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To solve the problems of rotor position estimation error caused by the installation deviation of Hall sensors and the increase in yarn amount detection error in complex environments, resulting in speed fluctuations and unstable yarn feeding in the traditional permanent magnet synchronous motor (PMSM) drive system for yarn feeder, a control method for yarn amount in yarn feeder PMSMs based on an improved dual second-order generalized integrator (DSOGI) and Kalman filter is proposed. Firstly, in order to reduce the influence of installation deviation of Hall sensors, the three-phase Hall signals are converted into two-phase orthogonal Hall vector signals. An improved DSOGI is used to filter out high-order harmonic components and specific harmonic components in the Hall vector signals, and a cross-coupled structure is constructed to further enhance the fundamental component and suppress high-order harmonic components of negative coefficients. Then, accurate motor rotor position information is extracted by a quadrature phase-locked loop; secondly, in order to obtain accurate information on yarn amount, a system state model based on yarn amount and its rate of change is established, and Kalman filtering is used for optimal estimation of the yarn amount; finally, the above methods are integrated into the PMSM control system of the yarn feeder. Experimental results show that, compared with traditional methods, the PMSM control system of the yarn feeder using the method proposed in this paper has a shorter startup time and smaller steady-state error in motor speed and yarn amount when conveying yarn at a constant speed; when transporting yarn at variable speed, the motor speed and yarn amount settling time are shorter, and the peak deviation is smaller.

This paper extends the data-driven computational mechanics paradigm to nonlinear materials characterized by the Duncan–Chang Elastic-Bulk (E-B) constitutive model. Unlike in linear elastic systems, geotechnical media exhibit stress-dependent tangent moduli and non-convex constitutive manifolds. We propose a recursive nested data-driven solver that dynamically adapts the phase-space distance metric to account for pressure-dependent hardening. A rigorous mathematical analysis of convergence is provided, demonstrating that the solver’s performance is governed by the local transversality between the conservation law constraint set and the nonlinear material manifold. We derive explicit error bounds that couple spatial discretization resolution with material data density. Numerical experiments using triaxial test data from a high-altitude region validate the theoretical predictions, showing that the proposed scheme demonstrates convergence in single-element tests.

Abstract RationaleClinical studies have revealed that methamphetamine abuse increases risk for developing Parkinson’s diseases. It is thus important to elucidate the mechanisms by which methamphetamine damages dopaminergic neurons.ObjectivesThe present study was designed to elucidate the role of the dopamine D1 receptor in methamphetamine-mediated dopaminergic neuronal damage and its underlying mechanisms.MethodsMice were treated for 4 days with vehicle, methamphetamine, or the D1 agonist SKF38393 and then assessed for locomotion and performance in the pole and rotarod tests. Cellular indices of autophagy, LC3, P62, and Beclin-1, tyrosine hydroxylase, and the AMPK/FOXO3A pathway were analyzed in striatal tissue from treated mice, in PC12 cells, and in D1 receptor mutant mice.ResultsRepeated treatment with a relatively high dose of methamphetamine for 4 days induced both loss of dopaminergic neurons and activation of autophagy in the striatum as evidenced by increased expression of LC3 and P62. However, such treatment did not induce either loss of dopaminergic neurons or activation of autophagy in D1 receptor knockout mice. D1 receptor-mediated activation of autophagy was also confirmed in vitro using dopaminergic neuronal PC12 cells. Further studies demonstrated that the AMPK/FOXO3A signaling pathway is responsible for D1 receptor-mediated activation of autophagy.ConclusionsThe present data indicate a novel mechanism for methamphetamine-induced dopaminergic neuronal damage and reveal an important role for D1 receptors in the neurotoxicity of this drug.

