The shear adhesive strength at the clay‒metal interfaces serves as a critical parameter for evaluating the soil adhesion and metal interface mudding phenomena.However,its rapid determination remains challenging becaus...The shear adhesive strength at the clay‒metal interfaces serves as a critical parameter for evaluating the soil adhesion and metal interface mudding phenomena.However,its rapid determination remains challenging because of the demanding requirements for high-precision instrumentation and complex calibration procedures.In this study,an integrated framework was presented that combined physical experiments,theoretical approaches,and machine learning to enable the autonomous determination of the shear adhesive strength of soil under multiple influencing factors.We developed an improved particle swarm optimization-optimized ordinary kriging(IPOK)surrogate testing method to enhance the limited experimental datasets,and a lightweight residual neural network(RLNet)was then used for effective intra-and extra-domain predictions.A comprehensive model discussion,comparison,and interpretability analysis were conducted.The results from 64 physical experiments considering the consistency index,normal stress,clay content,rotation rate,and disc material effectively characterized the shear adhesion behaviour of kaolin.The IPOK surrogate experiments successfully replicated the physical data points while enriching the dataset details.The RLNet model trained with IPOK data achieved superior prediction performance,with a root mean square error of 7.491 and a determination coefficient of 0.927 in 16 orthogonal validation tests,and high similarity was attained between the predicted and measured values.A detailed model discussion analysis confirmed the superiority of the IPOK-RLNet framework.This methodology provides a cost-effective rapid analysis technique for assessing clay‒metal interface shear adhesion,significantly reducing laboratory testing requirements and experimental costs while increasing engineering efficiency.展开更多
As a specific spoilage organism of seafood under refrigerated temperature conditions,Shewanella spp.tend to form biofilms that exacerbate the occurrence of seafood spoilage.Biofilm-promoting factor A(BpfA)has been rep...As a specific spoilage organism of seafood under refrigerated temperature conditions,Shewanella spp.tend to form biofilms that exacerbate the occurrence of seafood spoilage.Biofilm-promoting factor A(BpfA)has been reported to promote the adhesion and biofilm formation of Shewanella spp.,but its role in adhesion and biofilm formation of S.putrefaciens under cold stress needs to be further investigated.To better comprehend the effect of BpfA on adhesion and biofilm formation of S.putrefaciens under cold stress(4℃),bacterial adhesion and biofilm phenotype of S.putrefaciens CN32 WT andΔbpfA at 4℃were analyzed and performed transcriptomics.The results showed that the deletion of bpfA had almost no effect on the growth of S.putrefaciens CN32 at 4℃,but weakened the unicellular adhesion capacity of S.putrefaciens CN32 and destabilized the stability of the multicellular adhesion layer.In addition,the biomass of the mature biofilm formed byΔbpfA was merely around 50%of that observed in the mature biofilm of S.putrefaciens CN32 WT,the average thickness and volume of the biofilm decreased by 18%and 27%,respectively,and the composition of the biofilm changed.Transcriptome analysis demonstrated that the deletion of bpfA led to differential expression of genes involved in metabolic pathways such as bacterial chemotaxis,two-component system,tyrosine metabolism,drug metabolism-other enzymes and biofilm formation-Vibrio cholerae,which in turn influenced bacterial adhesion and biofilm formation.Those results advance our acknowledgment of the character of BpfA on adhesion and biofilm formation of S.putrefaciens CN32,which contributes to understanding bacterial adhesion and the control of biofilm formation.展开更多
Objective:To explore the effects of Punica granatum L.(P.granatum,Shi Liu)seed in the management of peritoneal adhesions(PAs)in rats.Methods:The mature male rats were separated into the following groups,each containin...Objective:To explore the effects of Punica granatum L.(P.granatum,Shi Liu)seed in the management of peritoneal adhesions(PAs)in rats.Methods:The mature male rats were separated into the following groups,each containing six animals:a sham group without peritoneal adhesion induction,a negative control group,and four intervention groups with both peritoneal adhesion induction and administration of 2 mL of vehicle or 0.1%,0.3%,1%,or 3%w/v P.granatum seed Soxhlet(PSS).Peritoneal adhesions were assessed through macroscopic examination,transforming growth factor-β1(TGF-β1),vascular endothelial growth factor(VEGF),and inflammatory cytokine tumor necrosis factor-α(TNF-α)levels were evaluated using biochemical methods.Results:The findings revealed no notable differences in adhesin scores between the therapeutic and negative control groups,but PSS(1 and 3%w/v)significantly reduced TNF-α,VEGF,and TGF-β1 levels compared with those in the negative control group(all P<.01).Conclusion:The results indicate that PSS is a potential treatment option for intraperitoneal adhesions.展开更多
In this paper,our main goal is to study a new mathematical model which describes the frictional contact between a foundation and a deformable body which is composed of viscoplastic materials and where the process is c...In this paper,our main goal is to study a new mathematical model which describes the frictional contact between a foundation and a deformable body which is composed of viscoplastic materials and where the process is considered dynamic.The contact condition on the normal plane is modeled by a unilateral constraint condition for a version of normal velocity in which the memory effect and the adhesion are considered.On the tangential plane a frictional contact condition is governed by the Clarke subdifferential of a locally Lipschitz function,and the evolution of the bonding field is governed by an ordinary differential equation.We formulate this problem as coupled system that consists of two ordinary differential equations and a variational-hemivariational inequality.Then,the existence,uniqueness and continuous dependence of the solution on the data results concerning the abstract system are established.Finally,we use the abstract results to show the existence and uniqueness of the solution to the contact problem.展开更多
The operational temperature rise of photovoltaic(PV)panels reduces their power generation efficiency and shortens their lifespan.Hygroscopic hydrogel-based evaporative cooling technology provides a promising solution ...The operational temperature rise of photovoltaic(PV)panels reduces their power generation efficiency and shortens their lifespan.Hygroscopic hydrogel-based evaporative cooling technology provides a promising solution for PV cooling due to high-enthalpy water evaporation.However,current hydrogels remain plagued by cooling interface mismatch and environmental concerns,which limit their practical implementation.Herein,a“green”and self-adhesive hygroscopic hydrogel consisting only of cheap lotus root powder and LiCl is designed,which can form robust interfacial adhesion with PV panels for efficient and durable cooling.Leveraging its compelling hygroscopicity,the hydrogel is able to rapidly capture moisture to recover cooling capacity,thus achieving self-sustained cooling.Besides,the“salting-in”effect brought by LiCl endows the hydrogel with notable softness and self-adhesiveness,which enables it to tightly combine with PV panels to optimize heat conduction and improve cooling efficiency.As a result,under 1.0 kW m^(-2)illumination,a PV temperature drop of 18.2℃ and a cooling power of 358 W m^(-2)were delivered by attaching the hydrogel to the rear of the PV panel,accompanied by a 7.7%improvement in energy efficiency.Overall,this self-sustained passive cooling strategy,activated by the all-natural hydrogel,sheds light on the development of PV thermal management.展开更多
