An in-depth analysis on the cooperativity of intermolecular interactions including hydrogen bonding andπ-π stacking in 1,3,5-triamino-2,4,6-trinitrobenzene(TATB) crystal was studied. Two quantities, cooperativity ra...An in-depth analysis on the cooperativity of intermolecular interactions including hydrogen bonding andπ-π stacking in 1,3,5-triamino-2,4,6-trinitrobenzene(TATB) crystal was studied. Two quantities, cooperativity rate and energy, were defined to evaluate the nature and strength of cooperativity in a series of clusters diverging from 1D to 3D prototypes. The origin and mechanism of the cooperative effect were settled to demonstrate that the nature of cooperativity is determined by whether the non-covalent interactions compete or promote with each other, which is manifested by the changing trend of electron transfer. There exists obvious cooperative effect in intra-layer and inter-layer structures as they own the equivalent non-covalent interactions, while anti-cooperative effect is also observed if two interactions correlate with each other. On the whole, in the process of crystal formation, the apparent cooperativity is the check and balance of the two effects, which is capable to support a global interaction among all of molecules and contribute to the stabilization of system. Based on the results, one may get a new insight to understand the relationship between non-covalent interactions and low impact sensitivity.展开更多
Molecular dynamics method was employed to study the binding energies of the selected crystal planes of the 1,3,5,7-tetranitro-1,3,5,7-tetrazacyclooctane（HMX）/1,3-dimethyl-2-imidazolidinone（DMI） cocrystal in differ...Molecular dynamics method was employed to study the binding energies of the selected crystal planes of the 1,3,5,7-tetranitro-1,3,5,7-tetrazacyclooctane（HMX）/1,3-dimethyl-2-imidazolidinone（DMI） cocrystal in different molecular molar ratios. The mechanical properties were estimated in different molar ratios. Solvent effects were evaluated and the cooperativity effects were discussed in the HMX···HF···DMI ternary by using the M06-2x/6-311＋G（2df,2p） and MP2（full）/6-311＋G（2df,2p） methods. The results indicate that the substituted patterns（020） and（100） own the highest binding energies. The stabilities of cocrystals in the 1：1 and 2：1 ratios are the greatest, and thus the HMX/DMI cocrystals prefer cocrystallizing in the 1：1 and 2：1 molar ratios, which have good mechanical properties. The sensitivity change of cocrystal originates from not only the formation of intermolecular interaction but also the increment of bond dissociation energy of the N–NO2 bond. The cooperativity effect appears in the linear complex while the anti-cooperativity effect is found in the cyclic system. DMI binding to HMX is not energetically and structurally favored in the presence of HF. This is perhaps the reason that the solvent with large dielectric constant weakens the stability of the HMX/DMI cocrystals. Therefore, the solvents with low dielectric constants should be chosen in the preparation of HMX/DMI cocrystals.展开更多
A bifunctional heterogeneous catalyst containing two mutually incompatible acidic and basic sites, which exhibits cooperative catalytic behavior in the aldol condensation of acetone and various aldehydes, was synthesi...A bifunctional heterogeneous catalyst containing two mutually incompatible acidic and basic sites, which exhibits cooperative catalytic behavior in the aldol condensation of acetone and various aldehydes, was synthesized by postgrafting of 1,5,7- triazabicyclo[4.4.0] dec-5-ene （TBD, a sterically hindered organic base） onto AI-MCM-41 molecular sieve. 2009 Xiao Bing Lu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.展开更多
Thermodynamic data were determined for the reversible binding of O 2 to two compounds of dicobalt(II) di(meso tetra phenyl)porphyrin derivatives with different lengths of diamidoaliphatic bridge (abbreviated to Co ...Thermodynamic data were determined for the reversible binding of O 2 to two compounds of dicobalt(II) di(meso tetra phenyl)porphyrin derivatives with different lengths of diamidoaliphatic bridge (abbreviated to Co 2PP 8 and Co 2PP 4) in N,N dimethylformamide at room temperature. The partial pressure of dioxygen necessary for half oxygenation ( P 1/2 ) and Hill coefficient ( n ) at 298 K were determined as follows: P 1/2 =54.2 kPa, n =2.0 for Co 2PP 8 and P 1/2 =6.8 kPa, n =1.8 for Co 2PP 4,respectively. The rate equations of reversible oxygen binding by Co 2PP 8 were determined and the reaction path was proposed. The results of thermodynamic and kinetic studies indicate that there exists strong cooperative effect during oxygenation of the compounds. The ESR observation reveals that the dioxygen complexes formed in the solutions are of superoxo (Co O - 2) type.展开更多
Here we examine the findings obtained for disaccharide/water mixtures near glass transition that involves cooperative relaxation features on kinetic by viscosity and on thermodynamic behaviour by neutron scattering. T...Here we examine the findings obtained for disaccharide/water mixtures near glass transition that involves cooperative relaxation features on kinetic by viscosity and on thermodynamic behaviour by neutron scattering. Then to address cooperative phenomena that mitigate the Debye-Waller behaviour we invoke Adam-Gibbs’ idea of a cooperative rearranging region. Neutron results suggest that the excess mean square displacement behaves as free volume and is closely connected to an elementary step of the structural relaxation. Then viscosity data evidence a breakdown of the Einstein-Debye relation, decoupling attributed to the intermolecular cooperativity.展开更多
