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Abstract Alzheimer’s disease (AD) is a debilitating neurodegenerative disorder characterized by brain aggregation of β-amyloid (Aβ) peptides and phosphorylated tau (P-tau) proteins. Extracellular vesicles (EVs) can be isolated and studied for potential roles in disease. While several studies have tested plasma-derived EVs in AD, few have analyzed EVs from cerebrospinal fluid (CSF), which are potentially more closely related to brain changes. This study included 20 AD patients and 20 cognitively unimpaired (CU) participants. Using a novel EV isolation method based on acoustic trapping, we isolated and purified EVs from minimal CSF volumes. EVs were lysed and analyzed by immunoassays for P-tau217 and P-tau181. Isolation was confirmed through transmission electron microscopy and the presence of EV-specific markers (CD9, CD63, CD81, ATP1A3). Nanoparticle tracking analysis revealed a high variance in EV distribution. AD patients exhibited increased P-tau181 and decreased P-tau217 in EVs, leading to a higher EV P-tau181/P-tau217 ratio compared to CU. No significant differences in EV counts or sizes were observed between AD and CU groups. This study is the first to use acoustic trapping to isolate EVs from CSF and demonstrates differential P-tau content in AD-derived EVs, warranting further research to understand the relationship between these EV changes and brain pathology.

The conductive properties of CNT/polymer composites have been extensively studied. However, the impact of CNT distribution in the matrix on the composite polarization remains underexplored and poorly understood. Since it is difficult to achieve a uniform distribution of CNTs in polymers, most researchers have focused only on indiscriminately aggregated states. In this article, a new blending method was suggested to prepare a series of epoxy resin-based composite samples with varying levels of CNT uniformity/aggregation and the same filling fractions. Notably, the permittivity values turned out to be inversely related to the composite uniformity: the lowest permittivity values were obtained in the most uniform formulation, and vice versa. With 0.1% CNT, the real part values of the most uniform and aggregated samples were 6.6 and 16.2 at 107 Hz and 11.6 and 370.5 at 101 Hz, respectively. For the filler content of 0.1–0.5%, the conductive properties were largely determined by the distribution of CNTs and not their content. Within the entire frequency range, the uniform sample with 0.2% CNT exhibited significantly lower permittivity than the aggregated sample with 0.1% CNT. These findings emphasize the importance of the aggregation factor and underscore the non-universality and limitations of the percolation theory and power laws. The observed phenomenon is best explained by the micro-capacitor model, or the Maxwell–Wagner polarization, and suggests that a significant portion of the literature in the field needs to be reconsidered.

Currently, the commissioning of power plants based on renewable energy sources (RES) using inverters is becoming widespread. However, these power plants do not participate in maintaining the stability of the power system during emergency disturbances, since they are switched off by technological protections when a disturbance occurs. In the future, when power plants based on renewable energy sources become widespread, ensuring the possibility of their participation in maintaining sustainability will significantly increase the reliability of the energy system. A preliminary assessment of the effectiveness of participation in maintaining sustainability should be carried out through computer modeling.THE PURPOSE: To realize the possibility of participation of RES-based power plants in ensuring reliable and sustainable operation of the power system, as well as to realize the possibility of performing a preliminary assessment of the effectiveness of the proposed method.METHODS. In this paper, the application of virtual synchronous generator technology is proposed to realize the possibility of participation of RES-based power plants in ensuring the reliability and sustainability of the power system. Also, a method of modeling the virtual synchronous generator in Matlab software package is proposed.RESULTS. The technology of virtual synchronous generator is proposed, which with the use of inverter, electric energy storage and appropriate control system can provide the increase of dynamic stability of power system. A method of modeling the virtual synchronous generator in Matlab software package is proposed. The results obtained allow us to conclude that the constructed model of a virtual synchronous generator is efficient, maintains the stability of the system and ensures correct control of the inverter, as a result of which the parameters of the electrical network are maintained within acceptable limits. The resulting computer model can be used in further research.CONCLUSION. The technology of virtual synchronous generator allows to imitate in the inverter the inertial and damping characteristics of the traditional synchronous generator, and the proposed computer model will help to evaluate the effectiveness of this technology when implemented in the power system.

