Integrated water and fertilizer management is important for promoting sustainable development of facility agriculture,and biochar plays an important role in guaranteeing food production,as well as alleviating water sh...Integrated water and fertilizer management is important for promoting sustainable development of facility agriculture,and biochar plays an important role in guaranteeing food production,as well as alleviating water shortages and the overuse of fertilizers.The field experiment had twelve treatments and a control(CK)trial including two irrigation amounts(I1,100%ETm;I2,60%ETm;where ETm is the maximum evapotranspiration),two nitrogen applications(N1,360 kg ha^(−1);N2,120 kg ha^(−1))and three biochar application levels(B1,60 t ha^(−1);B_(2),30 t ha^(−1)and B3,0 t ha^(−1)).A multi-objective synergistic irrigation-nitrogen-biochar application system for improving tomato yield,quality,water and nitrogen use efficiency,and greenhouse emissions was developed by integrating the techniques of experimentation and optimization.First,a coupled irrigation-nitrogen-biochar plot experiment was arranged.Then,tomato yield and fruit quality parameters were determined experimentally to establish the response relationships between irrigation-nitrogen-biochar dosage and yield,comprehensive quality of tomatoes(TCQ),irrigation water use efficiency(IWUE),partial factor productivity of nitrogen(PFPN),and net greenhouse gas emissions(NGE).Finally,a multi-objective dynamic optimization regulation model of irrigation-nitrogen-biochar resource allocation at different growth stages of tomato was constructed which was solved by the fuzzy programming method.The results showed that the application of irrigation and nitrogen to biochar promoted increase in yield,IWUE and PFPN,while it had an inhibitory effect on NGE.In addition,the optimal allocation amounts of water and fertilizer were different under different scenarios.The yield of the S1 scenario increased by 8.31%compared to the B_(1)I_(1)N_(2) treatment;TCQ of the S2 scenario increased by 5.14%compared to the B_(2)I_(2)N_(1) treatment;IWUE of the S3 scenario increased by 10.01%compared to the B1I2N2 treatment;PFPN of the S4 scenario increased by 9.35%compared to the B_(1)I_(1)N_(2) treatment;and NGE of the S5 scenario decreased by 11.23%compared to the B_(2)I1N1 treatment.The optimization model showed that the coordination of multiple objectives considering yield,TCQ,IWUE,PFPN,and NGE increased on average from 4.44 to 69.02%compared to each treatment when the irrigation-nitrogen-biochar dosage was 205.18 mm,186 kg ha^(−1)and 43.31 t ha^(−1),respectively.This study provides a guiding basis for the sustainable management of water and fertilizer in greenhouse tomato production under drip irrigation fertilization conditions.展开更多
Pipeline isolation plugging robot (PIPR) is an important tool in pipeline maintenance operation. During the plugging process, the violent vibration will occur by the flow field, which can cause serious damage to the p...Pipeline isolation plugging robot (PIPR) is an important tool in pipeline maintenance operation. During the plugging process, the violent vibration will occur by the flow field, which can cause serious damage to the pipeline and PIPR. In this paper, we propose a dynamic regulating strategy to reduce the plugging-induced vibration by regulating the spoiler angle and plugging velocity. Firstly, the dynamic plugging simulation and experiment are performed to study the flow field changes during dynamic plugging. And the pressure difference is proposed to evaluate the degree of flow field vibration. Secondly, the mathematical models of pressure difference with plugging states and spoiler angles are established based on the extreme learning machine (ELM) optimized by improved sparrow search algorithm (ISSA). Finally, a modified Q-learning algorithm based on simulated annealing is applied to determine the optimal strategy for the spoiler angle and plugging velocity in real time. The results show that the proposed method can reduce the plugging-induced vibration by 19.9% and 32.7% on average, compared with single-regulating methods. This study can effectively ensure the stability of the plugging process.展开更多
How to control the dynamic behavior of large-scale artificial active matter is a critical concern in experimental research on soft matter, particularly regarding the emergence of collective behaviors and the formation...How to control the dynamic behavior of large-scale artificial active matter is a critical concern in experimental research on soft matter, particularly regarding the emergence of collective behaviors and the formation of group patterns. Centralized systems excel in precise control over individual behavior within a group, ensuring high accuracy and controllability in task execution. Nevertheless, their sensitivity to group size may limit their adaptability to diverse tasks. In contrast, decentralized systems empower individuals with autonomous decision-making, enhancing adaptability and system robustness. Yet, this flexibility comes at the cost of reduced accuracy and efficiency in task execution. In this work, we present a unique method for regulating the centralized dynamic behavior of self-organizing clusters based on environmental interactions. Within this environment-coupled robot system, each robot possesses similar dynamic characteristics, and their internal programs are entirely identical. However, their behaviors can be guided by the centralized control of the environment, facilitating the accomplishment of diverse cluster tasks. This approach aims to balance the accuracy and flexibility of centralized control with the robustness and task adaptability of decentralized control. The proactive regulation of dynamic behavioral characteristics in active matter groups, demonstrated in this work through environmental interactions, holds the potential to introduce a novel technological approach and provide experimental references for studying the dynamic behavior control of large-scale artificial active matter systems.展开更多
