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Background: There is paucity of data in the available medical literature regarding the parameters of the volumetric perfusion of pancreas grafts. Methods: From 5 February 2016 to 23 December 2021, we performed perfusion computed tomography in 41 patients at different times after simultaneous pancreas and kidney transplantation. The study group consisted of 18 men (44%) and 23 women (56%) with a long history of type 1 diabetes mellitus complicated by terminal chronic renal failure. The results of the perfusion computed tomography of the pancreas graft were studied, and the effects of post-transplantation timing and graft revascularization peculiarities on volumetric perfusion parameters were evaluated. Results: The median arterial blood flow, arterial blood volume, and permeability of the pancreas graft were 115.1 [99.7;130.3] mL/100 mL/min, 46.7 [37.4;56.9] mL/min, and 8.6 [4.1;11.4] mL/100 mL/min, respectively. No statistically significant differences in the averaged perfusion values were found in the head, body, and tail of the pancreas graft. The post-transplantation timing and the number of arteries involved in graft revascularization did not have a significant effect on the volumetric perfusion of the graft. Conclusion: The volumetric perfusion results of the pancreas graft correspond to those obtained in the study of pancreatic perfusion in healthy participants. [ABSTRACT FROM AUTHOR]

The current intensive development of steelmaking is being impeded by a scarcity of pure scrap. The potential to replace pure scrap with metallized raw materials that are naturally alloyed with vanadium and titanium, such as annealed unfluxed titanomagnetite pellets, could facilitate the achievement of key objectives in metallurgical development, particularly in the smelting of electric steel. The objective of this research was to produce annealed and metallized pellets from titanomagnetite concentrate under laboratory conditions, with the intention of further processing them as a commercial product in a blast furnace or as an intermediate product for the production of hot briquetted iron (HBI). The results demonstrate that pellets derived from titanomagnetite concentrate exhibit sufficient compressive strength (up to 300 kg/pellet) and a degree of metallization exceeding 90%, which aligns with the requirements for electric steelmaking. The suitability of pellets derived from titanomagnetite concentrate for use in both blast furnaces and metallization processes has been corroborated. [ABSTRACT FROM AUTHOR]

The mass transfer (diffusion) properties of a colloidal capillary-porous material (pears cut into plates 5 mm thick for convective drying) as a function of the moisture content of the material at different temperatures of the drying agent (air) were studied experimentally. Since the pear sample shrinks significantly during drying, the change in sample thickness during the process was taken into account when calculating the mass conductivity coefficient. At the same time, the linear shrinkage of the specified material was studied. The dependences of the mass conductivity coefficient on the moisture content of the material k = f(u) were obtained from drying curves based on the zonal method at a constant temperature of the drying agent tdr. They represent dependences concave to the abscissa axis that increase with moisture content, which is typical of dried materials. The minimum values of the mass conductivity coefficient on the graphs k = f(u) vary from 0.3∙10–10 m2/s at 30°C to 2.2∙10–10 m2/s at 60°C. With a change in the moisture content of the material, the mass conductivity coefficient changes multiply. The shrinkage data for engineering calculations was described by equation. The possibility of describing the temperature dependence of the mass conductivity coefficient (moisture diffusion) by Arrhenius equation is shown. The values of the Arrhenius equation parameters are obtained. [ABSTRACT FROM AUTHOR]

A molecular dynamics model of a five-component coating based on the TiAlTaSiN system is proposed. A superposition of interatomic potentials is chosen to describe the interaction between the atoms of the system. The superposition includes both the available interatomic potentials and those calculated on the basis of the electron density functional theory. A molecular dynamics simulation is used to analyze the resistance of the developed coating model to thermal and mechanical loading. The influence of the concentration of alloying inclusions and the crystallographic orientation of the grains of this multi-component coating with respect to the applied load on its strength and deformation properties is investigated. A qualitative agreement between the simulation results and the experimental data is demonstrated. [ABSTRACT FROM AUTHOR]

Molecular dynamics (MD) is a powerful tool for modeling the phase and structural transformations and the evolution of defects and their influence on the metallic material properties. The accuracy of MD modeling directly depends on the quality of interatomic potentials. Modern machine-learning potentials are typically trained on random atomic configurations. This approach has significantly improved the quality of new potentials over traditional EAM potentials. In this work, exact solutions to the equations of atomic motion are offered to train the machine learning potentials. [ABSTRACT FROM AUTHOR]

The development of methods to detect plant stress is not only a scientific challenge, but is also of great importance for agriculture and forestry. However, at present, stress diagnostics based on plant spectral characteristics has several limitations: (1) the high dependence of stress assessment on plant species identity; (2) the poor differentiation of different types of stress; and (3) the difficulty of detecting stress before visible symptoms appear. In this regard, the development of plant spectral metrics represents a significant area of research. Ficus elastica plants were exposed under the photosynthetic photon flux density (PPFD) from 0 to 1200 μmol photons m−2s−1. Exposure of F. elastica leaves to excess light (EL) (≥400 μmol photons m−2s−1) resulted in an increase in reflectance in the yellow-green region (522–594 nm) and a decrease in reflectance in the red region (666–682 nm) of the spectrum, accompanied by a shift of the red edge point toward the longer wavelength. These changes were revealed using the previously proposed light stress index (LSI = mean(R666:682)/mean(R522:594)). Based on the results obtained, two new vegetation indices (VIs) were proposed: LSIRed = R674/R654 and LSINorm = (R674 − R654)/(R674 + R654), indicating light stress by changes in the red region of the spectrum. The results of the study showed that LSI, LSIRed, and LSINorm have a high degree of coupling strength with maximal quantum yields of photosystem II values. The plant response to EL exposure, as assessed by the values of these three VIs, was well expressed regardless of the PPFD levels. The effect of EL at non-stressful PPFDs (50–200 μmol photons m−2s−1) was found to disappear within one hour after cessation of exposure. In contrast, the effect of the stressful PPFD (800 μmol photons m−2s−1) was found to persist for at least 80 h after cessation of exposure. The results of the study indicate the need to consider light history in spectral monitoring of vegetation. [ABSTRACT FROM AUTHOR]