The majority of reserves of small oil companies of the Republic of Tatarstan are represented by carbonate reservoirs with low filtration and capacitance properties, low reservoir pressures and high oil viscosity. All this leads to a rapid decrease and a low level of current oil flows. The Akan oil field of Predpriyatie Kara Altyn CJSC is one of the examples. Thermal methods are considered as the most effective technologies for deposits with high-viscosity oil. According to the results of laboratory study of various variants of thermal methods and geological and hydrodynamic modeling, the steam-cyclic method of development was determined as the most effective at the Akan field. Two producing directional wells and two horizontal wells have been selected for experimental work on steam injection. The article considers the downhole equipment used for injection heat carrier, describes the process of steam injection with the dynamics of controlled parameters, production indicators and efficiency after heat treatment of wells. Conclusions are presented for the completed works on wells.

The article deals with arrowheads from sites of the Piany Bor culture with various marks applied to the items in the process of manufacture and use. In the course of work with museum collections, we managed to identify 38 arrowheads with marks, which come from 15 burials of Piany Bor burial grounds and one settlement monument. The purpose of markings can be different: from casual to purposeful. The analysis has shown that some of the marks are only traces of marking of the material during the manufacture of the item, the other part can be specially applied signs in the process of manufacture or while using. There is no reason to consider the marks as elements of writing systems. Chronologically the considered finds correspond to the I century BC – II century AD. The spread of marks on arrowheads from Piany Bor sites is probably an epochal phenomenon characteristic of the Middle Sarmatian time. The marks are not a direct copying and exact borrowing, but a reworking of the idea of marking of objects, using their own traditions of inscription of marks.

The article publishes preliminary results of archaeological research on mound No. 45, the Bustanaevsky burial mound, located on the territory of the Buraevsky district of the Republic of Bashkortostan. The monument was discovered in 2011, archaeological research began in 2015 under the leadership of A.G. Kolonskikh. Currently, excavations of the necropolis continue in the course of joint research by the Institute of Ethnological Research named after. R.G. Kuzeev and the Institute of Archaeology named after A. Kh. Khalikov Tatarstan Academy of Sciences. During excavations, one single burial was discovered under the mound. Along with the poorly preserved skeleton, the burial contained archaeological material represented by two vessels, arrowheads and elements of a belt set made in the heraldic style, horse bones and iron bits. The data obtained allow us to assume that the necropolis was left by the bearers of the Kushnarenkovo archaeological culture. The preliminary dating of the burial is the end of the 6th - beginning of the 7th century AD.

In 2023, the research activities of the Institute of Archaeology named after A.Kh. Khalikov of the Tatarstan Academy of Sciences were carried out in three scientific fields. In 2023 the work on preparation and publication of the collective monograph "Archaeology of the Volga-Urals" in 7 volumes was completed. As part of the implementation of the state program of the Republic of Tatarstan, comprehensive scientific and safety and rescue studies were conducted in the regions of the Russian Federation, as well as in Mongolia, Kyrgyzstan and Uzbekistan. The formation of an information geographic system has been continued. The work with collections of the Museum of Archaeology of the Republic of Tatarstan is being successfully carried out. An important part of the Institute's activity is the training of highly qualified personnel under postgraduate programs with further defense of theses, advanced training within the international archaeological schools. The Institute carries out expert international activities on the inclusion of archaeological sites in the UNESCO World Cultural Heritage List, in particular such archaeological heritage sites as Denisova Cave (Altai region), Tanais (Rostov region).

Abstract The Bitcoin market has experienced unprecedented growth, attracting financial traders seeking to capitalize on its potential. As the most widely recognized digital currency, Bitcoin holds a crucial position in the global financial landscape, shaping the overall cryptocurrency ecosystem and driving innovation in financial technology. Despite the use of technical analysis and machine learning, devising successful Bitcoin trading strategies remains a challenge. Recently, deep reinforcement learning algorithms have shown promise in tackling complex problems, including profitable trading strategy development. However, existing studies have not adequately addressed the simultaneous consideration of three critical factors: gaining high profits, lowering the level of risk, and maintaining a high number of active trades. In this study, we propose a multi-level deep Q-network (M-DQN) that leverages historical Bitcoin price data and Twitter sentiment analysis. In addition, an innovative preprocessing pipeline is introduced to extract valuable insights from the data, which are then input into the M-DQN model. A novel reward function is further developed to encourage the M-DQN model to focus on these three factors, thereby filling the gap left by previous studies. By integrating the proposed preprocessing technique with the novel reward function and DQN, we aim to optimize trading decisions in the Bitcoin market. In the experiments, this integration led to a noteworthy 29.93% increase in investment value from the initial amount and a Sharpe Ratio in excess of 2.7 in measuring risk-adjusted return. This performance significantly surpasses that of the state-of-the-art studies aiming to develop an efficient Bitcoin trading strategy. Therefore, the proposed method makes a valuable contribution to the field of Bitcoin trading and financial technology.

