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This investigation quantifies the activity concentrations of natural radionuclides (226Ra, 232Th, and 40K) in the soils and certain rocks of the Koytash–Ugam Range, Uzbekistan, and assesses their radiological risks. Gamma-spectrometric analysis of soil and rock samples revealed activity concentrations ranging from 456.2 ± 56.0 to 813.9 ± 76.0 Bq kg−1 for 40K, 18.2 ± 6.3 to 70.0 ± 12.0 Bq kg−1 for 226Ra, and 30.1 ± 2.9 to 57.9 ± 10 Bq kg−1 for 232Th. This data indicates a heterogeneous distribution of radionuclides, informing radiation safety and health risk assessments on a global scale. The calculation of radiological hazard indices, including the alpha-index (ranging from 0.09 to 0.35), gamma-index (ranging from 0.40 to 0.73), and both internal (ranging from 0.40 to 0.54) and external (ranging from 0.36 to 0.54) hazard indices, was undertaken to ascertain potential health risks. The radium equivalent activity ranged from 108.4 to 199.3 Bq kg−1, and the absorbed dose rates were 51.0–93.3 nGy h−1 indoors and 96.6–178.2 nGy h−1 outdoors. These metrics underlie the estimated annual effective dose of 536.5–988.5 × 10−3 mSv y−1, highlighting the variability in radiation exposure. Additionally, the potential lifetime cancer risk was projected at 1770.4 to 3262.0 per million, with an annual gonadal dose equivalent of 361.9 to 655.5 μSv y−1, reflecting natural background radiation influence. The results underscore the importance of safe material use in construction and the necessity for routine natural radioactivity monitoring. Radon flux density (RFD) values within acceptable construction limits (26–176 mBq m−2 s−1) suggest the area's suitability for development, considering recommended safety guidelines. This study not only aids local environmental and public health frameworks but also enriches the international knowledge base, facilitating comparative studies for the advancement of global radiation protection standards. Through a detailed examination of radionuclide distribution in an under-researched area, our research highlights the critical need for integrated international approaches to natural radiological hazard assessment. [ABSTRACT FROM AUTHOR]

Uzbekistan (Central Asia) is experiencing serious water stress as a consequence of altered climate regime, past over-exploitation, and dependence from neighboring countries for water supply. The Chirchik–Akhangaran drainage basin, in the Tashkent province of Uzbekistan, includes watersheds from the Middle Tien Shan Mountains escarpments and the downstream floodplain of the Chirchik and Akhangaran rivers, major tributaries of the Syrdarya river. Water in the Chirchik–Akhangaran basin is facing potential anthropogenic pressure from different sources at the scale of river reaches, from both industrial and agricultural activities. In this study, the major and trace element chemistry of surface water and groundwater from the Chirchik–Akhangaran basin were investigated, with the aim of addressing the geogenic and anthropogenic contributions to the dissolved load. The results indicate that the geochemistry of water from the upstream catchments reflects the weathering of exposed lithologies. A significant increase in Na+, K+, SO42−, Cl−, and NO3− was observed downstream, indicating loadings from fertilizers used in croplands. However, quality parameters suggest that waters are generally suitable for irrigation purposes, even if the total dissolved solid indicates a possible salinity hazard. The concentration of trace elements (including potentially toxic elements) was lower than the thresholds set for water quality by different regulations. However, an exceedingly high concentration of Zn, Mo, Sb, Pb, Ni, U, As, and B compared with the average river water worldwide was observed. Water in a coal fly-ash large pond related to the Angren coal-fired power plants stands out for the high As, Al, B, Mo, and Sb concentration, having a groundwater contamination potential during infiltration. Spring waters used for drinking purposes meet the World Health Organization and the Republic of Uzbekistan quality standards. However, a surveillance of such drinking-water supplies is suggested. The obtained results are indicators for an improved water resource management. [ABSTRACT FROM AUTHOR]

This is the first study providing an up-to-date account of the alien flora in Uzbekistan and analyzing the relationship between the invasion status (casual, naturalized, invasive) of alien plants in this country and their life histories, regions of origin, and habitat affiliations. The data were collected from literature, herbaria, and field surveys. The checklist includes 252 species, of which 44 are invasive (17.5%), 177 naturalized non-invasive (70.2%, giving 220 naturalized species in total), and 31 casual aliens (12.3%). The family with the highest number of alien species is Asteraceae (53, or 21% of all recorded species), followed by Brassicaceae (21), Poaceae (19), and Solanaceae (15). The most represented genera in the alien flora of Uzbekistan are Amaranthus (8 species), Centaurea, Malva, Solanum, and Vicia (5 each). The majority of the alien flora of Uzbekistan are annuals (138 species, i.e., 57% of the total), followed by perennials (52 species, 21.5%). There are only 13 alien woody species recorded. Invasive species originating from Africa, temperate Asia, and Europe are over-represented, as are naturalized species native to Northern America and Southern America. The majority of species are affiliated with agricultural (204 species) and ruderal habitats (164 species); riparian habitats (68 species) and grasslands (38 species) are also well represented. The pattern of invasions in the country is determined by the interaction of source species pools arriving from native regions, their habitat affiliations, and land use. Our study provides the first step toward science-based management of plant invasions in Uzbekistan. It can support policymakers, authorities, and managers in mitigating the current and future impacts of alien species. [ABSTRACT FROM AUTHOR]

For the first time, the cultivated diversity of microalgae in eroded soils in the northern part of the Fergana Valley in Uzbekistan has been studied based on both morphological and molecular genetic analysis. Ten strains of green microalgae (Chlorophyta) and one charophyte strain (Charophyta) were revealed. Only seven strains could be identified at the species level: Chlorella vulgaris, Chromochloris zofingiensis, Deuterostichococcus epilithicus, Pseudomuriella schumacherensis, and Pseudostichococcus monallantoides. Another four strains were identified only at the genus level and require further study: Bracteacoccus sp., Chlorosarcinopsis sp., Klebsormidium sp., and Tetratostichococcus sp. The low species diversity in the microalgae is likely due to both the low fertility of the eroded soils on the slopes, and the limitations of the culture-based approach that only reveals a fraction of the overall microbial diversity. Microalgal colonization of eroded soils in the arid foothill zone can be facilitated by various adaptations, such as small cell size and the production of extracellular polysaccharides, mycosporine-like aminoacids, and secondary carotenoids. The present work may contribute to the further development of highly functional microalgal consortia, which can lead to improvements and sustainable development of low-productivity, arid, and degraded terrestrial ecosystems. [ABSTRACT FROM AUTHOR]

Purpose: Intramural metastasis (IM) is a poor prognostic factor for patients with esophageal squamous cell carcinoma (ESCC). We conducted this study to assess the prognostic impact of IM in an Uzbekistan cohort and to identify the factors associated with the poor prognosis of patients with ESCC and IM. Methods: The subjects of this retrospective analysis were 1083 patients with thoracic ESCC, who underwent curative esophagectomy between 2001 and 2021 at the National Cancer Center of Uzbekistan. We compared the clinicopathological characteristics and survival outcomes of patients with versus those without IM and evaluated the factors associated with the poor prognosis of patients with IM. Results: Patients with pathological IM (n = 59, 5.4%) were significantly older, had a higher percentage of lymphatic invasion and worse pathological N stage, and had shorter overall survival (OS) than patients without IM. Multivariable analysis of OS identified multiple IMs as the only independent prognostic factor in patients with IM (hazard ratio, 6.04; 95% confidence interval, 2.77–13.18; P < 0.001). Patients with multiple IMs had shorter OS and recurrence-free survival than those with a single IM. Conclusion: IM was a poor prognostic factor for patients with ESCC in this Uzbekistan cohort and multiple IMs were associated with worse outcomes. [ABSTRACT FROM AUTHOR]

