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A Mg-19Gd binary alloy with exceptionally good synergy of strength and ductility has been fabricated by conventional hot extrusion and aging. The aged alloy with a specific bimodal-grained structure achieves a yield strength of 482 MPa and an ultimate tensile strength of 535 MPa with a good elongation of 5%. The high strength arises from the high number density of β′ precipitates and a strong texture, while the good ductility is related to the excellent deformation ability of fine dynamic recrystallized grains and the compatible ability of slips within elongated grains, activated by the high density of I1 stacking faults inside.

Cholangiocarcinoma is one of the most lethal human cancers, and chemotherapy failure is a major cause of recurrence and poor prognosis. We previously demonstrated that miR-200 family members are downregulated in clinical samples of cholangiocarcinoma and inhibit cholangiocarcinoma tumorigenesis and metastasis. However, the role of differentially expressed miR-200b-3p in 5-fluorouracil chemosensitivity remains unclear. Here, we examined how miR-200b-3p modulates 5-fluorouracil chemosensitivity in cholangiocarcinoma. We observed that miR-200b-3p was associated with 5-fluorouracil sensitivity in cholangiocarcinoma and increased 5-fluorouracil-induced mitochondrial apoptosis in cholangiocarcinoma cells. Mechanistically, miR-200b-3p suppressed autophagy in cholangiocarcinoma cells to mediate 5-fluorouracil sensitivity. Further, we identified KLF4 as an essential target of miR-200b-3p in cholangiocarcinoma. Notably, the miR-200b-3p/KLF4/autophagy pathway augmented the chemosensitivity of cholangiocarcinoma cells to 5-fluorouracil. Our findings underscore the key role of miR-200b-3p in chemosensitivity to 5-fluorouracil and highlight the miR-200b-3p/KLF4/autophagy axis as a potential therapeutic target for cholangiocarcinoma.

Abstract Magnetic pulse spot welding based on a field shaper can effectively achieve spot welding of dissimilar metal plates by using the multi-turn flat coil and magnetic gathering through the field shaper. Through existing experimental research, it has been found that when using this method for welding, there will be a serious bulging problem in the center of the welding area, which will affect the flatness and aesthetics of the welding area, thereby affecting its application range. To solve this problem, this work proposes two different welding methods for welding dissimilar AA1060 aluminum and SS304 steel plates with a thickness of 1 mm: one based on the center opening of the flying plate and the other based on the pre-deformation of the flying plate. The causes of bulging and the effects of discharge voltage, welding gap, and inner hole radius of the field shaper on bulging size were studied. The cross-sectional morphology and mechanical properties of welded joints obtained by two welding methods were studied through numerical simulation, cross-sectional analysis, and tensile testing. The results indicated that both welding methods can successfully eliminate the bulging problem, and the point welding method based on the center opening of the aluminum plate can also reduce the minimum welding energy required for effective welding and improve welding efficiency. In addition, microscopic analysis results showed that a waveform composite interface was formed at the welding interface of the joint, and the connection performance of the welded joint was good. These two welding methods can also be extended to the welding of other dissimilar metal plates, which is of great significance for the industrial application of magnetic pulse spot welding technology based on field shaper.

Abstract Urea’s transmembrane transport through urea transporters (UT) is a fundamental physiological behavior for life activities. Here, we present 11 cryo-EM structures of four UT members in resting states, urea transport states, or inactive states bound with synthetic competitive, uncompetitive or noncompetitive inhibitor. Our results indicate that the binding of urea via a conserved urea recognition motif (URM) and the urea transport via H-bond transfer along the QPb-T5b-T5a-QPa motif among different UT members. Moreover, distinct binding modes of the competitive inhibitors 25a and ATB3, the uncompetitive inhibitor CF11 and the noncompetitive inhibitor HQA2 provide different mechanisms for blocking urea transport and achieved selectivity through L-P pocket, UCBP region and SCG pocket, respectively. In summary, our study not only allows structural understanding of urea transport via UTs but also afforded a structural landscape of hUT-A2 inhibition by competitive, uncompetitive and noncompetitive inhibitors, which may facilitate developing selective human UT-A inhibitors as a new class of salt-sparing diuretics.

Abstract Under asymmetric three-dimensional high in-situ stress and high pore water pressure, tunnels are subjected to complex stress conditions, making them susceptible to failure and posing a threat to water conveyance safety. This study focuses on a large-scale cross-basin water diversion tunnel from Datong river into Huangshui river, which characterized by ultra-deep and complex geological conditions. Based on the field measurement data, a parameter inversion method considering the deformation of tunnel surrounding rock at multiple characteristic points is proposed. Additionally, considering the fluid-structure interaction effects under the influence of asymmetrical three-dimensional high in-situ stress and high pore water pressure, the stress-deformation characteristics of the soft rock tunnel are studied, and the damage evolution characteristics of the surrounding rock under different in-situ stresses and pore water pressures are analyzed. The results manifest that intense mutual extrusion of the surrounding rock, leading to volumetric compression, is the primary cause of the formation of stress concentration and excess pore water pressure. Additionally, the maximum deformation and the most likely location for gushing water both occur at the tunnel’s waist. After the implementation of segment support measures, the deformation control effect on the surrounding rock is remarkable. Notably, the reduction in damage depth across various characteristic locations due to segment support shows minimal variation. However, in terms of the reduction in disturbance depth, the tunnel waist significantly outperforms the top and bottom positions. The damage depth of the tunnel surrounding rock is positively correlated with both in-situ stress and pore water pressure, but it is more significantly influenced by in-situ stress than by pore water pressure. These findings can offer some valuable insights and guidance for future similar tunnel construction project.

In this work, we compared the effects of bimodal microstructure and heterogeneous microstructure on the mechanical properties and strengthening mechanisms of ZK60 alloy. The bimodal microstructure is composed of coarse un-dynamically recrystallized (un-DRXed) grains with strong basal texture and fine dynamically recrystallized (DRXed) grains with weak texture, while the heterogeneous microstructure is composed of coarse DRXed grains and fine DRXed grains. The result suggests that high-density dislocations and high-density precipitates have significant contribution to the strength. The high-density dislocations in un-DRXed grains cause the formation of an uneven distribution of precipitates in the ZK60 alloy which results in the high yield strength of 305 MPa, ultimate tensile strength of 344 MPa and elongation of 12% in the bimodal-structured ZK60 alloy. In comparison, the heterogeneous-structured ZK60 alloy lacks the strengthening effect from high-density dislocations and precipitates, and a lower YS of 226 MPa, and UTS of 305 MPa are achieved. The result also indicates the weak texture, low density of dislocations, low density of precipitates, and stronger ability of storing dislocations in coarse grains for heterogeneous microstructure are helpful to the ductility. Thus, HE sample exhibits higher elongation of 23% than BI sample. The finding shed light on the microstructure designing of high-performance Mg alloys.