In this work, efficient and environmentally friendly electrocatalysts based on 2D nanocrystals of graphitic carbon nitride (g-C3N4) decorated with praseodymium orthoferrite (PrFeO3) nanoparticles were designed and synthesized for the efficient electrocatalytic treatment of pharmaceutical wastewater. Nanocrystalline g-C3N4 was obtained through the thermal polymerization of urea in air. Self-propagating high-temperature synthesis (SHS) was employed for producing PrFeO3. Subsequently, the nanopowders underwent ethanol-assisted mechanochemical treatment using a planetary ball mill. As a result, a series of samples was obtained with the PrFeO3 content ranging from 0 to 100 wt%. The resulting nanocomposites were dispersed in a solution of isopropyl alcohol with the addition of 0.5% Nafion; thereafter, the suspensions were applied to an ITO glass substrate to form electroactive thin films. The series underwent analysis using an X-ray diffraction, scanning electron microscopy, surface area and porosity analysis, cyclic voltammetry, and electrochemical impedance spectroscopy. The influence of the g-C3N4 to PrFeO3 ratio on the electrochemical activity during the decomposition of tetracycline hydrochloride was analyzed. Consequently, an optimal ratio was determined, leading to the rapid and complete decomposition of the antibiotic in a neutral aqueous environment. In conclusion, it should be noted that the process of electrocatalytic decomposition of tetracycline hydrochloride has been comprehensively studied. [ABSTRACT FROM AUTHOR]

We suggest a new method of localization of partial discharges in high-power electrical systems. Ozone in a hydrogenerator is produced by chemical reactions induced by partial discharges in the stator region. The transport of ozone in an operating hydrogenerator is analyzed using a computational fluid dynamics model. The main aim of this work is to evaluate the ozone distribution in the generator radiators. Ozone sources are introduced into the stator model in different positions to analyze their effect on the measured values at the sensing points of radiators. Our results demonstrate a possibility of localization of partial discharges in hydrogenerator stator bars by ozone emission. [ABSTRACT FROM AUTHOR]

To understand the mechanism of changes in the c-wave of the electroretinogram (ERG) in diabetic rats, and to explore how glucose manipulations affect the c-wave. Vitreal ERGs were recorded in control and diabetic Long-Evans rats, 3–60 weeks after IP vehicle or streptozotocin. A few experiments were performed on Brown Norway rats. Voltage responses to current pulses were used to measure the transepithelial resistance of the retinal pigment epithelium (RPE). During development of diabetes the b-wave amplitude progressively decreased to about half of the initial amplitude after a year. In contrast, the c-wave was strongly affected from the very beginning (3 weeks) of diabetes. In control rats, the c-wave was cornea-positive at lower illuminations but was cornea-negative at higher (photopic) illumination. In diabetics, the whole amplitude-intensity curve was shifted toward negativity. The magnitude of this shift was markedly affected by acute glucose manipulations in diabetics but not in controls. Increased blood glucose made the c-wave more negative, and decreased blood glucose with insulin had the opposite effect. Experimentally induced acidification of the retina had a small effect that was different from diabetes, shifting the c-wave toward positivity, slightly in controls and more noticeably in diabetics. One reason for the significant negativity of the diabetic ERG was a decrease of the cornea-positive response of the RPE due to a decrease of the transepithelial resistance. The ERG c-wave is more negative in diabetics than in control animals, and is far more sensitive to changes in blood glucose. The increased negativity is largely if not entirely due to changes in the transepithelial resistance of the RPE, an electrical analog of the breakdown of the blood-retinal barrier observed in other studies. The sensitivity of the c-wave to glucose in diabetics may also be due to changes in transepithelial resistance. [ABSTRACT FROM AUTHOR]

The hydrocarbon temperature–time curve is widely used instead of the standard curve to describe the temperature in the environment of structural surfaces exposed to fire in oil and gas chemical facilities and tunnels. This paper presents calculations of the ratio of time to reach critical temperatures at different nominal fire curves for steel structures such as bulkheads and columns with different types of fireproofing. The thermophysical properties of the fireproofing materials were obtained by solving the inverse heat conduction problem using computer simulation. It was found that the time interval for reaching critical temperatures in structures with different types of fireproofing in a hydrocarbon fire decreased, on average, by a factor of 1.2–1.7 compared to the results of standard fire tests. For example, for decks and bulkheads with mineral wool fireproofing, the K-factor of the ratio of the time for reaching the critical temperature of steel under the standard curve to the hydrocarbon curve was 1.30–1.62; for plaster, it was 1.56; for cement boards, it was 1.34; for non-combustible coatings, it was 1.38–2.0; and, for epoxy paints, it was 1.71. The recommended values of the K-factor for fire resistance up to 180 min (incl.) were 1.7 and, after 180 min, 1.2. The obtained dependencies would allow fireproofing manufacturers to predict the insulation thickness for expensive hydrocarbon fire experiments if the results of fire tests under standard (cellulosic) conditions are known. [ABSTRACT FROM AUTHOR]

