Potassium ion batteries(PIBs)are emerging as potential next-generation energy storage systems on account of their low cost and high theoretical energy density.Nevertheless,they also face challenges of low specific cap...Potassium ion batteries(PIBs)are emerging as potential next-generation energy storage systems on account of their low cost and high theoretical energy density.Nevertheless,they also face challenges of low specific capacity and suboptimal cycling stability.Herein,we synthesize a cocoon-like P3-type K_(0.5)Mn_(0.7)Ni_(0.3)O_(2)(KMNO)cathode material by a self-template method.The KMNO cocoons possess a hierarchical layered architecture composed of nanoparticle stacking,which can accelerate the transport kinetics of potassium ions,mitigate the stress caused by K^(+)intercalation and deintercalation,and improve structural stability.In addition,Ni can not only alleviate the Jahn-Teller distortion and suppress the phase transition to stabilize the structure,but also act as an electrochemically active element,providing the capacity of two electrons from Ni2+to Ni4+.Combining the advantages of structure and nickel substitution,the P3-type KMNO cocoons are used for electrochemical performance testing of PIB cathodes,delivering an excellent rate capability of 57.1 m A h g^(-1)at 500 m A g^(-1)and a remarkable cycling stability of 77.0%over 300 cycles at 100 m A g^(-1).Impressively,the KMNO cocoons//pitch-derived soft carbon assembled full battery exhibits superior electrochemical performance with a reversible capacity of 79.7 m A h g^(-1)at 50 m A g^(-1).Moreover,ex-situ XRD also further reveals a solid solution phase reaction with a volume change of only 1.46%.This work furnishes a suitable approach to fabricating highperformance layered oxide cathodes for PIBs with outstanding cycling stability and rate capability.展开更多
This paper investigates the Quality of Experience(QoE)oriented channel access anti-jamming problem in 5th Generation Mobile Communication(5G)ultra-dense networks.Firstly,considering that the 5G base station adopts bea...This paper investigates the Quality of Experience(QoE)oriented channel access anti-jamming problem in 5th Generation Mobile Communication(5G)ultra-dense networks.Firstly,considering that the 5G base station adopts beamforming technology,an anti-jamming model under Space Division Multiple Access(SDMA)conditions is proposed.Secondly,the confrontational relationship between users and the jammer is formulated as a Stackelberg game.Besides,to achieve global optimization,we design a local cooperation mechanism for users and formulate the cooperation and competition among users as a local altruistic game.By proving that the local altruistic game is an Exact Potential Game(EPG),we further prove the existence of pure strategy Nash Equilibrium(NE)among users and Stackelberg Equilibrium(SE)between users and jammer.Thirdly,to obtain the equilibrium solutions of the proposed games,we propose an anti-jamming channel selection algorithm and improve its convergence speed through heterogeneous learning parameters.The simulation results validate the convergence and effectiveness of the proposed algorithm.Compared with the throughput optimization scheme,our proposed scheme obtain a greater network satisfaction rate.Finally,we also analyze user fairness changes during the algorithm convergence process and get some interesting conclusions.展开更多
The Wnt/β-catenin signaling pathway is the main target of tooth regeneration regulation.Treatment of cells with AZD2858 stimulates the Wnt/β-catenin signaling pathway,yet the function of this pathway in tooth regene...The Wnt/β-catenin signaling pathway is the main target of tooth regeneration regulation.Treatment of cells with AZD2858 stimulates the Wnt/β-catenin signaling pathway,yet the function of this pathway in tooth regeneration remains unclear.Here,we found that AZD2858 promotes the accumulation ofβ-catenin in the nuclei of stem cells from the apical papilla(SCAPs)and enhances cell proliferation.Single-cell sequencing was performed on SCAPs treated with AZD2858.Eight clusters were identified,namely SCAPs-CNTNAP2,SCAPs-DTL,SCAPs-MYH11,SCAPs-MKI67,SCAPs-CXCL8,SCAPs-TPM2,SCAPs-IFIT2 and SCAPs-NEK10.The pseudo-time trajectory analysis showed that AZD2858 enhanced the evolution of SCAPs from SCAPs-TMP2 clusters to SCAPs-MYH11,SCAPs-CNTNAPs and SCAPs-NEK10 clusters via up-regulation of PRKCA,SMURF2,MAGI2,RBMS3,EXT1,CAMK2D,PLCB4,and PLCB1.These results demonstrate that AZD2858 enhances the proliferation of SCAPs-TPM2 cluster by activating the non-canonical Wnt/β-catenin signaling pathway.展开更多
Although chalcogenide anodes possess higher potassium storage capacity than intercalated-based graphite,their drastic volume change and the irreversible electrochemical reactions still hinder the effective electron/io...Although chalcogenide anodes possess higher potassium storage capacity than intercalated-based graphite,their drastic volume change and the irreversible electrochemical reactions still hinder the effective electron/ion transfer during the potassiation/depotassiation process.To solve the above problems,this article proposes the synthesis of a lamellar nanostructure where graphene nanosheets are embedded with SnSb_(2)Se_(4)nanoparticles(SnSb_(2)Se_(4)/GNS).In the product,fine monodisperse SnSb_(2)Se_(4)nanoparticles are coupled with graphene nanosheets to form a porous network framework,which can effectively mitigate the drastic volume changes during electrode reactions and guarantee efficient potassium-ion storage through the synergistic interactions among multiple elements.Various electrochemical analyses prove that SnSb_(2)Se_(4)inherits the advantages of the binary Sb2Se3 and SnSe while avoiding their disadvantages,confirming the synergistic effect of the ternary–chalcogenide system.When tested for potassium storage,the obtained composite delivers a high specific capacity of 368.5 mAh g^(-1)at 100 mA g^(-1)and a stable cycle performance of 265.8 mAh g^(-1)at 500 mA g^(-1)over 500 cycles.Additionally,the potassium iron hexacyanoferrate cathode and the SnSb_(2)Se_(4)/GNS anode are paired to fabricate the potassium-ion full cell,which shows excellent cyclic stability.In conclusion,this strategy employs atomic doping and interface interaction,which provides new insights for the design of high-rate electrode materials.展开更多