Abstract Circulating miR-30c-2-3p has been closely related to vascular diseases, however, its role and underlying mechanisms in ischemic stroke remained unclear. Our study addressed this gap by observing elevated levels of exosomal miR-30c-2-3p in patients with acute ischemic stroke due to large artery atherosclerosis. Further investigation revealed that these exosomal miR-30c-2-3p primarily originated from macrophages within atherosclerotic plaques, exacerbating ischemic stroke by targeting microglia. Exosomes enriched with miR-30c-2-3p increased microglial inflammatory properties in vivo and aggravated neuroinflammation by inhibiting SMAD2. In summary, our findings revealed a novel mechanism whereby macrophage-derived foam cells within atherosclerotic plaques secrete exosomes with high levels of miR-30c-2-3p, thus aggravate brain damage during ischemic stroke, which serves as crucial link between the periphery and brain.

Abstract The present study was conducted to observe the protective effects of c9, t11- conjugated linoleic acid (CLA) on oxidative stress and inflammation in bovine mammary epithelial cells (BMECs) exposed to H2O2. The BMECs were treated with different concentrations of H2O2 for 8 h, 600 µmol/L was determined to be the damage concentration. Using different concentrations of c9, t11-CLA to process BMECs for 24 h, 50 and 100 µmol/L were determined to be the effective concentrations for subsequent analyses. Thus, four BMEC groups were established: Control group; H2O2 group; 50 µmol/L c9, t11-CLA + H2O2 group; 100 µmol/L c9, t11-CLA + H2O2 group. We observed that the H2O2 group exhibited significantly lower total antioxidant activity (T-AOC), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activities and significantly higher secretions of malondialdehyde (MDA), interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor (TNF)-α and expressions of IL-1β, IL-6, and IL-8 than the control group (p

Bone defect repair remains a great challenge in the field of orthopedics. Human body essential trace element such as copper is essential for bone regeneration, but how to use it in bone defects and the underlying its mechanisms of promoting bone formation need to be further explored. In this study, by doping copper into mesoporous bioactive glass nanoparticles (Cu-MBGNs), we unveil a previously unidentified role of copper in facilitating osteoblast mitophagy and mitochondrial dynamics, which enhance amorphous calcium phosphate (ACP) release and subsequent biomineralization, ultimately accelerating the process of bone regeneration. Specifically, by constructing conditional knockout mice lacking the autophagy gene Atg5 in osteogenic lineage cells, we first confirmed the role of Cu-MBGNs-promoted bone formation via mediating osteoblast autophagy pathway. Then, the in vitro studies revealed that Cu-MBGNs strengthened mitophagy by inducing ROS production and recruiting PINK1/Parkin, thereby facilitating the efficient release of ACP from mitochondria into matrix vesicles for biomineralization during bone regeneration. Moreover, we found that Cu-MBGNs promoted mitochondrion fission via activating dynamin related protein 1 (Drp1) to reinforce mitophagy pathway. Together, this study highlights the potential of Cu-MBGNs‐mediated mitophagy and biomineralization for augmenting bone regeneration, offering a promising avenue for the development of advanced bioactive materials in orthopedic applications.

The application of copper azole (CA) preservative on glulam can improve the durability of the material. The effect of CA preservative was evaluated relative to the surface bonding quality of laminates with different surface conditions. The surface morphology and wettability of CA preservative-treated laminates were analyzed. A comparison was made on the interlaminar shear strength of preservative-treated glulam under varying environmental conditions. The atomic force microscope (AFM) diagrams showed that CA preservative adhered to the wood fibers’ surface and filled some wood cell cavities, thus reducing the water permeability of the treated laminate. Planing effectively enhanced the surface wettability of the preservative-treated laminate. The tiny particles of CA preservative on the planed laminate surface were distributed relatively uniformly, with a proportion smaller than that of the unplaned laminate. Furthermore, the interlaminar shear strength of preservative-treated glulam using planed laminates was at least 15% higher than that of unplaned laminates. In both hot and humid environments and natural aging tests, preservative-treated glulam bonded with resorcinol formaldehyde (RF) adhesive outperformed those bonded with polyurethane (PUR) adhesive. To ensure reliable quality of preservative-treated glulam, it is recommended to plane the laminate by 0.6 mm and use RF adhesive.

Purpose – This study aimed to facilitate a rapid evaluation of track service status and vehicle ride comfort based on car body acceleration. Consequently, a low-cost, data-driven approach was proposed for analyzing speed-related acceleration limits in metro systems. Design/methodology/approach – A portable sensing terminal was developed to realize easy and efficient detection of car body acceleration. Further, field measurements were performed on a 51.95-km metro line. Data from 272 metro sections were tested as a case study, and a quantile regression method was proposed to fit the control limits of the car body acceleration at different speeds using the measured data. Findings – First, the frequency statistics of the measured data in the speed-acceleration dimension indicated that the car body acceleration was primarily concentrated within the constant speed stage, particularly at speeds of 15.4, 18.3, and 20.9 m/s. Second, resampling was performed according to the probability density distribution of car body acceleration for different speed domains to achieve data balance. Finally, combined with the traditional linear relationship between speed and acceleration, the statistical relationships between the speed and car body acceleration under different quantiles were determined. We concluded the lateral/vertical quantiles of 0.8989/0.9895, 0.9942/0.997, and 0.9998/0.993 as being excellent, good, and qualified control limits, respectively, for the lateral and vertical acceleration of the car body. In addition, regression lines for the speed-related acceleration limits at other quantiles (0.5, 0.75, 2s, and 3s) were obtained. Originality/value – The proposed method is expected to serve as a reference for further studies on speed-related acceleration limits in rail transit systems.

