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p-NiO/n-Ga 2 O 3 heterojunction (HJ) diodes exhibit much larger changes in their properties upon 1.1 MeV proton irradiation than Schottky diodes (SDs) prepared on the same material. In p-NiO/Ga 2 O 3 HJ diodes, the narrow region adjacent to the HJ boundary is found to contain a high density of relatively deep centers with levels near E C -0.17 eV and a depleted region in the immediate vicinity of the HJ boundary. The series resistance of the HJ diodes is slightly higher than for the Schottky diodes and shows a temperature dependence with activation energy ~ 0.12 eV, like the temperature dependence of the NiO film resistivity. Irradiation with 1.1 MeV protons leads to a decrease of the hole concentration in the NiO, with a high carrier removal rate of ~ 1.3 × 10 5  cm -1 and a strong compensation of the interfacial region where the concentration of the E C -0.17 eV centers decreases with a high rate of ~ 7 × 10 3  cm -1 . The combined action of these two effects gives rise to the much stronger increase of the series resistance of the HJ diodes compared to Schottky diodes. The observed differences between the radiation response of the HJs and SDs cannot be credibly attributed to the changes of the density of any of the deep electron and hole traps detected in our experiments., Competing Interests: Declarations Competing interests The authors declare no competing interests., (© 2024. The Author(s).)

The laser-induced decay of an atomic system in an intense infrared and perturbative extreme ultraviolet (XUV) pulse is considered within Keldysh and streaking ionization channels. The streak camera method is discussed for two cases corresponding to different ranges of photoelectron momentum: i) the streaking channel significantly dominates the Keldysh channel and ii) the Keldysh channel of ionization is dominant, while two channels may interfere. The retrieval of XUV pulse parameters for these two cases is discussed and supported by numerical calculations.

Wilson disease (WD) is caused by mutations in the ATP7B gene that encodes a copper (Cu) transporting ATPase whose trafficking from the Golgi to endo-lysosomal compartments drives sequestration of excess Cu and its further excretion from hepatocytes into the bile. Loss of ATP7B function leads to toxic Cu overload in the liver and subsequently in the brain, causing fatal hepatic and neurological abnormalities. The limitations of existing WD therapies call for the development of new therapeutic approaches, which require an amenable animal model system for screening and validation of drugs and molecular targets. To achieve this objective, we generated a mutant Caenorhabditis elegans strain with a substitution of a conserved histidine (H828Q) in the ATP7B ortholog cua-1 corresponding to the most common ATP7B variant (H1069Q) that causes WD. cua-1 mutant animals exhibited very poor resistance to Cu compared to the wild-type strain. This manifested in a strong delay in larval development, a shorter lifespan, impaired motility, oxidative stress pathway activation, and mitochondrial damage. In addition, morphological analysis revealed several neuronal abnormalities in cua-1 mutant animals exposed to Cu. Further investigation suggested that mutant CUA-1 is retained and degraded in the endoplasmic reticulum, similarly to human ATP7B-H1069Q. As a consequence, the mutant protein does not allow animals to counteract Cu toxicity. Notably, pharmacological correctors of ATP7B-H1069Q reduced Cu toxicity in cua-1 mutants indicating that similar pathogenic molecular pathways might be activated by the H/Q substitution and, therefore, targeted for rescue of ATP7B/CUA-1 function. Taken together, our findings suggest that the newly generated cua-1 mutant strain represents an excellent model for Cu toxicity studies in WD., (© 2023 The Authors. Traffic published by John Wiley & Sons Ltd.)

The secondary generated radiation induced by orthogonal linearly polarized extreme ultraviolet (XUV) and infrared (IR) pulses is analyzed for the spectral region of the second XUV harmonic. The polarization-filtering-based method is utilized to separate two spectrally overlapping and competing channels, which are the XUV second harmonic generation (SHG) by IR-dressed atom and XUV-assisted recombination channel of high-order harmonic generation in the IR field [Phys. Rev. A98, 063433 (2018)10.1103/PhysRevA.98.063433]. We demonstrate the use of the separated XUV SHG channel for accurately retrieving the IR-pulse waveform and find the range of IR-pulse intensities for which this retrieving is applicable.