The potential for amplifying tunnel magnetoresistance and magnetoimpedance in island nanofilms without energy consumption or the use of amplifying devices was studied. Such amplification was observed for the films deposited on a Gd2O3 layer instead of a glass substrate. The enhancement is due to the f–d exchange interaction established between atoms with unfilled f- and d-electron shells, present in both Fe and Gd2O3. The f–d exchange interaction enhances the ordering of the magnetic structure within the Fe ferromagnetic layer, increases its magnetization, and subsequently improves the properties that depend on this magnetization. Iron and Gd2O3 were selected because the magnetic moments of Fe in the iron group and Gd in the lanthanide series are among the highest effective ones: μFe = 7.13 μB and μGd = 7.95 μB. This, according to theory, determines the high energy of the f–d exchange interaction. The island morphology of Fe films deposited on a Gd2O3 layer enabled electron tunneling under the influence of the f–d exchange interaction. This allowed the study of tunnel magnetoresistance under direct current and magnetoimpedance under alternating current influenced by the f–d exchange interaction. The frequency dependence of the active component Z', the reactive component Z'', and the total impedance Z of Fe films on glass and Gd2O3 substrates, without and under a constant magnetic field of 7500 Oe, was analyzed. These characteristics are used to determine the frequency dependence of tunnel magnetoimpedance and estimate tunnel magnetoresistance for Fe island films on glass and Gd2O3 substrates. These characteristics were found to be 55 % higher, on average, for Fe deposited on Gd2O3 than for Fe on glass, both at a low frequency of 0.1 Hz for tunnel magnetoresistance and at higher frequencies of 1–105 Hz for tunnel magnetoimpedance. This results from the influence of f–d exchange interaction on electron tunneling between the iron islands. [ABSTRACT FROM AUTHOR]

Eigenmodes in equilateral and isosceles triangular trimers of infinite cylinders have been studied using the theory of multiwave scattering. Equations have been derived for the eigenfrequencies of the exceptional points where eigenfrequencies and eigenvectors are degenerate. The symmetry of the isosceles triangular trimer determines the separation of modes antisymmetric in the base direction. In the case of the equilateral triangular trimer, modes are separated into symmetric and double degenerate rotational modes. It has been found that damping symmetric modes in the trimer have a higher Q-factor compared to a dimer, which is of significant importance for applications of effects based on exceptional points. The behavior of complex eigenfrequencies in the isosceles triangular trimer has also been studied depending on the ratio of the lengths of its base and leg. At the point corresponding to the equilateral triangular trimer, the Q-factors of symmetric and antisymmetric modes have the local maximum and minimum, respectively. [ABSTRACT FROM AUTHOR]

3-Aroylpyrrolo[2,1-c][1,4]benzoxazine-1,2,4-triones reacted with 6-amino-1,3-dimethylpyrimidine-2,4(1H,3H)-diones to give 3-aroyl-4-hydroxy-1-(2-hydroxyaryl)-1′,3′-dimethylspiro[pyrrole-2,5′-pyrrolo-[2,3-d]pyrimidine]-2′,4′,5,6′(1H,1′H,3′H,7′H)-tetraones. The product structure was confirmed by X-ray analysis. The described reaction provides a simple route to the difficultly accessible spiro[pyrrole-2,5′-pyrrolo[2,3-d]-pyrimidine] heterocyclic system. [ABSTRACT FROM AUTHOR]

Abstrasc: A method is proposed for reconstructing the acoustic parameters of a medium by iterative processing of the coherence matrices of the acoustic field of random sources, for some of which their power density is known. The possibilities of increasing the stability and accelerating the convergence of the method are discussed. The reconstruction results are compared with the functional-analytical approach based on the processing of the scattering amplitude. [ABSTRACT FROM AUTHOR]

Geosynchronous magnetopause crossings (GMCs) were analyzed during geomagnetic storms on February 26, March 23, and April 23, 2023. GMC-associated magnetosheath intervals were identified using magnetic data acquired from the GOES-16 and GOES-17 spacecraft. A comparative analysis of various magnetopause models was performed on the base of solar wind conditions measured by the THEMIS-E spacecraft and the Wind interplanetary monitor. The analysis of models was based on statistical parameters for determining magnetosheath intervals. It was shown that for all three storms, the model presented in [1] demonstrated the best accuracy. For events of moderate magnetic storms against the background of small negative Bz component of the interplanetary magnetic field (IMF), good results are obtained with the model described in [2]. For extreme events with very high solar wind pressures and/or very strong negative IMF Bz, the model shown in [3] exhibits good accuracy, and satisfactory accuracy is also demonstrated by models presented in [4, 5]. It was shown that the accuracy of the models was affected by the following factors and effects: the choice of interplanetary monitor, the dependence of the model on the solar wind pressure, the Bz saturation effect, the dawn–dusk magnetopause asymmetry, and the effect of prehistory. [ABSTRACT FROM AUTHOR]

5-Aryl-1H-pyrrole-2,3-diones reacted with amidoximes to give enamines containing a 1,2,4-oxadi-azole fragment that are potential precursors to novel 1H-pyrrole-2,3-diones. The described reaction is the first example of recyclization of 4-unsubstitued 5-aryl-1H-pyrrole-2,3-diones by the action of 1,4-binucleophiles. [ABSTRACT FROM AUTHOR]