Objective:. The Pulmonary Arterial Denervation in Patients With Pulmonary Hypertension Associated With the Left Heart Failure (PADN-5) study proved that pulmonary artery denervation (PADN) is associated with significant improvements in hemodynamic and clinical outcomes in patients with combined pre- and post-capillary pulmonary hypertension (CpcPH). This study aimed to assess the 3-year clinical results of PADN in patients who had heart failure with preserved ejection fraction (HFpEF) developing into CpcPH (HFpEF-CpcPH). Methods:. In this post hoc analysis of the PADN-5 trial, 38 patients with HFpEF were included in screening out of 98 patients with CpcPH who were randomly assigned to treatment with sildenafil and sham PADN (sham PADN (plus sildenafil) group, abbreviated as sham group) or PADN (PADN group). HFpEF in the PADN-5 trial was defined as a left ventricular ejection fraction ≥50%, and CpcPH was defined as a mean pulmonary arterial pressure ≥25 mmHg, a pulmonary arterial wedge pressure >15 mmHg, and a pulmonary vascular resistance >3.0 WU. The changes in the 6-minute walk distance (6-MWD) and the plasma concentration of N-terminal pro-brain natriuretic peptide (NT-proBNP) at 6-month and 3-year follow-up, as well as the clinical endpoint of the occurrence of clinical worsening, defined as cardiopulmonary-related death, rehospitalization, or heart or lung transplantation at 3-year follow-up were examined. Results:. Thirty-eight patients with HFpEF-CpcPH were assigned to the PADN group (n = 19) or the sham group (n = 19). At the 6-month follow-up, 6-MWD (433 (275, 580)m vs. 342 (161, 552)m), and reductions in NT-proBNP (−47% (−99%, 331%) vs. −12% (−82%, 54%)) were significantly improved in the PADN group (all P < 0.05). Over the 3-year follow-up period, PADN treatment resulted in marked increases in 6-MWD (450 (186, 510)m vs. 348 (135, 435)m) and reductions in NT-proBNP (−55% (−99%, 38%) vs. −10% (−80%, 95%)) (all P < 0.05). Clinical worsening was experienced by 12 patients (63%) in the sham group, but by only 5 patients (26%) in the PADN group (hazard ratio = 0.149, 95% confidence interval: 0.038–0.584, P = 0.006). The 6-MWD and PADN treatments were independent predictors of clinical deterioration in patients with HFpEF-CpcPH. Conclusions:. PADN therapy is associated with improvements in exercise capacity and clinical outcomes. PADN therapy may have a potential role in patients with HFpEF-CpcPH for whom current treatment options are limited.

Abstract Background Klotho plays a pivotal role in human aging. Metabolic syndrome (MetS) is composed of multiple conditions that are also risk factors for cardiovascular disease and diabetes. We try to discuss gender-specific differences in Klotho and the associations between Klotho and MetS components. Materials and methods The National Health and Nutrition Examination Survey database from cycle 2015–2016 was analyzed. MetS was defined according to the 2005 updated criteria by the American Heart Association and National Heart Lung and Blood Institute. Gender-specific differences in serum Klotho, and associations between Klotho level and MetS components were examined. Results A total of 2475 participants (40–79 years old) with comprehensive data were included (52% women). In general, lower Klotho was associated with advanced age, male sex, tobacco use, elevated triglycerides, renal insufficiency, inflammation, low estradiol, and low sex hormone-binding globulin (SHBG). The correlation between MetS and Klotho was more obvious in women, mainly in waist circumference and triglyceride. There were no gender-specific differences in the associations between Klotho and renal dysfunction, but multivariate linear regression analysis showed gender differences in other factors associated with Klotho. Estradiol, SHBG, high-density lipoprotein cholesterol (HDL), and high-sensitivity C-reactive protein (CRP) were associated with Klotho levels independent of age and renal function in men, whereas in women, Klotho was independently associated with triglycerides and white blood cell count. Conclusion Klotho levels had gender disparities regardless of age, renal function, and sex hormones. In the current cohort, triglycerides were the major component of MetS that was independently associated with serum Klotho levels, and the association was particularly seen in women. However, HDL was found to be the male-specific MetS component independently associated with Klotho.

Automated pavement condition survey is of critical importance to road network management. There are three primary tasks involved in pavement condition surveys, namely data collection, data processing and condition evaluation. Artificial intelligence (AI) has achieved many breakthroughs in almost every aspect of modern technology over the past decade, and undoubtedly offers a more robust approach to automated pavement condition survey. This article aims to provide a comprehensive review on data collection systems, data processing algorithms and condition evaluation methods proposed between 2010 and 2023 for intelligent pavement condition survey. In particular, the data collection system includes AI-driven hardware devices and automated pavement data collection vehicles. The AI-driven hardware devices including right-of-way (ROW) cameras, ground penetrating radar (GPR) devices, light detection and ranging (LiDAR) devices, and advanced laser imaging systems, etc. These different hardware components can be selectively mounted on a vehicle to simultaneously collect multimedia information about the pavement. In addition, this article pays close attention to the application of artificial intelligence methods in detecting pavement distresses, measuring pavement roughness, identifying pavement rutting, analyzing skid resistance and evaluating structural strength of pavements. Based upon the analysis of a variety of the state-of-the-art artificial intelligence methodologies, remaining challenges and future needs with respect to intelligent pavement condition survey are discussed eventually.

In this work, the influence of Mn and Ca doping on the microstructure and mechanical properties of Mg–3Zn, Mg–3Zn-0.5Mn, and Mg–3Zn-0.5Mn-1.2Ca alloys is systematically investigated. The addition of Mn elements is shown to exert no obvious effect on the microstructure of as-cast, as-homogenized, and extruded Mg–3Zn alloys. In contrast, the introduction of Ca into the extruded Mg–3Zn-0.5Mn alloy promotes the formation of nano-sized compounds and enhances grain refinement compared to the other two alloys. The extruded Mg–3Zn-0.5Mn alloy exhibits the higher yield strength (YS, 155 MPa) and ultimate tensile strength (UTS, 183 MPa) but the lower elongation (13%) than the extruded Mg–3Zn alloy (YS of 130 MPa, UTS of 175 MPa, and elongation of 25%). The improved strength of the extruded Mg–3Zn-0.5Mn alloy is mainly attributed to the refined grains, while both the lack of twinning deformation and strong texture result in ductility loss. The most optimal combination of strength and ductility is achieved in an extruded Mg–3Zn-0.5Mn-1.2Ca alloy (YS of 180 MPa, UTS of 250 MPa, and elongation of 26%). This suggests that fine grains and high volume fraction of nano-sized MgZn2 compounds contribute mainly to the strength of Mg–3Zn-0.5Mn-1.2Ca alloy. Although the grain refinement also facilitates the suppression of twinning in the extruded Mg–3Zn-0.5Mn-1.2Ca alloy, the weak texture and fine homogeneous grains are conducive to the high ductility.

