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Difference in metapopulation structure and dynamics of two species of coexistent melitaeine butterflies
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作者 WANG Yifei CHEN Jiejun +2 位作者 WANG Rongjiang LEI Guangchun XU Rumei 《Chinese Science Bulletin》 SCIE EI CAS 2003年第12期1239-1246,共6页
According to investigation on two species of melitaeine butterflies in Yanjiaping Village, Chicheng County, Hebei Province, China, between 1998—2002, to-gether with the use of 1︰10000 contour map of the local area, ... According to investigation on two species of melitaeine butterflies in Yanjiaping Village, Chicheng County, Hebei Province, China, between 1998—2002, to-gether with the use of 1︰10000 contour map of the local area, some conclusions are shown by the SPSS and GIS analysis of data obained from GPS: (1) The two species of melitaeine butterflies have different metapopulation struc-tures. M. phoebe is a source-sink metapopulation, while E. aurinia is a classical metapopulation, supporting the analytic result from our former genetic research. (2) The two species of melitaeine butterflies exhibit different trends of popula-tion dynamics. M. phoebe source-sink metapopulation is very unsteady, and is always small, thus has a tendency to go ex-tinct gradually. But E. aurinia classical metapopulation is stable, and has maintained a larger population size. There-fore, it stands a better chance of long-term survival. (3) The two species of melitaeine butterflies are significantly related in both patch occupancy and local population size. (4) The effect of isolation is significant on the metapopulations of these two species of melitaeine butterflies, consistent with the classical theories, whereas the effect of patch area is not sig-nificant on the metapopulations of these two species of meli-taeine butterflies, which is inconsistent with the classical theories. Therefore, other factors, such as habitat quality, should be considered for their influences on metapopula-tions. 展开更多
关键词 METAPOPULATION structure DYNAMICS coexistent Meli-taea PHOEBE Euphydryas aurinia.
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A nucleon-pair and boson coexistent description of nuclei
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作者 戴连荣 潘峰 J.P.Draayer 《Chinese Physics C》 SCIE CAS CSCD 2017年第7期67-72,共6页
We study a mixture of s-bosons and like-nucleon pairs with the standard pairing interaction outside an inert core. Competition between the nucleon-pairs and s-bosons is investigated in this scenario. The robustness of... We study a mixture of s-bosons and like-nucleon pairs with the standard pairing interaction outside an inert core. Competition between the nucleon-pairs and s-bosons is investigated in this scenario. The robustness of the BCS-BEC coexistence and crossover phenomena are examined through an analysis of pf-shell nuclei with realistic single-particle energies, in which two configurations with Pauli blocking of nucleon-pair orbits due to the formation of the s-bosons is taken into account. When the nucleon-pair orbits are considered to be independent of the s-bosons, the BCS-BEC crossover becomes smooth, with the number of the s-bosons noticeably more than that of the nucleon-pairs near the half-shell point, a feature that is demonstrated in the pf-shell for several values of the standard pairing interaction strength. As a further test of the robustness of the BCS-BEC coexistence and crossover phenomena in nuclei, results are given for B(E2; 01^+→21^+) values of even-even ^102-130 Sn with ^100Sn taken as a core and valence neutron pairs confined within the 1d(5/2), 0g(7/2), 1d(3/2), 2s(1/2), 1h(11/2)orbits in the nucleon-pair orbit and the s-boson independent approximation. The results indicate that the B(E2) values are reproduced well. 展开更多
关键词 shell model interacting boson model the BCS-BEC coexistence
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Occupancy and coexistence patterns of sympatric felid species in human-disturbed tropical habitats of Xishuangbanna,southwestern China 被引量:1
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作者 Ying Liu Ru-Chuan He +2 位作者 Lin Wang Christos Mammides Rui-Chang Quan 《Zoological Research(Diversity and Conservation)》 2025年第1期55-64,共10页
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
关键词 Anthropogenic disturbance CARNIVORES Conservation Spatio-temporal interaction Species coexistence
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A Shared Journey
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作者 WANG HENG XU MENGYAO ZHONG YINING 《ChinAfrica》 2025年第5期16-17,共2页