Systematic understanding of the interaction between cells and their microenvironment is of wide interest.To investigate this interaction,a flexible micropillar array device integrating dual functions of cell behavior ...Systematic understanding of the interaction between cells and their microenvironment is of wide interest.To investigate this interaction,a flexible micropillar array device integrating dual functions of cell behavior regulation and adhesion measurement is developed.Micropillar arrays with high and low densities are designed to explore the role of substrate topography in the behavior of human bone marrow mesenchymal stem cells.In addition,a method is established for quantifying weak cell adhesion forces on the basis of micropillar deflections.The results show that cell cytoplasmic adhesion is greater on a low-density micropillar array than that on a high-density array and is localized mainly in the perinuclear region of the cytoplasm rather than in pseudopods.It is also found that the micropillar array topography facilitates the oriented spreading of cell morphology and pseudopod formation,and a reduction in focal adhesion aggregation and F-actin polarization compared with a flat substrate.Notably,cells cultured on a low-density micropillar array exhibited a higher number of pseudopods,stronger adhesion forces,and greater stiffness compared with those on a high-density array.In summary,this work employs an adhesion force sensor,immunofluorescence staining,and atomic force microscopy to investigate the mechanical properties of cells and elucidate the mechanisms by which micropillar topographical cues regulate the adhesion of mesenchymal stem cells to the substrate.The micropillar array force sensor developed in this study provides an effective tool for simultaneously modulating cell behavior and quantifying adhesion forces,offering valuable insights for biomechanical research.展开更多
Objective:Endometrial tuberculosis,which commonly affects women of reproductive age,is a significant cause of intrauterine adhesions(IUA),potentially leading to hypomenorrhea,amenorrhea,and infertility.Hysteroscopic a...Objective:Endometrial tuberculosis,which commonly affects women of reproductive age,is a significant cause of intrauterine adhesions(IUA),potentially leading to hypomenorrhea,amenorrhea,and infertility.Hysteroscopic adhesiolysis is the primary treatment for IUA;however,studies specifically addressing its efficacy in tuberculosisinduced IUA remain scarce.This study aims to evaluate the therapeutic outcomes of hysteroscopic adhesiolysis for IUA caused by endometrial tuberculosis.Methods:This retrospective cohort study included patients diagnosed with tuberculosisinduced IUA who underwent hysteroscopic adhesiolysis at the Third Xiangya Hospital of Central South University between May 2014 and October 2022.Clinical data including age,medical history,adhesion severity,surgical treatment,and reproductive outcomes were analyzed.Results:Among 39 patients identified,2 were lost to follow-up.A total of 37 patients were included,with a follow-up duration ranging from 6 months to 9 years.Hypomenorrhea was reported in 24(64.9%)patients,secondary amenorrhea in 10(27.0%)patients,and normal menstruation in 3(8.1%)patients.Most patients presented with primary infertility(59.5%),and only 2(5.4%)had secondary infertility.The median American Fertility Society(AFS)score at initial assessment was 10(range,8−12);8(21.6%)patients had moderate IUA,and 29(78.4%)had severe IUA.A total of 86 surgical procedures were performed across 37 patients,with 27 patients undergoing 2 or more surgeries.Postoperatively,25(67.6%)patients achieved normalization of the uterine cavity,while 12(32.4%)still had a reduced cavity.Only 7(18.9%)patients had a grossly normal endometrium at the final surgery,all of whom had moderate adhesions at the initial procedure.Menstrual flow returned to normal in 12(32.4%)patients,while 25(67.6%)continued to experience hypomenorrhea.Of 29 patients who attempted in vitro fertilization and embryo transfer(IVF-ET),only 6(20.7%)conceived.Among these,4(13.8%)delivered at term via cesarean section;one case was complicated by postpartum hemorrhage due to uterine atony and another by placental adhesion.Conclusion:Endometrial tuberculosis can lead to severe IUA.Hysteroscopic adhesiolysis facilitates cavity restoration and improvement of menstrual conditions,but the overall reproductive outcomes remain suboptimal.展开更多
Due to their high mechanical compliance and excellent biocompatibility,conductive hydrogels exhibit significant potential for applications in flexible electronics.However,as the demand for high sensitivity,superior me...Due to their high mechanical compliance and excellent biocompatibility,conductive hydrogels exhibit significant potential for applications in flexible electronics.However,as the demand for high sensitivity,superior mechanical properties,and strong adhesion performance continues to grow,many conventional fabrication methods remain complex and costly.Herein,we propose a simple and efficient strategy to construct an entangled network hydrogel through a liquid-metal-induced cross-linking reaction,hydrogel demonstrates outstanding properties,including exceptional stretchability(1643%),high tensile strength(366.54 kPa),toughness(350.2 kJ m^(−3)),and relatively low mechanical hysteresis.The hydrogel exhibits long-term stable reusable adhesion(104 kPa),enabling conformal and stable adhesion to human skin.This capability allows it to effectively capture high-quality epidermal electrophysiological signals with high signal-to-noise ratio(25.2 dB)and low impedance(310 ohms).Furthermore,by integrating advanced machine learning algorithms,achieving an attention classification accuracy of 91.38%,which will significantly impact fields like education,healthcare,and artificial intelligence.展开更多
To enhance the adhesion of ceramic coatings in turbine blade Thermal Barrier Coatings(TBCs)systems,Laser Surface Texturing(LST)was employed to create microstructures on the metal bond coat.The bonding conditions and f...To enhance the adhesion of ceramic coatings in turbine blade Thermal Barrier Coatings(TBCs)systems,Laser Surface Texturing(LST)was employed to create microstructures on the metal bond coat.The bonding conditions and failure mechanisms of the ceramic coatings within these microstructures were thoroughly investigated.Femtosecond laser technology was used to fabricate three types of high-quality microstructure grooves:linear,sine wave,and grid patterns.These grooves exhibit uniform morphology,well-defined edges,and smooth inner walls.After ceramic coating deposition,columnar crystal structures grew perpendicularly along the groove walls,completely filling the microstructures and forming an arched support structure that significantly enhances mechanical interlocking and adhesion.Among the different microstructures,grid patterns demonstrated the best adhesion performance.In scratch tests,grid-patterned microstructures exhibited only localized small block spalling under high load conditions,avoiding large-scale delamination.This superior performance is attributed to the ability of grid pattern to effectively distribute stress in multiple directions and prevent crack propagation.By reducing stress concentration and enhancing mechanical interlocking points,grid-patterned microstructures also showed excellent resistance to spallation during thermal cycling,markedly improving the thermal resistance and adhesion of coating.展开更多
Although the etiology of inflammatory bowel disease (IBD) remains unclear,compromised epithelial barrier integrity is believed to promote susceptibility toIBD and be associated with disease severity, suggesting that i...Although the etiology of inflammatory bowel disease (IBD) remains unclear,compromised epithelial barrier integrity is believed to promote susceptibility toIBD and be associated with disease severity, suggesting that improving gut barrierintegrity may palliate or treat IBD. Such a notion gets support from the clinicalfindings that mucosal healing in IBD patients is associated with improvedprognosis, and reduced risk of relapse or colitis-associated cancer. It thereforebecomes critical to understand the intracellular signals that regulate mucosalhealing and gut barrier integrity. Focal adhesion kinase (FAK) is a non-receptortyrosine kinase that critically modulates epithelial cell growth and mobility andhas been associated with carcinogenesis. However, studies also suggest that FAKactivation may promote mucosal healing under conditions of colitis, which shouldreduce the risk of colitis-associated cancer. These findings highlight a potentiallytransformative role for FAK in the context of IBD. Understanding the molecularmechanisms by which FAK influences gut barrier repair and mucosal integritycould offer novel therapeutic avenues for treating IBD and preventing its longtermcomplications. This review focuses on the potential role of FAK in promotingcolitis-associated mucosal healing and the underlying molecular mechanismsdriving these processes, offering critical insights into IBD pathogenesis and therapy.展开更多