Nowadays,the microgrid cluster is an important application scenario for energy trading.In trading,one of the most important research directions is the issue of pricing.To determine reasonable pricing for the microgrid...Nowadays,the microgrid cluster is an important application scenario for energy trading.In trading,one of the most important research directions is the issue of pricing.To determine reasonable pricing for the microgrid cluster,data communication is used to create the cyber-physical system(CPS),which can improve the observability of microgrids.Then,the following works are carried out in the CPS.In the physical layer:1)Regarding trading between microgrids and the load,based on the generalized game theory,an optimal pricing strategy is proposed,which takes into account the interactive relationships among microgrids and transforms the pricing problem into a Nikaido-Isoda function to obtain the optimal prices conveniently;2)Regarding peer-to-peer trading between two microgrids,based on evolutionary game theory and the penalty mechanism,the optimal sale price of the seller is selected with boundary rationality.In the cyber layer,regarding the communication interruption issue existing in pricing(i.e.,the game process),based on the principle of matching the performance of the path with the importance degree of the data,a dynamic regulating method of paths is proposed,i.e.,adopting a new path to re-transmit the interrupted data to the destination.Finally,the effect of the proposed strategies is verified by case studies.展开更多
Control strategy affects directly the working performances of dynamic voltage regulator (DVR). One-cycle control is an effective nonlinear signal modulation control method. In this paper, a new one-cycle control sch...Control strategy affects directly the working performances of dynamic voltage regulator (DVR). One-cycle control is an effective nonlinear signal modulation control method. In this paper, a new one-cycle control scheme for DVR was proposed in single phase supply system. On the basis of principle analysis, the corresponding one-cycle control model for DVR was built up, which is characterized by simple control circuits, good control performance, and high control precision. As an example, a control model for single-phase DVR was simulated by using Matlab/Simulink and SimPowerSystem. The results show that the load voltage could be compensated quickly at the points of supply voltage stepping down and up, and the relative error was less than 4% in the whole voltage sag process. Both theory analysis and simulation results show that the new one-cycle control scheme for DVR is effective.展开更多
Stem cells possess the ability to divide symmetrically or asymmet- rically to allow for maintenance of the stem cell pool or become committed progenitors and differentiate into various cell lineages. The unique self-r...Stem cells possess the ability to divide symmetrically or asymmet- rically to allow for maintenance of the stem cell pool or become committed progenitors and differentiate into various cell lineages. The unique self-renewal capabilities and pluripotency of stem cells are integral to tissue regeneration and repair (Oh et al., 2014). Mul- tiple mechanisms including intracellular programs and extrinsic cues are reported to regulate neural stem cell (NSC) fate (Bond et al., 2015). A recent study, published in Cell Stern Cell, identified a novel mechanism whereby mitochondrial dynamics drive NSC fate (Khacho et al., 2016).展开更多
Phenolic compounds(PCs)are a group of compounds with various applications in nutraceutical,pharmaceutical and cosmetic industries.Their supply by plant extraction and chemical synthesis is often limited by low yield a...Phenolic compounds(PCs)are a group of compounds with various applications in nutraceutical,pharmaceutical and cosmetic industries.Their supply by plant extraction and chemical synthesis is often limited by low yield and high cost.Microbial production represents as a promising alternative for efficient and sustainable production of PCs.In this review,we summarize recent advances in this field,which include enzyme mining and engineering to construct artificial pathways,balance of enzyme expression to improve pathway efficiency,coculture engineering to alleviate metabolic burden and side-reactions,and the use of genetic circuits for dynamic regulation and high throughput screening.Finally,current challenges and future perspectives for efficient production of PCs are also discussed.展开更多
Titanium(Ti)and its alloys have been widely used as orthopedic implants,because of their favorable mechanical properties,corrosion resistance and biocompatibility.Despite their significant success in various clinical ...Titanium(Ti)and its alloys have been widely used as orthopedic implants,because of their favorable mechanical properties,corrosion resistance and biocompatibility.Despite their significant success in various clinical applications,the probability of failure,degradation and revision is undesirably high,especially for the patients with low bone density,insufficient quantity of bone or osteoporosis,which renders the studies on surface modification of Ti still active to further improve clinical results.It is discerned that surface physicochemical properties directly influence and even control the dynamic interaction that subsequently determines the success or rejection of orthopedic implants.Therefore,it is crucial to endow bulk materials with specific surface properties of high bioactivity that can be performed by surface modification to realize the osseointegration.This article first reviews surface characteristics of Ti materials and various conventional surface modification techniques involving mechanical,physical and chemical treatments based on the formation mechanism of the modified coatings.Such conventional methods are able to improve bioactivity of Ti implants,but the surfaces with static state cannot respond to the dynamic biological cascades from the living cells and tissues.Hence,beyond traditional static design,dynamic responsive avenues are then emerging.The dynamic stimuli sources for surface functionalization can originate from environmental triggers or physiological triggers.In short,this review surveys recent developments in the surface engineering of Ti materials,with a specific emphasis on advances in static to dynamic functionality,which provides perspectives for improving bioactivity and biocompatibility of Ti implants.展开更多