The coordinated arrangement of gas pre-drainage boreholes and anti-impact and pressure relief boreholes can integrate the prevention and control of mine rock burst and gas compound disasters. However, the dense arrangement of these boreholes may lead to the occurrence of phenomena such as string holes and collapse holes, which could potentially impact the efficiency of mine gas extraction. To investigate the deformation around borehole surface and the evolution of fractures during the compression failure process in the coal and rock masses with dual borehole structure, the 3D-DIC observation experiment was conducted on the coal samples containing double circular holes under uniaxial compression conditions using a digital image observation system for coal rock deformation and failure. This experiment yielded some time-series images of sample surface deformation under various stress states. The three-dimensional full-field deformation of the sample surface was calculated using the three-dimensional surface reconstruction technology and VIC3D analysis processing software. Based on the results of strain field analysis, the stress-strain curve was divided into five deformation stages using statistical index analysis methods, providing a detailed description of the deformation and fracture evolution characteristics around the borehole surface. The results show that under uniaxial compression, the grayscale of strain field in the coal samples with double circular holes shifts toward higher gray levels. The proportion of peaks in the strain field gray histogram changes slowly at first and then rapidly, with the peak stress serving as the boundary. The radial displacement curve around the sample holes presents a “从” shape, while the circumferential displacement curve presents a “人” shape. The left hole H1 always accelerates counterclockwise, while the right hole H2 always accelerates clockwise. The fractures around the holes are primarily characterized by counterclockwise dislocation, accompanied by a few instances of clockwise dislocation. The outer zone of strain localization primarily exhibits energy accumulation before the loading peak and energy release after the loading peak. This is accompanied by energy accumulation resulting from partial energy adjustment and transfer. During the loading process of the specimen, the factors such as the stress field environment, the geometry of fracture end, and the length of fracture undergo constant changes. This results in a reduction in the stress intensity factor KⅠ at the tip of the fracture, thereby impeding the expansion of the fracture.

Abstract In today’s globalized agricultural system, information leakage of agricultural biological risk factors can lead to business risks and public panic, jeopardizing corporate reputation. To solve the above problems, this study constructs a blockchain network for agricultural product biological risk traceability based on agricultural product biological risk factor data to achieve traceability of biological risk traceability data of agricultural product supply chain to meet the sustainability challenges. To guarantee the secure and flexible sharing of agricultural product biological risk privacy information and limit the scope of privacy information dissemination, the blockchain-based proxy re-encryption access control method (BBPR-AC) is designed. Aiming at the problems of proxy re-encryption technology, such as the third-party agent being prone to evil, the authorization judgment being cumbersome, and the authorization process not automated, we design the proxy re-encryption access control mechanism based on the traceability of agricultural products’ biological risk factors. Designing an attribute-based access control (ABAC) mechanism based on the traceability blockchain for agricultural products involves defining the attributes of each link in the agricultural supply chain, formulating policies, and evaluating and executing these policies, deployed in the blockchain system in the form of smart contracts. This approach achieves decentralization of authorization and automation of authority judgment. By analyzing the data characteristics within the agricultural product supply chain to avoid the malicious behavior of third-party agents, the decentralized blockchain system acts as a trusted third-party agent, and the proxy re-encryption is combined with symmetric encryption to improve the encryption efficiency. This ensures a efficient encryption process, making the system safe, transparent, and efficient. Finally, a prototype blockchain system for traceability of agricultural biological risk factors is built based on Hyperledger Fabric to verify this research method’s reliability, security, and efficiency. The experimental results show that this research scheme’s initial encryption, re-encryption, and decryption sessions exhibit lower computational overheads than traditional encryption methods. When the number of policies and the number of requests in the access control session is 100, the policy query latency is less than 400 ms, the request-response latency is slightly more than 360ms, and the data uploading throughput is 48.7 tx/s. The data query throughput is 81.8 tx/s, the system performance consumption is low and can meet the biological risk privacy protection needs of the agricultural supply chain. The BBPR-AC method proposed in this study provides ideas for achieving refined traceability management in the agricultural supply chain and promoting digital transformation in the agricultural industry.

Abstract Background Widespread neuropathic pain usually affects a wide range of body areas and inflicts huge suffering on patients. However, little is known about how it happens and effective therapeutic interventions are lacking. Methods Widespread neuropathic pain was induced by partial infraorbital nerve transection (p-IONX) and evaluated by measuring nociceptive thresholds. In vivo/vitro electrophysiology were used to evaluate neuronal activity. Virus tracing strategies, combined with optogenetics and chemogenetics, were used to clarify the role of remodeling circuit in widespread neuropathic pain. Results We found that in mice receiving p-IONX, along with pain sensitization spreading from the orofacial area to distal body parts, glutamatergic neurons in the ventral posteromedial nucleus of the thalamus (VPMGlu) were hyperactive and more responsive to stimulations applied to the hind paw or tail. Tracing experiments revealed that a remodeling was induced by p-IONX in the afferent circuitry of VPMGlu, notably evidenced by more projections from glutamatergic neurons in the dorsal column nuclei (DCNGlu). Moreover, VPMGlu receiving afferents from the DCN extended projections further to glutamatergic neurons in the posterior insular cortex (pIC). Selective inhibition of the terminals of DCNGlu in the VPM, the soma of VPMGlu or the terminals of VPMGlu in the pIC all alleviated trigeminal and widespread neuropathic pain. Conclusion These results demonstrate that hyperactive VPMGlu recruit new afferents from the DCN and relay the extra-cephalic input to the pIC after p-IONX, thus hold a key position in trigeminal neuropathic pain and its spreading. This study provides novel insights into the circuit mechanism and preclinical evidence for potential therapeutic targets of widespread neuropathic pain.

Abstract Background Radiotherapy is one of the main treatments for cervical cancer. Long-term complications of radiation exposure include the emergence of secondary tumors. This is a retrospective study based on an American population. We discuss the optimal treatment modality for patients with radiation-induced secondary uterine malignancy based on the Surveillance, Epidemiology, and End Results database. Methods The study included patients with a definitive pathological diagnosis of cervical cancer who were diagnosed with a uterine malignant tumor ≥ 1 year later. Patients in whom cervical cancer was not the first tumor or patients with missing data were excluded. Univariate and multivariate analyses were performed using the COX regression model to screen independent prognostic factors affecting overall survival. Kaplan-Meier survival curves were analyzed using the R software package. Results We screened 142 patients with a secondary uterine malignancy after cervical cancer treatment, 115 patients with a secondary uterine malignancy after radiotherapy, and 27 patients with a secondary uterine malignancy who did not receive radiotherapy. The average latency period for developing a secondary tumor was 8 years, and 57.04% of the patients had a second tumor at ≥ 60 years of age. In patients with a secondary uterine malignancy after radiotherapy, surgery improved the prognosis [hazard ratio (HR), 0.374; 95% confidence interval (CI), 0.229–0.612], whereas radiotherapy and chemotherapy did not reduce the risk of death. In the subgroup analysis, the surgery plus chemotherapy group had a significantly better survival prognosis than the other groups (HR, 0.251; 95% CI, 0.122–0.515). Conclusions The results suggest that the treatment modality in patients with secondary uterine malignancy after radiotherapy for cervical cancer has a significant impact on survival. The survival outcomes of patients receiving surgery combined with chemotherapy are superior to those of patients receiving other treatments.