We characterize the absolutely Calderón elements of the canonical pair of sequence spaces in terms of the Peetre -functional. This result has been known to the first author since rather long ago but the proof appears here. Also, we formulate a few unsolved problems. [ABSTRACT FROM AUTHOR]

Non-steroidal anti-inflammatory drugs (NSAIDs) are an important class of medications; however, they have some drawbacks. We are developing a new NSAID with pronounced anti-inflammatory and analgesic activities and a very low toxicity—(Z)-3-(2-oxo-2-(p-tolyl)ethylidene)piperazin-2-one (piron). In this work, we describe the synthesis of the main metabolite of piron—(Z)-4-(2-(3-oxopiperazin-2-ylidene)acetyl)benzoic acid. The anti-inflammatory activity of the synthesized metabolite was determined in vivo. [ABSTRACT FROM AUTHOR]

The reaction of 4-(4-bromophenyl)-2,4-dioxobutanoic acid with thiosemicarbazide, in a ratio of 1:2, when boiled in ethanol gives 3-(4-bromophenyl)-1-carbamothioyl-5-(2-carbamothioylhydrazinyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid with a good yield. This compound was fully characterized. [ABSTRACT FROM AUTHOR]

In this research endeavor, we report the successful synthesis of mesoporous and single-phase nanopowders of orthorhombic hafnium titanate, HfTiO 4 , using a facile solution combustion approach. The direct synthesis yielded an X-ray amorphous product, which was found to crystallize completely into single-phase HfTiO 4 upon annealing at 800 °C for 1 h, marking the first successful synthesis of this material via this method. The synthesized HfTiO 4 nanopowders were thoroughly characterized using various techniques. Structural analyses conducted through powder X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy confirmed the formation of pure orthorhombic HfTiO 4 nanocrystals, exhibiting an average size of 24.6 nm. Moreover, the scanning electron microscopy (SEM) morphological study and adsorption-structural analysis of the HfTiO 4 nanopowder revealed a well-developed mesoporous structure with a specific surface area of 17 m2/g and an average pore size of 15 nm. The band gap of the synthesized HfTiO 4 was determined to be 3.47 eV, designating it as a potential photoanode material. Photocatalytic applications were evaluated through photoelectrochemical tests, which showcased a high photoresponse in both the UV (365 nm) and visible (450 nm) regions of the spectrum. Importantly, the photoresponse under visible light surpassed that of commercial TiO 2 (Sigma-Aldrich), signifying its potential as an efficient photoanode material. [Display omitted] [ABSTRACT FROM AUTHOR]

Cellular stress is an intrinsic part of cell physiology that underlines cell survival or death. The ability of mammalian cells to regulate global protein synthesis (aka translational control) represents a critical, yet underappreciated, layer of regulation during the stress response. Various cellular stress response pathways monitor conditions of cell growth and subsequently reshape the cellular translatome to optimize translational outputs. On the molecular level, such translational reprogramming involves an intricate network of interactions between translation machinery, RNA-binding proteins, mRNAs, and non-protein coding RNAs. In this review, we will discuss molecular mechanisms, signaling pathways, and targets of translational control that contribute to cellular adaptation to stress and to cell survival or death. [ABSTRACT FROM AUTHOR]

The internal quantum efficiency of GaAs/AlGaAs- and InGaAs/AlGaAs-heterostructures for infrared light emitter diodes has been determined. The influence of the growth conditions of heterostructures grown by the molecular beam epitaxy and post-growth annealing on the quantum efficiency of heterostructures has been investigated. It has been shown that it is possible to increase the quantum luminescence efficiency of the studied heterostructures up to 75–80% at the average power by the combined optimization of these processes. [ABSTRACT FROM AUTHOR]

The possibilities of the luminescence method for studying Si–oxide and Si–SiO2–oxide structures have been demonstrated. A model of the electronic structure of Ta2O5 and TiO2 layers is proposed, which explains the shape of the spectral luminescence distribution independent of the excitation way. A comparison of the luminescence spectra of single oxide layers with the spectrum of Si–SiO2–oxide structures made it possible to draw conclusions about the interaction between layers during layered structure formation and estimate the band gap: 4.4 and 3.3 eV for Ta2O5 and TiO2, respectively. The formation of Ta2O5 on the SiO2 surface led to transformation in the SiO2 surface region, manifesting itself in weakening of the luminescence band at 1.9 eV and formation of defects (luminescence centers) in the vicinity of 3 eV. Synthesis of TiO2 on the surface of SiO2 was not accompanied by any changes in the luminescence spectra. [ABSTRACT FROM AUTHOR]

Titanium and zirconium alloys are indispensable structural materials in many technical applications due to their unique mechanical and physicochemical properties. Titanium and zirconium belong to the fourth ("titanium") group, due to which one would expect them to exhibit a similar character of hydrogen permeability through alloys of these metals. The results of experiments on the hydrogen permeability of these alloys are compared and analyzed. It is revealed that the hydrogen permeation kinetics for both alloys is mainly determined by the low rate of surface processes and phase transformations, occurring as a result of increasing hydrogen concentration. It is shown that the hydrogen permeability method can be used to find the terminal solid solubility of hydrogen in metals. [ABSTRACT FROM AUTHOR]