Advances in plant phenotyping technologies are dramatically reducing the marginal costs of collecting multiple phenotypic measurements across several time points.Yet,most current approaches and best statistical practi...Advances in plant phenotyping technologies are dramatically reducing the marginal costs of collecting multiple phenotypic measurements across several time points.Yet,most current approaches and best statistical practices implemented to link genetic and phenotypic variation in plants have been developed in an era of single-time-point data.Here,we used time-series phenotypic data collected with an unmanned aircraft system for a large panel of soybean(Glycine max(L.)Merr.)varieties to identify previously uncharacterized loci.Specifically,we focused on the dissection of canopy coverage(CC)variation from this rich data set.We also inferred the speed of canopy closure,an additional dimension of CC,from the time-series data,as it may represent an important trait for weed control.Genome-wide association studies(GWASs)identified 35 loci exhibiting dynamic associations with CC across developmental stages.The time-series data enabled the identification of 10 known flowering time and plant height quantitative trait loci(QTLs)detected in previous studies of adult plants and the identification of novel QTLs influencing CC.These novel QTLs were disproportionately likely to act earlier in development,which may explain why they were missed in previous single-time-point studies.Moreover,this time-series data set contributed to the high accuracy of the GWASs,which we evaluated by permutation tests,as evidenced by the repeated identification of loci across multiple time points.Two novel loci showed evidence of adaptive selection during domestication,with different genotypes/haplotypes favored in different geographic regions.In summary,the time-series data,with soybean CC as an example,improved the accuracy and statistical power to dissect the genetic basis of traits and offered a promising opportunity for crop breeding with quantitative growth curves.展开更多
The continuous development of hydrogen-electrolyser and fuel-cell technologies not only reduces their investment and operating costs but also improves their technical performance to meet fast-acting requirements of el...The continuous development of hydrogen-electrolyser and fuel-cell technologies not only reduces their investment and operating costs but also improves their technical performance to meet fast-acting requirements of electrical grid balancing services such as frequency-response services.In order to project the feasibility of co-locating a hydrogen-storage system with a wind farm for the dynamic regulation frequency-response provision in Great Britain,this paper develops a modelling framework to coordinate the wind export and frequency responses to the main grid and manage the interaction of the electrolyser,compressor,storage tank and fuel cell within the hydrogen-storage system by respecting the market mechanisms and the balance and conversion of power and hydrogen flows.Then the revenue of frequency-response service provision and a variety of costs induced by the hydrogen-storage system are translated into the net profit of the co-location system,which is maximized by optimizing the capacities of hydrogen-storage-system components,hydrogen-storage levels that guide the hydrogen restoration via operational baselines and the power interchange between a wind-farm and hydrogen-storage system,as well as the capacities tendered for low-and high-frequency dynamic regulation services.The developed modelling framework is tested based on a particular 432-MW offshore wind farm in Great Britain combined with the techno-economics of electrolysers and fuel cells projected for 2030 and 2050 scenarios.The optimized system configuration and operation are compared between different operating scenarios and discussed alongside the prospect of applying hydrogen-storage systems for frequency-response provision.展开更多
The mucosal immune system is considered a local immune system,a term that implies regional restriction.Mucosal tissues are continually exposed to a wide range of antigens.The regulation of mucosal immune cells is tigh...The mucosal immune system is considered a local immune system,a term that implies regional restriction.Mucosal tissues are continually exposed to a wide range of antigens.The regulation of mucosal immune cells is tightly associated with the progression of mucosal diseases.Innate lymphoid cells(ILCs)are abundant in mucosal barriers and serve as first-line defenses against pathogens.The subtype changes and translocation of ILCs are accompanied by the pathologic processes of mucosal diseases.Here,we review the plasticity and circulation of ILCs in the mucosal immune system under physiological and pathological conditions.We also discuss the signaling pathways involved in dynamic ILC changes and the related targets in mucosal diseases.展开更多
Succinate is an important building block for chemical synthesis.However,during the fermentation process,excessive osmotic stress and byproduct accumulation substantively impair the performance of the microbial cell fa...Succinate is an important building block for chemical synthesis.However,during the fermentation process,excessive osmotic stress and byproduct accumulation substantively impair the performance of the microbial cell factory.To this end,two strategies were proposed.First,an osmo-tolerant mutant,Escherichia coli FMME-N-2,was screened by combined mutagenesis(ARTP and^(60)Co-γirradiation)to produce 51.8 g L^(−1)succinate with a productivity of 0.81 g L^(−1)h^(−1).Second,an oxygen-dependent bifunctional switch(OBS)was developed with promoter PfnrF8-based activation and tobacco etch virus protease-based inhibition functions.With ribosomal binding site(RBS)and degron optimization of OBS,the optimal strain E.coli FMME-N-30 achieved a succinate titer and productivity of 119 g L^(−1)and 1.65 g L^(−1) h^(−1),respectively,in a 30-L fermentor,while only 7.1 g L^(−1)acetate and no formate or lactate were detected.Compared to the wild-type strain E.coli FMME-N,the succinate titer was increased by 3.3-fold.These results highlight the applicability of OBS for the large-scale production of value-added chemicals.展开更多
