Three-quasiparticle K-isomeric states in odd-mass N=106 isotones within the A~180 mass region were systematically investigated using configuration-constrained potential energy surface calculations.The calculations suc...Three-quasiparticle K-isomeric states in odd-mass N=106 isotones within the A~180 mass region were systematically investigated using configuration-constrained potential energy surface calculations.The calculations succes sfully reproduced the excitation energies and deformations of the known high-K isomers in nuclei from 175Tm to 181Re.For the nuclei closer to the Z=82 shell closure(^(183)Ir,^(185)Au,and^(187)Tl),predictions of the configurations of the observed and yet-to-be-observed isomers are provided.The results reveal strong shape polarization,where the three-quasiparticle states are driven to larger deformations compared to the often shape-soft or spherical ground states.A particularly rich spectrum of shape coexistence is predicted in^(187)Tl,where several high-K three-quasiparticle configurations with distinct prolate,oblate,and triaxial shapes are found to coexist at similar excitation energies.Notably,the oblate-deformed K^(π)=29/2^(+)configuration at E_(x)=1839 keV was proposed to be responsible for a long-lived isomer.This study provides a comprehensive picture of shape evolution and coexistence in high-K multi-quasiparticle states,offering valuable insights for future experimental studies.展开更多
Halogens are common in industrial thermal processes and can induce formation of toxic organic pollutants.Currently,the specific effects of coexisting halogens on toxic pollutant formation are unclear.In this study,we ...Halogens are common in industrial thermal processes and can induce formation of toxic organic pollutants.Currently,the specific effects of coexisting halogens on toxic pollutant formation are unclear.In this study,we found the boosting effects of halogens on organic pollutants formation during thermal processes.In situ electron paramagnetic resonance spectroscopy was used to distinguish the organic free radical intermediates of organic pollutants during thermal processes.The pure chlorine-containing reaction system dominantly induce the formation of highly chlorinated phenoxy radicals,whereas the pure bromine-containing reaction system induce the formation of semiquinone radicals.The results provide clear evidence for the molecular mechanisms by which halogen coexistence boosts pollutants formation.Coexisting halogens made the reactions much more complex.Bromine atom radicals(Br·)can enhance the level of active chlorine atoms radicals(Cl·),then(1)facilitating highly chlorinated organic radicals and toxic pollutants formation,(2)activating polycyclic aromatic hydrocarbons molecules for subsequent ring growth and(3)accelerating oxidation reactions.Combining the identification of organic free radical intermediates and characteristics of products,detailed mechanisms of halogens on the formations of organic pollutants during thermal-related processes were clarified,which can be helpful for their efficient control in the widespread bromines and chlorines co-existence reaction system.展开更多
In recent years,the phenomenon of multistability has attracted wide attention.In this paper,a memristive chaotic system with extreme multistability is constructed by using a memristor.The dynamic behavior of the syste...In recent years,the phenomenon of multistability has attracted wide attention.In this paper,a memristive chaotic system with extreme multistability is constructed by using a memristor.The dynamic behavior of the system is analyzed by Poincar´e mapping,a time series diagram,and a bifurcation diagram.The results show that the new system has several significant characteristics.First,the new system has a constant Lyapunov exponent,transient chaos and one complete Feigenbaum tree.Second,the system has the phenomenon of bifurcation map shifts that depend on the initial conditions.In addition,we find periodic bursting oscillations,chaotic bursting oscillations,and the transition of chaotic bursting oscillations to periodic bursting oscillations.In particular,when the system parameters take different discrete values,the system generates a bubble phenomenon that varies with the initial conditions,and this bubble can be shifted with the initial values,which has rarely been seen in the previous literature.The implementation by field-programmable gate array(FPGA)and analog circuit simulation show close alignment with the MATLAB numerical simulation results,validating the system’s realizability.Additionally,the image encryption algorithm integrating DNA-based encoding and chaotic systems further demonstrates its practical applicability.展开更多
Felid species hold critical ecological roles within tropical forest ecosystems and are particularly susceptible to human-induced disturbances.However,there is limited research on how sympatric felid species are distri...Felid species hold critical ecological roles within tropical forest ecosystems and are particularly susceptible to human-induced disturbances.However,there is limited research on how sympatric felid species are distributed and coexist in human-dominated habitats.Using a long-term camera trap survey conducted in the disturbed tropical habitats of Xishuangbanna,southwestern China,we assessed the occupancy and spatio-temporal segregation among four sympatric felid species(Leopard cat Prionailurus bengalensis,Marbled cat Pardofelis marmorata,Asiatic golden cat Catopuma temminckii,and Clouded leopard Neofelis nebulosa),and explored how these patterns correlate with similarities in species traits.We found that the occupancy probabilities of leopard cats and clouded leopards were primarily influenced by anthropogenic disturbances rather than natural factors,with both species negatively affected by croplands.Similar species responses to croplands and livestock may facilitate the co-occurrence of leopard cats with clouded leopards in areas farther from croplands and with golden cats in regions with higher livestock abundance.The lack of significant spatial segregation among species is likely due to the observed segregation in daily activity patterns,which positively correlated with species trait similarities.Our study enhances our understanding of felid community assembly in the face of expanding human activity,offering valuable insights for future conservation in the Xishuangbanna region.展开更多
This article discusses the coexistence of prostate adenocarcinoma and prostate urothelial carcinoma.Combining existing literature and research results,the potential mechanisms of the co-occurrence of these two cancers...This article discusses the coexistence of prostate adenocarcinoma and prostate urothelial carcinoma.Combining existing literature and research results,the potential mechanisms of the co-occurrence of these two cancers are explored,including the role of androgen receptor,gene mutations,and their complex interactions in cell signaling pathways,etc.Also,the hypothesis of prostate cancer transformation into urothelial carcinoma is explained from some perspectives,including tumor multipotent stem cell differentiation,epithelial-mesenchymal transition,mesenchymal-epithelial transition,and other mechanisms.Ultimately,the goal is to provide more accurate diagnoses and more personalized treatments in clinical practice,as well as to lay the foundation for improving patient prognoses in the future.展开更多
