The revolution of science and technology in the new era is rising.New industries,formats,and models led by information technology are emerging.Scientific research has entered the fourth data-intensive paradigm.As an i...The revolution of science and technology in the new era is rising.New industries,formats,and models led by information technology are emerging.Scientific research has entered the fourth data-intensive paradigm.As an important part of the science and technology innovation system,universities also have new requirements for their scientific research management system.In this article,it is suggested that the efficiency and quality of scientific research management in universities could be enhanced by reconstructing the organizational structure of scientific research management,improve the service capabilities of scientific research managers,perfecting the scientific research evaluation system,and innovating the management model of cross-research teams.展开更多
A new approach referred as“the network modeling method”was developed by the authors to analyze the behaviors of marine structures.In this paper the method is briefly described and applied to predict the loads acting...A new approach referred as“the network modeling method”was developed by the authors to analyze the behaviors of marine structures.In this paper the method is briefly described and applied to predict the loads acting on the connectors between the two modules of the Scientific Research and Demonstration Platform(SRDP),which was deployed in a complicated wave environment near islands and reefs in South China Sea.Based on this method,the response amplitude operators(RAOs)of the connector loads of the SRDP in regular waves,and the time variations of the connector loads of the SRDP in an on-site measured random sea state are predicted and presented.The significant stresses at 20 spots of the local connection structure induced by the connector loads in the sea state are further calculated.The comparisons between the predicted and the on-site measured stresses confirm that the network modeling method is feasible to some extent and especially useful for design of the connectors’arrangement,estimation of the connector loads and the related structural safety of a multi-module floating structure in early design stage.展开更多
Design of a very large floating structure(VLFS)deployed near islands and reefs,different from those in the open sea,inevitably faces new technical challenges including numerical analysis methods.In this paper,a direct...Design of a very large floating structure(VLFS)deployed near islands and reefs,different from those in the open sea,inevitably faces new technical challenges including numerical analysis methods.In this paper,a direct coupling analysis method(DCAM)has been established based on the Boussinesq equations and the three-dimensional hydroelasisity theory with Rankine source method to analyze the responses of a VLFS in shallow sea with complicated geographical environment.Model tests have been carried out to validate the DCAM.To further verify the numerical methods and investigate the performance of such a VLFS,a“Scientific Research and Demonstration Platform(SRDP)”was built and deployed in 2019 at the site about 1000 m off an island with water depth around 40m in South China Sea.It is a simplified small model of a two-module semi-submersible-type VLFS.The numerical simulation of its responses on severe waves with focus on motions and connector forces is conduct by DCAM,and compared with the on-site measurements.Good agreement has been achieved.This approves the DCAM as a feasible tool for design and safety assessment of a VLFS deployed near islands and reefs.展开更多
A mooring system has been designed for the position keeping of a two-module semi-submersible platform which is connected by hinge-type connectors.Under the excitation of ocean waves,the relative motion between the two...A mooring system has been designed for the position keeping of a two-module semi-submersible platform which is connected by hinge-type connectors.Under the excitation of ocean waves,the relative motion between the two modules can be significant.It is therefore no longer adequate to model the platform as a single rigid body in the analysis of the performance of the mooring system.In this study,an analysis method has been developed based on the three-dimensional frequency domain hydroelasticity theory in conjunction with the time domain quasi-static analysis method of mooring actions,which takes into account of the coupling effect of the platform motion and mooring tension.The proposed method is verified by comparing the numerical results with the measured data obtained from the on-site measurements.The comparison shows a good agreement,and demonstrates the feasibility and effectiveness of the proposed method for the analysis of the module responses and mooring tensions of multi-module floating platforms.展开更多
This paper focuses on how technology services can help small and medium-sized enterprises(SMEs)overcome the digital transformation dilemma of“cannot transform(lack of know-how),dare not transform(fear of risk),and ha...This paper focuses on how technology services can help small and medium-sized enterprises(SMEs)overcome the digital transformation dilemma of“cannot transform(lack of know-how),dare not transform(fear of risk),and have no money to transform(lack of funds).”Using literature analysis and multiple case comparisons,the study summarizes five major categories of technology services:technical support,consulting and planning,training and empowerment,resource integration,and financing connectivity.It constructs a“service–capability–performance”catalytic framework.Tracking of 58 enterprises in the Yangtze River Delta reveals that resource integration contributes the most to digital maturity,with absorptive capacity playing a significant mediating role;the configuration of“high technology services+high absorptive capacity+high environmental dynamism”is a sufficient condition for high transformation performance.Based on these findings,countermeasures are proposed,including improving the technology service system,strengthening government-industry-academia collaboration,and optimizing funding and talent supply,providing replicable experience for SMEs,governments,and technology service institutions.展开更多
The potential application of Huangqi(Astragali Radix)in the treatment of diabetes mellitus(DM)has garnered increasing attention.β-cell dysfunction is one of the core mechanisms in the pathogenesis of DM and effective...The potential application of Huangqi(Astragali Radix)in the treatment of diabetes mellitus(DM)has garnered increasing attention.β-cell dysfunction is one of the core mechanisms in the pathogenesis of DM and effectively protecting and restoring pancreaticβ-cell function remains a key challenge in DM prevention and treatment.Studies have shown that the active components of Huangqi(Astragali Radix)can alleviate glucolipotoxicity-inducedβ-cell damage by promoting glucose uptake mediated by glucose transporter 4(GLUT-4),inhibiting the Wnt1/β-catenin signaling pathway to reduce lipid deposition in liver and pancreatic tissues and upregulating peroxisome proliferator-activated receptorα(PPARα)gene expression.Additionally,Huangqi(Astragali Radix)can reduce cell apoptosis by mitigating endoplasmic reticulum stress,suppress pyroptosis via the NF-κB/NLRP3/TXNIP signaling pathway,and inhibit ferroptosis and autophagy to decreaseβ-cell death.Furthermore,Huangqi(Astragali Radix)can promoteβ-cell proliferation by modulating dedifferentiation and transdifferentiation,improve the islet microenvironment by regulating immune function and reducing M1 macrophage polarization,and may delayβ-cell senescence.This review summarizes the research progress of active ingredients in Huangqi(Astragali Radix)in protecting pancreaticβ-cell,which provides new insights and a scientific basis for its future application in DM prevention and treatment.展开更多