The Arabidopsis phosphoinositide kinases PI4Kβ1 and PIP5K5 have been implicated in the control of directional vesicle trafficking underlying polar tip growth in pollen tubes. PI4Kβ1 and PIP5K5 catalyze key consecuti...The Arabidopsis phosphoinositide kinases PI4Kβ1 and PIP5K5 have been implicated in the control of directional vesicle trafficking underlying polar tip growth in pollen tubes. PI4Kβ1 and PIP5K5 catalyze key consecutive steps of phosphoinositide conversion, and it appears obvious that phosphatidylinositol-4-phosphate formed by PI4Kβ1 might act as a substrate for phosphatidylinositol-4,5-bisphosphate formation by PIP5K5. However, this hypothesis has not been experimentally addressed and distinct localization patterns of PI4Kβ1, PIP5K5, and also PI-synthases （PIS） generating phosphatidylinositol suggest additional complexity. Here, the synergistic functionality of enzymes of phosphoinositide conversion was assessed. In tobacco and Arabidopsis pollen tubes, phosphoinositides influence the apical secretion of pectin, and increased pectin deposition results in characteristic morphological alterations. Catalytically active and dominant negative variants of PI4Kβ1 and PIP5K5 were systematically co-expressed in tobacco pollen tubes and the incidence of morphologies related to enhanced pectin secretion was evaluated. The data support a proposed functional interplay of PI4Kβ1 and PIP5K5 at the trans-Golgi network, mediating directional vesicle trafficking. Co-expression experiments additionally including PIS isoforms, PIS1 or PIS2, indicate that pectin secretion is synergistically mediated by PI4Kβ1 and PIPSK5 acting on Ptdlns formed by PIS2 rather than PIS1. Possible ramifications for the preferential channeling of phosphoinositide intermediates between particular isoforms of PI pathway enzymes are discussed.展开更多
This paper studies cooperative robust parallel operation of multiple actuators over an undirected communication graph.The plant is modeled as an uncertain linear system,and the actuators are linear and identical.Based...This paper studies cooperative robust parallel operation of multiple actuators over an undirected communication graph.The plant is modeled as an uncertain linear system,and the actuators are linear and identical.Based on the internal model principle,a distributed dynamic output feedback control law is proposed to achieve both robust output regulation of the closed-loop system and plant input sharing among the actuators.A practical example of five motors cooperatively driving an uncertain shaft under an external load torque is presented to show the effectiveness of the proposed control law.展开更多
Fatty acid binding and oxidation kinetics for wild type P450_(BM3)(CYP102A1)from Bacillus megaterium have been found to display chain length-dependent homotropic behavior.Laurate and 13-methyl-myristate display Michae...Fatty acid binding and oxidation kinetics for wild type P450_(BM3)(CYP102A1)from Bacillus megaterium have been found to display chain length-dependent homotropic behavior.Laurate and 13-methyl-myristate display Michaelis-Menten behavior while there are slight deviations with myristate at low ionic strengths.Palmitate shows Michaelis-Menten kinetics and hyperbolic binding behavior in 100 mmol/L phosphate,pH 7.4,but sigmoidal kinetics(with an apparent intercept)in low ionic strength buffers and at physiological phosphate concentrations.In low ionic strength buffers both the heme domain and the full-length enzyme show complex palmitate binding behavior that indicates a minimum of four fatty acid binding sites,with high cooperativity for the binding of the fourth palmitate molecule,and the full-length enzyme showing tighter palmitate binding than the heme domain.The first flavin-to-heme electron transfer is faster for laurate,myristate and palmitate in 100 mmol/L phosphate than in 50mmol/L Tris(pH 7.4),yet each substrate induces similar high-spin heme content.For palmitate in low phosphate buffer concentrations,the rate constant of the first electron transfer is much larger than kcat.The results suggest that phosphate has a specific effect in promoting the first electron transfer step,and that P450_(BM3) could modulate Bacillus membrane morphology and fluidity via palmitate oxidation in response to the external phosphate concentration.展开更多
British Prime Minister Keir Starmer’s visit to China underscores economic cooperation and strategic stability amid global uncertainties.U.K.Prime Minister Keir Starmer’s visit to China in January marks a significant...British Prime Minister Keir Starmer’s visit to China underscores economic cooperation and strategic stability amid global uncertainties.U.K.Prime Minister Keir Starmer’s visit to China in January marks a significant shift of Britain toward a more pragmatic and stability-oriented approach in Sino-British relations.After years of political tensions and limited high-level engagement,this trip underscores London’s intent to rebuild ties based on mutual economic and strategic interests.展开更多
