The use of traditional chemical catalysis to produce chemicals has a series of drawbacks,such as high dependence on fossil resources,high energy consumption,and environmental pollution.With the development of syntheti...The use of traditional chemical catalysis to produce chemicals has a series of drawbacks,such as high dependence on fossil resources,high energy consumption,and environmental pollution.With the development of synthetic biology and metabolic engineering,the use of renewable biomass raw materials for chemicals synthesis by constructing efficient microbial cell factories is a green way to replace traditional chemical catalysis and traditional microbial fermentation.This review mainly summarizes several types of bulk chemicals and high value-added chemicals using metabolic engineering and synthetic biology strategies to achieve efficient microbial production.In addition,this review also summarizes several strategies for effectively regulating microbial cell metabolism.These strategies can achieve the coupling balance of material and energy by regulating intracellular material metabolism or energy metabolism,and promote the efficient production of target chemicals by microorganisms.展开更多
Recognizing target intent is crucial for making decisions on the battlefield.However,the imperfect and ambiguous character of battlefield situations challenges the validity and causation analysis of classical intent r...Recognizing target intent is crucial for making decisions on the battlefield.However,the imperfect and ambiguous character of battlefield situations challenges the validity and causation analysis of classical intent recognition techniques.Facing with the challenge,a target intention causal analysis paradigm is proposed by combining with an Intervention Retrieval(IR)model and a Hybrid Intention Recognition(HIR)model.The target data acquired by the sensors are modelled as Basic Probability Assignments(BPAs)based on evidence theory to create uncertain datasets.Then,the HIR model is utilized to recognize intent for a tested sample from uncertain datasets.Finally,the intervention operator under the evidence structure is utilized to perform attribute intervention on the tested sample.Data retrieval is performed in the sample database based on the IR model to generate the intention distribution of the pseudo-intervention samples to analyze the causal effects of individual sample attributes.The simulation results demonstrate that our framework successfully identifies the target intention under the evidence structure and goes further to analyze the causal impact of sample attributes on the target intention.展开更多
Solid-state hydrogen storage tanks are key equipment for fuel cell vehicles and hydrogen storage.How-ever,the low heat transfer properties of hydrogen storage tanks result in the inability to meet the hy-drogen supply...Solid-state hydrogen storage tanks are key equipment for fuel cell vehicles and hydrogen storage.How-ever,the low heat transfer properties of hydrogen storage tanks result in the inability to meet the hy-drogen supply requirements of fuel cells.In this study,different thermal management approaches were explored through the design of LaNi5-based solid-state hydrogen storage tanks.We experimentally stud-ied the effects of different internal heat transfer methods,that is,expanded natural graphite(ENG),cop-per foam,and copper fins on the hydrogen absorption and desorption performance.We also studied the effects of external cooling methods with natural convection,air cooling,and water cooling,respectively.Under the same external cooling method of natural convection,a solid hydrogen storage tank filled with 5 wt.%ENG has similar performance to a tank filled with copper foam.Compared to natural convection,air and water cooling can significantly improve the heating performance of metal hydride(MH)beds by increasing the external heat transfer coefficient.The effect of water cooling is better than that of air cool-ing,and in these two enhanced performance conditions,the tank filled with copper foam performs better than with ENG.In the case of water cooling,by adding copper fins to a hydrogen storage tank filled with 5 wt.%ENG,the tank was saturated with hydrogen absorption in only 29.4 min,which is 55.6%shorter than the hydrogen uptake time in a hydrogen storage reactor without copper fins.And its stable hydrogen desorption(1 NL/min)has reached 98.1%of the total hydrogen released.The results show that the effec-tive thermal conductivity and heat transfer area of metal hydride bed play key roles in improving heat transfer and reaction rate.In addition,heat transfer is more important than mass transfer to improve the performance of the hydrogen storage tank.展开更多
Palladium-catalyzed asymmetric allylic C-H functionalization is an efficient method for the construction of enantiomerically enriched allylic derivatives.This includes asymmetric allylic amination reactions for the ef...Palladium-catalyzed asymmetric allylic C-H functionalization is an efficient method for the construction of enantiomerically enriched allylic derivatives.This includes asymmetric allylic amination reactions for the efficient construction of chiral amines.However,the asymmetric allylic C-H amination of alkenes by Lewis basic amines is a longstanding challenge.Herein,we present a highly efficient method for the palladium-catalyzed asymmetric intramolecular allylic C-H amination reaction.This method provides a means for synthesizing a range of biologically important enantioenriched isoindolines with high yields and excellent enantioselectivities(up to 98%yield and 98%ee).展开更多
