Flowering time is a vital aspect of the plant life cycle which signifies the transition from the growth stage to the reproductive stage.To ensure the reproductive success and survival of a species,this narrow window m...Flowering time is a vital aspect of the plant life cycle which signifies the transition from the growth stage to the reproductive stage.To ensure the reproductive success and survival of a species,this narrow window must coincide with various environmental factors including pollinator presence,adequate temperature,and availability of nutrients and water.展开更多
Under solvothermal conditions,1,4‑naphthalenedicarboxylic acid(H_(2)ndc)and 9,9′‑dihexyl‑2,7‑di(pyridin‑4‑yl)fluorene(hfdp)reacted with Co^(2+)ions and Cd^(2+)ions to form two coordination polymers,[Co(hfdp)(ndc)(H2O...Under solvothermal conditions,1,4‑naphthalenedicarboxylic acid(H_(2)ndc)and 9,9′‑dihexyl‑2,7‑di(pyridin‑4‑yl)fluorene(hfdp)reacted with Co^(2+)ions and Cd^(2+)ions to form two coordination polymers,[Co(hfdp)(ndc)(H2O)]·DMA}n(1)and{[Cd(hfdp)(ndc)(H_(2)O)]·DMA}_(n)(2),respectively(DMA=N,N‑dimethylacetamide).Single‑crystal X‑ray diffraction analyses showed that both complexes 1 and 2 contain similar structures.Topological analysis indicates that complexes 1 and 2 have a{44·62}planar structure.In addition,both complexes reveal good thermal stability and fluorescence sensing performance.They exhibited good sensitivity and selectivity towards 2,4,6‑trinitrophenol(TNP)by fluorescent quenching.The limits of detection of 1 and 2 for TNP were 0.107 and 0.327μmol·L^(-1),respectively.CCDC:2475515,1;2475516,2.展开更多
The ionothermal reaction between CuCl_(2),1,4-bis(1,2,4-triazol-1-ylmethyl)benzene(BBTZ),and(NH_(4))_(6)Mo_(7)O_(24) in 1-ethyl-3-methylimidazolium bromide((Emim)Br)led to a new octamolybdate-based coordination polyme...The ionothermal reaction between CuCl_(2),1,4-bis(1,2,4-triazol-1-ylmethyl)benzene(BBTZ),and(NH_(4))_(6)Mo_(7)O_(24) in 1-ethyl-3-methylimidazolium bromide((Emim)Br)led to a new octamolybdate-based coordination polymer(Emim)2[Cu(BBTZ)_(2)(β-Mo_(8)O_(26))](Mo_(8)-CP).Mo_(8)-CP was characterized by elemental analysis,thermogravime-try,IR,powder X-ray diffraction,and single-crystal X-ray diffraction.In Mo_(8)-CP,structural analysis reveals that Cu coordinates with BBTZ ligands to form an interlocked 1D chain.These chains are further bridged by(β-Mo_(8)O_(26))^(4-)to construct a 3D coordination polymer.Notably,(Emim)^(+)acts as a structure-directing agent,occupying the channels of the 3D coordination polymer.Based on this unique structure,the ion exchange properties of Mo_(8)-CP toward rare-earth ions were investigated.It has been found that the luminescent color of the material can be successfully regulat-ed by introducing Eu^(3+)or Tb^(3+)through ion exchange.CCDC:2475110,Mo_(8)-CP.展开更多
Four distinct coordination polymers(CPs)were successfully synthesized by altering solvent types and adjusting ligand concentrations,and their crystal structures were investigated.[Co(L)(FDCA)(H_(2)O)_(2)]·0.5H_(2...Four distinct coordination polymers(CPs)were successfully synthesized by altering solvent types and adjusting ligand concentrations,and their crystal structures were investigated.[Co(L)(FDCA)(H_(2)O)_(2)]·0.5H_(2)O(1)was synthesized as a 2D structure using Coas the metal source,methanol‑water(4∶6,V/V)as the solvent,and specific concentrations of 2,5‑furandicarboxylic acid(H_(2)FDCA)and 1,3,5‑triimidazole benzene(L).Adjusting to pure water and lowering the concentration of L yielded the 1D chain structure of[Co(HL)2(H_(2)O)_(2)](FDCA)_(2)·6H_(2)O(2).Using Cu(Ⅱ)as the metal source,methanol/water(9∶1,V/V)as the solvent,and specific concentrations of L and H2FDCA,the 1D chain structure of[Cu(L)(FDCA)(H_(2)O)]·2H_(2)O(3)was synthesized.Upon increasing the concentrations of L and H2FDCA,and switching the solvent to pure water,the 1D chain structure of[Cu(HL)_(2)(H_(2)O)_(2)](FDCA)_(2)·6H_(2)O(4)was obtained.This shows that changing the solvent and ligand concentrations can affect the structural changes of CPs.In addition,the solid‑state photoluminescence of CPs 1‑4 at room temperature was studied,and their morphological changes were observed via scanning electron microscopy.Density functional theory calculations revealed that the negative charge concentrates on the O and N atoms of the ligand,facilitating ligand‑metal ion coordination.CCDC:2403934,1;2403935,2;2403936,3;2403938,4.展开更多
In wind power transmission via modular multilevel converter based high voltage direct current(MMCHVDC)systems,under traditional control strategies,MMC-HVDCcannot provide inertia support to the receiving-end grid(REG)d...In wind power transmission via modular multilevel converter based high voltage direct current(MMCHVDC)systems,under traditional control strategies,MMC-HVDCcannot provide inertia support to the receiving-end grid(REG)during disturbances.Moreover,due to the frequency decoupling between the two ends of the MMCHVDC,the sending-end wind farm(SEWF)cannot obtain the frequency variation information of the REG to provide inertia response.Therefore,this paper proposes a novel coordinated source-network-storage inertia control strategy based on wind power transmission via MMC-HVDC system.First,the grid-side MMC station(GS-MMC)maps the frequency variations of the REG to direct current(DC)voltage variations through the frequency mapping control,and uses submodule capacitor energy to provide inertial power.Then,the wind farm-side MMC station(WF-MMC)restores the DC voltage variations to frequency variations through the frequency restoration control and power loss compensation,providing real-time frequency information for the wind farm.Finally,based on real-time frequency information,thewind farmutilizes the rotor kinetic energy and energy storage to provide fast and lasting power support through the wind-storage coordinated inertia control strategy.Meanwhile,when the wind turbines withdraw from the inertia response phase,the energy storage can increase the power output to compensate for the power deficit,preventing secondary frequency drops.Furthermore,this paper uses small-signal analysis to determine the appropriate values for the key parameters of the proposed control strategy.A simulation model of the wind power transmission via MMCHVDC system is built in MATLAB/Simulink environment to validate and evaluate the proposed method.The results show that the proposed coordinated control strategy can effectively improve the system inertia level and avoid the secondary frequency drop under the load sudden increase condition.展开更多
