Sloshing experiment is crucial to determine the reaction performance of regeneration columns on an offshore floating platform.A novel type of column motion simulating device and a Marine Predator Algorithm-based Slidi...Sloshing experiment is crucial to determine the reaction performance of regeneration columns on an offshore floating platform.A novel type of column motion simulating device and a Marine Predator Algorithm-based Sliding Mode Controller(MPA-SMC)are proposed for such sloshing experiments.The simulator consists of a Stewart platform and a steel framework.The Stewart platform is located at the column's center of gravity(CoG)and supported by the steel framework.The platform's hydraulic servo system is controlled by a sliding mode controller with parameters optimized by MPA to improve robustness and precision.A numerical sloshing experiment is conducted using the proposed device and controller.The results show that the novel motion simulator has lower torque during the column sloshes,and the proposed controller performs better than a well-tuned PID controller in terms of target tracking precision and anti-interference capability.展开更多
Correction:J Cotton Res 8,27(2025)https://doi.org/10.1186/s42397-025-00228-y During the publication process of the original article(Soltani Toularoud et al.2025),the article title has been wrongly captured.Te article ...Correction:J Cotton Res 8,27(2025)https://doi.org/10.1186/s42397-025-00228-y During the publication process of the original article(Soltani Toularoud et al.2025),the article title has been wrongly captured.Te article title should be corrected from:of butisanstar and clopyralid herbicides on Gos-sypium hirsutum L.growth:insights from a pot experiment to:Residual efects of butisanstar and clopyralid herbi-cides on Gossypium hirsutum L.growth:insights from a pot experiment Te original article(Soltani Toularoud et al.2025)has been updated.Te publisher apologizes to the authors and readers for the inconvenience caused.展开更多
Multiple quadrotors target encirclement is widely used in the intelligent field,as it can effectively monitor and control target behavior.However,it faces the danger of collision,as well as difficulties in localizatio...Multiple quadrotors target encirclement is widely used in the intelligent field,as it can effectively monitor and control target behavior.However,it faces the danger of collision,as well as difficulties in localization and tracking.Therefore,we propose a complete target encirclement method.Firstly,based on Hooke's law,a collision avoidance controller is designed to maintain a safe flying distance among quadrotors.Then,based on the consensus theory,a formation tracking controller is designed to meet the requirements of formation transformation and encirclement tasks,and a stability proof based on Lyapunov was provided.Besides,the target detection is designed based on YOLOv5s,and the target location model is constructed based on the principle of pinhole projection and triangle similarity.Finally,we conducted experiments on the built platform,with 3 reconnaissance quadrotors detecting and localization 3 target vehicles and 7 hunter quadrotors tracking them.The results show that the minimum average error for localization targets with reconnaissance quadrotors can reach 0.1354 m,while the minimum average error for tracking with hunter quadrotors is only 0.2960 m.No quadrotors collision occurred in the whole formation transformation and tracking experiment.In addition,compared with the advanced methods,the proposed method has better performance.展开更多
Reusable and flexible capturing of space debris is highly required in future aerospace technologies.A tendon-actuated flexible robotic arm is therefore proposed for capturing floating targets in this paper.Firstly,an ...Reusable and flexible capturing of space debris is highly required in future aerospace technologies.A tendon-actuated flexible robotic arm is therefore proposed for capturing floating targets in this paper.Firstly,an accurate dynamic model of the flexible robotic arm is established by using the absolute nodal coordinate formulation(ANCF)in the framework of the arbitrary Lagrangian-Eulerian(ALE)description and the natural coordinate formulation(NCF).The contact and self-contact dynamics of the flexible robotic arm when bending and grasping an object are considered via a fast contact detection approach.Then,the dynamic simulations of the flexible robotic arm for capturing floating targets are carried out to study the influence of the position,size,and mass of the target object on the grasping performance.Finally,a principle prototype of the tendon-actuated flexible robotic arm is manufactured to validate the dynamic model.The corresponding grasping experiments for objects of various shapes are also conducted to illustrate the excellent performance of the flexible robotic arm.展开更多
This study focuses on the thermal management of 4680-type cylindrical lithium-ion battery packs utilizing NCM811 chemistry.It establishes coupled multi-physics models for both immersion and serpentine cold plate cooli...This study focuses on the thermal management of 4680-type cylindrical lithium-ion battery packs utilizing NCM811 chemistry.It establishes coupled multi-physics models for both immersion and serpentine cold plate cooling systems.Through a combination of numerical simulation and experimental validation,the technical advantages and mechanisms of immersion cooling are systematically explored.Simulation results indicate that under a 3C fast-charging condition(inlet temperature 20℃,flow rate 36 L/min),the immersion cooling structure 3demonstrates a triple enhancement in thermal performance compared to the cold plate structure 1:a 13.06%reduction in peak temperature,a 31.67%decrease in overall maximum temperature difference,and a 47.62%decrease in single-cell temperature deviation,while also reducing flow resistance by 33.61%.Furthermore,based on the immersion cooling model,a small battery module comprising seven cylindrical cells was designed for thermal runaway testing via nail penetration.The results show that the peak temperature of the triggered cell was limited to 437.6℃,with a controllable temperature rise gradient of only 3.35℃/s and a rapid cooling rate of 0.6℃/s.The maximum temperature rise of adjacent cells was just 64.8℃,effectively inhibiting thermal propagation.Post-test disassembly revealed that the non-triggered cells retained>99.2%of their original voltage and>99%structural integrity,confirming the module’s ability to achieve“localized failure with global stability.”展开更多