China–Africa cooperation provides practical solutions to development challenges and strengthens global governance.Beginning with the landmark 1955 Bandung Conference,China and African nations embarked on a path of so... China–Africa cooperation provides practical solutions to development challenges and strengthens global governance.Beginning with the landmark 1955 Bandung Conference,China and African nations embarked on a path of solidarity and cooperation.Over the past seven decades,guided by the Five Principles of Peaceful Coexistence and the Bandung Spirit of“solidarity,friendship,and cooperation,”both sides have explored independent development paths and confronted global challenges together. 展开更多
关键词 Bandung Conference bandung spirit SOLIDARITY five principles peaceful coexistence global challenges Peaceful Coexistence development challenges China Africa Cooperation
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Planting Tomorrow Agricultural heritage from past to future
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《China Report ASEAN》 2025年第10期16-17,共2页
Agricultural heritage refers to distinctive farming systems shaped by long-term synergistic evolution of humans and their environment.Safeguarding this heritage is fundamentally about preserving the wisdom of harmonio... Agricultural heritage refers to distinctive farming systems shaped by long-term synergistic evolution of humans and their environment.Safeguarding this heritage is fundamentally about preserving the wisdom of harmonious coexistence between humanity and nature.It is indispensable for maintaining global biodiversity,ensuring food and livelihood security,and enhancing resilience against climate change. 展开更多
关键词 biodiversity agricultural heritage climate change enhancing resilience climate change preserving wisdom harmonious coexistence farming systems COEXISTENCE maintaining global biodiversityensuring
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Xi Jinping——a Champion of Mutual Learning among Civilisations
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作者 Huang Yinjiazi 《International Understanding》 2025年第2期1-5,共5页
Tolerance,coexistence,exchanges and mutual learning among different civilisations play an irreplaceable role in advancing humanity's modernisation process when the future of all countries are closely connected.
关键词 mutual learning EXCHANGES civilisations TOLERANCE modernisation process COEXISTENCE
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巴厘岛:和谐的度假天堂
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作者 赫贵祥 《疯狂英语(初中天地)》 2025年第8期22-25,共4页
从鲜花供品到静居日,从梯田游览到海浪驰骋,巴厘岛让我们放慢脚步,瞬间发现喜悦。Imagine a vacation that feels like stepping into a reallife adventure game.That's Bali!Its special secret is called"menyama braya,&qu... 从鲜花供品到静居日,从梯田游览到海浪驰骋,巴厘岛让我们放慢脚步,瞬间发现喜悦。Imagine a vacation that feels like stepping into a reallife adventure game.That's Bali!Its special secret is called"menyama braya,"which means living peacefully with everything and everyone. 展开更多
关键词 peaceful coexistence VACATION HARMONY living peacefully everything everyone BALI ADVENTURE menyama braya
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Call variation and calling site preference of three sympatric Boulenophrys frogs
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作者 Tianyu Qian Yuanlingbo Shang +2 位作者 Wenbao Zheng Pipeng Li Daode Yang 《Current Zoology》 2025年第4期492-503,共12页
Animals living in syntopy share acoustic space.Asian horned frogs are well known for their sympatric distribution,but little is known about their strategies to avoid acoustic niche competition.This study focused on th... Animals living in syntopy share acoustic space.Asian horned frogs are well known for their sympatric distribution,but little is known about their strategies to avoid acoustic niche competition.This study focused on three sympatric Boulenophrys frog species from southern China—B.nanlingensis,B.ombrophila,and B.shimentaina,with the former two species call in similar frequencies but breed in different seasons.First,we checked the call variation during the change of individual body size and the ambient air temperature in three species.We have found call frequencies were the most static parameters in each species that were associated with body size and contributed most to species identifcation.Temporal call parameters shift with temperature but are mostly infuenced by low temperatures.Second,we checked the interactions between the environment and call properties.The calling site preferences of each species corresponded well with the prediction of the acoustic adaptation hypothesis(in view of higher frequency better transmission in open habitat),and species with similar call frequencies have some aspects of common calling sites.Third,we checked the species–species interaction by using playback tests with male B.nanlingensis.Results from playback experiments showed species that call at similar frequencies could hardly share the same habitat during the same season.These fndings expanded the knowledge of acoustic coexistence in closely related anuran species and provided insights into the vocal behavior of Asian horned frogs. 展开更多