The year 2025 marks both the 25th anniversary of the Forum on China-Africa Cooperation(FOCAC)and the first year of implementation of the outcomes of the 2024 FOCAC Beijing Summit.Throughout the year,China has supporte...The year 2025 marks both the 25th anniversary of the Forum on China-Africa Cooperation(FOCAC)and the first year of implementation of the outcomes of the 2024 FOCAC Beijing Summit.Throughout the year,China has supported Africa in addressing historical injustices at diplomatic and political levels and firmly backed South Africa in hosting the G20 Leaders’Summit,further deepening China-Africa strategic mutual trust.展开更多
Metal ion homeostasis plays a pivotal role in maintaining cellular functions,and its disruption can initiate regulated cell death pathways.Despite its therapeutic potential,metal ion therapy for breast cancer has been...Metal ion homeostasis plays a pivotal role in maintaining cellular functions,and its disruption can initiate regulated cell death pathways.Despite its therapeutic potential,metal ion therapy for breast cancer has been hampered by inefficient ion delivery and the intrinsic resistance mechanisms of cancer cells.In this work,a cuproptosis amplifier of copper-telaglenastat coordinate(denoted as Cu-CB) is developed to trigger cell ferroptosis for synergistic breast cancer treatment.Telaglenastat(CB-839),a glutaminase inhibitor,is identified as an effective copper ionophore that facilitates the formation of Cu-CB.Specially,Cu-CB can promote the aggregation of lipoylated proteins to initiate cuproptosis,while also inhibiting glutathione(GSH) synthesis and downregulating glutathione peroxidase 4(GPX4) to trigger ferroptosis.The interplay between these cuproptosis and apoptosis pathways,mediated by Cu-CB,significantly amplifies reactive oxygen species(ROS) production and lipid peroxidation,culminating in the synergistic suppression of breast cancer.Both in vitro and in vivo studies validate the superior antitumor effects of Cu-CB through the induction of cuproptosis and ferroptosis,which may provide a new insight for metal ion delivery systems and metal ion-based tumor therapies.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 recent signing of a partnership agreement between China and Cameroon aims to promote excellence in higher education A colourful ceremony marking yet another milestone in burgeoning China-Cameroon cooperation was h...The recent signing of a partnership agreement between China and Cameroon aims to promote excellence in higher education A colourful ceremony marking yet another milestone in burgeoning China-Cameroon cooperation was held on 13 January in Yaoundé.展开更多
Experts and officials shared their insights on poverty reduction cooperation and sustainable development during the 2025 International Seminar on Global Poverty Reduction Partnerships.
CHINA Auto Output,Sales Hit New Highs China’s automobile production and sales both exceeded 34 million units in 2025,setting a new record,o!ering new cooperation opportunities and helping to establish a global win-wi...CHINA Auto Output,Sales Hit New Highs China’s automobile production and sales both exceeded 34 million units in 2025,setting a new record,o!ering new cooperation opportunities and helping to establish a global win-win ecosystem in this sector.Total auto output reached 34.531 million units in 2025,up 10.4 percent compared with the 2024 level,while sales rose 9.4 percent year on year to 34.4 million units,according to the China Association of Automobile Manufacturers(CAAM).展开更多
The final and award ceremony of the International Standardization Youth Star Competition 2025 were held in Qingdao on November 22-23.The competition attracted 236 teams nationwide who demonstrated great enthusiasm for...The final and award ceremony of the International Standardization Youth Star Competition 2025 were held in Qingdao on November 22-23.The competition attracted 236 teams nationwide who demonstrated great enthusiasm for participating in the standardization undertaking.The competition followed the mode of“the industry puts forward questions,and the academia provides solutions”.Shandong Port Group Co.,Ltd.,Contemporary Amperex Technology Co.,Ltd.(CATL),Huawei Technologies Co.,Ltd.,and Beijing Zhongbiaolvjian Engineering Design and Research Institute Co.,Ltd.set up themed tracks respectively,and competitors developed standard proposals for the corresponding themes.展开更多