Objective:Cytotoxic T lymphocytes(CTLs)play a crucial role in the therapeutic approach to hepatocellular carcinoma(HCC).Recent research has indicated that junctional adhesion molecule-like protein(JAML)enhances the an...Objective:Cytotoxic T lymphocytes(CTLs)play a crucial role in the therapeutic approach to hepatocellular carcinoma(HCC).Recent research has indicated that junctional adhesion molecule-like protein(JAML)enhances the antitumor activity of CD8+T cells.Our study investigates the role of JAML+CD8+T cells in HCC.Methods:We utilized time-of-flight mass cytometry and an orthotopic mouse model of HCC to examine histone modifications in tumor-infiltrating immune cells undergoing immunotherapy.Flow cytometry was used to assess CD4+T cells differentiation and JAML expression in CD8+T cells infiltrating HCC.Correlation analysis revealed a strong positive correlation between lactate dehydrogenase A+(LDHA+)CD4+T cells and JAML+CD8+T cells.Subsequently,we evaluated the therapeutic effects of an agonistic anti-JAML antibody,both alone and combined with immunotherapy.Finally,RNA sequencing was conducted to identify potential regulatory mechanisms.Results:Immunotherapy significantly increased the percentage of CD8+T cells infiltrating HCC and induced histone modifications,such as H3K18 lactylation(H3K18la)in CD4+T cells.Flow cytometry analysis revealed that lactate promotes the differentiation of CD4+T cells into Th1 cells.LDHA,an enzyme that converts pyruvate to lactate,plays a key role in this process.Correlation analysis revealed a strong positive relationship between LDHA+CD4+T cells and JAML+CD8+T cells in patients who responded to immunotherapy.Moreover,high JAML expression in CD8+T cells was associated with a more favorable prognosis.In vivo experiments demonstrated that agonistic anti-JAML antibody therapy reduced tumor volume and significantly prolonged the survival of tumor-bearing mice,independent of the effects of anti-programmed cell death protein ligand-1 antibody(αPD-L1)-mediated immunotherapy.Pathway enrichment analysis further revealed that JAML enhances CTL responses through the oxidative phosphorylation pathway.Conclusions:Activation of JAML enhances CTL responses in HCC treatment,independent ofαPD-L1-mediated immunotherapy,providing a promising strategy for advanced HCC.展开更多
Purpose–This study aims to propose a cooperative adhesion control method for trains with multiple motors electric locomotives.The method is intended to optimize the output torque of each motor,maximize the utilizatio...Purpose–This study aims to propose a cooperative adhesion control method for trains with multiple motors electric locomotives.The method is intended to optimize the output torque of each motor,maximize the utilization of train adhesion within the total torque command,reduce the train skidding/sliding phenomenon and achieve optimal adhesion utilization for each axle,thus realizing the optimal allocation of the multi-motor electric locomotives.Design/methodology/approach–In this study,a model predictive control(MPC)-based cooperative maximum adhesion tracking control method for multi-motor electric locomotives is presented.Firstly,train traction system with multiple motors is constructed in accordance with Newton’s second law.These equations include the train dynamics equations,the axle dynamics equations,and the wheel-rail adhesion coefficient equations.Then,a new MPC-based multi-axle adhesion co-optimization method is put forward.This method calculates the optimal output torque through real-time iteration based on the known reference slip speed to achieve multi-axle co-optimization under different circumstances.Findings–This paper presents a MPC system designed for the cooperative control of multi-axle adhesion.The results indicate that the proposed control system is able to optimize the adhesion of multiple axles under numerous different conditions and achieve the optimal power distribution based on the reduction of train skidding/sliding.Originality/value–This study presents a novel cooperative adhesion tracking control scheme.It is designed for multi-motor electric locomotives,which has rarely been studied before.And simulations are carried out in different conditions,including variable surfaces and motor failing.展开更多
BACKGROUND Regulator of G protein signaling(RGS)proteins participate in tumor formation and metastasis by acting on theα-subunit of heterotrimeric G proteins.The speci-fic effect of RGS,particularly RGS4,on the progr...BACKGROUND Regulator of G protein signaling(RGS)proteins participate in tumor formation and metastasis by acting on theα-subunit of heterotrimeric G proteins.The speci-fic effect of RGS,particularly RGS4,on the progression of gastric cancer(GC)is not yet clear.AIM To explore the role and underlying mechanisms of action of RGS4 in GC develop-ment.METHODS The prognostic significance of RGS4 in GC was analyzed using bioinformatics based public databases and verified by immunohistochemistry and quantitative polymerase chain reaction in 90 patients with GC.Function assays were employed to assess the carcinogenic impact of RGS4,and the mechanism of its possible influence was detected by western blot analysis.A nude mouse xenograft model was established to study the effects of RGS4 on GC growth in vitro.RESULTS RGS4 was highly expressed in GC tissues compared with matched adjacent normal tissues.Elevated RGS4 expression was correlated with increased tumor-node-metastasis stage,increased tumor grade as well as poorer overall survival in patients with GC.Cell experiments demonstrated that RGS4 knockdown suppressed GC cell proliferation,migration and invasion.Similarly,xenograft experiments confirmed that RGS4 silencing significantly inhibited tumor growth.Moreover,RGS4 knockdown resulted in reduced phosphorylation levels of focal adhesion kinase,phosphatidyl-inositol-3-kinase,and protein kinase B,decreased vimentin and N-cadherin,and elevated E-cadherin.CONCLUSION High RGS4 expression in GC indicates a worse prognosis and RGS4 is a prognostic marker.RGS4 influences tumor progression via the focal adhesion kinase/phosphatidyl-inositol-3-kinase/protein kinase B pathway and epithelial-mesenchymal transition.展开更多
Large-area two-dimensional(2D)materials,such as graphene,MoS_(2),WS_(2),h-BN,black phosphorus,and MXenes,are a class of advanced materials with many possible applications.Different applications need different substrat...Large-area two-dimensional(2D)materials,such as graphene,MoS_(2),WS_(2),h-BN,black phosphorus,and MXenes,are a class of advanced materials with many possible applications.Different applications need different substrates,and each substrate may need a different way of transferring the 2D material onto it.Problems such as local stress concentrations,an uneven surface tension,inconsistent adhesion,mechanical damage and contamination during the transfer can adversely affect the quality and properties of the transferred material.Therefore,how to improve the integrity,flatness and cleanness of large area 2D materials is a challenge.In order to achieve high-quality transfer,the main concern is to control the interface adhesion between the substrate,the 2D material and the transfer medium.This review focuses on this topic,and finally,in order to promote the industrial use of large area 2D materials,provides a recipe for this transfer process based on the requirements of the application,and points out the current problems and directions for future development.展开更多