Objective Traditional Chinese medicine(TCM)constitutes a valuable cultural heritage and an important source of antitumor compounds.Poria(Poria cocos(Schw.)Wolf),the dried sclerotium of a polyporaceae fungus,was first ...Objective Traditional Chinese medicine(TCM)constitutes a valuable cultural heritage and an important source of antitumor compounds.Poria(Poria cocos(Schw.)Wolf),the dried sclerotium of a polyporaceae fungus,was first documented in Shennong’s Classic of Materia Medica and has been used therapeutically and dietarily in China for millennia.Traditionally recognized for its diuretic,spleen-tonifying,and sedative properties,modern pharmacological studies confirm that Poria exhibits antioxidant,anti-inflammatory,antibacterial,and antitumor activities.Pachymic acid(PA;a triterpenoid with the chemical structure 3β-acetyloxy-16α-hydroxy-lanosta-8,24(31)-dien-21-oic acid),isolated from Poria,is a principal bioactive constituent.Emerging evidence indicates PA exerts antitumor effects through multiple mechanisms,though these remain incompletely characterized.Neuroblastoma(NB),a highly malignant pediatric extracranial solid tumor accounting for 15%of childhood cancer deaths,urgently requires safer therapeutics due to the limitations of current treatments.Although PA shows multi-mechanistic antitumor potential,its efficacy against NB remains uncharacterized.This study systematically investigated the potential molecular targets and mechanisms underlying the anti-NB effects of PA by integrating network pharmacology-based target prediction with experimental validation of multi-target interactions through molecular docking,dynamic simulations,and in vitro assays,aimed to establish a novel perspective on PA’s antitumor activity and explore its potential clinical implications for NB treatment by integrating computational predictions with biological assays.Methods This study employed network pharmacology to identify potential targets of PA in NB,followed by validation using molecular docking,molecular dynamics(MD)simulations,MM/PBSA free energy analysis,RT-qPCR and Western blot experiments.Network pharmacology analysis included target screening via TCMSP,GeneCards,DisGeNET,SwissTargetPrediction,SuperPred,and PharmMapper.Subsequently,potential targets were predicted by intersecting the results from these databases via Venn analysis.Following target prediction,topological analysis was performed to identify key targets using Cytoscape software.Molecular docking was conducted using AutoDock Vina,with the binding pocket defined based on crystal structures.MD simulations were performed for 100 ns using GROMACS,and RMSD,RMSF,SASA,and hydrogen bonding dynamics were analyzed.MM/PBSA calculations were carried out to estimate the binding free energy of each protein-ligand complex.In vitro validation included RT-qPCR and Western blot,with GAPDH used as an internal control.Results The CCK-8 assay demonstrated a concentration-dependent inhibitory effect of PA on NB cell viability.GO analysis suggested that the anti-NB activity of PA might involve cellular response to chemical stress,vesicle lumen,and protein tyrosine kinase activity.KEGG pathway enrichment analysis suggested that the anti-NB activity of PA might involve the PI3K/AKT,MAPK,and Ras signaling pathways.Molecular docking and MD simulations revealed stable binding interactions between PA and the core target proteins AKT1,EGFR,SRC,and HSP90AA1.RT-qPCR and Western blot analyses further confirmed that PA treatment significantly decreased the mRNA and protein expression of AKT1,EGFR,and SRC while increasing the HSP90AA1 mRNA and protein levels.Conclusion It was suggested that PA may exert its anti-NB effects by inhibiting AKT1,EGFR,and SRC expression,potentially modulating the PI3K/AKT signaling pathway.These findings provide crucial evidence supporting PA’s development as a therapeutic candidate for NB.展开更多
Equipment systems-of-systems （SOS） effectiveness evaluation can provide important reference for construction and optimization of the equipment SoS. After discussing the basic theory and methods of parallel experimen...Equipment systems-of-systems （SOS） effectiveness evaluation can provide important reference for construction and optimization of the equipment SoS. After discussing the basic theory and methods of parallel experiments, we depict an SoS effectiveness analysis and evaluation method using parallel expe- riments theory in detail. A case study is carried out which takes the missile defense system as an example. An artificial system of the missile defense system is constructed with the multi-agent modeling method. Then, single factor, multiple factors and defense position deployment computational experiments are carried out and evaluated with the statistical analysis method. Experiment re- sults show that the altitude of the secondary interception missile is not the key factor which affects SoS effectiveness and putting the defense position ahead will increase defense effectiveness. The case study demonstrates the feasibility of the proposed method.展开更多
Soft rock control is a big challenge in underground engineering.As for this problem,a high-strength support technique of confined concrete(CC)arches is proposed and studied in this paper.Based on full-scale mechanical...Soft rock control is a big challenge in underground engineering.As for this problem,a high-strength support technique of confined concrete(CC)arches is proposed and studied in this paper.Based on full-scale mechanical test system of arch,research is made on the failure mechanism and mechanical properties of CC arch.Then,a mechanical calculation model of circular section is established for the arches with arbitrary section and unequal rigidity;a calculation formula is deduced for the internal force of the arch;an analysis is made on the influence of different factors on the internal force of the arch;and a calculation formula is got for the bearing capacity of CC arch through the strength criterion of bearing capacity.With numerical calculation and laboratory experiment,the ultimate bearing capacity and internal force distribution is analyzed for CC arches.The research results show that:1)CC arch is 2.31 times higher in strength than the U-shaped steel arch and has better stability;2)The key damage position of the arch is the two sides;3)Theoretical analysis,numerical calculation and laboratory experiment have good consistency in the internal force distribution,bearing capacity,and deformation and failure modes of the arch.All of that verifies the correctness of the theoretical calculation.Based on the above results,a field experiment is carried out in Liangjia Mine.Compared with the U-shaped steel arch support,CC arch support is more effective in surrounding rock deformation control.The research results can provide a basis for the design of CC arch support in underground engineering.展开更多