To enhance the anesthetic efficacy of propofol while mitigating its systemic toxicity and irreversible developmental neurotoxicity, we developed a strategy leveraging the neuroprotective effects of baicalin in combina...To enhance the anesthetic efficacy of propofol while mitigating its systemic toxicity and irreversible developmental neurotoxicity, we developed a strategy leveraging the neuroprotective effects of baicalin in combination with propofol anesthesia via baicalinbased nanocomposites. High propofol-loaded porous Baicalin-Fe(Ⅲ) infinite coordination polymer@propofol nanocomposites were synthesized, wherein baicalin coordinates with Fe3+ ions to form porous nanoparticles that encapsulate propofol within a core-shell structure. These nanocomposites exhibited an average diameter of 92.3 ± 10.2 nm and a pore volume of 0.322 cm^(3)/g, achieving ultra-high propofol loading(~62%) with no detectable leakage over 100 d, attributed to their large surface area and strong molecular interactions.When combined with focused ultrasound(FUS) and microbubbles, the effective dose(ED_(50))of propofol decreased from 10 to 4.3 mg/kg, doubling the duration of anesthesia and extending the therapeutic window by 200%. Importantly, the therapeutic index improved1.66-fold while vital physiological parameters remained stable. Histological analyses revealed an 80% reduction in neuronal injury compared to free propofol, and behavioral tests demonstrated significant enhancements in motor and cognitive performance, alongside recovery from propofol-induced irreversible developmental neurotoxicity, indicating effective neuroprotection. Collectively, this baicalin-propofol nanocomposite, coupled with FUS-mediated delivery, represents a promising approach for safe and long-term anesthesia in clinical applications.展开更多
Organic room-temperature phosphorescence(RTP)materials are promising for bioimaging applications due to their tunable structures,excellent biocompatibility,and long-lived luminescence.However,the development of highly...Organic room-temperature phosphorescence(RTP)materials are promising for bioimaging applications due to their tunable structures,excellent biocompatibility,and long-lived luminescence.However,the development of highly efficient organic RTP materials for aqueous systems remains challenging,as the organic phosphorescence is prone to being quenched by the dissolved oxygen in water.Herein,heteroaromatic carboxylic acids serve as ligand vips to construct a series of host-vip composites with nontoxic,dense EDTA-M(M=Ca,Mg,and Al)coordination polymer in water.These composites exhibit ultra-long pure RTP of vip molecules with phosphorescence quantum yield up to 53%,and lifetime up to 589.7 ms,due to the synergistic effect of dual-network structure:a coordinatively cross-linked network of EDTA-M,and a non-covalent bonded network formed by ligands and water molecules.The phosphorescence intensity is more than three times that of the composite with a single coordination network.Notably,the dual-network configuration can form a rigid and dense structure and block the intrusion of external H_(2)O and O_(2) molecules to avoid phosphorescence quenching in water.As a result,the RTP of the composites remains unchanged after 1 month in water.Furthermore,the nanoparticles fabricated from composites and anionic surfactants can be successfully applied in in vivo imaging of mice for the stable RTP in water.This work provides a novel strategy for the development of high-performance RTP materials in aqueous systems.展开更多
The neuromuscular junction and its proregenerative niche:The mammalian peripheral nervous system,unlike the central nervous system,has preserved throughout evolution the ability to regenerate and fully restore functio...The neuromuscular junction and its proregenerative niche:The mammalian peripheral nervous system,unlike the central nervous system,has preserved throughout evolution the ability to regenerate and fully restore function.Key factors for effective nerve regeneration include a supportive neuronal environment and a coordinated tissue response(Brosius Lutz and Barres,2014).展开更多
Cooperative pursuit poses challenges across natural,social,and technical systems,particularly when decentralized,slow-speed pursuers attempt to capture a high-speed evader with limited observation.Most existing contri...Cooperative pursuit poses challenges across natural,social,and technical systems,particularly when decentralized,slow-speed pursuers attempt to capture a high-speed evader with limited observation.Most existing contributions place the focus on the greedy pursuit of the evader,overlooking potential collaborations among pursuers.To tackle this issue,a decisionmaking framework of multi-agent coordinated reciprocity formation pursuit(MACRFP)via deep reinforcement learning is introduced.This framework integrates the actor-critic algorithm with the coordinated reciprocity mechanism to enhance the capability of capturing a faster evader.Initially,a local perception model is created by utilizing a cellular network to simulate limitations caused by obstacles.Next,the formation coalition of pursuit is guided by the Cartesian Oval,enabling dispersed pursuers to create a siege against the faster evader.Furthermore,a coordinated reciprocity model based on the coordination graph and the attention-based graph neural networks is developed,addressing the global coordination problem by estimating a reciprocity coefficient to adjust agents'rewards.Numerical simulations demonstrate the emergence of cooperative behaviors in cooperative besiegement,target tracking,and intelligent interception during the pursuit,indicating that the proposed algorithm enhances the feasibility and effectiveness of capturing a fast-escaping target by integrating coordinated reciprocity and coalition formation.展开更多
The Antarctic geodetic datum constitutes a specialized implementation of the modern geodetic reference system within the extreme polar environment.A high-precision,unified,and dynamic Antarctic geodetic datum serves a...The Antarctic geodetic datum constitutes a specialized implementation of the modern geodetic reference system within the extreme polar environment.A high-precision,unified,and dynamic Antarctic geodetic datum serves as critical infrastructure for polar scientific research and engineering safety.This study reviews the composition,current status,and implementation pathways of the Antarctic geodetic datum through four dimensions:coordinate datum,height datum,gravity datum and sounding datum.Preliminary analysis reveals that the development of the Antarctic geodetic datum framework is severely lagging,thereby failing to meet the demands of both scientific expeditions and polar research.To address these challenges,this study proposes an implementation pathway leveraging the 5th International Polar Year(IPY-5)to pioneer regional high-precision geodetic datum in the China’s key research sector covering the area between Amery Ice Shelf and Princess Elizabeth Land,specially highlighting the Prydz Bay–Amery Ice Shelf–Lambert Glacier–Dome A(PANDA)transect,by deploying multi-technique stations andμGal-level superconducting gravimeter networks;and then to integrate multinational observation resources to ultimately establish a high-precision,unified,and dynamic geodetic datum framework.This framework will deliver a spatiotemporal infrastructure for Antarctica to advance the strategic goals of“understanding,protecting,and utilizing Antarctica”.展开更多
