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Ecological water replenishment is an important measure for conserving water sources and improving the water environment. To explore the evolution and causes of groundwater chemistry after ecological water replenishment in the Jialu River, this study utilized groundwater monitoring data from 2015 to 2019 following ecological water replenishment. Various methods, including Piper’s trilinear diagram, Gibbs diagram, principal component analysis, and ion ratio analysis, were employed for research purposes. The results indicate that (1) since the implementation of ecological water replenishment in the Jialu River, there has been a general downwards trend in total dissolved solids (TDS) in groundwater. The dominant cation in groundwater is Ca 2+ , whereas HCO 3 − is the dominant anion. The concentration of cations in groundwater has generally decreased, with noticeable reductions in SO 4 2− and Cl − concentrations in the upper reaches of the recharge river contributing to improved groundwater quality. (2) A comparison with 2015 reveals a gradual transition at sampling points from chemical types such as HCO 3 -Ca·Mg and HCO 3 ·Cl–Ca·Mg to an ecological water replenishment chemical type (HCO 3 -Ca).

As a result of fluctuations in the shallow groundwater table, hydrodynamic conditions change alongside environmental conditions and hydrogeochemical processes to affect pollutant migration. The study aimed to investigate the migration, adsorption, and desorption characteristics of Pb on fine, medium, and coarse sand in the water table fluctuation zone by using several laboratory methods, including the kinetic aspects of Pb2+ adsorption/desorption and water table fluctuation experiments. The results showed that the adsorption and desorption curves fit the Elovich equation well at a correlation coefficient above 0.9. In the adsorption and desorption kinetic experiments for fine, medium, and coarse sand collected and from the floodplain, the maximum adsorption capacity of Pb2+ was 2367 mg·kg−1, 1848 mg·kg−1, and 1544 mg·kg−1, respectively. The maximum desorption capacity of Pb2+ was 29.18 mg·kg−1, 62.38 mg·kg−1, and 81.60 mg·kg−1, respectively. In environments with pH greater than 4, the adsorption capacity was proportional to the pH, but the desorption capacity decreased as the pH increased in water. As the water table varied, the lowest pH occurred in the polluted medium we set initially. When the distance between the pollutants and sample solution grew further, pH increased, and the Pb2+ concentration decreased in the sample solution. In the column experiment of water table fluctuations on coarse sand, Pb2+ migrated nearly 5 cm upward from the original pollutant and migrated less than 10 cm downward from that. In our experiments on medium and fine sand, the upward and downward migration distances were <5 cm. The groundwater table fluctuations, pH variation, and Pb concentration currently influence the migration of Pb.

Groundwater level fluctuation alters hydrodynamic conditions and hydrogeochemical action, thus affecting the migration and transformation of pollutants. This study investigated the effect of groundwater level fluctuations on Pb migration processes. We selected two typical media, coarse sand and medium sand, for the soil column experiments and numerical simulations of the Pb migration process in the groundwater level fluctuation zone. The soil column experiments showed that when the contaminants were distributed at a 30–40 cm depth in the soil column, the Pb migrated into the water in the range of 20–45 cm in coarse sand, while the range of Pb migration in medium sand decreased to 30 cm–40 cm. We constructed a numerical model of Pb migration in the aeration zone–saturation zone coupled with water transport and solute transport by HYDRUS-1D. The model simulated the migration process of Pb in different amplitude and frequency of water level fluctuation and initial concentration of pollutants. The results showed that the coarse sand column and medium sand column showed relatively noticeable changes in Pb concentration in water at 30–40 cm and 30–35 cm, respectively. The migration range and concentration of Pb in water are proportional to the medium particle size and the frequency of water level fluctuation, and inversely proportional to the magnitude of water level fluctuation. The Pb concentration in the water increased or decreased as the initial pollutant concentration of the medium increased or decreased. Its variation is basically the same as the variation of the initial contaminant concentration. The research results can provide a scientific basis for the remediation of heavy metal pollution in groundwater.