A mobile robot developed by Wuhan University for full-path hotline inspection on 220 kV transmission lines was presented. With 4 rotating joints and 2 translational ones, such robot is capable of traveling along non- ...A mobile robot developed by Wuhan University for full-path hotline inspection on 220 kV transmission lines was presented. With 4 rotating joints and 2 translational ones, such robot is capable of traveling along non- obstaclestraight-line segment and surmounting straight-line segment obstacles as well as transferring between two spans automatically. Lagrange’s equations were utilized to derive dynamic equations of all the links, including items of inertia, coupling inertia, Coriolis acceleration, centripetal acceleration and gravity. And a dynamic response experiment on elemental motions of robot prototype’s travelling along non-obstacle straight-line segment and surmounting obstacles was performed on 220 kV 1∶1 simulative overhanging transmission-line in laboratory. In addition, dynamic numerical simulation was conducted in the corresponding condition. Comparison and analysis on results of experiment and numerical simulation have validated theoretical model and simulation resolution. Therefore, the dynamic model formed hereunder can be used for the study of robot control.展开更多
Vegetation plays a key role in improving wind environment of residential districts,and is helpful for creating a comfortable and beautiful living environment.The optimal design of vegetation for wind environment impro...Vegetation plays a key role in improving wind environment of residential districts,and is helpful for creating a comfortable and beautiful living environment.The optimal design of vegetation for wind environment improvement in winter was investigated by carrying out field experiments in Heqingyuan residential area in Beijing,and after that,numerical simulation with SPOTE(simulation platform for outdoor thermal environment) experiments for outdoor thermal environment of vegetation was adopted for comparison.The conclusions were summarized as follows:1) By comparing the experimental data with simulation results,it could be concluded that the wind field simulated was consistent with the actual wind field,and the flow distribution impacted by vegetation could be accurately reflected;2) The wind velocity with vegetation was lower than that without vegetation,and the wind velocity was reduced by 46%;3) By adjusting arrangement and types of vegetation in the regions with excessively large wind velocity,the pedestrian-level wind velocity could be obviously improved through the simulation and comparison.展开更多
Flight simulator is an important device and a typical high-performance position and speed servo system used in the hardware-in-the-loop simulation of flight control system. Friction is the main nonlinear resistance in...Flight simulator is an important device and a typical high-performance position and speed servo system used in the hardware-in-the-loop simulation of flight control system. Friction is the main nonlinear resistance in the flight simulator servo system, especially in a low-speed state. Based on the description of dynamic and static models of a nonlinear Stribeck friction model, this paper puts forward sliding mode controller to overcome the friction, whose stability is展开更多
Time synchronization is a critical middleware service of wireless sensor networks. Researchers have already proposed some time synchronization algorithms. However, due to the demands for various synchronization precis...Time synchronization is a critical middleware service of wireless sensor networks. Researchers have already proposed some time synchronization algorithms. However, due to the demands for various synchronization precision, existing time synchronization algorithms often need to be adapted. So it is necessary to evaluate these adapted algorithms before use. Software simulation is a valid and quick way to do it. In this paper, we present a time synchronization simulator, Simsync, for wireless sensor networks. We decompose the packet delay into 6 delay components and model them separately. The frequency of crystal oscillator is modeled as Gaussian. To testify its effectiveness, we simulate the reference broadcast synchronization algorithm (RBS) and the timing-sync synchronization algorithm (TPSN) on Simsync. Simulated results are also presented and analyzed.展开更多
The viscoelastic-plastic creep experiments on soft ore-rock in Jinchuan Mine III were performed under circular increment step load and unload. The experimental data were analyzed according to instantaneous elastic str...The viscoelastic-plastic creep experiments on soft ore-rock in Jinchuan Mine III were performed under circular increment step load and unload. The experimental data were analyzed according to instantaneous elastic strain, visco-elastic strain, instantaneous plastic strain and visco-plastic strain. The result shows that instantaneous deformation modulus tends to increase with the increase of creep stress; soft rocks enhance the ability to resist instantaneous elastic deformation and instantaneous plastic deformation during the multi-level of load and unload in the cyclic process. In respect of specimen JC1099, the ratio of visco-elastic strain to visco-plastic strain varies from 3.15 to 6.58, and the ratio has decreasing tendency with stress increase as a whole; creep deformation tends to be a steady state at low stress level; soft rocks creep usually embodies accelerated creep properties at high stress level. With the damaging variable and the hardening function introduced, a nonlinear creep model of soft rocks is established, in which the decay creep is described by the nonlinear hardening function H of viscidity coefficient. The model can describe the accelerated creep of soft rocks since the nonlinear damaging evolvement variable D of deformation parameter of rocks is introduced. Three stages of soft rocks creep can be described with the uniform creep equation in the nonlinear creep model. With this nonlinear creep model applied to the creep experiments of the ore-rock of Jinchuan Mine III, the nonlinear creep model＇s curves are in good agreement with experimental data.展开更多
