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Nucleophilic substitution of hydrogen (SNH) in 2-aryl-1,2,3-triazole 1-oxides proceeds by treatment with pentafluorophenyllithium according to the addition—elimination scheme (SNH AE) with the formation of the corresponding 4-pentafluorophenyl-1,2,3-triazoles with yield 72–78%. Calculation methods (determining the Fukui function and Gibbs energy) were used to establish that the presence of electron-withdrawing groups in the triazole ring does not increase the yield of the target product. Most likely, this can be explained by the shielding of the reaction center by electron clouds of conjugated nitrogen atoms. [ABSTRACT FROM AUTHOR]

The main problems and features of the study of two-phase flows are considered. The main methods for the mathematical modeling of two-phase flows, which describe the interface boundary, interface interactions, and turbulence of the carrier phase at different hierarchical levels, are briefly described. Some of the latest research results on two-phase flows with solid particles, droplets, and bubbles are described and analyzed: effective methods of thermal protection of power propulsion systems operating on solid fuels; determining the contribution of carbon nanoparticle condensation to the combustion and detonation of gaseous hydrocarbons; aircraft anti-icing methods; specific features of the development and stability of a spray plume; acoustic wave propagation in multifractional polydisperse vapor–gas–droplet mixtures of gas with solid particles; development of detonation waves in a bubbly liquid; and many others. [ABSTRACT FROM AUTHOR]

Transformations of the various 6-[4-(methylthio)phenyl]-3-(2-pyridyl)-1,2,4-triazines in their reactions with an aryne intermediate were investigated. It was shown that the interaction of a 5-unsubstituted triazine with the aryne led to an S-arylation product, whereas there were no any transformations of the pyridyltriazine system. Introduction of the pentafluorophenyl substituent at the C(6) position of the triazine changed the pathway in this reaction with the aryne, which proceeded simultaneously at two reaction centers. In particular, there were a rearrangement of the 3-(2-pyridyl)-1,2,4-triazine into the 10-(1H-1,2,3-triazol-1-yl)pyrido[1,2-a]indole system as well as S-arylation. The product of dual functionalization, 10-{5-perfluorophenyl-4-[4-(phenylthio)phenyl]-1H-1,2,3-triazol-1-yl}pyrido[1,2-a]indole, exhibited a blue emission at λem = 395 nm and a fluorescence quantum yield comparable to the analogs obtained previously. [ABSTRACT FROM AUTHOR]

A convenient approach towards previously unknown phosphonium salts containing a non-aromatic 2H-imidazole moiety is reported. The approach is based on a direct nucleophilic C(sp2)-H functionalization of 2H-imidazole 1-oxides with triphenylphosphine acting as a nucleophile. Herewith, the heterocyclic N-oxide moiety is utilized as an auxiliary group contributing to an abstraction of C-H proton during the elimination process. Newly obtained compounds can be a subject of further modification, e.g. used for the synthesis of monodeuterated 2H-imidazoles. [ABSTRACT FROM AUTHOR]

A five-stage method for the synthesis of Y-shaped push–pull fluorophores based on 2-(4'-methoxyphenyl)-1,2,3-triazole was proposed. The resulting molecules exhibited emission in the range from 350 to 450 nm with high quantum yields (QY) of 90–99% in solvents of various polarity. The products proved to be applicable as chemosensors for both aromatic and aliphatic nitro analytes in concentrations down to 300 ppb. [ABSTRACT FROM AUTHOR]

This paper presents experimental data on the ignition induction period of synthetic hydrocarbons at various temperatures and pressures obtained using a shock tube. The experimental results were used to determine the influence of the ignition induction period on the combustion efficiency of hydrocarbons in high-enthalpy flows for diffusion-kinetic regimes An integral mathematical model is presented that takes into account the influence of the kinetic factors of ignition and combustion on the efficiency of physicochemical processes in air flow. The results of calculating the combustion efficiency of synthetic hydrocarbons in flows with different parameters are given. [ABSTRACT FROM AUTHOR]

