Damage Process Research Articles

Investigating DNA damage caused by COVID-19 and influenza in post COVID-19.

The SARS-CoV-2 virus (termed COVID-19) was responsible for over 34 million global deaths. Although the COVID-19 pandemic has subsided, infection by emerging mutant variants of SARS-CoV-2 poses a continuing threat to public health. COVID-19 infection has been associated with the development of cytokine storm syndrome, hypercoagulability, immunological dysregulation and direct viral invasion of organs, and the long-term consequences for the health of COVID-19 survivors are currently unknown. Our research focuses on the possible mutagenic aspects of infection by COVID-19 and measures their harmful effects on DNA composition. DNA damage was investigated, using the comet assay method, during two periods: in the epidemic peak of COVID-19 and during the post-COVID-19 period, both in patients infected with COVID-19 and in those with influenza. During the epidemic peak, the levels of DNA damage ranged from the highest to the lowest levels in the following groups, respectively: intubated-ICU, non-intubated-ICU, non-ICU, and influenza, with a discernible increase in DNA damage in ICU-treated patients. The levels of DNA damage in the post-COVID-19 period were significantly lower compared to those in the epidemic peak period but there was still a discernible increase in DNA damage in the ICU group. Our results indicate that levels of DNA damage may be an effective indicator in prognostic decision-making and may therefore help to reduce mortality. Given that DNA damage and impaired repair processes can contribute to chronic diseases like diabetes, cancer, and neurodegenerative conditions, it will be crucial to investigate potential similar effects in patients with COVID-19.

THE ROLE OF INTRACELLULAR SIGNALING PATHWAYS IN THE DEVELOPMENT OF TROPHIC PATHOLOGIES OF THE LOWER EXTREMITIES AND THEIR REGENERATION UNDER TYPE 2 DIABETES (PART 1)

Introduction. This review article addresses the critical issue of the development and regeneration of chronic trophic ulcers in the context of type 2 diabetes. This pathological process is associated with inhibited cell proliferation, impaired differentiation of various cell types, and disrupted mechanisms that regulate cell death. An analysis of recent scientific literature also highlights the involvement of key intracellular signaling pathways in the development of chronic ulcerative pathologies of the lower extremities, as observed in both experimental animal models and patients with type II diabetes. Despite advancements, this issue remains insufficiently explored in both theory and practice, underscoring its ongoing relevance. The aim of this study is to identify the roles of key signaling pathways—transforming growth factor β (TGF-β), phosphatidylinositol 3-kinase/serine-threonine kinase (PI3K/Akt), and Wnt/β-catenin—in the inflammatory response, regenerative mechanisms, and healing processes of soft tissue damage and trophic ulcers in experimental animals and patients with type II diabetes. Materials and Methods. This study is based on an analysis of current scientific literature that addresses this topic. Results. It has been found out that changes in the content and activity of key molecules of signaling pathways lead to disruption of carbohydrate homeostasis and the occurrence of structural and functional dysfunction in damaged tissues against the background of type II diabetes. These include TGF-β, PI3K, Akt and β-catenin. Analysis of experimental data demonstrated that both under the conditions of type II diabetes development and in the occurrence of chronic ulcers of the lower extremities, against the background of this endocrine disease, there is an increase in the level of TGF-β. At the same time the activity of the PI3K/Akt signaling pathway in the above-mentioned studied groups was reduced. The relationship between the development of type II diabetes and the Wnt/β-catenin signaling pathway has been established. Suppression of its activity was accompanied by impaired regeneration of chronic trophic ulcers in type II diabetes. Conclusion. Thus, the mechanism of type II diabetes and chronic peptic ulcer disease, in the same pathology, is associated with a impaired activity of signaling cascades. This concerns the following cellular systems such as TGF-β, PI3K/Akt and Wnt/β-catenin. They can be considered as potential therapeutic targets for the development of newest methods for the treatment of chronic trophic ulcers in type II diabetes in order to accelerate the recovery process of volumetric tissue damage of the lower extremities.