Itaconic acid(ITA),an effective alternative fossil fuel,derives from the bypass pathway of the tricarboxylic acid(TCA)cycle.Therefore,the imbalance of metabolic flux between TCA cycle and ITA biosynthetic pathway seri...Itaconic acid(ITA),an effective alternative fossil fuel,derives from the bypass pathway of the tricarboxylic acid(TCA)cycle.Therefore,the imbalance of metabolic flux between TCA cycle and ITA biosynthetic pathway seriously limits the production of ITA.The optimization of flux distribution between biomass and production has the potential to the productivity of ITA.Based on the previously constructed strain Escherichia coli MG1655Δ1-SAS-3(ITA titer:1.87 g/L),a CRISPRi-mediated self-inducible system(CiMS),which contained a responsive module based on the ITA biosensor YpItcR/Pccl and a regulative CRISPRi-mediated interferential module,was developed to regulate the flux of the TCA cycle and to enhance the capacity of the strain to produce ITA.First,a higher ITA-yielding strain,Δ4-Prmd-SAS-3(ITA titer:3.20 g/L),derived fromΔ1-SAS-3,was constructed by replacing the promoter PJ23100,for the expression of ITA synthesis genes,with Prmd and knocking out the three bypass genes poxB,pflB,and ldhA.Subsequently,the CiMS was used to inhibit the expression of key genes icd,pykA,and sucCD to dynamically balance the metabolic flux between TCA cycle and ITA biosynthetic pathway during the ITA production stage.The constructed strainΔ4-Prmd-SAS-3 under the dynamic regulation of the CiMS,showed a 23%increase in the ITA titer,which reached 3.93 g/L.This study indicated that CiMS was a practical strategy to dynamically and precisely regulated the metabolic flux in microbial cell factories.展开更多
Smart textiles are attracting great interest.Particularly,air-conditioning textiles are highly desired for their merits in energy conservation and personal temperature/humidity management.Currently,air-conditioning te...Smart textiles are attracting great interest.Particularly,air-conditioning textiles are highly desired for their merits in energy conservation and personal temperature/humidity management.Currently,air-conditioning textiles can be fabricated by two strategies.One uses infrared-radiation-adaptive materials,and the other uses moisture-responsive actuators that can regulate temperature and humidity simultaneously.Here,the fabrication of a silk-yarn switch comprising electrospun highly aligned nanofibers is reported and its application in air-conditioning textiles is demonstrated.Silk yarn rotates in contact with liquid,and can be recovered by drying.The different responses and wetting behaviors of the switch to H_(2)O and C_(2)H_(6)O is investigated.It is argued that alignment and surface hydrophilicity of nanofibers play important roles in this term.To elaborate,actuating trait is mainly controlled by reduction of the surface free energy of aligned silk nanofibers,during the wetting process.As proof of concept,the application of the sweat-driven silk-yarn switch in regulating the temperature/humidity of the human body is demonstrated in this work.Considering the large production,versatile processibility,and good biocompatibility,silk actuator may have practical applications in designing smart switches(or valves)for intelligent textiles,artificial muscles,and other application scenarios.展开更多
Syngas,which contains large amount of CO2 as well as H2 and CO,can be convert to acetic acid chemically or biologically.Nowadays,acetic acid become a cost-effective nonfood-based carbon source for value-added biochemi...Syngas,which contains large amount of CO2 as well as H2 and CO,can be convert to acetic acid chemically or biologically.Nowadays,acetic acid become a cost-effective nonfood-based carbon source for value-added biochemical production.In this study,acetic acid and CO2 were used as substrates for the biosynthesis of 3-hydroxypropionic acid(3-HP)in metabolically engineered Escherichia coli carrying heterogeneous acetyl-CoA carboxylase(Acc)from Corynebacterium glutamicum and codon-optimized malonyl-CoA reductase(MCR)from Chloroflexus aurantiacus.Strategies of metabolic engineering included promoting glyoxylate shunt pathway,inhibiting fatty acid synthesis,dynamic regulating of TCA cycle,and enhancing the assimilation of acetic acid.The engineered strain LNY07(M*DA)accumulated 15.8 g/L of 3-HP with the yield of 0.71 g/g in 48 h by whole-cell biocatalysis.Then,syngas-derived acetic acid was used as substrate instead of pure acetic acid.The concentration of 3-HP reached 11.2 g/L with the yield of 0.55 g/g in LNY07(M*DA).The results could potentially contribute to the future development of an industrial bioprocess of 3-HP production from syngas-derived acetic acid.展开更多
There are numerous microorganisms in nature capable of synthesizing diverse useful compounds;however,these natural microorganisms are generally inefficient in the production of target products on an industrial scale,r...There are numerous microorganisms in nature capable of synthesizing diverse useful compounds;however,these natural microorganisms are generally inefficient in the production of target products on an industrial scale,relative to either chemical synthesis or extraction methods.To achieve industrial production of useful compounds,these natural microorganisms must undergo a certain degree of mutation or effective fine-tuning strategies.This review describes how to achieve an ideal metabolic fine-tuned process,including static control strategies and dynamic control strategies.The static control strategies mainly focus on various matabolic engineering strategies,including protein engineering,upregulation/downregulation,and combinatrorial control of these metabolic engineering strategies,to enhance the flexibility of their application in fine-tuned metabolic metworks.Then,we focus on the dynamic control strategies for fine-tuned metabolic metworks.The design principles derived would guide us to construct microbial cell factories for various useful compounds.展开更多
基金supported by the National Natural Science Foundation of China(52222902 and 52079029)。