Russia has the largest forest area on earth. Its boreal forests officially store about 97 Pg C, which significantly affect the global carbon cycle. In recent years, forest fires have been intensifying on the planet, leading to increased carbon emissions. Here we review how differences in fire control management of Russian forests affect fire related emissions. Carbon emissions due to fire were estimated using satellite data and compared to official reports for 2001-2021. We found that the relative areas affected by fire did differ between different fire protection zones, and 89 % of the area burnt was in forests controlled by fire-fighting aircraft or areas without protection. As a result, 417.7 Mha of poor or unprotected Russian forests (42 % of total) account about a half of total carbon emissions. According to our estimates, the average area of burnt forests in Russia was about 8.3 Mha per year between 2016 and 2021, resulting in annual carbon emission of 193 million metric tons (Mt) C emissions, and 53 % of them were from unprotected forest. These estimated carbon emissions are significantly higher than official national reports (79 Mt C yr -1 ). We estimated that net carbon uptake for Russia for 2015-2021 was about 333 ± 37 Mt C, which is roughly double the official estimates. Our results highlight large spatial differences in fire protection and prevention strategies in fire related emissions. The so-called control zone which stretches across large parts of Eastern Russia has no fire control and is the region of major recent fires. Our study shows that to estimate the Russian forest carbon balance it is critical to include this area. Implementation of some forest management in the remote areas (i.e., control zone) would help to decrease forest loss and resulting carbon emissions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Alpine ecosystems represent varied climates and vegetation structures globally, with the potential to support rich and functionally diverse avian communities. High mountain habitats and species are under significant threat from climate change and other anthropogenic factors. Yet, no global database of alpine birds exists, with most mountain systems lacking basic information on species breeding in alpine habitats, their status and trends, or potential cryptic diversity (i.e., sub-species distributions). To address these critical knowledge gaps, we combined published literature, regional monitoring schemes, and expert knowledge from often inaccessible, data-deficient mountain ranges to develop a global list of alpine breeding bird species with their associated distributions and select ecological traits. This dataset compiles alpine breeding records for 1,310 birds, representing 12.0% of extant species and covering all major mountain regions across each continent, excluding Antarctica. The Global Alpine Breeding Bird dataset (GABB) is an essential resource for research on the ecological and evolutionary factors shaping alpine communities, as well as documenting the value of these high elevation, climate-sensitive habitats for conserving biodiversity., (© 2022. The Author(s).)

We propose to use the generation of even Brunel harmonics (BHs) by optical laser pulses for high-resolution gas-biased coherent detection of lower-frequency radiation in terahertz and mid-infrared ranges. BHs arise due to the acceleration of electrons liberated in the tunneling ionization process, and BHs pulses are much shorter than the laser ones. The latter makes it possible to significantly increase the temporal resolution of sampling detection compared to the use of cubic response of bound electrons generating the second harmonic of the gating pulse. However, as we show by solving the time-dependent Schrödinger equation for the helium atom, for an intense linearly polarized laser pulse, the atomic response contains a broadband noise signal that interferes with BHs and allows the detection of very high electric fields only. We show that the nature of this noise is related to the population of the Rydberg states of the atom, which can be effectively suppressed by using elliptical polarization of the gating pulse.

With increased forest fires due to climate change, PM 2.5 emissions also intensified. Record PM 2.5 emissions according to Copernicus Atmosphere Monitoring Service in Russia amounted to 8 megatons (Mt) in 2021, which is 78% higher than the average level of 2004-2021 (4.5 Mt). Seven federal subjects (the constituent entities) with vast forest areas without fire protection produced 86% of emissions (6.8 Mt) in 2021, the major losses (6.1 Mt) in Yakutia (Sakha Republic). The ambient temperature in Eastern Siberia is increasing, especially in months of winter and spring seasons (up to +3.6 °C) in 1990-2020 compared to 1901-2020 (CEDA Archive); climate change has affected meteorological conditions leading to increased forest fires. The results of the SARIMAX model study for PM 2.5 emissions considering meteorological factors using ERA5 and burnt forest area using MODIS (MCD64A1), establishing a significant dependence of PM 2.5 emissions on the lack of precipitation and the associated parameters of complete and potential evaporation. This influence long before the fire season (up to 9 months), as it affects the snow cover and the dryness of the fuel by the beginning of forest fires. In turn, high PM 2.5 emission values are accompanied by a drop in 2 m air temperature and surface solar radiation downwards due to the aerosol saturation with suspended particles. The average COR for seven federal subjects was 0.79, with the highest forecast result in Yakutia (0.95), indicating the maximum propensity for record emissions due to weather conditions. In combination with forest management without fire protection, meteorological parameters have caused an increase in PM 2.5 emissions in recent years in Siberia. The forest needs other ways to manage under the pressures of climate change to reduce environmental pollution associated with PM 2.5 emissions from vast Siberian fires., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

We analyze the polarization response of a single Ne atom in an intense infrared (IR) laser field and weak extreme ultraviolet (XUV) isolated attosecond pulse (IAP). The analysis is based on the numerical solution of the time-dependent Kohn-Sham equations and the recently developed perturbation theory in the XUV field for an atom subjected to an intense IR field. In our numerical results, we observe a significant increase in the magnitude of the atomic polarization response at the frequencies near the carrier frequency of the IAP and associate it with XUV-induced collective dynamics contributing to the polarizability of Ne. The specific interference between IR- and XUV-induced channels is discussed, and its utilization for retrieving the phase of the generated harmonics in the IR field is suggested.