The study, conducted in higher education institutions in Kazakhstan, Tajikistan, Kyrgyzstan and Uzbekistan, highlights ongoing changes in approaches to education for sustainable development (ESD) in Central Asian countries. This region, exposed to various challenges such as climate change and environmental problems, has recognized the importance and role of education in achieving sustainable development. The study aims to identify the current level of awareness of students and teachers about the Sustainable Development Goals, as well as to understand how universities in the region are integrating ESD principles into their educational programs. The results show that students generally have limited knowledge about the global sustainable development goals, while teachers have a higher level of awareness. Most students receive information about the sustainable development goals (SDGs) through social media and the Internet, while it is less reflected in the curriculum. However, there is a trend towards changing this situation, in particular in Tajikistan, where curricula are becoming more focused on environmental education. Finally, recommendations for universities include integrating ESD principles into teacher development, developing teaching methods and materials, and strengthening collaboration at the regional and international levels to promote sustainable development goals. [ABSTRACT FROM AUTHOR]

This research focuses on the synthesis of novel low-cost granular sorbents based on bentonite clay of the Navbahor deposit, dust fraction of Angren brown coal, and agricultural wastes such as straw and sawdust to meet the internal needs of the Republic of Uzbekistan. The impact of the initial mixture ingredients on the structural and textural properties of bentonite-coal sorbents (BCSs) has been studied using X-ray diffraction, Raman spectroscopy, Fourier-transform infrared spectroscopy, optical microscopy, and nitrogen adsorption-desorption analysis. For determining the sorption capacity of BCSs, a standard model substance methylene blue (MB), was applied. It was revealed that the maximum adsorption amount of MB was 5.3 mg∙g−1 during 2 h of contact. Prolonging the contact time to 24 h allowed for more extensive diffusion of dye molecules into the sorbent's pores, increasing the adsorption capacity to 13 mg∙g−1. It was demonstrated that BCSs could be regenerated by strong oxidizing agents such as sulfuric acid and hydrogen peroxide, with sulfuric acid proving more effective. Regeneration fully restores sorption properties, particularly at low dye concentrations (up to 0.2 mg∙ml−1). Despite slight reductions in adsorption capacity over multiple regeneration cycles, the sorbents maintain their structural integrity and durability. It is shown that compared to imported expensive activated carbon, the gross profitability of the in-house production of such granular BCSs within the territory of Uzbekistan increases from 48 to 78%, while the net income increases almost three times. [ABSTRACT FROM AUTHOR]

Background: The transition to energy-sustainable systems is a globally accepted concept, but it is implemented with various degrees of success around the world. The aim of this paper is to determine the status of green transition in five Central Asian countries (Tajikistan, Turkmenistan, Uzbekistan, Kazakhstan, and the Kyrgyz Republic) that are among the highest energy consumers globally and the most vulnerable to climate change. Despite a notable improvement in living conditions across all countries over the past two decades, the region remains underdeveloped. Economic growth is based on the export of natural resources and remittance inflows, but the structure of the economy is monolithic. Main findings: Upon analysing transition indicators for the period 2000–2020, no evidence of significant changes towards a sustainable energy transition is found. All countries in the region (except Uzbekistan) have recorded an increase in carbon emissions, while the carbon intensity of the energy mix is almost the same. While there has been visible progress in reducing energy intensity, the countries in the region remain among the most energy-intensive economies. Despite the region's substantial potential for renewable energy production, it remains underutilized. Conclusions: A multitude of varied problems accompanies the green transition in Central Asian countries. The energy market that has not yet been liberalised, along with significant subsidies and low energy tariffs, discourages investments in renewable energy sources and energy efficiency initiatives. A high level of corruption, rigid legislative and institutional infrastructure, and insufficient capital are additional factors that determine the speed, scope, and effectiveness of the green transition. Thus far, the primary focus in these countries has been on ensuring energy security. However, there has been a discernible surge in investments (particularly from China) in renewable energy projects. Although energy efficiency and climate change issues are formally defined, the energy transition goals are often declarative without an action plan that provides concrete steps in transition process. Strategic planing of economic development that includes all related sectors (not only the energy sector) and paying attention to socio-economic and environmental indicators of sustainable development are prerequisites for successfully implementating the energy transition in these countries. [ABSTRACT FROM AUTHOR]

The role which corporate and financial secrecy vehicles play in enabling transnational corruption has justifiably received growing scholarly and policy interest. Less attention, however, has been given to the enabling role played by political secrecy vehicles. Political secrecy vehicles denote arrangements that allow individuals to clandestinely exercise public authority, which is concealed by a formal bureaucratic façade. This article develops analytical categories for deconstructing political secrecy structures and pinpointing the threat they pose to anti-corruption enforcement. These structures and threats are then empirically explored through an investigative case study. The case study plots how shadow political space in Uzbekistan and the simulacra of impartial public administration, was utilised by a kleptocratic syndicate to conceal an international bribery scheme, and then weaponised by the conspirators to successfully frustrate enforcement efforts in Europe. Drawing on key lessons from the case study, proposals are made for how the threats posed by political secrecy structures can be jurisprudentially and practically counteracted. [ABSTRACT FROM AUTHOR]

Soil temperatures at both surface and various depths are important in changing environments to understand the biological, chemical, and physical properties of soil. This is essential in reaching food sustainability. However, most of the developing regions across the globe face difficulty in establishing solid data measurements and records due to poor instrumentation and many other unavoidable reasons such as natural disasters like droughts, floods, and cyclones. Therefore, an accurate prediction model would fix these difficulties. Uzbekistan is one of the countries that is concerned about climate change due to its arid climate. Therefore, for the first time, this research presents an integrated model to predict soil temperature levels at the surface and 10 cm depth based on climatic factors in Nukus, Uzbekistan. Eight machine learning models were trained in order to understand the best-performing model based on widely used performance indicators. Long Short-Term Memory (LSTM) model performed in accurate predictions of soil temperature levels at 10 cm depth. More importantly, the models developed here can predict temperature levels at 10 cm depth with the measured climatic data and predicted surface soil temperature levels. The model can predict soil temperature at 10 cm depth without any ground soil temperature measurements. The developed model can be effectively used in planning applications in reaching sustainability in food production in arid areas like Nukus, Uzbekistan. [ABSTRACT FROM AUTHOR]

The optimal conditions for the isolation of valuable natural biopolymers were revealed. Chitosan (CH) was obtained from cysts of A. parthenogenetia in the Aral Sea and from pupae of the silkworm Bombyx mori. Chitosan was obtained from cysts of A. parthenogenetia with a molecular weight of 89 kDa, a degree of deacetylation (DDA) of 72% and a solubility of 81.62%. It has been shown that it is possible to isolate CH from silkworm pupae of sufficient purity with different molecular weights and DDAs depending on the synthesis conditions and the degree of purification. Bombyx mori CH has a higher molecular weight of 100–160 kDa, a high DDA, up to 90%, and a solubility of 88%. IR spectroscopy, X-ray diffraction and elemental analysis have shown the purity of the isolated CH from various sources. In chitin from A. parthenogenetia cysts of the Aral Sea, two types of modifications, α and β, with corresponding syngonies are observed, which confirms its polymorphic structure. The antibacterial activity of B. mori CH has been shown, which tends to expand the spectrum of suppressed bacteria with increasing concentration and have a bactericidal effect on both gram-negative and gram-positive bacteria. CH of B. mori had an immunostimulating effect on living organisms, which allows us to recommend drugs based on CH to strengthen the immune system. [ABSTRACT FROM AUTHOR]