The Middle Route Project of South-to-North Water Diversion (MRP) has effectively increased the amount of available water resources in the receiving areas of the Beijing-Tianjin-Hebei region, curbed the trend of declining groundwater levels, expanded the area of landing funnels, and increased the magnitude of ground subsidence, and enabled the groundwater system to play an important ecosystem service value. This article classified groundwater ecosystem services in the receiving areas of Beijing-Tianjin-Hebei into four categories: provisioning services, regulating services, supporting services and culture services, according to the classification of the Millennium Ecosystem Assessment. We constructed an ecosystem service value assessment index system and a monetized quantitative value assessment model to assess the groundwater ecosystem services value (GESV) around the commissioning of the MRP, and analyzed the contribution of the MRP to the GESV. The results showed that the total annual average of the GESV in the receiving areas of Beijing-Tianjin-Hebei before the water connection was 124.298 billion yuan, and after the water connection was 144.033 billion yuan, of which the value of the regulating and supporting services increased and the value of the supply services decreased. The enhancement of the GESV in the water-receiving areas of Beijing-Tianjin-Hebei by the MRP has increased year by year, and its contribution to the GESV increased from 10.508 billion yuan in 2015 to 49.354 billion yuan in 2019.

Traditional finishing technology is difficult to realize the precision machining of complex geometric parts. Abrasive flow machining technology solves this problem well. Taking the spur internal gear as the research object, the wall shear force, static pressure, dynamic pressure, and abrasive velocity vector of the internal channel of the straight internal gear under different inlet velocity, abrasive concentration, and abrasive particle size are analyzed by using the large eddy simulation method, and the action law of different parameters on the machining of straight internal gear by solid–liquid two-phase abrasive flow is discussed. At the same time, the orthogonal test was carried out. The results show that the solid–liquid two-phase abrasive flow machining technology can effectively remove the burrs, pits, and bulges on the tooth surface of spur internal gear, reduce the tooth surface roughness, and improve the surface quality. The optimal combination of processing parameters and the primary and secondary order of various factors affecting processing are obtained by range analysis and analysis of variance. The regression equation is constructed by regression analysis to verify the effectiveness and accuracy of the model, which provides theoretical support and data reference for actual processing and production. Graphic abstract

Rapid object recognition has survival significance. The extraction of topological properties (TP) is proposed as the starting point of object perception. Behavioral evidence shows that TP processing takes precedence over other geometric properties and can accelerate object recognition. However, the mechanism of the fast TP processing remains unclear. The magnocellular (M) pathway is well known as a fast route to convey “coarse” information, compared with the slow parvocellular (P) pathway. Here, we hypothesize that the fast processing of TP occurs in a subcortical M pathway. We applied single‐pulse transcranial magnetic stimulation (TMS) over the primary visual cortex to temporarily disrupt cortical processing. Besides, stimuli were designed to preferentially engage M or P pathways (M‐ or P‐biased conditions). We found that, when TMS disrupted cortical function at the early stages of stimulus processing, non‐TP shape discrimination was strongly impaired in both M‐ and P‐biased conditions, whereas TP discrimination was not affected in the M‐biased condition, suggesting that early M processing of TP is independent of the visual cortex, but probably occurs in a subcortical M pathway. Using an unconscious priming paradigm, we further found that early M processing of TP can accelerate object recognition by speeding up the processing of other properties, e.g., orientation. Our findings suggest that the human visual system achieves efficient object recognition by rapidly processing TP in the subcortical M pathway. The present study provides TMS evidence that a subcortical M pathway is responsible for the early processing of TP and this subcortical processing of TP accelerates object recognition. The current findings shed light on a new function of the subcortical pathway, that is, involved in the early processing of shape perception of objects.

Background Previous research has highlighted the ability of Homeobox A10 (HOXA10) to the promote proliferation, migration, and epithelial-mesenchymal transformation of various cancers, including lung adenocarcinoma (LAD), which is characterized by an aggressive disease course that exhibits rapid proliferation and migration, with studies suggesting histone deacetylase 1 (HDAC1) to be a downstream mediator of HOXA10. The current study aimed to investigate the mechanism by which HOXA10-mediated HDAC1 influences the development of LAD. Methods The expression patterns of HOXA10, HDAC1, DNA methyltransferase 1 (DNMT1), and Kruppel-like factor 4 (KLF4) were determined. Additionally, the effect of HOXA10, HDAC1, or DNMT1 on invasive phenotypes of LAD was analyzed using depletion experiments. The interactions among HOXA10, HDAC1, DNMT1, and KLF4 were evaluated via chromatin immunoprecipitation, dual luciferase assay or co-immunoprecipitation. Furthermore, the tumorigenic ability of the LAD cells following HOXA10 silencing and/or HDAC1 overexpression in vivo was also investigated. Results In the LAD tissues and cells, HOXA10, HDAC1, and DNMT1 all exhibited high levels of expression, while KLF4 was poorly expressed. HOXA10 silencing inhibited the expression of HDAC1, reduced LAD cell proliferation, migration, and invasion, and promoted the apoptosis. HDAC1 promoted DNMT1 expression through deacetylation, and DNMT1 inhibited the KLF4 expression through DNA methyltransferase. The in vitro findings were further attested through the use of in vivo assays. Conclusion Taken together, the key observations of the current study highlight the role of HOXA10 and HDAC1 in promoting the proliferation and migration of LAD cells. HOXA10-induced upregulation of HDAC1 interacts with DNMT1-KLF4 axis, while the inhibition of HOXA10 or HDAC1 represents a promising anti-tumor therapy target for LAD.