Employing classical isothermal molecular dynamics, we simulated coalescence of mesoscopic Au nanodroplets, containing from several thousands to several hundred thousands of atoms, and sintering of mesoscopic solid Au nanoparticles. For our atomistic simulations, we used the embedded atom method. The employed open access program large-scale atomic/molecular massively parallel simulator makes it possible to realize parallel graphical processing unit calculations. We have made a conclusion that the regularities and mechanisms of the nanodroplet coalescence (temperature is higher than the nanoparticle melting temperature) and of the solid nanoparticle sintering differ from each other. We have also concluded that the nanodroplet coalescence may be interpreted as a hydrodynamic phenomenon at the nanoscale whereas sintering of solid nanoparticles is a much more complex phenomenon related to different mechanisms, including collective rearrangements of atoms, the surface diffusion, and other types of diffusion. At the same time, collective rearrangements of atoms relate not only to the solid nanoparticle sintering but also to the nanodroplet coalescence. In general, our molecular dynamics results on sintering of Au nanoparticles consisting of 10 000-30 000 atoms agree with the Ferrando-Minnai kinetic trapping concept that was earlier confirmed in molecular dynamics experiments on Au nanoclusters consisting of about 100 atoms.

An all-optical method is suggested for the metrology of an isolated, pulse-to-pulse stabilized attosecond pulse. It is shown analytically that high-order harmonic generation (HHG) yield for an intense IR pulse and time-delayed attosecond pulse keeps encoded waveform of the attopulse, which can be decoded by the time delay measurements of the HHG yield. The retrieval method is demonstrated by modeling HHG from Ne atom within time-dependent Kohn-Sham equations. The application of the suggested method for monitoring the carrier-envelope phase of the attosecond pulse is discussed.

Interpretation of strong-field phenomena is mostly based on the analysis of classical electron trajectories in an intense laser field, whose specific properties determine general features of nonlinear laser-matter interaction. Currently, the visualization of closed electron trajectories contributing to high harmonic generation (HHG) of the laser field is the prerogative of a theoretical analysis based on the time-frequency spectrogram of the induced dipole acceleration. Here, we propose a method for direct reconstruction of the HHG time-frequency spectrogram using a time-delayed probe XUV pulse. Our analytical theory and ab initio numerical simulations demonstrate that the XUV-assisted HHG yield as a function of time delay and harmonic energy mimics the short-time Fourier transform of the dipole acceleration induced by the laser field, thereby providing possible in-situ experimental access for tracing electron dynamics in strong-field phenomena.

We propose and investigate a method for generating tunable and phase-controllable mid- and far-infrared pulses in gas ionized by an intense two-color laser field composed of the chirped fundamental and its second-harmonic pulses with group time delay. The generation frequency equals the difference between the second-harmonic and the doubled fundamental frequencies and is continuously tunable by varying chirp or time delay. The duration of the generated pulses is determined by the ionization duration, which is much shorter than the ionizing pulse and is controlled by laser-pulse stretching or changing its intensity. Our quantum-mechanical calculations and analytical description show that this method can provide a wide tuning range spanning from several to more than a hundred THz using femtosecond lasers.

By light microscopy, the morphofunctional state of mesonephros was studied for various sturgeons and bony fishes taken from natural waters. Different changes were recorded in structural-functional elements of nephrons of the mesonephros. The most frequent disturbances are hemorrhages in the intertubule tissue of kidneys, hyalinosis of vessel walls, swollen epithelium, inflammations. The revealed disturbances may be regarded as a response to negative environmental impacts.

Data on the frequency of peripheral Treg cells, their functional activity, as well as their relationship to changes in characteristics of cellular immunity in patients with colorectal cancer (CRC, n=42) and healthy donors (n=34) are presented in the article. Assessment of the expression of molecular markers of lymphocytes was performed by multicolor flow cytometry. It was shown that the number of these cells is significantly increased in CRC patients (p<0,05). Probably CD4+CD25+FOXP3+ Treg cells may play a more substantial role in the periphery during the initial period of tumor formation, whereas CD8+FOXP3+ Treg cells are important in the later stages of the disease. In CRC patients, the increase of the functional activity of Treg cells (CD4+CD25+CD127lo/‘) on the expression of inhibitory molecules CTLA-4 and the marker of cell proliferation Ki-67 was observed. In patients with CRC, the frequency of peripheral Treg cells and the expression level of CTLA-4 were inversely correlated with the number of CD3+CD4+ T-helper cells.

Purpose: To assess ischemia-reperfusion injury of renal allograft by microdialysis., Design: A pilot, single-center; prospective study., Patients and Methods: The study included 7 patients (4 males and 3 females, average age was 46.71 ± 6.53 years) after cadaveric kidney allograft transplantation (CKA) under general combined anaesthesia., Conclusions: Microdialysis provides an opportunity of continuous monitoring of metabolic changes in the tissue of transplanted kidney. The main advantage of the monitoring by microdialysis is an opportunity of early identifying of ischemia-reperfusion complications. Thus, early assessment of CKA by microdialysis can be for the improving of patient's treatment in the early post operative period. Further clinical studies must be done to define the role of microdialysis.

Comparative analysis of using tumor markers in 159 patients with colorectal cancer was made. Carcinoembryonal antigen, skin reaction of hypersensitivity of slow type with autologous modified lymphocytes and a diagnostic test of tumor growth were used as oncomarkers. Each of three markers may be used for preoperative staging of colorectal cancer, postoperative monitoring of patients and determination of the disease prognosis. An individual approach of assessment of the oncomarker level at different stages of examining the patient is recommended.

