Bear bile has been a valuable and effective medicinal material in traditional Chinese medicine(TCM)for over 13 centuries.However,the current practice of obtaining it through bear farming is under scrutiny for its adve...Bear bile has been a valuable and effective medicinal material in traditional Chinese medicine(TCM)for over 13 centuries.However,the current practice of obtaining it through bear farming is under scrutiny for its adverse impact on bear welfare.Here,we present a new approach for creating artificial bear bile(ABB)as a high-quality and sustainable alternative to natural bear bile.This study addresses the scientific challenges of creating bear bile alternatives through interdisciplinary collaborations across various fields,including resources,chemistry,biology,medicine,pharmacology,and TCM.A comprehensive efficacy assessment system that bridges the gap between TCM and modern medical terminology has been established,allowing for the systematic screening of therapeutic constituents.Through the utilization of chemical synthesis and enzyme engineering technologies,our research has achieved the environmentally friendly,large-scale production of bear bile therapeutic compounds,as well as the optimization and recomposition of ABB formulations.The resulting ABB not only closely resembles natural bear bile in its composition but also offers advantages such as consistent product quality,availability of raw materials,and independence from threatened or wild resources.Comprehensive preclinical efficacy evaluations have demonstrated the equivalence of the therapeutic effects from ABB and those from commercially available drained bear bile(DBB).Furthermore,preclinical toxicological assessment and phase I clinical trials show that the safety of ABB is on par with that of the currently used DBB.This innovative strategy can serve as a new research paradigm for developing alternatives for other endangered TCMs,thereby strengthening the integrity and sustainability of TCM.展开更多
The pneumatic vibration isolator(PVI)plays an increasingly important role in precision manufacturing.In this paper,aiming to detect the performance of the pressure regulator in the PVI system,a PVI testing system with...The pneumatic vibration isolator(PVI)plays an increasingly important role in precision manufacturing.In this paper,aiming to detect the performance of the pressure regulator in the PVI system,a PVI testing system with a pressure regulator is designed and developed.Firstly,the structure of the pneumatic spring is presented and analyzed,and the nonlinear stiffness is obtained based on the ideal gas model and material mechanics.Then,according to the working principle and continuity equations of ideal airflow,a dynamic model of the PVI system with a pressure regulator is established.Through the simulation analysis,the vibration isolation performance is improved with the efficient and precise pressure regulator.The average values of both the vibration velocity and transmission rate decrease when the vibration is set to 4,10,20 and 40 Hz,respectively.The experiments demonstrate the reliability and effectiveness of the pressure regulator.This achievement will become an important basis for future research concerning precision manufacturing.展开更多
Platelets aggregation and thrombosis formation are major reasons of cardiovascular and cerebral vascular diseases.To develop novel,effective and safe agents for inhibiting platelet aggregation and preventing above dis...Platelets aggregation and thrombosis formation are major reasons of cardiovascular and cerebral vascular diseases.To develop novel,effective and safe agents for inhibiting platelet aggregation and preventing above diseases is urgently needed.Some traditional Chinese medicines for“Houxue Huayu”have been shown to inhibit platelet aggregation potently.They are used frequently in China and also in Asian countries.Recently,the major effective components of Pueraria lobata,Salvia miltiorrhiza Bunge,Apium graveolens L.and so on were studied.The mechanisms and the molecular targets of puerarin,salvianolic acid B and the analogue of 3-n-butylphthalide,dl-PHPB were investigated.Four platelet aggregation inducers,ADP,arachidonic acid(AA),collagen(Col)and thrombin,were used in the study.展开更多
