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Magnetic reconnection and current sheet kink instability often develop concurrently in current sheets, yet their dynamic interplay remains unclear. We investigate their interaction in the magnetotail of a 3D global magnetospheric hybrid‐Vlasov simulation. We identify the instability growth and saturation phase and estimate the evolution of the reconnection rate during the same interval. Our findings indicate that the reconnection rate decreases during the instability growth phase, especially at locations where the current sheet undergoes significant perturbations. These results highlight the intricate three‐dimensional relationship between reconnection and kink instabilities, suggesting that the kink instability plays a significant role in modulating the reconnection rate. Plain Language Summary Magnetic reconnection is a fundamental process in plasmas during which magnetic field energy is transferred, often explosively, to plasma particles. Magnetic reconnection develops in current sheets—extended regions of enhanced electric currents that are ubiquitous in plasmas. Current sheets are also the natural seedbed of plasma instabilities leading to wave generation. Among plasma instabilities, the current sheet kink instability causes the current sheet to distort and bend. Kink‐like distortions of the current sheet have been observed in a variety of plasmas, notably in the Earth's magnetotail (the region extending on the night side of the Earth's magnetosphere). While the kink instability and magnetic reconnection occur together in current sheets such as the magnetotail, their interaction is not well understood. We use a numerical simulation modeling the whole Earth's magnetosphere to investigate the interaction of the two processes in three dimensions. We find that as the kink waves grow, magnetic reconnection slows down, especially at locations where the current sheet is highly disturbed. Our findings suggest that the kink instability significantly affects magnetic reconnection. This study provides a deeper understanding of the intricate relationship between these two important phenomena. Key Points We investigate the interaction of magnetic reconnection and kink instability in a 3D global hybrid‐Vlasov simulation of near‐Earth space Magnetic reconnection is ongoing in the Earth's magnetotail during the growth and saturation phases of the kink instability The reconnection rate decreases during the instability growth phase, especially where the current sheet undergoes significant perturbation

Flux transfer events (FTEs) are transient magnetic flux ropes at Earth's dayside magnetopause formed due to magnetic reconnection. As they move across the magnetopause surface, they can generate disturbances in the ultralow frequency (ULF) range, which then propagate into the magnetosphere. This study provides evidence of ULF waves in the Pc2 wave frequency range (>0.1 Hz) caused by FTEs during dayside reconnection using a global 3D hybrid‐Vlasov simulation (Vlasiator). These waves resulted from FTE formation and propagation at the magnetopause are particularly associated with large, rapidly moving FTEs. The wave power is stronger in the morning than afternoon, showing local time asymmetry. In the pre and postnoon equatorial regions, significant poloidal and toroidal components are present alongside the compressional component. The noon sector, with fewer FTEs, has lower wave power and limited magnetospheric propagation. Plain Language Summary The Earth's magnetosphere is a dynamic region shaped by the interplay between the solar wind and Earth's magnetic field. This interaction occurs at the boundary of the magnetosphere (magnetopause) through a process known as magnetic reconnection, giving rise to Flux Transfer Events (FTEs), which are magnetic structures that carry flux and energy into the magnetosphere. These FTEs form either in sudden bursts, patchy patterns or in a continuous, and relatively stable way making the magnetopause surface dynamic. As the FTEs move along the boundary of the magnetosphere, they create compressed regions and lead to wave generation that can extend into the magnetosphere. The study uses an advanced 3D hybrid‐Vlasov simulation model to analyze waves originated from FTE formation and propagation at the magnetopause. We find that rapidly moving and large FTEs have a significant impact on the magnetopause, leading to the generation of ULF waves with frequency above 0.1 Hz. This shows first direct evidence supporting previous theoretical speculations regarding the ability of FTEs to generate waves near the magnetopause. Key Points Dayside Pc2 waves (>0.1 Hz) have been detected in a 3D hybrid‐Vlasov simulation These waves exhibit lower intensity within the magnetosphere at noon, compared to the prenoon and postnoon sectors Pc2 waves observed in the simulation are associated with largest and fast moving flux transfer events initiated by subsolar reconnection