The method of fabrication of solid solution powder of uranium/plutonium (38%) oxides from the pulp of ammonium uranyl-plutonyl carbonate process (AUPuC) by microwave radiation in reducing and atmospheric environments was proposed and tested at the laboratory level. For research the pulp was prepared, obtained by co-precipitation of uranium and plutonium from nitrate solution (simulator for stripping product). The process consists of three main stages: oxidation of Pu(IV) to Pu(VI), precipitation, and conversion in a laboratory microwave unit. According to data of the X-ray diffraction analysis the powders synthesized in a reducing atmosphere and an atmospheric environment are a solid cubic solution (UxPu1–x)O2 and (PuO2, U3O8) mixed oxide, respectively. Scanning electron microscopy and electron probe microanalysis of the powder obtained in an atmospheric environment showed a fairly uniform distribution of U, Pu, and O in the solid phase. [ABSTRACT FROM AUTHOR]

The interaction of NiO clusters with a graphene layer of a nanotube in NiOx/CNT composites is simulated based on a theoretical analysis of Ni K-edge XANES spectra. Various cases of orientation of crystallographic planes relative to the nanotube wall are considered. It was determined that Ni in the composite is predominantly in the 2+ state, NiO particles are oriented towards the tube wall by the (200) plane. Accounting for carbon atoms even in the first sphere of the nickel environment makes it possible to achieve good agreement between the theoretical spectrum and experiment. [ABSTRACT FROM AUTHOR]

The results of experimental studies of the hydrodynamics of a coolant in the outlet section of a cassette fuel assembly of the RITM reactor of a low-power nuclear power plant are presented. The purpose of the work was to study the redistribution of axial velocity and coolant flow rate at the outlet of the fuel rod bundle, behind the fuel assembly cap, near the coolant extraction pipe, and in the holes of the upper support plate. To achieve the goal, experiments were carried out on a research stand with an air working medium on a model of the outlet section of the fuel assembly, including the outlet fragment of the fuel rod bundle, the cap, the upper support plate with the coolant extraction pipe. When conducting research, the pneumometric method and the method of injection of a contrast impurity were used. An area covering the entire cross section of the model was chosen as the study area. The picture of the coolant flow is represented by cartograms of the distribution of axial velocity and coolant flow rate, as well as cartograms of the distribution of the contrast impurity. The experimental results can be used in the design of new active sections of RITM reactors. The resulting experimental base can be used for local validation of CFD programs and onedimensional thermal-hydraulic codes used to substantiate the thermal reliability of cores. [ABSTRACT FROM AUTHOR]

The reaction of 3-aroylpyrrolo[1,2-a][4,1]benzoxazepine-1,2,4-triones with 3-(cyclohexylamino)-5,5-dimethylcyclohex-2-en-1-one afforded 3′-aroyl-1-cyclohexyl-4′-hydroxy-1′-[2-(hydroxymethyl)phenyl]-6,6-dimethyl-6,7-dihydrospiro[indole-3,2′-pyrrole]-2,4,5′(1H,1′H,5H)-triones. This reaction can be regarded as a new method of synthesis of spiro[indole-3,2′-pyrrole] derivatives. [ABSTRACT FROM AUTHOR]

An estimate of the processes of afforestation and forest restoration after fires is relevant for a significant territory of Russia, including due to the issue of carbon neutrality. In this paper we examine the possibilities of radar monitoring of the afforestation process based on the Cloude–Pottier decomposition of dual-polarization L-band data time series. Preliminary segmentation is performed based on the minimal radar backscatter values for the entire observation period. This makes it possible to separate into a separate class treeless areas and open forests, both those that existed before the beginning of the study and those that formed later. Next, polarimetric decomposition is performed by the Cloude–Pottier method to obtain parameters H (entropy) and α (scattering angle) and form time series from them. Research showed the fundamental possibility of monitoring forest dynamics on the H-α plane, where the points of the test plots form characteristic time tracks. A mature dense forest, the characteristics of which are assumed to be constant, was used as a reference for estimating the rate of change on the H-α plane. [ABSTRACT FROM AUTHOR]

Quantum measurements play a crucial role in the field of quantum computing and quantum information processing. However, these measurements are susceptible to errors, which can compromise the accuracy and reliability of the collected statistics. In this work, we address this challenge by leveraging a Fuzzy measurements mathematical model for quantum measurement error correction. Building upon previous work dedicated to the development of the fuzzy mathematical model, which was primarily focused on quantum tomography of ion qubits, we extend its applicability to correct statistics obtained from quantum measurements in general. Rather than analyzing the sources and characteristics of readout errors, we calculate the readout errors using preliminary measurements. By utilizing these calculated errors, we derive corrections that effectively mitigate these errors. We demonstrate the efficiency of our approach through numerical simulations. Our correction approach is applicable to quantum computing platforms that rely on statistical quantum measurements, providing a practical solution for improving the accuracy of quantum data analysis. This work builds upon previous research and contributes to the development of robust techniques for accurate statistical analysis in quantum systems. [ABSTRACT FROM AUTHOR]

In this paper, we study long-term changes in the main directions of movement (storm tracks) of extratropical cyclones in the North Atlantic over the period 1873–2021. It was found that in the cold half of the year (the period of the most intense cyclogenesis), the average latitudes of storm tracks in the longitudinal range from 60° to 10° W experience oscillations with periods ∼80–100, ∼40–47, and ∼22 years, indicating their possible association with solar activity variations. The trajectories of cyclones were shifted to the north at the minimum of the Gleissberg secular cycle (∼1900–1930) and to the south at the cycle maximum (∼1940–1960). The secular changes in storm track latitudes amount to ∼3°–5° in the western part of the North Atlantic (the area of formation and the most intensive development of cyclones). On the bidecadal scale, a northward shift of cyclone trajectories in even solar cycles and a southward shift in odd ones were found. The shift of cyclone trajectories to the north in even cycles reached maximal values (∼1°–2° relative to a secular variation) at the descending branch and the minimum of the solar cycle (2nd−6th years after the maximum) in the eastern part of the North Atlantic. Changes in intensity of the stratospheric polar vortex, caused by variations in galactic cosmic rays and geomagnetic activity, are a possible reason for oscillations in cyclone trajectories. [ABSTRACT FROM AUTHOR]