The discharge characteristics and mechanism of sub-millimeter pulsed dielectric barrier discharge in atmosphericpressure helium are investigated experimentally and theoretically, demonstrating that when the discharge ...The discharge characteristics and mechanism of sub-millimeter pulsed dielectric barrier discharge in atmosphericpressure helium are investigated experimentally and theoretically, demonstrating that when the discharge gap distance is reduced from 1.00 mm to 0.20 mm, the discharge ignition time is reduced to approximately 40 ns and discharge intensity is enhanced in terms of the discharge optical emission intensity and density of the plasma species,(energetic electrons with energy above 8.40 e V). The simulated results show that as the discharge gap distance is further reduced to 0.10 mm,the number of energetic electrons decreases, which is attributable to the contraction of plasma bulk regime and reduction of electron density in the discharge bulk. Conversely, the proportion of energetic electrons to the total electrons in the discharge monotonically increases as the discharge gap distance is reduced from 1.00 mm to 0.10 mm. It is proposed that a gap distance of 0.12 mm is optimal to achieve a high concentration and proportion of energetic electrons in sub-millimeter pulsed atmosphere dielectric barrier discharge.展开更多
Boundary layer ingesting(BLI)fans are required to operate under distorted inflow conditions,which significantly reduces their efficiency[1,2].Accurately predicting fan losses is crucial for designing high-performance,...Boundary layer ingesting(BLI)fans are required to operate under distorted inflow conditions,which significantly reduces their efficiency[1,2].Accurately predicting fan losses is crucial for designing high-performance,distortion-tolerant fans.展开更多
In the era of intelligent revolution,pneumatic artificial muscle(PAM)actuators have gained significance in robotics,particularly for tasks demanding high safety and flexibility.Despite their inherent flexibility,PAMs ...In the era of intelligent revolution,pneumatic artificial muscle(PAM)actuators have gained significance in robotics,particularly for tasks demanding high safety and flexibility.Despite their inherent flexibility,PAMs encounter challenges in practical applications because of their complex material properties,including hysteresis,nonlinearity,and low response frequencies,which hinder precise modeling and motion control,limiting their widespread adoption.This study focuses on fuzzy logic dynamic surface control(DSC)for PAMs,addressing full-state constraints and unknown disturbances.We propose an improved neural DSC method,combining enhanced DSC techniques with fuzzy logic system approximation and parameter minimization for PAM systems.The introduction of a novel barrier Lyapunov function during system design effectively resolves full-state constraint issues.A key feature of this control approach is its single online estimation parameter update while maintaining stability characteristics akin to the conventional backstepping method.Importantly,it ensures constraint adherence even in the presence of disturbances.Lyapunov stability analysis confirms signal boundedness within the closed-loop system.Experimental results validate the algorithm’s effectiveness in enhancing control precision and response speed.展开更多
Crystal orientation governs the plasticity of intermetallic alloys,yet the atomicscale mechanisms linking defect dynamics to mechanical properties remain elusive.Here,we unveil unprecedented deformation pathways in si...Crystal orientation governs the plasticity of intermetallic alloys,yet the atomicscale mechanisms linking defect dynamics to mechanical properties remain elusive.Here,we unveil unprecedented deformation pathways in single-crystal γ-TiAl through largescale molecular dynamics simulations under uniaxial tension across four crystallographic orientations:[100],[112],[110],and[111].Strikingly,a metastable body-centered cubic(BCC)phase emerges transiently during[100]-oriented stretching,acting as a critical bridge between elastic and plastic regimes—a phenomenon unreported in γ-TiAl.For[110]and[111]orientations,we identify a hierarchical defect evolution cascade(intrinsic stacking faults→extrinsic stacking faults→twin boundary(ISF→ESF→TB))driven by intersecting stacking faults and Shockley partial dislocation interactions,which govern twin boundary nucleation and growth.In contrast,[112]-oriented deformation adheres to conventional dislocation-mediated plasticity.These findings reveal how crystallographic anisotropy dictates defect dynamics,offering atomic-scale insights into deformation twinning and transient phase transitions.This work bridges atomistic processes to macroscopic properties,advancing the design of next-generation lightweight hightemperature materials.展开更多