As a major source of freshwater in Central Asia,Tajikistan is endowed with abundant glaciers and water resources.However,the country faces multiple challenges,including accelerated glacier retreat,complex inter-govern...As a major source of freshwater in Central Asia,Tajikistan is endowed with abundant glaciers and water resources.However,the country faces multiple challenges,including accelerated glacier retreat,complex inter-government water resource management,and inefficient water use.Existing research has predominantly focused on individual hydrological processes,such as glacier retreat,snow cover change,or transboundary water issues,but it has yet to fully capture the overall complexity of water system.Tajikistan’s water system functions as an integrated whole from mountain runoff to downstream supply,but a comprehensive study of its water resource has yet to be conducted.To address this research gap,this study systematically examined the status,challenges,and sustainable management strategies of Tajikistan’s water resources based on a literature review,remote sensing data analysis,and case studies.Despite Tajikistan’s relative abundance of water resources,global warming is accelerating glacier melting and altering the hydrological cycles,which have resulted in unstable runoff patterns and heightened risks of extreme events.In Tajikistan,outdated infrastructure and poor management are primary causes of low water-use efficiency in the agricultural sector,which accounts for 85.00%of the total water withdrawals.At the governance level,Tajikistan faces challenges in balancing the water-energy-food nexus and transboundary water resource issues.To address these issues,this study proposes core paths for Tajikistan to achieve sustainable water resource management,such as accelerating technological innovation,promoting water-saving agricultural technologies,improving water resource utilization efficiency,and establishing a community participation-based comprehensive management framework.Additionally,strengthening cross-border cooperation and improving real-time monitoring systems have been identified as critical steps to advance sustainable water resource utilization and evidence-based decision-making in Tajikistan and across Central Asia.展开更多
Educational cooperation,as the cornerstone and vanguard of people-to-people exchanges and practical cooperation between China and Africa,holds irreplaceable strategic significance for enhancing the quality of Africa&#...Educational cooperation,as the cornerstone and vanguard of people-to-people exchanges and practical cooperation between China and Africa,holds irreplaceable strategic significance for enhancing the quality of Africa's human capital and accelerating its structural transformation and modernization process.This paper employs“demand–supply–adaptation”as its core analytical framework and aims to systematically explore how the educational cooperation between China and Africa can serve Africa's goal of modernization more precisely and effectively.First,through reviewing and analyzing the domestic and international research literature,this paper clarifies the focus,paradigms,and shortcomings of existing research,identifying the knowledge contribution of this study.Second,utilizing detailed macro-level data,case studies,and comparative research methods,it comprehensively presents the multidimensional status,structural characteristics,and development trends of China–Africa educational cooperation in areas such as student exchanges,cooperative education,vocational and technical training,language and cultural exchange,and emerging digital education.This paper also deeply analyzes the pressing and specific demands placed on the education system by Africa's modernization development across key dimensions like economic diversification,industrialization,agricultural modernization,social governance upgrading,and digital transformation.Third,based on the cooperative principle of“Africa's needs and China's strengths,”this paper innovatively proposes systematic countermeasures and suggestions for constructing new,multi-level,high-quality,sustainable,and future-oriented pathways for China–Africa educational cooperation:(a)promoting the strategic focus of cooperation to extend from“hard infrastructure”support to empowering“soft infrastructure”;(b)deepening the integration of industry and education and school–enterprise collaboration to precisely align with Africa's industrial development needs;vigorously developing digital education and jointly building a smart education ecosystem to help Africa bridge the digital divide;(c)improving an evidence-based,third-party evaluation system for cooperative effectiveness and a full-process quality assurance system;and(d)promoting the collaborative participation of multiple actors including governments,schools,enterprises,think tanks,and social organizations to build a new cooperative pattern of coconstruction,co-governance,and shared benefits.展开更多
The advent of sixth-generation(6G)networks introduces unprecedented challenges in achieving seamless connectivity,ultra-low latency,and efficient resource management in highly dynamic environments.Although fifth-gener...The advent of sixth-generation(6G)networks introduces unprecedented challenges in achieving seamless connectivity,ultra-low latency,and efficient resource management in highly dynamic environments.Although fifth-generation(5G)networks transformed mobile broadband and machine-type communications at massive scales,their properties of scaling,interference management,and latency remain a limitation in dense high mobility settings.To overcome these limitations,artificial intelligence(AI)and unmanned aerial vehicles(UAVs)have emerged as potential solutions to develop versatile,dynamic,and energy-efficient communication systems.The study proposes an AI-based UAV architecture that utilizes cooperative reinforcement learning(CoRL)to manage an autonomous network.The UAVs collaborate by sharing local observations and real-time state exchanges to optimize user connectivity,movement