Strain‐Controlled Low‐Cycle Fatigue Behavior of a Superalloy Considering Extensive Temperature Range and Stress Concentration

ABSTRACTThis study aims to investigate the low cycle fatigue (LCF) behavior and fatigue life prediction method of an advanced solid solution–strengthened nickel‐based superalloy at various temperatures and stress concentrations. Cylindrical specimens as well as plates with three types of holes (including straight holes and inclined holes with different orientations) were designed and machined for fatigue tests. The test results revealed fatigue life decreases with the temperature increasing. Meanwhile, the fatigue lives of the plate specimens have decreased differently and are strongly dependent on the geometry and orientation of the holes. The key damage parameter related to the fatigue life was found on the strain gradient path. A criterion based on strain gradient is defined as the boundary of the damage process zone. The results show that the prediction was in good agreement with the experimental data, for the majority of the data are within a scatter band of ±2.

Impact of Peritoneal Neutrophil Extracellular Traps on Peritoneal Characteristics and Technical Failure in Patients Undergoing Peritoneal Dialysis.

Peritoneal dialysis (PD) is an effective home therapy for end-stage kidney disease. However, continuous exposure to PD fluids with high glucose concentration and recurrent peritonitis may lead to the activation of cellular and molecular processes of peritoneal damage, including inflammation and fibrosis. In particular, recent studies have highlighted the role of neutrophils in chronic inflammation. This study explores how neutrophil extracellular traps (NETs) affect peritoneal membrane function and contribute to technical failures in PD patients. We conducted a prospective observational study involving 250 non-infectious and 30 acute peritonitis patients. NETs were measured using nucleosome and myeloperoxidase DNA levels in PD fluids. Monocyte chemoattractant protein-1 (MCP-1) and matrix metalloproteinase-8 (MMP-8) were also measured to assess peritoneal inflammation and damage. A significant increase in peritoneal NETs, as determined by nucleosome and myeloperoxidase DNA levels, was observed in patients with acute peritonitis compared to patients without peritonitis. Even in non-infectious samples, NET levels were widely distributed and closely correlated with levels of MCP-1 and MMP-8. Higher levels of peritoneal NETs were closely associated with increased 4-hour dialysate/peritoneal (D/P) creatinine ratio and 1-hour D/P sodium levels, indicating a higher prevalence of fast transport and limited free water transport. These factors were associated with a higher risk of technical failure. During a mean follow-up of 34 months, 39.2% (98 patients) switched from PD to hemodialysis, with higher NET levels significantly increasing the risk by 1.9 times (95% confidence interval 1.27-2.83, p=0.020). This study suggests the importance of peritoneal NETs not only as markers of acute inflammation but also as significant immunological predictors of chronic peritoneal membrane inflammation and dysfunction, and as potential risk factors for technical failure.

Triptolide induces hepatotoxicity by promoting ferroptosis through Nrf2 degradation

BackgroundTriptolide (TP), a principal active substance from Tripterygium wilfordii, exhibits various pharmacological effects. However, its potential hepatotoxicity has always been a significant concern in clinical applications.PurposeThis research aimed to explore the involvement of ferroptosis in TP-mediated hepatic injury and the underlying mechanisms.MethodsIn this study, in vitro and in vivo experiments were involved. Hepatocyte damage caused by TP was evaluated using MTT assays, liver enzyme measurement and H&E staining technique. Ferroptosis was assessed by measuring iron level, lipid peroxide, glutathione (GSH), mitochondrial morphology and the key protein/mRNA expression implicated in ferroptosis. To verify the contribution of ferroptosis to TP-induced liver damage, the ferroptosis inhibitor Ferrostatin-1 (Fer-1) and a plasmid for overexpressing glutathione peroxidase 4 (GPX4) were employed. Subsequently, nuclear factor erythroid 2-related factor 2 (Nrf2) knockout mice and Nrf2 overexpression plasmid were utilized to investigate the underlying mechanisms. Nontargeted lipidomics was used to analyze lipid metabolism in mouse liver. Moreover, the cellular thermal shift assay (CETSA), cycloheximide (CHX) and MG132 treatments, and immunoprecipitation (IP) assays were applied to validate the binding of TP to Nrf2 and their interactions.ResultsTP triggered ferroptosis in hepatocytes, as indicated by iron accumulation and lipid peroxidation. Ferroptosis was responsible for TP-induced hepatic injury. During the process of TP-induced liver damage, the Nrf2 signaling pathway was significantly suppressed. Notably, the deletion of Nrf2 in mice aggravated the extent of liver injury and ferroptosis associated with TP, whereas enhancing Nrf2 expression in cells significantly reduced TP-induced ferroptosis. Additionally, dysregulation of lipid metabolism was associated with TP-induced liver injury. TP may directly bind to Nrf2 and enhance its degradation through the ubiquitin–proteasome pathway, thereby inhibiting or reducing Nrf2 expression.ConclusionIn summary, the suppression of Nrf2 by TP facilitated the occurrence of ferroptosis, resulting in liver damage.Graphical abstract