As climate change becomes the greatest issue of this century, countries are looking for sustainable solutions to effectively control their greenhouse gas (GHG) emissions. Uzbekistan, being one of the most vulnerable countries to climate change effects, is taking notable actions toward a low-carbon economy. In this line, there is a significant need for a thorough assessment of the country’s current decarbonization measures, its prospects, and possible directions of CO2 emission reduction in both governmental and academic spheres, which is the primary aim of this research. To reach these objectives, this study estimates, for the first time, the carbon dioxide (CO2) emission trends in Uzbekistan and their sector-by-sector contribution. Additionally, various carbon emission reduction pathways are discussed emphasizing the potential for the transition to renewable energy sources (RES) and carbon capture, storage, and utilization (CCSU) technology integration. According to the results, the annual CO2 emission in Uzbekistan was about 116 Mt with 3.27 t per capita in 2021. Expectedly, with the share of 87%, power and industrial sectors contribute most to it. Over 80% of the country´s CO2 emissions come from natural gas combustion, producing low-concentration flue gas. The resulting increased cost of CO2 separation from large point sources decreases the CCSU application potential in the abundantly present oil and gas reservoirs. Under these circumstances, future investigations can focus on improving CO2 separation, exploring onshore and offshore storage, integrating RES, and promoting collaborative decarbonization actions among neighbouring countries.Highlights: The annual CO2 emissions and their sector-by-sector contribution in Uzbekistan are estimated and compared with other statistical databases In 2021, Uzbekistan's annual CO2 emissions were approximately 115.89 million metric tons, with a per capita rate of 3.274 metric tons. Power and industrial sectors contribute significantly, accounting for 87.7% of emissions. Modernizing and enhancing the existing power transmission infrastructure holds the potential to reduce greenhouse gas emissions by up to 2 million metric tons. Initial CO2 capture cost was calculated based on CO2 concentration in flue gases from various sources. Uzbekistan possesses a valuable opportunity to leverage CO2 for Enhanced Oil Recovery (EOR) and Enhanced Gas Recovery (EGR) due to its abundant natural gas and oil wells. [ABSTRACT FROM AUTHOR]

The possibility of obtaining a new alternative source of clay raw materials for making ceramic materials based on muddy deposits, possessing functional properties, from reservoirs is considered. The physicochemical properties of sediments from the muddy bottom of the Tuyamuyun reservoir in Uzbekistan were studied. It was found that the ceramic bodies developed based on the dual muddy-kaolin composition can be used to produce ceramic materials intended for construction. [ABSTRACT FROM AUTHOR]

The geodynamic features of the Fergana intermontane depression are the presence of rifting during regional meridional compression and the discrepancy between the location of earthquake sources and boundaries of inhomogeneities in crustal layers. The first feature is solved using the ideas of multistage plate tectonics, which also makes it possible to assess the oil and gas content of the basin. However, existing hypothetical tectonic schemes are not supported by mathematical calculations. To clarify these features, we have developed a mathematical model of the stress–strain state with respect to one of the cross sections of the crust in the Fergana depression, which has a zonally inhomogeneous density structure. The results of the mathematical model show that the presence of blocks with different densities creates displacements under the impact of horizontal compressive stresses. It is also shown that the isolines of maximum tangential stresses are located close to the boundaries of inhomogeneous zones, which indicates large errors in determining earthquake hypocenters. [ABSTRACT FROM AUTHOR]

Since the early 1960s, agricultural development in the irrigated areas of Uzbekistan resulted in a 90% decrease of the Aral Sea area, while the water salinity increased from 1 to 20%. The goal of the present work was to investigate the diversity of microbial communities of the water and sediments of the Western Aral Sea, as well as of the adjacent soils and basins, using high-throughput sequencing of the V4 variable region of the 16S rRNA genes. It was found that Aral Sea water with a salinity of 22% was inhabited by uncultured Archaea of the family Haloferacaceae (22‒43%), as well as by bacteria of the genera Spiribacter and Psychroflexus. In the Aral Sea sediments, the share of archaea was much lower (2‒17%), and among them uncultured Woesearchaeales predominated. Predominant bacteria of Aral sediments were sulfate reducers of the phylum Desulfobacterota, as well as members of the genera Fusibacter, Halanaerobium, Guyparkeria, Marinobacter, Idiomarina, and Thiomicrospira. In soil samples of the former Aral Sea bed with salinity of 8.2%, a variety of archaea of the phylum Halobacterota were present, as well as uncultured bacteria of the family Nitrosococcaceae. However, in the rhizosphere of Ewresmann's teresken plant (Kraschennininikovia ewresmanniana) growing there, archaea accounted for only 4% and mainly belonged to the family Nitrososphearaceae. In the rhizosphere microbiome, 33% of all prokaryotes were uncultured members of the phylum Actinomycetota. The microbial community of the teresken rhizosphere turned out to be similar to the soil microbial communities of the Ustyurt plateau located 3 km from the Aral Sea shore. The fresh water flowing along the former Aral Sea bed from an artificially drilled well also caused significant changes in the microbial communities: cyanobacterial mats and associated organotrophic bacteria developed along the stream bed with the increasing salinity (0.25‒2%). Finally, the greatest prokaryotic diversity was found in the microbial community of the Lake Sudochye sediment with salinity of 1%, which is probably a modern analog of the Aral Sea microbiome before its shallowing. [ABSTRACT FROM AUTHOR]

Tugai ecosystems of desert river valleys are one of the most affected and endangered landscape types. The largest areas of tugai vegetation in Uzbekistan are preserved in the lower reaches of the Amu Dar'ya River. The main massifs of poplar forests are there. To assess their current status, 284 relevés, representing tugai plant communities in the lower reaches of the Amu Dar'ya, have been analyzed. For each one, the position on ecological gradients was determined by species indicator values. It is shown that the scatter of relevés is the greatest for moisture gradient: from 17 to 97 grades, and it is noticeably smaller for pasture digression (2.5–6.5) and soil salinity (16.1–19.5). To reveal the relationships between the species composition and environmental factors, CCA ordination was performed. Groups of relevés, representing the native tugai vegetation and three ecological series connected with salinity, soil moisture, and anthropogenic pressure, are identified. According to them, four generalized plant communities, differing in species composition, floristic diversity, and structure, are distinguished. Indicator plants are identified on the basis of a formalized assessment of species constancy and importance values. The changes in species composition and structure of communities (life form spectra) are shown. It has been established that vegetation halophytization is the most active process following progressive desertification. This process is reflected in the replacement of poplar forests by shrub communities dominated by Halostachys belangeriana and Tamarix hispida. As a result of intensive anthropogenic impact, the vegetation is transformed and the importance value of ruderal annual plants becomes higher. [ABSTRACT FROM AUTHOR]

Production and processing of oil and gas are associated with the formation of a huge volume of wastewater of complex composition disposed in different ways after thorough treatment. Environmental control of the composition and degree of purification of oil- and gas-bearing wastewater requires using effective methods for determining various pollutants, including chloride and fluoride. The object of the study was a sample of wastewater from the largest gas field Mustakillikning 25 yilligi in the Surkhandarya region of the Republic of Uzbekistan. It was shown that the sample was salty (dry residue was 34.1–31.7 g/dm3) and had a neutral reaction. The method of atomic emission analysis of water revealed high concentrations of potassium, sodium, and sulfur, a significant amount of calcium and magnesium, and a significantly smaller amount of a number of other elements contained in water. Study of various methods of sample preparation for ionometric measurements of chloride ion shows that a significant proportion of chlorine is bound with organic components of water. It is shown that boiling (~100°C) or fusing at 800–850°C with NaOH eliminates the interfering effect of accompanying components (sulfur, iodine, and organic matter) on the chloride determination. The results obtained provide quantitative determination of the total content of chlorine in water both in the form of a free chloride ion and in a bound state, probably in the composition of organochlorine compounds. The presence of fluorine in the organic part of the sample has not been revealed. The possibility of using a single sample preparation (boiling or fusing) for the determination of both chloride and fluoride ions has been shown. The interfering effect of the accompanying elements upon fluorine determination is masked by a buffer solution regulating the total ionic strength. The developed procedures are easy to use, selective, and cost-effective. The trueness and precision of the developed techniques have been evaluated and proved using a method of varying the sample volume. [ABSTRACT FROM AUTHOR]

