In recent years, copper pollution has gradually become one of the major problems of soil environmental pollution. Lignin plays an important role in plant resistance to biotic and abiotic stresses. CCoAOMT is a key enzyme in the lignin biosynthesis process. In this study, the CCoAOMT gene family members of Platycodon grandiflorus were identified by bioinformatics methods, and their basic characteristics and potential functions were analyzed. The results showed that five members of the PgCCoAOMT gene family were identified in P. grandiflorus, with protein lengths ranging from 246 to 635 amino acids, and were evenly distributed on four chromosomes. Phylogenetic analysis indicated that the PgCCoAOMT gene family was divided into two subclades, namely Clade1a, Clade1b, Clade1c, Clade1d, and Clade2. The cis-regulatory element analysis of the promoter revealed that the PgCCoAOMT members contained a large number of cis-regulatory elements responsive to stress, and conjecture PgCCoAOMT2, PgCCoAOMT4, and PgCCoAOMT5 were involved in the lignin synthesis. The qRT-PCR results showed that, within 5 days of copper stress treatment, except for the PgCCoAOMT4 gene, the other genes exhibited different expression levels. Furthermore, the expression levels of all five PgCCoAOMT genes increased significantly at 7 days of treatment. With the increase in the number of days of treatment, the content of lignin in the seedings of P. grandiflorus showed a trend of increasing first and then decreasing under copper stress. In general, in the copper stress treatment of 1-3 days, the transcriptional inhibition of PgCCoAOMT1 and PgCCoAOMT3 and the increase in lignin content contradicted each other, suggesting that there was post-translational activation or alternative metabolic pathways compensation. Meanwhile, in the 7-day treatment, the coordinated up-regulation of the genes was accompanied by the failure of lignin synthesis, which pointed to the core bottleneck of metabolic precursors depletion and enzyme activity inactivation caused by root damage. Research objective: This study reveals the expression level of the PgCCoAOMT gene in the seedings of P. grandiflorus under copper stress, providing a theoretical basis for elucidating the mechanism of P. grandiflorus response to copper stress and for subsequent improvement of root resistance in P. grandiflorus.

Approximately 3.44 billion tons of copper mine tailings (MT) were produced globally in 2018 with an increase of 45% from 2010. Significant efforts are being made to manage these tailings through storage facilities, recycling, and reuse in different industries. Currently, a large portion of tailings are managed through the tailing storage facilities (TSF) where these tailings undergo hydro-thermal-mechanical stresses with seasonal cycles which are not comprehensively understood. This study presents an investigative study to evaluate the performance of control and cement-stabilized copper MT under the influence of seasonal cycles, freeze-thaw (F-T) and wet-dry (W-D) conditions, representing the seasonal variability in the cold and arid regions. The control and cement-stabilized MT samples were subjected to a maximum of 12 F-T and 12 W-D cycles and corresponding micro-and-macro behavior was investigated through scanning electron microscope (SEM), volumetric strain (epsilon v), wet density (r), moisture content loss, and unconfined compressive strength (UCS) tests. The results indicated the vulnerability of Copper MT to 67% and 75% strength loss reaching residual states with 12 F-T and 8 W-D cycles, respectively. Whereas the stabilized MT retained 39%-55% and 16%-34% strength with F-T and W-D cycles, demonstrating increased durability. This research highlights the impact of seasonal cycles and corresponding strength-deformation characteristics of control and stabilized Copper MT in cold and arid regions. (c) 2025 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/