Study on the failure and acoustic emission characteristics of coal under graded cyclic loading and unloading stress paths

To study the influence of cyclic disturbance stress on the mechanical behavior of coal during mining, a gas containing coal fluid-solid coupling servo seepage experimental system was used to conduct experimental research on the acoustic emission (AE) characteristics of gas containing coal under two stress paths of graded cyclic loading and unloading. The AE characteristics of coal damage and failure processes under different cyclic stress paths were analyzed. The research results indicate that: (1) The overall characteristics of AE signals for both graded cyclic loading and unloading paths are basically the same. With increasing of the amount of graded cyclic loading or unloading, the AE count reaches its maximum value when reaching failure, and the cumulative ringing calculation of AE increases exponentially. (2) The AE signals under the graded cyclic loading or unloading path exhibit obvious zoning characteristics. In the low and medium stress regions, the AE signal basically satisfies the Kaiser effect, while reaching the high stress region before failure, the AE signal exhibits a significant Felicity effect. (3) The concentration coefficient of AE and the intensity coefficient of the Kaiser effect have been newly defined. They are used to quantitatively characterize the extent of the Kaiser effect of AEs under graded cyclic stress. It was found that as the variation of graded cyclic stress increases, the concentration coefficient and Kaiser effect intensity coefficient both show a decreasing trend. (4) Combining the AF and RA values of AE, it was found that the coal failure signals of the two stress paths were basically similar, that is, the overall failure was mainly tensile failure, and the signals of cyclic unloading tensile failure were significantly more than those of cyclic loading. The AE signal characteristics studied in this article are of great significance for predicting coal power disasters.

Dual-Modality Accurate Visualization of Drug Synergy Based on Mass Spectrometry and Fluorescence Imaging.

There is a potential synergistic effect between nonsteroidal anti-inflammatory drugs and hydrogen sulfide (H2S), but direct evidence for the study is lacking. With a single fluorescence detection method, it is difficult to accurately confirm the effectiveness of the synergistic effect. In this study, the fluorescent probe and the nonsteroidal anti-inflammatory drug naproxen were combined via different self-immolative spacer groups to obtain a diagnostic and therapeutic integrated fluorescent probe Nap-NP-NSB, which can release H2S. The quantitative release of H2S by Nap-NP-NSB was evaluated in vitro and in cells, and the synergistic effect of H2S and naproxen was confirmed by monitoring the treatment process of cellular inflammation and oxidative damage of gastric mucosa cells. Finally, in vivo fluorescence imaging and mass spectrometry imaging of the liver and stomach tissues and their sections were performed in the mouse model of acute hepatitis. The dual-modal detection method not only confirmed that Nap-NP-NSB had better anti-inflammatory activity and less gastric mucosal damage, but also enabled a more accurate visualization of the drug synergistic effect of naproxen and H2S. This work provides a dual visualization imaging method combining fluorescence and mass spectrometry imaging and develops a new idea for studying drug synergies based on self-immolative structures.

