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Ho Chi Minh City, Vietnam’s largest city, located on the lower reaches of the Sai Gon-Dong Nai (SG-DN) river system, is facing increasingly severe flooding due to changes in river flow and water levels. This article presents the results of a study to assess the impact of hydraulic structures located in the upper reaches on the water level in the lower reaches of the SG-DN River. As part of a study to assess the impact of upstream reservoirs and flood control structures on the water level in the lower reaches of the SG-DN River, hydrological data of the river network were collected and a hydraulic model was developed based on a digital elevation model (DEM) using the software package Mike 11, Mike 21 and Mike Flood. The water level of the Sai Gon River from the upper reaches to the Thu Dau Mot measuring station directly depends on the Dau Tieng reservoir, and the Tri An reservoir directly affects the water level in the river section from behind the Tri An dam to the Dong Nai section in the Tam An - Long Phuoc area. In the sections of the Sai Gon and Dong Nai rivers, which are less affected by the two overlying reservoirs, it is necessary to develop preventive measures to supply sufficient fresh water to meet the needs of the population and industries. In areas prone to flooding and underflooding as a result of the operation of anti-flood locks, it is also necessary to reconstruct hydraulic structures (raise the elevations of foundations, expand drainage systems, build reservoirs for collecting flood water etc.)

The largest economic center in Vietnam - Ho Chi Minh City, is facing increasingly serious riverbank erosion, one of the main reasons being the flow. Therefore, in this study, the flow velocity field on the Saigon River section is accurately analyzed in different time intervals with the help of MIKE 11 and MIKE 21 models. The simulation results show that The number of flow velocities in the middle of the river is 3-4 times greater than that of the two banks. However, between high tide and low tide, the flow on both sides of the river is faster than the main flow, especially in the upper part of the winding banks, such as the section from Ben Nghe sluice to Tan Thuan, sewer and river section from An Loi Dong Ward police station to Thu Thiem Bridge 2. The velocity value on the studied river section, in most cases, exceeds the allowable value of the non-erosion velocity of the bed material particles. , riverbanks, as well as suspended sediment particles. Therefore, the erosion process on both sides of the river will occur regularly and continuously, so urgent measures are needed to protect the riverbank. During the operation of the anti-flood sluice, the flow velocity will decrease slightly before sluices also appear as whirlpools. The flow velocity on the Saigon River has a complex distribution and changes from time to time depending on the flood discharge from Dau Tieng Lake and the tidal currents of the East Sea.

Ho Chi Minh City, Vietnam's largest city, located on the lower reaches of the Sai Gon-Dong Nai (SG-DN) river system, is facing increasingly severe flooding due to changes in river flow and water levels. This article presents the results of a study to assess the impact of hydraulic structures located in the upper reaches on the water level in the lower reaches of the SG-DN River. As part of a study to assess the impact of upstream reservoirs and flood control structures on the water level in the lower reaches of the SG-DN River, hydrological data of the river network were collected. A hydraulic model was developed based on a digital elevation model (DEM) using the software package Mike 11, Mike 21 and Mike Flood. The water level of the Sai Gon River from the upper reaches to the Thu Dau Mot measuring station depends on the Dau Tieng reservoir, and the Tri An reservoir directly affects the water level in the river section from behind the Tri An dam to the Dong Nai section in the Tam An - Long Phuoc area. In the sections of the Sai Gon and Dong Nai rivers, which are less affected by the two overlying reservoirs, it is necessary to develop preventive measures to supply sufficient fresh water to meet the population's and industries' needs. In areas prone to flooding and underflooding due to the operation of anti-flood locks, it is also necessary to reconstruct hydraulic structures (raise the elevations of foundations, expand drainage systems, build reservoirs for collecting flood water, etc.)

Using an information model of a capital construction object greatly simplifies the interaction within the construction and technical expertise framework, eliminates redundant procedures, and reduces the duration, labor intensity, and cost of construction and technical expertise (judicial, pre-trial, corporate). In this regard, the article provides a complex of measures for the development of informatization of construction and technical expertise, which can be represented as a combination of three components: theoretical, methodological, and practical. Using the capital construction object's information model significantly simplifies the interaction within the construction and technical expertise framework, eliminates redundant procedures, and reduces the duration, labor intensity, and cost of construction and technical expertise (judicial, pre-trial, corporate). In this regard, the article presents a set of measures for the development of informatization of construction and technical expertise, which can be represented as a combination of three components: theoretical, methodological, and practical. From the point of view of practical value, the proposed set of measures indicates the main directions for the digitalization of construction and technical expertise, which can be projected onto other aspects of investment and construction activities.