As friction, intrinsic steady-state nonlinearity poses a challenging dilemma to the control system of 3-DOF （three degree of freedom） flight simulator, a novel hybrid control strategy of nonlinear PID （proportional...As friction, intrinsic steady-state nonlinearity poses a challenging dilemma to the control system of 3-DOF （three degree of freedom） flight simulator, a novel hybrid control strategy of nonlinear PID （proportionalintegral-derivative） with additional FFC （feed-forward controller） is proposed, and the hardware-in-the-loop simulation results are also given. Based on the description of 3-DOF flight simulator, a novel nonlinear PID theory is well introduced. Then a nonlinear PID controller with additional FFC is designed. Subsequently, the loop structure of 3-DOF flight simulator is also designed. Finally, a series of hardware-in-the-loop simulation experiments are undertaken to verify the feasibility and effectiveness of the proposed nonlinear PID controller with additional FFC for 3-DOF flight simulator.展开更多
To determine the ultimate bearing capacity of foundations on sloping ground surface in practice, energy dissipation method was used to formulate the beating capacity as programming problem, and full-scale model experi...To determine the ultimate bearing capacity of foundations on sloping ground surface in practice, energy dissipation method was used to formulate the beating capacity as programming problem, and full-scale model experiments were investigated to analyze the performance of the soil slopes loaded by a strip footing in laboratory. The soil failure is governed by a linear Mohr-Coulomb yield criterion, and soil deformation follows an associated flow rule. Based on the energy dissipation method of plastic mechanics, a multi-wedge translational failure mechanism was employed to obtain the three bearing capacity factors related to cohesion, equivalent surcharge load and the unit gravity for various slope inclination angles. Numerical results were compared with those of the published solutions using finite element method and those of model experiments. The bearing capacity factors were presented in the form of design charts for practical use in engineering. The results show that limit analysis solutions approximate to those of model tests, and that the energy dissipation method is effective to estimate bearing capacity of soil slope.展开更多
To improve the robustness of high-precision servo systems, quantitative feedback theory （QFT） which aims to achieve a desired robust design over a specified region of plant uncertainty is proposed. The robust design...To improve the robustness of high-precision servo systems, quantitative feedback theory （QFT） which aims to achieve a desired robust design over a specified region of plant uncertainty is proposed. The robust design problem can be solved using QFT but it fails to guarantee a high precision tracking. This problem is solved by a robust digital QFT control scheme based on zero phase error （ZPE） feed forward compensation. This scheme consists of two parts： a QFT controller in the closed-loop system and a ZPE feed-forward compensator. Digital QFT controller is designed to overcome the uncertainties in the system. Digital ZPE feed forward controller is used to improve the tracking precision. Simulation and real-time examples for flight simulator servo system indicate that this control scheme can guarantee both high robust performance and high position tracking precision.展开更多
In order to solve the problems which are widespread in potato seeding planter, such as lower operating efficiency, unideal performance index, higher replay rate and leakage rate and uneven spacing sowing in seeding op...In order to solve the problems which are widespread in potato seeding planter, such as lower operating efficiency, unideal performance index, higher replay rate and leakage rate and uneven spacing sowing in seeding operating, a trailed potato fertilization seeder was designed. The key components of the special structure had been got through the description of the structure and working principle of the whole machine. A crossing seed-taken technology along with the vibration component was adopted to achieve precision seeding. The results showed in the feld test of the machine： all the performance indexes of the machine met the agronomic requirement of potato planting; the multiple and missing index were low; it completed the ditching, fertilizing, seeding as well as ridging in one planting process; its operation effciency was high and the stability was good. This design of the trailed potato fertilization seeder provided a reference for the development of large traction-type potato seeding machine.展开更多
In order to improve and enhance the numerical modeling methods and its application on debris flow problems,a preliminary study has been proposed in accordance with the corrected water-sediment numerical model on the p...In order to improve and enhance the numerical modeling methods and its application on debris flow problems,a preliminary study has been proposed in accordance with the corrected water-sediment numerical model on the premise of revised resistance and sediment capacity equations.Firstly,an overview the recent re- search achievements on numerical simulation of debris flow has been conducted,the results shown that a gener- al numerical model for debris flow can not be existed at all because the complex rheol...展开更多
文摘Sloshing experiment is crucial to determine the reaction performance of regeneration columns on an offshore floating platform.A novel type of column motion simulating device and a Marine Predator Algorithm-based Sliding Mode Controller(MPA-SMC)are proposed for such sloshing experiments.The simulator consists of a Stewart platform and a steel framework.The Stewart platform is located at the column's center of gravity(CoG)and supported by the steel framework.The platform's hydraulic servo system is controlled by a sliding mode controller with parameters optimized by MPA to improve robustness and precision.A numerical sloshing experiment is conducted using the proposed device and controller.The results show that the novel motion simulator has lower torque during the column sloshes,and the proposed controller performs better than a well-tuned PID controller in terms of target tracking precision and anti-interference capability.