The total population of the Union republics is analyzed based on three tabulations of the 1926 population census, conducted in 1927–1928, 1937, and 1939. Through a comparative analysis of the results of the population censuses of 1937 and 1939, it is concluded that the redistribution of the total population among the republics did not seek to eliminate shortcomings in the conduct of the 1926 census since in all these tabulations the main indicator of the total population of the Soviet Union remained unchanged and amounted to 147 027 915 people. Most likely, the aim of this redistribution was to disguise the consequences of the demographic catastrophe associated with the famine of the early 1930s, especially in relation to Kazakhstan. In this context, this article also provides data on the population dynamics of the Central Asian republics from 1926 to 1939, obtained from three tabulations of the 1926 census. The results of these tabulations showed similar trends. It is concluded that the results of the first, earlier tabulations of the 1926 census materials are the least susceptible to distortion and can be used in scientific analysis. Another conclusion is that subsequent changes made to the 1926 census were intended to hide the consequences of the demographic catastrophe in the Soviet Union that had occurred as a result of the famine of the early 1930s. These changes were carried out by manipulating the redistribution of various categories of the population in the Union republics. In the Kyrgyz Autonomous Soviet Socialist Republic (Kyrgyz ASSR), the number of Kazakhs increased by 1749 people. [ABSTRACT FROM AUTHOR]

This study investigates soil radioactivity at the Pomuk gas field in Uzbekistan, a region with history of underground nuclear activity. Using a NaI (Tl) scintillation gamma spectrometer, soil samples were analyzed for concentrations of 232Th, 226Ra, 40K, and 137Cs. Concentrations were found to be in the range of 19.0–31.0 Bq/kg for 232Th, 12.0–32.0 Bq/kg for 226Ra, 450.0–634.0 Bq/kg for 40K, and 2.4–11.0 Bq/kg for 137Cs. Surface radon flux density was measured using a coal sorbent-based passive method, with values ranging from 26.1 to 79.0 mBq/m2s. Mean activity values for radium equivalent (Raeq) and gamma representative level index (Iγ) were calculated to be 75.2–96.5 Bq/kg and 0.3–0.4 Bq/kg, respectively. The absorbed airborne gamma dose rates (GDR) varied between 41.0 and 52.0 nGy/h, while annual effective dose rates (AEDR) were 0.3–0.4 μSv/year. The radiological risk assessment indicates the area is within safe limits for the population and environment, providing a foundation for future radiological monitoring programs. [ABSTRACT FROM AUTHOR]

This paper discusses the dynamics of ecosystems and their components in connection with the development of the Aral Sea environmental crisis. The theoretical basis of this study was the idea that the vegetation dynamics under the conditions of deltaic landscape desertification represents an anthropogenically-induced natural hologenetic process involving the replacement of vegetation typical for hydromorphic floodplain and reed-bed biotopes with vegetation of semihydromorphic meadow and solonchak biotopes resulting in the formation of zonal vegetation typical for automorphic biotopes. These endo–ecogenetic successions are determined by the directed reduction in moisture supply in biotopes and accompanying salinization and evolution of soils. The changes occur in both successional and catastrophic ways. In the northern, undeveloped part of the Amu Darya River delta, the reduction of the sea water surface and a sharp drop in water reserves resulted by the 1990s in the formation of environmental conditions typical for desert landscapes: the climate parameters and their regime became close to desert ones, while the groundwater level fell to a depth of 5–10 m, thus, making groundwaters inaccessible to plant roots. Reconstruction of the reservoir system and flooding of former marine bays contribute to the formation of hydromorphic conditions on local sites. Geobotanical studies commenced in the Amu Darya River delta in 1979 and involved route surveys and surveys of topo–ecological profiles passing through the main deltaic relief elements (levees, their slopes, and interchannel depressions) were repeated in the monitoring mode in 1985, 1993, and 1999. Route surveys performed in 2017 showed that the current vegetation dynamics stage involves the formation of desert plant communities. Black saxaul (Haloxylon aphyllum (Minkw.) Iljin) first discovered in the Muynak district in 1993 is actively spreading in the most part of the undeveloped delta that has turned into a wasteland after the extinction of common reed (Phragmites australis (Cav.) Trin. ex Steud.) communities in the 1970s–1980s. The desert species Krasheninnikovia ceratoides (L.) Gueldenst. that has invaded degrading tugai and sparse arborescent saltwort (Salsola dendroides Pall.) monocoenoses on takyr solonchak soils around the same years formed extensive thickets north of the city of Kungrad. Observations on topo–ecological profiles made it possible to examine individual changes and stages in more detail. On the right bank of the Akdar'ya River that feeds the Mezhdurechenskoe Reservoir, on the Porlytau topo–ecological profile located 3 km southwest of the upland of the same name, over the course of the 40-year observation period, the river washed away a section of the near-channel floodplain and levee 500 m wide and was incised 9 m into the ground following a drop in the erosion base level (i.e., water level in the eastern part of the Greater Sea) by 26 m. Plant communities successions develop slowly. They follow the path of successional replacement of an arboreal Рoplar tugai (Populus ariana + Populus pruinosa + Elaeagnus angustifolia–Mixteherbosa with a shrubby tugai with Tamarix ramosissima Ledeb. ending in a nearby section of the interchannel depression with a catastrophic change: the death of the Halostachys belangeriana (Moq.) Botsch. community. This community was formed in 1985 as a result of soil salinization in the area previously occupied by reeds. In 2017, a slow surface desalination process that began in 1993 due to the illuviation of salts from upper (0–10 cm) horizons to lower ones continued in the soil at all survey points on the profile. For the first time, the desert shrub species Krasheninnikovia ceratoides (L.) Gueldenst. was recorded on the tugai fringe in 2017; over time, this species will probably colonize this entire site characterized by the profile. In the northeastern part of the delta, on the Kunyadarya topo–ecological profile that begins on the right bank of the dry channel of the same name and descends in the southeastern direction to the coastal plain, a degrading Populus diversifolia-Halimodendron halodendron tugai on the levee is being replaced by a tamarisk tugai, which is indicated by the species composition of the community: Populus diversifolia-Tamarixlaxa + Halimodendron halodendron + T. ramosissima–Atriplex tatarica. In 2017, black saxaul was first recorded in a community formed by tall well-developed tamarisks and succulent saltworts located further along the profile on the levee slope. The profile enters a coastal solonchak plain with a Halostachys belangeriana–Climacoptera aralensis community. The salinity profiles of soils under all plant communities have a similar feature: the salt content reaches its maximum in the upper part of the profile (0–10 cm); then it sharply decreases in the 10–20-cm horizon and does not change down the profile to a depth of 50 cm. Salinity profiles of soils on two sites occupied by the tugai have the maximum similarity. The uppermost (0–5 cm) horizon is less saline or somewhat washed out from salts compared to the deeper (5–10 cm) horizon featuring the maximum salt content. In the Halostachys belangeriana community, the salt content reaches its maximum (8.28%) in the surface soil horizon (0–5 cm), then it sharply decreases to 2% in the 10–20-cm horizon, and further decreases down the profile to almost 1%. The salinity profile under tamarisk communities differs from other profiles: overall, it is slightly saline and has two maxima: mild surface salinity (0.5% at a depth of 0–5 cm) and medium salinity (0.8%) at a depth of 20–30 cm. Salinity profiles of soils on the Kunyadarya topo–ecological profile indicate progressive salinization of soils with a clearly pronounced surface-accumulative profile under the impact of pulsating secondary hydromorphism in this area provoked by water flows from the Dzhiltyrbas Bay towards the sea that occur on a periodic basis. In 2017, a newly-formed young woody tugai on the bank of an irrigation canal crossing the degrading Yerkin tugai was described. It differs from the degrading tugai forests described earlier in its full-fledged structure (it has three storeys) and in richness of its plant species composition (12 species). Two liana species are present, and renewal of predominant tree species occurs. The soil under the young tugai is alluvial–meadow–tugai (hydromorphic); it is slightly saline (0.36%) only in the near-surface horizon (0–5 cm). Comparison of data collected on topo–ecological profiles with data collected in the course of previous observations made it possible for the first time to conclude that the changes of plant associations in woody tugai communities in the undeveloped part of the delta under the desertification conditions occurs mainly in a successional way; while herbaceous and shrub communities, especially halophilic ones and their variants, are characterized by predominantly catastrophic changes. After their death, long-lasting wastelands are formed on lands previously occupied by such communities where favorable conditions for the introduction of species with different ecology are created. In local hydromorphic conditions with floodplain regimes, the formation and existence of tugai plant communities is possible. The practical significance of the results is that they characterize the diversity of environmental conditions and processes currently occurring in the vegetation and landscapes in the undeveloped part of the Amu Darya River delta and can be applied in resource use and biodiversity conservation practices. [ABSTRACT FROM AUTHOR]