Background. Improving pediatric observation globally and in Kyrgyzstan is essential for early detection of developmental issues and monitoring normal physical parameters. The purpose of the study was to investigate the indicators of bone composition in children of Kyrgyz nationality of both sexes in the early childhood period. Materials and methods. To achieve the goal, 800 children from 4 to 7 years old were examined using anatomical-anthropometric and bioimpedance methods. Results. It was revealed that the absolute content of bone component in male respondents at the age of 4 years ranges from 3.24 to 5.17 (4.10 ± 0.01) kg, 5 years — from 3.27 to 5.81 (4.26 ± 0.01) kg, 6 years — from 3.34 to 5.87 (4.39 ± 0.01) kg and 7 years — from 3.23 up to 6.02 (4.59 ± 0.01) kg. The absolute index of the bone component in 4-year-old girls has an individual variability of 3.04–5.17 (3.97 ± 0.01) kg, 5-year-old — 3.27–5.61 (4.20 ± 0.01) kg, 6-year-old — 3.34–5.77 (4.34 ± 0.01) kg and 7-year-old — 3.43–6.02 (4.40 ± 0.01) kg. Conclusions. The highest bone content was found in individuals with muscular somatotype, while the lowest values were in asthenoid and thoracic somatotypes for both males and females. Boys had higher bone component index at ages of 4 and 7.

Generating a realistic three-dimensional model of the human body is a very time-consuming task. Even with the necessary computing resources, generation errors occur on the figures of people who differ from the average physique. In this paper, an experimental algorithm for reading anthropometric data from only two full-face and profile photographs is proposed. The proposed solution to the problem of generation using the selection of anthropometric points involves setting the constraints of the SMPL (Skinned Multi-Person Linear Model) model. For segmentation of the human body based on empirical studies, a modification of the Fully Connected Convolutional Neural Network (FCN) ResNet101, trained on the COCO Segmentation 2017 dataset, was used. With its help, the basis for the detection of anthropometric points in full-face and profile photos was obtained. The error in determining anthropometric points ranges from 2 to 5 % depending on their location. The constraints for the SMPL rendering model are calculated using the Levenberg- Marquardt algorithm. For its correct operation, a special cost function is proposed, taking into account the features of this task. The dataset collected by the authors of the article (117 people of different physiques and height) shows that the proposed method allows you to obtain a small average absolute error (MAE = 0.0395 m) and a high coefficient of determination (R2 = 0.913). The graph of anthropometric points sets stricter conditions for generating a figure and any deviation from the graph is a consequence of a large generation error. The proposed solution allows you to accurately generate a model of the human body. At the same time, low requirements for computing resources and the quality of users’ initial photos remain. The proposed solution can be used in online fitting rooms, which adds additional complexity to the task due to the requirements to restore the figure from only two pictures as well as the need to accurately reproduce the features of male and female figures.

Aiming at the increasing demand for electric energy in aircraft in the future, a multi-objective optimization aircraft engine constrained model predictive control method based on generation power distribution is proposed. Firstly, based on the aircraft engine component level model and the equilibrium manifold theory, the aircraft engine equilibrium manifold expansion model is established. Secondly, the influence of the power generation is modeled, and the influence of the low- and high-pressure shaft generators on the normal operation of the aircraft engine is studied and compared. The control variables such as fuel flow and total generation power are taken as the constraint conditions to design the constraint model predictive controller. Furthermore, the multi-objective grey wolf optimization algorithm is introduced to intelligently optimize the parameters of the designed controller. At last, the simulation based on the component level model shows that the high-pressure shaft generator has less influence on the state quantity, including engine thrust, than the low-pressure shaft generator. The proposed control method using the multi-objective gray wolf optimization (MOGWO) algorithm has rapid response and no steady-state error.

