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Data regarding the solubility of salts in the KNO3–KH2PO4–K2SO4–H2O system can be used to optimize the composition of liquid complex fertilizers. This research considers phase equilibria in the quaternary system KNO3–KH2PO4–K2SO4–H2O at 298.2 K for the first time. A phase diagram with a plotted grid of isohydric lines was constructed based on the results of the experiment. The phase diagram displays a single quaternary invariant point, three ternary invariant points, three univariant curves, and three crystallization regions that correspond to KH2PO4, K2SO4, and KNO3. Among these, the crystallization region of K2SO4is the largest, while that of KNO3is the smallest. The order of decreasing solubility for the salts is KNO3> KH2PO4> K2SO4. No crystalline hydrates, double salts, or solid solutions were found in the system. The solution that is maximally saturated with salts corresponds to the quaternary invariant point.

A systematic investigation of the emerging toroidal vortex flow formation in a long-lived plasmoid composed of a high-current pulse atmospheric discharge with an electrolytic anode was carried out by using a particle image velocimetry (PIV) setup, as well as a specially assembled laser light sheet visualization system. More specifically, a laser light sheet imaging method of the investigated vortex flow was carried out by using a powerful green laser, which formed a flat divergent beam. The reflection of the laser beam reflected from dust particles in the atmosphere or from the smallest droplets of water vapor, especially prelaunched into the discharge zone to improve the contrast, rendered the visualization of the gas flow feasible, which was then recorded by a video camera. From our analysis, it was demonstrated that the emerging long-lived plasmoid gradually acquired a characteristic ring shape from the initial spherical shape and was able to maintain its volume for several hundred milliseconds after switching off the discharge current due to the formation of a vortex structure. The proposed method of measuring the particle image velocity made it thus possible to determine the velocity and direction of the flow in the formed toroidal vortex structure of the plasmoid.

Forest is a multilayered canopy, where overstory and understory implement different biogeochemical cycles, phenology, and functional role. Remote sensing products typically estimate forest total leaf area index (LAI), while few quantify its components. The theoretical understanding of foliage distribution between layers is still quite limited. In this study, we have developed a semiempirical model for decomposition of forest total LAI between layers. Decomposition was implemented over the full extent of Russian forests, exhibiting a wide dynamic range of the forest total LAI. This article addresses both the theoretical and practical aspects of the problem. In terms of theory, we formalized the principles of forest layers “biological/ radiometric coupling into a parametric model allowing to analyze the relationship between overstory/understory LAI and overstory crown fraction. The model captures various features of layers of foliage growth, including the “understory seasonal dip effect.” In terms of practical aspects, we generated time series of the moderate resolution imaging spectroradiometer (MODIS)-layered LAI product for 2001–2020 at the spatial resolution of 230 m over Russian forests. We calculated the mean layered LAI of species and contrasted with typical values from the literature surveys. According to our estimates, the relative contribution of understory LAI increases from South to North—28% of forest pixels have understory LAI, which exceeds that of overstory, and those pixels are located in the northern part of the eastern Siberia and occupied by larch forests. The layered LAI product was intercompared/validated with multiple ground and remote sensing data.

A pilot post-mortem study identifies a strong correlation between the attenuation coefficient estimated from the OCT data and some morphological features of the sample, namely the number of nuclei in the field of view of the histological image and the fiber structural parameter introduced in the study to quantify the difference in the myelinated fibers arrangements. The morphological features were identified from the histopathological images of the sample taken from the same locations as the OCT images and stained with the immunohistochemical (IHC) staining specific to the myelin. It was shown that the linear regression of the IHC quantitative characteristics allows adequate prediction of the attenuation coefficient of the sample. This discovery opens the opportunity for the usage of the OCT as a neuronavigation tool.