Abstract Robot-assisted surgery has evolved into a crucial treatment for prostate cancer (PCa). However, from its appearance to today, brain-computer interface, virtual reality, and metaverse have revolutionized the field of robot-assisted surgery for PCa, presenting both opportunities and challenges. Especially in the context of contemporary big data and precision medicine, facing the heterogeneity of PCa and the complexity of clinical problems, it still needs to be continuously upgraded and improved. Keeping this in mind, this article summarized the 5 stages of the historical development of robot-assisted surgery for PCa, encompassing the stages of emergence, promotion, development, maturity, and intelligence. Initially, safety concerns were paramount, but subsequent research and engineering advancements have focused on enhancing device efficacy, surgical technology, and achieving precise multi modal treatment. The dominance of da Vinci robot-assisted surgical system has seen this evolution intimately tied to its successive versions. In the future, robot-assisted surgery for PCa will move towards intelligence, promising improved patient outcomes and personalized therapy, alongside formidable challenges. To guide future development, we propose 10 significant prospects spanning clinical, research, engineering, materials, social, and economic domains, envisioning a future era of artificial intelligence in the surgical treatment of PCa.

Abstract Photoacoustic tomography offers a powerful tool to visualize biologically relevant molecules and understand processes within living systems at high resolution in deep tissue, facilitated by the conversion of incident photons into low-scattering acoustic waves through non-radiative relaxation. Although current endogenous and exogenous photoacoustic contrast agents effectively enable molecular imaging within deep tissues, their broad absorption spectra in the visible to near-infrared (NIR) range limit photoacoustic multiplexed imaging. Here, we exploit the distinct ultrasharp NIR absorption peaks of lanthanides to engineer a series of NIR photoacoustic nanocrystals. This engineering involves precise host and dopant material composition, yielding nanocrystals with sharply peaked photoacoustic absorption spectra (~3.2 nm width) and a ~10-fold enhancement in NIR optical absorption for efficient deep tissue imaging. By combining photoacoustic tomography with these engineered nanocrystals, we demonstrate photoacoustic multiplexed differential imaging with substantially decreased background signals and enhanced precision and contrast.

Abstract In the pursuit of scalable and energy-efficient neuromorphic devices, recent research has unveiled a novel category of spiking oscillators, termed “thermal neuristors.” These devices function via thermal interactions among neighboring vanadium dioxide resistive memories, emulating biological neuronal behavior. Here, we show that the collective dynamical behavior of networks of these neurons showcases a rich phase structure, tunable by adjusting the thermal coupling and input voltage. Notably, we identify phases exhibiting long-range order that, however, does not arise from criticality, but rather from the time non-local response of the system. In addition, we show that these thermal neuristor arrays achieve high accuracy in image recognition and time series prediction through reservoir computing, without leveraging long-range order. Our findings highlight a crucial aspect of neuromorphic computing with possible implications on the functioning of the brain: criticality may not be necessary for the efficient performance of neuromorphic systems in certain computational tasks.

Abstract Background Acute respiratory distress syndrome (ARDS) after cardiac surgery is a severe respiratory complication with high mortality and morbidity. Traditional clinical approaches may lead to under recognition of this heterogeneous syndrome, potentially resulting in diagnosis delay. This study aims to develop and external validate seven machine learning (ML) models, trained on electronic health records data, for predicting ARDS after cardiac surgery. Methods This multicenter, observational cohort study included patients who underwent cardiac surgery in the training and testing cohorts (data from Nanjing First Hospital), as well as those patients who had cardiac surgery in a validation cohort (data from Shanghai General Hospital). The number of important features was determined using the sliding windows sequential forward feature selection method (SWSFS). We developed a set of tree-based ML models, including Decision Tree, GBDT, AdaBoost, XGBoost, LightGBM, Random Forest, and Deep Forest. Model performance was evaluated using the area under the receiver operating characteristic curve (AUC) and Brier score. The SHapley Additive exPlanation (SHAP) techinque was employed to interpret the ML model. Furthermore, a comparison was made between the ML models and traditional scoring systems. ARDS is defined according to the Berlin definition. Results A total of 1996 patients who had cardiac surgery were included in the study. The top five important features identified by the SWSFS were chronic obstructive pulmonary disease, preoperative albumin, central venous pressure_T4, cardiopulmonary bypass time, and left ventricular ejection fraction. Among the seven ML models, Deep Forest demonstrated the best performance, with an AUC of 0.882 and a Brier score of 0.809 in the validation cohort. Notably, the SHAP values effectively illustrated the contribution of the 13 features attributed to the model output and the individual feature's effect on model prediction. In addition, the ensemble ML models demonstrated better performance than the other six traditional scoring systems. Conclusions Our study identified 13 important features and provided multiple ML models to enhance the risk stratification for ARDS after cardiac surgery. Using these predictors and ML models might provide a basis for early diagnostic and preventive strategies in the perioperative management of ARDS patients.

Abstract Chronic cerebral hypoperfusion (CCH), a disease afflicting numerous individuals worldwide, is a primary cause of cognitive deficits, the pathogenesis of which remains poorly understood. Bruton’s tyrosine kinase inhibition (BTKi) is considered a promising strategy to regulate inflammatory responses within the brain, a crucial process that is assumed to drive ischemic demyelination progression. However, the potential role of BTKi in CCH has not been investigated so far. In the present study, we elucidated potential therapeutic roles of BTK in both in vitro hypoxia and in vivo ischemic demyelination model. We found that cerebral hypoperfusion induced white matter injury, cognitive impairments, microglial BTK activation, along with a series of microglia responses associated with inflammation, oxidative stress, mitochondrial dysfunction, and ferroptosis. Tolebrutinib treatment suppressed both the activation of microglia and microglial BTK expression. Meanwhile, microglia-related inflammation and ferroptosis processes were attenuated evidently, contributing to lower levels of disease severity. Taken together, BTKi ameliorated white matter injury and cognitive impairments induced by CCH, possibly via skewing microglia polarization towards anti-inflammatory and homeostatic phenotypes, as well as decreasing microglial oxidative stress damage and ferroptosis, which exhibits promising therapeutic potential in chronic cerebral hypoperfusion-induced demyelination.