The purpose of the study was to assess the functional state of endothelium and vascular stiffness using biochemical parameters and non-invasive instrumental methods of examination before and after specific treatment of patients with early forms of syphilis. A total of 51 patients with early syphilis were examined, 30 healthy individuals served as controls. Blood C-reactive protein, fibrinogen, and sialic acid levels were measured. Rigidity index was estimated using a Pulse Trace photopletizmograph (Micro Medical, England). Patients with early forms of syphilis had markedly increased concentrations of CRP, fibrinogen, sialic acids (markers of inflammation) and the ridgidity index both before and after specific therapy.

The purpose of the study was to investigate arterial oxygenation and hemodynamics during and after alveolar mobilization in the early post-cardiopulmonary bypass (CPB) period of cardiac surgery. The study involved 21 patients aged 30 to 73 years, who had a PaO2/FiO2 below 300 mm Hg in the early post-CPB period. PaO2/FiO2 was less than 200 mm Hg in 4 patients. Alveolar mobilization was performed by means of the "Open lung tool" function of a Servo-i respirator ("Maquet'). PaO2/FiO2 significantly increased (P < 0.5) from 244+/-11 to 472+/-20 mm Hg and thoracopulmonary compliance (Cdyn) increased from 53.3+/-3 to 67.5+/-2.9 ml/cm H20 (p < 0.5). Intrapulmonary shunt (Qs/Qt) significantly decreased from 14+/-1 to 10+/-1.5% (p < 0.5). The mean values of PaO2/FiO2 Cdyn and Qs/Qt were stable at the end of procedures. PaO/FiO, was greater than 350 mm Hg in 62% of the patients. Cardiac index considerably decreased from 2.7+/-0.1 to 225+/-0.1 l/min/m(2) at the peak of alveolar mobilization (p < 0.05); right atrial pressure and mean pulmonary artery pressure were moderately, but significantly higher at that moment. Hemodynamic parameters returned to the baseline levels after alveolar mobilization. There were no significant hemodynamic complications. It is concluded that alveolar mobilization is an effective technique in improving arterial oxygenation and lung biomechanics in cardiosurgical patients under anesthesia.

Aim: To compare high-resolution ultrasound of major arteries and the method of vascular stiffness evaluation by digital volume pulse photoplethysmography after sublingual nitroglycerin in diagnosis of structural vascular changes., Material and Methods: The comparison of the two methods was made in 110 volunteers (mean age 31.9 +/- 11.5 years). The study protocol included measurement of blood pressure (BP), blood lipids and glucose, evaluation of IMT of the carotid arteries by ultrasonography, baseline stiffness index (SIbl) and after sublingual nitroglycerin (SIng) by photoplethysmography. Reproducibility of photoplethysmography was evaluated in 20 volunteers (mean age 20.3 +/- 1.4 years) with repeated measurement after 1 week. The results were tested in 40 volunteers of different age groups., Results: There were significant correlations of IMT, SIbl and SIng with risk factors and close interrelations of these parameters. SIng better explained variability of IMT compared to SIbl (r = 0.79, R2 = 0.62, p < 0.001 versus r = 0.67, R2 = 0.45, p < 0.001, respectively). Relations of IMT with risk factors were lost after correction for SIng. Reproducibility of SIng was higher than SIbl (+/- 5.1% versus +/- 10.9%, respectively) and than those for IMT found in the literature. Mean IMT values for random sample evaluated by ultrasonography and calculated by estimated equation of linear regression for SIng and IMT did not differ significantly (0.576 +/- 0.087 mm versus 0.570 +/- 0.074 mm, p = 0.44; r = 0.71, p < 0.001, mean difference 0.007 +/- 0.051 mm)., Conclusion: The method of vascular stiffness measurement is comparable with ultrasonography in terms of vessel structure evaluation and possesses higher reproducibility. The test with nitroglycerin substantially increases its diagnostic potential and reproducibility.

This study examines the impact of fire incidents on wildlife and habitats in the western oak forests of Iran (Zagros region). These forests are globally recognized for their exceptional biodiversity but are frequently threatened by wildfires. To achieve this, the study uses the space–time scan statistics permutation (STSSP) model to identify areas with a higher frequency of fires. The study also analyzes the effects of fires on the Zagros forests from 2000 to 2021 using remote-sensing MODIS data. Also, to understand the elements at risk of fire, burned areas were assessed based on the richness of vertebrate species, determined by the distribution of 88 vertebrate species. The results show that the annual fire rate in the Zagros forests is 76.2 (fire occurrences per year), calculated using the Poisson distribution. Findings show the highest fire rates are found in the northwest and a part of the south of the Zagros. The northwest of the Zagros also has the largest number of single fires and clusters, indicating a wide spatial distribution of fire in these regions. On the other side, it was unexpectedly found that these regions have the richest number of species and higher habitat value. The results demonstrate a significant correlation between the value of the habitat and the extent of burned areas (p < 0.05). The study also reveals that the greatest impact of fires is on small vertebrates. The overlap of frequent fire spots with the richest regions of Zagros oak forests in terms of vertebrate diversity emphasizes the need for strategic forest risk reduction planning, especially in these priority zones. [ABSTRACT FROM AUTHOR]