The limited metal-polymer interlaminar property is a significant obstacle to the advancement of Ti/Carbon Fiber(CF)/Polyether Ether Ketone(PEEK)hybrid laminates.We report for the first time a novel method by utilizing...The limited metal-polymer interlaminar property is a significant obstacle to the advancement of Ti/Carbon Fiber(CF)/Polyether Ether Ketone(PEEK)hybrid laminates.We report for the first time a novel method by utilizing the mussel-inspired Polydopamine(PDA)to introduce a strong chemical-physical bonding between titanium and PEEK.The enhanced Fiber-Metal Laminate(FML)exhibits a significant 48.82%enhancement in Interlaminar Shear Strength(ILSS).In addition,it alters the failure mode of the FML from single metal-resin interlaminar delamination to a multi-mechanism,including debonding,delamination of different composite layers,leading to a 28.57%improvement in maximum displacement.展开更多
This paper investigates the adhesive nanocontact behavior of an elastic halfplane indented by a rigid cylindrical indenter,incorporating the simultaneous effects of surface elasticity,couple stresses,and adhesion.The ...This paper investigates the adhesive nanocontact behavior of an elastic halfplane indented by a rigid cylindrical indenter,incorporating the simultaneous effects of surface elasticity,couple stresses,and adhesion.The free surface of the half-plane is modeled by the Steigmann-Ogden surface elasticity theory,while the bulk material behavior is described by the classical couple-stress elasticity theory.The adhesion at the contact interface is characterized by the Maugis-Dugdale(MD)adhesive contact model.Building on the fundamental nonclassical Flamant solution,the governing equations and boundary conditions of the nanocontact problem are reformulated into a system of triple integral equations.These equations are solved numerically by the Gauss-Chebyshev quadratures in combination with an iterative algorithm.The validation against the existing literature confirms the accuracy and robustness of the proposed solution methodology.Comprehensive parametric studies are performed to elucidate the critical roles of surface elasticity and couple stresses in adhesive nanocontact.The numerical results provide insights into the complex interactions among surface,couple-stress,and adhesive effects.Specifically,the interplay between the surface and adhesive effects is predominantly competitive,while the interaction between the couple stresses and adhesion exhibits an intricate nature.The findings highlight the necessity of simultaneously considering surface elasticity,couple stresses,and adhesion in nanoindentation analyses to achieve accurate predictions of material responses.展开更多
Magnesium alloys have gained extensive applications across various industries,including aerospace,transportation,and civil construction,owing to their excellent combinations of high specific strength and stiffness[1]....Magnesium alloys have gained extensive applications across various industries,including aerospace,transportation,and civil construction,owing to their excellent combinations of high specific strength and stiffness[1].However,their lim-ited strength due to the lack of effective strengthening phases has hindered their broader industrial applications[2].Never-theless,it has been challenging to achieve significant strength-ening due to the restricted solubility of alloying elements in magnesium[3].Thus,more and more efforts have been made to explore the concept of secondary phase-reinforced magne-sium alloys[2,4,5],where the secondary phase acts as re-inforcing agents within the magnesium matrix,resembling a composite material.展开更多
Tendon adhesion,a prevalent complication affecting over 30%of patients after a tendon injury or surgery,results in joint stiffness and impaired mobility.Although current treatments facilitate tendon repair,they are of...Tendon adhesion,a prevalent complication affecting over 30%of patients after a tendon injury or surgery,results in joint stiffness and impaired mobility.Although current treatments facilitate tendon repair,they are often insufficient in preventing adhesions and promoting optimal healing outcomes.To address these challenges,we developed an oriented cryostructured silk fibroin bandage(OCSFB)using the directional freeze-casting methodology.In vitro studies demonstrated that OCSFB provided a favorable microenvironment for cell viability,proliferation,and alignment,concurrently upregulating the expression of tendon-specific genes.In a rat Achilles tendon model,OCSFB significantly reduced adhesion formation and improved tendon healing.RNA-seq analysis further revealed modulation of cell adhesion molecules,substantiating its role in tissue regeneration.The integration of silk fibroin biocompatibility with a unique microstructure that facilitates cellular adhesion and proliferation renders OCSFB a promising approach for mitigating tendon adhesions and improving repair outcomes,establishing it as a robust candidate for clinical application.展开更多
Bacterial infection presents formidable challenges that frequently culminate in the malfunction of metal implants.Traditional surface treatment methods struggle to effectively achieve controllable management of bacter...Bacterial infection presents formidable challenges that frequently culminate in the malfunction of metal implants.Traditional surface treatment methods struggle to effectively achieve controllable management of bacterial infections associated with metal implants.To effectively enhance the antibacterial capabilities and preventing bacterial adhesion,electroactive materials have emerged as a groundbreaking strategy for surface modification of metal.By responding to external signals,the electroactive materials can improve antibacterial properties and resistance to bacterial adhesion on the implant surface through harnessing the electrostatic interaction of charges,ion release,oxidation of reactive oxygen species(ROS),electron transfer,and the involvement of cellular immunity.This review delves into the principles of how electroactive materials confer implants with antibacterial properties and antibacterial adhesion,while also summarizing the latest research breakthroughs in their application for surface modification.These strategies successfully strike a balance between the antibacterial and the antimicrobial performance of the implant surface.Lastly,the review examines the limitations and ongoing challenges faced by electroactive material modification technology in implant applications,and sketches out the future trajectory and potential innovative avenues in this promising field.展开更多
Precise solutions for wheel-rail adhesion are important to the traction and braking of the high-speed trains under wet conditions.Current models predominantly rely on Hertzian contact theory assumptions.The present wo...Precise solutions for wheel-rail adhesion are important to the traction and braking of the high-speed trains under wet conditions.Current models predominantly rely on Hertzian contact theory assumptions.The present work proposes a novel non-Hertzian wheel-rail adhesion model to clarify the adhesion mechanisms under wet conditions.The non-Hertzian elastohydrodynamic lubrication(EHL)model was developed to obtain wheel-rail normal contact pressure under wet conditions with rough surfaces.The non-Hertzian extended creep force(ECF)model,which considers the effects of pressure and temperature on the elastic-plastic characteristics of the third body layer(3BL),was used to solve the tangential problems based on wheel-rail normal contact results.The numerical model was also validated by the high-speed wheel-rail adhesion laboratory tests.The wheel-rail rolling contact characteristics at different wheelset lateral displacements are investigated.The results reveal that the distributions of normal pressure,film thickness,tangential stress,and temperature show typical non-Hertzian characteristics.Finally,the effects of train speed and surface roughness on the adhesion characteristics are studied at different lateral displacements.The findings show that the present model can be used for the prediction of high-speed railway adhesion characteristics.展开更多
基金financial support pro-vided by National Natural Science Foundation of China(Grant No.52178402).