The tomato is among the crops with the most extensive cultivated area and greatest consumption in our nation; nonetheless, secondary salinization of facility soil significantly hinders the sustainable growth of facility agriculture. Melatonin (MT), as an innovative plant growth regulator, is essential in stress responses. This research used a hydroponic setup to replicate saline stress conditions. Different endogenous levels of melatonin (MT) were established by foliar spraying of 100 mu molL-1 MT, the MT synthesis inhibitor p-CPA (100 mu molL-1), and a combination of p-CPA and MT, to investigate the mechanism by which MT mitigates the effects of salt stress on the photosynthetic efficiency of tomato seedlings. Results indicated that after six days of salt stress, the endogenous MT content in tomato seedlings drastically decreased, with declines in the net photosynthetic rate and photosystem performance indices (PItotal and PIabs). The OJIP fluorescence curve exhibited distortion, characterized by anomalous K-band and L-band manifestations. Exogenous MT dramatically enhanced the gene (TrpDC, T5H, SNAcT, and AcSNMT) expression of critical enzymes in MT synthesis, therefore boosting the level of endogenous MT. The application of MT enhanced the photosynthetic parameters. MT treatment decreased the fluorescence intensities of the J-phase and I-phase in the OJIP curve under salt stress, attenuated the irregularities in the K-band and L-band performance, and concurrently enhanced quantum yield and energy partitioning ratios. It specifically elevated phi Po, phi Eo, and psi o, while decreasing phi Do. The therapy enhanced parameters of both the membrane model (ABS/RC, DIo/RC, ETo/RC, and TRo/RC) and leaf model (ABS/CSm, TRo/CSm, ETo/CSm, and DIo/CSm). Conversely, the injection of exogenous p-CPA exacerbated salt stress-related damage to the photosystem of tomato seedlings and diminished the beneficial effects of MT. The findings suggest that exogenous MT mitigates salt stress-induced photoinhibition by (1) modulating endogenous MT concentrations, (2) augmenting PSII reaction center functionality, (3) safeguarding the oxygen-evolving complex (OEC), (4) reinstating PSI redox potential, (5) facilitating photosynthetic electron transport, and (6) optimizing energy absorption and dissipation. As a result, MT markedly enhanced photochemical performance and facilitated development and salt stress resilience in tomato seedlings.

We present a multidisciplinary research aimed at quantifying the conditional probabilities for hazards associated with pyroclastic avalanches at Etna, which combines physical and numerical modeling of granular avalanches and probabilistic analysis. Pyroclastic avalanches are modeled using the depth-averaged model IMEX-SfloW2D, which is able to simulate the transient propagation and emplacement of granular flows generated by the collapse of a prescribed volume of granular material. Preliminary sensitivity analysis allowed us to identify the main controlling parameters of the dynamics, i.e. the total avalanche mass, the initial position of the collapsing granular mass (and the associated terrain morphology), the initial avalanche velocity, and the two rheological parameters which determine the mechanical properties of the flow. While the first two parameters can be considered as scenario parameters in the definition of the hazards, the initial velocity and the rheological parameters need to be calibrated. We therefore adopted a methodology for the statistical calibration of the physical model parameters based on field observations. We used data from the pyroclastic avalanche that occurred on February 10, 2022 at Etna, for which we had an accurate mapping of the deposit and some estimates of the total mass and the initial volume. We then run a preliminary ensemble of numerical simulations, with fixed initial volume and position, to calibrate the other input parameters. Based on the accuracy of the matching of the simulated and observed deposits (measured by the Jaccard Index), we extracted from the simulation ensemble a subsample of equally probable combinations of initial velocities and rheological parameters. We then built an ensemble of model input parameters, with varying (i) avalanche volumes, (ii) initial positions, (iii) velocity, and (iv) rheological coefficients. The initial volume range was chosen within the range of observed pyroclastic avalanches at Etna (i.e., between 0.1 and 3 x 106 m3), using a prescribed probability distribution extracted from the literature data. The initial positions have been chosen on the flanks of the South East Crater of Etna, with homogeneous spatial distribution. The initial velocity and the rheological coefficients were chosen from the subsample created with the calibration. Finally, a semi-automatic procedure (digital workflow) running the Monte Carlo simulation allowed us to produce the first probabilistic map of pyroclastic avalanche invasion at Etna. Such a map, conditional to the occurrence of a pyroclastic avalanche event, can be used to identify the hazardous areas of the volcano and to plan mitigation measures.

