As the environmental problems become increasingly serious,distributed electrical propulsion systems with higher aerodynamic efficiency and lower pollution emission have received extensive attention in recent years.The...As the environmental problems become increasingly serious,distributed electrical propulsion systems with higher aerodynamic efficiency and lower pollution emission have received extensive attention in recent years.The distributed electrical propulsion usually employs the new aero-propulsion integrated configuration.A simulation strategy for internal and external flow coupling based on the combination of lifting line theory and body force method is proposed.The lifting line theory and body force method as source term are embedded into the Navier-Stokes formulation.The lift and drag characteristics of the aero-propulsion coupling configuration are simulated.The results indicate that the coupling configuration has the most obvious lift augmentation at 12°angle of attack,which can provide an 11.11%increase in lift for the airfoil.At 0°angle of attack,the pressure difference on the lip parts provides the thrust component,which results in a lower drag coefficient.Additionally,the failure impact of a ducted fan at the middle or edge on aerodynamics is investigated.For the two failure conditions,the lift of the coupling configuration is decreased significantly by 27.85%and 26.14%respectively,and the lip thrust is decreased by 70.74%and 56.48%respectively.展开更多
This study identified six novel azaphilones,isochromophilones G-L(1-6),and three novel biosynthetically related congeners(7-9)from Diaporthe sp.SCSIO 41011.The structures and absolute configurations were elucidated th...This study identified six novel azaphilones,isochromophilones G-L(1-6),and three novel biosynthetically related congeners(7-9)from Diaporthe sp.SCSIO 41011.The structures and absolute configurations were elucidated through comprehensive spectroscopic analyses combined with experimental and calculated electronic circular dichroism(ECD)spectra.Significantly,three highly oxygenated azaphilones contain an acetyl group at the terminal chain(4)or linear conjugated polyenoid moieties(5 and 6),which occur infrequently in the azaphilone family.Additionally,several compounds demonstrated inhibition of lipopolysaccharide(LPS)-induced nuclear factor kappa-B(NF-κB)activation in RAW 264.7 macrophages at 20μmol·L^(-1).The novel compound(1)effectively inhibited receptor activator of NF-κB ligand(RANKL)-induced osteoclast differentiation without exhibiting cytotoxicity in bone marrow and RAW264.7 macrophages,indicating its potential as a promising lead compound for osteolytic disease treatment.This research presents the first documented evidence of azaphilone derivatives as inhibitors of RANKL-induced osteoclastogenesis.展开更多
Autophagy is a highly conserved degradation process in which intracellular components are engulfed into a double membrane structure,known as the autophagosomes,and then delivered to lysosomes/vacuoles for degradation(...Autophagy is a highly conserved degradation process in which intracellular components are engulfed into a double membrane structure,known as the autophagosomes,and then delivered to lysosomes/vacuoles for degradation(Ohsumi,2014).Recently,autophagy has been found to be responsible for maintaining glucose homeostasis in adult animals(Karsli-Uzunbas et al.,2014).However,the molecular mechanism underlying energy deprivation-induced autophagy remains relatively unclear.展开更多
A unified power flow controller(UPFC)combines the advantages of various flexible alternating current transmission system(FACTS)devices into a powerful format.Using a 500 kV power grid,this study evaluates the selectio...A unified power flow controller(UPFC)combines the advantages of various flexible alternating current transmission system(FACTS)devices into a powerful format.Using a 500 kV power grid,this study evaluates the selection and use of a UPFC to improve transmission capacity.The"UPFC unit capacity control proportionality coefficient"is introduced to quantify the control effect of the UPFC,and an optimal calculation method for the UPFC capacity is presented.Following the proposal of a UPFC site selection process,the data of an existing power grid is used to conduct simulations.The simulation results show that the UPFC has a strong ability to improve transmission capacity,and its use is greatly advantageous.Additionally,by applying the proposed selection method,the control effect and economic benefits of the UPFC can be comprehensively considered during project site selection.These findings have a guiding significance for UPFC site selection in ultra-high voltage power grids.展开更多
Adding the auxiliary frequency control function to the wind turbine generator(WTG)is a solution to the frequency security problem of the power system caused by the replacement of the synchronous generator(SG)by the WT...Adding the auxiliary frequency control function to the wind turbine generator(WTG)is a solution to the frequency security problem of the power system caused by the replacement of the synchronous generator(SG)by the WTG.The auxiliary frequency control using rotor kinetic energy is an economical scheme because the WTG still runs at the maximum power point during normal operation.In this paper,the functional optimization model of the auxiliary frequency control strategy of WTG is established.The optimal auxiliary frequency control strategy is obtained by solving the model numerically.As for the practical realization of the control strategy,the coordination of the auxiliary frequency control with the maximum power point tracking(MPPT)control is studied.The practical auxiliary frequency control strategy is modified to adapt to different power disturbances in the system,and the parameter setting method is also proposed.The sensitivity of system frequency to control parameters is studied.Finally,the simulation results verify the effectiveness and practicability of the proposed control strategy.展开更多