The results of investigations of the chemical and mineralogical composition and main characteristics are presented to determine the suitability of trachybasalt porphyrite of the Karabulak section of the Gavasai deposit in Uzbekistan for preparing thermal insulation material, in particular mineral fiber. It was found that this new deposit of igneous rock can be used as the main raw material component in the manufacture of basalt fiber products, a widely demanded and modern material in the construction industry. [ABSTRACT FROM AUTHOR]

The results of investigations of the preparation of electrical porcelain based on available customary raw materials of Uzbekistan are presented. It is shown that in conditions of a shortage of high-grade mineral raw materials for the preparation of electrical porcelain it is advisable to introduce about half of the kaolin in a pre-calcined state into the mixture. In addition the products of firing primary and secondary Angrenskoe kaolins at 1350°C allow us to consider them as a mullite-containing component that subsequently imparts high physicomechanical and dielectric properties to the porcelain material. The phase composition of the resulting porcelain is represented mainly by new crystalline components — mullite and cristobalite, which allows it to be classified as an electric porcelain of the mullite-type. [ABSTRACT FROM AUTHOR]

The work is aimed at studying the effect of additions of oxides K2O, Na2O, MgO, Al2O3 on slag density and viscosity, as well as the separability and covering capacity of slag of the CaO–MnO–SiO2 system obtained by melting the fused flux during automatic arc welding of low-carbon steels. The subject of research is physicochemical and technological properties of slags, mechanical properties of welded joints obtained as a result of the process of automatic submerged arc welding. It is shown that with an increase in K2O and Na2O content slag density and viscosity, as well as the separability of the slag crust, decrease, and an increase in MgO and Al2O3 content increases slag density and viscosity. Based on results of the work, a composition of the slag base of fused flux is developed on the basis of oremineral raw materials of the Republic of Uzbekistan, selected on the basis of the CaO–MnO–SiO2 ternary system melting diagram. The results obtained make it possible to increase welded joint strength properties by 10–12%. [ABSTRACT FROM AUTHOR]

The new species Bibio takhtakarachensissp. n. is described from the mountains of Uzbekistan. It is characterized by a completely black body and darkened wings of the male. The new species is compared with the externally similar congeners from northern Iran and the Far East: B. alborzensis Krivosheina, B. arboricola Krivosheina, B. japonicus Motschulsky, and B. matsumurai Okada. [ABSTRACT FROM AUTHOR]

This study incorporated the index decomposition analysis to drive the GHGs emissions intensity and separate the impact into true efficiency and structural transformation of economic activities on GHGs emissions. The global perspective is investigated in three aspects; (i) global groups of countries regarding income level, (ii) global countries bifurcated into geo-political regions and, (iii) hundred countries are taken to perform individual country level analysis, by taking 20 years (2000–2019) data. The hundred countries are ranked regarding GHGs intensity, efficiency and economic activities with respect to (i) for the latest year performance, (ii) twenty years average performance and, (iii) annual average reduction of GHGs emissions, comparable with base year 2000. Income-based countries groups explicate the improvement of GHGs intensity for HIC only and the economic transformation contributed to it. Efficiency index for all income groups while economic activities of LMIC, MIC and UMIC deteriorated the GHGs emissions. Global geo-political regions explicate the mixed pattern of GHGs intensity. Efficiency index is best for Azerbaijan and least for Uzbekistan. While ranking average GHGs emission reduction countries; Zimbabwe is the best and Qatar is the last country in the intensity list. [ABSTRACT FROM AUTHOR]

Depositional settings of hemipelagic deposits of the Emsian (Dzhaus Beds, Zeravshan Range, Khodzha-Kurgan valley) are reconstructed, and the duration of eustatic events in this area is established on the basis of tentaculite and conodont zonation. In the studied region, the Emsian Khodzha-Kurgan transgression began at the end of the pireneae Zone and continued until the end of the patulus Zone. The transgression maximum occurs in the Dzhaus Beds. In the Dzhaus Beds, the presence of traces of two eustatic sea-level rises, accompanied by anoxic sedimentation, and one fall of the paleobasin level were revealed. The conclusions are derived from analysis of the lithology of the Dzhaus Beds and changes in the hydrodynamic regime in the sedimentary basin. Traces of the maximum subsidence of the sea level are recorded in interval 29–72 m of Member 16 (elegans tentaculite Zone, inversus conodont Zone). Sea level rise was recorded in the intervals of the entire Member 15, 0–28 and 73–102 m of Member 16 (elegans and cancellata tentaculite zones, inversus and serotinus conodont zones). In terms of time, the Dzhaus transgressions can be compared with the Czech Late Zlíchovian and Early Dalejan eustatic events. The change in the composition of the Dzhaus cephalopod, brachiopod, and ostracod associations occurs in the elegans tentaculite Zone. This gives the studied section a certain correlation value, since the details of the Emsian transgressions revealed in it can be used in the global correlation of eustatic events and be criteria for substantiate the position of the boundaries of the Emsian substages in the South Tien Shan. [ABSTRACT FROM AUTHOR]

Transboundary regional infrastructure development projects are prone to multiple and multilevel challenges and risks due to the involvement of the multiple heterogeneous and diverse nature of stakeholders. It is necessary to look deeply to avoid any discrepancy in timely and sustainable construction and development of the projects of transboundary nature which involve multiple and diverse stakeholders. The study serves this purpose. The study uses the Graph Model of Conflict Resolution method used to conclude the most suitable and agreed-upon Transboundary Transportation Project based on the preferences of the most relevant stakeholders. The findings of the conflict analysis provide valuable insights for governments and policymakers involved in developing and implementing transboundary transport corridors as part of the Central Asia Regional Economic Cooperation project. To strategize effectively in transboundary regional development initiatives, relevant stakeholders must be involved, and their preferences must be considered. This decision analysis adds to theory and practice by giving critical recommendations for the practical and long-term completion of such initiatives. [ABSTRACT FROM AUTHOR]

The LA–ICP–MS U–Pb age was determined for the first time for zircon from granodiorites–granites of the Sardara (Sarykty) intrusive in area of the giant Muruntau gold deposit in Western Tien Shan (Uzbekistan). Three crystal groups were identified in a combined sample: their concordant U–Pb age is 322.0 ± 3.7 (four grains), 301.6 ± 2.1 (11 grains), and 289.5 ± 4.9 Ma (two grains) (MSWD = 3.1, 0.17, and 0.98, respectively). The dispersion of the isotopic age can be explained using a model of a successive crystallization of different zircon generations in magmatic chambers at various depths and their further entrapment upon differentiation/crystallization of new magma portions. The similarity of two (youngest) age intervals with concordant U–Pb ages previously published for zircons of granitoid rocks directly at the Muruntau deposit is noteworthy. The latter ages could thus represent dike branching at the corresponding stages of evolution (progressive differentiation) of deeper sources of granitoid magma, the larger intrusions of which include Sardara (Sarykty) and other plutons exposed at some distance from the deposit. The older U–Pb isotopic ages of zircons from granitoids of the Sardara (Sarykty) pluton (~322 and 302 Ma) generally correspond to the subduction stage, whereas the youngest zircons (~289.5 Ma) correspond to the postcollision stage of the region. The origination and initial evolution of the magmatic sources in area of the Muruntau deposit could thus occur under subduction conditions; however, the final differentiation and crystallization of granitoid magma has finished at the postcollision stage. [ABSTRACT FROM AUTHOR]