In order to understand the transmission mechanism of West Nile virus(WNv)in birds(especially crows)and mosquitoes populations,this paper extends the traditional ordinary differential model of WNv to a reaction-diffusi...In order to understand the transmission mechanism of West Nile virus(WNv)in birds(especially crows)and mosquitoes populations,this paper extends the traditional ordinary differential model of WNv to a reaction-diffusion system with more complex cross-diffusion.We explore the relationship between the basic reproduction number and cross-diffusion coefficients involving various parameters,and investigate the effect of vertical transmission of the virus on the transmission mechanism.We use the method of upper and lower solutions to investigate the existence of the coexistence solutions.The theoretical analysis and numerical simulation show that the WNv carried by birds and mosquitoes will coexist when the low-risk threshold R0*≥1,which is a disadvantage to the prevention and control of this virus,and disappear when the high-risk threshold R*0≤1,which is an advantage to that.展开更多
This study explores the phenomenon of shape coexistence in nuclei around^(172)Hg,with a focus on the isotopes^(170)Pt,^(172)Hg,and^(174)Pb,as well as the^(170)Pt to^(180)Pt isotopic chain.Utilizing a macro-microscopic...This study explores the phenomenon of shape coexistence in nuclei around^(172)Hg,with a focus on the isotopes^(170)Pt,^(172)Hg,and^(174)Pb,as well as the^(170)Pt to^(180)Pt isotopic chain.Utilizing a macro-microscopic approach that incorporates the Lublin-Strasbourg Drop model combined with a Yukawa-Folded potential and pairing corrections,we analyze the potential energy surfaces(PESs)to understand the impact of pairing interaction.For^(170)Pt,the PES exhibited a prolate ground state,with additional triaxial and oblate-shaped isomers.In^(172)Hg,the ground-state deformation transitions from triaxial to oblate with increasing pairing interaction,demonstrating its nearlyγ-unstable nature.Three shape isomers(prolate,triaxial,and oblate)were observed,with increased pairing strength leading to the disappearance of the triaxial isomer.^(174)Pb exhibited a prolate ground state that became increasingly spherical with stronger pairing.While shape isomers were present at lower pairing strengths,robust shape coexistence was not observed.For realistic pairing interaction,the ground-state shapes transitioned from prolate in^(170)Pt to a coexistence ofγ-unstable and oblate shapes in^(172)Hg,ultimately approaching spherical symmetry in^(174)Pb.A comparison between Exact and Bardeen-Cooper-Schrieffer(BCS)pairing demonstrated that BCS pairing tends to smooth out shape coexistence and reduce the depth of the shape isomer,leading to less pronounced deformation features.The PESs for even-even^(170)-180 Pt isotopes revealed significant shape evolution.^(170)Pt showed a prolate ground state,whereas^(172)Pt exhibited both triaxial and prolate shape coexistence.In^(174)Pt,the ground state was triaxial,coexisted with a prolate minimum.For^(176)Pt,aγ-unstable ground state coexists with a prolate minimum.By 178 Pt and 180Pt,a dominant prolate minimum emerged.These results highlight the role of shape coexistence andγ-instability in the evolution of nuclear structure,especially in the mid-shell region.These findings highlight the importance of pairing interactions in nuclear deformation and shape coexistence,providing insights into the structural evolution of mid-shell nuclei.展开更多
The environmental impacts of acid mine drainage(AMD)from open-pit mining are profoundly detrimental,yet knowledge about its effects on paddy soil microbial communities,especially at greater depths,remains limited.In t...The environmental impacts of acid mine drainage(AMD)from open-pit mining are profoundly detrimental,yet knowledge about its effects on paddy soil microbial communities,especially at greater depths,remains limited.In this investigation,we compared soils affected by AMD versus unaffected soil depth profiles in terms of bacterial diversity and community assembly.The profiles in AMD-polluted soils exhibited tight geochemical gradients,characterized by increased acidity,SO_(4)^(2-),NO_(3)^(-),and heavy metal content compared to unpolluted soils.Notably,AMD significantly diminished soil bacterial biodiversity.A depthwise analysis showed distinct microbial stratification,with certain bacteria like Candidatus_Solibacter and Candidatus_Koribacter predominated in polluted soils,while others like Haliangium and Nitrospira were more prevalent in control soils.Interestingly,despite variable soil conditions,predictedmetabolic pathways,particularly those involving carbon,nitrogen,and sulfur,showed relative stability.AMD pollution induced the upregulation of methylcoenzyme M reductase and sulfate reductase genes.Bacterial communities were more responsive to pH and nutrient content rather than heavy metals,with pH and SO_(4)^(2-)being the primary drivers of microbial diversity and distribution.Additionally,pHwas identified as the most significant influence on the predicted methane,sulfur,and nitrogen metabolism.Furthermore,deterministic processes played a more significant role in community assembly of polluted soils,while heterogeneous selection gained importance with increasing depth in control soils.Additionally,microbial co-occurrences,particularly positive interactions,were more prevalent in the polluted soils with reduced network modularity and keystone taxa.These findings offer insights into sustaining microbial diversity in extreme environments.展开更多
Scholars and volunteers have been dedicated to working together with local residence for nearly two decades to protect nature.AS the awareness of both the government and the general public has grown regarding environm...Scholars and volunteers have been dedicated to working together with local residence for nearly two decades to protect nature.AS the awareness of both the government and the general public has grown regarding environmental protection,it has become a general consensus that ecosystems need to be protected by relying on local guardians with broad societal support and participation.展开更多