Transcription factors(TFs)play vital roles in regulating gene expressions.Dysregulated or mutated TFs are implicated in a wide array of diseases,highlighting their potential as drug targets.However,TFs are considered ...Transcription factors(TFs)play vital roles in regulating gene expressions.Dysregulated or mutated TFs are implicated in a wide array of diseases,highlighting their potential as drug targets.However,TFs are considered undruggable by conventional inhibitor-based modalities.The recently emerged proteolysis targeting chimeras(PROTACs)have exhibited great potential in tackling TFs.In particular,DNA-ligand chimeras that arm E3 ligase-recruiting ligands to TF-binding double-strand DNA represent a promising strategy for the targeted proteolysis of TFs.Here,we report a DNAzyme-inducible PROTAC(DzTAC)that selectively degrades NF-κB in a zinc ion-dependent manner.We further applied zinc-imidazolate metal–organic framework90(ZIF-90)to encapsulate DzTAC(ZIF-90@DzTAC),facilitating its delivery into cancer cells while self-supplying Zn2+via adenosine triphosphate(ATP)-triggered ZIF-90 dissociation.Moreover,ZIF-90@DzTAC can enhance the treatment efficacy of doxorubicin-based chemotherapy in tumor-bearing mice.The developed DzTAC provides specific modulation over TF activity and opens an avenue for more functional nucleic acid-based control over targeted protein degradation.展开更多
Current Conditional Functional Dependency(CFD)discovery algorithms always need a well-prepared training dataset.This condition makes them difficult to apply on large and low-quality datasets.To handle the volume issue...Current Conditional Functional Dependency(CFD)discovery algorithms always need a well-prepared training dataset.This condition makes them difficult to apply on large and low-quality datasets.To handle the volume issue of big data,we develop the sampling algorithms to obtain a small representative training set.We design the fault-tolerant rule discovery and conflict-resolution algorithms to address the low-quality issue of big data.We also propose parameter selection strategy to ensure the effectiveness of CFD discovery algorithms.Experimental results demonstrate that our method can discover effective CFD rules on billion-tuple data within a reasonable period.展开更多
基金This work was financially supported by the National Natural Science Foundation of China(Grant Nos.21811530003,21861132017,U1663227,21706006)。
文摘The use of traditional chemical catalysis to produce chemicals has a series of drawbacks,such as high dependence on fossil resources,high energy consumption,and environmental pollution.With the development of synthetic biology and metabolic engineering,the use of renewable biomass raw materials for chemicals synthesis by constructing efficient microbial cell factories is a green way to replace traditional chemical catalysis and traditional microbial fermentation.This review mainly summarizes several types of bulk chemicals and high value-added chemicals using metabolic engineering and synthetic biology strategies to achieve efficient microbial production.In addition,this review also summarizes several strategies for effectively regulating microbial cell metabolism.These strategies can achieve the coupling balance of material and energy by regulating intracellular material metabolism or energy metabolism,and promote the efficient production of target chemicals by microorganisms.
基金partially supported by the National Natural Science Foundation of China(No.62173272)。
文摘Recognizing target intent is crucial for making decisions on the battlefield.However,the imperfect and ambiguous character of battlefield situations challenges the validity and causation analysis of classical intent recognition techniques.Facing with the challenge,a target intention causal analysis paradigm is proposed by combining with an Intervention Retrieval(IR)model and a Hybrid Intention Recognition(HIR)model.The target data acquired by the sensors are modelled as Basic Probability Assignments(BPAs)based on evidence theory to create uncertain datasets.Then,the HIR model is utilized to recognize intent for a tested sample from uncertain datasets.Finally,the intervention operator under the evidence structure is utilized to perform attribute intervention on the tested sample.Data retrieval is performed in the sample database based on the IR model to generate the intention distribution of the pseudo-intervention samples to analyze the causal effects of individual sample attributes.The simulation results demonstrate that our framework successfully identifies the target intention under the evidence structure and goes further to analyze the causal impact of sample attributes on the target intention.
基金supported by the National Key R&D Program of China(No.2022YFB3504701),the Open Project and Independent Research Project of State Key Laboratory of Advanced Spe-cial Steel,Shanghai Key Laboratory of Advanced Ferrometallurgy,Shanghai University(SKLASS 2023-01,SKLASS 2023-Z02)the Science and Technology Commission of Shanghai Municipality(No.20511107700).