Thermal stress in externally irradiated tubes of solar central receivers with a gas–particle fluidized dense suspension

One of the objectives of the new generation of concentrating solar power plants is to increase the actual temperature limit (565 °C) up to or near 1000 °C. An alternative heat transfer fluid that could help to reach this objective is the use of a fluidized dense gas–particle suspension ascending through a vertical tube. Since the predominant cause of rupture in solar receivers is the creep-fatigue damage process, which is mostly influenced by the maximum temperatures and stress experienced along the tube, the main objective of this work is to numerically study the thermomechanical behavior of a non-uniform externally irradiated tube where particles are fluidized and moves upwards. The heat transfer problem in the two media present (i.e. dense suspension of particles and tube wall) was solved separately: a Computational Particles Fluid Dynamic model solves the heat transfer in the particles, whereas a three dimensional Finite Volume model simulates the heat conduction through the tube wall to obtain the temperature profile, which serves as input to calculate the thermal stress of the tube with an analytical method. Higher thermal stresses were obtained for an absorbed power of 250 kW/m2 (σVM,max=219MPa) compared to that for an absorbed power of 500 kW/m2 (σVM,max=72MPa) due to the lower temperature difference between the front and rear sides of the tube caused by the more pronounced increase of the radiative losses in the front side of the tube compared to that at the rear side. The thermomechanical behavior of a particle receiver was compared to that of a molten salt receiver. For an incident solar flux of 500 kW/m2, the particle receiver reduced the maximum thermal stress by 73% compared to the molten salt receiver. However, the tube’s maximum temperature exceeded the working limit for stainless steel tubes. In order for the receiver to survive heat fluxes characteristic of solar power plants, research into technological solutions that allow to improve the effectiveness of the heat transfer rate from the tube to the particle flow is necessary.

Relation Between Striations Spacing and Fatigue Crack Growth Rates for Additive Manufactured Inconel 625

ABSTRACTThe principles of the mechanisms for fatigue crack propagation in metals have been established several decades ago. By definition, fatigue might be summarized as a damage process imparted to a material under the action of cyclic loads. The relation between fatigue crack growth rates (FCGRs) and formation of striation marks has been a controversial topic. Some authors stated that, in certain fatigue regimes, several fatigue cycles are required to form a single striation. The disagreement found was the motivation for the present work. This study's main goal is to provide a comparison between the striation spacing and the respective FCGR. These analyses will be performed in a Nickel superalloy, Inconel 625, obtained via directed energy deposition. Investigation of the striations spacing are compared with data obtained from FCGR tests. A good agreement between striation spacing and FCGRs was found to intermediate and large values of stress intensity factor.

Analysis of microcracking processes in microconcrete under confined compression utilising synchrotron-based ultra-high speed X-ray phase contrast imaging

In the present study, microconcrete (MC) samples were exposed to dynamic quasi-oedometric compression (QOC) tests and visualised in-situ by the means of MHz synchrotron X-ray phase-contrast imaging in the ESRF synchrotron in order to analyse the damage mechanisms governing the mechanical behaviour of concrete under high-strain-rate confined compression. To do so, small cylindrical samples were placed in polymeric confinement cell and dynamically compressed along their axial direction using SHPB (Split-Hopkinson Pressure Bar) set-up available in ID19 beamline in the European Synchrotron Radiation Facility (ESRF). The damage process was visualized with MHz X-ray phase-contrast imaging along with an ultra-high-speed camera operating at a recording frequency approximately 1 Mfps (million frames per second i.e., 880 ns interframe time). The axial stress and strain temporal profiles were obtained from standard Kolsky's (SHPB) data processing. In addition, data of radial stress and strain within the sample were deduced from non-linear analysis of the mechanical behaviour of the polycarbonate confining cell instrumented with a strain gauge. Finally, the onset and growth of microcracking observed from the equatorial zone of large spherical pores is correlated with deviatoric and pressure measurements showing how the pore collapse process develops during the applied mechanical loading.

Investigation into the effect of impact damage on compression behavior of the omega-stiffened composite panels

Abstract With superior performance and weight-saving potential, composite structures have been increasingly applied in the aerospace industry. The damage process and post-buckling deformation of composite panels under compressive load have been proven to limit the application of composite structures. For the purpose of utilizing the full potentiality of thin-walled composite structures, an experimental investigation was employed to explore the influence of impact damage on the buckling behavior and the load-carrying capacity of omega-stiffened composite panels. Pristine panels and impact-damaged panels were under compressive load until failure. The results showed that the pristine panels had higher compressive stability and ultimate strength, and the existence of impact damage led to a decline in the buckling load and the carrying capacity, which were up to 16% and 27%, respectively. Additionally, the complex stress state caused by the introduced impact damage influenced the buckling response and the damage patterns of the omega-stiffened panels. The pristine panels exhibited typical compression failure mode, with matrix crack and fiber breakage in the stringer and the skin. However, the collapse of the pre-damaged panels was dominated by the debonding of the skin-stiffener interface and the out-of-plane deformation of the skin.