文摘The shear adhesive strength at the clay‒metal interfaces serves as a critical parameter for evaluating the soil adhesion and metal interface mudding phenomena.However,its rapid determination remains challenging because of the demanding requirements for high-precision instrumentation and complex calibration procedures.In this study,an integrated framework was presented that combined physical experiments,theoretical approaches,and machine learning to enable the autonomous determination of the shear adhesive strength of soil under multiple influencing factors.We developed an improved particle swarm optimization-optimized ordinary kriging(IPOK)surrogate testing method to enhance the limited experimental datasets,and a lightweight residual neural network(RLNet)was then used for effective intra-and extra-domain predictions.A comprehensive model discussion,comparison,and interpretability analysis were conducted.The results from 64 physical experiments considering the consistency index,normal stress,clay content,rotation rate,and disc material effectively characterized the shear adhesion behaviour of kaolin.The IPOK surrogate experiments successfully replicated the physical data points while enriching the dataset details.The RLNet model trained with IPOK data achieved superior prediction performance,with a root mean square error of 7.491 and a determination coefficient of 0.927 in 16 orthogonal validation tests,and high similarity was attained between the predicted and measured values.A detailed model discussion analysis confirmed the superiority of the IPOK-RLNet framework.This methodology provides a cost-effective rapid analysis technique for assessing clay‒metal interface shear adhesion,significantly reducing laboratory testing requirements and experimental costs while increasing engineering efficiency.
基金funded by the National Natural Science Foundation of China(32472401).
文摘As a specific spoilage organism of seafood under refrigerated temperature conditions,Shewanella spp.tend to form biofilms that exacerbate the occurrence of seafood spoilage.Biofilm-promoting factor A(BpfA)has been reported to promote the adhesion and biofilm formation of Shewanella spp.,but its role in adhesion and biofilm formation of S.putrefaciens under cold stress needs to be further investigated.To better comprehend the effect of BpfA on adhesion and biofilm formation of S.putrefaciens under cold stress(4℃),bacterial adhesion and biofilm phenotype of S.putrefaciens CN32 WT andΔbpfA at 4℃were analyzed and performed transcriptomics.The results showed that the deletion of bpfA had almost no effect on the growth of S.putrefaciens CN32 at 4℃,but weakened the unicellular adhesion capacity of S.putrefaciens CN32 and destabilized the stability of the multicellular adhesion layer.In addition,the biomass of the mature biofilm formed byΔbpfA was merely around 50%of that observed in the mature biofilm of S.putrefaciens CN32 WT,the average thickness and volume of the biofilm decreased by 18%and 27%,respectively,and the composition of the biofilm changed.Transcriptome analysis demonstrated that the deletion of bpfA led to differential expression of genes involved in metabolic pathways such as bacterial chemotaxis,two-component system,tyrosine metabolism,drug metabolism-other enzymes and biofilm formation-Vibrio cholerae,which in turn influenced bacterial adhesion and biofilm formation.Those results advance our acknowledgment of the character of BpfA on adhesion and biofilm formation of S.putrefaciens CN32,which contributes to understanding bacterial adhesion and the control of biofilm formation.
基金financially supported by Mashhad University of Medical Sciences(961726).
文摘Objective:To explore the effects of Punica granatum L.(P.granatum,Shi Liu)seed in the management of peritoneal adhesions(PAs)in rats.Methods:The mature male rats were separated into the following groups,each containing six animals:a sham group without peritoneal adhesion induction,a negative control group,and four intervention groups with both peritoneal adhesion induction and administration of 2 mL of vehicle or 0.1%,0.3%,1%,or 3%w/v P.granatum seed Soxhlet(PSS).Peritoneal adhesions were assessed through macroscopic examination,transforming growth factor-β1(TGF-β1),vascular endothelial growth factor(VEGF),and inflammatory cytokine tumor necrosis factor-α(TNF-α)levels were evaluated using biochemical methods.Results:The findings revealed no notable differences in adhesin scores between the therapeutic and negative control groups,but PSS(1 and 3%w/v)significantly reduced TNF-α,VEGF,and TGF-β1 levels compared with those in the negative control group(all P<.01).Conclusion:The results indicate that PSS is a potential treatment option for intraperitoneal adhesions.
基金supported by the NSF of Shanxi(202303021221168)the Industry-university-research project of Shanxi Datong University(2022CXY10,2022CXY13).
文摘In this paper,our main goal is to study a new mathematical model which describes the frictional contact between a foundation and a deformable body which is composed of viscoplastic materials and where the process is considered dynamic.The contact condition on the normal plane is modeled by a unilateral constraint condition for a version of normal velocity in which the memory effect and the adhesion are considered.On the tangential plane a frictional contact condition is governed by the Clarke subdifferential of a locally Lipschitz function,and the evolution of the bonding field is governed by an ordinary differential equation.We formulate this problem as coupled system that consists of two ordinary differential equations and a variational-hemivariational inequality.Then,the existence,uniqueness and continuous dependence of the solution on the data results concerning the abstract system are established.Finally,we use the abstract results to show the existence and uniqueness of the solution to the contact problem.
基金supported by the National Natural Science Foundation of China(52473033)。
文摘The operational temperature rise of photovoltaic(PV)panels reduces their power generation efficiency and shortens their lifespan.Hygroscopic hydrogel-based evaporative cooling technology provides a promising solution for PV cooling due to high-enthalpy water evaporation.However,current hydrogels remain plagued by cooling interface mismatch and environmental concerns,which limit their practical implementation.Herein,a“green”and self-adhesive hygroscopic hydrogel consisting only of cheap lotus root powder and LiCl is designed,which can form robust interfacial adhesion with PV panels for efficient and durable cooling.Leveraging its compelling hygroscopicity,the hydrogel is able to rapidly capture moisture to recover cooling capacity,thus achieving self-sustained cooling.Besides,the“salting-in”effect brought by LiCl endows the hydrogel with notable softness and self-adhesiveness,which enables it to tightly combine with PV panels to optimize heat conduction and improve cooling efficiency.As a result,under 1.0 kW m^(-2)illumination,a PV temperature drop of 18.2℃ and a cooling power of 358 W m^(-2)were delivered by attaching the hydrogel to the rear of the PV panel,accompanied by a 7.7%improvement in energy efficiency.Overall,this self-sustained passive cooling strategy,activated by the all-natural hydrogel,sheds light on the development of PV thermal management.
基金supported by the National Natural Science Foundation of China(Grant No.32371471).