Objective:To explore the interventional room nursing and its application effects in patients with ischemic stroke treated with tirofiban combined with direct thrombectomy.Methods:A total of 61 patients with ischemic s...Objective:To explore the interventional room nursing and its application effects in patients with ischemic stroke treated with tirofiban combined with direct thrombectomy.Methods:A total of 61 patients with ischemic stroke admitted to our hospital from June 2024 to June 2025 were selected and divided into two groups using the red and blue ball method:the control group(n=30,receiving routine interventional room nursing)and the observation group(n=31,receiving additional tirofiban medication-specific nursing+individualized interventional nursing on the basis of routine nursing).The cerebral hemodynamic indicators,adverse reactions,effectiveness of complication nursing,and nursing satisfaction were compared between the two groups.Results:After 7 days of treatment,the observation group had lower cerebrovascular peripheral resistance and higher mean blood flow velocity and mean blood flow volume compared to the control group(all p<0.05).The observation group had a higher effectiveness rate of complication nursing than the control group,with a statistically significant difference(p<0.05).The nursing satisfaction in the observation group(96.77%)was higher than that in the control group(80.00%),with a statistically significant difference(χ^(2)=4.223,p=0.040<0.05).Conclusion:Tirofiban combined with direct thrombectomy can significantly improve cerebral hemodynamics,enhance the effectiveness of complication nursing,and increase patient satisfaction in patients with ischemic stroke.展开更多
Stroke patients experience varying degrees of upper limb functional impairment.Although bilateral arm training can help stroke patients recover movement after stroke,little is known about the way in which the brain an...Stroke patients experience varying degrees of upper limb functional impairment.Although bilateral arm training can help stroke patients recover movement after stroke,little is known about the way in which the brain and muscles work together during this type of training.To address this,we conducted a cross-sectional study at The Seventh Affiliated Hospital,Sun Yat-sen University in China,where we observed the connection between brain and muscle activity during bilateral upper limb training in 21 stroke patients and 17 healthy controls.We used functional near-infrared spectroscopy and surface electromyography to measure changes in cerebral cortex oxygenation and upper limb muscle contraction signals,respectively.The results showed that,compared with the healthy control group,stroke patients had reduced functional connectivity and more irregular muscle activity in the affected flexor muscle during bilateral upper limb training.Moreover,we found a significant correlation between the surface electromyographic signal characteristics of upper limb muscles and cerebral oxygenation indicators of multiple brain regions in stroke patients.These findings indicate that bilateral upper limb training is an effective rehabilitation method that improves upper limb motor function in stroke patients by promoting brain functional connectivity and improving muscle activity patterns.展开更多
Single-atom catalysts(SACs)have garnered significant attention in lithium-sulfur(Li-S)batteries for their potential to mitigate the severe polysulfide shuttle effect and sluggish redox kinetics.However,the development...Single-atom catalysts(SACs)have garnered significant attention in lithium-sulfur(Li-S)batteries for their potential to mitigate the severe polysulfide shuttle effect and sluggish redox kinetics.However,the development of highly efficient SACs and a comprehensive understanding of their structure-activity relationships remain enormously challenging.Herein,a novel kind of Fe-based SAC featuring an asymmetric FeN_(5)-TeN_(4) coordination structure was precisely designed by introducing Te atom adjacent to the Fe active center to enhance the catalytic activity.Theoretical calculations reveal that the neighboring Te atom modulates the local coordination environment of the central Fe site,elevating the d-band center closer to the Fermi level and strengthening the d-p orbital hybridization between the catalyst and sulfur species,thereby immobilizing polysulfides and improving the bidirectional catalysis of Li-S redox.Consequently,the Fe-Te atom pair catalyst endows Li-S batteries with exceptional rate performance,achieving a high specific capacity of 735 mAh g^(−1) at 5 C,and remarkable cycling stability with a low decay rate of 0.038%per cycle over 1000 cycles at 1 C.This work provides fundamental insights into the electronic structure modulation of SACs and establishes a clear correlation between precisely engineered atomic configurations and their enhanced catalytic performance in Li-S electrochemistry.展开更多
Grid-Forming(GFM)converters are prone to fault-induced overcurrent and power angle instability during grid fault-induced voltage sags.To address this,this paper develops a multi-loop coordinated fault ridethrough(FRT)...Grid-Forming(GFM)converters are prone to fault-induced overcurrent and power angle instability during grid fault-induced voltage sags.To address this,this paper develops a multi-loop coordinated fault ridethrough(FRT)control strategy based on a power outer loop and voltage-current inner loops,aiming to enhance the stability and current-limiting capability of GFM converters during grid fault conditions.During voltage sags,the GFM converter’s voltage source behavior is maintained by dynamically adjusting the reactive power reference to provide voltage support,thereby effectively suppressing the steady-state component of the fault current.To address the active power imbalance induced by voltage sags,a dynamic active power reference correction method based on apparent power is designed to mitigate power angle oscillations and limit transient current.Moreover,an adaptive virtual impedance loop is implemented to enhance dynamic transient current-limiting performance during the fault initiation phase.This approach improves the responsiveness of the inner loop and ensures safe system operation under various fault severities.Under asymmetric fault conditions,a negative-sequence reactive current compensation strategy is incorporated to further suppress negative-sequence voltage and improve voltage symmetry.The proposed control scheme enables coordinated operation of multiple control objectives,including voltage support,current suppression,and power angle stability,across different fault scenarios.Finally,MATLAB/Simulink simulation results validate the effectiveness of the proposed strategy,showcasing its superior performance in current limiting and power angle stability,thereby significantly enhancing the system’s fault ride-through capability.展开更多
This paper presents an adaptive multi-agent coordination(AMAC)strategy suitable for complex scenarios,which only requires information exchange between neighbouring robots.Unlike traditional multi-agent coordination me...This paper presents an adaptive multi-agent coordination(AMAC)strategy suitable for complex scenarios,which only requires information exchange between neighbouring robots.Unlike traditional multi-agent coordination methods that are solved by neural dynamics,the proposed strategy displays greater flexibility,adaptability and scalability.Furthermore,the proposed AMAC strategy is reconstructed as a time-varying complex-valued matrix equation.By introducing a dynamic error function,a fixed-time convergent zeroing neural network(FTCZNN)model is designed for the online solution of the AMAC strategy,with its convergence time upper bound derived theoretically.Finally,the effectiveness and applicability of the coordination control method are demonstrated by numerical simulations and physical experiments.Numerical results indicate that this method can reduce the formation error to the order of 10^(-6)within 1.8 s.展开更多
