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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.

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.

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.

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.