Auditory neuropathy spectrum disorder (ANSD) associated with mutations of the OTOF gene is one of the common types of sensorineural hearing loss of a hereditary nature. Due to its high genetic heterogeneity, ANSD is considered one of the most difficult hearing disorders to diagnose. The dataset from 270 known annotated single amino acid substitutions (SAV) related to ANSD was created. It was used to estimate the accuracy of pathogenicity prediction using the known (from dbNSFP4.4) method and a new one. The new method (ConStruct) for the creation of the protein-centric classification model is based on the use of Random Forest for the analysis of missense variants in exons of the OTOF gene. A system of predictor variables was developed based on the modern understanding of the structure and function of the otoferlin protein and reflecting the location of changes in the tertiary structure of the protein due to mutations in the OTOF gene. The conservation values of nucleotide substitutions in genomes of 100 vertebrates and 30 primates were also used as variables. The average prediction of balanced accuracy and the AUC value calculated by the 5-fold cross-validation procedure were 0.866 and 0.903, respectively. The model shows good results for interpreting data from the targeted sequencing of the OTOF gene and can be implemented as an auxiliary tool for the diagnosis of ANSD in the early stages of ontogenesis. The created model, together with the results of the pathogenicity prediction of SAVs via other known accurate methods, were used for the evaluation of a manually created set of 1302 VUS related to ANSD. Based on the analysis of predicted results, 16 SAVs were selected as the new most probable pathogenic variants. [ABSTRACT FROM AUTHOR]

The results of theoretical and experimental studies of impact ionization processes and charge carrier heating in multi-valley AIIIBV semiconductors at high electric field are presented and their relationship with the features of the band structure is discussed. A role of subsidiary L- and X-valleys, complex structure of the valence band and orientation dependence of the ionization coefficients are taken into account. A new approach to the choice of semiconductor materials with a large ratio of the ionization coefficients of holes and electrons to create the noiseless avalanche photodiodes due to monopolarity of hot charge carrier multiplication is proposed. [ABSTRACT FROM AUTHOR]

Hyperspectral imaging techniques are widely used to remotely assess the vegetation and physiological condition of plants. Usually, such studies are carried out without taking into account the light history of the objects (for example, direct sunlight or light scattered by clouds), including light-stress conditions (photoinhibition). In addition, strong photoinhibitory lighting itself can cause stress. Until now, it is unknown how light history influences the physiologically meaningful spectral indices of reflected light. In the present work, shifts in the spectral reflectance characteristics of Ficus elastica leaves caused by 10 h exposure to photoinhibitory white LED light, 200 μmol photons m−2 s−1 (light stress), and moderate natural light, 50 μmol photons m−2 s−1 (shade) are compared to dark-adapted plants. Measurements were performed with a Cubert UHD-185 hyperspectral camera in discrete spectral bands centred on wavelengths from 450 to 950 nm with a 4 nm step. It was shown that light stress leads to an increase in reflection in the range of 522–594 nm and a decrease in reflection at 666–682 nm. The physiological causes of the observed spectral shifts are discussed. Based on empirical data, the light-stress index (LSI) = mean(R666:682)/mean(R552:594) was calculated and tested. The data obtained suggest the possibility of identifying plant light stress using spectral sensors that remotely fix passive reflection with the need to take light history into account when analysing hyperspectral data. [ABSTRACT FROM AUTHOR]

Upon reaction with N-substituted pyrroloquinoxalinetriones, isatin hydrazone is oxidized to diazooxindole and enters into a formal [4+1] cycloaddition reaction with N-substituted pyrroloquinoxalinetriones to form compounds containing a spiro[dihydrofuran-2,3′-oxindole] fragment, which is interesting for medicinal chemistry. The reaction of diazooxindoles with N-unsubstituted pyrroloquinoxalinetriones afforded analogous substituted spiro[dihydrofuran-2,3′-oxindoles]. The resulting compounds show moderate antimicrobial activity. [ABSTRACT FROM AUTHOR]

In this paper, we study long-term changes in the main directions of movement (storm tracks) of extratropical cyclones in the North Atlantic over the period 1873–2021. It was found that in the cold half of the year (the period of the most intense cyclogenesis), the average latitudes of storm tracks in the longitudinal range from 60° to 10° W experience oscillations with periods ∼80–100, ∼40–47, and ∼22 years, indicating their possible association with solar activity variations. The trajectories of cyclones were shifted to the north at the minimum of the Gleissberg secular cycle (∼1900–1930) and to the south at the cycle maximum (∼1940–1960). The secular changes in storm track latitudes amount to ∼3°–5° in the western part of the North Atlantic (the area of formation and the most intensive development of cyclones). On the bidecadal scale, a northward shift of cyclone trajectories in even solar cycles and a southward shift in odd ones were found. The shift of cyclone trajectories to the north in even cycles reached maximal values (∼1°–2° relative to a secular variation) at the descending branch and the minimum of the solar cycle (2nd−6th years after the maximum) in the eastern part of the North Atlantic. Changes in intensity of the stratospheric polar vortex, caused by variations in galactic cosmic rays and geomagnetic activity, are a possible reason for oscillations in cyclone trajectories. [ABSTRACT FROM AUTHOR]