Airborne pulse radar and communication systems are essential for precise detection and collision avoidance,ensuring that aircraft operate safely and efficiently.A major challenge in spectrum sharing is the allocation ...Airborne pulse radar and communication systems are essential for precise detection and collision avoidance,ensuring that aircraft operate safely and efficiently.A major challenge in spectrum sharing is the allocation of resources in both the time and frequency domains,aiming to minimize inter-system interference as the available spectrum fluctuates over time.In this paper,regarding maximization of detection probability and spectrum utilization efficiency as two fundamental objectives,a novel Dynamic Spectrum and Power Allocation based on Genetic Algorithm(GA-DSPA)model is proposed,which dynamically allocates communication channel frequency and power under the constraints of pulse radar detection probability and signal-to-interferenceplus-noise ratio of communication.To solve this bi-objective model,a non-dominated sortingbased multi-objective genetic algorithm is developed.A novel environment perception strategy and offspring sorting technique based on radar echoes are integrated into the optimization framework.Simulation results indicate that by integrating environmental monitoring mechanisms and dynamic adaptation strategies,the proposed method effectively tracks the evolving Paretooptimal Fronts(Po Fs),thereby ensuring optimal performance for both co-located pulse radar and communication systems.Hardware test results confirm that within the GA-DSPA framework,the pulse radar achieves higher detection probabilities under identical conditions,while the communication system realizes increased average throughput.展开更多
With the rapid development of commercial communications,the research on Radar-Communication Coexistence(RCC)systems is becoming a hot spot.The resource allocation techniques play a crucial role in the RCC systems.A pe...With the rapid development of commercial communications,the research on Radar-Communication Coexistence(RCC)systems is becoming a hot spot.The resource allocation techniques play a crucial role in the RCC systems.A performance-driven Joint Radar-target and Communication-user Assignment,along with Power and Subchannel Allocation(JRCAPSA)strategy,is proposed for an RCC network.The optimization model aims to minimize the sum of weighted Bayesian Cramer-Rao Lower Bounds(BCRLBs)of target state estimates for radar purpose.This is subject to constraints such as the Communication Data Rate(CDR)for communication purpose,the total power budget in each RCC system,assignment relationships,and the number of available subchannels.Considering that such a problem falls into the realm of Mixed Integer Programming(MIP),a Three-stage Iteratively Augment-based Optimization Method(TIAOM)is developed.The Communication-User Assignment(CUA),Communication Subchannel Allocation(SCA),and Radar-Target Assignment(RTA)feasible solution domains are iteratively expanded based on their importance,leading to the efficient acquisition of a suboptimal solution.Simulation results show the outperformance of the proposed JRCAPSA strategy,compared to the other benchmarks and the OPTI toolbox.The results also imply that the Bayesian Cramer-Rao Lower Bound(BCRLB)is a more stringent optimization metric for the achieved Mean Square Error(MSE),compared to Mutual Information(MI)and Signal-to-Interference-Noise Ratio(SINR).展开更多
Over 70 years ago,China proposed the Five Principles of Peaceful Coexistence,which were first embraced by countries such as Myanmar and gradually gained traction across Asia.The Five Principles eventually became widel...Over 70 years ago,China proposed the Five Principles of Peaceful Coexistence,which were first embraced by countries such as Myanmar and gradually gained traction across Asia.The Five Principles eventually became widely recognized norms in international relations and foundational principles of international law,contributing significantly to the post-World War II international order.Decades on,the Five Principles have not faded into history.Rather,they have demonstrated renewed relevance in today’s complex global landscape.展开更多
Cooperative multi-UAV search requires jointly optimizing wide-area coverage,rapid target discovery,and endurance under sensing and motion constraints.Resolving this coupling enables scalable coordination with high dat...Cooperative multi-UAV search requires jointly optimizing wide-area coverage,rapid target discovery,and endurance under sensing and motion constraints.Resolving this coupling enables scalable coordination with high data efficiency and mission reliability.We formulate this problem as a discounted Markov decision process on an occupancy grid with a cellwise Bayesian belief update,yielding a Markov state that couples agent poses with a probabilistic target field.On this belief–MDP we introduce a segment-conditioned latent-intent framework,in which a discrete intent head selects a latent skill every K steps and an intra-segment GRU policy generates per-step control conditioned on the fixed intent;both components are trained end-to-end with proximal updates under a centralized critic.On the 50×50 grid,coverage and discovery convergence times are reduced by up to 48%and 40%relative to a flat actor-critic benchmark,and the aggregated convergence metric improves by about 12%compared with a stateof-the-art hierarchical method.Qualitative analyses further reveal stable spatial sectorization,low path overlap,and fuel-aware patrolling,indicating that segment-conditioned latent intents provide an effective and scalable mechanism for coordinated multi-UAV search.展开更多
To address real-time path planning requirements for multi-unmanned aerial vehicle(multi-UAV)collaboration in environments,this study proposes an improved multi-agent deep deterministic policy gradient algorithm with p...To address real-time path planning requirements for multi-unmanned aerial vehicle(multi-UAV)collaboration in environments,this study proposes an improved multi-agent deep deterministic policy gradient algorithm with prioritized experience replay(PER-MADDPG).By designing a multi-dimensional state representation incorporating relative positions,velocity vectors,and obstacle distance fields,we construct a composite reward function integrating safe obstacle avoidance,formation maintenance,and energy efficiency for environment perception and multiobjective collaborative optimization.The prioritized experience replay mechanism dynamically adjusts sampling weights based on temporal difference(TD)errors,enhancing learning efficiency for high-value samples.Simulation experiments demonstrate that our method generates real-time collaborative paths in 3D complex obstacle environments,reducing training time by 25.3%and 16.8%compared to traditional MADDPG and multi-agent twin delayed deep deterministic policy gradient(MATD3)algorithms respectively,while achieving smaller path length variances among UAVs.Results validate the effectiveness of prioritized experience replay in multi-agent collaborative decision-making.展开更多