The lands of the forest fund on the territory of the steppe Don region are distinguished by a significant spread over the area of the main melliferous plant Robinia pseudoacacia (R. Pseudoacaci L.), which has a high bioresource potential for the honey collection of the Rostov region. The objectives of the research included identifying the features of the honey productivity of R. pseudoacacia plantations, depending on the dynamics of taxation indicators and forest conditions in the steppe Don region. In order to study changes in the honey productivity of Robinia plantations, accounting work was carried out in pure and mixed stands in each age group. The relationship of the studied indicator of Robinia forest stand with taxation characteristics and growing conditions was revealed. The highest honey productivity (347.5 kg/ha) is observed in pure Robinia forest stands in the forest growing conditions of fresh glague - sedge oak groves, where at the age of 50 there is an intensive flowering of trees (80.060 thousand pieces) and active release of sugar in nectar (2.48 mg). According to the observations, the density of the forest stand decreases with age, and the number of flowers on the trees increases. The results of the research showed that at the age of 40 years, the honey productivity of a hectare of Robin plantations reaches its maximum (586.3 kg/ha). The equations for the dependence of honey productivity on the taxation characteristics of R. pseudoacacia plantations and the obtained high correlation coefficients indicate a close relationship between the studied indicators. The data obtained will make it possible in the future to calculate the honey productivity of Robinia forest stands more accurately, taking into account the dynamics of their taxation indicators.

The authors consider the materials of the excavations by S.E. Zubov, carried out on the Kipchakovo hillfort in 2006. Set of artifacts and numerous surface finds from excavations obtained on the territory of the hillfort under the plough allow to conclude that it belongs to the early stage of the Piany Bor culture and unite it with the synchronous Kipchakovo I barrow – subsoil burial ground into one archaeological assemblage. These objects of archaeology demonstrate the complex ethnic and cultural processes of the Piany Bor culture formation, complicated by the migrations of the population. It is concluded that the fortified settlement is single-layered and chronologically connected with the burial ground and their functioning can be determined by time within the II century BC – I century AD. The sizeable area of the hillfort (40 000 m2) in comparison with other Piany Bor fortified settlements and the large size of the burial ground make it possible to suppose that the Kipchakovo hillfort was an administrative and territorial center of the big importance at the turn of the era. Taking into account the small number of archaeological works carried out on the Piany Bor culture settlements in general and the uniqueness of the Kipchakovo archaeological site in particular, the authors consider it reasonable to publish the study of this new archaeological site, the materials of which significantly supplement the picture of the historical and cultural development of the region in the Early Iron Age.

With the change in the social role of horses and the development of veterinary medicine, their average life expectancy has increased, so the problem of the quality of life of geriatric horses has become relevant nowadays. The purpose of the study is to determine the main approaches to the assessment of the quality of life of horses in old age. The study employed the following methods: analysis, synthesis, comparison, graphical presentation of data. Five main ways to improve life expectancy and QoL indicators and reduce mortality of old horses were determined: full and sufficient feeding; ensuring optimal ADL performance; creation of comfortable housing conditions; conducting cryotherapy maintenance vibrotherapy, manual therapy, horseshoe therapy, therapeutic and preventive exercises, magnetotherapy, phototherapy, shock wave and ultrasound therapy; use of modern methods of early detection and treatment of oncological diseases. It was found that the most common causes of death were diseases of the gastrointestinal tract, followed by diseases of the musculoskeletal system and reproductive system, and oncological diseases. Among the latter, tumours of the pituitary and thyroid glands, melanoma, sarcoidosis, lymphoma, squamous cell carcinoma (SCC) prevailed – up to 60% of oncological sick horses. It was summarised that quality of life assessments, including evaluation of factors related to health, activities of daily living and mental well-being, are useful in informing decisions regarding management, health care and euthanasia. The results of this study can be used by equestrian professionals, farmers or veterinarians to help them choose the safest and most beneficial care for horses

The Institute of Archaeology named after A.Kh. Khalikov of the Tatarstan Academy of Sciences has been actively cooperating with scientific centres and universities of the Republic of Uzbekistan since 2022. One of the fields of cooperation is the implementation of the scientific and educational project "Bolgar International Archaeological School". The support of the International Institute for Central Asian Studies (Samarkand, Uzbekistan) and the successful implementation of the scientific and educational project served as the beginning of closer and fruitful cooperation. In March 2023, jointly with Termez State University, an interdisciplinary study of the archaeological heritage site "Palace of Termezshahs", dating from the XI–XII centuries, was carried out. In May-June 2023, archaeological studies were conducted together with the Nukus State Pedagogical Institute named after Ajiniyaz on the Khaivan-Kala fortified settlement of the VII–X centuries. Within the scientific and educational cooperation at Termez State University, specialists of the Institute of Archaeology named after A.Kh. Khalikov RT implemented an additional professional training programme "Geoinformation technologies and non-destructive methods".