Atherosclerotic cardiovascular disease(ASCVD)includes a group of disorders of the heart and blood vessels and accounts for major morbidity and premature death worldwide.Periodontitis is a chronic inflammatory disease ...Atherosclerotic cardiovascular disease(ASCVD)includes a group of disorders of the heart and blood vessels and accounts for major morbidity and premature death worldwide.Periodontitis is a chronic inflammatory disease with the gradual destruction of supporting tissues around the teeth,including gingiva,periodontal ligament,alveolar bone,and cementum.Periodontitis has been found to potentially increase the risk of ASCVD.Generally,oral microorganisms and inflammation are the major factors for periodontitis to the incidence of ASCVD.Recently,evidence has shown that the loss of masticatory function is another important factor of periodontitis to the incidence of ASCVD.In this review,we illustrate the recent finding of the relationship between periodontitis and ASCVD,from a microscale perspective-oral microorganisms,inflammation,and tooth loss.With the high prevalence of periodontitis,it is important to add oral therapy as a regular ASCVD prevention strategy.Regular dental visits could be a helpful strategy for ASCVD patients or general medical practitioners.展开更多
Modulation bandwidth enhancement in a directly modulated two-section distributed feedback(TS-DFB)laser based on a detuned loading effect is investigated and experimentally demonstrated.The results show that the 3-dB b...Modulation bandwidth enhancement in a directly modulated two-section distributed feedback(TS-DFB)laser based on a detuned loading effect is investigated and experimentally demonstrated.The results show that the 3-dB bandwidth of the TS-DFB laser is increased to 17.6 GHz and that chirp parameter can be reduced to 2.24.Compared to the absence of a detuned loading effect,there is a 4.6 GHz increase and a 2.45 reduction,respectively.After transmitting a 10 Gb/s non-return-to-zero(NRZ)signal through a 5-km fiber,the modulation eye diagram still achieves a large opening.Eight-channel laser arrays with precise wavelength spacing are fabricated.Each TS-DFB laser in the array has side mode suppression ratios(SMSR)>49.093 dB and the maximum wavelength residual<0.316 nm.展开更多
This paper investigates the channel diversity problem in high frequency(HF) communication systems. Due to the limited HF spectrum resources, a HF communication system with shared channels is considered, where each use...This paper investigates the channel diversity problem in high frequency(HF) communication systems. Due to the limited HF spectrum resources, a HF communication system with shared channels is considered, where each user equipment(UE) has individual communication demand. In order to maximize the communication probability of the whole system, a matching-potential game framework is designed. In detail, the channel diversity problem is decomposed into two sub-problems. One is channel-transmitter matching problem, which can be formulated as a many-to-one matching game. The other is the transmitter allocation problem which decides the transmission object that each transmitter communicates with under channel-transmitter matching result, and this sub-problem can be modeled as a potential game. A multiple round stable matching algorithm(MRSMA) is proposed, which obtains a stable matching result for the first sub-problem, and a distributed BR-based transmitter allocation algorithm(DBRTAA) is designed to reach Nash Equilibrium(NE) of the second sub-problem. Simulation results verify the effectiveness and superiority of the proposed method.展开更多
This paper investigates the anti-jamming communication scenario where an intelligent reflecting surface(IRS)is mounted on the unmanned aerial vehicle(UAV)to resist the malicious jamming attacks.Different from existing...This paper investigates the anti-jamming communication scenario where an intelligent reflecting surface(IRS)is mounted on the unmanned aerial vehicle(UAV)to resist the malicious jamming attacks.Different from existing works,we consider the dynamic deployment of IRS-UAV in the environment of the mobile user and unknown jammer.Therefore,a joint trajectory and passive beamforming optimization approach is proposed in the IRS-UAV enhanced networks.In detail,the optimization problem is firstly formulated into a Markov decision process(MDP).Then,a dueling double deep Q networks multi-step learning algorithm is proposed to tackle the complex and coupling decision-making problem.Finally,simulation results show that the proposed scheme can significantly improve the anti-jamming communication performance of the mobile user.展开更多
This paper mainly investigates the coordinated anti-jamming channel access problems in multiuser scenarios where there exists a tracking jammer who senses the spectrum and traces the channel with maximal receiving pow...This paper mainly investigates the coordinated anti-jamming channel access problems in multiuser scenarios where there exists a tracking jammer who senses the spectrum and traces the channel with maximal receiving power.To cope with the challenges brought by the tracking jammer,a multi-leader onefollower anti-jamming Stackelberg(MOAS)game is formulated,which is able to model the complex interactions between users and the tracking jammer.In the proposed game,users act as leaders,chose their channel access strategies and transmit firstly.The tracking jammer acts as the follower,whose objective is to find the optimal jamming strategy at each time slot.Besides,the existence of Stackelberg equilibriums(SEs)is proved,which means users reach Nash Equilibriums(NEs)for each jamming strategy while the jammer finds its best response jamming strategy for the current network access case.An active attraction based anti-jamming channel access(3ACA)algorithm is designed to reach SEs,where jammed users keep their channel access strategies unchanged to create access chances for other users.To enhance the fairness of the system,users will adjust their strategies and relearn after certain time slots to provide access chances for those users who sacrifice themselves to attract the tracking jammer.展开更多