To address the challenge of achieving decentralized,scalable,and adaptive control for large-scale multiple unmanned aerial vehicle(multi-UAV)swarms in dynamic urban environments with obstacles and wind perturbations,w...To address the challenge of achieving decentralized,scalable,and adaptive control for large-scale multiple unmanned aerial vehicle(multi-UAV)swarms in dynamic urban environments with obstacles and wind perturbations,we proposed a hybrid framework integrating adaptive reinforcement learning(RL),multi-modal perception fusion,and enhanced pigeon flock optimization(PFO)with curiosity-driven exploration to enable robust autonomous and formation control.The framework leverages meta-learning to optimize RL policies for real-time adaptation,fuses sensor data for precise state estimation,and enhances PFO with learned leader-follower dynamics and exploration rewards to maintain cohesive formations and explore uncertain areas.For swarms of 10–30 UAVs,it achieves 34%faster convergence,61%reduced stability root mean square error(RMSE),88%fewer collisions and 85.6%–92.3%success rates in target detection and encirclement,outperforming standard multi-agent RL,pure PFO,and single-modality RL.Three-dimensional trajectory visualizations confirm cohesive formations,collision-free maneuvers,and efficient exploration in urban search-and-rescue scenarios.Innovations include meta-RL for rapid adaptation,multi-modal fusion for robust perception,and curiosity-driven PFO for scalable,decentralized control,advancing real-world multi-UAV swarm autonomy and coordination.展开更多
In many Chinese and American works,the differences of backgrounds,such as culture,customs and so on occupy a large part,through which readers can see the collision as well as coexistence between the two cultures.The J...In many Chinese and American works,the differences of backgrounds,such as culture,customs and so on occupy a large part,through which readers can see the collision as well as coexistence between the two cultures.The Joy Luck Club has no exception.In this work,the communication under different cultural backgrounds between the generations generates a lot of collision,but they get coexistence in the end.In this paper,the author will analyze the continuous collision and the final coexistence of the four pairs of mothers and daughters,so that readers can learn more about the differences between Chinese and American cultures.展开更多
On the basis of the characteristics of ancient Chinese culture,the paper discusses the formation inevitability of the 'Coexistence between Heaven and Man' building concept,the connection and the differences wi...On the basis of the characteristics of ancient Chinese culture,the paper discusses the formation inevitability of the 'Coexistence between Heaven and Man' building concept,the connection and the differences with the ecological concept of modern Chinese Vernacular Architecture.The key point is that the contemporary design should absorb the ancient Chinese culture of the 'Coexistence between Heaven and Man' building concept and the essence of Chinese Vernacular Architecture ecological concept,forming the design features of local ecology based on the environmental protection and harmonious coexistence.展开更多
As one of the best-known literary works of the American novelist Ursula K.Le Guin,The Left Hand of Darkness is not only successful in its splendid plots and beautiful language but also in the important function of its...As one of the best-known literary works of the American novelist Ursula K.Le Guin,The Left Hand of Darkness is not only successful in its splendid plots and beautiful language but also in the important function of its readers in reading.In the thesis,one of its themes,coexistence of opposites,is analyzed in the reader response perspective in order to reveal Le Guin's reader-consciousness.The theme exists on a higher level in the novel and expresses Le Guin's attitude towards life and universe.Le Guin unified her own philosophy in the novel and tried to call for the reader's resonance.展开更多
The coexistence theory of slag structure and it's application to calculation of the oxidizing capabilities of slag melts is described. It is shown that the law of mass action can be widely applied to the calculati...The coexistence theory of slag structure and it's application to calculation of the oxidizing capabilities of slag melts is described. It is shown that the law of mass action can be widely applied to the calculation of oxidizing capabilities of slag melts in combination with the coexistence theory of slag structure.For slag melts containing basic oxides FeO and MnO, their oxidizing capabilities can be expressed by N Fe tO =N FeO +6N Fe 2O 3 , while for slag melts containing basic oxides CaO, MgO, etc., in addition to FeO and MnO, their oxidizing capabilities can be given as N Fe tO =N FeO +6N Fe 2O 3 +8N Fe 3O 4 .展开更多
A mesocosm experiment was conducted to investigate whether plant coexistence affects cadmium （Cd） uptake by plant in contaminated soil. Tobacco （Nicotiana tabacum L. var. K326） and Japanese clover （Kummerowia str...A mesocosm experiment was conducted to investigate whether plant coexistence affects cadmium （Cd） uptake by plant in contaminated soil. Tobacco （Nicotiana tabacum L. var. K326） and Japanese clover （Kummerowia striata （Thunb.） Schindl.） were used. Cadmium was applied as 3CdSO4.SH2O in solution at three levels （0, 1, and 3 mg/kg soil） to simulate an unpolluted soil and soils that were slightly and moderately polluted with Cd. Tobacco （crop）, Japanese clover （non-crop）, and their combination were grown under each Cd treatment. Compared to monoculture and under all Cd treatments, co-planting with Japanese clover did not affect tobacco biomass but significantly increased Cd concentration in all tobacco tissues and enhanced Cd accumulation in tobacco shoots and roots. Compared to monoculture, co-planting reduced soil pH and increased Cd bioavailability. For tobacco, co-planting with Japanese clover increased the Cd bioconcentration factor （BCF） in Cd contaminated soil. Japanese clover also accumulated substantial quantities of Cd in shoots and roots. Thus, total Cd uptake by the plants was much greater with co-planting than with monoculture. The results suggested that phytoextraction can be effectively increased through tobacco co-planting with Japanese clover in mildly Cd-contaminated soil.展开更多
基金supported by the National Natural Science Foundation of China(No.12275369)。
文摘Three-quasiparticle K-isomeric states in odd-mass N=106 isotones within the A~180 mass region were systematically investigated using configuration-constrained potential energy surface calculations.The calculations succes sfully reproduced the excitation energies and deformations of the known high-K isomers in nuclei from 175Tm to 181Re.For the nuclei closer to the Z=82 shell closure(^(183)Ir,^(185)Au,and^(187)Tl),predictions of the configurations of the observed and yet-to-be-observed isomers are provided.The results reveal strong shape polarization,where the three-quasiparticle states are driven to larger deformations compared to the often shape-soft or spherical ground states.A particularly rich spectrum of shape coexistence is predicted in^(187)Tl,where several high-K three-quasiparticle configurations with distinct prolate,oblate,and triaxial shapes are found to coexist at similar excitation energies.Notably,the oblate-deformed K^(π)=29/2^(+)configuration at E_(x)=1839 keV was proposed to be responsible for a long-lived isomer.This study provides a comprehensive picture of shape evolution and coexistence in high-K multi-quasiparticle states,offering valuable insights for future experimental studies.