文摘Integrated water and fertilizer management is important for promoting sustainable development of facility agriculture,and biochar plays an important role in guaranteeing food production,as well as alleviating water shortages and the overuse of fertilizers.The field experiment had twelve treatments and a control(CK)trial including two irrigation amounts(I1,100%ETm;I2,60%ETm;where ETm is the maximum evapotranspiration),two nitrogen applications(N1,360 kg ha^(−1);N2,120 kg ha^(−1))and three biochar application levels(B1,60 t ha^(−1);B_(2),30 t ha^(−1)and B3,0 t ha^(−1)).A multi-objective synergistic irrigation-nitrogen-biochar application system for improving tomato yield,quality,water and nitrogen use efficiency,and greenhouse emissions was developed by integrating the techniques of experimentation and optimization.First,a coupled irrigation-nitrogen-biochar plot experiment was arranged.Then,tomato yield and fruit quality parameters were determined experimentally to establish the response relationships between irrigation-nitrogen-biochar dosage and yield,comprehensive quality of tomatoes(TCQ),irrigation water use efficiency(IWUE),partial factor productivity of nitrogen(PFPN),and net greenhouse gas emissions(NGE).Finally,a multi-objective dynamic optimization regulation model of irrigation-nitrogen-biochar resource allocation at different growth stages of tomato was constructed which was solved by the fuzzy programming method.The results showed that the application of irrigation and nitrogen to biochar promoted increase in yield,IWUE and PFPN,while it had an inhibitory effect on NGE.In addition,the optimal allocation amounts of water and fertilizer were different under different scenarios.The yield of the S1 scenario increased by 8.31%compared to the B_(1)I_(1)N_(2) treatment;TCQ of the S2 scenario increased by 5.14%compared to the B_(2)I_(2)N_(1) treatment;IWUE of the S3 scenario increased by 10.01%compared to the B1I2N2 treatment;PFPN of the S4 scenario increased by 9.35%compared to the B_(1)I_(1)N_(2) treatment;and NGE of the S5 scenario decreased by 11.23%compared to the B_(2)I1N1 treatment.The optimization model showed that the coordination of multiple objectives considering yield,TCQ,IWUE,PFPN,and NGE increased on average from 4.44 to 69.02%compared to each treatment when the irrigation-nitrogen-biochar dosage was 205.18 mm,186 kg ha^(−1)and 43.31 t ha^(−1),respectively.This study provides a guiding basis for the sustainable management of water and fertilizer in greenhouse tomato production under drip irrigation fertilization conditions.
基金This work was financially supported by the National Natural Science Foundation of China(Grant No.51575528)the Science Foundation of China University of Petroleum,Beijing(No.2462022QEDX011).
文摘Pipeline isolation plugging robot (PIPR) is an important tool in pipeline maintenance operation. During the plugging process, the violent vibration will occur by the flow field, which can cause serious damage to the pipeline and PIPR. In this paper, we propose a dynamic regulating strategy to reduce the plugging-induced vibration by regulating the spoiler angle and plugging velocity. Firstly, the dynamic plugging simulation and experiment are performed to study the flow field changes during dynamic plugging. And the pressure difference is proposed to evaluate the degree of flow field vibration. Secondly, the mathematical models of pressure difference with plugging states and spoiler angles are established based on the extreme learning machine (ELM) optimized by improved sparrow search algorithm (ISSA). Finally, a modified Q-learning algorithm based on simulated annealing is applied to determine the optimal strategy for the spoiler angle and plugging velocity in real time. The results show that the proposed method can reduce the plugging-induced vibration by 19.9% and 32.7% on average, compared with single-regulating methods. This study can effectively ensure the stability of the plugging process.
基金Project supported by the National Natural Science Foundation of China (Grant No. 12174041)China Postdoctoral Science Foundation (CPSF)(Grant No. 2022M723118)the seed grants from the Wenzhou Institute,University of Chinese Academy of Sciences (Grant No. WIUCASQD2021002)。
文摘How to control the dynamic behavior of large-scale artificial active matter is a critical concern in experimental research on soft matter, particularly regarding the emergence of collective behaviors and the formation of group patterns. Centralized systems excel in precise control over individual behavior within a group, ensuring high accuracy and controllability in task execution. Nevertheless, their sensitivity to group size may limit their adaptability to diverse tasks. In contrast, decentralized systems empower individuals with autonomous decision-making, enhancing adaptability and system robustness. Yet, this flexibility comes at the cost of reduced accuracy and efficiency in task execution. In this work, we present a unique method for regulating the centralized dynamic behavior of self-organizing clusters based on environmental interactions. Within this environment-coupled robot system, each robot possesses similar dynamic characteristics, and their internal programs are entirely identical. However, their behaviors can be guided by the centralized control of the environment, facilitating the accomplishment of diverse cluster tasks. This approach aims to balance the accuracy and flexibility of centralized control with the robustness and task adaptability of decentralized control. The proactive regulation of dynamic behavioral characteristics in active matter groups, demonstrated in this work through environmental interactions, holds the potential to introduce a novel technological approach and provide experimental references for studying the dynamic behavior control of large-scale artificial active matter systems.
基金This work was supported in part by the National Key Research and Development Program of China(2018YFA0702200)the National Natural Science Foundation of China(61933005,61833008)+6 种基金the Natural Science Foundation of Jiangsu Province of China(BK20220395)the Leading Technology Foundation Research Project of Jiangsu Province(BK20202011)the Natural Science Foundation of Jiangsu Universities(22KJB470024)Jiangsu Provincial Key Research and Development Program(BE2020001)Natural Science Foundation of Hebei Province of China(E2020203139)Natural Science Foundation of Nanjing University of Posts and Telecommunications(NY222032)the National Research Foundation of Korea(2020R1A2B5B02002002).