关键词 bioacoustic niche communication coexisting species evolution vocal behavior
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Pursuing Peaceful Coexistence of Humans and Nature
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作者 ZHAO XIANG 《China Today》 2025年第6期66-70,共5页
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
关键词 societal support environmental protectionit peaceful coexistence ECOSYSTEMS local guardians environmental protection PARTICIPATION
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Driving role of acid mine drainage on microbial community assembly and species coexistence in paddy soil profiles
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作者 Shengni Tian Yufei Dong +5 位作者 Shouyang Pang Guokai Yuan Sisi Cai Penghui Zhang Yupeng Chen Mingzhu Zhang 《Journal of Environmental Sciences》 2025年第10期771-783,共13页
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
关键词 Acid mine drainage Soil depths Microbial community Metabolic pathways Community assembly Species coexistence
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Analysis and image encryption of memristive chaotic system with coexistence bubble
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作者 Da Qiu Bo Zhang +2 位作者 Tingting Zhang Song Liu Peiyu He 《Chinese Physics B》 2025年第4期250-260,共11页
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
关键词 coexistence bubble extreme multistability clustered oscillation anti-monotonicity
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Concurrent occurrence of adenocarcinoma and urothelial carcinoma of the prostate:Coexistence mechanisms from multiple perspectives
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作者 Xu-Chang Liu Yu-Xiang Liu Chun Liu 《World Journal of Clinical Cases》 2025年第12期5-9,共5页
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
关键词 Prostate adenocarcinoma Prostate urothelial carcinoma Coexistence mechanism Transformation mechanism TUMOR
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The influence mechanism of liquid sedimentary layers in urban underground spaces on the characteristics of natural gas explosions and damage risk
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作者 Qi Jing Zi-Yu Fan +1 位作者 Rui Zhou Yun-Tao Li 《Petroleum Science》 2025年第6期2619-2629,共11页
Gas explosions are a frequent hazard in underground confined spaces in the process of urban development.Liquid sedimentary layers,commonly present in these environments,have not been sufficiently studied in terms of t... Gas explosions are a frequent hazard in underground confined spaces in the process of urban development.Liquid sedimentary layers,commonly present in these environments,have not been sufficiently studied in terms of their impact on explosion dynamics.This study aims to investigate how gas-liquid two-phase environments in confined underground spaces affect the explosion characteristics of natural gas.To achieve this,experiments are conducted to examine the propagation of natural gas explosions in water and diesel layers,focusing on the influence of liquid properties and the liquid fullness degree(Lx)on explosion behavior.The results indicate that the presence of a liquid layer after the initial ignition stage significantly attenuates both the peak overpressure and the rise speed of pressure,in comparison to the natural gas conditions.During the subsequent explosive reaction,the evaporation and combustion of the diesel surface resulted in a distinct double-peak pressure rise profile in the diesel layer,with the second peak notably exceeding the first peak.Under conditions with a liquid sedimentary layer,the flame propagation velocities range from 6.53 to 34.1 m/s,while the overpressure peaks vary between 0.157 and 0.255 MPa.The explosion duration in both the water and diesel layer environments is approximately twice as long as that of the natural gas explosion,although the underlying mechanisms differ.In the diesel layer,the prolonged explosion time is attributed to the evaporation and combustion of the diesel,while in the water layer,the flame propagation velocity is significantly reduced.Under the experimental conditions,the maximum explosion energy reached 7.15×10~6J,corresponding to a TNT equivalent of 1.7.The peak overpressure surpassed the threshold for human fatality as defined by overpressure standards,posing a potential risk of damage to large steel-frame structures.The explosion shockwave in diesel layer conditions(L_(d)=0%,5%,7.5%,12.5%)and water layer(L_(w)=12.5%)conditions is observed to be sufficient to damage earthquake-resistant reinforced concrete.This study investigates the impact of sediment layer thickness and composition on gas explosions,and evaluates the associated explosion energy to assess human injuries and structural damage in underground environments.The findings of this study provide a scientific reference for urban underground safety. 展开更多