基金supported by the National Key Research and Development Program of China(No.2023YFC3707004)the National Natural Science Foundation of China(Nos.22376204,22076201 and 92143201)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(Nos.XDB0750400,XDB0750100 and XDB0750000)the Second Tibetan Plateau Scientific Expedition and Research Program(STEP)(No.2019 QZKK0605).
文摘Halogens are common in industrial thermal processes and can induce formation of toxic organic pollutants.Currently,the specific effects of coexisting halogens on toxic pollutant formation are unclear.In this study,we found the boosting effects of halogens on organic pollutants formation during thermal processes.In situ electron paramagnetic resonance spectroscopy was used to distinguish the organic free radical intermediates of organic pollutants during thermal processes.The pure chlorine-containing reaction system dominantly induce the formation of highly chlorinated phenoxy radicals,whereas the pure bromine-containing reaction system induce the formation of semiquinone radicals.The results provide clear evidence for the molecular mechanisms by which halogen coexistence boosts pollutants formation.Coexisting halogens made the reactions much more complex.Bromine atom radicals(Br·)can enhance the level of active chlorine atoms radicals(Cl·),then(1)facilitating highly chlorinated organic radicals and toxic pollutants formation,(2)activating polycyclic aromatic hydrocarbons molecules for subsequent ring growth and(3)accelerating oxidation reactions.Combining the identification of organic free radical intermediates and characteristics of products,detailed mechanisms of halogens on the formations of organic pollutants during thermal-related processes were clarified,which can be helpful for their efficient control in the widespread bromines and chlorines co-existence reaction system.
基金Project supported by the Natural Science Foundation of Hubei Province(Grant No.2024AFD068).
文摘In recent years,the phenomenon of multistability has attracted wide attention.In this paper,a memristive chaotic system with extreme multistability is constructed by using a memristor.The dynamic behavior of the system is analyzed by Poincar´e mapping,a time series diagram,and a bifurcation diagram.The results show that the new system has several significant characteristics.First,the new system has a constant Lyapunov exponent,transient chaos and one complete Feigenbaum tree.Second,the system has the phenomenon of bifurcation map shifts that depend on the initial conditions.In addition,we find periodic bursting oscillations,chaotic bursting oscillations,and the transition of chaotic bursting oscillations to periodic bursting oscillations.In particular,when the system parameters take different discrete values,the system generates a bubble phenomenon that varies with the initial conditions,and this bubble can be shifted with the initial values,which has rarely been seen in the previous literature.The implementation by field-programmable gate array(FPGA)and analog circuit simulation show close alignment with the MATLAB numerical simulation results,validating the system’s realizability.Additionally,the image encryption algorithm integrating DNA-based encoding and chaotic systems further demonstrates its practical applicability.
基金the National Natural Science Foundation of China(32371745)the Transboundary Cooperation on Biodiversity Research and Conservation in Gaoligong Mountains(E1ZK251)+3 种基金the 14th Five-Year Plan of the Xishuangbanna Tropical Botanical Garden,Chinese Academy of Sciences(E3ZKFF7B,E3ZKFF9B)the Yunnan Revitalization Talent Support Program“Innovation Team”Project(202405AS350019)Yunnan International Joint Laboratory for the Conservation and Utilization of Tropical Timber Tree Species(202403AP140004)the Postdoctoral Fellowship of Xishuangbanna Tropical Botanical Garden,CAS。
文摘Felid species hold critical ecological roles within tropical forest ecosystems and are particularly susceptible to human-induced disturbances.However,there is limited research on how sympatric felid species are distributed and coexist in human-dominated habitats.Using a long-term camera trap survey conducted in the disturbed tropical habitats of Xishuangbanna,southwestern China,we assessed the occupancy and spatio-temporal segregation among four sympatric felid species(Leopard cat Prionailurus bengalensis,Marbled cat Pardofelis marmorata,Asiatic golden cat Catopuma temminckii,and Clouded leopard Neofelis nebulosa),and explored how these patterns correlate with similarities in species traits.We found that the occupancy probabilities of leopard cats and clouded leopards were primarily influenced by anthropogenic disturbances rather than natural factors,with both species negatively affected by croplands.Similar species responses to croplands and livestock may facilitate the co-occurrence of leopard cats with clouded leopards in areas farther from croplands and with golden cats in regions with higher livestock abundance.The lack of significant spatial segregation among species is likely due to the observed segregation in daily activity patterns,which positively correlated with species trait similarities.Our study enhances our understanding of felid community assembly in the face of expanding human activity,offering valuable insights for future conservation in the Xishuangbanna region.