文摘Nowadays,the microgrid cluster is an important application scenario for energy trading.In trading,one of the most important research directions is the issue of pricing.To determine reasonable pricing for the microgrid cluster,data communication is used to create the cyber-physical system(CPS),which can improve the observability of microgrids.Then,the following works are carried out in the CPS.In the physical layer:1)Regarding trading between microgrids and the load,based on the generalized game theory,an optimal pricing strategy is proposed,which takes into account the interactive relationships among microgrids and transforms the pricing problem into a Nikaido-Isoda function to obtain the optimal prices conveniently;2)Regarding peer-to-peer trading between two microgrids,based on evolutionary game theory and the penalty mechanism,the optimal sale price of the seller is selected with boundary rationality.In the cyber layer,regarding the communication interruption issue existing in pricing(i.e.,the game process),based on the principle of matching the performance of the path with the importance degree of the data,a dynamic regulating method of paths is proposed,i.e.,adopting a new path to re-transmit the interrupted data to the destination.Finally,the effect of the proposed strategies is verified by case studies.
基金The National Science and Technology Sup-port Project (No.2007BAA12B03)
文摘Control strategy affects directly the working performances of dynamic voltage regulator (DVR). One-cycle control is an effective nonlinear signal modulation control method. In this paper, a new one-cycle control scheme for DVR was proposed in single phase supply system. On the basis of principle analysis, the corresponding one-cycle control model for DVR was built up, which is characterized by simple control circuits, good control performance, and high control precision. As an example, a control model for single-phase DVR was simulated by using Matlab/Simulink and SimPowerSystem. The results show that the load voltage could be compensated quickly at the points of supply voltage stepping down and up, and the relative error was less than 4% in the whole voltage sag process. Both theory analysis and simulation results show that the new one-cycle control scheme for DVR is effective.
基金AJ-A is a Fonds de recherche du Québec-Santé(FRQS)scholarsupported by a grant from Natural Sciences and Engineering Research Council of Canada(NSERC RGPIN-2016-06605)
文摘Stem cells possess the ability to divide symmetrically or asymmet- rically to allow for maintenance of the stem cell pool or become committed progenitors and differentiate into various cell lineages. The unique self-renewal capabilities and pluripotency of stem cells are integral to tissue regeneration and repair (Oh et al., 2014). Mul- tiple mechanisms including intracellular programs and extrinsic cues are reported to regulate neural stem cell (NSC) fate (Bond et al., 2015). A recent study, published in Cell Stern Cell, identified a novel mechanism whereby mitochondrial dynamics drive NSC fate (Khacho et al., 2016).
基金This work was supported by National Key Research and Development Program of China(2018YFA0901800 and 2018YFA0901400)National Natural Science Foundation of China(21978015,21636001,and 21776008).
文摘Phenolic compounds(PCs)are a group of compounds with various applications in nutraceutical,pharmaceutical and cosmetic industries.Their supply by plant extraction and chemical synthesis is often limited by low yield and high cost.Microbial production represents as a promising alternative for efficient and sustainable production of PCs.In this review,we summarize recent advances in this field,which include enzyme mining and engineering to construct artificial pathways,balance of enzyme expression to improve pathway efficiency,coculture engineering to alleviate metabolic burden and side-reactions,and the use of genetic circuits for dynamic regulation and high throughput screening.Finally,current challenges and future perspectives for efficient production of PCs are also discussed.
基金supported by National Key Research and Development Program of China(grant Nos.2020YFC2004900,2016YFC1100300)the National Natural Science Foundation of China(grant Nos.21773199,51571169,52001265).
文摘Titanium(Ti)and its alloys have been widely used as orthopedic implants,because of their favorable mechanical properties,corrosion resistance and biocompatibility.Despite their significant success in various clinical applications,the probability of failure,degradation and revision is undesirably high,especially for the patients with low bone density,insufficient quantity of bone or osteoporosis,which renders the studies on surface modification of Ti still active to further improve clinical results.It is discerned that surface physicochemical properties directly influence and even control the dynamic interaction that subsequently determines the success or rejection of orthopedic implants.Therefore,it is crucial to endow bulk materials with specific surface properties of high bioactivity that can be performed by surface modification to realize the osseointegration.This article first reviews surface characteristics of Ti materials and various conventional surface modification techniques involving mechanical,physical and chemical treatments based on the formation mechanism of the modified coatings.Such conventional methods are able to improve bioactivity of Ti implants,but the surfaces with static state cannot respond to the dynamic biological cascades from the living cells and tissues.Hence,beyond traditional static design,dynamic responsive avenues are then emerging.The dynamic stimuli sources for surface functionalization can originate from environmental triggers or physiological triggers.In short,this review surveys recent developments in the surface engineering of Ti materials,with a specific emphasis on advances in static to dynamic functionality,which provides perspectives for improving bioactivity and biocompatibility of Ti implants.