The refractory metal carbides TiC, ZrC, HfC, NbC, and TaC have excellent physical, chemical, and mechanical properties as materials for ultra-high temperature ceramics. The most refractory of them are TaC and HfC, the melting temperatures of which approach 4000°C. The high hardness, strength, and wear resistance of refractory carbides is also noteworthy. Therefore, natural interest in high-entropy carbides (HECs) based on them is grounded: they are becoming an important class of new ceramic materials, since they potentially have more advanced applied properties. However, the production of such materials by classical metallurgical methods is a difficult problem. In modern investigations, HEC samples are most often synthesized using expensive special equipment (plasma spark sintering methods, high-energy planetary mills, etc.) and relatively long preparation of precursors for sample fabrication. Here, we describe a new approach to synthesizing a multicomponent (Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)C carbide using an electrochemical process at a temperature not exceeding 1173 K. This technique is based on the phenomenon of currentless metal transfer in molten salts. After sequential metal transfer, the sample is washed from an electrolyte and then sintered in a vacuum furnace. According to X-ray diffraction analysis, the resulting HEC is a single-phase fcc solid solution. The X-ray diffraction pattern of the synthesized sample is in good agreement with the X-ray diffraction pattern calculated by the Debye formula for a supercell of 64 000 atoms. A compacted HEC sample is prepared by pressing a pellet 10 mm in diameter in a mold with the addition of cobalt as a matrix metal. After vacuum sintering, the sample is polished for examination in a scanning electron microscope. Elemental mapping of the sample surface is performed; it demonstrates a satisfactory distribution of the metals that make up the HEC. The measured microhardness of the sample turned out to be lower than the values reported by other authors, which can be due to some residual porosity of the sample. [ABSTRACT FROM AUTHOR]

We have studied for the first time the feasibility of using Al2O3 and Al : Zn (1 : 1) coatings produced by supersonic plasma spraying for protecting GdTbDyHoSc and GdTbDyHoY high-entropy rare-earth (RE) alloys from corrosion in a salt-fog chamber. The results demonstrate that, under salt fog conditions, Al2O3 coatings break down through local surface activation, resulting in pitting corrosion, with a considerable fraction of the coating on the main material remaining intact. The alloys coated with Al : Zn (1 : 1) exhibit lower corrosion resistance under salt fog conditions as a consequence of electrochemical corrosion. Interaction of Al2O3 with NaCl limits the suitability of such coatings for protecting high-entropy RE alloys under salt fog conditions. Limitations refer to the specimen test time and coating thickness. [ABSTRACT FROM AUTHOR]

A procedure has been developed for the direct Csp2–H functionalization of phenanthridine with a 1H-benzotriazole residue in the presence of Selectfluor® to build up Csp2–N bond. The procedure makes it possible to synthesize 6-(1H-benzotriazol-1-yl)phenanthridine in one step using commercially available starting materials and reagents. The product is an important substrate for further chemical transformations. [ABSTRACT FROM AUTHOR]

The article discusses the 60th anniversary of the journal High Temperature and its focus on research in the fields of heat and mass transfer and physical gas dynamics. The journal has published numerous articles on various topics, including forced convection, free convection, heat transfer during chemical transformations, boiling, evaporation, and condensation, heat transfer in two-phase flows and porous media, heat transfer intensification, radiation, and complex heat transfer, and applied problems. The article highlights specific studies conducted in each area, showcasing the diverse range of research published in the journal. The article concludes by acknowledging the journal's longstanding reputation and expressing hope for its continued success in the future. [Extracted from the article]

Previously, we identified a new immunoregulatory factor, the production of which provides rats with resistance to certain experimental autoimmune diseases. It has been named regulatory rheumatoid factor (regRF). RegRF inhibits the expansion of CD4 T lymphocytes by killing activated cells. CD4 T cells are essential for antibody production against a majority of antigens and for the generation of cytotoxic T cells; therefore, regRF is an attractive therapeutic biotarget for T-cell and antibody-mediated autoimmune diseases. RegRF is anti-idiotypic antibodies that have a shared paratope in addition to an individual paratope. Epitopes specific to the shared regRF paratope (regRF epitopes) can be obtained on conformers of IgG Fc fragments. Immunization with Fc fragments carrying regRF epitopes reduces rat collagen–induced arthritis and diminishes experimental autoimmune encephalomyelitis. The aim of this study was to determine whether IgG Fc fragments bearing regRF epitopes suppress experimental autoimmune thyroiditis (EAT). Four weeks after EAT induction, rats were immunized with IgG Fc fragments exhibiting regRF epitopes. Histology studies of the thyroid were performed 4 weeks later. Thyroid function and other parameters were also evaluated. Treatment of rats with Fc fragments bearing regRF epitopes decreased the number of rats affected by EAT, significantly decreased the extent of thyroid damage, prevented thyroid metaplasia, and restored normal thyroid hormone production. Therefore, RegRF is a promising biotarget in autoimmune thyroiditis, and Fc fragments bearing regRF epitopes are a potential therapeutic agent for that condition. [ABSTRACT FROM AUTHOR]

An attempt is made to experimentally study some of the effects observed during the gravitational deposition of drops on a model with a hemispherical end. By a frame-by-frame analysis of video recordings, the features of the interaction of the drops with the surface of the model are analyzed. Data are obtained on the velocities and sizes of both small (secondary drops) and large (fragments) drops in the case of a high (close to the dynamic Leidenfrost temperature) temperature of the model. The effect of the formation of drops with near-zero velocities near the surface of the model as a result of the coagulation and momentum exchange of incident and reflected drops is revealed. Data are obtained on the decrease in the velocity recovery coefficient with an increase in the inertia of drops in the case of their interaction with curved surfaces. The effect of the noncoincidence of the points of contact and rebound (detachment) of drops from the surface, which increases with increasing drop size, is found. [ABSTRACT FROM AUTHOR]