Abstract: This research offers a method of estimating human biological age based on the spectral analysis of the bioelectric activity of the brain for the first time. We have developed an IDC decentralization index, which is calculated by taking the total reduction of the background neurotrophic influences of the brain activating system on the peripheral tissues and organs into account. The obtained dependence of the IDC index on the age of healthy people at ages of 10 to 90, as well as on the degree of differentiation G1–G4 of cancer cells, was close to linear. The accumulation of cell malfunctions and mutations with age could be detected by the growth in the IDC index from 100 to 900 units. An even greater number of cell mutations in cancer patients with the G1 to G4 degree of cell differentiation resulted in the IDC index increasing to 3000 units or more. These data allowed us to estimate a person’s biological age after a 10-minute registration of the bioelectric activity of the brain. The estimation accuracy increased when averaged data were obtained for several trials of each subject. The technology is applicable in scientific research in the field of gerontology, monitoring healthy people, revealing risk groups, and controlling treatment process in cancer patients.

The combination of immunomodulators and antibiotics in the treatment of animals with diseases of bacterial etiology is one of the effective strategies for animal therapy. The drug gentabiferon-B combines antibiotic gentamicin and species-specific (bovine) recombinant interferons -α and -γ. The study aimed to evaluate the effect of course application of gentabiferon-B on the cytogenetic stability of bone marrow cells of outbred mice after administering mitomycin C (MMC). The proportion of polychromatophilic erythrocytes in the bone marrow was assessed. There was no effect of gentabiferon-B on the frequency of polychromatophilic erythrocytes with micronuclei in both healthy animals and mice with MMC-induced cytogenetic instability. The course application of gentabiferon-B before the administration of MMC led to an increase in the proportion of polychromatophilic erythrocytes (46.03±2.61%) which was non-significantly different than the negative control group. The administration of MMC alone caused a decrease in the proportion of polychromatophilic erythrocytes to 33.33±1.83%. The antitoxic effect of gentabiferon-B led to an increase in the level of polychromatophilic erythrocytes by 38.1% compared to the group that received only MMC. Studies have shown that gentabiferon-B does not have mutagenic activity and anticlastogenic properties, however, it reduces the toxic effect of MMC. In conclusion, it is indicative that gentabiferon-B has antitoxic properties and can be safely used in animal therapy.

The anodic behaviour of pre-oxidised and non-oxidised Cu−Al-based anodes (Cu−10Al and Cu−9.8Al−2Mn) in KF−AlF3−Al2O3melts was studied through galvanostatic and potentiodynamic polarization techniques. The alloy compositions were oxidised for a short-term (8 h) at 700 °C, followed by galvanostatic polarization for 1 h at 800 °C with an applied current density of 0.4 A/cm2. The potentiodynamic curves were recorded with a sweep rate of 0.01 V/s. XRD analysis was conducted on frozen melt samples collected on the surface of the anode, and SEM observation was performed on the anode after the experiment to study the phases of the scales formed on the alloys. All the anode materials had a steady potential between 2.30 and 2.50 V(vs Al/AlF3). The corrosion rates of the anodes were calculated from the data acquired through potentiodynamic polarization. It was seen that pre-oxidised anodes possess a low corrosion rate compared to those without pre-oxidation treatment.

The propagation of light through a hybrid-aligned nematic layer with a surface disclination line is investigated in a pulsed magnetic field. The experimental dependences of light intensity I on time t accompanied by interference oscillations are presented. The shift and expansion of the interference extrema as functions of the magnetic field pulse length during the reaction are shown. The I(t) dependence for the relaxation process is calculated with allowance for scattering. The calculated I(t) dependence agrees well with the experimental dependence over the entire hybrid-aligned nematic layer, except for the surface layer.

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We report on a model of an organic solar cell in which a photosensitive layer doped with plasmon nanoparticles acts as not only an absorbing element but also a mirror involved in the formation of the Tamm plasmon polariton. It is shown that such solar cells can be fabricated without metal contacts, thus avoiding undesired losses in the system. Methods for an additional increase in the integral absorption by applying metal or dielectric mirrors to the lower boundary of the photonic crystal are proposed. It has been found that the integral absorption in the active layer can be increased by 15% compared to classical optimized planar solar cells.