文摘This article discusses the coexistence of prostate adenocarcinoma and prostate urothelial carcinoma.Combining existing literature and research results,the potential mechanisms of the co-occurrence of these two cancers are explored,including the role of androgen receptor,gene mutations,and their complex interactions in cell signaling pathways,etc.Also,the hypothesis of prostate cancer transformation into urothelial carcinoma is explained from some perspectives,including tumor multipotent stem cell differentiation,epithelial-mesenchymal transition,mesenchymal-epithelial transition,and other mechanisms.Ultimately,the goal is to provide more accurate diagnoses and more personalized treatments in clinical practice,as well as to lay the foundation for improving patient prognoses in the future.
基金Supported by the Anhui Province Graduate Education Quality Engineering Project(2022jyjxggyj168)Anhui Province Higher Education Provincial-Level Quality Engineering Major Project(2022jcbs020)Anhui Province Higher Education Provincial-Level Quality Engineering General Project(2022jyxm527).
文摘In order to understand the transmission mechanism of West Nile virus(WNv)in birds(especially crows)and mosquitoes populations,this paper extends the traditional ordinary differential model of WNv to a reaction-diffusion system with more complex cross-diffusion.We explore the relationship between the basic reproduction number and cross-diffusion coefficients involving various parameters,and investigate the effect of vertical transmission of the virus on the transmission mechanism.We use the method of upper and lower solutions to investigate the existence of the coexistence solutions.The theoretical analysis and numerical simulation show that the WNv carried by birds and mosquitoes will coexist when the low-risk threshold R0*≥1,which is a disadvantage to the prevention and control of this virus,and disappear when the high-risk threshold R*0≤1,which is an advantage to that.
基金supported by the National Natural Science Foundation of China(Nos.12275115 and 12175097)the National Science Centre of Poland(No.2023/49/B/ST2/01294).
文摘This study explores the phenomenon of shape coexistence in nuclei around^(172)Hg,with a focus on the isotopes^(170)Pt,^(172)Hg,and^(174)Pb,as well as the^(170)Pt to^(180)Pt isotopic chain.Utilizing a macro-microscopic approach that incorporates the Lublin-Strasbourg Drop model combined with a Yukawa-Folded potential and pairing corrections,we analyze the potential energy surfaces(PESs)to understand the impact of pairing interaction.For^(170)Pt,the PES exhibited a prolate ground state,with additional triaxial and oblate-shaped isomers.In^(172)Hg,the ground-state deformation transitions from triaxial to oblate with increasing pairing interaction,demonstrating its nearlyγ-unstable nature.Three shape isomers(prolate,triaxial,and oblate)were observed,with increased pairing strength leading to the disappearance of the triaxial isomer.^(174)Pb exhibited a prolate ground state that became increasingly spherical with stronger pairing.While shape isomers were present at lower pairing strengths,robust shape coexistence was not observed.For realistic pairing interaction,the ground-state shapes transitioned from prolate in^(170)Pt to a coexistence ofγ-unstable and oblate shapes in^(172)Hg,ultimately approaching spherical symmetry in^(174)Pb.A comparison between Exact and Bardeen-Cooper-Schrieffer(BCS)pairing demonstrated that BCS pairing tends to smooth out shape coexistence and reduce the depth of the shape isomer,leading to less pronounced deformation features.The PESs for even-even^(170)-180 Pt isotopes revealed significant shape evolution.^(170)Pt showed a prolate ground state,whereas^(172)Pt exhibited both triaxial and prolate shape coexistence.In^(174)Pt,the ground state was triaxial,coexisted with a prolate minimum.For^(176)Pt,aγ-unstable ground state coexists with a prolate minimum.By 178 Pt and 180Pt,a dominant prolate minimum emerged.These results highlight the role of shape coexistence andγ-instability in the evolution of nuclear structure,especially in the mid-shell region.These findings highlight the importance of pairing interactions in nuclear deformation and shape coexistence,providing insights into the structural evolution of mid-shell nuclei.
基金supported by the Educational Commission of Anhui Province of China(No.KJ2021A0168)the Research Fund of Anhui Agricultural University(No.rc422112).
文摘The environmental impacts of acid mine drainage(AMD)from open-pit mining are profoundly detrimental,yet knowledge about its effects on paddy soil microbial communities,especially at greater depths,remains limited.In this investigation,we compared soils affected by AMD versus unaffected soil depth profiles in terms of bacterial diversity and community assembly.The profiles in AMD-polluted soils exhibited tight geochemical gradients,characterized by increased acidity,SO_(4)^(2-),NO_(3)^(-),and heavy metal content compared to unpolluted soils.Notably,AMD significantly diminished soil bacterial biodiversity.A depthwise analysis showed distinct microbial stratification,with certain bacteria like Candidatus_Solibacter and Candidatus_Koribacter predominated in polluted soils,while others like Haliangium and Nitrospira were more prevalent in control soils.Interestingly,despite variable soil conditions,predictedmetabolic pathways,particularly those involving carbon,nitrogen,and sulfur,showed relative stability.AMD pollution induced the upregulation of methylcoenzyme M reductase and sulfate reductase genes.Bacterial communities were more responsive to pH and nutrient content rather than heavy metals,with pH and SO_(4)^(2-)being the primary drivers of microbial diversity and distribution.Additionally,pHwas identified as the most significant influence on the predicted methane,sulfur,and nitrogen metabolism.Furthermore,deterministic processes played a more significant role in community assembly of polluted soils,while heterogeneous selection gained importance with increasing depth in control soils.Additionally,microbial co-occurrences,particularly positive interactions,were more prevalent in the polluted soils with reduced network modularity and keystone taxa.These findings offer insights into sustaining microbial diversity in extreme environments.