The intense Siberian wildfires in the summer of 2019 had devastating effects. Here the dynamics of these wildfires is described taking into consideration the legal act that determines modern forest management in Russia -- the Forest Code-2006. This changed the approach to wildfire management in Russia by introducing control zones, where authorities can legally ignore wildfires due to their inaccessibility or remoteness from firefighting infrastructure. Remote sensing and open reports show that most wildfires (60--98%, depending on the day) in Siberia in 2019 were in control zones. Notably, the largest percentages were recorded during the crucial phases of the wildfires, including their rapid spread in June (97--98%) and during the peak from on 2 August (96%), when 3,012,082 of 3,134,128 hectares were on fire. The decision not to fight these wildfires was debatable given the considerable social concerns expressed online during the peak of the wildfires, which later resulted in civic petitions in favour of fighting wildfires more efficiently in Siberia. Based on previous reports by experts there is an urgent need to incorporate a more scientific approach in defining control zones in Siberia, to balance the current economic and socioenvironmental considerations. Otherwise, the control zones of Russian forests (occupying 48% of Russia's and 11% of the global forest area, respectively) will remain a critical blind spot in climate change mitigation plans that aim to utilize Siberia's carbon sequestration potential. [ABSTRACT FROM AUTHOR]

Based on the photocurrent model, we theoretically investigate the terahertz (THz) radiation in gas plasma driven by monochromatic chirp laser pulse. It is shown that the trajectories of the ionized electrons can be controlled effectively and can form a larger net residual current in a chirped field. As a result, the radiated THz yield can be dramatically improved by nearly more than two orders of magnitude than that of few-cycle chirp-free laser field. Furthermore, with the THz yield dependence on the laser intensity, wavelength and pulse width of the drivers carefully investigated, some noticeable differences between chirped field and chirp-free pulse are observed. [ABSTRACT FROM AUTHOR]

Predicting wildfire spread behavior is an extremely important task for many countries. On a small scale, it is possible to ensure constant monitoring of the natural landscape through ground means. However, on the scale of large countries, this becomes practically impossible due to remote and vast forest territories. The most promising source of data in this case that can provide global monitoring is remote sensing data. Currently, the main challenge is the development of an effective pipeline that combines geospatial data collection and the application of advanced machine learning algorithms. Most approaches focus on short-term fire spreading prediction and utilize data from unmanned aerial vehicles (UAVs) for this purpose. In this study, we address the challenge of predicting fire spread on a large scale and consider a forecasting horizon ranging from 1 to 5 days. We train a neural network model based on the MA-Net architecture to predict wildfire spread based on environmental and climate data, taking into account spatial distribution features. Estimating the importance of features is another critical issue in fire behavior prediction, so we analyze their contribution to the model’s results. According to the experimental results, the most significant features are wind direction and land cover parameters. The F1-score for the predicted burned area varies from 0.64 to 0.68 depending on the day of prediction (from 1 to 5 days). The study was conducted in northern Russian regions and shows promise for further transfer and adaptation to other regions. This geospatial data-based artificial intelligence (AI) approach can be beneficial for supporting emergency systems and facilitating rapid decision-making. [ABSTRACT FROM AUTHOR]

This study investigated the effect of trimethylgallium flow rate on the structural and photoelectronic properties of β-Ga2O3 films grown on α-Al2O3 (0001) substrates using MOVPE method. As the source flow rate gradually decreased from 7.2 mol/min to 3.6 mol/min, the films gradually changes from polycrystalline to a single epitaxial orientation, and the epitaxial relationships between the film and the substrate were β-Ga2O3 ( 2 - 01) ∥α-Al2O3 (0001) and β-Ga2O3 [010] ∥α-Al2O3 < 1 - 010>. The film thickness was reduced from 767.4 to 329.2 nm and the surface root-mean-square roughness decreased from 18.1 to 5.84 nm. The average transmittance in the visible range increased from 81.2 to 83.4%, and the optical bandgap width increased from 4.80 to 4.95 eV. The prepared MSM-structured photodetectors (PDs) could continuously switch response to 254 nm UV light, and the PD prepared at 7.2 mol/min source flow rate had a maximum photo current of 1405.2 nA. However, the PD prepared under the condition of 3.6 mol/min had the lowest dark current, the highest photo-dark current ratio, shorter fast response time, and a good retention characteristic. [ABSTRACT FROM AUTHOR]

Spatiotemporal analysis provides valuable insights into spatial variations through time series of outgoing longwave radiation (OLR) in a seismically active region. This study investigates the relationship between the anomalous variations in OLR associated with the earthquake preparation process for earthquakes (Mw > 6.0) in the Sumatra region radius of 75 km from 1993 to 2012 concerning the 26 December 2004 Sumatra–Andaman Islands earthquake. To explore the spatiotemporal characteristics of OLR, the grid comprising 11° × 11° was considered for a 12-month time period preceding the earthquake. The spatial distribution of the anomalous OLR flux is investigated over and around the epicentral region to indicate a region's earthquake preparation process. The entire spatial extent is categorized into two leagues, "Macro dimension League" (MaDL) and "Micro dimension League" (MiDL). To facilitate the comparison of different grid dimensions, the OLR values of the grids are normalized. The authors inferred that the anomalous variations observed in MiDL are more predominant than in other regions, mainly 1–3 months before earthquakes. These anomalous variations may serve as precursory signals manifesting as a thermal release near and over the epicentral region. It might indicate the earthquake preparation process over the seismically vulnerable regions with a magnitude greater than 6.0 Mw. Hence, the study suggests that the anomalous changes in OLR could be considered as a precursor in earthquake precursory studies, at least in this confined study region. [ABSTRACT FROM AUTHOR]