directions,allocate power,and resource distribution.Unlike conventional centralized or autonomous methods,CoRL involves joint state sharing and conflict-sensitive reward shaping,which ensures fair coverage,less interference,and enhanced adaptability in a dynamic urban environment.Simulations conducted in smart city scenarios with 10 UAVs and 50 ground users demonstrate that the proposed CoRL-based UAV system increases user coverage by up to 10%,achieves convergence 40%faster,and reduces latency and energy consumption by 30%compared with centralized and decentralized baselines.Furthermore,the distributed nature of the algorithm ensures scalability and flexibility,making it well-suited for future large-scale 6G deployments.The results highlighted that AI-enabled UAV systems enhance connectivity,support ultra-reliable low-latency communications(URLLC),and improve 6G network efficiency.Future work will extend the framework with adaptive modulation,beamforming-aware positioning,and real-world testbed deployment.展开更多
基金the support from the National Natural Science Foundation of China (No. 21875184)the Natural Science Foundation of Shaanxi Province (No. 2022JC-10)Youth Talent of Shaanxi “TeZhi” Program。
文摘An in-depth analysis on the cooperativity of intermolecular interactions including hydrogen bonding andπ-π stacking in 1,3,5-triamino-2,4,6-trinitrobenzene(TATB) crystal was studied. Two quantities, cooperativity rate and energy, were defined to evaluate the nature and strength of cooperativity in a series of clusters diverging from 1D to 3D prototypes. The origin and mechanism of the cooperative effect were settled to demonstrate that the nature of cooperativity is determined by whether the non-covalent interactions compete or promote with each other, which is manifested by the changing trend of electron transfer. There exists obvious cooperative effect in intra-layer and inter-layer structures as they own the equivalent non-covalent interactions, while anti-cooperative effect is also observed if two interactions correlate with each other. On the whole, in the process of crystal formation, the apparent cooperativity is the check and balance of the two effects, which is capable to support a global interaction among all of molecules and contribute to the stabilization of system. Based on the results, one may get a new insight to understand the relationship between non-covalent interactions and low impact sensitivity.
文摘Molecular dynamics method was employed to study the binding energies of the selected crystal planes of the 1,3,5,7-tetranitro-1,3,5,7-tetrazacyclooctane（HMX）/1,3-dimethyl-2-imidazolidinone（DMI） cocrystal in different molecular molar ratios. The mechanical properties were estimated in different molar ratios. Solvent effects were evaluated and the cooperativity effects were discussed in the HMX···HF···DMI ternary by using the M06-2x/6-311＋G（2df,2p） and MP2（full）/6-311＋G（2df,2p） methods. The results indicate that the substituted patterns（020） and（100） own the highest binding energies. The stabilities of cocrystals in the 1：1 and 2：1 ratios are the greatest, and thus the HMX/DMI cocrystals prefer cocrystallizing in the 1：1 and 2：1 molar ratios, which have good mechanical properties. The sensitivity change of cocrystal originates from not only the formation of intermolecular interaction but also the increment of bond dissociation energy of the N–NO2 bond. The cooperativity effect appears in the linear complex while the anti-cooperativity effect is found in the cyclic system. DMI binding to HMX is not energetically and structurally favored in the presence of HF. This is perhaps the reason that the solvent with large dielectric constant weakens the stability of the HMX/DMI cocrystals. Therefore, the solvents with low dielectric constants should be chosen in the preparation of HMX/DMI cocrystals.
基金support by a Foundation for the Author of National Excellent Doctoral Dissertation of China(No.FANEDD,200759)the Outstanding Young Scientist Foundation of NSFC(No.20625414)
文摘A bifunctional heterogeneous catalyst containing two mutually incompatible acidic and basic sites, which exhibits cooperative catalytic behavior in the aldol condensation of acetone and various aldehydes, was synthesized by postgrafting of 1,5,7- triazabicyclo[4.4.0] dec-5-ene （TBD, a sterically hindered organic base） onto AI-MCM-41 molecular sieve. 2009 Xiao Bing Lu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
文摘Thermodynamic data were determined for the reversible binding of O 2 to two compounds of dicobalt(II) di(meso tetra phenyl)porphyrin derivatives with different lengths of diamidoaliphatic bridge (abbreviated to Co 2PP 8 and Co 2PP 4) in N,N dimethylformamide at room temperature. The partial pressure of dioxygen necessary for half oxygenation ( P 1/2 ) and Hill coefficient ( n ) at 298 K were determined as follows: P 1/2 =54.2 kPa, n =2.0 for Co 2PP 8 and P 1/2 =6.8 kPa, n =1.8 for Co 2PP 4,respectively. The rate equations of reversible oxygen binding by Co 2PP 8 were determined and the reaction path was proposed. The results of thermodynamic and kinetic studies indicate that there exists strong cooperative effect during oxygenation of the compounds. The ESR observation reveals that the dioxygen complexes formed in the solutions are of superoxo (Co O - 2) type.