This paper presents an adaptive saturated integral sliding mode controller(ASISMC)integrated with an adaptive extended state observer(AESO)to address the challenges of nonlinear time-varying characteristics,parameter ...This paper presents an adaptive saturated integral sliding mode controller(ASISMC)integrated with an adaptive extended state observer(AESO)to address the challenges of nonlinear time-varying characteristics,parameter uncertainties,and external disturbances in valve positioner systems(VPS).To begin with,the VPS dynamic model is established by combining the valve positioner model,the control valve model,and the Euler-Lagrange model,where the uncertain parameters are estimated using the adaptive laws.Moreover,a tracking differentiator(TD)is implemented to ensure smooth and continuous signal processing.The AESO with structural self-regulation capability is also developed to estimate system perturbations and uncertainties effectively.Meanwhile,the proposed ASISMC is designed using adaptive laws based on the backstepping technique,further enhanced by setting saturation constraints on the integral sliding film surface.Finally,experimental validation confirms the superiority of the proposed approach over existing methods in improving control precision,response velocity,and disturbance rejection capability.展开更多
Potassium 2-(1-hydroxypentyl)-benzoate(PHPB) is a novel drug candidate for acute ischemic stroke. PHPB has been also shown to be beneficial for some neurodegenerative diseases. In this study, we demonstrated that PHPB...Potassium 2-(1-hydroxypentyl)-benzoate(PHPB) is a novel drug candidate for acute ischemic stroke. PHPB has been also shown to be beneficial for some neurodegenerative diseases. In this study, we demonstrated that PHPB improved depressive-like behaviors induced by chronic unpredictable mild stress(CUMS) in rats. Male SD rats were subjected to the stress for five weeks. PHPB(30 and 100 mg/kg) or fluoxetine(FLX 10 mg/kg, as positive control) was administered orally from the third week in CUMS procedure. The behavioral tests were applied and then the biochemical studies were carried out. PHPB or FLX treatment rescued the behavioral deficiency in CUMS-exposed rats. Meanwhile, PHPB normalized the enhanced level of serum corticosterone, improved hippocampal and serum BDNF levels, as well as p-CREB level in hippocampus. In addition, PHPB could reverse the reduced level of extracellular 5-HT and its metabolite 5-HIAA in prefrontal cortex(PFC) of depressed rats. In summary, our results showed that PHPB improved depression-like behaviors in CUMS-exposed rats. The mechanisms might relate to the reverse of neurotrophic disturbance in the brain, reducing excessive HPA axis response and facilitating the release of 5-HT.展开更多
Surface moisture or humidity impacting the lubrication property is a ubiquitous phenomenon in tribological systems,which is demonstrated by a combination of molecular dynamics(MD)simulation and experiment for the orga...Surface moisture or humidity impacting the lubrication property is a ubiquitous phenomenon in tribological systems,which is demonstrated by a combination of molecular dynamics(MD)simulation and experiment for the organic friction modifier(OFM)-containing lubricant.The stearic acid and poly-α-olefin 4cSt(PAO4)were chosen as the OFM and base oil molecules,respectively.The physical adsorption indicates that on the moist surface water molecules are preferentially adsorbed on friction surface,and even make OFM adsorption film thoroughly leave surface and mix with base oil.In shear process,the adsorption of water film and desorption OFM film are further enhanced,particularly under higher shear rate.The simulated friction coefficient(that is proportional to shear rate)increases firstly and then decreases with thickening water film,in good agreement with experiments,while the slip length shows a contrary change.The wear increases with humidity due to tribochemistry revealing the continuous formation and removal of Si–O–Si network.The tribological discrepancy of OFM-containing lubricant in dry and humid conditions is attributed to the slip plane’s transformation from the interface between OFM adsorption film and lubricant bulk to the interface between adsorbed water films.This work provides a new thought to understand the boundary lubrication and failure of lubricant in humid environments,likely water is not always harmful in oil lubrication systems.展开更多
基金supported by the Major Program of National Natural Science Foundation of China(T2192970-T2192974)the CAMS Innovation Fund for Medical Sciences(CIFMS,2021-I2M-1-027).