文摘Systematic understanding of the interaction between cells and their microenvironment is of wide interest.To investigate this interaction,a flexible micropillar array device integrating dual functions of cell behavior regulation and adhesion measurement is developed.Micropillar arrays with high and low densities are designed to explore the role of substrate topography in the behavior of human bone marrow mesenchymal stem cells.In addition,a method is established for quantifying weak cell adhesion forces on the basis of micropillar deflections.The results show that cell cytoplasmic adhesion is greater on a low-density micropillar array than that on a high-density array and is localized mainly in the perinuclear region of the cytoplasm rather than in pseudopods.It is also found that the micropillar array topography facilitates the oriented spreading of cell morphology and pseudopod formation,and a reduction in focal adhesion aggregation and F-actin polarization compared with a flat substrate.Notably,cells cultured on a low-density micropillar array exhibited a higher number of pseudopods,stronger adhesion forces,and greater stiffness compared with those on a high-density array.In summary,this work employs an adhesion force sensor,immunofluorescence staining,and atomic force microscopy to investigate the mechanical properties of cells and elucidate the mechanisms by which micropillar topographical cues regulate the adhesion of mesenchymal stem cells to the substrate.The micropillar array force sensor developed in this study provides an effective tool for simultaneously modulating cell behavior and quantifying adhesion forces,offering valuable insights for biomechanical research.
基金supported by the Wisdom Accumulation and Talent Cultivation Project of Third Xiangya Hosipital of Central South University,China(YX202112).
文摘Objective:Endometrial tuberculosis,which commonly affects women of reproductive age,is a significant cause of intrauterine adhesions(IUA),potentially leading to hypomenorrhea,amenorrhea,and infertility.Hysteroscopic adhesiolysis is the primary treatment for IUA;however,studies specifically addressing its efficacy in tuberculosisinduced IUA remain scarce.This study aims to evaluate the therapeutic outcomes of hysteroscopic adhesiolysis for IUA caused by endometrial tuberculosis.Methods:This retrospective cohort study included patients diagnosed with tuberculosisinduced IUA who underwent hysteroscopic adhesiolysis at the Third Xiangya Hospital of Central South University between May 2014 and October 2022.Clinical data including age,medical history,adhesion severity,surgical treatment,and reproductive outcomes were analyzed.Results:Among 39 patients identified,2 were lost to follow-up.A total of 37 patients were included,with a follow-up duration ranging from 6 months to 9 years.Hypomenorrhea was reported in 24(64.9%)patients,secondary amenorrhea in 10(27.0%)patients,and normal menstruation in 3(8.1%)patients.Most patients presented with primary infertility(59.5%),and only 2(5.4%)had secondary infertility.The median American Fertility Society(AFS)score at initial assessment was 10(range,8−12);8(21.6%)patients had moderate IUA,and 29(78.4%)had severe IUA.A total of 86 surgical procedures were performed across 37 patients,with 27 patients undergoing 2 or more surgeries.Postoperatively,25(67.6%)patients achieved normalization of the uterine cavity,while 12(32.4%)still had a reduced cavity.Only 7(18.9%)patients had a grossly normal endometrium at the final surgery,all of whom had moderate adhesions at the initial procedure.Menstrual flow returned to normal in 12(32.4%)patients,while 25(67.6%)continued to experience hypomenorrhea.Of 29 patients who attempted in vitro fertilization and embryo transfer(IVF-ET),only 6(20.7%)conceived.Among these,4(13.8%)delivered at term via cesarean section;one case was complicated by postpartum hemorrhage due to uterine atony and another by placental adhesion.Conclusion:Endometrial tuberculosis can lead to severe IUA.Hysteroscopic adhesiolysis facilitates cavity restoration and improvement of menstrual conditions,but the overall reproductive outcomes remain suboptimal.
基金supported by the National Key Research&Development Program of China(grant no.2022YFC3500503)the National Natural Science Foundation of China(grant nos.62227807,12374171,12004034,62402041)+2 种基金the Beijing Institute of Technology Research Fund Program for Young Scholars,Chinathe Fundamental Research Funds for the Central Universities(grant nos.2024CX06060)Beijing Youth Talent Lifting Project.
文摘Due to their high mechanical compliance and excellent biocompatibility,conductive hydrogels exhibit significant potential for applications in flexible electronics.However,as the demand for high sensitivity,superior mechanical properties,and strong adhesion performance continues to grow,many conventional fabrication methods remain complex and costly.Herein,we propose a simple and efficient strategy to construct an entangled network hydrogel through a liquid-metal-induced cross-linking reaction,hydrogel demonstrates outstanding properties,including exceptional stretchability(1643%),high tensile strength(366.54 kPa),toughness(350.2 kJ m^(−3)),and relatively low mechanical hysteresis.The hydrogel exhibits long-term stable reusable adhesion(104 kPa),enabling conformal and stable adhesion to human skin.This capability allows it to effectively capture high-quality epidermal electrophysiological signals with high signal-to-noise ratio(25.2 dB)and low impedance(310 ohms).Furthermore,by integrating advanced machine learning algorithms,achieving an attention classification accuracy of 91.38%,which will significantly impact fields like education,healthcare,and artificial intelligence.
基金supported by the National Science and Technology Major Project,China(No.J2019-VII-0013-0153)the Sichuan Science and Technology Program,China(Nos.2021ZDZX0001 and 2021ZDZX0002)。
文摘To enhance the adhesion of ceramic coatings in turbine blade Thermal Barrier Coatings(TBCs)systems,Laser Surface Texturing(LST)was employed to create microstructures on the metal bond coat.The bonding conditions and failure mechanisms of the ceramic coatings within these microstructures were thoroughly investigated.Femtosecond laser technology was used to fabricate three types of high-quality microstructure grooves:linear,sine wave,and grid patterns.These grooves exhibit uniform morphology,well-defined edges,and smooth inner walls.After ceramic coating deposition,columnar crystal structures grew perpendicularly along the groove walls,completely filling the microstructures and forming an arched support structure that significantly enhances mechanical interlocking and adhesion.Among the different microstructures,grid patterns demonstrated the best adhesion performance.In scratch tests,grid-patterned microstructures exhibited only localized small block spalling under high load conditions,avoiding large-scale delamination.This superior performance is attributed to the ability of grid pattern to effectively distribute stress in multiple directions and prevent crack propagation.By reducing stress concentration and enhancing mechanical interlocking points,grid-patterned microstructures also showed excellent resistance to spallation during thermal cycling,markedly improving the thermal resistance and adhesion of coating.
文摘Although the etiology of inflammatory bowel disease (IBD) remains unclear,compromised epithelial barrier integrity is believed to promote susceptibility toIBD and be associated with disease severity, suggesting that improving gut barrierintegrity may palliate or treat IBD. Such a notion gets support from the clinicalfindings that mucosal healing in IBD patients is associated with improvedprognosis, and reduced risk of relapse or colitis-associated cancer. It thereforebecomes critical to understand the intracellular signals that regulate mucosalhealing and gut barrier integrity. Focal adhesion kinase (FAK) is a non-receptortyrosine kinase that critically modulates epithelial cell growth and mobility andhas been associated with carcinogenesis. However, studies also suggest that FAKactivation may promote mucosal healing under conditions of colitis, which shouldreduce the risk of colitis-associated cancer. These findings highlight a potentiallytransformative role for FAK in the context of IBD. Understanding the molecularmechanisms by which FAK influences gut barrier repair and mucosal integritycould offer novel therapeutic avenues for treating IBD and preventing its longtermcomplications. This review focuses on the potential role of FAK in promotingcolitis-associated mucosal healing and the underlying molecular mechanismsdriving these processes, offering critical insights into IBD pathogenesis and therapy.