Background: This article presents the results of a long-term study of the impact of rotavirus vaccination in Uzbekistan. Uzbekistan is the first country in the Central Asian region to introduce rotavirus vaccination into the national compulsory vaccination calendar. The study aimed to evaluate the impact of rotavirus vaccination on hospitalizations due to all-cause AGE and RVGE in children < 5 years of age in Uzbekistan. Methods: Detection of rotavirus antigen was performed using Rotavirus-Antigen-IFA-BEST "Vector Best" kit (Novosibirsk, Russia). Results: The total of 20,128 children under 5 years of age were hospitalized in sentinel hospitals with a diagnosis of acute gastroenteritis during the study period (2019–2020). Of this number of children, 4481 children (22.2%) were included in the study. Of 4481 children, 367 (8.2%) children tested positive for rotavirus. In our study, decrease in the rotavirus rate was noted in all age groups. The peak of rotavirus positivity occurred in the months of January and February. Conclusion: The average rotavirus-positive rate in the period (2019–2020) was 8.2% and the absolute percentage decrease was 18.1% compared to the pre-vaccination period (2005–2009) where the rotavirus-positive rate was 26.3%. The percentage of prevented cases averaged 68.8%. [ABSTRACT FROM AUTHOR]

The study of the ontogenetic structure of the coenotic populations of vulnerable, endemic, and rare plant species makes it possible to assess their state under the conditions of anthropogenic transformation of ecosystems and develop the scientific basis for their protection. Central Asia is one of the centers of origin and species diversity of the genus Tulipa L. In the flora of the Republic of Uzbekistan, there are 34 species of tulips, of which 19 species (55.88%) are endangered due to the collection of flowers and bulbs and overgrazing and habitat destruction. These are listed in the national Red Book. This article is devoted to the assessment of the current state of 13 coenotic populations of five rare and endemic species of the genus Tulipa (T. borszczowii, T. butkovii, T. dubia, T. greigii, T. korolkowii), growing in the Tashkent region of Uzbekistan in areas with different environmental regimes and levels of anthropogenic pressure. It has been established that eight studied cenopopulations are normal and full-membered; five populations are incomplete, they lack senile individuals, which is a biological feature of the genus Tulipa. Six cenopopulations belong to the left-sided type, their ontogenetic spectrum coincides with the characteristic spectrum of the genus Tulipa; four coenopopulations have a centered type of spectrum, while three are bimodal. The low proportion of juveniles in some of the cenopopulations studied is due to the influence of overgrazing, as well as high competition with other species in the community. It is recommended that a rare endemic of the Central Asian deserts be included in the next edition of the Red Book of Uzbekistan Tulipa borszczowii and national endemic, narrow-local endemic of the Chatkal ridge Tulipa butkovii. It is recommended to create a protected area (zakaznik or natural monument) to preserve the relic sandy massif Dalverzinskie sands in the Tashkent region. [ABSTRACT FROM AUTHOR]

NbS have gained substantial attention in the academic literature recently as a potential approach for simultaneously tackling environmental issues and addressing societal challenges. Drylands, which are among the world's most vulnerable areas to the impacts of climate change and cover a little less than the half of the global terrestrial surface, were the focus of this study. We conducted a systematic literature review to explore the potential opportunities for the application of NbS in rural drylands across the globe. We go on to specifically consider the possibility of applying selected NbS approaches in the Aral Sea region of Uzbekistan, as a case study of a dryland ecosystem illustrating major environmental and social challenges. We highlight which NbS show the most promise in the Aral Sea region and conclude with a discussion of existing gaps in the literature on NbS in drylands, and opportunities for further research. [ABSTRACT FROM AUTHOR]

Oulema duftschmidi (Redtenbacher, 1874), Phyllotreta astrachanica Lopatin, 1977, and Ph. procera (Redtenbacher, 1849) are recorded for the first time for Uzbekistan; Longitarsus stragulatus dichrous Khnzorian, 1962 is recorded for the first time for Tajikistan. The geographic distribution of Acolastus pallidus (Lopatin, 1956) and Aphilenia ornata Reitter, 1889 is clarified. For all the taxa considered, images of the adult habitus and male genitalia (for some of them) are given. [ABSTRACT FROM AUTHOR]

Soil salinity is a fundamental barrier to soil fertility, particularly in dry climates, and is a limiting factor for agricultural output and subterranean water utilization. Soil salinity significantly restricts agricultural soils in Uzbekistan. Remote sensing and satellite images were used to evaluate soil salinity in the Mingbulak District of Uzbekistan. In October 2019, soil samples were taken from various locations and analyzed, and soil salinity indices were calculated. The region's soil salinity was then mapped and modeled. The results revealed that SI 12 and the NDSI from Landsat 8 were superior to the others. The accuracy of the single band B2 and that of salinity indices SI1 and SI8 of Landsat 8 and Sentinel-2A were higher in the deeper layers than in the upper. NDSI was used to model the relationship between soil salinity (electrical conductivity) and the prominent salt ion The model was validated successfully, and a soil salinity map was created. According to the findings, the NDSI provided more accurate information on soil salinity than the other salinity indices, and the blue band was successful in depicting sublayers and the overall salinity of the region. [ABSTRACT FROM AUTHOR]

The "passive" sorption detectors based on the activated charcoal together with scintillation spectrometry were utilized to measure radon flux density from the soil surface as well as volumetric activity of indoor radon at the dwellings of rural areas of Uzbekistan. Additionally, gamma dose rates as well as concentrations of natural radionuclides in soil and building materials samples were determined. Based on the values of natural radionuclides, common radiological indices have been calculated. It was found that varying greatly, 94% radon flux density values did not exceed 80 mBq/(m2·s), while volumetric activities of radon were in the range of 35–564 Bq/m3. The radium equivalent activity for studied soil and building materials samples were below the allowed limit of 370 Bq/kg. Computed gamma dose rates were in the range of 55.50–73.89 ƞGyh−1 below the limit of 80 ƞGyh−1 and annual effective dose rate 0.068–0.091 mSvy−1, the average value of which was higher than the standard limit > 0.47 mSvy−1. The gamma representative index range was 0.89–1.19 with an average of 1.002 which was higher than the standard limit of 1.0. The range of activity utilization index was equal to 0.70–0.86 with an average value 0.77 which was lower than the recommended level ≤ 2.0. And lastly, excess lifetime cancer risk index values were from 1.9 × 10−4 to 2.5 × 10−4 and were lower than the recommended value 2.9 × 10−4 indicating low radiological risk. The results are consistent with the research conducted by other authors earlier, implying suitability of employing the method for the assessment of residential areas. [ABSTRACT FROM AUTHOR]

This article provides an analysis of the lipids and polysaccharides found in Arundo donax, a plant commonly used in Eastern folk medicine. The study focused on the leaves and roots of the plant, determining their fatty acid compositions and the composition of polysaccharides. The results showed that the leaves contained 2.65% lipids, while the roots contained 1.29% lipids. The polysaccharides in both the aerial parts and roots were primarily composed of pectins and hemicelluloses, with varying ratios of monosaccharide residues and degrees of esterification. The study concluded that the polysaccharides in A. donax were heteropolysaccharides and low-esterified pectins. [Extracted from the article]