As one of prussian blue analogues,Co_(3)[Co(CN)_(6)]_(2) has been explored as a promising anode material for potassium-ion batteries(PIBs) owing to its high potassium storage capacity.Unfortunately,Co_(3)[Co(CN)_(6)]_...As one of prussian blue analogues,Co_(3)[Co(CN)_(6)]_(2) has been explored as a promising anode material for potassium-ion batteries(PIBs) owing to its high potassium storage capacity.Unfortunately,Co_(3)[Co(CN)_(6)]_(2) possesses low electronic conductivity and its structure collapses easily during potassiation and depotassiation,resulting in poor rate performance and cyclic stability.To solve these problems,we develop a facile multi-step method to successfully combine uniformCo_(3)[Co(CN)_(6)]_(2) nanocubes with rGO by C-O-Co bonds.As expected,these chemcial bonds shorten the distance betweenCo_(3)[Co(CN)_(6)]_(2) and rGO to the angstrom meter level,which significantly improve the electronic conductivity ofCo_(3)[Co(CN)_(6)]_(2).Besides,the complete encapsulation ofCo_(3)[Co(CN)_(6)]_(2) nanocubes by rGO endows the structure ofCo_(3)[Co(CN)_(6)]_(2) with high stability,thus withstanding repeated insertion/extraction of potassium-ions without visible morphological and structural changes.Benefiting from the abovementioned structural advantages,the CO3 [Co(CN)6]2/rGO nanocomposite exhibits a high reversible capacity of 400.8 mAh g^(-1) at a current density of 0.1 A g^(-1),an exceptional rate capability of 115.5 mAh g^(-1) at 5 A g^(-1), and an ultralong cycle life of 231.9 mAh g^(-1) at 0.1 A g^(-1) after 1000 cycles.Additionally,the effects of different amounts of rGO and different sizes ofCo_(3)[Co(CN)_(6)]_(2) nanocubes on the potassium storage performance are also studied.This work offers an ideal route to significantly enhance the electrochemical properties of prussian blue analogues.展开更多
Potassium-ion batteries(PIBs) as a substitute for lithium-ion batteries have aroused widespread attention and have been rapidly developed. In the positive electrode materials, polyanionic compound has a high working v...Potassium-ion batteries(PIBs) as a substitute for lithium-ion batteries have aroused widespread attention and have been rapidly developed. In the positive electrode materials, polyanionic compound has a high working voltage and large reversible capacity on account of its distinct framework and the strong inducing effect of the anionic group. Herein, a KVPO_(4)F/reduced graphene oxide(KVPF/r GO) hybrid was fabricated via a simple multi-step approach as the polyanionic cathode material for PIBs. Profiting from the small size of KVPF nanoparticles and their uniform distribution in the r GO framework, the assynthesized KVPF/r GO hybrid manifests a large discharge capacity of 103.2 mAh g^(-1) with an outstanding energy density of 436.5 Wh kg^(-1). Through r GO decoration, the hybrid also demonstrates remarkable rate and cycling properties. By employing ex-situ X-ray diffraction(XRD) and X-ray photoelectron spectroscopy(XPS) techniques, the potassium storage mechanism of KVPF was clearly revealed. The facile preparation procedure and superior properties endow it great application prospects in large-scale energy storage.展开更多
Transition-metal sulfides are widely used as anodes for potassium-ion batteries(PIBs) due to their low cost and high theoretical capacity.The practical application of such materials,however,is still impeded by their i...Transition-metal sulfides are widely used as anodes for potassium-ion batteries(PIBs) due to their low cost and high theoretical capacity.The practical application of such materials,however,is still impeded by their inherent low conductivity and obvious volume change during cycling.Herein,a flexible etchassisted sulfidation strategy is reported.According to the strategy,the multicore-shell(MCS) nanocapsule structure is constructed,and then mesoporous FeS2 nanoparticles are encapsulated in the hollow carbon shell with adjustable interior space.The product,MCS-FeS2@C-20,not only features optimized inner space,but also delivers a large reversible capacity(519 mAh g^(-1) at a current density of 50 mA g^(-1)),good rate capability(107 mAh g^(-1) at a high current density of 5 A g^(-1)) and excellent cycling stability(capacity retention rate of 84.2% over 500 cycles at 0.5 A g^(-1)),making it the promising anode material for PIBs.Notably,potassium-ion full cells(MCS-FeS_(2)@C-20//K_(0.4)CoO_(2)) also show an improved potassium storage performance.展开更多
In multi-agent confrontation scenarios, a jammer is constrained by the single limited performance and inefficiency of practical application. To cope with these issues, this paper aims to investigate the multi-agent ja...In multi-agent confrontation scenarios, a jammer is constrained by the single limited performance and inefficiency of practical application. To cope with these issues, this paper aims to investigate the multi-agent jamming problem in a multi-user scenario, where the coordination between the jammers is considered. Firstly, a multi-agent Markov decision process (MDP) framework is used to model and analyze the multi-agent jamming problem. Secondly, a collaborative multi-agent jamming algorithm (CMJA) based on reinforcement learning is proposed. Finally, an actual intelligent jamming system is designed and built based on software-defined radio (SDR) platform for simulation and platform verification. The simulation and platform verification results show that the proposed CMJA algorithm outperforms the independent Q-learning method and provides a better jamming effect.展开更多