Coastal zones supporting diurnal shelf waves near the South Kuril Islands were determined based on the analysis of small-scale amplitude and phase variations of diurnal O1 and K1 tidal waves estimated from along-track TOPEX/Poseidon altimetry data. The amplitudes and phases of these waves were revealed not only along the original tracks (1992–2002), but also along those shifted by half the intertrack distance (2002–2005). This made it possible to more accurately determine the zone supporting diurnal shelf waves. It was found that diurnal shelf waves in the form of baroclinic coastal trapped modes strongly influence tidal motions on the oceanic shelf of Urup and Iturup islands. Two wavelengths fit in this section of the shelf (one pair of quasi-stationary eddies is localized on the shelf of Urup Island and a second one on the shelf of Iturup Island). This is an unexpected result, as barotropic shelf modes usually form one pair of eddies (for example, on the northeastern shelf of Sakhalin Island, on the northern shelf of Hokkaido Island and on the oceanic shelf of the North Kuril Islands). We found that the zone of K1 and O1 tidal waves start from Chirpoi Island, which means that shelf waves are generated as a result of the diffraction of a large-scale Kelvin tidal wave in the deep Bussol Strait. The existence of the lower frequency O1 tidal shelf wave was found not only on the shelf of Urup and Iturup islands, but also on the shelf of Shikotan Island, which is consistent with the earlier results of Yefimov and Rabinovich (1980). Diurnal shelf waves cause significant increases in the O1 and K1 amplitudes on the coast of Iturup Island (especially at its southern part) and on Urup Island in comparison with the open ocean, and produce strong instrumentally-observed diurnal tidal currents in these regions. Baroclinic diurnal shelf (coastal trapped) waves also contribute to vertical movements, forcing water temperature variations at sufficiently great depths, which can have a significant impact on the living conditions of benthic communities. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs), are porous crystalline structures comprising of metal ions or clusters intricately linked with organic entities, displaying topological diversity and effortless chemical flexibility. These characteristics render them apt for multifarious applications such as adsorption, separation, sensing, and catalysis. Predominantly, the distinctive properties and prospective utility of MOFs are discerned post-manufacture or extrapolation from theoretically conceived models. For empirical researchers unfamiliar with hypothetical structure development, the meticulous crystal engineering of a high-performance MOF for a targeted application via a bottom-up approach resembles a gamble. For example, the precise pore limiting diameter (PLD), which determines the guest accessibility of any MOF cannot be easily inferred with mere knowledge of the metal ion and organic ligand. This limitation in bottom-up conceptual understanding of specific properties of the resultant MOF may contribute to the cautious industrial-scale adoption of MOFs. Consequently, in this study, we take a step towards circumventing this limitation by designing a new tool that predicts the guest accessibility—a MOF key performance indicator—of any given MOF from information on only the organic linkers and the metal ions. This new tool relies on clustering different MOFs in a galaxy-like social network, MOFGalaxyNet, combined with a Graphical Convolutional Network (GCN) to predict the guest accessibility of any new entry in the social network. The proposed network and GCN results provide a robust approach for screening MOFs for various host–guest interaction studies. [ABSTRACT FROM AUTHOR]

Combined investigations have shown that the pulmonary syndrome in chronic liver diseases is a group of changes (heterogeneous in their structure and origin), most of which are of intercurrent nature (chronic bronchitis and its complications, chronic pneumonia), the lesser part of them is related directly to an inflammatory liver process and constitutes the true pulmonary syndrome (interstitial pneumonitis, fibrosing alveolitis). In view of the fact that chronic liver pathology is attended by concomitant disorders of pulmonary ventilation, hemodynamics and immunologic homestasis, the authors propose that they should be regarded as a risk factor contributing to the development of respiratory diseases.

Employing the isothermal molecular dynamics and the embedded atom method, we simulated melting of metallic nanoparticles (Au, Ag, Cu, Ni, and Pb ones). In more detail, the results for Au and Ag nanoparticles are presented and discussed. At first, we analyzed the behavior of the temperature dependences for the potential (cohesive) term into the specific (per atom) internal energy and for the degree of crystallinity in the course of heating nanoparticles. We have found that the results obtained for nanoparticles of about 4 and 8 nm in size (containing 2093 and 20,113 atoms, respectively) demonstrate the continuous melting. Employing the dependence of the specific potential energy on the distance to the nanoparticle center of mass and the common neighbor analysis, we showed that the continuous melting occurs via the surface pre-melting mechanism. Then, we evaluated the self-diffusion coefficient in the surface disordered layers of Au and Ag nanoparticles and found that our results agree in order of magnitude (10−9 m2/s) with the values of the self-diffusion coefficient for the bulk Au and Ag melts at the corresponding bulk melting temperatures. Finally, combining in our molecular dynamics experiments continuous heating Au nanoparticles with annealing them at some constant selected temperatures, we have shown that the liquid nucleation and growth mechanism should be most adequate to the melting behavior of metallic nanoparticles. [ABSTRACT FROM AUTHOR]