Understanding the impacts of human activities on the plateau’s living environment is essential for advancing modernization pathways that promote harmony between humanity and nature.However,studies on the dynamic inte...Understanding the impacts of human activities on the plateau’s living environment is essential for advancing modernization pathways that promote harmony between humanity and nature.However,studies on the dynamic interactions between human activities and the living environment on the Qinghai-Xizang Plateau(QXP)remain limited,with a paucity of quantitative relationship analyses.This study established an assessment framework to evaluate human influences on the living environment in QXP,using data on typical human activities,ecological conditions,and human settlements.Within this framework,the spatial analysis methods and the coupling coordination model were used to examine the spatio-temporal characteristics and relationship of human activities and living environment on the QXP from 2000 to 2020.The geographical detector model was then applied to identify the key factors influencing the plateau’s human living environment.Subsequently,the four-quadrant analysis model was adopted to assess human influences on the living environment.The results indicate that the human activity intensity(HAI)on the QXP remained relatively low yet increased by 15.41%from 2000 to 2020.Spatially,the human living environment quality(LEQ)improved from northwest to southeast,with 61.14%of the areas remaining stable and 18.47%experiencing slight improvement.The analysis of coupling coordination revealed a continuous improvement between the HAI and LEQ,with the areas of high and relatively high coordinated types increasing by more than 9%.Precipitation and urban-rural construction were identified as the primary factors influencing changes in the LEQ.The interaction between the HAI and LEQ was strengthening,with 40.44%classified as coordinated development type and 38.35%as development-environment conflict type.These findings provide valuable insights for enhancing the resilience of human settlements and promoting green development across the plateau.展开更多
Tin-lead(Sn-Pb)halide perovskite single crystals combine narrow bandgaps,long carrier diffusion lengths,and low trap densities,positioning them as ideal candidates for near-infrared(NIR)optoelectronics.However,convent...Tin-lead(Sn-Pb)halide perovskite single crystals combine narrow bandgaps,long carrier diffusion lengths,and low trap densities,positioning them as ideal candidates for near-infrared(NIR)optoelectronics.However,conventional growth strategies rely on bulk crystallization at elevated temperatures,leading to uncontrolled nucleation,Sn^(2+)oxidation,and poor compatibility with planar integration.Here,we develop a coordination-engineered crystallization strategy that enables direct,lowtemperature growth of micrometer-thick Sn-Pb single-crystal thin films on device-compatible substrates.By modulating metal-solvent coordination strength using a low-donor number cosolvent system,we delineate a narrow processing window that stabilizes precursor speciation,lowers the nucleation barrier,and guides directional crystal growth under mild thermal conditions(<40℃).The resulting crystal films exhibit smooth morphology,high crystallinity,compositional uniformity,and ultralow trap densities(~3.98×10^(12)cm^(-3)).When integrated into NIR photodetectors,these films deliver high responsivity(0.51 A W^(-1)at 900 nm),specific detectivity up to 3.6×10^(12)Jones,fast response(~188μs),and>25,000 cycles of ambient operational stability.This approach establishes a scalable platform for redox-stable,low-temperature growth of Sn-Pb perovskite crystal films and expands the processing-structure-function landscape for next-generation infrared optoelectronics.展开更多
Prussian blue analogs(PBAs)are considered one of the excellent cathode materials for sodium-ion batteries due to their low cost and high theoretical specific capacity,especially sodium-rich iron-based PBAs(FeHCF)can p...Prussian blue analogs(PBAs)are considered one of the excellent cathode materials for sodium-ion batteries due to their low cost and high theoretical specific capacity,especially sodium-rich iron-based PBAs(FeHCF)can provide higher energy density.FeHCF has a poor charge/discharge platform stability at high voltages(FeC_(6)moiety),which is mainly affected by its coordination environment.In this research,Cu^(+)(six-coordinated),which is close to the ionic radius of Fe^(2+),was used for substitution,the FeC_(6)vacancies of FeHCF were reduced,and the coordination environment was optimized.The low Cu^(+)-substituted FeHCF(Cu^(+)0.625)has an optimal electrochemical performance at 8.5 mA/g with a reversible specific capacity of 142 mA h/g and FeC_(6)moiety contribution of more than 68 mA h/g,which is superior to that of unmodified and other Cu^(2+)-substituted FeHCFs.In situ tests demonstrate the reversible structural stability of the Cu^(+)0.625,supporting the stability of their high-voltage platform capacity.This Cu^(+)substitution strategy further enriches the approach to optimize the coordination environment of sodium-rich FeHCF.展开更多
Exploiting effective approaches to achieve superior ductility has consistently been a topic of widespread interest in refractory multi-principal-element alloys(RMPEAs).Herein,we developed a one-step forming method,ele...Exploiting effective approaches to achieve superior ductility has consistently been a topic of widespread interest in refractory multi-principal-element alloys(RMPEAs).Herein,we developed a one-step forming method,electron-beam directional-solidification(EB-DS),to fabricate an equiatomic Hf-Nb-Ta-Zr RMPEA,and compared its microstructures as well as mechanical properties with those of the as-cast alloy fabricated by levitation induction melting.EB-DS method can transform the equiaxed grain microstructures in the as-cast alloy to columnar grain microstructures as well as eliminate the slight segregation.The room-temperature tensile test demonstrates that the ductility is substantially improved from 3.9%for the as-cast alloy to 23%for EB-DS alloy,accompanied by the slight enhancement in yield strength from 946 to 991 MPa.The microstructural investigations indicate that EB-DS alloys with columnar grains present a significantly optimized coordinated plastic deformation between the grain boundary region and the grain interior region,leading to the suppression of cracking along grain boundaries.展开更多
基金This work was supported by the National Natural Science Foundation of China(32000242 to Y.S.,32000241 to H.Z.,and 31871278 and U19A2021 to Y.D.)the Strategic Priority Research Program"Molecular Mechanisms of Plant Growth and Development"of CAS(XDB27030203).