Based on a two-parameter k–ε model of turbulence for a two-phase flow, the effect of macro-, micro-, and nanoparticles on the intensity of carrier gas turbulence is analyzed. An expression is obtained that predicts the effect of particles of different inertia on the value of the turbulence energy of the carrier phase. It is shown that the turbulent effect of extremely low-inertia particles (nanoparticles) is replaced by the laminarizing effect of low-inertia particles (microparticles), and then again changes to the turbulent one due to the additional generation of turbulence in wakes behind large particles (macroparticles). [ABSTRACT FROM AUTHOR]

The characteristics of a flow formed behind a large particle moving in a descending turbulent air flow in a duct was measured using the PIV method, which makes it possible to record the instantaneous velocity fields. Data on deformation of the field of the instantaneous air velocity in a turbulent wake behind a large particle are presented and analyzed. [ABSTRACT FROM AUTHOR]

This article discusses the results of studies carried out in recent years by a team of scientists from the Postovskii Institute of Organic Synthesis, Ural Branch, Russian Academy of Sciences, in cooperation with the First President of Russia Boris Yeltsin Ural Federal University, Ural State Medical University, Volgograd State Medical University, and other scientific and production organizations of the country to create triazavirin (riamilovir) and other direct etiotropic antiviral drugs based on azaheterocyclic derivatives. [ABSTRACT FROM AUTHOR]

This paper presents the results of measurements of the solid particle concentration field near a frontal point of a cylindrical body with a flat end. We restore the particle concentration fields based on their image identification obtained by photographic fixation at low shutter speeds. The experiments revealed the effect of increasing the particle concentration near the body surface, which appears more clearly with the increase in the local particle concentration in the oncoming flow. We analyze the mechanisms of the particle concentration increase in the flow around bodies by flows containing particles. [ABSTRACT FROM AUTHOR]

This study was aimed at analyzing the relations of metastasis to regional lymph nodes (RLNs) with histopathological indicators of invasive breast carcinoma of no special type (IC-NST) and its cytokine profile. Enzyme-linked immunosorbent assays were performed to determine concentrations of IL-2, IL-6, IL-8, IL-10, IL-17, IL-18, IL-1β, IL-1Ra, TNF-α, IFN-γ, G-CSF, GM-CSF, VEGF-A, and MCP-1 in the culture supernatant of IC-NST samples from 48 female patients. Histopathological indicators (degree of tumor cell differentiation, mitoses, and others) and ER, PR, Her2/neu, Ki-67, and CD34 expression levels were determined. By means of three types of neural network models, it was shown that for different parameters of the output layer, different groups of parameters are involved that have predictive value regarding metastasis to RLNs. As a result of multi-dimensional cluster analysis, three clusters were formed with different cytokines profiles of IC-NST. Different correlations between indicators of cytokine production by IC-NST and its histopathological parameters were revealed in groups with different cytokine profiles. It was shown that at simultaneous evaluation of the production of even two cytokines, the importance of which relationship with metastasis was revealed by neural network modeling, can increase the probability of determining the presence of metastasis in the RLNs. [ABSTRACT FROM AUTHOR]

A relation that takes into account all the main mechanisms of the effect of particles on gas turbulence is obtained for the first time using the two-parameter turbulence model for a two-phase flow. The expression found makes it possible to analyze the effect of particles on the turbulence energy of the carrier phase in a wide range of inertia. It is shown that the turbulizing effect of extremely low-inertia particles (nanoparticles) is replaced by the laminarizing effect of low-inertia particles (microparticles), and, then again, is replaced by the turbulizing effect due to the additional generation of turbulence in the wakes behind large particles (macroparticles). [ABSTRACT FROM AUTHOR]

The selection of the inertial parameters (density, size) of tracer particles used for the diagnostics of high-speed gas flows is considered. A relation has been obtained from an analysis to find the velocity of tracer particles under the assumption that the aerodynamic drag coefficient of the particles is equal to unity. Estimates of the times and lengths of the acceleration of particles with different inertia in a gas flow moving at a constant speed are made. [ABSTRACT FROM AUTHOR]

Differences in the production of cytokines by tumor biopsy specimens were revealed depending on the pathological prognostic stages of The American Joint Committee on Cancer (AJCC) of invasive nonspecific breast carcinoma (INBC). The patients with a predominant absence of metastases in combination with a triple negative molecular subtype differ from the patients with other pathological prognostic stages in the cytokine-producing tumor resource of IL-18, IL-1β, IL-1Ra, TNF-α, GM-CSF, and MCP-1. [ABSTRACT FROM AUTHOR]