The influences of different factors,including whether the transverse frames are actually built,longitudinal and transverse welding residual stresses,and unloaded edge boundaries,on the ultimate strength and failure mo...The influences of different factors,including whether the transverse frames are actually built,longitudinal and transverse welding residual stresses,and unloaded edge boundaries,on the ultimate strength and failure mode of a real hull bottom full-scale stiffened plate under axial compression and lateral pressure are investigated via numerical analysis.Result shows that the failure mode of the stiffened plate under axial compression is the tripping of the stiffeners.Whether transverse frames are built has little effect on the ultimate strength of the stiffened plate under axial compression,which can be replaced by the degree of freedom constraint.However,when lateral pressure is present,the transverse frame cannot be simply replaced by a free-degree constraint.The longitudinal residual stress has a greater effect on the ultimate strength,whereas the effect of the transverse residual stress is smaller.Stronger unloaded edge boundary conditions can slightly enhance the stiffness and ultimate strength of the stiffened plate.Under combined axial compression and lateral pressure,the failure mode of stiffened plates changes from the tripping of stiffeners to beam-column failure,as the lateral pressure increases.The ability of stiffened plates in which transverse frames are actually built out to resist beam-column shape deformation becomes weaker with lower ultimate strength.Stronger unloaded edge boundary conditions can improve the ability of stiffened plates to resist beam-column deformation and increase the ultimate strength.展开更多
In the process of developing oil and gas resources in the Arctic,the impact of icebergs can pose a considerable threat to the structural safety of semi-submersible mooring platforms in ice regions.On the basis of the ...In the process of developing oil and gas resources in the Arctic,the impact of icebergs can pose a considerable threat to the structural safety of semi-submersible mooring platforms in ice regions.On the basis of the arbitrary Lagrangian Eulerian(ALE)algorithm,a numerical model for the interaction between an iceberg and a semi-submersible mooring platform is built in this work.First,a mooring system with a link element is designed and validated.An ice material model for the target iceberg is built and validated.A numerical model for the interaction between an iceberg and a semi-submersible mooring platform is then built.A parametric study(cable angle,tension angle and number of cables)is carried out to study the performance of the mooring system.The collision process between the semi-submersible mooring platform and the iceberg in the polar marine environment can be predicted by the present numerical model,and then the optimal mooring arrangement scheme can be obtained.The research results in this work can provide a reference for the design of mooring systems.展开更多
In this essay,by summarizing the research progress and achievements of various scholars at home and abroad in recent years on the material properties and corrosion resistance of magnesium phosphate cement(MPC),we revi...In this essay,by summarizing the research progress and achievements of various scholars at home and abroad in recent years on the material properties and corrosion resistance of magnesium phosphate cement(MPC),we review the factors influencing on the properties of MPC,and analyze the effects of raw materials,retarders,and admixtures on the properties of MPC.Two different hydration mechanisms of MPC are discussed,and finally the research progress of MPC in the field of anti-corrosion coatings for steel and ordinary concrete(OPC)is highlighted,and suggestions and prospects are given.展开更多
Objective:To determine the safety and the role of modulating cytokines and proteases in the immune response to intravesical Bacillus Calmette-Guérin(BCG)when primed with systemic intradermal BCG.Methods:Phase 1 a...Objective:To determine the safety and the role of modulating cytokines and proteases in the immune response to intravesical Bacillus Calmette-Guérin(BCG)when primed with systemic intradermal BCG.Methods:Phase 1 and mechanistic longitudinal,prospective,single-blind randomized study(NCT04806178).Twenty-one non-muscle invasive urothelial bladder cancer patients undergoing intravesical adjuvant BCG after transurethral resection of bladder tumor(TURBT)in a teaching hospital between September 2021 and April 2023 were randomized to 0.1 mL of intradermal BCG vaccine or placebo(0.9%saline)administered 15 days before the start of intravesical BCG therapy.Blood samples were evaluated mechanistically regarding eight cytokines serum levels interferon-induced transmembrane protein 3 Gene(IFITM3),Interleukin 1 beta(IL1-BETA),interleukin-2 receptor alpha chain(IL2 RA),Interleukin 6(IL 6),Interleukin 10(IL 10),Tumor necrosis factor alpha(TNF-α),Interferon-β,AXL,and one protease CASPASE 8.Results:After 1 exclusion,twenty patients were randomized to intradermal BCG(n=11)and intradermal placebo(n=9).There was no difference in adverse effects emerging from the intravesical Onco-BCG therapy,and no difference in the expression of the cytokines and proteases analyzed between control and intervention,and over time.Conclusions:Intradermal BCG administration before intravesical application was safe,with no increase in adverse effects.It also does not seem to change the analyzed targets during the intravesical induction-phase BCG.Other immune targets should be explored in the future.The Brazilian tuberculosis-endemic status,where BCG vaccination is mandatory,might have affected the results.展开更多
Background:Hua-Yi-Jie-Du formula(HYJD)is a traditional Chinese medicine that has proven effective against viral pneumonia and was extensively used during the COVID-19 pandemic.This study investigates how HYJD influenc...Background:Hua-Yi-Jie-Du formula(HYJD)is a traditional Chinese medicine that has proven effective against viral pneumonia and was extensively used during the COVID-19 pandemic.This study investigates how HYJD influences group 2 innate lymphoid cell(ILC2)and nucleotide oligomerization domain(NOD)-like receptor protein 3(NLRP3)inflammasome activation in a mouse model of viral pneumonia.Methods:A mouse model of viral pneumonia was established through the administration of polyinosinic-polycytidylic acid(poly(I:C))via nasal drops.Histopathological analysis of lung tissue was conducted,alongside enzyme-linked immunosorbent assay to quantify cytokine levels in serum and bronchoalveolar lavage fluid(BALF).Flow cytometry was employed to detect ILC2 cells in lung tissue and spleen,while immunofluorescence techniques were utilized to visualize ILC2 cells in lung tissue.Transcriptomic sequencing was performed,and the results were validated using qRT-PCR and western blot analysis.Results:HYJD significantly ameliorated inflammatory infiltration in lung tissue,decreased mucus protein secretion,and reduced the serum levels of inflammatory cytokines interleukin(IL)-1β,IL-6,and tumor necrosis factor-alpha(TNF-α).Additionally,it lowered the expression of cytokines IL-4,IL-5,IL-13,IL-25,thymic stromal lymphopoietin(TSLP),and IL-33 in BALF,and reduced the differentiation of ILC2 cells in both lung tissue and spleen.Transcriptomic analysis and experimental validation revealed that HYJD downregulated the expression of NLRP3 related genes and proteins within the NOD-like receptor signaling pathway.Conclusion:The mechanism by which HYJD intervenes in acute lung injury associated with viral pneumonia may involve the reduction of ILC2 cells differentiation and the inhibition of NLRP3 activation.展开更多