A study of the interactions of porcine pancreatic lipase (PPL) with chitosan is the most interesting and important in order to regulate the enzymatic properties of the future nanomaterials based on these biopolymers. A decrease in catalytic activity of pure PPL towards triacetin during prolonged operation and storage is shown: activity decreases by 24.1% within 1 hour and by 54.0% - in the case of the lipase storage in solution for 1 month. The optimum temperature of 40°C was determined for samples of pure PPL, whereas a small shift from 40° to about 45°C - for PPL:Chit complex (50:1). The catalytic activity of free PPL at 40°C was the highest (as compared to lower and higher temperatures) and stable for 20 min. However, the dynamics showed a pronounced decrease to almost 2 times within further 30-60 minutes. In contrast, at 40°C the catalytic activity of PPL in complex with chitosan (50:1) stabilized at almost the same level (although it was lower than the activity of free PPL in the first 30 minutes of measurement). The PPL:Chit complex can be considered as promising catalytic nanomaterials (based on chitosan and lipase) for further applications.

Introduction. At the present stage of industrial development, the electromagnetic field is widely used in various technological processes. The force effect of an electromagnetic field on conductive materials is used in a class of technological operations called electromagnetic forming. Problem. Under the conditions of electromagnetic forming, the main element of the technological equipment – the inductor – is simultaneously subjected to the force impact with the workpiece. At certain levels of the electromagnetic field, the deformation of the inductor becomes so significant that it can lead to a loss of its efficiency. Goal. Computational analysis of a thin-walled curved workpiece and a two-turn inductor under the conditions of electromagnetic processing of the workpiece corner zone. Determining the distribution of quantitative characteristics of the electromagnetic field and the stress-strain state and conducting assessments based on them regarding the efficiency of the technological operation. Methodology. Computational modeling using the finite element method as a method of numerical analysis. The results on the distribution of quantitative characteristics of the electromagnetic field and components of the stress-strain state for a thin-walled workpiece and an inductor are obtained. It is shown that for the specified characteristics of the technological operation, the inductor remains operational, and plastic deformations occur in the workpiece. A series of calculations were carried out, in which some parameters of the technological system were varied. Originality. For the first time, the results of the calculation analysis of the quantitative characteristics distribution of the electromagnetic field of the deformation process for the «inductor – thin-walled curved workpiece» system are presented. Practical value. The presented design scheme of a curved thin-walled workpiece and a two-turn inductor, the method of calculation analysis and some obtained results can be used in the analysis of electromagnetic processing of thin-walled structures that contain curved elements.

Quantum dots (QDs) are widely used as biomarkers that has both fundamental and applied importance. Since cell membranes are mainly composed of lipids such as phosphatidylcholine (PC) and its derivatives, it is important to investigate the interaction of QDs with PC in monolayers to understand the penetration mechanism. This work is devoted to the study of the interaction of QDs with PC by determining their surface-active properties at various interfaces by dynamic surface tension. The isotherms of the surface tension of 5 μg/L QDs solution or 0.17 mM (0.86 mM) PC solutions, as well as the solutions of the mixtures of QDs and PC: 0.17 mM (0.86 mM) PC and 5 μg/L QDs or 0.17 mM (0.86 mM) PC and 15 μg/L QDs were obtained. The mixed QDs/PC monolayers (at low content of QDs equal to 1:100) were characterized by the formation of a stable domain structures. An adsorption of PC at QDs allows to vary the degree of surface modification by changing the amount of the lipid. Such nanoparticles have dimensions not very different from the sizes of the initial QDs, due to the small size of lipids and are well suited for incorporation into biomembrane models.

Introduction. The electromagnetic field is an integral attribute of the operation of many technical and technological systems. The action of an electromagnetic field leads to deformation, a change in temperature, a change in the physical properties of the materials. Problem. High-intensity electromagnetic fields can cause such a strong deformation of conductive bodies that it can lead to irreversible shape change or destruction. This fact is used in a class of technological operations: electromagnetic forming. Here, both the workpiece and the equipment are subjected to intense force action. As a result, equipment elements may become inoperable. Goal. Creation of a computational analysis method of the electromagnetic field propagation in systems of conductive bodies and subsequent analysis of deformation. Application of this method to the study of processes in electromagnetic forming systems in order to determine rational operational parameters that provide the result of a technological operation. Methodology. A variational formulation of the problems of an electromagnetic field propagation and deformation of conductive bodies systems is used. Numerical modeling and analysis are performed using the finite element method. Results. In a general form, a system of resolving equations for the values of the vector magnetic potential and displacements is obtained. The influence of the electromagnetic field is taken into account by introducing electromagnetic forces. The results of calculations for a technological system designed for electromagnetic forming of curved thin-walled workpieces are presented. Originality. For the first time, a method of computational analysis is presented, which involves modeling within the framework of one design scheme both the process of electromagnetic field propagation and the process of deformation. Practical significance. The proposed method of computational analysis can be used for various technological systems of electromagnetic forming in order to determine the rational parameters that ensure both the operability of the equipment and the purpose of the technological operation - the necessary shaping of the workpiece.