文摘Flowering time is a vital aspect of the plant life cycle which signifies the transition from the growth stage to the reproductive stage.To ensure the reproductive success and survival of a species,this narrow window must coincide with various environmental factors including pollinator presence,adequate temperature,and availability of nutrients and water.
文摘Under solvothermal conditions,1,4‑naphthalenedicarboxylic acid(H_(2)ndc)and 9,9′‑dihexyl‑2,7‑di(pyridin‑4‑yl)fluorene(hfdp)reacted with Co^(2+)ions and Cd^(2+)ions to form two coordination polymers,[Co(hfdp)(ndc)(H2O)]·DMA}n(1)and{[Cd(hfdp)(ndc)(H_(2)O)]·DMA}_(n)(2),respectively(DMA=N,N‑dimethylacetamide).Single‑crystal X‑ray diffraction analyses showed that both complexes 1 and 2 contain similar structures.Topological analysis indicates that complexes 1 and 2 have a{44·62}planar structure.In addition,both complexes reveal good thermal stability and fluorescence sensing performance.They exhibited good sensitivity and selectivity towards 2,4,6‑trinitrophenol(TNP)by fluorescent quenching.The limits of detection of 1 and 2 for TNP were 0.107 and 0.327μmol·L^(-1),respectively.CCDC:2475515,1;2475516,2.
文摘The ionothermal reaction between CuCl_(2),1,4-bis(1,2,4-triazol-1-ylmethyl)benzene(BBTZ),and(NH_(4))_(6)Mo_(7)O_(24) in 1-ethyl-3-methylimidazolium bromide((Emim)Br)led to a new octamolybdate-based coordination polymer(Emim)2[Cu(BBTZ)_(2)(β-Mo_(8)O_(26))](Mo_(8)-CP).Mo_(8)-CP was characterized by elemental analysis,thermogravime-try,IR,powder X-ray diffraction,and single-crystal X-ray diffraction.In Mo_(8)-CP,structural analysis reveals that Cu coordinates with BBTZ ligands to form an interlocked 1D chain.These chains are further bridged by(β-Mo_(8)O_(26))^(4-)to construct a 3D coordination polymer.Notably,(Emim)^(+)acts as a structure-directing agent,occupying the channels of the 3D coordination polymer.Based on this unique structure,the ion exchange properties of Mo_(8)-CP toward rare-earth ions were investigated.It has been found that the luminescent color of the material can be successfully regulat-ed by introducing Eu^(3+)or Tb^(3+)through ion exchange.CCDC:2475110,Mo_(8)-CP.
文摘Four distinct coordination polymers(CPs)were successfully synthesized by altering solvent types and adjusting ligand concentrations,and their crystal structures were investigated.[Co(L)(FDCA)(H_(2)O)_(2)]·0.5H_(2)O(1)was synthesized as a 2D structure using Coas the metal source,methanol‑water(4∶6,V/V)as the solvent,and specific concentrations of 2,5‑furandicarboxylic acid(H_(2)FDCA)and 1,3,5‑triimidazole benzene(L).Adjusting to pure water and lowering the concentration of L yielded the 1D chain structure of[Co(HL)2(H_(2)O)_(2)](FDCA)_(2)·6H_(2)O(2).Using Cu(Ⅱ)as the metal source,methanol/water(9∶1,V/V)as the solvent,and specific concentrations of L and H2FDCA,the 1D chain structure of[Cu(L)(FDCA)(H_(2)O)]·2H_(2)O(3)was synthesized.Upon increasing the concentrations of L and H2FDCA,and switching the solvent to pure water,the 1D chain structure of[Cu(HL)_(2)(H_(2)O)_(2)](FDCA)_(2)·6H_(2)O(4)was obtained.This shows that changing the solvent and ligand concentrations can affect the structural changes of CPs.In addition,the solid‑state photoluminescence of CPs 1‑4 at room temperature was studied,and their morphological changes were observed via scanning electron microscopy.Density functional theory calculations revealed that the negative charge concentrates on the O and N atoms of the ligand,facilitating ligand‑metal ion coordination.CCDC:2403934,1;2403935,2;2403936,3;2403938,4.
基金funded by State Grid Corporation of China Central Branch Technology Project(52140024000C).
文摘In wind power transmission via modular multilevel converter based high voltage direct current(MMCHVDC)systems,under traditional control strategies,MMC-HVDCcannot provide inertia support to the receiving-end grid(REG)during disturbances.Moreover,due to the frequency decoupling between the two ends of the MMCHVDC,the sending-end wind farm(SEWF)cannot obtain the frequency variation information of the REG to provide inertia response.Therefore,this paper proposes a novel coordinated source-network-storage inertia control strategy based on wind power transmission via MMC-HVDC system.First,the grid-side MMC station(GS-MMC)maps the frequency variations of the REG to direct current(DC)voltage variations through the frequency mapping control,and uses submodule capacitor energy to provide inertial power.Then,the wind farm-side MMC station(WF-MMC)restores the DC voltage variations to frequency variations through the frequency restoration control and power loss compensation,providing real-time frequency information for the wind farm.Finally,based on real-time frequency information,thewind farmutilizes the rotor kinetic energy and energy storage to provide fast and lasting power support through the wind-storage coordinated inertia control strategy.Meanwhile,when the wind turbines withdraw from the inertia response phase,the energy storage can increase the power output to compensate for the power deficit,preventing secondary frequency drops.Furthermore,this paper uses small-signal analysis to determine the appropriate values for the key parameters of the proposed control strategy.A simulation model of the wind power transmission via MMCHVDC system is built in MATLAB/Simulink environment to validate and evaluate the proposed method.The results show that the proposed coordinated control strategy can effectively improve the system inertia level and avoid the secondary frequency drop under the load sudden increase condition.