interactions,many flowers are known to display their attractive qualities,such as scent emission,flower rewards and floral vertical direction,in a rhythmic fashion.However,less is known about how plants regulate the r...interactions,many flowers are known to display their attractive qualities,such as scent emission,flower rewards and floral vertical direction,in a rhythmic fashion.However,less is known about how plants regulate the relationship between these flower traits to adapt to pollinator visiting behavior and increase reproduction success.Here we investigated the adaptive significance of the flower bending from erect to downward in Trifolium repens.We observed the flowering dynamic characteristics(changes of vertical direction of florets,flowering number,pollen grain numbers,pollen viability and stigma receptivity over time after blossom)and the factors affecting the rate of flower bending in T.repens.Then we altered the vertical direction of florets in inflorescence of different types(upright and downward),and compared the pollinator behaviors and female reproductive success.Our results showed that florets opened sequentially in inflorescence,and then bend downwards slowly after flowering.The bending speed of florets was mainly influenced by pollination,and bending angle increased with the prolongation of flowering time,while the pollen germination rate,stigma receptivity and nectar secretion has a rhythm of“lowhigh-low”during the whole period with the time going.The visiting frequency of all the four species of pollinators on upward flowers was significantly higher than that of downward flowers,and they especially prefer to visit flowers with a bending angle of 30°–60°,when the flowers was exactly of the highest flower rewards(nectar secretion and number of pollen grains),stigma receptivity and pollen germination rate.The seed set ratio and fruit set ratio of upward flowers were significantly higher than downward flowers,but significantly lower than unmanipulated flowers.Our results indicated that the T.repens could increase female and male fitness by accurate pollination.The most suitable flower angle saves pollinators’visiting energy and enables them to obtain the highest nectar rewards.This coordination between plants and pollinators maximizes the interests of them,which is a crucial factor in initiating specialized plant-pollinator relationships.展开更多
Many investigations suggest that dissimilatory arsenate-respiring prokaryotes (DARPs) play a key role in stimulating reductive mobilization of As from solid phase into groundwater,but it is not clear how environmental...Many investigations suggest that dissimilatory arsenate-respiring prokaryotes (DARPs) play a key role in stimulating reductive mobilization of As from solid phase into groundwater,but it is not clear how environmental Mn(Ⅱ) affects the DARPs-mediated reductive mobilization of arsenic.To resolve this issue,we collected soil samples from a realgar tailingsaffected area.We found that there were diverse arsenate-respiratory reductase (arr) genes in the soils.The microbial communities had high arsenate-respiring activity,and were able to efficiently stimulate the reductive mobilization of As.Compared to the microcosms without Mn(Ⅱ),addition of 10 mmol/L Mn(Ⅱ) to the microcosms led to 23.99%-251.79% increases in the microbial mobilization of As,and led to 133.3%-239.2% increases in the abundances of arr genes.We further isolated a new cultivable DARP,Bacillus sp.F11,from the arseniccontaminated soils.It completely reduced 1 mmol/L As(V) in 5 days under the optimal reaction conditions.We further found that it was able to efficiently catalyze the reductive mobilization and release of As from the solid phase;the addition of 2 mmol/L Mn(Ⅱ) led to 98.49%-248.78% increases in the F11 cells-mediated reductive mobilization of As,and70.6%-104.4% increases in the arr gene abundances.These data suggest that environmental Mn(Ⅱ) markedly increased the DARPs-mediated reductive mobilization of As in arseniccontaminated soils.This work provided a new insight into the close association between the biogeochemical cycles of arsenic and manganese.展开更多
Marine macroalgae cultivation is an important part of the effort to address climate change through carbon sinks.Gracilaria,especially Gracilaria lemaneiformis and Gracilaria lichenoides are the major macroalgae cultiv...Marine macroalgae cultivation is an important part of the effort to address climate change through carbon sinks.Gracilaria,especially Gracilaria lemaneiformis and Gracilaria lichenoides are the major macroalgae cultivated in China.This study proposes a method to assess the net carbon sink of marine macroalgae(Gracilaria)cultivation.First,the net carbon sink of Gracilaria cultivation in China is calculated based on the yield of annual cultivated Gracilaria recorded in China Fishery Statistical Yearbook from 2011 to 2020.Next,we predict the net carbon sink trend of Gracilaria cultivation from 2021 to 2030 using the autoregressive integrated moving average model(ARIMA).Finally,the potential carbon sink increase and methane reduction related to Gracilaria cultivation in China is explored through a scenario analysis.We find that the net carbon sink of Gracilaria cultivation in China was about 32.1-92.4 kilotons per year from 2011 to 2020,and shows a great annual growth trend.Moreover,the predicted net carbon sink of Gracilaria cultivation would increase to 77.8-191.4 kilotons per year from 2021 to2030,thereby could contribute considerably in the achievement of China's carbon peak goal.Under a scenario of producing ruminant green feed with additional Gracilaria cultivation,each ton of macroalgae is predicted to reduce carbon emission(i.e.,methane)by 0.33-0.68 tons.Thus,marine macroalgae cultivation might form a synergistic chain of"carbon sink increase-water purification-economy-methane reduction".This study proposes a synergistic new model that operates through marine macroalgae cultivation,economic aquaculture,and green feed production.展开更多
Solid polymer electrolytes(SPEs)by in situ polymerization are attractive due to their good interfacial contact with electrodes.Previously reported in situ polymerized SPEs,however,suffer from the low polymerization de...Solid polymer electrolytes(SPEs)by in situ polymerization are attractive due to their good interfacial contact with electrodes.Previously reported in situ polymerized SPEs,however,suffer from the low polymerization degree that causes poor mechanical strength,Li dendrite penetration,and performance decay in Li-metal batteries.Although highly polymerized SPEs are more stable than lowly polymerized ones,they are restricted by their sluggish long-chain mobility and poor ionic conductivity.In this work,a three-dimensional fibrous membrane with ion selectivity was prepared and used as a functional filler for the in situ formed SPE.The obtained SPE has high stability due to its high polymerization degree after the long-term heating process.The fibrous membrane plays a vital role in improving the SPE’s properties.The rich anion-adsorption sites on the fibrous membrane can alleviate the polarization effect and benefit a uniform current distribution at the interface.The fibrous nanostructure can efficiently interact with the polymeric matrix,providing rich hopping sites for fast Li+migration.Consequently,the obtained SPE enables a uniform Li deposition and long-term cycling performance in Li-metal batteries.This work reported an in situ formed SPE with both high polymerization degree and ionic conductivity,paving the way for designing high-performance SPEs with good comprehensive properties.展开更多