The dynamic characteristics of the track system can directly affect its service performance and failure process.To explore the load characteristics and dynamic response of the track system under the dynamic loads from...The dynamic characteristics of the track system can directly affect its service performance and failure process.To explore the load characteristics and dynamic response of the track system under the dynamic loads from the rack vehicle in traction conditions,a systematic test of the track subsystem was carried out on a large-slope test line.In the test,the bending stress of the rack teeth,the wheel-rail forces,and the acceleration of crucial components in the track system were measured.Subsequently,a detailed analysis was conducted on the tested signals of the rack railway track system in the time domain and the time-frequency domains.The test results indicate that the traction force significantly affects the rack tooth bending stress and the wheel-rail forces.The vibrations of the track system under the traction conditions are mainly caused by the impacts generated from the gear-rack engagement,which are then transferred to the sleepers,the rails,and the ballast beds.Furthermore,both the maximum stress on the racks and the wheel-rail forces measured on the rails remain below their allowable values.This experimental study evaluates the load characteristics and reveals the vibration characteristics of the rack railway track system under the vehicle’s ultimate load,which is very important for the load-strengthening design of the key components such as racks and the vibration and noise reduction of the track system.展开更多
Activation of spinal cord neural stem cells(NSCs)and subsequent neurogenesis holds a promising alternative for spinal cord injury(SCI)repair.Our previous study demonstrated that complement C3a,derived from reactive as...Activation of spinal cord neural stem cells(NSCs)and subsequent neurogenesis holds a promising alternative for spinal cord injury(SCI)repair.Our previous study demonstrated that complement C3a,derived from reactive astrocytes,inhibits NSC proliferation by suppressing protein aggregate clearance through the deubiquitinating enzyme ubiquitin carboxy-terminal hydrolase L1(UCHL1)-proteasome system post-SCI.However,the potential molecular mechanism by which C3a modulates NSC activation via this pathway remains unclear.Here,we revealed that C3a/C3a receptor(C3aR)signaling activated NF-κB p65,which in turn inhibited Nrf2 activity and UCHL1 expression,resulting in diminished proteasome activity and the accumulation of protein aggregates,and ultimately impaired NSC activation.Both knockdown of NF-κB p65 and Nrf2 upregulation restored UCHL1 expression and proteasome activity in vitro,promoting NSC activation by enhancing protein aggregate clearance.Mechanistically,we found that NF-κB p65 regulated Nrf2 activity through a dual mechanism:(1)promoting Keap1-dependent ubiquitination and proteasome degradation of Nrf2;(2)inhibiting protein kinase C-mediated Nrf2 phosphorylation and nuclear translocation.Using the dual-luciferase reporter assay and chromatin immunoprecipitation(ChIP)analysis,we further identified UCHL1 as a direct transcriptional target of Nrf2.Importantly,in vivo experiments using SCI mice confirmed that either C3aR blockade,NF-κB p65 knockdown,or Nrf2 overexpression could rescue SCI-induced UCHL1 downregulation.Together,this study uncovers the C3a-NF-κB p65-Nrf2-UCHL1-proteasome axis as a critical regulator of NSC activation after SCI.This may provide novel molecular targets and intervention strategies for SCI repair.展开更多
Significant diurnal temperature variations in mountainous rack railways cause stiffness mismatches between the rack structure and simply supported bridges,leading to critical failures like bolt loosening and rack frac...Significant diurnal temperature variations in mountainous rack railways cause stiffness mismatches between the rack structure and simply supported bridges,leading to critical failures like bolt loosening and rack fractures.This study develops a dynamic model of the vehicle-rack-bridge system based on train-track-bridge interaction theory,integrating gear-rack meshing and wheel-rail contact mechanisms.The model analyzes the dynamic response of bridges with varying spans under combined thermal and dynamic loading.Numerical simulations,conducted using finite element analysis,reveal peak vibration accelerations of 1.3 m/s^(2)for the rack,3.0 m/s^(2)for the rail,1.2 m/s^(2)for the sleeper,and 0.1 m/s^(2)for the bridge,with maximum stresses of 3 MPa in the rack,8 MPa in the rail,and 25 MPa in connecting bolts.The results show significant span-dependent amplification of stress and strain in the rack system under thermo-mechanical loading,exceeding material strength limits at 60-meter spans.An innovative elastic connection method is proposed to mitigate stress concentrations effectively,en-hancing system durability.This study introduces a novel approach to modeling complex thermo-mechanical interactions in rack railway systems,validated through extensive simulations,and provides a practical solution for improving structural resilience,offering theoretical guidance for optimizing rack-bridge system design to ensure operational safety in extreme environmental conditions.展开更多
Community detection is a fundamental problem in network analysis for identifying densely connected node clusters,with successful applications in diverse fields like social networks,recommendation systems,biology,and c...Community detection is a fundamental problem in network analysis for identifying densely connected node clusters,with successful applications in diverse fields like social networks,recommendation systems,biology,and cyberattack detection.Overlapping community detection refers to the case of a node belonging to multiple communities simultaneously,which is a much more meaningful and challenging task.Graph representation learning with Evolutionary Computation has been studied well in overlapping community detection to deal with complex network structures and characteristics.However,most of them focus on searching the entire solution space,which can be inefficient and lead to inadequate results.To overcome the problem,a structural feature node extraction method is first proposed that can effectively map a network into a structural embedding space.Thus,nodes within the network are classified into hierarchical levels based on their structural feature strength,and only nodes with relatively high strength are considered in subsequent search steps to reduce the search space.Then,a maximal-clique representation method is employed on the given vertex set to identify overlapping nodes.A hybrid clique-based multi-objective evolutionary algorithmwith decomposition method is designed to address cliques and the remaining unexplored nodes separately.The number of communities generated with this allocation method is closer to the actual partition count with high division quality.Experimental results on nine usually used real-world networks,five synthetic networks,and two large-scale networks demonstrate the effectiveness of the proposed methodology in terms of community quality and algorithmic efficiency,compared to traditional,MOEA-based,and graph embedding-based community detection algorithms.展开更多