基金partially supported by the National Key R&D Program of China (2021YFD1201601)the Agricultural Science and Technology Innovation Program (ASTIP)of the Chinese Academy of Agricultural Sciences (CAAS-ZDRW202109)+1 种基金Hainan Yazhou Bay Seed Lab (B21HJ0221)supported by the UK Biotechnology and Biological Sciences Research Council as part of the Designing Future Wheat Project (BB/P016855/1)。
文摘Advances in plant phenotyping technologies are dramatically reducing the marginal costs of collecting multiple phenotypic measurements across several time points.Yet,most current approaches and best statistical practices implemented to link genetic and phenotypic variation in plants have been developed in an era of single-time-point data.Here,we used time-series phenotypic data collected with an unmanned aircraft system for a large panel of soybean(Glycine max(L.)Merr.)varieties to identify previously uncharacterized loci.Specifically,we focused on the dissection of canopy coverage(CC)variation from this rich data set.We also inferred the speed of canopy closure,an additional dimension of CC,from the time-series data,as it may represent an important trait for weed control.Genome-wide association studies(GWASs)identified 35 loci exhibiting dynamic associations with CC across developmental stages.The time-series data enabled the identification of 10 known flowering time and plant height quantitative trait loci(QTLs)detected in previous studies of adult plants and the identification of novel QTLs influencing CC.These novel QTLs were disproportionately likely to act earlier in development,which may explain why they were missed in previous single-time-point studies.Moreover,this time-series data set contributed to the high accuracy of the GWASs,which we evaluated by permutation tests,as evidenced by the repeated identification of loci across multiple time points.Two novel loci showed evidence of adaptive selection during domestication,with different genotypes/haplotypes favored in different geographic regions.In summary,the time-series data,with soybean CC as an example,improved the accuracy and statistical power to dissect the genetic basis of traits and offered a promising opportunity for crop breeding with quantitative growth curves.
文摘The continuous development of hydrogen-electrolyser and fuel-cell technologies not only reduces their investment and operating costs but also improves their technical performance to meet fast-acting requirements of electrical grid balancing services such as frequency-response services.In order to project the feasibility of co-locating a hydrogen-storage system with a wind farm for the dynamic regulation frequency-response provision in Great Britain,this paper develops a modelling framework to coordinate the wind export and frequency responses to the main grid and manage the interaction of the electrolyser,compressor,storage tank and fuel cell within the hydrogen-storage system by respecting the market mechanisms and the balance and conversion of power and hydrogen flows.Then the revenue of frequency-response service provision and a variety of costs induced by the hydrogen-storage system are translated into the net profit of the co-location system,which is maximized by optimizing the capacities of hydrogen-storage-system components,hydrogen-storage levels that guide the hydrogen restoration via operational baselines and the power interchange between a wind-farm and hydrogen-storage system,as well as the capacities tendered for low-and high-frequency dynamic regulation services.The developed modelling framework is tested based on a particular 432-MW offshore wind farm in Great Britain combined with the techno-economics of electrolysers and fuel cells projected for 2030 and 2050 scenarios.The optimized system configuration and operation are compared between different operating scenarios and discussed alongside the prospect of applying hydrogen-storage systems for frequency-response provision.
基金supported by the Strategic Priority Research Programs of the Chinese Academy of Sciences(XDB29020000)the National Natural Science Foundation of China(81722023,81922031)+2 种基金the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences(ZDBS-LY-SM025)the Beijing Natural Science Foundation(7212067)the Youth Innovation Promotion Association of CAS to S.W.
文摘The mucosal immune system is considered a local immune system,a term that implies regional restriction.Mucosal tissues are continually exposed to a wide range of antigens.The regulation of mucosal immune cells is tightly associated with the progression of mucosal diseases.Innate lymphoid cells(ILCs)are abundant in mucosal barriers and serve as first-line defenses against pathogens.The subtype changes and translocation of ILCs are accompanied by the pathologic processes of mucosal diseases.Here,we review the plasticity and circulation of ILCs in the mucosal immune system under physiological and pathological conditions.We also discuss the signaling pathways involved in dynamic ILC changes and the related targets in mucosal diseases.
基金This work was fnancially supported by the National Key R&D Program of China(2020YFA0908500)the Key Program of the National Natural Science Foundation of China(22038005)+1 种基金the Science Fund for Creative Research Groups of the National Science Foundation of China(32021005)the national frst-class discipline program of Light Industry Technology and Engineering(LITE2018-08).
文摘Succinate is an important building block for chemical synthesis.However,during the fermentation process,excessive osmotic stress and byproduct accumulation substantively impair the performance of the microbial cell factory.To this end,two strategies were proposed.First,an osmo-tolerant mutant,Escherichia coli FMME-N-2,was screened by combined mutagenesis(ARTP and^(60)Co-γirradiation)to produce 51.8 g L^(−1)succinate with a productivity of 0.81 g L^(−1)h^(−1).Second,an oxygen-dependent bifunctional switch(OBS)was developed with promoter PfnrF8-based activation and tobacco etch virus protease-based inhibition functions.With ribosomal binding site(RBS)and degron optimization of OBS,the optimal strain E.coli FMME-N-30 achieved a succinate titer and productivity of 119 g L^(−1)and 1.65 g L^(−1) h^(−1),respectively,in a 30-L fermentor,while only 7.1 g L^(−1)acetate and no formate or lactate were detected.Compared to the wild-type strain E.coli FMME-N,the succinate titer was increased by 3.3-fold.These results highlight the applicability of OBS for the large-scale production of value-added chemicals.
基金supported by the National Natural Science Foundation of China(No.21778018)Research Program of State Key Laboratory of Bioreactor Engineering and the grant from the National Key Research and Development Program of China(2021YFC2100300)the Chinese Plastic Surgery Foundation(No.2020M671021).