文摘Scholars and volunteers have been dedicated to working together with local residence for nearly two decades to protect nature.AS the awareness of both the government and the general public has grown regarding environmental protection,it has become a general consensus that ecosystems need to be protected by relying on local guardians with broad societal support and participation.
基金co-supported by the National Natural Science Foundation of China(No.62293495)the National Key Research and Development Program of China(No.2023YFB3306900)the Academic Excellence Foundation of BUAA for ph.D Students,China。
文摘Airborne pulse radar and communication systems are essential for precise detection and collision avoidance,ensuring that aircraft operate safely and efficiently.A major challenge in spectrum sharing is the allocation of resources in both the time and frequency domains,aiming to minimize inter-system interference as the available spectrum fluctuates over time.In this paper,regarding maximization of detection probability and spectrum utilization efficiency as two fundamental objectives,a novel Dynamic Spectrum and Power Allocation based on Genetic Algorithm(GA-DSPA)model is proposed,which dynamically allocates communication channel frequency and power under the constraints of pulse radar detection probability and signal-to-interferenceplus-noise ratio of communication.To solve this bi-objective model,a non-dominated sortingbased multi-objective genetic algorithm is developed.A novel environment perception strategy and offspring sorting technique based on radar echoes are integrated into the optimization framework.Simulation results indicate that by integrating environmental monitoring mechanisms and dynamic adaptation strategies,the proposed method effectively tracks the evolving Paretooptimal Fronts(Po Fs),thereby ensuring optimal performance for both co-located pulse radar and communication systems.Hardware test results confirm that within the GA-DSPA framework,the pulse radar achieves higher detection probabilities under identical conditions,while the communication system realizes increased average throughput.
基金supported by the National Natural Science Foundation of China(Nos.62071482,62471485,62471348)Shaanxi Association of Science and Technology Youth Talent Support Program Project,China(No.20230137)+1 种基金Innovative Talents Cultivate Program for Technology Innovation Team of ShaanXi Province,China(No.2024RS-CXTD-08)Youth Talent Lifting Project of the China Association for Science and Technology(No.2021-JCJQ-QT-018)。
文摘With the rapid development of commercial communications,the research on Radar-Communication Coexistence(RCC)systems is becoming a hot spot.The resource allocation techniques play a crucial role in the RCC systems.A performance-driven Joint Radar-target and Communication-user Assignment,along with Power and Subchannel Allocation(JRCAPSA)strategy,is proposed for an RCC network.The optimization model aims to minimize the sum of weighted Bayesian Cramer-Rao Lower Bounds(BCRLBs)of target state estimates for radar purpose.This is subject to constraints such as the Communication Data Rate(CDR)for communication purpose,the total power budget in each RCC system,assignment relationships,and the number of available subchannels.Considering that such a problem falls into the realm of Mixed Integer Programming(MIP),a Three-stage Iteratively Augment-based Optimization Method(TIAOM)is developed.The Communication-User Assignment(CUA),Communication Subchannel Allocation(SCA),and Radar-Target Assignment(RTA)feasible solution domains are iteratively expanded based on their importance,leading to the efficient acquisition of a suboptimal solution.Simulation results show the outperformance of the proposed JRCAPSA strategy,compared to the other benchmarks and the OPTI toolbox.The results also imply that the Bayesian Cramer-Rao Lower Bound(BCRLB)is a more stringent optimization metric for the achieved Mean Square Error(MSE),compared to Mutual Information(MI)and Signal-to-Interference-Noise Ratio(SINR).
基金phased achievement of the Yunnan Provincial Philosophy and Social Sciences Innovation Team project titled Research on Ethnic Issues and Their Impact in Northern Myanmar(No.2025CX09).
文摘Over 70 years ago,China proposed the Five Principles of Peaceful Coexistence,which were first embraced by countries such as Myanmar and gradually gained traction across Asia.The Five Principles eventually became widely recognized norms in international relations and foundational principles of international law,contributing significantly to the post-World War II international order.Decades on,the Five Principles have not faded into history.Rather,they have demonstrated renewed relevance in today’s complex global landscape.
文摘Cooperative multi-UAV search requires jointly optimizing wide-area coverage,rapid target discovery,and endurance under sensing and motion constraints.Resolving this coupling enables scalable coordination with high data efficiency and mission reliability.We formulate this problem as a discounted Markov decision process on an occupancy grid with a cellwise Bayesian belief update,yielding a Markov state that couples agent poses with a probabilistic target field.On this belief–MDP we introduce a segment-conditioned latent-intent framework,in which a discrete intent head selects a latent skill every K steps and an intra-segment GRU policy generates per-step control conditioned on the fixed intent;both components are trained end-to-end with proximal updates under a centralized critic.On the 50×50 grid,coverage and discovery convergence times are reduced by up to 48%and 40%relative to a flat actor-critic benchmark,and the aggregated convergence metric improves by about 12%compared with a stateof-the-art hierarchical method.Qualitative analyses further reveal stable spatial sectorization,low path overlap,and fuel-aware patrolling,indicating that segment-conditioned latent intents provide an effective and scalable mechanism for coordinated multi-UAV search.
