The development of enantioselective C-H macrocyclizations to efficiently access structurally diversified macrocycles is highly desirable,but remain a big challenge.Herein,we reported the first rhodium(Ⅲ)-catalyzed as...The development of enantioselective C-H macrocyclizations to efficiently access structurally diversified macrocycles is highly desirable,but remain a big challenge.Herein,we reported the first rhodium(Ⅲ)-catalyzed asymmetric intramolecular C-H macrocyclization,enabling the efficient synthesis of structurally diverse enantioenriched macrocycles.This robust enantioselective C-H macrocyclization has a broad functional group tolerance,excellent enantioselectivities(up to 98.5:1.5 e.r.)and a mild reaction condition,releasing CO_(2)as the single by-product.More significantly,the resulting unique enantioenriched19-membered macrocycle 2f was found to demonstrate a potent in vitro anti-Zika virus(ZIKV)activity without obvious cytotoxicity.Further investigation revealed that the anti-ZIKV activity is presumably attributed to an autophagy inhibition in the early stage of viral infection by down-regulating the expression of autophagy related gene Atg12.展开更多
The multi-port energy router(ER)is an effective topology for integrating train traction load,AC load,the energy storage system and photovoltaic(PV)energy.The start and stop process of urban rail transit trains and the...The multi-port energy router(ER)is an effective topology for integrating train traction load,AC load,the energy storage system and photovoltaic(PV)energy.The start and stop process of urban rail transit trains and the access of distributed energy sources to rail transit ER lead to serious fluctuations of DC bus power,so it is necessary to route energy between different ports,involving multi-operating modes,while seamless switching is a major challenge.In this paper,a hierarchical coordinated control strategy is proposed to enable the multi-port ER to operate in a coor-dinated fashion under the conditions of train parking,acceleration,constant power driving and deceleration,and to switch seamlessly under various working conditions.The energy central dispatching layer sends working condi-tion instructions by sampling the state information of each port,while the microgrid control layer adopts central-ized control,receiving upper working condition instructions and sending drive signals to the local control layers to maintain the balanced energy flow of each port.In the local control layers,the PV adopts the improved perturbation and observation method of power control(PC-P&O),while the ES system adopts voltage loop control with an SOC influence factor,voltage loop control with switching factor and power loop control according to the different working conditions,so as to transmit the required train load power accurately and maintain the stability of the DC bus voltage.Finally,the effectiveness of the proposed hierarchical coordination control is verified by MATLAB/Simulink simulations.展开更多
Recombinant keratins possess strong hemostatic and wound healing properties but suffer from poor water solubility that restricts their bioactivities in biomedical applications.Herein,we report the rational design and ...Recombinant keratins possess strong hemostatic and wound healing properties but suffer from poor water solubility that restricts their bioactivities in biomedical applications.Herein,we report the rational design and synthesis of water-soluble keratins using a simple methodology named the QTY code.In vitro biophysical analyses and molecular dynamic simulation demonstrated a 200-fold increase in the water solubility of QTY variant keratins without apparent structural changes compared to native proteins.Homotypic self-assembly was observed for the first time in recombinant keratins in an aqueous environment,without urea and after QTY modification.Cell and animal experiments showed the in situ gel-forming capability of QTY variant keratins with superior hemostatic and wound healing activities at the wound sites compared to native recombinant keratins.Our work not only presented a simple and feasible pathway to produce large amounts of water-soluble keratins using QTY modification but also validated the enhanced self-assembly,hemostasis,and wound healing properties of these novel keratin species that may open up new venues for biomedical applications.展开更多
基金supported by National Natural Science Foundation of China(No.81973166)Science and Technology Commission of Shanghai Municipality(No.22XD1424600)+4 种基金Natural Science Foundation of Shanghai Municipality(No.22ZR1474100)Taishan Scholar Foundation of Shandong Province(No.tsqn202306322)National Key R&D Program of China(No.2021YFC2300700)Shandong Laboratory Program(No.SYS202205)Shandong Provincial Natural Science Foundation(Nos.ZR2023LSW003 and ZR2023JQ028)。
文摘The development of enantioselective C-H macrocyclizations to efficiently access structurally diversified macrocycles is highly desirable,but remain a big challenge.Herein,we reported the first rhodium(Ⅲ)-catalyzed asymmetric intramolecular C-H macrocyclization,enabling the efficient synthesis of structurally diverse enantioenriched macrocycles.This robust enantioselective C-H macrocyclization has a broad functional group tolerance,excellent enantioselectivities(up to 98.5:1.5 e.r.)and a mild reaction condition,releasing CO_(2)as the single by-product.More significantly,the resulting unique enantioenriched19-membered macrocycle 2f was found to demonstrate a potent in vitro anti-Zika virus(ZIKV)activity without obvious cytotoxicity.Further investigation revealed that the anti-ZIKV activity is presumably attributed to an autophagy inhibition in the early stage of viral infection by down-regulating the expression of autophagy related gene Atg12.
基金supported by the Chinese National Natural Science Foundation (grant number 51977039 and 51950410593).
文摘The multi-port energy router(ER)is an effective topology for integrating train traction load,AC load,the energy storage system and photovoltaic(PV)energy.The start and stop process of urban rail transit trains and the access of distributed energy sources to rail transit ER lead to serious fluctuations of DC bus power,so it is necessary to route energy between different ports,involving multi-operating modes,while seamless switching is a major challenge.In this paper,a hierarchical coordinated control strategy is proposed to enable the multi-port ER to operate in a coor-dinated fashion under the conditions of train parking,acceleration,constant power driving and deceleration,and to switch seamlessly under various working conditions.The energy central dispatching layer sends working condi-tion instructions by sampling the state information of each port,while the microgrid control layer adopts central-ized control,receiving upper working condition instructions and sending drive signals to the local control layers to maintain the balanced energy flow of each port.In the local control layers,the PV adopts the improved perturbation and observation method of power control(PC-P&O),while the ES system adopts voltage loop control with an SOC influence factor,voltage loop control with switching factor and power loop control according to the different working conditions,so as to transmit the required train load power accurately and maintain the stability of the DC bus voltage.Finally,the effectiveness of the proposed hierarchical coordination control is verified by MATLAB/Simulink simulations.
基金National Natural Science Foundation of China,Grant/Award Numbers:11972099,82202340Venture&Innovation Support Program for Chongqing Overseas Returnees,Grant/Award Number:cx2020079Scientific and Fundamental Research Funds for the Central Universities,Grant/Award Numbers:2023CDJXY-050,2023CDJXY-051。
文摘Recombinant keratins possess strong hemostatic and wound healing properties but suffer from poor water solubility that restricts their bioactivities in biomedical applications.Herein,we report the rational design and synthesis of water-soluble keratins using a simple methodology named the QTY code.In vitro biophysical analyses and molecular dynamic simulation demonstrated a 200-fold increase in the water solubility of QTY variant keratins without apparent structural changes compared to native proteins.Homotypic self-assembly was observed for the first time in recombinant keratins in an aqueous environment,without urea and after QTY modification.Cell and animal experiments showed the in situ gel-forming capability of QTY variant keratins with superior hemostatic and wound healing activities at the wound sites compared to native recombinant keratins.Our work not only presented a simple and feasible pathway to produce large amounts of water-soluble keratins using QTY modification but also validated the enhanced self-assembly,hemostasis,and wound healing properties of these novel keratin species that may open up new venues for biomedical applications.