Currently, the data on the presence of adenoviral receptors in fish are very limited. We used mouse recombinant adeno-associated viral vectors (rAAV) with a calcium sensor GCaMP6m, which are typically used for the CA1 region of the mouse dorsal hippocampus but have not previously been used for gene delivery in the fish brain. The aim of this work was (1) to assess the ability of the mouse hippocampal rAAV to label brain cells in a juvenile chum salmon Oncorhynchus keta and (2) to determine the phenotype of rAAV-labeled cells. In vivo gene delivery was carried out through intracranial injection of the GFP-tagged rAAV directly into the mesencephalic tegmentum of a yearling chum salmon. The level of infectious efficacy was assessed 1 week after the injection of the vector. Using confocal scanning microscopy, rAAV-GFP expression was assessed in various tegmental areas of a juvenile O. keta, followed by the localization of the neuron-specific protein HuCD tagged with red-fluorescent Alexa Fluor 546. An immunohistochemical analysis combined with DAPI staining revealed rAAV/HuCD colocalization in various neurons of the mouse mesencephalic tegmentum. This finding provides evidence that rAAV-expressing tegmental cells in the juvenile chum salmon refer to a neuron-specific line of brain cells, indicative of the ability of mammalian hippocampal adenoviruses to infect neurons of the fish central nervous system. Thus, mammalian hippocampus-specific rAAVs can incorporate into fish brain neurons with subsequent expression of the viral proteins. It appears that tegmental neurons in a juvenile chum salmon contain a homologue of the mammalian adenoviral receptor. [ABSTRACT FROM AUTHOR]

The results of research on identification of bird species involved in collisions mainly with aircraft of the Aeroflot–Russian Airlines Public Joint-Stock Company are presented. Identification examination as a complex study includes DNA analysis, as well as examination of the macro- and microstructure of a group of feathers, a single feather, or a fragment of one. The bird strike location is established. The reasons and factors leading to the appearance of a species at the airfield are considered, and brief recommendations are given to minimize bird strikes at the airfield. During this period, 32 species of ten bird orders involved in strikes were identified. It was found that most collisions occurred with the orders Charadriiformes (mostly with gulls), Falconiformes, and Apodiformes. It is noted that more than 90% of collisions occur at the airport or in its vicinity; there are half again as many more strikes during taking off than during landing. The largest number of collisions takes place in spring and summer time and during daylight hours. The engine, nose cone, and fuselage mainly suffer from bird collisions. [ABSTRACT FROM AUTHOR]

The computational–theoretical and experimental works on the characteristics of particle-laden boundary gas flows are reviewed. The features of particle motion in laminar and turbulent boundary flows and their feedback on the gas flow are considered. The available studies of the stability of the laminar boundary layer and the effect of particles on the laminar-to-turbulent transition are analyzed. [ABSTRACT FROM AUTHOR]

The computational-theoretical and experimental works on different types of two-phase flows are reviewed. The problems of two-phase flows and features of their study are considered. The basic characteristics of two-phase flows and the methods of their simulation are provided. The results of the study of two-phase flows with solid particles, droplets, and bubbles are outlined and analyzed. [ABSTRACT FROM AUTHOR]

This article provides a brief review of concepts of the features of the pre- and postnatal development of the central nervous system in vertebrates. Particular attention is paid to questions of the origins of neuron populations at different periods of nervous system development. Neuron and glial populations are shown to arise from different sources: neural stem cells (NSC) give rise to the neurogenic epithelium by vertical migration in the brain wall, while closer to birth, their successors give rise to cells of the so-called radial glia (RG) and intermediate precursor cells (IPC). Replenishment of the neuron population in some parts of the brain occurs as a result of tangential migration of neuroblasts from the neurogenic zones located at great distances from the final site of neuron differentiation. The processes of neuro- and gliogenesis are affected by a large number of different growth, neurotrophic, and transcription factors. Questions of the features of postnatal neurogenesis in the adult nervous system in vertebrates and the potential of using model objects for studying this process in humans are discussed. [ABSTRACT FROM AUTHOR]