The current work presents the results of neutron activation analysis applied to determine the elemental composition of ancient metallurgical slags found by archaeologists in the medieval settlement "Eski Khovos" in Uzbekistan. In Uzbekistan, archaeological artifacts, including products of archaeometallurgy, are predominantly studied using traditional descriptive techniques. Two slag-like object samples and three fragments of clay furnace walls were irradiated by thermal neutrons at the research reactor of the Institute of Nuclear Physics of Uzbekistan. The comparative analysis method enabled the identification of up to 34 different chemical elements in these samples (As, Au, Ba, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Ga, Hf, K, La, Lu, Mn, Mo, Na, Nd, Rb, Re, Sb, Sc, Sm, Sn, Sr, Ta, Tb, Th, U, W, Yb, Zn). The findings of this study suggest that the fragments are remnants of blacksmithing slags. The established methods of neutron activation analysis and processing of characteristic gamma spectra of activated samples hold significant interest for archaeologists of Uzbekistan, as they provide valuable new insights into the provenance, production techniques, and technological advancements of the archaeological artifacts, which in turn contribute to a better understanding of the region's historical and cultural development. [ABSTRACT FROM AUTHOR]

The results of investigations of the chemico-mineralogical and fractional compositions as well as physicochemical properties of glauconite sandstones of the Changi deposit are presented. Enrichment methods were selected and thermal activation was conducted. The coloring properties, hiding power, and oil absorption of the obtained brown and green pigments were investigated. It was been determined that this glauconite sandstone can be used as a raw material for the production of coloring pigments in the building materials industry and the manufacture of ceramic glazes at manufacturing enterprises in Uzbekistan. [ABSTRACT FROM AUTHOR]

Introduction: Uzbekistan is one of the countries with the highest number of diet-related chronic diseases, which is believed to be associated with high animal fat intake. Sheep meat is high in fats (~ 5% in muscle), including saturated and monounsaturated fatty acids, and it contains nearly twice the higher amounts of n-3 polyunsaturated fatty acids and conjugated linoleic acids compared to beef. Nevertheless, sheep meat is considered health promoting by the locals in Uzbekistan and it accounts for around 1/3 of red meat intake in the country. Objectives: The aim of this study was to apply a metabolomics approach to investigate if sheep meat intake frequency (SMIF) is associated with alterations in fasting blood plasma metabolites and lipoproteins in healthy Uzbek adults. Methods: The study included 263 subjects, 149 females and 114 males. For each subject a food intake questionnaire, including SMIF, was recorded and fasting blood plasma samples were collected for metabolomics. Blood plasma metabolites and lipoprotein concentrations were determined using 1H NMR spectroscopy. Results and Conclusion: The results showed that SMIF was confounded by nationality, sex, body mass index (BMI), age, intake frequency of total meat and fish in ascending order (p < 0.01). Multivariate and univariate data analyses showed differences in the levels of plasma metabolites and lipoproteins with respect to SMIF. The effect of SMIF after statistical adjustment by nationality, sex, BMI, age, intake frequency of total meat and fish decreased but remained significant. Pyruvic acid, phenylalanine, ornithine, and acetic acid remained significantly lower in the high SMIF group, whereas choline, asparagine, and dimethylglycine showed an increasing trend. Levels of cholesterol, apolipoprotein A1, as well as low- and high-density lipoprotein subfractions all displayed a decreasing trend with increased SMIF although the difference were not significant after FDR correction. [ABSTRACT FROM AUTHOR]

This paper examines for the first time the relationship between CO2 emissions and the consumption of renewable and non-renewable energy in Uzbekistan, spanning the period 1985–2020. The analysis uses the Autoregressive Distributed Lags (ARDL) model to estimate the long-run dynamic multipliers and short-run elasticity coefficients of energy consumption variables. Economic factors, such as GDP, are excluded in the analysis as they may cause multicollinearity problems. The empirical results document that in the short- and long-run, hydropower (renewable) energy consumption negatively impacts CO2 emissions per capita, showing a unidirectional causal effect. As regards with non-renewable energy consumption, natural gas and oil energy consumption have a positive impact on CO2 emissions per capita both in the short and long run. Coal consumption positively impacts CO2 emissions in the short run, while it is negative in the long run. Policy measures to enhance the collection of energy from additional renewable energy sources, in particular hydropower, should be taken into account in order to increase the share of renewable energy, and thus, to compensate non-renewable energy consumption which is the main contributor to CO2 emissions. Moreover, solar and wind energy should be explicitly taken into consideration as an additional renewable energy source, which has the lack of attention by policymakers. Furthermore, policy actions, such as the involvement of the private sector into renewable energy projects and the implementation of effective carbon tax policies, could be further options to reduce CO2 emissions. [ABSTRACT FROM AUTHOR]

We present the results of a comparative analysis of the available atmospheric absorption data for millimeter waves on the Suffa plateau (southern Uzbekistan). It is shown that the atmospheric absorption values at wavelengths of 3 and 2 mm published in G. Bubnov, et al., EPJ Web of Conferences 195, 09002 (2018) are much smaller than the data obtained for the Suffa site according to other sources. The optical depth we calculated on the basis of the global model of the atmosphere from the NASA website also shows that the data of the above work are underestimated by a factor of two. As a result, the actual astroclimate conditions of the Suffa plateau are, in particular, much worse than the Terskol peak in Russia and Koluch-Kul site in Tajikistan. Also, in the same work, we have found an overestimation of atmospheric absorption values by about 1.5 times at a wavelength of 2 mm for another site (Karadag landfill) compared with the values we obtained during independent processing of the same data. Therefore, the data given in the above article for the Suffa plateau cannot be considered reliable, and they should not be used when choosing sites for millimeter-wave antennas. [ABSTRACT FROM AUTHOR]

The giant gold deposit Muruntau in most works belongs to the "orogenic type". However, in the description of the geology of the deposit, there is usually no information about the stages (deformation, metamorphism) and the role of regional processes in the formation of host and mineralized rocks of the deposit. Our fieldwork provides unique geological evidence and previously unpublished data that are not reported in any other publications to date. This article presents the results of a detailed structural study of the terrane hosting the Muruntau gold deposit on the example of four sites and the results of deep drilling of two wells. The conducted studies confirm that the lowest Muruntau megaterrane consists of multi-stage metamorphosed Neoproterozoic–Early Paleozoic sedimentary-volcanic rocks and Late Paleozoic carbonate sediments overlain by Late Carboniferous flysch and olistostrome in the top. Two main stages (D1 and D2) of rock deformation in the lower part of the megaterrane associated with the Early Paleozoic accretion and two subsequent stages (D3 and D4) associated with the Late Paleozoic accretion and orogeny are described. Thrust processes D2 and D3 caused the formation of recumbent folds of different orientation and vergence. The normal antiform (D4) extending W–E is an orogenic fold. The Muruntau gold deposit is located in a regional synmetamorphic thrust zone called the Main Muruntau Thrust (MMT), which formed during the Early Paleozoic D2 stage. The MMT is responsible for the formation of secondary rock anisotropy along the cleavage of the D2 recumbent folds and conformal lens-like body of mineralized rocks and gently sloping veins with an area of 7.0 × 2.6 km. The internal structure of the deposit retains fragments of deformed gold quartz veins into recumbent folds. These structural data make it possible to link low-grade gold mineralized zones with Early Paleozoic deformations. We suggest that rock anisotropy within the MMT controlled mineralization twice: in the Early Paleozoic as a synmetamorphic flat high-permeable zone and in the Late Paleozoic as a relatively low-permeable zone for post-magmatic fluids. [ABSTRACT FROM AUTHOR]

The new natural saponin 3β,16α-dihydroxy-23-oxo-oleanan-28,13β-olide (1) was isolated from the aerial part of Saponaria officinalis. Its structure was established by analyzing 1D and 2D NMR spectroscopic and high-resolution mass-spectrometric data. The antimicrobial activity of the new saponin against the microorganisms Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Bacillus subtilis, and Candida albicans was studied. [ABSTRACT FROM AUTHOR]