This paper deals with list colorings of uniform hypergraphs. Let H(m, r, k) be the complete r-partite k-uniform hypergraph with parts of equal size min which each edge contains exactly one vertex from some k≤ rparts. Using results on multiple covers by independent sets, we establish that, for fixed kand r, the list-chromatic number of H(m, r, k) is (1 + o(1)) logr/(r−k+1)(m) as m→ ∞.

Nosocomial pneumonia and nosocomial tracheobronchitis present a significant problem of anesthesiology and critical care medicine. This review presents the results of our own research on the usefulness of new molecular biomarkers in the early diagnosis of nosocomial pneumonia, as well as modern principles for its prevention. A promising direction for the early diagnosis of nosocomial pneumonia and its complications is the study of new molecular biomarkers, in particular, Club cell protein and surfactant proteins. Effective prevention of nosocomial pneumonia should be based on a complex of modern evidence-based methods.

The interference of nonpolarized light transmitted through an ensemble of nematic liquid crystal domains formed on a polycarbonate surface has been investigated. A model based on the superposition of the ordinary and extraordinary beams passing through domains with a radial structure has been developed. Expressions for the phase difference and intensity of the interfering beams have been derived that take into account the distribution of the liquid crystal director field. The dependences of the optical transmittance of a domain layer on the applied voltage have been calculated with regard to the material and optical constants of a liquid crystal and structural features and averaged morphological parameters of individual domains in the experimental sample. The results of the calculation are consistent with the experimental data, which confirms the validity of the proposed model.

The specific heat, thermal expansion, permittivity, and electrocaloric effect in bulk of BaTiO3(BT) samples in the form of nano- (nBT-500 nm) and micro- (mBT-1200 nm) ceramics fabricated using spark plasma sintering and solid-state plasma techniques have been investigated. The size effect has been reflected, to a great extent, in the suppression of the specific heat and thermal expansion anomalies and in the changes in the temperatures and entropies of phase transitions and permittivity, and a decrease in the maximum intensive electrocaloric effect: $$\Delta T_{{{\text{AD}}}}^{{\max }}$$= 29 mK (E= 2.0 kV/cm) for nBT and $$\Delta T_{{{\text{AD}}}}^{{\max }}$$= 70 mK (E= 2.5 kV/cm) for mBT. The conductivity growth at temperatures above 360 K leads to the significant irreversible heating of the samples due to the Joule heat release in the applied electric field, which dominates over the electrocaloric effect.

A new type of electrical discharge was discovered in Gatchina, which produces long-lived luminous formations with the same unique physical properties as natural ball lightning. This paper reviews the research work on the Gatchina discharge that has been done by a number of independent groups and which has provided important insights into the nature of both the discharge and ball lightning formation processes. However, the luminous formations that appeared in the experiments by these groups have a shorter lifetime than objects created by the authors of the proposed method and fail to exhibit some of the specific properties of ball lightning. In this paper, the basic parameters and operation regimes of a facility for creating such formations are discussed; their optimization will eliminate these drawbacks. The review discusses the properties of both the discharge and the luminous objects formed in it, which were observed by the present authors and which other groups failed to reproduce. A model of natural ball lightning is proposed, in the framework of which the peculiar properties of the Gatchina discharge and of the long-lived luminous formations observed in it are explained. The experimental facility developed exhibits a number of features that allow the near-100%-effective production of long-lived luminous formations, thus enabling their physical characteristics to be studied, in principle, on a systematic basis.