The adoption of appropriate tactical decisions is central to the organization of operational and production controlling in the construction industry. The article discusses the issues of using simulation modelling when optimizing the schedule for performing a complex of construction and installation works performed in the process of operational and production control.

The paper analyzes the dynamics of planned and deep deformations on the section of the Amudarya River in the area of the damless water intake in the main structure of the Karshi Main Canal-KMC. The results of field studies of the state of the canal situation of the Amudarya River at the site of a damless water intake are studied. The course of riverbed processes in the riverbed is studied. Recommendations for improving water intake conditions have been developed. According to the results of the field survey and the study of the head section of the supply canal, the state of the Amudarya riverbed in the water intake zone was assessed. The results of surveys of the hydraulic and pumping modes of sediments of the Amudarya River in the area of the damless water intake are analyzed and summarized. The results of field studies of the canal situation of the Amudarya River in the water intake area in the Amudarya River KMC in the area of the Karshi head water intake are studied. The riverbed situation is not characterized by constant hydraulic characteristics over time for the same water flow rate, i.e. with the same water horizon marks, the flow rates may differ from each other by about half, and with the same flow rates, the horizon marks may vary up to ± 0.6 m. This is explained by the extreme instability and high mobility of the canal, and large deformations of the canal occur in a short time. The hydraulic regime of the river is characterized by a significant redistribution of speeds, depth and width of the flow. The range of their changes is within: Maximum speed >Vmax =2…5 m/s; average speed Vav = 0.5…2.5 m/s; depth H max = 4…14 m, Hav = 1…5 m; width B = 300…2000 m; slope i = 0.00016…0.0003. It is established that the characteristic feature of the river is that at a constant flow can have different average velocities depth and width, for example, when Qw = 1000 m3/s, respectively, v = 0.6…1.7m/s, B = 180…1030m, Hav = 1.1…4.3m.

The article presents the results of the analysis of the deep deformations of the Amu Darya riverbed in the upper reaches of the low-pressure reservoir. The analysis of the combined transverse profiles of the riverbed in different sections of the upper reaches of the Takhiatash reservoir showed that the coastal zones are most intensively silted up. At the same time, the core zone with the highest flow rates is very weakly declared. The height of the silting layer along the length of the upper stream increases in the direction of the dam. The silting area extends upstream for a length 2-3 times longer than the length of the soundings section, which is 17.5 km. To ensure the normal operation of the hydraulic system, it is recommended that conditions should be created for a normal and stable approach of the flow to the hydraulic system, which should be ensured by maneuvering the shield holes. To do this, it is necessary to create conditions for the erosion of the left-bank spillway by increasing the water flow through the extreme left-bank discharge holes. Flushing of the upper left-bank section of the river should continue until the optimal width of the leading channel is reached, which provides the main flow of the stream in front of the structure. It is proved that the formation and development of sediment deposits on the right bank between sections 8-10 leads to a change in the flow correction and creates conditions for the formation of shoals in front of the regulator of the Kizketken channel, which can complicate the operation of the water intake zone. Therefore, it is necessary to take measures to prevent the development of the right-bank channel, and the development of the channel should go from the main channel. As shown by monitoring operating mode Takhiatash waterworks, in the Takhiatash district waterworks intensive processes the channel formation, which has a strong influence on the operational mode of the dam, especially in the operation of the water intakes flushing of sediments, skip flood costs through the shields of the dam and the stability of structures.

The article discusses optimal versions for placement of ventilation systems for deep-laid underground lines, performed in a closed way, with the removal of the ventilation chamber from the ventilation output and placing it either in the ventilation shaft or in a specially constructed ventilation chamber located near the trunk, which significantly simplifies the design of excavation, and as a result, speed up its construction. To reduce the construction time, it is proposed to perform parallel work on the vent development and the ventilation chamber, including the possible installation of process equipment in parallel with the mining operations during the construction of the metro by the underground method.