文摘Here we examine the findings obtained for disaccharide/water mixtures near glass transition that involves cooperative relaxation features on kinetic by viscosity and on thermodynamic behaviour by neutron scattering. Then to address cooperative phenomena that mitigate the Debye-Waller behaviour we invoke Adam-Gibbs’ idea of a cooperative rearranging region. Neutron results suggest that the excess mean square displacement behaves as free volume and is closely connected to an elementary step of the structural relaxation. Then viscosity data evidence a breakdown of the Einstein-Debye relation, decoupling attributed to the intermolecular cooperativity.
文摘The Arabidopsis phosphoinositide kinases PI4Kβ1 and PIP5K5 have been implicated in the control of directional vesicle trafficking underlying polar tip growth in pollen tubes. PI4Kβ1 and PIP5K5 catalyze key consecutive steps of phosphoinositide conversion, and it appears obvious that phosphatidylinositol-4-phosphate formed by PI4Kβ1 might act as a substrate for phosphatidylinositol-4,5-bisphosphate formation by PIP5K5. However, this hypothesis has not been experimentally addressed and distinct localization patterns of PI4Kβ1, PIP5K5, and also PI-synthases （PIS） generating phosphatidylinositol suggest additional complexity. Here, the synergistic functionality of enzymes of phosphoinositide conversion was assessed. In tobacco and Arabidopsis pollen tubes, phosphoinositides influence the apical secretion of pectin, and increased pectin deposition results in characteristic morphological alterations. Catalytically active and dominant negative variants of PI4Kβ1 and PIP5K5 were systematically co-expressed in tobacco pollen tubes and the incidence of morphologies related to enhanced pectin secretion was evaluated. The data support a proposed functional interplay of PI4Kβ1 and PIP5K5 at the trans-Golgi network, mediating directional vesicle trafficking. Co-expression experiments additionally including PIS isoforms, PIS1 or PIS2, indicate that pectin secretion is synergistically mediated by PI4Kβ1 and PIPSK5 acting on Ptdlns formed by PIS2 rather than PIS1. Possible ramifications for the preferential channeling of phosphoinositide intermediates between particular isoforms of PI pathway enzymes are discussed.
基金Supported by the Shenzhen Key Laboratory of Control Theory and Intelligent Systems (ZDSYS20220330161800001)the National Natural Science Foundation of China (62303207)the Guangdong Basic and Applied Basic Research Foundation (2024A1515010725)。
文摘This paper studies cooperative robust parallel operation of multiple actuators over an undirected communication graph.The plant is modeled as an uncertain linear system,and the actuators are linear and identical.Based on the internal model principle,a distributed dynamic output feedback control law is proposed to achieve both robust output regulation of the closed-loop system and plant input sharing among the actuators.A practical example of five motors cooperatively driving an uncertain shaft under an external load torque is presented to show the effectiveness of the proposed control law.
基金supported by grants from the Natural Sciences and Engineering Research Council(NSERC)Canada,and the Rhodes Trust(JY)the Higher Educational Funding Council for England.
文摘Fatty acid binding and oxidation kinetics for wild type P450_(BM3)(CYP102A1)from Bacillus megaterium have been found to display chain length-dependent homotropic behavior.Laurate and 13-methyl-myristate display Michaelis-Menten behavior while there are slight deviations with myristate at low ionic strengths.Palmitate shows Michaelis-Menten kinetics and hyperbolic binding behavior in 100 mmol/L phosphate,pH 7.4,but sigmoidal kinetics(with an apparent intercept)in low ionic strength buffers and at physiological phosphate concentrations.In low ionic strength buffers both the heme domain and the full-length enzyme show complex palmitate binding behavior that indicates a minimum of four fatty acid binding sites,with high cooperativity for the binding of the fourth palmitate molecule,and the full-length enzyme showing tighter palmitate binding than the heme domain.The first flavin-to-heme electron transfer is faster for laurate,myristate and palmitate in 100 mmol/L phosphate than in 50mmol/L Tris(pH 7.4),yet each substrate induces similar high-spin heme content.For palmitate in low phosphate buffer concentrations,the rate constant of the first electron transfer is much larger than kcat.The results suggest that phosphate has a specific effect in promoting the first electron transfer step,and that P450_(BM3) could modulate Bacillus membrane morphology and fluidity via palmitate oxidation in response to the external phosphate concentration.