文摘Correction:J Cotton Res 8,27(2025)https://doi.org/10.1186/s42397-025-00228-y During the publication process of the original article(Soltani Toularoud et al.2025),the article title has been wrongly captured.Te article title should be corrected from:of butisanstar and clopyralid herbicides on Gos-sypium hirsutum L.growth:insights from a pot experiment to:Residual efects of butisanstar and clopyralid herbi-cides on Gossypium hirsutum L.growth:insights from a pot experiment Te original article(Soltani Toularoud et al.2025)has been updated.Te publisher apologizes to the authors and readers for the inconvenience caused.
基金the National Natural Science Foundation of China(Grant Nos.62303348 and 62173242)the Aeronautical Science Foundation of China(Grant No.2024M071048002)the National Science Fund for Distinguished Young Scholars(Grant No.62225308)to provide fund for conducting experiments.
文摘Multiple quadrotors target encirclement is widely used in the intelligent field,as it can effectively monitor and control target behavior.However,it faces the danger of collision,as well as difficulties in localization and tracking.Therefore,we propose a complete target encirclement method.Firstly,based on Hooke's law,a collision avoidance controller is designed to maintain a safe flying distance among quadrotors.Then,based on the consensus theory,a formation tracking controller is designed to meet the requirements of formation transformation and encirclement tasks,and a stability proof based on Lyapunov was provided.Besides,the target detection is designed based on YOLOv5s,and the target location model is constructed based on the principle of pinhole projection and triangle similarity.Finally,we conducted experiments on the built platform,with 3 reconnaissance quadrotors detecting and localization 3 target vehicles and 7 hunter quadrotors tracking them.The results show that the minimum average error for localization targets with reconnaissance quadrotors can reach 0.1354 m,while the minimum average error for tracking with hunter quadrotors is only 0.2960 m.No quadrotors collision occurred in the whole formation transformation and tracking experiment.In addition,compared with the advanced methods,the proposed method has better performance.
基金funded by the"14th Five-Year Plan"Civil Aerospace Pre-research Project of China(Grant No.D010301).
文摘Reusable and flexible capturing of space debris is highly required in future aerospace technologies.A tendon-actuated flexible robotic arm is therefore proposed for capturing floating targets in this paper.Firstly,an accurate dynamic model of the flexible robotic arm is established by using the absolute nodal coordinate formulation(ANCF)in the framework of the arbitrary Lagrangian-Eulerian(ALE)description and the natural coordinate formulation(NCF).The contact and self-contact dynamics of the flexible robotic arm when bending and grasping an object are considered via a fast contact detection approach.Then,the dynamic simulations of the flexible robotic arm for capturing floating targets are carried out to study the influence of the position,size,and mass of the target object on the grasping performance.Finally,a principle prototype of the tendon-actuated flexible robotic arm is manufactured to validate the dynamic model.The corresponding grasping experiments for objects of various shapes are also conducted to illustrate the excellent performance of the flexible robotic arm.
文摘This study focuses on the thermal management of 4680-type cylindrical lithium-ion battery packs utilizing NCM811 chemistry.It establishes coupled multi-physics models for both immersion and serpentine cold plate cooling systems.Through a combination of numerical simulation and experimental validation,the technical advantages and mechanisms of immersion cooling are systematically explored.Simulation results indicate that under a 3C fast-charging condition(inlet temperature 20℃,flow rate 36 L/min),the immersion cooling structure 3demonstrates a triple enhancement in thermal performance compared to the cold plate structure 1:a 13.06%reduction in peak temperature,a 31.67%decrease in overall maximum temperature difference,and a 47.62%decrease in single-cell temperature deviation,while also reducing flow resistance by 33.61%.Furthermore,based on the immersion cooling model,a small battery module comprising seven cylindrical cells was designed for thermal runaway testing via nail penetration.The results show that the peak temperature of the triggered cell was limited to 437.6℃,with a controllable temperature rise gradient of only 3.35℃/s and a rapid cooling rate of 0.6℃/s.The maximum temperature rise of adjacent cells was just 64.8℃,effectively inhibiting thermal propagation.Post-test disassembly revealed that the non-triggered cells retained>99.2%of their original voltage and>99%structural integrity,confirming the module’s ability to achieve“localized failure with global stability.”