Immobilization of enzymes (IoE) from animal origin on natural carriers increases the system stability; facilitates the separation and accelerates the recovery of the enzyme; makes reuse possible; provides a significant reduction in operating costs. There are numerous IoE methods and systems, including immobilization of various lipases on major carbohydrate biopolymers (chitin, chitosan, cellulose, etc.), discussed in this review. The key points of the most encouraging methods “for increasing the activity and stability” of such biopolymer systems are the “chitosan particle activation” by “ultra-sonication” and multiplicative “addition of glutaraldehyde” to these abovementioned systems. The design of such complex biopolymer preparations (in their various forms) is an important area of modern agrosciences, biomedicine, veterinary, zootechnology and bionanotechnology.

In the paper showing that one of the main way for Ukraine electric power industry evolution is electric power networks and systems improvement and construction considering Smart Grid concept. The main idea of Smart grid is the reliable, energy-efficient and high-quality energy supply system. To implement the idea, it is necessary to create a high-performance information and computing infrastructure. The main components of Smart Grid is emergency mode diagnostics and damage monitoring. Providing fault diagnostics and fault monitoring can improve the power supply reliability and quality to consumers. So, the task of quickly and accurately determining the place of damage is important. In the article showing that emergency detection tools in sections of both cable and overhead electrical networks it’s a way to improve efficiency of the networks. The diagram of the placement of damage indicators on the section of the electrical distribution network is presented, which allows determining the direction of the search for the location of the damage. A comparative analysis of measuring current transformers of optical and electromagnetic type was carried out. It is shown that a significant number of advantages of optical measuring current transformers, which can be used in damage indicators, can be provided by measuring current transformers of the electromagnetic type. Creating fault indicator based on the Smart Grid concept lets do to reduce searching time for the cause and location of an emergency situation to a minimum. In this concept application fault indicator in energy grid ensure it connection to operating overhead and cable lines without removing voltage by connecting the output of the secondary winding of the measuring current transformer of the detachable design to the measuring converters directly placed near the current measuring transformers with the help of a mechanical spring fastener. A block diagram of a specialized information-measuring system with a damage indicator was created, taking into account the requirements of the Smart Grid concept, which allows to reduce the time of searching for the cause to a minimum.

In the paper showing A U-Net-type convolutional neural network proposed for vegetation segmentation in multispectral imagery. The architecture of this network has modified and expanded to achieve better results with a smaller training dataset. The use of the network has made it possible to improve the solution to the problem of accurately identifying objects from the background based on existing information without the use of additional means of obtaining data. The processing of images of a corresponding nature is shown for 4-channel multispectral satellite images using a U-Net-shaped network trained on aerial images. Preprocessing showed the need to take into account the image formation model and perform post-training of the network based on the obtained data. A comparison conducted between the results of vegetation zone delineation in multispectral images using a convolutional neural network with a modified U-Net-like architecture and the Normalized Difference Vegetation Index (NDVI). The NDVI vegetation index uses data from various spectral channels and calculated as the ratio between intensities in the red and near-infrared channels of multispectral imagery, displayed as a number from -1 to +1, where a higher index value signifies denser green vegetation. Shown that for acceptable results, it is enough to use 4-channel images (NIR+RGB). The simulation performed in the MATLAB system.

The article discusses a method for assessing the innovativeness of an enterprise in digital economy, based on the collection of information according to the certain assessment criteria, and also includes a developed mathematical apparatus for calculating the integral index of innovativeness. The article proposes an “Entry-Exit” assessment model.