文摘British Prime Minister Keir Starmer’s visit to China underscores economic cooperation and strategic stability amid global uncertainties.U.K.Prime Minister Keir Starmer’s visit to China in January marks a significant shift of Britain toward a more pragmatic and stability-oriented approach in Sino-British relations.After years of political tensions and limited high-level engagement,this trip underscores London’s intent to rebuild ties based on mutual economic and strategic interests.
文摘The year 2025 marks both the 25th anniversary of the Forum on China-Africa Cooperation(FOCAC)and the first year of implementation of the outcomes of the 2024 FOCAC Beijing Summit.Throughout the year,China has supported Africa in addressing historical injustices at diplomatic and political levels and firmly backed South Africa in hosting the G20 Leaders’Summit,further deepening China-Africa strategic mutual trust.
基金supported by the National Natural Science Foundation of China (Nos.82302355,32371394)Guangdong Basic and Applied Basic Research Foundation (No.2023A1515012628)+1 种基金the Characteristic Innovation Projects of General Colleges and Universities in Guangdong Province (No.2024KTSCX120)the Science and Technology Program of Guangzhou (Nos.2024A04J3324,2024A03J0078)。
文摘Metal ion homeostasis plays a pivotal role in maintaining cellular functions,and its disruption can initiate regulated cell death pathways.Despite its therapeutic potential,metal ion therapy for breast cancer has been hampered by inefficient ion delivery and the intrinsic resistance mechanisms of cancer cells.In this work,a cuproptosis amplifier of copper-telaglenastat coordinate(denoted as Cu-CB) is developed to trigger cell ferroptosis for synergistic breast cancer treatment.Telaglenastat(CB-839),a glutaminase inhibitor,is identified as an effective copper ionophore that facilitates the formation of Cu-CB.Specially,Cu-CB can promote the aggregation of lipoylated proteins to initiate cuproptosis,while also inhibiting glutathione(GSH) synthesis and downregulating glutathione peroxidase 4(GPX4) to trigger ferroptosis.The interplay between these cuproptosis and apoptosis pathways,mediated by Cu-CB,significantly amplifies reactive oxygen species(ROS) production and lipid peroxidation,culminating in the synergistic suppression of breast cancer.Both in vitro and in vivo studies validate the superior antitumor effects of Cu-CB through the induction of cuproptosis and ferroptosis,which may provide a new insight for metal ion delivery systems and metal ion-based tumor therapies.
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 recent signing of a partnership agreement between China and Cameroon aims to promote excellence in higher education A colourful ceremony marking yet another milestone in burgeoning China-Cameroon cooperation was held on 13 January in Yaoundé.
文摘Experts and officials shared their insights on poverty reduction cooperation and sustainable development during the 2025 International Seminar on Global Poverty Reduction Partnerships.
文摘CHINA Auto Output,Sales Hit New Highs China’s automobile production and sales both exceeded 34 million units in 2025,setting a new record,o!ering new cooperation opportunities and helping to establish a global win-win ecosystem in this sector.Total auto output reached 34.531 million units in 2025,up 10.4 percent compared with the 2024 level,while sales rose 9.4 percent year on year to 34.4 million units,according to the China Association of Automobile Manufacturers(CAAM).
文摘The final and award ceremony of the International Standardization Youth Star Competition 2025 were held in Qingdao on November 22-23.The competition attracted 236 teams nationwide who demonstrated great enthusiasm for participating in the standardization undertaking.The competition followed the mode of“the industry puts forward questions,and the academia provides solutions”.Shandong Port Group Co.,Ltd.,Contemporary Amperex Technology Co.,Ltd.(CATL),Huawei Technologies Co.,Ltd.,and Beijing Zhongbiaolvjian Engineering Design and Research Institute Co.,Ltd.set up themed tracks respectively,and competitors developed standard proposals for the corresponding themes.
基金supported by the National Natural Science Foundation of China(W2412135)the Youth Innovation Promotion Association of the Chinese Academy of Sciences.