基金funded by the Major Research Plan of the National Natural Science Foundation of China(No.92159202)the National Key Research and Development Program of China(No.2021YFA1100500)+1 种基金the Leading Innovation Team Project of Hangzhou Medical College(No.CXLJ202401)the Key Research and Development Plan of Zhejiang Provincial Department of Science and Technology(No.2024C03051)。
文摘Objective:Cytotoxic T lymphocytes(CTLs)play a crucial role in the therapeutic approach to hepatocellular carcinoma(HCC).Recent research has indicated that junctional adhesion molecule-like protein(JAML)enhances the antitumor activity of CD8+T cells.Our study investigates the role of JAML+CD8+T cells in HCC.Methods:We utilized time-of-flight mass cytometry and an orthotopic mouse model of HCC to examine histone modifications in tumor-infiltrating immune cells undergoing immunotherapy.Flow cytometry was used to assess CD4+T cells differentiation and JAML expression in CD8+T cells infiltrating HCC.Correlation analysis revealed a strong positive correlation between lactate dehydrogenase A+(LDHA+)CD4+T cells and JAML+CD8+T cells.Subsequently,we evaluated the therapeutic effects of an agonistic anti-JAML antibody,both alone and combined with immunotherapy.Finally,RNA sequencing was conducted to identify potential regulatory mechanisms.Results:Immunotherapy significantly increased the percentage of CD8+T cells infiltrating HCC and induced histone modifications,such as H3K18 lactylation(H3K18la)in CD4+T cells.Flow cytometry analysis revealed that lactate promotes the differentiation of CD4+T cells into Th1 cells.LDHA,an enzyme that converts pyruvate to lactate,plays a key role in this process.Correlation analysis revealed a strong positive relationship between LDHA+CD4+T cells and JAML+CD8+T cells in patients who responded to immunotherapy.Moreover,high JAML expression in CD8+T cells was associated with a more favorable prognosis.In vivo experiments demonstrated that agonistic anti-JAML antibody therapy reduced tumor volume and significantly prolonged the survival of tumor-bearing mice,independent of the effects of anti-programmed cell death protein ligand-1 antibody(αPD-L1)-mediated immunotherapy.Pathway enrichment analysis further revealed that JAML enhances CTL responses through the oxidative phosphorylation pathway.Conclusions:Activation of JAML enhances CTL responses in HCC treatment,independent ofαPD-L1-mediated immunotherapy,providing a promising strategy for advanced HCC.
基金supported by Scientific Research Projects of China Association of Metros(CAMET-KY-2022039)State Key Laboratory of Traction and Control System of EMU and Locomotive(2023YJ386).
文摘Purpose–This study aims to propose a cooperative adhesion control method for trains with multiple motors electric locomotives.The method is intended to optimize the output torque of each motor,maximize the utilization of train adhesion within the total torque command,reduce the train skidding/sliding phenomenon and achieve optimal adhesion utilization for each axle,thus realizing the optimal allocation of the multi-motor electric locomotives.Design/methodology/approach–In this study,a model predictive control(MPC)-based cooperative maximum adhesion tracking control method for multi-motor electric locomotives is presented.Firstly,train traction system with multiple motors is constructed in accordance with Newton’s second law.These equations include the train dynamics equations,the axle dynamics equations,and the wheel-rail adhesion coefficient equations.Then,a new MPC-based multi-axle adhesion co-optimization method is put forward.This method calculates the optimal output torque through real-time iteration based on the known reference slip speed to achieve multi-axle co-optimization under different circumstances.Findings–This paper presents a MPC system designed for the cooperative control of multi-axle adhesion.The results indicate that the proposed control system is able to optimize the adhesion of multiple axles under numerous different conditions and achieve the optimal power distribution based on the reduction of train skidding/sliding.Originality/value–This study presents a novel cooperative adhesion tracking control scheme.It is designed for multi-motor electric locomotives,which has rarely been studied before.And simulations are carried out in different conditions,including variable surfaces and motor failing.
基金Supported by the Fundamental Research Program of Shanxi Province,No.202203021222418Research Program of Shanxi Provincial Health Commission,No.2023061+2 种基金Fundamental Research Cooperation Program of Beijing-Tianjin-Hebei Region of Natural Science Foundation of Tianjin,No.22JCZXJC00140Tianjin Major Science and Technology Project,No.21ZXJBSY00110Tianjin Health and Science and Technology Project,No.TJWJ2024ZK001.
文摘BACKGROUND Regulator of G protein signaling(RGS)proteins participate in tumor formation and metastasis by acting on theα-subunit of heterotrimeric G proteins.The speci-fic effect of RGS,particularly RGS4,on the progression of gastric cancer(GC)is not yet clear.AIM To explore the role and underlying mechanisms of action of RGS4 in GC develop-ment.METHODS The prognostic significance of RGS4 in GC was analyzed using bioinformatics based public databases and verified by immunohistochemistry and quantitative polymerase chain reaction in 90 patients with GC.Function assays were employed to assess the carcinogenic impact of RGS4,and the mechanism of its possible influence was detected by western blot analysis.A nude mouse xenograft model was established to study the effects of RGS4 on GC growth in vitro.RESULTS RGS4 was highly expressed in GC tissues compared with matched adjacent normal tissues.Elevated RGS4 expression was correlated with increased tumor-node-metastasis stage,increased tumor grade as well as poorer overall survival in patients with GC.Cell experiments demonstrated that RGS4 knockdown suppressed GC cell proliferation,migration and invasion.Similarly,xenograft experiments confirmed that RGS4 silencing significantly inhibited tumor growth.Moreover,RGS4 knockdown resulted in reduced phosphorylation levels of focal adhesion kinase,phosphatidyl-inositol-3-kinase,and protein kinase B,decreased vimentin and N-cadherin,and elevated E-cadherin.CONCLUSION High RGS4 expression in GC indicates a worse prognosis and RGS4 is a prognostic marker.RGS4 influences tumor progression via the focal adhesion kinase/phosphatidyl-inositol-3-kinase/protein kinase B pathway and epithelial-mesenchymal transition.
基金the National Key R&D Program of China(2022YFA1505200)the National Natural Science Foundation of China(22472140,22021001)the Fundamental Research Funds for the Central Universities(20720210017 and 20720210009)。
文摘Large-area two-dimensional(2D)materials,such as graphene,MoS_(2),WS_(2),h-BN,black phosphorus,and MXenes,are a class of advanced materials with many possible applications.Different applications need different substrates,and each substrate may need a different way of transferring the 2D material onto it.Problems such as local stress concentrations,an uneven surface tension,inconsistent adhesion,mechanical damage and contamination during the transfer can adversely affect the quality and properties of the transferred material.Therefore,how to improve the integrity,flatness and cleanness of large area 2D materials is a challenge.In order to achieve high-quality transfer,the main concern is to control the interface adhesion between the substrate,the 2D material and the transfer medium.This review focuses on this topic,and finally,in order to promote the industrial use of large area 2D materials,provides a recipe for this transfer process based on the requirements of the application,and points out the current problems and directions for future development.