Molecular dynamics simulation of particle radiation damage processes in ZnO crystals

Abstract The cascade collision process in ZnO crystal caused by Primary Knocked Atom (PKA) under different incident conditions has been simulated by the Molecular Dynamics (MD) method. Simulation results show that the incident depth is smaller than 20 atomic layers for PKAs with initial kinetic energy less than 2 keV, and more than 30 atomic layers for PKAs with energy larger than 5 keV. For PKAs with lower energy, the defects are mainly distributed near the incident trajectory, and the distribution range of defects becomes wider with the increase of PKA energy. When the PKA energy is less than 10 keV, the number of defects will reach the peak within 1 ps, and then the system enters into the annihilation process and reaches to steady state within 20 ps. In addition to the incident energy, the incident direction of PKA also has a great influence on the cascade collision process and defect distribution. Compared with two other cases, <111> direction and <001> direction, PKAs along <011> direction produces significantly more defects, with a distribution more concentrated, and the defect recombination rate is also higher in the annihilation process. The evolution of different types of defects in the cascade collision process is different, and the number of O vacancies is the largest, followed by the number of O interstitial atoms, Zn interstitial atoms, and Zn vacancies. Some of the interstitial O atoms replace the Zn vacancies during the annihilation process.

Rheological properties and excellent thermal shock stability of Al2O3-SiC-C castables containing continuous TiC coated graphite

High-flux molten iron and intermittent circulation accelerated the damage process of Al2O3-SiC-C castables under alternating thermal stress. A continuous TiC coated graphite was prepared using sol-gel combined with carbothermal reduction to investigate its influence on the flow properties, microstructure, mechanical properties and thermal shock resistance of Al2O3-SiC-C castables. The results show that a lower Ti/C molar ratio and higher heat treatment temperature are more favorable for the synthesis of TiC and the formation of a continuous and complete TiC coated graphite layer on the graphite surface. The introduction of TiC coated graphite significantly enhance the mechanical properties and thermal shock stability of Al2O3-SiC-C castables, with a remarkable 227% increase in residual strength after thermal shock. In addition, during the oxidation process of the samples with TiC coated graphite, TiO2 generated from the oxidation of TiC fills the pores and facilitates the growth of Al6Si2O13, which enhances the tightness of the bonding of the castable matrix, thus contributing to the improvement of the overall performance.

Investigations on the fracture mechanisms of Z-shaped fissured rock-like specimens

Complex shapes of cracks exist in natural rock masses, however, present research has simplified it into straight line-shaped fissures. In view of this, three-dimensional (3D) printing is employed to make Z-shaped fissured specimens with different main fissure angle α and secondary fissure angle β. The compress fracture experiments are conducted, and full-field strain distributions during crack propagations are obtained using Digital Image Correlation (DIC) technology. Traditional Smoothed Particle Hydrodynamics (SPH) method is improved to examine damage process as well as fracture mechanisms in Z-shaped fissured specimens. It can be concluded that: Wing Crack (WC), Main Crack (MC), Outer Crack (OC) and Inner Crack (IC) are observed in the experiment. The secondary fissure angle β guides the initiation of MC, while the main fissure angle α guides the initiation of WC. Stress–strain curve of 3D printing samples with Z-shaped fissures shows similar trends to that of real rock, experiencing four typical parts. Numerical results show high similarities with experimental results. We have also discussed the crack initiation mechanisms in various main fissure angle α and secondary fissure angle β in the end, and concluded the stress distribution characters. The findings of this research will offer some references for correct understanding of the crack evolution processes and fracture mechanics of Z-shaped fissured rock masses.