基金supported by the open project of National Key Laboratory of Air-Based Information Perception and Fusion(No.202462)。
文摘To address real-time path planning requirements for multi-unmanned aerial vehicle(multi-UAV)collaboration in environments,this study proposes an improved multi-agent deep deterministic policy gradient algorithm with prioritized experience replay(PER-MADDPG).By designing a multi-dimensional state representation incorporating relative positions,velocity vectors,and obstacle distance fields,we construct a composite reward function integrating safe obstacle avoidance,formation maintenance,and energy efficiency for environment perception and multiobjective collaborative optimization.The prioritized experience replay mechanism dynamically adjusts sampling weights based on temporal difference(TD)errors,enhancing learning efficiency for high-value samples.Simulation experiments demonstrate that our method generates real-time collaborative paths in 3D complex obstacle environments,reducing training time by 25.3%and 16.8%compared to traditional MADDPG and multi-agent twin delayed deep deterministic policy gradient(MATD3)algorithms respectively,while achieving smaller path length variances among UAVs.Results validate the effectiveness of prioritized experience replay in multi-agent collaborative decision-making.
基金supported by the National Natural Science Foundation of China(No.62350048)。
文摘To address the challenge of achieving decentralized,scalable,and adaptive control for large-scale multiple unmanned aerial vehicle(multi-UAV)swarms in dynamic urban environments with obstacles and wind perturbations,we proposed a hybrid framework integrating adaptive reinforcement learning(RL),multi-modal perception fusion,and enhanced pigeon flock optimization(PFO)with curiosity-driven exploration to enable robust autonomous and formation control.The framework leverages meta-learning to optimize RL policies for real-time adaptation,fuses sensor data for precise state estimation,and enhances PFO with learned leader-follower dynamics and exploration rewards to maintain cohesive formations and explore uncertain areas.For swarms of 10–30 UAVs,it achieves 34%faster convergence,61%reduced stability root mean square error(RMSE),88%fewer collisions and 85.6%–92.3%success rates in target detection and encirclement,outperforming standard multi-agent RL,pure PFO,and single-modality RL.Three-dimensional trajectory visualizations confirm cohesive formations,collision-free maneuvers,and efficient exploration in urban search-and-rescue scenarios.Innovations include meta-RL for rapid adaptation,multi-modal fusion for robust perception,and curiosity-driven PFO for scalable,decentralized control,advancing real-world multi-UAV swarm autonomy and coordination.
文摘In many Chinese and American works,the differences of backgrounds,such as culture,customs and so on occupy a large part,through which readers can see the collision as well as coexistence between the two cultures.The Joy Luck Club has no exception.In this work,the communication under different cultural backgrounds between the generations generates a lot of collision,but they get coexistence in the end.In this paper,the author will analyze the continuous collision and the final coexistence of the four pairs of mothers and daughters,so that readers can learn more about the differences between Chinese and American cultures.
文摘On the basis of the characteristics of ancient Chinese culture,the paper discusses the formation inevitability of the 'Coexistence between Heaven and Man' building concept,the connection and the differences with the ecological concept of modern Chinese Vernacular Architecture.The key point is that the contemporary design should absorb the ancient Chinese culture of the 'Coexistence between Heaven and Man' building concept and the essence of Chinese Vernacular Architecture ecological concept,forming the design features of local ecology based on the environmental protection and harmonious coexistence.
文摘As one of the best-known literary works of the American novelist Ursula K.Le Guin,The Left Hand of Darkness is not only successful in its splendid plots and beautiful language but also in the important function of its readers in reading.In the thesis,one of its themes,coexistence of opposites,is analyzed in the reader response perspective in order to reveal Le Guin's reader-consciousness.The theme exists on a higher level in the novel and expresses Le Guin's attitude towards life and universe.Le Guin unified her own philosophy in the novel and tried to call for the reader's resonance.
文摘The coexistence theory of slag structure and it's application to calculation of the oxidizing capabilities of slag melts is described. It is shown that the law of mass action can be widely applied to the calculation of oxidizing capabilities of slag melts in combination with the coexistence theory of slag structure.For slag melts containing basic oxides FeO and MnO, their oxidizing capabilities can be expressed by N Fe tO =N FeO +6N Fe 2O 3 , while for slag melts containing basic oxides CaO, MgO, etc., in addition to FeO and MnO, their oxidizing capabilities can be given as N Fe tO =N FeO +6N Fe 2O 3 +8N Fe 3O 4 .
基金supported by the Science and Technology Department of Zhejiang Province (No. 2007C13063)the National Natural Science Foundation of China (No30970477)+1 种基金the Natural Science Foundation of Zhejiang Province (No. Y307418)the Key Laboratory of Ministry of Agriculture,China (No. KYJD09021)
文摘A mesocosm experiment was conducted to investigate whether plant coexistence affects cadmium （Cd） uptake by plant in contaminated soil. Tobacco （Nicotiana tabacum L. var. K326） and Japanese clover （Kummerowia striata （Thunb.） Schindl.） were used. Cadmium was applied as 3CdSO4.SH2O in solution at three levels （0, 1, and 3 mg/kg soil） to simulate an unpolluted soil and soils that were slightly and moderately polluted with Cd. Tobacco （crop）, Japanese clover （non-crop）, and their combination were grown under each Cd treatment. Compared to monoculture and under all Cd treatments, co-planting with Japanese clover did not affect tobacco biomass but significantly increased Cd concentration in all tobacco tissues and enhanced Cd accumulation in tobacco shoots and roots. Compared to monoculture, co-planting reduced soil pH and increased Cd bioavailability. For tobacco, co-planting with Japanese clover increased the Cd bioconcentration factor （BCF） in Cd contaminated soil. Japanese clover also accumulated substantial quantities of Cd in shoots and roots. Thus, total Cd uptake by the plants was much greater with co-planting than with monoculture. The results suggested that phytoextraction can be effectively increased through tobacco co-planting with Japanese clover in mildly Cd-contaminated soil.