关键词 Underground space Liquid fullness degree Gas-liquid coexistence Peak overpressure Explosive risk
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Life in the Future
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作者 李文平 张超(指导) 《中学生英语》 2025年第26期7-7,共1页
What will our life be like in the future?With the development of science and technology,our life will get better and much more colorful.I think there must be great changes taking place in the future.Maybe cars will mo... What will our life be like in the future?With the development of science and technology,our life will get better and much more colorful.I think there must be great changes taking place in the future.Maybe cars will move on the way without drivers.Some cities will be built under the sea and humans will live with sea animals.Robots will help us cook food and do some cleaning. 展开更多
关键词 science technologyour underwater cities human animal coexistence future life science technology robot assistance car automation
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Dezincification of electric furnace dust by steel slag synergistic calcification carbothermal reduction
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作者 Dong-jie Zhou Jia-yong Qiu +6 位作者 Wei-tong Du Chuan-bo Zheng Rui Mao Hai-wei Yao En-wei Wu Liu-yu Zhang Dian-chun Ju 《Journal of Iron and Steel Research International》 2025年第7期1961-1977,共17页
Resource utilization of metallurgical solid waste is vital for the sustainable development of the steel industry in the context of“dual carbon.”The calcification-carbothermal reduction method was employed to extract... Resource utilization of metallurgical solid waste is vital for the sustainable development of the steel industry in the context of“dual carbon.”The calcification-carbothermal reduction method was employed to extract zinc and iron from electric furnace dust effectively.In this process,calcium oxide reacts with zinc ferrite to form dicalcium ferrite and zinc oxide,which further promotes the effective separation of zinc and iron.However,the addition of pure calcium oxide increases production costs for steel companies.Herein,a new process for dust removal and zinc recovery in electric furnaces has been developed,using electric furnace slag as a calcium agent and mineral trough ash as a reducing agent.Large amounts of dicalcium ferrate phases were detected in the carbothermal reduction products by steel slag synergistic calcification.The reaction mechanism was determined as ZnFe_(2)O_(4)+CaO→Ca_(2)Fe_(2)O_(5)+ZnO→Ca_(2)Fe_(2)O_(5)+Zn(g).Such a two-step reaction path indicated that steel slag can effectively promote the reduction and volatilization of zinc.The experimental optimal roasting parameters were determined as roasting temperature of 1150℃,roasting time of 45 min,calcium to zinc molar ratio of 1.1,and carbon to oxygen molar ratio of 0.8.The mass percentage of added steel slag was recorded as 21.83%,while that of mineral trough ash was 21.85%.Under these conditions,the zinc removal rate above 99%and the metallization rate of pellets of about 75.31%were achieved.Overall,the proposed method looks promising for future efficient separation of zinc and iron in industrial steel slag. 展开更多
关键词 Steel slag Electric furnace dust Coexisting calcification Carbothermal reduction DEZINCIFICATION
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Indolent T-cell lymphoma of the gastrointestinal tract coexisting with gastric signet-ring cell carcinoma:A case report and review of literature
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作者 Xue Chen Jia-Qi Bo +7 位作者 Xiao-Xiang Gao Su-Xia Zhang Jie Li Hui Wang Mu-Ye Yang Qian-Qian Guo Bing Xiu Yu Zeng 《World Journal of Gastroenterology》 2025年第47期172-181,共10页
BACKGROUND Indolent T-cell lymphoma of the gastrointestinal tract(iTCL-GI)is a rare mature T-cell lymphoma that has been formally recognized as a distinct entity in the 5th Edition World Health Organization Classifica... BACKGROUND Indolent T-cell lymphoma of the gastrointestinal tract(iTCL-GI)is a rare mature T-cell lymphoma that has been formally recognized as a distinct entity in the 5th Edition World Health Organization Classification of Tumours of Haematolymphoid Tumours.However,the coexistence of iTCL-GI with epithelial malignancies is rare in clinical practice.This study reports a case of iTCL-GI with gastric signet-ring cell carcinoma(SRCC).We aim to increase diagnostic awareness among clinicians and pathologists regarding multiple primary tumors.CASE SUMMARY A 65-year-old female presented with a 5-month history of lower abdominal pain,bloating,and vomiting.An abdominal computed tomography scan revealed irregular thickening of the gastric wall.Endoscopy revealed