This work is devoted to the experimental study of evaporating droplets of titania-, silica-, and diamond-based nanofluids on a substrate under solar radiation. The influence of various factors, including the type of a material, concentration of nanocomponents, irradiation direction, droplet volume, and substrate material, on the droplet evaporation has been investigated. As a result, the critical concentrations of nanoparticles, at which the evaporation rate reaches a stable level, have been determined for droplets of the studied nanofluids. The regimes and stages of the droplet evaporation process have been analyzed for the cases of the subcritical and critical nanoparticle concentrations. The efficiency of droplet evaporation under solar radiation has been shown to strongly depend on radiation direction. The effects of droplet volume and substrate material on the evaporation rate have been studied. In addition to the evaporation efficiency, the morphology of the structures deposited from the droplets has been analyzed. It has been shown that these structures depend on the concentration and material of nanoparticles, as well as on the regime of droplet evaporation. The results of this study enable one to gain a deeper insight into the behavior of the droplets during evaporation under irradiation especially in the IR region and confirm the promise of application of nanofluids in the solar thermal energy systems. [ABSTRACT FROM AUTHOR]

Invasion of alien plant species entails great ecological, economic, and social consequences. One of the effective ways to manage invasive species may be to account for and destroy them using unmanned aerial vehicles. However, this requires learning to identify invasive species using real-time remote sensing. Recently, great hopes for solving this problem have been placed on hyperspectral cameras. In this regard, there is a need to fundamentally answer the question of the possibility of identifying plant species from spectral data, regardless of the time of data acquisition. The aim of the study was to identify four species of woody plants by the time series of spectral characteristics of their leaves, obtained using a hyperspectral camera. The study was conducted in laboratory conditions, in which the number of unaccounted for factors is much less than in the field. The objects of study were one native species Quercus robur L. and three species invasive for Europe – Fraxinus pennsylvanica Marsh., Ailanthus altissima (Mill.) Swingle, Parthenocissus inserta (A. Kern.) Fritsch. The collection of leaves for Hyperspectral Imaging (HSI) was carried out during the growing season of the plants at intervals of 7–10 days. Random Forest (RF) was chosen as the object classification method. The RF pixel-based test was carried out both for specific calendar dates (time slice) and for the time series when the RF model was trained on the data of one calendar date and tested on other calendar dates. None of the RF testing methods was able to classify all four species simultaneously with sufficient probability (more than 90%). Therefore, RF testing of combinations of two samples was used – "species" & "other three species" for all calendar dates. This approach made it possible to classify species by spectral characteristics of leaves with 100% reliability. It has been established that the spectral bands informative for RF pixel-based classification lie in the visible range of the spectrum in the range from 462 to 478, from 510 to 534, and from 566 to 646 nm. [ABSTRACT FROM AUTHOR]

The effect of heat treatment on the fatigue processes developing in tool steel 6KhS loaded by a "soft" scheme of cantilever bending of flat specimens is studied. The fatigue limit and the cyclic endurance are determined. The frequency characteristics and the dynamics of the frequency stability in tests of steel specimens at a load close to the fatigue limit are presented. The fatigue resistance of the steel after low-temperature tempering is shown to be highly scattered. The steel exhibits the highest frequency stability after high-temperature tempering. [ABSTRACT FROM AUTHOR]

A mathematical model of the process of deposition of solid particles on the outer surface of tubes of a finned heat exchanger on condensation of a vapor–gas mixture containing particles has been developed. The model is based on determining the temperature field in a round fin from a given distribution of sediment thickness. The proposed model makes it possible to evaluate the influence of design and thermal parameters on the heat flux removed by a round fin to a cylindrical tube. The influence of changes in such parameters as the fin thickness and thermal conductivity of the sediment layer on heat transfer was assessed. [ABSTRACT FROM AUTHOR]

The 1,3-dipolar cycloaddition of 1H-pyrrole-2,3-diones to azomethine ylides generated in situ by the condensation of L-proline and arylcarbaldehydes proceeds regio- and diastereoselectively to form substituted ethyl 1,2,5',6',7',7a'-hexahydro-3'H-spiro[pyrrole-3,2'-pyrrolo[2,1-b]oxazole]-4-carboxylates. The structure of the synthesized ethyl (3R*,3'R*,7a'S*)-3'-(4-bromophenyl)-2-oxo-1,5-diphenyl-1,2,5',6',7',7a'-hexahydro-3'H-spiro[pyrrole-3,2'-pyrrolo[2,1-b]oxazole]-4-carboxylate was confirmed by single crystal X-ray analysis. [ABSTRACT FROM AUTHOR]

The two main problems of dielectric metasurfaces for sensing and spectroscopy based on electromagnetic field enhancement are that resonances are mainly localized inside the resonator volume and that experimental Q-factors are very limited. To address these issues, a novel dielectric metasurface supporting delocalized modes based on quasi-bound states in the continuum (quasi-BICs) is proposed and theoretically demonstrated. The metasurface comprises a periodic array of silicon hollow nanocuboids patterned on a glass substrate. The resonances stem from the excitation of symmetry-protected quasi-BIC modes, which are accessed by perturbing the arrangement of the nanocuboid holes. Thanks to the variation of the unit cell with a cluster of four hollow nanocuboids, polarization-insensitive, delocalized modes with ultra-high Q-factor are produced. In addition, the demonstrated electric field enhancements are very high ( 10 3 – 10 4 ). This work opens new research avenues in optical sensing and advanced spectroscopy, e.g., surface-enhanced Raman spectroscopy. [ABSTRACT FROM AUTHOR]