基金the financial supports of Fundamental Research Funds for the Central Universities,China(Nos.YWF-23-L-1012,YWF-22-L-1017)。
文摘The limited metal-polymer interlaminar property is a significant obstacle to the advancement of Ti/Carbon Fiber(CF)/Polyether Ether Ketone(PEEK)hybrid laminates.We report for the first time a novel method by utilizing the mussel-inspired Polydopamine(PDA)to introduce a strong chemical-physical bonding between titanium and PEEK.The enhanced Fiber-Metal Laminate(FML)exhibits a significant 48.82%enhancement in Interlaminar Shear Strength(ILSS).In addition,it alters the failure mode of the FML from single metal-resin interlaminar delamination to a multi-mechanism,including debonding,delamination of different composite layers,leading to a 28.57%improvement in maximum displacement.
基金Project supported by the National Natural Science Foundation of China(No.12072072)。
文摘This paper investigates the adhesive nanocontact behavior of an elastic halfplane indented by a rigid cylindrical indenter,incorporating the simultaneous effects of surface elasticity,couple stresses,and adhesion.The free surface of the half-plane is modeled by the Steigmann-Ogden surface elasticity theory,while the bulk material behavior is described by the classical couple-stress elasticity theory.The adhesion at the contact interface is characterized by the Maugis-Dugdale(MD)adhesive contact model.Building on the fundamental nonclassical Flamant solution,the governing equations and boundary conditions of the nanocontact problem are reformulated into a system of triple integral equations.These equations are solved numerically by the Gauss-Chebyshev quadratures in combination with an iterative algorithm.The validation against the existing literature confirms the accuracy and robustness of the proposed solution methodology.Comprehensive parametric studies are performed to elucidate the critical roles of surface elasticity and couple stresses in adhesive nanocontact.The numerical results provide insights into the complex interactions among surface,couple-stress,and adhesive effects.Specifically,the interplay between the surface and adhesive effects is predominantly competitive,while the interaction between the couple stresses and adhesion exhibits an intricate nature.The findings highlight the necessity of simultaneously considering surface elasticity,couple stresses,and adhesion in nanoindentation analyses to achieve accurate predictions of material responses.
基金supported by the Guangdong Major Project of Basic and Applied Basic Research(No.2020B0301030006)the Guangdong Basic and Applied Basic Research Foundation[Grant No.2021B1515120071]+1 种基金R.Shi would like to thank the financial support from the open research fund of Songshan Lake Materials Laboratory(2021SLABFK06)start-up funding from Harbin Institute of Technology(Shenzhen).
文摘Magnesium alloys have gained extensive applications across various industries,including aerospace,transportation,and civil construction,owing to their excellent combinations of high specific strength and stiffness[1].However,their lim-ited strength due to the lack of effective strengthening phases has hindered their broader industrial applications[2].Never-theless,it has been challenging to achieve significant strength-ening due to the restricted solubility of alloying elements in magnesium[3].Thus,more and more efforts have been made to explore the concept of secondary phase-reinforced magne-sium alloys[2,4,5],where the secondary phase acts as re-inforcing agents within the magnesium matrix,resembling a composite material.
基金sponsored by the National Natural Science Foundation of China(Nos.52235007,T2121004,and 52325504)the Key R&D Program of Zhejiang(No.2024SSYS0027)+1 种基金the National Key Research and Development Program of China(Nos.2024YFB4607700 and 2024YFB4607703)the China National Postdoctoral Program for Innovative Talents(No.BX20240312)。
文摘Tendon adhesion,a prevalent complication affecting over 30%of patients after a tendon injury or surgery,results in joint stiffness and impaired mobility.Although current treatments facilitate tendon repair,they are often insufficient in preventing adhesions and promoting optimal healing outcomes.To address these challenges,we developed an oriented cryostructured silk fibroin bandage(OCSFB)using the directional freeze-casting methodology.In vitro studies demonstrated that OCSFB provided a favorable microenvironment for cell viability,proliferation,and alignment,concurrently upregulating the expression of tendon-specific genes.In a rat Achilles tendon model,OCSFB significantly reduced adhesion formation and improved tendon healing.RNA-seq analysis further revealed modulation of cell adhesion molecules,substantiating its role in tissue regeneration.The integration of silk fibroin biocompatibility with a unique microstructure that facilitates cellular adhesion and proliferation renders OCSFB a promising approach for mitigating tendon adhesions and improving repair outcomes,establishing it as a robust candidate for clinical application.
基金financially supported by the National Key Research and Development Program of China(Nos.2022YFC2406000 and 2021YFC2400402)the National Natural Science Foundation of China(Nos.52101285,51932002,U21A2055 and U22A20160)
文摘Bacterial infection presents formidable challenges that frequently culminate in the malfunction of metal implants.Traditional surface treatment methods struggle to effectively achieve controllable management of bacterial infections associated with metal implants.To effectively enhance the antibacterial capabilities and preventing bacterial adhesion,electroactive materials have emerged as a groundbreaking strategy for surface modification of metal.By responding to external signals,the electroactive materials can improve antibacterial properties and resistance to bacterial adhesion on the implant surface through harnessing the electrostatic interaction of charges,ion release,oxidation of reactive oxygen species(ROS),electron transfer,and the involvement of cellular immunity.This review delves into the principles of how electroactive materials confer implants with antibacterial properties and antibacterial adhesion,while also summarizing the latest research breakthroughs in their application for surface modification.These strategies successfully strike a balance between the antibacterial and the antimicrobial performance of the implant surface.Lastly,the review examines the limitations and ongoing challenges faced by electroactive material modification technology in implant applications,and sketches out the future trajectory and potential innovative avenues in this promising field.
基金Project(52372391)supported by the National Natural Science Foundation of China。
文摘Precise solutions for wheel-rail adhesion are important to the traction and braking of the high-speed trains under wet conditions.Current models predominantly rely on Hertzian contact theory assumptions.The present work proposes a novel non-Hertzian wheel-rail adhesion model to clarify the adhesion mechanisms under wet conditions.The non-Hertzian elastohydrodynamic lubrication(EHL)model was developed to obtain wheel-rail normal contact pressure under wet conditions with rough surfaces.The non-Hertzian extended creep force(ECF)model,which considers the effects of pressure and temperature on the elastic-plastic characteristics of the third body layer(3BL),was used to solve the tangential problems based on wheel-rail normal contact results.The numerical model was also validated by the high-speed wheel-rail adhesion laboratory tests.The wheel-rail rolling contact characteristics at different wheelset lateral displacements are investigated.The results reveal that the distributions of normal pressure,film thickness,tangential stress,and temperature show typical non-Hertzian characteristics.Finally,the effects of train speed and surface roughness on the adhesion characteristics are studied at different lateral displacements.The findings show that the present model can be used for the prediction of high-speed railway adhesion characteristics.