Defects created in lightly Sn-doped (2 × 1016 cm−3) (010)-oriented bulk β-Ga2O3 implanted with 1.2 MeV, 3 × 1015 cm−2 197Au+ ions before and after treatment in hydrogen plasmas at 330 °C were studied by X-ray measurements, Rutherford backscattering spectra, capacitance–voltage, current–voltage, admittance spectra and deep level transient spectroscopy. Au implantation creates defects that produce total depletion of carriers in the top 1.5 µm and introduces electron traps with energy levels at Ec-0.7 eV, Ec-1.05 eV, Ec-0.45 eV, and deep acceptors with optical ionization thresholds near 1.3 eV, 2.3 eV and 3.1 eV, similar to the centers dominating the spectra of deep traps in β-Ga2O3. Hydrogen plasma treatment greatly enhances the photocurrent and photo-capacitance and decreases the width of the insulating layer produced by Au implantation. The results can be explained by hydrogen passivation of the triply charged Ga vacancies and doubly charged split Ga vacancies acceptors in the implanted region, returning part of this region to n-type conductivity. [ABSTRACT FROM AUTHOR]

Bird diversity research in this area has revealed that the eastern Himalaya mountain range, south slopes, and mid-lower altitude areas have higher levels of bird diversity than the western Himalaya mountain range, north slopes, and high-altitude areas, respectively (Acharya I et al i . The results of most studies on the altitude gradient distribution of birds carried out in the Himalaya mountain area showed that the abundance of birds firstly increased and then decreased with the change of altitude and that the areas with the highest abundance were generally in the range of 2000-3000 m (Acharya I et al i . However, the survey can generally reflect the changing trend of bird abundance in the large Mount Everest altitude gradient, which will help to understand the condition of birds at extremely high altitudes. The species and abundance of birds in the high altitude area of Mount Everest decreased sharply with the increase of altitude. [Extracted from the article]

We have accurately recalculated the embedding functions for Pt and Pd in the frames of the basic embedded atom method (EAM) scheme primarily developed by Daw and Baskes. The main motivation behind such a problem is that some later EAM parameterizations inadequately predict for Pd a higher melting temperature than for Pt. So, other results obtained by employing these parameterizations are also called into question. Our numerically calculated EAM functions for Pt and Pd were verified theoretically and in molecular dynamics simulations of bulk Pt and Pd phases as well as of Pt, Pd, and binary Pt–Pd nanoparticles. In particular, bulk densities in the solid and liquid states, temperatures and heats of melting, and bulk moduli of Pt and Pd were evaluated. Besides, the elastic constants C 11 , C 12 , and C 44 were theoretically recalculated. All the verification results at least satisfactorily agree with the available experimental data. One of the advantages of our embedding functions is that they are suitable for atomistic simulations of Pt- and Pd-based alloys as well. In particular, our embedding functions quite adequately predict segregation of Pd atoms to the surface of binary Pt–Pd nanoparticles. [ABSTRACT FROM AUTHOR]

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Background The North Caucasus is an extensive region with a multitude of landscapes and high biological diversity. Amongst various ecosystems, the xerophytic sub-Mediterranean forests of the Abrau Peninsula (Utrish State Nature Reserve) and its vicinity are unique but have been poorly studied. The diversity of diatoms in North Caucasian ecosystems have been studied partially and only little information is available about their presence and distribution on the Abrau Peninsula. Here, we present a comprehensive check-list of diatoms sampled during a July 2021 field campaign. Samples were collected in 67 sites, including 39 permanent streams, 21 temporal (puddles) and seven permanent waterbodies. Results of the current study contribute to improving the knowledge about diatoms in the north-western Caucasus and its sub-Mediterranean ecosystems in particular. [ABSTRACT FROM AUTHOR]

Sialic acid is a terminal component of carbohydrate chains of glycoproteins and glycolipids. The present study estimated total sialic acid (TSA) and its ratio with total proteins (TP), in serum and saliva of preeclampsia. The study further investigated the association of these parameters with clinical variables of disease progression. 50 preeclampsia patients (32 mild preclampsia and 18 severe preeclampsia cases) and 50 pregnant controls were included in the study. Serum and salivary free sialic acid, protein bound sialic acid and TP were measured spectrophotometrically. Serum and salivary TSA and its ratio with TP were calculated. There was a significant increase in serum TSA and its ratio with TP in preeclampsia compared to the controls. The increase reflected with the severity of the disease. Serum TSA and TSA/TP showed a significant positive correlation with blood pressure, proteinuria and a significant negative correlation with infant birth weight. In saliva, there was no statistical difference between TSA in preeclampsia and controls. Salivary TSA/TP increased significantly in preeclampsia. However the increase was not in accordance to the disease severity. Salivary TSA and TSA/TP were not significantly associated with any of the clinical parameters of disease progression. Significant increase in seum TSA reflects the disturbance in sialyation of serum proteins in preeclampsia, that could not be depicted in the saliva of these patients. Disturbance in serum protein sialyation is further exaggerated with the severity of the disease. Serum TSA and TSA/TP and not the respective salivary parameters, could serve as useful indicators in assessment of clinical progression of the disease. [ABSTRACT FROM AUTHOR]