Innovative powder coating system for hydraulic steel construction Unprotected steel corrodes in the atmosphere, water and soil. In order to ensure structural safety and maintain fatigue strength, steel structures of all kinds must be protected from corrosion. Hydraulic steel structures such as locks, gates, canal bridges, ship lifts and water power plants largely characterize our waterways, coastal fortifications and port facilities. They are exposed to a particularly high level of corrosive attack because, in addition to atmospheric influences such as wind and weather, they are particularly affected by water, constant water changes and aggressive substances such as salts and minerals. Since such constructions and buildings usually represent investments of the century, their preservation, use and operational safety over generations is an economic necessity. But it ' s not just corrosion that poses a problem for hydraulic steel construction; the formation of biofilms and the growth of algae and mussels can also lead to problems that can even lead to a restriction in the functionality of the systems. The newly developed powder coating system prevents both and thus helps to extend maintenance intervals, increase the lifecycle of steel components in hydraulic steel construction and reduces the lifecycle costs. The new powder coating system thus makes an innovative and sustainable contribution to the preservation of structures in hydraulic steel construction.

Micron-scale crack propagation in red-bed soft rocks under hydraulic action is a common cause of engineering disasters due to damage to the hard rock-soft rock-water interface. Previous studies have not provided a theoretical analysis of the length, inclination angle, and propagation angle of micron-scale cracks, nor have they established appropriate criteria to describe the crack propagation process. The propagation mechanism of micron-scale cracks in red-bed soft rocks under hydraulic action is not yet fully understood, which makes it challenging to prevent engineering disasters in these types of rocks. To address this issue, we have used the existing generalized maximum tangential stress (GMTS) and generalized maximum energy release rate (GMERR) criteria as the basis and introduced parameters related to micron-scale crack propagation and water action. The GMTS and GMERR criteria for micron-scale crack propagation in red-bed soft rocks under hydraulic action (abbreviated as the Wmic-GMTS and Wmic-GMERR criteria, respectively) were established to evaluate micron-scale crack propagation in red-bed soft rocks under hydraulic action. The influence of the parameters was also described. The process of micron-scale crack propagation under hydraulic action was monitored using uniaxial compression tests (UCTs) based on digital image correlation (DIC) technology. The study analyzed the length, propagation and inclination angles, and mechanical parameters of micron-scale crack propagation to confirm the reliability of the established criteria. The findings suggest that the Wmic-GMTS and Wmic-GMERR criteria are effective in describing the micron-scale crack propagation in red-bed soft rocks under hydraulic action. This study discusses the mechanism of micron-scale crack propagation and its effect on engineering disasters under hydraulic action. It covers topics such as the internal-external weakening of nano-scale particles, lateral propagation of micron-scale cracks, weakening of the mechanical properties of millimeter-scale soft rocks, and resulting interface damage at the engineering scale. The study provides a theoretical basis for the mechanism of disasters in red-bed soft-rock engineering under hydraulic action. (c) 2024 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting by Elsevier B.V.

Currently, in agriculture, there is a tendency towards the partial replacement of chemical pesticides with microbiological plant protection products. In this work, we tested the ability of plant-growth promoting bacteria from the genus Azospirillum to reduce the negative effects of high concentrations of six different pesticides on wheat characteristics. Of the seven Azospirillum strains studied, five showed high resistance to at least one pesticide, and Niveispirillum irakense (formerly classified as Azospirillum until 2014) was one of the most resistant strains to all pesticides. In most cases, catalase activity increased in resistant strains in the presence of pesticides. Furthermore, we demonstrated that some of the most resistant Azospirillum strains (including N. irakense, A. brasilense, A. picis, A. thiophilum, and A. baldaniorum) can counteract pesticide-induced growth inhibition, suppress oxidative stress, as evidenced by a decrease in iron-induced chemiluminescence and the amount of oxidative damage to wheat seedling mtDNA in a pot experiment. However, the bacteria had no positive effect on the chlorophyll content of wheat seedlings. Azospirilla were found in the rhizosphere of wheat roots 3 months after a wheat planting in the field experiment. Pesticides led to a slight decrease in their quantity in the rhizosphere. Additionally, bacterial inoculation mitigated the pesticide-induced decrease in wheat biomass.