文摘Bear bile has been a valuable and effective medicinal material in traditional Chinese medicine(TCM)for over 13 centuries.However,the current practice of obtaining it through bear farming is under scrutiny for its adverse impact on bear welfare.Here,we present a new approach for creating artificial bear bile(ABB)as a high-quality and sustainable alternative to natural bear bile.This study addresses the scientific challenges of creating bear bile alternatives through interdisciplinary collaborations across various fields,including resources,chemistry,biology,medicine,pharmacology,and TCM.A comprehensive efficacy assessment system that bridges the gap between TCM and modern medical terminology has been established,allowing for the systematic screening of therapeutic constituents.Through the utilization of chemical synthesis and enzyme engineering technologies,our research has achieved the environmentally friendly,large-scale production of bear bile therapeutic compounds,as well as the optimization and recomposition of ABB formulations.The resulting ABB not only closely resembles natural bear bile in its composition but also offers advantages such as consistent product quality,availability of raw materials,and independence from threatened or wild resources.Comprehensive preclinical efficacy evaluations have demonstrated the equivalence of the therapeutic effects from ABB and those from commercially available drained bear bile(DBB).Furthermore,preclinical toxicological assessment and phase I clinical trials show that the safety of ABB is on par with that of the currently used DBB.This innovative strategy can serve as a new research paradigm for developing alternatives for other endangered TCMs,thereby strengthening the integrity and sustainability of TCM.
基金National Key Research and Development Project(Grant No.2021YFC0122502)Youth Fund of National Natural Science Foundation of China(Grant Nos.52105044,52105046).
文摘The pneumatic vibration isolator(PVI)plays an increasingly important role in precision manufacturing.In this paper,aiming to detect the performance of the pressure regulator in the PVI system,a PVI testing system with a pressure regulator is designed and developed.Firstly,the structure of the pneumatic spring is presented and analyzed,and the nonlinear stiffness is obtained based on the ideal gas model and material mechanics.Then,according to the working principle and continuity equations of ideal airflow,a dynamic model of the PVI system with a pressure regulator is established.Through the simulation analysis,the vibration isolation performance is improved with the efficient and precise pressure regulator.The average values of both the vibration velocity and transmission rate decrease when the vibration is set to 4,10,20 and 40 Hz,respectively.The experiments demonstrate the reliability and effectiveness of the pressure regulator.This achievement will become an important basis for future research concerning precision manufacturing.
文摘Platelets aggregation and thrombosis formation are major reasons of cardiovascular and cerebral vascular diseases.To develop novel,effective and safe agents for inhibiting platelet aggregation and preventing above diseases is urgently needed.Some traditional Chinese medicines for“Houxue Huayu”have been shown to inhibit platelet aggregation potently.They are used frequently in China and also in Asian countries.Recently,the major effective components of Pueraria lobata,Salvia miltiorrhiza Bunge,Apium graveolens L.and so on were studied.The mechanisms and the molecular targets of puerarin,salvianolic acid B and the analogue of 3-n-butylphthalide,dl-PHPB were investigated.Four platelet aggregation inducers,ADP,arachidonic acid(AA),collagen(Col)and thrombin,were used in the study.
基金Project supported by the National Natural Science Foundation of China (Grant Nos.12175036 and 11875104)。
文摘The discharge characteristics and mechanism of sub-millimeter pulsed dielectric barrier discharge in atmosphericpressure helium are investigated experimentally and theoretically, demonstrating that when the discharge gap distance is reduced from 1.00 mm to 0.20 mm, the discharge ignition time is reduced to approximately 40 ns and discharge intensity is enhanced in terms of the discharge optical emission intensity and density of the plasma species,(energetic electrons with energy above 8.40 e V). The simulated results show that as the discharge gap distance is further reduced to 0.10 mm,the number of energetic electrons decreases, which is attributable to the contraction of plasma bulk regime and reduction of electron density in the discharge bulk. Conversely, the proportion of energetic electrons to the total electrons in the discharge monotonically increases as the discharge gap distance is reduced from 1.00 mm to 0.10 mm. It is proposed that a gap distance of 0.12 mm is optimal to achieve a high concentration and proportion of energetic electrons in sub-millimeter pulsed atmosphere dielectric barrier discharge.