The results of γ-spectroscopic research of the concentrations and vertical distributions of natural 226Ra, 232Th, 40K, technogenic 137Cs, and cosmogenic 7Be radionuclides in soils, the radon flux density in the surface air, and the radon concentration in waters in some regions of the Nurata, Karatepa, Chakilkalyan, and Gissar mountains of Uzbekistan are presented. The dependence of these values on the physiographic characteristics of areas, the intensity of natural and anthropogenic processes occurring on them, weather, and other factors was revealed. [ABSTRACT FROM AUTHOR]

Hydropower plays a very important role in the socioeconomic development of Kyrgyzstan. The Naryn River is formed in the high mountains of the inner Tien Shan, flows through the territory of Kyrgyzstan and Uzbekistan, and has one of the most extensive basins in Central Asia, with significant hydropower potential. A cascade of hydro power plants (HPPs) has been built on the river, which supply the country's electricity needs and provide annual and long-term regulation of water use in the region. New HPPs, including the Kambarata-1 HPP, the largest HPP of the cascade, with a rated capacity of 1860 MW, are currently being designed to increase power generation. The future reservoir of this HPP requires a comprehensive study and determination of all parameters for a detailed assessment of the environmental impact, as well as for ensuring reliability and economic efficiency of its construction and operation. The bed of the future reservoir is located in a remote mountainous area; therefore, in this work, computer modeling and calculation of its volume and surface area are performed on the basis of freely available global digital surface models (DSMs) and digital terrain models (DTMs) using geoinformation technologies. A comparative analysis of the capabilities of freely available global AW3D30 DSM, ASTER GDEM V003 DTM, GLO-30, SRTM Plus, and NASADEM with a 30-m spatial resolution for application in hydrological modeling is conducted. Based on the selected AW3D30 DSM, the volumes and surface areas of the reservoir at different water levels are determined. The obtained results indicate the possibility of using modern DSMs and DTMs based on space data in the design and operation of reservoirs in the mountain conditions of Kyrgyzstan. [ABSTRACT FROM AUTHOR]

The results obtained in additional archaeological and archeoseismological research within the limits of the settlement of Balandtepa and the Kirkhujra fortress once again prove that the ancient city of Eilatan perished in the 1st century BC. The city of Pap (Bab) was built no later than the end of the 6th–beginning of the 5th century BC on the site of the settlement of Kyrkhujra, which is located 2 km south of the modern city of Pap, on the right bank of the Syr Darya River. During this time, it was destroyed several times by floods and remained under mudflow deposits. After each flood, the city was almost completely rebuilt. The city on Kirkhujra was destroyed at the end of the 4th–beginning of the 5th century AD due to a very strong earthquake. After this seismic event, people left the territory of the destroyed city and built a new city on the Balandtepa monument located 1 km west of Kirkhujr. Additional information obtained about the unusual arrangement of detrital horizons in the talus (the tail of the destruction of the northern fortress wall of Balandtep) indicates that the wall was destroyed not by one, but by three strong earthquakes, which apparently occurred at the end of the 6th–beginning of the 7th centuries AD. During each subsequent earthquake, fragments of bricks flew off to ever greater distances with a decreasing height of the wall. It turns out that each subsequent seismic event was stronger than the previous one. Earthquakes of this sequence can only have a swarm or doublet nature, which is typical for a given territory. The Pap swarm of 1984, which occurred in this zone, and the Gazli earthquakes of 1976 and 1984 in the zone of the South Tien Shan seismogenic zone evidence this. At the same time, an analysis of archaeological materials shows that, at the beginning or the first quarter of the 8th century, there was some kind of natural cataclysm, as a result of which the owner of the citadel and the inhabitants of the shahristan (inner city) moved to the rabad (outer city). Their places were taken over by artisans, who worked there until the last quarter of the 8th century. [ABSTRACT FROM AUTHOR]

At the beginning of the 20th century, two subspecies of the eastern mole vole, Ellobius tancrei, were described from the lowland parts of Uzbekistan: E. t. fusciceps from Samarkand and E. t. ognevi from Bukhara. However, neither subspecies has since been recognized. At the same time, according to our studies, these two subspecies show significant differences in the morphometrics of the skull, the characters based on which both were described. Along with the study of the skull, using our original method, our studies are supplemented by an analysis of the morphometric parameters of the humerus. Based on a comprehensive analysis, we believe that the previously described subspecies of the eastern mole vole from the lowlands of Uzbekistan deserve to be recognized. [ABSTRACT FROM AUTHOR]

The main vectors of the US foreign policy strategy regarding the countries of Central Asia (CA) after the collapse of the Soviet Union are analyzed. It is noted that there are three main vectors in the US strategy in Central Asia: geopolitical, economic, and political−ideological, and humanitarian, which in many cases are closely intertwined with each other. Kazakhstan and Uzbekistan are of the main interest to the United States there. The authors draw attention to the fact that the US strategy in this region has an obvious anti-Russian and anti-Chinese orientation, which has intensified during the crisis of 2021‒2022, caused by the refusal of the United States and its allies to meet the legitimate claims of the Russian Federation adequately to ensure its security. [ABSTRACT FROM AUTHOR]

The results of studies of chemical, x-ray phase, microscopic, electron microscopic, and granulometric analyses as well as the technological properties of quartz sand from the Tamdin deposit are reported. It was established that this quartz sand can be used in industrial enterprises of Uzbekistan as a promising source of high-quality raw materials for the production of glass and glass-ceramic materials for technical, household, and construction purposes. [ABSTRACT FROM AUTHOR]

Mantle intrusive rocks (lamproites and basalts) were collected from different units of the Uzbek Tian Shan, Central Asia to investigate xenoliths and xenocrysts aiming at tracking the shallow or deep nature of the mantle source. Whole-rock geochemistry and petrography revealed that these rocks are mostly of basaltic composition and may contain various exotic materials. These rocks originate from composite mantle magmas; they often result from the mixing between an evolved primary melt and more primitive melts, as indicated by the composition and textures of clinopyroxenes. Olivine, orthopyroxene and spinel mineral geochemistry from xenocrysts and lherzolitic xenoliths is consistent with a shallow mantle source (spinel lherzolite). Trace element content of clinopyroxenes shows LREE depletion supporting the removal of the magma from an undepleted sub-continental lithospheric mantle. The latter one is heterogenous, though and some parts recorded evidence of intense metasomatism. The upwelling asthenospheric magmas, emplacing in trans-lithospheric structures, were probably directly transferred into the crust or just below the crust, without significantly changing the geochemical composition of the sub-continental lithospheric mantle. [ABSTRACT FROM AUTHOR]

Anomalies in the ionic and gas composition of groundwater before earthquakes (hydrogeochemical precursors, hereinafter HGCP) are considered according to data of systematic observations in ten self-flowing wells and springs in seismically active regions of Russia (Kamchatka Peninsula), Uzbekistan, Japan, and Iceland. Using an extended set of earthquake parameters, it was shown that HGCP were manifested for 1–9 months in the near and intermediate zones of the future earthquake sources with Mw = 5.3–7.8. Such properties of hydrogeochemical precursors allow their use for predicting the magnitude and time of expected seismic events, as well as their impact in the observation area. A model is presented for a registered precursor in the form of the ionic composition of groundwater in self-flowing well based on observational data on concentrations of anions and cations and on a mathematical model for the mixing of two waters of contrastingly different composition in a zone of increased conductivity. Calculations for one of the wells are presented as an illustrative example of the chemical composition of two mixing waters in the aquifer and in the wellbore. This model and observational data are used to estimate parameters of the disturbed state of the well–aquifer system during the preparation of an earthquake: the relaxation time of the water pressure pulses (t0) and the movement time of mixed water (τ0). The morphology and duration of HGCP are controlled by relations between t0 and τ0. The further development of HGCP studies and their application in predicting earthquakes require a technical modernization of the system of hydrogeochemical observations and the development of HGCP models for individual wells. [ABSTRACT FROM AUTHOR]