基金supported by the National Natural Science Foundation of China(22179063)。
文摘Potassium ion batteries(PIBs)are emerging as potential next-generation energy storage systems on account of their low cost and high theoretical energy density.Nevertheless,they also face challenges of low specific capacity and suboptimal cycling stability.Herein,we synthesize a cocoon-like P3-type K_(0.5)Mn_(0.7)Ni_(0.3)O_(2)(KMNO)cathode material by a self-template method.The KMNO cocoons possess a hierarchical layered architecture composed of nanoparticle stacking,which can accelerate the transport kinetics of potassium ions,mitigate the stress caused by K^(+)intercalation and deintercalation,and improve structural stability.In addition,Ni can not only alleviate the Jahn-Teller distortion and suppress the phase transition to stabilize the structure,but also act as an electrochemically active element,providing the capacity of two electrons from Ni2+to Ni4+.Combining the advantages of structure and nickel substitution,the P3-type KMNO cocoons are used for electrochemical performance testing of PIB cathodes,delivering an excellent rate capability of 57.1 m A h g^(-1)at 500 m A g^(-1)and a remarkable cycling stability of 77.0%over 300 cycles at 100 m A g^(-1).Impressively,the KMNO cocoons//pitch-derived soft carbon assembled full battery exhibits superior electrochemical performance with a reversible capacity of 79.7 m A h g^(-1)at 50 m A g^(-1).Moreover,ex-situ XRD also further reveals a solid solution phase reaction with a volume change of only 1.46%.This work furnishes a suitable approach to fabricating highperformance layered oxide cathodes for PIBs with outstanding cycling stability and rate capability.
基金supported by the National Natural Science Foundation of China under Grant No.61901523 and No.62071488.
文摘This paper investigates the Quality of Experience(QoE)oriented channel access anti-jamming problem in 5th Generation Mobile Communication(5G)ultra-dense networks.Firstly,considering that the 5G base station adopts beamforming technology,an anti-jamming model under Space Division Multiple Access(SDMA)conditions is proposed.Secondly,the confrontational relationship between users and the jammer is formulated as a Stackelberg game.Besides,to achieve global optimization,we design a local cooperation mechanism for users and formulate the cooperation and competition among users as a local altruistic game.By proving that the local altruistic game is an Exact Potential Game(EPG),we further prove the existence of pure strategy Nash Equilibrium(NE)among users and Stackelberg Equilibrium(SE)between users and jammer.Thirdly,to obtain the equilibrium solutions of the proposed games,we propose an anti-jamming channel selection algorithm and improve its convergence speed through heterogeneous learning parameters.The simulation results validate the convergence and effectiveness of the proposed algorithm.Compared with the throughput optimization scheme,our proposed scheme obtain a greater network satisfaction rate.Finally,we also analyze user fairness changes during the algorithm convergence process and get some interesting conclusions.
基金the fund of National Natural Science Foundation of China(82170951)Beijing Natural Science Foundation(7222079).
文摘The Wnt/β-catenin signaling pathway is the main target of tooth regeneration regulation.Treatment of cells with AZD2858 stimulates the Wnt/β-catenin signaling pathway,yet the function of this pathway in tooth regeneration remains unclear.Here,we found that AZD2858 promotes the accumulation ofβ-catenin in the nuclei of stem cells from the apical papilla(SCAPs)and enhances cell proliferation.Single-cell sequencing was performed on SCAPs treated with AZD2858.Eight clusters were identified,namely SCAPs-CNTNAP2,SCAPs-DTL,SCAPs-MYH11,SCAPs-MKI67,SCAPs-CXCL8,SCAPs-TPM2,SCAPs-IFIT2 and SCAPs-NEK10.The pseudo-time trajectory analysis showed that AZD2858 enhanced the evolution of SCAPs from SCAPs-TMP2 clusters to SCAPs-MYH11,SCAPs-CNTNAPs and SCAPs-NEK10 clusters via up-regulation of PRKCA,SMURF2,MAGI2,RBMS3,EXT1,CAMK2D,PLCB4,and PLCB1.These results demonstrate that AZD2858 enhances the proliferation of SCAPs-TPM2 cluster by activating the non-canonical Wnt/β-catenin signaling pathway.
基金supported by the National Natural Science Foundation of China(22075147 and 22179063)
文摘Although chalcogenide anodes possess higher potassium storage capacity than intercalated-based graphite,their drastic volume change and the irreversible electrochemical reactions still hinder the effective electron/ion transfer during the potassiation/depotassiation process.To solve the above problems,this article proposes the synthesis of a lamellar nanostructure where graphene nanosheets are embedded with SnSb_(2)Se_(4)nanoparticles(SnSb_(2)Se_(4)/GNS).In the product,fine monodisperse SnSb_(2)Se_(4)nanoparticles are coupled with graphene nanosheets to form a porous network framework,which can effectively mitigate the drastic volume changes during electrode reactions and guarantee efficient potassium-ion storage through the synergistic interactions among multiple elements.Various electrochemical analyses prove that SnSb_(2)Se_(4)inherits the advantages of the binary Sb2Se3 and SnSe while avoiding their disadvantages,confirming the synergistic effect of the ternary–chalcogenide system.When tested for potassium storage,the obtained composite delivers a high specific capacity of 368.5 mAh g^(-1)at 100 mA g^(-1)and a stable cycle performance of 265.8 mAh g^(-1)at 500 mA g^(-1)over 500 cycles.Additionally,the potassium iron hexacyanoferrate cathode and the SnSb_(2)Se_(4)/GNS anode are paired to fabricate the potassium-ion full cell,which shows excellent cyclic stability.In conclusion,this strategy employs atomic doping and interface interaction,which provides new insights for the design of high-rate electrode materials.