The relationship between the content of supernatant cytokines and the immune histochemical (IHC) expression of epithelial-mesenchymal transition (EMT) markers was studied in biopsy samples of invasive breast carcinoma of no special type (IBC-NST) from patients with and without lymphatic spread of metastases (group II and group I, respectively). The concentrations of TNF-α, IFN-γ, G-CSF, GM-CSF, VEGF, MCP-1, IL-2, IL-4, IL-6, IL-8, IL-10, IL-17, IL-18, IL-1β, and IL-1Ra, as well as the immunohistochemical (IHC) expression of EMT markers cadherin-E (CDH1), β-1 integrin (CD29) and type II collagen (CII) were assayed. Results have shown that the patients of these groups statistically significantly differed by spontaneous production of IL-18 and G-CSF, and by the index of the polyclonal activator influence (IPAI) on G-CSF production. The study of relationships between supernatant cytokine production and the IHC expression by biopsy samples revealed correlations between the parameter of CII expression in the tumor tissue and the cytokine production by tumor biopsy specimens; these correlation links were typical for all IBC-NST patients, while correlation links (both direct and reverse ones) between CDH1, CD29, and cytokine production varied in groups of patients with and without lymphatic spread of metastases. The study revealed the features of the correlation links between the cytokine production by the tumor, its microenvironment and the IHC expression of EMT markers in IBC-NST patients with and without lymphatic spread of metastasis. [ABSTRACT FROM AUTHOR]

With the use of high-speed video filming, the effect of the appearance of droplets with near-zero velocities in gas–droplet flows past bodies was discovered for the first time. The formation of levitating droplets occurred as a result of the coalescence of droplets falling and reflected from the model. It has been suggested that the main mechanism for the appearance of drops with near-zero velocities is momentum exchange as a result of the collision of droplets with opposite directions and values of velocity close in magnitude. The effect of an increase in the size of large levitating drops due to the coalescence of falling droplets with them due to multiple collisions has been detected. [ABSTRACT FROM AUTHOR]

The spontaneous and polyclonal activator-stimulated cytokine production by immunocompetent blood cells, the tumor and its microenvironment, as well as the state of the extracellular matrix were investigated in 95 patients with invasive breast carcinoma of no special type (IBC-NST) with lymphatic metastases. Concentrations of IL-2, IL-4, IL-6, IL-8, IL-10, IL-17, IL-18, IL-1β, IL-1Ra, TNF-α, IFN-γ, G-CSF, GM-CSF, VEGF and MCP-1 were determined by the ELISA method. Evaluation of extracellular matrix included the state of the fibrous component, the content of neutral glycoproteins and sulfated glycosaminoglycans. Regional lymph node metastases were found in 35 of 95 patients. The study showed that in the presence or absence of lymphogenous metastasis, the index of the influence of polyclonal activators (IPAI) on cytokine production by immunocompetent blood cells differed in three parameters (IL-6, IL-8 and IL-1β), while IPAI on the production of cytokines by tumor cells and its microenvironment differed in two (IL-2 and IL-17). The presence of lymphatic metastases corresponded to an increase in the spontaneous production of cytokines, while their absence corresponded to an increase in the production stimulated by polyclonal activators. The IAPI values on cytokine production by immunocompetent blood cells demonstrate the high stimulating effect of the polyclonal activators, while the IPAI values on cytokine production tumor cells and tumor microenvironment suggest low (if any) effect of polyclonal activators. Based on the data obtained, the ratio of the IPAI values is proposed for evaluation of probability of lymphatic metastases in the preoperative period. Evaluation of the extracellular matrix revealed a threshold, which in 100% of cases demonstrated the correspondence of the state of the extracellular matrix to the presence of metastases in the regional lymph nodes. Based on the results of this study, we proposed a risk group for metastasis among women lacking lymph nodes metastases at the time of the study. [ABSTRACT FROM AUTHOR]

In most cases, breast cancer is a malignant neoplasm associated with infiltration of a tumor with the cells that form its microenvironment and produce various cytokines. The aim of the study was to evaluate the cytokine-producing function of tumor cells and their microenvironment in biopsy samples of patients with invasive breast carcinoma of no special type (IBC-NST; group I) and in patients with benign breast diseases (BBD, group II). Patients of group II were further divided into group IIa, which included patients only with fibroadenoma, and group IIb, which included patients with leaf-shaped fibroadenoma, fibroadenomatosis, fibrocystic mastopathy, intraductal papillomatosis and sclerosing adenosis and fibrocystic mastopathy microcalcifications. Concentrations of IL-2, IL-6, IL-8, IL-10, IL-17, IL-18, IL-1β, IL-1Ra, TNF-α, IFN-γ, G-CSF, GM-CSF, VEGF, and MCP-1 were measured in supernatants of breast biopsy samples. The cytokine-producing activity of tumor biopsy samples and its microenvironment was assessed by the index of the polyclonal activator influence (IPAI) on cytokine production. Comparison of groups I and II, revealed high IPAI values on production of IL-17, IL-18 and TNF-α in BBD patients (group II). Higher IPAI values on production of IL-18, TNF-α, and IL-1β and the ratio of IL1β/IL1Ra were observed in BDD patients with fibroadenoma as compared to IBC-NST patients. No statistically significant differences in the IPAI values were found between groups I and IIb. This suggests the existence of changes in the mammary gland in patients of group IIb similar to those in breast carcinoma (IBC-NST) patients. Comparison of groups IIa and IIb revealed higher IPAI values in group IIa (fibroadenoma) patients on production of IL-1β, as well as the ratio of IL1β/IL1Ra. The results of this study have shown some features of the cytokine-producing resource of breast biopsy samples from patents with IBC-NST and BDD. [ABSTRACT FROM AUTHOR]