Study on the Process of Soil Clod Removal and Potato Damage in the Front Harvesting Device of Potato Combine Harvester

To improve soil clod removal and reduce potato damage in potato combine harvesters, this study investigates the processes involved in soil clod removal and potato collisions within the bar-lift chain separation device of the harvester. It outlines the structure and working principles of the machine, theoretically analyzes the key dimensions of the digging device and potato–soil separation components, and derives specific structural parameters. A dynamic mathematical model of the bar-lift chain is established, from which the dynamic equations are formulated. The analysis identifies factors that influence the dynamic characteristics of the bar-lift chain. This study examines the working principles and separation performance of the potato–soil separation device, with a focus on the collision characteristics between potatoes and both the screen surface and the bars. Key factors such as the separation screen’s line speed, the harvester’s forward speed, and the tilt angle of the separation screen are considered. Simulations are performed using a coupling method based on the Discrete Element Method (DEM) and Multi-Body Dynamics (MBD). Through simulation experiments, the optimal parameter combinations for the potato–soil separation device are determined. The optimal working parameters are identified as a separation screen line speed of 1.25 m/s, a forward speed of 0.83 m/s, and a tilt angle of 25°. Field harvesting experiments indicate a potato loss rate of 1.8%, a damage rate of 1.2%, an impurity rate of 1.9%, a skin breakage rate of 2.1%, and a yield of 0.15–0.21 ha/h. All results meet national and industry standards. The findings of this research provide valuable theoretical references for simulating potato–soil separation in combine harvesters and optimizing the parameters of these devices. Future potential research will consider the automatic regulation of the excavation volume of the potato–soil mixture, aiming to achieve intelligent control of the potato–soil separation operation.

Experimental investigation of seismic performance of precast concrete shear walls with overlapping U-bar loop connections

This paper discusses the seismic performance of five reduced-scale shear walls, including one cast-in-place (CIP) concrete shear wall, two precast concrete (PC) shear walls with overlapping U-bar loop connections, and two PC shear walls with modified form-overlapping U-bar loop connections combined with extruded sleeve connections. A quasi-static test was conducted to evaluate the reliability of the overlapping U-bar loop connections and the modified form by comparing the corresponding mechanical parameters of PC specimens with those of the CIP specimen. Moreover, the differences in seismic performance between the CIP specimen and PC specimens with different connection methods were also analyzed in terms of damage process, hysteretic loops and skeleton curves, load carrying capacity, ductility, equivalent stiffness, and energy dissipation. The experimental findings indicated that the mechanical performances of PC specimens with the modified connection form outperformed those of PC specimens with pure overlapping U-bar loop connections, closely resembling the properties of cast-in-place specimens; the failure mode of PC specimens was consistent with that of the CIP specimen; the generation, distribution and development of cracks in PC specimens were also similar to those in the CIP specimen. Furthermore, although the load-bearing capacity and peak displacement of PC specimens were lower than those of the CIP specimen due to the failure of the post-casted concrete strength to meet the requirements, the ductility, equivalent stiffness, and energy dissipation of PC specimens with the modified connection form closely matched that of the CIP specimen.

031. Urine Neutrophil Gelatinase-Associated Lipocalin (NGAL) Levels as a Predictor of Early Acute Kidney Injury in Post Coronary Artery Bypass Graft (CABG) Patients in H. Adam Malik Hospital Medan

Background: One of the main complications after open heart surgery is acute kidney injury. Coronary Artery Bypass Graft surgery is one of the main factors in this complication. Currently, the use of serum creatinine as one of the diagnostic criteria for AKI is not sensitive for diagnosing AKI at an early stage. Elevated urine NGAL levels are more indicative of a renal damage process than an increase in circulation. An increase in NGAL levels in urine can occur 100 times faster than circulating NGAL. Thus our research aimed to view NGAL ability to predict AKI in CABG patient. Methods: This research is an observational study with cross-sectional data collection methods to find out whether NGAL can be a predictor of AKI in patients who have undergone CABG surgery. Results: The collection of research subjects was stopped when the number of samples had been reached so that this study was a cohort study with consecutive sampling techniques. In the results of this study, we obtained 31 research samples. In 31 research samples, it was found that the average age was 61.46 years with a standard deviation of 8.2 years. This study was dominated by male gender with a total of 20 people or 64% of the total sample. After CABG surgery, it was found that 4 patients had postoperative acute renal failure or 13.3% of the total sample. The sensitivity of the instrument is 100% with a specificity of 96%. The accuracy of the NGAL is 97.5%. Conclusion: NGAL is a useful parameter to predict AKI and would have significant advantage however further study with multi-center design would be necessary to validate these result.