基金supported by the National Natural Science Foundation of China(82001067)the Innovation Research Team Project of Beijing Stomatological Hospital,Capital Medical University(CXTD202201)+2 种基金Beijing Municipal Administration of Hospitals’Youth Program(QML20191504)Scientific Research Common Program of Beijing Municipal Commission of Education(KM202110025009)Beijing Talents Fund(2018000021469G285).
文摘Atherosclerotic cardiovascular disease(ASCVD)includes a group of disorders of the heart and blood vessels and accounts for major morbidity and premature death worldwide.Periodontitis is a chronic inflammatory disease with the gradual destruction of supporting tissues around the teeth,including gingiva,periodontal ligament,alveolar bone,and cementum.Periodontitis has been found to potentially increase the risk of ASCVD.Generally,oral microorganisms and inflammation are the major factors for periodontitis to the incidence of ASCVD.Recently,evidence has shown that the loss of masticatory function is another important factor of periodontitis to the incidence of ASCVD.In this review,we illustrate the recent finding of the relationship between periodontitis and ASCVD,from a microscale perspective-oral microorganisms,inflammation,and tooth loss.With the high prevalence of periodontitis,it is important to add oral therapy as a regular ASCVD prevention strategy.Regular dental visits could be a helpful strategy for ASCVD patients or general medical practitioners.
文摘Modulation bandwidth enhancement in a directly modulated two-section distributed feedback(TS-DFB)laser based on a detuned loading effect is investigated and experimentally demonstrated.The results show that the 3-dB bandwidth of the TS-DFB laser is increased to 17.6 GHz and that chirp parameter can be reduced to 2.24.Compared to the absence of a detuned loading effect,there is a 4.6 GHz increase and a 2.45 reduction,respectively.After transmitting a 10 Gb/s non-return-to-zero(NRZ)signal through a 5-km fiber,the modulation eye diagram still achieves a large opening.Eight-channel laser arrays with precise wavelength spacing are fabricated.Each TS-DFB laser in the array has side mode suppression ratios(SMSR)>49.093 dB and the maximum wavelength residual<0.316 nm.
基金supported by the Natural Science Foundation for Distinguished Young Scholars of Jiangsu Province under Grant No. BK20160034in part by the National Natural Science Foundation of China under Grant No. 61671473 and No. 61631020in part by the Open Research Foundation of Science and Technology on Communication Networks Laboratory
文摘This paper investigates the channel diversity problem in high frequency(HF) communication systems. Due to the limited HF spectrum resources, a HF communication system with shared channels is considered, where each user equipment(UE) has individual communication demand. In order to maximize the communication probability of the whole system, a matching-potential game framework is designed. In detail, the channel diversity problem is decomposed into two sub-problems. One is channel-transmitter matching problem, which can be formulated as a many-to-one matching game. The other is the transmitter allocation problem which decides the transmission object that each transmitter communicates with under channel-transmitter matching result, and this sub-problem can be modeled as a potential game. A multiple round stable matching algorithm(MRSMA) is proposed, which obtains a stable matching result for the first sub-problem, and a distributed BR-based transmitter allocation algorithm(DBRTAA) is designed to reach Nash Equilibrium(NE) of the second sub-problem. Simulation results verify the effectiveness and superiority of the proposed method.
基金This work was supported in part by the National Natural Science Foundation of China(No.61971474,No.61771488)in part by the Beijing Nova Program under Grant Z201100006820121in part by China Postdoctoral Science Foundation Funded Project under Grant 2019T120071.
文摘This paper investigates the anti-jamming communication scenario where an intelligent reflecting surface(IRS)is mounted on the unmanned aerial vehicle(UAV)to resist the malicious jamming attacks.Different from existing works,we consider the dynamic deployment of IRS-UAV in the environment of the mobile user and unknown jammer.Therefore,a joint trajectory and passive beamforming optimization approach is proposed in the IRS-UAV enhanced networks.In detail,the optimization problem is firstly formulated into a Markov decision process(MDP).Then,a dueling double deep Q networks multi-step learning algorithm is proposed to tackle the complex and coupling decision-making problem.Finally,simulation results show that the proposed scheme can significantly improve the anti-jamming communication performance of the mobile user.
文摘This paper mainly investigates the coordinated anti-jamming channel access problems in multiuser scenarios where there exists a tracking jammer who senses the spectrum and traces the channel with maximal receiving power.To cope with the challenges brought by the tracking jammer,a multi-leader onefollower anti-jamming Stackelberg(MOAS)game is formulated,which is able to model the complex interactions between users and the tracking jammer.In the proposed game,users act as leaders,chose their channel access strategies and transmit firstly.The tracking jammer acts as the follower,whose objective is to find the optimal jamming strategy at each time slot.Besides,the existence of Stackelberg equilibriums(SEs)is proved,which means users reach Nash Equilibriums(NEs)for each jamming strategy while the jammer finds its best response jamming strategy for the current network access case.An active attraction based anti-jamming channel access(3ACA)algorithm is designed to reach SEs,where jammed users keep their channel access strategies unchanged to create access chances for other users.To enhance the fairness of the system,users will adjust their strategies and relearn after certain time slots to provide access chances for those users who sacrifice themselves to attract the tracking jammer.