The material of patients with invasive carcinoma of no special type (ICNT) and nonmalignant diseases (ND) of the mammary gland was studied. When comparing the concentrations of histidine-rich glycoprotein (HRG) and E-cadherin (CDH1), statistically significant differences between ICNT and ND by HRG in the supernatant of blood cells and its spontaneous production by biopsies and by CDH1 at its induced production, as well as by influence indices of polyclonal activators on the production of CDH1 were found. When comparing the expression of immunohistochemical markers, no statistically significant differences between ICNT and ND were obtained. [ABSTRACT FROM AUTHOR]

This paper is aimed to demonstrate an opportunity of the generation of nonstationary wall-free fire whirls under laboratory conditions without using mechanical swirling devices and to estimate their integral parameters. A simple experimental facility, making possible the generation of concentrated fire vortex structures by means of combustion of solid fuel (urotropine) arranged symmetrically on a metallic underlying surface, is described. With the use of photography, some novel data on the probability of generation of fire whirls depending on the experimental mode have been obtained. [ABSTRACT FROM AUTHOR]

The problems and features of an accounting of the collisions of particles (droplets) in turbulent two-phase flows are considered. The developed approaches for the determination of collision nuclei of monodisperse and bidisperse particles (droplets) in uniform isotropic turbulence, as well as under the combined action of turbulence, averaged velocity gradient, and gravity, are described. The results of experimental and theoretical calculations of the effect of collisions on the characteristics of two-phase jet flows and flows in channels are presented and analyzed. [ABSTRACT FROM AUTHOR]

We consider aspects of using the method of anemometry on particle images to measure the velocity fields of nonstationary air vortices. To prevent the loss of a cross-pair when a particle passes through a light curtain, a method is proposed for determining the time delay between frames. Methods for measuring the velocity fields of nonstationary air vortices are described taking into account the vertical velocity of particles when the actual velocity is reproduced from the measured horizontal projection in the case of using a two-dimensional (single-chamber) type of anemometry method. [ABSTRACT FROM AUTHOR]

The article focuses on the influence of human leukemia differentiation factor (HLDF), carcinoembryonic antigen (CEA), and polyclonal activators (PA) on cytokine production by peripheral blood cells in breast cancer and benign breast diseases. It was found that the influence of internal factors on the production of cytokines by the peripheral blood cells is associated with lymphatic metastasis (CEA: IL-10; HLDF: IL-6, IL-1β, TNF-α, and G-CSF). One special circumstance was that there were no differences between the production of cytokines by peripheral blood cells in the patients with breast cancer compared to the patients with benign breast diseases with a high risk of malignant transformation. This is evidence of the functional similarity of peripheral blood cells in patients with these conditions. Cytokine production under the influence of PA was different only in case of TNF-α in all study groups. [ABSTRACT FROM AUTHOR]

Expression of cystathionine β-synthase (CBS) in the brain of adult trout under normal conditions and 1 week after an eye injury was assessed using Western blot analysis. The study of CBS distribution in the brain of intact trout and after a mechanical eye injury in the telencephalon, tectum, cerebellum, and brainstem was carried out by the method of immunoperoxidase labeling on free-floating sections. The results of the study showed an increase in CBS expression in different brain divisions after an eye injury. In the visual projection center of the brain (tectum), radial glia cells expressing CBS were revealed after the injury. The emergence of CBS+ heterogeneous radial glia in the trout tectum after eye injury indicates the ability of the reactive neural stem cells (NSC) to synthesize hydrogen sulfide. CBS+ fibers and cells were found in the proliferative zones of cerebellum (valvula) and telencephalon (ventral region). In the intact trout tegmentum, CBS expression was observed in large neurons of the dorsal region and in the proliferative zones. After the eye injury, reactive neurogenic niches appeared in the brainstem, and no CBS-immunopositivity was detected in the periventricular zone. The increased expression of H2S-producing CBS enzyme after a traumatic impact can probably be explained by the neuroprotective functions of hydrogen sulfide, which are implemented in the matrix zones of the brain associated with reparative neurogenesis. A cultivation of trout brain cells showed the formation of neurosphere-like complexes, a part of which exhibited CBS-immunopositivity in the monolayer. [ABSTRACT FROM AUTHOR]