Wetting deformation in earth-rockfill dams is a critical factor influencingdam safety.Although numerous mathematical models have been developed to describe this phenomenon,most of them rely on empirical formulations a...Wetting deformation in earth-rockfill dams is a critical factor influencingdam safety.Although numerous mathematical models have been developed to describe this phenomenon,most of them rely on empirical formulations and lack prior knowledge of model parameters,which is essential for Bayesian parameter inversion to enhance accuracy and reduce uncertainty.This study introduces a datadriven approach to establishing prior knowledge of earth-rockfill dams.Driving factors are utilized to determine the potential range of model parameters,and settlement changes within this range are calculated.The results are iteratively compared with actual monitoring data until the calculated range encompasses the observed data,thereby providing prior knowledge of the model parameters.The proposed method is applied to the right-bank earth-rockfilldam of Danjiangkou.Employing a Gibbs sample size of 30,000,the proposed method effectively calibrates the prior knowledge of the wetting model parameters,achieving a root mean square error(RMSE)of 5.18 mm for the settlement predictions.By comparison,the use of non-informative priors with sample sizes of 30,000 and 50,000 results in significantly larger RMSE values of 11.97 mm and 16.07 mm,respectively.Furthermore,the computational efficiencyof the proposed method is demonstrated by an inversion computation time of 902 s for 30,000 samples,which is notably shorter than the 1026 s and 1558 s required for noninformative priors with 30,000 and 50,000 samples,respectively.These findingsunderscore the superior performance of the proposed approach in terms of both prediction accuracy and computational efficiency.These results demonstrate that the proposed method not only improves the predictive accuracy but also enhances the computational efficiency,enabling optimal parameter identificationwith reduced computational effort.This approach provides a robust and efficientframework for advancing dam safety assessments.展开更多
AIM:To compare the tear film quantity and stability parameters in keratoconus(KCN)and normal eyes using test breakup time(TBUT),noninvasive TBUT(NITBUT),and Schirmer test.METHODS:All participants(n=166),including pati...AIM:To compare the tear film quantity and stability parameters in keratoconus(KCN)and normal eyes using test breakup time(TBUT),noninvasive TBUT(NITBUT),and Schirmer test.METHODS:All participants(n=166),including patients with KCN and age-matched healthy individuals with normal corneas,were recruited from those referred to Farabi Eye Hospital,Iran,in 2023.To better account for genetic and environmental factors,the control group comprised healthy individuals who were relatives of KCN patients and had normal corneal topography.Tear quantity parameters were evaluated in the following order:NITBUT,TBUT,and Schirmer tests.RESULTS:The mean age of cases in KCN(61.7%males)and normal(63.5%males)participants was 27.54±5.44y(range 19 to 38)and 27.52±5.63y(range 20 to 38),respectively(P=0.976).NIBUT,TBUT,and Schirmer’s tests were significantly lower in KCN group compared to normal controls(all P<0.001).The mean difference for NIBUT was-7.81s(P<0.001),and for TBUT was-7.61s(P<0.001).Schirmer test values were also significantly lower in the KCN group,with a mean difference of-5.61 mm compared to normal people(P<0.001).CONCLUSION:Our findings demonstrate significant tear film impairment in KCN.The reductions in NIBUT,TBUT and Schirmer scores highlight an underlying tear film dysfunction in KCN that extends beyond the morphological changes of the cornea.展开更多
Sporosarcina pasteurii was employed as the strain,with an in-situ magnetization construction,to obtain magnetic microorganisms and oriented self-healing mortar specimens based on them.The magnetic field was used to ac...Sporosarcina pasteurii was employed as the strain,with an in-situ magnetization construction,to obtain magnetic microorganisms and oriented self-healing mortar specimens based on them.The magnetic field was used to achieve the directional migration of magnetic microorganisms during the oriented selfhealing of mortar cracks,improving the rate of self-healing of cracks.The experimental results demonstrate that the magnetic microorganisms are composed of Fe_(3)O_(4)nanosheets attached to the surface of Sporosarcina pasteurii,whose mineralization products are comprised of vaterite primarily.Compared with the pure microbial group,the magnetic microbial group exhibits a faster repair rate,shortening the repair time required to achieve an area repair efficiency of over 90%from 28 days to 14 days,thereby doubling the repair rate.Meanwhile,the area repair efficiency of the magnetic microbial group at 7,14,and 28 days are increased by 50.3%,11.2%,and 4.6%,respectively,compared to the pure microbial group,which are due to the magnetic microorganisms'superior directional migration and mineralization ability,exceeding that of the ordinary microorganisms.展开更多
The newly formulated non-Newtonian rivulet flows streaming down an inclined planar surface,with additional periodic perturbations arising from the application of the 2nd Stokes problem to the investigation of rivulet ...The newly formulated non-Newtonian rivulet flows streaming down an inclined planar surface,with additional periodic perturbations arising from the application of the 2nd Stokes problem to the investigation of rivulet dynamics,are demonstrated in the current research.Hereby,the 2nd Stokes problem assumes that the surface,with a thin shared layer of the fluid on it,oscillates in a harmonic manner along the x-axis of the rivulet flow,which coincides with the main flow direction streaming down the underlying surface.We obtain the exact extension of the rivulet flow family,clarifying the structure of the pressure field,which fully absorbs the arising perturbation.The profile of the velocity field is assumed to be Gaussian-type with a non-zero level of plasticity.Hence,the absolutely non-Newtonian case of the viscoplastic flow solution,which satisfies the motion and continuity equations,is considered(with particular cases of exact solutions for pressure).The perturbed governing equations of motion for rivulet flows then result in the Riccati-type ordinary differential equation(ODE),describing the dynamics of the coordinate x(t).The approximated schematic dynamics are presented in graphical plots.展开更多
This paper examines a model that combines vortex generators and leading-edge tubercles for controlling the laminar separation bubble(LSB)over an airfoil at low Reynolds numbers(Re).This new concept of passive flow con...This paper examines a model that combines vortex generators and leading-edge tubercles for controlling the laminar separation bubble(LSB)over an airfoil at low Reynolds numbers(Re).This new concept of passive flow control technique utilizing a tubercle and vortex generator(VG)close to the leading edge was analyzed numerically for a NACA0015 airfoil.In this study,the Shear Stress Transport(SST)turbulence model was employed in the numerical modelling.Numerical modelling was completed using the ANSYS-Fluent 18.2 solver.Analyses were conducted to investigate the flow pattern and understand the underlying LSB control phenomena that enabled the new passive flow control method to provide this significant performance benefit.The findings indicated that the new concept of passive flow control technique suppressed the formation of an LSB at the suction surface of the NACA0015 airfoil,resulting in a higher lift coefficient and improved aerodynamic performance.Improvements in LSB dynamics and aerodynamic performance through the passive flow control method lead to increased energy output and enhanced stability.展开更多
文摘The revolution of science and technology in the new era is rising.New industries,formats,and models led by information technology are emerging.Scientific research has entered the fourth data-intensive paradigm.As an important part of the science and technology innovation system,universities also have new requirements for their scientific research management system.In this article,it is suggested that the efficiency and quality of scientific research management in universities could be enhanced by reconstructing the organizational structure of scientific research management,improve the service capabilities of scientific research managers,perfecting the scientific research evaluation system,and innovating the management model of cross-research teams.
基金supported by the National Natural Science Foundation of China(Grant Nos.11702088,11902084)supported by the Ministry of Industry and Information Technology(Grant No.[2016]22)the Ministry of Science and Technology(Grant No.2013CB36100).
