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Abstract The frozen mummy of the large felid cub was found in the Upper Pleistocene permafrost on the Badyarikha River (Indigirka River basin) in the northeast of Yakutia, Russia. The study of the specimen appearance showed its significant differences from a modern lion cub of similar age (three weeks) in the unusual shape of the muzzle with a large mouth opening and small ears, the very massive neck region, the elongated forelimbs, and the dark coat color. Tomographic analysis of the mummy skull revealed the features characteristic of Machairodontinae and of the genus Homotherium. For the first time in the history of paleontology, the appearance of an extinct mammal that has no analogues in the modern fauna has been studied.

In the recent years, there has been a burgeoning interest in Takotsubo syndrome (TTS), which is renowned as a specific form of reversible myocardial dysfunction. Despite the extensive literature available on TTS, clinicians still face several practical challenges associated with the diagnosis and management of this phenomenon. This potentially results in the underdiagnosis and improper management of TTS in clinical practice. The present paper, the first part (part-1) of the consensus report, aims to cover diagnostic and therapeutic challenges associated with TTS along with certain recommendations to combat these challenges.

Takotsubo syndrome (TTS) still remains as an enigmatic phenomenon. In particular, long-term challenges (including clinical recurrence and persistent symptoms) and specific entities in the setting of TTS have been the evolving areas of interest. On the other hand, a significant gap still exists regarding the proper risk-stratification of this phenomenon in the short and long terms. The present paper, the second part (part-2) of the consensus report, aims to discuss less well-known aspects of TTS including specific entities, challenges after recovery and risk-stratification.

The rehabilitation of pediatric patients with oncology diseases localized in the maxillofacial area is a complex and long-term process. Most frequently, the resection area involves the maxilla or the mandible, which, in turn, impairs the functioning of the whole dentofacial system. The restoration of the integrity of the facial structures is the key task in the treatment of such patients. One of the main materials used for reconstructing the jaws is the titanium alloy. However, despite its beneficial properties and characteristics, there is a high risk of inflammation, encapsulation or failure of the endoprosthesis. The aim of the research was to analyze the data available up to date on the methods of perfecting the surfaces of titanium endoprostheses based on the published research works. After analyzing the articles devoted to the modification of the surface of titanium constructions used for endoprosthetics, for the period from 2008 until 2022 (n=41), we came to a conclusion that the modification of the surface of titanium endoprostheses results in an increase in its osteointegration, which decreases the risks of failure for the constructions.

A method of measuring the thermovoltaic effect in heterogeneous media with gradient doping impurity distributions producing gradient carrier distributions has been proposed. Iron doped zinc oxide specimens have been produced using ion beam sputtering on thin foil tantalum substrates for thermovoltaic effect measurements, glass-ceramic substrates for Hall measurements and silicon substrates for structural study. The doping impurity concentration хFe in the specimens has been varied from 0.34 to 4.18 at.%. X-ray phase analysis has shown that all the specimens have a hexagonal zinc oxide crystal structure. The films have preferential [002] orientation. The carrier concentration in the experimental specimen layers according Hall data obtained on an ECOPIA 5500 measurement system in a 0.5 T DC magnetic field has varied in the 1016–1020 cm-3 range. The specimens have an n-type conductivity. Thermovoltaic measurements have been carried out for two-layered iron doped zinc oxide specimens with different carrier and iron doping impurity concentrations using the method proposed. The maximum thermovoltaic response (U ~ 80 μV) has been observed in the two-layered thin-film specimen with the carrier concentration difference between the layers (Δn ≈ 2∙103 cm-3). The observed saturation of the thermovoltaic response has been attributed to the establishment of dynamic equilibrium between carrier diffusion from the high carrier concentration layer to the low carrier concentration layer and carrier drift due to internal electric field.

Abstract Microorganisms are a significant cause of damage to cultural heritage, including paintings. Currently, the palette of antiseptics that are used in painting has narrowed considerably. This is due to the increased demands placed on such substances. It was shown that low molecular weight chitosan (LMWC) obtained from the king crab (Paralithodes camtschaticus) exhibits high activity against dominant fungi-destructors of paintings in the State Tretyakov Gallery. Nevertheless, the increasing market demand for chitosan has prompted the exploration of alternative sources. Insects, notably the bioconverter black soldier fly (Hermetia illucens), stand out as one of the most cultivated options. This study investigates the effectiveness of chitosan, isolated from H. illucens by a novel method developed by authors, in inhibiting fungi that damage tempera paintings. The activity of 33 and 39 kDa chitosans from H. illucens is comparable to the most active chitosans previously studied from P. camtschaticus. However, there are characteristic differences between these compounds, as shown by the results of FTIR spectroscopy, which may affect their consumer properties when used in paint materials. Our studies suggest that LMWC from H. illucens is a promising material that can expand the range of antiseptics used in painting. Graphical Abstract