Processes of proliferation and constitutive neuro- and gliogenesis in the mesencephalic tegmentum of intact juvenile chum salmon, Oncorhynchus keta, and at 3 days after a traumatic injury were studied by immunohistochemistry (IHC) labeling of PCNA, HuCD, and GFAP. In the chum tegmentum, the proliferative activity was revealed both in separate cells and in small cell clusters of the periventricular zone (PVZ). The presence of constitutive neurogenic zones provides the processes of persistent brain growth. After damage to the tegmentum, proliferation in PVZ is activated, the constitutive neurogenic zones reactivate, reactive neurogenic niches form in the parenchyma, and the proliferative activity is also initiated in the centers of secondary proliferation (basal tegmentum). It was first found that traumatic damage to the tegmentum leads to accelerated differentiation of neurons in the subventricular zone (SVZ) and dorsomedial tegmentum as well as to the appearance of HuCD+ cells with the ependymo- and radioglial phenotype in SVZ, which are absent in intact animals. It was first shown that the local foci of posttraumatic neurogenesis, located in the reticular formation parenchyma, and the zones of posttraumatic gliosis, which contribute to a more efficient process of cell migration to the injury area, are formed as a result of tegmentum damage. The data obtained provide new information on the constitutive biology of neural stem cells and their involvement in brain regeneration. [ABSTRACT FROM AUTHOR]

The distribution of the Pax2+ transcription factor in the optic nerve after a mechanical eye injury on the side of damage and in the contralateral nerve has been studied in the trout Oncorhynchus mykiss. It has been found that injury of the optic nerve in this fish species causes Pax2+ reactive astrocytes involved in the initial stages of optic nerve axon regeneration to increase in number, especially in the area of the head and the proximal part of the optic nerve. As the optic nerve in trout is damaged, a significant growth of the heterogeneous population of Pax6+ cells occurs in the brain divisions that have direct retinal inputs, diencephalon, and optic tectum. A part of the Pax6+ cells have an undifferentiated phenotype and are a component of reactive neurogenic niches located in the periventricular zone and parenchymal regions of the brain. Another population of Pax6+ cells has the radial glial phenotype and appears as a result of activation of the constitutive neurogenic domains also within the newly formed reactive neurogenic niches. Thus, due to the optic nerve injury, a pronounced neurogenic response associated with the appearance of reactive neurogenic niches and radial glia arises both in the brain divisions with direct retinal projections and in those lacking the retinal projections as well as in remote regions. The results obtained indicate that the damage to the optic nerve causes an increased reactive neurogenesis in the brain of adult trout. [ABSTRACT FROM AUTHOR]

Substituents effects in cyclic diene derivatives are studied using quantum chemical modeling and compared to the corresponding effects in aromatic (benzene) and fully saturated (bicyclo[2.2.2]octane) compounds. In particular, electronic properties of the fixed group Y in a series of 3- and 4-X-substituted cyclohexa-1,3-diene-Y derivatives (where Y = NO2, COOH, COO− OH, O−, NH2, and X = NMe2, NH2, OH, OMe, Me, H, F, Cl, CF3, CN, CHO, COMe, CONH2, COOH, NO2, NO) are examined using the B3LYP/6-311++G(d,p) method. For this purpose, quantum chemistry models of the substituent effect: cSAR (charge of the substituent active region) and SESE (substituent effect stabilization energy) as well as traditional Hammett’s substituent constants (σ) and their inductive (F) and resonance (R) components are used. π-electron delocalization of the transmitting moiety (butadiene fragment of the CHD) is described by the HOMA index. This comparative study reveals interplay between inductive and resonance contributions to the substituent effect. [ABSTRACT FROM AUTHOR]

The paper presents a review of theoretical and experimental works devoted to two-phase (gas-solid) flows past bodies. The particularities of particle motion in the vicinity of bodies of various shapes and the influence of the disperse phase on the drag force and heat transfer are considered. Some consequences of the interaction of particles with body surfaces (erosive destruction, gasdynamic spraying, icing, and glowing) are analyzed. [ABSTRACT FROM AUTHOR]

The first results of physical simulation of the effect of gas injection on the characteristics of gas stream with solid particles at flow around bodies are presented. The possibility of ensuring an effective protection of the body surface from the negative effects of particles (droplets) is demonstrated. A dimensionless criterion (the Stokes number) is proposed that characterizes the inertia of particles near the critical point of the body and the intensity of their deposition on the surface under injection conditions. [ABSTRACT FROM AUTHOR]

Characteristics of the process and heat transfer of subcooled water boiling on mesostructured surfaces obtained by microarc oxidation of titanium foil with formation of a TiO layer and deposition of AlO particles from boiling nanofluid have been experimentally investigated. The experiments have been carried out in the forced flow of deaerated water in a vertical rectangular channel, 21 × 5 mm in size. The ranges of regime parameters are as follows: water mass velocity is up to 650 kg/(m2 s), subcooling is 30-75°C, pressure is ~10 Pa, and heat flux rate is 0.7-5.0 MW/m. It is established that the number of active nucleation sites is (70-80) × 105 1/(m s) at the heat flux of 1.5-2.0 MW/m. Significant subcooling of the liquid and good wettability of the structured surface provide intense deactivation and lead to random spatial distribution of the nucleation sites. The characteristic size of vapor bubbles is about 200-250 μm and the bubble lifetime is 200-500 μs. Application of the coating prepared by microarc oxidation enhances heat transfer by 20-30%. At high subcoolings of liquid, the characteristics of boiling on smooth surfaces and surfaces with the coating were fairly close. [ABSTRACT FROM AUTHOR]