Battery Housing for Electric Vehicles, a Durability Assessment Review

Recent research emphasizes the growing use of advanced composite materials in modern transportation, highlighting their superior weight-to-strength ratio. These materials are increasingly replacing steel and aluminium in housings to enhance sustainability, improve efficiency, and reduce emissions. Considering these advancements, this article reviews recent studies on composite materials, focusing on fatigue life assessment models. These models, which include performance degradation, progressive damage, and S–N curve models, are essential for ensuring the reliability of composite materials. It is noted that the fatigue damage process in composite materials is complex, as failure can occur in the matrix, reinforcement, or transitions such as interlaminar and intralaminar delamination. Additionally, the article critically examines the integration of artificial intelligence techniques for predicting the fatigue life of composite materials, offering a comprehensive analysis of methods used to indicate the mechanical properties of battery shell composites. Incorporating neural networks into fatigue life analysis significantly enhances prediction reliability. However, the model’s accuracy depends heavily on the comprehensive data it includes, including material properties, loading conditions, and manufacturing processes, which help to reduce variability and ensure the precision of the predictions. This research underscores the importance of continued advancements and their significant scientific contributions to transportation sustainability, especially in the context of emerging artificial intelligence technologies.

Experimental study on modeling of shallow soil landslide reinforced by micropiles

The practical application of micropiles in landslide reinforcement and prevention advanced before theoretical research, significantly limiting their application and promotion. To determine the damage patterns and stress distribution of micropiles during sliding failure in reinforced shallow landslides, three sets of physical modeling tests were performed. These tests examined the stability of shallow soil slopes with and without micropiles, including single-row and three-row configurations. During the tests, the foot displacement of the landslide, the top displacement of the micropiles, and the strain within the micropiles were monitored throughout the loading process. Following the tests, the landslide was excavated to observe the damage patterns in the micropiles. The experimental results showed that the pile-soil composite structure formed by three rows of micropiles, together with the soil between them, significantly improved the stability of the landslide and demonstrated effective anti-sliding effects. The stress distribution curve of the micropile was inversely S-shaped, with the peak stress located near the sliding surface. Within the micropile group, the first row exhibited the highest stress, and the micropiles nearest to the free face experienced the greatest displacement. Through the micropile-reinforced landslide tests, we identified three stages in the slope’s sliding damage process and the stress distribution pattern of the micropiles. The research findings offer valuable insights into the anti-sliding mechanism of micropiles, which can guide design and construction.

Intensify the hindrance to gas entrapment on the construction of Al 5356 thin-walled structure by tuning the WAAM process parameters

Abstract Compared to other metallic additive manufacturing methods, Wire Arc Additive Manufacturing (WAAM) has a number of advantages, such as less equipment capital required and more material composition flexibility. However, uneven welding and feed rates, as well as inadequate gas flow, can result in flaws such oxidation, gas entrapment, and humping. This study aims to reduce gas entrapment, maximize tensile strength, and reduced elastic modulus of the WAAM Al5356 wall by optimizing gas flow rate (13, 16 and 19 l min−1) in conjunction with welding and feed rates. The study highlighted gas flow rate as the most important component in pore formation and used the Entropy approach in conjunction with the COmplex PRoportional ASsessment (COPRAS) tool to identify ideal settings. The reduction in gas entrapment to 0.02%, as shown in the confirmation studies, resulted in a 33.9% rise in tensile strength and a 64.7% rise in elastic modulus. To verify these ideal parameters, elastic modulus mapping was done on the printed WAAM Al5356 wall. Moreover, the damage processes connected to gas entrapment and humping development were examined using fractography. Consequently, the research determined the ideal conditions to generate a multi-layer structure free of defects, improving its practicality in aerospace and automotive sectors.