文摘Objective Traditional Chinese medicine(TCM)constitutes a valuable cultural heritage and an important source of antitumor compounds.Poria(Poria cocos(Schw.)Wolf),the dried sclerotium of a polyporaceae fungus,was first documented in Shennong’s Classic of Materia Medica and has been used therapeutically and dietarily in China for millennia.Traditionally recognized for its diuretic,spleen-tonifying,and sedative properties,modern pharmacological studies confirm that Poria exhibits antioxidant,anti-inflammatory,antibacterial,and antitumor activities.Pachymic acid(PA;a triterpenoid with the chemical structure 3β-acetyloxy-16α-hydroxy-lanosta-8,24(31)-dien-21-oic acid),isolated from Poria,is a principal bioactive constituent.Emerging evidence indicates PA exerts antitumor effects through multiple mechanisms,though these remain incompletely characterized.Neuroblastoma(NB),a highly malignant pediatric extracranial solid tumor accounting for 15%of childhood cancer deaths,urgently requires safer therapeutics due to the limitations of current treatments.Although PA shows multi-mechanistic antitumor potential,its efficacy against NB remains uncharacterized.This study systematically investigated the potential molecular targets and mechanisms underlying the anti-NB effects of PA by integrating network pharmacology-based target prediction with experimental validation of multi-target interactions through molecular docking,dynamic simulations,and in vitro assays,aimed to establish a novel perspective on PA’s antitumor activity and explore its potential clinical implications for NB treatment by integrating computational predictions with biological assays.Methods This study employed network pharmacology to identify potential targets of PA in NB,followed by validation using molecular docking,molecular dynamics(MD)simulations,MM/PBSA free energy analysis,RT-qPCR and Western blot experiments.Network pharmacology analysis included target screening via TCMSP,GeneCards,DisGeNET,SwissTargetPrediction,SuperPred,and PharmMapper.Subsequently,potential targets were predicted by intersecting the results from these databases via Venn analysis.Following target prediction,topological analysis was performed to identify key targets using Cytoscape software.Molecular docking was conducted using AutoDock Vina,with the binding pocket defined based on crystal structures.MD simulations were performed for 100 ns using GROMACS,and RMSD,RMSF,SASA,and hydrogen bonding dynamics were analyzed.MM/PBSA calculations were carried out to estimate the binding free energy of each protein-ligand complex.In vitro validation included RT-qPCR and Western blot,with GAPDH used as an internal control.Results The CCK-8 assay demonstrated a concentration-dependent inhibitory effect of PA on NB cell viability.GO analysis suggested that the anti-NB activity of PA might involve cellular response to chemical stress,vesicle lumen,and protein tyrosine kinase activity.KEGG pathway enrichment analysis suggested that the anti-NB activity of PA might involve the PI3K/AKT,MAPK,and Ras signaling pathways.Molecular docking and MD simulations revealed stable binding interactions between PA and the core target proteins AKT1,EGFR,SRC,and HSP90AA1.RT-qPCR and Western blot analyses further confirmed that PA treatment significantly decreased the mRNA and protein expression of AKT1,EGFR,and SRC while increasing the HSP90AA1 mRNA and protein levels.Conclusion It was suggested that PA may exert its anti-NB effects by inhibiting AKT1,EGFR,and SRC expression,potentially modulating the PI3K/AKT signaling pathway.These findings provide crucial evidence supporting PA’s development as a therapeutic candidate for NB.
文摘Equipment systems-of-systems （SOS） effectiveness evaluation can provide important reference for construction and optimization of the equipment SoS. After discussing the basic theory and methods of parallel experiments, we depict an SoS effectiveness analysis and evaluation method using parallel expe- riments theory in detail. A case study is carried out which takes the missile defense system as an example. An artificial system of the missile defense system is constructed with the multi-agent modeling method. Then, single factor, multiple factors and defense position deployment computational experiments are carried out and evaluated with the statistical analysis method. Experiment re- sults show that the altitude of the secondary interception missile is not the key factor which affects SoS effectiveness and putting the defense position ahead will increase defense effectiveness. The case study demonstrates the feasibility of the proposed method.