基金supported by the National Key Research and Development Program(Grant No.2022YFF0708903)the Ningbo Key Technology Re-search and Development Program(Grant No.2023Z018)+3 种基金the National Natural Science Foundation of China(Grant No.52275043)the Youth Fund of National Natural Science Foundation of China(Grant Nos.72301015,52105046)the Young Elite Scientist Sponsorship Program by China Association for Science and Technology(Grant Nos.2022QNRC001,YESS20220292)the Liupanshan Laboratory Basic Research Program(Grant No.LPS-2024-KY-D-JC-0009)。
文摘Boundary layer ingesting(BLI)fans are required to operate under distorted inflow conditions,which significantly reduces their efficiency[1,2].Accurately predicting fan losses is crucial for designing high-performance,distortion-tolerant fans.
基金supported by the National Key Research and Development Program of China(Grant No.2022YFF0708903)in part by the Ningbo Key Technology Research and Development Program of China(Grant No.2023Z018)+1 种基金in part by the National Natural Science Foundation of China(Grant No.52275043)in part by the Zhejiang Lab Open Research Project of China(Grant No.121001-AB2212).
文摘In the era of intelligent revolution,pneumatic artificial muscle(PAM)actuators have gained significance in robotics,particularly for tasks demanding high safety and flexibility.Despite their inherent flexibility,PAMs encounter challenges in practical applications because of their complex material properties,including hysteresis,nonlinearity,and low response frequencies,which hinder precise modeling and motion control,limiting their widespread adoption.This study focuses on fuzzy logic dynamic surface control(DSC)for PAMs,addressing full-state constraints and unknown disturbances.We propose an improved neural DSC method,combining enhanced DSC techniques with fuzzy logic system approximation and parameter minimization for PAM systems.The introduction of a novel barrier Lyapunov function during system design effectively resolves full-state constraint issues.A key feature of this control approach is its single online estimation parameter update while maintaining stability characteristics akin to the conventional backstepping method.Importantly,it ensures constraint adherence even in the presence of disturbances.Lyapunov stability analysis confirms signal boundedness within the closed-loop system.Experimental results validate the algorithm’s effectiveness in enhancing control precision and response speed.
基金financial support by the National Science and Technology Major Project(No.2025ZD0618600)the General Projects for Key Industrial Chain Technology Research and Development of Xi'an(No.24ZDCYJSGG0050)the Key Technology Project of Ningbo"Science and Technology Innovation Yongjiang 2035"(No.2024Z155).
文摘Crystal orientation governs the plasticity of intermetallic alloys,yet the atomicscale mechanisms linking defect dynamics to mechanical properties remain elusive.Here,we unveil unprecedented deformation pathways in single-crystal γ-TiAl through largescale molecular dynamics simulations under uniaxial tension across four crystallographic orientations:[100],[112],[110],and[111].Strikingly,a metastable body-centered cubic(BCC)phase emerges transiently during[100]-oriented stretching,acting as a critical bridge between elastic and plastic regimes—a phenomenon unreported in γ-TiAl.For[110]and[111]orientations,we identify a hierarchical defect evolution cascade(intrinsic stacking faults→extrinsic stacking faults→twin boundary(ISF→ESF→TB))driven by intersecting stacking faults and Shockley partial dislocation interactions,which govern twin boundary nucleation and growth.In contrast,[112]-oriented deformation adheres to conventional dislocation-mediated plasticity.These findings reveal how crystallographic anisotropy dictates defect dynamics,offering atomic-scale insights into deformation twinning and transient phase transitions.This work bridges atomistic processes to macroscopic properties,advancing the design of next-generation lightweight hightemperature materials.