Gears play an important role in modern machinery and are indispensable transmission components, particularly at high speeds, where lubrication is essential for the reliability and efficiency of the gear unit. In order to study the oil coverage law and heat dissipation mechanism of high-speed rotating meshing gears by injection angle, this paper adopts the moving particle semi-implicit method to establish a high-speed rotating gear lubrication model, study the intrinsic effect of different jet angles on gear lubrication, and build a gear lubrication bench for experimental verification. Numerical simulation found that with an increase in spray angle, the gear surface coverage and heat transfer coefficient of the high-speed rotating transmission gears initially increase and then decrease. They reflect the same lubrication law characteristics. When the injection angle was 90°, the surface coverage and heat transfer coefficient values were at their greatest, resulting in the best spray lubricating effect. According to the experimental results, under the conditions of 0.5 MPa injection pressure and high-speed rotation of the transmission gear with vertical injection, the lubricant covers the largest surface area of the gear and the least power loss. Simultaneously, in our previous study, we experimentally obtained the optimal parameter conditions on the basis of which we derived. The effect of nozzle diameter on jet lubrication was investigated in a previous study, and in this article, the effect of nozzle angle and distance on gear lubrication is investigated; the optimal conditions for high-speed lubrication of gears are the incident distance of 3.5 cm, incident angle of 90°, incident diameter of 1.5 mm, and gear speed of 2000 r/min, and the lubrication effect reaches the best ideal state; reduction in oil loss due to oil injection lubrication and power loss due to different parameters of the lubrication system. Lubrication design provides a theoretical foundation for the transmission system.

Background White clover ( Trifolium repens L.) is an excellent leguminous cool-season forage with a high protein content and strong nitrogen-fixing ability. Despite these advantages, its growth and development are markedly sensitive to environmental factors. Indole-3-acetic acid (IAA) is the major growth hormone in plants, regulating plant growth, development, and response to adversity. Nevertheless, the specific regulatory functions of Aux/IAA genes in response to abiotic stresses in white clover remain largely unexplored. Results In this study, we identified 47 Aux/IAA genes in the white clover genome, which were categorized into five groups based on phylogenetic analysis. The TrIAAs promoter region co-existed with different cis-regulatory elements involved in developmental and hormonal regulation, and stress responses, which may be closely related to their diverse regulatory roles. Collinearity analysis showed that the amplification of the TrIAA gene family was mainly carried out by segmental duplication. White clover Aux/IAA genes showed different expression patterns in different tissues and under different stress treatments. In addition, we performed a yeast two-hybrid analysis to investigate the interaction between white clover Aux/IAA and ARF proteins. Heterologous expression indicated that TrIAA18 could enhance stress tolerance in both yeast and transgenic Arabidopsis thaliana . Conclusion These findings provide new scientific insights into the molecular mechanisms of growth hormone signaling in white clover and its functional characteristics in response to environmental stress.

Astilbe chinensis , a perennial ornamental plant in the Saxifragaceae family, is recognized for its medicinal properties due to its diverse secondary metabolites. Here, we generate a chromosome-level genome assembly of A. chinensis . Our analysis provides compelling evidence that A. chinensis experienced a whole-genome triplication event, which preceded the diversification of the Saxifragaceae family. Furthermore, we identify a biosynthetic gene cluster that includes nine terpene synthase (TPS) genes. Among these, the gene AcTPS2 encodes a eudesma-5,7-diene synthase, and the product is confirmed using nuclear magnetic resonance spectroscopy. A synteny analysis of this gene cluster across various representative plant species reveals variations in the number, sequence, and function of TPS genes, indicating that neo-functionalization of these TPS genes likely occurred after speciation. Collectively, the genome sequence of A. chinensis lays the foundation for genetic and evolutionary studies of the Saxifragaceae family and provides insights into terpene synthases discovery. Astilbe chinensis is a perennial ornamental and medicinal plant in the Saxifragaceae family. Here, the authors report chromosome level genome assembly of this species and reveal the origin and evolution of a terpene biosynthetic gene cluster.