As the crucial powerhouse for cell metabolism and tissue survival,the mitochondrion frequently undergoes morphological or positional changes when responding to various stresses and energy demands.In addition to intrac...As the crucial powerhouse for cell metabolism and tissue survival,the mitochondrion frequently undergoes morphological or positional changes when responding to various stresses and energy demands.In addition to intracellular changes,mitochondria can also be transferred intercellularly.Besides restoring stressed cells and damaged tissues due to mitochondrial dysfunction,the intercellular mitochondrial transfer also occurs under physiological conditions.In this review,the phenomenon of mitochondrial transfer is described according to its function under both physiological and pathological conditions,including tissue homeostasis,damaged tissue repair,tumor progression,and immunoregulation.Then,the mechanisms that contribute to this process are summarized,such as the trigger factors and transfer routes.Furthermore,various perspectives are explored to better understand the mysteries of cell-cell mitochondrial trafficking.In addition,potential therapeutic strategies for mitochondria-targeted application to rescue tissue damage and degeneration,as well as the inhibition of tumor progression,are discussed.展开更多
For AC transmission lines connected to an LCC-HVDC inverter station,commutation failure can lead to the wrong operation of traditional protection.To solve the problem,this paper proposes a fast protection scheme using...For AC transmission lines connected to an LCC-HVDC inverter station,commutation failure can lead to the wrong operation of traditional protection.To solve the problem,this paper proposes a fast protection scheme using transient information from one end of the AC line.The boundary frequency characteristics of the AC line connected to LCC-HVDC inverter are analyzed first.This reveals the existence of significant attenuation on both high frequency signals and some specific frequency signals.Based on the boundary characteristics,a novel boundary protection principle utilizing a backward traveling wave is then proposed.A PSCAD/EMTDC simulation model of a±800 kV LCC-HVDC and 500 kV AC transmission system is established,and different fault cases are simulated.The simulation results prove that the novel protection principle is immune to commutation failure,fault resistance and fault type.展开更多
基金the funding support from the Taihang Laboratory,China(No.D2024-1-0201).
文摘As the environmental problems become increasingly serious,distributed electrical propulsion systems with higher aerodynamic efficiency and lower pollution emission have received extensive attention in recent years.The distributed electrical propulsion usually employs the new aero-propulsion integrated configuration.A simulation strategy for internal and external flow coupling based on the combination of lifting line theory and body force method is proposed.The lifting line theory and body force method as source term are embedded into the Navier-Stokes formulation.The lift and drag characteristics of the aero-propulsion coupling configuration are simulated.The results indicate that the coupling configuration has the most obvious lift augmentation at 12°angle of attack,which can provide an 11.11%increase in lift for the airfoil.At 0°angle of attack,the pressure difference on the lip parts provides the thrust component,which results in a lower drag coefficient.Additionally,the failure impact of a ducted fan at the middle or edge on aerodynamics is investigated.For the two failure conditions,the lift of the coupling configuration is decreased significantly by 27.85%and 26.14%respectively,and the lip thrust is decreased by 70.74%and 56.48%respectively.
基金supported by the National Natural Science Foundation of China(No.82260692)Guangxi Natural Science Foundation(No.2024GXNSFFA010004)+2 种基金Bagui Youth Talent Development ProgramHigh-Level Talent Training Project Foundation of Guangxi University of Chinese Medicine(Nos.202407 and 2022C038)the Innovation Project of Guangxi Graduate Education(No.YCSW2025457)。
文摘This study identified six novel azaphilones,isochromophilones G-L(1-6),and three novel biosynthetically related congeners(7-9)from Diaporthe sp.SCSIO 41011.The structures and absolute configurations were elucidated through comprehensive spectroscopic analyses combined with experimental and calculated electronic circular dichroism(ECD)spectra.Significantly,three highly oxygenated azaphilones contain an acetyl group at the terminal chain(4)or linear conjugated polyenoid moieties(5 and 6),which occur infrequently in the azaphilone family.Additionally,several compounds demonstrated inhibition of lipopolysaccharide(LPS)-induced nuclear factor kappa-B(NF-κB)activation in RAW 264.7 macrophages at 20μmol·L^(-1).The novel compound(1)effectively inhibited receptor activator of NF-κB ligand(RANKL)-induced osteoclast differentiation without exhibiting cytotoxicity in bone marrow and RAW264.7 macrophages,indicating its potential as a promising lead compound for osteolytic disease treatment.This research presents the first documented evidence of azaphilone derivatives as inhibitors of RANKL-induced osteoclastogenesis.