基金supported by the National Key Research and Development Program of China(Grant No.2022YFF0708902)the Ningbo Key Technology Research and Development Program(Grant No.2023Z018)+1 种基金the Liupanshan Laboratory Basic Research Program(Grant No.LPS-2024-KY-D-JC-0008)the Youth Fund of National Natural Science Foundation of China(Grant No.52205043)。
文摘This paper presents an adaptive saturated integral sliding mode controller(ASISMC)integrated with an adaptive extended state observer(AESO)to address the challenges of nonlinear time-varying characteristics,parameter uncertainties,and external disturbances in valve positioner systems(VPS).To begin with,the VPS dynamic model is established by combining the valve positioner model,the control valve model,and the Euler-Lagrange model,where the uncertain parameters are estimated using the adaptive laws.Moreover,a tracking differentiator(TD)is implemented to ensure smooth and continuous signal processing.The AESO with structural self-regulation capability is also developed to estimate system perturbations and uncertainties effectively.Meanwhile,the proposed ASISMC is designed using adaptive laws based on the backstepping technique,further enhanced by setting saturation constraints on the integral sliding film surface.Finally,experimental validation confirms the superiority of the proposed approach over existing methods in improving control precision,response velocity,and disturbance rejection capability.
基金supported by grants of National Nature Science Foundation of China (No. 81573417)the CAMS Initiative for Innovative Medicine (CAMS-I2M-1-010, China)the Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study (BZ0150, China)
文摘Potassium 2-(1-hydroxypentyl)-benzoate(PHPB) is a novel drug candidate for acute ischemic stroke. PHPB has been also shown to be beneficial for some neurodegenerative diseases. In this study, we demonstrated that PHPB improved depressive-like behaviors induced by chronic unpredictable mild stress(CUMS) in rats. Male SD rats were subjected to the stress for five weeks. PHPB(30 and 100 mg/kg) or fluoxetine(FLX 10 mg/kg, as positive control) was administered orally from the third week in CUMS procedure. The behavioral tests were applied and then the biochemical studies were carried out. PHPB or FLX treatment rescued the behavioral deficiency in CUMS-exposed rats. Meanwhile, PHPB normalized the enhanced level of serum corticosterone, improved hippocampal and serum BDNF levels, as well as p-CREB level in hippocampus. In addition, PHPB could reverse the reduced level of extracellular 5-HT and its metabolite 5-HIAA in prefrontal cortex(PFC) of depressed rats. In summary, our results showed that PHPB improved depression-like behaviors in CUMS-exposed rats. The mechanisms might relate to the reverse of neurotrophic disturbance in the brain, reducing excessive HPA axis response and facilitating the release of 5-HT.
基金the financial support from the National Natural Science Foundation of China(52105210)Project funded by China Postdoctoral Science Foundation(2022M712593)+1 种基金Research Fund of the State Key Laboratory of Solidification Processing(NPU)(2021-TS-06)Zhejiang Provincial Natural Science Foundation of China(Key Program,Grant No.LZ21A020001).
文摘Surface moisture or humidity impacting the lubrication property is a ubiquitous phenomenon in tribological systems,which is demonstrated by a combination of molecular dynamics(MD)simulation and experiment for the organic friction modifier(OFM)-containing lubricant.The stearic acid and poly-α-olefin 4cSt(PAO4)were chosen as the OFM and base oil molecules,respectively.The physical adsorption indicates that on the moist surface water molecules are preferentially adsorbed on friction surface,and even make OFM adsorption film thoroughly leave surface and mix with base oil.In shear process,the adsorption of water film and desorption OFM film are further enhanced,particularly under higher shear rate.The simulated friction coefficient(that is proportional to shear rate)increases firstly and then decreases with thickening water film,in good agreement with experiments,while the slip length shows a contrary change.The wear increases with humidity due to tribochemistry revealing the continuous formation and removal of Si–O–Si network.The tribological discrepancy of OFM-containing lubricant in dry and humid conditions is attributed to the slip plane’s transformation from the interface between OFM adsorption film and lubricant bulk to the interface between adsorbed water films.This work provides a new thought to understand the boundary lubrication and failure of lubricant in humid environments,likely water is not always harmful in oil lubrication systems.