diffuse mucosal edema and rigid mucosa along the lesser curvature of the gastric body.There was a 1.5 cm mucosal protrusion on the greater curvature.Biopsy revealed that the lamina propria was expanded by a dense,nondestructive infiltrate of small lymphocytes in the greater curvature,which were characterized by a CD3+/CD8+/TIA-1+immunophenotype with a low Ki-67 index.Clonal T-cell receptor rearrangement was detected,but the Epstein-Barr virus encoded RNA's was negative.Lesions on the lesser curvature of the gastric body were confirmed to be SRCCs.After three months of follow-up,the patient completed four cycles of chemotherapy targeting the SRCC.While her abdominal pain improved,she experienced a weight loss of 5 kg.CONCLUSION Clinicians and pathologists must integrate assessment of these rare cases to prevent misdiagnosis and guide clinical practice. 展开更多
关键词 Indolent T-cell lymphoma Gastrointestinal tract Signet-ring cell carcinoma COEXISTENCE DIAGNOSIS Case report
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Coexistence of a Cross-Diffusive West Nile Virus Model with Variable Coefficients
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作者 YAN Chun-yue ZHU Min XU Yong 《安徽师范大学学报(自然科学版)》 2025年第4期301-315,共15页
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
关键词 West Nile virus heterogeneous environment CROSS-DIFFUSION coexistence solution
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Relationship of Water Uptake Depth with Tree Height and Resource-Use Strategies in a Warm-Temperate Secondary Forest in Central Japan
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作者 Michiko Nakagawa Naoko Matsuo +1 位作者 Celegeer Katsuura Hiiragi 《Journal of Environmental & Earth Sciences》 2025年第3期229-239,共11页
Understanding water uptake depth and its relationship with functional traits offers valuable insights into resource-use partitioning among coexisting tree species as well as forest responses to drought.However,knowled... Understanding water uptake depth and its relationship with functional traits offers valuable insights into resource-use partitioning among coexisting tree species as well as forest responses to drought.However,knowledge about water uptake patterns in vertical soil layers,especially among increasingly widespread secondary forest tree species,remains limited.In this study,we investigated interspecific and seasonal variations in water uptake depth among seven coexisting tree species over a 2-year period in a warm-temperate secondary forest in central Japan.We also analyzed the relationships of water uptake depth with tree height and functional traits,including specific leaf area(SLA),leaf dry matter content(LDMC),leaf nitrogen(N)content,and wood density(WD),to discern resource-use and-acquisition strategies.Results revealed that taller trees,especially when soil water is scarce,tend to access deeper soil water sources,indicating that water source partitioning is correlated with tree height.This interspecific and temporal variation in water sources likely stratifies trees to facilitate coexistence within the forest.Water uptake depth was primarily associated with WD and LDMC:trees absorbing more water from shallow soils during dry conditions exhibited lower WD and LDMC,indicating a proactive resource-use strategy.Conversely,SLA and leaf N content were orthogonal to water uptake depth,suggesting that strategies for acquiring belowground and aboveground resources may differ.Considering the alternation of tree species composition during secondary forest succession,our study highlights the importance of further data collection regarding root water uptake depth along successional stages to understand dynamic shifts in water uptake sources. 展开更多
关键词 Functional Traits Resource Partitioning Stable Isotopes Tree Species Coexistence Rooting Depth
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On shape coexistence and possible shape isomers of nuclei around^(172)Hg
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作者 Xin Guan Jing Guo +2 位作者 Qi-Wen Sun Bożena Nerlo-Pomorska Krzysztof Pomorski 《Nuclear Science and Techniques》 2025年第7期191-203,共13页
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
关键词 Macro-micro-model Shape coexistence Shape isomers Exact and BCS pairing solutions
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A dynamic spectrum and power allocation method for co-located pulse radar and communication system coexistence
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作者 Youwei MENG Yaoyao LI +1 位作者 Shaoxiong CAI Donglin SU 《Chinese Journal of Aeronautics》 2025年第4期501-512,共12页
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
关键词 Communication systems Dynamic multi-objective optimization Electromagnetic compatibility Radar-communication coexistence Spectrum and power allocation
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