rope.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The main task of targeted therapy is the selective destruction of cancer cells without affecting normal ones. For these purposes, small molecules and antibodies are used that target specific ...receptors and proteins or block signaling pathways in tumor cells. The natural phytoestrogens daidzein (Dz) and genistein (Gn) possess binding capacity to estrogen receptors (ER). Methionine γ-lyase (MGL) is promising in two strategies of antitumor therapy: for the elimination of l-methionine, which is necessary for the proliferation of tumor cells, and for the production of cytotoxic dialkyl thiosulfinates in situ. For delivery of MGL-loaded nanocapsules (nanoreactors) to the surface of cancer cells a technique for Dz or Gn incorporation into the shell of polyionic vesicles (PICsomes) was developed. The nanoreactors were characterized by dynamic light scattering and transmission electron microscopy. The enzyme retained its catalytic efficiency inside the decorated PICsomes. The binding of Dz/Gn-nanoreactors to the surface of ER + MCF7 breast adenocarcinoma cells was demonstrated. For the first time an influence of enzyme-loaded PICsomes and their individual components on embryos development was evaluated. The high rate of blastocysts formation (>80%) was observed for all tested components and nanoreactors themselves. A strong inhibitory effect on the early embryonic development of MGL-loaded PICsomes in the presence of S-alkyl-l-cysteine sulfoxide substrates was showed. This proves that the substrates can freely penetrate through the polymer shell of the polyionic vesicle and are cleaved by MGL to form cytotoxic thiosulfinates. The data obtained for phytoestrogens decorated PICsomes may be applied in enzyme therapy of malignant tumors.
•Polyionic vesicles were modified with natural phytoestrogenes.•MGL encapsulated into decorated vesicles retained catalytic activity.•Polyionic vesicles loaded with MGL did not reveal embryotoxicity.•Decorated nanoreactors are bound to ER + MCF7 adenocarcinoma cells.•Dz/Gn-MGL-PICsomes are perspective to target cancer cells.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Structural biology is solving an ever-increasing number of snapshots of ion channel conformational ensembles. Deciphering ion channel mechanisms, however, requires understanding the ensemble dynamics ...beyond the static structures. Here, we present a molecular modeling-based approach characterizing the ion channel structural intermediates, or their "dynamic molecular portraits", by assessing water and ion conductivity along with the detailed evaluation of pore hydrophobicity and residue packing. We illustrate the power of this approach by analyzing structures of few vanilloid-subfamily transient receptor potential (TRPV) channels. Based on the pore architecture, there are three major states that are common for TRPVs, which we call α-closed, π-closed, and π-open. We show that the pore hydrophobicity and residue packing for the open state is most favorable for the pore conductance. On the contrary, the α-closed state is the most hydrophobic and always non-conducting. Our approach can also be used for structural and functional classification of ion channels.
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•The magmatic rocks are represented by syenites and lamprophyres.•The age of syenites is 131.4 ± 1.5 (2.9) Ma.•The lamprophyres were formed at 134.9 ± 1.6, 132.3 ± 1.5 and ...117.7 ± 3.4 Ma.•The ore mineralization is presented by the telluride-gold type.
Late Mesozoic Upper Amga alkaline rocks are located in the Amga tectonic mélange zone within the Aldan-Stanovoy shield, Russia. The main phases of the Upper Amga complex consist of alkaline syenite intrusions as well as the lamprophyre dikes and sills. The mineralogical features indicate that the lamprophyre may belong to minette. Recent geological works revealed the linear and area-specific geochemical gold anomalies in association with late Mesozoic alkaline magmatism in the Upper Amga gold district. The age of the syenite intrusions is 131.4 ± 1.5 (2.9) Ma, and the lamprophyre sills and dikes were formed at 134.9 ± 1.6, 132.3 ± 1.5 and 117.7 ± 3.4 Ma. The mineralization is represented by the REE-Ti-Th, polymetallic (sulfide) and telluride-gold types in the quartz-calcite-chlorite alteration of the main magmatic phases of the alkaline rocks. The fluid inclusions study shows that the sulfides were formed from hydrothermal fluids of CO2-N2-NaCl-H2O composition at temperatures ranging from 390 to 340 °C, with 44–22.7 wt% NaCl-eq, whereas the epithermal telluride-gold mineralization originated from low-temperature CO2 ± N2-NaCl-H2O fluids, with the homogenization temperature of 230–210 °C and a of 9.2–3.3 wt% NaCl-eq.
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High-energy particle accelerators have been crucial in providing a deeper understanding of fundamental particles and the forces that govern their interactions. To increase the energy of the particles ...or to reduce the size of the accelerator, new acceleration schemes need to be developed. Plasma wakefield acceleration
, in which the electrons in a plasma are excited, leading to strong electric fields (so called 'wakefields'), is one such promising acceleration technique. Experiments have shown that an intense laser pulse
or electron bunch
traversing a plasma can drive electric fields of tens of gigavolts per metre and above-well beyond those achieved in conventional radio-frequency accelerators (about 0.1 gigavolt per metre). However, the low stored energy of laser pulses and electron bunches means that multiple acceleration stages are needed to reach very high particle energies
. The use of proton bunches is compelling because they have the potential to drive wakefields and to accelerate electrons to high energy in a single acceleration stage
. Long, thin proton bunches can be used because they undergo a process called self-modulation
, a particle-plasma interaction that splits the bunch longitudinally into a series of high-density microbunches, which then act resonantly to create large wakefields. The Advanced Wakefield (AWAKE) experiment at CERN
uses high-intensity proton bunches-in which each proton has an energy of 400 gigaelectronvolts, resulting in a total bunch energy of 19 kilojoules-to drive a wakefield in a ten-metre-long plasma. Electron bunches are then injected into this wakefield. Here we present measurements of electrons accelerated up to two gigaelectronvolts at the AWAKE experiment, in a demonstration of proton-driven plasma wakefield acceleration. Measurements were conducted under various plasma conditions and the acceleration was found to be consistent and reliable. The potential for this scheme to produce very high-energy electron bunches in a single accelerating stage
means that our results are an important step towards the development of future high-energy particle accelerators
.
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KISLJ, NUK, SBMB, UL, UM, UPUK
The paper deals with the experimental study of nanofluids boiling on cylindrical heater. The studied nanofluids were prepared on the basis of distilled water and nanoparticles of silicon, aluminum ...and iron oxides as well as diamond. The volume concentration of nanoparticles varied from 0.05 to 1%. The nanoparticles diameter ranged from 10 to 100 nm, the diameter of the heater was varied from 0.1 to 0.3 mm. It is revealed that the use of nanofluids provides a several-fold increase of the critical heat flux. However, critical heat flux in nanofluids depends on the material and size of nanoparticles as well as on the diameter of used cylindrical heater. It is shown that the critical heat flux increases with increasing the nanoparticles size, while it decreases with increasing the heater diameter. It was revealed for the first time that the critical heat flux depends on the boiling process duration.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
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