The purpose of this study was to investigate the relationship between childhood chronic stress(CCS), Protein kinase C beta (PRKCB) methylation and adolescent major depressive disorder (MDD). After recruiting 100 adolescents with MDD and 50 healthy controls (HCs), we evaluated the severity of CCS. PRKCB methylation was assessed by pyrosequencing using whole blood-derived DNA. To explore the relationship between CCS, PRKCB and adolescent MDD, we conducted correlation analysis and regression analysis, and constructed multiplicative interaction models and generalized linear models. PRKCB methylation and CCS were both found to be associated with MDD, and CCS was associated with PRKCB methylation. No significant CCS-PRKCB methylation interactions were observed. However, we found the interaction of CCS and MDD on PRKCB methylation. Our results found that PRKCB methylation was influenced by CCS and the disease itself, and PRKCB methylation was significantly positively associated with MDD severity, suggesting that PRKCB methylation may be a potential biomarker for adolescent MDD. This study is a cross-sectional observational study, which cannot draw the conclusion of causality. Prospective cohort studies are needed to further examine the relationship between CCS, adolescent MDD, and PRKCB methylation.

Thin film solar cells often have high densities of dopants and native defects that result in carrier compensation and local electrostatic fields, which produce band edge fluctuations observable as tails in luminescence and absorption spectra. The analysis here shows that these fluctuations can reduce the open-circuit voltage (Voc) by tens to hundreds of millivolts and alter the Voc temperature coefficients. Although the extrapolation of Voc to 0 K is often used to gauge interface recombination, reductions in this value can also be explained by band edge fluctuations. In addition, these fluctuations can explain pronounced anomalous trends between carrier concentration and Voc in state-of-the-art CdSeTe:As solar cells, representing a significant departure from device models that do not include them. The analysis can be applied to other thin film technologies. To improve CdSeTe solar cell performance, it is critical to assess band edge fluctuations and address carrier compensation and defect chemistry to mitigate their impact.

Abstract Surface reconstruction plays an essential role in electrochemical catalysis. The structures, compositions, and functionalities of the real catalytic species and sites generated by reconstruction, however, are yet to be clearly understood, for the metastable or transit state of most reconstructed structures. Herein, a series of NiFe oxalates (NixFe1‐xC2O4, x = 1, 0.9, 0.7, 0.6, 0.5, and 0) are synthesized for overall water splitting electrocatalysis. Whilst NixFe1‐xC2O4 shows great hydrogen evolution reaction (HER) activity, the in situ reconstructed NixFe1‐xOOH exhibits outstanding oxygen evolution reaction (OER) activity. As identified by the in situ Raman spectroscopy and quasi‐in situ X‐ray absorption spectroscopy (XAS) techniques, reconstructions from NixFe1‐xC2O4 into defective NixFe1‐xOOH and finally amorphous NixFe1‐xOOH active species (R‐NixFe1‐xOOH) are confirmed upon cyclic voltammetry processes. Specifically, the fully reconstructed R‐Ni0.6Fe0.4OOH demonstrates the best OER activity (179 mV to reach 10 mA cm−2), originating from its abundant real active sites and optimal d‐band center. Benefiting from the reconstruction, an alkaline electrolyzer composed of a Ni0.6Fe0.4C2O4 cathode and an in situ reconstructed R‐Ni0.6Fe0.4OOH anode achieves a superb overall water splitting performance (1.52 V@10 mA cm−2). This work provides an in‐depth structure‐property relationship understanding on the reconstruction of catalysts and offers a new pathway to designing novel catalyst.

Abstract Molecular targeted tyrosine kinase inhibitors (TKIs) have produced unprecedented treatment response in cancer therapy for patients harboring specific oncogenic mutations. While the TKIs are mostly well tolerated, they were reported to increase serum levels of creatine kinase (CK) and cause muscle metabolism‐related toxicity. CK is an essential enzyme involved in cellular energy metabolism and muscle function. Elevated serum CK levels can arise from both physiological and pathological factors, as well as triggered by specific drug classes. The incidence of serum CK elevation induced by a few approved TKIs (brigatinib, binimetinib, cobimetinib‐vemurafenib combination [Food and Drug Administration, United States]; aumolertinib, and sunvozertinib [only approved by National Medical Products Administration, China]) were over 35%. CK elevation‐related symptoms include myopathy, myositis, inclusion body myositis (IBM), cardiotoxicity, rhabdomyolysis, rash, and acneiform dermatitis. High‐level or severe symptomatic CK elevation may necessitate dose reduction and indirectly dampen TKI efficacy. This review presents an updated summary about the prevalence rate and recent research about mechanisms leading to TKI‐induced serum CK elevation in cancer patients. The utility of monitoring serum CK levels for predicting TKI‐induced adverse effects and their management will also be discussed.

Abstract The concept of ferroelectric polarons is proposed to partially explain the exceptional optoelectronic properties observed in lead halide perovskites (LHPs). It is intriguing but unclear how this proposal, which involves local or transient polarizations, applies in general to 2D LHPs with long‐range ferroelectricity. Here, this work presents a pioneering time‐domain experimental investigation of polarons in ferroelectric (IA)2(MA)2Pb3Br10 (IMPB; IA is isoamylammonium and MA is methylammonium) using transient absorption spectroscopy. Compared to non‐ferroelectric LHPs, IMPB exhibits several distinct polaronic properties closely associated with macroscopic polarizations of ferroelectricity, including a prolonged polaron formation time (≈1.1 ps), a Stark splitting of the bleaching (≈63 meV), and a giant polaron Mott density (≈7.6 × 1018 cm−3). These findings broaden the realm of 2D polaron systems and reveal the decisive role of static/unidirectional polarizations on polaron physics in 2D LHPs.

Amentoflavone (AME) is a flavonoid compound found in over 120 plants. Its extensive pharmacological activity for treating cardiocerebrovascular diseases and neurological disorders have attracted the attention of researchers in recent years. However, owing to the poor solubility and low bioavailability of AME, it has not been developed as a drug for treating these diseases. This review focuses on two aspects of AME: First, it provides a detailed summary and introduction to AME based on its chemical structure, physicochemical properties, plant sources, extraction and purification methods, administration systems, and pharmacokinetic properties. Second, it summarizes the effects of AME on cardiocerebrovascular diseases and neurological disorders, and its specific pharmacological mechanisms. This review aims to promote the use of AME for treating cardiocerebrovascular diseases and neurological disorders. AME exhibits multiple activities, indicating its potential as a natural drug for treating these diseases. Further studies on its pharmacokinetics and toxicology are required to ensure its safety and efficacy.