文摘Itaconic acid(ITA),an effective alternative fossil fuel,derives from the bypass pathway of the tricarboxylic acid(TCA)cycle.Therefore,the imbalance of metabolic flux between TCA cycle and ITA biosynthetic pathway seriously limits the production of ITA.The optimization of flux distribution between biomass and production has the potential to the productivity of ITA.Based on the previously constructed strain Escherichia coli MG1655Δ1-SAS-3(ITA titer:1.87 g/L),a CRISPRi-mediated self-inducible system(CiMS),which contained a responsive module based on the ITA biosensor YpItcR/Pccl and a regulative CRISPRi-mediated interferential module,was developed to regulate the flux of the TCA cycle and to enhance the capacity of the strain to produce ITA.First,a higher ITA-yielding strain,Δ4-Prmd-SAS-3(ITA titer:3.20 g/L),derived fromΔ1-SAS-3,was constructed by replacing the promoter PJ23100,for the expression of ITA synthesis genes,with Prmd and knocking out the three bypass genes poxB,pflB,and ldhA.Subsequently,the CiMS was used to inhibit the expression of key genes icd,pykA,and sucCD to dynamically balance the metabolic flux between TCA cycle and ITA biosynthetic pathway during the ITA production stage.The constructed strainΔ4-Prmd-SAS-3 under the dynamic regulation of the CiMS,showed a 23%increase in the ITA titer,which reached 3.93 g/L.This study indicated that CiMS was a practical strategy to dynamically and precisely regulated the metabolic flux in microbial cell factories.
基金This work was supported by the NSF of China(51672153,51422204,21975141)the National Key Basic Research and Development Program(No.2016YFA0200103)the National Program for Support of Top-notch Young Professionals.
文摘Smart textiles are attracting great interest.Particularly,air-conditioning textiles are highly desired for their merits in energy conservation and personal temperature/humidity management.Currently,air-conditioning textiles can be fabricated by two strategies.One uses infrared-radiation-adaptive materials,and the other uses moisture-responsive actuators that can regulate temperature and humidity simultaneously.Here,the fabrication of a silk-yarn switch comprising electrospun highly aligned nanofibers is reported and its application in air-conditioning textiles is demonstrated.Silk yarn rotates in contact with liquid,and can be recovered by drying.The different responses and wetting behaviors of the switch to H_(2)O and C_(2)H_(6)O is investigated.It is argued that alignment and surface hydrophilicity of nanofibers play important roles in this term.To elaborate,actuating trait is mainly controlled by reduction of the surface free energy of aligned silk nanofibers,during the wetting process.As proof of concept,the application of the sweat-driven silk-yarn switch in regulating the temperature/humidity of the human body is demonstrated in this work.Considering the large production,versatile processibility,and good biocompatibility,silk actuator may have practical applications in designing smart switches(or valves)for intelligent textiles,artificial muscles,and other application scenarios.
基金supported by the Natural Science Foundation of Shanghai(19ZR1472700)the Fok Ying-Tong Education Foundation,China(Grant No.161017)+2 种基金the National Natural Science Foundation of China(Grant No.21776083)the Fundamental Research Funds for the Central Universities(Grant No.22221818014)supported by Open Funding Project of the CAS Key Laboratory of Synthetic Biology.
文摘Syngas,which contains large amount of CO2 as well as H2 and CO,can be convert to acetic acid chemically or biologically.Nowadays,acetic acid become a cost-effective nonfood-based carbon source for value-added biochemical production.In this study,acetic acid and CO2 were used as substrates for the biosynthesis of 3-hydroxypropionic acid(3-HP)in metabolically engineered Escherichia coli carrying heterogeneous acetyl-CoA carboxylase(Acc)from Corynebacterium glutamicum and codon-optimized malonyl-CoA reductase(MCR)from Chloroflexus aurantiacus.Strategies of metabolic engineering included promoting glyoxylate shunt pathway,inhibiting fatty acid synthesis,dynamic regulating of TCA cycle,and enhancing the assimilation of acetic acid.The engineered strain LNY07(M*DA)accumulated 15.8 g/L of 3-HP with the yield of 0.71 g/g in 48 h by whole-cell biocatalysis.Then,syngas-derived acetic acid was used as substrate instead of pure acetic acid.The concentration of 3-HP reached 11.2 g/L with the yield of 0.55 g/g in LNY07(M*DA).The results could potentially contribute to the future development of an industrial bioprocess of 3-HP production from syngas-derived acetic acid.
基金This work was supported by the National Key Research and Development Program of China(2017YFC1600403)the National Science Fund for Excellent Young Scholars(21822806)+2 种基金the National Natural Science Foundation of China(31670095,31770097)the Fundamental Research Funds for the Central Universities(JUSRP51701A)the National First-class Discipline Program of Light Industry Technology and Engineering(LITE2018-08).
文摘There are numerous microorganisms in nature capable of synthesizing diverse useful compounds;however,these natural microorganisms are generally inefficient in the production of target products on an industrial scale,relative to either chemical synthesis or extraction methods.To achieve industrial production of useful compounds,these natural microorganisms must undergo a certain degree of mutation or effective fine-tuning strategies.This review describes how to achieve an ideal metabolic fine-tuned process,including static control strategies and dynamic control strategies.The static control strategies mainly focus on various matabolic engineering strategies,including protein engineering,upregulation/downregulation,and combinatrorial control of these metabolic engineering strategies,to enhance the flexibility of their application in fine-tuned metabolic metworks.Then,we focus on the dynamic control strategies for fine-tuned metabolic metworks.The design principles derived would guide us to construct microbial cell factories for various useful compounds.