文摘As a major source of freshwater in Central Asia,Tajikistan is endowed with abundant glaciers and water resources.However,the country faces multiple challenges,including accelerated glacier retreat,complex inter-government water resource management,and inefficient water use.Existing research has predominantly focused on individual hydrological processes,such as glacier retreat,snow cover change,or transboundary water issues,but it has yet to fully capture the overall complexity of water system.Tajikistan’s water system functions as an integrated whole from mountain runoff to downstream supply,but a comprehensive study of its water resource has yet to be conducted.To address this research gap,this study systematically examined the status,challenges,and sustainable management strategies of Tajikistan’s water resources based on a literature review,remote sensing data analysis,and case studies.Despite Tajikistan’s relative abundance of water resources,global warming is accelerating glacier melting and altering the hydrological cycles,which have resulted in unstable runoff patterns and heightened risks of extreme events.In Tajikistan,outdated infrastructure and poor management are primary causes of low water-use efficiency in the agricultural sector,which accounts for 85.00%of the total water withdrawals.At the governance level,Tajikistan faces challenges in balancing the water-energy-food nexus and transboundary water resource issues.To address these issues,this study proposes core paths for Tajikistan to achieve sustainable water resource management,such as accelerating technological innovation,promoting water-saving agricultural technologies,improving water resource utilization efficiency,and establishing a community participation-based comprehensive management framework.Additionally,strengthening cross-border cooperation and improving real-time monitoring systems have been identified as critical steps to advance sustainable water resource utilization and evidence-based decision-making in Tajikistan and across Central Asia.
文摘Educational cooperation,as the cornerstone and vanguard of people-to-people exchanges and practical cooperation between China and Africa,holds irreplaceable strategic significance for enhancing the quality of Africa's human capital and accelerating its structural transformation and modernization process.This paper employs“demand–supply–adaptation”as its core analytical framework and aims to systematically explore how the educational cooperation between China and Africa can serve Africa's goal of modernization more precisely and effectively.First,through reviewing and analyzing the domestic and international research literature,this paper clarifies the focus,paradigms,and shortcomings of existing research,identifying the knowledge contribution of this study.Second,utilizing detailed macro-level data,case studies,and comparative research methods,it comprehensively presents the multidimensional status,structural characteristics,and development trends of China–Africa educational cooperation in areas such as student exchanges,cooperative education,vocational and technical training,language and cultural exchange,and emerging digital education.This paper also deeply analyzes the pressing and specific demands placed on the education system by Africa's modernization development across key dimensions like economic diversification,industrialization,agricultural modernization,social governance upgrading,and digital transformation.Third,based on the cooperative principle of“Africa's needs and China's strengths,”this paper innovatively proposes systematic countermeasures and suggestions for constructing new,multi-level,high-quality,sustainable,and future-oriented pathways for China–Africa educational cooperation:(a)promoting the strategic focus of cooperation to extend from“hard infrastructure”support to empowering“soft infrastructure”;(b)deepening the integration of industry and education and school–enterprise collaboration to precisely align with Africa's industrial development needs;vigorously developing digital education and jointly building a smart education ecosystem to help Africa bridge the digital divide;(c)improving an evidence-based,third-party evaluation system for cooperative effectiveness and a full-process quality assurance system;and(d)promoting the collaborative participation of multiple actors including governments,schools,enterprises,think tanks,and social organizations to build a new cooperative pattern of coconstruction,co-governance,and shared benefits.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(RS-2025-00559546)supported by the IITP(Institute of Information&Coummunications Technology Planning&Evaluation)-ITRC(Information Technology Research Center)grant funded by the Korea government(Ministry of Science and ICT)(IITP-2025-RS-2023-00259004).
文摘The advent of sixth-generation(6G)networks introduces unprecedented challenges in achieving seamless connectivity,ultra-low latency,and efficient resource management in highly dynamic environments.Although fifth-generation(5G)networks transformed mobile broadband and machine-type communications at massive scales,their properties of scaling,interference management,and latency remain a limitation in dense high mobility settings.To overcome these limitations,artificial intelligence(AI)and unmanned aerial vehicles(UAVs)have emerged as potential solutions to develop versatile,dynamic,and energy-efficient communication systems.The study proposes an AI-based UAV architecture that utilizes cooperative reinforcement learning(CoRL)to manage an autonomous network.The UAVs collaborate by sharing local observations and real-time state exchanges to optimize user connectivity,movement directions,allocate power,and resource distribution.Unlike conventional centralized or autonomous methods,CoRL involves joint state sharing and conflict-sensitive reward shaping,which ensures fair coverage,less interference,and enhanced adaptability in a dynamic urban environment.Simulations conducted in smart city scenarios with 10 UAVs and 50 ground users demonstrate that the proposed CoRL-based UAV system increases user coverage by up to 10%,achieves convergence 40%faster,and reduces latency and energy consumption by 30%compared with centralized and decentralized baselines.Furthermore,the distributed nature of the algorithm ensures scalability and flexibility,making it well-suited for future large-scale 6G deployments.The results highlighted that AI-enabled UAV systems enhance connectivity,support ultra-reliable low-latency communications(URLLC),and improve 6G network efficiency.Future work will extend the framework with adaptive modulation,beamforming-aware positioning,and real-world testbed deployment.