The safety and efficiency of lithium‐ion batteries (LIBs) suggest a promising future for this technology, particularly in the automobile industry. However, thermal runaway—wherein a LIB undergoes an uncontrollable increase in temperature that may result in smoke, fire, or explosion—represents an important and widely studied failure type. Since the electrodes of LIBs are manufactured from porous composite materials, their heterogeneity can significantly influence the effective material characteristics and microscale behaviors of LIBs during operation. Microstructure geometric and electrochemical–thermal models are typically used to investigate these impacts. Herein, a microstructure geometric model is constructed of LIB's electrodes. A virtual multiphysics model is used to simulate the overcharging thermal runaway condition. The model's accuracy is validated through real‐world experiments. The model shows greater accuracy compared to the result from a conventional homogeneous geometric model and better reflects the heterogeneous internal phenomenon. The model is applied to a variable analysis in order to investigate how the varying heterogeneity of the cathode's porosity impacts the cell during overcharging thermal runaway behavior. Our results indicate that decreasing porosity heterogeneity at the cathode may delay thermal runaway, owing to the heterogeneous impact on particle diffusion behaviors and the side reaction rate.

Sequestration of CO2 in the unmineable coal seams is not only one of the most ideal options for reducing greenhouse gas effects, but also the only way for the coal industry to reduce CO2 emissions and achieve low carbonization sustainable development. However, the key unresolved issues regarding the CO2 geo-sequestration in coal seams is: “how long does CO2 injected into a coal seam remain in the seam?”. In this regard, on the basis of clarifying the hysteresis law of CO2 desorption in coals, this paper reveals the mechanism of supercritical CO2 desorption hysteresis, establishes a quantitative model for the geological storage of CO2, and explores the use of desorption hysteresis to achieve a long-term safe storage of CO2 in coal seams. The study results shows that the degree of desorption hysteresis of supercritical CO2 in coal is greater than that of subcritical CO2, and a stable hysteresis characteristic similar to a “parallel line” in the supercritical phase is formed between the adsorption and desorption isotherm. The fundamental reason for the desorption hysteresis is that the micro and nano sized pores in coal form curved surfaces due to their hydrophilicity, which generate strong capillary pressure following the Laplace’s equation, absorb liquid water, truncate and fix the supercritical CO2 fluid, and ultimately form CO2 residual trapping. For example, the cylindrical inorganic pores with a diameter of 40–10 nm in coal can generate a capillary pressure of 7.30–29.12 MPa, which is sufficient to block supercritical CO2. Taking the desorption isotherm of Jiulishan coal as an example, using the quantitative model for the geological storage of CO2 established in this study, it has been estimated that the total trapping capacity of the No.21 coal seam at depths of 900–1 500 m is stable at 35–37 m3/t. Among them, the adsorption trapping capacity accounts for about 80%, residual trapping capacity accounts for about 15%, and structural trapping capacity only accounts for 5%. Desorption hysteresis suggests that some measures should be taken to increase the proportion of CO2 residual trapping in coal seams as much as possible, the reason is that the residual CO2 sealed by capillary blockage is safer and has no risk of leakage compared to the free and adsorbed CO2 sealed by surrounding rock. The physical parameters such as ash content, moisture content, pore size, and morphology of coal seams are the main factors affecting the residual trapping efficiency.

Abstract The magnetic pulse welding method using a uniform pressure electromagnetic actuator can effectively weld dissimilar metal plates. However, the existing uniform pressure welding method leads to serious thinning of the plate at the chamfer, lack of welding at the center, and bulging of the welded sample, which seriously affects the quality of the welded joint. To solve these problems and improve the quality of welded joints, a new uniform pressure welding method of dissimilar metal plates based on pre-deformation was developed in this work. In this study, using the welding of an AA1060 aluminum plate and an SS304 steel plate with a thickness of 1 mm as an example, it was confirmed through numerical simulation and experimental research that the pre-deformation of the flyer plate controlled the impact angle of the central area of the plate, and it effectively suppressed central non-welding and serious bulge issues. Further, the welding method also reduced the height of the cushion blocks on both sides, thus mitigating aluminum plate thinning at the chamfer, ultimately improving the tensile strength of the joint. Additionally, a microscopic observation showed that the welding interface formed a wavy composite interface, and the connection strength was good. This welding method can also be extended to welding other dissimilar metal plates.

Abstract Metasurfaces are capable of fully reshaping the wavefronts of incident beams in desired manners. However, the requirement for external light excitation and the resonant nature of their meta-atoms, make challenging their on-chip integration. Here, we introduce the concept and design of a fresh class of metasurfaces, driven by unidirectional guided waves, capable of arbitrary wavefront control based on the unique dispersion properties of unidirectional guided waves rather than resonant meta-atoms. Upon experimentally demonstrating the feasibility of our designs in the microwave regime, we numerically validate the introduced principle through the design of several microwave meta-devices using metal-air-gyromagnetic unidirectional surface magneto-plasmons, agilely converting unidirectional guided modes into the wavefronts of 3D Bessel beams, focused waves, and controllable vortex beams. We, further, numerically demonstrate sub-diffraction focusing, which is beyond the capability of conventional metasurfaces. Our unfamiliar yet practical designs may enable full, broadband manipulation of electromagnetic waves on deep subwavelength scales.