文摘A new approach referred as“the network modeling method”was developed by the authors to analyze the behaviors of marine structures.In this paper the method is briefly described and applied to predict the loads acting on the connectors between the two modules of the Scientific Research and Demonstration Platform(SRDP),which was deployed in a complicated wave environment near islands and reefs in South China Sea.Based on this method,the response amplitude operators(RAOs)of the connector loads of the SRDP in regular waves,and the time variations of the connector loads of the SRDP in an on-site measured random sea state are predicted and presented.The significant stresses at 20 spots of the local connection structure induced by the connector loads in the sea state are further calculated.The comparisons between the predicted and the on-site measured stresses confirm that the network modeling method is feasible to some extent and especially useful for design of the connectors’arrangement,estimation of the connector loads and the related structural safety of a multi-module floating structure in early design stage.
基金supported by the Ministry of Industry and Information Technology(Grant Nos.[2016]22,[2019]357)the Ministry of Science and Technology(Grant No.2013CB36102)+1 种基金supported by the National KeyResearch and Development Program of China(Grant No.2017YFBO202701)the Jiangsu Province ScienceFoundation for Youths(BK20190151).
文摘Design of a very large floating structure(VLFS)deployed near islands and reefs,different from those in the open sea,inevitably faces new technical challenges including numerical analysis methods.In this paper,a direct coupling analysis method(DCAM)has been established based on the Boussinesq equations and the three-dimensional hydroelasisity theory with Rankine source method to analyze the responses of a VLFS in shallow sea with complicated geographical environment.Model tests have been carried out to validate the DCAM.To further verify the numerical methods and investigate the performance of such a VLFS,a“Scientific Research and Demonstration Platform(SRDP)”was built and deployed in 2019 at the site about 1000 m off an island with water depth around 40m in South China Sea.It is a simplified small model of a two-module semi-submersible-type VLFS.The numerical simulation of its responses on severe waves with focus on motions and connector forces is conduct by DCAM,and compared with the on-site measurements.Good agreement has been achieved.This approves the DCAM as a feasible tool for design and safety assessment of a VLFS deployed near islands and reefs.
基金supported by the National Key Research and Development Program of China(Grant No.2017YFB0202701)the Ministryof Industry and Information Technology(Grant Nos.[2016J22,[2019J357)+2 种基金supported by the State Key Fundamental Research Program(Grant No.2013CB036100)the Jiangsu Province Science Foundation for Youths(Grant No.BK20190151)the Fund of Southern Marine Science and Engineering Guangdong Laboratory(Zhanjiang)(Grant No.ZJW-2019-02).
文摘A mooring system has been designed for the position keeping of a two-module semi-submersible platform which is connected by hinge-type connectors.Under the excitation of ocean waves,the relative motion between the two modules can be significant.It is therefore no longer adequate to model the platform as a single rigid body in the analysis of the performance of the mooring system.In this study,an analysis method has been developed based on the three-dimensional frequency domain hydroelasticity theory in conjunction with the time domain quasi-static analysis method of mooring actions,which takes into account of the coupling effect of the platform motion and mooring tension.The proposed method is verified by comparing the numerical results with the measured data obtained from the on-site measurements.The comparison shows a good agreement,and demonstrates the feasibility and effectiveness of the proposed method for the analysis of the module responses and mooring tensions of multi-module floating platforms.
基金supported by Anhui Provincial Philosophy&Social Science Fund(AHSKY2023D12)Anqing Normal University Key Project Grant“Research on the Digital Interactive Development of Trade between China Railway Express and Countries along the Belt and Road Initiative”(SK202211ZD)。
文摘This paper focuses on how technology services can help small and medium-sized enterprises(SMEs)overcome the digital transformation dilemma of“cannot transform(lack of know-how),dare not transform(fear of risk),and have no money to transform(lack of funds).”Using literature analysis and multiple case comparisons,the study summarizes five major categories of technology services:technical support,consulting and planning,training and empowerment,resource integration,and financing connectivity.It constructs a“service–capability–performance”catalytic framework.Tracking of 58 enterprises in the Yangtze River Delta reveals that resource integration contributes the most to digital maturity,with absorptive capacity playing a significant mediating role;the configuration of“high technology services+high absorptive capacity+high environmental dynamism”is a sufficient condition for high transformation performance.Based on these findings,countermeasures are proposed,including improving the technology service system,strengthening government-industry-academia collaboration,and optimizing funding and talent supply,providing replicable experience for SMEs,governments,and technology service institutions.
基金supported by National Natural Science Foundation of China(81774304)Shaanxi Traditional Chinese Medicine Administration Research Project(SZYKJCYC-2025-JC-016)+1 种基金Qinchuangyuan Traditional Chinese Medicine Industrial Innovation Cluster Project(L2024-QCY-ZYYJJQ-X85)Xianyang Science and Technology Bureau Key R&D Program(L2022ZDYFSF003)。
文摘The potential application of Huangqi(Astragali Radix)in the treatment of diabetes mellitus(DM)has garnered increasing attention.β-cell dysfunction is one of the core mechanisms in the pathogenesis of DM and effectively protecting and restoring pancreaticβ-cell function remains a key challenge in DM prevention and treatment.Studies have shown that the active components of Huangqi(Astragali Radix)can alleviate glucolipotoxicity-inducedβ-cell damage by promoting glucose uptake mediated by glucose transporter 4(GLUT-4),inhibiting the Wnt1/β-catenin signaling pathway to reduce lipid deposition in liver and pancreatic tissues and upregulating peroxisome proliferator-activated receptorα(PPARα)gene expression.Additionally,Huangqi(Astragali Radix)can reduce cell apoptosis by mitigating endoplasmic reticulum stress,suppress pyroptosis via the NF-κB/NLRP3/TXNIP signaling pathway,and inhibit ferroptosis and autophagy to decreaseβ-cell death.Furthermore,Huangqi(Astragali Radix)can promoteβ-cell proliferation by modulating dedifferentiation and transdifferentiation,improve the islet microenvironment by regulating immune function and reducing M1 macrophage polarization,and may delayβ-cell senescence.This review summarizes the research progress of active ingredients in Huangqi(Astragali Radix)in protecting pancreaticβ-cell,which provides new insights and a scientific basis for its future application in DM prevention and treatment.
基金financially supported by the National Natural Science Foundation of China(Grant No.52001040),the Natural Science Foundation Project of Chongqing,Chongqing Science and Technology Commission(Grant No.cstc2021jcyj-msxmX0944)the Science and Technology Research Program of Chongqing Municipal Education Commission(Grant No.KJZD-K202300710).