基金supported by the National Natural Science Foundation of China(32070739,31771528,and 91754107)Zhejiang Provincial Natural Science Foundation of China(LR21C070001)+3 种基金the National Basic Research Program of China(2017YFA0503402)to C.YiNatural Science Foundation for Young Scientists of China(81800085)Natural Science Foundation of Hubei Province,China(ZRMS2020002147)to J.TongZhejiang Key R&D Program of China(2019C02030)to L.Zhang。
文摘Autophagy is a highly conserved degradation process in which intracellular components are engulfed into a double membrane structure,known as the autophagosomes,and then delivered to lysosomes/vacuoles for degradation(Ohsumi,2014).Recently,autophagy has been found to be responsible for maintaining glucose homeostasis in adult animals(Karsli-Uzunbas et al.,2014).However,the molecular mechanism underlying energy deprivation-induced autophagy remains relatively unclear.
基金supported by State Grid Corporation’s Science and Technology Project“Research and Demonstration of Technical Measures for Improving Voltage Supporting Capacity of Large-scale Urban Power Grid”(52094016000Y)
文摘A unified power flow controller(UPFC)combines the advantages of various flexible alternating current transmission system(FACTS)devices into a powerful format.Using a 500 kV power grid,this study evaluates the selection and use of a UPFC to improve transmission capacity.The"UPFC unit capacity control proportionality coefficient"is introduced to quantify the control effect of the UPFC,and an optimal calculation method for the UPFC capacity is presented.Following the proposal of a UPFC site selection process,the data of an existing power grid is used to conduct simulations.The simulation results show that the UPFC has a strong ability to improve transmission capacity,and its use is greatly advantageous.Additionally,by applying the proposed selection method,the control effect and economic benefits of the UPFC can be comprehensively considered during project site selection.These findings have a guiding significance for UPFC site selection in ultra-high voltage power grids.
基金supported by State Grid Corporation of China(No.52094020006V)。
文摘Adding the auxiliary frequency control function to the wind turbine generator(WTG)is a solution to the frequency security problem of the power system caused by the replacement of the synchronous generator(SG)by the WTG.The auxiliary frequency control using rotor kinetic energy is an economical scheme because the WTG still runs at the maximum power point during normal operation.In this paper,the functional optimization model of the auxiliary frequency control strategy of WTG is established.The optimal auxiliary frequency control strategy is obtained by solving the model numerically.As for the practical realization of the control strategy,the coordination of the auxiliary frequency control with the maximum power point tracking(MPPT)control is studied.The practical auxiliary frequency control strategy is modified to adapt to different power disturbances in the system,and the parameter setting method is also proposed.The sensitivity of system frequency to control parameters is studied.Finally,the simulation results verify the effectiveness and practicability of the proposed control strategy.
基金supported by the grants from National Natural Science Foundation of China(Nos.81820108020 and 81672143)Shanghai Pujiang Program(No.2020PJD039)the fund from China Scholarship Council.
文摘As the crucial powerhouse for cell metabolism and tissue survival,the mitochondrion frequently undergoes morphological or positional changes when responding to various stresses and energy demands.In addition to intracellular changes,mitochondria can also be transferred intercellularly.Besides restoring stressed cells and damaged tissues due to mitochondrial dysfunction,the intercellular mitochondrial transfer also occurs under physiological conditions.In this review,the phenomenon of mitochondrial transfer is described according to its function under both physiological and pathological conditions,including tissue homeostasis,damaged tissue repair,tumor progression,and immunoregulation.Then,the mechanisms that contribute to this process are summarized,such as the trigger factors and transfer routes.Furthermore,various perspectives are explored to better understand the mysteries of cell-cell mitochondrial trafficking.In addition,potential therapeutic strategies for mitochondria-targeted application to rescue tissue damage and degeneration,as well as the inhibition of tumor progression,are discussed.
基金supported by the National Key R&D Program of China(2016YFB0900603)the Technology Projects of State Grid Corporation of China(52094017000 W).
文摘For AC transmission lines connected to an LCC-HVDC inverter station,commutation failure can lead to the wrong operation of traditional protection.To solve the problem,this paper proposes a fast protection scheme using transient information from one end of the AC line.The boundary frequency characteristics of the AC line connected to LCC-HVDC inverter are analyzed first.This reveals the existence of significant attenuation on both high frequency signals and some specific frequency signals.Based on the boundary characteristics,a novel boundary protection principle utilizing a backward traveling wave is then proposed.A PSCAD/EMTDC simulation model of a±800 kV LCC-HVDC and 500 kV AC transmission system is established,and different fault cases are simulated.The simulation results prove that the novel protection principle is immune to commutation failure,fault resistance and fault type.