Abstract The timely detection and management of hemorrhagic shock hold paramount importance in clinical practice. This study was designed to establish a nomogram that may facilitate early identification of hemorrhagic shock in pediatric patients with multiple-trauma. A retrospective study was conducted utilizing a cohort comprising 325 pediatric patients diagnosed with multiple-trauma, who received treatment at the Children's Hospital, Zhejiang University School of Medicine, Zhejiang, China. For external validation, an additional cohort of 144 patients from a children's hospital in Taizhou was included. The model's predictor selection was optimized through the application of the Least Absolute Shrinkage and Selection Operator (LASSO) regression. Subsequently, a prediction nomogram was constructed using multivariable logistic regression analysis. The performance and clinical utility of the developed model were comprehensively assessed utilizing various statistical metrics, including Harrell's Concordance Index (C-index), receiver operating characteristic (ROC) curve analysis, calibration curve analysis, and decision curve analysis (DCA). Multivariate logistic regression analysis identified systolic blood pressure (ΔSBP), platelet count, activated partial thromboplastin time (APTT), and injury severity score (ISS) as independent predictors for hemorrhagic shock. The nomogram constructed using these predictors demonstrated robust predictive capabilities, as evidenced by an impressive area under the curve (AUC) value of 0.963. The model's goodness-of-fit was assessed using the Hosmer–Lemeshow test (χ2 = 10.023, P = 0.209). Furthermore, decision curve analysis revealed significantly improved net benefits with the model. External validation further confirmed the reliability of the proposed predictive nomogram. This study successfully developed a nomogram for predicting the occurrence of hemorrhagic shock in pediatric patients with multiple trauma. This nomogram may serve as an accurate and effective tool for timely and efficient management of children with multiple trauma.

Abstract The development of Type I photosensitizers (PSs) is of great importance due to the inherent hypoxic intolerance of photodynamic therapy (PDT) in the hypoxic microenvironment. Compared to Type II PSs, Type I PSs are less reported due to the absence of a general molecular design strategy. Herein, we report that the combination of typical Type II PS and natural substrate carvacrol (CA) can significantly facilitate the Type I pathway to efficiently generate superoxide radical (O2 –•). Detailed mechanism study suggests that CA is activated into thymoquinone (TQ) by local singlet oxygen generated from the PS upon light irradiation. With TQ as an efficient electron transfer mediator, it promotes the conversion of O2 to O2 –• by PS via electron transfer-based Type I pathway. Notably, three classical Type II PSs are employed to demonstrate the universality of the proposed approach. The Type I PDT against S. aureus has been demonstrated under hypoxic conditions in vitro. Furthermore, this coupled photodynamic agent exhibits significant bactericidal activity with an antibacterial rate of 99.6% for the bacterial-infection female mice in the in vivo experiments. Here, we show a simple, effective, and universal method to endow traditional Type II PSs with hypoxic tolerance.

The strength and plasticity of 10B38 boron containing cold heading steel under different high temperature condi⁃ tions were studied using high-temperature tensile testing method. The results showed that the tensile strength decreased significantly from 124. 8 MPa to 22. 9 MPa at temperatures ranging from 700 to 950 ℃； At 950 to 1 150 ℃， the tensile strength was 12. 7 to 25. 5 MPa. In terms of thermoplastic properties， the cross-sectional shrinkage rate at 700-750 ℃ was 56%-72%； When the temperature was between 800 and 1 050 ℃， the cross-sectional shrinkage rate was ≥ 75%； When the temperature was between 1 050 and 1 150 ℃， the cross-sectional shrinkage rate was greater than 65%. Based on the above experimental data， the strength of the secondary cooling water in continuous casting was optimized from a specific water content of 1. 35 L/kg to a specific water content of 1. 25 L/kg. After optimization， the crack index of the continuous casting slab was significantly reduced. The dynamic CCT curves of 10B38 boron containing cold heading steel were mea⁃ sured， The experimental results showed that when the cooling rate was 0. 2-1 ℃/s， the test steel was mainly composed of softer ferrite structure； When the cooling rate was 3-10 ℃/s， the experimental steel was mainly composed of pearlite struc⁃ ture； When the cooling rate was 20 ℃/s and 30 ℃/s， the structure of the test steel was flat noodles martensite+pearlite； When the cooling rate was 50 ℃/s， a complete martensitic structure was formed at room temperature. The experimental re⁃ sults showed that by reducing the cooling rate to 0. 5-2 ℃/s， ideal ferrite and pearlite hot-rolled structures can be obtained.

Abstract During cell differentiation, growth, and development, cells can respond to extracellular stimuli through communication channels. Pannexin (Panx) family and connexin (Cx) family are two important types of channel-forming proteins. Panx family contains three members (Panx1-3) and is expressed widely in bone, cartilage and muscle. Although there is no sequence homology between Panx family and Cx family, they exhibit similar configurations and functions. Similar to Cxs, the key roles of Panxs in the maintenance of physiological functions of the musculoskeletal system and disease progression were gradually revealed later. Here, we seek to elucidate the structure of Panxs and their roles in regulating processes such as osteogenesis, chondrogenesis, and muscle growth. We also focus on the comparison between Cx and Panx. As a new key target, Panxs expression imbalance and dysfunction in muscle and the therapeutic potentials of Panxs in joint diseases are also discussed.

Abstract This study combines laboratory experiments and discrete element simulation methods to analyze the mechanism and deterioration patterns of sandstone surrounding rock voiding the bottom of a heavy-haul railway tunnel. It is based on previously acquired measurement data from optical fiber grating sensors installed in the Taihangshan Mountain Tunnel of the Wari Railway. By incorporating rock particle wastage rate results, a method for calculating the peak strength and elastic modulus attenuation of surrounding rock is proposed. Research indicates that the operation of heavy-haul trains leads to an instantaneous increase in the dynamic water pressure on the bottom rock ranging 144.4–390.0%, resulting in high-speed water flow eroding the rock. After 1–2 years of operation, the bottom water and soil pressures increase by 526.5% and 390.0%, respectively. Focusing on sandstone surrounding rock with high observability, laboratory experiments were conducted to monitor the degradation stages of infiltration, particle loss, and voiding of rock under the action of dynamic water flow. The impact of water flow on the “cone-shaped” bottom rock deformation was also clarified. The extent of rock deterioration and voiding was determined using miniature water and soil pressure sensors in conjunction with discrete element numerical simulations. The measured rock particle loss was used as a criterion. Finally, a fitting approach is derived to calculate the peak strength and elastic modulus attenuation of surrounding rock, gaining insight into and providing a reference for the maintenance and disposal measures for the bottom operation of heavy-haul railway tunnels.

To comprehensively investigate the evolution of the stress field, a three-dimensional thermodynamic model of laser cladding was developed in this paper. By analyzing the physical process and constructing a mathematical model, the temperature transfer and stress distribution were calculated. The simulation examined the evolution and distribution of stress at various scanning speeds, discussing the interplay between the temperature field and the stress field during rapid heating and cooling. Residual stress was measured through X-ray diffraction in experiments, and the crack distribution within the cladding layer was observed. The findings indicated that the stress values calculated from the simulation model aligned well with the experimental results. By combining experimental data, we conducted a qualitative analysis of the distribution of residual stresses and the trends of crack initiation, leading to the proposal of an optimized processing scheme that significantly enhances the quality and reliability of the cladding layer.