The work is devoted to the study of the mechanical properties of porous ceramics based on diatomite, which has high porosity, adsorption capacity, weak thermal and acoustic conductivity, refractoriness and acid resistance. Based on the morphological analysis of the samples, the numerical value of the sample's porosity was determined. The mechanical properties of the samples were determined by static and dynamic loading methods. The values of static and dynamic elastic moduli of the samples were experimentally measured. The research results showed that, for the material under consideration, at the initial stages of compression processes, the processes of elastic deformation are mainly realized with the subsequent transition to the region of plastic deformation. It was also found that for highly porous samples in the elastic deformation region, the manifestation of pressing processes is possible. In this work, the study of the dependence of the dynamic modulus of porous diatomite ceramics on porosity was carried out: a decrease in elastic moduli was recorded with an increase in the material porosity. A decrease in material porosity after deformation is found. [ABSTRACT FROM AUTHOR]

Many researchers have recognized the long distance teleconnections between El Niño–Southern Oscillation (ENSO) events and some other processes in the global climate system happening in areas often very far from the equatorial zone of the Pacific Ocean. In this paper we investigate similar links between ENSO and extratropical processes taken in their whole set. For this goal we compute differences between the sea-level pressure and the near-surface air (sea surface) temperature global fields which correspond to either El Niño or La Niña events observed since the end of the XIX century and up to the beginning of the XXI century. As a result, we establish that an integrity exists of ENSO and the extratropical teleconnections such as North Atlantic Oscillation (NAO), Arctic Oscillation (AO), the Northern Hemisphere annular (NHA) mode as well as the Pacific–North American (PNA) pattern, and their analogs in the Southern Hemisphere in the interannual timescale. Named this integrity the Global Atmospheric Oscillation (GAO), we define two representative indices of GAO, and investigate the temporal dynamics of these indices. This investigation reveals that GAO's extratropical components may be real irrespective of ENSO while the latter accompanies GAO in all cases. Moreover, in view of a general eastward propagation of the GAO as a spatial structure, some its extratropical components show changes of their features prior the El Niño (La Niña) begins to form. Using these features as fingerprints of the forthcoming evolution of ENSO, we define another GAO index for the El Niño prediction with the lead-time of about 1 year. At last, we establish that some of the CMIP5-models reproduce GAO reasonably well. [ABSTRACT FROM AUTHOR]

The review-and-analytical article deals with the interrelation between demographic transition and national security. The focus is on the countries of the former Soviet Union. It proves that along with two traditional approaches of population policy, i.e. prevention and overcoming of negative consequences of demographic transition, measures of adjustment to demographic change are acquiring increasing importance. [ABSTRACT FROM AUTHOR]

At the start of the third millennium, new opportunities have arisen in biogeographical research, namely in the generalisation, visualisation and cross-spectrum analysis of biological and geographical information and in the compilation of biogeographical maps and innovative models for regions that differ in the availability of distribution data. These tasks include long-term monitoring of plants and animals which are in danger of extinction, geographical analysis of biodiversity distribution and development of effective wildlife conservation strategies for specific regions. The studies of the Department of Biogeography of Moscow University on geography and biodiversity conservation are based on long-term field expeditions. The examples of the Asian Subarctic Mountains, the steppes of Central Kazakhstan and the urbanised north-west of Russia are used to illustrate Russian approaches to the use of biogeographical monitoring for the identification of priority areas for biodiversity conservation. The species populations of the higher plants and vertebrates listed in the Red Books have been considered as the basic units of biodiversity. [ABSTRACT FROM AUTHOR]

Maturation is one of the most important life history traits that influences on many ecological characteristics of animals. This study aimed to describe the indirect distinguish of first reproduction and habitat shift (transition from the pelagic to benthic environment), using the width of translucent and annuluses of the pectoral fin spine of two sturgeon species, Persian sturgeon, Acipenser persicus, and starry sturgeon, Acipenser stellatus. Interpretation of growth bands in pectoral fin sections was done objectively using direct reading of thin sections and image analysis. The results showed that changes in the profiles of translucent and annuluses occurred at the time of habitat shift and first reproduction. Females of both sturgeons move to the deeper waters earlier than males, which can be considered as strategy for the prolonged gonad development of female individuals. Estimated age at maturity for A. persicus (9 years for female and 7 years for male) was higher than A. stellatus (7 years for female and 6 years for male), which coincide with abrupt reduction in annuli width. Marks of habitat shift and first reproduction in the pectoral fin spine are species-specific characters and enable life history traits to be identified. [ABSTRACT FROM AUTHOR]