基金funded by the National Natural Science Foundation of China (No. 82271572)The Clinical Research Award of the First Affiliated Hospital of Xi'an Jiaotong University (No. XJTU1AF2021CRF-008) and (No. XTJU1AF-CRF2023-025)。
文摘To enhance the anesthetic efficacy of propofol while mitigating its systemic toxicity and irreversible developmental neurotoxicity, we developed a strategy leveraging the neuroprotective effects of baicalin in combination with propofol anesthesia via baicalinbased nanocomposites. High propofol-loaded porous Baicalin-Fe(Ⅲ) infinite coordination polymer@propofol nanocomposites were synthesized, wherein baicalin coordinates with Fe3+ ions to form porous nanoparticles that encapsulate propofol within a core-shell structure. These nanocomposites exhibited an average diameter of 92.3 ± 10.2 nm and a pore volume of 0.322 cm^(3)/g, achieving ultra-high propofol loading(~62%) with no detectable leakage over 100 d, attributed to their large surface area and strong molecular interactions.When combined with focused ultrasound(FUS) and microbubbles, the effective dose(ED_(50))of propofol decreased from 10 to 4.3 mg/kg, doubling the duration of anesthesia and extending the therapeutic window by 200%. Importantly, the therapeutic index improved1.66-fold while vital physiological parameters remained stable. Histological analyses revealed an 80% reduction in neuronal injury compared to free propofol, and behavioral tests demonstrated significant enhancements in motor and cognitive performance, alongside recovery from propofol-induced irreversible developmental neurotoxicity, indicating effective neuroprotection. Collectively, this baicalin-propofol nanocomposite, coupled with FUS-mediated delivery, represents a promising approach for safe and long-term anesthesia in clinical applications.
基金supported by the Startup Funds for Introduced Talents of Wuyi University(YJ202304)the National Natural Science Foundation of China(22375044).
文摘Organic room-temperature phosphorescence(RTP)materials are promising for bioimaging applications due to their tunable structures,excellent biocompatibility,and long-lived luminescence.However,the development of highly efficient organic RTP materials for aqueous systems remains challenging,as the organic phosphorescence is prone to being quenched by the dissolved oxygen in water.Herein,heteroaromatic carboxylic acids serve as ligand vips to construct a series of host-vip composites with nontoxic,dense EDTA-M(M=Ca,Mg,and Al)coordination polymer in water.These composites exhibit ultra-long pure RTP of vip molecules with phosphorescence quantum yield up to 53%,and lifetime up to 589.7 ms,due to the synergistic effect of dual-network structure:a coordinatively cross-linked network of EDTA-M,and a non-covalent bonded network formed by ligands and water molecules.The phosphorescence intensity is more than three times that of the composite with a single coordination network.Notably,the dual-network configuration can form a rigid and dense structure and block the intrusion of external H_(2)O and O_(2) molecules to avoid phosphorescence quenching in water.As a result,the RTP of the composites remains unchanged after 1 month in water.Furthermore,the nanoparticles fabricated from composites and anionic surfactants can be successfully applied in in vivo imaging of mice for the stable RTP in water.This work provides a novel strategy for the development of high-performance RTP materials in aqueous systems.
基金supported by the University of Padua(to MR)by the project“RIPANE”of the Italian Ministry of Defense(to CM)by Cariparo Foundation(to CM)。
文摘The neuromuscular junction and its proregenerative niche:The mammalian peripheral nervous system,unlike the central nervous system,has preserved throughout evolution the ability to regenerate and fully restore function.Key factors for effective nerve regeneration include a supportive neuronal environment and a coordinated tissue response(Brosius Lutz and Barres,2014).
基金supported by the National Natural Science Foundation of China(72371052,71871042)。
文摘Cooperative pursuit poses challenges across natural,social,and technical systems,particularly when decentralized,slow-speed pursuers attempt to capture a high-speed evader with limited observation.Most existing contributions place the focus on the greedy pursuit of the evader,overlooking potential collaborations among pursuers.To tackle this issue,a decisionmaking framework of multi-agent coordinated reciprocity formation pursuit(MACRFP)via deep reinforcement learning is introduced.This framework integrates the actor-critic algorithm with the coordinated reciprocity mechanism to enhance the capability of capturing a faster evader.Initially,a local perception model is created by utilizing a cellular network to simulate limitations caused by obstacles.Next,the formation coalition of pursuit is guided by the Cartesian Oval,enabling dispersed pursuers to create a siege against the faster evader.Furthermore,a coordinated reciprocity model based on the coordination graph and the attention-based graph neural networks is developed,addressing the global coordination problem by estimating a reciprocity coefficient to adjust agents'rewards.Numerical simulations demonstrate the emergence of cooperative behaviors in cooperative besiegement,target tracking,and intelligent interception during the pursuit,indicating that the proposed algorithm enhances the feasibility and effectiveness of capturing a fast-escaping target by integrating coordinated reciprocity and coalition formation.