The objective of this study is to explore the antiproliferative activity of the traditional Chinese medicine monomer vitexin on colon cancer HCT-116 cells and its underlying mechanism. The in vitro antiproliferative activity of vitexin on colon cancer HCT-116 cells was evaluated using the CCK-8 assay. Potential drug targets for colon cancer were identified through GEO chip data mining, and molecular docking using Schrödinger software was conducted. Molecular dynamics simulations were employed to deeply analyze the interaction between candidate compounds and target proteins. Flow cytometry was employed to examine the cell cycle. The impact of vitexin on the expression of CDK1/cyclinB proteins in HCT-116 cells was assessed through Western blot analysis, immunofluorescence, and CDK inhibition assay. Vitexin exhibited inhibitory effects on colon cancer HCT-116 cells, with a half inhibitory concentration (IC50) value of 203.27 ± 9.85 μmol/L. The analysis of differential gene expression in GEO and TCGA datasets, along with the GENECARD dataset of related disease genes, identified 91 disease targets, including “CDK1.” Vitexin induced cell cycle arrest in the G2/M phase of HCT-116 cells. Molecular docking revealed a strong interaction between Vitexin and CDK1 (Docking score − 9.497), with molecular dynamics simulations confirming the stability of the Vitexin-CDK1 complex and comparable inhibitory effects to Flavopiridol. Vitexin can inhibit the expression of CDK1/cyclin B proteins in HCT-116 cells, with an IC50 of 58.06 ± 3.07 μmol/L. Vitexin may inhibit colon cancer HCT-116 cell proliferation by suppressing CDK1/cyclin B expression, leading to cell cycle arrest in the G2/M phase.

The safety of the cofferdam structure is of great significance for ensuring the smooth construction of dams, but the construction of cofferdams also faces significant safety risks. This article conducts three-dimensional finite element static calculation and analysis on the upstream cofferdam of Kala Hydropower Station. The calculation results show that the partition design of the cofferdam section is reasonable. The existing cofferdam construction plan is safe and feasible. When the top of the cofferdam flows for the second time, the stress and deformation of both the cofferdam body and the concrete impermeable wall will reach their maximum values and meet the requirements of the specifications. The maximum settlement of the dam body is 23.6cm, accounting for 0.4% of the maximum dam height. The maximum horizontal displacement downstream in the river direction is 20.4cm. The extreme values of the first and third main stresses are 1.36 MPa and 0.58 MPa, respectively. The shear stress level of each working condition is always less than 1. The concrete anti-seepage wall has a small tensile stress zone at the bottom due to slight deformation, but it is still within the tensile strength range of the concrete. The conclusion can provide a reference for the design and construction of similar cofferdam projects.

We report laboratory experiments to investigate the dynamic failure characteristics of outburst‐prone coal using a split Hopkinson pressure bar (SHPB). For comparison, two groups of experiments are completed on contrasting coals—the first outburst‐prone and the second outburst‐resistant. The dynamic mechanical properties, failure processes, and energy dissipation of both outburst‐prone and outburst‐resistant coals are comparatively analyzed according to the obtained dynamic compressive and tensile stress‐strain curves. Results show that the dynamic stress‐strain response of both outburst‐prone and outburst‐resistant coal specimens comprises stages of compression, linear elastic deformation, then microfracture evolution, followed by unstable fracture propagation culminating in rapid unloading. The mechanical properties of both outburst‐prone and outburst‐resistant coal specimens exhibit similar features: The uniaxial compressive strength and indirect tensile strength increase linearly with the applied strain rate, and the peak strain increases nonlinearly with the strain rate, whereas the elastic modulus does not exhibit any clear strain rate dependency. Differences in the dynamic failure characteristics between outburst‐prone and outburst‐resistant coals also exist. The hardening effect of strain rate on outburst‐prone coal is more apparent than on outburst‐resistant coal, which is reflected in the dynamic increase factor at the same strain rate. However, the dynamic strength of outburst‐prone coals is still lower than that of outburst‐resistant coals due to its low quasi‐static strength. The dissipated energy of outburst‐prone coal is smaller than that of outburst‐resistant coal. Therefore, the outburst‐prone coal, characterized by low strength, high deformability, and small energy dissipation when dynamically loaded to failure, is more favorably disposed to the triggering and propagation of gas outbursts. We report laboratory experiments to investigate the dynamic failure characteristics of outburst‐prone coal using a split Hopkinson pressure bar (SHPB). The dynamic mechanical properties, dynamic increase factor, failure processes, and energy dissipation of both outburst‐prone and outburst‐resistant coals are obtained and comparatively analyzed.

