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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.