文摘The Antarctic geodetic datum constitutes a specialized implementation of the modern geodetic reference system within the extreme polar environment.A high-precision,unified,and dynamic Antarctic geodetic datum serves as critical infrastructure for polar scientific research and engineering safety.This study reviews the composition,current status,and implementation pathways of the Antarctic geodetic datum through four dimensions:coordinate datum,height datum,gravity datum and sounding datum.Preliminary analysis reveals that the development of the Antarctic geodetic datum framework is severely lagging,thereby failing to meet the demands of both scientific expeditions and polar research.To address these challenges,this study proposes an implementation pathway leveraging the 5th International Polar Year(IPY-5)to pioneer regional high-precision geodetic datum in the China’s key research sector covering the area between Amery Ice Shelf and Princess Elizabeth Land,specially highlighting the Prydz Bay–Amery Ice Shelf–Lambert Glacier–Dome A(PANDA)transect,by deploying multi-technique stations andμGal-level superconducting gravimeter networks;and then to integrate multinational observation resources to ultimately establish a high-precision,unified,and dynamic geodetic datum framework.This framework will deliver a spatiotemporal infrastructure for Antarctica to advance the strategic goals of“understanding,protecting,and utilizing Antarctica”.
文摘Objective:To explore the interventional room nursing and its application effects in patients with ischemic stroke treated with tirofiban combined with direct thrombectomy.Methods:A total of 61 patients with ischemic stroke admitted to our hospital from June 2024 to June 2025 were selected and divided into two groups using the red and blue ball method:the control group(n=30,receiving routine interventional room nursing)and the observation group(n=31,receiving additional tirofiban medication-specific nursing+individualized interventional nursing on the basis of routine nursing).The cerebral hemodynamic indicators,adverse reactions,effectiveness of complication nursing,and nursing satisfaction were compared between the two groups.Results:After 7 days of treatment,the observation group had lower cerebrovascular peripheral resistance and higher mean blood flow velocity and mean blood flow volume compared to the control group(all p<0.05).The observation group had a higher effectiveness rate of complication nursing than the control group,with a statistically significant difference(p<0.05).The nursing satisfaction in the observation group(96.77%)was higher than that in the control group(80.00%),with a statistically significant difference(χ^(2)=4.223,p=0.040<0.05).Conclusion:Tirofiban combined with direct thrombectomy can significantly improve cerebral hemodynamics,enhance the effectiveness of complication nursing,and increase patient satisfaction in patients with ischemic stroke.
文摘Stroke patients experience varying degrees of upper limb functional impairment.Although bilateral arm training can help stroke patients recover movement after stroke,little is known about the way in which the brain and muscles work together during this type of training.To address this,we conducted a cross-sectional study at The Seventh Affiliated Hospital,Sun Yat-sen University in China,where we observed the connection between brain and muscle activity during bilateral upper limb training in 21 stroke patients and 17 healthy controls.We used functional near-infrared spectroscopy and surface electromyography to measure changes in cerebral cortex oxygenation and upper limb muscle contraction signals,respectively.The results showed that,compared with the healthy control group,stroke patients had reduced functional connectivity and more irregular muscle activity in the affected flexor muscle during bilateral upper limb training.Moreover,we found a significant correlation between the surface electromyographic signal characteristics of upper limb muscles and cerebral oxygenation indicators of multiple brain regions in stroke patients.These findings indicate that bilateral upper limb training is an effective rehabilitation method that improves upper limb motor function in stroke patients by promoting brain functional connectivity and improving muscle activity patterns.
基金supported by the National Natural Science Foundation(52302284,22002086,22204096)Shanghai Sailing Program(23YF1412200)the Fundamental Research Funds for the Central Universities(22120240314).
文摘Single-atom catalysts(SACs)have garnered significant attention in lithium-sulfur(Li-S)batteries for their potential to mitigate the severe polysulfide shuttle effect and sluggish redox kinetics.However,the development of highly efficient SACs and a comprehensive understanding of their structure-activity relationships remain enormously challenging.Herein,a novel kind of Fe-based SAC featuring an asymmetric FeN_(5)-TeN_(4) coordination structure was precisely designed by introducing Te atom adjacent to the Fe active center to enhance the catalytic activity.Theoretical calculations reveal that the neighboring Te atom modulates the local coordination environment of the central Fe site,elevating the d-band center closer to the Fermi level and strengthening the d-p orbital hybridization between the catalyst and sulfur species,thereby immobilizing polysulfides and improving the bidirectional catalysis of Li-S redox.Consequently,the Fe-Te atom pair catalyst endows Li-S batteries with exceptional rate performance,achieving a high specific capacity of 735 mAh g^(−1) at 5 C,and remarkable cycling stability with a low decay rate of 0.038%per cycle over 1000 cycles at 1 C.This work provides fundamental insights into the electronic structure modulation of SACs and establishes a clear correlation between precisely engineered atomic configurations and their enhanced catalytic performance in Li-S electrochemistry.
文摘Grid-Forming(GFM)converters are prone to fault-induced overcurrent and power angle instability during grid fault-induced voltage sags.To address this,this paper develops a multi-loop coordinated fault ridethrough(FRT)control strategy based on a power outer loop and voltage-current inner loops,aiming to enhance the stability and current-limiting capability of GFM converters during grid fault conditions.During voltage sags,the GFM converter’s voltage source behavior is maintained by dynamically adjusting the reactive power reference to provide voltage support,thereby effectively suppressing the steady-state component of the fault current.To address the active power imbalance induced by voltage sags,a dynamic active power reference correction method based on apparent power is designed to mitigate power angle oscillations and limit transient current.Moreover,an adaptive virtual impedance loop is implemented to enhance dynamic transient current-limiting performance during the fault initiation phase.This approach improves the responsiveness of the inner loop and ensures safe system operation under various fault severities.Under asymmetric fault conditions,a negative-sequence reactive current compensation strategy is incorporated to further suppress negative-sequence voltage and improve voltage symmetry.The proposed control scheme enables coordinated operation of multiple control objectives,including voltage support,current suppression,and power angle stability,across different fault scenarios.Finally,MATLAB/Simulink simulation results validate the effectiveness of the proposed strategy,showcasing its superior performance in current limiting and power angle stability,thereby significantly enhancing the system’s fault ride-through capability.
基金supported by the National Natural Science Foundation of China under Grants 61962023,61562029 and 62466019.