As noted by a number of experts in the field of the quality of construction of capital construction objects, at present there are no industry-specific methods for assessing the quality of construction and installation works in construction. The quality assessment and acceptance of capital construction objects is carried out according to the criterion of compliance with the requirements established in the project documentation, the working documentation prepared on its basis and the requirements established in the regulatory documents. It should be noted that the more complex the object, the larger the construction volume, the longer the construction period of the object and the harder it is to achieve full compliance of the object with the established requirements due to the lack of a methodology for choosing organizational decisions, as well as changing regulatory requirements, technological variability, errors.The current situation necessitated the development of an assessment model and the adoption of organizational decisions to ensure the quality of construction. This article highlights and discusses the main factors affecting the quality of organizational decisions. A system for assessing the level of quality assurance of construction is proposed, taking into account the quality of organizational decisions and the main factors cited.

The deposition rate is sufficiently studied in the case of single particles or in conditions of low concentrations of suspended matter, in which the precipitating particles do not affect each other. In the article, the method of calculation of the rate of the constrained deposition is offered, comparative calculations of the rate of the free and constrained deposition of particles are executed, the settlement results reflecting essential difference of the speed of the constrained and free deposition of particles are presented. The factors influencing the rate of confined deposition, among which the main one is the concentration of suspended matter in water, are considered. The experimental data confirming the reduction of speed of the constrained deposition of more than 3 times in a five-fold increase in the concentration of suspended solids is given. The dependence of the strained deposition rate of particles on the concentration of the suspension is obtained.

Solving the problems of quality assurance is an integral element of the development strategy of any industry, including the investment and construction sector. Ensuring product quality is not only a competitive advantage, but also helps to reduce unforeseen resources and time costs from the occurrence of nonconformities, which has a positive effect on the economic condition of the manufacturer. The article discusses areas of modernization of quality assurance systems for the construction of nuclear power facilities.

The role of metal ions in the mechanism of light-stimulated redox activity of potential anticancer agent 2-phenyl-4-(butylamino)naphtha[2,3-h]quinoline-7,12-dione (Qc) has been studied by CIDNP (chemically induced dynamic nuclear polarization) and EPR methods. The photo-induced oxidation of NADH and its synthetic analog - substituted dihydropyridine (DHP) - by quinone Qc was used as a model. The Qc capability of producing chelating complexes with divalent metal ions of Fe, Zn and Ca was studied quantitatively by optical absorption spectroscopy. A significant decrease of electrochemical reduction potential of Qc (Δ E=0.4−0.6 eV for ACN and ACN/PBS solutions) in chelating complexes and in protonated form of Qc was observed. A pronounced increase in efficiency of DHP oxidation in chelating complexes with Zn2+ and Ca2+ ions compared with free Qc was demonstrated. The yields of free radicals, including reactive oxygen species (ROS) and reaction products, were a few times higher than those in the absence of metal ions. Application of such chelating compounds to enhance ROS generation looks very promising for anti-cancer therapy, including the photodynamic therapy. [ABSTRACT FROM AUTHOR]

Bovine syndactyly is an autosomal monogenic recessive trait associated with multiple mutations in the LRP4 gene encoding low-density lipoprotein receptorrelated protein 4. This protein is a specific facilitator of sclerostin-mediated inhibition of both Wnt1/β-catenin signaling and osteocyte-secreted bone formation. It is assumed that sclerostin induces a decrease in extracellular pH and promotes the release of calcium ions from mineralized substrates. Therefore, mutations in the LRP4 gene might be associated with changes in the elemental status. The aim of this research was to evaluate the elemental composition of serum in cattle carrying multiple SNP in the LRP4 gene (16 trial animals) compared to animals without such mutations (62 control animals). DNA samples from 78 Black Pied cattle were sequenced with a TruSeq Bovine Parentage Sequencing Panel (Illumina, USA) on a MiSeq Illumina platform following by SNP analysis. The elemental composition of the serum was determined using ICP-AES and ICP-MS. The levels of Ca and P, crucial bone elements, were higher in trial cattle than in control group by 12.9% (P = 0.004) and 22.5% (P = 0.008), respectively. The level of V affecting the uniform distribution of calcium salts in bones, was higher in trial group than in control one by 34.5% (P = 0.001). The concentrations of Mn and Mg were higher in trial group than in control one by 23.6% (P = 0.026) and 10.0% (P = 0.044), respectively. The Sr level in trial cattle was higher by 18.8% (P = 0.04) that may indicate the rickets-like state. A similar trend was observed for toxic metals As and Li. This study demonstrates the association of the LRP4 multiple SNP and the changes in cattle elemental status. Moreover, such heterozygous animals have a higher risk of mineral metabolism disorders. This research was supported by The Ministry of Science and Higher Education of the Russian Federation (Project No. 0526-2019-0001). [ABSTRACT FROM AUTHOR]