文摘The influences of different factors,including whether the transverse frames are actually built,longitudinal and transverse welding residual stresses,and unloaded edge boundaries,on the ultimate strength and failure mode of a real hull bottom full-scale stiffened plate under axial compression and lateral pressure are investigated via numerical analysis.Result shows that the failure mode of the stiffened plate under axial compression is the tripping of the stiffeners.Whether transverse frames are built has little effect on the ultimate strength of the stiffened plate under axial compression,which can be replaced by the degree of freedom constraint.However,when lateral pressure is present,the transverse frame cannot be simply replaced by a free-degree constraint.The longitudinal residual stress has a greater effect on the ultimate strength,whereas the effect of the transverse residual stress is smaller.Stronger unloaded edge boundary conditions can slightly enhance the stiffness and ultimate strength of the stiffened plate.Under combined axial compression and lateral pressure,the failure mode of stiffened plates changes from the tripping of stiffeners to beam-column failure,as the lateral pressure increases.The ability of stiffened plates in which transverse frames are actually built out to resist beam-column shape deformation becomes weaker with lower ultimate strength.Stronger unloaded edge boundary conditions can improve the ability of stiffened plates to resist beam-column deformation and increase the ultimate strength.
基金financially supported by the Open Project Program of Shandong Marine Aerospace Equipment Technological Innovation Center,Ludong University(Grant Nos.MAETIC202209 and MAETIC202201)Shandong Provincial Natural Science Foundation(Grant No.ZR2022QE092)+2 种基金China Postdoctoral Science Foundation(Grant No.2023M730829)Open Fund of the State Key Laboratory of Industrial Equipment Structural Analysis(Grant No.GZ23109)the National Natural Science Foundation of China(Grant Nos.52001284 and 52192694).
文摘In the process of developing oil and gas resources in the Arctic,the impact of icebergs can pose a considerable threat to the structural safety of semi-submersible mooring platforms in ice regions.On the basis of the arbitrary Lagrangian Eulerian(ALE)algorithm,a numerical model for the interaction between an iceberg and a semi-submersible mooring platform is built in this work.First,a mooring system with a link element is designed and validated.An ice material model for the target iceberg is built and validated.A numerical model for the interaction between an iceberg and a semi-submersible mooring platform is then built.A parametric study(cable angle,tension angle and number of cables)is carried out to study the performance of the mooring system.The collision process between the semi-submersible mooring platform and the iceberg in the polar marine environment can be predicted by the present numerical model,and then the optimal mooring arrangement scheme can be obtained.The research results in this work can provide a reference for the design of mooring systems.
基金Funded by the Natural Science and Engineering Technology in Qinghai Province(2023)the Qinghai Province"Kunlun Talents"High End Innovation and Entrepreneurship Talent Project(2023)+4 种基金the Western Young Scholars Program of Chinese Academy of Sciences(2024,No.2022000018)the National Natural Science Foundation of China(N0.52404189)the Open Fund of Key Laboratory of Green and High-end Utilization of Salt Lake Resources(No.ISL2024-15)the Xining Major Science and Technology Innovation Platform Project(No.2024-Z-01)the Independent Deployment Project of the Qinghai Salt Lake Research Institute,CAS(No.E455HX3501)。
文摘In this essay,by summarizing the research progress and achievements of various scholars at home and abroad in recent years on the material properties and corrosion resistance of magnesium phosphate cement(MPC),we review the factors influencing on the properties of MPC,and analyze the effects of raw materials,retarders,and admixtures on the properties of MPC.Two different hydration mechanisms of MPC are discussed,and finally the research progress of MPC in the field of anti-corrosion coatings for steel and ordinary concrete(OPC)is highlighted,and suggestions and prospects are given.
基金National Council for Scientific and Technological Development,CNPq,Research Productivity,grant numbers:304747/2018-1/310135/2022-2(Reis LO).
文摘Objective:To determine the safety and the role of modulating cytokines and proteases in the immune response to intravesical Bacillus Calmette-Guérin(BCG)when primed with systemic intradermal BCG.Methods:Phase 1 and mechanistic longitudinal,prospective,single-blind randomized study(NCT04806178).Twenty-one non-muscle invasive urothelial bladder cancer patients undergoing intravesical adjuvant BCG after transurethral resection of bladder tumor(TURBT)in a teaching hospital between September 2021 and April 2023 were randomized to 0.1 mL of intradermal BCG vaccine or placebo(0.9%saline)administered 15 days before the start of intravesical BCG therapy.Blood samples were evaluated mechanistically regarding eight cytokines serum levels interferon-induced transmembrane protein 3 Gene(IFITM3),Interleukin 1 beta(IL1-BETA),interleukin-2 receptor alpha chain(IL2 RA),Interleukin 6(IL 6),Interleukin 10(IL 10),Tumor necrosis factor alpha(TNF-α),Interferon-β,AXL,and one protease CASPASE 8.Results:After 1 exclusion,twenty patients were randomized to intradermal BCG(n=11)and intradermal placebo(n=9).There was no difference in adverse effects emerging from the intravesical Onco-BCG therapy,and no difference in the expression of the cytokines and proteases analyzed between control and intervention,and over time.Conclusions:Intradermal BCG administration before intravesical application was safe,with no increase in adverse effects.It also does not seem to change the analyzed targets during the intravesical induction-phase BCG.Other immune targets should be explored in the future.The Brazilian tuberculosis-endemic status,where BCG vaccination is mandatory,might have affected the results.
基金supported by Yunnan Provincial Major Science and Technology Special Program(No.202402AA310035)Yunnan Key Laboratory of Dai and Yi Medicines(Yunnan University of Chinese Medicine)(No.2024JS2404)Research Foundation of Chuxiong Medical College(No.2024YYXM38).
文摘Background:Hua-Yi-Jie-Du formula(HYJD)is a traditional Chinese medicine that has proven effective against viral pneumonia and was extensively used during the COVID-19 pandemic.This study investigates how HYJD influences group 2 innate lymphoid cell(ILC2)and nucleotide oligomerization domain(NOD)-like receptor protein 3(NLRP3)inflammasome activation in a mouse model of viral pneumonia.Methods:A mouse model of viral pneumonia was established through the administration of polyinosinic-polycytidylic acid(poly(I:C))via nasal drops.Histopathological analysis of lung tissue was conducted,alongside enzyme-linked immunosorbent assay to quantify cytokine levels in serum and bronchoalveolar lavage fluid(BALF).Flow cytometry was employed to detect ILC2 cells in lung tissue and spleen,while immunofluorescence techniques were utilized to visualize ILC2 cells in lung tissue.Transcriptomic sequencing was performed,and the results were validated using qRT-PCR and western blot analysis.Results:HYJD significantly ameliorated inflammatory infiltration in lung tissue,decreased mucus protein secretion,and reduced the serum levels of inflammatory cytokines interleukin(IL)-1β,IL-6,and tumor necrosis factor-alpha(TNF-α).Additionally,it lowered the expression of cytokines IL-4,IL-5,IL-13,IL-25,thymic stromal lymphopoietin(TSLP),and IL-33 in BALF,and reduced the differentiation of ILC2 cells in both lung tissue and spleen.Transcriptomic analysis and experimental validation revealed that HYJD downregulated the expression of NLRP3 related genes and proteins within the NOD-like receptor signaling pathway.Conclusion:The mechanism by which HYJD intervenes in acute lung injury associated with viral pneumonia may involve the reduction of ILC2 cells differentiation and the inhibition of NLRP3 activation.