The effect of thermal cycling and sintering temperature on the chemical and thermodynamic stability of the bulk multiferroic xLa0.7Pb0.3MnO3–(1 – x)PbTiO3quasi-ceramic and ceramic composites has been experimentally investigated. It is shown that the limiting temperature of the long-term sample firing should not exceed 1070 K. It has been found that sintering at this temperature and/or short-term exposure of the samples at higher temperatures (up to 1220 K) significantly increase the sample compactness, stabilize the thermal expansion, and enhance the quality of the composites. It has been established that the component grain integrity is violated by shrinkage of the samples and a sharp change in their volume during the phase transition of a ferroelectric component.

Extremal problems on the number of j-independent sets in uniform simple hypergraphs are studied. Nearly optimal results on the maximum number of independent sets for the class of simple regular hypergraphs and on the minimum number of independent sets for the class of simple hypergraphs with given average degree of vertices are obtained.

A method for determining and correcting distortions in spectral-domain optical coherence tomography images caused by medium dispersion was developed. The method is based on analysis of the phase distribution of the interference signal recorded by an optical coherence tomography device using an iterative approach to find and compensate for the effect of a medium’s chromatic dispersion on point-spread function broadening in optical coherence tomography. This enables compensation of the impact of medium dispersion to an accuracy of a fraction of a radian (units of percent) while avoiding additional measurements and solution of the optimization problem. The robustness of the method was demonstrated experimentally using model and biological objects.

Lung cancer during pregnancy is a rare condition associated with a poor prognosis. Gestational lung malignancy can rarely be associated with placental and fetal metastases, associated with potentially poor maternal and pediatric outcomes. Here, we present the case of a 34-year-old nulliparous woman at 37 weeks of gestation, presenting with non-small-cell Lung cancer with metastatic spread to the placenta. In addition, we report an updated review of the literature on all cases of placental metastatic lung cancer.

The kinetic data indicate that the addition of tertiary phosphines to α-methylene lactones in acetic acid is strongly accelerated in comparison to the reactions of related open-chain esters. Six-membered α-methylene-δ-valerolactone exhibited a more pronounced rate increase than five-membered α-methylene-γ-butyrolactone. The use of α-methylene-γ-butyrolactam as a nitrogen analogue of α-methylene-γ-butyrolactone resulted in a total loss of the reaction acceleration. The observed reactivities were rationalized by DFT calculations at the RwB97XD/6-31+G(d,p) level of theory, showing that the intramolecular interaction between phosphonium and enolate oxygen centers provided by the locked s-cis-geometry of the heterocycles plays an important role in the stabilization of intermediate zwitterions. The reactivity is also controlled by the conformational flexibility of the heterocycle. The geometries of five-membered and, especially, six-membered lactone cycles are slightly changed upon the nucleophilic attack of phosphine, leading to the stabilizing stereoelectronic effect by the Ρ···Ο interaction. The addition of phosphine to α-methylene-γ-butyrolactam significantly distorts the initial geometry of the heterocycle, making the nucleophilic attack unfavorable. The application of the stereoelectronic effect to enhance the efficiency of the phosphine-catalyzed Michael and Pudovik reactions of α-methylene lactones was demonstrated.

Structural or crystal asymmetry is a necessary condition for the emergence of zero-bias photocurrent in light detectors. Structural asymmetry has been typically achieved via p–n doping, which is a technologically complex process. Here, we propose an alternative approach to achieve zero-bias photocurrent in two-dimensional (2D) material flakes exploiting the geometrical nonequivalence of source and drain contacts. As a prototypical example, we equip a square-shaped flake of PdSe2with mutually orthogonal metal leads. Upon uniform illumination with linearly polarized light, the device demonstrates nonzero photocurrent which flips its sign upon 90° polarization rotation. The origin of zero-bias photocurrent lies in a polarization-dependent lightning-rod effect. It enhances the electromagnetic field at one contact from the orthogonal pair and selectively activates the internal photoeffect at the respective metal-PdSe2Schottky junction. The proposed technology of contact engineering is independent of a particular light-detection mechanism and can be extended to arbitrary 2D materials.