文摘This paper presents an adaptive multi-agent coordination(AMAC)strategy suitable for complex scenarios,which only requires information exchange between neighbouring robots.Unlike traditional multi-agent coordination methods that are solved by neural dynamics,the proposed strategy displays greater flexibility,adaptability and scalability.Furthermore,the proposed AMAC strategy is reconstructed as a time-varying complex-valued matrix equation.By introducing a dynamic error function,a fixed-time convergent zeroing neural network(FTCZNN)model is designed for the online solution of the AMAC strategy,with its convergence time upper bound derived theoretically.Finally,the effectiveness and applicability of the coordination control method are demonstrated by numerical simulations and physical experiments.Numerical results indicate that this method can reduce the formation error to the order of 10^(-6)within 1.8 s.
基金The Second Tibetan Plateau Scientific Expedition and Research Program,No.2019QZKK0608。
文摘Understanding the impacts of human activities on the plateau’s living environment is essential for advancing modernization pathways that promote harmony between humanity and nature.However,studies on the dynamic interactions between human activities and the living environment on the Qinghai-Xizang Plateau(QXP)remain limited,with a paucity of quantitative relationship analyses.This study established an assessment framework to evaluate human influences on the living environment in QXP,using data on typical human activities,ecological conditions,and human settlements.Within this framework,the spatial analysis methods and the coupling coordination model were used to examine the spatio-temporal characteristics and relationship of human activities and living environment on the QXP from 2000 to 2020.The geographical detector model was then applied to identify the key factors influencing the plateau’s human living environment.Subsequently,the four-quadrant analysis model was adopted to assess human influences on the living environment.The results indicate that the human activity intensity(HAI)on the QXP remained relatively low yet increased by 15.41%from 2000 to 2020.Spatially,the human living environment quality(LEQ)improved from northwest to southeast,with 61.14%of the areas remaining stable and 18.47%experiencing slight improvement.The analysis of coupling coordination revealed a continuous improvement between the HAI and LEQ,with the areas of high and relatively high coordinated types increasing by more than 9%.Precipitation and urban-rural construction were identified as the primary factors influencing changes in the LEQ.The interaction between the HAI and LEQ was strengthening,with 40.44%classified as coordinated development type and 38.35%as development-environment conflict type.These findings provide valuable insights for enhancing the resilience of human settlements and promoting green development across the plateau.
基金support received from the National Research Foundation of Korea(NRF)through the Ministry of Science,ICT(Information and Communication Technology),under grant numbers RS-2023-00302646 and RS-2025-02316700.
文摘Tin-lead(Sn-Pb)halide perovskite single crystals combine narrow bandgaps,long carrier diffusion lengths,and low trap densities,positioning them as ideal candidates for near-infrared(NIR)optoelectronics.However,conventional growth strategies rely on bulk crystallization at elevated temperatures,leading to uncontrolled nucleation,Sn^(2+)oxidation,and poor compatibility with planar integration.Here,we develop a coordination-engineered crystallization strategy that enables direct,lowtemperature growth of micrometer-thick Sn-Pb single-crystal thin films on device-compatible substrates.By modulating metal-solvent coordination strength using a low-donor number cosolvent system,we delineate a narrow processing window that stabilizes precursor speciation,lowers the nucleation barrier,and guides directional crystal growth under mild thermal conditions(<40℃).The resulting crystal films exhibit smooth morphology,high crystallinity,compositional uniformity,and ultralow trap densities(~3.98×10^(12)cm^(-3)).When integrated into NIR photodetectors,these films deliver high responsivity(0.51 A W^(-1)at 900 nm),specific detectivity up to 3.6×10^(12)Jones,fast response(~188μs),and>25,000 cycles of ambient operational stability.This approach establishes a scalable platform for redox-stable,low-temperature growth of Sn-Pb perovskite crystal films and expands the processing-structure-function landscape for next-generation infrared optoelectronics.
基金supported by the Key Talent Project of Gansu Province(2025RCXM017)the National Natural Science Foundation of China(52261040)+2 种基金the Postgraduate Innovation Star Program of Gansu Province(2025CXZX-476)the Major Science and Technology Project of Gansu Province(22ZD6GA008)the Innovation Driven Assistance Engineering Project of Gansu Association for Science and Technology(GXH20250325-5).
文摘Prussian blue analogs(PBAs)are considered one of the excellent cathode materials for sodium-ion batteries due to their low cost and high theoretical specific capacity,especially sodium-rich iron-based PBAs(FeHCF)can provide higher energy density.FeHCF has a poor charge/discharge platform stability at high voltages(FeC_(6)moiety),which is mainly affected by its coordination environment.In this research,Cu^(+)(six-coordinated),which is close to the ionic radius of Fe^(2+),was used for substitution,the FeC_(6)vacancies of FeHCF were reduced,and the coordination environment was optimized.The low Cu^(+)-substituted FeHCF(Cu^(+)0.625)has an optimal electrochemical performance at 8.5 mA/g with a reversible specific capacity of 142 mA h/g and FeC_(6)moiety contribution of more than 68 mA h/g,which is superior to that of unmodified and other Cu^(2+)-substituted FeHCFs.In situ tests demonstrate the reversible structural stability of the Cu^(+)0.625,supporting the stability of their high-voltage platform capacity.This Cu^(+)substitution strategy further enriches the approach to optimize the coordination environment of sodium-rich FeHCF.
基金supported by the National Key R&D Program of China(Grant No.2023YFB3508700)the National Natural Science Foundation of China(NSFC,Grant Nos.52227801 and 52271162)the Fundamental Research Funds for the Central Universities.
文摘Exploiting effective approaches to achieve superior ductility has consistently been a topic of widespread interest in refractory multi-principal-element alloys(RMPEAs).Herein,we developed a one-step forming method,electron-beam directional-solidification(EB-DS),to fabricate an equiatomic Hf-Nb-Ta-Zr RMPEA,and compared its microstructures as well as mechanical properties with those of the as-cast alloy fabricated by levitation induction melting.EB-DS method can transform the equiaxed grain microstructures in the as-cast alloy to columnar grain microstructures as well as eliminate the slight segregation.The room-temperature tensile test demonstrates that the ductility is substantially improved from 3.9%for the as-cast alloy to 23%for EB-DS alloy,accompanied by the slight enhancement in yield strength from 946 to 991 MPa.The microstructural investigations indicate that EB-DS alloys with columnar grains present a significantly optimized coordinated plastic deformation between the grain boundary region and the grain interior region,leading to the suppression of cracking along grain boundaries.