基金supported by the National Natural Science Foundation of China(No.52388102)the Sichuan Science and Technology Program(No.2024NSFTD0011)the Fundamental Research Funds for the State Key Laboratory of Rail Transit Vehicle System of Southwest Jiaotong University(No.2023TPL-T11).
文摘The dynamic characteristics of the track system can directly affect its service performance and failure process.To explore the load characteristics and dynamic response of the track system under the dynamic loads from the rack vehicle in traction conditions,a systematic test of the track subsystem was carried out on a large-slope test line.In the test,the bending stress of the rack teeth,the wheel-rail forces,and the acceleration of crucial components in the track system were measured.Subsequently,a detailed analysis was conducted on the tested signals of the rack railway track system in the time domain and the time-frequency domains.The test results indicate that the traction force significantly affects the rack tooth bending stress and the wheel-rail forces.The vibrations of the track system under the traction conditions are mainly caused by the impacts generated from the gear-rack engagement,which are then transferred to the sleepers,the rails,and the ballast beds.Furthermore,both the maximum stress on the racks and the wheel-rail forces measured on the rails remain below their allowable values.This experimental study evaluates the load characteristics and reveals the vibration characteristics of the rack railway track system under the vehicle’s ultimate load,which is very important for the load-strengthening design of the key components such as racks and the vibration and noise reduction of the track system.
基金supported by the National Natural Science Foundation of China(82071362 and 82270669)Key Project of the Regional Joint Fund of Guangdong Province(2023B1515120077)+3 种基金Basic Research Program of Shenzhen Science and Technology Innovation Commission(JCYJ20210324123001003 and JCYJ20220530144801003)Shenzhen Key Laboratory of Bone Tissue Repair and Translational Research(ZDSYS20230626091402006)the Innovation and Entrepreneurship Training Program for College Students,Sun Yat-sen University(20242150)the Leading Innovation and Entrepreneurship Team Program of Zhejiang Province,China(2023R01005).
文摘Activation of spinal cord neural stem cells(NSCs)and subsequent neurogenesis holds a promising alternative for spinal cord injury(SCI)repair.Our previous study demonstrated that complement C3a,derived from reactive astrocytes,inhibits NSC proliferation by suppressing protein aggregate clearance through the deubiquitinating enzyme ubiquitin carboxy-terminal hydrolase L1(UCHL1)-proteasome system post-SCI.However,the potential molecular mechanism by which C3a modulates NSC activation via this pathway remains unclear.Here,we revealed that C3a/C3a receptor(C3aR)signaling activated NF-κB p65,which in turn inhibited Nrf2 activity and UCHL1 expression,resulting in diminished proteasome activity and the accumulation of protein aggregates,and ultimately impaired NSC activation.Both knockdown of NF-κB p65 and Nrf2 upregulation restored UCHL1 expression and proteasome activity in vitro,promoting NSC activation by enhancing protein aggregate clearance.Mechanistically,we found that NF-κB p65 regulated Nrf2 activity through a dual mechanism:(1)promoting Keap1-dependent ubiquitination and proteasome degradation of Nrf2;(2)inhibiting protein kinase C-mediated Nrf2 phosphorylation and nuclear translocation.Using the dual-luciferase reporter assay and chromatin immunoprecipitation(ChIP)analysis,we further identified UCHL1 as a direct transcriptional target of Nrf2.Importantly,in vivo experiments using SCI mice confirmed that either C3aR blockade,NF-κB p65 knockdown,or Nrf2 overexpression could rescue SCI-induced UCHL1 downregulation.Together,this study uncovers the C3a-NF-κB p65-Nrf2-UCHL1-proteasome axis as a critical regulator of NSC activation after SCI.This may provide novel molecular targets and intervention strategies for SCI repair.
基金Supported by the Sichuan Science and Technology Program(Grant Nos.2021YFD0211,2023ZDZX0011).
文摘Significant diurnal temperature variations in mountainous rack railways cause stiffness mismatches between the rack structure and simply supported bridges,leading to critical failures like bolt loosening and rack fractures.This study develops a dynamic model of the vehicle-rack-bridge system based on train-track-bridge interaction theory,integrating gear-rack meshing and wheel-rail contact mechanisms.The model analyzes the dynamic response of bridges with varying spans under combined thermal and dynamic loading.Numerical simulations,conducted using finite element analysis,reveal peak vibration accelerations of 1.3 m/s^(2)for the rack,3.0 m/s^(2)for the rail,1.2 m/s^(2)for the sleeper,and 0.1 m/s^(2)for the bridge,with maximum stresses of 3 MPa in the rack,8 MPa in the rail,and 25 MPa in connecting bolts.The results show significant span-dependent amplification of stress and strain in the rack system under thermo-mechanical loading,exceeding material strength limits at 60-meter spans.An innovative elastic connection method is proposed to mitigate stress concentrations effectively,en-hancing system durability.This study introduces a novel approach to modeling complex thermo-mechanical interactions in rack railway systems,validated through extensive simulations,and provides a practical solution for improving structural resilience,offering theoretical guidance for optimizing rack-bridge system design to ensure operational safety in extreme environmental conditions.
基金supported in part by the National Natural Science Foundation of China under Grants 62473176,62073155,62002137,62106088,and 62206113National Key Laboratory of Ship Structural Safety underGrant 450324300the Postgraduate Research&Practice Innovation Programof Jiangsu Province under Grant KYCX24_2642.
文摘Community detection is a fundamental problem in network analysis for identifying densely connected node clusters,with successful applications in diverse fields like social networks,recommendation systems,biology,and cyberattack detection.Overlapping community detection refers to the case of a node belonging to multiple communities simultaneously,which is a much more meaningful and challenging task.Graph representation learning with Evolutionary Computation has been studied well in overlapping community detection to deal with complex network structures and characteristics.However,most of them focus on searching the entire solution space,which can be inefficient and lead to inadequate results.To overcome the problem,a structural feature node extraction method is first proposed that can effectively map a network into a structural embedding space.Thus,nodes within the network are classified into hierarchical levels based on their structural feature strength,and only nodes with relatively high strength are considered in subsequent search steps to reduce the search space.Then,a maximal-clique representation method is employed on the given vertex set to identify overlapping nodes.A hybrid clique-based multi-objective evolutionary algorithmwith decomposition method is designed to address cliques and the remaining unexplored nodes separately.The number of communities generated with this allocation method is closer to the actual partition count with high division quality.Experimental results on nine usually used real-world networks,five synthetic networks,and two large-scale networks demonstrate the effectiveness of the proposed methodology in terms of community quality and algorithmic efficiency,compared to traditional,MOEA-based,and graph embedding-based community detection algorithms.