基金supported by the National Natural Science Foundation of China(51577094)the Natural Science Foundation of Jiangsu Province of China(BK20180086)。
文摘As one of prussian blue analogues,Co_(3)[Co(CN)_(6)]_(2) has been explored as a promising anode material for potassium-ion batteries(PIBs) owing to its high potassium storage capacity.Unfortunately,Co_(3)[Co(CN)_(6)]_(2) possesses low electronic conductivity and its structure collapses easily during potassiation and depotassiation,resulting in poor rate performance and cyclic stability.To solve these problems,we develop a facile multi-step method to successfully combine uniformCo_(3)[Co(CN)_(6)]_(2) nanocubes with rGO by C-O-Co bonds.As expected,these chemcial bonds shorten the distance betweenCo_(3)[Co(CN)_(6)]_(2) and rGO to the angstrom meter level,which significantly improve the electronic conductivity ofCo_(3)[Co(CN)_(6)]_(2).Besides,the complete encapsulation ofCo_(3)[Co(CN)_(6)]_(2) nanocubes by rGO endows the structure ofCo_(3)[Co(CN)_(6)]_(2) with high stability,thus withstanding repeated insertion/extraction of potassium-ions without visible morphological and structural changes.Benefiting from the abovementioned structural advantages,the CO3 [Co(CN)6]2/rGO nanocomposite exhibits a high reversible capacity of 400.8 mAh g^(-1) at a current density of 0.1 A g^(-1),an exceptional rate capability of 115.5 mAh g^(-1) at 5 A g^(-1), and an ultralong cycle life of 231.9 mAh g^(-1) at 0.1 A g^(-1) after 1000 cycles.Additionally,the effects of different amounts of rGO and different sizes ofCo_(3)[Co(CN)_(6)]_(2) nanocubes on the potassium storage performance are also studied.This work offers an ideal route to significantly enhance the electrochemical properties of prussian blue analogues.
基金supported by the National Natural Science Foundation of China (22179063)。
文摘Potassium-ion batteries(PIBs) as a substitute for lithium-ion batteries have aroused widespread attention and have been rapidly developed. In the positive electrode materials, polyanionic compound has a high working voltage and large reversible capacity on account of its distinct framework and the strong inducing effect of the anionic group. Herein, a KVPO_(4)F/reduced graphene oxide(KVPF/r GO) hybrid was fabricated via a simple multi-step approach as the polyanionic cathode material for PIBs. Profiting from the small size of KVPF nanoparticles and their uniform distribution in the r GO framework, the assynthesized KVPF/r GO hybrid manifests a large discharge capacity of 103.2 mAh g^(-1) with an outstanding energy density of 436.5 Wh kg^(-1). Through r GO decoration, the hybrid also demonstrates remarkable rate and cycling properties. By employing ex-situ X-ray diffraction(XRD) and X-ray photoelectron spectroscopy(XPS) techniques, the potassium storage mechanism of KVPF was clearly revealed. The facile preparation procedure and superior properties endow it great application prospects in large-scale energy storage.
基金supported by the National Natural Science Foundation of China (22179063, 22075147)。
文摘Transition-metal sulfides are widely used as anodes for potassium-ion batteries(PIBs) due to their low cost and high theoretical capacity.The practical application of such materials,however,is still impeded by their inherent low conductivity and obvious volume change during cycling.Herein,a flexible etchassisted sulfidation strategy is reported.According to the strategy,the multicore-shell(MCS) nanocapsule structure is constructed,and then mesoporous FeS2 nanoparticles are encapsulated in the hollow carbon shell with adjustable interior space.The product,MCS-FeS2@C-20,not only features optimized inner space,but also delivers a large reversible capacity(519 mAh g^(-1) at a current density of 50 mA g^(-1)),good rate capability(107 mAh g^(-1) at a high current density of 5 A g^(-1)) and excellent cycling stability(capacity retention rate of 84.2% over 500 cycles at 0.5 A g^(-1)),making it the promising anode material for PIBs.Notably,potassium-ion full cells(MCS-FeS_(2)@C-20//K_(0.4)CoO_(2)) also show an improved potassium storage performance.
基金supported by National Natural Science Foundation of China (No. 62071488 and No. 62061013)
文摘In multi-agent confrontation scenarios, a jammer is constrained by the single limited performance and inefficiency of practical application. To cope with these issues, this paper aims to investigate the multi-agent jamming problem in a multi-user scenario, where the coordination between the jammers is considered. Firstly, a multi-agent Markov decision process (MDP) framework is used to model and analyze the multi-agent jamming problem. Secondly, a collaborative multi-agent jamming algorithm (CMJA) based on reinforcement learning is proposed. Finally, an actual intelligent jamming system is designed and built based on software-defined radio (SDR) platform for simulation and platform verification. The simulation and platform verification results show that the proposed CMJA algorithm outperforms the independent Q-learning method and provides a better jamming effect.
基金the National Natural Science Foundation of China,Grant Nos.31860051 and 31360044.
文摘interactions,many flowers are known to display their attractive qualities,such as scent emission,flower rewards and floral vertical direction,in a rhythmic fashion.However,less is known about how plants regulate the relationship between these flower traits to adapt to pollinator visiting behavior and increase reproduction success.Here we investigated the adaptive significance of the flower bending from erect to downward in Trifolium repens.We observed the flowering dynamic characteristics(changes of vertical direction of florets,flowering number,pollen grain numbers,pollen viability and stigma receptivity over time after blossom)and the factors affecting the rate of flower bending in T.repens.Then we altered the vertical direction of florets in inflorescence of different types(upright and downward),and compared the pollinator behaviors and female reproductive success.Our results showed that florets opened sequentially in inflorescence,and then bend downwards slowly after flowering.The bending speed of florets was mainly influenced by pollination,and bending angle increased with the prolongation of flowering time,while the pollen germination rate,stigma receptivity and nectar secretion has a rhythm of“lowhigh-low”during the whole period with the time going.The visiting frequency of all the four species of pollinators on upward flowers was significantly higher than that of downward flowers,and they especially prefer to visit flowers with a bending angle of 30°–60°,when the flowers was exactly of the highest flower rewards(nectar secretion and number of pollen grains),stigma receptivity and pollen germination rate.The seed set ratio and fruit set ratio of upward flowers were significantly higher than downward flowers,but significantly lower than unmanipulated flowers.Our results indicated that the T.repens could increase female and male fitness by accurate pollination.The most suitable flower angle saves pollinators’visiting energy and enables them to obtain the highest nectar rewards.This coordination between plants and pollinators maximizes the interests of them,which is a crucial factor in initiating specialized plant-pollinator relationships.