Introduction. The operation of eco friendly and high-efficiency internal combustion engines is not possible without deep and comprehensive study of using new types of fuels. That is why, forecasting the indicators of injecting and spraying in a diesel engine running on a mixed alcohol-containing fuel, which have a direct effect on the combustion and formation of toxic components and, as a result, on efficiency and eco friendliness, is an urgent scientific task. Aim of the Study. The study is aimed at developing a theoretical basis for calculating the characteristics of injecting and spraying methanol-containing fuel into diesel engine cylinders that allows optimizing its processes. Materials and Methods. There are considered the characteristics of injecting and spraying alcohol-containing fuel in a diesel engine modified to operate on a mixed methanol-containing fuel. There were used the well-known A.S. Lyshevsky dependencies, which fairly reliably reflect the processes of injecting and spraying in diesel engines. Results. The in-depth studies of the basic principles for evaluating the indicators of injecting and spraying standard fuel made it possible to adapt them for fuels of mixed methanol-containing composition and to investigate the dynamics of changes in the duration and speed of injection, the Weber criterion values, the boundaries between the areas of fuel jet forming, droplet size and spraying angle. Discussion and Conclusion. There has been developed a theoretical basis for calcu­lating the characteristics of injecting and spraying methanol-containing fuel that makes it possible to optimize the operation of a diesel engine running on mixed fuel and, as a result, improve its efficiency and eco friendliness. The presented numerically information on the change in the boundaries of the fuel jet forming areas, the size of the droplets and the angle of the spraying cone allows us to reliably determine the basic parameters of spraying of the used mixed methanol-containing fuels, determine the vector of optimization of the mixing processes and gives insight into the promising directions in designing the geometry of combustion chambers, intake ducts, etc.

The paper considers the possibility of using the diamond-silicon carbide composite Skeleton® with a technological coating of polycrystalline silicon as a substrate for X-ray mirrors used with powerful synchrotron radiation sources (third+ and fourth generation). Samples were studied after polishing to provide the following surface parameters: root-mean-square flatness ≃ 50 nm, micro-roughness on the frame 2 µm × 2 µm σ ≃ 0.15 nm. The heat capacity, thermal conductivity and coefficient of linear thermal expansion were investigated. For comparison, a monocrystalline silicon sample was studied under the same conditions using the same methods. The value of the coefficient of linear thermal expansion turned out to be higher than that of monocrystalline silicon and amounted to 4.3 × 10−6 K−1, and the values of thermal conductivity (5.0 W cm−1 K−1) and heat capacity (1.2 J K−1 g−1) also exceeded the values for Si. Thermally induced deformations of both Skeleton® and monocrystalline silicon samples under irradiation with a CO2 laser beam have also been experimentally studied. Taking into account the obtained thermophysical constants, the calculation of thermally induced deformation under irradiation with hard (20 keV) X-rays showed almost three times less deformation of the Skeleton® sample than of the monocrystalline silicon sample.

This study focuses on the comparison of aerosol columnar aerosol optical depth (AOD) and lidar ratios together with vertical profiles of aerosol extinction and backscatter at 532 nm retrieved over the King Abdullah University of Science and Technology (KAUST) campus observation site for the period of 2019–2022 using the Generalized Retrieval of Atmosphere and Surface Properties (GRASP) and Micro-Pulse Lidar Network (MPLNET) approaches. An emphasis is placed on independent analysis of daylight and nighttime retrievals to estimate how strongly the differences in the assumptions of both methods made in the absence of nighttime AOD observations influence the retrieval results. Additionally, two aerosol products provided by GRASP excluding and including the volume depolarization observations at 532 nm provided by MPLNET are analyzed to estimate the potential benefits of usage of depolarization data in aerosol profile retrievals. Overall, both columnar and vertical MPLNET and GRASP products demonstrated a better agreement for daytime retrievals for the GRASP product that excluded the depolarization information. At the same time, inclusion of the volume depolarization observations improved the agreement between MPLNET- and GRASP-estimated values at nighttime, both columnar and vertical. In addition, estimated values of daytime extinction profiles at ground level were compared to assess the impact of the assumption of a constant aerosol vertical distribution in the cutoff zone of lidar observations implied in GRASP. The values estimated by GRASP demonstrated a good agreement with MPLNET, for retrievals both including and excluding volume depolarization information. A seasonal variability in the diurnal cycle of aerosol properties estimated by GRASP over the KAUST site for the period 2019–2022 is presented, analyzed and discussed.

The work is dedicated to the synthesis and investigation of Ni-containing catalysts based on glass-fiber carriers (GFC) with an additionally deposited secondary layer of porous SiO2 for the process of carbon dioxide methanation. Ni-based GFCs were prepared using the surface thermosynthesis (STS) and pulse surface thermosynthesis (PSTS) methods, involves heat treatment of the catalyst with the supported Ni precursor at a high heating rate; such procedure was not applied earlier for production of CO2 methanation catalysts. The GFC sample prepared by the PSTS method with a fuel additive in the precursor composition is characterized by a more uniform distribution of Ni particles on the catalyst surface and better dispersion of Ni, smaller crystallite size: NiO crystallites in this freshly prepared GFCs are smaller than 10 nm and Ni crystallites in reduced catalysts are