In order to meet long-term air transportation needs, Hong Kong International Airport (HKIA) has been constructing the third runway system (3RS) through land reclamation projects since 2016. However, the third runway and taxiway, which were paved in September 2021, suffered from severe surface settlement. Therefore, we attempted to reveal the settlement pattern within the 3RS and analyze the factors contributing to this displacement. Employing the multi-temporal interferometric synthetic aperture radar (MT-InSAR) technique, we utilized PAZ, COSMO-SkyMed, and Sentinel-1 satellite images to extract ground displacements along the radar line of sight. The results show that, compared with COSMO-SkyMed and Sentinel-1 images, PAZ demonstrates superior performance in the deformation monitoring of the HKIA, with more deformation details and larger displacements. The maximum settlement rate derived by PAZ on the 3RS exceeds 110 mm/year. To ensure the reliability of the derived displacements along the LOS, we validated them through cross-validation, comparing the outcomes from different SAR data with data from GPS stations. In order to gain a detailed deformation information, we derived the vertical and horizontal (ground range direction) displacements by utilizing deformation measurements along the LOS of multiple SAR satellites and the geometric information, and the maximum values recorded for vertical and E-W displacements reached 88.31 mm/y and 41.91 mm/y, respectively. Furthermore, our investigation revealed that the significant local deformation observed on the taxiway and third runway was predominantly attributed to various factors including the creep of soft soil, consolidation of filling materials, characteristics of road surface materials, and distinct stages of construction.

Soils contaminated with per- and poly- fluoroalkyl substances (PFAS) require immediate remediation to protect the surrounding environment and human health. A novel animated clay -polymer composite was developed by applying polyethyleneimine (PEI) solution onto a montmorillonite clay-chitosan polymer composite. The resulting product, PEI -modified montmorillonite chitosan beads (MMTCBs) were characterized as an adsorptive soil amendment for immobilizing PFAS contaminants. The MMTCBs exhibited good efficiency to adsorb the PFAS, showing adsorption capacities of 12.2, 16.7, 18.5, and 20.8 mg g -1 for PFBA, PFBS, PFOA, and PFOS, respectively, which were higher than those obtained by granular activated carbon (GAC) (i.e., an adsorbent used as a reference). Column leaching tests demonstrated that amending soil with 10% MMTCBs resulted in a substantial decrease in the leaching of PFOA, PFOS, PFBA, and PFBS by 90%, 100%, 64%, and 68%, respectively. These reductions were comparable to the values obtained for GAC-modified soil, particularly for long -chain PFAS. Incorporating MMTCBs into the soil not only preserved the structural integrity of the soil matrix but also enhanced its shear strength (kPa). Conversely, adding GAC to the soil resulted in a reduction of the soil ' s mechanical properties.

The paper demonstrates how the concepts presented in the companion paper: Determination of Constrained Modulus of Granular Soil from In Situ Tests-Part 1 Analyses can be applied in practice. A settlement design based on the tangent modulus method is described. Extensive in situ tests were performed on a well-documented test site consisting of sand with silt and clay layers. The field tests comprised different types of penetration tests, such as the cone penetration test, the flat dilatometer, and the seismic down-hole test. The modulus number and the constrained tangent modulus were derived from the cone penetration test with pore water pressure measurement and the flat dilatometer test. In addition, the shear wave speed was determined from two seismic down-hole tests, from which the small-strain shear modulus could be evaluated. The constrained modulus obtained from the cone penetration test with pore water pressure measurement (CPTU) and the flat dilatometer (DMT) was compared with that from the seismic down-hole tests. The importance of the stress history on the constrained modulus was demonstrated. The range of modulus numbers, derived from different in situ tests, compares favorably with empirical values reported in the literature.