文摘Solid-state hydrogen storage tanks are key equipment for fuel cell vehicles and hydrogen storage.How-ever,the low heat transfer properties of hydrogen storage tanks result in the inability to meet the hy-drogen supply requirements of fuel cells.In this study,different thermal management approaches were explored through the design of LaNi5-based solid-state hydrogen storage tanks.We experimentally stud-ied the effects of different internal heat transfer methods,that is,expanded natural graphite(ENG),cop-per foam,and copper fins on the hydrogen absorption and desorption performance.We also studied the effects of external cooling methods with natural convection,air cooling,and water cooling,respectively.Under the same external cooling method of natural convection,a solid hydrogen storage tank filled with 5 wt.%ENG has similar performance to a tank filled with copper foam.Compared to natural convection,air and water cooling can significantly improve the heating performance of metal hydride(MH)beds by increasing the external heat transfer coefficient.The effect of water cooling is better than that of air cool-ing,and in these two enhanced performance conditions,the tank filled with copper foam performs better than with ENG.In the case of water cooling,by adding copper fins to a hydrogen storage tank filled with 5 wt.%ENG,the tank was saturated with hydrogen absorption in only 29.4 min,which is 55.6%shorter than the hydrogen uptake time in a hydrogen storage reactor without copper fins.And its stable hydrogen desorption(1 NL/min)has reached 98.1%of the total hydrogen released.The results show that the effec-tive thermal conductivity and heat transfer area of metal hydride bed play key roles in improving heat transfer and reaction rate.In addition,heat transfer is more important than mass transfer to improve the performance of the hydrogen storage tank.
基金support was provided by the State Key Laboratory of Pulp and Paper Engineering,China(grant no.2022PY01)the National Natural Science Foundation of China(grant nos.22231002 and 21871095)the KeyArea Research and Development Program of Guangdong Province,China(grant no.2020B010188001)。
文摘Palladium-catalyzed asymmetric allylic C-H functionalization is an efficient method for the construction of enantiomerically enriched allylic derivatives.This includes asymmetric allylic amination reactions for the efficient construction of chiral amines.However,the asymmetric allylic C-H amination of alkenes by Lewis basic amines is a longstanding challenge.Herein,we present a highly efficient method for the palladium-catalyzed asymmetric intramolecular allylic C-H amination reaction.This method provides a means for synthesizing a range of biologically important enantioenriched isoindolines with high yields and excellent enantioselectivities(up to 98%yield and 98%ee).
基金supported by the National Natural Science Foundation of China(NSFC)Programs(22204046)the Hunan Science Fund for Excellent Young Scholars(2023JJ20002)+2 种基金the National Key Research Program(2019YFA0905800)the Changsha Municipal Natural Science Foundation(kq2402088)the Scientific Research Fund of Hunan Provincial Education Department(22B0874,23B0844).
文摘Transcription factors(TFs)play vital roles in regulating gene expressions.Dysregulated or mutated TFs are implicated in a wide array of diseases,highlighting their potential as drug targets.However,TFs are considered undruggable by conventional inhibitor-based modalities.The recently emerged proteolysis targeting chimeras(PROTACs)have exhibited great potential in tackling TFs.In particular,DNA-ligand chimeras that arm E3 ligase-recruiting ligands to TF-binding double-strand DNA represent a promising strategy for the targeted proteolysis of TFs.Here,we report a DNAzyme-inducible PROTAC(DzTAC)that selectively degrades NF-κB in a zinc ion-dependent manner.We further applied zinc-imidazolate metal–organic framework90(ZIF-90)to encapsulate DzTAC(ZIF-90@DzTAC),facilitating its delivery into cancer cells while self-supplying Zn2+via adenosine triphosphate(ATP)-triggered ZIF-90 dissociation.Moreover,ZIF-90@DzTAC can enhance the treatment efficacy of doxorubicin-based chemotherapy in tumor-bearing mice.The developed DzTAC provides specific modulation over TF activity and opens an avenue for more functional nucleic acid-based control over targeted protein degradation.
基金partially supported by the National Key R&D Program of China(No.2018YFB1004700)the National Natural Science Foundation of China(Nos.U1509216,U1866602,and 61602129)Microsoft Research Asia.
文摘Current Conditional Functional Dependency(CFD)discovery algorithms always need a well-prepared training dataset.This condition makes them difficult to apply on large and low-quality datasets.To handle the volume issue of big data,we develop the sampling algorithms to obtain a small representative training set.We design the fault-tolerant rule discovery and conflict-resolution algorithms to address the low-quality issue of big data.We also propose parameter selection strategy to ensure the effectiveness of CFD discovery algorithms.Experimental results demonstrate that our method can discover effective CFD rules on billion-tuple data within a reasonable period.