基金Projects(51674154,51704125,51874188) supported by the National Natural Science Foundation of ChinaProjects(2017T100116,2017T100491,2016M590150,2016M602144) supported by the China Postdoctoral Science Foundation+2 种基金Projects(2017GGX30101,2018GGX109001,ZR2017QEE013) supported by the Natural Science Foundation of Shandong Province,ChinaProject(SKLCRSM18KF012) supported by the State Key Laboratory of Coal Resources and Safe Mining,ChinaProject(2018WLJH76) supported by the Young Scholars Program of Shandong University,China
文摘Soft rock control is a big challenge in underground engineering.As for this problem,a high-strength support technique of confined concrete(CC)arches is proposed and studied in this paper.Based on full-scale mechanical test system of arch,research is made on the failure mechanism and mechanical properties of CC arch.Then,a mechanical calculation model of circular section is established for the arches with arbitrary section and unequal rigidity;a calculation formula is deduced for the internal force of the arch;an analysis is made on the influence of different factors on the internal force of the arch;and a calculation formula is got for the bearing capacity of CC arch through the strength criterion of bearing capacity.With numerical calculation and laboratory experiment,the ultimate bearing capacity and internal force distribution is analyzed for CC arches.The research results show that:1)CC arch is 2.31 times higher in strength than the U-shaped steel arch and has better stability;2)The key damage position of the arch is the two sides;3)Theoretical analysis,numerical calculation and laboratory experiment have good consistency in the internal force distribution,bearing capacity,and deformation and failure modes of the arch.All of that verifies the correctness of the theoretical calculation.Based on the above results,a field experiment is carried out in Liangjia Mine.Compared with the U-shaped steel arch support,CC arch support is more effective in surrounding rock deformation control.The research results can provide a basis for the design of CC arch support in underground engineering.
文摘A mobile robot developed by Wuhan University for full-path hotline inspection on 220 kV transmission lines was presented. With 4 rotating joints and 2 translational ones, such robot is capable of traveling along non- obstaclestraight-line segment and surmounting straight-line segment obstacles as well as transferring between two spans automatically. Lagrange’s equations were utilized to derive dynamic equations of all the links, including items of inertia, coupling inertia, Coriolis acceleration, centripetal acceleration and gravity. And a dynamic response experiment on elemental motions of robot prototype’s travelling along non-obstacle straight-line segment and surmounting obstacles was performed on 220 kV 1∶1 simulative overhanging transmission-line in laboratory. In addition, dynamic numerical simulation was conducted in the corresponding condition. Comparison and analysis on results of experiment and numerical simulation have validated theoretical model and simulation resolution. Therefore, the dynamic model formed hereunder can be used for the study of robot control.
基金Project(50878111) supported by the National Natural Science Foundation of China
文摘Vegetation plays a key role in improving wind environment of residential districts,and is helpful for creating a comfortable and beautiful living environment.The optimal design of vegetation for wind environment improvement in winter was investigated by carrying out field experiments in Heqingyuan residential area in Beijing,and after that,numerical simulation with SPOTE(simulation platform for outdoor thermal environment) experiments for outdoor thermal environment of vegetation was adopted for comparison.The conclusions were summarized as follows:1) By comparing the experimental data with simulation results,it could be concluded that the wind field simulated was consistent with the actual wind field,and the flow distribution impacted by vegetation could be accurately reflected;2) The wind velocity with vegetation was lower than that without vegetation,and the wind velocity was reduced by 46%;3) By adjusting arrangement and types of vegetation in the regions with excessively large wind velocity,the pedestrian-level wind velocity could be obviously improved through the simulation and comparison.
基金This project was supported by the Aeronautics Foundation of China (00E21022).
文摘Flight simulator is an important device and a typical high-performance position and speed servo system used in the hardware-in-the-loop simulation of flight control system. Friction is the main nonlinear resistance in the flight simulator servo system, especially in a low-speed state. Based on the description of dynamic and static models of a nonlinear Stribeck friction model, this paper puts forward sliding mode controller to overcome the friction, whose stability is
基金Supported in part by National Basic Research Program of P. R. China(2005CB321604) in part by National Natural Science Foundation of P. R. China (90207002)
文摘Time synchronization is a critical middleware service of wireless sensor networks. Researchers have already proposed some time synchronization algorithms. However, due to the demands for various synchronization precision, existing time synchronization algorithms often need to be adapted. So it is necessary to evaluate these adapted algorithms before use. Software simulation is a valid and quick way to do it. In this paper, we present a time synchronization simulator, Simsync, for wireless sensor networks. We decompose the packet delay into 6 delay components and model them separately. The frequency of crystal oscillator is modeled as Gaussian. To testify its effectiveness, we simulate the reference broadcast synchronization algorithm (RBS) and the timing-sync synchronization algorithm (TPSN) on Simsync. Simulated results are also presented and analyzed.