The strong nonlinearity of shallow-water waves significantly affects the dynamic response of floating offshore wind turbines (FOWTs), introducing additional complexity in motion behavior. This study presents a series of 1:80-scale experiments conducted on a 5 MW FOWT at a 50 m water depth, under regular, irregular, and focused wave conditions. The tests were conducted under regular, irregular, and focused wave conditions. The results show that, under both regular and irregular wave conditions, the platform’s motion and mooring tension increased as the wave period became longer, indicating a greater energy transfer and stronger coupling effects at lower wave frequencies. Specifically, in irregular seas, mooring tension increased by 16% between moderate and high sea states, with pronounced surge–pitch coupling near the natural frequency. Under focused wave conditions, the platform experienced significant surge displacement due to the impact of large wave crests, followed by free-decay behavior. Meanwhile, the pitch amplitude increased by up to 27%, and mooring line tension rose by 16% as the wave steepness intensified. These findings provide valuable insights for the design and optimization of FOWTs in complex marine environments, particularly under extreme wave conditions. Additionally, they contribute to the refinement of relevant numerical simulation methods.

Coal and gas outburst is a complex dynamic disaster during coal underground mining. Revealing the disaster mechanism is of great significance for accurate prediction and prevention of coal and gas outburst. The geo-dynamic system of coal and gas outburst is proposed. The framework of geo-dynamic system is composed of gassy coal mass, geological dynamic environment and mining disturbance. Equations of stress–damage–seepage interaction for gassy coal mass is constructed to resolve the outburst elimination process by gas extraction with boreholes through layer in floor roadway. The results show the occurrence of outburst is divided into the evolution process of gestation, formation, development and termination of geo-dynamic system. The scale range of outburst occurrence is determined, which provides a spatial basis for the prevention and control of outburst. The formation criterion and instability criterion of coal and gas outburst are established. The formation criterion F 1 is defined as the scale of the geo-dynamic system, and the instability criterion F 2 is defined as the scale of the outburst geo-body. According to the geo-dynamic system, the elimination mechanism of coal and gas outburst—‘unloading + depressurization’ is established, and the gas extraction by boreholes through layer in floor roadway for outburst elimination is given. For the research case, when the gas extraction is 120 days, the gas pressure of the coal seam is reduced to below 0.4 MPa, and the outburst danger is eliminated effectively.

Checkpoint blockade therapy targeting the programmed-death ligand 1 (PD-L1) and its receptor programmed cell death 1 promotes T-cell-mediated immunosurveillance against tumours, and has been associated with marked clinical benefit in cancer patients. Antibodies against PD-L1 function by blocking PD-L1 on the cell surface, but intracellular storage of PD-L1 and its active redistribution to the cell membrane can minimize the therapeutic benefits, which highlights the importance of targeting PD-L1 throughout the whole cell. Here, we show that PD-L1 is palmitoylated in its cytoplasmic domain, and that this lipid modification stabilizes PD-L1 by blocking its ubiquitination, consequently suppressing PD-L1 degradation by lysosomes. We identified palmitoyltransferase ZDHHC3 (DHHC3) as the main acyltransferase required for the palmitoylation of PD-L1, and show that the inhibition of PD-L1 palmitoylation via 2-bromopalmitate, or the silencing of DHHC3, activates antitumour immunity in vitro and in mice bearing MC38 tumour cells. We also designed a competitive inhibitor of PD-L1 palmitoylation that decreases PD-L1 expression in tumour cells to enhance T-cell immunity against the tumours. These findings suggest new strategies for overcoming PD-L1-mediated immune evasion in cancer. The physiological degradation of programmed-death ligand 1 is reduced by the palmitoylation of its intracellular domain, and this process can be inhibited to promote T-cell immunity against tumours.

This study provides a comprehensive analysis of seismic activity and structural characteristics in Shandong Province, China, with a focus on identifying seismic belts and potential epicentral zones critical for regional seismic safety. A detailed database was developed, integrating regional seismicity statistics, earthquake distribution patterns, significant geotectonic movements, and recent neotectonic activities. The results reveal that seismic activity in Shandong is heterogeneously distributed, with moderate to strong earthquakes predominantly associated with active fault zones and exhibiting zonal clustering. Earthquakes are generally shallow, occurring within the middle to upper crust, with historical destructive events averaging a focal depth of 19 km, while recent minor seismic events average 14.9 km in depth. These activities span North China Plain and Tan-Lu Seismic Statistical Areas. Projections indicate sustained or heightened seismic activity over the next century, with the potential for earthquakes up to magnitude 5. The geological framework is dominated by Luxi Fault Block and Tan-Lu Fault Zone, characterized by episodic uplift and subsidence driven by neotectonic movements. The prevailing horizontal tectonic stress regime supports the likelihood of strike-slip faulting as the predominant mechanism.