基金supported by the General Programs (No. 41472219)the Foundations for Innovative Research Groups (No. 41521001) from the National Natural Science Foundation of China。
文摘Many investigations suggest that dissimilatory arsenate-respiring prokaryotes (DARPs) play a key role in stimulating reductive mobilization of As from solid phase into groundwater,but it is not clear how environmental Mn(Ⅱ) affects the DARPs-mediated reductive mobilization of arsenic.To resolve this issue,we collected soil samples from a realgar tailingsaffected area.We found that there were diverse arsenate-respiratory reductase (arr) genes in the soils.The microbial communities had high arsenate-respiring activity,and were able to efficiently stimulate the reductive mobilization of As.Compared to the microcosms without Mn(Ⅱ),addition of 10 mmol/L Mn(Ⅱ) to the microcosms led to 23.99%-251.79% increases in the microbial mobilization of As,and led to 133.3%-239.2% increases in the abundances of arr genes.We further isolated a new cultivable DARP,Bacillus sp.F11,from the arseniccontaminated soils.It completely reduced 1 mmol/L As(V) in 5 days under the optimal reaction conditions.We further found that it was able to efficiently catalyze the reductive mobilization and release of As from the solid phase;the addition of 2 mmol/L Mn(Ⅱ) led to 98.49%-248.78% increases in the F11 cells-mediated reductive mobilization of As,and70.6%-104.4% increases in the arr gene abundances.These data suggest that environmental Mn(Ⅱ) markedly increased the DARPs-mediated reductive mobilization of As in arseniccontaminated soils.This work provided a new insight into the close association between the biogeochemical cycles of arsenic and manganese.
基金the support from the National Natural Science Foundation of China (22179063)the support from the Australian Research Council through the ARC Linkage Project (LP200200926)。
基金supported by the Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)(Grant No.SML2021SP203)。
文摘Marine macroalgae cultivation is an important part of the effort to address climate change through carbon sinks.Gracilaria,especially Gracilaria lemaneiformis and Gracilaria lichenoides are the major macroalgae cultivated in China.This study proposes a method to assess the net carbon sink of marine macroalgae(Gracilaria)cultivation.First,the net carbon sink of Gracilaria cultivation in China is calculated based on the yield of annual cultivated Gracilaria recorded in China Fishery Statistical Yearbook from 2011 to 2020.Next,we predict the net carbon sink trend of Gracilaria cultivation from 2021 to 2030 using the autoregressive integrated moving average model(ARIMA).Finally,the potential carbon sink increase and methane reduction related to Gracilaria cultivation in China is explored through a scenario analysis.We find that the net carbon sink of Gracilaria cultivation in China was about 32.1-92.4 kilotons per year from 2011 to 2020,and shows a great annual growth trend.Moreover,the predicted net carbon sink of Gracilaria cultivation would increase to 77.8-191.4 kilotons per year from 2021 to2030,thereby could contribute considerably in the achievement of China's carbon peak goal.Under a scenario of producing ruminant green feed with additional Gracilaria cultivation,each ton of macroalgae is predicted to reduce carbon emission(i.e.,methane)by 0.33-0.68 tons.Thus,marine macroalgae cultivation might form a synergistic chain of"carbon sink increase-water purification-economy-methane reduction".This study proposes a synergistic new model that operates through marine macroalgae cultivation,economic aquaculture,and green feed production.
基金The authors acknowledge the funding from the Shenzhen Science and Technology Program(No.RCBS20210609103647030)National Natural Science Foundation of China(Nos.22005134,12275119,and 52227802)+3 种基金Guangdong Grant(No.2021ZT09C064)Major Science and Technology Infrastructure Project of Material Genome Big-science Facilities Platform supported by the Municipal Development and Reform Commission of Shenzhen,Guangdong-Hong Kong-Macao Joint Laboratory for Photonic-Thermal-Electrical Energy Materials and Devices(No.2019B121205001)the Open Research Fund of Songshan Lake Materials Laboratory(No.2022SLABFK04)Guangdong Basic and Applied Basic Research Foundation(No.2021A1515012403).
文摘Solid polymer electrolytes(SPEs)by in situ polymerization are attractive due to their good interfacial contact with electrodes.Previously reported in situ polymerized SPEs,however,suffer from the low polymerization degree that causes poor mechanical strength,Li dendrite penetration,and performance decay in Li-metal batteries.Although highly polymerized SPEs are more stable than lowly polymerized ones,they are restricted by their sluggish long-chain mobility and poor ionic conductivity.In this work,a three-dimensional fibrous membrane with ion selectivity was prepared and used as a functional filler for the in situ formed SPE.The obtained SPE has high stability due to its high polymerization degree after the long-term heating process.The fibrous membrane plays a vital role in improving the SPE’s properties.The rich anion-adsorption sites on the fibrous membrane can alleviate the polarization effect and benefit a uniform current distribution at the interface.The fibrous nanostructure can efficiently interact with the polymeric matrix,providing rich hopping sites for fast Li+migration.Consequently,the obtained SPE enables a uniform Li deposition and long-term cycling performance in Li-metal batteries.This work reported an in situ formed SPE with both high polymerization degree and ionic conductivity,paving the way for designing high-performance SPEs with good comprehensive properties.