基金Project(2007CB209400) supported by the Major State Basic Research and Development Program of ChinaProject(50774093) supported by the National Natural Science Foundation of ChinaProject(200801) supported by Open Research Fund of Hunan Provincial Key of Safe Mining Techniques of Coal Mines
文摘The viscoelastic-plastic creep experiments on soft ore-rock in Jinchuan Mine III were performed under circular increment step load and unload. The experimental data were analyzed according to instantaneous elastic strain, visco-elastic strain, instantaneous plastic strain and visco-plastic strain. The result shows that instantaneous deformation modulus tends to increase with the increase of creep stress; soft rocks enhance the ability to resist instantaneous elastic deformation and instantaneous plastic deformation during the multi-level of load and unload in the cyclic process. In respect of specimen JC1099, the ratio of visco-elastic strain to visco-plastic strain varies from 3.15 to 6.58, and the ratio has decreasing tendency with stress increase as a whole; creep deformation tends to be a steady state at low stress level; soft rocks creep usually embodies accelerated creep properties at high stress level. With the damaging variable and the hardening function introduced, a nonlinear creep model of soft rocks is established, in which the decay creep is described by the nonlinear hardening function H of viscidity coefficient. The model can describe the accelerated creep of soft rocks since the nonlinear damaging evolvement variable D of deformation parameter of rocks is introduced. Three stages of soft rocks creep can be described with the uniform creep equation in the nonlinear creep model. With this nonlinear creep model applied to the creep experiments of the ore-rock of Jinchuan Mine III, the nonlinear creep model＇s curves are in good agreement with experimental data.
基金the National Natural Science Foundation of China (60604009)Aeronautical Science Foundationof China(2006ZC51039)Beijing NOVA Program (2007A017).
文摘As friction, intrinsic steady-state nonlinearity poses a challenging dilemma to the control system of 3-DOF （three degree of freedom） flight simulator, a novel hybrid control strategy of nonlinear PID （proportionalintegral-derivative） with additional FFC （feed-forward controller） is proposed, and the hardware-in-the-loop simulation results are also given. Based on the description of 3-DOF flight simulator, a novel nonlinear PID theory is well introduced. Then a nonlinear PID controller with additional FFC is designed. Subsequently, the loop structure of 3-DOF flight simulator is also designed. Finally, a series of hardware-in-the-loop simulation experiments are undertaken to verify the feasibility and effectiveness of the proposed nonlinear PID controller with additional FFC for 3-DOF flight simulator.
基金Project(50408020) supported by the National Natural Science Foundation of Chinaproject(05-0686) supported by the Program of New Century Excellent Talents in Universityproject(200550) supported by the Foundation for the Author of National Excellent Doctoral Dissertation of China
文摘To determine the ultimate bearing capacity of foundations on sloping ground surface in practice, energy dissipation method was used to formulate the beating capacity as programming problem, and full-scale model experiments were investigated to analyze the performance of the soil slopes loaded by a strip footing in laboratory. The soil failure is governed by a linear Mohr-Coulomb yield criterion, and soil deformation follows an associated flow rule. Based on the energy dissipation method of plastic mechanics, a multi-wedge translational failure mechanism was employed to obtain the three bearing capacity factors related to cohesion, equivalent surcharge load and the unit gravity for various slope inclination angles. Numerical results were compared with those of the published solutions using finite element method and those of model experiments. The bearing capacity factors were presented in the form of design charts for practical use in engineering. The results show that limit analysis solutions approximate to those of model tests, and that the energy dissipation method is effective to estimate bearing capacity of soil slope.
基金This project was supported by the Aeronautics Foundation of China (00E51022).
文摘To improve the robustness of high-precision servo systems, quantitative feedback theory （QFT） which aims to achieve a desired robust design over a specified region of plant uncertainty is proposed. The robust design problem can be solved using QFT but it fails to guarantee a high precision tracking. This problem is solved by a robust digital QFT control scheme based on zero phase error （ZPE） feed forward compensation. This scheme consists of two parts： a QFT controller in the closed-loop system and a ZPE feed-forward compensator. Digital QFT controller is designed to overcome the uncertainties in the system. Digital ZPE feed forward controller is used to improve the tracking precision. Simulation and real-time examples for flight simulator servo system indicate that this control scheme can guarantee both high robust performance and high position tracking precision.
基金Supported by Funding(2016YFD0701600)from Research and Development of Potato Harvesting Technology and EquipmentSpecial Funds for Construction of Modern Agricultural Technology System(CARS-10-P22)Study on Key Technical Equipment for Scale of Potato Planting(GA15B401)
文摘In order to solve the problems which are widespread in potato seeding planter, such as lower operating efficiency, unideal performance index, higher replay rate and leakage rate and uneven spacing sowing in seeding operating, a trailed potato fertilization seeder was designed. The key components of the special structure had been got through the description of the structure and working principle of the whole machine. A crossing seed-taken technology along with the vibration component was adopted to achieve precision seeding. The results showed in the feld test of the machine： all the performance indexes of the machine met the agronomic requirement of potato planting; the multiple and missing index were low; it completed the ditching, fertilizing, seeding as well as ridging in one planting process; its operation effciency was high and the stability was good. This design of the trailed potato fertilization seeder provided a reference for the development of large traction-type potato seeding machine.
基金Supported by National Scientific Foundation of China(Study on of Basis Theory and Prediction of Debris Flow,40025103)
文摘In order to improve and enhance the numerical modeling methods and its application on debris flow problems,a preliminary study has been proposed in accordance with the corrected water-sediment numerical model on the premise of revised resistance and sediment capacity equations.Firstly,an overview the recent re- search achievements on numerical simulation of debris flow has been conducted,the results shown that a gener- al numerical model for debris flow can not be existed at all because the complex rheol...