Essential oils (EOs) are of commercial importance for medicine, food, cosmetics, the perfume industry, and agriculture. In plants, EOs, like the wax cover, serve as protection against abiotic stresses, such as high temperatures and water deficiency. The use of spraying with exogenous hormones of aromatic plants affects the accumulation and composition of volatile compounds, as well as tolerance to abiotic stress. As a result of cytokinin treatment with 6-BAP (6-benzylaminopurine) (200 mg L−l) of Anetum graveolens L. "Uzory" and "Rusich" varieties, several responses to its action were revealed: a change in the division of leaf blades, inhibition of flowering, an increase in the content of EO and its main components α-phellandrene and p-cymene in leaves, and limonene in umbels and fruits. It was revealed that the increased accumulation of EO in dill leaves was longer with sufficient moisture. In contrast, under conditions of heat and water deficiency, the effect of 6-BAP treatment on accumulations of the EO in leaves was short-lived and did not appear on umbels and fruits. The study of the cytokinin effect on a fine structure of a wax cover on the adaxial side of leaves by scanning electron microscopy revealed a change in its elements (from amorphous layers with scales to thin tubules), which probably increased the sensitivity of leaves to water deficiency and, consequently, led to a decrease in the biosynthetic activity of leaf tissue. Thus, 6-BAP had an impact on the adaptive properties of dill plants, prolonging the "youth" of vegetative organs and the ability to EO biosynthesis under conditions of sufficient moisture. [ABSTRACT FROM AUTHOR]

We investigate a nonlinear response of the physical vacuum by the example of the third harmonic in radiation of the electron–positron–photon plasma excited by a strong time dependent electric field at the focus spot of counterpropagating laser pulses. The investigation was developed within the framework of the Bogoliubov–Born–Green–Kirkwood–Yvon kinetic theory nonperturbatively describing vacuum creation of the quasiparticle electron–positron plasma (EPP) and different channels of its interaction with the photon subsystem in the single-photon approximation that are opened in the presence of a strong semiclassical field. We investigate the radiation of EPP in the annihilation channel on the basis of the well known approximations and compare the obtained result with the semiclassical radiation of the plasma oscillations. In the high-frequency range for large adiabaticity parameter the quantum radiation dominates in comparison with the semiclassical one. [ABSTRACT FROM AUTHOR]

In this work, we study long-term changes in the main directions of movement (storm tracks) of extratropical cyclones in the North Atlantic for the period 1873–2021, based on the data of the MSLP (Mean Sea Level Pressure) archives from the Climatic Research Unit and NCEP/DOE AMIP-II reanalysis. It was found that in the cold half of the year, the mean latitudes of storm tracks undergo oscillations with the periods ~80–100, ~40–45, and ~22 years, which indicates their possible association with solar cyclicity. Cyclone trajectories were found to shift northward at the minimum of the Gleissberg secular cycle (~1900–1930) and southward at its maximum (~1940–1960). The secular variations are the most pronounced in the western part of the North Atlantic, with the peak-to-peak amplitude reaching ~3–5°, and disappear at longitudes east of Greenwich. On the bidecadal timescale, cyclone tracks were found to shift noticeably to the north in even solar cycles and weakly to the south in odd ones. The most significant northward shifts (~1–2°) were detected during the descending phase and the minimum of the solar cycle (from the second to the sixth year after the solar maximum) in the eastern part of the North Atlantic (longitudes 30–10° W). The detected oscillations of cyclone trajectories may be caused by long-term changes in the intensity of the stratospheric polar vortex associated with galactic cosmic ray variations and geomagnetic activity. [ABSTRACT FROM AUTHOR]

The amidoalkylation of a phosphonous acid containing a structural isostere of diethyl glutamiate, using ethyl carbamate and 3-(methylthio)propionaldehyde, was proposed for the synthesis of NC(O)OEt-protected phosphinic pseudo-Met-Glu-peptide. Subsequent adamantyl protection of the phosphorylic function and hydrolysis of carboxylic groups made it possible to obtain phosphinic Met-[P]-Glu peptide in the form of cyclic glutamate anhydride. It was found that the latter reacts with the third amino acid component histidine to form the phosphinic Met-[P]-Glu-γ-His tripeptide. [ABSTRACT FROM AUTHOR]

A novel graphene antenna composed of a graphene dipole and four auxiliary graphene sheets oriented at 90 ∘ to each other is proposed and analyzed. The sheets play the role of reflectors. A detailed group-theoretical analysis of symmetry properties of the discussed antennas has been completed. Through electric field control of the chemical potentials of the graphene elements, the antenna can provide a quasi-omnidirectional diagram, a one- or two-directional beam regime, dynamic control of the beam width and, due to the vertical orientation of the dipole with respect to the base substrate, a 360 ∘ beam steering in the azimuth plane. An additional graphene layer on the base permits control of the radiation pattern in the θ -direction. Radiation patterns in different working states of the antenna are considered using symmetry arguments. We discuss the antenna parameters such as input reflection coefficient, total efficiency, front-to-back ratio, and gain. An equivalent circuit of the antenna is suggested. The proposed antenna operates at frequencies between 1.75 THz and 2.03 THz. Depending on the active regime defined by the chemical potentials set on the antenna graphene elements, the maximum gain varies from 0.86 to 1.63. [ABSTRACT FROM AUTHOR]