A superficially located periventricular proliferative area with PCNA-immunopositive (PCNA+) cells, which corresponds to the pallial periventricular zone (PVZ) of other fish species, including its dorsal, lateral, and medial compartments, is discovered in the telencephalon of the juvenile masu salmon Oncorhynchus masou. The PCNA+ cells are also identified in the parenchyma of the masu salmon intact brain, and their maximum concentration is observed in the medial zone. After a mechanical injury, the zones of induced neurogenesis-neurogenic niches and sites of secondary neurogenesis surrounded by radial glial fibers-appear in the masu salmon telencephalon. The PVZ of the juvenile masu salmon pallium contains clusters of undifferentiated HuCD-immunopositive (HuCD+) neurons. A change in the HuCD+ cell topography is observed in the mechanically injured masu salmon telencephalon, namely, neurogenic niches in the lateral zone and an increase in the cell distribution density and cell migration patterns in the medial zone. A high level of persistent neurogenesis is characteristic of the juvenile masu salmon brain. [ABSTRACT FROM AUTHOR]

The objective of this work was to study proliferation processes and the role of glia and neural stem cells in the event of injurious action on cerebellum of masu salmon's ( Oncorhynchus masou) juvenile. Using the immunoperoxidase staining of the glial fibrillary acidic protein (GFAP) and proliferating cells nuclear antigen (PCNA), processes of proliferation and gliogenesis after mechanical trauma of cerebellum of cherry salmon's ( Oncorhynchus masou) juvenile were studied. After the trauma, the intensity of proliferation and migration processes varies in different zones. Proliferation processes decrease after the trauma in lateral and basal zones, and migration increases. In the dorsal zone, on the contrary, migration processes significantly decrease and proliferation increases. In the dorsal matrix zone of a cerebellum, intense cell proliferation was detected. In the dorsal, lateral, and basal zone of the molecular layer of cerebellum after traumatic damage, neurogenic niches containing PCNA and cells, as well as a heterogeneous population of PCNA-cells, were identified. At the location of neurogenic niches, fibers of radial glia and small single intensely or moderately labeled GFAP cells were discovered. As a result of damaging action, GFAP+ fibers of radial glia, which form differently directed radially oriented bundles, appeared in the dorsal matrix zone. Such structural formations have not been discovered in intact animals. We suppose that, after the trauma, structural reconstruction connected with partial spatial reorientation of the radial glia fibers and formation of specific directions for cells formed in this zone occurs in the dorsal matrix zone. As a result of the trauma, in masu salmon's cerebellum, elements of the radial glia, including both cells possessing typical morphology and cell fragments presented as long radially oriented processes or cell body containing initial fragments of radial fibers, appeared. [ABSTRACT FROM AUTHOR]

Structure of three 6-aryl-5-pentafluorophenyl-2,2'-bipyridines has been studied by means of single-crystal X-ray diffraction analysis. The effect of some functional fragments on the structural organization of compounds, in particular, donor and acceptor substituents in the aryl moiety, as well as annulated benzene and cyclopentane rings on the molecular structure and crystal packing of pentafluorophenyl-modified 2,2'-bipyridine ligand systems has been analyzed. [ABSTRACT FROM AUTHOR]

In this work, our discovery for the first time of a two-spiral nonstationary structure of interacting vortex filaments preceding the generation of a wall-free nonstationary air vortex is described. [ABSTRACT FROM AUTHOR]

Computational and theoretical works devoted to studying the generation and dynamics of air tornado-like vortices are reviewed. Currently developed approaches to mathematical modeling of the main characteristics of vertical atmospheric vortices are presented. [ABSTRACT FROM AUTHOR]

It is demonstrated that free concentrated fire whirls can be physically modeled if the outer circulation is absent. Vortex structures were generated when hexamethylenetetramine pellets, located axially on a substrate (aluminum sheet) burned. The first data on specific features of fire whirl formation and some integral parameters (the lifetime, height, and diameter) were obtained using video shooting. [ABSTRACT FROM AUTHOR]

The experimental works devoted to studying the generation and dynamics of concentrated air and fire vortices are reviewed. The main characteristics of stationary and nonstationary vortices, as well as free and confined air and fire vortices, are considered. [ABSTRACT FROM AUTHOR]