基金supported by the National Key R&D Program of China(Grant No.2023YFC3209504)Natural Science Foundation of Wuhan(Grant No.2024040801020271)the Fundamental Research Funds for Central Public Welfare Research Institutes(Grant No.CKSF2025718/YT).
文摘Wetting deformation in earth-rockfill dams is a critical factor influencingdam safety.Although numerous mathematical models have been developed to describe this phenomenon,most of them rely on empirical formulations and lack prior knowledge of model parameters,which is essential for Bayesian parameter inversion to enhance accuracy and reduce uncertainty.This study introduces a datadriven approach to establishing prior knowledge of earth-rockfill dams.Driving factors are utilized to determine the potential range of model parameters,and settlement changes within this range are calculated.The results are iteratively compared with actual monitoring data until the calculated range encompasses the observed data,thereby providing prior knowledge of the model parameters.The proposed method is applied to the right-bank earth-rockfilldam of Danjiangkou.Employing a Gibbs sample size of 30,000,the proposed method effectively calibrates the prior knowledge of the wetting model parameters,achieving a root mean square error(RMSE)of 5.18 mm for the settlement predictions.By comparison,the use of non-informative priors with sample sizes of 30,000 and 50,000 results in significantly larger RMSE values of 11.97 mm and 16.07 mm,respectively.Furthermore,the computational efficiencyof the proposed method is demonstrated by an inversion computation time of 902 s for 30,000 samples,which is notably shorter than the 1026 s and 1558 s required for noninformative priors with 30,000 and 50,000 samples,respectively.These findingsunderscore the superior performance of the proposed approach in terms of both prediction accuracy and computational efficiency.These results demonstrate that the proposed method not only improves the predictive accuracy but also enhances the computational efficiency,enabling optimal parameter identificationwith reduced computational effort.This approach provides a robust and efficientframework for advancing dam safety assessments.
文摘AIM:To compare the tear film quantity and stability parameters in keratoconus(KCN)and normal eyes using test breakup time(TBUT),noninvasive TBUT(NITBUT),and Schirmer test.METHODS:All participants(n=166),including patients with KCN and age-matched healthy individuals with normal corneas,were recruited from those referred to Farabi Eye Hospital,Iran,in 2023.To better account for genetic and environmental factors,the control group comprised healthy individuals who were relatives of KCN patients and had normal corneal topography.Tear quantity parameters were evaluated in the following order:NITBUT,TBUT,and Schirmer tests.RESULTS:The mean age of cases in KCN(61.7%males)and normal(63.5%males)participants was 27.54±5.44y(range 19 to 38)and 27.52±5.63y(range 20 to 38),respectively(P=0.976).NIBUT,TBUT,and Schirmer’s tests were significantly lower in KCN group compared to normal controls(all P<0.001).The mean difference for NIBUT was-7.81s(P<0.001),and for TBUT was-7.61s(P<0.001).Schirmer test values were also significantly lower in the KCN group,with a mean difference of-5.61 mm compared to normal people(P<0.001).CONCLUSION:Our findings demonstrate significant tear film impairment in KCN.The reductions in NIBUT,TBUT and Schirmer scores highlight an underlying tear film dysfunction in KCN that extends beyond the morphological changes of the cornea.
基金Funded by the National Key R&D Program of China(No.2023YFC3806100)the National Nature Science Foundation of China(Nos.52278269,52278268,52178264,and 52108238)+2 种基金the Tianjin Outstanding Young Scholars Science Fund Project(No.22JCJQJC00020)the Key Project of Tianjin Natural Science Foundation(No.23JCZDJC00430)the Joint Research Center of China and Foreign Countries Special Fund of Tianjin Innovation Platform(No.24PTLYHZ00240)。
文摘Sporosarcina pasteurii was employed as the strain,with an in-situ magnetization construction,to obtain magnetic microorganisms and oriented self-healing mortar specimens based on them.The magnetic field was used to achieve the directional migration of magnetic microorganisms during the oriented selfhealing of mortar cracks,improving the rate of self-healing of cracks.The experimental results demonstrate that the magnetic microorganisms are composed of Fe_(3)O_(4)nanosheets attached to the surface of Sporosarcina pasteurii,whose mineralization products are comprised of vaterite primarily.Compared with the pure microbial group,the magnetic microbial group exhibits a faster repair rate,shortening the repair time required to achieve an area repair efficiency of over 90%from 28 days to 14 days,thereby doubling the repair rate.Meanwhile,the area repair efficiency of the magnetic microbial group at 7,14,and 28 days are increased by 50.3%,11.2%,and 4.6%,respectively,compared to the pure microbial group,which are due to the magnetic microorganisms'superior directional migration and mineralization ability,exceeding that of the ordinary microorganisms.
文摘The newly formulated non-Newtonian rivulet flows streaming down an inclined planar surface,with additional periodic perturbations arising from the application of the 2nd Stokes problem to the investigation of rivulet dynamics,are demonstrated in the current research.Hereby,the 2nd Stokes problem assumes that the surface,with a thin shared layer of the fluid on it,oscillates in a harmonic manner along the x-axis of the rivulet flow,which coincides with the main flow direction streaming down the underlying surface.We obtain the exact extension of the rivulet flow family,clarifying the structure of the pressure field,which fully absorbs the arising perturbation.The profile of the velocity field is assumed to be Gaussian-type with a non-zero level of plasticity.Hence,the absolutely non-Newtonian case of the viscoplastic flow solution,which satisfies the motion and continuity equations,is considered(with particular cases of exact solutions for pressure).The perturbed governing equations of motion for rivulet flows then result in the Riccati-type ordinary differential equation(ODE),describing the dynamics of the coordinate x(t).The approximated schematic dynamics are presented in graphical plots.
基金the Scientific Research Projects Unit of Erciyes University under contract no:FDS-2022-11532 and FOA-2025-14773.
文摘This paper examines a model that combines vortex generators and leading-edge tubercles for controlling the laminar separation bubble(LSB)over an airfoil at low Reynolds numbers(Re).This new concept of passive flow control technique utilizing a tubercle and vortex generator(VG)close to the leading edge was analyzed numerically for a NACA0015 airfoil.In this study,the Shear Stress Transport(SST)turbulence model was employed in the numerical modelling.Numerical modelling was completed using the ANSYS-Fluent 18.2 solver.Analyses were conducted to investigate the flow pattern and understand the underlying LSB control phenomena that enabled the new passive flow control method to provide this significant performance benefit.The findings indicated that the new concept of passive flow control technique suppressed the formation of an LSB at the suction surface of the NACA0015 airfoil,resulting in a higher lift coefficient and improved aerodynamic performance.Improvements in LSB dynamics and aerodynamic performance through the passive flow control method lead to increased energy output and enhanced stability.
